Power

Digitized by the Internet Archive

in 2010 with funding from

University of Toronto

http://www.archive.org/details/powereng34newy

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W)(vm^^

DEVOTED TO THE GENERATION AND
TRANSMISSION OF POWER

ISSUED WEEKLY

VOLUME XXXIV

July I to December 31, 1911

Hill Publishing Co.

505 PEARL STREET
NEW YORK

r^^

INDEX FOR VOLUME XXXIV

JULY I TO DECEMBER 31, 1911

Explanatory Note.

Illustrated articles are marked with an as-
terisk (•). Book notices are denoted by a
dagger (t). Cross references to a particular
initial word may apply to any cognate word
beginning in the same way. Tlius, a refer-
ence from "Oil" to "Lubricant" would relate
equally to "Lubricating," "Lubrication" or
"Lubricator." The cross references condense
the matter and assist the reader, but are not
t) be regai'ded as conclusive. So. if there
were a reference from "Boiler" to "Furnace"
and If the searcher failed to find the required
aiticle under the latter word, he should look
through the 'Boiler" entries, or others that
the topic might suggest, as he would have
done bad there been no cross reference. Let-
ters are indexed under title or subject, gen-
eral articles under writer's name as well
Not all articles relating to a given topic nec-
essarily appear under the same entries.

PAGE

Absorption kink. Maclntlre 153

Accidents. Gas-engine. Knowlton •954

Accidents, Power-plant, Prevention 30

Accounts, Operating maintenance ex-
pense 61i
Adams. R. W., transmission-line cal-
culator '155
Adams. \V. H., Engineers' wages,

China 855

"Addlstometcr" stroke recording in-
strument •154
Ai'roplane engines 378
Aftercooler. Air. Richards ^146
Air and steam bound pump. 8taley 042
Air chamber. l-:mergency. Loose *'!S1
Air, Compres<^od, Draining: aftercooler

and receiver. Richards •146

Air, Compressed, Power from. Macln-
tlre 698
All, Compressed. Using, In steam

hoists. Richards 475

Air comprosor and gas engine, Sar-
gent combined •550
Air compressor capacity, etc. 222
Air compressor. Kiiplex power-driven,

Ingorsoll Rand '305

Air ci.mprossor intake. Inertia of.

Rodflold •24',;. Loose •SOS

Air compressor knocking. McGahey •902

Air compressor motor — Sparking com-
mutator. Hawkins 666, 777, 893
Alr-compresHor piston. Wire In. Mur-

dock 743

Air compressor running under. D. C.
R. 189. Kimlmll, Blllson 205,
Tucker 41 'J. I'otorson 642. I.oo8e
•673. Richards 'TSO. Campbell,
Allen ftO!>, ,Iohn8on 034. Dreyer •90')
Air compressor. Steam-driven, econo-
mies. Sickles •807
Air romprossor — Unloader gave tron-

bio. Morton •931

Alrromprossor valvcii. Pneumatic lift

on. Soholowskl •«67

Air cooling and moisture precipitation 379
Air cylinder for <;onldB pnmp •lOS

Alr-dl»cbnrgo valves, Water-coolcil.

Rortrand •254

Air oxpWmlon". IMsastrous 47

Air (low through orlHce 752

Air gaps. Unbalanced. Wear of bear-
ings due to. Clapper 022
Air In Ice wator system. Hertor 304
Air lonkflg*^ — iMirnaco questions. Mc-

f;ahoT 67. Brown 183, Dumar 63

Airlift rnlcMlBllons 789

Air moisture, Effect of. Morlev et at

100, 118, 372. •436
Air piping to cool generator ^252

Air pressure. F.ffect of. Moore ^842

Air pump and auxiliary valve ^314

Air-pump efficiency. Improving — Spray

nozzle in suction pipe. Kamps 'S^T

Air pump, Leblanc. Ehrhart '48

Air pump, Rotary. Weir's *9C>i

.-Vir pump, \A'hy will it work with vac-
uum in suction pipe? Watts 'OOS
Air pumps. Rotary. European ' 'O^O
Air-receiver explosion. Newcomb 663
Air required to burn coal 222
Air-steam engines 'SSZ, 528, 603, 609,
•721, 934
Air trap. Hot-water heating •493
Air velocities. Measurement. Hechler

•341, Andeison 861

Air, Water vapor in 893

.\kron metallic gasket. Duplex 812

Alarm. Step bearing pump ^133

Alarm svstem. Fuel-oil beating and.

Hartley •OS

.\llcut. V.Trving steam to gas pro-
ducer •99, 109, 142
.Mien. Heat-transmission coefficients 32
Allgemeine Elek. Ges. turbine and

condenser investigations •550

.\Ilison. Temperature-conversion chart •ISl
— Santa Fi precooling plant •755

— Power development, Los Angeles

aqueduct ^478

— Pioneer power plant, Calif. •"SI

Alternating current power. C. M. 338

Alternating. Changing, to direct cur-
rent. Tupptr ^852
Alternating-current dynamos, Care

and operation. Meade •14, •174

Alternator. See also "Parallel,"

"Electricity"
Alternator.s, Small, Voltage troubles in.

Sprague 82

Alternators, Trouble with. Pox 66G,

Jackson, Smith 854

Alton boiler explosion. Chaddlck 185

American Boiler Mfrs." Asso. 150. 100.

223, 22S
American Elec. Ry. Eng. and Account-
ants' meeting 584, 590, 591, 611
American Gas & Elec. Co. ^549
American Inst. Boiler Inspectors 30, 722
American Inst. E. E. convention, Chi-
cago 59
American Order St. Eng. — Correction 40
American Soc. n. & V. Engineers •IIS, 192
•263, ^342
American Soc. Mech. Eng. See "En-
gineers"
American Soc. Refrig. Eng. 958, 959, 060
American Specialty Co.'s oil cup •269
American Steel & Wire Co.'s gas

clo.nnsing 895

American Woolen Co. plant ^876

Ammeter. Magnetomcchanlcal •286

Ammonln. See also "Refrigeration"
Ammonln Bb'<orption refrigerating sys-
tem. OphiilR 302
Ammonia compressor clearance. Bonn 153
Ammonln compressor. Protecting.

Schlndlor 'SOS. Delbort *6e0

Amm'inla compressor suction-pipe COT-

oring 712

Ammonia coniprossors. Operating, by

aid of thormomotors. Krledmann 059
Ammonia discharge pipe temperature.

T. L. D. 452. Aden R9S

Ammonia expansion valves 712

Ammonia Joint, Opening. Kcll 381,

Fagnan •eSO

Ammonia. Nonproclpltatlon of calclnm

chloride from brine by. Smith 058

Amslor. Now dynamomotor types •aoi

Anaconda mines air hoists 475

Annlvses. 1'ower-plant supply 568

Archos. Firebrick furnace, etc. .Tahnke
•441. Culira 600. Benenel 602,
Knight. Znnndke ^748. Ray ^782

Armnturo. 220 volt. Changing, to 110

volts. Cooper •803

Ashost'rfi. Making It stick 330

Ash bunker. Explosion In 800

PAOB

Ash, Coal, fusing temp. Bailey ^802, 864

Ashpits, Water in 929

Asleep on the Job. McGahey 147

Atlantic fleet. Power of 772

Atlas boiler circulating system ^430

Atlas Diesel engine test •778

Atwood combination wrench •812
Austin dam disaster 603, 678
Auxiliary machinery. Prime movers

for. London 610

Ayer mill plant. Rogers ^876

— Explosion in ash bunker 900

B

Babbitt In crank-pin box. Johnson •70S
Babbitt metal, Granulated, Making 229
—Oil-fuel test 170, 188
— Valve gear 914
Babcock & Wilcox headers, tubes, baf-
fle walls. Palrman 105, McVay 485
— Circulating system explained. Ma-

guire ^429
Back firing, Correcting. In large pro-
ducer-gas engine plant. Callan 57
Back-pressure valve. Troublesome,

Little ^707

Rack-pressure valves 962

Baffle plates. Milling. Read •596

Bagged water tubes. Werner 294
Bailey. Coal-ash fusing temp. •802, 864

Baker. B. Boston anti-smoke law 50
Baker, C. F., generator-ventilating

vanes •136

Baker refuse destructor •lOS

Balancing. Field needed. Davis 637

Ball. Steel vs. Iron pipe 060

Baltimore, Flywheel explosion •682

Banks gate valve ^539

Bartlett Graver softener and purifier 'M

Batcman. British Can. Power Co. •SSe

Bates Corliss engine Improvements ^498

Bates Mach. Co.'s Cookson heater ^37

Battery. Storage. Large plant, Balto. 326

Batteries. Storage. Frothing. Leesc 366

Bearing — Hot crosshead pin 640
Bearing, Main, experiences — Air pipe;
grooves ; wooden blocks, etc.

Powell •OS
Bearing. Poorly designed. McGahey

•559. Bennett ^829
Bearing pressures In gas engines.

Lewis. Kesslcr ^447

Bearing repair. Emergency 670

Be.irlng. Stop. Auto, pump for. Lynn •133

Bearing, Stop. room. Vernon, Vt. •UJO

Bearings, Distance between. II. R. C. 200

Bearings. Hot, Cause of. Blessing 441
Bearings. Hot, Cylinder oil for. JIc-

Leod 409
Bearings, Hot. Sand for 340. Howarlh
600. Cordnor 044. Freer 710,
Benoflol 74S, Sprnguo. I'orcnrd,
Bncklen 860. Wallace 935, Blake,

Ilurd. Kygor 988
Bearings. Hot. Sulphur, etc., for. Mc-
fiahov. Hollv, Mitchell 27, Board
106. Sterling 220, Blanrhard 332,

Baum .525, Hurst •598. Gould 673

"Bearings." Nelson's book on +230

Bearings, Oil grooves In. McGahey •OOO

Bearings, Pin, Bronze and babbitt 301
Bearings. Rv. motor, ILalntalnlng.

Fnottoror 252
Bearings. Sheet load prevented, from

heating. Bontley 105
Bearings, Wear of. due to unbalanced

alrgaps. Clapper 022
Bonttle. Cias engine Ignition equip-
ment 210
Ilodplnlos. Grouting. Holly 047
Bell crank repair •656
Bell single phase motor ^775
Bolt and pulley Inquiries 566
Bolt dressing. Graspit 811
Belt drive. Inloreotlng. Ashenden ^826
Bolt drives. Motor. WllllstOD 520,

Jackson 702

to December 31, 1911

Cox

862.
by

Belt, Excltcr^Malntalnlng tension

Belt-hook tool. Delvalle's

Belt length. R. F. H.

Belt ran to oide of pulloy. Mitchell

Belt speeds. Motor. Nichols

Belts, High-speed. Pulleys tor. Knorr

Belts. Shortening, In damp weather.

Belts, Size and care of. Wlllard 'll,

Mosher 220, King 221, Jackson
Belting and pulleys
Belting, Horsepower of
Btltlng length — Approximate rule
Belting. Power-plant
Belting — Pulley capacities. Sawdon

Belting vs. elec. transmission. .Tackson
Bement. Most economical amount of

Benjamin. Colors of piping
Bergmann turbine exhaust outlet
Berry. Apparatus for passing gas

samples to calorimeter
Betterment. Power-plant. Hunt,

2.''i. Bailey 374, Chapman
Bettlngton boiler
Bibbins' cooling tower design
Elbbv's boiler explosion, Eng.
Elery. Maintaining voltage

"forced draft"
Binns. lUcbmond's municipal plant '
Blaisdell. Gas-turolne problem '3G7,
Blakp, A. n. Cincinnati water works
— Drying out flooded substation '

— Power from sun's rays
— Curtis Pub. Co. plant
^Heating plant. N. V. Library
Blake-Knowles slush pump
Blast-furnace gas, Clean
Blast furnace gas engine, Youngstown,

Test
Blast-furnace plants, etc.. Gas engines

In '17. 142,

Bleeder turbine, Westlnghouse auto-
matic
Bleeding receiver to heat feed water

20.-!, Peek. Webster 444, F. R. L.
"Block" central station
Blower foundation. Concrete. McGa-

hey
Blower, Gas. set. High-pressure,

Sturtevant
BlowolT-pipe elbow explosion
Blowoff pipe. Plugged. Lyman
BlowofF valve burst. Drewry
Blowoff valve. Twinlok
Boat. Producer-gas canal tug
Bogert auxiliary heater

See also "Furnace." "Firing."
"Coal." ".Ash." "Oil," "Draft."
■ "Grate," "Valve (safety)."
"Steam," "Water," "Smoke."
"Gas," "Carbon dioxide." "Blow-
off." "Heating." "Corrosion,"
"Manhead." etc.

-Airleakage questions. McGahey 67,
Brown 183. Dumar

-Am. Boiler Mfrs.' Asso. 150, 160,
({fuestions discussed : Mass. and
other rules) 228,

-B. & W. headers, tubes, baffle walls.
Pairman ICJ. McVay

-Bagged water tubes. Werner

-Blister on boiler sheet

-Boiler Room Impvt. smoSe Indi-
cator

-Bricking furnace ; building arch.
Frew

—British smoke consumers ; water cir-
culator ; thermal column

-Bureau of Mines investigations 93,

-Carelessness In plant. Chapman

-Chicago river. Firing machine boil-
ers on

-Clean or pretty clean

-Cleaner — Dallett scaler

-Cleaner— "Diamond" soot blowers

•347.

-Cleaner, Vulcan soot — Manning
boiler

-Cleaners, Outside knocking

—Cleaning, tubes. Vert. boiler.
Bailey

-Cold boiler. Steam In. Roundy
2.')6. Fitts

—Compound feeder •293, Tank

—Cornell fuel economizer 30. 257.

—Corrosion. Taylor

—Corrosion. Holler, Preventing. In
gas-producer plants. GeofFrey

—Corrosion, steam hollers, Dunham

—Design -Butt straps, coned plates.
Manning boiler, etc. Terman.
Dean. .Tnckson

—Developments in European boilers
and furnaces — Borslg welding
practice: auxiliary grate; Bet
tlngton boiler for low-grade fuel,
etc. Christie

—Dilapidated boiler conditions.

McQueen

'810
832
410

748
393
838
940

291
178
193

PAGE

BOILER BOILER

— Draft, Poor : smoke connections.

Cotton •22, Hurd 185, Scott,

Howard 218, McGahey 220

— Dry-back marine boiler. Fenwlck

072, Webster, Harkness 869

— Efficiency tests — A. S. M. E. rules :

"combustible" 567, 71o

— EfBciencv. Boiler and furnace 60D

— Efficiency 83.ti9 p.e. — Parker holler

of Southern Paciflc, oil-fired •544, 568
—Evaporation and condensation 679

— Explodes under sidewalk. Boiler In

N. Y. '6*3. Ed lit

— Explosion averted. Hilton. Swope 107
— Explosion, Crucible Steel Co.'s 270

— Explosion, defects — Notes 177, 188

— Explosion, 111. Glass Co.'s, Alton.

Chaddick 185

— Explosion In England — Blbby's, at

Liverpool 862, 940

— Explosion. Low-wafer, Paragon

Paper Co. 349

— Explosion, Marine boiler. Steamer

"Diamond," near Pittsburg 907

— Explosion questions — Water In red-

150
804
377
•151
509

485
291
712

•246
1835
292

•692
418
•347

•80,
•810

413

'671

'623

183

150
•675
•215

454

51

j>63
843

hot boiler ; cutting In with un
equal pressures ; explosion of con
nected holler. Rockwell 411,
Mason 528. Ellethorn, Molloy,
Griswold. Cox 601, Hawkins 711,
Aldrlch 748. Clarke. Powers 784,
Thompson 828, Bendel
— Explosion, Scotch marine boiler, Mt

Clemens
— Explosions, Boiler, In England
— Explosions. England and America
— Feed regulator. Static
— Flow meter. Indicating, G. E.
— Flue, Cone — Collapsing strength
— Flues. Corrugated — Inquiries 452, 752. 787,
832, 87i
— Foaming boiler. G. K. E. 530

■ — Frozen plant, Starting. Case
— Gas burning. Glick
— Gas explosions in uptake, Preventing
— Give the gases room
— Graphite in boilers. A. .1. L.
— H. Hawes' b'iler laws. Hopkins
— Hangers, Suspending h. t. boilers

bv. Holder
— Head. Bumped. Designing. O. W.
— Heat available to steam boilers — •
Effect of moisture In air. Mor-
ley 109, 118. Scott 372. Moxey
— Heat transmission in boilers : expe-
riment with Inserted tubes. Rupp
•402, (Ton flues hottest) Sweet
— Heating surface and horsepower
— Heine boilers. Ayer mill
— House-heating boilers and furnaces.

Proposed basis for rating
— Inquiries on specifications : horse-
power : boilers for given engine ;
safe working pressure, etc.
— Inquiries — Sta.vboIts : joints
■ — Inspector, Recollections of. Norster
— Inspectors, Am. Inst, of 30,

— Inspectors disagree ; door ring
welded to leg ring. King, Terman
— Lap seam fractured. Edgett
• — Lifting water in boilers : cause of
explosions. Harden 216, 528. Me-
Mahon 414. 711, Boone 487, Leese
559. Terman 719

— Locomotive-boiler stresses. Bur-
leigh •622
— Log, 24-hour. Ward 705, Eezer 936
— Low-water — What to do 203
— Management — Deterioration. McGa-

hev. Beets 218, Case 373

— Manhole leaky : air pressure ^842

— Manning boilers. Feed-water en-
trance to 972
— Oil in boilers 418
—Oil, Lubricating. In boilers 938
— Oil tests. B. & W. marine boiler 170. 188
— Oilfields engineering — Plugs. Hartley 22
— Overpressure, Case of. Terman
— Piping. Improper. Binns
— Pitch at girth seam. C, G. F.
— Plugged boiler head. Walters
— Plugged boiler nozzle. Fagnan
- — Presstire. Sudden release of

— Priming of water tube boilers — Ele-

ments of circulating s.vstems, va-
rious types : Influence of steam
and water space, liberating sur-
face, water level. Maguire •428,
Parker Roller Co.

— Ranee boiler connections. Noble
•.t7."i, Howard

— Rating. New — Mechanical stokers 722.

-Redondo nlant •lOS. 224,

— Rendering boiler accident. New-
burgh

— Repair. Boiler room — Rods through
front head leaked : curved lining
for top of fire door : furnace
arches. Jahnke •441 Cultra fiOO.
Beneflel 602. Knight. Zanadke
•748. Rnv

— Repairs. Boiler, -Vuthorlty on

— Riveted loLnts. Nickel-steel. Tests
at rnlv. of ill,

— Robh-Brady Scotch boiler

— Safe boiler construction

— Safety In boiler room, Germany

— Saving of 40 per cent.

— Seam. Diagonal, EfDclency of

— Second hand boiler experience. Joy

— Self-cleaning boiler. Parkers

— Settings, Boiler. Brown

— Shell construction. Rotundity, not
type of Joint, the essential In

— Shock absorber. I'rew •440, Noble

— Smoke preventer. Waldron

— Soft water and scale

— Soot, Effect on performance — Tests
by Coughlln of Champion Coated
Paper Co.

— Steam drum to prevent wet steam.
Gilbert •254, Price 487, Sterling

— Stirling boilers. Detroit Edison's
Delrav station — Largest In world
— Tests. Jacobus •840,

— Strain measurements of boilers —
Tests at Providence. Howard

— Surface combustion. Bone •767, 787

— Test, Hammer, Value of 187

— Test, Hydraulic-hammer. Terman 128

— Test of large Stirling boilers, De-
troit Edison's 237

— Tests — Coal moisture. Blumen-

stein ^^*-.m

— Tube blowout. Dredge, Cayuga •83.';

— Tube bursts. Buffalo 798

935 — Tube failure. Redondo. Calif. ^907

— Tube-spreader tool. Heely ^387

• 795 — Tubes blown out, torpedo boats 686
128 — Tubes, Leaking, Trouble. Reimers
378 104. Beaton 375. Wright 414,

•850 Cultra 488. Beneflel 527, Chap-

•154 man 598. Fenwlck •786. Noble 971

• 111 — Tubes, Recent developments In test-
ing ; sulphur absorption, etc. Speller '91

— Tubes, Rolling. Kirlin 26, Sterling 184
— Vertical boiler horsepower. H. P. B. 416
— Water level, Change of W. B. L. 260

— Water-tube boiler advantages 111

— Wooden vs. steel boilers 403

Bolt. Broken, in gas engine •954

Potting, Pipe-flange 961

Bone. Surface combustion •767, 787

Book. Loose-leaf, habit. Knowlton 906

Books. Engineer's reference. Llghte

59fi. Bailev 783. Rivers 830, Herter 831
Books. Text. Mistakes in 299

Booth. Compounding steam engine 497

— Elec. drive for textile mills 519, 702

Borsig boilers. Welded 392

Boston anti-smoke law results. Baker 50
Boston. Power show at 97o

Brains. Importance of 110

Brake. Rope, for measuring power.

Smallwood '442

Brasses. Fitting. Gougstreet 443

Brewster factorv. Heating, ventilating '790
Brickwork, Drill for. Smith 24

Brine. See also "Refrigeration."
Brine. Calcium-chloride, Homemade

outfit to make. Kell ^898

Brine mixtures. H. J. M. 338

Brine. Nonprecipitation of calcium
chloride from, by ammonia.
Smith 958

Brine pipes. Porous. Burlev 681

Briquets from street rubbish. Euro-
pean 58
Briquetting tests. Bureau of Mines 94, t835
Bristol's ink type recorder '849
British Canadian Power Co. Bateman •886
British steam plants. Developments.

Seager '245

British thermal unit. Determining

value of. Smallwood ^164

Brockton school. Heating. Evans ^715

Brooklyn Polytechnic Institute 940

Brooklvn sewage flushing plant •SOO

Brooks. J. C Death of 194

Brown Boverie turbines. Junge '52

Brush. See also "Commutator"
'436 Brush holder. Controller. Marzolf •"SI

'369 Brush holder. Displaced. Altman
151 •2R8. Hill 520

'960 Brush setting. Interpole motor ^892

105 Inrushes, Rectifier. Setting. Meade ^14

417 Brushes, Kerosene, etc.. for. Desal,

Malone 306. Johnson •479. Hill 85 4

Buckeye gas engine ^817

Buckingham palace ventilation. Boyle •649

Buffalo exhaust fan. New •614

(874 Building. Office, plant power cost 241

Buildings, High, Hot-water beating.

267 Evans '925

900 Bulkley. H. W., Death of •798

297 Hunker. Plant oiling system •ee'J

Burdick. How engine was wrecked •474

*^ Bureau of Mines. Recent work 58, 93, 110,

•282. 584. •915

—Electrical section 213, 854

— Publications l5„i

Burleigh. Locomotlve-boUer stresses •622

• 78'> Busev. Proposed basis for rating

789 house heating boilers and furnaces •26»

Bushed the cylinder. Buflfum 524,

teSO Dixon 'gSl

• 76 Bushing, Loose, caused pound. Browne ovo

373

•436

600
416
•879

•263

491
566
369

637

July I to December 31, 1911

POWER

Cahall boiler circulating system
Calcium-chloride bo'lne. Homemade

outfit to make. Keil 'ggS

Calcium chloride, N'onpredpltatlon of,

from brine, by ammonia. Smith 958
California. Coal in 481

California power plant. Pioneer. Alli-
son •731. 252
California power projects 540, 833
Callan. Correcting back firing and
fuel waste In large producer-gas
engine plant 57
Calorimeter. "Wild's," Precision Inst.

Co.'s •389

Cambria Steel Co.'s flywheel •SOd

Canal tug boat. Producer-gas '593

Canton, Engine wreck at 723

Carbon dioxide. See also "Gas"
Carbon-dioxide gases. Experimenting

with. Williams 145, Anderson 375

Carbon dioxide in gases 789

Carbon-dioxide. Most economical

amount of. Bement •ISd

Carbon-dioxide recorder. Value of, and
boiler efliciencv. Vassar 69, 445,
rehling 258. S47. McAndrew 219,
Bumiller 25S. Bancel 336. 871,
Mowat 445. Wilhelm 644. Steely 905

Carbon-dioxide recorders. Connecting.

Rogers 'esg

Carborundum furnace refuse utilized 30

Carelessness in power plant. Chap-
man 292. Prew 671
Carnegie Co.'s gas engines ^17. 142.
178, 291
Carrier. Rational pyschrometric for-
mula
Case. Lockwood & Brainard olant
Casting. Engine. Repairing. Chapman
Catalog numbers. Changing
Catalogs, Writing for. Montague 639,

Utz
Catechism of electricity •700,

Caton. Operator's view. Diesel engine
Cement for glass oil cups
Central station "Block"
Central station. Ideal. Oakley. O.
Central sta.. Office-building, Los An-
geles
Central Sta. Steam Co.'s double ex-
pansion Joint
Central station vs. Isolated plant :
purchasing power, etc. Jackson

9, 286,
— ISO. plant held Its own. Page
— Profit as Item of powpr cost
— Security Mutual Life bidg. plant
— Cent.-sta. failure: Phlla. fire. Johns
— Why they catch business : sales
methods. Jackson 477, 904, Ellis
—Solicitor will not tell
— Alleged r.qtp discrimination. N. T.
— Various editorials, etc. 149, 150, 224.
713,
— \arIous discussion. Elmes. Cooper
28. Bailey 05. 377. 527. Baldwin
67. 413. ^562. Hayes 103. Thorn-
dyke 107. Johnson 147. McGahev
147, 1«5. 415. Rnshmore. Jack-
son. 179. 518. Schneider 221.
Sweetser 241, Trofatter 298, Dp
Wolf 327. Willis 337, Klermeler
•411. Blanchard
Centrifugal force and

Odell
Centrifugal force. Finding
Centrifugal pump. See

"Air." ef.
Certificates of quality 453

Chain block. "DlfTerentlal," puzzle.

Phillips nr,9, Stafford *H71

Chain tongs. Leak caused by. McOabey '24
Chance for a career 201

Chandler. Flywheel explosion. West

Berlin •344. 529. 674. 750

Charts. Steam. Excellent. Thomas •967

Chicago Edison — Power limiting react-
ances 59
Chicago rWer. Firing marine hollers •892
Chief and the governor. Phillips 460
Cbiers head, r.oin" over 150. Kimball

297. WIcKcs 330. Nigh 075

Chiefs pay. The 760

Chimney. See also "Stack."
Chimney. Concrete. I'ortland. Ore. •94*5

Chimneys 4S9

Chlmnev". Oscillation of 872

China. Engineers' wnges. Adams Sg."!

Christie. A. n. Developments In

prime movers •392. •OO"

Christie alrsteam engine, etc. ^382. 52''.

003. ^009. ^721. 934
ClnHnnatl— Plum st. generating sta. ^315
Cincinnati Trac. Co. "tstlon •313

Clndnnstl water works. Blake *S\n.

High record, etc. B]5, e.'io

Circuit breaker. Oil. tests, Chicago

E*II»on. Merrlam 59

Circulating wnter. See "Water."

"rondenscr." "Pomp." etc.
Circulating water. Auto. control.

Tlnghes •332

Circulator. I/^-ds •247

Clamp. Plston-handllng. Koppel'i •OW

Clamps. Vise. Noble •371

flywheels.

452.
"Pump."

P*GK PAGE

Clarinda, la., central station •542

•431 Clarke. Engine speed vs. economy •2'J7

Clayburn smoke consumer •246

•898 Clean or pretty clean 418

Clearance controller. .4ir-compressor •SOH

958 Clearance. Excessive. Effect of 605
481 Clearance in ammonia compressors.

Bonn 153

Clearance loss. Unnecessary. Klrlln 148

Clearance, Percentage of. A. L. J. 338
Clearance space. Unnecessary. Lyman 181

Clewell. Power-house lighting •SIS

Click in cylinder. Apparent. Perras 867

Clinker formation. Bailey ^802

Clinker. Water to prevent 929

Clippings, niing. Bancel ^295
Clutch. Friction, Baldwin & Co.'s

"Reilly" •388
Clutch. Friction, Disk. Stewart and

Kohlberg •144
CO;. See "Carbon dioxide." "Gas," etc.
Coal. Air required to burn 222
Coal. Alaska's, unlimited 114
Coal and ash conveyer, Jeffrey, at Erie '92
Coal-ash fusing temp. Bailey ^802
Coal. Approximate heat value. Hollo-
way 331
Coal cars. Unloading. Williams 496
Coal consumption. Producer-plant.

Rice 668. Rose, Lenoir 895
Coal crane. Special. Toledo ^398
Coal crusher. Jeffrev single-roll ^612
Ccal defined. Watson 25. Bement 219
Coal handling. Muncie. Whiting ^549
Coal. Heat units in 832
Coal. Heat units required to evaporate
moisture in. Blumensteln 144,
Horning 446
Coal in California 481
Coal. Lignite, for gas producers 211
Coal. Lignite, heat value 712
Coal. Pennsylvania production 772
Coal. Philippine, for home SOI
Coal preservation — Air exclusion 270
Coal purchase by specification 640
Coal purchasing under specifications
— Creciius, A. E. Ry. Eng. Asso.
report. Bureau of Mines 584
Coal. Rhode Island 678
Coal. Sampling. Rogers 774
Coal. Sampling and analyzing. Barr 482
Ccal scale. Richardson electric •eiS
Coal sprinkling scheme. Another 454
Coal tests. Bureau of Mines 93, 594, t835
Coal. The supply of 8
Coal. U. S. production of 738
Cobalt. Power company at •SSG
Ccchrane double feed heater •SSX
Cock. Gage, "S-C" •77
Coefficients of heat transmission. Allen 32
Cold losses through insulation. Mat-
thews 225
Cold-storage duty. Matthews 73
Collins. '•Engine-room inspection 620, 830
Colorado plants purchased 41
Colorado river power project 540
Colors of piping. Benjamin 49
Combustion. Incomplete. Loss due to 280
Combustion. Surface. In boiler •767, 787
Combustion — T'nderfeed stoking vs.

overburnlng. Woolson 901
Commutator bars. Filling pits 832
Commutator changes, rewinding gen-
erator ^740
Commutator lubrication. Desal. Ma-
lone 300. (With flax packing)
Johnson •479. Hill 854
Commutator mica. Grooving. Wamp-

ler 360
Commutator iifca. Undercutting, and

removing bad spots. Fox 326
Commutator. Pitted. Quirk repairs on
— rilling with dentists' cement.

Barnwell 555

Commtitator potential "explorer" ^892
Commutator. Sparking. Hawkins 666.

Scott 777. Jackson. White 893

Compound. Boiler, feeder. Dickson •293

ComtHiund tank. Concrete Kolfel •071
Ccmpound engine. See "Engine."
Ccmpressed. Compressor. See "Air."

".\mmonlB." "Refrigeration."
Compression nnd terminal pressure 71<
Cf»mpre*ipIon. Engine 972
Compression. Full, stops engine 872
Compression 'n ammonia compresaors 153
Compression In compound engines 200
Compression plant. Increasing capac-
ity of. Blflckstone 4.'5S
Compression — MIent running engines

224. 412

Compression unnecessary. Rlrlln •500

Concrete pipe lolnt. Skinner •707

Concrete. Helnforclng 549

Concrete compound tank. Koffel •071
Condensate from gas calorimeter. Heat

pqulvalcnt of R57

Condensation. Receiver. Swope 333
Condenser. Ammonia. Locating leaky

coll In. Sheridan ^75

CONDENSER. STEAM

Sep «l«o 'Air pnmn," "Pump."

— Cincinnati Trac Co s condensers — ■
Reveroing valve for circulating-
water flow : auxiliary air valve

900

'276

'640

71

831

'921
450
972
753
316

726

387

29
•84
lOG

043
604
677
30'J
723

CONDENSER, STEAil

— Condensers — Types ; safety 223,
(Jet condensers: preventing flood-

Ing of cylinder) Specht 487, Low 676

— Cooling system. J. A. D. 260
— Design of plants — Condenser selec-
tion, saving. circulating-water

calculation, tables, etc. Fischer 472
— European practice ; rotary air pumps.

Christie ^626

— Gage pipe. Clogged. Lamarlne 215
— Gain from using condenser. H. G. T 189

— Hoosac tunnel condensing ontflt "5

— Leblanc condenser and air pump ^48

— Lubricating pump, Condenser ^471

— Piping. Good, needed 299
— Redondo Beach condensing plant

•199, 224
— Retubed condenser ; bent tubes. Fe-

naun *48.S. Owitz 734
— Steam. How to condense, for dis-
tilling water. Eldred, Dickson,
Noble. Davis. Johnson 'eS, Perry,

Nottberg •147. Fagnan ^904

— Strode pneumatic packing tool •Sll
— Surface condenser. Failure of. Ft.

Wayne •920
— Surface condensers — N. E. L. Asso.

report 12
— Turbine condenser tubes ; connec-
tions to avoid electrolysis. Lasche,

Junge ^551
— Unusual condenser arrangement.

Kelstrup *933
— Water doing double service 864
— Wheeler "Rotrex" hot-well pump •SSO
Condensing chamber. Lubricator. Wal-
lace 23. Dickson 258, Hawkins
486. Carruthers 529
Cone. Collapsing strength of •111
Cone seam. Strength of. P. L. •370
Coney Is. power plant. Rogers •eiS
Confessions of engineer. Warren •808
Congre.ss of Technology papers 25. 57
Conn. River Power Co. plant ^124
Connecting rod. Cast wroughtiron ^697
Connecting-rod end shims 752
Connecting-rod hump caused pound ^902
Connecting rod. Straightening. Gilson •409
Connell's receiver and heater ^760
Consolidated Oas, etc., Co.'s wheel ex-
plosion '682
Consolidated safety valve ^462
Constant potential, all loads 301
"Continuous-current Machine Design."

Cramp tl9i

Contractor. Steam cost to. Loomer 484

Controller brush holder. Marzolf "781

Controller. Water tank. Goodlett ^902

Converters. Rotary. Tupner •852
Converters. Rotarv, Starting from do.

side. Freed ^554

Conveyer belt. Hinge-edge. Ridgway 'SSg
Conveyer. Coal and ash. Jeffrey, at

Erie ^92
Cookson heater. Improved '37
Cooley valve rotor •eSC
Cooling air of buildings hv mechanical
refrigeration. Tweedy ^820, Op-
hills 897
Cooling air valves by water ^254
Cooling gas engines. Leese •209
• 'ooling gpner:ilor with piped air ^252
Cooling hot liquor. Handley 0.80
Cooling tower. Los Angeles '354
Cooling tower. San Francisco ^838
Cooper-Hewitt lamps. Clewell •Sl.l
C(K)per indicator reducing motion •849
Copper-expansion diagram. Treeby •658
"Copper Handbook." Stevens tS74
Cork Inserts. Pulley •582, 888
Corliss. See 'Engine, Steam," "Valve,"

"Knockofr."
Cornell economizer. Ed. 30. Jackson

257. Harrington 298
Corrosion. Boiler. I'reventlng. In bitu-
minous gas producer plants. Geof-

frey ^481
Corrosion. Causes and prevention of.

Taylor •623
Corrosion. Hot-water heater. Hvde
524. Kennlcott Co., Owltz. Jack-
son 749
Corrosion. Method for overcoming 281
Corrosion of s'enm hollers. Dunham 07
Corrosion. Steam-turbine and condenser 12
Cost. See als,> "Central station." etc.
Cost accounts, Operating maintenance Oil
Cost of furnace upkeep 30. 259, 4«5
Cost of power house. Dixon 274
f'ost of power In New England mills.

RrlnckerholT 912
Cost of steam to contractor. Loomer 484
Cost sy'tem. Power plant. GUI ^70^
Costs. Elec motor power Jackson 518
Costs. Operating, gas. power plants 178
Cost". Opera'lng. Rnshmore s. Jack-
son 179, De Wolf 327
Costs, powerhouse const. Dixon 514
Cost". Relstiv, of continuously and
Intermlttcnlly operated refrigera-
ting pinnt". Ilerter 455
Cramn "Continuous current Machine

Design" ♦194

Crane. Engine room. Holly •Qna

Crane members. Stress In •508

POWER

July I to December 31, 1911

PAOB
Crane, Special coal, at Toledo 'SOS

Crane, World's largest, Klver Clyde 5'>

Crane's switchboard 'ITT, 327

PACK

•151

24,

972

22

643

•529
•707
•934

•212
182

783
•931
•395

•83S

•S76
CI 7
41«

28S
•404
867

260

•931
530

•281
595

•441

Crank-case compression
Crank disk, Drawing on. Fagnan
Crankdlsk reamer. Llvlng.ston
Crank-pin box, Babbitt In. .lohnson
Crankpln brasses, Fitting. Gou-

slroet
Crankpln brasses. Ride play in. Mc-

(Jahey '294, Bennett
Crank pin. Broken, Removing. Bless-
ing
Crank pin, Hot, Cooling. Hurst
Crank pin. Loose. Fltts 370, 905,

Taylor 602. Hawkins
Crankpln oiler. Ashworth

Wagner
Crank-pin pressure, gas engines
Crank pins. Loose, Pins in. Robinson

•103. Sweet 220, (.lack for putting

on) Beets •295, Bennett
Crank pins, lleplaclng. Baum
Crank shafts. Gas-engine. Broken
Crecellus. Coal purchasing n.S4 — Best

standard voltage and frequency

for 3-phase turbo alternators
Crocker-Wheeler "Itemek" transformer
Crosshead clearance. Close. Fagnan
Crosshead. Getting, off rod. Hodges

•294, Bennett
Crosshead pin, Hot. Itay
Crosshead pins, I,arger. Beets 371,

Cannell
Crosshead, Valve. Broken. Cultra
Cruse ejector form of stack
Current. Where it Is sold for 2V^ cents
Curtis & Curtis pipe threader
Curtis rub. Co. plant. Blake
Curtis Curblne. N. Y. Kdison's
Curtis turbines, Ayer mill
Cutoff and number of expansions
CutolT in slide-valve engine
Cutting out dynamos In parallel. Mc-

Kelway 214, Appleton
Cycles, Gas-engine. I'oole
Cylinder, Apparent click In. IVrras
Cylinder arrangements. Compound en-
gines
Cylinder, Bushed the. Butfum 524,

nixon
Cylinder. Cost, Working pressure In
Cylinder condensation. Superheat and
Cylinder, Cut, Experience with. Emrle
Cylinder head. Bottom, Removing.

Lambourn
Cylinder head. Broken. Running pump

with. Meyer
Cylinder-head explosit
Cylinder head. I*ump.
Cyllndor-head repair.
Cylinder heat losses.

•052, Stanwond n:i;, Stui
Cylinder, L. p.. Water in
Cylinder. L. p.. Water wrecked. Low

fifl9. .Tones
Cylinder lubricator. L. n. Klrlin
Cylinder lubrication. Tomllnson 396,

P^onwick
Cyllnderoil consumption tests. Heck

132. Fenuo
Cylinder oil — N. E. L. A. report
Cylinder oil, Saving. Blake
Cylinder-oil tests. Lange ^699, Vra-

denburgh
Cylinder ratio, Comp. engine — Table
Cylinder, Gas engine, steel wks.. etc.

•17. 142, 178
Cylinders. Gas-engine, Water-dam-
aged ^329

D

Dallett pneumatic boiler scaler ^347

Dalton's laws 3S3

nam. Austin. Failure ,of fi03, 678

Dam. Water-power, Keokuk. Kirlln •,359
Damper regulator. Sectional. Hughes •C-t
Damper signal light •SO

Daniel. Why cas supply failed 330

Dasbpot. Bates Corliss ^498

Davles. F. H, Consuming town refuse ^107
Davies' experience. Richards ^913

Davis, Peat In the TT, S, 636, ••OlS

Day, Diesel till engine 521

De Oroot, Pendleton generating sta-
tion 'SIS
De la Vergne engines 55,S, 855, ^894
Dean. Roller design 218
Decnrhonzing internal-combustion en-
gines 330
Decatur high-school bnlldlnp- ^342
Deertleld river, Il.vdrnelec. devel, 408
"Delaware." Stenming results of 87
Delbert, Prot-cting compressors •0,80, •3nH
Derv, The Isorbronous governor ^773
Design of steam-power plants. Fischer

•171, •275, 472
Design, Power-plant 340

Designing, Poor. Examples of. Kim-
ball ^965
Destructors for town refuse •107
Details, Know the 300
Detroit automatic stoker. Improved ^157
Detroit Edison's Stirling boilers •840, 863
Dewey Indexing s.vstem modified •298

in. Greylock Mills
repair
.Aden

Hellmann 'COl,
npf

418

711
375

•181
906

Diagonal seam. Efficiency of

Diagram, Indicator. See "Indicator.

DIagrammeter, Schlerbeck

"IJIamond" soot blowers •SO, ^347,

"Diamond." Steamer, boiler explosion

Dickie. Marine turbine-engine

Die stock. Emergency. O'lirien

Die stock. Stewart, Kohiberg

Dies. Pipe-threading

Diesel, Atlas, oil engine test

Diesel engine diagram. Caton •668,
Malcolm ^704, Munro, Vanderfeer,
Frith . ^ ^ *8o6

Diesel engine, Operator's view. Caton
450, (Practical points; smoke)
Low dC'

Diesel engine plant. Kirlln 2.J0

Diesel engines, European. Christie

Diesel engines. Nicholl

Diesel Engines. Recent progress. Junge

Diesel engines, Rome 558, Prussian
Ry. loco.

Diesel oil engine — Costs, etc. Day

Diesel — Oil-engine fever

DIITuser. Rotating, Novak's

Diman. Loss by incomplete combus-
tion

Discharge pressure. High, Cause of

Distillates. Low-grade, Attachment
for running on, St. Marys

Distilling water *G8, •147,

Dixon. Power-house cost

— Power-house construction costs

— Switchboard suggestions

— Engine and machinery foundations

Dome. What means the? Knight

Door ring welied to leg ring

Draft and differential gages. Small-
wood

Draft — Damper regulator. Hughes

T>raft gage, Homemade. Rice

Draft. Handling the. Dumar 03. Brown 183

Draft. Poor. Cotton •22, Hurd 185,
Scott. Howard 218. McGahey

Draft recording gage. Uehling

Drawing paper. Isometric. Henley's

Dredge pipe wears. Kirlln, Johnson

•499
•810
907
•843
»703
•040
•806
•778

•629
291
•243

561

•178
•904
274
514
519
547
•973

•238

•04
•780

220

Dreyfus. Steam turbine for future

work
Drill for brickwork. Smith
Drip s.vstem design. Notes on. Lisk
Drips. High-pressure, Enigne
Drive for small generators and pumps.

536

26
•592

Hoke ^251. Harvey
Drive. Spring. Tanis •700

Drying out flooded sub-station, Blake ^364
Duff ballbearing ,1ack •"O?

r>unston power station, Newcastle ^272

Dwelshanvers-Dery. Isochronous gov-
ernor •773
Dyer. Direct-current turbo-generators

larger than 500 k.w. 591

Dynamo. See also "Electricity."
Dynamo-elec. machinery used Inter-
changcablv as generator and mo-
tor. Hoke •251, Harvey ^592
Dynamometers, New types, torsion and

hydraulic. Amsier •381

E

Eccentric. Advanced. Effect of 301
Eccentric. Double, Corliss valve set-
ling 301, Hawk 550
Eccentric— Emergency oil controller ^250
Eccentric. Fixed. Hawkins 560
Eccentric, Oil groove in. McGahey •966
Eccentrics, Single and double 300
Economizer, l^'r.rnell. Ed. 30. Jack-
son 257. Harrington 298
Economi-iier manifold. Repaired. Bless-

Economizers — Vulcan soot cleaner '

Economy. Expensive. Morse
K( onomv vs. Fpeed of engines. Clarke '
Edge. Electric wiring •407. ^555, '

EfBciency engineers. Williamson 442,

Noble
Efflclencv of reciprocating engines.

Hellmann •CSO, ^952. Stanwood

937. Stumpf
Efliclency. Personal. Rayburn
EfTlclent machinery. HocUadav
Ehrhnrt. T.eblanc air pump
Elector. Steam. Prew
E.lector, Water, nomemade. Salmon
Elbow, Jefferson union

ELECTRICITf

See also "Transformer." "Bat-
tery." "Commutator." "Brush,"
etc,

— Alternating, Changing, to direct cur-
rent — Rotary converters and
motor-generators, Tupper

— Alternating-current dynamos. Meade
— Care and operation, brushes,
rings. 'jommutators. bearings,
belts, etc. •14. Work in parallel,
speeds, field excitation, synchro-
nizing, swilcbboard connections,
etc.

— .Mternators driven by waterwheels.
Parallel operation of. Dean's, dis-
cussed 130.

•59«
•292
•156

834

PAGE

ELECTRICITY

— Alternators, Small, Voltage troubles

in. Sprague "-

— Alternators. 2- and S-phase In par-
allel ; phase changing with three
transformers. Grove, S. H. Har-
vey •IC, Malcolm, A. L. Harvey •214

— ^Alternators, Trouble with. Fox 666,
Jackson, Smith

— American Inst. Eiee. Eng. conven-
tion, Chicago — Schuchardt and
Schweitzer on power-limiting re-
actances, Chicago Edison plant ;
Merrlam on oU circuit-breaker
tests ; Wood on cost of operating
West Jersey & Seashore R. R. ;
Eastwood on electric motor con-
trol ; Radley and Tatum on limi-
tations of rheostatlc control : Bar-
num on elevator control ; Robert-
son on sag of overhead wires, etc.

— Ammeter, Magnetomechanlcal

— Armature, 220-volt motor. Chang-
ing, to 110 volts. Cooper

— Bearings. Wear of, due to unbalanced
airgaps. Clapper

— Belt vs. elec. transmission. Jack-
son

59

•893

108

Bureau of Mines, Elec. section 213,

1835, 854

-Catechism — Incandescent lamps

rOO, •921
10

with blower.

■H91
•252
•384

•666

530

— Central station, Oakley, O.

— Circuits. Elec, Maintenance of — In
sulators. pins, poles, underground
lines, etc. Ryan

— Constant potential, ail loads

— "Continuous-cur. Machine Design.
Cramp

— Cooling generator
Biery

— Drying out flooded substation.
Blake

— Dynamo-elec. machinery used In-
terchang?ablv as generator and
motor. Hoke •251. Harvey

— Dynamo oil throwing. Curing

— Dynamo, Operating, as motor. C. F. J. _31

— Dynamo voltage. J. F. R. ""^

— Dynamos. Cutting out, from parallel
"service. McKelway 214. Appleton

— Elec, drive for textile mills. Booth
519. Jackson

— Elec. drive. Why It has not always
given satisfaction — Motors, belts.
bearings, wiring, cost of power.
Jackson

— Electrocuted by 250-voit current

— European developments — Switch-
boards, split commutators, insu-
lating compounds : SchaBfhausen
hvdroelec. plant. Christie

—Exciter. Belted. Ad,1usting. Lynch

— Fishing line and pheasant cause
trouble

— Frequency, voltage and speed

— Generator. D. c. Rewinding. Fenk-
hausen

— Generator. Failure of, due to
sw-inging open-circuit. Nichols

— Generator, turbine and pump out-
fit. Williams

— Generators. Turbine — Baker venti-
lating vanes

— Heaters. Elec. Current consumption
of

— Hoosac tunnel. Electrification.
Rogers

— Hydroelectric plant. Richmond

— Hydroelec. plant, Vernon, Tt., Gen-
erators, Transformers, etc.

— Hvdroelec. plants. Southern Calif.
Edison

— Kilovolt-amperes

— Lee T'^lee. Light plant. Clarlnda

— Lighting. Power-house Clewell

— Locomotive. Powerful. Oerlikon

— Motor. Bell single-phase

— Motor. Compressor — Sparking
commutator. Hawkins 666, Scott
777. Jack«on. White

— Motor frequ?ncv. Changing. C. W. .\

— Motor. Induction renairs. Fenk-
hausen — Stator windings : locat-
ing onen circuits, grounds, cross-
ed phases, short circuits : ex-
tra meter scale, etc, Fenkhausen
•631, Coil removal and repair,
insulation, etc.

— Motor. Induction, troubles. Nichols

— Motor losses and output. C. H,

— Motor pulley faces and belt speeds,
Nichols

— Motor, Selecting right one for Job
— Costs for various drives. Wll-
llston 520. Jackson

— Motor-turblne-pump outfit. La-

chlne
— Motors. Elec, Installing. Wat-
son

— Motors. Interpole. Operation. Fox

— Motors. Synchronous. Correcting
low power factor

627

•73i»
741
•482
•136
972

•162

•124

•352

16

•542

•813

702

664

591

31

554

3S4

-Municipal L. & P. Co. plai
Francisco — Current at 2^!

nt. San
cents

•96
83 S

July I to December 31. 1911

POWER

ELECTRICITY

— Xatl. Elec. Lt. Asso. — Prime mov-
ers
— Plum street ttatlon. Cincinnati
— Polarity. A reversal of. Dupr4
— Portland. Or^.. generating sta.
— Power delivered, line resistance,

current
— Railway-motor bearings. Maintain-
ing. Fuetterer
— Reading. Remodeled substation at
— Rotary converters, Starting, from

d. c. side
— Shocks, Eloc Precautions against
— South Africa. Elec. power in
— Squirrel-cage bars, Remedies for
loosening of. Fuetterer 3C6. Slegel
— Switch. Double-pole double-throw,

Pole sub.^titutes for. Farbing
— Switchboard. Easily built. McKel-

way. Harvey '177. Crane
— Switchboard suggestion. DIscon
— Three-phase circuits. Power and

current '.n. Poole
— Transmission-line calculator,

Adams*
— Turbo-alternators. 3-phasc, Best
standard voltage and frequency
for : table of transmission costs.
Crecelius
— Turbo generators. Direct - current,
larger than 500 k. w. capacity —
Westlnghiuse views. Dyer
— Two- and three- wire plans. Operat-
ing alternately on. Mercantile
Library birtg.. Cincinnati
— Unbalanced fields. Pavis
— Wiring, Practical points on: light-
ing, conduits, etc. Edge '-iO?,
•741. Roneter *aoo. Garlitz
Electrolysis. Condenser, Connections

to avoid
Elevating returns from coils. La

Padie
Elevator gage board and pi'mps
Elevator-plunger grinder. Klingloff's
Elevator system. Story building
Emergency and the man. Wilson
Emerson. Engine wreck. Canton

ENGINE, INTERNAL-CO.MBUSTION

See also "Gas." .
— Aeroplane engines
— American gas engine. The
— Atlas Diesel Engine test *

— Attachment for running on low-
grade distillates, St. Marys «
— Bnd wreck, small cause. Utz '
— Bearing pressures In gas engines.

I>>wls. Krssler *

— Blast-furnace g.TS plant. Carnegie
Co.'s. at Youngstown— Snow en-
gine test
— Buckeye gas engine '

— Canal tug boat. Producer-pas '

— Combined steam turbine and Int-

comb. engin*'. Thornycroft
— Compression. Crnnk-rase
— Cycle". Gas engine. Poole '

— Cylinders laniaged by water. Utz '
— Decarbonizing Internal-combnstlon

engines
— Diesel englnn costs, etc. Day
— Diesel engine diagram. Caton
•Wf. Mnlcolm •701. Munro. Van-
derteer. Frith '

— Diesel f'nglne. Operator's view. Ca-
ton 4r,o. (Practical points: smoke)
Low
— Diesel engine plants. Klrlln 290,

Xlcholl
— Diesel engines, Enropean. Christie '
— Diesel engines. Recent progress.

.Tunge '

— Diesel engines, Rome BSg, Prussian
Hy. loco.

— Exhaust gas heater. Bogert '
— Kihanst heating. Gas-engine
— Exhaust pipe. Mng. trouble. Del-

bert 2rn, Renshaw, Street B22,
Leese

— Flywheel wreck. Hagertv _ "
— Gns and Gaso. Engine Trades Asso.

30. 708. 040,
— Gas engine failures. Recent. Analv-

«ls of. Knowlton '

— Ofls engines. European. Christie
— Gas power costs. Rushmore. .Tackson
— Gas power In a mfg. establishment.
Van Dorn ft Diiflon Co.'s. Weber
— Oas-power plant operation. Parmely
— Gns power plants. Operating cost
— Gas power section. A. S. M. E.—
EipTlenc"" with larce gas en-
gines In sirel works and furnace
Slant" — DI"cn«"Ion by McConn,
tevens. T>IchI. Floerr. Freyn.
FrledlandT. Trinks •]?. 20. 142.

— Gas-power sec., A. S. * R. — Fer-

nnld on developments In 1011 :
Setz on oil engine's ■ Lent on cr.m
psrstlre fo«t» of oil and gas:
Fnnis on do'lgn constants of
small gaso. engines

EXGI.VE. INTERNAL-COMBUSTION

— Gas supply failed — Regulator tron-
12 ble •330

•315 — Gasolene In crank case. Beets 481,

592 Johnson 638

•942 — Ignition equipment. Gas-engine.

Beattie *210

832 — Ignition, Timing the. Pagett *S96

— Indicator diagram. Looped, and
252 late Ignitlcn. Parmely, Austin

•234 'BSfi. Munro •779

— installation of small stationary en-
•554 gines. Leese ^209

854 — Intake manifolds for multi-cylinder
62 engines — Hall's inconsistent en-

gine discussed. Leese 'oG

•520 — Jacket water. Heating shop with.

Hays •C'37

•660 — Marine turblie-engine installation •843
• — Oil engine, De La Vergne. Cost of
327 power. Pfieghar and Lockwood 855

519 — Oil engine, De La Vergne. test.

Towl •894

•775 — Oil engine, Dc La Vergne. at New-

buryport pumping plant. Tucker •'io*'
•155 — Oil-engine fever 434

— Oil engines, (?are of. Leese 634,

Rose 81:1

— Oil engines tor Brit, warships 557

590 —Oil. Heavy, engine. The. Nicholl 291
— Oil-power vessels. Power transmis-
sion on 261, Wentworth 451

591 — Pistons. Lightening. Leese 330
— Producer-gas engine plant. Large,

Correcting back firing and fuel
•325 waste in. Callan 57

637 — Producer-gas power plant. Small. In

woodworking shop. Honeywill 923

— Rathbun valve gear. Improved •85">

•741 — Rayner two-stroke engine •70.'^

— Remington kerosene engine '480

•551 — Sargent combined gas engine and

air compressor 'SSG

•495 — Starting gas engine with steam.

•85 Beach ' 142

•232 ^Stopped. Whv the enaines — Pres-
•723 sure regulator. Daniel 'SIO

48rt —Sulphur in gas, etc. 743. 896

723 — Vapor lock In fuel-oil feed-pipe.

Leese 291

— Yacht "Progress," Gas-power *1S9

ENGINE, STE.\M

378 See also "Cylinder." "Valve."

29 "Indicator." "Compression," etc.

•778 — Automatic engine. First Western

built. Woolson 914

•ITS — Bearing. Poorly designed. McGa-
•400 bev •559, (Fan englnel Bennett •829

— Brownsfleld mills. Manchester, Old
•447 beam engine at. Leese •613

— Casting, Boken, Repairing. Chap-
man •640
291 — Christie air steam engine •382.
•817 Schaphorst 52S. Ed. 603. Christie
•59.1 'fion. Lent 721. Sullivan 934
— Clearance loss, Unnecessarv. Kir-
809 lln 148
972 — Compound engine. Equal work In :
•404 tables of receiver pressure and
•329 cylinder ratio. Low •88
— Coinpound engines, Inquiries regard-
339 Ing 260
521 — Compoundlnz. Early Kngllsh. Booth 497
— Coney Is. power plant •«!«
— Corliss engine bell crank repair •0,"6
•856 —Corliss engine. Historic Centennial,

sold for scian 576

— Corliss engl'ie improvements. Bates ^498

667 — Corliss engine. Running, with one

steam valve. R'>nd 52."?. Call

291 'STO. Ball. Wescott. Clark 960

•629 — Corliss ren.-h-rod vibration. Nagle 68

— Costs. Relative, of turbine and en-
•248 gine plants HI"?

— Cross comp. tnglne. Starting 712

561 — Cylinder. L. p.. Water wrecked.
•056 Low 660. Jones 871

752 — Cyllnder-oII (onsumptlon ; friction
tests of P.uckeve and Straight
Line engines. Heck 132. Fenno .375

704 -Eccentric, nil controller for •255

•742 — Economy of <Tpan"Ion 605

--Fmergencv and the man. Wilson 4S6

957 — Engine room. Crowded. Fagnan 144

—Engine room log book Ranch 52.1

•054 — Engine runs with steam valves
629 closed: leakage. Lantz 371.

179 DIrk«on 4S.S. Cannell 700, Bene

nel 750. Vinson 034

B57 — Field engine performance '721

924 —Friction. Los" In. J. A. F 605

178 — Foundations. Engine, etc. Dixon 547

— Framo. Engine. Repaired Dean ^216

— firouling lM-dplate«, HoIIv 047
— Hamilton Corliss engine of S. P.. O.

ft S. J. Rv. Largest Corliss en-
gine on Pacinc coflot •7.14
178 — namlltnn Corliss valve gear 'S'S

— Hoisting engines. Rogers •OiS
— Horsepower of engine ISO 647. 938
— In'pectlon. Engine room. rolllns

620. Jones 830

Knock detector — Mopewell vlbraca-

0.39 tor •26')

ENGINE. STEAM

— Knocks. Engine. Locating. Mills
524. Chandler 710. Ranch 750,
Leese 783. Nottberg
— Lentz poppet-valve engine
— Less than 10 p.c. steam engines
— Lubrication. Steam-engine. Tom-

linson 396. 426. Fenwick
— Naval reciprocating engine. Renais-
sance
— N. Y. Pub. Library plant •

— Oiling system. Centra! engine-room,

Whitehall bidg., N. Y. •

— Performance. Expressing, accurately

— Philadelphia's oldest steam engine

— Wetherill & Bros.' •

— Pound, Hump caused. HafTord •

— Pound — Loose bushing. Browne
— Pumping-englne tests, Ariz. Rey-
nolds
— Pumping engine. Worthlngton high-
duty. Providence *
— (Juestion — Speeding with closed

throttle. Rtckwell 41. 601. 748. 784,
— Ray Consol. mines' 4-cyl. triple-
expansion Corliss engines •
— Receiver condensation. Swope
— Receiver pressure 567,
— Receiver pressure. Constant. Beard

26. Johnson
— Receiver pressure, equal loads
— Receiver pressure springs rods
—Reciprocating engines. Rfflclency of
— Wolf Locomobile and Stumpf
and other uniflow engines com-
pared : nrimary and secondary
superheating : heat losses In cyl-
inder, etc. Heilmann '659, •952,
Stanwood 937. Stumpf •

— Reducing valve In main *

— Reflectorscope for locating trouble
— Repair job. Crude. Creen

— Runaway — Closing throttle. Mc-

Eneanv 333.

— Scotch yoke. The. Beets
— Selection — "Types, floor space, pres-
sure range, steam consumption,
condensin,? gain, etc. Fischer '

— Sheffield Farms Co.'s plant '

— Silent running engines : compres-
sion 224. Lane
— Speed vs. economy. Clarke "

— Steam-consumption guarantees
— Steam engines and turbines — Com-
parative test — Westerfield '
— Stop and speed limit, Rockwell's au-
tomatic '
— Stops. Safety. Waldron ^24. Ed.

110. Noble '443, Stewart
— Stumpf uni'low engine. Kuhnle,
Kopp ft Kansch's -OS-. (EfB-
ciency discussed) Heilmann •659,
•952, Stanwood 937, Stumpf '

— Tests. Engine, Important — Valve
and piston tightness. Thomas
595. Brown
—Wolf locomobile '395. •659. 937. '
— WoodrulTBeach engine. Ancient '

— Wreck, Morganlown, Am. Sheet ft
Tin Plate Co.'s — Broken piston
rod
— Wrecked. Engine l)adly, at Canton.

I'merson
— Wrecked. How engine was — Broken

strap. ISurdIck '

Engineer and salesman. Phillips 616,

Wing
Engineer, Chief, anu governor
Engineer, Chief, 01)taining informa-
tion from
Engineer, Chief, or master mecbanic
Engineer, Coufessions of. Warren '

Engineer — Fspert advice
Engineer — Going over cblcf'g head
150. Kimball 297, Wlckcs 336.
Nigh
Engineer, Status of. Creen
Engineer. Veteran, and his engine
F.nginenr's exp"ilonce. Case
Engineer's license. Jimmy was refused
Engineer's npiiortiinlty. The
Engineer's place Is in engine room
Engineer's. Steam, experience with

gas power. Rose
Engineers. Various societies are In-
dexed under "American."
Engineers. A. <>. S. — Correction
Engineers. Am. Inst. Elec.. convention
Engineers. Am. Soc. Mech. — Oas-
power sec. 'n, 20, 142.
—Col. Meier's testimonial
—Thanks resolution, to British
— Annual meeting plans 834, 862,
Papers •.115, •804. 900. Pres.
Meier's address 007. sketch of
Pres. Humphreys •907, Pres.
Meier's portrait •008, Gas power
section
— New Haven meeting 855. 862,
Engineers. Efflclency. Williamson

442. Noble
Engineers. H,>w Empire State classes
Engineers, N. A. S.. conv'-nllon ^348.

Engineers. Ohio .Soc. .Mcri, 'so- K.14

950
865
•77
369

412

207
824

279

964

267
723
'474

23
262
808
788

675
S«4
276
873
401
4R3
340

178
•80
•81

602
150
501

'S88

POWER

July 1 to December 31. 1911

Ecglneei-8, Operating, Inst, of 41, 160,

345, 417. 454, 015. "98, 906,

Tliorne 66, Annual meeting 425,

Papers, etc. 396, 397. •402, 434, 4.j9.

•542, 600

Engineers, Scrub. Dickson 525.

O'ltegan 751

Engineers. Well Informed, Need of.

Hurley 483

Engineers. Writers among. Wester-
field 06, -.Vallace 107. Smart 14*
Elnglneers' experience with managers

555, .'■>99
Engineers' hours. Klermeler 143

Engineers' license agitation, R. I.

Mclnls 374

Engineers' license board, N. Y. 754

Engineers' license graft, N. Y. 961

Engineers' license law, Mass., revised 946
Engineers' license laws and e.\amin-
ers. Mass. Levy 184, 041. Smith,
Lyman. Foster. Chaddick 334,
Ironside. l..amarlne 373. Harris,
Pustun 563. (In Ohio) Hurd 602.
Vradenburgh 673, Lyman, Dixon 785
Engineers' license law. Condemns.
I-elpor 409, Gilbert 560, Blan-
chard 641, Howard 937

Engineers' license laws. Need of.

Hudson 106

Engineers' licenses — Quality certifi-
cates 453
Engineers' licenses, Taxing, etc. 262
Engineers' reference books, etc.
Llghte .')90. Hailev 783. Rivers
830. Krown 831. Knowlton 906
Engineers' wages 568. 824. Massey
751, Phillips 766, Mason. Orr 905.
(In China) Adams 885
Engineering articles, Filing. Bancel •295
Engineering caliber 378
Engineering judgment. Good 9'29
Engineering. Operating. Teaching 434
Engineering — "Trade" or "profession" 930
England, Boiler explosions, etc. 128. 378
•583. 650
Engll.sh power plant. Modern ^272
Ennls. The professional spirit 459
— Commercial water-power problem ^732
Equal work in compound engine. Low "88
Equalizer. H. K. C. 1S9
Erecting large flywheel. Holly 'SSI
Erie City boiler circulation ^431
Erie County IClec, Co.'s conveyer ^92
Erosion. I'ump-runner. James '526,

Johnson 676

Erwln. Lubrl.'ants at Panama 684

Escher, Wyss & Co.'s turbines •318, 339
Evans. Hot-water heating by forced

circulation •112, ^419

— Hot-water system and Inspection

troubles '492

— Fan system vs. direct radiation •569

— School heating •715

— Continuous vs. Intermittent heating 860
— Hot-water heating high buildings •9'25
Evaporation and condensation 679

Evaporation. Kquivaient. F. H. P. 70

Evaporation. Factor of. W. F. E. 647

Exciter. Belted. Adiustlng. Lvich •98

Exhaust outlet. Turbine. Design. Guv •257
Exhaust pipe. Long, trouble. Delbert

291. Itenshaw. Street .">22. Leese 704
Exhaust pipe size. Turbine. London

148. 415. 444
Expansion line. Wavy. Dickson, Low •lOi
Expansion tank. Overhead •494

Expansion. Temperature, diagram for

metals. Treeby ^658

Expansion. Linear, and temperature •164
Expert advice 788

Explosion. See also "Boiler."

"Wheel." "Turbine. Steam." "Cvl-
Inder head." Tinlng," "TilowolT."
"Condenser," "Mud drum." "Air,"
"Gas."
Explosions In England — Boilers 128.
378, Blow-oft pipe and stop valve
chests •SSS

Factor of safety In steam piping
Factory addition, Heatlug. Wake-
man
Factory, Heating, ventilating. NIcholI
Fagnan. A limelv rescue
Failures. Gas enslne. Knowlton
Fales. Reduction of lubricating costs

in smelter power plants
Fan. New Buffalo exhaust
Fan system vs. direct radiation.

Kvans
Farmlngton tiywheel explosion
Feed regulator. Boiler. Static
Feed water. Sec "Water." "Heater."

etc.
Feeder. Compound. Homemade. Dick-
son
Felt. Hair. Purchasing
Feltman's power plant. Rogers
Fenkhausen. Induction-motor repairs
•631.
— Rewinding d. c. generator
Ferrochem for feed-water treatment
Field engine performance. Lent

PAOE

I'illng engineering articles. Bancel •_295
Filing note-book materials, etc. 596, 783,
830. 908

Filter. Oil, construction. Bunker '663

Filtration plant, Cincinnati 'SIO

Fire extinguisher formula 832

Firebox, Loco,, Jacobs-Shupert. Beets 561

Fireman Davies' experience. Richards •913

Fireman Grlmaldl lost Job. Hopkins 686

Fireproof oil-storage house. Hays *697

nring boilers. Brown 333

I'lring marine boilers on Chicago river •692
I''ischer. Design, steam-power plants

•171, •275, 472
Fishing line caused trouble •l-'>
Fitchburg Yarn Co.'s costs 912
Flagg. Bureau of Mines' work _ 93
Flange, Broken, repaired. Leese 24
Flange. Welding a. Russell '826
Flanges, Pipe ^645
Flash point of oil. Finding. Pattern 'Oeg
li'loat. Glass, needle valves, Home-
made. De Sausaure '825
Float, Keg tank. Keli 5S9
Float pump control. Runion '706
Flooded system of refrigeration.

Bonn 226. Holloway 380
Floor space, f'ngine. Fischer •Ifl
Floors. Concrete engine-room, Paint-
ing. Ranch 560
Flow meter. Indicating, boiler. G. E. *154
Flue, Cone, Collapsing strength "111
Flue, Corrugated, collapsing pressure
452. 752, 872, Heating surface

789, 832
Flue gas. See "Gas," "Carbon di-
oxide."
Flywheel. Sec "Wheel."
"Forced draft." Maintaining voltage

by. Biery 252

Fort Wayne condenser failure ^920
Foundations, Engine and machinery.

Dixon 547

Foundations, Gas-engine. Leese ^209
Foundations — Grouting bedplates.

Holly 947
Foundations, Small machine. McGa-

hey •932
Foundations. Turbine. Lasche, Junge

•552. Smith 663 .

Fox. fndercurting commutator mica 326

— Operation .it interpole motors •■S91

Franklin Institute. The 34J
Fraser. Sampling and analysis of

furnace gas ^282
Freed. Starting rotary converters

from d, c. side ^554
Freezing, Prevent standpipe. Nichol-
son 411. Sullivan 563, Herter
601. Zetterlund 785, Noble,

Leese '82^. Speace 870

French. Manometer as lung tester •611

Frequency, voltage and speed 972
F'rlction clutch. Disk. Stewart and

Kohlberg •144

Friction clutch. Reiily •SSS
Friction-load diagrams, Smallwood's.

McGahey 108. Werner '186

Frost. Case of. Blair 681

I'rost. "Live" and "dead." Keil 74

Frothing storage batteries. Leese 366

Fuel feeder. Low-grade. St. Marys ^178
Fuel tests, etc.. Bureau of Mines 58. 93,

93, 110. 213, '282. 5»4. t835, •915

Fuels. Low-grade, for Diesel engines 250
Fuetterer. Maintaining railway-motor

bearings • 252
Fuller. Combined vacuum and grav-
ity-return heating system 'igo
Fuller's earth as oil filter 135
Funnel. Grooved the. Fenaun •705
Furnace. See also "Boiler." cross-
references from It. etc.
Furnace arches, Jahnke •441, Cul-
tra 600. Beneflel 602. Knight,
Zanadke •74S. Ray '782
Furnace. Bricking. Prew •670
Furnace-door baffle plates. Milled •sge
Furnace-door handle. Cook •746
Furnace. Oil, designs. Wayne •747,

Williams 'see
Furnace questions. Dixon, McGahey

67. Brown 183
Furnace — Took gases from uptalce.

Breckonrtdge •901

Furnace — T'nderfeed stoking. Woolson 901
Furnace upkeep. Cost of; using car-
borundum-furnace refuse. etc.

30. Howard 259. Sterling. Naylor 485
Furnaces. House-heating. Proposed

basis for rating. Busev •263
Fusing temp, coal ash. Bailey •802, 864

Gage cock, "S-C"

Gage-glass valves. Opening. O. G. G.

Gage class and water level. W. L. B.
151. Lyman

Gage classes. Putting In. Little,
Williams 221. •644, Bond

Gage pipe. Condenser. Clogged. La-
marlne

Gage. Steam, stuck. Wilkinson

Gages. Draft nud differential. Small-
wood

Gages. Steam, rtick — Have two

Garbage destruction. Davies

Gary, Gas-engine practice at

Gas. Blast-furnace, Clean

Gas-blower set, High-pres., Sturte-
vant, in Brooklyn and N. T.

Gas burning under boilers. Click

Gas calorimeter. Heat equivalent of
condensate from. Robinson

Gas engine. See "Engine, Internal-
Combustion."

Gas. Exhaust, heater, Bogert

Gas explosion. Ash-bunker

Gas explosion in engine expansion
box : producer arrangement

Gas explosions in boiler uotake. Pre-
venting

Gas Bred compressor plant economies

Gas, Flue. See also "Carbon dioxide."

Gas, Flue, analysis and CO2 record-
ers. Value of. Vassar 69. 445,
Uehling 258. 847, McAndrew 219,
(Some analyses on steamships
"Princess May," etc.) Bumiiler
258. Bancel 336, 871. Mowat
445. Wilhelm 644, Steely

Gas, Furnace — Incomplete combus-
tion

Gas, Furnace, Sampling and analysis.
Fraser, Hoffmann'

Gas, Nat.. Heat units in

Gas power in a mfg. establishment.
Van Dorn & Dutton Co.'s. Weber

Gas-power plajts. Operation. Parmely

Gas-Power Section, A. S. M. E. — Gas
engines in steel works '17, 29,
142. 178. Operating costs of gas-
power plants 178. Fernald on de-
velopments in 1911, Setz on oil
engines. Lent on comparative
costs of oil and gas. Ennls on de-
sign constants of small gaso.
engines

Gas power. Steam engineer's experi-
ence with. Rose

Gas-power yacht "Progress" equip-
ment— Engiue ; regulator of
steam supply to producer ; mix-
ture controller, etc.

Gas-pressure regulator trouble

Gas-producer and engine develop-
ments. European

Gas. Producer, canal tug boat

Gas-producer (apacity with lignite.
Biucher

Gas producer. Effect of varying steam
supply — Tests at Univ. of Birm-
ingham •99, 109,

Gas producer, Grine crude-oil

Gas-producer investigations. Bareau
of Mines 58, 95,

Gas-producer plants. Bituminous,
Preventing boiler corrosion In.
Geoffrey

Gas-producer plants. Suction, Points
in operation. Woolman

Gas producer plant coal consumption.
Rice 668. Rose. Lenoir

Gas. Producer, power plant. Small, in
a woodworking shop. Honeywill

Gas production. Peat for. Davis"

Gas samples. Apparatus for passing
to calorimeter. Berry

Gas, Sulphur in. Oiafseri 743. Jack-
son

Gas supply failed. Why. Daniel

Gas-supply line. Check valve In

Gas-turbine problem, Suggested solu-
tion. Blalsdell •367. Malcolm,
Knapp

Gas volumes. Chart for reducing, to
standard conditions

Gases. Give them room

Gases. Took, from uptake. Brecken-
rldge

Gasket. See also "Packing."

Gasket cutter. Johnson

Gasket punch. Bentiey

Gasket repair — Know the details

Gasket. Duplex Akron metallic

Gaskets. Everybody's Invincible steel-
asbestos

Gaskets, Fitting. Beneflel

Gaskets. Tarred-paper. White. 255,
Mason

Gasolene In lubricating oil and crank
case. Be;^ts 481. .Johnson

Gassifying crude oil. Grine

Gathering them in. Thorndyke

(Jear. Marine reduction, Westtnghouse

Gears. Annular and spur

Gears, Cloth. General Elec.

Gears. Pitch diameter of

Gearing for high speed

Gelpke. "Hvdraulic Turbines"

Gelser automatic check valve

General Elec. Co. — Correcting low
power factor with synchronous
motors

— Indicating holler flow meter

— Cloth pinions

Generating sta . Portland. Ore. West

Generator. See "Electricity."

Geoffrey. Preventing producer boiler
corrosion

Germany. Steam turbine in. Junge
•52. •466. ^510. Guy ^257.

PAGE

•167

13

905
280

939
328

>4S1
329
895

'901
■827

452
'614
338
53,1
f974
'539

July 1 to December 31. 1 9 i I

POWER

Gill. Power-plant cost system

Glafke oil burner, Improved

Glass. Cement for

Glick. Burning gas under boilers

Going. "Industrial Engineering"

Golden-Anderson valve

Goulds centrifugal pumps

Goulds pumps 'ISS,

Government research work (See also

■Tnited f>tates")
Governor, Adjusted the. Livingston
Governor — Brass washer trouble
Governor, Chief and the. Phillips
Governor, Elevator-pump automatic
Governor gave faulty regulation.

Ironside
Governor. Jabns engine and turbine,

Massey Machine Co.'s
Governor. Pumping-engine. KJeruIff
Governor repair job. Sterling
Governor size. Corliss engine
Governor, Sulzer. Oil-operated
Governor, The isochronous. Dery
Governor weight. Inertia. W. G. W.
Graft 678. Chase 871. Rayburn. Will-
iams. Scarborough 935, White,

Adcock
Graft. License. In X. Y.
Graphite as scale preventive
Graphite reduces oil consumption.

Blnns
Graspit belt dressing
Grate and safety valve area 151, 222
Grate. Auxiliary, in Germany
Grates. Shaking. Kobb Co.'s McDonald
Graver Tank Wks.' water purifier
Green Fuel Economizer Co. "Heating

and Ventilating"
Greens temperature pendants
Greenwich Cold Storage Co. explosion

683,
Griffith. New use for deep-well pump
Grinder. Pluns-!r-rod. Klingloll's
Grlne. Gassifying crude oil
Grine crude-oil gas producer
Grossman shoe-factory plant
Grouting bedplates. "Holly
Guarantees. Impossible
Guard. Machinery. Colton
Gutta Percha & Rubber Mfg. Co.'s

packing
Guy. Mean pressure. expanding

steam
— Turbine exhnustoutlet design

H

Hackenberg turbine

Haeerty shoe factorv wheel wreck

Hair felt. Purchasing. Westcott

Hamilton-Corliss engine. Oakland

-—Gravity valve gear

Hamilton Series ■N" power pump

Hammer test. Value of

Handicaps of the studious

Handle. Fur.nace door. Cook

Handley. Cooling hot liquor

Hangers. Suspending h. t. boilers bv.

Holder
Harmon feed-water purifier
Hauck oil burning outfit
Hays. Heating with jacket water
— Fireproof oil-storage house
Head. Humped. Keslgninr. O. W.
Head loss in plpfs. Pnchc
Heads. Thermal and static. Matthews
Heat available to hollers : loss bv

hnmldlfv. Fd. 10!). Morlev 118.

Scott .172. Moxey
Heat energy. Velocity from
Heat feed water. Bleeding receiver to

2m. Peik. Webster 44.''.. F. R. L.
Heat from different Illuminants
Heat loss to a'^hplt. C. M. R.
Heat transmission In boilers. Rapp

PAGE

•703

t974
•685
•499
•612

110
•826
•708

460
•729

597
811
452
•392

T>etermlnlng. Small-
utilization, Diesel e

•402. Swopt
Heat unit valu.

wo^td
H'at. Waste.

gtnes
Heater. See also under "Heating and

vent."
Heater and receiver. Connell's
Heater. Cochrane double feed
Heater. Cookson. Impvd.. Bates Mach.

•910
947
604

•597

685
•204

120
>742
>746

299
'746

680

'386
'667
'697
111
'134
'606

599
821
301

800

•IH4

•248

feed-water.

Co.'
Heater. noti'ile service

Hoppes

Heater. F^xhnnst gas niixlllnry. Bogert
Heater. Feed-water. Homemade. All-

com
TIeafer. Harm in feed water
Heater. Hot water, f'orrnslon. Hvde

524. Kennlcott Co.. Owltz. .Tack-
son
Heater. InexpAnslve Fn'hhangb
TIeater. Keep It clean. Wallln
Heater. No relief valve on. Ford
Heater. Onen. fldvantflge« of
Heater. Open, connection Improve-

mento niTon
Hi-aier. Water, problem. Rice
Heaters. Feed water, Open and cloned.

AdTanta«»». O, C. H. 111. Cnl-

tra

749
441
r.23
410
111

Heater. Water, Homemade. Noble

•791. Russell •967

Heating water from exhaust. Noble ^903
Heating water with steam from Cur-
tis turbines by special valves •878

HEATING AND VENTILATION

— Air velocities, Measuring. Hechler

•341, 861

— Bogert exhaust-gas heater *956

— Boilers and furnaces. House-heat-
ing. Proposed basis for rating.
Busey •263

— Buckingham palace ventilation.

Boyle •649

— Circulation through heating colls,
Improving — Receiving tank.
Rathman •ne

— Cold water lu returns caused pump

to pound. Howard 650

— Combined vacuum and gravltv-re-
turn heating system. N. Y. Trade
School. Fuller •igO

— Connecting high pres. drips to heat-
ing mains. Enigne 26

— Continuous and intermittent heat-
ing: PowoU's data at Waterbury.
Hastings. Evans 860

— Cooling air In buildings 820, 897

— Corrosion of hot-water heater 524, 749

— Elec. heaters, Current consumption

of 972

— Elevated returns from coils •495

— Engine jacket water, Heating shop

with. Hays ^667

— Exhaust steam. Curtis Pub. Co. '579

— Factory addition. Heating. Wake-
man •643

— Factory. Brewster, Heat and vent.

Nicholl •793

— Fan system vs. direct radiation.

Evans ^569

— Heat-transmission coefficients — Ta-
bles for iron radiators, painted
radiators, fan heater colls, etc.
Allen 32

— Heater, hot-water system. Bingham-

ton ^87

— "Heating & Ventilating." Green

Fuel Economizer Co. t874

— Heating - system Improvements.

Dixon ^266

— Heating & Vent. Engineers. Chicago

meeting 'llS. 192. •263, •342

— High-school building. Decatur,

Heating and ventilating. Lewis '342
— Hot water heaters. Piping. Howard
267, (Range boiler practice) No-
ble ^375

— Hot-water heating by forced circu-

lation ; cccnomlcs of same at

Lackawanna R. R. terminal.
Kvans ^112. ^419

— Hot water neating high buildings.

Evans •923

— Hot-water system and Inspection

troubles. Evans ^492

— Humidifying system trouble. Mor-

ton •gso

— National Dlst. Heating Asso. 32
— N. Y. Public Library heating plant.

Blake •837
— Radiator trouble. Thomas' •34, ^117
— School hea'lng. Steam and hot-
water. Evans •713

— Siphon. Homemade. D.nnner •861
— Temperature pendants. Green's •964
— Thermic valve. Stickle •rjl
— Vapor pump troubles. Cllnehens 649
— Ventilation. Compulsory, Legisla-
tion on

— Ventilation. Macy's store.

— Water hammer. Hudson

— Waten heatnrs. Homemade •791. ^967

--Water heat-r problem. Rice ^861

— Water vapor In air 899

— Westlnghouse automatic bleeder

turbine ^198

Hebard. C. W.. Death of •834

Hechler. Measuring air velocities

•341, 861
Heck. Cvllndcr oil consumption tests

132. Fenno 37."!

Heely holler tube spreader tool ^387

Hellfnann. Kmclcncy of reciprocat-
ing engines •n.'iO. 937 •930
Heine holler circulating svslem ^429
"Hendrlck's Commercial Register" tS3s
Herr. F^lwln M. •270
Herter. Relative coots of continu-
ously and Intermittently operated
refrigerarlng nianis 433
High school liuildlngs. Heating and

ventilating. Lewis •342

Hill pump valve

Hitchcock. Superheated steam tents
Hoffmann. Sampling and analysis of

Quay

fur

gn«

Hoist, niffer'ntlal. piuir.le. Phllllns
669.
Hoist. Mine. Rav Consolldaled's
Itolsf". Steam. Fsing compressed air

In. Richards
Hol«tlng engineer. Tom Hunter: types

of hoists Rogers

•70

•8RS

•282

•871
•733

475

•948

Hoke. Dynamo and motor Inter-
change •251, ^392
Holloway. Cent, pump capacity and

speed 508, 751. 93G
Holly. Erecting large flywheel ^884
— Notes on grouting bedplates 947
Hone.vwlll. Producer-gas plant 923
Hoosac tunnel. Electrification. Rog-
ers • 2
Hooven. Owens. Rentschler pump •IJS
Hopewell vibracator •269
Hopkins. Lubricant made good •303
— Hiram Hawes' b'ller laws •613
— Fireman Grimaldi lost job 686
Hopkinson-Ferranti valve ^393
Hoppes double-service heater '3iG
Horsepower. See "Power." etc.
Horsfall's destructor •167, ^168
Hose. High-pres.. Repairing. Dennis ^132
Hot box. See also "Bearing."
Hot boxes and cures. Sterling 220
Hot-water heating. See "Heating."
Hours. Engineers'. Kiermeler 143
Howard. Strain measurements of

boilers •845
Hudson. Water hammer, heating sys-
tem •64S
TTughson. G. F.. Death of 194
Iluhn flexible metallic packing ^614
Human element. The 262
Humidifying system trouble. Morton ^932
Humidity. -Mr : Carrier's psvchrometer 899
Humidity. Heat loss due to 109, 118,

372. Moxey •436
Humphreys, Pres. A. S. M. E. '907
Hunter. Tom. hoisting engineer. Rog-
ers ^948
Hvdraulic dynamometer. Amsler ^363
Hydraulic-ram nuestion. F. K. P. 70
Hydrocarbons. Origin of. Becker 12
Hydroelectric. See also "Water,"

"Turbine. Water."
Hydroelectric development. Pacific

Gas & Elec. Co.s 252. ^731
Hydroelectric developments' — Mont. ;

Vt. • 408

Hydroelectric plant, Vernon, Vt. ^124

I-beams. Cast-iron. Size. W. H. W. ^679
Ice. See also "Refrigeration."

Ice, Clear, without reboiling. Bonn 303

Ice machines. Changing. C. I. M. 647

Ice plant. Repairs to. Carr 898

Ice-water system. Air in. Herter 304
Ignition equipment. Gas - engine.

Beattie 210
Ignition. Late, larmcly, Austin •636,

Munro ^779

Ignition, Timing the. Pagett ^896

Illinois Glass t o.'s explosion 185
Illinois Trac. Co.'s turbine explosion

194. 224. '227. 372. 414, 60J
Illinois T'nlv. tests of heating boilers

and furnaces •263
Inches. Circular and square. O. K. 31
Inconsistent engine discussed. Leesc •GO
Indexing engineering articles — Modi-
fled Dewey system. Bancel "295
Indicate, register and record 646

INDICATOR. STEAM-ENGI.VE

-Connection, Accurate — Rack. Van
Brock

-Cord lock knot. Croom

-Diagram advice wanted. Bullard
443. Prescott

-Diagram defects. Parker

-Diagrams - Compression unneces-
sary. KIrlln

-Diagram. Diesel-engine,

Caton
•668. ^704.
-Diagram. Indicator. Frvant '226.

Robnett. Chase. Appleton
-Diagram. Negative loop In
-Diagrams — Faulty regulation.

Ironside
-Diagrams. Friction-load. Small-
wood's. McGahey 10S, Werner
-Diagrams from unbalanced engines.

Carruthers
-Diagrams. Frvant'a — Wavv expan-
sion line, Taylor ^633. Prescott
•676. 870. Mover
-Diagrams. Indicator. Flits
-Diagrams — Reducing valve In main
Diagrams. Wants, explained. Poarch

•293.
-Diagrams with one Corll

•560

856

445

•872

•708
•186
•565

valv

324.

DlagrammetT. Schlerheck
-Rxnanslon line. Wavy. Dickson.
TiOW
Gas-engine diagram. Looped, and
Jale Ignition. Parmelv. Austin
•636. Mun'o
-Lanra contlnnniia diagram
-Reducing motion, ronper Co 's
-Reducing mntlon. Homemade. Lyon
-Reduclng-rig errors. LIbbv
-Vlhratlons. Indicator pencil Tay-
lor •635, Prescott ^676, 870.
Moyer

•.849
•361
•206

10

POWER

July 1 to December 31, 191 1

Induction-motor repairs. Fenkhausen

•631, »6ai
Induction-motor troubles. Nichols ."JOl

"Industrial Engineering." Uoing t9T4

"Inertia" Corliss valve gear •498

Inertia of air-compressor intake.

Kedlleld *24L'. Leese '808

Information, Obtaining, from cbief.

Piper 23

Ingcrsoll-Kand air compressor •30.'>

Injector suction pipe. Misplaced.

Potter 23

Injector valve. Automatic, Shar-

wood's '500

Inspecting power-plant apparatus 71

Inspection, Engine-room. Collins 620,

Jones 830

Inspectors disagree. King, Terman '25

Installation of small stationary gas

engines. I.eese •209

Institute of Operating Engineers 41,
160, 345, 417, 454. 015. 79!?, 906,
Thorne 66. Annual mefting 425,
Papers, etc. 306, 307, •402. 434,

459, '542, 600
Instruments, Recording, for small

plants. Bailey 65

Insulating compounds, Impregnation

with 628

Insulation, Cold losses through. Mat-
thews 225
Intake manifolds for multi-cylinder

engines. Leese '56

Interpole motors. Operation. Fox •SOI

Invincible steel asbestos gaskets 013

Iron, EfTect of superheat on 471

Iron expansion diagram. Treeby •eSS

Iron. Telling wrought from cast 75, 183
Iron. Wrought, castings •697

Isolated plant vs. central station ;

purchasing power, etc. .Tackson 9, 2S(i
— Iso. plant held its own. Page 22

— Profit as item of power cost 29

— Successful isolated plant. Hayes 103

— Cent.-sta. failure ; Phila. Are,

Johns 106

— Opportunity — Longacre Co.'s offer 22-i

— Isolated-plant management. Tro-

fatter 298

— Ideal cent, sta., St. Oakley, O. 310

— Iso. plant practice ; gage records.

Kiermeler ^411

— Why central stations catch iso.
plant business Jackson 477, 904,
Ellis 643

— Victory — Siegel Co. stores 723

— Iso. plant owners responsible.

Blanchard 933

— Various editorials 149, 150. 300. 604,
677, 713, 753
— Various discussion. Elmes. Cooper
2.S. Bailey 65, Baldwin 67, 413.
562. Thorndvke 107. Johnson 147,
McCahey 147, 185. 415. Rush-
more. Jackson 179. 518. 67,5,
Schneider 221, Sweetser 241,
Crane 327. Bailey 337, 527, 'Wil-
lis 337
Isolated power for making shoes.

Wilkinson 910

Isolated power plant, Interesting.

Rogers •84

Jack, Ball-bearing, Duff ^797

Jack. Screws, Effective pressure 752, 'O'l

Jackson. Notes on purchasing power 9

— Central sta. vs. iso. plant 179. 286, 327.
477, 643. 675, 904
— Why elec. drive has not always

given satisfaction 518
— JacobsShupert firebox. Beets 561
Jacobus. Stirling boiler tests '840, 863
Jahns engine and turbine governor •461
Japanese navy Turbines for *3Sk
Jefferson unlo.n elbow •loB
Jeffrey single-roll coal crusher •612
Jimmy was refused license. Terman 401
Johns-Manvllle piston-rod packing •499
Johnson. L. M. Novel commutator lu-
bricant ^479
Joint, .\mmonIa, Opening. Kell 381,

I'agnan 'eSO
Joint. Double expansion. Cent. Sta.

Steam Co.'s •387
Joints. Butt and strap 56G
Jones. Comparative economy of satu-
rated and superheated steara 10
Joy. Second-hand boiler experience 509
Judgment. Engineering, Good 929
Junge. Steam turbine In Germany.

•52. ^257. ^466. •SIO, ^550

— Recent progress, Diesel engines •248

K

Kaiser. Operating alternately on 2-

and 3-wlic plans ^325

Keil. "Live" and "dead" frost 74

Keokuk. Water-power dam. Klrlln ^359

Kerchove unlflow engine consumption ^952
Kerosene. See also "Engine, Int.-

Comb."
Kerosene a protection to pipes and

pumps. Scott 4S2
Kerosene for brushes. Pesal 366. 854

Kershaw. Smoke abatement Gt. Brit

Kessler, A. .J. Bearing pressures in
gas engines '

Keyed piston trouble. Wlnton '

Keyway, Locating, in Corliss valve
stem. Klrlin 180, Johnson 414,
Ilawklns

Kieffer. Lnallned shafting 553,

Kllovolt-amperes

KIngsland shops' heating

Klrlln. Diesel-engine plant

— Water-power dam, Keokuk

Klle-Klte pulley covering

Kllngloff's plunger-rod grinder

Knight. What means the dome?

Knocks. Engine, Locating. Mills 524,
Chandler 710, Kauch 750, Leese
783, Nottberg

Knocks. Loose piston causes. Brock-
man

Knocking, Air-compressor. McGahcy

Knockoff plate. Wooden

Knorr. Pulleys for high-speed belts

Knowledge is power

Knowlton. Recent gas-engine failures

Kootenai falls. I*ropo.sed development

Koppel's pision-handling clamp

liorting tests of tar fuel

Kuhnle. Kopp & Kausch Stumpf en-
gine

Labor, The dignity of

Lachine. Can., Installation at "

Lackawanna R. U. terminal heating

•419. Shop heating '

Lamps, Incandescent — Catechism •700, ■
Lamps — Power-house lighting *

Lampson Lumber Co.'s plant
Lange. Cyl.-oil service tests 699,

Lanza continuous diagram ■

Lap. Inside. Effect of. H. T. C.
Lap seam fractured. Edgett
Lasche on turbine practice '

Laws. License. See "Engineers." "
Lea pressure recorder '

Lead. Sheet, prevented bearings from

heating. Bentley
Leak. See also "Tubes," etc.
Leak. Ammonia condenser. Locating
Leaky Corliss valves 371, 488,

750,
Leblanc air pump. Ehrhart
Lee Electric Light plant '

Leeds circulator '

Leese. Intake manifolds for multi-
cylinder engines
— Installation of small stationary en-
gines '
— Frothing of storage batteries
— Passing of another veteran '
. — Steam-pipe explosion, England
— Care of oil engines 634,
Lent. Field engine performance '
Lentz poppet-valve engine
Letter heads. Using firm's 639,
Lewis. G. W. Bearing pressures in

gas engines '

Lewis. S. R. Heating and ventilating

high-school buildings '

Llbby. Reducing-rig errors
Library. N. Y., heating plant
License. See "Engineers.' "
Light, heat, power, ice f'ant. Olson
Lights. Heat produced by different
Lights, Incandescent — Catechism ^700,
I,;ghting of power stations
Lighting. Power-house. Clewell
Lighting, Wiring for. Edge
Lignite. Producer capacity with.

Blucher
Lignites. Heat value of. L. R. D.
Link motion. Homemade. Little
Lisk. Design of drip system
Liverpool boiler explosion 862,

Locomobile. Wolf •39.5, (Efficiency)
Heilmann •esO, •952, Stanwood
937. Stumpf
Locomotive-boiler stresses. Burleigh
Locomotive. Logging — What means

the dome? Knight

Locomotive tubes : treatment.

"Locomotive Water Columns,

ance to Flow through."

and Enger

Locomotive wheel diameter ;

PiGK PAjE

918 Los Angeles aqueduct, Power devel-
opment. Allison ^473
•417 Los Angeles, Grlne producer at *743
•561 Los Angeles office building *726
Los Angeles — Southern Calif. Edison '.352
Loss due to Incomplete combustion 280
Low, F. R. Equal work, compound

engine •SS

Low, H. B. D'esel-engine operation 667
•500 Lubricant. See also "Oil," "Bcar-
290 Ing," "Commutator."
•359 Lubricant, How it made good. Hop-

812 kins •503

•232 Lubricants at Panama canal. Erwln 684
•973 Lubricating costs in smelter power

plants. Reduction of. Fales 426

Lubricating material. New 807

830 Lubrication. Efficient 531

• Lubrication. Steam-engine. Tomlln-

440 son 396, 426, Fenwick 711

•902 Lubrication — Step-bearing pump. Lynn •ISS

•403 Lubrication, Turbine-valve. Vlnnedge •217

691 Lubricator. Attaching, to steam pipe 605
149 Lubricator condensing chamber. Wal-
•954 lace 23, Dickson 258. Hawkins

408 Caruthers 52»
•964 Lubricator connection. Auxiliary.

250 Livingston •671

Lubricator, L. p. cylinder. Klrlln ^598

•685 Lubricator. Mechanical. Richardson '268
Lubricator. Sight-feed, Wire In.

Sobolewskl •598, Johnson •780

Lucke. "Power" ^974

Lung tester. Manometer as French •fill

30 Lynch, Veteran engineer •27-?

•384 Lynn, Step-bearing pump at •133

stroke
Locomotives,

tunnel
Loewenstein,

Oil and elec..

Speller
Reslst-
Talbot

piston

Hoosac

Centrifugal Pumps"

tl95.
Log book, Engine-room. Ranch '

Log sheet. Dallv. Mobile. Klrlln '

Log, 24-hour. Ward 705. Kezer 936,

Case
"Logarithms for Beginners." Pick-
worth
London, W. J. A. Turbine pipe sizes

148. 415,
— Prime movers for auxiliaries
London pumping station. Van Brussel '
Longacre L. & P. Co.'s offer
Loomis-lVttibone producer op. costs
Loose-leaf book habit. Knowlton

921 M

813

923 McCormlck turbines, Vernon. Vt •121
906 MacCoun. Gas engines, steei wks.
796 'IT, 142, 178

491 McDonald shaking grates •761

037 Macintire. Absorption kink 153

5.50 — -Advantages of superheated steam *281

— Power from compressed air 698

873 Machinery guard. Colton •597

Macy store ventilation, yuay 'll^

105 Maffei-Swartzkopf's Wks.' turbines •466 .

Maguire. Priming of w. t. boilers

•75 *42S. ^674

709, Maintenance of elec. circuits. Ryan 97
934 Maintenance, Operating, expense ac-

•48 counts 611

'542 Making good 490. Watson 105
'247 Manager gets experience. Klrlln 555,

Kimball 599

•56 Management of men. Griffitli 69

Manchester smoke-abatement confer-
'209 ence 918
366 Manhead, Eyebolt for. Lee 867
'619 Manhole. Arm drawn into ^842
650 Manifold. Economizer, Repaired.
819 Blessing •746
'721 Manning boiler : boiler design 218
•78 Manometer as lung tester. French •Oil
831 Marine engineering. Problems of 149
Massachusetts boiler rules 223. 228
'447 Mass. license laws. etc. Lew 184.
641. Smith. Lvman. Foster. Chad-
'342 dick 334. Ironside. Lamarine 373.
'206 Harris, Pustun 563, Vradenburgh
'857 673. Lyman. Dixon 785. (Revised) 946
Master mechanic or chief engineer 202
'542 Mathematics. Engineering 824
821 Mather, Robt.. Death of 686. ^723
'921 Matthews. Cold-storage dutv 75
490 — Water cooling 152
'813 — Cold losses through insulation 225
'407 — A\t cooling and moisture precipita-
tion 379
211 — Thermal and static heads and flow
712 of heat and liquids •60S
'143 Mauler. Redondn Beach plant •igS, 224
'129 — Southern Calif. Edison system •SS?
940 — Office building central station, Los

Angeles •726

Meade. Care and operation of alt.-

'950 cur. dynamos ^14

'622 — A. c. generators In parallel "174

Mechanical equivalent of heat ^164

'973 Meier's, Colouel. testimonial •SO. ad-

•91 dress 907. portrait •90S

Meldrum simplex destructor •109

Melms & Pfennlnger turbine •46(>

tSl Mercantile Library bldg. Cincinnati ^325

Mercury column. .Adjusting. Marier

452 •52fi. Mueller. Mowat •7t!>

Meter. Indicating boiler flow. G. E. ^154

•3 Meter. Water. Velocity. .Anderson •IS?

Metropolitan substation, Reading "234

415 Miller. Thermodynamics Problems t<574

523 Milne superheater *M6

410 Mine hoisting engines. Rogers '948

Mine^power pinnt. Cobalt •SSff
971 Mine power plant. Modem. Wither-
bee. Sherman & Co.'s. Stoltz.

tSl Shaplra •688. •764

Mine-power system, Ray Consol. Tup-

444 per •73.">

610 ^finnesota. Water resources of 2^i>

652 Modern Sclen"e Club program 26T

224 Modern tendencies 78S
179 Moisture in air. Heat loss due to 100. 118.
906 372. •43«

July 1 to December 31, 1 9 1 1

POWER

Moisture In coal. Heat units required
to evaporate moisture in. Blu-

menstein 144. Horning 446

Moisture precipitation. Matthews 370

Moneymalilng by engineers 201
Monnett. Cliicago smolie inspector 230.

•463, 'figa
Moore. Air-pressure effect '842
Morgantown, Engine wrecli at 267
Morlev. Available heat to steam boil-
ers 109, 118, 372
Morrisville. Vt.. municipal plant 834
Motor. See "Electricity." "Engine.
Internal Combustion," "Water,"
"Waves." etc.
Mount Cli-mcns boiler explosion '"iSS
Moxey. Heat loss due to humidity 486
Mud-drum explosion, Kocliester 'SSS
Mullnn and Wichrawski's steam gen-
erator '77
Multiplicity of heads 645
Muncie coal-handling plant •549
Municipal L. *.- r. Co., S. F. •838
Municipal ownership opportunities.

Koiner 433

Municipal plant makes money 834

N

National A. S. E. convention '348, 501
National Dist. Heating Asso. 32
National Elec. Light Asso. 12
National Gas. & Uaso. Eng. Tr. Asso. 3D.
798, 940, 957
National Tube Co.'s gas engines 19
Naval reciprocating engine. Renais-
sance 87
Navy — Power of Atlantic fleet 772
Navy. U. S.. Turbines in 377
Needle valves. Homemade glass float.

De Sausaure *S2^

Nernst lamp Catechism •9;J1
Nerve. Required. McEneany 333,

Stewart 670
New England mills. Cost of power In.

Brinckerhoff 912

New York classes engineers. How 150
New York Edison Co.'s adv. John-

— Alligod rate discrimination

— Big Curtis turbine

New York Engine Co. — Bogert heater

New Y'ork license board

New Y'ork license graft

New York Public Library heating

plant. Wake
New York Trade School. Heating
New ^"ork water powers
New Zealand s water power
Newburyport. Oil engine at
Newcastl''-on Tyne power plant
Newcomb. R. E. Air receiver explosion
Niagara power statistics .552

NIcholl. Heating and vent. factor.v
Nichols. Pull.-y faces and belt speeds

for motors
— Induction-motor troubles
Nobel Klesel engine
Noiseless Corliss valve gear. McGa-

hey •2.1-,. MIstcle 44H. Watson
"North Dakota" steaming results
Northern Calif. Power Co.
Novak's rotarv pump dilTuscr
Numbers. Changing
Nut lock. Adjusting. Blnns

•857
•100
930
650
558
•27a
663
741

G44

h7

833

O

Oakley. O.. qeneratlng sta.

Ocean waves. Power from. Van Win-
kle

Odell. Centrifugal force and flywheels

OlDce hiilldInK central station, Los
Angelps. Maujer

Ofllce building plant power cost.
Rweetser

Ohio So<. .M. E. •802, 834,

Ohio State University tests

Oil. See also "I.nbrlcnnts," "Petro-
leum." "J^nglne, Internal-Combus-

tinn."

Oil and gas costs

Oil burner. Glafke. Improved

Oil hiirnlne outllt. Portable. Haurk

on burning. Story building

Oilcan stand

Oil consumption. Graphite reduces.

HInns
Oil controller. Emergency. Cassldy
Oll-coollng tank for engine
OH. r'rnde. Effect of temperature

change on gravity of. Lyons
OH. Crude, pa^ producer. Orlne
on. Cnid". Gasslfylng. <;rlne
Oil cup. Loos • pulley. Am Specialty
Oil-cup vent juard. Frnnklln
on. CvllnrtT. consumption tests.

Heck I. ■?•-'. Fenno
Oil. Cylinder, for hot bearings. Mc-

Leod
on. Crllnder— N. F. L. A. report
on. Cylinder. Saving -Removing from

sepnrntor to barrel. P.lako
on. Cylinder, tested for actual service.

Lange •0!I0. Vradenburgh
on drip pan*. Roy

940

•700
•3SH

747
•74.1

.128
•2tt9
•700

•IRT
006

Oil. Emulsifled. Removing from water.
Sage 397,

Oi; extractor. Crawford '

Oil filter. Fullers earth as

Oil-filtering system. Hartford

Oil, Finding flash point of. Pattern

Oil-fired Parker boiler efficiency

•544,

Oil fuel

Oil fuel. Burning. Pattern

Oil-fuel, burner. Stllz

Oil-fuel burning. Hamlin. Wagner
1U7. 671 (Furnace plan wanted)
Steiner •70S, Lapsiy. Blair

Oil fuel. Crude. Notes on — Properties
of Calif, oils. Wade

Oil-fuel teed pipe. Vapor lock In.
Leese

Oil-fuel heating and alarm system.
Hartley

Oil fuel. Sulphur In. Olafsen 743,

Oil-fuel test, ii. & W. marine boiler

170,

Oil furnace designs. Wayne ^747,
Williams '

Oil grooves. McGahey '

Oil in boilers

Oil in exhaust steam

Oi; In Wyoming

Oil. Kerosene, for pumps. Scott

Oil. Lubricating, denosits. Loebell

Oil, Lubricating. Gasolene in. Beets
481. Johnson

Oil-power vessels. Power transmission
on 261. Wentworth

Oil pumps. Convenient '

Oil-storage house. Fireproof. Hays '

Oil storage tank indicator '

Oil tanks. Filling. Warner 255. 751.
Hawkins. Cox. Malloy 412. Buder
•444. Lane 9iS5. (Installing tanks)

Oil throwing. Curing. Long '

Oils, Heavy, Properties of

Oils, Mineral. OuterbridL'e's test

Oiler. Crank-pin. Ashworth ^524,
Wagner '

Oilfields. Engineering In. Hartley

Oiling kinks — Ring on can spout ;
wiper arrangement. Wilhelm '

Oiling system. Central engine-room,
Whitehall bidg.. N. Y.

Oiling s.vstem. Practical power-plant.
Bunker '

Oiling trouble. Turbine. Jones

Oily waste cleaner. Logie "

Olafsen. Sulphur in oil or gas 743,

Old. old question. The

(llson. Light, heat, power. Ice plant '

"Olympic" and "Titanic"

One-sided. On bein^. Johnson

Open circuit. Swinging. Failure of
generator due to. Nichols

Operating. See also "Cost," "Engi-
neers." "Engineering."

Operating maintenance expense ac-
counts

Opbiils. .\mmonla absorption refrlg.
system

— Cooling public buildings

Overpressure, Case of. Tcrman •

568

188
638

'3S9

730

291

•03
896

188

866
936
418

451
471
697
839

666
744
387

062
409
638
896
262
542

Pacific Gas & Elec. Co.
Pacific Light & Power Corp.

also

•198,
297,
PIs-

"Gasket

out. Prevented,

Rings

Packing. See
ton." etc.

Packing blowing
BiTtrand

Packing. Ctitting over wooden man-
drel, etc. Sanders •ISS, Colton

Packing. How to cut. vJllbert

Packing. Iluhn flexible metallic

Packing Job. Dimcult. (^okhr

Packing. JohnsManvlIle "Seo
automatic piston rod

Packing. Piston-rod. Cox •

Packing ring reinforcement, Unusual.
Fries

Packing. Should engine builder furnish?

Packing stulllng box. Ibach

Packing tool. Condenser. Strode

Packing. Trli>lo she<'t. Gutta Percha
& Ruhher Mfg. Co.'s

Painting engine room floors. Itauch

Panama canal. Lubricants at

Pan.nmn Pacific Exiiosltlon

Paper gaskets. White 2."i5. Mason

Paragon Paper Co. explosion

Parallel. Alternators in. Meade

Parallel operation of alternators driv-
en by watnrwheols. Dean. Jack-
son. KImhnll. Oscanva. Reed,
Iloltzai.ple. Cultra 136. Nute

Parallel servlrn. Cutting out dynamos
from. Mf-Kelwav 214. Appleton

Parallel. 2- and ."l-pha'e alternators In.
Grove. S. fl. Harvey •Ifl. Mal-
colm. A. L. Harvey

Parker boiler circulation diagram

Parker boiler. Southern Pacific's ^544.

Parker. J. W.. et al. Flvwheel explo-
sion. West Berlin 159. 1«7. •344.
074. 750.

Porker's. T. P.. self cleaning boiler

ISO
440
614
670

8S5

r.ao

6S4
76.'?
487
349
'174

Parmely. Gas-power plant operation 924
I'arsons. Growth of marine turbine •303
Pasadena municipal lighting plant 540
Pawling. Alonzo. Retirement 270
Peak-load troubles. Overcoming, at La-
chine, Can. ^384
Peat bogs. America's 636, •gi"
Peat in the U. S. Davis 'OlS
Peat Society convention 306
Pendleton generating station, Kinks

at. De Groot •31.f
Petroleum. Crude. Peterson 211
Pfleghar. Oil-engine power cost 855
Phillips. Chief and the governor 460
— Salesman and engineer 516, 674
— The chief's pay 766
Pickworth. "Logarithms for Beginn-
ers" tSl
Pins in loose crank pins. Robinson
•103. Sweet 220, Beets ^295, Ben-
nett '529
Pinions. Cloth. General Elec. •eu
riper. Farmington Flywheel explo-
sion •737

PIPING

See also "Heating and Vent.,"
'"Valve." etc.
—Accident. Fatal, at Scranton S62
— Ayer mill plant — Spring support for
30 in. exhaust pipe ; counterbal-
ance for 10-ln. steam pipe "882
—Bends. Pl|>e 863
— Bender. Pipe. Justus •805
— Bolting, Pipe-flange 961
— Brine pipes. Porons. Burley 6S1
— Chain tongs. Leak from. McGahey '24
— Colors of piping. Benjamin 49
— Direct branch pipe connection —

Table for taps. Taylor ^255
— Di.scharge pipe. Pump, pressure •638, 870
— Discharge through 24-in. pipe , 605
— Drip system. Design of. Llsk ^129
— Elbow. JclTeison union ^156
— Explosions. Piping. in England
•.■iS3. (Fatal steam-pipe explo-
sion. Leigh spinnln.g mills) Leese 050
— European steam-piping practice •394
— Exhaust pipe. Long, trouble. Del-
bert 291, Renshaw, Street 522,
Leese 704
— Fitting, Pipe — Valves : flanging ;

bending, etc. Conklin 440

— Flange, Broken, repaired. Leese 24
— Flange dimensions. Standard. D.

F. D. 200

— Flanges. Pipe 045

— Good work needed In piping 299

— Head, Loss of. In pipes. PochC "134
— Heating mains. Connecting hlgh-

pres. drins to. Enigne 26
— Hot-water heaters. Piping. Howard

267. Noble '575

— Improper boiler piping. Blnns •309
— Joint. Double expansion. Cent. Sta.

Steam Co.'s '387

— Joint. Pipe. Concrete Skinner "707

— Pipe and fitting tester. Chambers ^104

— Standpipe freezing. Preventing 411. 563.
001, 785, ^828, 870

— Steam and exhaust pipe sizes 111

— Steam pipe. Bare. Condensation 752

— Steam piping. Factor of safety 532

— Steam piping. Itock drill 605
— Steel vs. Iron pipe In refrigerating

work : bursting tests. Ball 960

— Tlireading die stocks ^040, •705

— Threading dies ^806
— Threading machine. Motor-driven,

Curtis & Curtis •79
— Turbine steam- and exhanst-plpe
sizes. London 148, Treeby 415,

Nellson 444

— Union for tank cars. Dunn •745

— Vibration prevented — Note 217

— Water In nower-plant pining 339
— Wear. What causes Kirlin's dredge

pipe to'? Johnson 218

— Wedged pipe In place. Bettrand '598
Piston. Compressor, Wire In. Mur-

dock 745
Piston fit. Taper. Brady 596, Camp-
hell 750
Piston-handling damn, Konpel's •9H4
Piston. Keyed, trouble. WInton •."61
Piston. Loose, causes knocks. Brock-
man 440
Piston packing. Leather •809
Piston ring reinforcement. Fries 211
Piston rings. Snap. Measurements 280
Piston rings. Tight. Ilandley •295,

Bennett 521)

Piston rod packing. Cox •581
Piston-rod packing. Johns-Manvllle

"Sea" Rings antomallc •408
Piston rod. Separating, from cross-
head. Hoflges ^204. Bennett ^520
Plolnn-rod swnb. Lanebein ^442
Piston rods. Receiver pressure springs.

Glodell 21,'5

ruion rod«. Removing Hawkins •700

Piston speed. High. Advantages of 301

Pi«ton stroke and wheel diam.. Loco. 45'i
Piston lightness tests. Thomas 505.

Brown 830

12

POWER

July I to December 31, 1911

Pistons. Gas-engine, In steel works —
Steel formula for rods ; water
connections, etc. '17. 142, 178

Pistons. lylghtenlnR. Improves flexl-

blllt.v and aeciOcratlon. Leese 330

I'ittsbui'K water supply. Increased 349

Planlmeter — Sclilirbctk IJlagrammeter •499
Plant. See "Isolated," "Power,"

"Stoam." etc.
Plugs, Kuslble. J. C. O. 222
Plugged boiler head. Walters '966
Plugged boiler nozzle. Fagnan 10.5
Plum street generating station •31.5
Plunger-rod grinder, KUngloff's ^232
Pneumatic lift on valves. Sobolewskl •8(J7
Poch^. Loss of head In pipes ^134
Polarit.v. A reversal of. DuDr(5 502
I'ollshihg round brass and steel. Mil-
ler 8G7
Poole. Gas-engine c.vclcs ^404
— Three-phase circuits •775
Port opening unequal. Mueller •74>}
Portland, Ore., generating sta. West '942
Potblvn. Pump noctor. Watson 438,
Cultra .-16.'!. Ellethorn •(!41, Staley
042. Clin'jhens 649, Howard 650,
Watts •96S
Pound. Hump caused. IlafCord •902
I*ound. I>oose bushing caused. Browne 595
Power. See also "Central station," etc. 29
"Power." Lucke 1974
Power Co.. British-Can. Bateman •886
Power cost, OfDce-bulldlng plant.

Sweetser 241

Power costs, Klec. motors. Jackson 518
Power cost in New England mills.

BrlnckerholT 012
Power delivered, line resistance, cur-
rent 832
Power factor. Effect of, on driving en-
gine 872
Power factor. Low. with synchronous

motors, Correcting '96
Power. Horse, of engine 189, 647. 93^

Power, Horse — Rating heating boilers '263

Power house. Cost of. Dixon 271

Power-house lighting. Clewell *813

Power houses. Const, costs. Dixon .Til
Power-plant betterment. Hunt, Cox

25. Bailey 374, Chapman 748

Power plant. Coney Is. Rogers •filS

Power plant. Curtis Pub. Co. Blake •n7S

Power-plant dOFign 340
Pcwer plant. Modern mine. Wlther-
hee. Sherman & Co.'s. Stoltz.

Shapira *688, •764

Power-plant records necessary 713
Power-plant show vs. efficiency 490, 710, 935

Power-plant supply analyses 5GS
Power plants. Steam, design. Fischer

•171. ^275. 472
Pcwer. Purchasing, Notes on. Jack-
son 9, 286

Power Specialty soot blowers •SO,

•347, •sro

Power stations. Lighting of 490

Power to draw up grade 301

Prairie Pebble Phosphate Co.'s plant 290
Pratt. Teaching operating engineering 434
Precedent ISS

Precooling plant. Santa F6. Allison •75ri
Pressure. Mean, of expanding steam.

Chart for. Guy ^204

Pressure recorder, Turnall-Warlng

"Lea" •87.'?

Pressure. Suction, change. Wanchope ^75
Pressure. Sudden release of 417

Pri'ssure. T'nhalanced — Question. J. S. ^70
Price watcr-currrnt motor ^208

Prime mover. New, Tesla's ^496

Prime movers. Developments In.

Christie •392, •623

Prime movers for auxiliaries. Lon-
don 610
Prime movers. Notes on 12
IVlmlng of w. t. hollers. Maguire

•428. Parker Boiler Co. ^674

"Princess May." Fluegas analyses on 258
Problem In statics •69,i

Producer. See "Gas." "Engine, Inter-
nal-Combustion."
Professional spirit. The. Ennis
Professor. One on the. Mann
Profit as Item of power cost
"Progress." Gas-power .vaeht. equip-
ment
Providence,

gine
Psvchrometrlc

Carrier
Piilloy and belt Inquiries
P\illpy arrangement. Poorly designed
PuUny covering, KIle-RUc '
Pulley faces. Mnlor. Nichols
Pulley lathe. Makeshift. Little
Pulley. Loose, oil-cup, Am. Specialty
Pulleys and belting
Pulleys for high-speed belts. Knorr
Pulleys. Transmitting capacities of:
tests : materials : cork Inserts ;
friction coefllclents, etc. Saw-
don •582, Whitcomb (Cork Insert
Co.)

459
183

High duty pumping en-
formula. Rational.

PUMP

See also "Air," "Oil," etc.
— Air and steam-bound pump. Staley 642
— Air chamber, Emergency. Leesc ^781

— Air chamber. Pump. S. L. W. 491

— Air in suction pipe. S. C. A. Ill

— Brooklyn sewage flushing plant •800

— Centrifugal - pump capacity and
speed. Holloway 508, Hurst 751,
Wheeler 936

— Centrifugal-pump repair. Heath •967

— Cent, pump. New, Tesla's ^490

— Cent, pump with closed discharge 530

— Cent, pumps. Capacity of 647

— Cent, pumps, Goulds •493

— "Cent. Pumps." Neumann. Loewen-

stein. Crissey tlOO, Angstrom 415

— Cincinnati water works. Blake
♦310. High record for continuous
pumping, etc. 015, 650

— Circulating pump and reversing
valve : dry-air pump and auxiliary
air valve •313

— Circulating-water control. Hughes •332
— Cold water in returns caused pump

to pound. Howard 650

— Cushion. Duplex-pump. D. P. G. 530

— Cylinder head. Broken, Running

pump with. Me.ver •216

— Deep-well pump. New use for —

Pumping from river and raising

water. Griffith ^585

— Dimensions for given delivery. H.

D. P. 376

— Drive for small generators and

pumps. Hoke •251, Harvey '592
— Dry-vacuum pump air-discharge

valves, water-cooled. Bertrand ^254

— Duplex pump steam consumption 789

— Duty of pumping engine. D. P. E. 491

— Elevator pumps. Los Angeles ^728

— Emergency pump arrangement '507
— Erosion, Pump runner. James

•526. Johnson 676

— European boiler-feed pumps ^394
— Experience. Centrifugal dredge

pump. Heath 411

— Flange, Welding a. Russell ^827

— Float pump control. Runlon ^706
— Goulds high-pres. triplex-plunger

pump •612

— Goulds piston pump. Air cylinder •ISS

— Governor, Pumping-engine.' KjerultT '672

— Ice-water .system. Air in 304

— Leather piston packing •809

— Lift. Suction. Chart for. Treeby ^637

—Lift. Hight of. H. P. L. 647
— London pumping station. Van

Brussel ^652

—Mine outfit. Goulds, at El Oro 68S

— Motor-turbine-pump outfit. Lachlne •384
— Oil engine. De la Vergne. at New-

buryport pumping plant. Tucker 558

— Oil. Kerosene, for pumps. Scott 482
— Packing blowing out. Prevented.

Bertrand ^708

— Packing. Piston-rod. Cox •SOI

— Pipe. Wedged, in place. Bertrand 'SHS
— Pittsburg. Allis-Chalmers pumping

engines •349
— Plunger-pump discharge regulation.

F. G. J. 376

— Potblyn. Pump Doctor. Watson

438. Cultra 563 (Pump trouble)
Ellethorn •641. Stalev 642. Cline-
hens 649. Howard 650. Watts •968

— Power pump. Hamilton Series "N" •ISS
— Pressure in pumn discharge pipe.

Murphy •638. Hawkins 870

— Problem. Pumping — Engines slow

down as head decreases. Crockett 932
— Pumps and calculations. Swingle 244

— Pumping engine. Saving effected
with — Measuring by-pass valve
opening. Salmon *l^

— Pumping-engine test. Ariz. ^932

— Regulator. Boiler-feed pump. Maver ^484
— Regulator, Step-bearing pump. Ber-
trand •8GC
— Repair. Temporary — Cylinder head.

Blom. ^745

— Richmond, Va.. pumping plant ^162

— Rotary numps. Increasing efficiency

of — Novak's rotating ditfuser.

Tupper »sr,G

— Rotrex pump, C. H. Wheeler •SSn

— Scale in suction pipe. Hartley ^333

— Screw pump. The. Johnson. Mason ^27

— Slush pump. Blake-Knowles •S.Sfi

— Snow dunL^x-pump valve setting 938

— Step-bearing pump. Auto.. Lvnn •IHS
— Strainers. Double, for pipes' •SOS
— Stroke-recorder. Potter's "Addlsto-

meter" •154

— Suction pipes g7,s
—Tank valve and float. Little ^145
— Telltale. Pump. Wllhelm ^442
— Turbine, generator and pumn outfit.

Williams •432

— TTnusunI pumping set — Terrv tur-
bine, pump and generator unit ^576
— Vacuum in suction pipe — Whv will
air pump, but not boiler-feed
pump work? Watts •ggS
— Vacuum Increased bv reducing ro-
tary-pump speed. Brown 23

PUMP

— -Valve crank. Makeshift. Wagner ^526

— Valve, Pump, Hill ^79

— Valve repair. Makeshift 103
— Valves, Rubber, Truing. Fams-

worth •746
— Vapor-pump troubles. Cllnehens 649
• — Worthlngton pumping engine. Provi-
dence •385

Qua.y. Ventilation. Macy store
Questions for discussion, Rockwell

411, Mason 528, Ellethorn, Mollor,

Griswold. Cox 601, Hawkins 711.

Aldrich 748, Clarke, Powers 784,

Thompson 828, Bendel

R

Radiator. See also "Heating and Vent."
Radiators give trouble. Thomas,

Banks, Mappett, Noble, Edwards,

Swope ^34, Dixon, Cox, Handley,

Dolphin ^117

Radiators. Shutting, indoors or out ^210

Railway, Elec, operation costs — West

Jer.sey & Seashore. Wood 61, 514

"Railway Shop Kinks." Wright t835

Raise. How he got a. Schlndler 'gee

Rate discrimination 677

Rathbun valve gear, improved '855

Ray (Jonsol. power plant •735

Rayner two-stroke engine ^703

Reach-rod vibration. Nagle 6S

Reactances, Power limiting. In large

stations. Schuchardt and Schweitzer 53
Reading, Remodeled substation at ^234

Reamer, Emergency. Livingston ^780

Receiver and heater, Connell's •7C0

Receiver, Bleeding, to heat feed

water 203, Peek, Webster 445,

F. R. L. 599

Receiver condensation. Swope 33.3

Receiver pressure 567, 789

Receiver pressure. Comp. engine. Low 'SS
Receiver pressure for equal loads,

Hawley's approximate rule 173

Receiver pressure. Constant. Beard

26, Johnson 221

Receiver pressure springs rods. Glo-

dell 215

Record, Cost, system. Gill •768

Record — Dally log sheet 'ilO

Record, Indicate, register 646

Record — 24-hour log. Ward 705, 936, 971
Records, Power-plant, necessary 713

Recorder. Bristol's ink-type •849

Recording instruments for small

plants. Bailey 65

Red core in Ice, Preventing. Brons-

torpf 153

Redfield. Inertia of alr-comprcssor

Intake •242, •868

Redondo Beach plant. Extension.

Alauier *198, 224, Performance

at plant. .-Mias 297

Reducing. See "Indicator." "Valve."
Reeves automatic adjustable valve ^231

Reflectorscope, New ^77

REFRIGERATION

— Absorption kink. Macintire 153

— Air cooling and moisture precipita-
tion 379
— American Soc. Refrig. Engineers 958,
959, 960
— .\mmonia absorption refrigerating

system. Ophiils 302

— .-Ammonia-compressor clearance. Bonn 153
— Ammonia compressor. Protecting
— Safety valve : telltale on dis-
charge valve stem. Schlndler
•303. Delbert •OSO

— -.\mmonia compressors. Operating,
by aid of thermometers. Fried-
mann 939

— .\mmonla condenser. Locating leaky

coil in. Sheridan ^75

— -Vmmonia discharge temperature 452, 898
— .\mmonia joint. Opening. Kell 381,

Fagnan •eSO

— Ammonia. Loss of. C. A. O. 70

— Brine. Calcium-chloride. Home-
made outfit to make. Keil "898
— Brine mixtures. H. J. M. 33%
— Brine pipes. Porous. Burley 681
— Cold-storage duty. Matthews 73
— Compression plant. Increasing ca-
pacity of. Blackstone 458
■ — Cooling air of buildings bv mechan-
ical refrigeration. Tweedy ^820.

Onhiils
— Cooling hot liquor.

Handlev

• — Congress of refrigeration " Indus-
tries

— Discharge pressure. High. S. H. S.

— Engineer, Status of. Creen

— Flooded system. Bonn 226, Hollo-
way

— Frost. Case of. Blair

— Frost, "Live" and "dead." Kell

— Ice. Clear, without reboillng.
Bonn

July I to December 31. 1911

POWER

13

REFRIGERATION

— Ice machines, CliaDglng. C. I. M.
— Ice makiDg with compressed air
— Ice plant. Repairs to. Carr
— Ice. Preventing red core in. Brons-

tornf
— Ice-water supply system. Turner
— Ice-water system, Air in. Herter
— Inquiries — Ammonia piping, etc.
— Insulation losses. Matthews
— Xonprecipitation of calcium chloride

from brine by ammonia. Smith
— Pipe. Steel vs. iron. Ball
— Questions on refrigeration — Hot
and cold compressor discbarges,
etc. Gale 226. Answers
— Relative costs of continuously and
intermittently operated refrig-
erating plants. Herter
— Repin's chemical refrigerating pro-
cess
— Rescue, A timely. Fagnan
— Russians to adopt Am. R. R. re-
frigerating system
— Santa Fe precooling plant
— Sheffield Farms Cos. plant. Rog-
ers
— Suction pressure. Change of.

^yauchope
— Thermal and static heads and flow

of heat and liquids. Matthews
— Ton of refrigeration — Note
— Water Cooling. Matthews
Refuse. Street, Briquets from
Refuse, Town, Combustion of. Davles
Register, indicate, record
Regulator, Boiler-feed pump. Mayer
Regulator. Step-bearing pump. Ber-

trand
Regulators. Feed-water
Rellly friction clutch
Remels transformer
Remington kerosene engine
Repair job, Crude. Creen
Repairing engine casting. Chapman
Rescue. A timely. Fagnan
Returns from coils. Elevating. La

Badle
Rewinding d. c. generator. Fenk-

hauson
Rhode Island coal
Rhode Is., License agitation. Mc-

Inls
Richards. F. Air in steam hoists
Richards, R. O. Davies' experience
Richardson electric coal scale
Richardson mechanical lubricator
Richmond's municipal plant. Blnns
RIdgway's conveyer belt
Rlvcrton turbine accident 104, 224,

372, 414,
Rivet length : chamfered holes
Riveted ,Iointg. Nickel-steel, Tests
Robb-Brady Scotch holler
Robb "McDonald" shaking grates
Robinson. Gas pres.-vol. chart
Robinson. Hoat equivalent of con-
densate from gas calorimeter
Rochester mud-drum explosion sequel
Rockwell. H. R. Questions for dis-
cussion 411, .">2S, GOl, 711, 74R.
828,
— Automatic engine stop
Rod. Piston. See "Piston."
Rogers. C. M. Sampling coal
Rogern. W. O. Iloosac tunnel electri-
fication
— Isnlnted power plant — Spctiritv

Mutual T.lfe bide BInghamton
— Sheffield Farms Companies' plant
— Tonev Island power niant
— Brooklyn sewage flushing plant
— Ayer mill power plant
— Tom Hunter, hoisting engineer
RogTie River Flee. Co. sale
Rolling holler tubes. Klrlin 2B,

Sterling
Roney Btokors. Test.s with
Roof leaked— Expensive economy
Rope brake. Smnllwood
Rope-drive limitations. Snow
Rope drive or electricity for textile

mills Booth .115). .lacknon
Rope drives. Efficiency of — Carnegie

Schools and fJermiin tests
Rope drivfs. Small
Ro«o. Steam engineer's experience

with gas power
Rotary conv»rters. See "Converters."
Rotor bar". Preventing, from loosen-
ing. Fuetterer 3r,n, Slegel '
Rotrex pump. C. If. Wheeler "
Robber pads under engine <
Running under. Air compressor ISO,

412. r.J2. (;7.'?, 7«fl, 8cn. m4, '

Rnpp. Heat transmission In boilers
„ ^ ••'"2,

Knshmore's opernting costn 170,

Russian englnenring exhibition, Baku
Russians to adopt Am. R. R. refrig-
erating system
Rusting See "Corrosion," etc.
Ryan. Maintenance of elec. circuits

•606

513

152

58

•167
646

•484

754
•388
'212
'480

369
'640

759

6T8

374
475
•913
•613
•268
•162
•389
•227
600
189
t686

'61 S

■soo

'442
'657

51
864

•510

•31 1

605
280

•838
•734

•755

•556
377
•781

"S-C" gage cock

SachsiscLe Maschinen Fabrlk's turbine

Safety. See also "Valve," "Stop,"
"Guard."

Safety appliances 899

Sage. Removing emulsified oil from

water 397, 426

St. Marys low-grade oil attachment 'ITS

St. Marys, Low-pres. turbine at

Salesman and engineer. Phillips 516,
Wing

Salmon. Saving with pumping engine

Salt Lake & Ogden wheel explosion

Salt test. Nitrate of silver

Samples, Gas, Apparatus for passing
to calorimeter. Berry

Sampling furnace gas. Eraser, Hoff-
mann

San Francisco central station

San Francisco, O. & S. J. Ry. Corliss
engine

Sand for hot boxes 340, Howarth 600,
Cordner 644, Freer 710, Benefiel
V4S, Sprague, Forgard. Bucklen
S69, Wallace 935, Blake, Hurd,
Kyger

Santa Fe precooling plant

Sargent combined gas engine and air
compressor

Saving of 40 per cent.

Saw, Slate, Improvised. O'Brien

Sawdon. Pulley-transmitting capaci-
ties

Scaite siphon water purifier

Scale caused low vacuum. Turner

Scale. Coal, Richardson electric

Scale in suction pipe. Hartley

Scaler, Boiler, Dallett pneumatic

School buildings. Heating and venti-
lating

School heating. Evans

Scotch yoke for engines. Beets

Schuchardt. Power-limiting react-
ances

Schiitte & Koertlng relief valve

Scranton. Fatal piping accident

Screen basin, Redondo plant ^200

Screw. Eltective pressure of 752,
Wagner

Screw pump. The. Johnson. Mason

"Sea " Rings piston-rod packing

Seager. Developments, Brit, steam
plants

Security Mutual Life bidg., BIngham-
ton

Seillger's Diesel engine Investigations

Setscrew came loose. Dickson

Sewage flushing plant, Brooklyn. Rog-

Shafting caluculations. C. E. S.
Shafting layout. Poorly designed
Shafting. Unalined. Waste of power

in. Kieffer ."i.'iS. Holly
Sharwood's automatic Injector valve
Sheffield Farms Cos.' plant. Rogers
Sheridan. Locating leaking coil in

ammonia condenser
Ships, "Olympic" and "Titanic"
Shock absorber. Prew •440, Noble
Shoes. Isolated power for making.

Wilkinson
"Shop Management." Taylor
Short flexible stuffing box
Show vs. efficiency 490, Dixon 710,

,Tackson
Shuman's sun-power svstem •SOe,

Shunt field. Position of
Shutdown, Avoiding. Candlish
Sickles. Steam-driven air-compressor

economies
Side plav In crank pin brasses, Mc-

Gahev •204. Bennett
Sight glass. Wire In. Sobolewskl

*.'>9S, .Johnson
SiKnals. etc.. Tank 'OS. •4S3. 559.

Silent running engines 224. Lane
Siphon, Homemade. Dnnner
Siphon water softener and purifier
Slat"" saw. Improvised. O'Brien
Smallwood. Determining value of

B. T. IT.
— Draft and dlfTerentlal gages
Smelter power plants. Reduction of

lubricating costs in. .Tohnson
Smith. M. B. Nonpreclpltatlon of

calcium chloride from brine by

ammonia
Smoke abatement Brit. standard.

Owens

173
260
291
•657
300
531

Smoke ati.ntement exhibition. London
.ron f'tnok" nbntement. C,t. Rrlt. : Man-
'•'-0 Chester conference. Kershaw

'8.'>0 Smoke. Anfl , law. Boston. Baker
'200 Smoke connections ; poor draft. •21

218, 220

Smoke consumers. British

•246

Smoke detector. Mirror. Bartlett

867

Smoke Indicator, B. R. I.

•3.-.

Smoke Inspprtlon

714

Smoke Inspector, Chicago, New

230,

•463, •602

Smoke preventer. Waldron

•21.1

Smoke prevention, fhlcago Bird

11.-.

Smoke prevention convention, loter-

nntlonnl

•80, 17.-1

Smoke prevention, large power sta-
tions. Vassar
Snap rings. Measurements of
Snow gas-engine test
Snow. Rope-drive limitations

So easy to fool 'em"
Solar motors. Blake T>OG, Ed.
Solder, Paste, Johns-Manville "Solder-
all" J9J
Soot blowers. "Diamond." •SO, •347, 'SIO
Soot cleaners. Vulcan, for economizers '

and Manning boilers •SSS

Soot. Effect on boiler performance 51

Southern Calif. Edison svstem. Mauler •35"
Southern Pacific's Parker boiler •544, 568
Speed vs. economy of engine. Clarke •2'J7
Speed. Intermittent. Economv of "go

Speed limit, Engine, Rockwell's •964

Speed of machinerv at night 530

Speed regulation, Bad : cutting out
dynamos in parallel. McKelway
„ „214. Appleton 2S8

Speller. Locomotive tubes ; treat-
ment • QJ^
Sprague. Voltage troubles in small

alternators (50

Spring drive. Tanis •70G

Spring. Safetv-valve. formulas 4lfi

Squirrel-cage bars, remedies for loose-

enlng of. Fuetterer 366, Siegel •520

Stack. See also "Chimney."

Stack arrangement. Peculiar. Thomas 'ISl

Stack. Brick. Throwing, in Cieve-

582, 868 land. Williams. •4,^3

•119 Stack. Cruse elector form •39.-

294 Stack. Steel. Erecting. Fischer 480

•613 Stack. Steel, Raising. Warren •ISl

•333 Stack. Steel. Repairing. Newcomb ^370

•347 Stacks— Chimnevs 439

Standard Oil Co.'s De La Vergne
•342 engine test. Towl •S94

•715 Standpipe freezing. Prevent. Nlchol-
442 son 411. Sullivan r,r,S. Herter

601. Zetterlund 7S.";, Noble, Leese
59 ^828, Speace S70

•122 Standpipe, Pressure In 338

862 Starting gas engine with steam.
, 224 Beach 140

Static boiler-feed regulator 'S'tO

•971 Statics. Problem in ^693

•27 Stationar-. Firm's, T'sing. Montague
•499 fi.'iO. rt7 83t

Staybolts, Diameter of 566

•245 Staybolts. Hollow. H. S. B. 260

Steam. See also "Engine." "Boiler."
•84 "Turbine." "Condenser," "Pump."

•249 "Trap." "Superheat," "Heating,"

786 "Gage." etc.

Steam and water temperature 647, 872

Steam charts. Excellent. Thomas •067

Steam consumption guarantees .<!24

Steam cost to contractor. Loomer 484

Steam discharged from jiipe to vessel 712

Steam drum to prevent wet steam.

Gilbert •2.14. Price 4S7. Sterling .'i27
Steam. Economy of using expansively 60.",
Steam ejector. Prew " •uOe

Steam engineer's experience with gas

power. Rose 328

Steam, Exhaust. Oil in 787

Steam. Expanding. Chart for mean

pressure of. Guv ^204

Steam flow meter, G. E. ^154

Steam generator and superheater,

Mullon and Wlchrawskl's ^77

Steam In cold boiler. Roundy 256.

Fitts 413

Steam .iet.s, Anti smoke, Boston .-,0

Steam. Latent bent in. A. J. S. 260

Steam plant design 188

Steam plants, British, Developments.

Seager ^245

Steam power plant design. Fischer •171.

•275, 472

Steam pressure and temperature 789

Steam. Saturated and superheated.

Comparative economv. Jones 10

Steam, starting gas engine with.

Beach X42

Steam. Superheated, tests. Hitch-
cock • 888
Steam supply to producer. Regulator

of, on yacht "Progress" ^141

Steam to gas producer. Varying. All-

eut 'OO, 100, 142

Steam velocity from bent energv 278

Steel vs. Iron pipe In refrigerating

work. Ball geo

Steel works. Large gas engines In —
A. S. M. E. Gas Power Section
discussion •IT, 29, 142, 178

Step bearing. See "Bearing.**
Stickle thermic valve •121

Stills for water 'eS, ^147, ^904

Slllz fuel oil burner •389

Stirling boiler circulating svstem '430

Stirling hollers. Detroit Edison's ^840, 863
Stock. Taking 72

Stoker. Detroit aniomatlc. Improved •l.'>7
Stoking. I'n.lerfeed. vs. overburnlng.

Woolson 801

Stokers — Air spaces. McGahev 67,

Brown ISS

Stokers. .Mech.nnlral— Boiler rating

722, 000

•801
712
•965

866
•500
•533

935
531
338

412
'861
'119
'781

14

POWER

July 1 to December 31, 1911

stokers. Mechanical, Qualification.

Vassar
Stokers, Koney and Taylor, on Stirling

boilers. Detroit
Stoltz. Mine power plant •G88,

Stop, Automatic engine, Kockwell's
Stop, Engine safety. Waldron
Stop valve. Improved. Seklgucnl

•.')2.3. ratterson
Stops. Enclne, Simple. Noble
Stop.s. Safety 110, Stewart C02, Dick-
Storage battery. See "Battery."
Story building, Los Angeles
Strain measurements of boilers
Strainers, Double, for pipes
Strode condenser packing tool
Stroke recorder, I'otter's "Adulsto-

meter"
Stuffing-box gland. Enlarged hole In.

Williams
Stuffing-box gland,- Repairing. Ber-

trand
Stufflng-box gland. Spilt. Parfett
Stuffing box, Packing. Ibach
Stuffing box, "Short" flexible
Stuffing box, Tall-rod. McGahey '"OS,

Bennett
Stuffing boxes, German turbines *468.
Stumpf unidirectional flow engine •685,

(Efficiency discussed) liellmann

•G.W. •9.^2, Stanwood 037,

Stumpf
Sturtevant gas-blower set
Substation. Flooded, Drying out.

Blake
Substation. Bemodeled, at Reading
Suction lift of pumps. Treeby
Suction pipes for pumps
Suction pressure, Change of. Wau-

chope
Suction producer. See "Gas."
Sulphur, etc., for hot bearings. Mc-
Gahey, HoUv 27. Mitchell 28,

Beard 100, Sterling 220, Blan-

chard 332. McLeod 409, Blessing

441. Baum 025, Gould
Sulphur in oil or gas. Olatsen 743,

.Jackson
Sulzer governor. Oil-operated
— Diesel waste-heat economizer
— Uniflow engine data
Sump switch and bell
Sun's rays, Power from. Blake '506,

Ed.
Superheat — Efffct on Iron
Superheated steam. Advantages of.

Maclntire
Superheated and saturated steam.

Comparative economy. Jones
Superheated steam, Elow of. a. H.
Superheated steam tests. Hitchcock
Superheater, Milne
Superheater, Steam generator and,

Mullon and Wichrawski's
Superheater, "Toltz." Power Equip.

Co.'s
Superheating and superheater — Ger-
man tvpes. diagrams, formula,

etc. Taylor
Sunerheating. Primary and secondary.

(Tellmann. *fi59, 952, Stanwood

937, Stumpf
Superintendent knew. The. Roth
Surface combustion In boiler •767.

Swab. Piston-rod. Langbeln
Sweetser. Offioe-buIIding power cost
Swingle. Pumps and calculations
Switch. Double-pole double-throw,

Substitutes for. Farblng
Switchboard. Easily built. McKel-

way, Harvey *177, Crane
Switchboard suggestion — Housing

sprockets, ijixon
Synchronous motors. Correcting low

power factor with

Tall-rod stuffing box. McGahey •705.

Bennett
T."ike no chances
Tank Indicator. Oil-storage
Tank cars. Union for. Dunn
Tank. Concrete compound, KolTel
Tank cone seam strength. P. L.
Tank. Contents of
Tank float. Key. Kell
Tank gage. Warner
Tank. Oil. telltale
Tank. Receiving, of heating system
Tank signals. Woolnian •98. Main
Tank. Size of. required. Fitzgerald
Tank valve and float, Faultily de-
signed. Little
Tank. Water, controller. Goodlett
Tanks. Oil Filling, etc.

PAGE

173

•840
•76J
•9'U

>154

•S6'i

•903

•708

•865

80

•364
•234

•637
078

896
260
250
953

151
•888
•346

•950
90.'}

787
•442

519
•96

•934
187
•839
•745
•671
•.370
972
5. '59
•598
•603
•116
•4S3

•094

722, 900
•841

•658
•9Gt
128
401
•436

fAQB
Tapping direct branch pipes •255

Tar fuel. Diesel engines '=>>"

Taylor, F. \V. "Shop Management' U^i-^

Taylor. .1. VV. Indicator-pencil vlbra-

tions •655. •076. •829, 8.0

Taylor, L. B. Causes and preven- ^^

tlon of corrosion
— Superheating and superheater
'Jaylor stokers — Boiler rating
'iavlor stokers. Tests with
Teclmology. Congress of — Papers
'Iclltale. Pump. Wilhelm
Temperature-conversion chart. Allison
remperature-expausion a 1 a g r a m.

Treeby
Temperature pendants. Greens
Tcrman. llydrauUc-hammer boiler test
— Why .Timmy was refused license
-Case of overpressure
Terminal pressure and compression il4

Terry turbine-pump generator 'oio

'XVsla's new prime mover '406

Tests. Engine tightness. Thomas

595. Brown 2-'0

Testimonial letters. Carruthers •utiO

Testing materials, International Asso. blu
Textile mills. Elec. drive for. Booth

519. (Kope drive) Jackson i02

Thermal and static heads and flow of

heat and liquids. Matthews •eoe

Thermal column. Wilkinson 247

Thermic valve. Stickle *121

Thermodynamics and Heat Engineer-
ing Problems. Miller, Berry,

1'1'ey „ . . „ ^. '**'^'

"Thermodynamics, Practical. Car-

dullo .„. '9'*

Thermometer-conversion chart- Alli-
son *1'*1

Thermometers, Centigrade and Fah-
renheit 64 r

Thermometers, Operating ammonia
compressors by aid of. Fried-
mann ^^-^

'I'hompson, Edgar, steel wks., gas en-
gines •17, 142, 178

Three- and two-wire plans, Operating

alternately on. Kaiser '"^

Three-phase circuit, Power in 338

Three-phase circuits. Power and cur-
rent in. Poole ^775

Timber carrying, Problem in **?'''5

liming the ignition. Pagett •SyO

"Titanic" and "Olympic" ^44

Tod. Wm., Co. — Large work

Toledo Ry. & Lt. Co.'s crane

Toltz superheater

Tomlinson. Steam-engine lubrication

•308

•303

390,

426, 711

Torpedo smoke consumer ,^246
Torsion dynamometer. Amsler *^Ql
Tower on combustion. Woolson 901
Towl. Oil-engine test •8'J4
Town-refuse -.'ombustion. Davies *167
"Trade" or "profession" * 930
Trade, Teach the boy a 72. Wise 4SG
Trausformer connections, 2-phase, 3-
phase. Grove. S. H. Harvey
•16. Malcolm. A. L. Harvey ^214
Transformer. Remek ^212
I'ransmlssion-Iine calculator. Adams' ^155
Trap bucket. Substitute. McEnaney 745
Trap connections. Elevating returns *495
'I'rap, Mercury-column. Mowat •750
Treeby. Temperature-expansion dia-
gram 'osa
Trenton Engine Co.'s Reeves valve ^231
Trlnks. High-speed cast-iron fly-
wheel *S99
Tube. See also "Boiler."

Tube, Boiler, accidents 686, 798, 'aSS

Tube-cleaning kink. Bailey ^23

Tube failure. Redondo, Calif. ^907

Tube spreader tool. Heely ^387

Tube-soot blowers, etc. •SO. •347, •388, ^810
Tubes. Bent, put in condenser. Fe-

naun •483. Owitz 784
Tubes. Boiler, Recent developments
in testing ; sulphur absorption,

etc. Speller *91
Tubes. Boiler, Rolling. Klrlln 26.

Sterling 184
Tubes. Leaking, Trouble with. Rel-
mers 104. Beaton 375, Wright
414. Cultra 488, Beneflel .527,
Chapman 598, Fenwick •786, No-

ble

971
294
813

•2
•356

412.
488, 751,

Tanks. Taper, Capacity. A. O.

Tanks. Water. Leaky. Pagett

Tantalum-filament lamps

Taper fits

Tappets, Noisy valve-gear. Johnson

•902

•444.
935
222
256

•701
454

•966

Tubes, Water, Bagged. Werner
Tungsten-filament lamps •701,

Tunnel. Hoosac. electrification. Rog-
ers
Tupper. Increasing efficiency of ro-
tary pumps
— Failure of mixed-pressure turbine

installation 497, 642

— Arine-power system features •735

— Changing alt. to direct current •852

TURBINE, INTERNAL-COMBUSTION

• — Gas-turbine problem. Attempted so-
lution. Blalsdell •367, Malcolm,
Knapp

TURBINE, STEAM

— Allis-Chalmers patent — Note 887

— Auxiliaries. Turbine-driven. London 610
— Bleeder turbine, Westlnghouse au-

tomatlc '193

— Brown-Boverie turbine. New o-W

— Circulating-water control. Auto-

matic ■"■■'-

— Combined steam turbine and Int.-

comb. engine, Thornycroft 809

— Costs. Relative, of turbine and en-

gine plants al5

— Curtis turbine. N. Y. Edison — Larg-

est In world •iiO

— Curtis turbines, Ayer mill ; valves
in special casing to take steam
for heating water •Si 6

— Curtis turbines. Portland, Ore. •942

— Curtis turbines. Redondo Beach

•198, 224
— Curtis turbo-generators, Wltherbee-

Sherman mine power plant 'OSS, '764
— European turbine practice — Com-
bined type : Zoelly turbine : tests
of European and American tur-
bines. Christie •625
— Exhaust outlet. Design of. Guy ^257
— Explosion. 111. Trac. Co.'s turbine
at Riverton 194. 224. '227, Jones
372. Blue 414, Stannon 600
— Foundations. Turbine. Smith 669
— Future work. Steam turbine for :
Westlnghouse practice, etc.
Dreyfus 536
— Gas blowers. Turbine driven. Sturte-
vant, in Brooklyn and N. Y. ^277
— Gear. Westlnghouse marine reduc-
tion *"92
— Generators — Baker ventilating

vanes 'ISe

— Germany. Steam turbine in. Junge
— Brown-Boveri types ^52, Maf-
fel-Schwartzkopff Wks.' Melms &
Pfenninger turbines, at Riga. etc.
•466. Siichsische M. F. turbine;
tests of shrouds on blade tips,
of blade pitch, etc. ^510 — Expe-
rience of Lasche (of A. E. G.) —
Steel, brass and bronze as blade
material, condenser tubes and con-
nections to avoid electrolysis ;
turbine foundations •550. Ex-
haust outlet, Bergmann turbine.
Guy *2o7

— Hackenberg turbine ^120

— Hoosac tunnel's Westlnghouse dou-
ble-flow turbine *6
— Japanese navy. Curtis turbines for •398
— Low-pres. turbine. Saving with.
Western Ohio Trac. Co., St.
Marys '317
— Marine turbine-engine installation.

Dickie *843

^-^Marine turbine. Growth of. Parsons *363
— Mixed-pressure turbine installation.

Failure of. Tupper 497. Battu 642

— Motor-turbine-pump outfit. Lachlne •384
— Natl. B. L. Asso. committee report 12

— Navy. U. S.. Turbines in 377

— Newcastle station — A. E. G. and
Brown-Boveri-Parsons turbines ;
record low steam consumption
turbine ^272

— Oiling trouble, Jones 409

— Olympic's low-pres. Parsons turbine '44
- — Pipe sizes. Turbine steam and ex-
haust. London 148. Treeby 415,
Neilson 444

— Power plant design — Turbine char-
acteristics. Fischer '273
— Pump. Auto, step-bearing. Lynn •IBS
— Racing prevention — Valve lubrica-
tion. Vinncdge '217
— Scale caused low vacuum. Turner 294
— Steam engines and turbines — Com-
parative tests. Westerfleld *279
— Terry turbine-pump-generator •576
— Turbine, generator and pump outfit.
Combination, West Boylston mill.
Williams '482
— Turbo alternators. 3-phase, Best
standard voltage and frequency
for. Crecellus 590
— Turbo - generators. Direct - current,
larger than 300 k. w. capacity —
Westlnghouse views. Dyer 591
—Unbalanced fields. Davis 637
— 'Velocity from heat energy 278
—Zoelly steam turbine 'SIS, Ed. 339

TURBINE. W.VTER

See aIso"Water." "Waterwhcel."
— "Hydraulic Turbines." Gelpke.

Van Clove
— McCormick turbines. Vernon, Vt.
— Prime mov<>r. New. Tesla's
Turin exposition power plant
Turner. Icc-w:iter supply s.vstem
Tweedy. Cooling air of buildings by

mechanical refrigeration •S2(),

Ophiils
Twlnlok blowofT valve
Two- and throe-wire plans. Operating

alternately on. Kaiser

July 1 to December 31, 1911

POWER

15

Uehling. Value of COj recorder 69. 258,
336. 445, 644, 871, 90o
— COj and boiler efficiency 847

tnion G. & K. station. Cincinnati *31o

— Draft-recording gage •232

I'nbalanced adds. Davis 637

Underfeed stoking. Woolson 901

Lnion for tanU cars. Dunn •74o

United States Bureau of Mines — Re-
cent worls, Flagg and Smitli 93.
Ed. 110. Gas-producer investiga-
tions 58. Electrical section 213,
Furoace-gas sampling and analy-
sis •282, Coal-purchasing specifica-
tions 584. Publications tS35, Elec-
tric shocis precautions 834, Peat

fuel 94, •gis

United States Steel Corp's. gas engine •17,
142. 178, 291, 895
Unloader gave trouble. Morton *931

Unloading coal cars. Williams 490

Utz. Disastrous use of water ^329

— Bad wreck from small cause •406

Vacuum and efflclenc.v. Heilman •660,

•952. Stanwood 937. Stumpf *9o0

Vacuum and gravity-return heating

system. Combined. Fuller ^190

Vacuum. Effect on turbine efficiency 530

Vacuum. Low. Scale caused. Turner 294
Vacuum. Value of. Weighton 72.

Morrison 202

Vacuum increased by reducing pump

speed. Brown 25

Vacuums. High 532

V.ALVE

— Alrdlscharge valves. Water-cooled '254

— Ammonia compressor, Protecting —

Safety valve between suction and

discharge ; telltale on discharge

valve stem. Srhlndler •.■?f)3. ^680

— Automatic cushioned .ingle and

globe valve. Golden-.\nderson '685

— Babcook & Wilcox valve gear 914
— Backpressure valve. Troublesome.

Little ^707

— Back-pressure valves 9«2

— BlowolT valve burst. Drcwry •780

— By-pass valve opening. Measuring •IS

— Blowoir valve. Twinlok ^812
— Check valve. Gelser automatic.

Long Grate Bar Co.'s '539

— Check valve In pas-supply line 928
— Check- valve repair. Emergency.

Nigh '484

— Check valves. Weighted and swing ^190
— Corliss engines. Bates — "Inertia"

valve gear and dashpot •498
— Corliss valve gear. Making It noise-
loss. McGahey •255, Mistele

446. Watson 644
— Corliss vahe stem. Locating ke.v-
wav In. KIrlln 'ISO. Johnson

414. Hawkins 528

— Cross romp, engine valve setting 4.52

— Crossheart. Broken. Cultra •931

— nisk. Composition. Ohio In]. Co.'s 797

— Exhaust valves. Gas-engine ^20

— Explosions. Stop-valve chest •5R3

— Gate valve. Banks •539

— Hamilton Corliss gravity valve gear •87.1

— Hopklnson Ferrantl gate valve •393
— Injector valve. Automatic, Shar-

wood's 'son

^Llnk motion, nomemadc. Little ^143
—Needle valv*. Homemade glass

float. De Sausnnre •825

— racking valve stem. Gokhe 670
— Pneumatic lift on valves. Sobolew-

«k! •867

— Port opening, fneqnal ^746

— Pump. Duplex. Setting valves 938
— Pump-valve crank, Makeabift.

Wagner '.'iSB

— Pump valve. Hill •79
— Pump valven. Rubber, Truing.

Farnswnrth 'T^l
— Rathhtin vntve gi-ar. Improved •gSS
— Redurlng valve In steam main. Mc-
Gahey 'ses
— Reeves nutn, adjustable piston

valve. Trenton Engine Co.'s •231
—Relief valve. Special design. Schtltte

A KoeHIng •122
— Ropair. Mnkrahirt, Pump valves.

Perras 103

— Repair, Temporarv, Warber •505
— Reversing valve for circulating-
water flow ; auxiliary air valve,

Cincinnati 'SIS

— Rotor. Valve. Coolev •fiSO
— Safety-valve area — Inqnirleo 151, 222, 452

— Pafetv-vBlve calrnlatlona. A. D. B. 49J

— RafetvvBlve nile 972

— Safety valv. Consolidated •462

lever. Graduating.

PAGB

VALVE

— Safety-valve

Morris

— Safety-valve spring formulas 410

— Setting, Single- and double-eccen-
tric Corliss. Ed. 300, F. B. C,
D. E. C. 301. Hawk 559

— Steam valves closed. Engine runs
with : leakage. Lantz 371. Dick-
son 488. Cannell 709, Benefiel
750, Mason 934

— Stop valve. Improved. Seklguchi

•523. Patterson 751

— Tail-rod stuffing box. McGahey

•705. Bennett ^934

— Tank valve and float. Faultily de-
signed. Little ^145
— Tappets. Noisy valve-gear. Johnson ^960
— Tests for tightness. Thomas 595,

Brown 830

— Thermic valve, "Stickle," Open

Coil Co.'s ^^21

— Turbine-valve lubrication. Vln-

nedge ^217

Van Brussel. London pumping station •652
Van Dorn & Dutton plant 957

Van Winkle. Ocean wave power •580

Vapor lock in fuel-oil feed pipe.

Leese 291

Vapor-pump troubles. Cllnehens 649

Vassar. CO2 recorders 69. 258. 336, 445,
644, 847, 871, 905
— Smoke prevention, large power sta-
tions 173
Velocity from heat energy 278
Ventilation. See also "Heating and

Ventilation."
^'cntilation of turbine generators —

Baker vanes ^130

Verdicts. Offhand 532

Vernon. Vt., hydroelectric plant ^124

Veteran. Another, Passing of •eiO

Vibracator. Hopewell *2G0

^ ibration. Reach rod. Nagle 68

Victoria falls plants 702, 741

Vilter Mfg. Co.'s Christie engine ^382. 528.
603, •eOO, 931
Vise clamps. Noble '371

Voltage troubles in small alternators.

Sprague 62

Vulcan soot cleaners •SSS

W

Wade. Crude fuel oil 730

Wages. Engineers' 368. 824, Massey
731. Phillips 766. Masoj, Orr 905,
(in China) Adams 885

Wages. Higher. Wright 443

Wakeraan. Heating factory addition ^648
^\a^ren. Confessions of engineer •SOS

Waste. Oily. Cleaner. Logic ^638

Water. See also "Heater," "Heat-
ing." "Turbine." "Waves."
"I'ump," "Cooling," "Refrigera-
tion." etc.
Water. Boiling, at 32 deg. 31
\Vater. Circulating, Auto, control.

Hughes •332

Water. Circulating, system, Redondo

•199. 224
Water-column connection. Dangerous.

Binns 292

Water. Condensing — Double service S64

V.atrr cooling. Matthews 152

Water. Condensing, calculations.

Fischer 473

Water-current motor. Price ^208

Water. Disastrous use of. Utz •32'J

Water distilling. Dickson. Noble,
I'nvls. Jonnson •08. Fagnnn •904.
(Drinking water) I'lTry. Notlberg ^147
Water ejector. lIomemad4>. Salmon ^292

Water. Engine Jacket. Heating shop

with. Hays •067

Water, Feed, purifier. Harmon 'So

Water. Feed, regulators 754

Water. Feed, treatment. Ferrochem

for •150

Water glass watrher. Position of 260

Water hammer. Boone 487. Harden

210. 528. McMahon 414. Leese .199

Water hammer causes. E. L. L. 832

Water hammer, heating system. Hud-
son •048
Wntcr bnmm«r In steam pipes 452
WatiT Immmer ruptures valvo chest ^583
Water liammcr — .shwk absorber •440,

Noble •675

Water h'-nd loss In pipes. Poch*" ^134

Water. I light and pressure of H. P. W. 189
Water In red-hot boiler, etc. — Rock-
well's questions 411. 528. 601. 711.
748. 784. 828, 935
Water. Hot. heating, by forced circu-
lation. Lackawanna H. R. termi-
nal, etc. Evans ^112, •4r,}
Water. Hot. heating for high build-
ing". Evans •92.">
Water. Hot. school heating. Evans ^715
Water. Hot. supply. Noble ^903
Water. Hot. svstem and liispecttOD

troubles. Evans •492

Water. Ice. supply system. Tamer ^74

Water In ashpits 929

PACE

710
938
339

•182
247

Water In boilers, Lifting. Harden
216. 52S. McMahon 414. 711,
Boone 487, Leese 599, Terman
Water in 1. p. cylinder
Water in power-plant piping
Water, Measuring specific heat of
Water measuring without meter — A

velocity meter. Anderson
Water of condensation, lieturuing —

Wilkinson thermal column
Water power, Colo, riv., Calif. 540, S33

Water-power conservation ; develop-
ments 408
Water-power dam. Keokuk. Kirlln •359
Water-power development. Los An-
geles aqueduct. Allison ^478
Water power. Land withdrawals for 917
Water-power license law. Ore. 576
Water-power notes 772, 779
Water-power, Pac. Gas & Elec. Co.'s

252, ^731
Water-power plant, Richmond ^162

Water-power plant. Schaffhausen 628

Water-power problem. Commercial.

Ennis ^732

Water powers, N. Y. State 930

Water powers. Southern Calif. Edi-
son's '352
Water-pressure recorder. Lea •S'S
Water. Removing emulsified oil from.

Sage 397, 4-26

Water resources of Minnesota 285

Water rights in Wash. — Palouse case 540
Water rights. State regulation, Calif. 568
Uater separator. Air-compressor ^306

Water. Soft, snd boiler scale 454

Water softener and purifier, Bartlett-

Graver
Water softener and purifier, Scalfe si-
phon
Water softening — Boiler corrosion
Water — Sump switch and bell
Water supply. Increased. Pittsburg
Water-tank controller. Goodlett
Water-tank float. Keg. Keil
Water-tank signals, etc. Woolman

•98. Main ^483. Warner
Water-tank valve and float
^^'ater tanks. Leaky. Pagett
Water treatment to prevent corrosion
Water vapor in air

— Resulting heat loss 109. 118, 372,
Water wrecked 1. p. cylinder. Low

009. Jones
Waterbury Mfg. Co. heating
Waterwheel. Current. Power of A. P.
Waterwheel gate. Remote control of.

Whitmarsh
Waterwheel plant design. Examples of

poor. Kimball

Waterwheels. Parallel operation of

alternators driven by. Dean's

discussed ; use of governors 136,

Waterworks. Cincinnati. Blake ^310.

High record, etc. 61."

Waterworks. London. Van Brussel
Watson, J. Potblyn. Pump Doctor 438.
•641. 642. 649. 650.
Watson. T. H. Installing elec. motors
Wauchope. Change of suction pressure
Waves. Ocean, Power from. Van

Winkle
Weber. Gas power In mfg. establish-
ment
Weir's rotary nlr pump
Welding a flange. Russell
Wentworth. I'ower transmission on

oil-power \'(ssels
West Berlin wheel explosion. Parker
159. 784. Ed. 187. 532. Chandler
•344. McKelway 529, FItts 674,
Chandler
V.'est Jersey A Seashore R. R. costs 61, 514
West. E. A. Portland generating sta. *942
Western Ohio Trac. Co.'s turbine
Wcsterfleld. Steam engines and tur-
bines
Wcstlnghouse — Equipment. Hoosac

tunnel
— I>-blanc air pump

Automatic bleeder turbine
— Turbine practice. Dreyfus
— Views on d. c. turbo generators
— Marine reduction gear

Wet strnm. I'reventlng •254, 487, 527

Welherlll & Bros.' engine •771

Wheel. Flv — .Vvoldlng shutdown
Wheel. FIv. diameter ; rim velnrlty
Wheel. Fly. explosion. Baltimore
Wheel. Flv. explnslon. Farmlngton,

I'lah. Piper
Wheel, l-lv. explosion. West Berlin.
Mnsn- -Wocester Rv. Parker I3!t.
784. Ed. 187. 532. Chandler ^344.
McKelwnv 520, Fltts 074, Chand-
ler
Wheel. Flv. Highspeed cast-iron.

•33

•ll9
67

•86
349
•902
559

•.598
•145
256
520
899
•430

871
860
151

•781

•965

050

451

750

•317
•279

193
530
5B1
972

672
452
•682

•737

r'amhria Steel Co.'s. Trinks

Wheel. Fly. Large engine. Erecting.
Holly

Wheel. Fly. wreck, Hagerty shoe fac-
tory

Wheels. Fly. and centrifugal force.
Odell

Wheeler. C. H.. "Rotrex" pump

White Star liners, largest

750
390
884

•476

•850

•44

16

POWER

July I to December 31, 191 1

Whitehall bkl?. oiling system

W hltewash. Boiler-room. C. K. N.

Whltlnc Coal handling, Muncle

Wlfkes boiler eirculatlng system

Wild's calorlmet<>r

Wilkinson thermal column

Wilkinson. W. IS., Isolated power for

making shoes
Wlllard. Size and care of belts 'll.
221,
Williams. Throwing brick stack
— Unloading coal cars
Williamson Trade School. Pratt
Wllllston. Selecting right motor 520,
Wilson & Furneanx smoke consumer
Wiredrawn steam. .T. O. C.
Wiring. Eloc. Practical points. Edge

•4n7. '741. Uopeter ♦.'555. Garlltz
Wltherbee-Sherman power plant 'OSS,

•430
•.■?8i)
247

496
434

\\olf locomobile 'Sg-^. (Efflclcncy)
Ileilmann •659, •952, StaDwood
937. Stumpf •952

Wood. Meat loss due to moisture in.

E. II. 370

Wood. K. F. West Jersey & Seashore

H. R. costs 61, 514

Wooden knockoff plate •403

Woodworking shop, Producer-gas

power plant in 923

Woolman. Points In operation of suc-
tion-producer plants 329

Woolson. Inderfeed stoking 901

— First Western built automatic en-
gine 914

Worcester Kv. flywheel explosion 159, 187,
•344. 529, 532. 674. 750, 784

Worthlngton pumping engine. Provi-
dence 'SSS

Wreck. Bad. from small cause. Utz
Wrecked. How engine wa.s, Hurdlck
Wrench. Combination. Atwood
Writing for technical paper. Wester-
field 66, Wallace 107, Smart
Wroughl-Iron castings
Wyoming, Oil in

Yacht "Progress," Gas-power
Yoke, Scotch, for engines. Beets

Zocllv steam turbine 'SIS, His views
(Ed.) 339 Christie

NEW YORK, JULY 4, 1911

No. 1

H

FvRE is foolish question No. 6,678,459: When
is a man beaten?

Only when he thinks and admits that he is.

Mostly, success is built on failure. By this we mean
that often success is attained only by the aid of experi-
ence gained through unsuccessful efforts. Point out
the man who has never met with failure and we will
point out a man who has never accomplished anything
worth while.

Perhaps the saddest thing in all the world is to hear
a grown man in the full possession of his faculties
whimper that he "can't" do this or accomplish that.
A man who is in such a mental panic that he refuses
to make an effort to accomplish what he desires is
almost without hope.

Some dogs are gun-shy. In certain cases this terror
of firearms is inborn: in others it is due to a fright or
perhaps an injury the dog has received during puppy-
hood.

Whatever the
cause, the dog can
never be broken of
his gun-shyness.

There is a similar-
ity between gun-shy
dogs and opportun-
ity-shy men — men
who will not tackle
an opportunity
through fear of not
being able to make
good. S')me men
are born with a
"yellow streak" in
their makeup.
Others, after meet-

ing with two or three reverses, become a bit fright-
ened and lose their nerve.

Here the similarity stops, however, for while the
dog cannot be cured of his fright, the man can. The
dog's power to reason is exceedingly limited: it is his
instincts which inlluence his actions to the largest
extent. In man the opposite is true: reason exerts the
greatest influence and instinct plays but an extremely
minor part. Hence, by self- education or otherwise,
man maj' ovetcome his timidity.

Rightly constituted to begm with, or else rightly
educated and trained if he has quitter instincts, a
man who meets with a rebuff is only spurred to re-
doubled effort. Equipped with the experience gained
during his former failure, the likelihood of his meeting
with success is just so much greater. Thus it has been
truly said that success often comes from the wisdom
acquired during a multiplicity of failures and defeat
is often but the forenmner of success.

When an honorable effort results in defeat it is a
misfortune only when it gives rise to fear and prevents
therebv further ventures.

When a failure
acts as an incentive
to increased effort it
is often a blessing in
disguise, bringing
ability to attain
greater success than
otherwise could be
hoped for.

Let's not worr\',
then, about the mis-
takes we have made :
tomorrow will bring
as good a chance as
ever you let slip or
slipped up on And
it's yntirs to tackle.

POWER

July 4, 1911

Electrification of Hoosac Tunnel

In 1840 plans were made for tunneling
the Hoosac mountain, but after several
experimental failures the task was aban-
doned for ten years. In 1851 the work
was again resumed. From the summit
of the mountain a shaft 15x27 feet in
dimensions was sunk to a depth of 1028
feet, and a similar shaft was made upon
the western slope of the mountain. With
these shafts work went on at several
different places as well as at both ends
of the tunnel and engaged diiTerent forces
of men. This preliminary work occupied
four years of continuous labor and ne-
cessitated the exoenditure of half a mil-
lion dollars.

Twenty-five years after the work had
been begun the bore was completed. On
February 9, 1875, the first train of cars
passed through the tunnel, although it
was still far from completion. To pre-
vent disaster from falling rocks the tun-
nel was securely arched, 20,000.000
bricks being required for this work. Fig.

By Warren O. Rogers

For 35 years all trains were
drauii through the Hoosac
tunnel by coal-hurning loco-
motives, but for the last few
years oil-burning locomo-
tives have been xised for
freight. The oil btcrners
will soon be dispensed with
and electric locomotives will
draw both passenger and
frciglit trains through the
tunnel. An uptodate tur-
bine plant will supply the
electrical energy.

1 shows a view of the west portal as it
is today.

In the autumn of 1876 the tunnel
was pronounced safe for travel and regu-
lar trains began to pass through it. This
tunnel, which is 7;4 miles long, 26 feet
wide and 26 feet high, is double tracked.
In the beginning it was estimated that
the total cost of construction would not
exceed $2,000,000, but the actual cost
was 520,241,842.31 and 195 lives were
lost during the progress of the work.

The profile of the tunnel is made up
of about 2.25 miles of 0.5 per cent, up-
grade, a quarter of a mile of level track
and about 2.25 miles of 0.57 per cent,
downgrade. The west approach has an
upgrade of 0.8 per cent, and the east
approach an upgrade of 0.5 per cent.
The steam locomotives will be hauled
through the tunnel with the trains, but
will do no work.

The passenger-train schedule is nine
minutes, and the freight-train schedule

Fig. 1. View of the West Portal of the Hoosac Tunnel

July 4, 1911

POWER

is 16 minutes in running- through th£
tunnel.

For 12 months ending March 31, 1911,
522,526 freight cars and 35,600 passenger

or>e thousand 2 .-inch holes, 18 inches
deep, drilled into the roof for hangers,
and fifteen hundred lJ4-inch holes, 6
inches deep, for telephone- and signal-

rent. Two of them are shown in Fig. 5.
The current at 11,000 volts, 25 cycles, is
collected from an overhead wire and
passes through a transformer in the loco-
motive. From this transformer various
taps are led out so that any required
voltage may be delivered to the motors.
Each locomotive is equipped with four
320-horsepower, 300-volt, single-phase
motors which are bolted directly to the

iVf^"tv:

-BURNING Locomotives for Freight Service

cars were moved through the tunnel by
44,542 engines. If these freight cars
were coupled together they would ex-
tend from Portland. Me., to Los Angeles,
Cal., and the passenger cars and engines
would reach from Boston to Chicago, 111.
If the engines and the passenger and
freight cars were coupled together it
would take 17 days 2 hours for the train
to pass through the tunnel at the rate of
12 miles an hour.

At the present writing, all freight
trains are drawn through the tunnel by
oil-burning locomotives, one of which Is
shown In Fig. 2. It is of the Mallet
articulated type and is compounded on
both sides. This method of handling the
trains gets rid of considerable smoke,
but the average time (13 minutes) it
takes a train to pass through is a de-
cided objection to this arrangement.

A fan located at the central shaft
draws the smoke out of the tunnel and
when reversed forces the fresh air Into
the tunnel. Although this fan helps to
free the tunnel from the obnoxious gases
to some extent, they are at times most
annoying to passengers and greatly de-
lay the passage of trains.

To facilitate the handling of trains etr-
tcrlng the tunnel, the Boston & Maine
Railway Company has electrified the tun-
nel and line from North Adams, Mass.,
10 a point several hundred feet beyond
the east portal, a total distance of about
seven miles. Fig. 3 shows the overhead-
line constniction In the North Adams
yard, and Fig. 4 the method employed
in securing the wires to the roof of
the funnel. The tunnel work required

cable supports along the side walls. The
holes are drilled and the hangers are lo-
cated everj^ 100 feet. Four roof holes
and from 2 to 16 side-wall holes are also
placed at the 100-foot point.

Electric Locomotives

The five locomotives, built by the West-
inghouse Electric and Manufacturing

Fig. 4. Showing Line Construction in
THE Tunnel

frames. They are connected to the driv-
ing wheels by flexible gears and a spring
drive and operated by the multiple-unit
electro-pneumatic control, making it pos-
sible to operate one or any number of
locomotives together from one master
controller; or, any motor can be cut out
by opening its individual switch.

Three of these locomotives are intended
for freight service and are geared for
a maximum speed of 30 miles per hour.
Tliese locomotives arc designed to«haul
a train of 2000 tons through the tunnel

Fig. 3. Ovi

CfJNSTRUCTIoN IN I UK NoKTII AHAMS YARD

Company and the Baldwin Locomotive without difficulty. Tlic other two loco-
Works, for this work represent the latest motives arc for passenger service and
and most powerful type of electric loco- have a maximum speed of .SO miles per
motive for use ii'ith alternating cur- hour.

POWER

July 4, 1911

Although they weigh approximately drawn through it to the stack by the

250,000 pounds each, these locomotives, 12- foot fan, manufactured by the Massa-

owing to their comparatively high center chusetts Fan Company. In case the

of gravity, their mode of suspension and economizer is cut out of service the gases

Fig. 5. Two of ths Five Electric Locomotives

articulated trucks, ride very smoothly
and do not exert excessive strains on
the track.

The power plant that will generate the
electrical energy for these electric loco-
motives is located at Zylonite, Mass.,
and the transmission lines run to switch-
ing stations located at both ends of the
tunnel. The plan of the power house is
100x200 feet. The basement floor is on
a level with the ground; the generating
and boiler rooms are one story above, and
a switch room is located at one end of
the building.

DoiLER Room

The boiler room (a partial view of
which is shown in Fig. 6) is designed for
ten 500-horsepower Bigelow water-tube
boilers, four of which are in place at
present, equipped with Taylor under-
feed stokers. The stokers are driven
by means of a chain belt and sprocket
from a shaft hung from the basement
ceiling. This shaft is driven by a belt
from the shaft of a turbine-driven blower
set.

A balanced-draft system is used for
supplying air to the furnaces. In the
basement are the two forced-draft fans;
each is driven by a 150-horsepower di-
rect-coupled Terry steam turbine, and de-
livers air to a sheet-steel air duct which
runs under the boilers in the basement.
From the top of this air duct there are
four branch outlets. Each is made with
a Y-shaped opening, each branch sup-
plying air to a separate ashpit. The
opposite outlets are blanked, having been
arranged to take care of additional boil-
ers when installed. Each boiler is
equipped with a Foster superheater which
superheats the steam 75 degrees.

In a room above the boilers and at
one end of the building are two 12-foot
induced-draft fans (Fig. 7), each driven
by a Fleming fan engine.

The hot gases pass through a smoke
flue to the Sturtevant'economizer and are

are bypassed directly to the fan and the
12-foot stack. Provision has been made
for the installation of two more in-
duced-draft fans of the same size as
those now installed.

The forced-draft fan creates a draft
of 3 inches, the induced-draft fans from
3/10 to 5/10 inch.

Handling Coal and Ashes

Coal is delivered to the plant in hopper
cars and is dumped into a hopper from
the car and passes through the bottom
into the buckets of a Bergen Point Iron
Works bucket conveyer 75 feet long and
capable of handling 40 tons of coal per
hour. The conveyer travels in a runway
supported on trestle work; the runway is
. covered with a galvanized corrugated-iron
casing, as shown in Fig. 8.

The coal is discharged into a 75-ton
storage bin, but before reaching the stor-
age bin the coal passes through a set of
coal-crushing rolls. From this storage
bin the coal is delivered to the stokers
by a trolley-traveling coal car capable of
handling five tons per trip. The car is
fitted with a spout and the coal is de-
livered directly into the hopper of the
stokers. There are two of these cars,
the duplicate car being for service when
another row of boilers shall have been
installed. The tracks upon which the
cars run are carried by the iron frame-
work supporting the boilers and building .
proper. One of the conveying cars is
shown in Fig. 9. Each car is equipped
with scales for weighing the coal.

All ash from the furnace drops into
an ashpit hopper, the sides of which slant

Fig. (3. Paktlxl \'iii\\ oi- the Boiler Room

July 4, 1911

P 0 \<' E R

Fic.

F'

,N Fan Room .\hl'\e um Bl'illks

toward a common center. Suitable gates
are arranged at the bottom through which
the ash falls into an ash car which runs
on an industrial track to the outside of
the plant. This feature is shown in
Fig. 10.

Feed Water

Feed water will be obtained from ten
artesian wells, each 100 feet deep, six
of which are now in operation. The
wells are expected to deliver 10,000 gal-
lons of water per minute into a reser-
voir located under the turbines. It is
pumped by a 14 and 12 by 12-inch Piatt
Iron Works service pump through a Hop-
pes open feed-water heater and Willco.x
water weigher to an iron hctweil tank
located in the basement of the boiler
room. The water is pumped from the
hotwell to the boilers after passing
through a Sturtevant economizer by
either of two 12 and 7'j by 15-inch
Worthington pot-valve, outside-packed.

duplex, boiler-feed pumps. These pumps
are also connected to the circulating-
water intake from the cooling pond so
that pond water can be used for boiler
feeding should it become necessary. All

duplex pumps in the plant are equipped
with automatic governors.

Piping

There is hut one feed-water line and
one main steam line. All steam piping
drops down through the floor to the base-
ment where possible. The exhaust steam
from all of the auxiliaries passes to the
heater. Fig. 9 shows a partial view of
liL' piping over the boilers. A plan and
•in elevation view of the plant are shown
in Figs. II and 12 respectively.

Condensers and Cooling Pond

Each turbine exhausts into a Westing-
house Leblanc condenser, one of which
is shown in Fig. 13. The circulating
pump is driven by a Westinghouse steam
turbine at 1000 revolutions per minute.
Water is taken from a cooling pond at
one side of the power plant, and thence
from a concrete intake through a race-
way made of planking which runs to the
far end of the pond. This enables the pump
to draw from the coolest water. The water
from the condenser runs into a reservoir
and is pumped through 110 Schutte

Fic. 8. Exterior of the Plant, Shovx inc Coal CoNVtVER

& Koerting spray nozzles, 80 of which
are 2' j inches and 30 are 3 inches in
size. The piping supporting these nozzles
is 10 inches in diameter at the start and is
uradualiy reduced to <3 inches in diameter
It the extreme end. Fig. 14 shows one
of the '^pray pipes with the nozzles in op-

FiG. 9. V;t'A OF Tin. P;; :;.& .vlr the Boiler?

Fir. 10

NiiiR Ash Hoppiir

POWER

July 4, 1911

eration. The water is pumped from the densed water and is held as a reserve energy to the lines at a pressure of 11,-

condenser hotwell to the spray nozzles unit whereby the excess water can be 000 volts. These are single-phase, 25-

by means of a vertical 100-horsepower discharged direct to the cooling pond cycle generators and run. at a speed of

induction motor direct coupled to a 16-' through gates provided for that purpose. 1500 revolutions per minut*. The gen-

Sotter Room floor

6'Bypass
^■Branch Duct i'Steam J IZ'Steam

<Y- ?^'8oilerFeed

Engine Poom Floor

Fig. 12. Sectional Elevation of Basement, Showing Pu.mps and Piping

inch Worthington centrifugal pump. There Turbines erators are cooled by air taken in through
is also a 12-inch pump of the same make the side wall of the turbine-room base-
that is driven by a 9x1 0-inch Blake ver- '"^'''^ ^""^ ^' present two 3750- ^^^^ ^^^ passes to the generators
tical engine. This unit is not of suffi- kilowatt Westinghouse double-flow steam tnrough a galvanized air duct. Fig. 17
cient capacity to handle all of the con- turbines in place, delivering electrical shows a portion of the turbine room.

ssk<^^;m^-^^S?^\\m>j;j;^^

Fig. 11. Plan of the General Layout of the Machinery, Boilers and Piping

July 4, 1911

POWER

Owing to the incomplete condition of the
turbine room at this writing, a photo-
graph showing it in its entirety could not
be obtained.

There are two exciter units: one con-
sists of a 100-kilowatt, direct-current
generator and is driven by a 150-horse-
power three-phase induction motor. The

A motor-driven air compressor, cap-
able of displacing 50 cubic feet of air
per minute, at 183 revolutions per min-
ute, is driven by a 15-horsepower three-
phase induction motor. The air is used
for cleaning the generator, etc.

All motors are of the three-phase, 25-
cycle, 440-volt type and the electrical

basement and, after passing through the
filter, is pumped by means of the Worth-
ington 6 and 7'.. by 6-inch pumps to
the oil tank in the fan room, whence it
returns to the bearings by gravity

Electrical Trans.mission

The necessary apparatus for handling

the electric-energy ijcncrator it; located

Fig. 13. Leblanc Condenser Connectedto Double-flow Turbine

Fig. 15. E.ncitek Units and Air Co.m-
pressor

other set consists of a 100-kilowatt direct-
current generator direct coupled to a
Westinghouse turbine.

There is also a small motor-driven set
that is used for charging the storage bat-
tery, but it can also be used for a short

equipment throughout is of' the Westing-
house make. These auxiliary units are
shown in Fig. 15.

The bearings of the turbines are cooled
by water circulating around them, the
water being pumped by the service pump

at one end of the building in an alcove
off the end of the generator room. The
transformer for the station is built back
of the switchboard in the second story.

Fig. 11. One of the Spray Pipes in Operation

Fic. 16. View of the Switchboard

period to furnish exciter current for the
main generators, the motor being driven
from the storage batteries. This set con-
sists of a 12-horsepower three-phase in-
duction motor and a 7 '^-kilowatt dlrecf-
xiurrent generator, both mounted on the
same shaft.

Into a tank located in the induced-fan
room over the boiler; it is shown in
Fie. 7.

Here also Is the oil tank containing
the clean nil used In the turbine bear-
ings. After leaving the bearings the oil

Oil switches are also placed hack of the
switchboard, which is shown in Fig. I'>.
The transmission lines run from the sta-
tion on dead-end steel towers of the flcx-
iblc type to a switch house at the en-
trance of the west portal of the tower,

flows by gravity to an oil filter in the 2'' miles distant.

POWER

July 4, 1911

Burning Gas under Boilers
By G. a. Click

Gas as a fuel possesses certain ad-
vantages, some of which are as follows:

Gas can be regulated and burned under
a boiler in a very uniform manner.

It can be fired so that the boiler will
carry a heavy overload.

As fuel in a boiler room it means a con-
siderable saving in labor, as fewer fire-
men are required and there are no ashes
to be handled.

Gas has no detrimental effects upon
the boiler; at least, none have been shown
up to the present time.

High boiler efficiencies may be ob-
tained with gas if fired correctly.

Artificial gas is usually too expensive
to burn beneath a boiler, and for a long
time n?tural gas has had no competitor
in this class of work. Of late, however,
many of the steel companies of this coun-
try have erected byproduct coke ovens
near their mills in order to obtain coke
for the different metallurgical operations,
and in this process a large amount of
gas is given off as a byproduct. This
is rich in hydrogen, of which it contains
about 50 per cent., and also contains
about 25 per cent, of methane in addi-
tion to some carbon monoxide and
ethylene. The gas has a heating value of

of the burners, which are placed in the
doors of the furnace, one burner to each
door. These drop legs are flanged about
seven feet from the fioor so that the
burner can be removed quickly in case
the gas supply should fail, and it is de-
sired to fire the boilers with coal. The
whole operation of removing the gas
burners and building a coal fire can be
accomplished in 30 minutes.

As seen from the illustration, the
burner consists of three principal parts:
the inner pipe carrying the gas, the large
outer pipe carrying the air, and the slid-
ing sleeve over this air pipe for adjusting
the air supply. The burner is of cast
iron and is machined over the part upon
which the sleeve slides. The ashpit doors
are kept closed and all other openings
are sealed, so that practically all the air
si:pply enters through the burner. This
makes the control of the air supply very
easy, and uniform conditions are ob-
tained.

At first the grates were covered with
a course of brick with an opening 4
inches wide across the front of the com-
bustion chamber. Checkerwork of fire-
brick was also built up in front of the
bridgewall. It was found, however, after
changing to coal that the results were
just as good when the grates were sealed
with ashes and cinders, and the checker-

about 540 B.t.u. per cubic foot, and
about 20 cubic feet is equivalent to a
pound of Illinois coal.

This gas is being burned successfully
vnder a 400-horscpower Stirling boiler
with the standard combustion chamber,
and under a 300-horsepower Rust boiler
having the dutch-oven type of combus-
tion chamber. A burner of the type
shown in the illustration is used and is
similar to the well known Bunsen burner.
The main gas header runs along the front
of the boilers and has drop legs to each

cases being over 70 per cent. This lack
of any difference due to the flame is an
important point and seems to be due to
the fact that coke-oven gas, being com-
posed principally of hydrogen and quick-
burning hydrocarbons, is largely burned
before reaching the cool tubes where the
unburnt carbon might deposit. At first
after removing the checkerwork in the

nul'HL|--H-ll\\ Tl RHilNhS

work and other brick in the combustion
chamber were dispensed with.

The general operation of the boiler is
as follows: The gas is delivered to the
burner at a pressure of about 3 inches
of water and the amount of gas is regu-
lated by a plug cock. The air supply is
regulated at the burner and may be made
to burn the gas with a blue flame. It
was thought at first that this flame might
be more efficient than the yellow flame,
but actual tests showed practically no
difference, the boiler efficiency in both

Gas Burner

boiler it was feared that the tubes might
become blistered, but no more trouble has
been experienced with gas than with coal,
especially in the case of the Stirling
boiler. This boiler may be forced to 50
per cent, above its rating with no danger
of blistered tubes, while the Rust boiler,
owing to the vertical construction of the
tubes, is only carried to 15 or 20 per
cent, above its rating.

The Supply of Coal

The Black Diamond recently credited
the Government with the following in-
teresting information, as to the estimated
quantities of coal remaining in the
ground:

The Government has not considered
anything which runs below 3000 feet.
Upon that basis, taking the area know-n
to contain coal and figuring all of the
seams known to exist and figuring 1200
tons as recoverable under present meth-
ods from each foot thickness of coal
from one acre, the Government comes to
the conclusion that the recoverable
amount of coal is 9,000,000,000,000 tons,
which means that 9,000,000,000.000 tons
is 60 per cent, or thereabouts of the
coal actually in the coal measures and
that this amount could be increased if
our methods of recovery could be im-
proved.

In contrast, the Government put out a
statement of the amount of coal which
has been extracted from the ground so
far in the history of this country. The
statement is made that not to exceed U,-
000,000,000 have been taken out. If we
have 9,000,000,000,000 tons remaining
and if it has taken us 75 years to take
out 11,000,000,000, it would seem that
we have enough coal to last for a con-
siderable period.

However, the point is not mentioned
that most of this coal is at perhaps an
average of two thousand miles away from
the present centers of population. No
considerable part of this coal is given as
lying east of the JVtississippi river.

July 4, 1911

P O.W E R

Some Notes on Purchasing Power

The average power purchaser is ver>'
much at sea when examining the con-
tracts submitted by many of the power
companies, these contracts being so
worded as to be beyond the understanding
of the average man. and some of them
beyond the understanding even of the
technically trained man. This is largely
due to attempting to get a sliding scale
of prices for various conditions of power
service all into one form of contract. In
some contracts the prices vary widely, de-
pending upon the amount of power con-
sumed during the month; and in addition
to these, there are discounts which also
modify the final price, these discounts
applying in such a way as to make it al-
most impossible for the average con-
sumer to figure out what his power bills
actually are — he either having to hire an
expert for the express purpose of check-
ing his power bills, or to go on the as-
sumption that the bills as rendered are
correct and pay them without question.
This latter method is hardly to be com-
mended, as few of us would be willing
to pay our bills blindly, with the idea
that they are always correct; we prefer
to check them up and know what we are
paying for. In some cases even after
very strenuous effort to explain on the
part of the representatives of the power
company, we have found that the con-
sumer is absolutely at sea as to how the
bills are made out.

Contracts of this character should be
discouraged, and the consumer should
teke the ground that a contract should be
so plain and distinct as to be readily un-
derstood by anyone of reasonable in-
telligence who will carefully read it.

There are other contracts based upon
a maximum demand, a fixed charge per
horsepower of connected load, and a slid-
ing scale by means of which the power
bill may be calculated by one who under-
stands the language in which the con-
tract is written. This, however, is by no
means always the case, for kilowatts,
kilowatt-hours, amperes, ampere-hours
and horsepower are so frequently mixed
up as to make it difficult for the uniniti-
ated to translate what the contract actu-
ally refers to.

The maximum demand as frequently
expressed, is one which the average con-
sumer has hard work to understand, and
also the length of time over which the
maximum demand extends or upon which
time the maximum demand rate is
charged also is a matter of extreme dif-
ficulty. Some contracts allow the maxi-
mum demand to be that power which will
exist for a period of half an hour; others
fifteen minutes, and others take the ex-
treme position of two minutes. This lat-
ter figure in many cases might mean that
the purchaser is paying for a vastly

By Henry D. Jackson '^

Co)ifyac{s betueen the cen-
tral station and power users
are as a ride complicated
and misleading, and arc
usually all in favor oj the
central station. The con-
tract should be worded so as
to be equally understood by
both parties, and the con-
sumer should insist on
equal protection.

•I'lmsTillins ensinter, Doston, Mass.

greater amount of power than is justified,
owing to the starting conditions and
method of starting employed on the
premises. The limiting period or the
shortest space of time which should be
allowed in any contract upon which the
maximum demand is figured, should be
10 minutes, and preferably half an hour,
although under special conditions a
shorter time might be allowed if the con-
sumer is thoroughly well up on what the
term means. The maximum demand
should mean, and is meant to mean, the
maximum peak load which may occur,
which will last over the period stated un-
der the head of maximum demand. The
time limit should be sufficiently long so
that this will not include a temporary
short circuit, a temporary overload, or
the possibility of the starting load all
coming at once and lasting over this pe-
riod. Care should be taken in the opera-
tion of the plant that the motors are
started so that the starting load does not
all come at once.

The fixed price, or as it is frequently
known, the readiness to serve charge,
based on the horsepower of motors in-
stalled, is frequently a hardship and often
a charge which is not warranted by the
conditions of the plant; while at the
same time it is a fair charge in many
other plants. Take a plant, for instance,
which may have a very large connected
load, a small portion of which is in oper-
ation at any one time, and the readiness
to serve charge would frequently amount
to more than the total power bill of the
plant per month; or a plant where during
certain months of the year business is
rushing, the readiness to serve charge
may be a fair one during these periods,
but during slack periods the readiness
to serve charge would be excessive and
cnusc an actual h,ird«hip upon the plant.
The power companies take the ground that
this readiness to serve charge is only a

fair interest on the apparatus required to
furnish this power. At the price often
charged for this service, it would not only
represent interest, but also maintenance,
depreciation, and a good deal of the
operating charges on the machinery.

The minimum charge basis is also the
subject of a good deal of controversy, and
frequently the cause of hard feelings, as
the purchaser cannot understand why he
should pay for power when he does not
I'se it, and cannot understand the basis
upon which this charge is made. This is
frequently made a part of the fixed price
or the readiness to ser\'e charge, but at
times it is also made as a separate item.

As a rule the power contracts are writ-
ten by and for the power company in
such a way as to give everything to the
power company and leave as little as pos-
sible to the consumer. This is not un-
natural, because the intention is to pro-
tect the power company in every possible
way; and it is up to the consumer to see
that, from his side, equal protection is af-
forded him. This, however, the consumer
as a rule is unable to do, because he does
not know enough of the conditions to
thoroughly understand what the contract
means. It may be that any one signing
a contract that he does not thoroughly
understand, is foolish; but a large num-
ber of the power consumers take it for
granted that the contract is a fair one and
also are frequently assured by the sales
agent that the contract is a fair one. and
sign accordingly.

It is not infrequent to find that the
sliding scale is not well understood; and
upon the purchaser questioning the sales
agent, he is assured that this method of
charging is only a fair and just one which
is based upon the fact that the Small
user naturally would expect to pay a
higher amount for power than the larger
one, and attention is frequently called to
the very low rate for the power which
will be furnished, this being, of course,
to apply to the power above a certain
amount. This latter statement, however,
is not strongly called to the attention of
the purchaser. Attention is merely called
to this very low rate, without any stress
being laid on the fact that this applies
only to the power purchased above a
certain amount. When the bills are
rendered, the purchaser frequently finds
that they are very much higher than he
anticipated, and upon complaint, he is re-
ferred to the power schedule. He finds
that he has hardly reached during the
entire month that consumption which will
allow any considerable portion of his
power to be based on the minimimi
charge, and he frequently feels that he
has been misled, and frequently has been
misled, by the statements of the central
station agents.

10

POWER

July 4, 1911

A good many of the power contracts
are so arranged that the power company
has any number of chances of breaking
the contract if the conditions of operation
are not such as they desire, but very sel-
dom found to give an equal opportunity
to the purchaser. Some contracts recent-
ly issued are exceedingly unfair in this
particular, giving the power company un-
limited opportunities for failing to de-
liver power, for breaking the contract and
otherwise making trouble; while leaving
the purchaser absolutely powerless. One
contract agrees in one portion to deliver
continuous power, whereas in another
portion of the contract it is expressly
stipulated that during low water they may
not deliver power if water is not avail-
able. They are also allowed to hold the
purchaser to the contract even although
they f^iil to deliver power for a continu-
ous period of some months; whereas
there is no provision made by means of
which the purchaser can break the con-
tract. There is inserted a provision which
says that the party aggrieved may ter-
minate the contract, but it would puzzle
the judges of the Supreme Court of the
United States to determine wherein under
the contract the purchaser could be called
the party aggrieved, whereas practically
every clause allows the power company
to appear to be the party aggrieved.

Another contract has the power sched-
ule so arranged that it would puzzle a
corporation lawyer to determine whether
or not the bills were correct; and also
gives the power company the right to
charge for power on the basis of the me-
ter readings and gives the consumer no
provision to have these meters corrected
or make claim for overcharge if meters
are incorrect.

The purchaser of power should read
carefully the contract submitted by the
power company, and if any clauses are
not definite and thoroughly understood,
should submit the contract to an un-
prejudiced person thoroughly understand-
ing the conditions, for him to decide
whether or not the contract is a fair one,
and if necessary to write in such addi-
tional clauses as will thoroughly protect
the consumer.

After this has been done for a reason-
able period of time, it may be that the
central-station contracts will be brought
to a more uniform basis, and one which
will treat the consumer very nearly as
favorably as the central station. At the
present time contracts are all in favor
of the central station, and the consumer
signing them has little or no opportunity
for getting hack at the central station.

Contracts are, of course, a necessity,
as it is-only through some written agree-
ment that any dodging of the responsi-
bility or any misunderstandings can be
prevented. This does not mean, however,
that the contract should be so worded as
to be misleading or indefinite. The prime
requisite of a contract is to cover all con-

tingencies completely, accurately and
clearly, dealing absolutely impartially on
all matters under consideration, so that
each party to the contract be treated the
same. In order to do this it is absolutely
essential that the contract should be so
worded that it will be equally well under-
stood by both parties. Such is by no
means true of the contracts of most
power companies as now written.

Comparative Economy of Sat-
urated and Superheated
Steam
By Edw.^rd L. Jones

The following results were obtained
from tests made in the engineering labo-
ratory of Lehigh University by senior
mechanical engineers to show the gain in
economy by using superheated steam .

The engine used was of the vertical
reversing marine type, 8j-Sx5{J inches,'
with a 1,',,-inch rod, the clearance being
about 13 per cent. These are rather un-

either direction, as when running one
way the driving force would lift up on
the weight. It was found as an addi-
tional advantage, that the mass of the
weight aided greatly in eliminating ex-
cessive vibration of the scale pointer.

Each run was divided into ten six-min-
ute intervals, and speed counter • and
weight readings were taken at the begin-
ning and end of each interval, while in-
dicator diagrams, pressures, temperatures,
brake readings, etc., were taken at the
middle of each interval.

The tests show a marked gain in effi-
ciency for the superheated steam, and
the results of the two sets of runs
agree fairly well with each other. The
variation of the mechanical efficiency
may be due to the different setting of the
reversing lever.

Attention is called to the close agree-
ment of the indicated and the actual
steam consumption in both superheated-
steam tests. In calculating indicated
steam consumption the assumption was
made that the steam was saturated at the

DAT.A. AND RESTLT.^

Run number

Date

Duration

Position of reverse lever .
Revolutions per minute. .

M.E.P.. tieacf.

M.E.P., crank

Scale of indicator spring

Indicated horsepower, hd

Indicated horsepower, ck

Indicated horsepower, total

Brake load, net (lb.)

Brake horsepower

Mechanical efficiency (%)

Steam used per I.H.P. liour

Steam used per B.H.P. hour

Steam pressure, gage

Corresponding steam temperature

Observed admission temperature

Number of degrees of superheat

Exhaust temperature

Total heat per pound of steam at upper pressure and tem-
perature

Deduct for 2 per cent, of moisture

Deduct for water heat at free exhaust temperature

Heat used per lb. of steam

Work per lb. of steam (B.t.u.)

.\bsolute efficiency Cu,)

Indicated steam consumption per I.H.P. hour

Steam not accounted for by indicator, lb

Cylinder condensation {%)

Mar. 21
1 hr.

56.6

90.4

331. 5

330.0

super-
heated
Steam

Mar. 21
1 hr.

89. 0
330.5
479.6
149.1

6.97
36.5
negative

4.12
3. S3
7.95

53.2
8S.9
330.4
32S.9

2i9!5'

11S7.00
17.70
ISO

9S9.30
53.3

5. 38
35.2
12.1
25.4

Super-
heated
Steam

Mar. 22
1 hr.
*N.

179.3
28.4
23.1
40
4.65

52

7.32
87. 6
31.4
35.9
84.7
327.4
464.0
136.6
226.0

1258.00

ISO
1078.00
81.0

7.52
32.3
negative

usual proportions, but a partial explana-
tion is that the engine was originally
tandem.-compound, and the cylinder now
used for the simple engine was the low-
pressure cylinder of the compound.

For the superheated-steam tests, steam
was run through a separately fired In-
gersoll-Rand air reheater which was used
for heating both air and steam. The
engine exhausted into a surface con-
denser open to atmospheric pressure, and
the condensation passed thence into a
weighing tank. The power was absorbed
by a prony brake on a 36-inch wheel
with an arm 49' _> inches (4'<; feet) long,
and the force was weighed on a 200-
pound spring balance with a 100-pound
weight suspended from the knife edges.
The object of this arrangement was to
make it possible to run the engine in

points of measurement — shortly after cut-
off on the expansion cur\e, and near
the lower end of the compression curve —
but the point to be noticed is that the
indicated steam consumption under such
assumption is almost the same (slightly
greater) than the actual consumption as
determined by weighing the condensed
exhaust, thus showing the entire absence
of cylinder condensation, and the gain
in economy is no doubt due to that fact.

Announcement was recently made in
San Francisco that the Great Western
Power Company will build at Big
Me3dows% Cal., a reservoir that will be
the largest in the world, surpassing in
capacity the Roosevelt dam and reservoir
in Arizona, and the Assouan dam in
Egypt.

July 4. 1911

POWER

Notes on the Size and Care of Belts

Since a large percentage of the power
used in industrial plants is transmitted by
belts, everyone who has charge of trans-
mission equipment is, or ought to be, on
the alert to reduce, if possible, loss of
power, the number of new belts required
and the time lost in repairing old ones
to a minimum. A broken belt often will
delay the work of from one to fifty
men from ten minutes to an hour. Of
course, if a new plant is being designed
the transmission can be arranged to give
the best possible results. But if a man
has the conditions in an existing plant
to cope with he must be content to
eliminate the effects of poor design as
best he can.

Tight Belts
Tight belts are very often the root of
much trouble. A tight belt has a short

Fig. 1

life and produces excessive friction in
the bearings, and if too tight, it may
bend the shaft and injure the pulleys,
to say nothing of the loss of power which
it causes. There are various ways in
which to overcome this difficulty. If
the belt is a vertical one, or nearly so,
the angle to the horizontal should be re-
duced to 45 degrees, if possible. Figs.
1 and 2 show very clearly the disad-
vantages of an upright belt as com-
pared with a horizontal one; both have
the same tension, but, while the one in
Fig. 1 will transmit much power without
slipping, the one in Fig. 2 will scarcely
grip the lower pulley at all. Also, in
order to transmit the same amount of
power as the horizontal belt, the ver-
tical one must be made very tight. This
is especially true when the lower pulley
Is smaller than the upper. If they were
reversed It would be somewhat better but
still objectionable. If the power to be
transmitted were small and the belt larger
than would be required under ordinary
conditions, the results would be fair, A
guide pulley placed as shown in Fig. 3
would do much to help the belt to grip
the lower pulley, and even two such pul-
leys, one on each side, would be more
helpful.

If the tight belt is horizontal it will, in
most cases, be found to be too small to
carry the load and a larger one must be
used. After a belt is stretched to its
elastic limit it cannot be made any fighter.
In fact, no belt should be stretched to a

By W. R. WiUard

The disadvantages of tight
belts are considered and a
method given for comput-
ing tlie size of belt required
to transmit a given power
at a given speed.

point closely approaching its elastic limit,
but instead a good factor should be al-
lowed. The following method will be
found to give accurate results in finding
the width of a belt; .
Let

S = Speed of the belt in feet per

minute;
W := Horsepower to be transmitted;
P = Difference in the pull on the
tight and on the slack sides
of the belt.
Then,

p _ 33.0OO X H
S
Assume a case where it is required to
transmit 25 horsepower with the small
pulley 4 feet in diameter, running at 300
revolutions per minute, and that the arc
of contact of the belt on the small pul-
ley is 160 degrees. Neglecting slip, the
speed of the belt is the same as the speed
of the circumference of the pulley. This
would be

4 X 3.1416 X 300 — 3770 feet per minute
Substituting this in the formula
^.^.ooo y 2s

P = -

•;= 2 1 8.8 pounds

This is the difference in tension on the
tight and on the slack sides of the belt.
From the table it will be found that the

r.

Ratio ok Tensions,

T,

.\nKlc of

Ton lad.

IJpcrpcs

^•-0.3

F-OA

20

1 110

■ I. ISO

10

1.2.3.S

1.322

fin

1.36B

1..V20

so

l.MO

1.7S4

100

1.6S8

2 010

120

1.S7I

2. .Ill

140

2 OSI

2.6.18

160

2. til

SO.W

l.SO

2 .ifiO

3. an

200

2 K.IO

4.040

220

3.161

4 6 16

F r.-pr.-.
T, r.-i.r-
T, fl'f

III.' I.

i-frifiinl of friffion.
n'*inn on thn Itelit sHo
iiyion on the nlack siiln

ratio of these tensions is 2.311 if F be
taken as 0.3. Assuming that ordinary
single leather belting will pull with safety
80 pounds per inch of width, the latter
will be

If the belt has laced joints the safe
working tension may be taken from 250
to 350 pounds per square inch in sec-
tion. To find the safe tension per inch
of width of any belt it is necessary to
multiply this by the thickness. The pul-
leys should always be made as large as
possible, providing the speed of the belt
does not exceed about 4000 feet per
minute. A few belts have been run at as
high as 6000 feet per minute, but this is
uncommon.

Sometimes one wishes to make use of
an old belt and desires to know the
size of pulley to use, in which case the
following formula will give the correct
diameter:

„ _ ;»oo X //
RXAX IF
where

D = Diameter of the small pulley in

inches;
H = Horsepower to be transmitted;
/? = Revolutions per minute;
H'=: Width of belt;
A = Ratio of the arc covered by the
belt on the small pulley to its
circumference.
In some cases where the belt slips it
is more advisable to face the pulleys
with leather than to increase the tension.

2i8.8 Xz-.'jii
8o

=: 6? inches

Figs. 2 and 3

This will be found to give the belt 25
per cent, longer life and to increase the
friction considerably.

Care of Belts

In buying a belt it is advisable to get
it from a reliable firm and to make sure
that if has a close fiber and is very
pliable. The flesh side of a belt is always
the stronger and is less liable to crack;
therefore, it should be on the outside and
not next to the pulley. Oil, water and
dirt arc injurious to a belt and should
not come in contact with it at all. In
moist places leather should not be used
as it will stretch and rot. Where pos-
sible, belts should be run from the shaft
in opposite directions to relieve the pres-
sure on the bearings.

POWER

July 4, 1911

The Origin of Hydrocarbons Notes on Prime Movers

No problem in geology appears more
complex than that of the origin of the
numerous natural hydrocarbons — asphalt,
ozokerite, petroleum and natural gas. In
fact, geologists are at variance in their
theories as to the manner in which these
are produced. A great number of the
more important hydrocarbons found in
petroleums can be produced artificially
from organic substances, such as coal,
wood and fish oil, while identical or
closely allied hydrocarbons result from
the interaction of inorganic substances,
such as cast iron and chlorhydric acid.
In many places petroleum is closely as-
sociated with fossiliferous strata.

In Bulletin 401 of the United States
Geological Survey, entitled "Relations
between Local Magnetic Disturbances
and the Genesis of Petroleum," by
George F. Becker, the condition of knowl-
edge of the origin of petroleum and other
bituminous substances is reviewed. Some
oils, says Mr. Becker, are undoubtedly
organic and some are beyond question
inorganic. They may have been derived
from carbonaceous matter of vegetable
or animal origin, and they may have
been derived from carbides of iron or
other metals. It is also barely possible
that the hydrocarbons exist as such in
the mass of the earth.

While studying the subject, Mr. Becker
was led to inquire whether any relation
could be detected between the behavior
of the compass needle and the distribu-
tion of hydrocarbons. Not much could
be expected from a comparison of these
phenomena, for magnetite exerts an at-
traction on the needle whether this ore
occurs in solid masses or is disseminated
in massive rocks; moreover, many vol-
canic rocks possess polarity. On a map
of the magnetic declination in the United
States Mr. Becker found that the irregu-
larities of the curves of equal declina-
tion of the compass were strongly marked
in the principal oil regions. The most
marked agreement is found through the
great Appalachian oilfield, which is the
area of greatest variation in declination.
In California, also, strong deflections
accompany the chain of hydrocarbon de-
posits.

These observations are to some extent
also supported by conditions in the
Caucasus, where great magnetic disturb-
ances exist. While the theory of the
inorganic origin of the hydrocarbons as
exploited by various scientists is not
proved by this study, yet the contention
that great oil deposits are generated from
Iron carbides is strongly borne out by a
study of the map of magnetic disturb-
ances in the United States. The map
shows that petroleum is intimately similar
to those arising from the neighborhood
of substances possessing sensible mag-
netic properties, such as iron, nickel,
cobalt and magnetite.

The prime motive-power committee of
the National Electric Light Association
was appointed some time ago to consult
with manufacturers and station managers
for the purpose of keeping in touch with
the latest developments in the design and
operation of prime movers and their
auxiliaries. The report of this committee
for 1911 contains some interesting in-
formation, extracts from which are here-'
with given.

Stea.m Turbines

Erosion and corrosion were observed
in dift'erent types of turbines and in
various localities, but do not appear to
be common to any particular make nor
to any known set of conditions.

The manufacturers point out that this
action, which is apparently caused by
water of condensation being thrown by
the rotating element at a high velocity
against the stationary parts, may appear
extensive, yet do little harm. One in-
stance is cited where the engineer be-
lieved it would be necessary to rebore
the machine and reline it in order to
restore the assumed loss in efficiency.
But before doing this, tests were made to
determine how much the efficiency had
been affected and it was found that ap-
parently the efficiency had not been im-
paired. The explanation given for this
is that the slightly increased clearance
over the ends of the moving buckets per-
mitted the passage of water without caus-
ing friction. This seemed to indicate that
clearance between the tips of the rotat-
ing buckets and the inner wall of the
turbine casing is not detrimental to the
efficiency of the machine, at least w-here
water is present.

Regarding clearance, it was reported
by one manufacturer that with the five-
stage machine, when rubbing had oc-
curred it had taken place almost invari-
ably at the third stage. This indicated
that possibly the clearance at this stage
was insufficient, the practice having been
to make this clearance the same as that
on the first and second stages. As a
result the minimum clearance is now em-
ployed on the first stage and is increased
for each of the succeeding stages.

The Westinghouse Machine Company
reported some departures in design, chief
among which is the introduction of an
impulse element for the first stage, fol-
lowed by reaction elements for the rest
of the machine. Also higher rotative
speeds are being used, 3()00 revolutions
per minute being employed successfully
up to capacities of 2500 kilowatts and
1500 to 1800 revolutions per minute for
capacities up to 10,000 kilowatts. The
higher speeds are accompanied by smaller
dimensions and smaller parts which
lessen the effect of distortion and permit
a reduction in the clearance ratios.

The bleeder type of turbine has been

designed for use in industrial plants or
in combination power and heating plants
where it is desired that a turbine shall
operate with a good vacuum and also by-
pass a considerable quantity of steam
from the lower stages for heating or
other purposes.

Surface Condensers

Alany central stations are so located
that at certain seasons of the year the
circulating water is heavily laden with
refuse and foreign matter and obstructs
the condenser tubes. One central station
reported serious trouble of this kind
which was remedied by converting the
multipass condenser into one with a sin-
gle pass. This change resulted in pre-
senting three times the opening to the
flow of water and reducing the path of
the flow to one-third of the former dis-
tance. The same vacuum was main-
tained as before and the only appreciable
effects, outside of practically eliminating
the trouble, were those of a lower dis-
charge-water temperature and a larger
quantity of circulating water.

Reports from a large number of com-
panies indicated that the majority of
troubles with condenser tubes, such as
pitting, breaking, etc., are confined to
plants using sea water as the circulating
medium. In some cases, however, where
the water contains chemicals in solu-
tion or particles of carbon or iron oxide,
a local galvanic action is set up between
these and the zinc in the tubes. This
once started means spots of carbon from
which the zinc has been removed, and at
such points the action goes on until there
is a hole.

In some cases trouble was reported
from the condenser tubes creeping end-
wise, this often being sufficient to weai
away the shoulder on the gland and per-
mit the tube to come out of the tube
sheet. It would appear that this is caused
by the high velocity of the steam, as
the tubes which gave trouble were al
the top of the condenser. A suggested
cure for this trouble is to employ a spe-
cial gland for these tubes, one that will
screw into the tube sheet tightly, mak-
ing a vacuum-tight joint without packing,
with a groove on the inside of the gland
next to the tube. The tube can then be
rolled into the gland in a manner similar
to that in which a boiler tube is ex-
panded into the head.

Cylinder Oil

Much diversity appears in the practices
of different companies regarding specifi-
cations for cylinder oil where super-
heated steam is used. The viscosity re-
ported varies from 145 to 240, and the
flash point from 531 to 660 degrees. It
appears that the oils which should be
avoided are those having an asphalt base,
which tends to carbonize in the cylinders
at high temperatures.

July 4. 1911

POWER

13

Saving Effected with Pumping Engine

At a small pumping station in a sec-
tion of the country where coal is high,
a high-duty crank and flywheel pump-
ing engine was used to pump water di-
rectly into the city mains, the pressure
being maintained nearly constant by a
pressure-regulating governor. The speed
of the engine varied greatly at different
hours of the day and night, and during
the night there was so little water used
that it was often necessary to keep the
bypasses partly open, connecting the
discharge chamber with the pump cyl-
inder and thus preventing the pump
from stopping on dead center.

The chief engineer kept a log book in
which, among other things, was recorded
every hour the readings of the revolu-
tion counter. By subtracting successive

Discharge Chamber
^of Pump

By F. W. Salmon

Pine Wheel attached
to Valve Stem and
Wheel Mvith Steel Tape
on the Circumference

Fig. I. Device for Measuring the Valve
Opening

readings the number of revolutions for
any hour could be determined, and in
this way it was discovered that during
some hours of the night the engine made
more revolutions than during certain
hours of the day. This indicated clearly
to the chief that his night assistant had
been running with the bypasses open
more than was necessary. Accordingly,
he spoke to the night engineer about it
but was assured that the valves on the
bypasses were watched carefully and
were never opened more than was nec-
essary.

Although the apparent night pumpage
did fall off a little after this, the chief
was not satisfied; he wanted to know
how much of this apparent pumpage was
wasted power. This problem now con-
fronted him: How could this be meas-
ured '•'

He reasoned that if it were possible to
determine how much water was being
used at night in the city, the difference
between this and the apparent pumpage
would represent the bypassed water or
wasted power. A vcnturi meter would
measure this, but the expense involved
was too great; the game was not worth

The demand for water diir-
n;g tlic night was small and
ill order to keep the pump
riiiuinig, tlic bypasses were
partly opened. This rep-
resented a waste of power.
By an ingeniotis device this
waste wasmeasured and was
jound to be so great tliat
steps were taken to dispose
of the surplus water at a
small profit.

the candle. The chief then set about to
accomplish the desired result with com-
mercial accuracy for much less money;
and he succeeded.

The pump had four cylinders to each
of which was attached a I'. -inch by-
pass operated by a globe valve. The
chief procured four steel tapes, each
one meter long, and divided them into
centimeters and millimeters. On the
handwheels of the bypass valves he at-
tached a wooden disk about 12',. inches
in diameter and concentric with the
spindle. Around this was wound the
tape and the pointer was secured as
shown in the sketch. The whole attach-
ment cost less than $2 and it was pos-
sible to record the opening of each valve
to 0.001 of a turn.

The next time that the load was put
on the other pump, the chief had the
crank and flywheel pump opened and
examined carefully, the valves being
tested with water under pressure from

.60

0 100 eOO 300 400 500 600 700 800 900 1000
Rototlon of Bypass Valve Stem, Millimeiers

Fig. 2. Calibration Chart for Indi-
cating Devich

the other pump. Finding everything
tight, the bypasses were opened and the
pump started, running at various speeds
under the usual pressure of 110 pounds
and regulating the speed by the bypass
valves. The opening of each valve as
shown by the pointer and slecl tape
was recorded for each speed. This was
plotted as shown in Fig. 2. The pump
was then put on the mains and the other
pump was shut down.

That nighi the opening of each bypass
was recorded with the readings of the

revolution counter, and it was found that
over one-half the water apparently
pumped had passed back through the
bypasses.

A few days later the president of the
company strolled through the pumping
station, and the chief showed him the
data. ^X'hen the president asked why
the small direct-acting pump was not
used for night service, he was told that
the small pump had been found to take
more steam with the bypasses shut than
the large pump with the bypasses open.
The chief suggested that the surplus
water pumped at night might be sold,
with profit, even at a low price.

Therefore, arrangements were made
with the railroad company to supply its
tank (used at night for filling the tenders
of locomotives of freight trains) with
water at about S900 per year. With
this arrangement the total revolutions
per day were only from 90 to 100 more
than formerly.

At a recent meeting of the Physical
Society of London, President H. L. Cal-
lendar described and gave a demonstra-
tion of the action of the electric thermo-
regulator designed by him in 1897 for
experiments by the continuous electric
method on the specific heat of water.
The same type of regulator is now being
employed for measurements of the vari-
ation of the specific heat of water by a
new method in which two steady streams
at different temperatures are allowed to
mix, or share their heat, the resulting
temperature being observed.

A new chemical refrigeration process
due to Doctor Repin, a French chemist,
is claiiTied to be free from the defects
of the ammonia process, and to be spe-
cially adapted for economical results in
small plants. As is well known, in one
of the methods of refrigeration at pres-
ent in use, the cooling is effected by the
evaporation of liquefied ammonia. The
ammonia gas is recovered in water, which
absorbs large volumes, and when the
solution so formed is heated the am-
monia is expelled into a cooled receiver
and liquefied by its own pressure. A
serious difficulty is that about 25 per
cent, of water is carried with the am-
monia from the solution. The new pro-
cess, which is said to be free from this
trouble, uses sulphur dioxide as a re-
frigerant and camphor as an absorbent,
20 per cent, of naphthol being added to
the latter to prevent excessive foaming
and melting of the camphor on heating.
The sulphur dioxide is easily liquefied
and absorbs much heat in evaporating,
while it is entirely disengaged in gaseous
form from the camphor solutjqnj at a
temperature below the bofliiy point of
water. The I'n^iiierr. <

POWER

July 4, 1911

. . _ J

Care and Operation of Alter-
nating Current Dynamos

By Norman G. Meade

All switches should be open when an
alternator is not running. The machine
should be clean and free from oil and
dust at all times, especially from cop-
per or carbon dust. With a high-voltage
machine a small accumulation of dust on
the windings may be the cause of a seri-
ous burnout. In stations of sufficient
size to warrant the expense it is ad-
visable to install an air pump with a
line of piping to all machines; at each
machine a short section of hose is at-
tached to the pipe line to enable the at-
tendant to reach all parts of the winding
and blow out accumulations. The air
pressure used for such service should not
exceed 25 pounds per square inch; a
higher pressure may disturb the insula-
tion on the windings and blow dust into
the coils. Any accumulation of moisture
in the pipes must be blown out before
turning the air on a machine.

Each machine should be given a
thorough inspection occasionally. The
higher the voltage of the alternator the
more often should this be done.

Ventilation

In their latest form, turbine-driven al-
ternators are entirely inclosed. A fan
in each' end drav;s cool air from an out-
side source and forces it through and
out of the machine by way of an outlet
at the bottom of the frame. This air
should be drawn through suitable piping
from some source outside the building
to eliminate dust and dirt and to secure
a low temperature. Inclosed turbo-gen-
erators require about four cubic feet of
air per minute for each kilowatt of capa-
city. The velocity of air in the intake
pipe should be from 600 to 1000 feet
per minute. Special precaution should
be taken that the warm air from the ma-
chine does not escape into the intake
passages. This ventilating arrangement
serves the twofold purpose of keeping
the machine cool and of preventing un-
due accumulations of dirt and oil.

It is advisable to remove the hoods
over the ends of the machine at inter-
vals and give the interior a thorough
inspection and cleaning. The ventilating
ducts in the field magnet which are paral-
lel to the shaft are liable to become
obstructed with oil-soaked dust. Care
must be exercised to prevent the accumu-
lation of dirt there because if the ducts

become choked the revolving element
will heat rapidly and the field winding
may be damaged. When an ordinary air
blast is not sufficient to remove the dirt,
it must be forced out with a wire brush
or rod. The radial air passages which
lead to the periphery of the magnet are
not usually subject to this difficulty be-
cause centrifugal force tends to keep
the passages clear.

Brushes, Rings and Commutators

The collector rings must be kept clean,
smooth and true. To prevent cutting, a

Half Segment

Setting of Rectifier Brushes

little vaseline should be applied occasion-
ally. The rectifying commutators of com-
pensated alternators should be kept
smooth by the occasional use of No. 00
sandpaper. Commutator lubricant should
be applied to high-voltage alternators
with a piece of cloth attached to the end
of a do' stick. If the commutator be-
comes at all out of true it should be
turned down. In the case of revolving-
armature generators this can be done
without removing the armature from the
machine by the use of a special slide
rest and by running the engine ver\'
slowly; or the commutator may be taken
off the shaft and turned down in a lathe.
On most modern alternators carbon or
soft graphitic brushes are used to con-
duct the exciting current to the collector
rings. These brushes are usually mounted
perpendicularly to the surfaces of the
collector rings; they fit closely and re-
quire little attention beyond occasional

rci.twa! and casual inspection from time
to tinie to see that they fit properly. Soft
graphitic brushes have been found to
give the best results as they are less
likely to chatter.

On some of the older types of al-
ternator copper brushes reinforced by
brass plates are in use. Care must be
taken to prevent the brass plates from
coming in contact with the collector ring;
if they do, cutting will result.

The copper brushes used in conjunc-
tion with the commutators of alternating-
current generators with compensating
windings are beveled and bent into proper
shape before being shipped, as indi-
cated in Fig. 1, which shows the correct
setting of such brushes on a commutator
with ten segments. The space between
the brushes depends upon the location of
the brush-holder studs. The brushes are
set one, three, or five segments apart, on
different machines; the operation of the
commutator will be the same electrically
as long as the brushes are an odd num-
ber of segments apart. The forward
brush in each holder should be given a
lead of about one-half a commutator seg-
ment ahead of its companion.

The brushes should bear upon the com-
mutator with light but good contact, the
leading brush having slightly less pres-
sure than the trailing brush; too great
a pressure will lead to heating and cut-
ting. It is well to place one set of
brushes a little further from the shaft
bearing than the other in order that any
ridges formed by one set will be worn
away by the brushes of the other set
before they become perceptible.

It is advisable to set the trailing
brushes exactly in position while the gen-
erator is at rest, and when once set they
should not be changed. Sparkless com-
mutation can only be obtained when the
brushes are set in this correct position.
The leading brushes may be changed
relatively to the trailing brushes while
the machine is in operation.

The compounding of the alternator may
be varied by shifting the brush-holder
rocker and also, to a slight extent, by
changing the spread of the brushes in
each holder; increasing the spread de-
creases the compounding and vice versa.
When the rocker is shifted to give the
proper compounding, all brushes may be
made to run sparkless by changing their
spread. The practical limits of this ad-
justment are when the brushes span one
commutator segment, in which case the
compounding winding is short-circuited,
and when all the brushes of each stud

July 4, 1911

POWER

are in line, in which case the compensat-
ing winding will be open-circuited.

If the generator is running on a non-
inductive load or on a load with a con-
stant power factor, the brushes may be
permanently set for a given regulation.
If, however, the power factor varies, it
will be found necessary to adjust the
brushes occasionally. The higher the
power factor, the less compounding will
be necessary for a given regulation and
vice versa. With a widely varying in-
ductive load it is impossible to adjust
the brushes so as to obtain absolutely
sparkless operation.

Sparking at the rectifying commutator
may be due to any of the following
causes: The brushes may not be set at
the proper point for commutation; a posi-
tion can always be found where there
is no appreciable sparking and at this
point the brushes should be secured.
The brushes may be loose or may not
be bearing sufficiently on the commutator,
or may be welded at the end. They may
be spread at the end, or the commutator
may be rough. The commutator may be
dirty or oily, or copper dust may have
collected on the insulating segments.
The generator may be overloaded. The
compensating circuit may include a loose
contact or be actually open.

Bearings

Modern alternators have self-oiling
bearings. These should be filled to such
a hight that the rings will carry suffi-
cient oil up to the shaft. If the bear-
ings are too full, oil will be thrown out
at the ends. The oil should be renewed
about once in six months, or oftener if
it becomes dirty and causes the bearings
to heat.

The bearings must be kept clean and
free from grit. They should be frequently
examined to see that the oil supply is
properly maintained and that the oil rings
do not stick. New oil should be run
through a strainer if it appears to con-
tain any foreign substance. If the oil is
used a second time, it should first be
filtered and, if warm, allowed to cool.

If a bearing becomes hot, heavy lubri-
cant should be fed into it copiously and
the nuts loosened on the bearing cap;
if the machine is belt connected, the belt
should be slackened.

Belts

The belt of a belt-driven alternator
should be tight enough to run without
slipping but the tension should not be
too great nr the bearings will heat. Belts
should nin with, not against the lapping.
The joints should be dressed smooth so
that there will he no jarring as if passes
over the pulley. The crowns of driving
and driven pulleys should be alike;
"wabbling" of belts is sometimes caused
by pulleys having unlike crowns. A wave
motion or flapping is usually caused by
slippage between the bell and pulley, re-

sulting from grease spots, etc.; this fault
may sometimes be corrected by increas-
ing the tension but a better remedy is
to clean the belt. A back-and- forth move-
ment across the pulley face is caused by
unequal stretching of the edges of the
belt.

It sometimes occurs on belted ma-
chines, especially in dr>' weather, that
charges of static electricity on the belt,
which may be of quite a high potential,
cause discharges to ground. If the frame
is not grounded, these charges may jump
to the armature or field winding and
thence to the ground, puncturing the
insulation.

General

If a line fuse blows or a circuit-breaker
opens, the switch corresponding to that
line should be opened and the fuse re-
placed or the circuit-breaker closed. The
switch should then be closed. If the
circuit opens the second time, there is
something wrong on the line — probably
a short-circuit — and this should be cor-
rected at once. If a short-circuit oc-
curs at or near the machine, or if an arc
be formed at a switch or fuse block and
holds on, all field-regulating resistance
should be thrown in at the rheostats.
If necessary, the field switch should be
opened and if this does not stop the
trouble the machine should be shut down
at once.

Before starting up any alternator, it
should be clean. The bearings should
be well supplied with oil and the oil
rings free to turn. The machine should
be brought up to speed and the rheostat
turned so that all the resistance is in
the field circuit and the field switch
closed. The rheostat of the exciter should
be adjusted for the normal exciting volt-
age; then the voltage of the alternator
raised point by point to its proper volt-
age by cutting out the resistance of its
field rheostat. The load can then be
thrown on.

Any of the following causes may pre-
vent an alternating-current generator
from developing its normal electromotive
force: The speed may be below normal;
the switchboard instruments may be in-
correct and the voltage may be higher
than that indicated, or the current may
be greater than is shown by the am-
meter; the voltage of the exciter may be
low because its speed is below normal
or because itS' series field winding is
reversed; the brushes of the exciter may
be incorrectly set; a part of the field
rheostat or other unnecessary resistance
may be in the field circuit.

To shut down a machine operating
alone, the field current should be reduced
as much as possible by means of the
field rheostat and the load thrown off
by opening the feeder switches or main
generator switch, if one be used. Next,
the exciter circuit should be opened and
Anally the machine shut down.

Fisliing Line and a Pheasant
Cause Trouble

A peculiar cause of ground was recent-
ly found on a 66,000-volt line. The
series relay at the station gave trouble
during the early morning hours by com-
ing out. The trouble patrol finally dis-
covered that a fishing line had been hooked
over one of the top wires and hung
across several others, and touched the
ground, as shown in the accompanying
illustration. The wet condition of the
fishing line, caused by the dampness of
the night air, had reduced its electrical
resistance sufficiently to enable the enor-
mous electromotive force to drive through
it an appreciable current to the ground;
this leakage current had opened the relay.

It is the practice of the company op-
erating these hich-ter.sion lines to send
out a trouble man to locate any disturb-

PosiTioN OF Fishing Line that Caused
THE Trouble

ance of the circuits. One evening the
relay on one of the lines came out and
the next day the trouble man discovered
that a pheasant had, in flying between
the wires, touched two of them with the
tips of its wings and caused a slight
short-circuit. The pheasant was instant-
ly killed. The incident had been wit-
nessed by a railroad employee, who took
the bird home to furnish a portion of
the evening meal. When the bird was
cut open, however, it was found that the
electrical current had turned the flesh
green.

POWER

July 4, 1911

Kilovolt Amperes

What and why are kilovolt-amperes?
This question is asked at frequent inter-
vals, notwithstanding Jones' painstaking
efforts* to explain the effects of phase
displacement in alternating-current cir-
cuits. Volt-amperes are volts X amperes
and a kilovolf-ampere is 1000 volt-am-
peres, because kilo means a thousand-
fold.

In a direct-current circuit, volt-amperes
are exactly the same as watts because
the current and electromotive force are
steady and it is therefore impossible for
them to be out of phase with each other.

In an alternating-current circuit the
volts and amperes rise and fall many
times per second; if they rise and fall
exactly in unison, both reaching their
maximum values at the same instant, they
are "in phase" and the power factor of
the circuit is 100 per cent. That is, all
of the power represented by the current
and pressure is available power. Then,
volts X amperes, or volt-amperes, are
equal to watts; consequently, kilovolt-
amperes are kilow-atts.

When the current and pressure do not
rise and fall exactly in step with each
other, the power factor is less than 100
per cent, because when the current is
maximuiTi the voltage is not and when the
voltage is highest the current is not; con-
sequently the maximum combined effect
of the two cannot be obtained and it
is the combined effect that makes power.
Pressure that exists today cannot be
combined with current that exists tomor-
row; similarly, pressure that exists at one
moment cannot be combined with current
that exists a hundredth of a second later.

If at one instant the pressure is at its
maximum of, say, 100 volts and at that
same instant the current has reached only
800 amperes, the instantaneous power is
100 X 800 = 80,000 watts. If the cur-
rent reaches its maximum of' 1000 am-
peres, say, when the pressure has dropped
to 80 volts, the instantaneous power is
again 80,000 watts. But under these con-
ditions the maximum power of 100 X
1000 =^ 100,000 w;atts can never exist,
because the pressure and voltage do not
reach their highest values together.

The true power (watts) is the mean
(the quadratic average) of the many
instantaneous power values which exist
during the alternations of the pressure
and current. As the instantaneous power
never reaches the possible maximum, the
mean power cannot be the full value rep-
resented by merely multiplying the pres-
sure and current together; that gives
the volt-amperes and volt-amperes may
or may not represent power. If a cur-
rent of 1000 amperes lags behind a pres-
sure of 100 volts by one-quarter of a
cycle, there are 100,000 volt-amperes in
the circuit but absolutely no available

21, 1011.

2GS. Kp1)iMinry 14, and 454, March

power because the power factor is then
0; when the pressure is maximum the
current is at zero in its cycle and when
the current is at its highest point the
pressure is at zero.

The power factor of a circuit is the
proportion of apparent power (volt-am-
peres) that is actual, available power
(watts). If a current of 1000 amperes
lags behind a pressure of 100 volts by
a full tenth of a cycle, the power factor
is 80 per cent. Therefore, although the
volt-amperes are 100,000, the real power
is only 80 per cent, of that, or 80,000
watts.

Having the usual voltmeter and amme-
ter together with either a wattmeter or a
power- factor meter, the characteristics of
a circuit can be determined, because

Volt-amperes X Power factor — Watts
and therefore

Watts -^ Volt-amperes = Power factor.
In considering power-factor values it
must be kept in mind that they are per-
centages. When anyone says the power
factor is 80, he means 80 per cent., or
,'„», , and that means that the real watts
in the circuit are i",,",, of the apparent
watts, or the volt-amperes.

LETTERS

T\\'()-phase and Tliree-phase
Alternators in Parallel

Referring to D. M. Grove's recent in-
quiry as to whether he can operate a
two-phase alternator and a three-phase
alternator of the same voltage and fre-
quency in parallel through a two-phase
three-phase transformer. I wish to point
out that there are several difficulties to
be overcome in order to obtain reliable
operation that way. The Scott connection
of transformers shown in Mr. Grove's
diagram gives voltages which are sub-
ject to distortion, not only when the sec-
ondary loads are unbalanced, but also
w'ith a balanced noninductive load; hence
this method would be the source of more
or less trouble.

The three-transformer arrangement for
changing three-phases to two-phases, or
vice versa, shown in the accompanying
diagram, is superior to the two-trans-
former scheme in its greater freedom
from unbalanced voltage and larger "fac-
tor of safety" for continuity of service.
If one of the transformers of the Scott
system should become inoperative, only
one phase would remain active on either
the two-phase or three-phase side; con-
sequently, the whole system would be
out of commission until a new trans-
former could be installed. Therefore, in
order to insure continuity of service, a
spare transformer must be carried in
stock. If one of the transformers in
the three-transformer system should he-
come inoperative, the two remaining ones
can be temporarily V-eonnected and will
carry the load until the damaged one is

repaired. If it should be considered
preferable to keep a spare transformer
in stock, its rating is only two-thirds
that of a spare transformer for the two-
transformer system.

When the three-transformer system is
used, however, the armature windings
of the two-phase generator must be in-
dependent, because destructive local cur-
rents would be produced in the windings
if they were interconnected.

It is practical to operate the two ma-
chines in parallel with the field winding

Connections for Phase Changing with
Three Transformers

of the two-phase machine left just as it
is. Each machine will do its share of
the work irrespective of what the field
strength may be, the division of the load
being determined by the relative free
speeds of the prime movers.

In an ordinary alternator there are two
sources of field excitation: the current
in the field winding and the current in
the armature winding. To produce a
constant voltage the sum of these two
excitations must be constant. Now the
excitation due to the field winding of
the two-phase machine varies with the
load on account of the compensating
winding, whereas variations in load will
have no effect on the ampere-turns in the
field winding of the three-phase ma-
chine. Hence, any changes in the load
currents of the two machines will cause
a cross current between the two arma-
tures and circulating in the armature
windings in such directions as to
strengthen the field of the weaker ma-
chine and oppose the field magnetism of
the stronger machine, thereby balancing
the voltages of the two machines.

To eliminate cross currents, the field
excitation of the three-phase machine
will have to be adjusted to correspond
with that of the two-phase machine, and
if the variations in load are not too rapid
or of too great magnitude, the attendant
could do this by means of the field
rheostat. However, for rapid variations
in load it would be advisable to install
a Tirrill voltage regulator in connection
with the three-phase machine, adjusting
the compensating winding of its alter-
nating-current magnet to give the three-
phase machine the same rate of com-
pounding that the two-phase machine
has.

Hamilton, O. S. H. Harvey.

July 4, 1911

POWER

Experiences with Large Gas
Engines in Steel Works

During the sessions of the Gas Power
Section of the American Society of Me-
chanical Engineers, at the recent Pitts-
burg meeting, there was a semi-informal
and highly interesting discussion of the
results obtained with large gas engines
in steel works. The supervising engi-
neers of several of the large plants of
this country presented their views with
an unusual degree of freedom and com-
prehensiveness. Very full abstracts of
these utterances are giv, n herewith.

By E. a. MacCoun*

It is on account of the large expense
for repairs, high first cost and extra com-

C. I. Bushing

Fig. 1. Cylinder Used at Thompson Works

trie unit (40x54 twin-tandem engine) ran
75.87 per cent, of the year.

Figs. 1 to 12 inclusive show some of
the improvements we have made in the
constructional details of our engines. Cyl-
inder troubles have not yet been entirely
overcome. The greatest difficulty is the
liability of the cylinder to crack and al-

.Jci'nt IJgS.

water to leak in from the jacket.
Both iron and steel have been used for
cylinder castings. I greatly prefer steel
because of the thinner wall, which in-
creases the cooling effect and thereby

Fic. 2. Cross-section at Exhaust-valve
Chamber

plications of gas engines that some steel-
works managers hesitate to install more
of them. Excellent results are being ob-
tained in the way of reliability. During
I9I0 one of our .V?x54 twin-tandem blow-
ing engines ran W1.,^ per cent, of the year
and the other one 90 per cent.; the elec-

Fic. 3. AxiAi. Section at Exhaust-valve
Chamber

helps to prevent metal fatigue; but this
does not eliminate the liability to crack.

Fig. 1 illustrates the construction of a
cast-steel cylinder we have had in ser-
vice for two years and Figs. 2 and 3 are
partial sections through the same cyl-
inder.

Fig. 4 shows the type of piston now in
use. It is made of cast steel and has

never given any trouble. It will be
noticed that its contour is an approach
to a sphere; this gives enormous strength
and allows for expansion. There is no
agreement between builders as to the
number or type of piston rings that
should be used. We prefer to use not
more than four rings of the sectional
type, with keepers, with good depth and
wearing surfaces. Rings should not be
doweled in place, because the dowel pins
are liable to come out and cut the cyl-
inder wall.

It is most difficult to make a piston rod
strong enough to stand the pressures de-
veloped in large engines. Some rods are
as large as 13 inches in diameter and it
is nearly impossible to increase the size
to any great extent. Piston rods are
fastened to crossheads by keys through
the rods or by threads with either nuts
or clamps over them. The thread with
a clamp over it appears to be preferable;
the keys and nuts have given consider-
able trouble. Nickel steel was first used
in our piston rods but it was found un-
reliable. A more satisfactory material
is open-hearth steel of the following
composition:

IVr cm I.

Carbon 0.4."> to O.C.O

Man-^iint'se 0.4.5 to o.({0

riieisplioius under 0.04

Snlpliiii- under o.(i4

Sill, DTI II. HI I..CI.-JII

This steel to be heated to get 50,000
pounds per square inch elastic limit, 95,-

-One Piece
Bronze Water
Fitting

Three.Slots,

supporting

anarcmorin^

Core

Fig. 4. Cast-steel Piston

000 pounds ultimate strength and 12
per cent, elongation in 2 inches. No
trouble has been experienced by the
wearing of rods made of this steel. We
have been compelled to line all piston
rods wiUi brass tubing on account of the
acid in the cooling water, taken from the
Monongahcia river. We had to abandon
holes through the sides of the rods for

POWER

July 4. 1911

the entry and exit of water on account
of the cracks that developed; the water
is taken in and discharged through the
ends of the rods. Figs. 5, 6 and 7 show
the constructional details of the pi:ton
rods and connections now in use, which
seem to be satisfactory.

The cylinder heads gave some trouble
at first, but this has been eliminated by
changing the design as illustrated in
Figs. 8 and 9.

Many improvements can be made in

Lock for Nuf

Shape of Original
Hole In Rod \

load conditions than constant mixture.
Figs. 10 and 11 are diagrams taken from
engines using the two systems, ranging
from no load to full load.

Our exhaust valves have given very lit-
tle trouble and do not have to be ground
in very often. Fig. 12 shows the valve
in use on our engines.

By R. H. Stevens*

At the Carrie furnaces we have four
Allis-Chalmers gas-blowing units and five

Thickness Plate

'Plug used in

^Original Rod

'Brass Wafer
Outlet Connection

Original Hole in
Rod ihown by
dotted Lines

Differential-
Nut, Buttress Thread

By a. M. Diehl*

Blast-furnace gas after leaving the
furnace passes first through the dust
catcher, where the heavier particles are
deposited by their own weight, which is
facilitated by the reduction in the veloc-
ity of the gas. Beyond this point, a
number of washing systems of cleaning
have been proposed, but none of them
is very efficient unless used as an auxil-
iary to a cooling apparatus for the re-
moval of moisture, because the tempera-
ture is so great that the gas will pick up
moisture again and the good effect of
clean gas is destroyed by the excessive
moisture.

/ Pipe to Overflow Box
Fig. 5. Improved Piston-rod Connections

'■^Av^'l either cracked
^^^^ orctjt through and
Bushinq pressed in
ana doweled

Fic. 8. Old Cylinder Head

the inlet-valve gears of engines working
on blast-furnace gas. The essential re-
quirements for satisfactory working are
as follows: The wear on all parts should
be taken up easily by adjustment; am-
ple surfaces should be provided on all
wearing parts to prevent rapid wear and
distortion of the valve setting; each valve
on the engine should be adjustable in-
dependently of all the others; the valve
gear should be so made that the relative
openings of the gas and air ports can
be changed either individually or col-
lectively, and it should be possible to
make these adjustments very quickly, to
meet sudden changes in the quality of
the gas.

Bronze Castinq
fastened to End of Rod .

■' I Pipe Tap

■^^fp<-' Inlet Water to Piston
iv x-x-Ti from A rm clamped

electric units; three of the latter engines
are Allis-Chalmers and two of the Beth-
lehem Steel Company's make. The gas
from the furnaces first goes through a
Babbit impinging washer; then through
a fan into a screen, from the screen into
the Theisen washer and thence to the
engines. We get a total efficiency in the
cleaning of over 99 per cent.; the im-
purities are reduced as low as tu'T.u of
a grain per cubic foot. Our engines
take about 110 to 120 cubic feet of gas
per indicated horsepower and the gas
ranges from 85 to 90 B.t.u. per cubic
foot.

Our gas blowers have been in shape to
operate at least 95 to 98 per cent, of the
time that has elapsed since they started.
The demand, however, was such that we

About tI
Opening for
pinching Rod ^

Babbitt^

Fig. 6. Inlet-vcater Connection to
Piston Rod

Many of the valve gears now in use
meet most of these requirements but
none of them, so far as I know, satis-
factorily meets the last one, which is very
important.

We have found the constant-compres-
sion system of governing better for all

^, Water
^'Outlet

Fic. 7. Outlet-water Connection to
Piston Rod

only ran approximately about 90 per cent,
of the elapsed time. We are getting gas
that is cleaner than the air. We do not
use the fans in connection with the clean-
ing system; we bypass them.

We have obtained the best results
by positive and repeated spraying in a
tower 76 feet high and 12 feet in diam-
eter, supplied with water at one level
about 10 feet from the bottom and at
another about 30 feet higher. At each
level the water is fed into a distributing
valve having a revolving core which is
rotated by a 5-horsepower motor. The
two valves are located outside the tower
and each has 12 openings from which
1 '4 -inch pipes extend to spray nozzles
in the tower. These nozzles are lo-
cated so as to cover the entire cross-
section of the tower; they point upward

ffibs or
cnnections here

' j Depression to prevent :
' Valves from Striking

Fig. 9. New Cylinder Head

and deliver the water against a screen
about 6 inches above them which breaks
the water up into a fine mist.

The core of each distributing valve
always closes two of the openings and

•Superintendent of furnaces. Duquesne
works of the Carnegie Steel Company.

J

July 4, 1911

POWER

19

leaves the other ten open and its rotaiy
motion causes the openings to be closed
successively in pairs. At the moment
when one pair of nozzles is shut off, the
gas surges through the space around
them because of the lower resistance
there to its passage; a moment later
these nozzles are opened again and the
next pair closed, and the renewed sprays
pass through the gas above them and tend
to drive the column over to the area
belonging to the nozzles that are now
shut off. This tends to give the ascend-
ing column of gas a spiral motion which
increases the efficiency of the scrubbing.

A speed rate of 15 revolutions per
minute is about right for the distributing
valves. The upper and lower valves
are arranged to overlap each other. This
arrangement has proved superior to a
revolving spray located at the top of the
tower, in both cleansing and cooling
ability. From the towers the gas passes
to Theisen washers, thence to a spiral
drier and to the main leading to the
engines.

The engine equipment consists of two
twin-tandem Snow power engines and
four blowing units; all of the cylinders
are 42x60 inches. The electric generators
are rated at 2000 kilowatts each and on
an average load of 1372 kilowatts during
the last six months of 1910 the engines
showed an average thermal efficiency of
24.15 per cent.

The engines are cleaned about once
every two months; we have never
stopped an engine to clean the cylinders
or pistons, but the jackets become clogged
with mud and leaves from the river
and when we clean them the cylinders
and pistons are also cleaned. About
once every six hours two charges are
allowed to blow off through ports lo-
cated in the bottoms of the cylinders.

During the past six months the en-
gines have operated 98.8 per cent, of the
time that they were actually required
(not the elapsed time), but less than
one-half of 1 per cent, of the time loss
wis due to the engines themselves, the
remainder being due to the blowing-tub
drive.

By H. L. HoERRt

The National Tube Company's plant at
McKeesport contains two twin-tandem
Allis-Chalmers engines with cylinders 32
inches bore and 42 inches stroke, each
driving a lOOO-kilowatt electric generator
at 110 revolutions per minute. The
dynamos are direct-current machines and
are operated in parallel with others
driven by steam engines.

Many difficulties were encountered at
first and for a while the situation was
discouraging. After making a good many
changes in the engines, most of them
■light, they are operating as regularly
»8 any of the other units in the plant.

tStPBm ami hvdrnnllr nig\ntvT. National
Tnhp rompany, McKeenport, Peno.

Some of the constructional features that
gave trouble in this plant are giving sat-
isfaction in other places. The changes
that were made are as follows:

The piston cooling water connections
changed from swinging joints to tele-
scopic joints; igniters changed from
rotary to vertical motion (this restricts
the location of the igniter to the top of
the cylinder); spur gears put in place
of spiral gears to drive the cam shaft;
connections between exhaust valves and
mufflers provided with expansion joints;
piston changed from cast iron to steel
and rings changed to eliminate the keep-
ers that held the rings in place (these
keepers caused cylinder cutting which
necessitated the bushing of three cylin-
ders) ; piston-rod packing rings made of
babbitt instead of cast iron, except the

tice which obtains at the plant should
not be construed as meaning that a gas
engine is necessarily the proper prime
mover for such a works. I am inclined
to believe, without having definite and
complete data, that the cost of the gas
engine in the first place and the cost of
its maintenance in the second place are
so heavy that steam can still compete
with it very successfully in the districts
where coal is cheap. I am not able to
submit detailed figures to prove this, but
in order that the figures and the facts
given in the operation of this plant may
not be misconstrued, I w-ish to add the

'Vl

Fin. 10 Diagrams from Engine Governed by Throttling Mixture

"fire" ring; a slight change in the form
of the exhaust-valve chamber to prevent
internal stresses in the castings.

During 1910 one engine ran 89 per
cent, and the other 91 per cent, of the
total elapsed time, and there were four
months when no delays were chargeable
to the former engine and six such months
for the latter one.

The gas is practically free from dust
when it leaves the final Theisen washer;
a sample of 100 cubic feet contained
only 0.23 of a grain, total. The water
used bv the gas-cleansing plant averages
lO.";.? gallons per 1000 cubic feet of gas
cleansed.

I would like to add that the good prac-

opinion that we can still use steam in
this district at a lower cost than for gas
power.

Bv H. .1. K. FREYNt

The previous speakers have tried to
convey the idea that possibly the gas
engine was not the right one to use, but
in the same breath they gave us fig-
ures lilf.^ 9.'^ and 99 per cent, running
time and said no delays were charged
to them for six months and four months,
and so forth.

In the Gary plant, on the shore of Lake
Michigan, which is driven entirely by gas

lAmilfilant pnglnwr of rotmtnirllon. Illinois
8t«el Company. Smith Chicago. III.

20

POWER

July 4, 1911

engines, only 25 per cent, of all delays
have been charged against the engines.
The engines have run on an aver-
age service factor of 33 per cent.,
vifhich is about equal to the service fac-
tor of any of the large power plants in
New York, Boston or Chicago. I am
unfortunately not in a position to give
you today any actual figures relative to
the cost of operating these gas engines,
but I can tell you that when the Gary
plant is compared with a big steam-tur-
bine plant having a service factor of 30
to 38 per cent., the cost of operation
at Gary looks very, very good, notwith-
standing the fact that the American gas
engine is a very recent development in
the line of prime movers.

The assistant general superintendent
of the Illinois Steel Company recently
went to Europe and while there he saw
the blast-furnace gas-engine installation
at a large German steel plant. When
he returned he expressed the opinion that
we are mere amateurs in gas-engine
work in this country. He told me that
there was a marked lack of trouble;
there was in fact no trouble at all. I
was in Europe last year after an absence
of four years and I was surprised to
see how wonderfully the gas-engine in-
stallations operated. The gas-engine de-
velopment started in Europe about 1899,
and I had the pleasure of being con-
nected with the birth of the large gas
engine. Five or six years ago, in an
assemblage like this you could have
heard exactly the same things we have
heard about cylinders cracking, piston
rods breaking and all kinds of troubles,
but if you go over there today you will
not hear anything about those troubles,
because they have been worked out in
the meantime. The gas engine is not
as far advanced in America as in Europe,
because only four or five years have
elapsed since the first large gas engine
was installed and operated here.

Mr. MacCoun seems to think that gas
engines are successful only in smaller
sizes; there are in operation abroad gas
engines of 48 inches cylinder diameter
and 55 inches stroke, running at 80 to 90
revolutions per minute. 1 have seen a
twin-tandem double-acting gas-engine
unit of 4000 kilowatts operating on
blast-furnace gas.

The cost of repairs is very high, and
we have had a lot of trouble. We ad-
mit it. But the latest installations of
large gas engines — the Snow engines at
South Chicago and Duquesne and the
Allis-Chalmers and Westinghouse en-
gines at Gary — are operating without
any big repairs; the cost of repairs and
of operation is coming down here just
as it has in Europe.

Mr. MacCoun said it is almost im-
possible to design piston rods strong
enough to stand the terrific strain of
gas-engine work. American piston rods
are 28 to 33 per cent, of the diameter

of the cylinder; in Germany they are
not more than 25 or 26 per cent. There
are nickel-steel piston rods over there
containing as much as 5 per cent, nickel,
which would be considered absolutely
prohibitive in this country.

Many constructional details which have
given trouble in this country have never

The solution in this country seemed to
be to put in cast-steel cylinders, and
there are several in successful operation.
There is not a single steel cylinder in
use in Europe, even in 48-inch diam-
eters. The reason, as far as I can learn,
is that the foundry practice over there is
a little different and better than here.
The steel cylinder has not met with
great success abroad, because of the fact
that while the modulus of elasticity of
cast steel is much higher than that of
cast iron, the coefficient of elongation
by temperature is very much higher. The
product of the two factors, which is
called the coefficient of quality, is there-
fore about the same for the two metals.
In other words, the greater elongation
due to temperature in the steel cylinder
offsets the superiority in the modulus of
elasticity.

We have also arrived at the cast-steel
piston in this country, and I fully share
the views of everybody in regard to the
use of cast steel. Therefore I was sur-
prised to see 48-inch cast-iron pistons
in use abroad without cracking.

'Collar fo prevent
D/rfgenlng on

Fig. 11. Diagrams from Engine Gov-
erned BY Changing Mixture Quality

given any in Europe; the only differ-
ence is in the workmanship. What we
need in this country is better workman-
ship, and there is no doubt that we are
going to get it.

There have been a great many cases
in this country of large cast-iron cyl-
inders cracking. So they did in Europe.

Four,

Wafer Outlet

Fig. 12. I.mproved Forms of Exhausi
Valve

The packing of piston rods has given
a great deal of trouble in this countr>',
but the packings now made are good
and I believe we are ahead of the Euro-
peans on the packing question, because,
while European packings are doing well,
they are very complicated.

I used to be a very stanch adherent
of the constant-compression or "quality"
principle of regulation, but I do not think
it is much of a system now, since I
have seen engines in operation with vari-
able compression, running electric gen-
erators without any pounding and with-
out any trouble.

Mr. Bacon, of the Illinois Steel Com-
pany, and I have investigated the com-
parative costs of installing gas-power
and steam-power plants, and while we
cannot give out the results now, I can
tell you that statements that have been
circulated to the effect that the cost of
a gas-power installation is SI 25 a kilo-
watt are not true at all. The cost of a
gas-engine plant is unquestionably higher
than that of either a steam-turbine or a
steam-engine installation, but the cost
of fuel is considerably lower for the gas
engine; therefore,- the total operating

July 4, 1911

P O W E R

21

cost, including fixed charges, compares
very favorably with steam turbines and
engines.

In the matter of gas cleaning we are
far ahead of European practice. In gas-
engine plants operated in connection with
steel companies in this country-, there
is no trouble at all with dirt in the gas.
Our engines are not cleaned once a year.
The other day I pulled out a cylinder
head on one of our old Allis-Chalmers
gas-blowing engines and it was abso-
lutely polished like a piece of glass;
the amount of dirt in the cylinder head
and on the piston and in the counter-
bore was not enough to make a handful
and there was almost no carbon to be
seen. The amount of dust in the cleaned
gas is about 0.009 grain per cubic foot.
The cleaning plant will keep the dust
down to 0.01 of a grain under all con-
ditions, and the engine builders do not
require less than 0.02 of a grain.

The cost of installing some gas-power
plants is higher than it ought to be be-
cause the gas-cleaning plants are more
expensive than they need to be. The ex-
planation of this needless expense is that
at first nobody knew much about gas
cleaning and they wanted to be safe,
therefore, they installed more capacity
and more machinery than was necessary.

When the Gary plant was started up,
no provision was made for a proper sup-
ply of ignition current. The ignition
system was supplied from the general
lighting system through a motor-gen-
erator set. This was, of course, a very
careless thing to do, because in case
the power went off, the ignition failed
and all the engines went down. I should
advocate for any gas-power installation
an independent storage battery to sup-
ply ignition current. The utilization of
waste heat from gas engines has made
a great deal of headway in Europe. Tests
made in a plant in Belgium showed that
about 13 per cent, of the power of the
engine can be realized from the waste
heat in the exhaust and the cooling
water by generating low-pressure steam
and using it in turbines.

Although it may be true that with
cheap coal the steam turbine and the
gas engine are about alike in total op-
erating costs, a steel plant needs a great
deal of electric power which it cannot
get in any other way but by using its
gas or burning coal. Any blast-furnace
plant which docs not have to supply
electric power for a steel plant and in
which the gas therefore has no value, is
justified in putting in steam turbines for
blowers, etc. But any large blast-fur-
nace plant connected with a steel plant,
where large amounts of power are
needed, cannot afford to put in any-
thing else but gas-engine blowing and
electric units because of the amount of
power that can be generated from the
gas that is saved, due to the better effi-
ciency of those engines.

By E. Friedlander*

The largest gas engine built today is
entirely too small for a large power sta-
tion. To produce power and sell it, we
shall have to go to larger units, as has
been proved by the New York and Chi-
cago stations, which have put in 20,000-
kilowatt units. The speed of the gas
engine is too low. In the Corliss engine
only the valve gear limits the speed; we
all know that the flywheel, the shaft and
the piston and rods do not limit the
speed. A large engine can be built
strong enough to run at 150 revolutions
per minute so far as the shaft, the fly-
wheel and other main parts are con-
cerned; the difficulty is all in the valve
gear. Now the valve gear of a gas en-
gine runs at only one-half the speed
that it does in a steam engine, so I do
not see why we cannot increase the
speed of the engine.

A very serious point is the class of
labor required for operating the gas en-
gine. It should not be necessary to pro-
vide a better class of labor to operate
these engines than is ordinarily employed
in power stations; that means that all
complicated mechanisms should be
omitted.

A gas engine cannot be overloaded if
it is properly rated. It cannot develop
more than the power represented by a
full charge of mixture and that is the
actual full load of the engine. Over-
load ability is a matter of arbitrary rat-
ing; to get 10 per cent, "overload," the
engine must be rated at 90.91 per cent,
of its real full-load ability. This lack of
overload ability is a serious thing. The
amount of overload capacity in elec-
tric central stations is always taken into
consideration when figuring on the size
of the station's equipment.

There is another point in connection
with overload. Gas engines are ven,-
slow in taking their proportion of a
fluctuating load; they always lag behind
the other prime movers, especially tur-
bines. This is probably caused by hav-
ing to take in a charge, compress it and
explode it; the effect of the governor
movement cannot be immediate. Because
of this sluggish response to load changes
it is advisable to install some turbines in
any large alternating-current station
driven by gas engines and supplying a
lot of induction motors.

In our district more shutdowns and
delays are chargeable to faulty cooling
than to any other cause. This is due
more to local conditions than to en-
gine construction. The cooling water is
gritty and contains free sulphuric acid
and iron sulphate, which will attack any
metal, especially steel forgings and pip-
ing. For handling such water, all forg-
ings, such as exhaust valves and stems,
and piston rods, should be lined with
nnncorrosivc material and the piping

made of brass or copper except in the
large sizes; cast iron will do for those.

Ignition has given very little cause
for complaint. The mechanical make-
and-break igniter with forged steel con-
tact points requires the least attention
and is far ahead of the electromag-
netically operated igniter. Each igniter
should be wired up independent of the
others, with its own fuse of four times
the normal current capacity.

The lubrication of gas-engine cylinders
has not been generally satisfactory. The
manner of admitting the oil into the cyl-
inder is just as important as the quality
and quantity of oil used. The oil must
be spread over the surface of the cylin-
der wall and this is preferably accom-
plished by pumping it in with the mix-
ture or as soon as possible after the
scavenging of the cylinder, spreading it
during the compression stroke and leav-
ing the cylinder lubricated for the po>ver
stroke. Oil should never be admitted
during the power stroke and it should
not drop on the piston as soon as it en-
ters the cylinder but should have time to
run down the wall on each side before
it is spread by the piston rings. We
have found it satisfactory to provide two
holes in the top half of each end of the
cylinder barrel, about 40 to 60 degrees
apart; this location does not permit the
oil to drop off to the bottom of the cyl-
inder nor does it leave a dry spot on
the top of the wall between the oil holes.
This method has been used on our en-
gines for the past three years.

By Prof. Charles L. W. Trinks*

It is possible to push the gas engine
up to the highest notch of economy by
designing it for minimum .friction and
throttling losses — using a long stroke
and slow rotative speed. Such an en-
gine, however, would be prohibitive in
price. The slow-speed blast-furnace gas
engine has 2', times the efficiency of a
steam engine or turbine and it would be
better to sacrifice some of this and re-
duce the cost of construction about 25
per cent.

The advantages of increasing the rota-
tive speed are very great; the horse-
power of the engine is increased almost
without additional cost and the first cost
of the electric generator is reduced. With
alternating-current generators, the num-
ber of field-magnet poles would be re-
duced and parallel operation thereby
made easier.

It may be supposed that higher speeds
will decrease the economy without in-
creasing the power very much because
the cylinder will not take in a full charge
of mixture. Examination of a curve
showing the relation between brake
horsepower and average pressure in the
cylinder during the suction stroke will
correct this impression.

•.•^iifHTlntTKlrnt, plfftrlrnl ilppnrttnpnl : K<1- •I'rofi-

gHr Thnm|i«..n SIppI Worka.

if fnorlinnlrnl

npglp Tirtinlml MrliooU. ritl<<liiire

"■rlnit. Pnr-

22

POWER

July 4, 1911

Engineering in the Oilfields

Some years ago, while employed in
the field by a large oil company, I set
up a locomotive type of boiler which
was to be used to steam oil. It carried
a steam pressure of 60 pounds. After
connecting the ball-and-lever safety
valve it was my intention to lead the dis-
charge outside of the boiler room, but
my shift ended before this connection
was made. The boiler was fired up that
night, and the next day when about to
put a nipple in the safety valve I found
a plug screwed into the opening. I was
told that the valve blew off and filled the
boiler room full of steam.

A few days later I saw something
hanging from the crown sheet of the
boiler where the fusible plug should
have been. I found a piece of -^i-inch
pipe, welded at one end, screwed into
the hole intended for the fusible plug;
the fusible plug had burned out. I
removed the gas-pipe plug and put in
a fusible plug, and later on got another
job.

B. F. Hartley.

Tipton, Cal.

Oil Drip Pans

I recently visited several e.igine rooms
and noted that oil-soaked floors and
numerous oil pans were features which
did much to mar the otherwise neat ap-
pearance of nearly every plant I saw.

One floor was so saturated with oil
that an attempt to walk across it was
hazardous. The others invited improve-
ment.

Oil pans surrounding an engine are an
eyesore, although in most cases a few
are necessary.

I have succeeded in reducing the num-
ber of drip pans in my plant from six
to three, and hope to dispense with one
of these soon.

An oil guard, made of sheet iron,
painted the color of the engine, and encir-
cling the eccentrics for nearly one-half
their circumference, took the place of
two pans. The guard is secured to the
pedestal of the main bearing by brackets
and has two slots through which the ec-
centric rods pass. The oil is carried
away through a small pipe.

The pan that caught the drip from the
governor was exchanged for a small
sheet of iron, fastened out of sight under-
neath the engine frame.

I believe that grease cups are the
best thing out for crosshead pins.

Grease is suitable in some cases for
crank-pin lubrication, but I would hesitate
about changing where a good centrifugal
oiler was in use.

It was once the practice to lubricate
bearings just enough to run them with-
out excessive heating and the oil then
used was allowed to go to waste. Now
it is more economical to use a liberal
amount of oil which can be saved and
used again many times.

L. W. Roy.

Ware, Mass.

Has Poor Draft

The accompanying illustration shows
how the smoke connections are made to
my three boilers. For some reason the
draft in the furnaces is not as strong
as I think it should be and I would like
some reader to point out the fault.

The boilers are each 72 inches in diam-
eter, 16 feet in length and contain

Diagram of Smoke Connections

seventy 4-inch tubes. The distance be-
tween the back wall and the end of boiler
is 15 inches, that between the flue doors
and front head is 17 inches. The con-
nection between the smoke flue is 10
inches by 67 inches. The header is
round and is 34 inches in diameter over
the first boiler, 44 inches over the sec-
ond and 52 inches over the third, and
continues in this size until it reaches
the stack, which is placed 12 feet from
the last boiler.

The stack is 54 inches in diameter and
is SO feet high above the grates. The
herring-bone grate bars contain 33
square feet. I use a very slow-burning,
dry, bituminous coal and am compelled

to carry a thick fuel bed. For that rea-
son I need better draft than I now have.
How can it be improved?

L. P. Cotton.

Lawton, Okla.

Drawing on a Crank Disk

At a cold-storage warehouse I had to
remove a loose crank disk from a pair
of engines. A ram and supports were
rigged up, and the largest bolts avail-
able were 2'^ inches in diameter. I had
no trouble in removing the old disk, but
the builders gave us about 0.007 to draw
over the shaft on the new disk, and the
threads were sheared entirely off the
bolts before the disk had been forced
on one inch. I next borrowed some 4-
inch bolts 60 inches long, and managed
to draw the disk into place.

In allowing the disk to stand still while
I took up the nuts to avoid changing the
jack and get more leverage, I was afraid
I could not start it again, but the engine
operated nicely and g-ve no further
trouble.

The manager of the company said he
was positive we had made a mistake in
boring the hole for the crank shaft in
the disk as he had measured it and knew
it was much too small.

D. L. Fagn'an.

New York City.

Isolated Plant Held Its Own

I have read many articles of how the
engineer should lend a helping hand to
his brothers and, by helping others,
help himself. I have wondered who
among the engineering profession is in a
position better qualified to show the
brother engineer in the isolated plant
where his mistakes and wastes are
(if he cannot see them himself), than
the central-station man. But he profits
by the isolated-plant engineer's ignorance
or neglect. He gets what data he can
on an isolated plant and then will go to
the isolated-plant owner with a bunch
of figures telling him that he can furnish
heat, power and light so much cheaper
than his engineer is doing. The central-
station engineer's job depends on all the
business he can control, and the bigger
the works the bigger the pay. One in-
stance where a central-station man un-
successfully attempted ousting an iso-
lated-plant engineer is worth mentioning.
The central-station company got permis-
sion to run a test to show the isolated-
plant manager where he was losing

July 4, 1911

POWER

23

through his steam plant and how it would
pay to install central-station power.

The isolated-plant engineer was a man
of brains, and when the men from the
central plant began the test, he deter-
mined to assist in every way he could.

After running the test it was found
that the isolated man had the best of the
situation.

B. P. Pace.

Keshena, Wis.

Misplaced Injector Suction
Pipe

An engineer bought a 2-inch injector
coupled up in the usual way, the lift of
which was about 6 feet. He was unable,
however, to get it to work and I was
called in to look it over.

I found that the suction pipe of the
injector ran to a hotwell in which a 's-
Inch copper drip pipe from the pump
steam chest discharged at the inlet of
the injector suction. Steam bubbles
were given off which destroyed the in-
jector vacuum, thus preventing its work-
ing.

I changed the suction pipe of the in-
jector to the other side of the hotwell,
which removed the trouble.

H. Potter.

Montreal, Can.

Gasket Punch

A pocket knife is generally used when
cutting holes in rubber or leather gas-
kets. This method produces poor results.

In order to get good holes quickly,
take a pipe nipple of proper size and
grind it to a cutting edge. As there are
about as many pipe sizes as bolt sizes,
there is nn difficulty in making any size
of punch.

F. U'. Bentley, Jr.

Huron, S. D.

Expen.sive Kconouij'
A certain power plant was installed a
few years ago and, with few exceptions,
the equipment was of the best and was
carefully erected.

The roof of the engine room, however,
was made of 2-inch planking, supported
by steel truss beams. The planking was
covered with tar paper and gravel. The
exhaust pipe extended up through the
roof and supported a type of exhaust
head which threw the oil and water all
over the roof. This soon so softened the
paper that when it rained the engines got
the benefit. A rough shelter had been
built over the dynamo to protect it from
the wet, and the only dry place in the
plant was at the switchboard, the part
of the roof over it being nut of reach of
the exhaust head. As if to remedy this
the blowoff from the oil separator was
piped to a barrel set on the roof directly
over the switchboard. The action of the
SUP on the barrel sron caused this sec-
tion of the roof to leak as badly as any

other part. A cover was erected over the
switchboard and the engineer could,
while standing in a puddle of water,
reach in and operate the switches, etc.

When the float in the open heater wore
out, a square one was made out of sheet
iron, this being considered cheaper than
a round one of copper. This lasted about
three days before it collapsed. Three
others were tried and lasted about the
same length of time. When the last one
collapsed the attendant was busy else-
where. The power engine was flooded,
breaking the main bearing and damaging
the armature winding. The accident
caused a shutdown of three working
days for 100 men and it cost S85 to patch
things up.

F. Morse.

Edmonton, Can.

Tube Cleaning Kink.

The illustration shows an outline of a
vertical boiler which is operated in this
vicinity. It had not had the flues cleaned
for a long time and a flue cleaner was
ordered. In cleaning, the operator must
stand on the upper drum and feed his
cleaner down. Because the operator
must be confined in the drum, a steam-
driven machine was out of the question.

Cleaning, TObes in Vertical Boher

Water was not available in sufficient
quantities at the required pressure, so an
air machine was used.

The machine arrived and, superin-
tended by the engineer and several others,
the work was commenced. The machine
ran fine, but after several tubes had been
cleaned the dust in the drum became too
much for the fireman doing the job.
Covering all the tubes excepting the one
nn which he was working helped mat-
ters some, but was not sufficient. Stop-
ping them up tight with plugs stopped the
dust all right but unfortunately the draft
also, and the drum of the still warm
boiler became unbearable.

The fireman finally discovered a remedy
himself. He took a small hose into the
drum with him and let a very small
amount of water trickle into the tube on
top of his cleaner. This stopped the
trouble completely and as far as I can
see did no harm to the machine.

John Bailey.

Milwaukee. Wis.

Lubricator Condensing
Chamber

If the reader will examine the sight-
feed lubricator on his pump or engine
he will see a round, polished, hollow
chamber on top of the lubricator. Why
is it there? What does it do? What
is it good for? Is it in the right place?
Lubricator manufacturers will state that
it is a "condensing chamber."

What does it condense? The common
double-connection lubricator feeds oil
into the steam pipe only because the !4-
inch or "i^-inch pipe leading from the
lubricator upward and tapped into the
steam pipe above the instrument is full
of water — condensed steam.

If this pipe is full of water, the so
called condenser is full of water also
and does no condensing. It does act as
a condenser when first put into opera-
tion, but as soon as it becomes full of
water, the ' |-inch pipe does all the con-
densing after that.

No one can give a valid reason why
the so called condensing chamber is lo-
cated where it is; it is simply a matter
of custom, like many other things.

The proper way to connect up a lubri-
cator is to remove this chamber and put
it at the top of the pipe where it can be
a real condensing chamber.

C. H. Wallace.

Racine, Wis.

Obtaining Information from
the Chief

If the young engineer or fireman
shows that he is interested in his work
and will go to the chief, when he is
not too busy, he will generally get the
information he desires.

About two years ago I was with a
chief engineer, in a large steam-electric
power plant, and assisted in lining up a
new high-pressure cylinder on a cross-
compound engine. When the job was
finished I stood by on the night shift
while trying out the new cylinder.

When ready to indicate, the chief sent
for me and explained the details of in-
dicating in such a comprehensive man-
ner that, with my theoretical infomiation
and experience with diagrams taken
from simple slide-valve engines, I could
understand the matter thoroughly.

The chief who gave me the diagram
information was called "big-headed."
"hard-hearted" and "nigger driver"; and
that it was only by the aid of his as-

24

POWER

July 4. 1911

sistants that he could hold a position,
but most of his "stand bys" were either
discharged or resigned and he has been
promoted from chief engineer to super-
intendent of construction of power
plants.

But when the progressive engineer is
promoted his troubles begin. Sometimes
the employees take advantage and make
trouble, and in some cases infer that the
newly promoted engineer is to blame. I
have had this happen to me on two or
three occasions.

William Piper.

Salt Lake City, Utah.

Careless Use of Chain Tongs

The careless use of the chain pipe
tongs is the cause of many permanent
leaks in steam-pipe lines. The accom-
panying illustration shows a common re-
sult caused by the careless placing of
the pipe wrench when putting up the

Leak Caused by Chain Pipe Tongs

work and bending the pipe, as shown
at A. This causes a leak at the joint.

Had the chain tongs been placed in
the position shown in the illustration,
there would have been no leak at the
throttle, even though the chain tongs did
crush the pipe.

C. R. McGahey.

Baltimore, Md.

Drill for Brickwork

An easy means of drilling holes through
a brick wall is to take a piece of gas
pipe the desired length and cut a saw-
tooth edge on the end. It is then put in
the fire and flared out enough for clear-
ance.

Next take a piece of light cast iron and
bring it to the melting point, and, having
the pipe as hot as possible without dan-
ger of burning, hold it in the molten
metal and cover the end with a thin layer
of cast iron. Then dip it in cold water.
With a little practice one can make a
first-class pipe drill that will stand a
lot of abuse.

Frkd W. Smith.

Dixon, 111.

Plugged Blowoff Pipe

The blowoff pipe of a boiler became
plugged. The difficulty was overcome
by attaching a strong hose to the feed-
pump discharged pipe and to the end of
the blowoff' pipe. Then the blowoff valve
was opened and the feed pump started
for a few seconds with the feed valves
closed. When the hose was disconnected
the pipe was found to have been freed
from its obstruction; thus a shutdown
was avoided.

Roy W. Lyman.

Ware, Mass.

Engine Safety Stop

The accompanying illustration shows
a safety device I made and used suc-
cessfully on an engine with no means of
stopping automatically should the gov-
ernor belt break.

This simple device when not in service
is shown at /I ; it leans just enough to the
left to prevent its falling over to the po-
sition shown by the dotted line. The
knockoff-bell crank E has a pin C in the
top, with the end turned to come against
the upright rod when the ball A is on
top. As the bell crank moves down,
the pin C will force the lever and ball
slightly forward, when it will fall in the
position shown by the dotted lines; the
arm H bearing against the catch-block

-V

Hetails of Safety Stop

arm keeps the latter from hooking on and
lifting the valve.

The bell crank £ travels up and down
as the governor rises and falls and a
pin in the end of £ bears against the
tail of the catch-block arm and, forcing
in the lower end, trips the valve. When
the governor belt breaks, the governor
moves the bottom of the bell crank £

toward the cylinder, but the part with
the pin C travels away from the cylin-
der. The pin coming against the up-
right rod tips it over to the position
shown by the dotted lines. The shaft F,
on which is attached a similar lever at
the crank end, extends to the opposite
end of the cylinder.

A. C. Waldron.
Revere, Alass.

Makeshift Pulley Lathe

Some years ago in a little shop which
built machinery and did repair work, a
job would frequently come in that would
require some queer manoeuvering.
B

How THE Pulley Was Turned

One day it was necessary to turn sev-
eral large wooden sheaves. As no lathe
in the shop could turn sheaves over 3
feet in diameter, the job was done as
follows: Two ordinary carpenters' horses
were procured upon which were bolted
the bearings B B. The sheave C was
mounted on a short shaft D, which was
then placed in the bearings.

The pulley £ was put on the shaft on
the outside of one bearing. The two
horses were placed close together so as
to bring the pulley £ in line with the
pulley F, which happened to be a small
pulley on the end of the engine shaft.
After securing the horses to the floor
the belt was put on the pulley and a
piece of wood nailed across from one to
the other, as at H, to which a piece of
iron was fastened for a tool rest. After
slowing the engine down to a suitable
speed and using a heavy hand gage over
the tool rest H the groove in the sheave
was turned out as well as could be done
anywhere.

George J. Little.

Passaic. N. J.

Broken Flange Repaired

An engineer, in tightening up the nuts
on a flange joint, broke out a part of
the flange.

In making the repair it was decided
to shrink a ring on around the flange.
The ring was made out of a Sj-inch
square iron bar and bedded down to the
flange, being drawn slightly to allow for
shrinkage. The ring was then heated and
forced on, the broken part of the flange
being kept in place by a pair of tongs
gripping a stud that was in a bolt hole.
John S. Leese.

Manchester, Eng.

July 4, 1911

POWER

25

Vacuum Increased bj' Re-
ducing Pump Speed

In the April 25 issue, C. D. Eldredge
cites an instance where he increased the
vacuum in a condenser from 26' _. to 28' _-
inches merely by reducing the speed of
the rotary pump from 72 to 44 revolu-
tions per minute. While at first glance
this may seem very problematical, his
conditions may be such that, if they were
known, the reasons for this rather start-
ling result would be quite simple. For
instance, it is possible that he was put-
ting a great deal of entrained air with
the water into the condenser, which would
militate greatly against a good vacuum,
or it may be that the discharge from the
pump was either throttled or too small,
so that he really did not get the quan-
tity of water he supposed with the pump
running at 72 revolutions per minute.
There are other possibilities in connec-
tion with the case that might explain
it. It would prove of interest to hear
further from Mr. Eldredge in the way
of a brief description of his condensing
plant, giving the type of condenser,
amount of water pumped, steam con-
densed, etc.

EvERARD Brown.

Pittsburg, Penn.

Inspectors Disagree
Joseph King, on page 846 of the May
30 issue, seems much disturbed over
the nonagreement of the State and insur-
ance inspectors over examining a certain
boiler of the original Manning design;
and he infers that as the State inspector
had ordered the most extensive repairs,
he should be credited with the best in-
spection. In the first place, it should be
understood that there can be no real con-
troversy between the State inspectors and
the insurance inspectors in the State of
Massachusetts, for the insurance in-
spectors are all examined and issued
certificates of competency by the State
authorities before being permitted to do
inspection work in the State; they are
therefore practically State representatives
in the performance of their duties. Any
conflict in opinions between inspectors in
Massachusetts is merely individual dif-
ference of opinion. The department is
excellently administered by its chief in-
spector, who sees to if that the opinion
of the individual does not interfere with
obtaining safe and practical results
through the inspection service.
Mr. King is evidently unfamiliar with

the subject of boiler repairs, or he would
not criticize the variations in these in-
spections in favor of the State inspector's
report as he gives it. Putting in a new
set of tubes and a new door ring for
a boiler of the type described would be
prohibitive for a boiler 21 years old;
such repairs would cost about as much
as a new boiler. The type of door ring
referred to is the same as illustrated in

Boiler Leg Ring

Door Ring Welded to Leg Ring of
Boiler

the sketch, the U-shaped door ring be-
ing welded to the leg ring of the boiler;
the section of the leg ring across the
bottom of the door serves only to pre-
vent distortion of the furnace sheets ad-
jacent to the door opening, the action
being similar to that in the spring of a
steam gage. If this portion of the leg
ring is damaged and can be stiffened by
patching, as called for by the insurance
inspector, such repair is all that can be
required for safety. It is, of course,
folly for anyone, without seeing the
boiler, to say whether it was necessary
to remove 10 tubes or the whole set to
make this boiler safe for further opera-
tion. In making an inspection it is, of
course, much simpler to say remove all
the tubes than it is to select a certain 10
tubes for removal and let the balance
remain in service, and this without fur-
ther evidence in the matter would lead
me to believe that the insurance in-
spector had made the more careful ex-
amination of the two. The matter of
whether one or two patches should be
required a* the sides of the fire door Is
probably not of serious moment, as such
patches were probably required to re-

move fire-cracked portions of the origi-
nal furnace sheet and to stop leakage,
and their application had very little bear-
ing on the immediate future safety of
the boiler. It would seem that Mr. King
is trying to make a mountain out of a
molehill and in doing so is allowing his
zeal to run away with his better judg-
ment.

J. E. Ter.man.
New Haven, Conn.

Coal Defined
Referring to the article headed "Coal
Defined," in the May 30 number of
Power, I would suggest that both gentle-
men stick to the Century dictionary or
some other modern dictionary and leave
out any such confusing term as "pure
coal." Why not arrange Mr. Bement's
Table 2 as follows:

Proximate Composition of Coal

Coal = Dr.v Coal + Water.

Dry Coal - Coal — Water = Combustible Ele-
ments ~r Noncombiislible Elements.

rnmhiistihir Kli'ini'iits — Volatile and Nonvol-
alili' c.nilHistil.le Elements.

Ni>n(<,nil.iislilili' Elements = Ash + Volatile
NoiiiMinlnisiilile Elemenls.

.\sh - .\ny Siilids Kemainin!; after Complete

Vuliililr' Noncombnslllile Elements =r Those
Vcilniilrs IMiven Off during Combnslion
wiiliiHii Cheniiral Change.

Ciinl Nimv.ilntile Comlmstlhle Elements +
V(il:\iilc> ('.irnlmslihle Elements + Volatile
Nniiicinliusiihle Elemenls + Ash f Water.

John Clarke Watson.

Joliet. II

Power Plant Betterment
Referring to the paper presented to
the congress of technology by H. H.
Hunt at Boston on April II and published
in the May 2 issue of Power, in the sec-
ond paragraph Mr. Hunt states that a
casual inspection of a small plant will
often reveal a more or less heterogeneous
collection of apparatus and machinery,
some of which dates back to an early
date. This, he declares, together with
the fact that such a plant is usually op-
erated by a force of engineers and fire-
men of only ordinary intelligence and
ability, might naturally lead to the con-
clusion that, even under the most favor-
able conditions, high power cost is to
he expected. It is my opinion that if Mr.
Hunt will go into some of these plants
he will be surprised to find that they
are not run so badly or operated by such
an ignorant force as he attempts to
make us believe and that the economy
and service are not so far behind that of
the more modern station of the same
size. Is it not because things arc well
run and taken care of that the manage*

26

POWER

July 4, 1911

ment hesitates to throw out the old equip-
ment and put in newT-*

As to the men being of only ordinary
intelligence and ability I think his re-
marks are not well founded. Many of
the engineers in these "antiquated" sta-
tions are studying modern engineering
methods, and are getting as much out
of their plants as it is possible to get in
order to make a good showing in com-
parison with the more modern plants.
Another thing to be said for these men
is that they usually have more difficulties
to meet and repairs to make than do
the engineers in the more modern plants.
I question very much whether there are
many of the experts Mr. Hunt refers
to who could give these engineers many
especially valuable pointers. It certainly
does not require an expert to point out
that there are leaky flues, incorrect gages
or dirty boilers, and I do not believe Mr.
Hunt will find many plants where such
conditions exist or would be allowed to
exist by a management which is pro-
gressive enough to look into such things
and consider calling in an expert. I think
that the management would first get rid
of the slack engineer and get a com-
petent one, and when this had been done
there would not be any need of the ex-
pert.

As to engine valves, most engineers
possess an indicator and know how to
use it. I do not believe that there are
many engineers, even in old plants, who
need to be taught how to set the valves
of their engines.

In one place Mr. Hunt says that the
station should be thoroughly cleaned — as
though the average engineer has not self-
respect or brains enough to keep his sta-
tion clean.

As to maintaining a steady steam pres-
sure, I want to state right here that I
can produce some steam-line diagrams
that almost conform to a true circle and
my plant is of the kind to which he re-
fers, excepting the condition.

Mr. Hunt assumes that the engineers
understand how to start and stop their
engines but leaves us to infer that the
expert would have to let them know when
the light- and heavy-load periods came
on so that they would know when to
change over.

As to checking up the coal, I am
afraid that he will have to do some hunt-
ing for plants in which they are not
keeping close records of the coal con-
sumption, output, cost per kilowatt, etc.
The average chief engineer can usually
run evaporation tests to determine the
best fuel to be used, and the best meth-
ods of firing it. Here, again, it is
hard to see why an expert should be
called in to do this and to advise the in-
stallation of a CO; recorder when the
fee saved would almost pay for one.

Mr. Hunt goes on to show that after
all the expert does and suggests, the
economy of the plant is liable to de-

crease and that an expert should be
called in periodically to check things
up. In other words, I infer from what
he says regarding the upward tendency
of wages that in his opinion power-plant
owners should get cheap engineers and
then have the expert come around oc-
casionally and fix things up. I am happy
to say that I do not believe that there
is a very large field for this kind of ex-
pert, as the average present-day power-
plant owner usually gets an uptodate en-
gineer who will keep his plant in first-
class condition at all times.

W. F. Cox.
Vicksburg, Miss.

Rolling Boiler Tubes

Letters have appeared in the columns
of Power from time to time concerning
the proper way in which to roll boiler
tubes so as to make them tight and at
the same time avoid cutting them on the
edges of the tube sheet at the point
where they pass through it.

I believe that a good rule to follow
in doing this is to set out the expander
gradually and continue rolling until the
tube feels smooth to the touch inside, op-
posite to where it bears against the sheet.
This will make a tight tube and there will
be little danger of cutting if the rolling
process is stopped when this point is
reached.

On examining the ends of old tubes
they are frequently found to be cut al-
most through at some points in their cir-
cumference. This is done in most cases
by the mandrel of the expander having
been driven too hard and not turned
enough before the rollers were again set
out.

S. KlRLIN.

New York City.

High Pressure Drips

Victor Bonn in the .May 23 issue has
misquoted my letter of April 11. If he
will read it carefully he will see his
mistake. He states that he never ran
across such an arrangement as to drain
high-pressure condensation into the low-
pressure receiver. I stated in my letter
that the condensation from the high-
pressure discharge was connected into
a pipe that drained the condensation of
the working steam in the receiver to a
trap. The pipe that drains the receiver
of condensation to the trap performs the
same function as a vapor pipe.

Mr. Bonn says there are a number of
high-pressure traps where he is em-
ployed and he finds that the drip-return
pipes are quite cold a short distance
from the trap. I will agree with him
on that statement, for at the plant where
I am employed we have a number of
traps that are the same, but they have
not much work to perform. We have
others located from 50 to 100 feet from

the hotwell where they discharge, and
the return pipe at the hotwell is so hot
that a hand cannot be held on them.
These traps are in good working condi-
tion.

Some time ago at this plant a new
hotwell tank was installed at a different
place from the old one. The drip re-
turns from all steam traps were dis-
charged into the hotwell above the water
line. There was so much liberated steam
from the returns that the water in the
hotwell could not be seen and in the
room where it was located it made the
atmosphere hot and suffocating. To
overcome this difficulty, the discharge
from the drip returns was extended
below the water line. The vapor from
the drip returns is now condensed by
the water in the hotwell.

From my experience and observation
with high-pressure drips, I think Mr.
Meinzer was justified in making the
change.

R. E. Enicne.

Kansas City, Mo.

Constant Receiver Pressure

1 would like to ask Mr. Johnson, who
writes on constant receiver pressure in
the May 16 issue, if he ever ran a com-
pound engine carrying the following
loads: A street railway, a number of
dock-unloading machines, bridge cranes
and ore and coal car unloaders; or a
rolling-mil! engine direct connected to a
three-high ruffing roll, where one instant
the full load is on and the next instant is
off.

If Mr. Johnson ever had to get regula-
tion on an engine running under the
above conditions, he would readily see
the necessity of a constant receiver pres-
sure and avoid a larger hole in his coal
pile.

Again, what has the receiver pressure
got to do with the governor revolving
in its highest plane? If he calls it engi-
neering to have one cylinder doing more
work than the other, perhaps he will ex-
plain where he gets his economy. He
says that the engineer's problem is to
keep the wheels turning with as little
coal consumption as possible; and it
goes without saying that with the short-
est cutoff in the high-pressure cylinder
the steam consumption will be least. Mr.
Johnson says nothing about regulation.
Whether he has to maintain a 2 or a 10
per cent, regulation each side of normal.
If he will stop to consider, he will readily
see that with a constant receiver pres-
sure, and with the cutoff so adjusted as
to equally balance the load ; the low pres-
sure will at all times be doing its share
of the work and the high-pressure cylin-
der has less to do, and it will cut off
earlier in the stroke.

W. R. BE.4RD.

Cleveland, O.

July 4, 1911

POWER

The Screw Pump

In the May 30 issue of Power, George
H. Thomas has asked for further in-
formation regarding the screw pump. In
this plant, where I have been in charge
for over five years, our pumping in-
stallation consists of three screw pumps,
four duplex steam pumps, one single
steam pump, two triplex pumps and two
multiple-stage turbine centrifugal pumps.
Of this collection of pumping machin-
ery I have become extremely partial to
the screw pumps, as they have required
very little attention and have given un-
usually good and constant service since
their installation. By referring to the
cut, the reader will see that the only
packing necessary is at the points
A and B on the outer ends of the shafts.
The packing is applied on the suc-
tion side only, and does not have to
withstand the high pressure of the dis-
charge, the screws themselves obviating
the necessity of packing on the high-
pressure side.

As the only service of the packing is
to seal up the suction end of the pump,
it is put in very loosely. And from per-
sonal experience the writer has found
that the packing can be done while the
pump is in operation by reducing the
suction until the weight on the suction
chamber is equal to the atmospheric
pressure. Four or five hours of time

We had an interesting experience at
one time. The suction had become partly
clogged up and one packing-gland seat
had become worn so that the suction
pulled the packing into the pump and
drew in so much air that it was neces-
sary to leave a J^J-inch pet cock open
on the top of the elevator pressure tank
the balance of the day to keep the tank
from accumulating too much air.

This type of pump is oiled by the ring-
oiling system and requires the same at-
tention that an electric motor does. It
is our custom to fill the reservoirs each
morning, which is sufficient for the day.
The gears are run in an oil bath.

Another feature the writer appreciates
in the screw pump is that the packing
does not in any way affect its effi-
ciency. If the packing leaks a little, it
means only a loss of water before the
work is applied to it, while with the
plunger pump leaking of the packing is
a loss of work. If submerged, the screw
pump would need no packing at all.
L. M. Johnson.

Glenfield, Penn.

In the May 30 issue of Power I
noticed inquiries by George H. Thomas
on page 849, relative to screw pumps.
I know of a plant in which there is a
screw pump used for a plunger elevator,
and upon inquiry learned the following:

Longitudinal Section through Screw Pump

and about three or four pounds of H-
inch packing per year have been found
(o be all that is necessary to pack one
of the pumps, handling between 600 and
800 gallons of water per minute for
twelve hours a day and six days a week.
The pumps require repacking about
once in from four to six months with an
addition of a ring or two about once in
six weeks to two months.

If the packing in a screw pump is
pulled up too tight, it will show signs
of healing before any frictional load can
be detected on the ammeter.

When the pump is lifting water the
duty of the packing is to keep the suc-
tion from drawing air through the pack-
ing glands instead of stopping water
from leaking.

This pump must be shut down while
being packed, but it requires very little
time to complete the job and so there
is no need of waiting for a Sunday to
pack it. It is about two years since this
pump was packed and the p.icking shows
no sign of giving out. Of course, a good
quality of packing was used and the ex-
pense is small. No trouble is had in
keeping the packing tight, and there is
no undue friction of the parts. Con-
cerning the lubrication. I would say that
the cups and receptacles are filled once
every week, and excepting the general
attention that is given everything in the
plant at all times, no special care is
given this pump.

Charles J. Mason.

Scranlon, Penn.

Sulphur for Hot Bearings

I could never see anything in the use
of sulphur for hot bearings. I have
seen it tried and also have tested it my-
self with no good results. A bearing
can always be cooled by the use of me-
chanical skill with the file and scraper.
There are times, of course, w-hen it is
necessary to keep running. I think that
Mr. McDermid's suggestion of brine
cooling is good. I have cooled bearings
with castile soap and salt as well. There
are cases where a fine powder, such as
Bon Ami, will help, but lots of good oil
should be used, as it will be found that
the grains will grind into the metal and
generate heat. It should never be used
on a babbitt bearing, but on bronze and
steel will do good work.

C. R. McGahey.

Baltimore, Md.

Mr. McDermid's experience with sul-
phur in a hot bearing, described in the
May 30 issue, is enlightening and would
seem to eliminate that material from
the list of useful articles for that pur-
pose. However, it is possible that this
material may have been used by others
more successfully in a different manner,
and a further discussion of this and
other methods by the engineers would
perhaps be of interest to many.

I have heard of a variety of things
that are good for hot bearings, such as
soap, soapstone, sapolio, rotten-stone,
sulphur water, molasses, white lead, cas-
tor oil and white lead and graphite.

Of these I have personally tested
graphite and, while it is a good lubricant
under some circumstances, it appears,
when mixed with oil and poured into a
hot bearing to form a sort of dry coat-
ing or gum upon the bearing surfaces,
and perhaps for that reason does not
cool the bearing as rapidly as other
methods.

Castor oil is very good where the op-
erator has discovered the hot bearing
before smoking occurs.

The most successful way I have found
to cool an excessively hot bearing is
to connect a hose and allow a small
stream of clear, cool water to flow
through it, using no other lubricant for
the time being. Water containing sand
or mud should not be used. Ice or snow
packed around the bearing will material-
ly assist in the cooling process.

After the temperature has been re-
duced to the point of safety a mixture
of white lead and cylinder oil, say a
pound of lead to a quart of oil. can be
poured in a little at a time and good
results will almost invariably follow.

Water used in a bearing wnII make a
rough surface on the wearing parts
while the white lead, being very mildly
abrasive, will tend to smooth and polish.
The two treatments combined as above
arc analocmis to the method of oricinal-

28

POWER

July 4, 1911

ly finishing tlie shaft or pin in the lathe
by using first coarse abrasives and then
finer.

Where it is impracticable or unsafe
to use water, on electrical machinery, for
instance, large quantities of ice-cooled
oil poured in and allowed to run out of
the reservoir generally gives good re-
sults.

In those journals having a large oil
box in the cap, untried tallow may be
packed in a manner not to intefere with
the regular lubricating arrangements. If
the journal heats, the tallow will melt
and save the box frequently and the op-
erator will in all probability smell the
heated tallow in time to save trouble.

I have heard of a grease made of white
lead being used by some engineers and
graphite in cases of chronic heating, and
I would be interested to hear of some
personal experiences with this method.
F. C, Holly.

Yazoo City, Miss.

I read with much interest in the May
30 issue of Power, page 849, H. B. Mc-
Dermid's letter on "Sulphur for Hot
Bearings."

Some time ago we had trouble in our
mill with a hot box on one of the main
line shafts, carrying a rope drive and
transmitting 400 horsepower with a side
pull. The shaft is 5 inches in diameter
and perfectly in line and level. It ran
so hot that we kept a man tending it
for more than a week, and alternated
with water and oil to keep the mill run-
ning. Between runs we tried the Sapolio
and oil remedy, as well as everything we
could think of or ever heard of (except
the sulphur remedy), with no etfect
whatever.

The master mechanic had a new- and
longer box made and put in the hanger,
hoping that the increased bearing sur-
face would help it, but it ran just as
hot as it did before.

The next morning the master mechanic
got up on the staging and watched the
bearing as it worked and noticed that
the oil seemed to come out of the end
of the bearing at the point of contact
which was about one inch above the
joint between the bearing and the cap
of the box. This led him to believe that
the oil was not being properly distributed
over the bearing surface.

That evening he ordered the box taken
down, and with No. 1 sandpaper he went
over that part of the shaft inclosed by
the bearing lengthwise. The shaft was
then wiped clean, the box put back and
the oil chamber filled with oil (for this
was a ring-oiling box).

The next morning we started up. The
man was at his post to nurse that hot
box, but it did not get hot. The bear-
ing has given perfect satisfaction ever
since.

James Mitchell.

North Adams, Mass.

Central Station versus Isolated
Plant

The discussion of the subject "Central
Station versus Isolated Plant," which has
been running in Power for some time,
interested me very much as the central-
station people have made a bid to take
over the plant in which I am employed.
Our plant consists of one 150-horse-
power Corliss engine, one 40-kilowatt
direct-connected high-speed engine and
generator, one large steam pump and
several small pumps.

We use practically all of the exhaust
steam for heating and manufacturing,
aboi;t six months of the year, and from
30 to 40 per cent, during the balance of
the year.

The Corliss engine carries a fairly con-
stant load of from 125 to 150 horsepower,
winter and summer. The high-speed set
has a load of about 15 kilowatts through
the summer months and about 40 kilo-
watts in the winter.

The central-station man looked over
our plant and made inquiries about the
amount of steam used for heating and
other purposes aside from that used for
power alone. Finding that our engines
were acting as reducing valves between
the boilers and the heating system for
the greater part of the time, the power
being obtained as a byproduct, as one
might say, he told us that he could not
save us anything by installing motors to
run on central-station current.

I am constantly endeavoring to im-
prove my plant and run it as economical-
ly as conditions will allow. 1 have asked
for a new generator to be run by a belt
connected to the Corliss engine which
is belted to the line shaft.

This will allow the direct-connected set
to be shut down a good part of the time
except in winter and as the Corliss is
considerably more economical than the
high-speed engine we expect to make a
little saving. A 15-kilowatt generator
will handle the day load nicely but to
provide for an increase in the future we
will put in a 20- or 25-kilo\vatt machine.

We are also considering putting in a
large power pump to take the place of
the present steam pump, retaining the
steam machine to use in case of a break-
down.

The addition of the power pump will
give the Corliss a fair load and tend
to improve its economy. In case the
engine becomes overloaded we can start
either or both of the other machines to
relieve it. To furnish steam we have
three horizontal return-tubular boilers
rated at 70 horsepower each. At pres-
ent we are burning from 15 to 16 short
tons of New River coal per week, and
furnish steam for from 160 to 175 horse-
power. The running time is 56 hours
per week. I figure that the steam pump
takes at least three times as much steam
per horsepower-hour as the engine and

charge the steam to it at that rate. We
have four or five motors of from 3 to 10
horsepower each which are used mostly
for overtime work; the high-speed en-
gine comes in handy at such times.

Where steam is used for heating and
manufacturing to such an extent the cen-
tral station cannot compete.

I. P. Elmes.

Lowell, Mass.

It is with considerable interest that I
have followed the letters in Power on
the subject of the relative merits of cen-
tral-station and isolated-plant service.

All of the articles I have read, on
both sides, have treated the matter from
the same viewpoint, that of cost. While
this is, and no doubt will continue to
be, the determining factor, there are
other sides to this question which should
be considered. I wish to say just a word
on the humanitarian and esthetic side.

One who has followed the reports of
boiler explosions will have noticed that
the vast majority are in small plants
while very few occur in large central
stations. Every boiler installed in the
basement of a large building is a menace
to the lives of hundreds of people, and
while a rigid system of boiler inspec-
tion can greatly reduce the danger, the
only way to remove it is to remove the
boilers.

There is an ever grow-ing movement in
all our large cities against the smoke
evil, and this movement will not stop
till it has accomplished its purpose. It
is well known that next to the railroads
the small plants are the worst offenders,
while large stations are comparatively
free from smoke.

An ideal city would be one in which
all light, heat and power w-ould be pro-
duced in one or two large stations. One
plan that has been suggested is to have
all light and power transmitted electrical-
ly, the same station furnishing steam
heat for the business portion, while for
domestic heating and cooking producer
gas could be distributed from one or two
plants.

If the power came from a hydroelec-
tric plant, there would be an entire ab-
sence of smoke and no need for carting
coal and ashes through the streets; a
clean city would be the result. This may
seem visionary, but there are no engi-
neering difficulties in the way; it is en-
tirely a question of cost.

It is my firm conviction that the time
will come when, due to the increasing
cost of coal and the advancements made
in the electrical industry, that even this
difficulty will be removed. While my
vision may never be fully realized. I
believe that it will in a large measure.
Therefore. I want to enter a protest
against making mere money the chief
consideration without taking into con-
sideration other things.

W. Russell Cooper.

Indianspo'.is, Ind.

July 4, 1911

POWER

29

Issued Weekly by tlu?

Hill Publishing Company

John A. Bill, Pres. and Treas, ROB'T McKEAN.S^r'y

505 Pearl Street. New York.

122SoaIh Michigan Boolevani, Chicaso.

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Name and address of correspondent-
Muist be given — not necessarily for pub-
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Pay no money to solicitors or agents
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Subscribers in Great Britain. Europe
and the British Colonies in the Eastern
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to the London Office. Price 21 Shil-
lings.

Entered as second class matter, De-
cember 20, 1910, at the post office at
.New York, New York, under the Act
of March 3, 1879.

Cable address, "Powplb." N. Y.
Business Telegraph Code.

cmrrLATioy sm i:}ik\ t

Of thin i«»iic, 31,000 cHiiicii are piiiitcil.

Xonr unit free reiiulnrhi. no returnx from
ctrfi ronipntlie'^. tlo buck nimihrra. h'ii/urr:i

iiUili

Contents pa

Electrification of Iloosac Tunnel

Burning Gas under Boilers

The Supply of Co.tI

Some Xotc3 on Purchasing Power

Comparative Economy of Saturated and
Supi-rheated Steam

Notes on the Size and Care of Kelts

The Origin of Hydrocarlmns

Notes on Prime Movei's

Saving Effected with Pumping Engine. .. .

Care and Operation of Alternating Current
Dynamos

FlKhIng Line and a Pheasant Cause Trouble

Kilovolt AmpiTcs

Two-phase and Three-phase Allernalors In
I'arallel

Experiences wllb I^rgc Gas Engines In
Sloel Works

Practical I^ein-rs ;

Engineering In the OIKields Oil

Drip I'ans .... Has Poor Draft . . , .
Drawing on a (.'rank Disk. ... Isolated
Plant Held Its Own .Misplaced In-
jector Sucllon I'Ipe. .. .Gasket Punch
.... Expensive Kconomy .... Tube
Cleaning Kink. ... Lubricator Condens-
ing Chamlier. .. .Obtaining Information
from the Chief ... .('.ireless Vse of

Chain Tonu's Drill for P.rlckwork

.... Plugee<) lilownlT Pipe, . . . I'nglne
Safety Stop. ... Makeshift Pulley Ijjthe
....Broken Flange Itejinlrefl I'L'-:

Idsrusslon I.etters :

Vacuum Increased by Ueducing Pump
Speefl. . . .Inspectors Disagree. . . .ConI
Ix-nned .... Power Plant BetliTmcnl

nolllnu' Boiler Tillies IIIkIi

Pressure Drips. .. .Constant Receiver
Pressure. .. .The Screw I'ump. . . . Hub
phur for Hot Bearlnes. .. .Central RIa-
lion versus Isolated Plant 2.":

Editorials 2»-:

Cnefflrlents of Heat Trnnsmlssliin :

Radiators Give Trouble ;

Proht as an Item of Power
Cost

Among the other items which the cen-
tral-station men insist that the owner
who is considering the use of their ser-
vice should include in making up the
cost of his homemade current is profit.

In the price of the proffered central-
station current the profit on the invest-
ment is an item; hence, they argue, it
is only fair that the plant owner should
charge himself with a profit too in mak-
ing up a cost sheet for- comparison with
theirs.

The power user is not interested in
scientific bookkeeping nor advanced
methods of accounting. What he wants
to know is whether he will have spent
more money for power at the end of a
term of years if he puts in or continues
to run his own plant, or if he buys elec-
tricity from the central station.

The simple and obvious way to do this
is to add all of the costs of which he
would be relieved if he subscribed to the
central-station current and see how the
sum compares with what lie would have
to pay the central station. If the cost
of the relief amounts to more than the
relief comes to, he cannot make it an at-
tractive proposition by adding enough to
his own cost to make up the difference
and calling it "profit."

If a man had two hundred thousand
dollars to put into a factory, the steam
plant of which would cost twenty thou-
sand dollars, and if he expected to make
thirty-five or fifty per cent, on his invest-
ment in the factory proper, the question
might arise whether he might not better
put all of the money into manufacturing
and make the larger percentage of the
whole of it than to take oi't twenty thou-
sand dollars for a steam plant which
would make a profit of only, say. twenty
per cent, over what he could buy power
for. But if he did this there would al-
ways exist the possibility of putting
twenty thousand dollars mrre into the
plant and gelling a profit of twenty per
cent, upon it, which is a good deal more
than money costs to loan; so that this
argument applies only to a man who is
at the end of his credit and whose busi-
ness is still capable of extension. And
for him there stand ready a number of
builders of <r.feam plants who are willing
to put in a plant, run it for a term of
years for what the central-station charges

would amount to and then turn it over
to him free and clear, making their pay-
ment out of the difference between the
cost of actually running the plant and
the revenue which would otherwise have
gone to the electric company. If the
above argument were carried out to its
logical conclusion, no electric company
would own its own station for it would
hire a building at a rent that would pay
the real-estate man ten per cent.

The American Gas Engine
It is to be hoped that every American
builder of gas engines will read the full
text of the Pittsburg proceedings of the
Gas Power Section, American Society of
Mechanical Engineers, of which only an
abstract is printed in this issue. The
candid recitals of experiences with large
gas engines are not only interesting and
consoling to those of us whose instinc-
ive faith in the gas engine has hung on
in spite of the antics of both its advo-
cates and their opponents; they con-
stitute evidence of the sort which ought
to give the gas-power industry a strong
impetus in the right direction and re-
newed vigor to follow up that impetus.
Some years ago, in a spirit of absolute
friendliness, we suggested to gas-engine
builders the expediency of admitting and
correcting demonstrated weaknesses and
thoroughly investigating causes of
trouble, instead of arbitrarily assuming
that the gas engine had no defects and
the user was always at fault. The ex-
periences related at Pittsburg amply
confirm our contention that the practice
of gas-engine design was then far from
being perfected, and the results that have
been achieved through the progressive
policy of the large builders in making
good their early mistakes (not by any
means inspired by our utterances),
prove the soundness of our advice —
which, incidentally, brought down upon
us all sorts of criticism, anathema and
even insinuations of ulterior motives,
from gas-power advocates who were too
short-sighted or petty to realize the
justification and sinceritv of our attitude.
However, that is another story. The
main point in sight just now is that the
American gas engine has practically
reached the stage of reliability which
characterizes the high-grade steam en-
gine, but it still costs too much money
and occupies too much space. Get these
factors down to where ihey belong, with-

30

out relinquishing any of the dearly
bought continuity of service, and then

"watch it grow."

Prevention of Power Plant
Accidents

At a recent meeting of the American
Institute of Boiler Inspectors, one of the
speakers said that the members were
active worl<ers in a movement toward
the prevention of industrial accidents. If
the intelligent, well equipped inspector
who has the courage of his convictions
and is unwilling to take a gambler's
chance that a "shaky" boiler will not
fail before the date set for the next in-
spection, always insists that no responsi-
bility for an unwarranted certificate shall
be laid at his door, this is eminently true.
Cooperating with him is the intelligent
and conscientious engineer who at every
opportunity gives his boilers the same
careful examination that is given by the
inspector and also uses his influence to
discourage the use of boilers of inferior
construction.

Until all of the States have taken the
same advanced ground regarding steam-
boiler construction that Massachusetts
and Ohio have, there will be conscience-
less boilermakers who will unload the
poorest possible boilers on ignorant and
penny-wise purchasers. In a great many
cases the engineer is not consulted in
the matter of purchasing power-plant
equipment, and in cases when he is con-
sulted his opinion carries little weight
against the specious argument of the
trained talker whose sole aim is to give
as little real boiler as possible for the
price he gets.

Though restricted in opportunities for
preventing the purchase and installation
of inferior boilers, the engineer can, by
the faithful, intelligent discharge of his
duty in the handling of such boilers, do
much toward the prevention of explosions
and become an honored member of a
nation-wide society for the prevention of
industrial accidents.

The Cornell Economizer

Several of our readers who have suc-
cessfully used the Cornell economizer
or who have known of instances where
its use has resulted in increased capa-
city or improved efficiency, have asked
upon what grounds we condemn it.

We do not and have not condemned it.
Our previous articles were not directed
against the Cornell economizer; we
merely questioned the accuracy of a test
that was reported to have been conducted
on boilers equipped with the device.

There is no doubt that steam can
be decomposed by heat; there is no rea-
son to doubt that the temperature of de-
composition can be attained in retorts
such as are used in the Cornell device.
This point was not questioned in our
editorial. The steam in its passage from

POWER

one retort to another in the series has
its temperature progressively raised and
if enough such retorts are provided,
there is no reason why the temperature
of decomposition should not be reached.
Necessarily in doing so the steam ab-
stracts heat units from the furnace, and
when the resultant mixture is injected
into the furnace and burned back to
water vapor just as many heat units are
released as were absorbed in the process
of decomposition. It is in effect a bor-'
rowing operation in which the decom-
posed gases, like an honest debtor, pay
back the heat units that were required
to insure its creation.

The advantages do not consist of a
gain in heat units in this partictilar part
of the performance but are due to the
injection of the highly heated supply of
oxygen and hydrogen, entraining with it
and heating an abundant supply of air,
increasing the difference between the
ashpit and the furnace pressures and
supplying the requisites of combustion
while maintaining the furnace above the
temperature of ignition, getting in the
air necessary to burn the coal without
reducing the furnace temperature, which
ought to result in rapid and effective
combustion, and explains improvements
which have been made in boiler efficiency
and capacity. It is agreed to install the
system under a guarantee to effect a
given saving and to remove the device
without cost to the customer if it fails
to do so. This is an eminently fair pro-
position and there are doubtless many
boiler plants that can be improved as
much as is claimed by the Cornell Econo-
mizer Company and by the methods
which it employs.

Cost of Furnace Upkeep

In forming a mental estimate of the
cost of steam making, one is apt to con-
fine his attention too closely to the fuel
item and to overlook the cost of upkeep.
With the increasing demands which are
put upon boilers and the high rates of
combustion employed, furnace repairs
and renewals come with increased fre-
quency. The cost of such repairs is by
no means confined to the expenditures for
material and labor in rebuilding the fur-
naces. There is the loss of the use of
the boiler during the time that it is laid
off and the fuss and interruption inci-
dental to the presence of workmen and
material in the plant. Obviously, a great
deal of advantage results from putting
in a furnace which will endure, and we
suggest as a fruitful subject for discus-
sion by our correspondents the best
methods of furnace construction, espe-
cially of those using arches; the best
methods of laying firebrick and the best
sort of material to use. The practice
has arisen of brooming the lining of the
furnace over after it is in place with a
thin wash of fire clay or some refractory
material. One engineer has used the

July 4, 1911

finely ground refuse of the carborundum
furnace for this purpose. Do any of
our readers know anything about the
process and its results? Inasmuch as
a large part of the expense of such re-
newals is in labor, interruption to service,
etc., it would seem to be good engineer-
ing to use high-grade material which
costs no more, perhaps less on account
of its greater regularity, to lay than the
cheaper. In comparing the costs of
cheap and high-grade material the cost
laid should be that which is considered,
and it will usually be found that the
difference in cost between the lowest-
priced brick which can be found and
that of high-class more expensive ma-
terial when that price is reduced to the
cost in the setting will be insignificant
when compared with the longer life and
more satisfactory service which can rea-
sonably be expected from the better
grade.

Information in regard to the method
of failure, frequency and cost of re-
newals, etc., would be appreciated.

The Dignity of Labor
Labor has been variously defined as
exertion of body or mind, as implying
painful or strenuous effort, as an atternpt
to attain useful results. Dignity is the
state of being worthy, having elevation
of mind, superiority and sober judgment.

It is readily seen from the foregoing
definitions that there may be much that
is without dignity in the labor of some
of us, and that occasionally our arroga-
tion of dignity is far from earning its
right to be conjoined to labor.

Labor has dignity only when the work-
man has by skill and common sense so
exerted his mind and his body that he
proves his superiority to the drudge.

In the engineer who has by his sidll
shown economical and efficient results
in the operation of his plant, the dignity
of labor is well exemplified. He is
looked up to and consulted by his owners
and managers; his ideals are high and
he will not stoop to meanness; he is
not overbearing and belligerent; he de-
spises the petty grafter; is quick to
adopt suggestions that will be beneficial
to the managers and add to his own use-
fulness. This engineer is quick to meet
an emergency; he is not a machine that
starts and stops automatically. He is
quick to see the necessity of keeping a
keen eye on his assistants and is ever
ready with cheerful advice.

There is good reason for doubting
whether the dignity of labor is at all
times sustained by engineers who by
well directed efforts could easily w'in
for themselves this much to be desired
quality.

No industry has become great with-
out the aid of the skilled mechanic — this
man of dignity and labor — and his high
development in this country has built up
its commercial supremacy.

July 4, 1911

POWER

Clumping the Frequency of a
Motor

How can an eight-pole 120-cycIe motor
be rewound for 60 cycles? The rotor
is a squirrel cage and there are eight
field coils per phase.

C. W. A.

Rewind the stator with four coils per
phase, to change it to four poles, put-
ting in twice as many turns per coil as
each of the present coils contains. The
rotor need not be changed.

jMcikimir he ivith Compressed
Air

Can you give me some information
regarding the method of making ice with
compressed air? I understand that the
Government is doing it on some of the
war vessels. In the plant of which I
have charge there is a large air com-
pressor, air cylinders 20x12x22 inches.
Having air to spare, we would like to
make our own ice for the shops, say
one ton per day. The compressor runs
in the daytime only. What floor space
would a 1-ton machine occupy, and what
would a 1-ton machine cost?

A. S.

Dense-air refrigerating machines are
used on warships to avoid the danger
of suffocation by leaks from the system.
Th:se machines are very inefficient in
operation and require 10 to 15 times the
horsepower used by an ammonia-com-
pression system. If your company wants
to manufacture about one ton of ice per
day, it would be advisable to purchase
a small ammonia-compression system
plant with an ice-making tank suitable
for this capacity, instead of using the
air compressor which is now on the
premises. The information about the
price and space occupied by such a plant
can easily be obtained from the manu-
facturers of this class of machinery.

Circular muJ Square Juclies

I have a circle 12 inches in diameter
and I wish to find the circular inches.
How shall I do it?

O. K.

To find the area of a circle the square
Of the diameter is multiplied by 0.78.'54.

In comparing the carrying capacity of
wires the electricians have adopted the
practice of expressing the cross-section
In circular mils, which are obtained by
squaring the diameter without multiply-
ing by the 0.7854. The circular inches

in a circle 12 inches in diameter are in
this sense

12 X 12 = 144 circular inches

The actual area of a circle one inch in
diameter is 0.7854 of a square inch.

The number of circular inches in it
is 1.

The area of one circular inch, there-
fore, is 0.7854 of a square inch.

In a circle 12 inches in diameter there
are

12 X 12 >: 0.7854 = 113.1 square inches
and since in one circular inch there is
0.7854 square inch, in 113.1 square
inches there are

ii.yi

= 144 circular inches

0.7854

In reducing the area in square inches
to circular inches 113.1 was divided by
the 0.7854 by which the square of the
diameter was multiplied to get the area
in square inches; that is, the multiplica-
tion is undone. The area of a circle in
circular inches is simply the square of
the diameter, and the object of its use
is to avoid multiplication by 0.7854.

Boiling Water at 32 Degrees

Can water be boiled at 32 degrees
Fahrenheit? If so, how?

B. \l/. D.
Water will boil at 32 degrees in a vac-
uum. If water at 32 degrees is placed
in the bell of an air pump and the air
is exhausted, the water will begin to
boil, and if the vapor is pumped away
as fast as formed, the water will all
boil away in time.

Operating a Dynamo as a Motor

What proportion of its rated armature
current should a direct-current dynamo
be able to carry when operated as a
motor?

If the magnetic field is slightly weak-
ened by inserting resistance in the field
circuit in order to increase the speed,
will that cause the armature to run hot-
ter than otherwise?

C. F. J.

Practically the full rated dynamo cur-
rent. Running as a motor, the speed will
be somewhat lower than when driven
as a dynamo and this will increase the
temperature rise for any given load, but
the difference will be unimportant unless
the machine was right up to the heat
limit when operating as a dynamo.

No.

Length of Steam Ports

What determines the length of the
steam ports of a cylinder?

L. S. P.

Steam ports are made as long as the
diameter of the cylinder will allow.

Motor Losses and Output
A shunt-wound motor at 500 volts
takes 0.9 of an ampere running free.
The resistance of the field winding is
1250 ohms and that of the armature cir-
cuit is 4 ohms. If a load be applied
which makes the total motor current 12.4
amperes, what will be the load and what
will be the efficiency of the motor?

C. H.
The field current is 500 -^ 1250 = 0.4
of an ampere, so that the armature cur-
rent, running free, is 0.5 of an ampere.
The resistance drop in the armature is
0.5 ampere X 4 ohms -- 2 volts, leaving
the remaining 498 volts to be balanced
by the counter e.m.f. The friction and
iron losses, therefore, are 498 volts X
0.5 ampere = 249 watts. These losses
may be assumed to be constant at all
loads, although that is not strictly true.
At a load of 12.4 amperes, 12 amperes
will flow in the armature, because the
field circuit takes 0.4 of an ampere, no
matter what the load may be. The drop
in the armature will be 12 amperes X 4
ohms = 48 volts, so that the counter
e.m.f. will be 452 volts. This, multiplied
by the current, gives the electrical power
expended on outside work and the con-
stant friction and iron losses; the latter
are 249 watts, so that the external work
must be

452 X 12 — 249 - 5175
watts, or 5175 -^ 746 — 6.94, or prac-
tically 7 horsepower. The efficiency is the
net work divided by the total power in-
take. The latter is 12.4 v 5()0 - 6200
watts and the former 5175 watts; the
efficiency, therefore, is

or practically 83;.-^ per cent.

32

POWER

July 4, 1911

Coefficients of Heat Trans-
mission *

By Prof. R. Allen

Heat is lost and conducted from or to
a body in three ways, by radiation, by
conduction and by convection. In most
of the problems in connection with en-
gineering work heat is transmitted by
radiation and convection from a surface;
the loss of heat by radiation for ordinary
differences in temperature depends upon
the difference in temperature of the two
bodies between which there is a transfer
of heat and upon the nature and condi-
tion of the surfaces composing these
bodies. The loss by convection depends
upon the difference in temperature be-
tween the medium passing by the sur-
faces and the temperature of the sur-
faces to and from which the heat is be-
ing conducted, also upon the form of the
body and the velocity of the air passing
the surface. In general it is independ-
ent of the nature of the surface.

In heating work it is very important
to know the heat loss through the various
forms of heating surfaces. These sur-
faces may be divided into two general
classes: those in which the heat passes
from the surface by the natural circula-
tion of the air along the surface pro-
duced by the heated surface itself, and
those in which the air passes by the sur-
face due to a forced circulation, as in a
fan system. In the first class a large
portion of the heat is given off by radia-
tion and in the second it is almost all
given off by convection. Consider first
those surfaces along which the air cir-
culates by natural draft.

Engineers have generally agreed in
this case that the transmission of heat
depends upon the difference in tempera-
ture between the air in the room and the
steam in the radiator multiplied by a
certain constant depending upon the form
and the condition of surface. Experi-
ments upon the transmission of heat
through surfaces have been conducted at
the University of Michigan for about
twenty years, and it has been found that
under similar conditions the coefficient
of transmission for the same radiators
remains constant. The constants are
made known in the following manner:
The condensation of the steam in the
radiator is carefully determined per
square foot of surface and this multi-

•Abstract of paper read before tlie National
District Heating Association, at Pittsburg,
June 6-8.

sion will be affected by the temperature
of the surfaces to which the radiator
emits its heat. In the first experiments

TABLE 2. HEAT TRANSMISSION

THROUGH CAST-IRON RADIATOR UNDER

VARYING CONDITIONS OF

TEMPERATURE

plied by the latent heat of the steam at
the given pressure gives the heat loss per
square foot of surface. Dividing this
loss by the difference in the temperature
between the steam in the radiator and the
temperature of the air in the room gives
the coefficient of heat transmission. Table
1 gives the coefficient of heat transmis-
sion for various radiators.

TABLE 1. HE.\T TRANS.MISSION FROM
DIRECT RADIATORS*

Type of Radiator

Square
Feet

Pounds
Con-
densed per
Hour per
Square
Foot

Coefli-
cient of
Trans-
mission

Cast Iron

48
48
45.3
36

12
42
48
48

Square

Feet per

Second

5

7
7
9
9

0.212
0.265
0.204
0.217

0.446
0.286
0.294
0.202

0.41
0.425

1.82

2 column

1.65
1.45

6 column

Wrought Iron

1.35
3.27

2 column

2.00
1.77

4 column. .*

1-in. Pipe tc.:

1 pipe liigh

4 pipes higti

Wall Coil
Section vertical. . .
Section horizontal.
Section vertical. . .
Section horizontal .
Section vertical. . .
Section horizontal .

1.27

2 , SO
2. 48

1.92
2.11
1.70
1.92
1.77
1.9S

Difference in

Coefficient of

Temperature

Transmission

SO

1.56

100

1.58

120

1.615

140

1.645

150

1.65

160

1.675

170

1.69

ISO

1.705

190

1.72

In order to determine how nearly con-
stant this coefficient remains, a series of
experiments were made at varying room
and steam temperatures. Table 2 gives
the results of these experiments. It will
be noticed that for ordinary conditions
of operation this coefficient remains
fairly constant so that it is hardly neces-
sary to take the variation into considera-
tion, except in very accurate work, and
then only where the range of tempera-
ture is very great does the variation in
this coefficient materially affect the heat
loss from the radiator.

The transmission of heat through radia-
tors and also the coefficient of transmis-

that were made at the University of
Michigan, the room used had very little
outside wall or window surface. Some
15 years later this apparatus was
moved into another room containing a
large amount of window surface. The
effect of this change was very marked.
The coefficient of transmission was raised
about 7 per cent. This accounts for the
fact that in greenhouse heating the rules
are entirely different from those used
for an ordinary house. Where radiators
are exposed so that the direct rays of
heat from the radiator strike directly on
cold glass surfaces at a low temperature
the radiation loss is measurably in-
creased. This is of great assistance to
the engineer, for if he figures his radia-
tion too low in a room with large glass
surfaces, he is helped by the fact that
the radiator gives off more heat and tends
to make up for the lack of surface.

The coefficients given in the previous
tables are for rooms having an average
amount of glass surface.

The transmission of heat through radi-
ators is also affected, to a small degree,
by humidity. The effect of humidity is
shown in Table 3.

TABLE 3. EFFECT OF HUMIDITY ON THE

TRANSMISSION OF HEAT THROUGH

C.\ST-IRON RADI.\TOR

Percentage of Moisture

Coefficient of

ture Saturation

Transmission

20

1 79

30

1.77

40

1 73

50

1.72

60

1.69

70

1.66

SO

1.63

90

1 61

It may be noticed that as the humidity
in the air increases, the heat losses from

July 4, 1911

P O >X' E R

33

the radiator diminish. This is contrary
to what might be expected, but the reason
for it is quite evident when carefully
considered. Water vapor occupies twice
the volume of air under the same pres-
sure, so that when the air in the room is
moistened, there is less weight of the
medium passing the radiator than when
the air is dry, and therefore less heat lost
by convection, which lowers the total
heat transmission. The effect of the
moisture in the air through the most ex-
treme ranges of humidity only changes

cent., and additional tests were conducted
with various enamels: japan, lead paint
and zinc paint. The results of these
tests are shown in Table 4.

In general the table shows that alum-
inum, copper and metal pigments in the
bronzes reduce the heat transmission.
This is probably largely due to the com-
position of the bronze and partly to the
vehicle which contains this pigment.
Enamel, lead paints and zinc paints al-
most all show no loss in heat transmis-
sion. The experiments show that the ef-

T.iBI.K 4. EFFECT OF PAINTINC. RAIHATOR.S

mission of heat and this point is at the
surface, so that the materials of which
the radiator is made (which is always a
good conductor) has very little effect.
For the same reason the thickness of the
metal composing the radiator has very
little effect.

In indirect radiators where the air
passes over the surface at a high veloc-
it\-. and this velocity is subject to a
wide range depending upon the condi-
tions of operation, it is necessary in de-
termining the coefficient of transmission

T.\BLE 5. COEFFICIENT OF TRAXSIIIS-
SION FOR INDIRECT PIN RADIATION

^

o
6
2:

Ij

5x

a

y

Remarks

»

74 4

222

n 413

2,82

0 997

Plain a.s received from -
factor.v

2

3
4

76 0

63.1
72.3

220

:;24

220

0 418

0.3.53
0.325

2 94

2.16
2.08

1.005

0.761
0 752

Plain a.s received from

factory
Painted with

copper bronze

copper bronze

Theiie paints,
of two coats
each, were
put on over
one another
in the order
given.

5

74.5

220

0.436

2.86

1.038

terra-cotla enamel

6

66.3

218

0 351

2 24

0.735

copper bronze
lignt-brown varnish

74.1

224

0.421

2.67

0 977

8

72 9

226

0 431

2 67

0.977

oak -brown varnish

9

71.8

225

0.318

1.97

0 7.30

aluminum bronze '

10

70.. 5

224

0.324

2.005

0.724

aluminum bronze ■,

11

66.7

223

0.442

2.68

0 970

silver-grav enamel

12

67.6

224

0 . 452

2.75

1 01

snow-white enamel

13

64.2

224

0.446

2.66

0 997

bronze-green enamel

This series
follows one
another.

14

64.0

224

0.429

2.545

0 9.56

no-luster green enamel

15

70.6

224

0.423

2.62

0.997

maroon-gloss japan

16

68.5

224

0.364

2.22

0 8.50

shellac and copper-

lironze powder

17

67,0

224

0.347

2.02

0 760

copper-bronze powder
and linseed oil ^

18

86.9

224

0.379

2.62

0 987

white paint >

19

83.4

224

0..389

2 65

1 00

terra-cot ta paint

20

86.8

224

0.374

2.59

0 , 9S!I

light-green paint

Painted over

2!

77.2

224

0.423

2.72

1 00

light-green paint zinc

one another.

22

77 7

224

0.408

2.66

0.964

tcrra-cotta paint zinc

23

76.0

224

0.418

2.70

1 01

white paint zinc
Radiator No. 2 plain in
all tests.

^

B.T.r. PER Horn

PER .'^Qi. ARE Foot

fJOLO

.ACTL AL .SlRFACE

°.-fe£

PER Degree Dlf-

FEREXCE Over

Isil

.\ir and Steam

Coefficient

e^'-

.Short

Long

Short

Long

^

Pin

Pin

Pin

50

0 .so

1.00

1.60

2.00

100

1 52

1.55

1.52

1.55

150

2.25

2.20

1.49

1.50

200

2.85

2.75

1.43

1.45

250

3.55

3.25.

1.42

1.30

300

4.25

3.70

1.415

1.23

350

4.85

4.20

1.385

1.20

to take into consideration the velocity
of the air passing over the surface as
well as the difference in temperature be-
tween that of the air outside and the
steam inside the radiator. The experi-
mental results go to show that this co-
efficient is almost constant and may be
determined in the following manner.
Divide the B.t.u. transmitted per hour
by the difference between the av-
erage temperature of the air pass-
ing the radiator and the steam in
the radiator. Divide this quotient by

the coefficient of transmission about 5
per cent.

The painting of radiators may material-
ly affect the transmission of heat. A
series of experiments were conducted
about two years ago to determine this ef-
fect. Two cast-iron rectangles were
used; one was painted and the other left
unpainted so that the painted radiator
was always compared with the same un-
painted radiator. The results of these
tests were very interesting. The radiators
were first tested both unpainted and the
condensation in the two was practically
alike. One radiator was then painted
with two coats of copper bronze and it
was found that the heat transmission
was reduced 24 per cent, from the orig-
inal cast iron. Two coats of copper
bronze were then placed upon a radiator
and the heat transmission was reduced
25 per cent. Two coats of terra-cotta
enamel were then placed over the four
previous coats and the heat transmission
was .3 per cent, better than the orig-
inal cast iron unpainted. This was re-
peated for 14 coats, the last two coats
being aluminum bronze. The transmis-
sion then showed a reduction of 27 per

COEFFICIENT OF TRANS.MI.SSION FOR FAN HEATER COII^
(OUT.SIDE TEMP.. 0 DEC.)

Velocity throioh Heater

'^

800

1000

1200

1400

1 600

'o

Vento

Pipe Coil

Vento

Pipe Coil

Vento

Pipe Coil

Vento

Pipe
Coil

Vento

PipeCoil

1

0 120

0 120

0 120

0 120

0 120

2

0 0595

0 0.535

0 0592

0 0575

0 0.59

0 058

0 0.585

0 058

0 058

0 0575

3

0 039H 0 03.50

0 0399

0 0379

0 040

n 040

0 041

0 041

0 042

0 040

4

0 0.301 0 0240

0 030

0 0289

0 0.30

0 030

0 038

0 030

0 039

0 030

5

0 0210 , 0 0160

0 0240

0 0203

0 0240

0 028

0 0240

0 030

0 0239

0 029

6

0.0198 , 0 0140

0 0199

0 0165

0 0199

0 019

0 0199

0 019

0 0198

0 019

7

0 0172 1 0 Oil

0 0171

0 0145

0 0170

0 017

0 0171

0 017

0 0171

0 0165

H

0 0149 0 009

0 0151

0 0125

0 01.50

0 0155

0 1.50

0 016

0 01.50

0.0155

feet is largely surface rather than con-
duction effect, and that the loss of heat
from radiators depends largely upon the
surface effect and to a very small extent
upon the conduction of heat through the
metals.

Experiments conducted with radiators
of the same shape made of different ma-
terials, cast iron, wrought iron and cop-
per, do not show a material difference in
the heat transmission when painted with
similar coatings. This is because the total
heat transmission is determined by the
point of greatest resistance to the trans-

the number of cubic feet of air pass-
ing per square foot surface per hour.
The final quotient will be the coefficient.
Table 5 gives this coefficient for an indi-
rect pin radiator of standard form
and for a long pin indirect radiator. The
irregular variations in the coefficient are
undoubtedly due to the errors in observa-
tion. It may be noticed that the coeffi-
cient increases as the velocity of the air
passing the radiator is increased.

Similar coefficients of transmission may
be obtained for fan-coil radiation. This
is determined in exactly the same way as

34

POWER

July 4, 1911

above with the exception that the final di-
visor is the velocity of air passing the
radiator in lineal feet per minute. Table
6 gives the coefficient of heat transmission
for 1-inch pipe fan coils. It may be
noticed from this table that the coefficient
varies with the depth of the fan-coil sur-
face. For any given number of sections
the coefficient remains approximately con-
stant.

The object of obtaining these coeffi-
cients is to enable the engineer to com-
pute approximately the heat losses in the
given forms of surfaces under all con-
ditions. These heat losses have been fair-
ly well determined by experiment for or-
dinary conditions of operation, but the en-
gineer frequently meets with conditions of
operation which are exceptional, and by
means of this coefficient he will be able to
ascertain the heat losses at least approx-
imately under these exceptional condi-
tions.

At the present time the university
is: carrying on an elaborate series of
e.\periments with fan heaters and w-ith
heating by hot water, and hopes that some
more definite information may be obtained
with reference to the effect of the velocity
upon the heat transmission through metal
surfaces.

LETTERS

Radiators Give Trouble

The layout submitted by B. E. Thomas,
of Seattle, in the June 13 number, in
which he requests readers to solve the
trouble he is having in draining his heat-
ing system properly, has attracted my
attention.

The I -inch line from the boiler feeds
radiator No. 1 on the first floor and Nos.
2, 3 and 4 on the second floor, in the
order named. The radiators drain in the
following order: Nos. 4, 3, 2 and 1 and
thence to the trap, using a single ' j-inch
line to drain all four radiators. Radiator
No. 1 on the first floor, being nearest the
boiler, receives the steam at a trifle
higher pressure and temperature than
do Nos. 2, 3 and 4. Using the tee con-
nection as Mr. Thomas shows at the point
.V to drain radiator No. 1 directs the com-
paratively hot steam upward as well as
downward; the result is a back pressure
in the return line Y which the condensa-
tion of radiators Nos. 2, 3 and 4 is unable
to overcome, and thus the return line V
gradually fills up and in due time the
condensation backs up into radiators Nos.
2, 3 and 4 on the second floor. A check
valve placed in the return line V' will not
overcome the trouble as the pressure
from radiator No. 1 is too great to allow
the valve to perform its duty as a check
valve. Therefore if Mr. Thomas would
place a 90-degree ell at point X, discard
the tee which the present layout shows,
cut out about 6 or 8 inches of pipe just
above the tee X and lead down to the

return line W with two 45-degree ells,
two nipples (one short, the other to suit
his requirements), and tie into the return
W with a Y or lateral, I think he would
thus overcome the back pressure from
radiator No. 1 and find that radiators
Nos. 2, 3 and 4 and the return Y would
remain free from accumulated condensa-
tion at all times.

Frederick R. Banks.
Paterson, N. J.

Chief among the reasons that the three
radiators on the second floor fill up with
water are the connections into the return
line from the radiators on the second
floor and from the radiator and pipe coil
on the first floor, thus introducing to the
return line at such points of connection
pressure sufficiently great to prevent the
passage of condensation from the sec-
ond-floor radiators.

ing that the trap is large enough to allow
all the water of condensation to pass
through it. An air cock should be shown
on each radiator, and to my mind the
K'-inch drip or return is much too small
for four radiators and a wall coil, even
if all the heaters were very small. Some
provision should be made to drain the 80
feet of 1-inch main at the supply end.
The connections are not put in accord-
ing to the best practice, but Mr. Thomas
does not ask whether the connections
are right or wrong; he only wants to
know how to get the radiators to heat
and keep them free from water. He
practically answers his own question
when he states that an open drain will do
the trick; all he has to do is to make
sure that the trap outlet is large enough
and that the trap works properly.

Ja.mes E. Noble.
Toronto, Can.

Radiators and Piping

The diagram exhibits other features
conducive to imperfect drainage of the
apparatus and the surest remedy for the
trouble is to disconnect the radiator and
the pipe coil on the first floor from
the return line and conduct these two
drips to a separate trap.

A. S. Mappett.

Philadelphia, Penn.

[Another letter along the same lines
as the above was received from Fred
Wagner, engineer of the Goodrich School,
Chicago, 111. — Editor.]

From the sketch I should say that the
return main from the radiators pitches
the wrong way and forms a pocket in
which the water collects and stops the
circulation. No air valves are shown on
the radiators, which would also stop the
circulation.

John Ednxards.

Boston, .Mass.

A much more satisfactory answer
could be given if the sizes of radiators,
main, wall coils, steam trap, etc., had
been stated, also the pressure on the
radiator side of the reducing valve. If
Mr. Thomas is correct in stating that
opening the trap drain operates the sys-
tem successfully, it would appear that
the only thing preventing the system
from working is a nonworking steam trap.
If the trap outlet is clear and the trap
in working order, it should carry away
the water as easily as the drain, assum-

Mr. Thomas says that when he opens
the drain from the trap, the water passes
out and the system works all right again
for eight to fifteen hours. This shows
that the system is all right and the
trouble is between the drain and the end
of the outlet pipe. Mr. Thomas does
not state to what the trap discharges.
If the trap discharges to the atmosphere.
I wouW think that the trap or the out-
let pipe is too small or partly stopped
up. If it discharges to a closed vessel
the same difficulty may result or the
pressure in the vessel may be greater
than that in the system.

WiLLlA.M SvroPE.

Tiffin, O.

July 4. 1911

POWER

35

B. R. I. Smoke Indicator

The B. R. I. smoke indicator has been
designed to indicate when excessive
smoke issues from chimneys and ro
enable the fireman to correct the evil.

The device consists, as shown in the
accompanying illustration, of a hinged
cone reflector and lamp A, attached to
the breaching, through which a strong
ray of light is reflected through a 6- or
8-inch pipe with suitable 45-degree re-
flectors B B. The light thrown on a
ground-glass screen placed in the sight
box or hood C reveals a large white

fVhat the in-
ventor and the manu -
fjcturer are doing to save
tiwe and money in the en-
gine room and power
house. Engine room
news

Harmon Feed Water Purifier

This device is designed for installation
in the steam space of marine and sta-

DlAGRA.MMATlC ViEW OF SMOKE INDICATOR

spot which changes in color as the flue
gases vary from pure white to jet black.
The sight hood is placed on the boiler-
room wall at a point visible for the en-
tire length of trie boiler fronts. This
enables the fireman to see the indicator
and at a glance ascertain the result of
any adjustment of air supply, steam jet
or furnace arrangement immediately
after making it and at the time when
he most needs the information.

As the ground-glass screen is pro-
tected by the hood, the device can be
used in the daytime as well as at night
and offers an unfailing and instantane-
lous indication of the condition of the
jfluc gases as they pass to the stack. The
Ismail holes shown at the elbow connec-
bions are for the purpose of admitting
lair into the pipes, thus preventing ed-

flies of smoke and soot from destroying
he brilliancy of the lamp and its re-
lector. Any number of bends may be
Tiade to bring the indicator to the proper
losition, the light being reflected on
hinged mirrors as shown. They can be
ppened and cleaned when necessary.
I The device is being placed upon the
kiarket by the Boiler-room Improvement

Company, 181 Van Buren street, Chi-

ago, III.

tionary boilers and consists of a series
of cast heads, held together by tie bolts,
as indicated in the illustration. It has
suitable baffle plates to deflect and retard

body of the device consists of galvanized
sheet casings, which may be easily re-
moved while cleaning. The purifier is at-
tached by hangers to the staybolts and
the feed water enters at one end and
passes out at the other. Precipitation is
caused by the heat of the steam. Blow-
of^ pipes are attached to the different
chambers where the sediment collects
and the purifier is blown off as frequent-
ly as the service requires.

After passing through the purifier the
feed water can be led to any desired
point inside the boiler if an increase
in the circulation is wanted. It is claimed
to be especially valuable in the case of
Scotch marine boilers, which are said
to have poor circulation at the bottom
of the shell. In the illustration the
purifier is shown installed in a boiler of
this type, with the \eed pipe extending
down to the bottom of the shell where
the hot water establishes circulation.

This device is patented by F. M. Har-
mon, 1304 Rockefeller building, Cleve-
land, O. The E. G. Todt Company, 9388
Ewing avenue. South Chicago, are the
Western agents.

The William Tod Company is running
more than full in the machine shop, but
the growing use of large steel castings
keeps their foundry output considerably
below its capacity. They deal with big
tnings and regard a lOOO-horsepower en-
gine as trivial. They have cast bedplates
weighing 220,000 pounds each, and have
ti-rned out the largest blowing engines
in the country with steam cylinders 56
.ind 108 inches in diameter, air cylinder
1 10 inches, stroke 60 inches. Each en-

Harmon FERn->rATER Hlater

the flow of feed water, that it may be
Intimately mixed with the steam. The

gine has a capacity of 60,000 cubic feel
of free air per minute.

36

P O \X' E R

July 4. 1911

A Self Cleaning Boiler

It has been often said that the time
to take the scale-making impurities out
of boiler- feed water is before it goes into
the boiler. From the boiler point of
view this cannot be gainsaid, and the
advantages enjoyed by a boiler fed by
pure water, the evaporation of tons of
which would leave nothing behind, would
be numerous and important. For the
small plant, however, even these ad-
vantages have not weighed sufficiently as
against the cost of installation and main-
tenance of a water-purifying apparatus to
lead to its general adoption, and the
smaller user clings to the practice of
making his boiler serve the double pur-
pose of a water purifier and a steam
maker, relying upon scale resolvents to
keep the deposits from crystallizing upon
the surfaces before they can be blown
out.

A boiler inspector with a wide experi-
ence has conceived an idea of a com-
promise by putting within a boiler a
chamber into which the feed water is
introduced and through which it is cir-
culated before being allowed to mingle
with the contents of the boiler proper.
In so circulating it will attain a tem-
perature at which the scale-making con-
tents will be liberated and be in sus-
pension without using chemicals of any
kind. As the movement of the water
through the chamber is very slow and as
the density of the hot water is low (56
pounds per cubic foot at the temperature
corresponding to 100 pounds pressure as
against over 62 pounds at 60 degrees) . the
precipitates settle out easily and may be
removed by blowing off. A trap prevents
the surface water from passing to the
boiler, and an occasional emptying of the
tank will remove such floating impurities
through the same blowoff.

A boiler embodying this feature and
made according to the drawing repro-
duced herewith was tested at Paterson,
N. J., recently. The shell is 42 inches by
9 feet and contains 88 two-inch tubes,
each 7 feet long. Riveted to the ring
flange is a cylinder of thin plate, 34
inches in diameter and 56 inches in
hight, making with the outside shell an
annular chamber (C C C C in the plan)
4 inches in width and with its top con-
siderably above the top of the gage glass.
This chamber is divided by the bafflles £
and F (see plan), those designated by E
having their lower ends 7 inches from
the bottom of the tank, so that the water
can pass beneath them, and those desig-
nated by F being in contact with the bot-
tom of the tank, but so short that the
water can flow over their tops. The feed
enters at the left as shown in both the
plan and elevation, through a ^j-inch
pipe having an area of about ' '■ a
square inch, and can flow outward from
the first chamber through two openings
beneath the partitions E E. giving an
area of

4 X 7 X 2 = 56 square inches,
or a reduction of velocity in a ratio of
112 to 1. Since the partitions F divide
the chainber at the bottom, separate blow-
offs for the two sides are provided as
shown. When the water arrives in the
right-hand chamber and attains the level
of the overflow, it is discharged as shown,
and as the trap draws from about the
center of the chamber, floating impurities
are retained upon the surface. The ca'pa-

Sectional View of Boiler

city of the annular chamber is about 100
gallons or 833 pounds, which would sup-
ply the boiler at its normal capacity for
nearly an hour.

Remaining in the chamber for this
length of time, exposed to the hot water
on the inside surface, open to the steam
at the top and compelled by the baffles
to follow a definite course, the feed water
is heated nearly or quite to the tem-
perature of the boiling water before it
is admitted to the boiler proper, and as

even the sulphates are precipitated at 280
degrees, the water as it goes to the boiler
is practically pure. As no flame comes
in contact with the chamber in which
they are deposited there is no tendency
for the deposits to bake on and form
scale, and they are easily removed by a
periodic use of the blowoff.

The test of the boiler extended over
several days and was very severe. The
water carried naturally 5 grains per gal-
lon and was loaded with 70 grains of
calcium and 70 grains of earth, a total of
145 grains per gallon. The feed was
taken from a barrel and was agitated by
the introduction of carbonic-acid gas with
a view of forming carbonate of calcium.
During the test the blowoffs to the sep-
arating chamber were plugged, thus re-
taining the sediment. The bottom blowoff
was also plugged. Considerable trouble
was experienced with the injector as the
feed water was purposely very muddy
and far worse than any encountered in
ordinary service. After some 1200 gal-
lons of this kind of water had been
passed through the boiler it was allowed
to cool and the heating surfaces were
found to be perfectly clean and the im-
purities retained in the chamber.

This boiler was designed and patented
by T. T. Parker, of Hackensack. N. J.

The Bartlett-Graver Water
Softener and Purifier

This device is of the automatic con-
tinuous type, in that the water is auto-
iratically softened in the same quantity
as water is withdrawn from the system.
The mechanical features of operation and
regulation will be apparent from the sec-
tional illustration shown herewith.

The water to be treated flows into a
distributing tank A. in which it is divided
into three streams, the main portion flow-
ing through the opening B to the down-
take C. A second portion flows through
the opening D into the control tank E,
and a third portion passes through the
opening F into the chemical tank G. In-
asmuch as these three openings are upon
the same level they each receive an ex-
act measure of the water entering the
tank, the amount depending upon the
head of water above the openings.

The chemicals, in the form of suspen-
sion, are kept agitated by means of the '
inclined paddles H, motion being ob-
tained from the waterwheel shown, which
is operated by the main body of water |
falling into the softener. Proper amounts
of lime and soda ash are placed in the
chemical tank and water is added until
the level of the solution stands at the (
edge of the overflow opening /. The quan-
tity of chemicals added to the hard water
is then governed by the amount of water
flowing through the opening into the
chemical tank. This water is immediately
mixed with the chemicals and displaces
an equal volume of solution through the

July 4. 1911

POWER

overflow J into the main tody of the soft-
ener K. The water thus added weakens
the chemical solution, and in order to
continually displace the proper amount
of chemicals the quantity of water added
must be gradually increased in direct
proportion to the dilution of the reagents.

Sectional View of Water Softener
AND Purifier

This increased flow is accomplished by
increasing the area of the opening F and
by raising the tapered plug /-, the posi-
tion of which is governed by the float M
in the control tank. As a fixed propor-
tion of the water entering the system
flows info this tank, the level of the
water rises in direct proportion to the
amount of water which has been treated
and raises the tapered plug or cone so as
to increase the opening in direct propor-
tion to the amount of water which is
being used.

Chemical reaction takes place as the
water and reagents descend into the cen-
tral portion of the purifier, the precipi-
tate collecting as a sludge in the bottom
of the main reser\'oir. Water is drawn
from the softener at the top, after it has
passed through a filter of excelsior. In
some forms of the device a quartz filter
is used.

The water softener is built by the Wil-
liam Graver Tank Works, Chicago, III.

The price of municipally produced cur-
rent in Munich is 20 pfennigs 'about 5
cents) per kilowatt-hour.

Impnncci Cookson Heater

If the inierior of the heating system
is to be kept from fouling, or the con-
densation from a hotwell or receiver is
to be reused, a large oil separator is nec-
essary. The new Cookson cast-iron
heater, shown in Fig. 1, has an oil sep-
arator big enough to purify all the ex-
haust steam from all of the boilers or
engines of the greatest capacity which

tical exhaust line without disturbing the
pipe except to remove a short length
necessary to admit the separator.

This construction greatly reduces com-
plications in piping, valves and fittings
and in the labor of installing. In plants
where all the exhaust steam comes
through one large pipe to a number of
heaters the minimum of pipe bends are
required to make the heaters deliver into
a common stack, and any of the heaters

Fic. I. Semi-sectional View of tiik Nf.vx Cookson Heater

the heater can serve. Fig. 2 shows an
exterior view of the heater.

This healer is made with a cutout valve
«ithin the separator, which permits the
heater being cut out for cleaning without
interfering with the functions of the oil
separator. It has exhaust inlet and out-
let connections in a direct line to per-
mit the heater to be inserted in a ver-

may be cut out for cleaning while the
others continue in operation.

Separation of oil and water is accom-
plished by changing the direction of the
current and expansion as follows: Ex-
haust steam enters the separator from
the bottom and leaves through the out-
let at the top. As the steam leaves the
engine exhaust pipe if passes first through

38

a tube projecting inwardly on the inlet
flange and opens at an angle opposite the
opening on the heater inlet tube. The
steam is then divided by a V-shaped
ribbed baffle cast on the underpart of the
heater inlet tube, which deflects the cur-
rent to the separator walls. The steam
currents therefore make nearly a right
angle and must travel back again be-
fore they reach the exhaust outlet or
the inlet tubes to the steam chamber of
the heater. Meantime the oil and water
particles, due to their greater weight, are
dashed against the separator walls, which
are ribbed their full length and breadth.
Oil and water carried down these ribs
fall into a well formed around the ex-
haust inlet tube, but out of the steam
current. This well drains through a bal-
anced float trap (or water seal, if there
is no pressure within the heater to re-
quire the use of a trap) and empties into
the heater overflow pipe. As the oil
drain connects to the overflow pipe bc--
low the valve in this pipe the separator
can drain through the trap when the
heater is cut out and the overflow valve
shut, thus preventing the entrance of
steam from the separator drain into the
heater through the overflow pipe.

All steam not going to the heater
passes through a tube on the outlet flange
similar to that on the inlet flange, but
sloping downward and with the angle
opening in the opposite direction to that
on the inlet, thus compelling the steam
to travel in an opposite direction to that
in which it entered. This tube also pre-
vents any water or oil that might travel
upward on the inside surfaces of the
separator casing from mingling with the
outgoing steam.

Steam for the heater passes through
the central horizontal tube, which is
faced on the outer end to form a tight
seat for a valve actuated from the out-
side of the separator. This valve may be
opened or closed at will to regulate the
■nnow to the heater. Steam is drawn into
the heating chamber on the vacuum or
induction principle by a partial vacuum
therein, due to the condensation of the
steam. Each impulse of the engine fur-
ther tends to drive steam into the heater
The overflow cutout is merely a stand-
ard globe valve, and the separator cutout
IS practically the same. Both are posi-
tive and close tight when the heater is
cut out. Such valves having flat seats
with disks held in place both by positive
parts and by the pressure of exhaust
steam are not likely to leak, and if they
do the seats can easily be reground. The
separator valve can be removed through
the flanged opening without taking the
separator apart or disconnecting any
piping. '^ ■>

The cold water comes in near the top
of the heater to a spray box which is
notched on the edge to spread the water
in small streams onto the top trav and
successively in a thin layer over th

P O W E R

other trays and into the reservoir. A
balanced valve in the water line operated
by a copper float on the water level regu-
lates the flow of cold water. The trays
are readily removed through the upper
door when the deposit of impurities
renders cleaning advisable. Gases liber-
ated in heating go to the top of the heat-
ing chamber, from which a vent permits
them to escape to the atmosphere or into
the exhaust outlet.

The water is prevented from rising
above a desirable level and provision is
made for skimming the reservoir surface
by an overflow plate that extends hori-

July 4, I9I1

i« therefore accomplished by merely hold-
ing the cold-water valve open until the
reservoir level goes above the overflow
line.

The filtering material, usually coke,
is supported by a removable perforated
cast-iron plate which prevents any filter-
ing material from getting into the lower
or settling chamber. This lower cham-
ber has at the bottom two flat surfaces
sloping to a common gutter at the cen-
ter. Any minute particles that pass
through the filter naturally fall toward
this gutter and are removed by opening
the blowoff valve.

Fig. 2. Exterior View of the New Cockson Heater

zontally the depth of the heater and
drains an even sheet of water into the
overflow pipe. The difference between
normal and overflow levels is suffi-
cient to take care of any sudden
large discharge of water into the
heater as from steam traps, or
slugs from the heating lines. The trap
in the overflow line automatically lets
this water out into the waste pipe without
letting any air into or steam out of the
heater. The removal of anv oil or other
impurities floating on the water surface

Where the heater need not be cleaned
while the exhaust steam passes through
the separator, the cutout valve is unnec-
essary and the heater is furnished with
the large separator, but without the valve.

If there is no back-pressure valve
in the exhaust line, as with engines ex-
hausting entirely to the atmosphere, pro-
vision against pressure within the heater
IS unnecessary and the trap is replaced
by a water seal.

The Cookson heater is made by the
Bates Machine Company, Joliet. 111.

UBfiBHftgMpUlH

July 4, 1911

POWER

39

California N. A. S. E. State
Convention

The eighth annual convention of the
California State association of the Na-
tional Association of Stationary Engi-
neers was held at San Francisco, June
6 to 8, under the auspices of the local
associations No. 1 and No. 3. The head-
quarters was at the Union Square hotsi,
and the various business meetings were
conducted at the Merchants' Exchange
building. Of the 44 delegates elected
to represent the six associations in the
State, 32 were present.

Owing to the labor controversies of
the union organizations of the city, which
have somewhat affected the local mem-
bers, there was unusual delay in call-
ing the meeting, notification being is-
sued only 20 days in advance. This ne-
cessitated the omission of the customary
exhibit feature as well as the prepara-
tion of any papers.

Respecting the labor-union troubles,
it was resolved at the opening assembly
on June 6 that the association members
would remain entirely neutral in any
controversy between employers of engi-
neers and the engineers themselves. A
committee was appointed, composed of
one member from each State association,
with John Topham, Los Angeles, as
chairman, to draft a State license law,
to be presented during the coming year.

In lieu of exhibits an attractive en-

Santa Barbara; secretary, W. T. W. Curl,
Los Angeles: treasurer, Charles Knight,
San Francisco; doorkeeper, Philip En-
nor. It was voted to hold the next an-
nual convention at Santa Barbara.

Mr. Brian, the State president-elect,
has been vice-president of the State as-
sociation during the past year; he was
president of Los Angeles Association
No. 2 in 1905. Mr. Curl has been con-
tinuously elected secretary of the State
association since its inception, eight
years ago.

The Los Angeles Association No. 2 is
the second largest in the United States,
having 444 members, and being only ex-
ceeded by Chicago' Association No. 1,
which has a membership of about 500.
The San Francisco Associations No. 1
and No. 3 total collectively 350 mem-
bers. An effort is to be made during the
coming year to establish local orders at
San Diego, Oakland and Sacramento.

Gas and Gasolene Engine
Trades Meet at De-
troit

With an attendance fully equal to any
of the former meetings, the regular semi-
annual convention of the National Gas
and Gasoline Engine Trades Association
was held. June 20 to 23, at Detroit. Presi-
dent C. O. Hamilton presided throughout
the sessions, while the city of Detroit

Magnetos," by R. A. Oglesby; "Gas-En-
gine Castings," by J. S. Van Cleve;
"Advertising the Association." by E. St.
Elmo Lewis; "Boosting the Gas-Engine
Business," by Albert Stritmaiter, and
"Aeronautical Motors," by E. W. Roberts.

One of the innovations of the meeting
was the dividing of the membership in-
to three sections, under the headings
"Engines," O. C. Parker, chairman;
"Accessories," M. A. Lceb, chairman,
and "Trade Press," E. J. Perkins, chair-
man, for the discussion of subjects of
special interest to the different divisions.
This will be continued in the future. The
trade-press section introduced a resolu-
tion to have a publicity board created
for collecting and distributing informa-
tion of technical interest regarding the
association. Action on this was deferred.
A steamer ride to the St. Clair Flats as
guests of the city of Detroit was one
of the most enjoyable social features.
During the trip a stop was made at the
New Menue Club, where a six-o'clock
dinner was served.

Cleveland was selected as the place
of next meeting, the date of which will
be in December of the present year.

Connecticut Engineers Hold
Convention at Hartford

The sixteenth annual convention of
the Connecticut State Association of the
National Association of Stationary Engi-

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tertainment program was arranged for
the visitors, with special sight-seeing
trips for the ladies. On Tuesday evening
a theater party was held at the Orpheum;
on Thursday night an elaborate dinner
pally was given at the Union Square
hotel; on Friday a four-hour trip was
taken about the bay in the United Slates
steamer "General Mifflin." Many of the
guests remained until Saturday, spend-
ing the day in visiting the interesting
parts of the city.

The following officers were elected
for the ensuing year: President, David
Brian, Los Angeles, succeeding H. W.
Noethieg; vice-president, L. E. Porter,

was represented at the opening exercises
by Lucius P. Wilson, L,ecretary of the
Chamber of Commerce.

The program included the following
papers, some of which will be abstracted
in a later issue: "The M.ngnitude of 'he
Marine-Engine Business," by H. G. Dic-
fendorf; "The Relation of Ignition to
the Sales Department," by R. H. Combs;
"Farm Power," by J. E. Waggoner; "The
Colleges and Gasoline Engines," by j. B.
Davidson; "The Commercial Side of
Farm Power," by E. P. Edwards; "Dry-
Cell Data fir the Engine Manufacturers,"
by F. L. White; "The Problems Pre-
sented to Manufacturers by Users of

neers was held at Hartford on Friday
and Saturday, June 2.^ and 24, with head-
quarters at the Garde hotel.

The Puinam Phalanx Armory, con-
veniently located a short distance from
the hotel, was selected for holding the
meetings of the delegates and also for
the mechanical exhibit under the auspices
of the Connecticut Stale Supplymen's
Association.

The large drill room of the armory
proved an ideal site for the display of
power-plant equipment. The hall was
tastefully decorated, and there ^Mas
abundant light from the windows on
either side of the room. Considerable

40

POWER

July 4. 1911

skill was shown by the committee in
the attractive arrangement of the booths.
A large space in the center of the hall
in front of the platform was plentifully
supplied with comfortable seats, and was
reserved as a general reception room.
The engineering public liberally patron-
ized the exhibit during the two days.

The meetings of the delegates were
held in the officers' room, immediately
adjoining the exhibit hall.

At twelve o'clock noon on Friday the
first session of the delegates was called
to order by State President Charles H.
Ostrander, A-ho made a short address and
appointed the necessary committees.

At eight o'clock on Friday evening the
formal opening of the convention took
place. The hall w-as comfortably filled.
State President Ostrander in a brief
speech introduced Mayor Edward L.
Smith, who cordially welcomed the con-
vention to Hartford.

National Vice-President Edward H.
Kearney responded for the engineers in

The election of State officers for the
ensuing year resulted as follows: F. L.
Chapman, of Norwich, president; T. J.
Phillips, of Hartford, vice-president;
N. J. Blacker, of Waterbury, secretary;
Thomas Reed, of New Haven, conductor;
Henry Heckler, of New Haven, door-
keeper; Frank N. Hastings, of .'Aeriden,
State deputy. P. J. Grace, of Bridge-
port, George P. Thomas, of Norwich,
and Walter B. Holt, of* New Haven, were
selected as trustees.

The officers were installed by State
Deputy J. A. Landon.

The next annual convention will be
held at Bridgeport.

At a meeting held by the Connecticut
State Supplymen's Association on Satur-
day morning there was a unanimous re-
election of the officers as follows: F. S.
Bulkley, Garlock Packing Company,
president; R. H. Stiles, Jenkins Brothers,
secretary-treasurer; John Foote, McLeod
& Henry Company; J. B. Harrington,
William R. Winn Company; F. P. Upson,

pany, Baldwin & Stewart Company,
Charles A. Claflin & Co., Connecticut
Metal Boiler Cleaner Company, M. T.
Davidson Company, Dearborn Drug and
Chemical Works, Franklin Electric Man-
ufacturing Company, Garlock Packing
Company, General Electric Company,
Greene, Tweed & Co., A. W. Harris Oil
Company, Harrison Safety Boiler Works,
Hartford Steam Boiler Inspection and
Insurance Company, Home Rubber Com-
pany, W. J. Hyland .Manufacturing Com-
pany, The Iron Works Company, Jenkins
Brothers, H. W. Johns-Manville Com-
pany, Keystone Lubricating Company.
Lake Erie Boiler Compound Company,
Long Grate Bar Company, Lunkenheimer
Company, McLeod & Henry Company,
Mason Regulator Company, C. S. Mer-
sick Company, the National Engineer,
New England Engineer, George M. New-
hall Engineering Company, New York
Belting and Packing Company, Nightin-
gale & Childs. Ohio Blower Company,
Perfection Grate Company, Power,

H^"^Vil

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Delegates and Visitors at Connecticut State Convention

a fitting manner, .^s a close to the
ceremonies an entertainment was given
by Billy Murray, of Jenkins Brothers;
Jim Devins, of the Peerless Rubber Man-
ufacturing Company; Frank Corbett, of
the Consolidated Safety Valve Company;
Edward Jeffe, and Jack Annour, of
Power. Later on, the supplymen enter-
tained the engineers in the grill room
of the Garde hotel, A. R. Foley, Home
Rubber Company, and C. F. Heitzmann,
Peerless Rubber Manufacturing Com-
pany, presiding.

At the meeting of the delegates on
Saturday morning the reports of the vari-
ous committees were read and adopted
and other important business was trans-
acted.

It is the prevailing opinion of the com-
mittee in charge of the license bill that
there is a good chance of its being favor-
ably reported at the next session of the
legislature. The bill is now in the hands
of the labor committee of the legislature.

Hartford Mill and Supply Company;
executive board.

On Saturday afternoon special trolley
cars conveyed the company to Long's
Farm, Newington, a pleasant suburb of
Hartford, to enjoy a family outing. Up-
on arrival refreshments were served,
after which a baseball match was played
between the engineers and supplymen
which resulted in a decided victory to the
engineers by the score of 9 to 1. After
the game dinner was announced and the
party repaired to the tables to partake
of an appetizing old-fashioned clambake,
which brought to a close the most suc-
cessful convention yet held by the Con-
necticut State Association.

There were a greater number of ex-
hibitors this year than heretofore, about
forty firms occupying booths as follows:
American Steam Gau<:e and Valve .Man-
ufacturing Company, Ashton Valve Com-
pany, Autogenous Welding Equipment
Company, Automatic Steam Trap Com-

Practical Engineer, Roto Company, Save
Oil Company, Travelers Insurance Com-
pany. Universal Lubricator Company.
William R. Winn, representing the
Quaker City Rubber Company. The
Hartford Mill Supply Company had sev-
eral booths and exhibited for the fol-
lowing fi"^ s, Adam Cook's Sons, Jeffer-
son Unio 1 Company, Manzel Brothers,
Patterson- -^ en Engineering Company,
William Powill Company, S-C Regulator
Company, C. E. Squires Company, R. G.
Von Kokeritz Company.

A Correction

In giving the list of exhibitors at the
Philadelphia convention of the American
Order of Steam Engineers in the issue
of June 20, page 980, we inadvertently
used one "r" too many in spelling
Parkesburg when referring to the firm of
Parkesburg Iron Company, located at
Parkesburg, Penn.

July 4, 191!

POWER

Incorporation of the Institute
of Operating Engineers

On Saturday night, June 17, some 100
members of the Institute of Operating
Engineers met in the Engineering So-
cieties building, New YorJ; City, for the
purpose of taking the necessary pre-
liminary steps to incorporate under the
laws of the State of New York.

The meeting was called to order by
H. E. Collins. J. C. Jurgensen was
made temporary chairman and Mr. Col-
lins secretary.

In his introductory address, Mr. Jur-
gensen drew attention to the fact that
in the United States alone there are
some 750,000 men directly engaged in
the care and operation of power-generat-
ing machinery, representing a capacity
of 16.000,000 horsepower and a monetary
value of $1,440,000,000. In tracing the
development of the institute he stated
that the present enrolment includes men
in practically every State of the Union
and in Canada, Mexico, the Philippines
and India.

The present membership is 326. The
institute has been progressing in tem-
porary form since March. 1910.

After Mr. Jurgensen had concluded his
remarks, two formal resolutions author-
izing the legal incorporation of the body
were passed. The petition for a charter
was signed by the following members
of the executive committee: J. C. Jur-
gensen, H. E. Collins, Willis Lawrence,
F. J. Eastment, W. F. P. Hill, J. C.
Stewart, F. L. Johnson. W. D. Ennis,
J. G. Quid, W. G. Freer and L. Hou-
miller.

Prof. W. D. Ennis, of the Polytechnic
Institute of Brooklyn, stated that after
mature consideration he felt that a mem-
bership of 3000 could be attained with-
in six months.

A. R. Maujer, who followed Professor
Ennis, urged enthusiasm as a valuable
asset for the young organization and a
general spirit of "boost" on the part
of the members.

Wilson Van Buren, editor of The En-
gineer's List, spoke briefly in indorse-
ment of the aims and methods of the
institute.

D. B. Hcilman, mastei nechanic of the
Philadelphia & Readinp .Railroad, gave
■ straightforward, encnu.-aging talk on
the prospects of branch organization
thrnughout this country.

Willis Laurence, chief engineer of the
Interborough Raoid Transit Company,
In his usual happy vein, contrasted the
status of the engineer with that of the
apartment-house janitor and referred to
the work of the institute in standardiz-
ing grades of membership as doing for
organization what standardized machin-
ery and efficiencies do for equipment.

J. G. Ould. of the Polhcmus Clinic,
one of the pioneers in operating-cngi-
reering education, forecasted a steady in-

crease in the standards of educational
requirements.

Timothy Healy predicted a sound
financial reward for those who by study
and practice improve their qualifications.

F. L. Johnson delivered one of his
characteristic "charges to the jury" and
asserted that unqualified success seemed
assured for the Institute of Operating
Engineers.

The annual meeting of the institute has
been fixed for Friday, September 1, by
which time it is hoped that in member-
ship and financial resources the organ-
ization will be in a permanently sound
condition. Branches have been started
in Manhattan and Brooklyn boroughs of
New York City, Chicago, Binghamton,
N. Y., Yazoo City, Miss., and Providence,
R. I. The membership is increasing at
an accelerated rate, 104 members being
enrolled since Februarv 1.

Rendering Boiler Accident

A serious accident occurred in the
works of the Newburgh Rendering Com-
pany, Newburgh, N. Y., on June 20, in
which one man was killed.

A large boiler used for rendering pur-
poses and carrying 40 pounds pressure
began to leak around a 14-inch manhole
cover. This cover was fastened by two
lugs and shackles. A bar of iron with a
large tee-bolt was used to tighten up the
joint. On noticing the leak the engineer
tried to tighten up the tee-bolt by plac-
ing a piece of pipe ever the end, thereby
overstraining the parts. One of the
shackles gave way, the cover blew off
and the contents were strewn all over
the engineer, resulting in his death.

It appears that he had done this time
and again, although cautioned to the
contrary.

Colorado Plants Purcha.sed

H. M. Byllesby & Co. have purchased
the Pueblo & Suburban Traction and
Lighting Company and allied interests in
Colorado, the property being taken over
June 14. This company operates the
street-railway system of Pueblo and sup-
plies electricity to Pueblo and the Cripple
Creek gold-mining district, including the
cities of Cripple Creek, Victor and Gold-
field. The towns of La Junta and Rocky-
ford arc served with electricity by sub-
sidiary corporations.

A steam-electric power station of 4I3.S
kilowatts at Pueblo and a hydraulic
power plant of 1600 kilowatts at Skaguay
arc operated. Arrangements arc being
made to increase the capacity of the
steam station at Pueblo and to extend
transmission lines to serve additional
cities and towns. Additional hydroelec-
tric developments are also contemplated.
W. F. Rabcr is at present in charge of
management for Byllesby & Co.

PERSONAL

B. W. Slocum, who for the past six
years has been chief engineer in charge
of the plants of the Portland Railway,
Light and Power Company, has recently
been made manager of the Oregon Dry
Dock Company. Portland, Ore.

John J. Calahan has been appointed
supervising engineer of schools and chief
engineer of the high school at Jersey
City, N. J. He will supervise the work
of the janitors and janitor-engineers of
all schools in that city, including the
inspection of construction of the tech-
nical and industrial high school.

Frederick K. Blanchard, 422 River
street, Troy, N. Y., will represent the
Homestead Valve Manufacturing Com-
pany, of Pittsburg, in the cities of Albany
and Troy, N. Y., and vicinity. Mr.
Blanchard will have a stock of Home-
stead valves on hand at all times and
will be prepared to supply the engineers
and power plants of those cities on short
notice.

A. C. Scott is president of the Scott
Engineering Company, Dallas, Tex.,
which has just been organized and is
prepared to supervise either general or
special work in the following engineering
lines: Electrical, steam, gas, waterworks,
irrigation, refrigeration, reinforced con-
crete, heating and ventilation, Texas fuel
properties and tests of oil, coal and
lignite. Plans and specifications are also
furnished and reports made on power-
plant operation and economy.

SOCIETY NOTES

The Combined Associations of Engi-
neers, of Brooklyn, N! Y., held its an-
nual outing on Sunday, June 18. Two
special trains conveyed the engineers and
their guests to Bellwood park. N. J., a
most picturesque and appropriate resort
place. Dancing and outdoor sports of all
kinds were enjoyed. There was a long
program of races, first and second and
in many cases third prize; being pre-
sented to the winners. A ba!.."ball match
closed the day's fun. The igineers'
Blue Club played a nine pickec from the
Combined Associations of Engi leers, the
latter winning by the score of 1 1 to 6.

OBITUARY

Charles A. Hague, consulting engineer,
died on Sunday, June 2,S, at his home in
New York City. Mr. Hague was one
of the founders of the American Society
of Mechanical Engineers and a specialist
in pumping machinery and waterworks
engineering. He has had a long and
successful engineering career and leaves
behind him many friends in and out of
the profession.

42

P O W E R

July 4, 1911

(Continued from last u'cck\

WhoHasTheSay?

By C A. TUPPEK *

(In last week's issue it was shown that
today the operatins engineer is the man
lM>hihrt the sale — the man whose woid is law
in the Imyins of equipment for his plant.]

NOW about the consulting engi-
neer; where does he come in?
The consulting engineer of
today, who is "wise in his gene-
ration," does not interfere in the purchase of equipment further
than to make suggestions for the consideration of the owner
and his chief operating men. This applies to machinery of any
kind; but more particularly to power apparatus. The consult-
ing engineer concerns himself only with the layout of the plant,
and, beyond designating a certain standard of equipment neces-
sary to the successful working out of his plans, he docs not
ordinarily specify the exact makes of the apparatus to be bought.

There are, of course, exceptions to this. For example, a
newly incorporated company may be arranging for the erection
of a plant. Until ready to begin operations it will not have
need of an organization for operating. Consequently, the
consulting engineer not only draws the plans but usually super-
vises construction and takes bids for the equipment. A great
deal of machinery is annually purchased on that basis. The
consulting engineer is, therefore, not to be ignored. Far be it
from me to convey that impression.

But the vast majority of purchases will continue to be made
by concerns that do have a capable operating organization; and
such purchases are either for increasing the capacity of an
established plant or for equipping a new one made necessary by
the growth of the business.

When this is true, the consulting engineer who attempts to
dictate the buying of the machinery is treading on dangerous
ground. He immediately brings into antagonism with him the
engineers to whom its operation will be intrusted, and their criti-
cism, well Jirected, may discredit his entire work. That there
are not more is due to the fact that experience is usually an
efTectivc teacher.

What about the preference of the owner?

Such preference, if traced to its source, will almost invariably
be found in the record of machinery previously used, as inter-
preted to him by the men in his employ responsible for its
efficient operation. This preference is, no doubt, affected very
materially in its inception by the reading of the right sort of
advertisements, by what is seen at other plants, what is heard
at conventions and by his personal liking for the proprietors,
manager or salesmen of some machinery-building house. But
these are details that simply lead him to talk over the subject
with his engineer and have the latter investigate them for him.
It is the same when any salesman calls, in the regular course,
to present the superior merits of his machine. He is either
referred directly to the engineer in charge, or the claims which
he makes are noted down, to be taken up with the latter at a
convenient time.

Seldom, indeed, does the owner or executive official of any
concern make a decision, on his ow-n account, that is contrary
to the judgment of the engineer responsible for the successful
operation of the power plant.

The matter of price is, of course, a determining clement in
many cases where standard equipment is to be purchased.
That holds true of apparatus for any service. Even here, how-
ever, the operating engineer has a voice in the decision. His
first preference may give way to a second or a third; but no ma-
chinery will be bought, as a rule, that he does not indorse.

Similarly, whatever the man in charge of a power plant
condemns has no chance of acceptance, unless it can be shown
that he is mistaken. Occasionally such proof becomes necessary.
It is, however, a further demonstration of the inlluence of
the operating engineer that no experienced salesman will un-
cover any error of judgment, on the part of the former, in tlie

•Kormorlv with Allis-Chalmers Company.

presence of the owner or manager of a
plant, without first having a good talk
with the engineer opposing him.

Should he find the latter unduly
prejudiced, and obstinate in clinging to
his error, he has, naturally, no course
open but an appeal to higher authority:
but he will try every possible means to
avoid it.

I was once present at a conference
between the proprietor of a factory, his
engineer and the expert representative
of a machinery house, where the last
named acted without tact in exposing a
fault in the operating man's experience. The sale was hopeless-
ly lost from that moment, and, to my certain knowledge, no fur-
ther purchases have since been made from the concern whose
agent behaved so indiscreetly.

There are, unfortunately, a great many sales managers who
have had no actual selling experience in the field. In the cities
where these officials usually have their offices, they come into
frequent business intercourse with consulting engineers, meet
them at their clubs or on the golf links, and get to think that
such engineers practically control the selection of equipment.

A really good salesman, on the other hand, often fails to
reach the grade of sales manager because he has no executive
ability and would be out of place at a desk. Consequently, the
real influence of the operating engineer is frequently unrecog-
nized when it comes to advertising and selling campaigns.

It is remarkable, sometimes, how long such a condition can
last. 1 have in mind, at this moment, some very glaring exam-
ples where it has existed for years, with serious detriment to the
machinery manufacturers' interests.

The practical man in charge of a power-equipment coni-
pany's sales, however, whether he be the president, vice-presi-
dent, secretary, general manager or is kno\vn as sales manager,
has a lively appreciation of the operating man's importance.
He advertises directly to him, distributes literature with facts
appealing to his needs, cultivates his acquaintance at conventions
and has the company's representatives keep in touch with him
at every possible opportunity.

To keep continuously befcre the thousands of operating
engineers now employed in this country alone is, however, a task
of stupendous proportions. A mailing list, carefully selected and
maintained, enables circular matter to be distributed to advan-
tage, but the cheapest and most effective means of reaching
them is, of course, through the paper that the engineer regu-
larly reads.

Nor does a card or stereotyped advertisement serve that
purpose well.

Announcements in the space that is purchased should be
so prepared as to convey a message to the operating engineer,
precisely as a good salesman would talk.

The man in charge of a power plant is not particularly
interested in the claim that you build the world's best machinery:
others have done so and passed along. But, if you can give
him facts concerning its construction and operation that appeal
to his judgment, he uill be as glad to read them as you arc to h :;<"
him do so.

The reading columns of a good class journal, while barred
to worthless "write-ups," are also open to information of any
kind that will really interest its readers; and power-machinery
manufacturers who make a practice cf supplying it are given a
further opportunity of keeping before the operating engineer.

To all such I would say: "Treat of theory only so far as
it explains desirable features of design; avoid the commonplace
details of construction and bring out clearly just what service
the machinery or other apparatus will perform. If operating
tests and records arc available, give them with sufficient full-
ness to render them convincing and state just where and how
they were secured. Then, when your salesmen go on their
rounds, they will find interested listeners among the men in
charge' of the plants where you hope to place your equipment.

" But, whatever you do, don't make the mistake of ignoring
the operating engineer. Leave that to the men who never sold
goods, but know all about how- it should be done."

\'n

NE\\' YORK, JULY 11, 1911

THE biggest room in the world is the room for
improvement; it knows no limits; it reaches
from the guest room in the White House to
the ash pile in the yard of the isolated one-unit plant,
from the Government official to the President, from
the chief to the boy who sweeps up. There is always
room and there always will be. Perfection is never
reached in anything.

If an efficiency from certain apparatus of 75
or 80 per cent, is obtained, that is verv^ good. How
about the missing 20 or 25 per cent.; did you ever
think of how it might be reduced? It is not impossible
by any means; a hundred years from now they may
only be wanting 16 per cent., but so long as the " want-
ing" is there, so will the room for improvement be.

The most important room for imjirovement that
we directly control is the improvement of one's self.
The road to it may be broad, but it may be easily
narrowed; one thing sure, it never has the "closed"
sign on it. It is not a hard road; it is easy if you
know how to adapt yourself to it, to travel at the
pace that improvement demands. To be on this
road simply means having reasonable and sensible
ambitions, being progressive and keeping abreast of
the things which arc needed in the business, being
alive to the opportunities ofTered in life. When we
stand still, when we think we "know it all" and would
rather sneer at the fellow who is " plugging away at it,"
we are in that room adjoining of no-imjirovcment,
and ten to one the "plugger" will beat us out; just
keep your eye on him.

To start and to keep on the road of improvement
re(|uircs two things: common sense and a little i)ersonal
cfTort. While we are lounging at the desk, listening to
the "tune," we are offered a mighty gr)od chance to
better ourselves, to increase our knowledge by reading
Sfnnething worth while — not sensational newspaper
stuff or comic supplements — for life is too short if one
has a living tf> earn. Remember, the fellow who wrote
it gels more material benefit than his reader; there
is a difference between such class of matter and that
of current topics.

\\1iile off duty, too, a man is continually given

a chance to improve his ability. All of us have a little
spare time if we w-ork under normal conditions. Is
there a public librar)^ in town, and do you ever go
there to see if there are any jiractical textbooks which
might be taken out for a few weeks? Do you ever
read the publishers' announcements to see what "is
doing" in the line of new, helpful books on the business,
and which may be obtained for a dollar or two? Often
a little money so invested has brought its investor
manifold returns, not only in the room for improve-
ment but in dollars and cents in .salarj-. The greater
our knowledge, tns more we know how to act in our
particular line, the more we get on pay day; and
further, the fellow who really knows, and can put it
in operation, rarely has to look for a job — the job
looks for him

Did you ever notice the difference between the
man who regularly gets a practical journal which keeps
hun uptodate, and the fellow who does not? And
that other chap who comes around everj' few weeks and
borrows the latest copy, and many times forgets to
return it. "He can't afford to subscribe," but he
probably expends many times the cost demanded
when he meets friends at the "restaurant," at noon.
The fellow w-ho will not spend a nickel a week, less
than one-half cent a day, to know what is going on
in his world is the fellow who skips any word which
relates to improvement; the big room of such as he is
quite likely to always be big. He is in a rut and, not
realizing, does not care; he is pretty .sure to remain
exactly where he is, and the fellow who is wide-awake
need not fear him.

Our road will ever be large, but it .should never
be allowed to expand; each day should see a little
traffic on it, and no matter how slight, it will always
help. The liberties of existence accorded those of
rational mind give to each individual his choice f)f
routes — the one to improvement, betterment and the
numerous possibilities contingent; the other, the road
to nowhere, where he stands idly wishing, watching
and waiting for the chance which never comes. Sup-
pose it did come, where is he tf) "make good" in com-
parison with a progressive engineer'

POWER

July 11, 1911

Olympic and Titanic, Ocean Giants

A mile is a considerable distance. To
judge the accuracy of this statement you
might get out and run a mile. If a mile
run is too big a contract at the start, you
might try a sixth of a mile, which con-
tains 880 feet. Even the latter distance
we feel will have your sincere respect
after you have breezed over it and per-
haps you will be able to appreciate in a
small way the vastncss of the two new-
est steamships of the White Star Line,
the "Olympic" and the "Titanic," which
are each 882 feet 6 inches long — more
than a sixth of a mile. They are the
largest ships in existence. Harland &
Wolff, Limited, Belfast, are the builders.

The "Olympic" completed her first
service trip at New York on June 21;
she is to run between New York, Ply-
mouth, Cherbourg, Southampton and New
York. The "Titanic" is in course of con-
struction at her builders' yards in Belfast
Lough, and is to be practically the same
in size and design as the "Olympic."

A view of the "Olympic" is given in
Fig. 1. These are her principal dimen-
sions: Length, 882 feet 6 inches; beam,

The two largest ships in
existence. The "Olympic",
ichich is mnc in service, is
propelled by two 15,000-
/; orsepower triple-expansion
engines and one 16,000-
horsepower exhaust-steam
turkine. She has a dis-
placement of 66,000 tons,
burns 800 tons of coal per
24 hours and makes 21
k]iots.

4(i,000 horsepower, 30,000 horsepower of
which is developed in reciprocating en-
gines and 16,000 in an exhaust steam tur-
bine. The ship has three propellers; the
reciprocating engines drive the outside
ones and the turbine the middle one. This
combination is most desirable as it in-
creases two things which are important

creases the comfort of the passengers.
It may then be asked why turbines were
net used exclusively and the noticeable
vibration completely eliminated. The ex-
planation is that the present arrangement
IS so satisfactory that an all-turbine in-
stallation would be but a very slight im-
provement in point of comfort while it
would be at a decided disadvantage when
reversing the boat.

Reciprocating Engines

The two reciprocating engines are of
the four-cylinder, tripU-expar.sion design,
the high-pressure cylinder is 54 inches,
the intermediate is 84 inches and the
two low-pressure cylinders are 97 inches
in diameter; the stroke is 75 inches. The
engines were designed to operate at a
speed of 75 revolutions per minute and
develop 15,000 horsepower with a boiler
pressure of 215 pounds and an exhaust
pressure of 9 pounds, absolute.

Low-pressure Turbine

The turbine is of the Parsons type. It
receives steam at 9 pounds, absolute, and

Nil ■■ ■■ ^■^'^'^'""^''ntTTiTri I I

11

i-^i^>^r-.t

Fig. 1. The White Star Line's Newest Ocean Liner "Olympic," Largest Ship Afloat

92 feet 6 inches; depth (keel to boat
deck), 97 feet 4 inches.

From the keel to the top of the fun-
nel is 165 feet; her gross tonnage is
45,000; her displacement tonnage is 66,-
000; there are 11 decks, four electric
elevators to carry the passengers from
one deck to another; accommodations for
2500 passengers are provided, and a crew
of 850 is carried.

To propel this enormous mass at a
speed of about 21 knots requires some

in ocean passenger steamer service: econ-
omy, and the comfort of the passengers.
The use of a low-pressure turbine makes
it possible to expand the steam much
further than could be done in any re-
ciprocating engine. Then the use of the
turbine greatly reduces the size of the
reciprocating engines compared with what
would be necessary if engines alone were
used and the ship had only two propel-
lers, and this reduction decreases the
noticeable vibration and consequently in-

expands it down to 1 pound, absolute.
The condensing equipment was designed
to produce a vacuum of 28' j inches with
the barometer at 30 inches and the tem-
perature of the cooling water between 55
and 60 degrees Fahrenheit. The normal
speed of the turbine is 165 revolutions
per minute and it develops about 16,000
horsepower when operating under the
conditions just described.

The rotor, shown in Fig. 2, is 12 feet
in diameter and 13 feet 8 inches long be-

July 11, 1911
tween the outside edges of the first and
'n length between 18 and 25- . inches

JiesT;"atr'r '■" ^'^-^^^^^

S eu^ht 'tsig" ^hT''^"""^ °^
„„ ■ "csign. ihe rectangular

opening at the far end of the casing s
ore T,T' °""'^ ^"'^ ^«""^"« direc' to

^^^.Hneofthes^X.-:--

b.ne dr.ves is ,6 feet 6 inches in dil:.

eter, has four blades and is made of
nianganese bronze. The two engine-
dnven propellers are 23 feet 6 inche fn
d.ameter have cast-steel bosses and thr "
bronze blades.

P O W E R

Arrangement for Reversing
,. ^If-^T" ^^0"! fhe boilers is admitted to
t' h,gh-pressure cylinder of each engine
by a s.ngle piston valve, while the !"!

-th a e;s n.' '"'""'' "°' '^-"S fi"^d

engines on ' ^'''' " '"""'^'' ^"^^ '^^
g'nes only are used to back water

and admLd to'th I'"'" '''^ '"^"''"'^

^ -e f ^'^:;::-S^-- one

^"?ts:s:^,-Lrar-^

.t7:l-ch'-^-"^"'---""^- -~

gear, wh.ch ,s supported on the bulkhead
and operated from the engineers' start
;ng platform by a lever near the re vers

When the order to reverse is given, the

45

concave disks of thin steel ^ f»». ■

The high-pressure steam n;„-
the boilers to the engteTis ';"' T

mam stop valves, 21 ' . inche<= fn h

-e located. E^ch Ca v s fitlr^'K

cross connections so that I thel ""

Of Piping may be used foeSrboTh

-S,ar:Sei-rf-^

X^S;;Sbn5^"-"

tnain stop valves there is f;" %'"'

-;ve on each engin:%'L^L r:S
but large enough to pass sufficient steam
o operate the engines slowly; S
valves alone are used when the ena
-e being handled, because Me- can "be^

z::tZs'''-' -°- -"V thr tJ:

FiC. 2. Tl R„:

r:f,v;r^The",r^''"'^"''-'-p--

r^ =/ . '"^-pressure cylinders

th;r:;rj"''\°''''-"«^^^^^

orked off'!"'"' ''" •"•' "«• valves

.^'4 d^^cT''" '"^-P^^^t^re cylinder,
hau;, nio 'l""'" ^ '^P-*^'dcd stee

s de of t "''"^ '""^""^ «f «'

« from H '?'"'• ''^"'^^■■' "^^ "-
er /„r ' "'"' '"^-pressure cyl-
er and enters what is described as a
'"n^e-over" valve, which i, u,ed .'n

!<"?'. K |-,,K T,

IE "Olv.mcic"

engneer first pulls over the "change-
,h Z, '^^•^^•■"■"g-gear lever, and

•hen sh.f.s ,he lever for reversing the
engmes. He need no, wait an instant
between these operations, for the steam
supply ,0 the turbine is completel cu^
off and the exhaust from the engines
passes directly to the condensers.
Piping
Each main-engine exhaust pipe i, s

eet m diameter. Expansion is' pUded
ror by placmg "concertina" ioints be-

t»een all pomts where the pipe I, rigidly
connected. These joints consist of Jo

tur1,inr'" 'V" '""^ f^'^^- 3 ""d 4 the
lurome cxhaii<;is i^, .1.

.ny«pc,.,c<,,i„,„..,„„,H., i';™-

The Boilers
feefpTncif '""T'' '" ^ f""'"". 15

end^d ^r2o^^lr••^^"^''-^'^

ended and iffcln S's on? S:
"c three fun,aces in the sinje-ended

46

POWER

July 11, 1911

boilers and six in the double, three at
each end. The furnaces are of the Mor-
rison type and all are 3 feet 9 inches in
diameter. The boiler shells are of
1 11/16-inch plate and made with only
one joint.

The boilers are contained in six water-
tight compartments. So great is the size
of the ship that it was possible to set
five boilers in a row athwartship. The
after boiler compartment contains the
single-ended boilers. These are so ar-
ranged as to be available for running the
auxiliary machinery while the ship is in
port, as well as for the general steam
supply when the ship is at sea. Two
boilers in each of two other compart-
ments have separate steam leads to the
auxiliary machinery, including, of course.

except in three of the compartments in
which there are independent ballast
pumps.

Air is supplied to the stokeholds by
electrically driven Sirocco fans, of which
there are 12, two for each boiler room.
The boilers are operated under natural
draft furnished by three of the four fun-
nels, the fourth being used exclusively
for ventilating purposes. The funnels
rise 150 feet above the grate bars and' are
oval in shape, 24 feet 6 inches by 19 feet.
Each stokehold is provided with Kilroy's
stoking indicators — electrically operated
signal disks and gongs, which inform the
fireman when each furnace is to be
stoked. The instruments are so set that
the minimum number of doors are open
at a time and no two opposite doors in

These bunkers are arranged on each side
of the main bulkheads and, therefore,
immediately in front of the furnaces;
hence, each fireman practically takes his
coal from the bunker door.

The coal consumption amounts to
something like 800 tons per 24 hours.
About 175 firemen and some 72 trim-
mers are carried.

Electric-generating Plant

Those who remember the early days
of the introduction of electricity on board
ship, when any old otherwise useless
corner was good enough in which to
stow the dynamo, would appreciate the
great importance to which this depart-
ment has now attamed on board ship
after an inspection of the palatial room

Fig. 3. The ••Ql^mimc's" Tlrbine Casing on the Assembly Fi ;■._■:<

the electric-lighting equipment. The five
other boiler compartments contain the
double-ended boilers; four contain five
boilers each while, owing to the fining
of the ship, the forward compartment
contains only four.

In each of the five large boiler com-
partments there are two See's ash ejec-
tors, and in addition there are four Rail-
ton & Campbell's ash hoists for use
when the ship is in port.

A duplex pump, manufactured by Hat-
land & Wolff, is contained in a separate
room in each boiler compartment. The
advantage of having the pump in a sep-
arate room is that the dust is excluded,
and hence the working parts are not af-
fected. This pump works the ash ejec-
tors and feeds the boilers as required; it
can also be used for pumping the bilges.

the same boiler are ever open during the
same period. The interval between the
times of firing is determined by the en-
gineer and changed as his judgment may
decide, but when the instrument is once
set, perfect regularity is secured and
economy is increased.

The boilers are fitted with Silley
wedge-action smoke-box door fasteners,
which do away with the usual multiplicity
of handles and tend to keep the doors
from warping. A complete telegraphic
outfit is used to inform the boiler-room
force of the requirements of the engine
room in regard to steam, etc.

There is a main coal bunker 'tween
decks immediately within the skin of the
ship. The coal is first loaded into this
and subsequently distributed into hunk-
ers athwartship at the stokehold level.

devoted to the generating p'ant on the
"Olympic."

There are four 400-kilowatt engine-
driven dynamos. The engines, which
indicate each about 5S0 horsepower, are
of the Allen vertical, three-crank, com-
pound type and run at 325 revolutions
per minute. Each engine has one high-
pressure cylinder, 17 inches in diameter,
and two low-pressure cylinders, each 20
inches in diameter; the stroke is 13
inches. The engines take steam at 185
pounds pressure. They exhaust either
into a surface heater — which is the usual
sea-going condition — or to the conden-
sers.

Forced lubrication is, of course, used,
with special arrangements tc prevent the
oil from getting into the cylinders and
thence to the boilers.

July 11. 1911

POWER

47

Each engine is direct coupled to a
compound-wound direct-current dynamo,
having an output of 4000 amperes at a
pressure of 100 volts. The dynamos
are of the ten-pole type and are fitted
with interpoles.

In addition to the four main generat-
ing unit3 there are two 30-kilowatt en-
gine-driven dynamos, in a recess off the
turbine room at the saloon-deck level.
These sets can be supplied with steam
from either of several of the boiler com-
partments and hence are available for
emergency purposes. They are of a
similar description to the main sets ex-
cept that the engines arc of the two-
crank type.

The distribution of current is effected
on the sinsle-wire system, and is con-
trolled and metered at a main switch-
board placed on a gallery in the dynamo
room to which the main dynamo cables
and the main feeders are connected.
The latter pass up through port and star-
board cable wells to the various decks
radiating from thence to Piaster-switch
and fuse boxes scattered throughout the
vessel, controlling the lamps, motors,
etc.

Disastrous Air Explosions

Violent explosions have on several oc-
casions occurred in air compressors on
the Rand, fume and poisonous gases
descending the air mains to the workmen
below with calamitous results; on one
such occasion over 100 men were
"gassed," some of them fatally. These
explosions, which also occur in other
mining fields, are brought about in the
air cylinders of compressors as the re-
sult of carelessness, the use of too much
oil, or poor qualities of oil, for lubri-
cation in the cylinders, or defective or
leaking delivery valves. Any of these

only results in the ports and valves be-
ing obstructed by a deposit of carbon,
and this is apt to bring about a high
temperature. Air cylinders may be
cleaned by soft soap and water; kerosene
and similar inflammable oils should never
be used for this purpose. A thin oil,
with very little carbon in it, and with
a high flash point is the best lubricant
for the air cylinder. The explosions in
compressors frequently arise from the
breaking or sticking of the air-discharge
valve, which results in some of the hot
compressed air returning to the cylinder,
and the additional heat given to this air
by the recompression is such as to ex-

FiG. 4. Plan ANt) Sections of the Enoine and Turbine Rooms

With the cxccpiion of Fie. 1. the il-
lustrations accompanying this article are
reproduced from The Engineer, of Lon-
don, an 1 much of the information con-
tained herein was derived from the same
source.

may cause the cyllnder-lubricaline oil to
char and the resultine eases to ignite and
explode. Very little lubricating oil is
needed in the air cylinders — less than in
a steam cylinder; good oil in small quan-
tities should be used; an excess of oil

coed the flash and ignition point of the
oil present, which, therefore, vaporizes
and explodes. The ports and valves of
compressors should be periodically in-
spected if accidents are to be avoided.—
Mines and Minerals.

POWER

July 11, 1911

Features of the Leblanc Air Pump

In Fig. 1 is a cross-section of a Le-
blanc jet condenser built for a 10,000-
kilowatt Westinghouse double-flow steam
turbine. The connecting pipe between
the two turbine exhausts is utilized as
part of the condenser and contains the
atmospheric exhaust A, the injection-
water connection B, and the water-spray
nozzles C.

The steam entering through the two
top openings is brought into contact with
the water issuing from the spray noz-
zles and is condensed, the mixture of
water and condensed steam falling
through the large cone into the entrance
of the centrifugal pump which removes
it to the hotwell or cooling tower.

On the right-hand end of the shaft is
located the air pump. This is in a sep-
arate chamber from the centrifugal pump.
The water used in the air pump is taken
from the cold well and may be discharged

rSteam Inlets

By R. N. Ehrhart

This type of pump works
on the principle of entrap-
ping and removing the air
between lamince of water.
At high vacnums it has a
much greater volumetric
efficiency than tJie recipro-
cating pumps.

an entirely new principle is utilized;
namely, the continuous formation of a
succession of water pistons, which act
without the ill effect of restriction through

Centrifugal Discharge Pumps

Fig. 1. Leblanc Jet Condenser in Section and Elevation

back to the same place if desired, as it
is heated less than 1 degree in passing
through the pump. The air is withdrawn
from the condenser through pipe D which
is attached at a point where the condensa-
tion is complete so that no live vapor
is drawn into the air pump. No pre-
cooling is necessary, as the water pass-
ing through it instantly cools the air at
the time of pumping.

Fig. 3 represents a section through
the air pump. Water enters at £, the
revolving annulus of blades F cutting off
the lamin.-e, which are thrown downward
through the dilTuser B and between these
laminations large volumes of air are en-
trained. In commercial operation it is
not unusual to exhaust seven volumes
of air to one of water. This is a strik-
ing result when it is borne in mind that
by the employment of a jet of water in
the most refined type of air ejector or
aspirator, only about 1'.^ cubic feet of
sir are ejected p&r cubic foot of water.
Is this case friction between the water
jet and the air is alone relied upon to
propel the air, while in the Leblanc pump

valves and ports, and the consequent re-
expansion of the air in clearance spaces.
The higher the vacuum maintained with
a Leblanc air pump, the greater its
volumetric efficiency. This is because
the air is removed by the impact of the
lamina; of water, and if the vacuum is
high, the less the mass of air between
the water lamina the more effective the
ejection of the air. On the other hand,
with a reciprocating pump and a high
vacuum, the removal of a certain amount
of air requires the* velocity through the

valves and ports to be a maximum; con-
sequently there is a material loss in vac-
uum caused by friction and wire drawing.
Furthermore, reexpansion in the clear-
ance space and air leakage are most in-
jurious at a high vacuum. Fig. 4 gives the
results of a test of a reciprocating air

Fig. 2. Leblanx Condenser on Testing
Floor

pump compared with that of a Leblanc
pump. This shows that at a high vacuum,
the Leblanc pump is superior; whereas,
at a low vacuum the reciprocating pump
makes the better showing. In other
words, if the power consumptions were
identical the Leblanc pump would be
superior when working in the region
above J3 B and inferior below B B.

Where condensers are used with steam
turbines, an increase of JS inch of vac-

FiG. 3. Section through the Air Pump

uum means a decrease of about 2 per
cent, in the steam consumption and an
equivalent increase in overall economy,
which would almost compensate for the
whole power consumption of the con-
densing apparatus.

In this connection it may be of interest
to refer to some facts brought out in a

July 11, 1911

POWER

49

recent installation of a surface condensing
plant equipped with a Leblanc air pump.
In this particular plant a high vacuum
was desirable as the condensers were
used in conjunction with steam turbines.
The reciprocating air pumps were giving
fairly good results, but were not quite
large enough and it was decided to in-
stall greater air-pumping capacity either
by putting on larger air cylinders, pur-

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1

0

^J

X

R-

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.p

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1

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01 23456789 10
Cubit Feet of Air Removed per Second

Fig. 4. Comparative Air-pump Test
Results

chasing a new reciprocating pump, or
installing a Leblanc air pump.

The Leblanc pump for this work, while
requiring 40 per cent, more power for
its operation than the reciprocating pump,
had a capacity substantially the same as
the reciprocating pump for a vacuum of
approximately 28 inches of mercury, but
with a vacuum of 29 inches its volumetric

the turbine offset the increased power
consumption of the air pump.

A type of Leblanc air pump designed
for marine work is shown in Figs. 5 and
6. The pump is driven by a steam tur-
bine, which is shown at the left-hand
side of Fig. 6.

Colors of Piping
By C. H. Benjamin

Power-plant managers and operators
have given more or less attention to the
identification of piping by colors, but
there are a great number of colors used
and an apparent lack of system. Un-
doubtedly, this has discouraged many
owners and engineers of small plants
from attempting to carry out any such
scheme. In a Varge plant where numerous
auxiliaries of different sorts are in use
in addition to the main units it doubt-
less pays to paint drips, blowoffs, hot-
water returns, etc., but in a small power
house this is hardly necessary.

Where several units are installed a
certain amount of coloring will save both
labor and time. Some engineers are in-
clined to ridicule any such kindergarten
methods as tending to show ignorance on
the part of the employees and claim
that everj' engineer, fireman and helper
ought to know the different pipes without
any such assistance. The same argu-
ment may be used against any color
scheme employed as a means of identi-
fication. In a shop, if the material cards
are pink and the time cards blue, it
does not imply that the employees cannot
distinguish between the two cards with-
out the use of the colors; it merely fur-
nishes an additional means of identifica-
tion ivhich saves time and trouble and
prevents mistakes. Furthermore, in the
piping scheme the use of colors shows
the general layout of the plant at a glance
and makes it easier to keep the arrange-

plication and can be adapted gradually
to the needs of a growing system.

The primary colors should be used for
I'.ie different classes of service, leaving
the shadings and secondary' colors for
minor distinctions. White is used for
high-pressure steam lines as being the
natural color of the protective covering.
If two pressures are used the lower pres-
sure may be painted buff. The use of
superheat on either line can be readily
indicated by a different color of band or
by coloring the edges of the flanges.
Exhaust mains would naturally be
painted drab or black, using the ordi-
nar>' varieties of carbon paint. If there
are two exhaust mains, one leading to
the atmosphere and the other to a con-
denser, the former may be painted black
and the latter a dark drab. Cold- and
hot-water pipes may be painted blue and
red respectively, the colors being from
their nature suggestive of temperature.
In case there are two sources of cold-
water supply two shades of blue can be
used. If there are two different sys-
tems of hot-water piping, one perhaps
being the returns to the boiler and the
other the circulating water of the con-
densing system, two shades of red can
be employed to distinguish these. Green
is used for gas mains because of the
alliteration and different shades may be
used for artificial and natural gas. Yel-
low is about the only primary color re-
maining and this may be applied to air
mains and, as in the cases just men-
tioned, dark and light shades are avail-
able for different pressures or tempera-
tures. There are still left some second-
ary colors such as the browns and the
purples which can he used for refrigera-
tion piping and for drains and drip lines.

The mere indication of live and ex-
haust steam and hot and cold water by
the colors suggested will be sufficient

Figs. 5 and 6. Type of Lebi anc Air Pump, Desicned for Marine Work

capacity proved to be practically three
times that of the reciprocating pump.
The net result was that the Leblanc
pump permitted the maintenance of v^
Inch better vacuum under winter condi-

ment symmetrical and uniform when ad-
ditions or repairs are contemplated. In
fact, it is unnecessary to argue for the
advantage of such coloring; it only re-
mains to suggest how this may be done

in most small plants and further dctailc
can he added as the complexity of the
piping increases. These arc about all
the desirable shades, since all become
more or less dingy with age and too

tions, and the increased economy of without unnecessary expense or com- fine gradations cannot be employed.

50

POWER

July 11, 1911

If still further distinctions are neces-
sary, it is better to make them by color-
ing the edges of the flanges or. by paint-
ing the unions and couplings on the
screwed pipe. For instance, red flanges
on a white steam-pipe line might show
high-pressure steam superheated, the red
suggesting a high temperature, while a
high-pressure water line for hydraulic
service might be distinguished from the
other lines at the same temperature by
blue pipe with red or yellow fittings.

If the system of piping is extremely
complicated, as it is liable to be in a

power house where gas, compressed air
and ammonia are used in addition to the
ordinary media, the painting of white or
jet-blaci< arrows on the piping to indicate
the flow of the fluid is desirable.

Perhaps the best illustration of the
needs of some such system as has been
outlined would be the power plant of a
large hotel or business block in the city
where all of the fluids mentioned are in
common use. Let each superintendent
or engineer begin the coloring on some
such lines as indicated, taking the main
distinctions first and adding the others

gradually as experience dictates and the
advantages will soon become apparent.

There is more or less of a psycho-
logical effect on the employees when
there are such evidences of system and
orderly management as colored piping
indicates. If a boiler or engine room is
in disorder and the eye is confused and
wearied by the lack of system, a little
medicine of this sort has a decidedly
good effect on the employees, very much
as the installation of racks, closets and
pigeonholes for spare parts improves
the morals of the whole working force.

Results of the Boston Anti-Smoke Law

Six months' experience w-ith the en-
forcement of a comprehensive smoke-
abatement law in Boston and several of
the adjacent cities has shown that it is
comparatively easy to decrease a large
portion of the smoke nuisance when the
task is properly undertaken. It shows
also that in a great majority of plants,
more particularly the small ones, the
blame for excessive smoke production
really rests with the engineer. When the
engineer fails to instruct his fireman in
the proper methods of firing, or having
instructed him, neglects to see that his
instructions are carried out, he is not
doing his whole duty to his employer.

A large part of the work in Boston has
been the instruction of engineers and
firemen in the best ways of handling
their particular plants. The smoke in-
spector is W. H. Gerrish, who has had a
long experience with the mechanical and
power end of manufacturing plants. It
has been the policy of the State board
to cooperate, as far as possible, with the
owner and the operating force of every
power plant which offended against the
law. The law itself, as was explained in de-
tail in the April 19, 1910, issue of Power,
is drawn up with scientific precision; it
establishes standards which are tested
by the Ringelmann smoke chart and pro-
vides explicitly for the imposing of
penalties.

In the large plants of Boston the me-
chanical stokers appear to satisfy the re-
quirements of the law, but it is in the
smaller plants that most of the violations
have been encountered. There are, for
instance, about 25 plants which burn wet
wood shavings and which have been very
offensive as smoke producers. The chief
remedy in these cases has been to cut
down the bridgewall practically to a level
with the grate bars. The wet shavings
are generally fed to these furnaces in
an air blast which enters over the fire
doors. Experiments showed that after
being ignited this mixture was deflected
upward by the bridgewall against the
boiler and the cooling which resulted not
only caused smoke but a considerable
loss of fuel value. As the feeding of
shavings in such instances is more or

By Benjamin Baker

This law -d'hich was enacted
last year has not only elim-
inated to a large extent the
smoke nuisance, but also
has aroused among the en-
gineers a keen interest in
the problem of combustion.

less intermittent and the quantity de-
livered varies, some plants have found
it useful to keep the furnace doors open
half an inch or so all the time.

About half a dozen plants in the city
are noteworthy illusfations of the prin-
ciple that the furnace and the fuel must
suit each other in order to obtain good
results. The inspection has disclosed six
Wellington boilers designed for burning
hard coal which have been fed with soft
coal, and the result has been excessive
smoke which it is very difficult to lessen
except by a change of fuel.

Steam jets have proved to be another
prolific source of trouble. If the testi-
mony of engineers and firemen can be
taken at its face value, agents of steam
jets for forced draft have been active
in selling their appliances in Boston, but
have neglected to inform the engineers
and firemen as to the best way of using
them.

One of the important tasks of the
smoke inspector has been to show how
much can be accomplished by a little
careful experimenting, directed by even
a moderate amount of engineering
"horse sense." In a large proportion of
the plants inspected it appears that in
order to avoid undue smoke the coking
method of firing is necessary. The spread-
ing system will also serve, but its weak
points, so far as the human element is
concerned, are well known. Special con-
ditions in some plants have made al-
ternate or side firing desirable.

Naturally, the enactment of a new anti-
smoke law has brought to Boston a flood
of patented devices for preventing smoke,
among which only two seem to have

made any great impression in the way
of practical results. One of these de-
vices consists essentially of a steam jet
suspended in firebrick over the middle
of the furnace and discharging toward
the opening between the bridgewall
and the boiler. It is asserted by
the agents for this device that the dis-
charge steam is decomposed. At any
rate, the position of the jet is marked by
an intense flame and the few plants that
are trying the steam jet are inclined to
look upon it with some favor. It has not
been long enough in use, however, to
show how well it will endure the action
of the furnace heat.

Another method consists essentially of
a dutch oven opening from a transverse
wall tw^o or three feet back of the bridge-
wall. The latter contains an air space
communicating with the ashpit, through
which air is drawn by small steam jets
and discharged by a row of tuyeres so
as to mingle with the smoke and gases
passing over from the fire. The dutch
oven is practically incandescent and com-
pletely consumes the smoke and un-
burned gases which come to it mingled
with the hot air supplied from the
tuyeres.

Aside from the benefit to the general
public resulting from a great lessening
of the smoke nuisance, considerable in-
terest has been aroused among the en-
gineers and firemen. Until lately, the
engineers of the numerous small plants
have not held themselves responsible for
the proper firing of their furnaces. Six
months of the new law has shown that
perhaps 20 per cent, of the firemen do
not care whether they fire well or other-
wise, providing they can hold their jobs.
But the great majority of the firemen
have proved to be merely more or less
ignorant: they have shown an entire will-
ingness to learn how to do their work in
the best way. The engineers have re-
ceived a jolt that in many cases has been
rather severe. The result is that in the
power plants of Boston there is a new
spirit of engineering keenness and re-
sponsibility, and a realization that it is
worth while to get the best possible re-
sults out of a power plant.

July 11, 1911

POWER

51

Efficiency of Rope Drives

At a recent meeting of the Engineers'
Society of Western Pennsylvania, Pro-
fessor Trinks presented a paper upon the
"Efficiency of Rope Drives." It was de-
voted largely to a comparison between
some tests performed at the Carnegie
Technical Schools and those carried out
under the direction of the Society of Ger-
man Engineers.

The German tests were made with
powers up to 200 horsepower, the input
and output being measured by carefully
calibrated electric motors and dynamos.
The rope pull and the influence of cen-
trifugal force were measured by a hydrau-
lic support. Both the English system of
drive — independent ropes in parallel —

to indicate that the continuous-rope drive
is inferior to the parallel drive; but
considering that the sheaves used were
not adaptable to the continuous drive,
the apparent results cannot be accepted
as conclusive.

In comparing these results with those
of the tests at the Carnegie schools,
which are given in Fig. 3, it will be
noted that the results are very similar.
The latter efficiencies were actually
higher than indicated, however, for as
given they include the bending of the
ropes over two additional pulleys and
the bearing friction of these two pul-
leys. Reduced to a basis of the German
tests the Carnegie Technical Schools'
tests show efficiencies over 92 per cent.
The diameters of pulleys were found to

Effect of Soot on Boiler
Performance

Some tests were made recently by
J. J. Coughlin, chief engineer of the
Champion Coated Paper Company, of
Hamilton, O., to determine the relative
effects of clean and soot-covered boiler
tubes. The results are herein tabulated
and present some interesting features.

In every case, with clean tubes, the

Prony Break

60,

.

/tcj.

^■0

FJ:£?-^r-p-

\^1^'
W/^^

\^!OonpTrH,^

1

--

1

20

40

eo

ao

100

Fig. 1. Diagram of Rope Drive in Carnegie Technical Schools

and the American system — one continu-
ous rope — were employed.

In the tests at the Carnegie Technical
Schools a 100-horsepower steam engine
was employed to drive a lineshaft
through a continuous-rope drive and the
power was measured with a prony brake.
The tension of the slack rope was main-
tained constant by exerting a constant
force of 356 pounds on the tension car-
riage. Fig. I is a diagram of the drive.

have direct influence; the smaller the
pulley the lower the efficiency.

Another item investigated by the Ger-
man commission was the influence of an
idler. In this connection it was found
that, with pulleys of 100 and 60 inches
in diameter and a 40-inch idler, the
efficiency of the drive dropped off 10
per cent., due to the presence of the
idler.

Tronsmit+ed Horsepower (Output) '

Fig. 3. Results Obtained at the Car-
negie Schools

temperature of the gases entering the
economizer was lower than with dirty
tubes. This is in line with what would
be expected, showing that more heat was
extracted from the gases with clean
tubes. The stack temperatures were al-
so lower.

It will be noted that in test No. 2
there was no gain from the use of a
soot cleaner when the economizer was in
service. This may seem puzzling at
first, but upon closer inspection it will
be seen that the percentage of CO, was
greater when taking the readings with
dirty tubes than with clean tubes. Hence,
the gain in heat transmission due to
clean tubes was offset by incomplete
combustion in this particular case.

Fig. 2.

100 150 200 E50 300 ^35
ronsmitted Force. Lb per Rope

Results of German Tests

Fig. 2 represents the results of the
German tests. It shows that with only
one rope on the sheaves, efficiencies of
over 97 per cent, were attained, the effi-
ciency remaining high over a wide range
of transmitted power. With several
ropes, however, the range of high clfl-
ciency was very much reduced. Also,
the results of these tests would seem

TF.ST No.

1. COAI.

Test No.

2. Coal

Test No.

3. Coal

Used, Cando Gas,

Used. Cando Gas.

Used.

Kavford

Run of

Mine

Nut and Slack

No. 2

IUn of

Mine

Before

After

Before

After

Before

After

f'leaning

Cleaning

Cleaning

Cleaning

Cleaning

Cleaning

Date of tcsl

Apri. 20

May l.'i

April 2S

.May 13

May 4

May 16

10
14.171

10
14.279

10
14.416

10
14,393

10
14, 4 .-.9

10

Heat vaiuc of coal, B.t.u

14,5.54

0.86

11.7
0.69

12
3.6

12
1.00.5

12
1 .08

11

Moistiirp, per cent

1.89

Average iiK'am pressure, poiinrt!!.

l.iO

\»\

LW

\h\

150

152

Averaee icmniTature of water lo

boiler. diKrces

2.i3

219

2.^(1

226

244

234

Averaee iirniicraliire of water to

167

172

16.i

171

16.1

175

Coal fired, pniiiiils

20,929

18.061

19.30.'.

10.821

19,6.58

1S..500

Water evaporaleil. poiinrls Tor-

reeled to fi-<'d water at Icn d.'iri

181. .128

196.639

189.429

188.598

Kquivali-nl evaporation per pmiiid

of coal wilhoiit economizer.

pounds

9.62

10 76

9 84

10.14

9.88

10 66

Etpiivalenl evaporation per imund

of coal Willi econ<iini7.er. poiind»

10 5

11 36

10.7

10.7

10.68

11 29

Gain from use of economizer. j>er

8 94

8 , 7.')

7 .5

5.6

Averaee l<mperaliire of Kajtc!* lo

eeonomizer. deRrees

669

.'J02

622

490

569

530

Average t. mperaliirc of gases lo

.500
601
200

384
610
20-.
13 64

482
/•.39
180
1.1 08

609
204
12.08

426
603
201
12 6

394

198

Av.r;i!,' ' ' 1,. IH-r cent

12.35

Avcrat" dralt enlerinff econoitllwr.

fJain from ii«e of soot cleaner with-

out I'c^in'imizer. (ler ceni

10 6

2. 9.5

7.3

Gain frfim use of sof»t cleaner with

....

'■*■'

0

5 44

52

POWER

July 11, 1911

The Steam Turbine in Germany

At the outset of this series it was
shown that the scientific treatment of
the problerns which attend the design,
construction and application of steam
turbines, together with the execution of
practical tests, has ultimately defined
those limits within range of which the
different types of turbines have a chance
for further development. Great innova-
tions or revolutionary changes, which
would have an appreciable effect on the
economic ranking of the steam turbine
as a prime mover, are no longer to be ex-
pected. The system becomes a second-
ary consideration as compared with the
constructive usefulness, and the success
of the perfected machine depends more
than ever upon the correct treatment of
the working fluid, the conscientious ela-
boration of details, and the good quality
of materials employed.

The growing number of firms engaged
in the building of steam turbines and

By F. E. Junge

.4 description of the Broun-
Boveri turbine which is a
combination type, employ-
ing the Parsons blading in
the low- and medium-press-
ure elements and a single-
stage wheel in the high-
pressure element. Special
attention is given to the
method of regulation.

bodiment of the now general tendency to
sacrifice specific features to standard
equipment, and to discard old principles
which, at one time, were considered as
fundamental. The replacement of many
high-pressure stages by a single partially

Pure Parsons Type with One Drum

the pressure of competition have in-
duced manufacturers, instead of devoting
their time and capital to new inventions
in that line, to concentrate their best
energies exclusively to standardizing
their output in order to reduce the cost
of manufacture and to increase their
profits. In the manufacture of steam tur-
bines, as in every other line of industry,
it would appear that the selling end of
the business has outgrown the creative
end; that is, the financial forces have
repressed the technical forces of the
concern. Yet it is remarkable that what
is often justly called "unscientific se-
crecy," or the tendency of builders to
surround their shops with impenetrable
walls in order to protect and exploit
specific modes of construction, has been
responsible for much of the progress
which was made by other practitioners of
the art, who were forced to devise new
methods of their own in order to es-
tablish a competency and a profitable
business.

The Brown, Boveri-Parsons steam tur-
bine was introduced and developed on
the European continent by the firm of
Brown, BoveiM & Co., at Mannheim,
Baden. In its latest form it is an em-

impinged high-pressure wheel has many
advantages, resulting in reduced cost of
construction, smaller bulk of machine,
and lower pressures and temperatures
acting on the stuffing boxes and casing,
owing to the wide expansion of the steam
in the high-pressure wheel. From the

decreased below a certain limit. This
condition can be met by reducing the
diameter of the drums. Very short blades
have an unfavorable effect upon the ef-
ficiency. This is due. not so much to the
leakage losses, as to the fact that with
short blades the disturbing influence of
the walls and blade ends on the outer
strata of the steam is more severely felt
than with long blades and a thick stream.
Therefore, the smaller the volume of
steam which flows through the turbine
in a unit of tim.e. the smaller must be
the diameter of the drum. The smaller
the diameter of the drum, however, the
lower the velocity of the blades at a fixed
number of revolutions per minute and
the amount of heat which can be utilized
in one stage is also decreased; further-
more, the number of stages required for
the complete utilization of the total heat
diop becomes greater. When the number
of stages grows to such an extent that
the mechanical loss outweighs the econo-
mic gain, the superiority of the Par-
sens blading reaches its limit.

Under normal conditions this appears
onTy to the high-pressure element. In
the middle and low-pressure elements
the volume of the expanded steam is so
gieat and the blades are so long that the
superiority of the Parsons blading is es-
tablished. But as the high-pressure part
of a purely reaction turbine occupies a
very large portion of its total length,
while the actual service rendered by it
is very small compared to the total out-
put, European builders of Parsons tur-
bines are replacing the high-pressure re-
action part by a single-stage wheel with
two or three rows of blades. Yet they
contend that this "combination type" is
preferably adopted only for special ser-
vices, and that its usefulness depends
upon the plant output, steam pressure.

Fig. 2. Pure Parsons Type with Txso Drums

pureV physical point of view, the su-
periority of the Parsons blading over
other types is defendable as long as the
length of blades does not necessitate the
\\#dth of the annualr steam space being

speed and a variety of other conditions.
They claim that for large units of sev-
eral thousand kilowatts, the employment
of a single stage wheel carries with it no
advantages in heat economy. This is be-

July n, 1911

POWER

53

cause the great mass of steam, even at
high pressures, occupies so large a vol-
ume that the advantage of the Parsons
blading surpasses all others, even in the
high-pressure part.

Fig. 1 shows a Parsons turbine with
one drum, and Fig. 2 the same type with
two drums, which are connected by a

S. <•"

Igl8

1

Ct"

\

\

-— .-..^

t I

§=^12

i 1

£ 10

0 1000 2000 3000 4000 5000 6000
KilowQ+ts "~*"

Fig. 4. Steam Consumption of Combin-
ation Type

movable coupling. The latter is built
for capacities up to about 5000 kilowatts
the division in two parts being made in
order to reduce the distance between
bearings. The combination type as built
by Brown, Boveri & Co. and shown in
Fig. 3 is more representative of modern
tendencies. The idea was to combine all
the well known and tried constructive ad-
vantages of the pure reaction turbine into
one of short length, low cost of manu-
facture, and small bulk, advantages
which attend the employment of a single-

or vibration at critical speeds is rendered
impossible.

This, next to the superior economy, the
makers claim, is the great advantage of
the "combined" Parsons type over those
systems which have only impulse wheels,
and which employ a comparatively thin
shaft and small clearance in order to
keep the leakage losses within reasonable
limits. They contend that in combination
with a reaction turbine, the disadvantages
of the impulse wheel are eliminated and
its advantages fully secured. Having to
transform only a small fraction of the
total energy, the wheel works with mod-
erate steam velocities, whereby undue
wear of the runner is avoided and a
reasonable efficiency is obtained, there
being no leakage loss when a single im-
pulse wheel is employed. Moreover, the
combination turbine can be built so short
that the gain in space makes it possible
to design the reaction part for the most
favorable utilization of the steam and to
make a turbine whose economy is some-
times superior even to the pure Parson's
type. The steam consumption which is
attained with this type at normal loads
with average steam pressure and vacuum
is shown in Fig. 4.

Special care has been taken to im-
prove the system of regulation so as to
obtain the best possible steam consump-
tion at partial loads as well as full load.
This is accomplished by automatic valves
shown in Fig. 3; these open and close
according to the changes of load and reg-
ulate the admission of the steam to the
nozzles almost without throttling. In Fig.
5 is plotted the steam consumption at full
and partial loads.

Fig. 6 shows the turbine-driven oil
pump which is used for starting large
units and for lubricating marine tur-
bines. This pump, at a speed of 4000
revolutions per minute is capable of de-

stant steam consumption for this type of
turbine. In order to secure lasting econ-
omy not only must the efficiency of the
turbine be high, but it must not be re-
duced by wear during operation. When
attempting to build steam turbines with

\ 1

V 1

ZT^tr

_j^£S!

^i. ItHonle

— 1 — . —

0 200 400 600 800 1000 1200
Kilowatts "*"•

Fig. 5. Steam Consumption \(mth
Nozzle Regulation

only a single stage, manufacturers often
overlook the fact that for the energy
transmitted per unit of blade surface
there is a fixed limit which cannot be
exceeded without working harm to the
machine. It is, therefore, objectionable
to assume too small a working surface as
compared to the amount of convertible
energy, just as it is bad practice to make
bearing surfaces and other parts exposed
to friction too small and out of propor-
tion to the pressure and velocity. The re-
duction of turbine proportions by adopting
excessive blade speeds with a view to re-
ducing the cost of construction is al-
ways accompanied by a corresponding
reduction of the total working surface of
the runners, whereby the limit is often
reached if not exceeded. The inevitable
result is a perodical replacing of the
runners, when the increasing steam con-

Steam Entrance

Oil under ^?r^T -^
.Pressure ; J^. '

Fir,. 3. Brovin-Boveri Combination Type

Fig. 6. Oil Pump

stage wheel. The latter is mounted on
the front of the drum and constitutes a
rigid runner, with a short distanse be-
tween the bearings and ample play at
all places, whereby friction between the
runner and the cylinder through bending.

livering !^2.H gallons of oil per minute
a! 22 pounds pressure. It is driven di-
rectly by an impulse wheel having two
rows nf bl.ides.

Among the special claims of the Brown,

sumption becomes objectionable. By the
employment of surface condensers which
deliver clean steam to (he turbine this
drawback Is partly nullined.

Fig. 7 shows a comparison between the

Boveri & Co,, are small wear and con- cfTactive blade surface of an impulse tur-

54

bine having ten stages and of a Parsons
turbine of seventy stages. The differ-
ence explains, on the one hand, why
Brown, Boveri & Co. continue to em-
body, as far as possible, the Parsons

Fig. 7. Comparison of Blade Surface

principle in their new designs, and why,
on the other hand, certain types of single-
stage pressure turbines, representing the
other extreme, are disappearing from the
market owing to rapid wear.

Another feature claimed for the Brown,
Boveri turbines is that they may be
brought up to full load immediately and
are practically immune from wide tem-
perature fluctuations. This latter feature is
attained by symmetrical proportioning of
the cylinder, by the arrangement of the
low-pressure balance piston on the ex-
haust side and by avoiding widely di-
verging diameters, whereby the equal
\v arming up of all parts is secured, also
the high-pressure shaft journal is pro-
vided with an internal heating chamber.
The blades in the reaction part of the
turbine, instead of being merely chiseled
ir;to the groove are secured by means
of heads, thus providing for expansion at
varying temperatures (see Fig. 8). The
impulse wheels of the combination type
are shown in Fig. 9, the blades being

POWER

is dependent upon the available steam
pressure. Therefore, a new mode of
regulation was developed in which the
governing piston, instead of being actu-
ated by the steam, is controlled by the
oil pressure in the lubrication system.
Among the advantages of this system, is
that should the lubrication become de-
fective the turbine is brought to a stand-
still. The governing device consists of
two separate parts, shown in Figs. 10
and 11. These are connected only by an
oil pipe. The governing device proper
(Fig. 10) is mounted on cover B of the
collar thrust bearing, and comprises the
casing A, which is divided in two parts
surrounded by mantle C. Shaft D of the
governor is driven by a worm gear from

^T•1

July II, 1911

sifion of the regulating socket K. Th=
oil passing through this slot enters
through box L into the casing M and
from there drops onto the governor, lu-
bricating its journals and joints as we!i

I — I trrf

Fic. 8. Attachment of Blades

made of a special bronze, inserted and
held in place by distance pieces.

Regulation
The old type of Parsons turbine with
steam-pressure relays gives satisfactory
results in practice and has the disadvant-
age that regulation within certain limits

Fig. 9. Impulse Wheels of Impulse
Type

the turbine shaft £ and turns within the
bearings F and G, the latter a thrust
bearing. On shaft D is fastened the
safety governor H and the main governor
J, which is connected with socket K and
revolves within the fixed box L. The
regulating socket moves in an axial di-
rection on shaft D, its position depending
upon the position of the governor weights.
Box L is surrounded by a casing M, and,
in its lower parr, has an annular channel
connecting the governing device with the
piston O, Fig. 11, of the steam-inlet valve
by means of the flanged socket N and
the oil pipe T. The piston is fastened to
stem P of the steam-inlet valve Q. ' From
the oil pump R a certain quantity of oil
under pressure enters through pipe S
below the oil piston O and thence
through pipe T into the annular space of
the casing M. In box L is a slot connect-
ing with the annular space whose open
cross-section depends upon the axial po-

Fic. 10. Main Governing Device

as the bearings of shaft D, whence it
returns to the oil tank.

The action of the oil regulation is as

Fig. 11. Steam-inlet Valve

follows: Through flange U on the valve
chest V. the steam enters and passes in
succession valve W, sieve S, and valve Q.
The lift of the steam-inlet valve is de-
termined by the oil pressure under piston
O acting against the pressure of the spring,
regulation being effected by the gover-

July II. 1911

POWER

55

nor according to the momentary load. By
undulating the edge of socket K the open
cross-section of the slot in box L is con-
stantly varied during one rotation of the
regulating shaft. This allows a continu-
ous increasing and decreasing flow of oil,
and causes a corresponding vibratory
motion of the oil piston. The pulsations
occur in rapid succession, from 300 to

Fig. 12. Auxiliary Valve for Parsons'
Type

700 per minute, and cause only small
pressure variations of the steam. Thus
both the axial and the rotary motion of
the socket are utilized for purposes of
regulation, the former for the main and
the latter for the secondary effects, the
sensitiveness of the governing device be-
ing thereby materially increased. In
cases of over regulation the cone below
piston O serves to increase the open
cross-section of th: oil bypass, tending to
return the piston into its mean oscillating
position. In cases of under regulation
the same effect is attained by the op-
posite means.

By turning wheel A,, the regulating
socket is either lifted or lowered, and
the open cross-section of the slot is
changed and the resulting change of the
oil pressure effects a corresponding
change in the position of the inlet valve;
this produces an increase or decrease in
the number of revolutions, providing the
load on the turbine remains the same.
With a given speed the load can be varied
in a like manner, the range of variation
being plus or minus 5 per cent. Instead
of using wheel /4,, the same operation can
be performed from the switchboard by
means of a magnetic relay. An adjust-
able oil brake S, takes up sudden shocks
Which might occur in the regulation.
When the speed of the turbine exceeds
■ certain limit the safety governor H,
by means of shaft X and the connecting
link, turns the key V. and the main inlet
valve W is closed by the pressure of the
•pring. The same result can be attained
by a hand lever, and in order to reopen
the valve again the handwhcci must be
used.

In order to avoid uneconomical ihrof-
ding and to utilize all of the available
■team pressure at the various loads

these turbines are equipped with one or
more automatic auxiliary valves. In the
pure Parsons type the valve admits steam
into a chamber of larger section, (see
Fig. 12 1, whereas, in the Brown-Boveri
tjpe it opens another series of nozzles,
shown in Fig. 13. In the former type
the valve opens if the increasing pres-
sure in space /, together with the pres-
sure of spring F exceeds the force with
which the constant boiler pressure acts
on piston K. By sdjusting spring F the
range of operation of the valve can be
varied at will. The opening and closing
are performed without any evil effect
on the regulation, and the automatic
valve avoids the necessity of additional
hand regulation of the nozzles.

The Brown, Boveri turbogenerators
are equipped with four bearings and the
shafts of the separate units are con-
nected by a movable coupling. Turbines
running at 1500, and less, revolutions
per minute are equipped with ball-shaped
bushings lined with white metal, and
self adjusting. For higher speeds the
regular Parsons type of bearing is em-
ployed consisting of a number of eccen-
tric boxes which can be so turned as to
permit an exact adjustment of the shaft.
The small clearance in the box is filled
with oil under pressure in order to equa-
lize possible vibrations. The working sur-
faces are made amply large for the sur-

FiG. 13. Auxiliary Valve for Combina-
tion Type

face pressure, so that even after several
years of continuous operation the bear-
ings show no trace of wear. The only
movable part of the Brown, Boveri tur-
bine which is not under the influence of
the central lubrication is the steam-inlet
valve. Owing to its vertical position,
however, this is subjected to little wear.
Considering the low class of attendance
with which some plants in foreign coun-
tries have to reckon, and in view of the
fact that, as a rule, they are far from
repair shops and have to guard against
sudden breakdowns, it is obvious that re-

liability is a decisive factor, enabling one
to reduce the number of reserve units
to a minimum, and also to keep the num-
ber of interchangeable parts relatively
small.

The employment of the Parsons blad-
ing and of drums instead of thin shafts,
v.hereby the operating speed is kept far
below the critical speed, does away with
the necessity for internal guides and
packing boxes, which might also neces-
sitate the introduction of lubricants into
the turbine. Likewise, the employment
of labyrinth packing permits free play
of the shaft in an axial direction and
avoids the use of lubricants in the boxes.
Special care has been taken by the build-
ers to provide accessibility to the inter-
nal parts. By lifting the upper half of
the cylinder the whole drum is exposed
and the guides and runners can be in-
spected without having to remove sepa-
rating walls. The bearings also can be
easily uncovered. All movable parts of
the regulating system are contained in
cssing A. and the mantle C can be re-
moved by unscrewing a few bolts. The
oil pump which is attached to the lower
end of the regulating shaft can be taken
out and inspected by opening the cover
below it, and without having to dismount
the governing device.

The W orld's Largest Crane

According to Consul J. N. McCunn, of
Glasgow, there has been erected at
Govan, on the River Clyde, for the Fair-
field shipyards, the largest crane in
existence. The official trials of this inam-
moth appliance have been satisfactory
and it stands in bold relief on the River
Clyde, where a number of the most
powerful cranes in the world had pre-
viously been erected.

The jibhead of the crane is of the
hammer-head type, built on the cantilever
principle, and stands 160 feet above high-
water level, or to rail level 169 feet. The
jib, with a total length of 270 feet, ex-
tends 1 69' J feet outward from the cen-
ter and can be utilized within every point
of a circle 336 feet in diameter. The
motors for operating the gear vary from
60 to 90 horsepower, and are situated in
the machinery house at the rear end of
the crane, the test load of which is 250
tons.

The crane, on slow gear, can elevate
200 tons extended 1F< feet along the jib,
and on quick gear it can manipulate a
load of 100 tons at 133 feet. The maxi-
mum load of 200 tons can be lifted from
30 feet below wharf level to 140 feet
above, a total of 170 feet. The three con-
trolling brakes are worked by magnetic,
mechanical and hydraulic action. The
stability of the structure of the crane
depends on four huge steel cylinders, one
under each corner of the tower. These
great tubes, I.S feet in diameter at their
base, are filled with concrete and sunk
74 feet below ground.

POWER

July 11, 1911

Intake Manifolds for Multi-
cylinder Engines

By John S. Leese

Discussing Mr. Hall's engine in the
April 25 number, B. M. Howze gave a
sketch of a symmetrical intake manifold,

Fig. 1. Symmetrical Intake Manifold
Given by Mr. Howze

reproduced here as Fig. 1, and said that
the intake piping should be arranged as
shown in that sketch.

Although from the point of view of
mechanical symmetry Mr. Howze's pip-
ing is perfection, I should like to point
out that in order to get the mixture to
the cylinders, at least five right-angle
turns in various planes have to be passed
and six if the carbureter flange faces
12 3 4

Fic. 2

horizontally. I believe that it would be
better on all counts if builders would
go to the trouble of either designing their
piping as shown in Fig. 2, with easy
sweeps from the carbureter to the cyl-
inders and suitably proportioficd to
Insure an equal supply of gas to all
cylinders, or as shown in Fig. 3, in which
case the equality of supply could be as-
I E 3 4

Everything'
worth while in thega^
engine and producer
industry will be treated
here in a way that can
he of use to practi-
cal men

difficulty when the gas is supplied at
one end of a manifold by casting their
manifolds as shown in Fig. 4. The order
of firing is 1, 3, 4, 2, so that Nos. 1 and

Fig. 3

sured either by increasing the diameter
of the pipe, as indicated in the sketch, or
by casting or fitting two bores in the
manifold, one supplying two cylinders,
one on the right-hand and the other on
the left-hand side.

Some makers of multicylinder gas en-
gines have got over the unequal-supply

.■60s. ISc4

■EEB

-A irZ &3
-A Ir I 8c4

Gas Ea.3
Flarxje to which Throttle Valve Casing n bolted

I y : '

\

_-

1

1

1

:: ;;

\

2

!

■

'-

1 " ;i

: fc' ■ :

3

■ 1

1 1 1 1 1

1 1 p. 1 I

;

\-

4

',' 'q i I

1

H

Air Oas

1 *

Air 6<7S

ptPi

Air Gab

^-i--

Air Gas

1 L

flange is fed from the passage on that
side; that is, from the side of the light
shading.

Fig. 5 is a set of accurate tracings of
indicator diagrams taken from a four-
cylinder vertical engine fed by a mani-
fold like that in Fig. 4 and there can

NO./ Cylinder

Fig. 4. Partitioned Manifold for Uni-
form Distribution

4 and Nos. 2 and 3 do not require their
mixture consecutively. The light shading
in the flange orifices is intended to con-
vey the impression that that particular

Fic. 5. Diagrams from Engine Equipped
with the Manifold in Fig. 4

be no cause for complaint ibout their
nonuniformity. All valve timings, spark
adjustments, etc., are exactly alike on
this engine and the cylinder heads and
combustion chambers are machined all
over so that equal volumes are assured.

July II, 191 1

PO^X^ER

57

Correcting Back Firing and
Fuel Waste in a Large
Producer Gas En-
gine Plant*
By John G. Callan

A short time ago the writer, with some
associates, had occasion to test a large
producer-gas engine plant in order to
determine whether or not the plant met
guarantees as to average and maximum
output and fuel efficiency, and every ef-
fort was made to put the machinery in
the best of condition and to obtain the
best possible performance. It is not
the purpose of this paper to report the
entire test, which occupied the greater
part of a month, but rather to point out
some specific items wherein it was pos-
sible to improve performance, and to
briefly analyze the more important of
these. Since, in spite of best endeavors,
it was not possible to bring the apparatus
up to guarantee I omit any specific refer-
ences by which the plant would be
readily identified.

The installation consisted of single
tandem double-acting producer-gas en-
gines with 33x48-inch cylinders, driving
three-phase 25-cycle alternators at 107
revolutions per minute. The alternators
operated in parallel and delivered power
to an industrial plant furnishing a sub-
stantially steady load, and to some other
minor users.

Gas was furnished by producers of a
well known type. From their individual
wet scrubbers the gas passed through a
common dry scrubber to a 30,000 cubic
foot holder and thence to the distributing
main leading to the engines. The fuel
was lignite of about 7600 B.t.u., contain-
ing about 34 per cent, moisture and 8
per cent. ash. The gas averaged about
105 B.t.u., high thermal value. In mak-
ing our tests the mill load was adjusted
to suit the engine output and there was
always available as much load as the
engines could carry.

The plant had been installed by the
manufacturers and shortly after its in-
stallation the designer of the engines had
spent a great deal of time in bringing it
up to the best possible performance.
Subsequent to this, the operating engi-
neer of the station had continued running
the plant along the lines which had been
fixed upon by the designer and he ob-
tained slightly better results from the
engines, and also somewhat improved
producer performance. The results were
Still very far from satisfactory, however.

We found that the engines had given
much trouble with back-firing and some
with premature ignition. The back-firing
had been so serious that it had been
deemed necessary to put throttles in the

•Ahsfrnrt of n pnpT prpn«'nl'»»l Itpforn fhp
rnnerpuB of Tcrhnolnev nt tho nftlpth nnnl-
TPDiiirT of lhr> ernnilnB of Itio rlinrKT of the
UiiKfuirhiificttii Inntlliitc of Tprlinnlotty.

air lines and cut down the air supply
to a point below that at which the rate
of propagation of the flame in the mix-
ture was a maximum. As is well known,
this expedient, though wasteful of gas,
is usually effective in stopping back-firing
and it was so in this case.

We were told that the designer of the
engines directed that they should be ad-
justed to give "round-top" diagrams and
indicator diagrams which we took showed
that these instructions had been observed.
This shape of diagram is obtained by
timing the ignition so that it is not early
enough to bring about substantially com-
plete combustion during the period of
very slight motion near the dead center.*
The exact timing of ignition to give this
or any other shape of diagram naturally
depends on many factors, the principal
ones being compression; composition and
homogeneity of mixture; shape of com-
bustion space and location of spark
plugs; temperature [ ?] and character of
spark. The ignition points of the dif-
ferent engine cylinders in the plant un-
der discussion differed somewhat and
had been determined empirically as giv-
ing the desired diagram with the rich
mixture deemed necessary to prevent
back-firing.

This practice led, as late ignition is
likely to do, to a magnification of the un-
avoidable differences between successive
diagrams, so that a "card" consisting of
twenty successive diagrams with one un-
changed governor and mixture setting
showed a very large range of contours.
We were assured by the attendants, how-
ever, that if the mixture giving best
maximum diagram were employed, the
back-firing would recommence and in
time become prohibitive. Tentative ex-
periments seemed to confirm this and it
therefore became necessary to determine
the reason for this back-firing.

Back-firing is most likely to occur from
ignition of the incoming combustible mix-
ture at the inlet valve. In a double-
acting engine it may also be caused by
leakage of hot gases from the explosion
in one end past the rings and into the
other end where the suction stroke has
just been completed. It may also occur
from a lingering flame in an indicator
fitting or from red-hot carbon or ex-
tremely hot metal parts so placed as to
pocket gas between two heated surfaces.

If the back-firing is due to escape of
flame past the piston rings it can occur
in only one of the ends of a given cylin-
der on a four-stroke double-acting en-
gine. For instance, if the cam setting is
such that combustion is occurring in the
crank end just as suction is finished in
the corresponding head end, there may be
preignition from this source in that head
end but, since the cycle is never re-
versed, it can never occur in that crank

•A moro rnllonni mcthotl. ntilrli \n ii«iinlly
Pmploypfl hv PTiiorlcnrprl pnglnppr*t. \n lo 11.10
n rfltitipr "Ipnn" mlxtiirp nni\ Inrrpniw**! ncl-
VBiirp of lifnillon llmtnK. -Knixnii.

end. Since one of the most obstinate
cases of back-firing of which the writer
had known was due to this cause the
matter was carefully investigated. It was
found that preignition occurred in the
crank ends and head ends indiscriminate-
ly, so that blowing through the rings was
certainly not the only source even if it
was an occasional one.

The indicator fittings not already so
made were changed to a type which
closed off practically flush with the inner
surface of the cylinder wall and it was
at first thought that this effected an im-
provement, but back-firing developed
again, proving that it was merely chance
which caused its diminution when the
new fittings were put on. This led to
the inevitable conclusion that the trouble
was ignition of the incoming gas either
by the outgoing exhaust or by heated
parts of the cylinder, or both.

The design of the engine differed from
that of most American tandem double-
acting gas engines in that the valves oc-
cupied a valve chamber connected by a
relatively narrow neck with the main
clearance of the cylinder. The exhaust
valve was in the bottom and the inlet
valve in the top of this chamber and they
were separated from each other by a
distance of only about ten inches.

The valve setting w^as such that the
inlet opened before the exhaust closed.
The amount of lap was different on dif-
ferent cylinders, due to slight wear of
the cams and rollers, and it could be con-
trolled to some extent by adjusting the
amount of clearance between the valve
rocker-arms and the stems, but with no
normal adjustment which did not entail
serious shock was there a complete
closure of the exhaust port before the
inlet valve opened. This suggested the
idea that the slight back pressure pre-
sumably existing in the cylinders might
force a little of the hot exhaust gas past
the slightly opened inlet valve and ignite
the mixture. This seemed highly im-
probable, however, on account of the
cooling action on the gases which would
result from intimate contact with the
water-cooled inlet-valve seat and the
valve which had just risen from it.

By diagrams and other means we en-
deavored 10 determine whether the back-
firing took place at the end of the stroke
or at some intermediate time and con-
cluded that it was at the beginning, and
for the time we fell back on the hypothe-
sis that the heated valve chamber caused
ignition of the combustible mixture dur-
ing the early part of the inlet stroke.

Finally we took stop diagrams with a
light spring and full diagrams with the
ordinary spring, but with the back-lash
in the indicator motion. These showed
unforeseen conditions during exhaust and
led to the tnic solution. It was found
that the pressure in the cylinder immedi-
ately after the opening of the exhaust
valve was above atmospheric, as might

58

POWER

July 11, 1911

be expected, and that it remained there
for a certain fraction of the exhaust
stroke. For the remainder of the exhaust
stroke, however, the proportion varying
with load and cylinder from the last
two-thirds to the last half of the exhaust
stroke, there was a very slight vacuum
in the cylinder instead of the positive
back pressure which had been expected.
This was found to be due to the wave
set up in the long straight exhaust pipe
by the first vigorous puff at release.

From this it immediately became clear
that on the opening of the inlet valve
explosive mixture began at once to enter
the valve chamber, even though the pis-
ton had not yet finished its exhaust
stroke, and that this inflow became more
and more vigorous as the valve opened
farther, the incoming mixture mingling
with the outgoing exhaust gases and in
part passing out with them through the
exhaust port. This explanation of the
back-firing was entirely rational. We did
not have to assume that the exhaust
gases were hot enough to pass through
a slightly open, relatively cool port and
still retain the temperature required to
ignite explosive mixture, nor did we have
to assume walls so hot that a rapidly
whirling and eddying blast of incoming
mixture impinging upon them was there-
by ignited.

It was then assumed that a large num-
ber of incipient ignitions took place which
did not propagate fast enough backward
along the incoming gas stream to reach
the mixing chamber and were blow-n out
as the velocity of induction increased.
Accepting this hypothesis and also recog-
nizing the fact that a perfect mixture
fires more easily and propagates flame
faster than others, it was apparent why
a rich slow-burning mixture prevented
most of the trouble.

It was all along recognized that the
use of an unduly rich mixture besides
being wasteful was objectionable because
ii increased the luminosity of the flame
and hence the radiation, besides coating
the interior of the cylinder with a car-
bon deposit which tended to reduce the
efficiency of the water jacket and to in-
crease the skin temperature of the in-
terior of the valve chamber.

While this m.atter was being analytical-
ly investigated a series of diagrams had
been taken running with various mixtures
and ignition settings and it had been
decided that on account of the extremely
heavy reciprocating parts the maximum
stresses on the journals would not be
greater with pointed than with round-top
diagrams, since apparently the largest
component in maximum journal pressure
was that due to inertia rather than that
due to the explosion. This last con-
clusion was borne out by the fact that
the bearings ran much hotter on no load
than on full load.

On account of the apprehensions of
the station attendants these experimental

settings were not at first maintained very
long, but since they bore out the con-
clusions just mentioned, we finally
changed the operation of all the engines
as to both the mixture and the ignition
settings. The mixture was adjusted for
a slight excess of air over theoretical re-
quirements and the ignition was timed
materially earlier, producing a pointed
rather than a round-top diagram and ma-
terially reducing the temperature of the
gas at the moment of release when the
explosive mixture mingled with it. After
these changes were made the marked
improvement in operation became so ap-
parent as to convert even the more
skeptical of the station men. Back-firing
was not wholly eliminated, occurring oc-
casionally in all cylinders and particular-
ly in certain ones, despite the changes,
but the improvement was distinctly
greater than we had expected. The
changes also enabled us to increase the
engine output and to materially cut down
the amount of gas used per kilowatt-
hour. The reduction in fuel consumption
was so marked that it was not merely ob-
servable by the methods of the test but
was noticed by the producer men during
a period when the engines were carry-
ing considerably more load than was
previously customary.

It was interesting to note that some
analyses of the exhaust gas showed that
if samples were taken as usual from a
point a few feet below the top of the
exhaust pipe, the analysis indicated a
rather large excess of air in the mixture
at a time when it was practically certain
that such an excess did not exist This
might easily have misled previous ob-
servers and was, of course, due to the
regurgitation of air into the exhaust pipe
during the recession of the wave set up
in the pipe by the "puff" occurring at
release, as well as the loss of combustible
mixture into the exhaust.

Gas Producer Investigations b}'

the United States Bureau

of Mines

At the Pittsburg fuel-testing station of
the Bureau of Mines an experimental gas
producer has been installed for the pur-
pose of studying the processes which go
on in producers and to investigate the
feasibility of slagging the ash by the ad-
dition of a flux so as to remove the non-
combustibles in the form of liquid slag.

The outfit includes a small steam
boiler and a positive blower, by means
of which it can be operated as a pressure
producer.

The blast is introduced through water-
cooled tuyeres located near the bottom
of the generator; steam is admitted
through separate tuyeres which are lo-
cated in a plane one foot above the air
tuyeres; fuel is charged through a hop-
per at the top, and at the bottom of the

generator provision is made for the re-
moval of liquid slag as it forms.

Tests to investigate the effect of slag-
ging the ash, both as to economy and
deterioration of the producer lining, are
now in progress. Subsequent tests are
planned to study the effect of varying
the fuel-bed thickness, the ratio of air to
steam, the rate of combustion, the size of
coal and the preheating of the air. It
is considered desirable to make these
tests first with as nearly an elementary
fuel as possible; therefore, coke is being
used. Other fuels will be used later.

In tests already made, it has been
found that the ash can be made to slag
readily and that the slag will run freely
from the producer. The best results,
thus far, have been obtained when ap-
proximately 15 pounds of limestone
were charged per 100 pounds of coke,
but of course this ratio will vary accord-
ing to the chemical analysis of the coke,
the ash and the limestone. In one test
of over 75 hours' duration, the slag was
tapped off about once an hour with very
satisfactory results as far as the slag
was concerned, but by the end of this
run the generator lining had suffered
severe deterioration. The temperatures
necessary for the formation of liquid
slag are very favorable for the produc-
tion of gas and in the tests already made
the CO has generally been above 30 per
cent., while the CO; has been well under
2 per cent. These percentages, how-
ever, were obtained with air alone, no
steam being used.

The high rate of combustion also in-
creases very materially the capacity of
the producer; frequently, 2000 to 2500
cubic feet of gas per square foot of fuel
bed per hour have been produced, having
a heat value of about 115 B.t.u. per
cubic foot, thus giving an output of ap-
proximately 25 horsepower per square
foot of fuel-bed area. Up to the time
of the recent A. S. M. E. meeting in
Pittsburg, no attempt had been made to
operate the producer at its maximum
rate.

Fuel briquets from street rubbish,
states a contemporary, have been ex-
perimented with at Amsterdam, Holland.
Hitherto the rubbish has been assorted
and the paper, rags, metals and glass
sold to dealers. The city authorities are
now considering converting the street
sweepings into combustible briquets for
heating boilers. In Southwark, London,
the refuse is crushed to a powder and
sold as manure, .^t St. Ouen. France,
the powder thus made, with the addition
of combustible substances, is converted
into a cheap fuel. At .Amsterdam, ex-
periments were made in combining the
pulverized rubbish with coal tar from
the gas works and pressing into briquets;
the results are said to have been suc-
cessful. The quantity of material avail-
able is about 140,000 tons yearly

July 11, 1911

POWER

59

AnnualConventionA.I.E.E.atChicago

The twenty-eighth annual convention
of the Institute, held in Chicago, was
opened on Tuesday morning, June 27,
with several hundred delegates actually
in the hall. After the usual preliminaries.
President D. C. Jackson delivered his
address in which he departed widely
.from the beaten track of presidential
addresses to im.press upon his hearers
their ethical obligation to society at
large in the direction of properly con-
trolling the potent factors in civiliza-
tion which they themselves have been
the means of crealing. That part of his
homily was particularly graceful and well
founded and it is tc be regretted that he
almost spoiled the effect of it by wind-
ing up his address with a barefaced ad-
vocacy of the cause of public-service
corporations and an exhortation to the
engineers to stir themselves with a view
to educating the public into "recognition"
cf the "rights" of such corporations.

Presidcnt-elsct Gano Dunn was then
introduced and acknowledged his intro-
duction in a most modest but none the
less forceful acceptance of the responsi-
bilities as well as the honors of the of-
fice to which he has been elected.

Power-limiting Reactan'ces in Large
Stations
The first paper read at the convention
was one by R. F. Schuchardt and E. O.
Schweitzer, of the Commonwealth (Chi-
cego) Edison Company, on the use of
power-limiting reactances with large
tiTbo-alternators. The troubles of the
early alternating-current stations con-
taining slow-speed alternators driven by
ixciprocating engines are quite well
known, and were comparatively simple
in the light of modern practice. When
high-speed turbo-alternators were intro-
duced, however, new and serious troubles
developed which indicated that these
units had characteristics quite different
II om those of the older ones. The ex-
ricnce of the Chicago Edison Company
'ing the past eight years has shown
increasing severity in disturbances
I line troubles with the increase in sta-
-!-generator capacity.
The four original 5000-kiIowatt al-
■nators at FisK street had their neutrals
■undcd solidly. These were all 9000-
t machines running at 500 revolutions
r minute. When a fifth unit was in-
illed, of larger capacity and running
higher speed, it was found that when
neutral of this unit was connected
the ground, a heavy cross-current
vcd between if and the other units and
resistance of about 2'A ohms had to
installed in the neutral connection,
additional units were also provided
•h neutral resistances and later the
J neutral groii'id connections of the
r original units were removed.

Disturbances were, however, still suf-
ficiently severe to be seriously trouble-
some and the system wa'= therefore
divided into sections so that when a
fault occurred it could be limited to the
section in which it was located. Even
with this precaution severe disturbances
occur, some of which develop in the gen-
erator armatures themselves. In the
four years from 1906 to 1909 inclusive
there were seven generator burnouts and
in all of these cases the projecting ends
of the ar.aiature windings were torn loose
and the windings wrecked. This led to
niore rigid construction of the generators
and the use of a new form of armature
winding with a stronger arrangement of
end projections and with one coil per
slot instead of two. This improvement
was efficacious but with severe short-
circuits the circuit-breaker switches gave
considerable trouble and in some in-
stances failed. This showed the neces-
sity for limiting, by means of added re-
actances, the current which can flow into
a defective circuit. The transformers
were rewound so as to make their in-
ternal reactance higher and new gen-
erating units were also constructed with
higher internal reactance. Additional re-
actances, external to the apparatus men-
tioned, were provided in series with the
primary leads of the transformers, which
operate at 9000 volts. These have been
in service nearly two years, during which
time the transformers have withstood a
number of short-circuits of a kind which
had previously wrecked them.

In the case of the generators the in-
stallation of reactances was a far more
serious problem and in view of the large
investment required, as well as in order
to proceed more intelligently, it was de-
cided t& determine by exhaustive tests
the exact effects of added reactances in
the circuit. For this purpose one of the
12,000-kilowatt units at the Fisk Street
station was usjd. Tests were made with
this unit to deteimine the instantaneous
shrirt-circuit current of the generator
without any external reactance; the in-
stanfflncous short-circuit current with an
external reactance of 4 per cent.; the in-
stantaneous short-circuit current with an
external reactance of 6 per cent.; the
duration of transient phenomena incident
to the short-circuits; the effect of the
short-circuit currents on the generator;
the behavior of the reactance coils, and
the effect of these coils on the stability
of the system.

A set of three icactance coils, one for
each phase, was used. Each coil had 76
turns of cable wound on a hollow con-
crete core about three feet in diameter.
The cable had a cross-section of 1,000,-
000 circular biMb. The impedance of
each coil at 2h cycles measured 0.425 of

an ohm and the resistance measured
0.0075 of an ohm. The tests were made
by short-circuiting the generator while
it was running at full speed and with the
neutral connection solidly grounded ex-
•cept in one or two instances, when a
resistance of 2,'j ohms was inserted in
the neutral connection.

With the generator excited to give 3000
volts the maximum current obtained with-
out any reactance in circuit was 9800
amperes, and at 4000 volts it went up to
13,000 amperes. Assuming this propor-
tionality to hold all the way up to normal
voltage, the maximum current at the nor-
mal pressure of 9000 volts would be
about 29,000 amperes, or 27 times the
full-load current of the machine. With
the 4 per cent, reactance in circuit, which
would take up 208 volts at 25 cycles and
full-load current, the current values ob-
tained were such as to indicate that at
the normal voltage ef 9000 the short-
circuit current would have been about
18,000 amperes, and with an external re-
actance of 6 per cent., which would
take up 328 volts with full-load current,
the short-circuit current at 9000 volts
was 15,800 amperes or 14iJ times the
full-load current.

Extensive precautions were made to
determine the effect upon the generator
and the reactance coils of the short-
tircuit currents, but there were apparent-
ly none; no displacement or indications
of damage or distortion could be de-
tected.

The tests indicate that the instantane-
ous short-circuit current of the generator
on which they were made is nor as high
as has been thought but they also in-
dicate that this current, on account of
its comparatively high power factor, can
produce severs stresses on the generator
and the oil switches. They also indicate
that the use of such reactances will tend
to make the operation of the system as
a whole more stable and therefore to
increase the liability of service.

When the tests described in the paper
of Messrs. Schuchardt and Schweitzer
were made, the behavior of the oil cir-
cuit-breakers employed was also watched
very carefully and in a short paper by
B. B. Merriam the results of the tests
on the circuit-breakers were described.

Whenever an electrical circuit carry-
ing a large amount of energy is open
under oil, gases are generated and these,
of course, expand and tend to force the
oil out of the containing vessel. Oil
switches have been blown up and totally
wrecked by the gases thus formed by the
arc between their contacts, but the
switches used in these tests did not show
any di.'ircss from this cause. They were
the ordinary type of oil circuit-breakers
operated by solenoids, but there had been

60

POWER

July 11, 1911

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July 11, 1911

POWER

M. H. Collbohm considered the use
of reactances for reducing short-circuit
current to be a mal;eshift; he disapproved
of impairing the regulation of a syn-
chronous generator for that purpose and
thought that the use of the induction gen-
erator would be much better. A station
equipped with such generators and con-
taining synchronous motors running idle
to supply the exciting current he thought
would be entirely feasible. Stations thus
equipped would operate more smoothly
in parallel and a water-power station of
this type could be readily operated in
parallel with a steam station probably
without the use of hydraulic governors.
and thereby utilize the full energy of
the stream under all conditions.

D. 3. Rushmore said that if the in-
ternal reactance of a generator were in-
creased it would gieatly increase the dif-

TABLn; I. COST Or COX.STRICTIO.N
Poicfr Stations:

BuililinR. slacks, coal- and

a-sh-handling macbmerv . S.'?54.00O
Equipment 640.900

Total 8994,900

Transmission line 241,500

Svbtlolion^:

Builriin?3 72.000

Equipment 419.560

Total 491..i60

Third rail 557.6.36

Overhead trolley 80.500

Track bonding 102.659

Cars 1.135,900

Car-repair and inspection

shi-ds 46.674

-iiiof-wav. additional.. . . 592.100

"isiructing tracks 76.3.800

•ructin? new tracks .... 2,071,000
ninal lacilities and

changes at stations 252,400

Signals and interlocking

plants 561,900

ClijiiL-iiii; lolegraph and add-

I'lne facilities.. . . 105.100
j'lt-of-way, cattle

8S,4no

• 1.S items 44.200

lolal «8. 1.30.229

U.NIT COST OF ELECTRIFICATIO.N

- • ■•■nn, cost per kilowatt SI 10 00

n line, cost per mile . . 3,485 00

. building and equipment

r lowatt 28.90

.1... ^ust per mile 4,235.00

itdd trolley, cost per mile 4,120.00

• bonding, cost per mile 684 50

. including electrical equipment
<;<iCh 12,214 no

Acuity of making repairs, but he did

not explain why or how. What is needed,

he said, is a reactance that will increase

with large current increase, so that under

normal conditions the reactance would

not greatly impair voltage regulation but

under short-circuit conditions its counter

f. would increase and keep down the

ormal flow of current.

C. W. Stone expressed the opinion that

a generator built to have twice the in-

'crnal reactance of the present designs

lid not have as great a factor of

•-ty. Moreover, its reactance would

not serve to limit the effect upon the

system of a short-circuit within its own

ntuTc windings.

1 OF Electric Railway Operation
rJ. F. Wood presented a paper relat-
ing to the electrical operation of the
Vest Jersey & Seashore Railroad (a
double-track line from Camden. N. J.,
»o Atlantic City), which was remarkable

TABLE 3. COST OF MAINTENANCE OF TRANSMISSION SYSTE.MS FOR
THE YEAR 1910

Moiuh

Ilicn Tension ;Overhe.\d Trolley Third Rail

Rl-XNiNCJ Tr.\<k
Bonding

i Per
Total 1 .Mile

Total

Per
Mile

Total

Per
Mile

Total

Per
Mile

January

February

March . ."

April

May

•5142 96
109.74
198 62
403.44
256.14
123.21
167.90
357.20
508.51
604 . 93
171.58
100.34

S2.04
5.85
2.84
5.76
3.66
1.76
2.40

.5.10
7.26
8.64
2.45
1.43

S690 84
266.38
381.28
446.57
291.51
864.62
393.62
317 49
389.73
245.75
363 35
244 02

S35.32
13.62
19.49
46.71
30.49
90.44
41.17
33.21
40 77
25.70
38.01

S492.96
.580.80
495.55
745.16

1,126.40
957.42
818.29

1,631.72

838.87

647.27

11,062.98

1,466.71

82.74
4.41
3 76
5 26
7.95
6.75
5 77

11.51
5.92
4.57
7 . 50

10 35

826 67
562 82

39.26

30.24
190.05
312.08
494.79

32.99
202.05

98.66
189.83
125.03

81.51
3.75
0.26
0.20
1.27
2.08
3.30
0.22
1.35
0.66
1.26
0.S3

July

.August

September

October

November

December

Year

83,444.57

S4 10 St, SO.-, If, S3B 70

810,861- 13

86,46

82,445.72

St. 36

and highly commendable for the com- of road is 64.6 miles and there is a

pleteness and frankness of information
presented. The power station, located at
Westville, N. J., is equipped with four
Curtis turbo-.cenerators of 2000 kilowatts
each, generating three-phase alternating
currents at 6600 volts, which are stepped

branch line of 10 miles from a point
about iialf way on the main line. The
third-rail method of communication be-
tween the car motors and the line is used.
The cost of changing the line from a
steam line, about half of which was

COST OF OPERATION AND MAINTENANCE OF SLBSTATION.-
mn THE YEAR 1910

Total for Eight .^i'b.'^tations

January. .
February.
.March . .
April ...
May

June

July

August

Setitember

October

November

December

Year

Operation

81,573.82
1,601.78
1,618.16
1 728 98
1,760 46
1 794.44
2,006.97
1.751.03
1,776.14
1,744.23
1,750.62
1.745 68

820,852.31

Maintenance

275.64
370.91
432.55
317.62
194.13
903.45
145.99
142.23
130 02

2,679
1,890.
1 .892
1.875

$24,459 61

Cost per
Kilowatt-
Hour

001136
.001157
001035
001251
001267
.001310
.001047
.000811
.001285
001069
0009S6
000829

Substation

Output
Kilowatt-
Hour. 675
Volts
Direct-
("iirrcnt

1,655,800
1.460,200
1,678,400
1,554,900
1,635,900
1 ,655,600
2.175.700
2.349,000
2,035.200
1,712 100
1,860.100
2.199.100

21,072.300

up to 33,000 volts by air-blast trans-
formers in the station. The alternating
current is stepped down and converted
to direct current of 675 volts in eight
substations provided with the usual
equipment of transformers and rotary
converters. The length of the main line

single track, to the present electrical
lines, is given in Table 1.

Table 2 shows the cost of operating the
power station in complete detail for
the year 1910, and Tables 3 and 4 show
the cost, by months, of maintaining the
transmission system and the substations.

TAltl.E 5. GE.NEUAL POWER DATA

1909

1910

M*.

_

,_

= ^§

t^

-5

III

m

= -§

aa

-a

|2|

Month

filo

^8

11

= 15

ill

Janiiarv . .

1 .9.-.!l.-'Hl

.-> 67

3 23

76 1

2.l:il.l)<HI

5 15

3 31

81 8

February

1 .756 500

5 71

3 25

76 1

1 .8fl5.3(MI

5 73

3 46

82 4

•.!arrh

1 .(tort 600

6 04

3 33

76 1

2.IAN.fMKI

5 42

3 27

81 3

April

1 .Kfl!l .-WKl

5 90

3 27

75 0

2.03I.4(MI

fi 62

3 22

80 1

Mav

1.78S.W)0

5 65

3 26

75 5

2.1t5.<HKI

ft 2ft

3 27

79 ft

l,74fl.2(KI

S 77

3 22

77 7

2. 167. .50(1

ft 68

3 14

80 3

.lulv

2.f.?n.0<K)

.5 21

3 25

78 0

2,7« 1.30(1

5 H8

3 16

82 ft

AUKII 1

.' (?I.1(M)

5 27

3 34

81 5

3. 088 ..too

ft II

3 06

80 7

.SerilemlK^r

J II Ml HKl

fi 28

3 34

80 3

2..'i90.400

ft 17

3 31

82 9

October

1 ■• 11'. fWlO

5 40

3 27

HO 1

2.229.000

ft 48

3 17

80 8

November

i>i;'i :<(X)

5 49

3 41

80 7

2.3SI..'iO(l

ft 19

3 29

81.9

Decemtier

,i.l.-.4.K(»0

5 42

3 41

81 0

2.7.59,300

ft 31

2 39

83.4

Average for vear

1. 982,600

6 55

3 30

7H 4

2.359.400

A 42

3 2.'i

81.6

62

POWER

July 11, 191 :

Table 5 gives a summary of the cost
of converting enerp.y, the specific fuel
consumption and thi efficiency of elec-
trical transmission for the years 1909
and 1910.

The author presented a great deal of
other data on operatiiig costs relating
to the purely railroaa side of the prob-
lem, which does not come within the
province of Power.

Electric-.moior Control

In a paper entitled "Automatic Motor
Control," Arthur C. Eastwood inflicted
upon a body of men assembled for the
increase and promulgation of electrical
knowledge a commonplace description
of a motor controller which his company
recently put on the market and which
had been sufficiently described in the
columns of the technical press months
ago. The device is merely an ingenious
variant of the well known multiple-
solenoid-switch type of motor starter,
and is of neither sufficient importance as
an item in the progress of electrical en
gineering nor of sufficient novelty in
principle or application to justify its hav-
ing been given a place on the program

G. R. Radley and L. L. Tatum read
a paper on "Limitations of Rheostatic
Control" in which they presented a lot
of thoroughly well known and universal-
ly recognized facts concerning the mini-
mum practical number of contact points
on motor starters and regulators, the re-
sults of distributing the starting resist-
ance in different ways between the sev-
eral sections, the starting characteristics
of meters with different kinds of load,
the properties of various commercial re-
sistance materials and the temperature
considerations in designing a rheostat.
The platitudinous nature of the paper
is well illustrated by the following ex-
tracts: "Coarse steps tend to cheapen
the rheostat," "Where the load of a
motor at any speed is approximately con-
stant, resistance control is practically,
though not always, economical." "The
limit of coarseness of stepping is the
increase in voltage the m.otor will stand
without obiectionable surge of current."
"The limiting features in the resistance
material appear in getting the current
into the resistor ana getting the heat out
of it." "How to get the heat out of the
resistor is determined by a study of the
laws of the Pow of heat." "The limita-
tions of contacts or switching parts are
carrying capacity and commutating capa-
city" [ability to close and open the cir-
cuit]. "Laminated copper leaf brushes
giving a well distributed pressure over
the contact area are commercially best
for large currents."

T. E. Barnum presented a paper on the
"Control of High-speed Electric Ele-
vators" which almost comes within the
criticisms of both the Eastvt-ood and the
Tatum papers. Mi. Barnum described
commercial apparatus which is already

thoroughly well kr.own to every engi-
neer in the country who has the slightest
professional interest in elevator work
and presented a few expressions of opin-
ion as to the comparative merits and
appropriate fields of the worm-gear and
the traction types. His paper was re-
lieved of entire barrenness, however, by
the inclusion of some interesting curves
showing the performance during acceler-
ation and retardation of different ele-
vator equipments and w-ith different types
of control and some general figures as
to power consumption. He emphasized
the fact that comparison on the basis of
power consumptnn is usually unsatis-
factory, citing the following figures: A
gearless traction elevator running empty
and stopping at every floor in both di-
rections took 6.4 kilowatt-hours per car-
mile; the same elevator with maximum
load and again stopping at all floors re-
quired only 10.4 kilowatt-hours per car-
mile. Carrying two-thirds of its maxi-
mum load and stopping at all floors it
took 8.8 kilowatt-hours and with the
same load, stopping only at the top and
bottom of the well, it took only 2.4 kilo-
watt-hours per car- mile.

Overhead Wires

A valuable paper on the sag of over-
head wires was presented by W. L. R.
Robertson, in which very comprehensive
formulas and charts were offered for the
solution of sag and span problems for
all usual conditions. A kindred paper
was presented by Prof. Harold Pender
and H. F. Thompson, but this one was
even more comprehensive, including a
consideration of both the mechanical and
electrical features of transmission-line
construction and maintenance. The
mathematical and graphical character of
both papers makes it impracticable to
abstract them or even to present a rough
synopsis of their tenor.

Voltage Troubles in Small

Alternators

By H. K. Sprague

In the operation of small alternating-
current generators, poor voltage condi-
tions sometimes cause a good deal of
annoyance to the attendant in charge of
the equipment because it frequently hap-
pens that electrical machinery of limited
capacity is placed in charge of men whose
training and experience have been al-
most entirely along the lines of steam-
boiler and small-engine operation. The
causes of poor voltage are in the main
so readily determined that everyone
should know what they are. Low voltage
may be due to the speed of the gen-
erator or that of the exciter being below
the normal; to the reversal of one or
more field-magnet coils; to incorrect
switchboard instruments; to the current
in a compensating field winding being

opposed to that flo'ving in the main field-
magnet coils; to incorrect setting of the
rectifier brushes or of the exciter brushes,
or to leaving too much rheostat resist-
ance in the alternator field circuit. If the
exciter series field winding is reversed or
short-circuited, or if a part of the ex-
citer shunt field winding is reversed, low
voltage will result at the generator ter-
minals because of insufficient excitation.
It always pays to remember that the
voltage delivered at the terminals of any
generator, either direct current or alter-
nating, depends primarily upon three fac-
tors: the speed of the revolving part,
the number of armature conductors with-
in the influence of the field and the
strength of the field. All three of these
factors are present in both the alter-
nator and its exciter. They are not com-
plex in themselves and their effects there-
fore may be quickly determined and
easily controlled.

Increase of Electrical Power
in South Africa

Consul Edwin N. Gunsaulus, of Johan-
nesburg, Transvaal, reports some interest-
ing facts relative to the progress of elec-
tricity on the Witwatersrand, as shown in
the annual report of the government min-
ing engineer. There was a large increase
in the use of electrically driven machin-
ery in connection with the mines, the
horsepower of motors having risen during
the year ended June 30, 1910, from 76,-
299 to 108,354. Owing to the fact that
the electrification of the power supply
of a majority of the mines is now rapidly
going ahead, this total will be largely
increased during the present year. This
scheme contemplates not only the em-
ployment of motor-driven turbo-compres-
sors for supplying compressed air, but
motors will also be used for winding
and pumping and in a majority of cases
for the mill drive. The induction motor
has been chosen by many of the mines
for winding purposes, this being generally
the case when it was necessary to con-
vert an existing steam hoist, but it is
understood the Ward Leonard system has
been adopted in most instances where a
completely new winding plant was re-
quired.

The rated capacity of the stations now
in process of construction by the Victoria
Falls Power Company and the Rand
.Mines Power Supply Company, Limited,
is: Brakpan. 12,000 kilowatts; Simmer
Pan, 18,000 kilowatts; Driehoek, 3000;
Rosherville, 50.000 kilowatts; Vereenig-
ing, 40,000 kilowatts. The first three
are practically completed, and the Rosher-
ville station is under construction. In
addition to the supply available from the
above mentioned companies, several
groups of mines have their own electric-
power stations either in process of con-
struction or enlargement.

July 11, 1911

POWER

-^- ~^-x

-n

1 gomel

■lllll.53» t

Dgay

Fuel Oil Heating and Alarm
System

I have noticed very little data pub-
lished relative to oil-burning plants in
general and do not understand why. I
suppose that if someone would start a
discussion, the oil-burning engineer would
have something to say.

As engineers find it necessary to use
live steam to heat the fuel oil, the fol-
lowing may be of interest to them:

At the plant where I am employed two
oil tanks are arranged as shown in the
accompanying illustration, each of 100
barrels capacity, set on a platform about

m

tank. There should always be enough
water in the tank to cover the tee open-
ings, as the live steam being discharged
directly into the oil will cut it and some
of the moisture will remain suspended.
I once found it necessary to boil a 2.S0-

HEATiNG Tanks and Alarm Systpm

7 feef above the ground level. By hav-
ing two tanks it is possible to heat and
bum the oil in one while drawing it
from the other. The livc-steam conncc-
llons are arranged as shown. The pipes
A A should be placed in the center of the
lank, each having a tee on the lower end
which should rest on the bottom of the

barrel tank of oil for 48 hours after it
had been cut by steam in this manner.

The whistle alarm is quite necessary
in the pinnt mentioned, as if is the fire-
men's duly tf> fill these tanks, and it
seemed that they were always busy at
Fomelhing else when the tank got full.
The whistle can be heard in the most

remote parts of the plant. It is installed
and operated as follows:

B is the steam line used to heat the
cil. The whistle C is placed in the 1-
inch tee drilled and tapped for it. D
is the cord to which is attached a jug,
tightly corked, which acts as a float.
The cord runs over a small pulley at
the top of the tank and down the side
through a hole in the platform. The
weight £ is attached to the end of the
cord and is heavy enough to work the
whistle-valve lever when the oil reaches
a predetermined hight.

When the whistle starts sounding, the
tone is low at first, increasing in volume
as the valve continues to open, and blows
vntil the hook connecting the cord to
the valve lever is removed. It is neces-
sary to go to the top of the tanks to
ttop the flow of oil, but this is no incon-
venience.

When filling the other tank the whistle
lever is turned half way around and is
operated in the same manner as with the
other tank.

B. S. Hartley.

Tipton, Cal.

Handling the Draft

Most firemen hold the idea that the
longer the damper remains closed the
more coal they are saving. This is
wrong, because it is necessary to burn
coal rapidly to get the test results. This
cannot be done with the damper closed
and it is no more reasonable to close
the damper too early than it is to close
the exhaust valve of an engine too early.

A pound of coal will give up between
12,000 and 11,000 B.t.u. while proper
combustion is taking place, whether it be
one minute or one hour. 1 would not
close a damper earlier than 10 pounds
above the working pressure and would
cut down the boiler capacity so that
bright fires would be required to handle
the load. It may take a little of the en-
gineer's time to teach the fireman to
handle the fires so as to maintain a
steady steam pressure, but it can be
done with a little perseverance, and then
it will be unnecessary to use the sur-
plus radiating surface of an extra boiler.

Ton much attention cannot be given to
the boiler settings. Walls with an air
space are inccting with little approval
nowadays. Instead of leaving an air
space I have packed asbestos on each
side of the boiler extending from the
front to the rear and as low as the

64

POWER

July 11, 1911

grates. Tliis space was about 4 inches
wide, with several bricks put in as
stretchers to stay the wall. As a conse-
quence, the radiation of heat from the
furnace has been greatly reduced.

W. D. DUiMAR.

Attleboro, Mass.

Sectional Damper Regulator

Some time ago, while acting as master
mechanic of a New England textile mill,
I was considerably annoyed by the fre-
quent binding of a 10-foot damper that
controlled the furnace draft from the
stack end of the economizer flue. No
sooner was one cause effaced than an-
other would arise. The damper really
needed renewing as it showed consider-
able wear, the effect of 15 years' ex-
posure to the gases, but because its re-

one day he exhibited sketches of an ar-
rangement, showing how the damper
regulator could be made to control each
individual section independent of the
other. His idea was to close one section
when the steam pressure was within 7
pounds of maximum, a second when
within 5 pounds of maximum, and the
third section to shut when the steam
pressure was within 3 pounds of the
blowing-off pressure. He was positive
that such an arrangement would result
in the saving of considerable fuel and
from the ardent manner in which he
delivered his arguments I became so
convinced that good results would be
obtained by their incorporation that I at
once prepared to adopt his ideas. The
controlling valves, hydraulic chambers,
etc., were all made in our small machine
shop, and in their construction and as-

scheme, contending that the saving in
fuel was really due to the changed meth-
od of firing and that with a strong draft,
a higher furnace temperature would be
obtained. One day I cut out one boiler,
disconnected the damper mechanism and
restored the damper to its former condi-
tion. The result was an object lesson
to my assistant.

I believe his scheme possesses many
points of interest to engineers and may
aid some to better the control of the air
supply to heating coils, drying rooms, or
anything else other than the control of
furnace draft. For this reason a short
description of the apparatus may be of
interest. Referring to Fig. 2, AAA
indicate the three hydraulic chambers,
one to manipulate each of the damper
sections. B B B are the three controlling
valves which admit water to the cham-

Fic. 1. Damper

placement would necessitate the removal
of a part of the side wall and cause
sundry delays I had postponed the dis-
agreeable task from week to week.

Finally. I evolved the plan of erecting
a new damper in three sections, each
measuring 3 feet 6 inches by 6 feet in
dimensions. These sections could be
readily passed singly into the flue through
the end doors and pulled along under
the economizer tubes to places where
they were assembled.

Fig. I illustrates the damper as erected
and the method of its control. The full
lines show the closed position and the
dotted lines represent its open position,
also that of the operating levers. A
young engineer to whom the operation of
the power plant was entrusted was very
enthusiastic about the change made and

Fig. 2. Arrangement of Hydraulic Cylinder Fig. 3. Controlling Valv;

sembling I was careful to follow the
young engineer's details.

I had no doubt that the result would
prove a decided benefit as an object les-
son if in no other way. One of the argu-
ments for the scheme was that as the
rather heavy draft would be somewhat
reduced at the working pressure the fire-
men would be compelled to fire lighter
and more often. My mental comment
was that the engineer would be the one
to compel them to do this, for I foresaw
that he was about to enter on a course of
instructions to the firemen that would
compel his damper scheme to show a
material saving of fuel. I was right for
the logbook figures showed a substantial
saving of 6 per cent.

Later, however, after the firemen had
become proficient, I opened fire on the

bers and control the discharge of the
waste water. The device operates as
follows: When a predetermined steam
pressure is reached the weight D, lever
G, and the valve stem of B are raised
slightly, the amount depending on the
leeway allowed between the lever and
the toe of the screw H. When the steam
pressure is sufficient to overcome the
gravity of the additional weight K, the
lever G again rises until it comes in con-
tact with screw L, lifting the valve stem
of the second valve.

Fig. 3 illustrates one of the controlling
valves in detail and shows how each
.section of the damper can be operated
independently of the other.

Cadwalader Hughes.

Saxonville. Mass.

July 11. 1911

POWER

65

Recording Instruments for
Small Plants

In these times of competition between
the isolated plant and the central sta-
tion, the neglect of accounting methods
in the former is regrettable. The majority
of small manufacturing concerns employ
all sorts of red-tape formalities to re-
duce the waste of material, but in the
power plant practically nothing is known
about the power obtained from the coal
consumed.

All necessary apparatus can be pur-
chased for a few hundred dollars, and
practically entail no extra work on the
part of the employees. In about 90 per
cent, of the small plants such instru-
ments would pay for themselves in a
very short time.

The instruments required are usually
an automatic water weigher or a reliable
meter, a recording-pressure gage and a
recording feed-water thermometer. Some
method of weighing coal is, of course,
desirable, but in the small plant, where
coal is delivered about as used, this can
be approximated very closely when
the time of the run is for two or three
weeks.

In many steam plants the engineer
takes electrical readings every 15 min-
utes. In the average plant this alone
is not worth the trouble, as steam is
generally used for industrial purposes
and is very apt to vary, but the electric
load on the switchboard will average up
evenly.

A water weigher should be read once
each day and this reading, with the
charts from the recording instruments,
should be delivered to the man in charge
of the plant. These records, taken for
a month, and that of the total coal con-
sumption, afford a practical power-plant
test. The addition of wattmeter read-
ings also points out how much of the load
is for power and how much is for other
purposes. ,

Coal showing good economy in one
furnace may not give satisfactory re-

■;=i in another, and it is evident that a
1 ing in fuel can be made in any fur-
nace if the right kind of fuel is burned.
With proper recording instruments the
engineer may experiment with the dif-
ferent grades of coal until he has deter-
mined which is the most efficient for his
plant.

To know the chemical and heat values
of coal is important in checking up the
value of the coal as it is delivered to
'='■" if it Is up to the contract speciflca-

I'xpcrts do not agree on the best meth-
od of firing as so much depends on the
furnace. The instruments will also en-
able one to determine which particular
method of firing is best for any type of
furnace.

Steam is frequently lost because of
leaky return pipes from the heating

system. This is liable to happen when
the returns are not readily accessible
for inspection. The temperature of the
feed water will indicate the amount of
steam being returned to the heater.

Where the coal can be weighed as
used it is a close check on the fireman,
and the difference in coal fired per
pound of water evaporated by the men
will be surprising. This will also start
a rivalry between firemen which will
have a beneficial effect on the coal pile.

The central siation offers to furnish
current at a certain price. With proper
instruments in a plant the buying of
power is not guesswork. Power can be
purchased for a guaranteed price, and
if the isolated plant is not producing
power at as low a cost a reliable test
should be made to determine what per-
centage of the total cost of power should
be credited to the switchboard and what
percentage for industrial purposes. The
latter must be furnished even if current
is bought and must be taken into con-
sideration before condemning the iso-
lated plant.

John Bailey.

Milwaukee, Wis.

Main Bearing Experiences

Some time ago, while in charge of an
I8x36-inch Corliss engine, 1 was greatly
bothered by the tendency the main bear-
ing had toward heating. I experienced
but little relief after thoroughly clean-
ing what I could of it, and cooling
dopes proved their uselessness. I was

Air Pipe to Main Bearing

soon compelled to discard the oil cups
and to flood the journal with a stream of
oil flowing directly from the gravity feed
pipe. I had no time to jack up the shaft
and rebabbiti the journal, as it was im-
perative that the engine be kept in ser-
vice seven days a week.

Some relief was had by running a
pipe line from an air receiver to a hole
drilled in the side of the pillow-block, as
at A in the accompanying illustration.
The air escaped from every opening
around the shaft.

About this time there appeared in
Power discussions concerning the best
method of cutting oil grooves in larRC
journals. Some favored smooth bearings
with no channels whatever, and others
related how they got relief by cutting

the oil grooves in the shaft instead of in
the babbitt. In this vexing dilemma I
was willing to try anything which gave
promise of relief, so I cut grooves in the
fhaft, with the result that my troubles
completely disappeared. Let not the' ad-
vocates of this method rejoice unduly at
my success, however, for as 1 was cut-
ting the channels the chisel encountered
a substance difficult to chip, a piece of
cast steel imbedded in the softer material
of the shaft. Its position corresponded
with a shallow groove worn in the babbitt
of the quarter boxes; and I believe it
was the removal of this sharp alien mat-
ter that cured my trouble, and not the
cutting of oil channels.

1 was once called into u neighboring
plant to see if I could ascertain what
caused a large, main driving belt to run
considerably to one side of the flywheel.
The trouble was remedied by leveling the
engine shaft, which was easily accom-
plished, as the main inboard bearing was
equipped with a bottom wedge placed
there for that purpose. But why the en-
gineer could not attend to this puzzled
me until he explained that he not only
took up on the side liners of the main
journal, but also took up on the bottom
wedge. He believed that the sole box
wore as much as the side boxes and that
they should, therefore, be taken up the
same amount. This would be all right,
provided he frequently centered the pis-
ton and paralleled its rod with the guides;
but evidently he overlooked the fact that
there were no ready means of adjusting
the sole box of the outboard bearing.

Most all main pillow-blocks are con-
structed somewhat on the same principle;
\et, once in a while, a designer will in-
troduce some novel feature which sur-
prises the engineer. 1 once ran a high-
speed Corliss engine, with the side out-
line of the main bearing looking like the
illustration shown. The oblong pieces
of boards B B are about H inch thick,
vhich form a buffer for the wedges C C.
Why wood is used here, was never ex-
plained to me; and 1 conjecture that its
purpose was to deaden pounds, which
might arise at this point.

On one occasion 1 was sincerely thank-
ful that it was wood, and not metal; for,
one day, one hacked out of its place, an
inch or so, and an upper corner caught
in a rib of the exhaust eccentric. Im-
mediately there was trouble, which made
its presence known by the shot-like pop-
ping of the cylinder-relief valves. When
the engine was slopped it was discovered
that the sudden impact between the metal
and the wood had caused the cccenlric
to slip; and as a result, compression in
the engine cylinder became abnormal.
I believe that if the liner had been made
of anything less easy to splinter than
wood, we would have suffered at least
a broken eccentric.

WiiiiAM Powell.

Ashland, Mass.

66

POWER

July 11, 1911

Writing for the Technical
Paper

I have noticed several contributions in
the technical journals on the subject of
writing for the technical paper, and I
will try to say a few words that may
help those who are backward in giving
others the benefit of their experiences,
as well as to those who might profit by
them. No one man's experience can be
as broad as are those of a great number
of men. Our most valuable knowledge
comes from reading the experiences of
others.

There were at one time many, and
there are yet a few, engineers who are
so selfish as to keep to themselves every-
thing they know, or think they know.
The engineers who give others the bene-
fit of their experiences receive in re-
turn the experiences of others, and their
knowledge grows accordingly. The non-
committal engineer never gets very far.

Often we think we have the right idea,
or the right solution of a problem, and
we send it to our paper. The first thing
we know some fellow gets after us and
shows us that we are wrong. We are
therefore possessed of additional knowl-
edge which has cost us practically noth-
ing. It is no disgrace to be mistaken;
we are not the only one who have made
mistakes.

When we are convicted of error in
this manner the effect is wholesome; I
know because I have been the criticized
as well as the critic, and I am proud to
say that I have taken my medicine with
good grace. Our best friend is the man
who tells us in a nice way where we are
in error, and our next best friend is the
fellow who tells us anyway, even if he
may not be as considerate as we feel he
ought to be. We dislike to be convicted
of error, but this dislike operates to our
great advantage; having once been con-
victed, we will think pretty hard before
committing ourselves a second time, and
the habit of thinking is certainly a good
one to acquire.

On the other hand, we may find some
brother engineer seeking just the in-
formation we have obtained through our
experience. Here is an opportunity to
help others and help ourselves at the
same time. I say this because, in a
broad sense, anything which elevates
the individual engineer contributes just
so much to the elevation of engineers
as a class, and therefore it is our duty
to do all we can to elevate the standing

Comment,
criticism, suggestions
and debate upon various
articles. letters 3nd edit-
orials which have ap-
peared in previous
issaes

of the engineer, individually and col-
lectively.

Writing is simply a matter of effort.
If a man can talk with his brother engi-
neers, as nearly any engineer can, there
is no reason why he cannot write as well
as he talks. If he did not try, he would
not be able to talk. Many engineers
who think nothing of writing to another
engineer and telling him of some experi-
ence, and thoroughly describing everj'-
thing connected with it, would not think
of writing of this same experience for
his technical paper. Perhaps if they
realized the possible value of some of
their experiences to other engineers they
would have less hesitancy in going into
print.

William Westerfield.

Lincoln, Neb.

The Need of an Institute of
Operating Engineers

The poor working conditions of op-
erating engineers, the slight favor in
which they are held by many employers
as compared to the employer's respect
for a consulting engineer, and the very
poor wages generally paid are frequently
set forth in Power.

We need organization, but there are
inherent conditions which, because of
scattered and isolated places of employ-
ment and lack of suitable public-safety
laws, limit the scope and freedom of
action of an engineers' organization.
Most operating engineers' organizations
have the fraternal and beneficial ele-
ments, but the benefit of their educa-
tional advantages to the individual en-
gineer depends directly on his own ability
to understand and his ambition, and as
there are no grades of membership, he is
not rated according to his ability, or
elevated in proportion to his experience,
knowledge, ambition, etc. Modern in-
dustrial conditions make it necessary tc
begin a movement of genuine self-help
and uplift for the engineer as an in-
dividual.

Many years ago the engineer simply

started and stopped the engine and made
steam; he could qualify in a day. With
improvements, larger units, and in-
creased pressures and power the engi-
neer served as a handy man or a me-
chanic; he made the adjustments and
repairs, but lacked the technical knowl-
edge.

The demand today for skilled, prac-
tical and technical men is not fairly com-
pensating the engineer for his ability to
operate the close-design, high-efficiency
plant. An engineer cannot, on account
of his isolation, be cooperative and com-
panionable.

The lax laws in many cities and towns
and the employer's ignorance of effi-
ciency, economy and possible improve-
ments in operating a plant are also for-
midable reasons for these conditions.
The eight-dollar man is often as accept-
able to the employer as is the twenty-
dollar man, though the former's care-
lessness or ignorance may cost from two
to ten times the salary of a skilled en-
gineer.

While there are engineers who receive
from S20 to S40 a w-eek, many only re-
ceive S9 to S15 for seven 12-hour shifts,
including the holidays. In some instances
they are compelled to do the wiring, fir-
ing, belt repairing, piping, take care of
radiators and machinery, and assist in
the shipping room.

If the owners and the public coop-
erated they would realize that efficiency
and safety are not to be had after this
fashion; that our laws would be better,
and an employer would be suspicious of
the man who would work for low wages.

I concur with G. G. Hall in the March
28 issue of Power when he says that he
sees no reason why a chief engineer
should not be able to install a plant if
necessary; that engineers should break
away from plant routine occasionally and
view the plant from an outsider's stand-
point. When his employer knows, say,
by a certificate, that the engineer is fully
qualified, improvements will likely be
made. Through the cooperative and edu-
cational features in the plans of the In-
stitute of Operating Engineers the em-
ployer would know his engineer's
abilities.

The operating engineers should he
able to convince his employer that heat
principles and mechanical and theoret-
ical operating conditions are best under-
stood by the engineer and that they
should be intrusted to a well paid, good-
grade engineer.

July 1!, 1911

POWER

I agree with H. H. Burley, in the
April 18 issue, that the solution of these
problems does not rest so much upon an
organization resolved to stick together
as it does upon one with a view to rais-
ing the individual standard along edu-
cational lines; that the time is ripe for
all to come under one name and one
purpose and to get busy.

An engineer cannot demand higher
wages until he can convince his employer
of the danger and the lack of efficiency
in the employment of low-grade men.
Cooperation is necessary.

There are some who are afraid of
encouraging the colleges and schools be-
cause of what might be called machine-
made engineers. Nothing is farther from
the truth. A school does not claim to
make a student an engineer, but only a
better engineer than one without its as-
sistance.

The plans of the Institute of Operating
Engineers, by apprenticeship, lectures,
libraries, etc., aim to help us to be better
qualiRed for our work, and to give the
employer a better idea of what our ser-
vices are worth.

Ultimately, a qualified member will
be able to properly install and operate
in an economical and businesslike man-
ner any modem plant.

It is obvious that in a few years' time
an engineer who cannot get the very best
results will not have charge of a plant
of any importance.

We owe much to our technical maga-
zines for their advice, their uplifting
editorials and cheerful answers to prob-
lems.

The Institute of Operating Engineers
will also be of great benefit to the pub-
lic, and through public safety to better
laws.

Remember the positions with salaries
instead of the jobs at wages go to the
professions, so ours must be elevated
to an acknowledged profession.

William C. Thorne.

Vineland, N. J.

( cntral Station versus Isolated

Plant

I have been much interested in the
' entral Station versus Isolated Plant"
cussion.

The plant in which I am an engineer is
;Mcd in a small country village nearly
c miles from a railroad, and all of our
il has to ^e hauled by teams. The
il (Pennsylvania Morrlsdalc) costs
35 per ton, laid down at the plant. Be-
'-■en the boiler and engine there are
•H feet of straight pipe and 7 ells. The
f;inc is 11x15 inches in size and runs
^;0 revolutions per minute. The Initial
steam pressure is only 85 pounds, where-
as the gage pressure at the boiler is 110
' 'iinds. About 93 horsepower arc dc-
loped by the engine. During the day

run of 10 hours, somewhat more than two
tons of coal is consumed. To this must
be added a small amount which is used
by the watchman during the night.

In the majority of the articles I have
read on this subject, the engineer is
more or less to blame for the conditions
which cause the general manager to look
up central-station prices. Such is not my
case. My engine is working as well as
an engine of its type can be made to
work. I put my indicator on regularly
and keep an accurate record of what it is
doing. .As I do my own firing it goes
without saying that the quantity of coal
used is as low as possible. 1 am pro-
ducing power cheaper, by the general
manager's own admission, than my pred-
ecessors, but I am compelled to agree
with him that central-station power is
still cheaper for us under present con-
ditions, which cannot be altered without
prohibitive expense. Thus it is up to me
to take a "central-station pill," although
the manager has made it an easy dose
by adding to my file of recommendations.
Emmet Baldwin.

Sturbrldge, Mass.

Cwrrosion of Steam Boilers

I notice in the June 13 issue an arti-
cle by Walter C. Edge, on "Corrosion
of Steam Boilers." On page 911, Mr.
Edge states as follows:

"A solution of caustic snda in water
is known as soda Ive. For ordinary cases,
40 pounds of soda ash, 60 pounds of sal
soda or 35 pounds of caustic soda per
1000 gallons of water will be sufficient
to precipitate most cf the scale-forming
matter. The cost of treatment with soda
is very low. only about one grain of
soda ash being required for each grain
of sulphate."

The writer believes that the above must
be a misprint as regards the amount of
water to be used, as 40 pounds of soda
ash to 1000 gallons of water would
make the water impossible to use for
boiler purposes.

Our experience in softening water
shows that the average hard water
throughout the country only requires
from one-half to three pounds of soda
ash per thousand gallons, a-.d very sel-
dom do we find waters that require
much more than this, although we are
treating tcveral.

A water containing 21 grains of cal-
cium sulphate might, accoiding to Mr.
Edge's fipures, require approximately 3
pounds of soda ash per thousand gallons
in addition to the lime thf.t we would use
in our process.

For a w.itcr to need 40 pounds of coda
ash it must contain over 200 grains of
sulphates, which would certainly be very
exceptional.

F. S. DUKIIAM.

Chicage, III.

Furnace Questions

The questions put by Mr. Dixon in the
June 13 issue under the above heading
are on points demanding thoughtful at-
tention if high furnace efficicnc) is to be
attained. While many present-day fur-
nace installations are all right, there
are many others that are entirely unfit so
far as efficient results go, either because
of faulty design or wrong operation.

Some automatic stokers have one very
weak point in their design — they admit
air at the wrong points, at the wrong
time and in the wrong quantity. The
other day I was watching a stoker of the
inclined-front type and I noticed that at
intervals it would open up and cold air
would rush in through a slot some 2'j
inches wide, extending across the fur-
nace for its entire width. Certainly this
cannot be the best way in which to
feed air to a furnace: a sudden rush of
air, going in at intervals.

I have proved to my own satisfaction
that much economy can be effected by
providing the right amount of grate area
required by a given boiler. Some years
since we had some large boilers which
were working under a light load. The
fireman, who was considered to be a
good one, carried an open coking fire.
I noticed, however, that it was dead in
many spots. By removing two sections
of grates on each side of the furnace and
putting in blank grate bars a reduction
of about 15 per cent, in the coal con-
sumption was effected. No other change
was made.

I have tried laying a plate across the
rear of the grates just in front of the
bridgewall but I did not get as good re-
sults as when the space af the sides was
blanked off. My explanation of this is
that the sides of the furnace are the
neglected portions of the grates and are
often left bare by the fireman. Hence,
by closing them off, the inrush of an ex-
cess of cold air at those points is elimi-
nated.

Air spaces are provided in boiler set-
tings for the purpose of insulation. As
cracks often occur, a laige amount of
cold air is let into the furnace and the
economy is reduced. I have improved
boi'cr settings by tilling; the air space
with a fine sand. The sand retards the
inflow of air when cracks develop.

Rear-arch door leaks are wasteful. I
have made these doors tighter by using
in the jambs asbestos cement mixed
with Portland cement.

I agree with Mr. Dixon that the man
who has the knowlclgp can do much
if he will but get about it.

High economy calls for a plate clean
both outside and in, and good com-
bustion makes for a clean plate sn the
outside.

C. R. McGahey.

Baltimore, Md.

POWER

July 11, 1911

Vibration of Steam Reach Rod

In the reply to A. E. S., in the inquiry
department, regarding the cause of the
vibration of his steam reach rod, let me
suggest that there are several other
causes for this trouble, viz.: center
line of eccentric not in line witli the
center of the pin on the rocker ami;
bore of eccentric not parallel with the
face of the eccentric; bore of eccentric
too large for the shaft, allowing the set-
screws to put a twist in the eccentric
when they are tightened; face of eccentric
too wide for eccentric strap, making too
close a fit; hole in eccentric strap for
the reception of eccentric rod not faced
off square. Any of the above mentioned
defects will have a tendency to
cause excessive vibration. Your answer
implies that the valves are too tight
and tnat unless they are well lubricated
they will set up vibration at starting-up
time. Now this is contrary to my ex-
perience, as I have always found that
where valves were too tight, even with
plenty of lubrication, there was no vibra-
tion of the rods, but the dashpots had a
tendency to hold up and not close the
valves properly.

At a large plant in Boston, Mass., I
had an eccentric rod break off at the
brass-stub end from excessive vibration
caused by one of the above mentioned
defects. The rod was 1 !•-< inches in
diameter. Two other cases happened
within my knowledge from the above
causes.

J. F. Nagle.

Troy, N. Y.

How to Condense Steam

In response to Mr. Fldred's request in
the June 6 issue, I submit the accom-
panying sketch, which shows a simple
and cheap form of condenser that I have
had occasion to use in several plants

the cap onto the end of the 2-inch pipe.
Screw the other cap onto the opposite
end of the 2-inch pipe, letting the J/>-
inch pipe extend through the hole tapped
for the M-inch connection. A V^v-Vi-
inch bushing can then be screwed over
the ':-inch pipe and into the 2-inch pipe
as shown.

The 2-inch pipe is tapped near each
end and on opposite sides for a J<^-inch
water connection. Cold water is sup-
plied through pipe B. Steam is supplied
through pipe A and is condensed in
passing through the K'-inch pipe. Thus,
pure water is drawn off at D.

J. W. Dickson.

Memphis, Tenn.

The simple method, used by a large
electric-apparatus manufacturer, to distil
water for storage-battery work is shown
in the accompanying sketch in which B
is a large tank, open at the top, H is a
number of lead-pipe coils laid on the
bottom of the tank, C is connected to a
steam supply and D runs to the distilled-
water tank. An overflow from the tank
is provided at B, and A supplies cold
water for condensing the steam which en-
ters at C. The overflow B runs to the

Distilling Water for Storage Battery

boiler hotwell. The arrangement is sim-
ple, but does the work.

James E. Noble.
Toronto, Can.

In answer to E. G. Eldred in the
June 6 number, I would suggest that he
drill small holes in a number of steam
pipes and allow steam to blow against

be made large or small and the number
of pipes will depend on the quantity of
water desired.

John F. Davis.
Northboro, Mass.

To Mr. Eldred I offer the following on
condensing steam, which I believe will
answer the purpose:

Take a length of 54 -inch pipe and fill
it tight with clean sand. Cap up the

■/y '//,'// ■ ', — ' 'My/y//

Steam Condensed in Coil of Pipe

ends, build a good fire and start heating
at one end. When hot enough to bend
easily, commence to roll it up on a piece
of 6-inch pipe, rolling it up as fast as it
will heat. Clean the coil of sand and
take an old can or make a water-tight
box large enough to contain the coil and
fit one end of the coil through the side
near the bottom of the can. To the end
of the pipe connect a '4-inch pipe loop
and onto that place a small spigot to
drain off the water into a large bottle or
stone jug. On the upper end of the coil
connect a '4 -inch union, and file the
two faces of the union smooth. Cut a
small metal disk A that will fit in the
union the same as a gasket. Through
this disk drill three holes about 1/32
inch in diameter. Put the disk in the
union with a thin cut-out gasket on each
. side of it and connect the pipe with the
steam line. Keep the tank filled with
as cold water as can be had. The three

Construction of the Still

where the water was unfit to drink. The
outside pipe is 2 inches in diameter; the
inside one is '4 inch. One of the 2-inch
pipe caps should be tapped for a V^^-inch
pipe and the other one for a 54-inch con-
nection.

The condenser may be put together
as follows: Screw the ''-inch pipe in-
to the cap tapped for ''. inch; then screw

Steam Condensed against Side of Cold Tank

a tank made of sheet iron and filled with
cold water. At the bottom have a trough
A to catch the condensed steam and let
it run to a pail. I should build the
tank of iron, as zinc or tin might be
acted upon by the water. The tank can

spray holes in the disk will
steam and when it comes in
the walls of the coil it will
dense.

L. M. Johnson.
Glenfield, Penn.

expand the
contact with
rapidly con-

July II, 1911

POWER

39

Management of Men

In the management of men to get the
best resuhs the man in charge must
have the respect of his men. To get their
respect he must treat them as men who
are in no way inferior to him except in
the matter of work. There are many
men who are working in a lower position
than they really should be on account
of someone higher up who does not ap-
preciate their work and will not give
them their just dues. Ever>' chief should
watch and study his men and when one
shows that he is competent and deser\'-
ing of advancement, the chief should
give him what he deserves, and not sSiow
favoritism.

Fair treatment will get better results
than unjust treatment. Men dislike a
person who is always "cussing" and is
'•grouchy" with them and they will not
do as good work when he is away as
they Would if he were a man that was
respected. Of course, there are some
men who will not benefit by good treat-
ment and wtih a man of that kind one
has either to get rid of him or make him
understand that he will have to do as he
Is required.

Perhaps nothing will make a man
slight his work more when he gets the
chance than abusive language. And most
men like to have their work praised oc-
casionally.

George O. Griffith.

Fort Flagler. Wash.

Value of CO2 Recorder

It was with no little interest that I
read Edward A. Uehling's article under
the above heading in Pqiser for June 13,
answering my own in the issue of May 9.

I confess, however, to some disappoint-

.nt in not having received some help
to a clearer understanding of the rela-
tion of CO: records to boiler and furnace
-fficiency. Mr. Uehiing has neither ad-

nced £.ny argument tending to disprove
statements nor furnished experi-
mental (lata to shed light on the problem.
He appears to have read about every
second or third line of my article and
immediately dashed off a reply; other-
wise he could hardly have stated that
the writer "presents diagranimatically the
results of a number of boiler tests for
the purpose of confirming his disbelief
in the value of flue-t;as analyses in gen-
eral and automatic CO2 recorders in par-
ticular."

No such "general" disbelief was either
" pressed or implied, and I would rccom-

' nd to Mr. Uchling a more careful
perusal of the article in question, par-
ticularly ca'lipg to his attention the state-
ment that CO: recorders have a proper
place in many boiler rooms which have
previously been equipped with other in-

■ruments. especially witli devices for

'■ping coal and feed-water records.

My entire argument, perhaps rather

feebly advanced, was intended to show
that for the average boiler plant without
a technical man to interpret results, the
CO2 recorder is a rather questionable in-
vestment, to sav the least. Also, I hoped
to bring forth from someone a clear state-
ment of the value of such a recorder to
the everyday coal shoveler.

Mr. Uehiing devotes considerable space
to the well known and accepted theory
of combustion but advances no proof
that it is possible to obtain from any
furnace a truly representative sample of
gas. Therein lies no small part of the
difficulty. An automatic CO; recorder
would indeed be a valuable adjunct to
the boiler room if a fair sample could
be secured with any degree of certainty.
The use of anything for collecting gas
samples other than a single, perforated
or open-end pipe for everyday use in a
boiler flue is beset with many practical
difficulties. CO- machines, therefore,
are frequently installed by the manu-
facturers by connecting them to a single
sampling pipe in the flue. When this is
done, what guarantee has the engineer
or fireman that a fair sample is secured?
It would be easy to make the statement
that a sample thus taken is approximate-
ly correct, but it would be harder to sub-
stantiate the statement. 1 have person-
ally tried the experiment of connecting
Orsats to two different points in the flue
within a few inches of each other, draw-
ing simultaneous samples, and have se-
cured widely differing results. If Mr.
Uehiing had a car of coal to sample for
analysis 1 do not believe he would shovel
a pailful of coal from one corner of the
car and send it to the laboratory as a
fair sample.

Mr. Uehiing states that my article is
not without value fer three reasons, the
most prominent being, "because it shows
how easy it is to draw false conclusions
from insufficient data." I appreciate this
statement greatly. It would have served
admirably as a text for my first article.
It will perhaps be recollected that I there
stated that without certain other informa-
tion CO. records do not appear to have
any great value. Mr. Uehiing now comes
to my rescue by adding to the two rec-
ords (coal and water) which I considered
requisite, seven other items, "without
which," he says, "it is absurd to draw
conclusions." In this connection it is a
pleasure for me to state that all the data
he mentions were secured for each one
of the tests, notwithstanding his hasty
statement to the contrary. The additional
data were not published, the principal
reason being that I have not succeeded in
establishing .iny definite relationship be-
tween these data and the COi records.

Moreover, the average everyday fire-
man would not and could not have alt
this information at hand. If, therefore,
as Mr. Uehiing states, "it is absurd to
draw conclusions" without these data,
what does the COi recorder do for ihc
fireman ?

It must be borne in mind that in all
this argument I am considering the case
(which is most frequently met with) of
the plant where little or no technical
knowledge is available in the boiler room.

The use of a receptacle for collecting
continuous samples by water displace-
ment is also attacked by Mr. Uehiing.
While ! am inclined to believe that inac-
curacies introduced thereby are slight,
still, being short of evidence on this par-
ticular point (as Mr. Uehiing appears to
be in refuting my general argument), I
very cheerfully admit that he may be
perfectly correct in his contentions.

I might say, however, that I have on
several occasions checked a continuous
sample taken over a long period of time,
against the average results obtained from
a large number of individual samples
taken through the same sample pipe with
very satisfactory results.

Further.Tiore, several of the largest
power producers of this country, though
they are still experimenting with record-
ers, make daily use of this device, and
will continue to do so until something
more satisfactory appears.

I gladly assent to the statement made
by Mr. Uehiing that "there are certain
fundamental principles and natural Wws
with which experimental results must
harmonize and if they do not so har-
monize there is something wrong with
the results or the manner in which they
were obtained."

Now taking the results of any series
of boiler tests in which CO: and effi-
ciency results do not seem to agree (and
I have yet to see a series in which they
do agree), which figures would be most
open to question, those on which the effi-
ciency is based (such as coal and water
weights, etc.), or the CO; figures result-
ing from the analysis of something from
the flue which may or may not be a true
sample of the flue gases?

Toward »he close of his letter, Mr.
Uchling nakes the statement, "In all
cases high or low COt means high or low
efficiency." To this I most willingly sub-
scribe, but it appears to me that it is up
to him to offer some evidence that there
exist today the facilities for accurately
determining the percentage of COs
actually present in the flue gases; and
also to submit results of a series of com-
mercial boiler tests disproving my state-
ment that CO- records at the present
stage of the game are not trustworthy
as measures of boiler efficiency.

I say a series of commercial tests be-
cause by a careful system of selection
it is naturally easy to prove anything de-
sired.

It is perhaps well to add that the tests
reported in mv original article constituted
twB complete series and were, moreover,
net conducted for the purpose of proving
or disproving the value of gas analysis.
H. S. Vassar.

Bloomfield, N. J.

P O W E R

July 11. uni

Hydraulic Rani

How high will a hydraulic ram raise
water? Is it efficient and how should
it be set?

F. K. P.

A hydraulic ram will raise water,
under favorable conditions, to a hight
of 30 times its perpendicular distance
below the source of supply, and will
discharge water at a hight of 4vS feet
above itself up to about 500 feet for
every foot of effective power head. The
efficiency with this lift, however, is so
very low as to make its use almost im-
practicable, but discharging to a hight
from 20 to 4 times the head, it has an
efficiency ranging from 45 to 70 per cent.

The ram should be set level and so ar-
ranged that the overflow may not sub-
merge it, with the supply pipe as straight
as possible and of uniform diameter.

Equivalent Evaporation

During a boiler test 14.1 pounds of
water were evaporated per pound of com-
bustible from feed water at 266 degrees
into steam at 100 pounds pressure. What
was the equivalent evaporation from and
at 212 degrees?

F. H. P.

If the heat in the water entering the
boiler is subtracted from the heat in the
steam at boiler pressure and the re-
mainder divided by 970.4, the quotient
will be the factor of equivalent evapora-
tion; that is, the number by which the
actual evaporation is to be multiplied to
reduce it to the equivalent evaporation
of feed water at 212 degrees into steam
at atmospheric pressure,

1188.8 — 214.7

:i3_' = 0.98-!

970.4

is the factor of equivalent evaporation.

14.1 X 0.983 = 13.86

is the equivalent evaporation from and

at 212 degrees.

Loss of Ammonia

I am confronted with a serious loss
in the supply of anhydrous ammonia in
a compression system. The leaks are
few and unimportant; does ammonia dis-
integrate? What percentage of the full
•harge should naturally be lost per an-
num when the system is in full opera-
tion? What is the best method for de-
tecting the presence of ammonia in brine
or water? Is there any method whereby
calculations can be made as to the
amount of anhydrous ammonia required

to give a full charge in a compression
svstem?

C. A. O.
With only a few and unimportant leaks
in the compression and expansion sys-
tem, the maximum amount of ammonia
charged into the system each year should
not exceed from 10 to 25 per cent, of the
full charge. The amount lost, of course,
depends on the care the plant receives
and the quality of pipe work and fittings
used in its construction. The greatest
loss of ammonia in the compression sys-
tem generally occurs from the ammonia-
compressor piston-rod stuffing box. The
loss at this point can be kept at a mini-
mum by maintaining the rod at a uni-
form temperature; this is arrived at by
careful manipulation of the expansion
valves.

A great deal of trouble has been ex-
perienced of late years, especially in
large plants, with the loss of ammonia and
in most cases it has been found that the
ammonia lost lies dormant in the cool-
ing coils of the system, the liquid hav-
ing been made practically inactive by
mixing with water and by oil entering
the system. This difficulty has been over-
come in most cases by the use of an
efficient ammonia purifier, which must
be so installed that the accumulation of
liquid in the lowest point of the cooling
system can be drained into it.

The presence of ammonia in water and
brine can best be detected by using the
Nessler reagent. The exact amount of
ammonia absorbed by the water or brine
can only be determined by chemical
analysis, but approximate calculations
can be made when using the Nessler re-
agent, judging from the color of the re-
sulting chemical reaction.

The amount of a complete charge of
ammonia for the compression system can
be calculated approximately as follows:
Figure 0.18 pound of ammonia per foot
of 2-inch cooling coils. 0.15 pound per
foot of l'<t-inch coils and 0.1 pound per
foot of 1-inch coils. About 36 pounds
per ton of ice-making capacity is a com-
mon figure. In addition to this 250

pounds of ammonia must be allowed for
a 25-ton refrigerating machine, 350
pounds for a 50-ton. 500 pounds for a
100-ton, 650 pounds for a 200-ton, and
800 pounds for a 300-ton.

Unbalanced Pressure
In a vessel with an opening stopped by
a plug, as shown in the figure, there is
a gage pressure of 125 pounds per square
inch. What pressure will be required on
the surface C to move the plug B inward
against the pressure in the vessel?

J. S.
Supposing the joints at D D to be so
tight that there is no pressure between
the surfaces, there will be an absolute
pressure of

125+ 15 = 140 pounds
per square inch holding the plug down.
The area of a 4j4-inch circle is 14.186

-:>

-:>

>s

t

'^ , ,.

D

: .

.1

V Q

(< di'Diam. H

Sketch of Pressure Proble.m

square inches. The total pressure hold-
ing the plug down is then

140 V 14.186 = 1986 pounds.
To counteract this there is the atmos-
pheric pressure, say, 15 pounds per
square inch, plus the unknown pressure
acting upon the 9.62 square inches of
the 3 '/'-inch circle. Then

9.62 X (x + 15) = 1986
1986

^' + 15 =

9.62

X = — — — 15 =r 191.44 poutld<!

per square inch.

Surfaces may be ground so finely that
it takes a greater force to separate them
than that required to overcome the at-
mospheric pressure. This force depends
upon the perfection of the surfaces and
is obtainable only with the fine grinding
used upon the finest gages. It has not
been considered here.

July 11, 1911

POWER

71

Issued Weekly by the

Hill Publishing Company

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Entered as second class matter. De-
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.\ew York, New York, under the .\ct
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' lULLLA T/U\ liTA TIUIEST

Of this insue, 31,000 copies are printed.

yone sent free regularly^ no returns froti
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Contents

Olympic and Titanic, Ocean Giants 44

Disastrous Air Explosions 47

Features of the I-cblanc Air Pump 4S

Colors of Piping 40

Results of the Boston Anti-Smoke Law... -lO

Efficiency of Hope Drives .51

Effect of Soot on Boiler Performance .51

The Steam Turbine In Germany .52

The World's largest Crane .5-5

Intake Manifolds for Multlcyllndcr F^n-

gines 5G

Correcting Back Firing and Fuel Waste In

a I.argp Producer Gas Engine Plant... .57
Gas Producer Investigations by the I'nlted

Stales Bureau of Mines .58

Annual Convention A. L E. E. at Chicago .50
Voltage Troubbs In Small Alternators.,.. fi2
Increaw of Electrical Power In South

Africa fi2

rractlcal letters:

Fuel ftll Heating nod Alarm .System
. . . .llnbdling the Draft ... .Sectional
l>am|ier Kegiilator . . . . [Eecording In-
Ktrumculs for Small Plants. .. ..Main

n<'arlnK Experiences ri.'4-6.5

Dl»rus«|iin letters:

Writing for the Technical Paper....
The Nned of an Instltnle of (Ipcrntlni:
engineers .... Central Stnllon versus
Nolflti-d Plant ... .Corrosion of Steam
I'.'illerB .... Furnace i^iiestlons . . . .VI-
iratlon of Steam Keach Kod.... How-
to Condense Steam. .. .Management of

Men. . . . Value of CO, Krcorder on-flO

Editorials 7J.72

Cold Storage r>ufy -.-j

nmple Ice Water Supply System 74

•"Live" nnd "Dead" Frost 74

A ChanK" of Suction Pressure 7.5

To Tell Wrought Iron from Cast Iron.... 7.5
Iflcating Leaky Coll In Ammonia Con-

rteno

Inspecting Power Plant
Apparatus

Boiler and flywheel explosions are the
two main sources of serious disaster
against which engineers must be on their
guard.

It is assumed by a large number of
engineers that the boiler is the greatest
source of danger of any device in a steam
plant and, consequently, more attention
is given to it in the matter of inspection
and repairs than to flywheels.

It is a lamentable fact, however, that
hundreds of boilers are being operated
by men who through neglect allow them
to get into an unsafe condition. During
the past twenty-five or thirty years, since
boiler inspection has been carried on,
thousands of boilers have been found so
seriously defective that they have been
condemned by the inspector examining
them.

This shows that either the engineer
did not know of these dangerous defects,
or knowing, had no authority to make re-
pairs.

A boiler explosion may or may not
result in widespread disaster; it all de-
pends upon the nature of the explosion.
Statistics show that the percentage of
boiler explosions is less than is that of
flywheels, and that the average loss ratio
on flywheels is more than twice the
average loss ratio on steam boilers.

The average engineer will spend all
of a Sunday inspecting, washing and
getting a boiler ready for service, but he
will not inspect a flywheel once a month.
One reason is doubtless because a
boiler explosion makes a lot of noise,
and a flywheel goes to pieces without
very much disturbance. A column will
be given to the boiler accident in the
newspaper, but a few inches will gen-
erally serve for the flywheel accident,
even though the loss may be several
times greater than that caused by the
boiler.

Publicity has much to do with public
opinion regarding any matter and it is
mainly because of this that engineers
look upon flywheel explosions with so
little concern.

Conditions h.ive so changed over those
of a few yc.irs .igo — both steam pres-
sures and H\>vhcel-nm speed have been
increased- th.it no cnRincer can rest se-
cure reasoning that because he has never
had an accident, he never will.

Safety in a steam plant requires more
than reminiscences of past exploits. Past
successes do not make a steam plant
immune from accidents, and trusting
solely to Providence is bad practice. Not
only should boilers be thoroughly in-
spected, but the flywheel and safety de-
vices on the engine should also receive
proper attention. It is easier to prevent
an accident than it is to gather up pieces
of broken flywheels and repair the dam-
age done to both engine and buildings.

Changing Numbers

The following extract from an adver-
tisement appeared in a recent issue:

"In ordering use the new No. 10 Cata-
log. We have changed the figure num-
bers throughout, so it is very important
that you have a copy to prevent con-
fusion."

The object of the advertiser, whose an-
nouncement covers engineering special-
ties, was probably to secure a large num-
ber of replies, and he may have accom-
plished his object; but this illustrates an
unfortunate tendency on the part of many
manufacturers in revising their catalogs.
When a complete catalog is issued the
numbers assigned to machines, appli-
ances or parts which are intended to
promote accuracy :n ordering and ship-
ping should never be changed in subse-
quent editions. They ought to remain
as they were originally until the machine
or part is itself changed, when a new
number can be assigned to it. Other-
wise, the confusion, alluded to in the
above advertisement inevitably results
in many cases. By leaving these num-
bers unchanged, the manufacturer has a
complete and compact record of every
part designed for his machines, and the
user can order spares or repairs without
going into details. Otherwise, he must
specify when the machine was purchased,
give its type or pattern number if it has
one, state dimensions, etc., if he is to
feel confident that he will get what he
needs. Quite frequently time or distance
of delivery is an important element in
ordering, and an error in shipping the
wrong part may i'e ver>' costly to the
user. There is also the further advan-
tage when one number invariably desig-
nates the same part that the cost of tele-
graphing or cabling for it is reduced to
a minimum.

One of our correspondents, who called
attention to the foregoing, states that

72

POWER

July II. 1911

years ago he made the mistake of chang-
ing catalog numbers in repair-part lists
for the engines and sawmills of the Ed-
ward P. Allis Company, of Milwaukee.
A great deal of trouble resulted and it
was a long time before he heard the
last of it. He says that he never re-
peated the blunder.

Taking Stock

Once in twelve months every properly
conducted manufacturing concern strikes
a balance to determine what profits and
losses have been made during the year.

While this balance sheet usually dea's
with the manufactured goods, it is equally
important that careful atlention be paid
to the power plan;. Profits and losses
figure largely in the plant and there-
fore should be inventoried when taking
stock. Sometimes a power plant which
cost, say, twenty thousand dollars when
new, is entered as still worth that amount.
Depreciaiion is not always taken into ac-
count and the deteriorating plant from the
office standpoint is in as good condition
as when it was new.

The engine's paint may shine, its
polished surfaces and generally attrac-
tive appearance may be as good as when
first installed, but what is its condition?
Are the valves, piston rings and brasses
and bearings worn? Does it now require
more fuel to operate with the same out-
put than when the plant was new? If
it does, it is not worth the amount with
which it is credited.

When the cost of a manufactured arti-
cle becomes excessive, the reason is
quickly learned; new methods are de-
vised and the cost of manufacture is
thereby decreased.

It frequently happens that a steam
plant is not producing energy at the
lowest possible rate, and that little atten-
tion is given to the fact. Indeed, in many
instances the actual cost per horsepower
delivered by the engine is not known.
The total cost of coal, oil and supplies
in the year is usually available, but
whether the steam plant is using two
or ten pounds of coal per horsepower-
hour is not always known.

Take an inventory of :he steam plant;
perhaps the result would be surprising.
It is possible that some entries would
read:

Smokestack full cf holes. Result:
sluggish draft; low and variable steam
pressure; reduced output of factory pro-
ducts.

Cracked boiler setting. Result: exces-
sive air leakage into the furnace and
combustion chamber; incomplete com-
bustion; unburned gases go up the stack;
needless waste of money.

Piping leaking at joints, uncovered
steam pipe and stea^l blowing through
the stufRng box of valve. Result: use-
less waste of steam and increased cost
of operation.

Steam valve and cylinders of pumps
and engine worn. Result: excessi"e
steam consumption and needless expendi-
ture of money for fuei.

Such a report would start an investi-
gation if the office once realized what
such a condition meant. If an estimated
loss in dollars and cents were also pre-
sented with the causes there would be-
gin a change for the better in the steam
plant.

Such conditions are iiot at all scarce
and the plants in which they exist will
probably continue to operate as hereto-
fore. To mend matters it will be neces-
sary to go at it syitematically and get
down to the causes of power-plant losses
— and then stop them.

Less than 12 Per Cent. Steam
Engines

The tendency to break away from the
piston steam engine is evidenced by the
power plant of the Turin exposition,
which has a 600 horsepower compound
by Tosi, of Legnano, and a 500-horse-
power vertical by Swiderski, of Leipsic.
Tosi has a 4500- and Swiderski a 1200-
horsepower steam turbine, and Tosi a
600- and a 1200-horsepower oil engine;
Sulzer Brothers, of Winterthur, and Lon-
gan & V/olf, of Milan, have aii oil engine
of 1000 and 450 horsepower respectively.

Thus in a total of 10,000 horsepower
the piston steam engine has but 1100
against 3300 for the oil engine and 5700
for the steam turbine. There ate no gas
engines in the exposition.

Of course, the tendency is to exhibit
and feature the new rather than the old,
but such a power plant would have been
undreamed of a few years ago.

Teach the Bo}' a Trade

In the issue of June 27, attention was
called to the advisability of putting the
intending young engineering student in
a shop or construction work before he
enters college. Having acquired this
valuable experience he will be better
prepared to attack practical engineering
problems, and be able intelligently to
choose that branch for which he is best
fitted.

Just at this season the grammar
schools all over the United States have
turned thousands of boys away from
their doors who either from choice or
necessity will in the near future start in
to earn their own living.

It is the boy's natural inclination to
seek a position in a field where a former
schoolmate has advanced to a situation
paying perhaps eight or nine dollars a
week.

This sum looms large in the boy's
juvenile vision, notwithstanding the fact
that in the great majority of instances
this class of situations offers but little

further remuneration and still less
chances for advancement.

Taking it for granted that the boy
wants to work, by all means have him
taught a trade which has a future and in
which he can pursue his natural bent.
That many a good physician has been
lost in a mediocre lawyer is no less true
in the trades than in the professions.
Most every boy has a taste for mechan-
ical work of some kind or other, and he
should be free to fellow his inclinations
without hindrance if he is expected to
succeed.

It is a grave mistake for a man to
argue that because he has risen from
a helper in a steam plant to the posi-
tion of manager or superintendent his
son will necessarily be equally success-
ful in the same line of work.

One of the highest duties of a parent
or guardian owing to his boy is to be
certain that the young fellow is started
right, and it equally devolves upon him
to so study the boy's inclinations and
taste for a particular work that he be
encouraged to enter a field that is best
fitted to develop them.

To the boy possessed of a steady pur-
pose in life, whether he has high ability
or is but a patient plodcier, there are of-
fered great opportunities in the industrial
field today. It is not exaggeration to say
that the demand for young and skilled
mechanics — men of brains as well as
brawn, of sound judgment and resource-
ful— far exceeds the supply. Every large
company is on the watch for such young
men; they are the material of which
managers, superintendents, chief engi-
neers and other executives are made.
It is easy for the industrial army to en-
list its privates, but exceedingly diffi-
cult to recruit men who will in time be-
come "officers."

Let the boy learn a trade. It is the
stepping stone to success; it is the means
whereby the boy in time becomes "the
man who knows and does things," who
merits respect and even admiration and
develops into a good citizen and head of
a household.

Marine engineers will generally tell
yov. that too high a vacuum, does not
pay, and that they can "get more revolu-
tions out of her" with 26 or 27 inches than
with more. With the feed water heated
by the exhaust of auxiliaries there seems
to be no good reason why the efficiency
of an engine should not impro'-e as the
vacuum is increased, and Doctor Weigh-
ton says that from 25 to 28'.; inches the
gain in economy amounts to 5.! per cent,
for quadruple and 3.5 per cent, for
triple.

If some engineers actually made all
of the savings they claim to make, the
firm could, by purchasing the same
amount of coal as formerly, run the
plant and have coal to sell.

July 11, 1911

POWER

73

Refrigeration D^jpartment

Cold Storage Duty

By F. E. Matthews

It is obviously impossible to determine
with any great degree of accuracy how
much refrigeration it will take to cool a
number of differently shaped cold-storage
boxes, built by unknown methods of con-
struction, of several different insulating
materials of unknown efficiencies and
various states of preservation, into which
heat is admitted through the opening of
doors and radiated from lights and work-
men, and containing unknown quantities
of different kinds of products of vary-
ing heat-absorbing capacities, stored for
different lengths of time.

When the above list can be sufficiently
reduced, however, calculations of the
amount of cold-storage capacity required
to satisfy a certain set of conditions can
readily be made. Since lights and work-
men must be employed to a greater or
less extent, and since no insulation can
entirely prevent the inflow of heat, only
a part of the refrigeration produced by
the refrigerating plant can be employed
in cooling the stored products, the re-
mainder being dissipated.

Attempts are sometimes made to esti-
mate cold-storage duty by determining
the number of cubic feet of space to be
cooled and dividing that by the number
of cubic feet that a ton of refrigeration
is supposed to cool under average con-
ditions. While it may be interesting to
know this, such comparisons are not
only meaningless but are positively mis-
leading when the many varying condi-
tions of operation are not definitely
known. Such calculations should be
made "only on the basis of the greatest
number of known quantities and careful-
ly worked out assumptions regarding the
remaining unknown quantities.

These determinations may be simpli-
fied by the following brief method, which,
together with the accompanying tables
will, when judiciously applied, be found
accurate enough for all ordinary com-
mercial requirements.

The total amount of heat that the re-
frigerating machine must remove from
the cold-storage compartment is made
up as follows: Latent and sometimes
specific heat of the products stored, heat
evolved by lights, heat given off by work-
men, heat absorbed in the precipitation
and freezing of moisture, heat of air en-
tering through open doors, and heat en-
tering through the cold-storage insula-
tion. All of these items will be given at-
tention In this and later issues.

Cooling the Product

The amount of refrigeration required
to cool a given amount of food product
through a given range in temperature is
a practically fixed quantity for a given
product, but varies widely with different

Product

.Speciflc
Heat
.\bove
32° F.

Latent
Heat of
Freezing

Specific
Heat
Below
32° F.

Beef — lean

Beef— fat

Butter

Cream

fiff ■;;::::

Milk

0.77
0.60
0 fit
0.68
0.76
0.82
0.90
0.67
0.84
0..S0
0.51

102
72

'84
100
111
124

ii4

105

0.41
0.34
0.84
0.38
0.40
0.43
0.47

Mutton

O.visters

Poultry

Pork-fat

0.84
0.44
0 42
0 30

products. When cooling is not to be car-
ried below the freezing point the amount
of refrigeration required may be found
by multiplying the specific heat of the
product by the number of degrees through
which it is to be cooled. If the pro-
duct is also to be frozen, this amount of
refrigeration must be increased by the
amount of the latent heat of fusion, and
if cooling is to be continued below the
freezing point, the refrigeration must

It is required, for example, to cool
10,000 pounds of freshly killed poultry
through 68 degrees Fahrenheit. The
.'specific heat as given in Table 1 is 0.80
The number of B.t.u. to be removed will
be

0.80 X 10,000 X 68 = 544,000
Dividing this result by 144 (number of
B.t.u. per pound of refrigeration), the
amount of cooling duty is found to be
3777.7 pounds. If the poultry is frozen,
the additional refrigeration required will
be

10,000 X 105 = 1,050,000 B.t.u.
or (^ 144) 7292 pounds, and if addi-
tional cooling to zero degrees Fahrenheit
is required, the additional cold neces-
sary will be

10.000 X 0.42 X 32 = 134.000 B.t.u.
rr 933.3 pounds. The total refrigeration
duty required to cool the products through
68 degrees Fahrenheit, freeze it at 32
degrees Fahrenheit, and then chill it to
zero degrees Fahrenheit, would be
3777.7 + 7292 -4- 933.3 ^ 12.003 pounds
or dividing by 2000 (pounds per ton),
6 tons.

Table 2 may be found convenient in
estimating the amount of refrigeration
required to chill beef, pork and sausage
through 64 degrees Fahrenheit, or from
104 to 40 degrees Fahrenheit:

It may be notices that ten 750-pound
fat beeves, and thirty-five 250-pound hogs
require one ton of refrigeration for the
cooling of the meat alone. In estimating
the cooling capacity of a medium for
packing-house work, a ton of refrigera-
tion is allowed for from five to seven
beeves weighing from 700 to 750 pounds,
and for from fifteen to twenty-four hogs

TABLE 2 REFRIGERATION REQUIRED TO COOL MEATS

Prwiiicis

SiHciflc h-at

B.t.u lo CfKll KHKI iHiundH 1° F
B.t u. to cool l.iHio ponnrlfi 64° I-
PounrN rcrni." r.-.llon [ler 1,00(1

IMjunds (''>t 1. 1

Pounfis of m' ai roolod 64° per Ion

r'-fngr-riition

•Vveraei' «iii:hi rarcass .

(:arcAs<^ coolerl in-r Ion

0 so

SOfl
■| 1,200

3sr.

A 62.'>

0 60
600
3H.400

0 OS
080
43, .-.20

,102 22

6,61,1

32,010

226 66

8,76.1
2.10 Ih.
3fi.3

.*<au!<agc
Water)

0 6.'.
6.10
41,600

228.88

6,023

be further increased by the speciflc heat
of the prodtici below ?2 degrees Fah-
renheit multiplied by the number of
degrees through which if is cooled be-
low freezing point. The specific and
latent heat of a number of products com-
monly preserved in cold storage are
given in Table 1.

weighing 250 pounds. Still another rough
rule sometimes employed is to allow a
ton of refrigeration for from .3000 to 4000
pounds of meats cooled. These larger
figures are intended lo give ample re-
serve capacity to provide for ordinary
insulation and other losses encountered
in packing-house rrnrilcc

POWER

July 11, 1911

Simple Ice Water Supply

S\'stem

By R. C. TuRiNER

During the past ten years the manu-
facturers of refrigerating machinery have
been building small five- and ten-ton ma-
chines, many of which have been in-
stalled in office buildings and apartment
houses. In the greater number of such
installations the ice machines are mostly
used to cool water for drinking purposes.

In most ice-water systems the re-
frigerating machine is located in the
basement and furnishes refrigeration to
several hundred feet of cooling pipe lo-
cated in an open tank holding the water
to be cooled. To the tank are connected
the circulating pumps which operate con-
tinuously and discharge into the balance
tank on the roof. From the balance tank
the water returns to its original starting

Construction

This apparatus can be made larger or
smaller to serve almost any number of
rooms or people. The water-cooling tank
should be made of standard boiler steel
tested to 150 pounds water pressure.
The entrance manhole should be of
standard size as used for standard steam
boilers. The gasket for the manhole
should be made of soft rubber as it will
come in contact with cold water only.
One-inch flanges riveted on should be
used for all pipe connections. The
flanges should be placed on the tank as
follows: For the water supply, 3 inches
from the top on one end; for the dis-
charge, 6 inches from the bottom on the
opposite end. A blowoff connection
should be provided on the bottom 6
inches from the end. The supply con-
nections should be bushed by the erector
from !-inch to '..-inch pipe size. The

Section through Ice Box, Showing Tank Connections

point, the cooling tank, keeping up this
cycle of operation during the day's or
week's run.

The trouble found with many systems
of this kind, is that constant pumping
and agitating of the water muddies it
and renders it unfit for drinking pur-
poses. Another defect is the waste of
the refrigeration, owing to the use of
discharge pipes and pumps which are en-
tirely too large for the purpose. The
water traveling from the pump to the
roof, in these large pipes absorbs a
great deal of heat from their surround-
ings. Where pipes of proper size with
cork insulation are used, this loss of
refrigerating effect can be reduced to a
minimum. However, the greatest defect
lies in the excessive cost of the constant
pumping for the circulating of the water.

Following is a description and mode
of operation of a successful system in-
stalled in one of the largest office build-
ings in the South, furnishing drinking
water for a 17-story building containing
460 rooms:

discharge connections should be bushed
from 1 inch to 's inch.

A 1-inch galvanized pipe connection
for the blowoff should be extended out-
side of the ice box. All pipe used should
be redipped, galvanized. Any good
boilermaker can supply the tank and
comply with these specifications. Size
of tank over all to be 7 feet long 3 feet
diameter. The ice box in which the
tank is placed should be 4 feet deep and
lined inside with sheet copper. Walls
of this box to have an insulation at
least 8 inches in thickness.

Operation

In the mornings at 7 a.m., the dis-
charge valve should be closed; then
open the blowoff valve and let the tank
blow off for several minutes; then shut
off the fresh-water supply valve and let
all the water in the tank drain out; open
the manhole in the tank and put in 600
pounds of ice; close the manhole, shut
off the blowoff valve and open the supply
and the discharge valves. Next pack

200 pounds of ice between the outside
of the tank and the walls of the box.
During the winter months the ice on the
inside of the tank will be unnecessary,
all that would be required being 200
pounds, packed on the outside of the
tank.

The tank and ice box should be lo-
cated in the basement directly under the
drinking fountains. The ;4-'nch pipe to
supply the fountains should be covered
as follows: Rubber tape wrapped on
tight; next, thin tarred paper; third, one
thickness of common brown paper; lastly,
wrap pipe full length with I J '-inch
cloth tape. Test out the system for leaks
before applying any pipe covering. Make
the final connections to the drinking
fountains with -^s-inch brass unions. No
filters are required with this system.

The pipe supplying the fountains be-
ing so small it is only necessary to draw
off a couple of glasses of water before
a fresh supply directly from the water-
cooling tank in the basement is secured.

Where the cost of insulation for the
pipes is of no object, the discharge pipe
should be covered with cork instead of
paper.

In several installations where this sys-
tem has been installed, the pipe has been
covered as follows: First, rubber tape
is wrapped on the pipe; next, thin tarred
paper, and then a good brand of cork
.covering.

"Live" and "Dead" Frost
By William L. Keil

Among refrigerating engineers the ex-
pressions "live" and "dead" frost are
often heard and their significance is not
always understood.

"Live" frost is that which shows on
the return line coming from the dif-
ferent cold-storage rooms or ice-mak-
ing systems connected to the suction
end of the refrigerating machine. Moist-
ened fingers placed upon it adhere to its
surface. When this condition exists, the
engineer should know that the frost will
travel farther and eventually reach the
compressor, often causing a bad smell
and loss of refrigerant from the com-
pressor piston-rod stuffing boxes. In ad-
dition to this the freezing of the packing
often spoils it.

If "live" frost is found on the suction
main, a trip through the different cold-
storage rooms and to the ice-making
systems should be made immediately to
locate the coil or coils which are freez-
ing back excessively. The coils can be
found in a similar manner to which the
"live" frost is detected on the main suc-
tion line near the machine. The regu-
lating valves to these coils should be
turned off a little until this adverse condi-
tion of operation is remedied.

"Dead" frost does not cause wetted
fingers to adhere to it and is harmless
so far as the operation of the refrigerat-

July 11, 1911

Ing machines is concerned. It is also
noticeable by a slight dripping of the
i suction main. On the other hand, an
excessive dripping shows that the frost
is leaving the suction main and in this
event the regulating valves on the coils
not freezing through properly should be
I slightly opened.

I There are various causes which pro-
I duce "live" and "dead" frost in the
I suction main near the ammonia com-
I pressors. "Live" frost may be caused
I by excessive opening of regulating valves,
irregular speed of the refrigerating ma-
chine, decrease in the amount of cooling
water showered over the condensers,
causing a higher head pressure and re-
ducing the capacity of the machine.

To obtain maximum capacity per revo-
lution of the refrigerating machine,
"dead" frost is desirable up to the suc-
tion-stop valve of the compressors.

It is good practice to have marks on
the handwheels of the regulating valves
by means of which their opening can
be determined. When a regulating valve
j becomes clogged by scale or grit this
1 can be noticed by the frost disappearing
from the discharge end of the valve, and
in this case the valve should be opened
I wide to permit the scale or grit to be
I blown through into the coils from where
it will eventually pass into the scale
! separator, from which it can be removed
as required. When the valve is thor-
oughly blown through, it should be
placed back in the original position of
best performance.

A Change of Suction Pressure

I By J. M. Wauchope

I The electric light and power company
I having taken over the local ice- and
cold-storage plant to add to its 24-hour
t load, if was decided that some changes
were necessary when motors were in-
j stalled to take the place of steam en-
I gines. The engines were disconnected
and the compressors and brine-circulat-
I ing pump were driven by belt from a
1 line shaft. The plant contained two ver-
tical, dry gas compressors, one of 15
tons and the other of 6 tons refrigerating
capacity. They operated with independent
I suction, the larger on the ice tank and
1 the smaller on the cold-storage rooms.
Much trouble was had because of the
I poor insulation of the rooms, in keeping
I the temperature sufficiently low. The
engineer had carried the suction pres-
sure at ]^ pounds, and on being asked
I why he did not lower it to keep the frost
' off the machine and get lower tempera-
tures in the rooms, he replied that as he
I could not regulate the machine and had
»o much additional trouble with the rods
I the pressure was allowed to stand at 1.5.
I The machine was operating with frost
all over it and it was pounding badly.

POWER

The rod packing was frozen solid, of
course.

The pounding was stopped first by fit-
ting the discharge valves with heavy sheet-
iron shims as they were badly worn.

In the rooms the coils were located on
the side walls and consisted of six i;4-
inch pipes, there being one coil on each
side wall extending the length of the
room. The coils were fed liquid at the
top and the suction connection was made
at the bottom, as indicated in Fig. I.

The coils were then connected in series,
so that the liquid passed from one to
the other and out at the top of the sec-

Liquid

(

1

)

)

(

(

)

)

(

(

)

Fig. 1. Original Arrangement of Coils

ond coil, as indicated in Fig. 2. The
speed of the machine was then lowered
by placing smaller pulleys on the line
shaft.

As the temperature of ammonia ex-
panding at a pressure of 15 pounds is
zero it was thought that if the machine
could be operated with a suction pres-
sure of three or four pounds, the tem-
perature then being — 20 degrees, the ad-
ditional difference in the temperatures of
the pipes and air would result in suffi-
cient transfer of heat to effectually cool
the rooms.

On starting the machine after these
changes had been made, better results
were immediately obtained. The gas ex-

Liquid

Sc

c'

.. 1

J ■

C

(■

)

)

c

^ —

)

)

(

(

'

Fig. 2. Coils Connected in Series

panding up through the second coil was
dry on reaching the compressor. Good
regulation was secured, the rod packing
remained elastic and the rooms were
easily held at the desired temperature.

To Tell Wrought Iron From
Cast Iron

Cast iron h.is a much higher percent-
age of carbon than wrought iron; hence
any method of setting the surplus car-
bon free will serve to distinguish the
cast iron. To do this, dilute a little nitric
acid with three times as much water;
apply a drop of the diluted acid to the
iron and wash it off after a few min-
utes. If the spf>t is white, the piece was
wrought iron; if black from the liberated
carbon, it was c.tsi Iron.

75

Locatinir Leak.}' Coil in

Ammonia Condenser

By Ja.mes G. Sheridan

The circulating water from the ab-
sorber going to the waste tank showed
evidence of an ammonia leak in the sys-
tem, so it was thought advisable to test
the coils in one of the condensers that
was next in line for repairs. The illustra-
tion shows this particular condenser. The
ammonia vapor enters the shell of the
condenser and surrounds the condensing
coils. The cooling and condensing water
enter the junction box C by the pipe 6
and flows through the helical condensing
coils to the lower junction box and
thence to a waste tank not shown in the
drawing. The nut on the back of plug

AiMiMONiA Condenser

cock G was loosened enough so that
the plug could be driven out sufficiently
to allow some water to be drawn info
a glass and, after testing, it was found
that the leak was in the coil indicated by
H. To eliminate the joints these cocks
n-cre made up with right- and left-hand
nipples smeared with glycerin and
litharge to insure a fight joint and which
made them difficult to remove. However,
pftcr the plant was shut down, cock H
and the corresponding cock / at the top
of the condenser were removed by means
of a hacksaw and pipe caps were placed
as indicated at M. N . O and P. The de-
fective coil was thus cut out of service
and the plant was operated until the
condenser was permanently repaired.

P O VC' E R

July 11. 1911

Rohb-Brady Scotcli Boiler

The Robb-Brady Scotch boiler is a
Eiodification of the standard Scotch type.
Instead, however, of having the water and
stea'Ti space contained in one shell, it
is divided into two separate chambers.
The greater part of the upper chamber
forms the steam space. Above the fur-
naces the lower shell contains tubes
and with the additional heating surface
the shell can be made smaller in diam-
eter than the standard Scotch type. The
steam drum is attached to the main shell
by connecting necks at the front and
rear. About a foot above the bottom of
the top drum the water line is carried,
thus giving a steam space of ample
volume.

The combustion chamber is cylindrical

fV/}at file in-
ventor and fhe manu -
facturer are doing to save
time and money in the en-
gine room and power
house. Engine room
news

front neck is intercepted and the cir-
culation of the water is carried to a
point below the furnaces by a circulating
passage extending around the shell and
having its outlet near the bottom. This is
shown in Fig. 2. Therefore, the water
must flow down the front neck through
this passage and empty below the fur-
naces to replace the hot water and steam.

quent evenness in expansion, and elimi-
nating the troubles due to the water re-
maining cold at the bottom of the
boiler.

Manholes are provided which allow
thorough inspection and cleaning. One
is usually placed in the rear drum head,
and in all two-furnace boilers, one above
and one below the furnace in the front
head. Handholes are also provided in-

Fic. I. Si:cTioNAL View of the Robb-Brady Scotch Boiler

and short-screwed stays only are used.
As the shell above the furnace is filled
with tubes, longitudinal stays are not
required.

The sectional view, Fig. 1, shows that
the hot water and steam in the shell find
an outlet to the drum only through the
rear neck, as the opening through the

which always take the shortest path
to the top. This results in a very rapid
circulation and increases the economy of
the boiler, as all heating surfaces are
kept clean and in condition for free trans-
mission of heat. This complete circula-
tion also insures an even temperature
throughout the boiler with the conse-

FiG. 2. Section through Circulating
Passage under the Front Neck

suitable locations, Jsarticular attention
being given to provide means for clean-
ing the .rear tube sheet.

As the boiler is internally fired, no
brick setting is necessary. The hot gases
nre completely surrounded by water-heat-
ing surface from the time they leave
the grates until they are discharged into
the smoke fine. This excludes radiation
losses from the furnace, and those due
to infiltration of air through the setting.
The boiler is self-contained and the
cost of installation is reduced to a min-
imum.

The boiler is built for marine and sta-
tionary use in units of from 50 to 300
horsepower, and for any working pres-
sure up to 225 pounds per square inch.

This boiler is built by the Robh Engi-
neering Company. South Framingham,
Mass.

July II. 1911

POWER

The "S-C" Gage Cock.

A new design of gage cock is shown
in the accompanying illustration. The
cocl; is shown in an open and closed posi-
tion. The body of the cock is made with
a stuffing nut in which packing is placed
to keep the valve stem tight.

This valve stem is constructed with a
hollow center and has a passage to the
outside through the hole A. On the outer
end of the valve stem there is fitted an
operating member which has the open-
ing B to the atmosphere.

from which it passes through the nozzle
F to the superheater, which is made of
return bends and '4 -inch tubes, as shown
at G. A feed-water heater or economizer
is placed at H and consists of ordinary
pipe and return bends.

The operation of this steam generator
is as follows: Water is forced through
the coils H and is heated before it passes
through the pipe /. As the water passes
through the nozzle C it is broken up into
a fine spray and immediately flashes into
Steam. The steam thus formed passes

Open Position

The operation is simple. When the
lever C is pulled down the arm on the
inner end forces in the valve stem, so
that the opening at A is in communication
with the space D, which allows water
to be blown out through the nipple B.
When the lever C is released the valve
stem is forced to a closed position and
the passage A comes on the outside of
the stuffing nut. as shown by the sketch
illustrating the closed position.
■ This gage cock is manufactured by the
"SC" Regulator Company. Fostoria. O.

Steam Generator and Super-
heater
In the accompanying illustration is
shown a new design of steam generator
and superheater. The generator proper
consists of a flat 2-inch thick steel body
with upturned edges. This steel body A
Is fitted with a flat steel cap B. with ribs
on the upper side to strengthen it. and is
secured by studs and nuts. At the front

F

Closed Position

to the superheater which is placed di-
rectly in the path of the hot gases coming
from the furnace K.

If an increased quantity of steam
should be desired the feed pump can be
speeded up and the draft in the furnace
increased. The writer recently saw steam
generated from zero to 95 pounds steam
pressure per square inch in 60 seconds.

The superheater is fitted with a safety
valve to relieve it of any excess steam
pressure. Steam when first generated
passes to the bottom and rear connection
of the superheater so that the hottest
gases strike the pipes containing the
hottest steam first. The superheater and

B

|XJ^XXXXVKV?^XNX\^^2

/^z;^X777y/y?//x^/r^ Yj-a

G-

^J.

From
Purr

Sectional View of Steam Generator

is a hole in which fits a special design furnace arc inclosed in a brick setting.

of nozzle, as at C. In the rear side of This device i*; beinR handled by Charles

the body is a slot-like opening D, through Mullon ,ind Ignacy Wichrawski. 186

which the steam enters the chamber E, Union avenue. Brooklyn. N. Y.

New Reflectorscope

This instrument is not only used for
locating trouble around an engine, but is
also available for finding troubles which
cannot be observed by direct vision or
reached with the hand.

The device consists of a piece of '<;-
inch seamless brass tubing, 12' j inches
long, and supports a mirror holder which
acts on a hinge joint at the extreme end
of the tube.

The mirror is actuated 180 degrees by
a 's-inch rod which runs from the lower
end of the tube, working on a hinged
joint, as shown in the illustration.

A 2-candlepower tungsten lamp is sup-
plied with this instrument and also a

VVIfh Hond Battery With Holder

Front and Side View of Reflector-
scope

battery case. For special work, where
the batteries are separate, a holder 4
feet long and 10 feet of wire connected
to the interior of the holder are supplied.
Any lamp up to 8 volts can be used with
this device.

The device can be taken apart and as-
sembled in about one minute and will
fit any miniature pocket-flashlight battery
case.

It is readily seen that this device
makes the inspection of the interior of
an engine cylinder an easy matter, as
there is no smoke or soot to prevent it.
It is also convenient for use when ex-
amining the interior of a boiler.

The refleclorscope is manufactured by
the Rcflectorscopc Manufacturing Com-
pany, White Plains avenue and Two Hun-
dred and Forty-first street. New York
City.

POWER

July 11, 1911

Lentz Poppet Vulvc Engine

A very simply constructed four-valve
engine is illustrated and described here-
with.

pressure cylinder by a distance piece.
The feet of the high-pressure cylinder
are free to slide with changes of tem-
perature on the frame.

The stuffing box is bored and ground

Fig. 1. Side View of the Lentz Engine

In Fig. 1 is shown a side view of a
simple engine, of which the frame is of
the girder type. In compounded en-

out to 0.001 inch and in it are placed a
series of cast-iron rings, turned and
ground to fit. These rings, however,

Fig. 2. Showing Valve Gear of the Lentz Engine

ton rod to the same fraction of an inch.
Oil can be kept circulating in the stuffing
box if necessary', or water, the result of
condensation, may be used.

All the joints in the engine are metal-
to-metal, a tight fit being secured by
grinding and scraping.

In Fig. 2 is shown the valve gear. The
engine is fitted with double-seated poppet
valves. The valve seats are Vs inch
wide. The valve spindles have no stuff-
ing boxes, but they fit in long bushings
which are bored and ground to fit the
valve spindles to 0.001 inch. Grooves
to prevent leakage are turned in the

gines the low-pressure cylinder is bolted
to the engine frame and the high-pres-
sure cylinder is secured to the low-

do not touch the piston rod. Interposed
between them are five square sectional
cast-iron floating rings which fit the pis-

Fic. 3. Steam Valve Gear

spindles as shown in Fig. 3. The valves
are turned to such diameters that the
lower one will just pass through the
upper opening. No dashpots are used
to close them, but each valve is moved
by a hollowed cam acting on a roller;
when the valve is seated the cam is not
in contact with the roller, but the clear-
ance is very small. The roller is never
clear of the cam until the valve is seated;
consequently the engine runs practically
noiselessly.

A horizontal shaft rans alongside the
engine and is rotated by a bevel gear
placed between it and the crank shaft.
This shaft drives the valves, each valve
being driven by an independent eccentric
of small diameter. In order to secure
smooth running, this lay shaft is driven

Fig. 4. Sectional VIE^s' of a Tandem- compound Engine

July U, 1911

POWER

79

by a peculiar bevel friction drive. The
gears constituting this drive are in the
nature of friction cones, but, to prevent
slipping, they have ver>' shallow teeth
of a peculiar shape. The gears them-
selves are inclosed in an iron case and
run with very little noise.

with a hand-speed adjustment and the
speed of the engine can be varied while
in operation.

This engine is of German design and

Fig. 5. Parts of the Governor

Eccentrics are grouped on the shaft,
one for each valve. The eccentric rods
are coupled directly to the ends of the
cam levers. The throw of the steam ec-
centrics-can be reduced to zero by means
of a wedge, which slides in the shaft
and in the eccentrics. This wedge is
moved by the governor and regulates the
point of cutoff.

A sectional view of the engine is shown
in Fig. 4. The governor parts are shown
In Fig. 5, and the assembled governor
In Fig. 6. It is simple in its construc-
tion, consisting of the inertia weight or rim,
Fig. 7, two centrifugal weights B B and
one small, flat spring C. The outer ring
D runs loose on the lay shaft instead of
being rigidly connected to it, and directly
influences the governor spring C and the
weights B B. With the slightest change
of load and consequently of speed, this

Fig. 6. Governor Assembled

inertia force acts before the centrifugal
forces which have first to overcome the
existing friction before they can possibly
become operative. The result of this com-
bination of inertia and centrifugal action
is a greatly increased sensitiveness and
quickness in action. The travel of the
governor is directly transferred to the
two steam eccentrics without any inter-
mediate belts or links whereby the ec-
centrics are moved along a slide block,
•nd their angular advance set according
to the requirements of the load to give
proper cutoff.

When desired, the engine is provided

Fig. 7. Outline View of the Governor

is manufactured under United States
patents by the Erie City Iron Works,
Erie, Penn.

Hill Pump Ya\vq

The accompanying illustration shows
the essential features of the construc-
tion of the Hill pump valve, which is
built to meet all pumping requirements,
such as boiler feed, cold water, hydrau-
lic service, etc. The valve consists of
a bronze body into which are inserted an
outer and an inner circle of rubber se-
curely held by a 'binder ring. The rub-
ber disks are made of varying composi-

Hii I, Pi'MP Valvi;

tion accordinc to the service for which
they are to be used and arc renewable.

This valve provides that the bridge
system in the ";cat may be of the most
simple ch.iractcr. thus materially increas-
ing the valve area, and as the valve is
strongly reinforced by the metallic cover

plate, as shown in the sectional view,
it is especially adaptable for high pres-
sures and heavy-service conditions. This
Talve is made by the Hill Pump Valve
Company, IS East Kinzie street, Chi-
cago, III.

Motor Driven Pipe Thread-
ing Machine

The Curtis & Curtis Company, 85 Gar-
den street, Bridgeport, Conn., has just
placed on the market a new design of
motor direct-driven pipe-cutting and
threading machines, as shown in the ac-
companying photograph.

The die-cutting head is of the usual
Forbes pattern and is mounted on a
cabinet base. A motor, wound for any
current desired, is concealed within the
base.

The machine is entirely self-contained.
There are no outside bearings to be lined
up, and the entire machine is portable.

Motor Drivhn Pipe-threading Machine

As no countershaft or belting is used,
the operator can use a trolley over the
machine for the handling of long and
heavy lengths of pipe.

Various speeds can be obtained, or the
machine can be started or stopped by
simply throwing a lever, while the motor
is allowed to run constantly.

As the motor is situated inside of the
base, it is protected from drippings of
oil or breakage resulting from the hand-
ling of long and heavy pipes and fittings.

The machine is heavily geared with a
powerful motor, which provides ample
power for dull dies or hard pipe. The
machine does away with all thumb screws
for adjusting the dies, which arc now
clamped by one movement of a lever.

POWER

July II. 1911

Newly Desijijncd "Diamond"
Soot Blower

A new swinging-arm blower is illus-
trated herewith. Its most important fea-
ture is the protection afforded to the
inner steam pipe A. A heavy lining of
insulating packing or asbestos surrounds
this pipe, and this packing is in turn
permanently bound by the outer iron pipe,
thereby making it impossible for undue
heat to reach the inner tube. A double
protection also surrounds the elbow.

Another feature is the shelf S upon
which the arm rests when not in use, and
where it is out of the direct path of the
heat and gases.

The sectional lever L, link C and ful-
crum D are additional means by which

form a circle. The device is now manu-
factured by the Short Flexible Stuffing
Box Company. 422 First National Bank
building, Denver, Colo.

Convention of International
Association for the Pre-
vention of Smoke

The sixth annual convention of the
International Association for the Preven-
tion of Smoke was held at Newark, N. J.,
on June 2S, 29 and 30. The sessions
were held i:i the city hall and the con-
vention was welcomed to the city by
.Mayor Jacos Haussling. Papers were
presented upon "The Relation of the
Gas ProduciT to the Smoke Problem."

devices, special furnaces and hand fir-
ing, and one upon railroad smoke. The
visitors were entertained with a theater
party, a trip to Coney Island and auto-
mobile rides for the ladies.

The election resulted in the choice
of Daniel Maloney, smoke inspector of
the city of Newark, N. J., as president;
J. T. Brown, of Indianapolis, Ind., vice-
president, and R. C. Harris, of Toronto,
Can., as secretary-treasurer.

The next convention will be held at
Indianapolis during the last week in
September of 1P12.

Colonel Meier's Testimonial

The testimonial presented to Col. E. D.
Meier at the Pittsburg meeting of the
American Society of Mechanical Engi-
neers is reproduced in the accompany-
ing illustration. The presentation was
made in commemoration of his seventieth

Nl;\\ DRflGN OF DiA.MOND SOOT BlOWER

birthday and was given attention in our
report of the spring meeting in the
June 13 number.

the arm can be readily operated in close
quarters, where otherwise it would be im-
possible.

This blower is made by the "Diamond"
Power Specialty Company, 250 Fort
street. W.. Detroit. Mich.

Short Flexible Stuffing Bo.v

In the description of the Short flexible
stuffing box in the June 6 number, the
article should have stated that the master
bars have a flat face against the packing
and are set at right angles to one an-
other. The bars to which the springs are
attached have two flat sides that are at
right angles and the sides that come in
contact with the packing are cut so as to

by Prof. R. H. Fernald, of the Case
School of Applied Science at Cleveland,
and consulting engineer for the United
States Bureau of Mines; "Enforcement
of Smoke Prevention Ordinance." by
Ernest J. Lederle, Ph. D., commissioner
of health in New York City; "Smoke
Prevention in Large Power Stations," by
James T. Whittlesey, chief engineer, and
Harvey S. Vasser, assistant chief engi-
neer of tne Public Service Corporation
of New Jersey at Newark; "Smoke
versus City Beauty," by Richard B.
Watrous, secretary of the .American Civic
Association at Washington, D. C; "The
Ohio Smoke Law." by Senator John
Krause, of Ohio, and two discussions,
one upon mechanical stokers, steam-jet

SOCIHTY NOTE

The administration of W. W. Freeman
as president of the National Electric
Light Association came to a close, June
30, with a total of no less than 9214
members. He began his term with 5736
members, which would give a gain of
3478 for the twelve months. It is be-
lieved that the coming year under Presi-
dent Gilchrist may see the figures
equaled, as tliere is a strong movement
on foot in all parts of the country toward
the formation of company sections and
the affiliation of State associations. There
are indications that the membership dur-
ing the coming year will easily reach
not less than 12,000.

July 11. 1911

POWER

NEW PUBLICATION

"The Resistancesto Flow through Loco-
motive Water Columns," by Arthur N.
Talbot and Melvin L. Enger, is the title
of Bulletin No. 48 just issued by the
engineering-experiment station of the
University of Illinois.

A locomotive water column is a device
used in filling a locomotive tender with
water; it is also know as a penstock, a
water crane, or a standpipe. The larger
locomotives have tenders holding 8000
gallons of water or more. For the faster
trains the time allowed for filling is two
or three minutes. This means that a
large quantity of water must be dis-
charged through the water column in a
short time. To provide the large dis-
charge, there must be little resistance
to flow through the pipe line and water
column, or a higfi pressure and high
supply tank must be had. Ver>' little
definite information on the' hight of tank
necessary to furnish the given quantities
of water has heretofore been available.
Bulletin No. 48 describes tests which
were made on 14 kinds of water col-
umns, comprising practically every make
now used by the railways of the United
States. Aluch information of value to
the railroads of the country is given. The
discussion on water hammer, relief
valves, friction losses in pipes and el-
bows, and methods of designing water-
service installations adds to the value of
the bulletin. Copies of this bulletin may
be obtained gratis upon application to
W. F. M. Goss, director of the engineer-
ing-experiment station. University of Il-
linois, Urbana. 111.

PERSONAL

(.iiailes E. Sweet has been appointed
general superintendent of the Northway
Motor and Manufacturing Company, De-
troit, Mich.

Walter M. McFarland represented the
Society of Naval Architects at the fiftieth
congress of the Institution of Naval
Architects, which was held in London
on July 4.

Paul P. Bird, until recently smoke in-
spector for the city of Chicago, has
! taken a position with the contract depart-
I nient of the Commonwealth Edison Com-
;P«ny, Chicago. III.

j Frank G. Bollcs is associated with the
^ Advance Sales Corporati'in, New York.
j He was formerly connected with the
! Reliance Engineering and Equipment
I Company, Milwaukee. Wis.

Walter S. Hanson, fomerly president
0' the El Reno Alfalfa Milling Company.
f-\ Peno. Okla.. has been appointed man-
»Ker of the Mollis Cotton Oil. Ice and
Light Company. Mollis. Okla.

D. J. Lewis. Jr., has retired as manager
of the Bundy department of the Ameri-
can Radiator Company, .New York, and
is now sales manager of the Lytton Man-
ufactnrmg Corporation, New York.

Parker H. Kemble, district manager
of the Edison Electric Illuminating Com-
pany, of Brooklyn, N. Y.. has been ap-
pointed sales manager of the Toronto
Electric Light Company, Toronto, Can.

Resolution of Thanks to In-
stitution of Meclianiail
Engineers

The members of the American Society
of Mechanical Engineers who enjoyed
the hospitality of the Institution of Me-
chanical Lngmeers last summer have
just sent to this body a beautifully en-
grossed resolution of thanks, a reproduc-

*f-^'^

X

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:;„■.;' T..-r..T.,rr,- ia,-f.

Cornelius T. .Myers, formerly as-
sociated with the Wisconsin Engine Com-
pany, Corliss, Wis., as assistant secre-
tary and assistant treasurer, has become
identified with the General Motors Com-
pany, fietroit, A1ich.

W. M. White, formerly hydraulic cngi-
r.L-er with the I. P. Morris Company,
Philadelphia, Penn., has assumed the
duties of manager and ciiief engineer of
the hydraulic-turbine department of Allis-
Chalmers Company. Milwaukee, Wis.

tion of which appears in the accom-
panying engravmg. The appearance of
the original Is, of course, much better
than the present illustration, but the
general Jesign and the wording will be
evident.

A Correction

In a review of Pickworth's "Logarithms
for Beginners," which recently appeared
in Po'vFR, the price is given as .SI, where-
as the correct figure is M) cents.

82

POWER

July 11, 1911

You've been reading
about the champagne
riots in France.

They are nothing more
nor less than a state of
ahnost civil war over a
trade name — the use of
the word "champagne."

The situation is of national import-
ance, because of the European habit
of using geographical names for trade-
marks.

The French government was obliged
not long ago to "delimit" the area of
"Bordeaux" champagne, because it had
overlapped the geographical bound-
aries. Growers in Aube were naming
their product champagne, claiming it
to have become generic.

The big growers in France are now
pushed off the champagne platform
with a herd of others because they did
not make their products known
individually.

In a forceful way is the power of a
trade-mark being vividly demonstrated.

Conservation and popularization of
trade-mark value is the foundation rock
of manufacturing success.

Advertising is the modern way to fix
identity and affirm quality.

All of us are not only buyers but we
make something to sell and will be in-
terested to know the limitations of the
trade-mark law in the United States.

Chapman in his book
on the subject states:

A trade-mark must
not be identical with a
registered or known
trade-mark.

Must not be obviously descriptive of
the character or quality of the product.

A mere proper name.

A mere geographical name.

Mere name of building or business
location.

Name or picture of a living person
without consent.

Mere designation of material, such as
tin, paper, white leather, etc.

Designation of form, size, color or
designation of package.

Merely the color of an article or its
label.

It must not be composed of tne flag,
coat of arms or other insignia of the
United States, any state or municipal-
ity, or resemble their insignia.

A trade-mark must not be obscene or
otherwise immoral.

It must not be a niisrepresentation of
origin, make, quality, contents or in-
gredients of the article with which it is
associated, noi- he exploited by advertis-,
ing- which contains misrcpj'cscntation.

All of these limitations are an encour-'
agement to good advertising and a pro-
tection to buvers.

I

Vol. 34

NEW YORK, JUIA' 18, 191 •

No. 3

(C

c

ox," said Mac, '
jumped 50 feet !

I once knew a man what

" Mac," responded Con, " I had a brother
out in Africa who, after bein' chased ten miles by
cannibals, came to a river a mile wide. He never
stopped; he jumped over it. How's that for a jump?"

"That's a pretty fair jump,
look at the start he had!"

said Mac, "but

To get a good start makes most of the difference.
Endowed with ordinary intelligence, ■well-formed
habits of thoroughness and neatness, and an honest
desire to be something, a young man has a foundation
on which he can erect a solid, lasting structure. No
obstacle that besets the path to success is too great
to be overcome if he is quick to grasp the opportunity
and press forward.

Sure it's hard, this getting started! It means
plowing down into the dirt and drudgery that so
often discourage the beginner unless he can detect
the faint ray of light and hope that rims the cloud.
But it also means to the observing superior that the
young man armed with the broom or cotton waste
is on the alert for the dust and the grease spots; that
this young helper does not feel above his position and
is the raw material that in time will be molded into
the skilled mechanic— in a word, he is making a good
start.

These
gofxl old United
States have
hundreds of men
at the head fif
the large in-
du.stries whose
early circum-
stances denied
them the advan-
tages of what is

w^'

\/%^

i'jki. ^ '

-—

called the higher education. But they were keen to
reason that many of the men at the top once started
in very humble fashion, and that it was only by patient
industry, perseverance and a hustling desire to ad-
vance themselves that they climbed the high rung of
the ladder.

In his youth the young man finds it far easier
to get ahead than do the older ones, who are often
handicapped by family obligations and who cannot
afford to make a fresh start. Then, too, the young
man's mind will more readily grasp new ideas and
assimilate them ; his perception is more acute and his
mind is more retentive.

Often the yoimg fellow grows fainthearted because
he entertains the mistaken notion that the old man
does not want the youth to rise from his present posi-
tion and will discourage any attempt on his part to
advance himself.

The skill and good will of the subordinates are
largely necessary to the successful operation of any
plant, and every far-seeing and clear-headed chief
knows that his proper administration is dependent to
a great extent on the cooperation of the men under him.

Start right, for there is a big demand in the
itulustrial fR-ld at tlic ])rcsent lime for skilled mechan-
ics who, with a
little executive
training, pro-
gressive ideas
and energetic
methods, may
occupy i)ositifms
of trust and re-
sponsibility.

Today is the
time, now is the
hour; go to it!

POWER

July 18, 1911

An Interesting Isolated Power Plant

Several weeks ago an article was pub-
lished describing the record system kept
by Asa P. Hyde, chief engineer of the
Security Mutual Life Insurance building,
Binghamton, N. Y., of which Fredrick
W. Jenkins is president. Central-station
representatives have repeatedly attempted
tc obtain a foothold in Mr. Hyde's plant
without success. There is nothing out of
the ordinary in the equipment of this
power plant, which is located in the
subbasement of a ten-story office build-
ing; views of the engine room are shown
in Fig. I.

The power plant in this building can
be duplicated for 815,000 and a descrip-
tion of it will undoubtedly be of in-
terest and value to isolated-plant engi-
neers. Allowing 10 per cent, of the cost
price for interest and depreciation, the
fixed charges are less than 0.045 cent
and the total cost is I'm cents per kilo-
watt-hour. Were the engineers credited
with work done about the building the
cost per kilowatt-hour would be slightly
decreased. No. I buckwheat coal is
burned, costing S3 per ton. delivered to
the plant.

One reason why this plant is being
operated so satisfactorily is because the
company is satisfied to leave the entire
care, management and purchasing of sup-
plies and equipment to the chief engi-
neer. All supplies are charged up to
the departments to which they are de-
livered.

Another reason for economical opera-
tion is the care taken of the apparatus in

By Warren O. Rogers

This plant is being ope-
rated so economically that
the inducements offered by
the central station have not
made any impression upon
the management. The
plant contains ordinary
machinery and can be du-
plicated for $15,000. Many
homemade devices have been
deiised which assist in ob-
tai)iiitg high economy.

Every avenue for loss has been closed,
as much as is possible. The boilers and
the steam and hot-water pipes are pro-
tected by a covering of extra-heavy thick-
ness, many of the pipes, etc., having
had additional coverings since the origi-
nal was put on. Even the pipe flanges
and unions are protected.

All of the steam-pump cylinders are
covered and in the case of the hot-water
pumps both water and steam ends are
covered. These covers are made in two
lections and are removable where pos-
sible.

is an oil eliminator. All returns and
drips are run to an open heater which
maintains a temperature of from 210 to
212 degrees, generally the latter.

The return system is so efficient that
only enough makeup water is required to
keep the water from becoming too pure.

Economical operation is also due to
the manner in which the fuel is handled.
A daily record is kept of the day and
night coal consumption, the amount of
ashes obtained, water evaporated, which
is measured by a meter, and the total
output of the plant in electrical energy.
If the coal is not up to the standard it
is rejected.

These methods of operation enable the
plant to be run at the low cost of Sl.CK^
per kilowatt-hour, which figure was the
average for one month, all operating ex-
penses being charged up to the gen-
erators.

The mechanical equipment consists of
two 175-horsepower return-tubular boil-
ers, hand fired and operated under natural
draft that is controlled by a damper
regulator. The combustion is cairicd
back over the top in a return flue.
The boilers are set in a room
that is separated from the engine room
by a brick wall. Large windows in the
portion opposite the firing floor permit
the night engineer, who does his own fir-
ing, to have a view of the engine room
while engaged in the boiler room and vice
versa. The steam pressure carried is 100
pounds per square inch.

In the engine room there are three

Fic. 1. Two Views of the Engine Room of the Security Mutual Life Insurance Building

the plant. Although it is seven years old.
the machinery is as good now as when
first installed, and there has been no
shutdown or trouble during this time, al-
though the plant is run 24 hours a day.
This showing is due to good management
and the men all pulling together.

All of the steam-pump cylinders are
used over again, and a homemade muffler
is used through which (he exhaust steam
from the pumps and engines passes. This
muffler contains a nest of baffle plates
which act as oil extractors.

On the pipe line outside of the muffler

high-speed engines direct coupled to di-
rect-current generators. There is one
90-horsepower Ridgway engine, one 60-
l.orsepower and one 200-horsepower
Skinner engine. The first two are di-
rect coupled to a 40- and 60-kilowatt
generator respectively. The large 16''x

July 18, 1911

POWER

85

16-inch Skinner engine is direct coupled
to a 125-kilowatt General Electric gen-
errtor. Owing to the nature ef the load,
the large engine is run the greater pan
of the time. This load carries lights and
motors, the latter being used throughout
the building; also the load of the
Carnegie library, next door. The two prin-
cipal 40-horsepower motors drive two
Goulds triple-plunger power pumps,
which are used for elevator service.

pressure on the plunger of the elevator
and another gage shows the pressure
carried on the service tank.

The floor gage, shown in detail at the
left of the gage board, consists of a
graduated face over which a movable
piece travels. A weight attached to the

an operator does not obey orders he is
warned, and if he persists in disobey-
ing orders he is discharged. The motors
r.nd belt-driven pumps are automatically
controlled, starting when the water pres-
sure has fallen a predetermined amount
and stopping at the high-pressure limit.

TbCar

Fig. 2. Oil-cooling Coil

Fig. 3. Diagram of the Elevator Gage Board

Both elevator pumps have SxlO-inch
plungers and are belt driven, each pump
taking its water from a return tank and
forcing it into a pressure tank against a
pressure of 170 pounds per square inch.

The plant is full of useful, homemade
kinks, one of which is found in the oil
tank on the Skinner engine, shown in
Fig. 2, and is Mr. Hyde's idea. This
oil tank has a '«-inch perforated inlet
pipe, capped at the end, through which
flows the oil from the bearings. There
is also a coil of 's-inch piping arranged
as shown, through which cold water is
forced at the bottom and is discharged
at the top outlet. This arrangement
cools the oil coming from the bearing at
a temperature from 90 to 75 degrees
Fahrenheit after it has passed over the
water coil.

There are two Standard plunger hydrau-
lic elevators. Considerable trouble was
had at first with the men operating these
elevators, due mostly to running past a
landing and throwing the controlling lever
over suddenly in order to lower the car
to the proper level. There is a pressure
of 30 pounds to the square inch against
the plunger when the car is stationary
at the landing and 120 to 170 pounds per
square inch when the car is going up.
This practice needlesslv consumed elec-
trical energy, and the elevator men op-
erated their cars about as they chose,
when no one was looking.

When the gage board shown in Fig. ,3
was put up in the engine room, this
rractice was stopped as the engineers
on watch could see just what the ele-
vator operators were dring.

Each elevator is connected to a tell-
tale which indicates the floor at which
the car is at rest. A counter records the
number of full trips made by the car
to which it is attached; no partial trips
•re allowed. A gage designates the

movable piece causes the indicator to
descend when the car is on a down trip.
The cord attached to this indicator is
fastened to a part of the car mechanism
where the reduction of movement allows
the telltale on the gage to move the
length of the gaee board while the car is

One pump starts .Irst and the second
act!: as a booster.

Fig. 4 illustrates the pump installation
at the end of the engine room. The
largest pump is a tandem duplex steam-
elevator pump, hut is held in reserve as
the electrically driven power pumps are

Fig. 4. General View of the Elevator Pumps

making one full upward or downward
trip.

This gage shows whether an operator
is holding his car at a landing longer
than is necessary, or it is run by its land-
ing and dropped again. The pressure gage
shows whether the operator is properly
running the car; if the pre'^'ure jumps
the operator is "plugging" the car. If

used for general ser\'icc, and in this
plant can be operated more cheaply than
the steam pump. This fact was deter-
mined by practical tests. The compound
pump was tested for two days and the
electrically driven duplex pump for two
days, the number of elevator trips being
practically the same. The electrically
operated pump showed a saving of 4,S81

POWER

July 18, 1911

pounds of coal in the two days, and the
number of trips during the two tests with
the compound pump were 923 and 841;
822 and 879 trips were made with the
power pumps. The daily records always
check up in favor of the electric-driven
triplex pump; aside from this the main-
terance is much less.

Under the engine-room floor there is
a sump pit in which drips from the

on watch may know when anything
might be wrong, as the pump failing to
start up, an alarm system has been de-
vised. A float in the sump is connected
to a rocker arm A, Fig. 5, which is at-
tached to the base of the pump. From
this rocker arm a rod B extends
up to a small switchboard placed

above the pump. This rod is at-
tached to a cross arm C which
is pivoted in the center. The switch
blades D and E are attached to each end
of the arm C by means of a link. The
action of the switch D is positive, but the
switch £ is opened by the operator, al-
though it is closed by the action of the
float.

When the sump pit fills with water the
float rises, and the rod B is moved in a
downward direction. This closes the
switch D, but the switch E will remain
closed, because a slot in the guide F
permits an upward movement without its
moving the switch blade E.

When the switch D is thrown by the
action of the float the circuit is closed and
the bell rings. The engineer then knows
rhat there is trouble with the pump. The
ringing of the bell is stopped by throw-
ing open the switch A, which is made
possible by the slot in the link F.

As the water in the sump lowers the
float falls and opens the switch D and
closes the switch E which, owing to the
length of the slot in the link F, does not
make contact with its terminal until the
switch D has opened. This arrangement
automatically sets the switch for the next
sump full of water and stops the bell

Fig. 5, Sump S^x■ITCH and Bell
Arrangement

pumps and engines are collected. A
small duplex pump, which takes care of
the sump water, is set directly over the
sump pit and in order that the engineer

Fig. 6. Damper Signal Light

from ringing after the engineer has had
his attention called to the sump.

A convenient arrangement for the
night engineer is a red light attached
to the arm of the damper regulator. When
the damper is shut the light drops into a
can and is not visible in the engine or
boiler room. When the damper is wide
open the light shows and the engineer
knows that the tire requires attention.
The arrangement :s shown in Fig. 6 with
'.he damper regulator in its normal posi-
tion when but a portion of the red light
shows.

The hot- and cold-water pumps are
motor driven; the water is pumped
into tanks under 90 pounds pres-
sure. When it drops to. sav. 87 pounds
the motor is automatically started by the
reduction of water in the tank which acts
on a pressure gage. This gage has a
contact point which closes the circuit
through a magnet which acts on a switch.
As soon as the pressure has reached 90
pounds the circuit is broken and the
switch is opened. A small steam pump
is held as an emergency unit.

July 18. 191 1

P O W h R

87

An auxiliary exhaust-steam hot-water
heater is shown in Fig. 7. It contains two
sets of coils, one of 3-inch brass pipe.
through which either live steam or ex-
haust steam from the heating system

were steaming with the North Atlantic
fleet, the "North Dakota" in position di-
rectly astern of the "Delaware." We are
officially informed that average results
for 10 days show tliat using coal from

Hot Writer

S

I Cold Wafer

Fig. 7. Diagra.m of Heater for Hot-water System

and pumps can pass, and a set of 4-inch
brass coils which are connected to the
Webster vacuum return system. The sup-
ply of exhaust steam is controlled by a
thermostatic valve. Cold water enters
at the bottom of the heater and when
heated by the coils is pumped to the hot-
vater system.

Although there are a good many pumps,
etc., they are so arranged as to give a
neat, orderly appearance to the engine
room, a plan view of which is shown
in Fig. 9.

A view of the switchboard is shown
in Fig. 8. It is made of seven panels
of Vermont marble, three of which are
for the generators, and two each for the
motor and lighting circuits.

Three men are on duty during the day,
and one man during the night run. The
shift hours are from 6 a.m. to 6 p.m. and
6 p.m. to 6 a.m.

Renai.ssance of the Naval
Reciprocatin}^ Enjjine

The Scientific American recently pub-
lished an editorial, which is of such an
interesting character that we are repro-
ducing it in part.

When it was recently announced that
the Navy Department had decided to re-
turn to the reclprocaiing engine as a drive
for battleships, wa expressed astonish-
ment that this should be done at a time
when every other naval power was using
the steam turbine exclusively. That the
action of the department was based upon
fact and sound reasoning, however. Is
shown by the comparative steaming re-
sults obtained from two sister ships, the
"North Dakota." which is equipped with
turbine engines, and the "Delaware,"
driven by standard reciprocating engines.

An opportunity for comparison of coal
consumption under identical oonditinns
was recently afforded when the two ships

the same collier, employing the same
auxiliary engines, and steaming at the
same speed, of 12 knots, under identical
conditions of wind and weather, the
"North Dakota" consumed 43 per cent,
more coal than the "Delaware."

than full speed the turbine consumption
becomes relatively larger and at cruising
speed considerably so. But it has taken
such a test as this, made under sea-
going conditions, to show just how ex-
travagant is the coal consumption of the
turbine under cruising conditions.

What makes the record of the "Dela-
ware" so very significant is the fact that
she recently carried out her annual full-
speed irials, at the close of some 19,000
miles of all but continuous steaming,
and under conditions which show her
reciprocating engines to he remarkably
reliable, and capable without any pre-
'i!:''i!arv preparation of equaling and
even surpassing the results obtained dur-
ing the original acceptance trials.

After the ship had just concluded
some 19,000 miles of steaming without
undergoing any dock repair or machin-
ery overhauling whatsoever. Neverthe-
less, the "Delaware," steaming for four
consecutive hours at full power, made
an average of 21.86 knots, which is near-
ly a third of a knot more than the 21.56
knots she made on her official trials. But
she did even better than that; for on the
24-hour continuous run at full power she
averaged 21.32 knots, and this in spite of
the fact that she was burning coal only.

Fig. 9. Plan of the Power Plant

It has always been understood that the
turbine showed its best efficiency when it
was being driven at full speed, under
whicfi conditions its coal consumption
is as good if not bct;er than that of the
reciprocating engine. At anything less

had her regular watch in the fire rooms
and was cleaning fires as usual. A fur-
ther tribute to her engine-room efficiency
is found in the fact that the ship has
steamed 30,000 miles without any ad-
justment of her engines.

POWER

July 18. 1911

Equal Work in Compound Engine

A Massachuctts inspector lias a pet
question which he asks of candidates for
first-class licenses. We have not the
actual wording, but as given to us it is
something like this.

With a given initial pressure and point
of cutoff in the high-pressure cylinder
and a given back pressure in the Unv,
what should be the receiver pressure in
order that the work may be equally
divided between two cylinders having a
known ratio?

Without the introduction of the back
pressure, this might be understood as
referring to the gross amount of work
done in each cylinder, that is, to the work
done by the mean forward pressure, in
which case its solution would be easy.
To make this perfectly clear, the steam
does an amount of work proportional to
the area ABCDE in Fig. 1. but an
amount of this work proportional to the
area F G D E is required to overcome the
back pressure.

If the line A B be taken as the unit
of volume and the line A E is the unit
of pressure, the area A B H E under the
admission line will also be unity and the
area BCDH under the expansion line
will be the hyperbolic logarithm of the
total length of the diagram ED measured
in the units A B. The length £ D repre-
sents the final volume of the steam, the
length A B the initial volume and the
quotient of the final by the initial volume
is the "ratio of expansion."

In Fig. 1, E /) is four times as long as
A B. One volume of steam is expanded
to 4 volumes. The ratio of expan-
sion is 4. The hyperbolic logarithm* of
4 is 1.3863, so that the whole area
AC DE would be proportional to 1 +
1.3863 = 2.3863 for a ratio of expansion
of 4, or of 1 -f log.c r for any other ratio
r of expansion (/og.r is the usual ex-
pression for hyperbolic logarithm ).t

To find the mean or average of the
varying pressure ABC it is necessary
only to divide the area ABCDE by its
length.

The area is I h 'ogf r and the length
is r. The mean hight is then
I -t- log.c r
r
Applying this to Fig. 1 :

i_J ■- — ^ = 0.5966

4
and the mean or average pressure is
represented by the line / ./, at 0.5966 of
the hight of the diagram.

•Tallies of hyperbolic loaailthms may lip
(omul In all of the better class of engineers
rcl'iTiMU'O lioolts,

niii^ is I 111.' iiulv when the pri'ssurp varies
iin.M^rh IS Ih.' volume, twice Ihe volume
l,.,ll Ihr |,,rssurc. etc.. the product of the
iircssiii,- :iih1 volume remaining constant. In
which case llie curve is a rectilinear hyper-
holn The expansion line of an orduiary In-
dlen'tor diagram follows this law more or
less closely.

By F. R. Low

What should be the re-
ceiver pressure in order
that the ivork may be equally
'dislrituttcd between the cyl-
inders of a compound
oigiiic, initial and back
press ttrc, cylinder ratio and
point oj ciitofj in the high
pressure being knoivii?

Tliis is a pet question
with a Massachusetts exam-
iner. The article shows
how it may be solved, lite
jornnilas are simpler than
they look and require a
knowledge oj only simple
arithmetic. Incidenta lly
the article explains the pro-
cess of figuring mean effec-
tive pressures.

Fig. 2 is a combined diagrani where
the steam is expanded from B to C in
the first cylinder and to D in the second.
This latter expansion may be from C to
D in the larger cylinder if the high-pres-
sure diagram ends in a point as at C
and the back pressure is equal to the
terminal, or there may be free expansion
in the receiver as from C to M, in which
case L M would be the back pressure in
the high- and the initial pressure in the
low-pressure cylinder.

In any case, since the product of the
pressure and volume is constant the
areas of the rectangles A B P J, KCHJ
and L M N J are equal and may each be
represented by unity.

The gross work done by the high-
pressure cylinder is A B C H J and is pro-
portional to I -f log., r, if r represents
the ratio of expansion in that cylinder.

The gross work done by the low-pres-
sure cylinder \s K C D F } or l. M D F ].
The area under the admission line is the
constant product of pressure and volume
and may be represented by 1, as above
explained. The area under the expansion
line is to the area under the admission
line as the hyperbolic logarithm of the
ratio of expansion is to I. Then the
area L M D F J. for instance, would be
proportional to 1 (the area L M N J) plus
the area M D F N, which latter would be

proportional to the hyperbolic logarithm
of the ratio of expansion in the low-
pressure cylinder, which call r;.

Then the gross work in the high-pres-
sure cylinder is

1 + log.e Ti
and that in the low-pressure
1 \- log.c r.

and it is apparent that for the gross
works to be equal the ratios of expan-
sion in both cylinders must be the same.
It is possible that this is the answer
that the inspector has in mind, notwith-
standing his giving of the back pressure.
The total ratio of expansion is the
product of the ratio of expansion in the
high-pressure cylinder and the cylinder
ratio, both of which are given.

The terminal pressure in the low-pres-
sure cylinder will be the initial absolute
divided by the total ratio of expansion,
and the initial pressure in the low (that
is, the receiver pressure sought) will be
the terminal pressure multiplied by the
ratio of expansion in that cylinder, which
is the same as that given for the high-
pressure cylinder.

When, however, the net work, the dif-
ference between that done by the mean
forward pressure and that required to
overcome the back pressure (the work
represented by the indicator diagram! , is
to be made equal, the problem becomes
more complicated.

For the case where there is no drop
in the receiver, that is, where the ex-
pansion in the high-pressure cylinder is
carried to the receiver pressure and the
line K C represents the hack pressure in
the high and the initial pressure in the
low, the receiver pressure is fixed. It
will be the initial absolute pressure
divided by the ratio of expansion in the
high; but only with one cylinder ratio
will the net works be equal.

The net work in the high-pressure cyl-
inder is represented by

tlicarea.4BP7= I
plus the area RCHP= log.er\
I the area KCHJ= i
iniiuis \ or

I the area LMXJ= I

1 _^ log., r — 1 = log.c r
or is simply proportional to the hyper-
bolic logarithm of the ratio of expansion
in that cylinder.

The net work of the whole diagram is
represented by

the area /I BP J = 1
plus the area BDFP = log.c R

minus the area / ff F / = ^ «
Pi

Since we have taken A J as the initial

pressure p., the distance // = ps can be

only si-'ci part of unity as the p.- is of p.-

The highr I J of the back-pressure area

July 18, 1911

P O W H R

is represented then by the product of

Ps

and its length R, the total ratio of expan-
sion, which will be the length of the
line IE measured with A B, the initial
volume, as unity.

The net work of the whole diagram is
then proportional to

I + Icp., K—l^R

If the work is to be equally divided
this is twice what each cylinder will do;
and since the work done by the high is

log., r,

2 log.t

2 log.t

+ hg.c R — '.^ R

I =1 log.c R ■

R (I)

This allows a solution in a rather in-
<iirect way, as may be best exemplified by
trying an example.

An engine has 120 pounds absolute
initial pressure, four expansions in the
high-pressure cylinder and 2 pounds
absolute back pressure. What must be
the cylinder ratio and number of ex-
pansions in the low-pressure cylinder in
order that the net work may be equally
-distributed ?

p, = 120 r, = 4

p, = 2 log.e 4 = 1.3863

Substituting these figures in formula
1 we have

2 X 1.3683 ■

I = i^— -

A'

1.7726 = /o^.i /? — , R

The hyperbolic logarithm of the total
ratio of expansion R is enough greater
than 1.7726 to allow 1/60 of R to be
taken from it and have 1.7726 left. Take
the table of hyperbolic logarithms and
make a trial. For a ratio of 6.69 the
logarithm is 1.9006.

of 6.69 = 0.1115

1.7881

60
1.9006 — 0.1115
This is too large.

For the ratio 6.36 the logarithm is
1.8500.

;^ of 6.36 = 1.060
60

1.8500 — 0.1060 = 1.7440
This is too small.

The true value lies somewhere between
6.36 and 6.69 and narrowing down the
discrepancy by successive trial I find
1.8822. corresponding to the ratio 6.568.
to fulfil the condition.

I have prepared the accompanying
table to facilitate the calculation. The
first column in the lower portion of
Ihe table is the ratio' of the back

/.
pressure to the initial — . In this case

it Is -^ = 0.0167. The nearest value
120

to this in the first column is 0.015. Fol-

low along this line of the table hori-
zontally until the number most nearly
corresponding to the given number (that
is. twice the hyperbolic logarithm of the
ratio of expansion in the high-pressure
cylinder minus one, 2 log.e r — 1 ) . in this
case 1.7726. This is the 1.7743 in the
column for 6.5 expansions, showing that
this total ratio 6.5 is nearly right for the
given conditions.

60

of 6.568 = 0.1094

and

1.8822 — 0.1094 = 1.7738
which is as near the 1.7726 as can be
gotten without carrying the ratio to an-
other decimal place.

Proof: With 120 pounds initial and 4
expansions the terminal pressure in the
high-pressure cylinder is

120 ^ 4 = 30 pounds
The mean effective pressure in that cyl-
inder will be

This pressure acting in a cylinder hav-
ing 1.64 times the area of the high pres-
sure will develop the same power as

25.33 X 1.642 = 41.59 pounds
in the high pressure; and this is the mean
effective pressure in that cylinder as de-
termined above.

But in the inspector's example this
latio is given, and it is the receiver pres-
sure which must be varied.

The area representing the net work in
the high-pressure cylinder is ABCHJ
(1 + log.e r) minus the back-pressure

P,
High-pressure area = 1 + log^ r —

The area representing the work done in
the low-pressure cylinder is LMDFJ =
P.

area LRH J .

(&')■

log.,

minus I E F J ^ ~ R. Low-

Pi

I 4- log.r r _ _

120 X

I 4- 1.3863

— 30 = 41 .S9

If the total number of expansions is
6.568 and 4 of them occur in the high-
pressure cylinder, and there is no re-
ceiver drop, 6.58 -^ 4 = 1.642 of them
must occur in the low-pressure cylinder,
fixing the value of r.. at that quantity.
Then the mean effective pressure in the
low-pressure cylinder is

I 4- l"gr r,
Pn 1 /"«

30 X

I + 0.4959

30

1.642
0.91 1 — 2 - 25.33 pounds

and these are to be equal so that

I -f log.r r, — ^ r, = I 4- loq.c r.. — . " R
Pi P\

log.r ? 1 + 'R = log., ^2 + 7^ J-i

Substituting this expression for the
last term the formula becomes

log.r r , -f^ ^ R = log., r, + -', r, (2)

Try the case of an engine with 120
pounds absolute initial pressure (p,);
four expansions in the high-pressure cyl-
inder (r, 1; cylinder ratio (X) 3; back

90

POWER

July 18, 1911

TO FIND CYLINDER RATIO WHICH WILL PRODUCE EQUAL DISTRIBUTION OF WORK

R
Cylinder Katio ok —

loo ' r, -f

p, R

Ratio of

'">

in Low
Pressure

1.5

.75 2.00

2.25 2.50

1 !
2.75 3.00 3.25 1 3.50 3 . 75 | 4. 00 | 4 . 25 | 4 . 50 , 4 . 75 5.00 5 . 25 5 . 50

5.75

6.00

0 9510 0.9055 O.S670I0. 8341 0

S055 0.7805 0.75840. 7388 0,721310

7055ln 69121 0.6782

0.6664

0-6555

10

1 ivM I nooh (iM^ii ,oo:^:^tft'ttv>:Vo 92710

S0(i7lo S7no'o 8465 0 .S25fi 0 SOfiS 0

79110 (1 774SI0.7609

0 7483

0 7367

" ( 1 'd 1 ■■-IK"

'IS I'M) '(".',»; 0 't'llHWt 'HISlO Sss.*, f)

s7,ii, ,, s.-.ii ,1 w.v.r,

0 S2«3

') S139

I.N

11

111! 1 "

1 1 'n" - [ ■■ 1 ' 1 1 ^ " - 1 1 ( 1 •■ 1 1 ' 1 ■ 1 I

',.17- ,, •'•.!'. '< wi.-.i (1 :i(iii-.

1) SS78

' ' '

- , '

I IsP 1 1 !•;'< 1 Os'Mi I fiilH ! nil'- 1

, p ■ T' i , ,M ;-- ', '»^7 \ n \r,2'.'i

0 7I.5S6

2.0

_' (ijr, ! 1

■n i< 1 .7919

1 ..-..^I'.t i.4'.t.;i 1 . IJn 1 ] ;;-,'i; 1 ,,n~.-, 1 J., |-, 1

1.G752J1.5S19 1.7>ir..-, 1 1 in 1 ,;-m l '\W' I

JJ'i! ! ]'':;! 1 ir,,;7 1 i.:77 1 1 n_' !

,i',.;i 1 ,,7 11 1 o.-,ii. 1 (iiij'j
inr. 1 1 ii:, 1 l-'.;7 1 1071

1 . 0264
1.0919

111 •■■> 1 .S885

1.7663 1.6685 1.:)^-.! -Jl^l 1'>".I 1 n7l I

.;,.!_' 1 .;.;s., 1 ,;iiii 1 1 .■ , , \ 1 j. .1 , 1

jj- . 1 J'l, , 1 l^^.^'l 1711

1 . 1552

■> ■',]!',■ ■

1 1 7 ' ! n'^20

1 .R55lll.7529 1 .'■.'i'l,; | ,,\','ii; i ,, i-h, l I'hk) I

1 p;j 1 M7P I .;7 1 1 ! :; 1 P' i ;;i7i i

. |,;.; , n-'i'i

1 OJL'2'l k:^.-,-. ] 7 l-J 1 'n .".7 1 <,1 I'l 1 ..'M J 1

..].•■'] ! , 1 1 1 1 P ij 1 IM^s 1 ,;-ns 1

1.27j5

2.5
2.6

2.7

■ 1 |.( > 1 !■'■■■

■,s ;ii 1 ,M 1.; 1 ",u r. ! 1, !'- I 1 iJ'. 1

11,7; 1 ; . -. 1 ;,i,- 1 u.ill

1.3330

~> ,■

' 1 M 1 1 '11 " " 1 ■!• 1 1 1 1 1 V ■ ' 1 "",",", 1 1,' I-, 1 1

17:1.7 1 ,"■■,: 1 '- ' 1 4077

1.3888

•i -', ■ '

' I'l'' '(T' 1 ''"".I ] -■''■■| ->'ll 1 7'>1~

7 1 ; ; 1 t,(,s ; 1 t, ' - p, 1 .",'i;;.; I ,",». 1 7 ]

;:.■.:. 1 -• '7'. : i-u 1 J629

1.4133

i; ■" , ' 1 "r,

• •- \\i ■ 1 I'M, ■ ( 1 1 7 -- 1 ' ii; ■' . 1 ■v' 1 i 1 i ^ '■ If, 1

771; , 1 ~ " <' ■ 1 ip-- - ' 1 <; M s I Ii 1 '1 1 1

-.-,.■1 1 '■'•: ■ 1 .7.7-7 ,1..J166

1.4963

- . 1 ^ ' '. 11 ~

""";(■, > ■ ' ' 1 ■ ; 1 ■- ' 1 1 ; 1 1 1 'i .71 > i ^ >.; ; l

s ;> ! ) , s't, 1 7 1,] 1 7M'i 1 ! •>, . J I

'ill, 1 ,,1 . I 1 .'i'.l20 1.5690

1.5480

3 09862

M "1 ■ '.'(sr,

> ];]'(' " -.1 ' 1 ■ ' ' ' 1 1'l^i, ' n ' i 7 ! '1 ". '.7 1

s'i-,i> I s 1 SI, 1 sn Pi 1 , ii ,.; 1 , ;i ij 1

,,■.-,; 1 ,,7,,,, 1 6441 1.6203

1 . .=>986

3 lOSl'-.'

'('!'>■' r.si ]

■' ",( I'l ' ' ; " ' 1 ' ' . ' 1 r. 1 V ' M'^ ", ' ' 1 1 1 7 1 1

771 1 I . jr., 1 69.50 1 .6705

1.6481

' t 1 1 - ' "^ r, ■ '

. ",^ ", 1 ' ; 1 1, - ' ''■(■< ' 11"- ' (177 , '

n 1 1; , I ''(',.■;■ 1 '']•,] 1 "^ , 1 ; 1 s ;(,'! 1

Mi.;j 1 . , J7 1 74.-10 1 .7197

1.6965

f 1 "■ ( , ■ -,)■'!

' i',(,i It, ' ", 1 '■ 1 ' 1 ' . ' ■ i ', 1 ' ' ■ - . ■ 1 ',1 , - '

n 7 ;' 1 ' II ] s' p 1 '1711 1 1 '- ' , J 1 -■•■-■'i 1

-: ; • 1 ^JJ7 1 .'.i:-;,) 1 767S

1 . 7439

1 1 , ■ ■ '!'■■-

■„, ;- 1 -.111 vi_'ii 1 siol

1.7905

3.5

■ ■ ■ - ■ 1 r I '-

1 •',' ■ 1 '7 -- '(),'>; ' 1 1 ;(ii, 1 ■< V II, ]

■,-j- 1 ..1',-, 1 ssMj 1 S615

1.8361

.. , , , , ■

■ ■ -, . ■ r |v !■

■;,!■> ' 1 s (■ 1 ■ 1 '^ , ■ ( I-.I I'l ' p 1 ;^-v '

1 ',i;.i:.'j,l .'.ci.'.l.l .9070

1.8809

3.7

1 ' ■' ■ 1 ■-

' •> ' " ■ " - ■-, r, ", ' - ■ . ; ' 1 , ' 1 1' , - ' ;''".' '

' ; ; . ■ 1 , ' ' ' ' 1 . ; 1 ' , ' m > , ' ■

,)l- ; ' ,1131

1.981C

1.9518

1.9250

'.• s

1,1 ' ■ J

1 1 ■ ' 1 ■ - , ,1 1 ' "id- ' I1 1 1 ' ". ' 1 ' 1 't 1 , '

; 1 - ; ' '^ ",' 1 * ' " 1 1 ' 1 7'i 1 ' 1 .; .11 ■

,,■,7.,.. 0.^88

2.0259

1 9959

1 . 9683

-> , 1 I , ,

■ ' i , ■ ■ 1 ' 1

■ 1 1' 1 ; ' "■']'■ ' " "■! ' ' ( ,i', 1 1 ' ' "-* 1 1 ' ' ' 1 " ■ 1 ■

i' 1 1 ' 1 ' .; ;ip- ■■ ' ' , si, ' ■' ' , , ' M ' 1 '

111,, ' 1 039

2.0701

2.0393

2.0110

1 ( 1 " 11

1 1, ' i ' 'l^t, ■ ■^ 1( )- ' 7 1 f , ' 1 J 1 7 ' ' "■ ' 1

1 , ;< ' ' ,;-ii ; ■ .\ '~ '• ' "'7. ,_' ' JJ-^ 1 '

l->, ; J 1482

2.1136

2 . 0820

2 . 0530

- ■ . ■ 1 , ; ] 1

II ", 1 1 , ■ •\^\\^' • 7^7 " ' t." ' 1 ' ".-■'; '

,' 1 1 ; ' ] ;i',i 1 '.;,,,■',;'' 1 ' ' , ; ' '

J. Ill ■ 1920

2.1565

2.1240

2.0943

^ -, ] ■ -, ■ , 1

'1 1 1 ^ ■ 1 1 ". 1 ' 'I', ■ 1 ' s';"i 1 ' 7 '7 1 ' 1. . i '

, . ■ ' 1 s,", ; ' i '.;.; ■ ,;i;v 1 • :.\'> . '

. 7i ■ _':{ol

2.1987

2 . 1655

2.1351

■ ( 1 , " ; r ; 1 -. r

; ''• • ' , 1 7 -.1 ; 1 1 ■ ' ■ ' s'ti '1 ' 7^1 7 ■ t,-

1 , ". . ■ ;, : ;p> ■ I7i 1 1 ' i H J ■ ■'■''•',' '

,l->. J 2776

2.2104

2 2064

2.1753

,, 1 -,. 1 ■ 1,-, 1 ,

' i ; ; 'II'' '. 1 1 -. 1 1 , ' 'lis; ' s ; 'i 1 ' 7 , - , ■

t, ■, 1 1 * ','•]*, 7. 1 ip'' 1 ','• 1 ■ i'l, ■ '

;iil' ' .■.UI7'2 2.'.16

2 2468

2.2149

4.5

1 ) ," . . ; 7 "i 1 1

.; ,".i 111 : .:ii I 1 ; i i 1 . . ; dm 1 i j ss>7 _' 7-- '- _'

7'i I 1 _■ '>_■'! ; _■ ..'!_'■' J ,1 1 1 1 .' !..■_'

7 '1 1 1 .;,> 1 J J :\X--', 2 2.S67

2 2.541

4 'i ' 1 ' s 1

; ", ,"( 1 ", ; ;t,( , 1 ; 1 ■<>- 1 n ",' 1 1 ' 'Ml', ' ■- 1' 1 1 '

, , 's '(,.1,1 ' ),■ 1 > , ' ,',-•; ' p ■ ; . '

1 h.I J 717 . J 7,, ,77 • :j261

2 . 2928

4 7

1 r.MiM 1

; r, ;'; ", ; 1 ' "1. : ' ,ii7 ; 111; ' 'I't.'.s ' s>in'i ■

si II I'l • 7 ' T, ' i; , ; ' ,'pji 1 ' , , , ; '

I-, ,. 7 1 I J- J 1,171 ■' 365C

2.3309

4 8

t 711^"! 1

; 1 1 "i ; 'm;^(

; 7n 1 ■< ; 1 ■- -.1, , ; 1 1 1 .; 1 1,^1, ■, 1 1 1 , ', ' 'i \^\\\ ■

s [sc, _• 71; si; J »;■ i-ni 1 _> *,;,,_' , , m i j

7j-'. 7 \- • ' ■ i ; I,; 7 4034

2 . 3686

4.9

;sM ' 1 [) :■<

; ,"i , , , ■ ,'.'-■ , './ill ; ■ ' ' . ', ( i'(t,i 1 • Ms'i ' '

s'l. I'l J ^1 ! J _' , IJ 1 J ', , -^ 1 _' i,_'i 1^ J

1414

2 . 4059

5.0

1 '1 1 '7 1

I'ili ". 1 1 1 *' 1 1

; - : ; 1, , <.■ ■ 1 , . 1 ' ,"'. ; ■ .<• . 11,'' '. 1 i.i-m 1 ■

'' IJ, J ^ p'M J . ^ •' ■ 1 .!''■■ 1 'I'l Ji 1 J

I79C

2.4427

5 1

.'> 11 "• ' 1

-, 1 ; -, ^ 1 7 ■ 1

; ■. 1 ■ , , p .1 , • i - , , ' , , ! ' (-. 1 .'. 1 i-v', ; '

■IS'I ' ' '11 1 1 J ' s_'MJ ' , .,_' ' . . _'■ 1 ■

• • 1- - - .7162

2 . 4792

5.3

.". 1 1 . 1 1

tl '1 1 1 1 ' |s;

.; ' 1 , 1 ■ ; 7 - , ; .,■'),;.:-■,■; ' 1 -.7 ', 1 ; ! 1 ;

1 1 ;."i t J 'U"^ , J s , J J _■ SI 1 1 , J . 1 , ; J

■ --7 _ - _ _ ... 553C

2.5154

5 3

,'i jnin 1

ft' If. \ \ ; 1 77

1 II';; ; " s 7 7 ; , ' 1 . 1 1 , i . 1 1 , ■■ < -■ : - ' ■.

. 7 , , J ' ' , ,

.>;.J13 2.5894

2.5510

5.4

77 ' 1 1 ". ^'> 1

1 iim; 1 ; s pi 1 ; h ",i n 1 ; 1 -n 1 ; ; 1 . ■ , ' " ■ . ,

1 't; 1 .; 1 i.;(p 1 ■ 'i 1 , > 1 _• sm; 1 _■ --j ; j j

7''i''' 1 J , 1 .7, ,

6682 2 . 6255

2.5864

5 5

.'i ,17 11 1

s I 7 ( , ] 1 ', } 7

17 11.; 1 1 , 't, ' 'I'is-v ' 'ijh't J SI, ji, J

^" 1 , 7 , i77

7047 2 6612

2.6214

U.6

:, \'.i<\ 1

■ 1 ' "v ) ;, ' '-

I '117 ; 'h; 's .; 7 ",'1 ' ; ,-.' 1 . ; 1 1 ■■ ■ ; ■ ' ;

- 1 7^ 7 . -',7,

7410 2 6967

2.6561

5.7

", ", 1 1 r, ',

(i'i"'i, 1 .",'in"

1 ' 7,;s 1 ( ! '(I ", ,; s 1 ; ' ; 1 , !■ ' . ■ \ < \ \ . ,1 , < . ;

'i;i p , ; t '■ , ■ ; '1^1, ; ("',.' j ''!'',_'

.7i-,'i 2 7318

2.6905

5.8

■> 1 , ' 1 ■ ;

II,"'' t ii ".7'

1 .;;,", 7 1 M 7 , ' ' ; ^n , n ; i. - 1 ' ; , 1 .' ■ ; 1 ' .' ' ;

^1 J! 2 7666

2.7246

5.9

1 p; 1 1 7J.V

1 .;'i7 ' ! 1 .; ".' 1 .; '.ij' '.', .. . ' ■ , ; ■ ' • ; ■ p ■ ' , ;

. ; - ; ; ^ ■ l > ■ ■ -' : !-■■'' ■ ' ; , . j

-1. . 2 soil

2.7583

6.0

5,7'Jl.N.-.

„..y,7.i>

"''^"i"---^V"""""P"^'"'V'""' ■''■'.'

'J7'1?|2.L,.71. 2.--J27,2.S353

1 1 i

2.791S

%

TO FIND RECEIVER PRESSURE FOR EQUAL WORK WITH GIVEN CYLINDER RATIO

Total Ratio of Expansion

1 7.2 IS 1
1 I'lsl
1 Hils 1

0.7718
0.7 lis
0.7118
0.081S
0.65 IS
0.6218
0.5918

1)

8318

"1

7993

0

7668

0

7343

n

701S

0

6693

0

6368

0

6043

0

5718

0.82591
0 . 7009
0 . 7559
0 . 7209^
0 . 6S59|
0 . 6509
0.0159'
0 . 5S09[
0 . 5459'

.81.19 (1. 7991

899

0

5594

524

0

5194

149

°

4794

.7801
.7370
6951
6526
6101
.5676
.5251
.4826
.4401

0.712
0.667
0 622
0.577
0.532
0 . 487
0.442
0.397

.7313
. 6838
.6363
. 5888
.5413
. 4938
.4403
. 3988
.3513

,1

75

26

0

70

26

0

65

26

0

60

26

0

55

26

0

50

26

0

45

26

0

40

26

0

35

26

0

3026

(1 . 8029

0.7479

0.0929

0 6379

0.5829

0.527

0.4729

0.4179

0.3629

0.3079

0 . 2529

0.1979

449 0
0 . 0S49 0
3.6249 0
0.5649 0
0 . 5049 0
0.4449 0
0.3849 0
0.3249 0
0.2649 0
0.2049 0
0.1449 0
0.08491

0149 0

5499 0

4849

4199

3549

2899

2249

1599

0949

0299

9649 1 1

7

18

4S2

2.8004

632

2.7104

,N2

2 . 6204

932

2.5304

082

2.4404

232

2 . 3504

3S2

2 . 2604

2.1704

19

3310
0 , 4581 0 .
0.3831 0
0.3081 0
0.2331 0
0.1581 0
0 0831 1
O.OOSl'l
r 93311
1.8DSl!'i
1.7831 1

6091

.5391

4691

3991

3291

2591

1891

1191
.0491
.9791

9091

839111.7081 1
I

,1

7,ls2

111 7'. ,1

-!r!S2

.7.;2b 0

4. .32

4526

0

3682

3726

0

2832

2926

0

1982

2126

0

1132

1326

0

0282

0526

9432

9726

8582

8926

7732

8126

6882

7326

6032

6526

51S2

5726

4332

sll

7204

6304

5404

4504

3604

2704

1S04

0904

(1004

!iI04

5504
4604
3704
.2804
. 1904
. 1004
0104
.9204
8304
7404
6504
.5604
.4704
.3804
2904

2.8494
2 . 7544
2 . 6594
2 . 5644
2 . 4694
2 3744
2 2794
2 1
112 0
, 1 1 9944
,1 1 S994
1,1.8044
1 . 7094
1 6144
1 5194
1 4244
1 3294
1 2344
1 1394

1 0444
0 9494
0 . 8544
0 7594
0 . 6644
0.5694
0 4744
0.3794
0.2844
0.1894
0 0944
\ . 9994
1 . 9044
T 8094

2 7144
2 6194
\ 5244
\ 4294
1.3344
\_ 2394
1.1444

20

.8957
.7957
.6957
.5957
.4957
.3957
.2957

1957
.0957

9957
.8957
.7957
.6957
.5957
.4957
.3957

2957
.1957
.0957

9957

8957

7957
.6957
.5957
.4967
.3957
.2957
.1957

0957
.9957
.8957
.7957
.6957

5957
.4957

3957
.2957
.1957

July 18, 1911

POWER

91

pressure (p.-) 2 pounds absolute, what is
the receiver pressure?

pi given := I20 ''i ^ 4 ^ i 3863

^2 = /., H- r, = 30 r, = 2.283 = 0.8255

P, (?) i? = r, X= 12 = 2.4849

p^=: pi ^- R = 10 X given := 3

/>, given = 2

•■5863 = log.er2 + J ^j

We must now look in the table for a
hyperbolic logarithm which when it has
one-third of the number to which it cor-
responds added to it will equal 1.5863.
Try that corresponding to 2.30.
3)2.30 =0.8329
0.7667 0.7667

1.5996 this is too large
3)2.25 = 0.8109
0.75 0.75

.5609 this is too small

The value of r- is evidently between
2.25 and 2.30. By successive trials I
find that 2.283 will make

log.e 2.283 +

3

= 1.5865

The tog.r of this

which is near enough,
number is 0.8255.

The upper part of the accompanying
table will help in locating this value. In
the vertical column corresponding to the
given cylinder ratio (in this case 3)
look for the number most nearly corre-
sponding to the calculated value (in this
case 1.5863). The nearest value there
given is 1.5996 corresponding to a ratio
of expansion in the low-pressure cylinder
of 2.3 in the first column.

Since 2.283 is the number of expan-
sions which the steam gets in the low-
pressure cylinder the initial pressure in
that cylinder will be 2.283 times the ter-
minal, and the terminal is 10 pounds.
The initial pressure in the low-pressure
cylinder and the receiver pressure are,
therefore,

10 X 2.283 = 22.83 pounds

Sf^.p. in high =^ p

Proof

I 4- log.f r

-P.

120 X

2.. 1863

M.e.p. in low = />

I.82S.S _

22.83 =^ 4S 76 pounds
1 -I- tng.e r.

aa.83 X

— 2 = 16.255 pounds

As the low-pressure cylinder has 3
times the area it will do 3 times the
work with the same mean effective pres-
sure:

16.225 y 3 = 48.76

showing that its work under the given
conditions will be the same as that of
the high-pressure cylinder.

Recent Developments in Test-
ing Boiler Tubes
By F. N. Speller*

In a paper upon "Locomotive Tubes
and their Treatment," read before the
Pittsburg Railway Club and reported in
our issue of May 23, Mr. Speller de-
scribed the method followed b^ the Na-
tional Tube Company for testing each
tube before it was allowed to go out.

In the former paper Mr. Speller also
called attention to the fact that a speci-
fication of not to exceed 0.05 per cent,
phosphorus and 0.035 per cent, sulphur
is apt to make it more difficult for the
steelmaker to produce a perfectly welded
tube without a compensating advantage
to the buyer of the material. In the
present paper, which was presented at

0.150
0.140

O.IIO
■ 0.100

ao90

^ Q080
g,Q070
c 0.060
i, 0050
0.040

«/>

Enq.ne I

b

Enqine

/f

■h^l

Enqine

1 1 '■ I! Engine

.

1 i

d

—

1

-

—

J^

^^

ao3o

0.020

7Mo. lYr, 2Tr 3Yr

7Mo,8Ko. 8H0. 3Mo.

Time in Service ''°""

Diagram Showing Amount of Sulphur
Absorbed by Tube Ends from Flue
Gases in Locomotive Firebox. Low-
er Shaded Portion Shows Origi-
nal Sulphur. Open Portion,
Increase

the recent meeting of the American So-
ciety for Testing Materials, he enlarges
upon ih!s fact as follows:

Locomotive tubes whether seamless
or lap welded, must sooner or later be
safe ended; hence the welding quality
of the metal should be one of the first
considiralions in manufacture. Some
specifications now written so restrict the
chemical composition m some particulars
as to hamper the manufacturer in mak-
ing a ?ood welding steel. There is no
difficulty in making steel with a maxi-
mum of 0.03 per cent, phosphorus if
necessary, but there is reason to believe
that 0.05 phosphorus is a more reason-
able maximum limit which docs no hamt,
and, other conditions being equal, will
give a lube better adapted to service and
much more easily welded.

Another restriction which experience
teaches as operating against the best
quality of locomotive tubes is unreason-
able sulphur requirements. The highest
sulphur allowed in samples taken from
individual tubes is, in some cases, 0.035
per cent., which means that the ladle
test must not exceed 0.030 per cent. With
producer gas this signifies that the heat
must often be held and a heavier burden
of lime carried, which tends to render
the steel "dry" in welding and more
liable to be cr\'stallized or burned.

Analyses of the surface of beads taken
frc>m tubes alter being in the boiler
some time show that sulphur is absorbed
from the hot flue gases, so that if there
is any advantage in using steel of 0.030
per cent, sulphur, it would appear to
be only temporary. The results of this
Inxestigation are given in the accompany-
ing diagram. The engines from which
these tubes were taken had been operat-
ing on different roads under widely dif-
ferent conditions, but in each instance
the tubes had all given equally good ser-
vice and were being removed for safe
ending. It also appears from a compari-
son of the sulphur taken up by individual
tubes under the same conditions that
there is no consistent relation between
the original sulphur and the amount ab-
sorbed, so that it does not follow, be-
cause the tube was originally low sul-
phur, that it would therefore show com-
paratively low sulphur after being sub-
ject to the action of the hot Rue gases;
the results rather suggest that the low-
sulphur tubes are more susceptible to
sulphurizing by the hot flue gases.

A study of records in lap welding may
throw some light on the relative in-
fluence of variations in sulphur con-
tents. For example, two heats which had
been rephosphorized gave the following
welding records, each piece being tested
in the flanging machine after the first
run through the v.elding furnace and re-
jected if there was any indication of
opening at the sesm:

Chemic.vl Analyses

Percent.

Not
Welded

The average of nine heats of steel
which ran 0.03 per cent, sulphur or less
showed 20 per cent, more rejections on
account of bad welds than eight heats
where the sulphur ran over 0.04 per
cent., these heats being nearly the same
in other respects

We believe it would be to the advan-
ta(c of all concerned if a standard spcci-
flcatio.1 was agreed upon for boiler tubes,
in which there would be no objection to
a lest on the ends of each tube along the
lines described above, provided the chem-
ical requirements were not unnecessarily
restrictive.

POWER

July 18. 1911

Combined Coal and Ash Conveyer

One of the interesting features of the
power house which has recently been
completed for the Erie County Electric
Company, of Erie, Penn., is the coal- and
ash-handling system.

Coal is brought to the power house
in gondola cars and dumped into a
track hopper from which it is discharged
onto an overlapping pivoted bucket con-
veyer. Fig. 1 shows the track hopper
delivering coal to the conveyer. This

Description of a pivoted
bucket conveyer which has
recently been installed at
the poiver house of the Erie
County Electric Company.

hopper is fitted with an automatic feed-
ing device which regulates the flow of
coal to the buckets, which are car-
ried horizontally a distance of 31 feet
and then vertically in an inclosed shaft
to the top of the bins.

The coal is distributed over the stor-
age bins by means of a traveling trip-
per, operated by a winch and handwheel
placed at one end of the runway. The
storage bins and the upper run of the

Fig. 1. Track Hopper Delivering Coal to Conveyer

Fig. 2. Driving .Mechanism of Conveyer

Fig. 3. Storage Bins and Upper Run of Conveyer

Fig. 4. Hopper to Stoker by Inclined Chltes

July 18, 1911

POWER

conveyer are shown in Fig. 3. The coal
is fed to the chain-grate stokers by
means of inclined chutes, shown in
Fig. 4.

The ashes are also handled by this
conveyer line, as may be seen from the
general layout in Fig. 5. They are

drive and continuing up the curve. The
ashes are carried around the system in
the same way as the coal and are
dumped into the ash chute by means of
the traveling tripper. This ash chute
discharges through the wall of the build-
ing to cars on a siding.

placed in the basement of the boiler
house and consists of a head shaft, two
countershafts and a 10-horsepower
motor, all gear connected and supported
on a steel frame. An automatic gear
lock prevents the conveyer from run-
ning backward in the event of current

Fig. 5. Vertical Elevation Showing General Layout

■dumped from a hand car in the base-
ment onto the lower run of the conveyer.
Loading plates flush with the floor ex-
tend along this part of the conveyer for
a distance of fi2 feet, startinp from the

The conveyer is 117 feet between ver-
tical centers; it operates at a speed of
48 feet per minute and is capable of
handling .SO tons of coal per hour. The

driving mechanism, shown in Fig. 2. is

being thrown on while the motor is
loaded.

The system was designed and installed
by the Jeffrey Manufacturing Com-
pany,

Recent Work of U. S. Bureau of Mines

A large percentage of the coal used
by the departments of the Government
is now purchased on a specification basis.
During the current fiscal year the Bureau
of Mines will analyze and report on
samples representing approximately 1.-
100,000 tons, the contract price of which
Is over $.3,0''W,00(). This inspection work
will probably be considerably increased
during the next year.

The fuel-inspection work is mainly con-
tracting for fuel supply and collecting
samples for analysis, upon the results
of which depend the settlements to the
contractors, and analyzing these samples.

In drawing up the contracts and speci-
fications for fuel for public buildings, the
Isthmian canal commission, or the reve-
nue-cutter service, consideration must be
given to the fuels available in th» mar-
ket where deliveries are to be made, the
character of the equipment and any other
requirements resulting from special local
conditions. In some instances the bureau
has conducted tests in plants where a
I change in fuel seemed advisable in order

J In biticaii's iiispcclioii
work is mainly contracting
for Government fuel sup ply
and analyzing samples, hut
boiler jccd-ieater treatment
in its hearing on the eco-
nomical use of fuel and the
fundamental principles of
comhustion are also under
investigation.

«'. I>. .•<mll

^Iflllrin lit I'lttMl

Ihp riltHliiii'i! rn

"f .Morliiinl.nl KnclnciTF.

Itli 111! fiKl ii'sllnir
liiiri!. I'l'nn.. niul prcHcnldl at
••••ilnir of tlio Amorloan Horlply

to obtain data as to the economy with
which each of several coals could be
used, and savings as great as 10 per
cent, have resulted from the adoption of
recommendations based on the results
of such tests.

On some of the smaller contracts the

cost of collecting and analyzing sam-
ples may equal or even offset the gain
from buying on a specification basis; but
any such loss is more apparent than
real, as each additional contract awarded
on such a basis helps to bring about a
more careful preparation of the coal for
the market and its more economical use.
In arranging contracts and in selection of
fuels it is frequently necessary to con-
duct some special investigations and then
the engineers engaged in the sampling
assist in the work.

During the years 1909 and 1910, the
laboratories analyzed 7178 samples at a
cost per sample of SI. 54, or 1.33 cents
per ton, which is 0.48 per cent, of the
cost. For the current year the number
of samples analyzed will be approxi-
mately 878(1 and the laboratory cost will
be $1.44 per sample. Computed on a
tonnage basis, the cost will be 1.12 cents
per ton, or 0..W per cent. As the coal
purchased by the Government is used
in plants scattered all over lUc central
and eastern portions of the United States.

94

POWER

July re, 1911

as well as on the Isthmus of Panama, it
is well nigh impossible to get any ac-
curate data as to the net saving resulting
from the specification method of pur-
chase. Buying fuel in this way results
in a number of benefits, one of the most
marked of which is that the quality of
the material delivered is much less vari-
able than when purchased at a flat price.
This means fewer operating difficulties,
more general satisfaction and better econ-
omy. Some of the plant engineers state
that by means of the analyses they can
more easily check up their coal consump-
tion and compel the fireman to be more
careful. The Government has been also
benefited in many cases since the in-
auguration of the coal-inspection work
as lower-priced fuels have been sub-
stituted; in one plant alone there is a
saving of nearly S800 per month.

Most of the coal-inspection work is
carried on in Washington, where a labora-
tory for the analysis of inspection sam-
ples is maintained. The experimental
work to be described is for the most
part carried on at the Pittsburg testing
station of the Bureau of iVlines.

Laboratory invesitigations have been
made of the fusibility and clinkering
properties of coal ash and chemical and
mineralogical e.xaminations are being
made of the ash in coal as it occurs in
the coal and in the clinker to study the
effect of the distribution of the ash in
the coal and the influence of the com-
ponent substances upon the clinkering
tendency. The results obtained indi-
cate that the composition of the clinker is
much more uniform than that of the ash.

Boiler feed-water treatment is also be-
ing studied and while this is not a fuel
problem per se, its bearing on the eco-
nomical use of fuel in steam-boiler prac-
tice is evident. The present plans in-
clude a study of the scaling properties
of various waters under temperature and
pressure conditions such as are met with
in practice, as well as the effect of the
different methods of treatment. Such a
study should furnish an explanation for
the corrosive or pitting action of certain
classes of waters, concerning which there
is a lack of reliable information.

Because of the rapidly increasing pro-
duction of petroleum, the scarcity of fuel
and authentic information on the oilfields
or the oil itself, the Government has
published certain bulletins concerning
the geology of some of the fields and
the statistics of production. To meet a
need for more complete information the
Bureau of Mines, in 1907, began a study
of the commercial value of the petro-
leums of the United States. Inasmuch
as the California fields promised so much
in the way of large and continued pro-
duction and furnished a fuel so peculiar-
ly adapted to use not only in stationary
and locomotive practice but also in the
navy and merchant marine, they were
made the first subject for study.

Among the other studies of coal may
be mentioned the investigations as to its
chemical composition; experiments to de-
termine the nature and quantity of vola-
tile matter evolved when various coals
are heated to different temperatures and
at various rates of heating; tests to as-
certain the deterioration of coal under
various conditions of storage, and an
investigation of the factors affecting the
rate of formation of carbon monoxide.-

Of the chemical composition of coal
but little is known today beyond the
information imparted from the usual
ultimate analysis which gives simply the
elements involved and the proportions of
each. The isolation of some of the con-
stituents of coal is also being investigated
and a number of different substances
have been obtained. By the use of inert
solvents it has become possible to ex-
tract as much as 35 per cent, of the
original coal. The evolution of vola-
tile matter from coal under various con-
ditions of temperature and rates of heat-
ing is frequently of considerable im-
portance in the economic utilization of
fuel, and tests have been made to deter-
mine the quantity and composition of
the gases evolved from various coals
when heated to temperatures varying
from 400 to 1000 degrees Centigrade.
The data thus obtained have been pub-
lished in Bureau of Mines Bulletin No.
1, entitled "The Volatile Matter of Coal."

Tests of coals from the New River and
Pocahontas districts to determine their
deterioration under various storage con-
ditions are of special interest, and analy-
ses indicate that coal stored in sea
water or fresh water does not deteriorate
to any appreciable extent, and that these
types of coals stored in the open air
even under severe weathering conditions
do not lose more than 1 per cent, of their
heat value in a year. Similar tests are
in progress upon coals stored in widely
separated localities and reports will be
made later. .^ thorough study is being
made of spontaneous combustion in fuel.
Through a circular letter a general in-
quiry has been made among coal con-
sumers for data of actual experience in
the matter for correlation and study. .\
study is also being made of the funda-
mental reactions involved, the rate of
oxidation at different temperatures, the
behavior of sulphur, the heat produced,
etc., and several serious cases in actual
commercial practice have been investi-
gated on the ground.

The formation of carbon monoxide
from carbon dioxide and carbon at dif-
ferent temperatures and gas velocities
has a direct bearing on the combustion
processes of a gas producer, as does al-
so the dissociation of steam when passed
through a bed of incandescent carbon.
It has been found that the rate of forma-
tion of carbon monoxide increases
rapidly as the temperature rises, thus
indicating that from this standpoint alone

it would be desirable to operate pro-
ducers at as high temperatures as pos-
sible. The results of these investiga-
tions have been published in Bulletin
No. 7, Bureau of Mines, entitled "Es-
sential Factors in the Formation of Pro-
ducer Gas."

Supplementing the laboratory investi-
gations on fuel, tests are being conducted
with larger apparatus or on commercial
equipment to determine their practical
application.

Extensive investigations have been
made on the briquetting qualities of vari-
ous fuels, and experiments on anthracite
and bituminous coal, lignite and peat.
Much of the earlier work was done to
determine whether the higher grades of
coals could be so improved by briquetting
as to justify the cost of the work, but it
has generally proved unprofitable.

There are in some parts of the coun-
try immense deposits of lignite where
other fuel is obtainable only by long
hauls; these raw lignites contain a large
percentage of water and upon exposure
to the atmosphere they tend to slack or
disintegrate, making them unsatisfactory
for many purposes and especially when
they are shipped over considerable dis-
tances. Could these fuel deposits of
lignite be so briquetted as to hold their
form during handling and storage and
with a material decrease of moisture
content, it would be of great advantage
to many consumers of fuel. The more
recent briquetting work aims to overcome
these objections.

The present equipment of the briquet-
ting plant consists of an English machine,
which is suitable only for fuels requiring
a binder, and a German lignite machine
of heavy construction. The lignite ma-
chine is used in Germany with great suc-
cess for briquetting brown coal; the press
is of the open-mold type and is driven
by a direct-connected steam engine; it
has a capacity of from 2' j to 3 tons per
hour and develops a pressure on the
briquet of from 14.000 to 28,000 pounds
per square inch. This press is only
adapted for those varieties of peat and
lignites which contain a sufficient quan-
tity of natural binder. The material to
be briquetted must be dried to contain
not more than 15 per cent., or less than
5 per cent, of water, the exact percent-
ages necessary varying with the different
lignites. The tests have been made on
samples of lignites coming from Texas,
North Dakota and California; the ob-
ject being to determine if American
lignites could be briquetted without an
artificial binder under the same condi-
tions as prevail in Germany for briquet-
ting brown coal. The briquets were made
elliptical in one section and rectangular
in the others, with dimensions approxi-
mately 6'4x2'Ixl inch and with an av-
erage weight of approximately a pound
each. As a result of these tests it was
found that briquets could be made with-

July 18, 1911

POWER

95

out the use of binding material from the
lignites of the three fields investigated.
The briquets from the California fuel
were strong and firm and withstood
handling exceptionally well and resisted
the effects of the weather for several
months. The briquets made from the
North Dakota fuel were also satisfactor>-
so far as form and strength were con-
cerned, but did not withstand the ef-
fects of weather so well as those made
of California lignite. Material from the
Texas field was briquetted only with con-
siderable difficulty and the briquets ob-
tained were weak in structure, poor in
form and did not resist the effects of the
weather at all. Tests of the latter, how-
ever, should hardly be considered com-
plete, as some of the samples shipped
to the bureau were entirely used up be-
fore satisfactory results had been
reached. The indications are that Texas
lignites and some samples of North
Dakota lignites would require the use of
binding material to produce commercial
briquets. These tests also show that
the reduction of the moisture in the
briquetting process increased the heat
value of the briquets obtained from 37
to 54 per cent, above that of the raw
fuel, and increase is of great importance
to the consumer as a greater efficiency
is obtained from the combustion of fuels
of high heat value than from those of
lower heat value. The experiments have
also conclusively demonstrated that the
briquetted lignite withstands the effects
of weathering several months longer than
the raw fuel as the moisture content
is reduced to a stable condition in the
process of briquetting. It is expected that
further tests will be made with this equip-
ment on other lignites of the country.

During the past year briquetting experi-
ments have been made on a sample of
Philippine Island coal, which, while in-
ferior to the best of American coals, is
of interest because it offers a local supply
of fuel to the Philippines, where the
price of coal is high, and in the briquetted
form It may provide a supply of steamer
fuel to vessels touching at ports on these
islands. Excellent briquets have been
made from this fuel, but the cost is high
on account of the large percentage of
binder required.

Experiments on washing and coking
In beehive coke ovens have demonstrated
the possibility of coking coals which have
^cen considered as noncoking, but no
"rk along this line is being carried on
- it is felt that further experiments with
■■ens of the beehive type are not of
ufficient value to warrant their continu-
ance.

During the past few years the intro-
duction of gas producers for power pur-
poses has created a new field in power
development and has made possible the
generation of power, even in small units,
with a very small fuel consumption. The
development of the power gas producer

promises to be the means by which large
quantities of low-grade fuels may be
successfully and economically utilized.
At the time the fuel-testing work was
inaugurated very few power-producer
plants were operating on anthracite coal
only, but to demonstrate the possibility
of using practically all grades of fuel
of any commercial value the producer-
gas investigations were undertaken. Over
160 tests were made on a great variety
of fuels and in general with very satis-
factory results. Subsequent tests were
made when special attention was given
to the utilization in gas producers of
low-grade fuels such as bone coal, wash-
er>' refuse, peat, lignite, etc. Although
many of these tests gave results which
would hardly warrant at the present time
the utilization of the poorer grades for
commercial purposes, yet they did show-
that fuel of this type can be readily gas-
ified and that the quality of the gas
produced is nearly equal to that made
from marketable coal.

The realization of the lack of exact
knowledge of furnace requirements re-
sulted in the decision to separate the
boiler and furnace problems and take up
the study of the latter.

For this purpose the bureau now has
at the testing station a specially con-
structed furnace and combustion cham-
ber. A Murphy mechanical stoker with
grate surface 5x5 feet located about 35
feet from a hand-fired Heine boiler, has
a firebrick-lined tunnel or combustion
chamber proper of the boiler setting.
This tunnel has a cross-sectional area
about 3x3 feet with an arched roof. When
experiments are to be conducted in this
long chamber the space between the top
of the bridgewall and the tile roof of the
Heine boiler furnace is bricked up. The
fire- and ashpit-door openings of the
hand-fired furnace are also sealed and
the gases from the combustion of the
coal in the Murphy stoker pass through
the tunnel and enter at the side and
near the rear of the boiler setting. After
entering the combustion chamber of the
boiler the gases then pass over the heat-
ing surfaces in the usual manner.

The problems being studied in this
equipment are those connected with the
fundamental principles of combustion.
Engineers who have any considerable
amount of work with furnaces for any
purpose realize that to secure efficient
and smokeless combustion of a coal, the
combustible gases must come in contact
with the air supplied and mix with it,
and burn before they come in contact
with surfaces which will reduce their
temperature below the ignition point.
More combustion space is required when
burning a coal high in volatile matter
than when burning an anthracite or semi-
bituminous coal, but as to just what
space the different kinds of coals do re-
quire for various rates of combustion,
there are few valuable data.

The work now planned for the long
combustion chamber includes tests with
each of several typical coals at varying
rates of combustion. In these tests the
effect of the following-named factors up-
on the space required for complete com-
bustion are being studied:

Nature of the coal, rate of combus-
tion, supply of air, rate of heating fuel,
rate of mixing volatile combustible and
air.

The completeness of combustion is
determined by the gas analyses. Pro-
vision is made for taking samples at sev-
eral -oints in a plane perpendicular to
the longitudinal center line of the tun-
nel, at the center of the bridgewall, and
in similar planes every 5 feet from the
bridgewall to the end of the long cham-
ber. At these same cross-sections tem-
peratures can also be taken with optical
or radiation pyrometers, or with thermo-
couples where the temperature is not too
great for them; holes are also available
for noting the length of flame or for tak-
ing other observations. At the present
time experiments are being made with a
semi-bituminous coal, of which it is nec-
essary to take about 35 simultaneous
gas samples, which must be analyzed
not only for CO:, CO and O, but also
for hydrogen and hydrocarbons. When
coals of the high-volatile bituminous
class are used it will probably be neces-
sary to materially increase the number
of such samples.

In connection with the preliminary or
calibration work on this long combustion
chamber some interesting observations
were made as to the relative value of an
air space and of asbestos as a means for
heat insulation. These observations are
set forth in Bulletin No. 8, of the Bureau
of Mines, entitled, "The Flow of Heat
through Furnace Walls."

In addition to this long combustion
chamber work the bureau is called upon
to make tests or conduct special investi-
gations for other bureaus or departments
in their own plants.

Some special problems along steaming
lines have also been taken up at the
testing station, among which is a study
of the effect of certain features of fur-
nace construction upon the smoke pro-
duction in a hand-fired, return-tubular
boiler furnace. This work has not been
entirely completed but the results so far
obtained indicate that a high-volatile coal
can be burned at ordinary rates of com-
bustion in such a furnace if steam jets
are used for a short time after firing,
without violating the smoke ordinances.

The policy of the bureau now is to
carry on experimental work for the pur-
pose of studying fundamentals.

It is essential that the basic princi
pies of the combustion processes of fuehi
be more definitely determined and it is
believed that the tests now in progress
will bring to light much information alonf;
these lines.

96

POWER

July 18, 1911

in 1 ^

O- il

D<

^ L# d 1 ^ A^i ^^^ J. 1 t

I

Correcting Low Power Factor
with Synchronous Motors

It lias been pointed out by several
writers in Power how the bad effe-^ts of
a heavy "lagging-current" load 1 an be
offset by the use of synchronous motors
running on the same line, with their
field magnets overexcited. When a
synchronous motor is thus operated, it
takes from the line a "leading" current
which offsets, to a greater or less extent,
the lagging current caused by induction
motors and other highly inductive ap-
paratus and causes the current which
actually passes through the generator
v.'indings at the station to lag very much
less than it would without the synchro-
nous motors in circuit.

This application of the synchronous
motor is increasing very rapidly and a
great many such installations have al-
ready been made. For example, two
machines of 1650 kilovolt-amperes capa-
city each are in operation in the Buffing-
ton substation of the Illinois Steel Com-
pany, where they work on the low-ten-
sion circuit which supplies an induction
motor load in the mills of the Universal
Portland Cement Company. The good
effects of these machines are indicated
by the following readings taken at the
generating station and the substation
simultaneously:

ilolors Motors
Off On

Kilowatts iixlicated at main

station busbars 6100 0400

Kilowatts indicated at sub-
station busbars 5800 G1.50

Voltage at substation low-
tension busbars 450 475

Power fastor at main station

busbars 74% 91.7%

Tile full-load current was maintained in the

low-tension circuits of the substation with the

synchronous motors on and oft.

In the Buffington substation the syn-
chFonous motors do not drive any load,
but it is not necessary to have them run
free. A machine installed for the same
purpose in the factory of the Chalmers
Motor Company, Detroit, is utilized to
drive an air compressor in addition to
correcting the power factor of the power
circuit. Before the synchronous motor
was put in, the voltage drop in the low-
tension circuit was so great that a 68-
kilowatt boosting transformer had to be
installed to keep the voltage high enough
for the satisfactory operation of the in-
duction motors which drive the factory
machinery. The power factor was so
bad, however, that it was found advis-
able to put in the synchronous motor;
its operation has raised the power fac-
tor from 68 to 95 per cent, and corre-

spondingly improved the regulation of
the whole system. This machine is il-
lustrated in the accompanying picture.
The usefulness of the synchronous
motor as an improver of the power fac-
tor of a circuit or system is not restricted
to long lines nor to extensive distribu-

average power factor of the system was
only 64 per cent.; the use of the motor
has raised the average power factor to
about 85 per cent. This motor runs en-
tirely free.

Dozens of similar cases could be cited,
but the three here outlined are suffi-
ciently typical to indicate the real prac-
ticality of using synchronous motors for
counteracting the objectionable effect of
induction motors on the power factor of
a system. In laying out new motor-
driven factories and industrial establish-
ments using large numbers of motors, i:
should be the policy of the directing en-
gineers to arrange for driving as manj
machines by synchronous motors as pos-
sible, and this will undoubtedly become

Synchronous Motor of 300 Kilovolt-amperes Capacity Driving an Air Com-
pressor AND Serving as a Rotary Condenser

tion systems. A 300-kilovolt-ampere
machine is in use at the Saxony Worsted
Mills, Bemis, Mass., in the same room
with the generators which supply the
system, which is all located within a
radius of a few hundred feet. The total
generating equipment is rated at 1050
kilowatts and supplies current to induc-
tion motors almost exclusively. The
load variations are such that before the
synchronous motor was installed the

a recognized plan of design. .Machines
that can be operated continuously at a
reasonably steady load and those which
can be shut off without having to shut
down the motor can be as conveniently
and efficiently driven by synchronous
motors as by the other kind.

For the illustration and the facts re-
lating to the three installations briefly
described herein we are indebted to the
General Electric Review.

July 18. 1911

POWER

97

The Maintenance of Electric

Circuits

By W. T. Ryan

Where the quality and design of the
apparatus and accessories for the gen-
erating plant and the substations have
been selected with regard to their re-
quirements and are afterward intelli-
gently operated, almost all of the troubles
which now affect the continuity of ser-
vice may be charged to the line.

Though the maintenance of overhead
lines is comparatively easy as a rule,
owing to the ready accessibility of such
lines for inspection at all times, the ex-
posure of the lines to the action of the
elements subjects them to a high rate
of depreciation. Continuity of service
cannot even be approximated with over-
head lines in a distribution system of
considerable extent. No matter what
precautions are taken or how good the
construction, the service is sure to be
interrupted at almost any point of the
system at one time or another.

The principal causes of trouble are
open circuits, grounds, short-circuits and
those circuit changes which produce os-
cillations. These are directly or indi-
rectly traceable to weak insulators, de-
fective pins, burning of poles, lightning,
etc.

The various forms of lightning ar-
resters and the methods of locating
grounds, crosses and short-circuits, have
been covered by the writer in previous
articles.*

Lightning arresters should be installed
on all main lines for the protection of
station apparatus and transformers. All
branch lines should be protected by at
least one set of arresters. Where the
line is long or there are several trans-
formers to be protected there should be
several arresters and these should be
properly grounded, because poor ground-
ing renders the operation of the arrester
uncertain and often defeats the purpose
of its use. Regular inspection of all
lightning arresters should be required
and additional inspections should be
made after every heavy electrical storm.

The choice of insulators depends prin-
I cipally on the voltage, and their mechan-
; ical strength and the locality through
which the line passes should be given
very careful consideration. In a lo-
cality where, for example, fog occurs at
(the same time or alternately with dust,
I the insulators are sure to develop trouble.
An examination of a large number of in-
' sulatnrs which had to be removed from
a certain line showed that the dust with
which they were coated was thickest in
the still air spaces and was as thick on
the vertical as on the horizontal sur-
faces. Where fog and dust do not oc-
cur together there is not nearly so much

•NoTPrntx-r 10 nnrl \oTonit)^r 17. lOOR.
«»<1 April .I. iniH

trouble with the insulators. In some
cases it may be necessary to shut down
one to three times during the dust sea-
son and clean the insulators. Insulators
tested for 120,000 volts, water test, for
one minute, have been known to give
trouble in less than a month after being
placed on a 40,000-volt line. Other types
which had stood 40.000 volts, water test,
for five minutes, have been found un-
satisfactory for 13,000-volt city service.
This merely shows that insulators which
are successfully tested at abnormally
high voltages before they are put into
service may cause trouble when on the
line.

Conditions of transmission may be con-
sidered good if, for continuous use only,
1 per cent, of the insulators have to
be replaced each year.

It was found that where the insulators
were giving trouble on a line operating
at 40,000 volts, reducing the pressure
to 30,000 volts did not produce a corre-
sponding or an immediate decrease in
the number of insulators broken per
month. The total number remaining
seemed to be in more or less of a weak-
ened condition, and they continued to
break down after the line pressure was
reduced, though after a certain period
of time the breakage per month was
reduced.

The charring of wooden pins is a
source of much trouble on high-tension
lines. In some localities the leakage over
dust-covered insulators will destroy the
pins in from one to three months. This
may be remedied by placing a metal
short-circuit around the pin, though a
better plan is to use metal pins. The
initial cost is only about I '4 times that
of wooden pins, and they are cheaper in
the end because the cost of maintenance
is practically nothing. Mold on the
thread of wooden pins, so often noticed
where a line passes through a marshy
place, can be avoided only by the use
of metal pins.

The service given by wooden pole-line
construction is subject to interruptions
by falling and burning poles. The de-
cay of poles can be greatly lessened by
continual and thorough inspection.

The old idea that poles of a kind of
wood suitable for the soil in which they
are set should last from 15 to 20 years
has caused much serious trouble.

Engineers are very often prevented
from buying poles early enough because
of the interest charges on them from the
day they would be paid for until the time
the wires are strung. The result is that
the poles are put in green, and unless
they are treated later on they will soon
decay. Whenever possible, seasoned
poles should he obtained. Their life will
be much increased by treating the butts
with creosote before setting them. Green
poles, however, should not be creosoted
before being set. The butts should be
treated after the first dry season and re-

treated about every second season there-
after, depending on the material used
and the condition in which the pole is
found. This after-treatment may be car-
ried out by digging away the earth from
the pole for about 18 inches below the
ground level and treating the pole sur-
face up to a point about 18 inches above
the ground. The ground level should
then be raised by banking earth around
the pole. The cost of this treatment will
usually be considerably less than one
dollar per pole. At the same time the
butts are treated the pole tops, gain
cracks and ends of the arms should be
painted.

If the methods just outlined are care-
fully followed, a wooden pole line will
last about 25 years.

The burning of poles at the ground
has caused many interruptions, even
where the line was patrolled every day.
The remedy is simply a question of per-
Bistence and expense in keeping the
right-of-way cleared of all growth. Even
with a wide right-of-way kept cleared,
the wind may carry heat and sparks from
a fire to the line. Several cases are on
record where the heat from a forest fire
along a pole line was not great enough
to harm the poles or cross arrows, but
did cause large numbers of the glass in-
sulators to crack and fall to the ground.
Porcelain is less affected by heat than
is glass and it is more durable mechan-
ically.

Underground Lines

Underground lines are relieved of most
of the troubles that beset overhead lines;
therefore, continuity of service may be
more nearly approached. Sleet storms,
high winds, in fact, nearly all causes
of breakdowns in an overhead system,
are harmless when the wires are under-
ground. The maintenance of underground
lines installed according to approved
methods is very simple and the necessity
for repairs much less frequent than on
overhead lines. However, when trouble
does occur it is usually of such a char-
acter as to require more expense and
more time to make the repairs.

Water is the arch enemy of under-
ground lines, and some method of drain-
ing a conduit is always necessary. Very
often the ducts are laid at a slight slope
toward the manholes and the water al-
lowed to gather there is pumped out oc-
casionally or. belter still, is carried off
by connections to the sewer. If no water
can enter the conduit except the moisture
in the air, it is unnecessary to have a
sewer connection.

Gas sometimes penerates the conduits
through the walls of the manholes and
even through the ducts themselves when
there are gas leaks nearby. In New
York City so much trouble was experi-
enced from gas and water that it was
found necessary to connect the manholes
by 6-inch pipes through which a cur-
rent of air is continually blown. This

98

POWER

July 18, 1911

drives out the gas and dries up the
water deposited by condensation. Water
from the street is kept out by the use
of perfectly tight manhole covers. This
system is, of course, very expensive and
cannot be considered unless a large num-
ber of ducts is laid. Ordinarily, the gas
can be removed by ventilation through
the covers themselves by simply piercing
them with holes. Auxiliary pipes lead-
ing up to the tops of neighboring build-
ings are also advantageous.

The failure of the insulation of cables
near points where connections are made
between overhead and underground lines
is often a cause of trouble (especially
where the underground lines are short)
from lightning. Lightning arresters
should be provided near the cable poles.
Where the underground system extends
over a large area, however, this trouble
is not so frequently experienced.

LETTERS

Adjustijig a Belted Exciter

The exciter which supplies the field
winding of an alternator in our plant is
belt-driven from a pulley on the end of
the alternator shaft. Consequently,
when the alternator is shifted on its base
to tighten the belt, the exciter must be
adjusted on its base also, in order to keep

frames as shown in the accompanying
sketch; with this arrangement the exciter
is kept at the same distance from the
alternator while the latter is being ad-
justed on its base. Whenever it is neces-

Water Tank Signal Swstem

The alarm illustrated here is as
reliable as one could be made, because
if the alarm bell did not ring for any

'Carbon Pencil
pre55ed againsf

Float Rod by a Spring

T

■Con tad Disk

Laihps

€H-0^

•Mr. Woolman's Water-tank Signal
System

sary to adjust the tension of the exciter
belt independently, that is done by means
of the handwheel and screw W, which
shortens or lengthens the strut. The iron
pieces A and B are bolted solidly to the
wooden bar, but the long strap C is
bolted to the bar through slots, as shown

reason, the lamps would show whether
the water was high or low. The float
rod slides through a fiber block on which
are mounted the high-water contact C h,
the low-water contact C / and a common-
return contact consisting of a carbon
pencil pressed lightly against the rod by
a spring.

The system is entirely automatic, no
switch manipulation being required. When
the water is high, the circuit from the
lighting circuit to the solenoid S is closed
through the lamp H ; when it is low, the
solenoid circuit is closed through the
lamp L. In either case, the solenoid

Adjustable Strut for Maintaining Correct Tension on Exciter Belt

its belt at the right tension. In order to
avoid the bother of adjusting the two ma-
chines on their bases by turning the two
adjusting screws a little at a time al-
ternately, I have rigged up a distance

in the plan view; the bolts through these
slots are slackened when the length of
the strut is to be changed and set down
tight after the adjustment is made.

Charles H. Lynch.

strut between the alternator and exciter Lewes, Del.

draws its plunger down and closes the
hell circuit at B. When the solenoid cir-
cuit is open, the contact at B is kept open
by the spring above the lever.

N. E. WOOL.VtAN.

Danbury, la.

July 18. 1911

POWER

The Effect of \'arying the

Supply of Steam to a Gas

Producer*

By E. a. Allcut
The experiments recorded in this paper
were performed with a small gas pro-
ducer at the University of Birmingham.
The chief object was to determine the
influence of varying quantities of steam
on the general working and efficiency of
a producer plant of small size. The
supply of air to the producer was, there-
fore, kept as nearly constant as possible
in all the trials, while the steam supply
was varied from nothing to a maximum
of 1.14 pounds per pound of coal. In
order to avoid complication and to elimi-
nate all uncertainties of measurement
which must necessarily arise from the
presence of tar and volatile hydrocar-
bons, as well as to obtain a fuel as nearly
approximating to pure carbon as pos-
sible, anthracite pea coal was used
throughout the trials.

The steam required for the process was
generated within the producer, so that
the general conditions closely resembled
those under which a modern suction plant
works; the sole exception being that the
draft was produced by a fan instead of
by engine suction. The conditions were
thereby kept fairly steady throughout
each trial. A good deal of uncertainty
seems to exist among the makers and
users of gas producers respecting the
amount of steam that is required to give
maximum efficiency and best all-round
'rking, and it was hoped that these
•Is would clear up a good deal of that
ertainty. A series of similar trials
■c performed in 1906 by Messrs. Bone
! Whceler,t on a 2500-horsepower gas
nt. It was felt, however, that the con-
ons under which those trials were
r formed were vastly different from
-e under which most of the smaller
lilts work, and that it was necessary
tn repeat them on a small plant with
nonbituminous fuel, to gain a more ex-
act idea of the influence of steam upon
producers of small capacity.

Reactions tn the PRonucER

The true nature of the combustion of

•olid carbon is still, among scientists, a

vexed question. Some chemists hold that

with excess of carbon the combustion

•Almtrncl nt a papor ronrl tx-forp the InftI
iii'lon of Mfrtianlrnl Knitlnprr" of fJrnnt

proceeds in two stages: first of all with
the production of carbon dioxide,

C ^ 0= = CO; (1)

and then with the reduction of the dioxide
on further contact with carbon,

C0= -^ C = 2C0 (2)

Others maintain that the combustion pro-
ceeds in a single stage, direct to car-
bon monoxide.

2 C + O: = 2 CO (3)

At the bottom of a gas generator, how-
ever, the carbon is never in excess, so
that the author is of opinion that the first

heat, it is advisable to maintain the high-
est temperature consistent with prac-
tical working. The high percentage of
CO. in Mond gas is due to the predomin-
ance of the reaction expressed by equa-
tion (5), which results from the low tem-
perature and excessive steam supply nec-
essary for ammonia recovery. This lat-
ter consideration does not enter into the
practical working of plants of less than
2000 horsepower, so that in small plants
the steam supply can be cut down to
any point consistent with the nonforma-
tion of clinker.

The actual conditions inside the gen-
erator are by no means as simple as
would appear from the preceding reac-
tions. When CO and steam are both
present in a gas producer, the following
reversible reaction may be set up:

CO + H,0±5:CO, -l-H, (6)

This reaction, which takes place at tem-
peratures above 932 degrees Fahrenheit,
also depends for its balance upon the
temperature. At high temperatures ( 1832

Temperature

COXHjO

Temperature

K.

CO.XH,

786 C. (1447 F.)
.S.S6 C. (1627 F.)
986 C. (1807 F.)

0.81
1 13
1 . 54

10S6 <;. (19S7 F.)
120.5 C. (2201 F.I
MO.i C. (2.561 F.I

1 95
2.10

2 49

two reactions probably take place within
the generator. However this may be, the
final chemical and thermal results of the
combustion are the same in each case.
When steam is admitted with the air
it may react on its own account with
the carbon in the following ways:

C -f H.O = CO -f H= (4)

C -f 2H..0 = CO: + 2H, (5)

Bo[th of these reactions absorb heat,
the former to the extent of 4300 B.t.u.
per pound nf carbon, and the latter to
that of 2820 B.t.u., so that each of them
has the practical advantage of reducing
the temperature of the producer. It has
been found* that at a temperature of
1112 degrees Fahrenheit and under, the
latter reaction takes place, but at tem-
peratures above 1832 degrees Fahrenheit,
reaction (4> is more likely to occur. At
temperatures between 1112 and 1832 de-
grees, the two take place simultaneously,
the predominance of cither being en-
tirely a function of the temperature. It
is clear that as equation (4) gives the
richer gas and the greater ab.sorplion of

•I'roiliiccr (Jan." Dowaon and Ijirter. page

degrees Fahrenheit) the left-hand side
predominates and at low temperatures
carbon dioxide and hydrogen arc formed.
ki any temperature between 932 and
1832 the product of the percentage vol-
umes of CO and steam bears a con-
stant ratio to that of the C0= and hydro-
gen. Oscar Hahnf gives the values in
Table 1 for this ratio at different tem-
peratures. As the ratio rises with the tem-
perature, the addition of steam, lowering
the temperature, will cause a change in
the opposite direction. The oxidation of
CO, however, liberates heat and raises
the temperature, thereby tending to check
the action. The conditions for stability
arc always in the direction of high tem-
perature and the consequent formation
of CO.

Reaction (2> also is a reversible reac-
tion and depends on the temperature. At
1790 degrees Fahrenheit. Boudouardf
found that the percentages of CO and
CO; in equilibrium with solid carbon
under atmospheric pressure were 99 and
1 lespectivcly ; while at 1497 degrees

^/.rilnrhilfl fiir /'/l»/«(«nH«rftr Chrmlr. 10(13.
t,4nnfl/ni dc Chimic el Ac I'liu'lgiir, 1001.

100

POWER

July 18, 1911

they were 90 and 10, and at 1090 de-
grees they became 20 and 80. General-
ly, then, increase of temperature favors
the formation of CO, giving richer gas
and higher efficiency, and at lower tem-
peratures a higher proportion of CO.- is
obtained.

The steam supply to the producer has
then an important effect, as it controls
the temperature at which these reactions
take place. If the steam supply is in-
creased above a certain amount per pound
of carbon, the temperature and efficiency
of the plant both fall. If, on the con-
trary, the supply is cut down too low,
the temperature rises, gives bad working

\J Feed

nir

]i-l

Fig. 1. The Generator

and increased heat losses and yields a
poor gas. There is then clearly a cer-
tain proportion of air and steam that will
give maximum efficiency, and it was one
of the objects of these trials to find that
point.

Description of Experimental Plant

The entire plant was made in the work-
shops of the University of Birmingham,
and is illustrated herewith. The generator,
Fig. 1, consists of a wrought-iron shell
lined with firebrick. The inside diam-
eter of the lining is 10 inches and its
hight 25 inches. The joint between the
bottom of the lining and the wrought-
iron angle ring that supports it was care-
fully made with fireclay and the space
between lining and shell rammed with
the same material. Notwithstanding these

precautions, some of the air found its
way up to the top of the generator
through cracks in the lining and pro-
duced a certain amount of C0= by com-
bustion of CO. This accounts for the
high percentage of CO:, in the earlier
trials, and partly for the low calorific
value of the gas.

The fuel level in the generator was
kept as constant as possible by the dis-
tributing bell shown in Fig. 1. The

gas is forced to pass zigzag fashion from
one end of the washer to the other. The
washer is partly filled with water which
is picked up by the small vanes on the
disks marked C and dashed intimately in-
to contact with the gas. The large area
of wetted surface thus presented to the
gas makes this type of washer very effi-
cient as a cooler.

The plant layout is shown in Fig. 3 as
arranged for a trial. The air was supplied

Fic. 2. Longitudinal and Cross Sections of Washer

conical coal valve allows the coal to be
charged into the producer without escape
of gas or influx of air. The grate con-
sists of a grid of wrought-iron bars, with
spaces of W inch between them, so that
no coal can fall through without burn-
ing. The grid is hinged at one end and
supported by a movable bar at the other,
so that it can be dropped at will and the
generator emptied through the cleaning
door. The vaporizer consists of a coil
surrounding the distributing bell in the
top of the chamber. The steam formed
at the expense of sensible heat from the
gas passes out at the top of the coil

iprTnq Wafer Tank

^ /^ ji >r Oenerator

by a motor-driven fan and its volume
was ascertained by measuring the drop
in pressure down a narrow tube (9 feet
long by 1 inch in diameter). The differ-
ential gage used for this purpose is
shown in Fig. 4. The large cross-sectional
areas at the top give a large movement
of the meniscus between the paraffin and
water for a small difference in pressure.
The movement of the meniscus was ob-
served on a scale engraved in a mirror
at the back of the gage, and a calibration
curve prepared by putting the tube in
series with a standard gas meter and
observing movements of the meniscus

Fic. 3. Arrangement of Testing Plant

Fig. 4

and is conducted by a lagged pipe to the
ashpit.

The washer, Fig. 2, is of novel con-
struction. It consists of a cylindrical
shell, 18 inches in diameter by 48 inches
long, closed at the ends and traversed
by a shaft strung with thin disks of 17
inches diameter. This shaft is rotated at
76 revolutions per minute. The disks are
alternately pierced at the edge and the
center, as shown at C and D, so that the

for various rates of gas supply. The
same method was used for measuring the
gas produced. The amount of air was
adjusted to the required value by open-
ing or closing the escape valve in the
air pipe. The temperature and pressure
of the air supply were also observed.

The water was fed into the vaporizer
from a tank supported above the pro-
ducer by a spring balance, from the
readings of which the weigh*, and regu-

July 18, 1911

POWER

101

larity of the feed were ascertained. The
temperature of the water feed was taken
at regular intervals.

The coal was weighed out in lots of
7 pounds, a sample being taken at each
weighing. Each trial was started with
the generator full of coal and a level in
the hopper was marked. The weighed
lots of coal were fed into the hopper in
each case as soon as this level was
reached and at the end the surplus coal
was taken out and weighed, so that the
quantity used during the trial and the
regularity of feed were accurately known.

The reason for the adoption of so
small a plant was to enable us to test
it in a short time. The actual duration of
each trial was 4 hours, but the plant
was run for some 3 or 4 hours in each
case before any readings were taken, in
order to get conditions steady before the
trials were commenced. The steadiness
of the conditions was judged from the
constancy of temperature of the gas is-
suing from the producer. At the end of

Mahler bomb calorimeter. The heat value
of the gas, the heat lost in the washer
and the w-ater vapor entering the pro-
ducer with the air were calculated from
the observations. The heat values used
for this purpose were:

CO = 340.9 B.t.u. per cubic foot
H: = 343 B.t.u. per cubic foot
CH, = 1067 B.t.u. per cubic foot
The efficiency was in every case cal-
culated from the calorific value of the
raw coal and the higher heat value of the
gas, and includes the heat required to
vaporize the water feed. The heat in
the gas is also expressed as a percentage
of the heat in the coal, for the sake
of comparison.

Deductions fro.m Tests

The first noticeable point in these re-
sults is to be found in Fig. 5, which
shows that the percentage of hydrogen
in the gas did not increase with an in-
crease of water fed into the fuel bed
when the water exceeded 0.75 pound per

80

Bone and Wheeler x x

0.4 0.6 0.8 1.0

Water Feed per Pound of C<Jbl po~ci

FiC. 5. CO.MPARISON OF PRESENT TESTS WITH THOSE OF BONE AND WHEELER

each trial an electric-resistance thermom-
eter was introduced into the generator
through one of the poke holes and the
temperature was taken at the grate and
at intervals of 3 inches upward from
the grate to the top of the generator.

All readings were taken at intervals
of 15 minutes. The gas samples were
taken over mercury at intervals of 30
minutes and carefully analyzed in special
, apparatus. The volume of CO present
I was obtained not by absorption in cuprous
chloride but by explosion with air. The
CO. hydrogen and methane were all ex-

pound of coal. This corresponds, as
shown in Fig. 6, to the decomposition of
about 72 per cent, of the total weight of
water fed to the fuel bed. This result
is very important, as it shows that the
maximum amount of steam that can be
decomposed by anthracite at a tempera-
ture of about 1832 degrees Fahrenheit
is about 0.53.'^ pound per pound of coal;
see Fig. 6. It follows that there can be
no advantage, but only loss, in pushing
the steam supply much beyond I4 pound
of steam per pound of coal in small
anthracite gas producers. If this rate is

! ploded together and the contraction. COi greatly exceeded, the increased supply of
I formed and oxygen used were measured steam merely takes heat from the pro-
|ln the usual way. This method gives ducer and loses it in the washer. Large
three equations from which the respective quantities of steam are not necessary for
j volumes of the three constituents of the the prsvention of clinkering. The shallow

fuel bed in the producer tested by the
author, however, with its consequent high
mean temperature, resulted in the ad-
vantageous use of a higher proportion
of steam than could be economically
used in a producer having a deeper fuel
bed.

I gas can be determined.*

j The h»at value of the coal was in each

jcaie ascertained by combustion in a

■Till? eqnationn aro a.<i follow«:

jro + ill, + 2in,-OTyKPn used
V'O + JI'i + 2f 'n, -C-onlrartion
rn+ m.-^ffi, formed

The low percentage of hydrogen in the
gas throughout these trials was due to
the large quantity of air which had to
be used to keep the vaporizer at a suffi-
ciently high temperature to supply the
necessary amount of steam, owing to the
inefficiency of the steam coil. This re-
sulted, in a high ratio of air to steam

~^

^kt..

p... t 1

^0.1 _

1

,fo>i2l

>^

i>

ife^«v

/"A

s.

,^

^/\

1

■

vlO

V

1

/

1

0.6 a

■o

04 i.
I

0.2 o

04 0.6 08 10 1.2 "" *
Wof er. Feed per PounO of Coal «»»<.

Fig. 6. Effect of Water Feed Rate
UPON Decomposition

and the consequent presence of a large
quantity of nitrogen in the gas.

Combustion of Carbon

The most significant result of these
trials is that the percentage of CO: re-
mained practically constant, in spite of
the increasing feed of steam to the fire.
The high content of CO? in the trials
where little or no steam was supplied
was due, as explained, to a leakage of
air. Eliminating the 7 per cent, of COi
in the first trial as due to this cause, it
is found that the maximum rise during
the whole of the trials is merely about
2.5 per cent. It would naturally be ex-
pected that the increased supply of steam
would diminish the temperature inside
the generator and result in the production

^

—

-^

^•-

■~-~

•A

\

s'--

\

\

~<r

[^

=^E

\«

^

s\

\

I \

I

A

\

\\

\

Lett

rs r
■ to

ftr

hf If

Sti

K-

^:

\;

vN

\\

\

^^'-^

"^

0 3 6 9 IZ 15 18 2J 24 27 30
Dtstonce obove Grote, IncHes '*•»«

Fig. 7. Temperatures in the Fuel Bed

of increasing quantities of CO.-, from re-
Eciions (5). (6) and (7). This is ad-
mirably shown in the trials of Messrs.
Bone and Wheeler, where the CO3
(shown dotted in Fig. 5) rose from 5.25
per cent, at 0.45 pound of wafer per
pound of coal to 13.25 per cent, at 1.55
pounds of water per pound of coal.

Why docs not the same rise occur In
the author's experiments? It seems at

102

first sight that these experiments con-
tradict the theory laid down at the begin-
ning of this paper — a theory supported
by experimental evidence in the tests of
Messrs. Bone and Wheeler. The contra-
diction, however, is only apparent. At
the end of each trial the temperature of
the fuel bed was taken at equidistant
levels from the grate to the top of the
bed. Although the temperature curves
thus obtained (see Fig. 7) are somewhat
erratic, as might be expected, there is
one characteristic which is common to
all. The temperature keeps fairly con-
stant at about 1832 degrees Fahrenheit
(1000 degrees Centigrade) for a distance
of about 18 inches upward from the
grate and then falls rapidly to about 1112
degrees Fahrenheit (600 degrees Centi-
gr?de) in the next six inches or so. In
the first 18 inches, then, the combustion
of the carbon is obviously taking place
and all the heat is developed. Above this
point the steam begins to affect the tem-
perature and causes it to fall with ex-
treme rapidity.

Now, as has been explained, at a tem-
perature of 1832 degrees Fahrenheit, no
CO, can exist in contact with excess of
carbon. The large excess of oxygen at
the grate causes the carbon to burn to
CO2 with the evolution of large quan-
tities of heat and the maintenance of a
high temperature. The excess air burns
r?] higher up in the generator and main-
tains the temperature, but farther away
from the grate, the reduction of CO; to
CO and the endothermic steam reactions
begin to have the predominating effect on
the temperature. The first 18 inches,
then, may be termed the zone of active
combustion where, owing to the high tem-
perature, the gases produced are almost
entirely CO and hydrogen. There is above

POWER

reactions to seriously affect the composi-
tion of the gas and the efficiency of the
producer. This shows that in a generator
which has a shallow fuel bed, provided
there is no leakage, there need not be
more than 2 or 3 per cent, of C0= in
the gas. If more than this quantity is
present, it is due either to leakage or to
the use of too great a quantity of air
for the size of the producer. In the latter
case, the velocity of air through the fuel
is high and some of the CO. formed by
combustion in the fire zone escapes re-
duction to CO. The depth of the fuel
bed should therefore be cut down to the
lowest value consistent with practical
working.

In large generators a deep fuel bed is
necessary, as the larger sizes of coal
used in them do not pack as close as
the smaller pieces and the distribution of
air across the section of the fuel mass is
apt to be irregular. In such cases it
might even pay to have a secondary air
supply adm.itted some distance above the

July 18, 1911

ducer itself and the total heat in the coal
used during the same period.

It will be evident from Fig. 8 that the
maximum yield of gas occurred at a water
feed of about 0.75 pound per pound of
coal. This is near the point where the
maximum percentage of hydrogen was

0.2 0.4 0.6 0.8 1.0 l.t
Wo+er- Feed per Pound of Coal

t

1 1 ' ! M 1 1 1

obO

1 I^H*^^

>

£.

UMn_"

-^

""^

^^°

L^^^i 1 1

^;^

c

i

-

1

1

.y 40

1

-

0 20

s

£

•

\

_

1

02 0.4 0.6 0.8

Water Feed oer Pound of Cool

FiG. S. Effect of Water Feed Rate
UPON Gas Made

this about 6 or 7 inches of fuel bed in
•which the temperature is rapidly falling.
This would have its due effect in re-form-
ing CO, by reactions (5), (6) and (71
if it were not so thin. The shallowness
of this comparatively cool layer of fuel
does not allow sufficient time for these

0 0.2 0.4 0.6 0.8 IJJ i-c
Woter Feed per Pound of Coal '■^f

Fig. 9. Water Feed and Heat Effi-
ciency

grate. This would have the effect of in-
troducing another zone of active combus-
tion, in which the heat evolved by the
combustion of the secondary air to form
carbon monoxide would be available for
reducing the CO: coming from the grate.
The depth of the cool layer of fuel above
the active combustion zone would thus
be reduced and the re-formation of CO;
according to the reaction expressed by
equation (6) would be greatly diminished.

Heat Value of the Gas

The heat value of the gas is very low
throughout, as shown in Fig. 8. This is
partly due to the low percentage of
hydrogen which is the outcome of the
high ratio of air to steam. The nature
of the fuel also is accountable for the
very low percentage of CH. which has a
great influence on the heat value. It is
noticeable that the percentage of com-
bustibles in the gas regularly increases
until 0.7 pound of water per pound of
coal is reached, and then decreases agaih.
The heat value also reaches maximum
about this point.

Efficiency

The efficiency of the producer is taken
as the ratio between the heat generated
which does useful work outside the pro-

Fig. 10. Water Feed and Washer

obtained, and where the heat value of
the gas was highest. It follows, there-
fore, that the efficiency of the producer
reaches its maximum at this point. The
lower curve e,. Fig. 9, gives the ratio of
the heat per hour in the gas produced
to that in the coal used, expressed as a
percentage. The higher, Cz, includes the
heat necessary to vaporize the water
supply; the latter represents heat that
would otherwise be lost in the washer
and as it is taken from the generator it
should be credited to that source of sup-
ply. The higher value, e,, is, therefore, the
true efficiency of the producer.

The temperature of the gas leaving the
generator is shown in Fig. 8. The highest
temperature was attained in trial A (in
which no water was fed into the vapor-
izer), being about 750 degrees. A steady
fall was maintained with the increase in
water feed until trial D was reached,
when the temperature was about 550
degrees; after this, the temperature re-
mained fairly constant.

The washer loss is almost constant
from trials A to D. the fall being sim-
ply due to the drop in temperature of
the gas. After this point, however, it
rapidly rises, owing to the sensible and
latent heat carried over by the surplus
steam. The dotted line. Fig. 10. shows
the heat carried away by the gas alone.
The sharp upward slope of the latter end
of the curve shows the necessity for re-
generation where large quantities of
steam are used.

The longest electric railroad in .\ustria
is the 40-mile line running from Trient
to Male, and it ranks among the long
lines in Europe. It was built especially
as an electric road, and is narrow gage
using overhead trolley and working or
800 volts direct current. The motor cars
have four 50-horsepower motors, one on
each axle. Current for the line is taken ^
from the distant hydraulic station of
Sarca on 20.000 volts, this being reduced ;
in three substations along the railroad |
in order to feed the trolley wire. Freight
and postal cars are also used. — Scientific
American.

_ L

July 18, 1911

POWER

103

Pins in Loose Crank Pins

From time to time there have been
printed tales of "Loose Crank Pin Re-
pairs" which vary a little in detail, as to
how discovered, probable cause, etc., and
it has seemed to me about time a change
was made in the method of repair, which
in each case has been about the same.
The practice has been to drive a key half
in the pin and half in the eye of the
crank. The fact that this key takes the
form of a round pin, or pins, driven in or
of holes tapped and bolts screwed in,
makes but little difference, and "don't do
it" seems to me about the proper advice.

Most of these are temporary' jobs, to
help things along until "we get a chance."

Two Methods of Driving Pins in a
Crank Pin

I have seen a number of such jobs done,
and never knew one to pan out tight
long enough to pay for the labor spent
on it; and if the matter is looked into, it
will be plain why the job failed.

For instance, a pin is loose in the eye
A, and a hole is drilled in both pin and
eye, and the pin B driven in hard, con-
centrating the holding strain to the diam-
I efer of the pin li, which soon works loose.
I A second pin is driven at C, which only
I makes matters worse by concentrating
I the holding strain at fi and C, and it is
self-evident that this arrangement will
I not hold; and a triangular arrangement
of pins is no better.

In case the holes are tapped and the
pins are screwed in, matters are worse,
18 a few turns of the engine will bed
the top of the usually poor fitting threads
into each other, and the pin is still loose.
It goes without saying that a proper
repair consists of reboring the eye of the
crank in line with the shaft and shrink-
ing or driving in a new pin, and until this
i8 done, what is the sense of spoiling
the crank and eye and weakening it by a
half hole, or series of half holes?
Similar repairs have been made and

have held tight in crank eye and shaft
ends for a long time, and left things in
good order for permanent repairs, as fol-
lows :

A series of holes are drilled in the
loose pin with the edge of each hole
1/32 to 1 16 inch from the outside edge,
and a tight-fitting pin, with a slight taper,
driven into each hole, which will expand
the face of the crank pin out against
the eye while forcing the front side of
the pin close against the eye, keeping a
large amount of surface in contact with
the face. When this pin is removed for
permanent repair, the eye is in good con-
dition for reboring and is not permanent-
ly weakened by a series of gutters.

B. W. Robinson.

Dorchester, Mass.

Makeshift ^^tlve Repair

At an electric-railway power station
where I was employed, there occurred
an accident to a ,500-horsepower cross-
compound condensing engine, caused by
water in the cylinder.

The condenser is a jet with a vertical,
duplex, single-acting pump. Originally
this pump was fitted with a piston valve
for each cylinder, but one of the pis-
ton valves had been broken and a plain
slide valve substituted.

Both valves worked on the same stem
and the remaininc piston valve was made
to actuate the slide valve. This burdened
the piston valve so much that the pump
would frequently stop on account of the
valve sticking. I have known this to
happen as many as six or seven times a
day. By keeping a pinch bar handy and
prying the valve stem over the pump
would start off again. By this means and
the aid of the vacuum breaker trouble
was avoided for a long time.

One day. however, the pump stopped
once too often, the vacuum breaker failed
to operate and the engine was badly
damaged. The only remedy applied was
a new float to the vacuum breaker. I
would not be surprised to hear of the
same thing happening again, for the one

piston valve is still doing the work of
two.

Frederick M. Perras.
Mansfield, Mass.

Successful Isolated Plant

A good example of economical opera-
tion in a small isolated plant, together
with a demonstration of the value of ac-
curately kept records covering every de-
tail pertaining to its care and operation
was furnished recently when a central-
station solicitor submitted to the directors
ot a club a proposition to light the es-
tablishment.

Additions were contemplated doubling
the capacity of the existing equipment
and necessitating a large increase of the
power plant which now furnis'ies heat
for the building, the swimming pool and
bath water and light for the whole in-
stitution.

The plant consists of a 40-kiIowatt
125- volt generator direct connected to an
automatic horizontal high-speed engine
running noncondensing, and two 50-
horsepower horizontal tubular boilers
and accessories. Bath water is stored
in a tank 25 feet long, and 6 ftet in
diameter, and it must be kept hot day
and night the year round. Certain por-
tions of the building require heating
seven months out of the twelve and
light is required constantly.

The central-station man proposed to
handle the entire lighting load and quoted
a rate of 5 cents per kilowatt-hour, or
less than half the usual rate. By ac-
cepting this proposition the possibility
of reducing expense was suggested by
replacing the engineer with an unlicensed
man who would run the boilers at low
pressure merely for heating purposes.
Some of the directors of the institution
were stockholders in the electric company
and every effort was made to rush the
matter to an immediate conclusion.

The engineer, however, who was care-
fijl and painstaking, had complete rec-
ords of all facts pertaining to the op-
eration of his plant, covering a oeriod
cf five years. These included all fixed,
operating and maintenance charges as
well as detailed accounts of all supplies
and repairs, each charged to the proper
department. He knew to a quarter of
an hour how long the generator had
run each day in the year and what had
been the output as indicated on the
switchboard wattmeter. He had com-
plete informafinp as to the time live and
exhaust steam had been used and for

104

POWER

July 18, 1911

what purpose. In fact, no essential de-
tail was overlooked or slighted and his
figures, when presented to the directors,
convinced them they could not afford to
go outside their own plant for the re-
quired service.

The figures for one year's run are as
follows:

OPERATING .\ND MAINTENANCE
CHAItCJE.S

Engineer's salary S9M . 00

llelpcr's salarv 468 . 00

Coal, 420 tons at .Sa-.W 1,470.00

Water for boilers, 6.=>.000
cubic feet at "i cents

per 100 cubic foot 48 . 7.5

Total $2,922.75

KUPPMF.S

Supplies chargeable to
steam plant:
O'l, grea-se, wa-ste, pack-
ing, polish, etc .$7.'5.S2

Supplies ctiargeable to elec-
tric plant:
Lamps, shades, sockets,

fuses, etc 286 68

Total S360 . .50

Removal of ashes 30 . 00

Inspecting boiler 5 . 00

REPAIR.H

Engine, generator, switch-
board S2S.90

Boilers 179.24

Pumps, tanks and piping. . 187.66

Tools and hardware 9.66

Incidentals 9 . 04

Total $414.50

Interest at 5 per cent., de- 1

preciation at 3 per cent.
Insurance: at 0.5 per cent. \ Sn69 50

on S6,700, first cost of

plant. J

Total S4..J22.20

Extra for electric light from
central station:
2,510 kilowatt-hours at

12 cents S.i01.20

Clrand total S4.623 . 45

Engin'e Room Log for Sajie Ye.xh

Engine running (houre) 1 .847 . 2.'.

Generator output (kilowatt-
hours) 32,248.00

ExHAi'ST Steam

Hot-water service (hours) . 1 ,845 . 50
Building (houns) 1 .361 . 75

3,207.25

Live Steam

Hot-water service (hours). 2,287.00
Building (hours) 2.084.50

4,371.50

If the entire light load had

been purchased at the 12-

cent rate the cost would

have been

(32,248 X 12c.) + S301 . 20 - $4, 170 . 96
It same were purchased at

the new rate of 5 cents.

the cost for the entire ser-
vice would be

(32,248 -I- 2.510) X 5 cents = $1 ,737 . 90
Since the plant is operated

for light alone not more

than 25 per cent, of the

entire time the total oper-
ating expense divided b.v

4 represents the charge

to be made for light.

$4,322.25

^$1,080., 56

4
In favor of the Isolated

plant

$1,737.90 — Sl.OSO.. 56 $6.57.34

The absence of certain charges usually
included in schedules of this nature
should perhaps be explained.

Taxes are rebated.

No supervision or overhead charge
may be apportioned to the power plant
as the engineer is in complete charge

and responsible only to a house com-
mittee which serves without pay.

As it is not a manufacturing plant the
item of profit is not properly to be in-
cluded.

The above figures were submitted to
the directors and demonstrated to them
that light was a secondary consideration,
a byproduct of the heating equipment,
as it were, where the engine served as a
reducing valve between the boiler and
the heating system. On the basis of the
facts above set forth, new units were
installed which doubled the capacity of
the initial equipment.

T. D. Hayes.

Cambridge, Mass.

Trouble with Leaking Tubes

In May, 1909, a new boiler was in-
stalled in the plant where I am employed.
Three months after its installation the
tubes began to leak.

The boiler is made with but two sheets
and double-riveted lap seams. Below
the tubes there are two through stay rods

Pipe and Fitting Tester

It is necessary to occasionally test pipe
fittings and separators for leakage where,
fortunately, the city water system has a
pressure of 90 pounds per square inch.
Heretofore it was necessary to use a
pressure pump, but the pump cylinder
and plunger were too small to maintain
a pressure, due to leakage which occurs
sometimes in defective gaskets and tem-
porary bolting. I invented a device which
*orks to the Queen's taste and is a big
time saver.

In the cut is shown the whole system
attached to a small fitting. The upper
portion, handwheel, yoke^ stem and valve
were taken from a discarded 4-inch globe
valve. B is a compression cylinder, fitted
with a cup leather plunger C which is
attached to the valve on the end of the
slem. £> is a changeable plate to fit vari-
ous sizes of flanges and E is the fitting
to be tested. D may be blanked when
testing through the inlet pipe F.

The system is filled with water through
the pipe F directly from the city sup-
ply. Then with the valves G and H
closed and all joints tight, a partial turn
of the handwheel will raise the pressure
rapidly. / is a pressure gage.

If desirable to use the device on an
outside job, connect the pipe / to the
job, fill with water through the %'alve G,
which is then closed, ard open the valve
H. Then turn the handwheel until the

J

Section of Pipe and Fitting Tester

which I believe cause the tubes to leak.

I would like to hear from Power
readers who are operating the same kind
of boiler if they too, have trouble with
leaking tubes.

C. F. Reimers.

Vienna, S. D.

desired pressure is registered.

If desired to test higher than 300 pounds
pressure per square inch. I would ad-
vise using a 3-inch cylinder, a larger
handwheel or a finer screw.

F. G. Chambers.

Syracuse, N. Y.

July 18. 1911

POWER

105

Babcock iN: Wilcox Headers,
Tubes and Baffle Walls

I would like to have the opinion of
some Power readers who have had ex-
perience with Babcock & Wilcox boilers,
on the following questions:

What are the various causes of cast-
iron headers cracking, and which style
of baffles, vertical or horizontal, causes
more header trouble?

With horizontal baffles, does the ex-
pansion of the lower tubes tend to push
outward on the headers and break them?

Do tubes which spring or bow. create
an inward pull on the headers sufficient
to crack them?

Should tubes be slightly flared at the
ends in the headers or not?

R. E. Pair.man.

Philadelphia, Penn.

"Make Good"

At this time when the central station
is figuring so largely in the life of the
engineer it behooves him to make him-
self something more than a mere engine
runner. He must learn his piece and be
able to recite it to the boss just as force-
fully as the central-station solicitor, and
be so equipped as to carry his point with
facts from his own engine room.

This is a condition that the engineer
can hope to attain only from the knowl-
edge of the or"-"ting conditions of his
own plant and by a continual effort to
better those conditions. Some hard work
is necessary but that is better than losing
his position.

A frequent inspection of the boilers
both inside and out will in most cases
repay the trouble and save considerable
on the coal pile, instead of going by
the fireman's report that everything is
all right. Feed-xater h.-aters scale up
and need cleaning as well as boilers, and
sludge should be kept out cf surge tanks,
especially where the suction is on the
bottom, as it will make a pump packing
last a good deal longer. Make your
traps work right and stop your leaky
valves; fill up the cracks in the boiler
setting and do not *ait for the combus-
tion chamber to fill up before you clean
it out. Then begi.n to regulate the firing
and feeding. Your mc'hod may not be
the one your fireman is used to and you
may have considerable tro'ible in get-
ting him broken in, but in most cases he
will cooperate as it makes his work
easier.

There is another side to the engineer's
conditions and possibilities which will
raise him in the eyes of his employer
from a common employee to an essential
factor in the successful opcrstion of the
business; he must be able to meet the
competition imposed upon him or he will
always be haunted by the central-station
fthost.
The man who carcfull> reads his en-

gineering journals, belongs to some en-
gineers' association and benefits by the
experience of his brother engineers is
the one who usually opeiates his plant
to the satisfaction of his employers and
without fear of central-station competi-
tion.

By combining the actual experience
gained in the engine room with some
technical training school or home study,
he is in a better position to judge
the merits of the new equipment placed
on the market, by the use of which he
may add greatly to the efficiency of his
plant. To be able to lay out plans for
changes or additions to his plant without
calling in the consulting engineer will
also do much toward winning the esteem
of his employer. To try to elevate en-
gineering to the rank of a profession I
consider the duty of every operating en-
gineer.

Tho.v.a.^ H. Watson.

Chicago, III.

Wavy Expan,sion Line

The accompanying diagram was taken
from a 2(Tx-!S-inch Corliss engine; speed,
90 revolutions per minute; steam pres-
sure, 125 pounds.

The diagrams show a very wavy ex-
pansion line. It is not due to a tight
piston or vibrating cord, as I have had
six different indicators and all produce
the same wavy line. This trouble did
not show six months ago, but is gradual-
ly getting worse.

Wavy Expansion Lines

I attribute the wavy line to wet steam,
but why should the steam change when
no changes have been made in the pip-
ing or in the boiler?

I would like to hear from someone who
has liandled wet steam and learn how he
overcame the trouble.

J. W. Dickson.

Memphis. Tcnn.

Twenty-odd years ago, Frank M. Clark
and I made an indicator in which the
diagram was traced by a spot of light
upon a white screen in a darkened room.
The movement of the spot was so rapid
that the entire diagram stood out brightly,
as when one makes an apparently con-
tinuous circle in the air by waving a
stick with a glowing spark at its end.
The diagram was drawn upon a large
scale, some four feet in length, and,
the beam of light which served as a
pencil lever having no inertia and the
stiff steel diaphragm which operated It

very little, the lines were ordinarily as
smooth as those of a waterfall.

The diagram from the little Armington
& Sims engine, which ran the shop
where we made the indicator, showed,
however, a compression line full of fine
ripples. We often had 'the indicator
upon that engine and the wavy line
always appeared. We conceived all
sorts of theories regarding the vibratory
action of steam to account for it, and
were still floundering in a tangle of nodes,
synchronic interference, sound velocity,
etc., when I happened, as we sat watch-
ing the diagram one evening, to open
the drip valve. The compression curve
flattened out some, of course, but be-
came smooth. We ground in the drip
valve and the compression line remained
smooth when it was shut; but by just
cracking it and adjusting if back and
forth carefully the wavy line could be
reproduced. A leak had been there which
produced vibrations in some such way
as a hole in a fire or the water faucet
which makes a deep, organlike rumble
when it is adjusted just so. This leak
seemed to have no effect upon the other
lines of the diagram but a larger leak,
such as might occur past a piston, pos-
sibly produces the waves which are puz-
zling Mr. Dickson.

F. R. Low.

New York City.

Plui^f^ed Boiler Nozzle

A new plant was being erected and
one of the 4-inch safety valves would not
operate. I suggested opening the bypass
on the throttle and also on the drips, and
drop the pressure on the boiler and then
take off the valve, as I suspected that
the wooden stopper which is sometimes
used in blocking the outlets on boilers
during shipment had not been removed
before putting on the safety valve.

Sure enough, the next day the engineer
showed me the wooden block which had
been nicely fitted to the nozzle opening.
D. L. Facnan.

New York City.

Sheet Lead Prevented Bear-
ings from Heating

Some time ago one of the journals of
a heavy locomotive gave considerable
trouble by continually running hot. It
was assumed that the trouble was caused
by an overhard brass bearing in the box.
The box was therefore raised off the
journal about ' i inch, and a piece of thin
sheet lead was inserted between the shaft
and the bearing surface of the brass
bearing. The lead was thus worked into
the pores of the brass and no further
trouble was experienced.

This plan was tried in several other
instances and proved successful.

F. W. Bentley. Jr.

Huron, S. D.

106

POWER

July 18, 1911

The Need of License Laws

I note in the issue of June 20 the
editorial and H. Taylor's article com-
menting on the need of license laws
covering the engineering profession.

The writer is a firm believer in such
laws as a protection to life and prop-
erty as well as a means of advancement
for the engineer.

Believing that the most direct method
of obtaining universal and uniform
license laws is by constant agitation on
the part of the engineering fraternity, I
wish to relate some incidents which came
to my notice in a northern New England
State where no such laws exist.

I was employed for a short time in a
portable sawmill a few years ago be-
fore I went to Massachusetts to work
my way up as a steam engineer.

This plant was not unlike all portable
mills, many of which still exist in some
parts of the country, and consisted of a
locomotive-type boiler with a slide-valve
engine mounted on top with its 6-foot
twin flywheels overhanging on either side.

The cylinder, about 10x15 inches, was
fastened rigidly to the front course of
the shell and the steam chest was con-
nected to the steam dome by an angle
throttle valve.

The main bearings were supported by
a cast-iron "saddle" riveted to the rear
course of the shell, a portion of which
had been cut away to allow the crank-
pin portion of the saddle to project into
the steam space of the boiler.

When in operation a crack would open
up under this saddle at every stroke of
the engine, first on one edge and then
on the other, according to whether the
steam was being admitted to the crank
or the head end ; steam issued from
these cracks in generous volumes.

At one time a crack developed in the
firebox sheet of the water leg that put out
the fire, and the boiler was laid off until
patched.

Steam pressure varied from 80 to 100
pounds on a gage that had seen hard
usage for a number of years; I do not
think it had ever been tested.

On a later visit my attention was
called to a leak in a small power boiler
which was a combination of locomotive
and return flue similar to a Scotch boiler
except that it was rectangular instead of
circular in cross-section.
I As near as I could ascertain, the crown
sheet was supported by hollow staybolts
from the-shell; one of these had evident-
ly become broken- as a jet of steam was

issuing from the center of it; the engi-
neer was at a loss to know what caused
the leak.

These instances are typical of condi-
tions which exist in some States where
anyone who can open a throttle is al-
lowed to have charge of high-pressure
boilers.

C. B. Hudson.

Lowell, iVlass.

Hot Bearings

I read with interest an article in the
May 30 issue on using sulphur in hot
bearings. Sulphur should not be used
in any very hot bearing as a great
amount of damage may be done in scor-
ing and cutting the brasses. In my ex-
perience when a bearing reaches the con-
dition where no ordinary oil can cool it,
the engine should be slowed down at
once and the bearing cooled by a stream
of cold, clean water to a normal tempera-
ture, after which a mixture of castor oil
and flake graphite should be made up.
Then take away the water and apply this
mixture freely; if graphite cannot be had
use a powdered sulphur along with the
castor oil, but do not use too much, not
as much as you would of graphite.

1 have cooled down a bearing 30 inches
long by 15 inches in diameter in this
manner in 25 minutes and run on again
for some considerable time.

Some complaint may be made by your
superiors for having stopped the machin-
ery for 25 minutes, but from experience
we found it wiser to do so than to run
the risk of a seized bearing which meant
a considerably longer delay. This hap-
pened once with me, and someone was
near getting, as you Americans term it,
"fired."

Having no forced lubrication, we use
the ordinary sight- feed drop lubricators;
with constant attention I think our fig-
ures compare favorably in consumption
of oil. It is always wise after a bearing
has been excessively heated to lift the
shaft, take out the brasses and scrape
the hard bearings caused by the heating.

and after starting up again apply the
same method.

Hot bearings occur at intervals, but
someone is to blame and the cause is
not hard to find by any intelligent man.
Caution your engine man as to what will
happen on a second occurrence. Do not
stint him in oils; I am sure he will make
every effort to prevent a recurrence.
Be sure you procure the best castor oil;
it will pay in the end.

H. G. Beard.

Mossend, Scotland.

Central Station Failure

Mr. Wise's article in the June 20
issue, "Central-station Failure," does not
seem to be founded on facts but more
on first newspaper reports of the acci-
dent at Philadelphia. If it were true that
service was interrupted for several days
and such a great loss as S250,000 was
emailed on the consumers it would then
be well indeed to give at least a pass-
ing thought to the proposition of install-
ing so called isolated -^'ar.ts.

To get down to hard facts and leave
out all guesswork, at 5:30 a.m., Satur-
day, May 6, a fire broke out in the sta-
tion which resulted in the shutting down
of one of the main distributing stations,
thus depriving consumers in a portion
of the' large area covered by the com-
pany in question for a number of hours,
not days.

Long before the fire had been entirely
extinguished the work of clearing away
the mass of twisted cables and feeders
was under way and all possible speed
being made to resume the service. The
mere fact of one of the main generating
stations being temporarily out of com-
mission was no handicap, for the others
had plenty of reserve engines and gen-
erators to more than make up the loss
and at the same time reach the affected
district through the large network of
interconnecting cables from other sta-
tions.

By ten o'clock, just 4'j hours after
the fire was first discovered, 30 per cent,
of the affected district was connected
and before noon 50 per cent, was con-
nected. By evening all but a small per-
centage of the consumers were receiv-
ing service apjiroximatina; the normal,
while all the theaters and other public
places were able to conduct their busi-
ness as usu.il.

As to the loss sustained by merchants,
etc., take the word of one of the largest
department ftore? as a sample of their

July 18, 1911

feeling of good will in the matter. Al-
though entirely dependent on this service
for power the Ir'ss sustained through the
interruption cf elevator service, liglning
and minor items was so small compared
with the usual amount of sales as to be
almost negligible. This is the first time
out of over 22 years of continuous ser-
vice that thcr; has been an interruption
of this kind.

Morgan G. Johns.
Philadelphii, Penn.

Burning Fuel Oil

In reference to W. A. Hamlin's article
on "Burning Fuel Oil" in the May 23 is-
sue, I think he is doing very well under
the present arrangements. He does not
give the cost of th- oil, but on a basis
of B.t.u. he is saving about 22 per cent.
by the change.

Assuming that the heating value of his
slack coal was 11.000 B.t.u. per pound,
or 44,000,000 B.t.u. for the two tons, and
allowing 18,200 B.t.u. per pound of oil
and 7'.. pounds per gallon for the 252
gallons, we have 34,398,000 B.t.u. to do
the same work formerly requiring 44,-
000,000 B.t.u., which represents a sav-
ing of about 22 per cent.

Authorities on oil burning all agree
that it increases the efficiency of the
oil to heat it just prior to firing, and de-
liver it to the burner under a pressure of
from 5 to 10 pounds per square inch, but
I doubt if he could do much better by
changing his apparatus.

Fred Wagner.

Chicago. 111.

Gathering Them In

The editorial in Power for June 13,
"Gatheriiii; Them In," suggests many
pertinent questions. As an engineer of
25 years' experience I ask the 21 to 29
engineers, how long they have been em-
ployed and in what capacity? Do they
read any trade paper or talk with other
engineers? Do they do the firing, or
teach the other man to fire, or let things
fun themselves? If the management has
a steam installation, why not make it
profitable ?
; Is the engineer in charge allowed to
I spend a dollar of the company's money
I for improvemcn:s? Are bis requests
I treated as worthy of notice? If he is
I not the right man let the management
[ get another; engineers are not all alike.
It may oe necessary to pay more, but the
' new m.in will have saved enough fuel to
I more than pay the difference.

Is the matter of power economy dis-
cussed with the engineer, and do the coal
I bills show that he is the right man in
i the right place? I have in my log book
I figures vhich are borne out by the office
I report of an isolated plant of approxi-
mately 2000 horsepower where in corre-
sponding months of 1909 on steam drive

POWER

and of IPIO on central-station electric
drive about ?800 was saved by steam
drive. The treasurer reported having
saved SI 000 by steam drive. The com-
pany expected to get very cheap power
with the electric drive and hoped that
by the terms of the contract the sav-
ing would pay for the equipment.

After' the first few months I never
heard anything more about cheap power
or of delays in transmission lines. If
some of the manufacturers in that "pros-
perous Massachusetts manufacturing
town" want these figures they can get
them through Power.

Alonzo Thorndyke.

Argylc. \'t.

A Boiler Explosion Averted

Edward T. Binns has a letter in the
June 20 issue under the above caption.
Now, I do not say that the boiler setting
he describes therein is the best that can
be devised, but the ones here at my
plant are set that way and I cannot see
that they have suffered any bad effects.
The boilers have been in for about four
years and the insoector says that they
are in first-class condition. There are
also two lap-ssam boilers standing out
in the yard which have had about 20
years of service in settings of this same
kind. They would still be good for duty
under a moderate steam pressure.

It is my opinion that those rivets were
sheared by some "leatherhead" building
a rousing big fire when first starting up.
J. Hilton.

Winfield, Kan.

I was much interested in Mr. Binns'
letter in the June 20 issue under the
above heading.

I have been in charge of two boilers
for the past three years that are set
as Mr. Binns described, the hot gases
passing over the top of the shell, the
object being to superheat the steam. Al-
though these boilers have never shown
any signs of defect, ' have never felt
as well satisfied with them as if the top
of the boilers were protected from the
gases. These boilers have been inspected
by several inspectors and I asked each
one for his opinion. They all told me
that they did not like that way of setting
a boiler but that they did not think there
was any danger.

William Swope.

Tiffin, O:

Writing for the Magazines

For some time past there have appeared
in Power and other mechanical papers
numerous articles on how to write for
the trade press and why more engineers
do not write for publication.

Many feel that their lack of the ele-
mentary branches of the English lan-
guage, their weakness in spelling, the
manner of expressing themselves on

107

paper, and perhaps their meager knowl-
edge of mathematics, will disqualify them.
While these failings are drawbacks,
they should not bar the way for one who
really has something to say that will
benefit enough of the readers to warrant
its publication.

It has been the good fortune of the
writer to travel, particularly in the East-
ern and Central States, and he has been
brought into contact with men in all
branches of the engineering profession
from the lowest to the highest, from the
ten-dollar-a-week engineer-fireman to
men who are in charge of the largest and
best plants in the country. Tliese men
are often asked, "Do you ever write for
puDlication?" and the great variety of
answers would make a very interesting
volume.

Here is one reply from a middle-aged
man in a plant of perhaps 300 horse-
power. He said: "I once wrote an article
for a magazine and in about two weeks
it was returned with a typewritten letter
telling me that as they had so many con-
tributions on hand on the same sub-
jects they were forced to return a num-
ber of them. That discouraged me right
then and there. I wrote to them on the
back of their letter to stop my subscrip-
tion and keep the change, and I have
not taken an engineers' magazine since."
This man was easily discouraged.

Another man said: "Yes, I wrote a let-
ter once to a trade journal and in a
month or two I got a check for about S5
for my contribution; they said it ap-
peared in a recent number. I hunted
through it and finally found my initials
at the end of an article that was no
more like my copy than day is like night.
Those editors slashed it all up, seasoned
it with some big words, high-fiown ex-
pressions and advanced theories, and
then sent me the money to pay me to
notice the difference. That interested
me and I began to learn to spell. My
wife taught me evenings. Then I studied
grammar from the same teacher. In
about a year I wrote again and compared
the results, and really found whole
sentences just as I wrote them Then I
learned to draw at night school and now
when I send in a contribution I can il-
lustrate it as well."

These two answers will illustrate the
variety of replies to my question as to
why men never write for the press. The
principal requirement is thai the pro-
posed article is meritorious enough to
warrant publication. If so, write your
rtnry. Do not put in a superfluous word.
/Make it concise and yet convey the full
meaning intended. After writing it, look
it over carefully, correcting the spelling,
punctuation, etc. Then rcwritj it if it
is not neat and legible. Perhaps your
employer will permit his stenographer to
prcpar? a typewritten copy for you. Em-
ployers appreciate this display of knowl-
edge; they have a high opin'on of an

intelligent, ambitious employee, and they
receive the benefit of their engineer's
studious habits.

While the money which you receive
for your contribution is an addition to
your salary, do not write for that alone;
if you feel that you have got something
to say that will benefit some brother en-
gineer, write it and send it to the editors.
Leave it to them to determine the amount
you will receive for it; they will treat
you squarely.

The writer has been benefited many
times by the printed experience of a
brother engineer and can safely say that
there is not a contribution published in
any engineers' magazine but that has
benefited a number of readers to an equal
extent.

Then there is another class of men
v.'ho ought to write and do not. They are
the engineers who are the leaders of the
profession, the men who have passed
through the elementary grades and have
taken a post-graduate course in that
great institution, the School of Experi-
ence.

Think up your experiences and ask
yourself if they will help anybody else.
Then get busy.

G. H. Wallace.

Racine, Wis.

Belting vs. Electric Trans-
mission

In the June 20 issue, there is an answer
to my letter in the issue of May 2, by
Franklin Van Winkle.

I am sorry that I made the statement
about his taking exception to my article
in the February 14 issue. I so worded
my letter that it would bring a reply, and
I always aim to write not only to give
such information as I can, but also, if
possible, to bring forth arguments for or
against such subjects as may instruct
me as well as assist others.

The matter of economy in electric
drive is very largely the economies to be
gained through flexibility of the appa-
ratus. A well laid out mill plant should
be and frequently is at the start more
economical than a plant electrically
driven, but if, because of the conditions
of installation in many plants, the drives
arc not well laid out, the resulting op-
eration is by no means satisfactory. Most
every factory is built with the idea of
future expansion, as no mill owner pur-
poses to stand still; he always hopes
that his business will increase and that
the mill will expand. Few owners, how-
ever, have sufficient cash or nerve to
install shafting and belting with the idea
of its being capable of carrying the uUi-
mate expansion that they expect; first,
because of the very heavy additional
overhead charge which would exist dur-
ing the time when the mill was small,
and, second, because few of them are

POWER

able to figure in just what direction ex-
pansion will take place. The result is
that when expansion does take place, the
machinery is added and the original belts
and shafting have to carry the additional
load until the slip and friction and belt
wear and belt breakage become very im-
portant factors. Slip to a large extent
can be overcome by changing the ar-
rangement of the pulleys; but it should
be remembered that there frequently are
conditions in factory operation which re-
sult in light loads upon the plant, and if
the belts and pulleys are so proportioned
that the belt speed is proper when the
factory is running under full load and the
machinery under these conditions is run-
ning to its maximum productive capacity
or safe speed, the machinery will under
conditions of light load run at a con-
siderably higher speed and may result
in breakage or produce an inferior
quality of output.

It is far easier to install a new line
of shafting where electric drives are
used than where belt drives are em-
ployed. A new line under these condi-
tions simply means placing the shaft
where it may be desired, without refer-
ence to other shafts, and driving direct
by a motor, the wiring of which is very
simple. If belt drives are used, the shaft
must be located with reference to other
shafts; and if the load on the new shaft
be heavy, it means an entire rearrange-
ment of the belting from this shaft to
the main drive or overloading the belts
already installed; frequently the arrange-
ment of the shafting is such that it will
not allow the best arrangement of the
machinery. It is fortunate that the pro-
portion of plants where bad belt drives
are installed is not large. If it were,
the engineering fraternity and the mill-
supply dealers would be driven far be-
yond their capacity. While the propor-
tion is small, the total number is large,
and there is plenty of room for improve-
ment in the manufacturing world along
power-transmission lines. It is not al-
ways the question of power economy
which brings forward electric motors;
it is largely a question of economy of
space and economy of operation as well
as flexibility in its adaptation. A new-
plant may be installed with power ap-
paratus sufficient for its needs; shafting
may be adapted for the machinery at
first installed and the original layout
kept consistently small. Any further ad-
ditions to the plant are temporarily taken
care of by the overload capacity of the
generator; if this is exceeded, a new
generator is installed to operate in paral-
lel with the existing one and the plant
is operated economically and allows at
the same time for both shafting and ma-
chinery to be installed and operated in
its most economical location. It is un-
fortunately true, as Mr. Van Winkle
states, that the American manufacturers
pride theiuselves on their alertness in

July 18, 1911

adopting improvements inductive to econ-
omy, but they do not always follow
along the lines on which they operate
themselves. They are far more apt to
consider that they know what is and
what is not economical, not considering
that anyone can tell them anything about
their business. While it may be per-
fectly true concerning their main busi-
ness, it is also a fact that there are lots
of people who can assist them in certain
parts of their business. These manu-
facturers are willing to pay a very large
sum to a buyer who purchases the raw
material for their manufacturing busi-
ness, paying him a large salar>' for his
knowledge along these matters; but these
same people object very strenuously to
paying a fair price to a man for his
knowledge along power-transmission in-
stallation and operation; they depend al-
most entirely upon their engineer or
master mechanic who has probably been
brought up in the plant and has been
given little or no opportunity to go out-
side to enlarge his knowledge. It is no
reflection upon either the engineer or the
master mechanic to say that there are
people who could go over the plant and
ver\' shortly find places where marked
improvement could be made; there are
many very excellent men handling plants
and installing new machinery in the old-
fashioned way simply because that is the
way they have always done it.

Still another reason why changes are
not made in many power plants is be-
cause the power item is as a rule a very
small proportion of the total cost in a
manufacturing establishment, so small
that the saving of half the power would
represent but a small percentage in the
total yearly cost of operation; and many
manufacturers so look at it in this light
that they lose sight of what it actually
might mean in dollars and cents.

Henry D. Jackson.

Boston, Mass.

Friction Load Diagrams

The diagrams taken from an Ames en-
gine and submitted by Mr. Smallwood
in the June 20 issue are similar to some
that I have seen before. Under light
load the engine might be considered as
single-acting and working against a steam
cushion. If Mr. Smallwood will scrape
in the valve and see that the piston is
tight for its full travel, I think a different
diagram will be produced.

There is a loop in the head-end dia-
gram as well as in the crank-end. the
loop in the latter coming much further
down. By getting the valve tight this
loop will shorten up.

C. R. McGahey.

Baltimore, Md.

It is not altogether what is in the coal i
but what can be got o'ut of it that makes j
it valuable. I

July 18. 1911

P O >X' E R

109

Issued Weekly by the

Hill Publishing Company

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Contents

An Interesting I.solated Power Plant 84

Renaissance of the Naral Reciprocating

ICngine 87

Equal Work In Compound Knglne 88

Recent Oerelopments In Testing Boiler

Tubes ni

Combined Coal and Ash Conveyer 92

Recent Work of U. S. Bureau of Mines !>.'{
Correcting Low Power Factor with

Synchronou.s Motors '.H\

The Maintenance of Klcctrlc Circuits.... !I7

Adjusting a Belted Kxclter !IS

Wali-r Tank Signal System !18

The Effect of Varying the Supply of

Steam to a Gas Producer Jin

Practical Letters :

Pins In Loose Crank Pins. . . .Make-
»hlft Valve Repair .... Successful
Isolated Plant .... Trouble with
I.eaklng Tul«-». . . . Pipe and Kitting
Tester Balicock & Wilcox Head-
ers. Tubes and Ballle Walls....
"Make Goo<I" .... Wavy Expansion
Line. . . . Plugged Boiler Nozzle. . . .
Sheet Lend Prevented Bearings from

"eating 10.3-105

DlMMIRitlr.n I.elters:

The Need 6f License l.aws. . . . Hot

Bearings Central SInllon Failure

...Burning Fuel Oil. .. .Gathering

Them In A Boiler Explosion

Averted Writing for the Magn-

«lnes Belt vs. Electric Trans-
mission .... Friction Load IHa-

grams lon-loH

EdllorlBls loni 10

Hot Water Heating Iiy Forced Clrcnlntlon 112
Chlrsgo Meeting of the Henllng and

Venlllntlng Engineers jl.';

Ventilation of the Macy Store, .New

York ) 1 ,•;

Improving CIrmlallon through Healing

•^■''"» Ilfl

Radlntorn Give Trouble 117

AvnIlBlile Hent In Stenm Boilers... im

Heat Availible to Steam Boilers

— Effect of Moisture in

the Air

In a recent issue of Engineering, T. B.
Morley, B. Sc, of Glasgow University,
criticizes the usual treatment of the
moisture in the coal in making up the
heat balance and computing the efficiency
of a boiler.

The boiler is charged with the number
of heat units in the dry fuel, but if it
has to use a considerable proportion of
these to evaporate and superheat to the
uptake temperature the moisture in the
coal its efficiency, computed as the ratio
of the heat units in the steam made in-
side the boiler to the total number of
heat units furnished, will be less than it
would were that efficiency computed up-
on the heat units available for steam
making after the fuel had evaporated
its own moisture.

So far the criticism appears to be war-
ranted. A boiler is not to blame if it is
furnished with wet coal; and it is not
enough to reduce the charge to the weight
of dry coal and leave the moisture for the
boiler to get rid of without credit.

But when he attempts to apply the
same reasoning to the moisture in the
air with which the furnace is supplied,
Mr. Morley seems to have fallen into
error. Near the end of his article, which
is reproduced upon page 1 18, he says
that in certain boiler experiments recent-
ly reported "the moisture carried into
the furnace in the air supply amounted
to no less than 0.34 of a pound per
pound of dry coal; the heat required to
convert it into the condition in which it
reached the chimney would be about 3.4
per cent, of the heat of the dried fuel."

The moisture in the air might amount
to 0.34 of a pound per pound of dry
coal. Air at eighty degrees Fahrenheit
can carry over two per cent, by weight
of moisture, and with quite practicable
degrees of humidity and amounts of ex-
cess air might carry the quantity in ques-
tion. But this moisture in the air is In
the form of water vapor — steam.

It is already evaporated and will ab-
sorb only the heat necessary to raise it
from a state of dry saturation at the in-
take temperature to the superheated con-
dition in which it leaves the furnace.

A pound of dry saturated steam at
eighty degrees carries 1094.8 heat units;
a pound of steam at fifteen pounds ab-
solute pressure superheated five hundred

degrees carries 1385.5 heat units, accord-
ing to the Marks- Davis tables. Each
pound of moisture in the air supplied
by combustion would therefore, if it en-
tered at eighty degrees and left at five
hundred and eighty degrees, absorb 290.7
B.t.u., and 0.34 of a pound would absorb
only about one hundred B.Lu., which is
by no means 3.4 per cent, of the heat in
the dried fuel. This would be some four
hundred or five hundred B.t.u., enough
to evaporate 0.34 of a pound of water
from eighty and superheat it five hundred
degrees. Is it possible that Professor
Morley overlooked the fact that the mois-
ture in the air differs from that in the
coal as the atmospheric moisture is al-
ready vapor and does not need to be
evaporated while that in the coal is a
liquid?

Effects of Varying the Rate of

Steam Supply to a Gas

Producer

In the Gas Power Department of this
issue will be found a comprehensive ab-
stract of a paper recently read before
the British Institution of Mechanical En-
gineers in which the author describes
the results of a series of tests made to
determine the effect of varying the ratio
of steam to air, or more accurately,
steam to coal in a power gas producer.
The report is well worth careful and
analytical study, notwithstanding the
fact that the outfit was too small to
justify one in considering the results of
the tests as general criteria. The gen-
erator was so small, for example, that
increasing the steam supply did not pro-
duce anything like the increase in car-
bon dioxide which everyday practice
shows. The author, too, is a little dog-
matic in some of his deductions; for ex-
ample: "This result shows that the
maximum amount of steam that can be
decomposed by anthracite at 1832 de-
grees Fahrenheit is about 0.535 pound
per pound of coal." Such a hard-and-
fast conclusion based on tests with a
generator ten inches in diameter by
twenty-five deep is unsafe, especially In
view of the fact that the vaporizer was
inadequate to evaporate all of the feed
water.

One of the most Interesting results
of the tests was that the maximum pro-
portion of combustibles was obtained in
the gas when the rate of steam decom-

110

position was about fifty-two per cent.
of the rate of coal gasification, but it
would have added much to the value
of the tests if the investigator had gone
into the effect of varying the rate of air
supply also. If memory serves reliably,
forty per cent, of steam is about as high
as American anthracite will take for best
results, the rate of air supply being also
appropriate. Mr. Allcut lays stress on
the fact that the best conditions existed
when the water feed rate was about
seventy-two per cent, of the coal rate,
but as only some seventy-two per cent,
of the steam was then decomposed, the
steam to coal ratio was really about
fifty-two per cent., as already stated.

However, the results obtained by Mr.
Allcut are of a great deal of value, when
proper allowances are made for the dis-
turbing effects of the small size of the
generator employed. We should like very
much to see such a painstaking series
of tests carried out in this country on a
producer of, say, two or three hundred
horsepower.

As this editorial is being written, we
find that the tabulated results of Mr.
Allcut's tests were accidentally omitted.
This table will be printed next week.

Safety Stops

The safety cams on a Corliss engine
valve gear are put on to prevent an ac-
cident due to the engine taking steam- at
full stroke, should the governor from
any cause descend to its lowest position,
just as a safety valve is placed on a
steam boiler to prevent an accident if
the steam pressure should tend to rise
above a safe point.

There is one radical difference, how-
ever, between these two safety devices:
while the safety valve may be set for
the desired pressure and not be tampered
with further, except to see that it is free
to operate, it is necessary to block the
governor in an unsafe position every
time the engine is shut down, so that it
may be started again.

Engine builders have provided stops
of various kinds for this purpose, many
styles requiring that the engineer place
them in the safety position after the
engine has attained sufficient speed to
raise the weight of the governor from
the stop. There is no excuse for using
a stop of this character as there are
numerous simple means by which this
action may be made automatic; many of
them have been described in our columns
from time to time.

.■\n engineer is very negligent if he
continues to operate an engine with a
stop that is not automatic; and he is
criminally negligent if, as is often the
case, he so purposely changes an auto-
matic device of this character that it is
rendered inoperative. Should an acci-
den» occur under such conditions due
to the misplacement of the stop he should
be treated the same as any other criminal.

POWER

Why should a nonautomatic stop on a
steam engine be tolerated any more than
a stop valve between a boiler and its
safety valve? Flywheel explosions are
of alarming frequency, and the records
of a company doing both flywheel and
boiler insurance tend to show that the
hazard connected with flywheel insurance
is far greater than in boiler insurance,
a flywheel apparently being 30 per cent,
more liable to explode than a boiler. The
point to be first considered in power-
plant operation is safety, and it behooves
the intelligent engineer to remove without
delay such a simple cause of flywheel
accidents as a nonautomatic safety stop.

The Importance of Brains

Some men are prone to be so dully
perceptive of the exceeding earnestness
of life, of the right uses of their mental
faculties, that it is quite possible the
forceful if som.ewhat vulgar expression,
"He's a dead one," had its origin in this
observation. Carlyle wrote some seventy
years ago, "It is a most earnest thing
to be alive in this world."

Mental development plus energetic
labor makes for commercial and industrial
success and keeps the wheels revolving.
An observant man on entering a big
power plant of the present day is pro-
foundly impressed with the evidences of
mechanical genius that are to be seen
everywhere about him; the plant fairly
bristles with brain products.

With the necessity for machines of
immense capacity has come the demand
for the highly skilled workman, the me-
chanic who works with his brains. The
plant owner w-ho told the maker that
he wanted "machines so simple that any
fool could operate them" failed to realize
that this particular fool and his machine
are soon parted, to paraphrase the old
saying.

The enormous sums of money annual-
ly invested in power plants in the United
States alone would yield little if any
return were the owners not keen to the
necessity for employing skilled labor.

So large is the skepticism of a few in-
dividuals that under ordinary conditions
they only believe in those things which
they see with their own eyes. As they
have never seen their brains we may be
pardoned for appropriating their own line
of argument: Their brains have no ex-
istence in fact. It is this type of man
who "ain't got no use for book learnin'
and them theory fellers," and they make
about as big a showing among their fel-
lows as does a pimple on a fat man's
nose.

The bright, common-sense mechanic
is rapidly beginning to know that to de-
velop a thorough working knowledge of
his vocation, the theory as well as the
practice is required if he expects to go
to the top. He sees the importance of
brains and will set them to work at once;
that it is not sufficient to know what is

July 18, 1911

good practice but why — and the why is
the theory.

To be sure, theory must be kept within
bounds; theory and "theorizin'," as Mul-
vaney called it, are widely apart. Occa-
sionally an enthusiastic young college
graduate may think that he can instruct
the best operating engineer who ever
ran an engine and detect faulty design
in an almost perfect machine. Of course,
he is "all down but nine," as the bowlers
phrase it. But when this young hopeful
has overcome his reluctance to the over-
alls and the shop — has come within
bounds — his brains tell him he is but
poorly equipped as an engineer until
his apprenticeship has been served under
the eye of the skilled, intelligent me-
chanic and he has acquired the highly
necessary practice.

Government Research Work

While the newspapers have been print-
ing glaring headlines on "conservation"
and certain individuals have been stump-
ing the country preaching "efficiency,"
the Government has been quietly con-
ducting scientific investigations which are
destined to have a far more permanent
effect upon engineering economy.

This refers to the experimental work
upon fuel, combustion, feed water, etc.,
which was formerly carried out under
the supervision of the Geological Sur-
vey but has now been transferred to a
separate department, the Bureau of
Mines. Under the direction of this bureau
the scope of the work has been extended
and excellent results have been attained,
as will be noted from the report to be
found elsewhere in this issue.

The majority of small plants and in-
dustrial establishments have neither the
money nor the facilities for conducting
research work, and many of the larger
plants that have consider the results as
"company data." Moreover, commercial
tests, however accurate, are always
looked upon as more or less biased; con-
sequently their value as general engi-
neering information is often unjustly
discounted.

The work of the Bureau of Mines,
however, is known to be strictly im-
partial; it is carried on by a corps of
trained experts and the results are at
the disposal of those sufficiently in-
terested to send for the bulletins. For
these reasons this department of the
Government should receive the hearty
support of all those engaged in power-
plant engineering.

Engineers are finding out that the air
space in the brick setting of boilers is
not such a help in preventing heat radia-
tion as has been generally believed for
years past

Engineers who possess the most in-
formation seldom use it in belittling the
n:&n less fortunate.

July 18, 1911

POWER

Object of Fine Gcis Analyses

What is the object of flue-gas analyses,
and what does the presence of carbon
monoxide ( CC' I in the flue gas indicate?
O. F. A.

Flue-gas analyses are made for the
purpose of determining the conditions of
combustion obtaining at the time the gas
is made. The CO indicates a lack of air.
If the combustion is perfect, all of the
carbon will be burned to CO:,, but if not
enough air is used, part of it burns to
CO and gives up only about one-third of
the heat that comes from burning it to

CO:.

Air in Pump Miction Pipe
We had a 4x2' .•x4-inch pump installed
to pump water from a couple of wells.
The first suction pipe was 1 inch and
the pump ran all right, but did not give
enough water. The 1-inch pipe was taken
out and replaced with a 1 '4-inch. The
pump would not then deliver as much
water as it did before. A 6x4x6-inch
duplex pump was then tried. It handled
the water but would not run faster than
a certain speed, owing to the friction in
the suction pipe. What is wrong?

S. C. A.
From the behavior of the small pump
It would seem that there are air leaks
in the suction pipe, which, though not
large enough to affect the larger pump
noticeably, still admit air enough to
seriously interfere with the operation of
the smaller one. You can, of course,
see that at the same rate of piston speed
the duplex pump will take care of about
five times as much water as the single
one. and consequently a correspondingly
lari^er volume of air.

7J<'.f /;'■///// !f Hiiiiiped He (id

How do you find the radius and the
thickness of a bumped head?

O. W.

The radius to which a head should
be bumped is determined by the formula

/• X /'

in which

/? = One-half the radius to which

the head is bumped;
F= Factor of safety;
P = Working pressure;
Sr^ Tensile strength of material;
7= Thickness of the head.
To find the thickness, transpose the
formula to

/? X /-" X P

Cohiips/ii<^ Strength of Cone

.\ cone-shaped flue has a greatest
diameter of 36 inches, a least diameter
of 12 inches and a length of 20 inches.
It is built of 5 16-inch steel plate of
a tensile strength of 60,000 pounds per
square inch. What collapsing pressure
will such a flue safely withstand?

W. P. C.

It is customar\' in short cones to take
the mean diameter, in this case

.^6 4- T2 . .

■ = 24 inches

and calculate the collapsing strength.
Hutton's rule is

/' X 1 L
where,

T — Thickness of plate in thirty-sec-
onds of an inch;

I2r- ■■».

Cone-shaped Flue

D = External diameter of shell in

inches;
L — Length of shell in inches;
C = 060 for mild-steel plates, and
P = Collapsing pressure.
Substituting,

.S

= T

24 X 1 io

The collapsing pressure must be
divided by the factor of safety and in
view of the high temperatures and wear
and tear this should be 6. The allow-
able pressure would then be 102..'^ pounds
per square inch. The cone must be
truly circular in form.

The bracing for the flue- should be
placed as shown in the accompanying
sketch in order to prevent the flue from
being pushed down by the pressure ex-
erted on its inclined surface.

Efigitie Steam and Exhaust
Pipes

How is the size of steam and exhaust
pipes for engines determined ?

S. E. P.

The steam pipes should be so pro-
portioned that the mean velocity will
not exceed 6000 to 8000 feet per minute,
and that in the exhaust pipe around 4000.
A considerable diversity of practice ex-
ists and it is largely a question of how
much drop in pressure one is willing
to stand.

Open and Closed Feed Water
Heaters

What are three advantages of an open
feed-water heater over one of the closed
type ?

O. C. H.

An open feed-water heater saves the
condensed steam which brings the heat
to it; it saves the heat which would
otherwise go out in the water of con-
densation and as usually arranged with
a settling chamber and filter it takes out
the impurities which are deposited at the
tetiferature to which the water is raised.

// 'ater Tube and Return Tubular
Boikrs

What are three advantages of water-
tube boilers over return-tubular?

W. R. T.

A water-tube boiler is not so liable
to disastrous explosion as a shell boiler.
It is adapted to the carrying of higher
pressures than externally fired shell boil-
ers can carr)' in any considerable sizes,
and it gets a larger capacity into the
same space.

Suet ion Chamber

What is the object of the chamber on
the suction line of a pump?

P. S. C.

The object of an air chamber on the
suction line of a pump is to take up
the impact of the moving column of
water and to give a more uniform flow
to the pump cylinder.

POWER

July 18, 1911

Hot Water Heating hy
Forced Circulation*

By Ira N. EvANst

It has always been conceded that hot-
water heating is the most economical
and satisfactorj' method because of the
flexibility of the medium in its wide
range of temperature to meet changes in
outside weather conditions.

It is understood that the circulation of
a gravity hot-water heating system is
induced by the boiler or heater warming
a column of water in one part of the
system whose lighter weight is balanced
against a column of colder water in an-
other part, causing a flow to regain its
equilibrium. The circulation is therefore
dependent on the hight of the apparatus
and a difference in temperature of the
circulated medium in different parts of
the system or there is no movement.

The low temperatures and slow cir-
culation of the gravity systems due to
the slight difference in weights of the
cold and jhot columns require mains
and radiators of sizes so large and so
expensive as to be prohibitive on a job
of any magnitude.

To overcome these objections forced
circulation was employed by introducing
into the hot-water circuit a mechanically
operated pump.

In proportion to the amount of power
applied to the pump to circulate the
water the temperature of the medium be-
comes independent of the power of cir-
culation. A reduction in the size of
mains occurs as well as an in-
creased efficiency in radiators, boilers and
heaters to transmit heat units from
steam, water or hot gases. Grades can
be disregarded and the only limit to the
distance is the first cost of the pipe lines
when compared with that of another
plant.

Where steam power was available for
power purposes hot-water boilers were
replaced by heaters to warm the cir-
culated water by either exhaust or live
steam from the power boilers.

The above described arrangement is
known as the system of hot-water heat-
ing by forced circulation and is appli-
cable to large central heating plants
where the distances transversed are long
and it is desirable to use waste heat
from any source.

Hot-water heating by forced circula-
tion has been on the market in various

•Copyrighted, 1011, by Ira X. Evans.
■fConsiilting engineer, heating and power.
New Yorl? (Tty.

forms for about 18 years, but the major-
ity of owners and engineers have but
slight conception of its possibilities as
there is a dearth of literature on the sub-
ject.

All systems of hot-water forced cir-
culation require a pump in the circuit
but differ in the forms of heaters and
their connections and methods of handling
the steam and condensation.

The inventor of the first system
stumbled on the idea during his practice
while engaged in heating a greenhouse
on a level considerably below that of
the boiler house where a gravity system
was •ut of the question. For many years
noncondensing engines only were used
to supply the exhaust steam to heat the
water, thus positively doing away with
back pressure by omitting the back-pres-
sure valve from the exhaust pipe. The
next step was the development of this
system in connection with turbine and
condensing engines.

The type of heating surface, whether
direct or indirect, is practically the same
as for steam systems, only instead of a
larger supply pipe and small return there
are two pipes of the same size de-
pendent on the quantity and velocity
of the water required to be circulated.

In the first installation the pumping
capacity was comparatively small in pro-
portion to the heating surface and this
is the error most engineers make in
their first installation. A few of the
special schemes of heating by this meth-
od are described, and all of them include
the continuous circulation of the same
water and heaters of the closed type with
no connection between the steam and
water spaces, the heat units being trans-
mitted through the tubes and surfaces.

One system has a hot-water heating
boiler in the circuit through which the
water is circulated which absorbs heat
from the fire under the boiler. A low-
pressure tubular heater may be included
to utilize the exhaust steam from the en-
gines. The boiler is operated when the
exhaust steam is insufficient. This re-
quires the installation of hot-water boil-

ers in addition to the steam-power boil-
ers in the same plant, which are idle in
summer.

It is very difficult to regulate the fire
under hot-water boilers on account of
the wide variation in heat requirements
due to outside wegther coi.ditions. More
boilers are needed in extremely cold
weather and when it suddenly moderates
the fires have to be banked. This makes
the plant difficult to control as regards
the temperature of the water.

Several town heating plants were in-
stalled in the West using the hot-water
forced-circulation system. Hot-water
boilers were installed to heat the cir-
culated water and in some cases the live
steam for heating was supplied to a
heater from power steam boilers. The
special feature of this system lay in
the method of utilizing and storing the
heat of the exhaust steam.

An exhaust heater was installed and
the exhaust steam from the engines was
condensed by storage water circulated to
a large tank in series with the heaters
and pumps. The use of a tank or reser-
voir of water of sufficient capacity to
store the heat at periods of heavy engine
load was necessary and was used dur-
ing periods of lighter load.

A piston-type pump circulated the
water which w-as forced to the highest
point of the system and allowed to flow
back by gravity through a small return
opening controlled by a valve. In this
manner the pump had to work against
the greatest static head of the system
as well as the friction head due to the
piping. This method also required an
excessive drop in water temperature. It
was also found that no isolated tank or
resen'oir of practical size would hold
sufficient water to allow an appreciable
amount of heat storage, thus causing
the abandonment of this feature. A
common arrangement is the use of one
large heater having an exhaust connec-
tion with a back-pressure valve and a
live-steam connection through a reduc-
ing valve, a pump and receiver handling
the condensation, the pump for the cir-
culation of water through the mains and
radiators remaining as usual.

This arrangement has flexibility and
the circulation is independent of the tem-
perature of the circulating medium, but
many features in the handling of the
condensation are lost by this method. The
pump and receiver reducing valve and
the back-pressure valve involve most of
the difficulties of the vacuum steam sys-
tem.

July lb :9n

POWER

113

Another arrangement advocated by a
large firm is the placing of the live-steam
heater and exhaust-steam heater in
parallel as regards the water connec-
tion, but this has the effect of reducing
the capacity of the heating surface in
the heaters if used together as only one-
half of the water in the system flows
through each heater. If this connection
were full size and the heaters were not
used at the same time, it would not make
an appreciable difference provided the
water connection to the heater not in
use were closed. The high-temperature
steam available in the live-steam heater
over the temperature of the exhaust in
the other makes the advantage of the
series connections apparent.

There is a system of town heating op-
erated in Ohio which utilizes a cooling
tower in connection with the heating sys-
tem to act as a condenser.

The exhaust heater and the surface
condenser are combined, the water pass-
ing through the condenser to the heating

is reduced below that of the boiler to
an extent greater than the column of
return water between the level of the
water in the heater and the water line
of the boilers, the operation is as fol-
lows: An injector tee / and separate 1-
inch steam line / from the boilers inject
the water back into the boilers and over-
come the difference in pressure between
the heater and boiler. This injector will
generally be required if there is less
than 10 feet between the water line of
the boilers and the bottom of the heater;
under conditions of extreme service it
should be shut off.

When only a portion of the heater
capacity is required the steam valve to
the heater is throttled to the point de-
sired and the condensation covers the
tubes, thus reducing the amount of ex-
posed heating surface automatically with-
out interfering with the equal expansion
of the tubes and the shell.

When the throttle valve on the heater
is wide open and a further capacity is

through a steam engine, notwithstanding
the superheating effect. For the above
reasons when live steam is handled di-
rect to the boiler by the injector method
there is a saving of about 10 to 15 per
cent, on the amount used and the diffi-
culties in the proper connection of a re-
turn trap are avoided.

The live-steam heater should have a
capacity sufficient to heat the water for
the entire plant under maximum condi-
tions without the exhaust heater. Its
size should be determined under a steam
pressure of about 100 pounds. The
power boilers may operate normally
under a higher pressure, but as the
heater is used in industrial plants when
the engines are inoperative it is ad-
vantageous and generally customary to
lower the boiler pressure to about 100
pounds at that period. This does not in-
crease the size of the heater materially
and gives greater capacity.

The exhaust heater is connected in
series by the water pipes with the pumps

:Air Trap

Separate Return

Hot-Well Fumps

Diagram of Connections of Hot-water Heating System

pystem and thence back to the cooling
lower. The vacuum corresponds closely
»o the temperature required for the heat-
ing water in the flow main. In this sys-
"em the pipes would be subject to
pitting on account of the new water in-
troduced to replace that lost by vapor
from the cooling tower, and necessitates
pumping against the total hight or static
head of the system unless the cooling
tower can be made the highest point
f>f the system.

The best practice is shown for water
I'nd steam connections for operating un-
aer condensing conditions in the accom-
panying Illustration. The live-steam
;ieatcr is placed over the boilers as high
i» conditions will permit to obtain a
5r«vity return for the all-live steara used
>n the system. The condensation re-
urns to the rear drum of the boiler
>y gravity at nearly the same pressure
ind temperaiurs as the wafer in the
twjilers.

I When the condensation of the steam
k»0 heavy that the pressure In the heater

desired, the injector tee is employed. The
fact that the bottom of the heater is full
of water at a less temperature and pres-
sure than the boiler makes the conditions
favorable for the action of the injector.
It should not be unnecessarily used;
warning is given by a slight snapping
in the return pipe which shows that it is
emptying.

When a pump and receiver are used
with a live-steam heater the latent
heat units in the exhaust of the pump
nearly equal or exceed those in the re-
turned water, and, as a rule, a vapor
pipe is provided on the receiver and a
drain trap is placed between the receiver
and the heater. Part of the discharge
froin the trap will reevaporatc because
the pressure is lowered and is lost
through the vapor pipe. The difficulties
with pumps handling high-tempcraturc
condensation are well known.

In practice there is nearly the same
loss and effect in passing steam through
a reducing valve due to wiredrawing
condensation, etc., as passing the steam

and live-steam heater with bypasses and
valves as shown.

When operating on a condensing plant
the connection between the engine or
turbine and the condenser arc made as
indicated; the amount of vacuum on the
heater regulates the water temperature
and is controlled by opening or closing
the valve X. There may be full vacuum
on the condenser with other units ex-
hausting into it. The dry-air pumps and
condenser circulating pumps are not
shown.

The hotwcll pumps handle the con-
densation from the condenser and heater
and are cross-connected. They discharge
to the open feed-water heater. If the
heater can be placed above the condenser
the same hotwcll pump could handle the
condensation from both.

The remainder of the valves about
the heater are for shutting it out when
operating under full vacuum. This change
is triad* with this arrangement without
stopping the main machine.

If Is Impossible to get perfect opera-

114

POWER

July 18, 1911

tion under all conditions by combining
the heater and condenser in one ma-
chine. The power determines the amount
of steam furnished and the rate is fixed
by the amount of vacuum desired to
heat the hot water for any given condi-
tion of outside weather.

When the engines are operated non-
condensing the steam connection to the
exhaust heater leads to the atmosphere
in the usual manner without a back-
pressure valve. The only reason for
using a back-pressure valve occurs when
the exhaust heater is too small and it is
desirous to raise the pressure and tem-
perature of the steam above the at-
mosphere. It is a mistake to apply a
trap or other apparatus than a pump to
the exhaust heater when operating under
vacuum unless there is sufficient fall for
the return pipe.

When the live- and exhaust-steam
heaters are connected so that the con-
densation of both is handled by a pump
and receiver the live-steam heater might
be omitted and a reducing-valve and
back-pressure valve connection be made
to the exhaust heater.

It will therefore be seen that with the
two heaters as described all the operat-
ing advantages of both a high-pressure
steam system and a low-pressure vacuum
system are obtained without their disad-
vantages outside of the initial cost of
heaters and pumps.

When the exhaust steam is below what
is necessary in very cold weather and
sufficient for average weather in the
case of a noncondensing plant it is some-
times economical to install a live-steam
heater with a drain trap, flashing the
condensation into the steam space of the
exhaust heater, with a pump to remove
the condensation at low temperature from
the exhaust heater. During periods of
moderate weather when the live-steam
heater is not required, a vacuum nearly
corresponding to the outboard tempera-
ture of the heating water may be carried.

The pumping apparatus, shown in the
figures, may be either motor driven or
steam-turbine driven. When the exhaust
of the main turbine is sufficient it is
good practice to use one motor pump
and one steam-driven pump when the
main engine is shut down. These pumps
should be of the turbine type with hol-
low bronze followers and of proper head
and capacity.

The connections should be made in
series as shown and each pump should
be of ample capacity to handle the en-
tire plant. .As it is only the expense of
one or two valves it is best to so connect
them in series that both can be run at a
time if desired. This is especially ad-
vantageous where the exhaust of a large
turbine is used under partial vacuum in
extreme weather. The average water
temperature is reduced 5 or 10 degrees,
which counts heavily on the vacuum when
near atmosphere. There is nothing gained

by connecting the two pumps having the
same head and volume in parallel as
with the frictional resistance of the pip-
ing constant for a given velocity and
varying as the square of the velocity,
the only way the discharge can be in-
creased is by placing the pumps together
in series and increasing the head.

Piston pumps have been discarded as
they are not applicable to low heads and
large volumes, and with the head bal-
anced on the discharge and suction the
valves make a racket that is heard
throughout the piping system.

Motors to be operated on centrifugal
pumps should be carefully designed for
speed and power; when direct connected
to a pump any increase in speed rapidly
increases the consumption of power and
endangers .he overload of the motor.
The pumj. operates on very high speed
for efficiency and where direct-current
motors are used special commutators
should be employed so that the com-
mutator speed will be low enough not
to spark and still take care of the nec-
essar\- current.

The apparatus should be full of water
and free of air and a pressure of 15
pounds above the static head is ad-
vantageous. It is bad practice to
pump against the static head of the
system and can easily be avoided. The
pumps should only operate against the
friction head of the piping.

The best practice is to circulate the
water as rapidly as possible at all times,
reducing the drop in temperature be-
tween the plant and the radiators and
thus lowering the average temperature of
the water.

Change the temperature of the heating
medium by varying the amount of steam
introduced into the heaters or vary the
vacuum in the case of a condensing plant
rather than the speed of the pumps and
the rapidity of the circulation. Rapid
circulation also increases the transmis-
sion of the surfaces in both the heaters
and the radiators and thereby increases
their efficiency.

It has been found by actual experi-
ment that about 80 per cent, of the me-
chanical energy of the pump reappears
in heat which is absorbed by the cir-
culated water and therefore slightly
raises its temperature. The friction and
consequent heat are caused by the rapid
movement of the water against the sides
of the pipe.

As the exhaust steam from the prime
mover of the pump is also used in the
heater it will be seen that ample circulat-
ing power is not so expensive as at first
considered.

There have been quite a number of
systems installed which use the heat
from annealing ovens and economizers
with hot-water circulation. I know of
one case where 200 horsepower in heat
units was obtained from the hot gases of
a brass furnace, a heater being con-

nected in the circuit of an existing hot-
water system. The high cost of econo-
mizers makes their use on the hot- water
heating system questionable, especially
as the high temperature of the gases^
makes them available for feed-water pur-
poses under all conditions, whereas the
heating plant does not operate in sum-
mer. The amount any economizer will
do is dependent on the quantity of coal
burned at any time under the boilers, re-
gardless of their size and the limit in
temperature of the gases that will not
interfere with the draft. Where an econo-
mizer is installed for feed purposes and
the power is inoperative at night it pays
to cross-connect it on the heating system
and it will absorb about 15 per cent, of
the heat of the coal burned at that time.
It usually does not pay to install an
economizer solely for heating purposes
due to the possible high temperature
available for feed water. However, due
to the larger volume of water passed
through it when operated for heating, the
transmission' is high.

In planning the installation of a hot-
water heating system, especially in con
nection with turbines or condensing en-
gines, the type and size of the engine
and the arrangement of the plant should
be modified to suit the hot-water system
to get the best results. This is seldom
done as the types and sizes of engines
and boilers are generally determined
upon long in advance.

With the arrangement of gages and
thermometers in the form of recording
instruments a complete daily record can
be kept of the output of the heating sys-
tem in the same manner as is the elec-
tric current. This is an important fea-
ture in keeping track of the leaks in
output in an industrial plant and cannot
be accomplished as easily as in steam-
heating systems; very few owners know
what it costs to heat their buildings. If
they have exhaust steam they generally
say it costs nothing, while with a system
as described above they could operate
condensing nearly the year around.

Alaska's Coal Unlimited

In coal resources Alaska stands
supreme along the entire Pacific coast.
There is, indeed, plenty of coal in the
State of \i'ashington, and Vancouver
island has probably more coal under it
than ever had England, but for a high-
class anthracite or bituminous coal the
present and future generations of the
Pacific coast must turn to Alaska, as
that is the only place it exists. The high-
grade, smokeless coal so essential for
the Pacific squadron of our Navy exists
only in Alaska. The future of the Pacific
coast maritime interests, as well as high-
class manufacturing industries, is large-
ly dependent upon Alaska for fuel and
for tonnage for the ships. — The Coal
Trade Bulletin. m i

July IS, 1911

POWER

115

Chicago Meeting of the Heat-
ing and Ventilating En-
gineers

At the regular summer meeting of the
American Society of Heating and Venti-
lating Engineers, held at the La Salle
hotel, Chicago, July 6 to 8, a number of
papers bearing on subjects of interest
were presented.

Paul P. Bird, of Chicago, read a paper
entitled "Some Phases of Smoke Preven-
tion." In the last 60 years the amount
of coal used for power and heating in
the United States has grown to 480,000,-
000 tons annually, about 80 per cent, of
which is bituminous. It can readily be
imagined that the smoke nuisance
brought about by this extensive use of

fore the department has no control over
this phase of the subject.

Second, the care of the firemen. This
is a matter coming only indirectly under
the department's supervision as the men
are employees of the steam-plant owners,
although cooperation is bringing good re-
sults.

Third, the equipment. Over rhis item
the city has direct control and a great
deal has been accomplished.

Draft is by far the most important
item of the smoke problem. The shortest
chimney allowed for small plants in Chi-
cago is 100 feet high, while in the largest
plants the hight is 250 feet. Records
show thi during the last administration
the smoke nuisance had been reduced
30 per cent. Practical means for further
reducing the nuisance were listed as

In addition to the usual automobile
rides and excursions to points of interest
in the city, there were a moonlight ex-
cursion on the lake, Friday evening, and
a dinner with special musical features
at the La Salle hotel roof garden.

The next regular meeting of the so-
ciety will be held at the Engineering So-
cieties building, 29 West Thirty-ninth
street. New York.

Ventilation of the ]\Iacy
Store, New York*

Bv D. M. Quay

The object of this paper is to describe
briefly the ventilating arrangements, par-
ticularly of the underground portions, of
the department store of R. H. Macy &

Plan of Subbasement of Macy Department Store, Showing Heating and Ventilating Apparatus

coal is a factor of great importance in
our modern civilization.

Comparing Chicago, plant by plant,
stack by stack, with other cities, it was
•ned to be the cleanest of any of the
'.• municipalities where bituminous
I ill is used. An outline was also given
'■i the smoke department of the city and
■ the duties which it has to perform.
;ng to the power given the department
iipervising new installations and the
'rangemcnt of old plants, within 15
rs all steam plants in the city will
'• under its supervision and a ma-
il abatement of the smoke nuisance
he made.
'• hree important items must be con-
red with relation to the smoke prob-
lem in Chicago: First, the kind of coal;
Illinois and Indiana coal must be the
principal fuels used in this district, thcrc-

electrifying of railways, the use of cen-
tral stations, boats using oil fuel and
coke, and the use of gas and coke for
heating in residences.

Mr. Bird also drew attention to the
large field for the heating and ventilating
engineer in designing heating plants for
preventing smoke and said that the prob-
lem was worthy of the most careful
thought and study.

Other papers presented at the meeting,
some of which will be abstracted in these
columns, were "New Basis for Rating
House Heating. Boilers and PVrmaces,"
by Frank I.. Biiscy; "Heating and Ven-
tilating High School Buildings In Decatur.
III.." by Samuel R. Lewis; "Ventilation
of the Macy Store in New York," by
D. M. Quay; "Notes on Tests of Warm
Air Furnace Pip'^';." by A. W. Glessner;
"Street-car Ventilation," by W. Thorn,

Co., at Thirty-fourth street and Broad-
way, New York City.

Like the average department store,
there is a basement below the ground
floor given over to retailing, this level
being low enough so that windows and
the free circulation of outside air are
inadmissible, and below this there is a
subbasement devoted partly to the me-
chanical plant of the building and partly
to the shipping and delivery departments.
In the present case not only are the base-
ment and subbasement supplied with
pure air delivered positively by incchan-
ical means but an air supply is given to
the main floor.

The accompanying plan drawing of
the subbasement will assist in showing

•Al»'<(rnrt of n piipor ri»nfl bofnr<» tlio Ampr-
nn «nrl(tv of ll>>ntln(t nnd Vcntllnllni; En
m-.T«. ChlrnKo. July It to 8.

116

POWER

July 18, 1911

the scheme of ventilation. The build-
ing has three street sides and the fourth
wall accommodates some of the eleva-
tors and the large fresh-air and exhaust
flues. The air is ta!cen from a point
above the roof level and is carried down
a 12x24-foot shaft. At the subbasement
the air may be passed through under-
ground passages with tempering coils
bypassed at will in the usual way and
then reaches two pairs of 160-inch steel-
plate blowers, four in all, which dis-
charge the air through ducts for the
supply of the subbasement, including
the engine and machinery rooms and the
basement and the first or main floor.

There are two main fresh-air discharge
ducts, one from each pair of blowers,
the first supplying the north side of the
building and carried under the basement
floor; the other is along the subbasement
ceiling along the boiler, engine and ma-
chinery walls to the east end where it
is carried around parallel to the south
wall. Finally both are extended to the
ceiling of the basement to supply air
delivered for reheating coils at the main
entrances, of which there are three, one
at the northeast corner, one in the east
center and one at the southeast corner.
The supply of air under the slight pres-
sure serves to prevent an inrush of cold
air with the opening of the doors.

The various fresh-air branch ducts
from the main ducts supply the sub-
basement and the first story, with re-
heating coils in connection with each
branch duct, except those for the engine,
boiler and other rooms of the mechanical
plant which develop more heat than is
necessary for warming purposes. The
tempering coils and reheaters are regu-
lated by the Johnson system of automatic
control. The automatic control of re-
heaters regulates the temperature as de-
sired in different parts of the store, each
such reheater being under the control
of a separate thermostat.

The basement and first story are most
crowded toward ihe central portion, and
with this point in mind the system was
designed in connection with these floors
to deliver the air to the central parts in-
stead of to points along the outside walls.
This was done by placing grills on the
fronts of the counters carrying the
branch ducts on the ceiling below, along-
side the deep girders, to outlets in the
counter fronts. The air risers are marked
A on the subbasement plan. In the stove
and household-goods department in the
basement, however, large registers were
placed in the floor in an out-of-the-way
place, as there are no permanent count-
ers in this section of the store.

A mechanical exhausting system is
also provided which removes the vitiated
air from the boiler, engine and machinery
rooms, from the shipping and delivery
departments, from the toilet and locker
rooms and from the kitchen, laundry,
bakery, etc.. on the eighth floor. No air

is blown into the toilet rooms in except
one large room in the basement, where
about two-thirds as much air is blown
in as is drawn from the room, so that
there is ahvays a slight suction in all
the toilet rooms to prevent an uncon-
trolled escape from such rooms to other
parts of the building.

For handling the exhaust air there are
two lOxlO-foot air shafts at the rear wall
and the space around the chimney is also
used to assist in the exhaust system.
These are fitted with fans and there is
also a 12-foot exhaust fan located near
the ceiling of the engine room. This
draws air from the engine and machinery
room and discharges it through a 12x12-
foot grating to the outside atmosphere.
A 120-inch steel-plate exhauster at the
rear of the boiler room draws air from
the boiler and pump rooms and dis-
charges it into one of the exhaust shafts.

An interesting detail was developed
in connection with the power required
for driving the fresh-air blowers. So
great was the chimney effect of the lofty

62.000 square feet, and incloses no less
than 16,000,000 cubic feet of space.
There are 7000 square feet of tempering-
coil surface and indirect radiation in re-
heaters. The boiler plant is of 3020
horsepower and in the mechanical plant
there are four ,S00-horsepower and two
300-horsepower electric-lighting units,
32 hydraulic elevators; and a 25-ton re-
frigerating and water-cooling system
forms part of the plant. Some of the
other apparatus making a power demand
on the plant are four moving stairways,
the parcel delivery and conveyer systems
mentioned and a vacuum-cleaning sys-
tem. The plant also includes a garbage
and refuse destructor.

LETTERS

Improving Circulation through
Heating Coils

In a large manufacturing establish-
ment heated by exhaust steam, trouble '
was experienced in getting steam to cir-

<rn Pipes-

To Boiler

Receiving Tank of Heating System

downtake shaft tnrough which the air
had to be brought from above the roof
that motors were installed of about 25
per cent, greater horsepower than would
normally suffice.

.■\ recent test made by the chief engi-
neer of the building with thermometers
placed at different points on the eighth
floor, a large open space with numerous
windows, and also in the shipping depart-
ment of the subbasement, showed less
than 2 degrees difference in temperature
on the two floors. It was his opinion
that the air in the subbasement was as
pure as the outside air, and that it was
in constant motion in all parts of the
floor. There is no complaint of drafts.

The foregoing, of course, deals only
with the operation of the heating and
ventilating plant. The building is heated
by direct radiation, of which there are

culate through the coils on the top floor,
especially a^fter starting up in the morn-
ing.

It would take an hour or more for the
coils to become warm. The engineer hit
on a scheme which did the trick in five
minutes or less. AH returns went to a
4-inch header on a receiving tank, as
shown in the sketch. The flange F was
blanketed. The two ells were tapped for
' J -inch pipes which were inserted, as
shown by the dotted lines, in the pipes
leading to the tank A from which the
feed water was taken.

These '^-inch pipes were connected
to a live-steam pipe leading from the
boilers, .^fter starting up in the morn-
ing the engineer would open the two ''•-
inch valves above the ells and turn the
live steam into the receiving tank. This
formed a partial vacuum in the return

July 18, 1911

POWER

117

pipes and in a few minutes all the coils
would be warm. The engineer would
then close the valves and thus shut off
the live steam for the rest of the day.
.A. Rathman.
Chicago. 111.

Radiators Give Trouble

The pipe dimensions given in the sketch
submitted by B. E. Thomas in the June
13 issue of PoviER to illustrate the lay-
out of his heating system, makes it clear-
Iv apparent why the three radiators on
the second floor fill with water. The re-
turn piping is shown as ' j inch through-
out, whereas this size of pipe is alto-
gether inadequate for any part of a re-
turn system operating without vacuum,
as in the present case.

From its relative size it may be pre-
sumed that the heating coil on the first
floor furnishes a very considerable por-
tion of the total condensation occurring

the branch leadin? directly from each
member of the system should be of '4-
inch pipe. Hence, the tize of the hori-
zontal length to which the return
branches from the three upper radiators
connect, should increase from 3-4 inch
in the section most remote from the trap
to 1 inch in the middle section, and 1 ' i
inches thence to the vertical drop, which
likewise should be of 1 '4-inch pipe.

A means for drawing the supply riser
should also be provided.

A. J. Dixon.

Chicago, 111.

The system indicated by the sketch
is what is known as a "dry return" and
according to the diagram, Mr. Thomas,
after carrying his steam 80 feet from
the boiler, makes no provision for bleed-
ing the line. I would suggest that he
bleed the riser just after leaving the
reducing valve and connect to the trap.
Then I should make sure that the trap

Radiators and Piping

•,'.W.W,'Myy.-'VM/,

in the system. Also, it would seem that
I on account of its close proximity to the
source of supply, the first-floor radiator
receives its steam under a pressure
somewhat in excess of that in the hori-
zontal length of pipe which supplies the
upper radiators. These circumstances
obviously combine to choke back the
Bow of water through the quite insuffi-
cient '/2-inch vertical return pipe.

With respect to the remedy, it would
•eem that if the heaters r,n the first loor
received their s'ipply of steam from the
overhead horizontal line, a much nearer
approach to equality of pressure at the
various controlling va'vcs of the system
would be realized, thus doing away with
tile retarding influence upon the flow of
wafer from the upper-floor radiators
[wiiich the superior steam pressure pre-
vailing in the lower radiator, as origi-
nally cnnrccted. would naturally exert.
In the matter of the return piping.

is large enough to take care of the con-
densation and that it is in proper work-
ing order. When sure of these things, I
should, if the system stiil fa. led to work,
put a check valve in the return line above
the connection to the first-floor radiator,
preferably in the horizontal run.

W. A. Cox.
Albany, N. Y.

Before being able to suggest a sure
remedy, several points ought to be known,
viz.: How large are the radiators? To
what pressure is the steam reduced? Is
the trap low or high pressure? Docs
the trap exhaust against a hack pres-
sure or to the atmosphere? What capa-
city has the trap?

The sketch shows four radiators and
a pipe coil, all taking steam from a
1-inch steam pipe. Assume these radi-
ators to be of the standard four-pipe
type, 3 feet high, and from the sketch 10

sections long. Each section would con-
tain about 8 square feet of surface, or
approximately 80 square feet for each
radiator. This in turn is equal to about
304 lineal feet of I -inch pipe. There-
fore the four radiators would be equal
to about 1216 lineal feet of 1-inch pipe.
Assume about 100 lineal feet of 1-inch
pipe for the coil and again about 200
lineal feet for the 1-inch service line.
Then 150 feet of Jj-inch pipe for the
returns would be equal to about 75
lineal feet of I -inch pipe. The total
would be about 1600 lineal feet of 1-inch
pipe to be taken care of by the trap.

The capacity for drainage of a well
known steam trap of ' .-inch size is given
by the makers as 1000 lineal feet of 1-
inch pipe. Thus indications point toward
too small a trap. Before changing the
trap, however, I would change the Yi-
inch return pipe to 1 inch and reduce it
to ' J inch at the ti'ap. Then tap a J4-
inch hole in the top of the trap and put
in a '4-inch equalizing pipe. This I
think will stop the trouble. Mr. Thomas
would do well to read the article by C. E.
Squiers on page 923 of the same num-
ber of Power in regard to the equalizing
pipe as this fits his case perfectly.

George H. Handley.

Newburgh, N. Y.

While the layout of Mr. Thomas' heat-
ing system appears from the sketch to be
good, I find that globe or check valves
on the return side of the radiators great-
ly improve the control, and that an air
valve on each radiator is essential. But
these deficiencies are not the main cause
of his troubles. It is all in the size of
the pipes. Make the pipe from the boiler
to the first radiator (from right to left)
on the second floor 1 ' j inches. The
reducing valve should also be of this
size. Then 1 '4 -inch pipe should be used
from the first radiator to the end and
the branch to each radiator should be
I inch. These sizes are more or less
a guess as I do not know the capacity
of the radiators.

The fact that only the radiators on the
second floor are flooded after a few hours'
run is due to the small return pipe. I
have never seen a ' -inch return pipe in
a well behaved gravity system.

If Mr. Thomas will substitute a ^4-
inch pipe for his 'j-inch return, he will
find that the system will work much bet-
ter, and especially so if the return is
increased to 1 inch from the first Poor
down to the trap.

On the first floor the radiators do not
give trouble from flooding because very
likely the pressure in them is higher
than that in the radiators on the upper
floor, thus holding back the water that
otherwise would flow from the upper
radiators to the trap and leaving the re-
turn pipe free for their own circulation.
Alex Dolphin.

Jamaica, N. Y.

118

Available Heat to Steam
Boilers*

By T. B. Morley
According to the generally accepted
methods of determining the thermal effi-
ciency of steam boilers, methods sup-
ported by the approval and recommenda-
tion of such an influential body as the
Institution of Civil Engineers, the effi-
ciency is subject to the condition of the
fuel and air supplied as regards mois-
ture; that is to say, such an accidental
extraneous circumstance as a few days
of ivet weather previous to the boiler
trial is allowed to influence the apparent
heat economy of the boiler. Surely this
is a very undesirable state of affairs,
and indicates some need for reconsidera-
tion of the manner in which efficiencies
are calculated.

In the method of .carrying out boiler
trials, as recommended by the Institution
of Civil Engineers, measurement of the
humidity of the air supply is omitted;
but, apart from that, the arrangement of
the heat balance sheet for the boiler,
and the effect of that arrangement on the
value obtained for the thermal efficiency,
is, in the opinion of the writer, at fault,
'in the form of heat account employed,
the heat value of the dried fuel is placed
to the credit side, and on the debit side
are the heat transferred to the water in
the boiler and the various heat losses,
comprising heat carried away by products
of combustion, heat carried away by ex-
cess air, heat lost by incomplete com-
bustion, heat lost by unburnt carbon
in ash, heat lost in evaporating and in
superheating moisture mixed with the
fuel, and the balance of the account due
to radiation, unmeasured losses and er-
rors.

POWER

It is the contention of the writer that
the item heat lost in evaporating and
superheating moisture mixed with the
fuel is placed on the wrong side of the
account. It should really be deducted
from the heat value of the dried fuel in
order to find the heat actually available
for utilization by the boiler, and, of
course, it is only the available heat that
should be credited to, the boiler.

The true thermal efficiency, based upon
the available heat, will be somewhat
higher than the value as usually cal-
culated, the amount of the difference de-
pending upon the amount of the heat
items due to moisture mixed w-ith the
fuel, and also, as wi.l be seen later, to
moisture in the air supplied to the fur-
nace.

The true heat supplied to the furnace
is that due to all the processes to which
the material (fuel and moisture) placed
on the grate could be subjected, so as
to achieve complete combustion. Then
the combustion would produce the en-
tire calorific value of the combustible

•Extracts from an article In i:)igincciing.

constituents; that is, the "heat value of
the dried fuel." But it is impossible to
avoid also heating the associated mois-
ture, first as liquid, then evaporating
it and then superheating it; and the
requisite heat can only come from the
burning fuel, so that even under ideal
grate conditions the heat available for
steam raising is less than that of the
dried fuel.

The actually available heat is the heat
of the proportion of dry fuel contained
in the "fuel as fired," less the heat ab-
sorbed by the moisture during its heat-
ing, evaporation and superheating to flue-
gas temperature.

An item of heat loss sometimes in-
cluded in the heat account (not in that
recommended by the Institution of Civil
Engineers! is that due to moisture de-
rived from the combustion of hydrogen
in the fuel, which moisture also passes
away as steam in the flue gases. This
heat is, however, on a different footing
from that previously discussed, and need
not be deducted from the heat value of
the dried fuel. It is due to hydrogen in-
herent in the fuel used, whereas that
due to wet fuel is the result of a quite
arbitrary and accidental circumstance.

The following figures will show the
difference in the two methods of cal-
culation, and in their results in a typical
case:

Suppose the fuel to be coal containing
12 per cent, of moisture (*'hich is fre-
quently the case), and that the calorific
value of the dried coal is 13,000 B.t.u.
per pound, and the heat usefully em-
ployed in steam raising 8600 B.t.u. per
pound of fuel as fired, or 9800 B.t.u.
per pound of dried fuel. Taking the
boiler-room temperature as 70 degrees
Fahrenheit, and the flue temperature as
600 degrees Fahrenheit, the heat in one
pound of superheated Steam in the flue
gases is approximately 1300 B.t.u.; hence
the heat used in heating, evaporating and
superheating the moisture mixed with the
fuel is

0.12 X 1300 B.t.u = 156 B.t.u.
per pound of fuel as fired; or

156 ^ 0.88 = 177 E.t.u.
per pound of dried fuel.

According to the recommendations of
the Institution of Civil Engineers, the
heat account (dealing only with the items
in question) would be as follows:

July 18, 1911

Per
B.t.u. Cent.

Heat value of 1 lb. of fuel as fired
{ = heat value of drj- coal in 1
lb. of coal as fired — heat ab-
sorbed by moisture) =-0. 88 X
13,000— l.i6= , 11.240 100

Heat transferred to water (per _

pound of fuel as fired) 8.600 ib.o

Per

B.t.u. Cent.

H.>at value of 1 lb. of dried fuel. . 13,000 100

Ilcat transferred to water (per __

pound of dried fuel) 9,Sh)0 <o J

Heat lost in evaporating^ and

superlieatinK moisture mixed

with fuel 177 1.36

The true efficiency, taking the actually
available heat as the basis of calculation,

1?-^? X loo per cent. = 76.5 per ceitt.

too — 1.36

and the true heat account (again only
for the items in question) will be

It will be noticed that in the latter
case the heat quantities are all stated,
per pound of fuel as fired, instead of per
pound of dried fuel.

The efficiency obtained in the usual
way is thus rather more than 1 per cent,
below the true value. The difference is
small, especially when compared with the
probable errors in a boiler trial; biit
there may easily be cases in which it
would be greater, and, even though the
error be small, that is no valid reason
for adhering to a wrong principle.

Turning now to the question of mois-
ture in the air supply, any moisture en-
tering the furnace with the air should,
for exactly similar reasons, be treated
in the same way as moisture mixed with
the fuel.

The effect of a moist air supply is noj.
usually taken into account at all, but it
may have a surprisingly great influence.
In certain boiler experiments recently
reported to the Institution of Engineers
and Shipbuilders in Scotland ("Experi-
ments on the Efficiency of a Live Steam
Feed Heater," by Prof. A. H. Gibson),
the moisture carried into the furnace in
the air supply amounted to no less than
0.34 pound per pound of dried coal; the
heat required to convert it into the con-
dition in which it reached the chimney
would be about 3.4 per cent, of the heat
of the dried fuel. Hence by regarding
it as a loss instead of a necessary de-
duction from the otherwise available
heat, the thermal efficiency of the boiler
is stated as 3.5 per cent, less than it
really is. Such a conclusion points to
the necessity for measuring the humidity
of the air supplied to a boiler whenever
accurate results are desired.

It is strange that for so long engi-
neers have tested boilers, given figures
for their thermal economy and even
based arguments as to the relative merits
of different boilers on small differences
of efficiency, when at the same time they
have relied on efficiency values subject
to influences so uncertain, so entirelf
unrelated to the design of the boilers
themselves as the eff'ects of wetness io
the fuel and air supply, which means,
in many cases, the effects of our variable
weather conditions.

Aluffler explosions in a gasolene en-
gine are due to misfiring, the unbumed
mixture being delivered into the hot ex-
haust passages where it is ignited. Mis-
firing may be caused by the exhaust
valve being hung up or the stem being
bent and preventing the valve from seat-
ing properly, by the mixture being too
weak or by ignition trouble.

July 18. 1911

POWER

119

Newpowe

Siphon Water Softening and
Purif3'ing System

One type of water-softening and puri-
fying system, manufactured by William
B. Scaife & Sons Company, Pittsburg.
Penn., is an automatic continuous sys-
tem, known as the siphon system ; its
operation depending upon the action of
the siphon. It is shown in the accom-
panying illustration.

The water entering the system flows
into the siphon tank until a hight is
reached sufficient to start a flow through
the main siphon, which then continues
to flow until th'i tank is emptied. When
the main siphon begins to flow it starts
the auxiliary siphons, which introduce
the reagents into it during its period of
flow. As soon as the tank from which
the main siphon operates is emptied all
siphons stop flowing until the tank re-
fills to the point where it again starts
the siphons flowing. The harmonious
action of these siphons depends upon the
head of water in the tank and not upon
the rate of flow of the incoming water.
As the main siphon will always start
and stop under the same conditions,
the auxiliary or chemical-introducing
siphon will always operate under the
same conditions. The chemicals are,
therefore, introduced in exact proportion,
and in an exact amount to a certain
definite amount of water determined by
the strength of solution and the setting
of the valve in the auxiliary or chemical
siphon.

The cheinical siphon is fed from a
small constant-level solution tank that
is connected with the main solution or
solution-storage tank. The flow to the
constant-level solution tank is controlled
by a float to keep the head under which
the chemical siphon is operated always
the same. The conditions for the op-
leration of the chemical siphon 's, there-
1 fore, controlled only by the flow in the
jmain siphon, which, in turn, is dependent
only on the water entering the siphon
! tank.

' After the mixture of water and re-
jagents in the discharge pipe of the main
I siphon, the water and reagents arc
|dashed against a baffle located below the
jwater line in the reaction compartment
of the treating and settling tank. This
Icompletcly mixes the water and reagents.
I The discharge from the siphon is dc-
jflecfed upward and outward, so that the
jdelivcry through the slatted partition in-
to the reaction chamber is not directly
I from the siphon discharge, but by a

difference of water level in the two com-
partments of the treating and settling
tank.

As this movement of the water is in-
termittent and the discharge from the

siphon is very rapid, the level of the
water above the slatted partition becomes
higher than it is at the same instant in
the compartment over the filter, and ex-
erts uniform pressure over the entire
area of the reaction chamber and pro-
duces a movement corresponding to the
difference in head on the entire volume
of the settling compartment and through
the whole area of the wood-fiber filter.
There is little or no chance for dead
spaces, as all of the water in the entire
tank is moved simultaneously with the
flow of water at each discharge of the
siphon.

In order to prevent any possibility of

Siphon Water Softener and Purifier

120

POWER

July 18, 1911

short-circuits in the settling compart-
ment, a collecting header is placed above
the excelsior filter, the openings in
which arc so placed as to draw the water
uniformly from all parts of the settling

The Hackenberg Turbine

Probably more engineering attention
is being devoted to the design of the
steam turbine at the present time than

0

tM

f^ihim

B

<..^^£iLsL i

L

^m wM^-'^uM

i^

SIR wtiS^^^'ISSSSSPIBS!

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KACHENBERCS TURBIN£ CO,

[

K

1

Fig. 1. Turbine Connected to High-speed Generator

tank. From this header the water flows
to the hiater, boiler or wherever it is
to be used.

If clear water is wanted, a mechanical
gravity fll'er as shown in the illustration
is furnislisd to remove any suspended
matter left by the excelsior filter. Where
it is desired to discharge the water at a
hight, for instance, into an open heater,
a mechanical pressure filter can be sub-
stituted for the gravity filter.

The reagents are dissolved in the re-
agent-mi.'cing tank shown on the ground
and by a steam-jet pump or any other
means is delivered to the solution-stor-
age tank, located on top of the tank,
twice every 24 hours, or as often as may
be desired, depending upon the condi-
tions under which the system is operat-
ing.

It is sometimes desirable to make the
system so that it can be operated from
the ground, in which case a steam en-
gine, elecrric motor or water motor can
be used to lift the chemicals from the
solution-storage tank located on the
ground to the constant-level siphon feed
tank. Any excess solution is returned to
the solution-storage tank by an over-
flow.

The design can be modified to adapt
it to a great variety of operating condi-
tions, for the softening and clarifica-
tion of any water for boiler feed or in-
dustrial u?es.

The two monster White Star liners, the
"Olympic" and the "Titanic," the former
of which completed its first trip from
England to New York in June, are each
equipped with refrigerating machines of
85 tons daily capacity.

has ever been given to any other prime
mover, and among other designs which
claim the notice of the engineer and the
investor is the single-runner ten-stage

vanes projecting from the heads. The
principle upon which this turbine is
based is the use of the steam from the
circumference inward to the center,
thence outward to the circumference,
whereby each ring of vanes receives the
same steam twice in one revolution; one
ring of vanes gives two stages and five
rings of vanes a ten-stage machine. All
these rings are secured to one disk, per-
mitting small size and reduced cost of
manufacture.

Steam enters through a number of
nozzles from a chest which forms the
upper half of the case. These nozzles,
of uniform dimensions, are arranged side
by side and supply steam to both sides
of the rotor, preventing side thrust. The
thrust bearing on the governor side of
the turbine keeps the rotor in its proper
position at all times and without friction.

The steam is partially expanded in the
nozzles, and after leaving the vanes of
the first moving ring is directed by the
ring of guide vanes to the second ring
of moving vanes and so on to the center.
It then enters the center 'chest which
allows no undue expansion, but guides
the steam without contact around the
shaft to each ring of vanes in the lower
half and to the exhaust, always giving
up energy and gaining velocity from one
stage to the next. As Uie steam in its

Fig. 2. Turbine Partially Dismounted

tnrbine brought out by the Hackenberg
Turbine Company, Flushing, N. Y.

It is a compact multiple diametrical-
flow turbine of ten stages. Five rings
of vanes project from each side of a
forged-steel disk, secured to the shaft.
This constitutes the moving element, the
vanes of which revolve between the fixed

travel from top to bottom is deflected
but little from a straight downward
course, the turbine is kept perfectly
drained at all times and it is not neces-
sary to heat it up before starting.

The moving vanes as well as the guide
vanes are secured to their respective
disks in a manner insuring rigidity and

July 18, I91I

POWER

121

durability and are so assembled as to
permit each machine to be adapted to
the condition under which it is to be
used as to steam pressure, rotative speed,
etc., without making any changes in its
general construction. This means that
the same castings can be used for a
large range of units and that the effi-
ciency is very nearly uniform for all
units.

Loss from eddy currents and the pass-
age of steam from one stage to the next
and around the ends of the stationary
and moving vanes is reduced to a mini-
mum by the small clearance of 1 64 inch
on the side and 1/32 inch between rings.
Forced lubrication is provided for by a
pump attached to the governor shaft which
takes the oil from a reservoir cast in the
base and distributes it to all bearings
from which it flows by gravity back to
the reservoir and is used over continu-
ously.

Speed is controlled within 1 per cent.
between the limits of no load and full
load by a specially designed inclosed fly-
ball governor.

A reversing marine unit of 6 horse-
power has been designed which will
change from full speed forward to full
speed backward in five seconds.

Fig. 1 shows a turbine directly con-
nected to a generator designed for high
rotative speed. Fig. 2 is a view of the
same machine partially dismantled, show-
ing one set each of the moving and sta-
tionary rings, the central guiding chest
and the thrust bearing.

Stickle Thermic Valve

The Stickle thermic valve is made
with an open float v.'ith an automatic
thermostat bypass ai the top of the open
float, releasing the nh through the main
valve, providing very large air passage,
making it possible to re'ease the air from
the radiator or coil very rapidly.

SuciiuN OF Thermic Valvk

bypass at the top having an adjustable
valve-seat casing that is screwed in from
the top.

When the air and condensation are e.\-
hausfed, steam closes the thermostat by-
pass and the water is forced or drawn
out of the open float by a vacuum. Then
the float immediately rises, closing the
discharge pump, except the small groove
in the valve, which permits a slight
continuous discharge, thus releasing the
air as fast as it accumulates. When the
bucket or open float again fills, it drops,
and opens wide the valve. When the ac-
cumulated condens".;ion has been dis-
charged, the open float becomes light and
rises again, closing the valve and auto-
matically preventing any e.^cape of steam
into the return line.

A water seal is mamtained at all times
in the bottom of the tucket. It floats
with fully '_■ inch of water in it, sealing
the discharge pipe. Tins seal is down-
ward and steam will noi pass downward
through water; consequently, r.o steam
can be blown throuph by gravity or drawn
tlirough by vacuum

This valve is -lanufactured by the
Open Coil Heater ."nd Purifier Company,
502 South Pennsy'vania street, Indian-
apolis, !nd.

Solderall Pa.ste Solder

Recently a new kind of paste solder,
known as Solderall, has been placed on
the market. It is put up in a collapsible
tube and all that is necessary for its
effective use is to scrape off the surface

Fic. 3. Longitudinal Cross-section

Fio. 4. Transverse Section throik.m

In the longitudinal section (Fig. 3)
the double rows of vanes are shown, and
In the transverse section (Fig. 4) the
path of the steam from the chest, through
the nozzles, moving and stationary vanes,
the central guide box and out, is plainly
•een. The arrows indicate the direction
of flow.

The sectional view shows a casing in
which is an open float to which a valve
rod is attached. The rod is guided by
a tube extending downward into the
open float. A ring cast integral with the
top evtcnding down into the top of the
open float to prevent the valve rod from
bending. There is pr automatic air-valve

of the part to be soldered a little with a
knife, squeeze some of the soldering
paste on and apply a match, candle or
torch. When the paste becomes hot it
fuses and solders in the same manner as
the old-style soldering stick. It is madf
by the H. W. johns-Manvillc Company,

inn \Villi:llll >,lllrl Nru > ..rl (ll,.

122

Special Design of Relief Valve

This relief valve has been designed to
be installed in an exhaust pipe and opens
whenever the stipulated pressure per
square inch for v^-hich the springs have
been set is exceeded.

In order to economize head room, the
springs are placed horizontal, thus per-
mitting the valve to be placed in a pipe
line close to a ceiling or other obstruc-
tion.

The springs are adjustable to within
5 per cent, above and below the pressure
stipulated.

The valve is constructed with an auto-
matic noiseless piston which prevents
hammering. The disk is centrally guided
to place on its seat and is carefully ad-
justed and well ground in. These fea-
tures in addition to the balanced piston
prevent hammering. The valve auto-
matically opens and closes, and there is
also means for locking the valve per-
manently open.

The exhaust steam enters the body on
the under-seat side and passes through
small holes in the stationary piston B,
Fig. 2, and passing into the cylinder acts
as a very efficient dashpot, whereby the
bell C floats on the exhaust steam.

This valve is fitted to seat on the valve
seat of the valve body, but when used
on the exhaust lines from turbines where
there is no lubricant in the steam, it is
recommended that it be fitted with a
bronze seat and water seal.

The horizontal' spring "mechanism, as

POWER

SOCIETY NOTES

The Ohio Electric Light Association
will hold its seventeenth annual conven-
tion at Cedar Point, O., on July 25 to 28.
A number of interesting papers are to be
read and special attention has been given

Fic. 2. Sectional View of Valve

Fig. 1. Special Design of Relief Valve

July IG, 1911

tions. The election of officers on Satur-
day evening, July 8, resulted in the
following selections for the ensuing year:
P. M. Cusack, president; P. Stratford,
vice-president; P. J. Horan, recording
secretary; W. A. Mooney, financial secre-
tary; Bernard Cassidy, treasurer; Alfred
Schmidt, conductor; Isaac Swuner,
guard; P. J. Connolly, business agent;
P. Gilleaney, Edward J. Hanley, R.
Quann, trustees; Frank McDougal,
Joseph Kavanagh and P. Phillips, auditors.
The combined organization will be known
as Local Union No. 20, International
Union of Steam Engineers. During the
evening speeches were delivered by Matt
Comerford. W. Keogh, M. Murphy and
other prominent members. There was
an entertainment, and refreshments were
served.

NEW PUBLICATION

The McGraw-Hill Book Company an-
nounces an edition in cloth of Frederick
W. Taylor's "Shop Management." This
is a reprint of Mr. Taylor's paper de-
livered before the American Society of
Mechanical Engineers in 1903. It em-
bodies the essentials and fundamentals
of Mr. Taylor's principles of efficiency,
and has for several years been the stand-
ard work on the subject. It is now avail-
able in permanent binding for the first
time. Price, $1.50 net.

BOOKS RECEIVED

Marine Engine Design. By Edward M.
Bragg. D. Van Nostrand Company,
New York. Cloth; 172 pages, 5x8
inches; illustrated; indexed. Price,
S2.

per Fig. 1, can be applied to the angle,
globe, downward discharge through pass-
age, downward discharge side inlet, but
not to the vertical.

This valve is manufactured by the
Schutte & Koerting Company, Thomp-
son and Twelfth streets, Philadelphia,
Penn.

Principles of Industrial Engineering.
By Charles B. Going. McGraw-
Hill Book Company, New York.
Cloth; 174 pages, 6x9 inches; in-
dexed. Price, S2.

Cold Storage, Heating and Ventilat-
ing ON Board Ship. By Sydney F.
Walker. D. Van Nostrand Company.
New York. Cloth; 269 pages, 5x8
inches; 71 illustrations; indexed.
Price, S2.

to the entertainment of those attending
the convention.

Local Union No. 20, International
Union of Steam Engineers, and the Ec-
centric Association of Engineers, No. 1
of New York City, recently amalgamated
for the benefit of each of the organiza-

Practical .Applied Electricity. By
David Penn Moreton. The Reilly &
Britton Company, Chicago, III.
Flexible leather; 438 pages, 4'..x7
inches; 323 illustrations; 20 full-
page tables; indexed. Price, S2.

PERSONAL

N. B. Avers, a member of the -Ameri-
can Society of Mechanical Engineers,
has resigned as chief engineer of the
Dayton Power and Light Company and
organized the .Avers Engineering Com-
pany, to handle power-plant engineering.
Address, Conover building, Dayton, O.

W.l. 34

NEW YORK, JULY 25, 1911

No. 4

OLD SAUERFLEISCH certainly had a pat name.
The United States equivalent for sauerfleisch
is sour meat, and our "hero" was all of that.
A single glance from him was sufficient to turn per-
fectly good milk into pot cheese. Dogs never at-
tempted to be friendly with the old crust — they knew
instinctively that it was useless. To be concise,
he had the reputat on of owning the best "chronic
grouch" in six counties. He had very few sincere
friends and no one ever succeeded in developing a
pleasant acquaintance with him Only those sales-
men who were strangers in his territory called on
him and they seldom repeated the call more than
once or twice. If possible, Sauerfleisch was worse than
old Scrooge before his reformation — he seemed to hate
even himself. Certain it is that he was of very little
use to the community and but scant comfort to him-
self, for that matter. Nothing pleased him, nothing
satisfied him even. He
never was known to do a
kindly deed or say a pleas-
ant word.

About the only con-
solation that we can get
out of this sad recital is
the fact that Sauerfleisch
was not an engineer. Then,
of course, there is the
moral — we're long on mor-
als here on the front page
as no doubt you have
observed.

A pleasing contrast to
Sauerfleisch 's personality
was that of Joy Openface.
When people spoke of him,
the terms most frequently
tised were: genial, jolly,
friendly, decent, "gf)Ofl
scout," good fellow and
such like. He always had

a friendly greeting, a cheering word, a sympathetic
ear or a helping hand for anyone he might meet. In
addition to this there was an indescribable something
about him that caused one to feel instinctively that
he was a friend. Not many of us are blessed naturally
with this quality, but many succeed in . creating a
satisfactory substitute by careful self-training and
by exercising self-control. When instinct and natural
inclination prompt open hostility toward some
stranger or even an uncongenia' acquaintance, self-
control dictates the use of dignified civility at the least

Old Sauerfleisch found life a continual strife,
full of unpleasant encounters. His frequent plaint
was that ever\'one antagonized him without cause.

With Openface it was the reverse. When the
occasional need arose he always found a dozen or
so to give him a boost over a rough spot.

Each reaped the na-
tural fruit of his sowing.

There are many, many
reasons why it pays to cul-
tivate the habit of being
open to friendly advances.
It is easy enough to drop
a man who does not prove
to be worthy of your con-
fidence and fricndshi[), bi:t
it is often really diflicult to
develop an intimacy with a
good man — one who woti d
make a valuable friend
once you have shown your-
self unresprmsivc to his
advances.

"Glad handing" is the
description sometime ^
given of the practice of
being open and cordial.

Being a disciple of the
"glad hand" is not such a
bad idea.

POWER

July 25, 1911

Hydroelectric Plant at Vernon, Vt.

About two years ago the Vernon, Vt.,
hydroelectric power plant of the Con-
necticut River Power Company was
partly described in Power, the plant then
being in process of erection. All of the
machinery has since been installed and
the transmission lines have been com-
pleted.

The building has a steel skeleton
framework with concrete substructure
and brick superstructure. It is 250 feet
long by 55 feet wide inside and contains
eight generating units.

The power house forms part of the
dam, as shown in Fig. 1. From the east
end of the building the main dam ex-
tends to the east bank of the river and
forms a spillway 600 feet long. The
dam is of concrete built on rock founda-

This installation consists
of eight 2 ^oo-kiloiiutt gene-
rators, each driven by three
turbine wheels mounted on
the same shaft. At the nor-,
mal water level two wheels
are active and the third and
top wheel is put into service
during flood periods when
the effective head is reduced.

With the water at the crest of the dam,
a pond 16 miles in length is obtained
and with 4 feet of flashboards on the
dam, which are generally used in the

generators deliver three-phase 60-cycle
currents at 2300 volts.

There are two exciting units which run
at a speed of 190 revolutions a minute
and deliver 2400 amperes at a voltage of
125. The speed of these exciter tur-
bine wheels is governed by Lombard gov-
ernors.

The waterwheel equipment for each
generator consists of two 60-inch Mc-
Cormick turbines in one wheel case at
the bottom of the wheel pit. These two
wheels in regular operation at normal
head give sufficient power to drive the
generator at its rated capacity. During
the flood period the effective head is re-
duced so that a third wheel has been
added above the other two, as shown
in Fig. 4. Under all conditions of water

Fig. 1. Looking at the Power House from Below the Dam

tions, and gives an operating head of
about 34 feet.

Ten flood gates are arranged through
the base of the dam, and when flooded
each gate will discharge about 2000
cubic feet of water per second. These
7x9- foot gates are motor operated and
can be opened in about two hours. The
motor is reversible and is also used to
close the gates.

summer time, water is backed upstream
about 31 miles. The area of the water-
shed above the dam is 6250 square miles.
Waterwheels and Generators
As one enters the door of the main
generating room he sees eight General
Electric generators installed in a row
as shown in Fig. 3. each having a nor-
mal capacity of 2500 kilowatts and run-
ning at 133 revolutions per minute. The

the full rating from each generator is
obtainable. The Lombard governors are
of a type especially designed for this
installation and are capable of giving full
travel of the gates in I'S seconds; they
control the lower pair of runners only.
The gate on the upper runner is manipu-
lated by hand.

The entire weight of the waterwheels,
vertical shaft and revolving field of the

July 25, 1911

POWER

125

generator is supported by a thrust bear-
ing located in a chamber directly below
the generators. Each unit has an in-
dependent triple-plunger oil pump sup-

The oil from the step bearing passes to
a filter and from that to a supply tank
from which the oil pumps take it to the
step bearing. Oil for the main bearings

outfit which is driven by the exciter unit
and is used for supplying step-bearing
oil to the generator units when they are
about to be started. As soon as a gen-

FiG. 2. General Plan of Station

plying oil to its bearing at from 150 to on the vertical shaft is obtained from erator has come up to speed and its in-

250 pounds pressure. An auxiliary pump an overhead supply tank and after pass- dividual pump is capable of maintaining

connected to an auxiliary oil header ing through a filter it is elevated to the a proper step-bearing pressure the auxil-

furnishes oil for starting and stopping, overhead tank, the cycle being con- iary step-bearing pump is stopped.

Fig. 3. The Generator Room

This thrust bearing is the only support tinuous. Each waterwheel is supplied A signal system is used for starting
for the revolving element of each unit, with a step-bearing pump which main- and stopping the various units. For in-
weighing about 85,000 pounds, and has tains an oil supply while the waterwheel stance, if the operator in the generator
•0 far worked out very satisfactorily, is in operation. There is also a pumping room desires to start No. 1 turbine, he

126

POWER

July 25. 1911

rings one bell as a signal to the step-
bearing pump man who is stationed in
the room below, shown in Fig. 5. At the
same time one of eight switches is thrown
which illuminates the "figure I" on
the signal board in the step-bearing room
and another switch illuminates the word
"start" on the same board. As soon as
the step-bearing operator receives this
signal he starts the auxiliary step-bear-
ing pump. The attendant then throws in
a duplicate switch which illuminates the
word "start" and the "figure 1" on a
signal board in the generator room.

Transformers

Four 5000-kilowatt, three-phase trans-
formers are installed, each in a separate
brick compartment, which raise the pres-
sure from 2300 to 66,000 volts, the nor-
mal operating transmission voltage. An
additional 900-kilowatt transformer is
installed for transferring energy to a line
reaching nearby territory at 19,000 volts.
All the oil switches are of remote con-
trol and electrically operated, so that
the switchboard panels contain control
switches with pilot lamps and the neces-
sary instruments, all operating at low-
voltage.

Fig. 5. Step-bearing Room Showing Step Bearings of the Various
Generators

Fig. 4.

Elevation of the Plant Showing .Arrangement of the Three
Turbine Waterwheels

The general wiring arrangement is
such that a pair of generators are con-
nected to a 5000-kilowatt transformer
which is either connected to a 66,000-
volt bus or to an individual transmis-
sion line. This keeps the 2300-volt wir-
ing down to the lowest possible amount,
although a 2300-volt bus is provided so
that in an emergency any generator can
be connected to any transformer. Each
generator, transformer and line is pro-
vided with automatic inverse time-limit
relays for protection against short-circuit
or serious overloads.

Above the transformer rooms in the
gallery running the entire length of the
station are located the oil and knife
switches.

To facilitate the handling of heavy
machinery a 60,000-pound electric crane
running the length of the building has
been installed. A spur track enters the
station for a short distance so that ma-
terial can be unloaded from the cars and
carried to any section of the plant by the
crane. At the far end of the plant there
is a motor-driven Clayton air compressor
driven by a I5-horsepower motor. It is
used to furnish compressed air for clean-
ing purposes such as blowing dust out of
the generators, etc.

SWiTCH BOARD

Midway of the generator room is the
black marble switchboard, which is
made up of eight generator panels, eight
transformer panels and two exciter
panels. There is also one panel for the
lighting line of the plant and one motor
panel for controlling the circuit running

July 25, 1911

POWER

127

to the motors in the basement. A plan
view of the plant is shown in Fig. 2.

In the basement in a room separate
from the step-bearing room and extend-
ing the length of the building are found

ing switches for testing purposes. A
ground wire of No. 4 copper-clad, steel-
core wire is stretched over the entire
line and is attached to the apex of the
tower above all transmission wires.

Fic. 6. Construction of Junction Toixer

the busbars, from which the transformer
wires and the lines lead. In this room
there are also two large oil tanks -Ahich
are used in preparing the transformer
oil and the oil used in the step bearing.
Trans.viission Lines
On the top of the building are placed
three lightning-arrester towers, from
which the main transmission lines ex-
tend in a southeafterly direction through
the towns of Vernon, Hinsdale, North-
field, Warwick, Royalston, Winchendon,
Gardner, Fitchburg, Leominster, Sterling,
Clinton, West Boylston and Worcester.
They consist of two three-phase circuits
on steel towers of from 40 to 60 feet in
hight, set in concrete, each tower being
sufficiently stable to carry its load under
all weather conditions, even if all the
wires in one span should break.
I Each circuit is composed of three-
i siranded copper conductors of No. 2
Brown & Sharpe gage, about 'i inch in
diameter, and has a carrying capacity of
10,000 horsepower at 5 per cent. loss,
i In an emergency, one circuit would carry
^the entire load, although at somewhat
greater loss.

The porcelain insulators are of the
pin or vertical type, consisting of four
separate parts or shells cemented to-
gether, the outside diameter being 15x14
inches in hight and weighing about 35
pounds each. Each insulator has been
tested at 180,000 volts.

About every ten miles is placed a
I junction tower, one of which is shown
In Pig. 6, where are located sectionaliz-

every tower being permanently grounded
to secure protection from lightning. A
private telephone line is installed over
the entire line, with instruments at each

The total length of the line is over 66
miles and is divided into six sections
for purposes of patrol, each man having
from 10 to 12 miles to cover on fool
twice each week.

As there are 885 towers on the line
(exclusive of a branch line) this gives
an average spacing of 410 feet between
towers, although there are a few larger
spans, notably that over the Wachusett
reservoir of 1940 feet.

If it is necessary to change or re-
place an insulator, which work is usually
done at night or on Sunday, the entire
load is thrown onto one line, the other
line is opened at both ends and all three
wires arc grounded on the tower on
which the work is to be done, thus en-
abling the men to work in perfect safety.
The patrolman either disconnects the
section of the line at the junction towers
or more often telephones the .power
house and substations that he is about
to work on a certain line. Then all the
operators place tags on the switches con-
trolling this line and state the time the
line is ordered off, the nature of the
work to be done and gives the name of
the man ordering the line off; no op-
erator will energize this line until the
same workman has ordered all the tags
removed.

Substations are located at various
towns, one of which is shown in part in
Fig. 7. From this substation electrical
energy is delivered to manufacturing
concerns, electric-light companies, etc.

Fir,. 7. Partial View of One of the Substations

substation and junction lower, where a
small house is erected to receive the
telephone and a supply of repair material
and tools for emergency use.

It is the practice of the company to
carry feeders to the premises of its
customers and require them to install
all apparatus for the conversion of the

128

POWER

July 25, 1911

energy to suit their individual needs.
Usually disconnecting switches are in-
stalled at the entrance point of each in-
stallation and there the company's re-
sponsibility ends, except that it provides
all metering equipment. Both integrat-
ing and graphic wattmeters are installed
for each customer, so that from the rec-
ords the characteristics of each cus-
tomer's load are known.

Synchronous motors are installed on
the system amounting to about 4000 kilo-
watts in capacity, thus giving an op-
portunity to correct the power factor
on the system. As a matter of fact the
average power factor at the Vernon sta-
tion is about 90 per cent.

Contracts

The flow of the Connecticut river
varies with the seasons so that at cer-
tain periods there is an abundance of
water and less at other times. There-
fore two classes of contracts, termed
primary and secondary, are made. Pri-
mary contracts guarantee to deliver to
a customer the amount of power for
which he contracts. Under secondary
contracts the right to cut off the supply
on reasonable notice is reserved, but
giving the customer the opportunity of
starting his own steam plant and carry-
ing his own load. Naturally, under the
secondary contracts electrical energy is
sold at a lower price than is charged for
prim.ary contracts.

Reciprocal contracts have been made
with some of tlie large customers whose
steam plants have been shut down,
whereby the plants are held in readiness
for operation and the company has the
privilege of operating them when neces-
sary, turning energy into its own sys-
tem. These contracts are advantageous
as avoiding the necessity of building an
auxiliary steam plant to guard against
possible extreme flow in the Connecticut
river.

A contract has also been made with
the Metropolitan Water and Sewage
Board for the output of the hydraulic
plant which the board is about to build
at Clinton. In this situation the water
from the Wachusett reservoir is de-
livered to the aqueduct leading to the
Boston system and additional power can
be developed at this point. It is planned
to install four lOOO-kilowatt generators,
three of which will be used normally
with the fourth one held in reserve. In-
asmuch as this reservoir is usually drawn
on in the summer time, the Connecticut
River Transmission Company can use this
power during the periods when it would
naturally experience low water in the
Connecticut river.

It is not altogether what is in the coal
but what can be got out of it that makes
it valuable as a fuel to the power-plant
owner.

Hydraulic Hammer Test for
Boilers

By J. E. Terman
Most readers of Power are familiar
with the hammer test as used in in-
specting steam boilers and also with the
hydrostatic test for the same purpose,
but probably few are acquainted with a
combination of the two, or what might
be termed a "hydraulic-hammer test"
which was once recommended to me as
the best and surest method of determin-
ing the safety of a boiler. I was at the
time inspecting boilers for an insurance
company in the South, and after a day's
work on a sugar plantation went to its
general store to while away the time
between supper and bed time, and also
for the purpose of getting the owners
(who also operated a sawmill) sufficient-
ly interested to consent to insure their
sawmill boilers as well as those at the
sugar house. The usual crowd of over-
seers and hangers-on were ranged on
soap boxes around the stove in the rear
of the store, ready to discuss any sub-
ject that might be broached. The saw-
mill manager was one of the group, and
after the presentation of the customary
cigar I proceeded to give him the inside
facts regarding the numerous advantages
to he gained by having his boilers and
plant regularly inspected by a mechanic
who devoted his entire time and talents
to this one class of work. Great pains
were taken to describe in detail the
thoroughness with which the inspections
were made and how the experience
gained by the inspector could be ob-
tained in no other way, and that he was
thereby enabled to detect defects and
dangerous conditions of operation that
would ordinarily escape the notice of
an engineer.

About the time the sawmill manager
was beginning to weaken under the con-
tinuous presentation of facts, a bystander
( who proved to be the man in charge of
one of the skidder outfits used in pull-
ing the logs out of the swamp) entered
into the conversation. He said: "Young
man, it may be all right to crawl through
the biler like you tell about, and lamm
its insides with a tack hammer, but I
can tell yer that yer are wasting yer
time. I never look inside a biler to tell
whether it is good to hold steam or not,
but I always tests a strange biler my
way to be shore that it is all right be-
fore I fire her up."

1 told him that I was greatly interested
in what he said, for there were many
inspectors throughout the country wearily
dragging themselves through boilers
every day in an endeavor to determine
whether they were safe to carr\- pres-
sure or not, and if he could recommend
a more effective method that would do
away with this laborious feature all in-
spectors would look on him as a bene-
factor. "Well, this is the way it is done,"

he said. "You first fill the biler plumb
full of water, clear up to the top, and
then yer shut all of the valves tight, and
git a sledge hammer (about ten pounds
is the right heft) and yer belt the biler
a good stiff one on the side, and if she
don't bust, she is all right."

I was compelled to admit that if a
boiler was entirely filled with water and
could withstand such treatment without
breaking, it undoubtedly indicated that it
possessed staying qualities, at least be-
fore taking the treatment, but I was able
to thoroughly convince the sawmill man-
ager that his boilers had best be given
the hammer test in homeopathic doses
with a tack hammer, as my friend de-
scribed it, and not be belted in the sides
with a lO-pound sledge.

Boiler Explosions in England

The following extract from the report
of the Committee of Management of the
Manchester Steam Users' Association in
England is of interest, as it shows what
may iie done by careful and rigid in-
spection toward reducing the number of
boiler explosions and the resulting
fatalities:

"As many as 22,656 examinations were
made of ooilers during 1910, including
feed-water heaters or fuel economizers,
9675 of these being 'internal.' 'flue' and
'entire' examinations, the highest num-
ber ever yet recorded.

"The firebox of a locomotive crane
boiler enrolled with the association had
collapsed and rent during the year, re-
sulting in personal injury to several
workmen. The matter, the report stated,
was still under investigation, with a view
to determining the actual cause, which
could not at present be stated. At the
end of 56 years' working the committee
was able to report that no life has ever
been lost by the explosion of any boiler
under the association's guarantee.

"Outside its ranks the association had
recorded, during the year 1910. the oc-
currence of 85 explosions, killing 20 per-
sons and injuring 71 others. Of these,
24. killing 9 persons and injuring 34
others, may be termed 'boiler explosions
proper,' while the remaining 61. killing
11 persons and injuring 49 others, may
be termed 'miscellaneous explosions' —
those arising from steam pipes, stop
valves, kiers, drying cylinders, bakers'
ovens, etc. In addition to the above, one
explosion arose from the bursting of a
kitchen boiler, by -.vhich one person was
killed. These figures are higher than for*
several years past, tut in many cases the
explosions were of a comparatively (
trifling character, though subject to in-
vestigation under the provisions of the
Boiler Explosions acts, 1882 and 1890."

A record of 56 years without a single
fatality from boiler explosions is indeed
remarkable. Just imagine the opportun-
ities presented to a similar association
in this country.

July 25, 1911

POWER

129

Notes on the Design of a Drip System

The design of a piping system for a
modern steam-power plant requires a
thorough knowledge of working condi-
tions obtained by actual experience in
erecting and operating the various ap-
paratus of which a plant is composed.
It is also necessarj- that practical ex-
perience be supplemented with a com-
prehensive knowledge of mathematics,
physics and applied mechanics in order
to obtain the best possible results, viewed
from the standpoint of safety, economy
of operation and durability.

Attention to the design of the drip
system of a pianl has a more direct bear-
ing on the safety of operation than all
of the safety devices on the market. Yet
the safety devices are usually applied
to the drip end of some apparatus, and
their operation is contingent on the ar-
rangement and capacity of their dis-
charge pipes. Most engineers will agree
■ that a large percentage of the troubles
is caused by inadequate or improperly
arranged drip pipes.

There are many cases where the trunk
line is too small, and when one trap
is discharging it blocks off all the rest

Bv J. P. Lisk

The drip system as now in-
stalled in a certain high-
pressure steam plant is
described and its dejects are
pointed out. A revised ar-
rangement of drips is also
submitted, in which the ex-
isting defects are eliminated.

mission and four men were seriously in-
jured. The arrangement that was made,
and the one that should have been made
under the existing conditions, in connect-
ing up a high-speed Corliss engine is
shown in the accompanying illustrations.
These are sectional elevations through a
portion of the engine room of a recent
installation, according to the plans and
specifications of an expert consulting
engineer.

a vertical recsiver-type steam separator
which is joined in the most rigid manner
possible to the throttle valve. A more
flexible-proof, strain-producing arrange-
ment would be hard to devise. Angle
valves should never be used in this or
similar positions. They are not looked
upon by the manufacturers as unquali-
fiedly successful in high-pressure steam
work in sizes larger than 3 inches in
diameter.

Fig. 2 is a much better arrangement
for the same connection. Starting from
the 6-inch outlet on the header with a
pair of flanges having a nipple between
to make a swing joint, a long-radius ell
is added, and to this is attached a
straightway valve, immediately follow-
ing which is a horizontal steam separator.
From the outlet of the separator there is
a compound bend to the top of the throt-
tle valve, which makes the second swing
joint in the flange on top of the valve.
The entire connection would be as flex-
ible as it is possible to make it and be
steam tight.

In the system as laid out in Fig. 1,
the only drip from the 160 feet of supply

■ Fumpm<j Trap wifh High-pressure

Pre. 1.

Steam Connection

Piping As Installed

Fic. 2. Piping As It Should Have Been Installed

of the drip line?; also, when certain by-
passes are opened, high-pressure steam
gets into the low-pressure lines, causing
water to block up into places where it is
quite likely to do severe damage. The
writer knows of three plants in which
the high-pressure steam drips were in-
advertently bypassed into the low-pres-
sure lines. One of these resulted in a
2400-horscpowcr cross-compound engine
having its frame broken just in front of
the guides, the crank pin sheared and
the main rod twisted. Another 80-horsc-
power Corliss had its reciprocating parts
wrecked, and in the third instance the
entire engine rootn was put out of corn-

Fig. 1 shows the plant as it was in-
stalled. The engine is an 18x30-inch
Corliss, running at 150 revolutions per
minute and driving a 205-kilowatt gen-
erator. Steam is supplied at 100 pounds
pressure by horizontal tubular boilers
located approximately 160 feet from the
end of the header, shown at the right
side of the drawing. There is a decided
objection tu the manner in which the
6-inch steam connection is run to the
engine; a long-necked angle gale valve
is bolted rigidly to a nozzle welded to
an 8-inch pipe; from the top outlet there
is a 6-'nch extra-heavy 90-dceree pipe
bend with extra-heavy fittings leading to

main is the I '4-inch pipe running to
the high-presstire steam trap located as
shown at the left of the engine. This
also takes the drip from the steam sep-
arator, and from the heel of a 2'2-inch
high-pressure line running to a remote
part of the building to supply steam to
a type foundry. The steam supply to
operate the pumping trap shown in the
pit is also taken from the same I'l-inch
outlet. This anangcmenf brings all the
water of condensation from the 160 feet
of 8-inch pipe, equivalent to 329.6 square
feet of condensing surface, to a point
directly under the 6-inch branch to the
engine, where there occurs a right-angled

130

POWER

July 25, 1911

change in the direction of the current
of steam flowing at a high velocity. This
results in a large portion of the water
which should be taken care of by the
drip line being broken up into spray and
carried to the separator. As a result, the
separator is greatly overloaded, its effi-
ciency is reduced and a large amount
of water reaches the engine. This water
by actual test amounts to 138 pounds
per hour.

Disregarding the resulting operating
difficulties, the question mav be asked:
"Where is there any loss?" The con-
densation will take place in the long
steam line just the same, regardless of
the drip arrangements. To a certain ex-
tent this is true, but in the one case clean
water is carried back to the boiler at a
high temperature, and in the other the
oily v/ater must be thrown away. When
the feed water comes through a meter
and the price of coal is high, 138 pounds
of boiling water per hour going to the
sewer will amount to an appreciable item
for each montli of operation.

While the dnp piping of this plant is
tad on the steam side, it is still worse
on the exhaust side of the engine. Re-
ferring 10 Fig. i, the exhaust pipe drops
from the exhaust outlet about 20 inches,
t'Ten crosses over to a tee at the foot of
the riser, which extends upward about
9 feet and then runs horizontally about
18 feet to the ii;ain 12-inch exhaust line.
There is a gate valve in the riser, and
an oil separator in the top horizontal
run, about 4 feet from the ell on the
vertical line. From the bottom of the
tee on the riser there is a 1 '4 -inch nip-
ple with a bull-head tee, one side of
which receives the drip from the oil sep-
arator, the other being connected to the
receiving side of a high-pressure return
trap. The discharge from the trap is
carried up to a point over the horizontal
exhaust line and thence to the sump,
110 feet from the trap pit. The pit being
4 feet lov/er than the sewer, there is no
chance to get rid of waste water except
by the use of a hand pump and bucket.
Unfortunately, the excavation for the en-
gine foundation was not waterproofed,
and some water veins, that gave consider-
able trouble when the building was con-
structed, have found an outlet into the
wheel and trap pits. It is now necessary
for the engineer to give close attention
to these places and see that water does
not accumulate in a sufficient quantity
to destroy the main belt or put the trap
out of commission.

An especially bad feature of the drip
system is that of placing a return trap
in the position shown, as the only means
of taking care of the drips on the ex-
haust side of a high-speed engine. The
trap itself is all right in the work for
which ;t was designed, but in this case it
is entirely out of place, being required
to handle the oil discharged from the
oil separator as well as the drip water

from the engine. Furthermore, failure
to operate is ap: to be accompanied by a
wrecked engine with possible injury to
the attendants. Engine builders, as a
rule, object to a trap of any kind between
the exhaust side of their engines and the
atmosphere. The writer has never known
of an instance where the builder woj'd
turn a new engine over with a trap-
closed drip until someone in authority
would .issume ail responsibility for any
damage that might directly or indirectly
result from its being so connected.

Now for a short study of the piping
as arranged in Fig. 2. The manner of
making the 6-inch steam connection with
the swing joints has been already re-
ferred to. About four feet from where
the engine branch rises to the separator
a drip leg has been inserted and con-
nected ta a trap so that all of the con-
densation taking place in the main may
be returned to the receiving tank and
heater without the possibility of a large
portion of it having to pass through the
steam separator. The main has also
been extended 30 inches beyond the en-
gine branch in order to obtain a cushion
effect to help lessen the vibration induced
by the pulsations of the steam passing
to the engine.

The high-pressure drip system for the
water leg and the separator are entirely
independent of each other up to the
trunk-line discharge pipe, and that is ar-
ranged to deliver to the return tank or,
in an emergency, to the sewer. Another
feature worth passing notice is that all
water wnich gathers in the main when
the engine is out of service and the stop
valves on the boilers are closed, may be
removed by gra\ ity. The high-pressure
line to operate the ejector and drip tank
is taken irom the top outlet of the cross
above the drip leg, and in such a way
that there is no possibility of any water
being carried over to interfere with the
proper operation of that apparatus.

The manner in which the drip water
from the exhaust pipe and oil separator
is handled is, under the conditions, all
that could be desired when viewed from
the standpoint of efficiency, economy and
safety. The sump tank is 36 inches in
diameter by 36 inches high, made of
5 '16-inch steel plates, and in the top
head there is a 20-inch opening, fitted
with a cover securely bolted on. In this
cover directly over the operating end of
the ejector is a hole tapped for a 3'/j-inch
pipe and closed with a brass plug, which
may be readily removed and a drop light
let down into the tank for inspection.

When it becomes necessary to make
repairs to the mechanism of the ejector,
which dots not happen very often, the
cover may be removed and replaced
again with but very little work and with
the ordinary tools found in every engine
room. Within the tank there is a steam-
operated ejector, the valve of which is
operated by a float. The tank is so piped

that all of the drip water from the en-
gine exhaust and from the oil separator
flows into it by gravity. When a certain
level, indicated by A A, is reached the
float turns on the steam valve of the
ejector and the water is forced out of
the drip tank into the blowoff tank,
which is located at a higher level, and
thence ;o the sewer. When the water
reaches the lowesi point at which the
ejector is set, the float closes the steam
valve and the ejector ceases to work until
the high level is again reached.

The ejector, as shown, is within the
tank; high-pressure steam is brought
from the main header to the ejector,
passing through the shell of the tan.'c
and having a union between the ejector
and the shell, all made steam tight so
that the high-pressure steam may not
escape *o the tank through this connec-
tion. There is also a branch from this
high-pressure line connecting directly
with the tank. Each branch has a con-
trolling valve so that high-pressure steam
may be supplied to the ejector or to the
tank as desired. From the bottom of the
tee in the main exhaust pipe and from
the drip outlet of tiie oil separator a drip
pipe is carried through the shell of the
tank and then turns down. This arrange-
ment allows all of the oil coming to the
tank to drip free of the piping and also
get to the surface of the water without
having to be forced through it.

In addition to the automatic opera-
tion of the tank it may be worked by
hand in an en;ergency in the following
manner: When the tank is nearly filled
(which co.idition may be determined by
a try cock* the valves in the drip pipe
from the separator and the exhaust loop
are closed, as is also the direct discharge
from the ejector. The valve in the dis-
charge branch from the bottom of the
tank is then opened first, after which the
valve in the high-piessure connection at
the top is opened. The contents of the
tank will immediately be driven through
the discharge pipe to the blowoff tank.
After the tank has been emptied, which
will probably require about two minutes,
the valves are leadjusted for the regular
service.

As before mentioned, the amount of
water passing through the trap under
present operating conditions is 138
pounds per hour, which would be very
much decreased with the system shown
in Fig. 2. The periods for emptying
the tank, which at three-quarters full
and at a temperature of 200 degrees con-
tains 954 pounds, would be 6.9 hours.
When the tank is blown out in the man-
ner mentioned, any accumulation of oil,
or any other foreign matter contained in
the drip water is also removed. It is a
good plan, under normal conditions, to
blow down once a month at least in
order tn keep the entire drip system
clean and in as good working order as
possible.

July 25, 1911

POWER

Temperature Conversion Chart

The accompanying diagram offers a
convenient means of conversion between
the three temperature scales in use and
from which six transpositions are de-
rived. In electrical work frequent use
is made of the Centigrade scale, and con-
version into degrees Fahrenheit is fre-
quently necessary for reference and re-
cording purposes.

The Centigrade thermometer is em-
ployed wherever the metric system is in
use and, owing to its simpler form of
graduations, its application is greater in
extent than the Fahrenheit scale. It es-
tablishes the freezing point at 0 de-
grees and the boiling point at 100 de-
grees, making the divisions thereby ob-
tained exactly 100, corresponding to 180
on the Fahrenheit scale, which places
the two extremes at 32 and 212 degrees
respectively.

20 40 60 80

By Le Roy W. Allison

A chart showing the rela-
tion between the three tem-
perature scales, namely, the
Fahrenheit, the Centigrade
and the Reanmnr. By its
use any one of the six con-
fers ions betiveen tltese scales
is readily obtained.

The formulas for conversion

are:

F = 2c-f3.

(>)

F=lR-^32

(2)

C=(F-3.)|

(3)

4

(4)

R = (F-,2)i

(5)

A' = ic

(f)

between ihe three scales, and from the
respective boiling points the existing
ratios are derived. Representing tem-
perature Fahrenheit by F, temperature
Reaumur
120 140 160 180 200 220 240 260 280 300

The tnree curves of the diagram cover
the six conversions in a range suitable
for ordinary use and capable of any ex-
tension. \ practical example will illus-
trate the application.

Assume that a generator guarantee
gives a full rated load with a rise in

320 340 360 380 400 420 440 46Q

-40 -20 0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 JOO 320 340 360 380 400 420 440 460

Fohrenheit

Conversion Chart

The Reaumur is commonly referred
to as the Gern;an scale and is the stand-
ard in a few countries; in America its
greatest use Is possibly for such work
M distilling and brewing. It represents
the freezing point at 0 degrees and the
boiling at 80 decrees.

The conversion chart is obtained from
the usual fonnulas giving the relations

Centigrade by
Reaumur by R,

One degree C ■

C, and temperature

ISO 9 . E-

loo 5 ='

One dcqrce R = - = - degree f F
One degree /^ = - ^ - degrees C

temperature not exceeding 40 degrees
Centigrade and degrees Fahrenheit are
desired.

By formula ( 1 )

/=- = ^X 40 + 32^

104 degrees

Referring to the ch.irt, the known
Centigrade temperature is found at the

132

POWER

July 25, 1911

right-hand scale, the intersection of the
abscissa marked 40 with that of the line
marked Fahrenheit-Centigrade gives the
corresponding Fahrenheit-degrees tem-
perature, the reading being obtained from
the divisions at the bottom, marked 104.

The left-hand scale marked Fahren-
heit is used when conversion to Fahren-
heit from Reaumur or vice versa is re-
quired, and is applied in conjunction
with divisions along the top marked
Reaumur.

The diagram as shown is easily plotted
and may be mounted on cardboard or
otherwise for handling and preservation.

Cylinder Oil Consumption

Tests

By W. T. Heck

The engineering laboratory of Purdue
University has two engines which are
used for experimental purposes only,
one being a noncondensing Vl^xlS-inch

under test conditions for a half-hour,
and between the tests it was allowed to
run 10 minutes under the changed con-
ditions before readings for the succeed-
ing test were taken. All operating condi-
tions were maintained constant on the
various tests, the only change being the
feed of the lubricator. All bearings were
kept well oiled on all tests by sight-
feed cups that no variations might oc-
cur in that part of the engine friction.
The steam used in the laboratory is
usually of about 98 per cent, quality and
it may be considered as practically dry
steam after passing the separators of
the two engines.

The results obtained are as shown in
the tables.

The cylinder oil used in these tests
is purchased at 28^^ cents a gallon in
barrel lots.

The tests might be said to be too short,
and that a half-hour is not sufficient time
to allow conditions of cylinder lubrication

FRICTION TEST OF BUCKEYE ENGINE

Quantity of oil

Temperature of engine room, degreesF

Date of test

Speed of engine, r.p.m

Steam pressure, pounds gage

Indicated horespower

Brake horsepower

Frictional horsepower

5 drops

3 drops

1 drop

1 drop in

1 drop in

per mm.

per ram.

per mm.

2 mm.

3 min.

88

88

88

88

88

2-28-10

2-28-10

2-28-10

3-2-10

3-2-10

215

215

215

215

215

125

125

125

125

125

44.68

44.98

46.15

45.15

44.80

39.4

39.4

39.4

39.4

39.4

5.2S

5 58

6.75

5.75

5.40

125
45.56
39.4
6.16

Buckeye, the other a noncondensing 7x
12-inch straight line. The Buckeye has a
piston valve, the straight line a gridiron
valve. Prony brakes are used for ab-
sorbing and measuring the power de-
veloped; the cylinders are tapped for in-
dicators, and the speed is controlled by
flywheel governors acting upon the valve
adjustment.

Tests were made upon each engine
running at approximately full load with
a steam pressure maintained constant at
125 pounds. The brake load was held
constant and readings of speed, steam
pressure, brake load, drops of oil per
minute and indicator cards were taken
at five-minute intervals for a half-hour
test. Six tests were made on two after-
noons, the engines not being used for
any other purpose in the meantime. On
the first day the tests were made using
respectively three drops, five drops and
one drop per minute through sight-feed
lubricators. The laboratory temperature
was about 88 degrees Fahrenheit and
while the amount of oil used in pints
was not measured, an idea of the quan-
tity is obtained when the number of
drops, make of lubricator and tempera-
ture of engine room are known. On the
second day, after finding from the pre-
vious tests that no difference in fric-
tional horsepower appeared, three tests
were made as before, using respectively
one drop in two minutes, one drop in
three minutes and no oil whatever.

Before the first test on each afternoon
the engine was wanned up at full load

to change. However true this may be,
it is believed that the general conclusion
from the six tests is not affected.

The results obtained show some varia-
tions in engine friction that are unex-
plainable except that the brake load was
not held as constant as it was supposed
to be held. Even considering these cases
of variation it is plain that the value for
frictional horsepower is practically con-
stant for all amounts of cylinder oil fed
to the engine.

On the first day the results may have
been soinewhat mixed because of feed-

the total engine friction appreciably,
therefore it is best to use as little oil
as possible, so long as the valves do not
groan and creak, .^nother natural con-
clusion is that too much oil is commonly
used on small high-speed engines.

It was customary to use three drops
of oil per minute on these engines here-
tofore. An Atlas 10xl6-inch engine
carrying the shop load has had its oil
supply reduced as a result of the above
tests and no effect upon its operation
has been noticed.

This matter must be left finally to the
judgment of the engineer, but it should
be remembered that sufficient oil is
enough ; any more is waste.

The foregoing tests were conducted by
seven senior students in mechanical en-
gineering under the direction of an in-
structor.

Preventing Gas Explosions in
Boiler Uptake

In a certain power plant the chief en-
gineer after much trouble and experi-
menting discovered a way to prevent the
gas explosions which occurred in the
smoke uptakes of his boilers and at the
same time to obtain better combustion
than he had been getting from the grade
of fuel used.

His method of firing the boilers is to
allow the furnace doors to remain open
about one inch at all times. No. 2 buck-
wheat and a 15 per cent, mixture of an-
thracite are used, the combination pro-
ducing an average of 18 per cent. ash.

The stack has a natural draft of Iji
inches. A forced-draft fan is used to
furnish air under the grates, the draft
being "s inch.

Aftei it was discovered that leaving
the doors of the furnace open prevented
tiiese gas explosions, the engineer came
to the following conclusion: Inasmuch

FKICTION TEST OF STR.\1GHT.LINE ENGINE

Quantity of oil

Date of test

Temperature of engine room,degrees F.

Speed of engine, r.p.m

Steam pressure, pounds gage . .

Indicated horsepower

Brake horsepower

Frictional horsepower

5 drops

3 drops

1 drop

1 drop in

1 drop in

per mm.
2-28-10

per mm.

per mm.

2 mm.

2-28-10

2-28-10

3-2-10

3-2-10

SS

88

88

88

88

270

270

270

272

272

125

125

125

125

125

22.12

22.44

21.39

21.76

21.93

19.53

19.53

19.53

19. 53

19.53

2.59

2 91

1.86

2 23

2.40

272

125

21.41

19 53

ISS

ing first three drops, then five and lastly
one drop of oil per minute, but the en-
gines were shut down after running 40
minutes on one drop of oil per minute
and were started the next day on one
drop in two minutes, and the feed de-
creased to no oil at all on the last test.
If any effect were to appear it ought to
show on the second day's run. but as
it did not, the general conclusion is that
the friction from the piston and valves
must be a small part of the total engine
friction; that the amount of oil fed to
the cylinder and valve does not affect

as the coal was fine and packed closely
together when thrown upon the grates,
it was natural that the firemen should
throw in too much coal at a firing and as a
consequence insufPcient air would be
forced up through the fuel which re-
sulted in incomplete combustion of the
gases. At times so much gas escaped
from the furnace without becoming
ignited that it would reach the uptake
before ignition took place, when, of
course, an explosion occurred. Admit-
ting an additional amount of air over
the grates prevented the trouble.

July 25, 1911

POWER

133

Automatic Step Bearing Pump

Most engineers are familiar with the
method of floating the rotating element
of a steam turbine, and know the con-
struction of the step bearing and the
method employed to maintain the oil
pressure.

At the power plant of the Lynn Gas
and Electric Company, Lynn, Mass.,
water is used in the step bearing, instead
of oil, a steady pressure being main-
tained, as is usual, by means of an ac-
cumulator. An auxiliary automatic punip-

':)' Pipe to Oage

1. Piping to Step Bearing

ing unit was installed in order to guard
against any possible accident to the tur-
bine. The unit is automatically cut into
operation when the pressure drops to
375 pounds, a pressure of 400 pounds
per square inch being the maximum.

Fig. 1 shows a partial view of the
Step bearing and the pipe connections.
The bottom -'a-inch pipe leads to the
accumulator and is fitted with a check
valve which remains open just so long
as the pressure in the step bearing re-
mains normal. The check valve in the
upper pipe, which leads to the auxiliary
pump, remains closed so long as the
water pressure in the accumulator con-
tinues normal. If there should be any
trouble in the accumulator, or the pipe
leading from it to the step bearing, the
check valve in pipe A will close, due to

Brush Contacts-^
on Accumulator i

To 550 Volt Mains
Fic. 3. Wiring Diagram of Alar
System

An auxiliary pump icliicli
IS electrieally controlled and
is automatically started and
stopped between predeter-
mined limits of pressure on
the step bearing.

a reduced pressure, and the check valve
in pipe B will open, due to a pressure
which is maintained by the auxiliary
pump, which is automatically started,
either by the accumulator dropping a
predetermined distance below normal of
about five inches, or to the reduced pres-
sure in the pilot pipe leading to the auto-
matic apparatus.

On the bottom of the accumulator
there is attached an arm to which is con-
nected an ordinary brushholder contain-
ing carbon brushes. Attached to a post
that extends from the basement ceiling
to the cement floor of the basement are
four contact blocks arranged as shown
in Fig. 2. The upper contacts are con-
nected by wires to an electric bell. The

circuit through the two upper contact
pieces, which causes a bell to ring in
the turbine room, thus calling the engi-
neer's attention to the fact that the ac-
cumulator is floating at a low level. If
the accumulator still continues to drop,
the circuit is closed through the two
lower contacts, causing a current to flow
through the coil D, Fig. 3, which closes
the switch F, and thus operates the oil
switch on the motor circuit.

Fig. 3 shows a diagrammatic view of
the controlling apparatus, and Fig. 4

Fig. 2. Accumulator Alarm System

shows a general view of it. The opera-
tion of this apparatus is as follows: The
pressure gage G is connected by the pilot
pipe with the step bearing of the tur-
bine. This pressure gage is fitted with

Fig. 4. General View of the Controlling Apparatus

lower contacts are connected with a
coil which closes the circuit through the
coil D, shown in Fig. 3. the operation of
which will be explained later. As the
accumulator drops below a predeter-
mined point the carbon contacts form a

a pointer and an adjustable contact fit-
ted to a brass ring on the dial of the
gage. The contact is made adjustable
in order that the point of contact be-
tween it and the finger may be regulated
at will.

134

In case an accident should happen to
the piping between the accumulator and
the step bearing, the pressure would be
reduced in both the pipe and in the pilot
pipe, which allows the gage finger to
move backward until it comes in con-
tact with the brass contact piece which
forms a circuit from the main feed line
H through the wire J and coil D. This
magnetizes the coil and draws the plunger
K up into it, thereby closing the switch E.

Referring to Fig. 3 again, it will be
seen that there is a low-resistance coil
between the two wires as shown. This
resistance is of such strength and the
plunger K is so delicately balanced that
once it is drawn up into the coil the
current passing through the shunt and
coil is just strong enough to hold it sus-
pended; the closing of the circuit through
the pressure gage is for the purpose of
supplying an extra amount of current
momentarily to the coil D.

When the switch £ is closed, a cur-
rent passes in the proper direction
through the solenoid coil of the oil switch
to draw the plunger up, closes the switch
and permits a 550-volt current to pass
through the circuit-breaker to the motor
of the pump.

The relay coil is in series with the re-
sistance coil and when the pointer
is in contact, it cuts out the resistance
and allows the current to draw the
plunger up into the coil.

The pump motor is of five horsepower
capacity, and is of the three-phase squir-
rel-cage type, and is geared to a Deane
three-plunger power pump.

POWER

was taken by means of a stop watch.
The temperature of the water was taken
so that the weight per cubic foot could
he found from a table. This discharge
in cubic feet per second is
w

'^ ~ TxTr

in which iv is the number of pounds of
water discharged into the tank, t is the
time in seconds for this water to flow-, and
W is the weight of this water per cubic
foot as taken from the table.

The velocity of the water in the pipe
in feet per second was calculated by
means of the formula

0 = av, or V = -
" a

in which a is the cross-sectional area of

the pipe in square feet. The loss of

Loss of Head in Pipes

By J. E. PocHE

The loss of head due to the resisting
friction of the interior surface of a pipe
is comparatively large, so that the dis-
charge is only a small percentage of that
due to the head. The friction factor for
three different small pipes of approxi-
mately the same size was obtained in a
test, and the results and method of per-
forming the experiment are here given.

The pipes tested were of wrought iron,
galvanized iron and brass, respectively.
They were laid horizontally in a straight
line so that no other losses except that
of friction could occur. The area of the
cross-section of each pipe was accurate-
ly ascertained by filling a known length
of the pipe and then measuring its cubic
contents. A differential mercury gage
was used to measure the loss of head
in each pipe between two points exactly
30 feet apart. A valve was placed at
each end of the pipes, so as to change
the difference oi' head between those two
points.

The discharge per second was ascer-
tained by making the water run into a
tank placed on a scale; and the time for
a convenient number of pounds to flow

1 1

'1' /

^/

\

ii

*

t

1

i/ i

r

y ^

;

^

/

/

i

J- i-

A /o

1 1 /

tt

1

^1

1 /

;

1

/I)

f

1

//

C

//i

:c

/

'i

^

' V~^

'

1

. ///

■- r

///

■ Iron Pip

1

0.6

/// 1

^-BrassPi

0.45

/ // 1

.1

JJL^

1 1

1

0,35

///

j 1

777

1

1

0.225

7/ "

Mr

018

/ ! 1

i i

Z i
Veic

3 3.5 44.5 5 6 7 89 10
, Feet per Second

July 25, 1911

for each of the three pipes. The water
was turned on, the gage being properly
connected up, and the valve at the top
of the gage was opened to allow all the
air to escape. The valves at the ends of
the pipe were manipulated so as to get
the greatest value for the difference of
head (Hi — H=), and the time for 400
pounds of water to flow was taken. A
running start was made every time; read-
ings of the gage were taken several
times at short intervals during the run.
The table shows the mean of these read-
ings. The value of H, — H. was then
reduced by steps to nearly zero, readings
being taken at each step.

Assuming the values obtained during
test No. 3 for the wrought-iron pipe and
substituting in the above formulas, we
get:

400

- MI' 119.4 X 62.21

; = 0.0538 CU.ft.

H,

/ =

per second
_ g _ 4_0 _ 4 X 0.0538 _
~a ~~Trd'- 3.14 X (0.088) =

8.85 jeei per second
H= = 12.6 (2.57 — 1.855) = 9 feet
2 d' gh' _ 2 X 0.088 X 32.2 X 9

v-l

Chart SHO^x'lNG Loss of Head

head in friction is proportional to the
length of the pipe, increasing with the
roughness of the interior surface and de-
creasing as the diameter of the pipe in-
creases; it increases nearly as the square
of the velocity and it is independent of
the pressure of the water. Therefore
we can write the formula

in which h' is the loss of head in feet, /
is the length of the pipe — 30 feet in this
case — d' is the diameter of the pipe in

feet, and — is the velocitv head due to
2g

the mean velocity of flow. As all these
values can be measured except the coeffi-
cient of friction f, we solve for / and get
,2d'g}i
'— v-l
The values shown in the accompany-
ing table were obtained in the same way

(8.85)= X 30
= 0.0217

It is seen from the table that the values
for / increase in nearly every case as the
velocity decreases, as would be expected.
It is also observed that the loss of head
is greatest for the galvanized pipe and
least for the brass pipe.

If a curve is plotted on logarithmic
cross-section paper between the loss of
head in feet of water and the velocity
in feet per second for the values found
for the three pipes, we will get three
straight-line curves as shown. The value
of C, a constant for each pipe, in the
equation

can be found directly by prolonging each
curve until it crosses the axis of coordi-
nates. It remains now to find the value
of n in the above formula.

When f = 1, log. v = 0 and log. C =
log. Hf, or C = Hf, as can be seen from
the curves.

log. Hf = n log. V -+- log. C
For the wrought-iron pipe, C = 0.15.
Taking v = 4, then Hf = 2.05 and
log. 2.05 = n log. 4 + log. 0.15

0.313 = n X 0.603 + (9.177 — 10)
whence,

0.313
For the galvanized-iron pipe C = 0.225.
Taking i' = 5, then Hf = 4.75 and
log. 4.75 = n log. 5 -f log. 0.225
0.677 = n X 0.699 -f (9.352 — 10)
whence,

I. l2^

July 25, 1911

POWER

135

For the brass pipe C = 0.18. Taking v
= 8, then Hf = 7.15 and

log. 7.15 = n log. 8 + log. 0.18
0.855 = n X 0.904 -f (9.256 — 10)
whence,

« =1

0.904

From these calculations it is seen that
the value of n is very nearly 2, which
proves the statement made above to the
effect that the loss of head increases
"nearly" as the square of the velocity.
Other values can be assumed for r and
the corresponding values of Hf taken
from the curve and thus other values

Fuller's

Earth as an
Filter

Oil

"The Production of Fuller's Earth,"
by Jefferson Middleton, of the United
States Geological Survey, has just been
published as an advance chapter from
"Mineral Resources of the United States,
1910."

The fuller's earth resources of the
United States, says Mr. Middleton, have
attracted considerable attention for sev-
eral years because of the increasing de-
mand for this material for use as a clari-
fying agent for mineral and vegetable
oils. The original use from w^hich it

I.O.S.S OF HE,4D IX PIPES

^

_

t.^

11^
Si

a

Is

En"--

3'^

IE

h-^ i:

H,

Ft. Hg.

Difl.

oa^""

(-^

■'

Kl. kg.

H, — H,

^■X^

Wrovght-irox Pipe

I

91 .4

0 . 070.>

11.59

0.0212

2.855

1.610

1.195

15.05

Temp, of water = 75"

2

107.4

0 . 0599

9.85

0.0215

2.045

1.770

0.875

11.01

F. Diam. of pipe =

»

110.4

0.0538

8.85

0.0217

2.570

1.855

0.715

9.00

0.088 ft. Area of

4

135.2

0.0475

7.82

0.0222

2.405

1.925

0.570

7.18

pipe = 0.00608 sq.ft.
Length of pipe = 30 ft.

ft

1.J3.2

0.0419

6.89

0.0225

2.437

1.990

0.447

5.64

6

160.8

0.0378

6.24

0.0221

2.308

2.030

0.368

4.14

29d

7

221.4

0 0200

4.77

0.0236

2.328

2.102

0 . 226

2.,S4

=0.189

8

307 . S

(1.0161

2 65

0 . 0255

2.253

2.178

0.075

0.945

I

i.vAxizEo-iRox Pipe

1

103 0

0.0024

9.02

0.0347

2.920

1.51

1.410

.7,75

Temp, of water = 75°

2

108.8

0.0590

0.39

0 . 0356

2 . 8.55

1..56

1 . 295

16.30

I. Diara. of pipe =

3

117.0

0.0549

8.74

0.0362

2.780

1.64

1.140

14.36

0.0895 ft. Area of

4

125.0

0.0514

8.45

0.0321

2.685

1.74

0 . 945

11.90

pipe = 0.00629 sq.ft.
l/?ngthof pipe = .30 ft.

h

141 0

0.04.54

7.23

0.0349

2.605

1.85

0 . 7.55

9.50

fl

174.2

0.0369

5.87

0 . 0372

2.475

1.95

0 . 525

6.66

29d

7

210 0

0.0304

4.84

0.0346

2.385

2.05

0.335

4.22

= 0.102

8

372 0

0.0172

2.74

0 . 03H8

2 . 280

2.16

0 120

1.51

I

I

92 4

0.0695

11.29

0.0202

2.750

1.675

1.075

13.55

Temp, of walir-75°
F. Diara. of pipe =

2

106.8

0.0601

9.76

0.0206

2.620

1.800

0.820

10.34

a

123.4

0.0.520

8.44

0.0222

2.540

1.880

0.660

8.31

0.0SS5 ft. Area of

4

135.0

0.0476

7.73

0.0217

2 485

1 . 945

0 . 540

6.80

pipe = 0.00615 .sq.fl.

ft

145 6

0.0441

7.16

0 0217

2 . 445

1.980

0.465

5.85

■.eliElhof pjpr = 30fl.

6

168.8

0 . 0382

6 21

0.0229

2.400

2.035

0 . 365

4.60

29</

7

228.0

0.0281

4 . 56

0.0242

2 . 320

2.110

0.210

2.64

= 0 10

H

420.0

0.0152

2 4S

0.0272

2 255

2. 185

0,070

OSS

/

for n can be found. But in each case
they will be very close to those calculated
above.

The majority of boiler explosions oc-
cur not while the boiler Is in regular
service but while it is being started up,
particularly if the boiler is being limbered
up after a period of idleness. One point
itiay be noted. When a boiler has been
standing cold for some time the steam
gage is more likely to become stuck
than at other times, and the spring may
not throw the needle accurately. To
guard against the danger which comes
where the needle sticks, it is advised
that whenever a plant has but one boiler
that boiler should have two steam gages.
Then if one happens to stick the chances
are very small indeed that the other will
Rgister wrong also.

derives its name, the fulling of cloth, is
now of minor importance.

For a great many years fuller's earth,
was imported from England, the only
known source of supply, but in 1893 it
was by accident discovered in this coun-
try. At Quincy, Fla., an effort was made,
without success, to burn brick on the
property of the Ow! Cigar Company. An
Alsatian cigarmaker employed by the
company called attention to the close re-
semblance of this clay to the German ful-
ler's earth. As a result of this suggestion,
the clay was tested and found to be ful-
ler's earlh, and the industry was de-
veloped. This discovery caused consider-
able excitement, and supposed deposits
of fuller's earth were reported from a
number of States. The material in most
of these deposits, however, was found to
he of no value as fuller's earth. Since

the discovery, Florida had been the lead-
ing State in production. During the early
history of the industry fuller's earth was
produced in only two or three States.
In 1897 to 1899 it was reported from
Florida, Colorado and New York, with a
very small production from Utah; in
1901 Arkansas was added to the list.
From 1904 to 1907 Arkansas was the
second largest producer. Shortly after
its discovery in Florida, fuller's earth
was found in Georgia, but Georgia did
not appear as ,t producer until 1907,
when it was the third largest produc-
ing State; it ranked second in 1909 and
1910. In 1904 Alabama and Massa-
chusetts reported production, in 1907
South Carolina and Texas first appeared,
and in 1909 California entered the list.

The principal use of fuller's earth in
this country is in bleaching clarifying,
or filtering of fats, greases and oils. The
common practice w-ith mineral oils is to
dry the earth carefully after it has been
finely ground, and run it into long cylin-
ders, through which tiie crude black min-
eral oils are allowed to percolate very
slowly. As a result, the oil that first
comes out is perfectly water white and
much thinner than that which follows.
The oil is allowed to continue percolating
through the earth until the color reaches
a certain maximum shade. Then the
fuller's earth itself is clarified by a
steaming process and used over again.
With vegetable oils, however, the pro-
cess is radically different. The oil is
heated beyond the boiling point of water
in large tanks, from 5 to 10 per cent, of
its weight of fulUr's earth is added, and
the mixture is vigorously stirred and then
filtered off through bag filters. The color-
ing matter remains with the earth, the
filtered oil being of a very pale straw
color. American fuller's earths are bet-
ter adapted than the English earths for
use on mineral oils, but the English
earths are superior for the treatment of
fats and vegetable oils. In clarifying
vegetable and animal fats with Ameri-
can earlhs a more or less disagreeable
taste is left — just why has never been
determined.

To show the growth of the American
industry it is only necessary to state that
from 6900 tons in '895 the production
increased to 33,186 tons in 1909. This
was the maximum, the output for 1910
being 664 tons less. Florida was the
leading producing State in 1910, furnish-
ing 57.38 per cent, of the total output,
or 18,832 short tons. The other produc-
ing States, named in the orJrr of their
rank in output and value in 1910, were
Georgia, Arkansas, Texas, California,
Massnchusetts, South Carolina and Colo-
rado.

Those of our readers who are inter-
ested in the subject may obtain a copy
of Mr. MIddlclon's report upon appli-
cation to the director of the Geological
Survey at Washington. D. C.

136

POWER

July 25, 1911

Ventilation of Turbine
Generators

It is well known that the output of the
type of alternating-current generator
used with steam turbines is limited en-
tirely by the heating of its inner parts;
the machines are so small for their out-
put (by reason of their high rate of
speed) that ventilation of them is diffi-
cult. Forced ventilation by means of
external fans driving air into and through
ducts in the machine has been employed
in many cases; in others, the fans for
forcing the air through the machine have
been attached to the ends of the rotating
member. All of these expedients have
extended the limit of safe full load, as
compared with natural ventilation.

A method w-hich comes within the last
mentioned general class but which ap-
pears to be exceptionally efficient has
been devised by Charles F. Baker, of
Newton, Mass., and is illustrated here-
with. Mr. Baker uses a series of pecul-

fo the buckets of an impulse water-
wheel, as a glance at Fig. 2 will show;
their curve, however, is much flatter and
the concavity much shallower. Owing
to their shape and the extension of the
inner lips beyond the inner faces of the
disks, the fan vanes combine the effects
of both the turbine and the centrifugal
types of blower; the portions of the
vanes on the outside of the disks act to
force the air in the axial direction and
after it gets inside the disks, the vane
lips act like the blades of a centrifugal
fan and force part of the air outward

windings. Both axial and radial ducts
are provided in the rotor core, so that
the air which is blown into the core
axially escapes radially, passing out
finally through ducts in the stater core.
Mr. Baker informs us that a 2000-
kilowatt generator equipped with this
type of ventilating fan carried a load of
3000 kilowatts with a maximum tempera-
ture rise of 38 degrees. Centigrade, which
was 6 degrees less than its normal tem-
perature rise with the normal load of
2000 kilowatts. Fig. 3 shows the field
magnet of this generator with the Baker

Fic. 2. One of the Vanes

fan vanes and disks attached; it illus-
trates very effectively the relatively in-
significant space occupied by the ven-
tilating device.

LETTERS

Parallel Operation of Alterna-
tors Driven by Waterwheels

In the issue of June 27, H. T. Dean
asks about the parallel operation of al-
ternators driven by waterwheels in sep-

flg. 1. longitlininal section of generator equipped with baker
Vkntilatinc Vanes

Fig. 3. Rotor Equipped with Vanes

iarly shaped fan blades set into open- radiallv through the overhanging stator arate stations. The question of good

ings in two disks which are mounted on
the shaft, one at each end of the rotor,
as represented in Fig. 1. These fan
blades or vanes bear a slight resemblance

windings. The disks are made as large
as possible, just clearing the support-
ing rings which are set within the over-
hanging portions of the stator (armature)

operation under such conditions depends
very largely upon the generator and the
wheel. Generators should be purchased
which have inherently good character-

July 25, 1911

istics for parallel operation, and too close
regulation should not be attempted. There
are built generators having what is known
as damping windings, which are very
well adapted for work of this character,
owing to the fact that these windings
to a large extent prevent hunting. With
generators of this kind or generators
having sufficient inductance to hold each
other together, there should be no diffi-
culty in their being installed at the dif-
ferent locations, provided the governors
are of moderate sensitiveness and not
allowed to overrun, and allowing one
of the generators to govern for the three,
with its governor set rather more sen-
sitively than the other two.

As it is desired that the small units
should operate at full capacity constantly,
it would be good policy to have the
waterwheels of these generators of a
capacity which would cause them to slow
down when the load reached the maxi-
mum point desired, thus automatically
throwing the load upon the larger gen-
erator. With both of the smaller wheels
arranged in this way these wheels would
carry their maximum load continuously;
any excess load would be automatically
thrown upon the larger machine.

The instruments required at each sta-
tion in order to operate these units in
parallel would be a voltmeter to indicate
the voltage on the phases, ammeters to
indicate the load currents and a syn-
chronizing equipment for use in throw-
ing them on the line. A power-factor
indicator might also be installed to good
advantage.

In putting the machines upon the line,
in case one is operating, the second ma-
chine should be started up, brought up
i to speed and voltage, then the machines
gradually brought into synchronism. To
do this will require that the governors
be provided with a loading and unload-
ing device, by means of which the speed
of the machine can be adjusted to a
moderate extent. When the machines are
exactly in synchronism and the voltages
of the machine and of the line are the
same, the switch is closed, throwing
the incoming machine on the line. In
order to make this machine pick up its
load, the speed is increased more or
less, depending upon the amount of load
required for the machine to take, by
means of the speed-adjusting device on
the governor, as alternators do not divide
their load in accordance with the volt-
age but in accordance with the power
delivered to them by the prime mover, in
this case the waterwheel.

In order to take a machine off the
line, the speed of the waterwheel is
decreased slightly by means of the speed-
adiusting device on the governor until
the machine drops its load, as shown by
•he ammeter. When the load has reached
zero or approximately zero, the line
switch is opened and the machine dis-
connected from the line. The wheel can

POWER

then be shut down and the field circuit
opened, after the resistance has all been
cut in.

Henry D. Jackson.
Boston, Mass.

Under the conditions described by Mr.
Dean, parallel operation can be satis-
factorily accomplished by running the
small units without governors, the only
disadvantage being that if the load
should ail be taken off suddenly by
feeder fuses blowing or some other
cause, the two smaller machines would
run away unless the large wheel dragged
hard enough to hold them or unless there
was an attendant at hand to shut the
gate. Except for this objection, the
scheme is entirely practicable; I have
operated machines under the same con-
ditions and had no trouble.

For instruments, in addition to the syn-
chronizing lamps with their necessary
connections, on the switchboard for the
200-kilowatt machine I would add a
power-factor meter, a frequency meter
and an indicating wattmeter. I should
install at least one feeder panel hav-
ing the necessary switches and cutouts,
also an indicating wattmeter to show the
total load; then, if any accident should
happen to the large unit, part of the load
could be carried with the other machines
if it was steady enough, as a lighting
load or some motor loads might be.

On the boards for the smaller ma-
chines I would provide an alternating-
current voltmeter, a frequency meter and
an indicating wattmeter. It might also
be desirable to add field ammeters but
they are not necessary on such a small
installation, as readings can be taken
from time to time with portable instru-
ments. I prefer indicating wattmeters
to ammeters because of the probable
flow of wattless cross-currents which
would make it hard to determine whether
the machine was loaded up or not.

To throw one of the small machines
on the line, both field resistances should
be reduced so that when the speed is
near normal the voltage will build up and
cause the frequency meter to indicate.
This speed should be attained by open-
ing the waterwheel gate as much as is
necessary; after doing this a few times,
the operator will know just about how
much to open it. Assuming that the fre-
quency is 60 cycles, when the meter in-
dicates about that and the proper voltage
is attained, the synchronizing plug should
be put in and if the lamp goes on and
off very rapidly, then the gate may be
adjusted one way or the other to find
whether the machine is above or below
the speed of the other generators; if
above, if should be closed a very little
so that the fluctuations of the lamp will
be very slow; then, at the proper instant,
just as the lamp shows synchronism, the
main switch should be thrown in. after
which the gale should be opened wide
and the voltage raised to compensate

137

for the drop due to the load, which will
be steady on these machines, all fluctua-
tions being taken care of by the large
unit.

To throw one of the units off the line,
the field resistance should be partly cut
in and the wheel gate slowly closed
until the wattmeter shows no load, when
the main switch may be pulled and the
wheel shut down entirely. At the same
time the operators at the other stations
should watch their voltmeters for a drop
in voltage and cut out field resistance
to compensate for it.

Should the load become loo light to
run the smaller machines at their full
capacity and yet should it not be de-
sirable to cut them out, the gates could
be partly closed until they carry any
portion desired. After a few trials it
will be very easy to manipulate the three
units under all conditions in reason.

G. H. Kimball.

East Dedham. Mass.

Referring to Mr. Dean's inquiry as to
whether or not it would be desirable to
place governors on two small water-
wheels located at different points and
driving alternators to be paralleled with
a 200-kiIowatt machine now in opera-
tion, I should say that it is not absolutely
necessary but will be most desirable,
for it must be remembered that the
dividing of loads on alternators in paral-
lel is a question of power only, and the
load cannot be shifted from one ma-
chine to the other (although many engi-
neers insist that it can) without a change
in speed of the prime mover or, more
strictly speaking, a tendency thereto.

Therefore, if a unit driven by a gov-
erned waterwheel be paralleled with a unit
operating without a governor, there ex-
ists a condition where one unit (with
the governor) has a speed regulation
of, say, about 4 per cent, from full load
to no load, and the other unit (without
a governor) has a speed regulation of
practically 100 per cent, from full load
to no load; for, if the water supply is
not regulated the unit will naturally
speed up as the load is taken off. In a
way, however, this would accomplish one
point which Mr. Dean desires to cover,
namely, for the two smaller units to
work at maximum capacity constantly.
In paralleling units with and without
governors, however, an unsatisfactory
condition will exist, as it must follow that
alternators driven by prime movers w':h
different regulation will cause cross-cur-
rents to flow between the machines and
a poor power factor, necessitating con-
stant hand regulation of field strength,
not to mention the constant danger of
the units without governors running
away.

I think that the best method of operat-
ing the units in question would be to
have governors on all the waterwheels;
it will be advisable to provide each gen-
erator with one voltmeter, an ammeter

138

POWER

July 25, 1911

for each phase, an indicating kilowatt-
meter, a synchronizer and a power-factor
indicator. The method of paralleling
should be as follows:

The incoming machine should be
brought up to synchronism, the volt-
age regulated to correspond with that
of the line, and when the machines are
in step the incoming unit thrown in, at
which moment the ammeters and kilo-
wattmeters will probably indicate zero.
The governor of the incoming unit should
then be adjusted so as to give that unit
a tendency to speed up and take any
desired portion of the load. In taking a
generator off the line, either the governor
can be adjusted so that its generator
carries practically no load, when it may
be taken off the line, or, if it is unde-
sirable to touch the governor after it
is once set. the water supply can be
otherwise throttled and the generator
taken off the line when its load has
fallen to about zero; when again start-
ing up, it can be brought up to speed
under the hand gate wheel and. after
paralleling, the gate opened, allowing
the speed to be regulated by the gov-
ernor.

P. C. OSCANYAN.

Newark, N. J.

In order to operate three waterwheel
alternators in parallel under the condi-
tions described by Mr. Dean, I think
that it will be necessary to have no addi-
tional instruments for the 200-kilowatt
generator except, of course, a synchroniz-
ing outfit; but a power-factor indicator
and a frequency indicator would be
very useful when running in parallel
with the other generators. The switch-
board of the smaller alternators should
have the same instruments as that of
the large one.

The method of cutting in one of the
smaller units would be to bring the gen-
erator up to speed by hand regulation
of the waterwheel gate and to synchronize
as usual; then open the gates wide and
let the generator carry all the load that
the wheel can pull, leaving regulation
to the large machine.

No governor is necessary on either
of the small wheels, but if a governor
is used it should be set, after the ma-
chines are paralleled, for a slightly
higher speed than is desired in order
that it will keep the gate wide open and
act as a speed limit if the generator
should lose its load.

In cutting out one of the smaller gen-
erators, simply close the wheel gates
until the generator load is reduced to
nothing and then cut it out.

When running these machines in paral-
lel it will be necessary to adjust the
field current so that the power factor
of each generator will be the best ob-
tainable under the conditions of load;
if the larger machine has spare capacity
and the smaller ones are loaded, by
strengthening the field of the former and

weakening those of the latter, the kilo-
volt-amperes of the smaller machines
can be reduced.

E. T. Reed.
Woonsocket. R. I.

Considering .Mr. Dean's problem of op-
erating separately located hydraulic tur-
bine-driven generators in parallel, I
should say that very much depends on
the nature of the load. If the load is
mostly lamps, with only a few -small
motors, and the load changes are gradual,
the system should work well with a gov-
ernor on the large machine only. On
the other hand, if there are large motors
on the line which are frequently thrown
on and off, they will be liable to cause
hunting of the small generators which
might cause either one or both of them
to fall out of step or to run as syn-
chronous motors, thus adding to the load
on the large generator. This could be
overcome, in part, by supplying both
smaller waterwheels with governors set
so as to be rather sluggish in their ac-
tion. It would be better in either case
to have the exciter of the large gen-
erator separately driven, preferably by a
small steam or gas engine.

On all three-phase systems the load
should be as evenly balanced as pos-
sible between the phases and the three
ammeters on the main switchboard will
tell when this is true and also be of use
when further balancing is necessary.

As the two small generators are to be
operated at full load when on the line,
all of the regulating should be done at
the main power house.

The instruments needed on each of
the switchboards for the small generators
would be one wattmeter, one ammeter
on the generator side of the main switch,
one synchronism indicator or synchroniz-
ing lamps, one oil-insulated main switch,
one field-circuit switch, one rheostat and
one voltmeter with plugs and sockets by
means of which the voltage on any phase
on the line can be read when the small
generator is not running. The attendant
should also be able to use this voltmeter
to read the voltage on the small gen-
erator when the main switch is open.
1 do not think it would be necessary to
have an ammeter and voltmeter on the
exciting circuit of either of the small
generators and an indicating wattmeter
would be the only new instrument re-
quired on the 200-kilowatt switchboard.

To put one of the small generators on
the line, if its turbine has no governor,
first determine by experiment where the
handwheel on the rheostat has to be set
to give a voltage about 1 per cent, above
that on the line with the generator run-
ning at synchronous speed. To get this,
the gate on the turbine should be only
partly open. Then put in the synchron-
ism indicator plugs and, when the two
generators are in step, close the main
switch. The voltage on the small gen-
erator being a little high, it will immedi-

ately take part of the load; therefore,
the gate on the turbine should be opened
a little more. Then by gradually cutting
out the resistance in the field circuit and
opening the gate of the turbine the gen-
erator can be made to take full load.

To cut out a generator, reverse the
order by slowly cutting in resistance in
the field circuit and at the same time
closing the gate of the turbine until the
wattmeter shows no load. The main
switch may then be opened and the unit
shut down. It may take some practice
to do this without causing a fluctuation
in voltage but with ordinar\' care one
should have no trouble. The only dif-
ference there would be if the small units
were supplied with governors would be
that it would not be necessary to regu-
late the gate of the turbine.

Leonard H. Holtzapple.

Winona, Mich.

Referring to Mr. Dean's inquiry in the
June 27 issue of Power, I see no rea-
son why the machines could not be run
as he desires. There should be a gov-
ernor on each of the waterwheels; when
alternators operate in parallel, each will
carry an amount of the load proportion-
ate to the pow-er received from its prime
mover and that power must be deter-
mined by a governor. A panel switch-
board will be needed at each station, as
well as lightning arresters. The boards
should be equipped with the usual am-
meters and switches for the generator
and the exciter, with voltmeters for both
machines, rheostats and circuit-breakers
(or fuses) and switchboard transformers
and synchronizing lamps.

Two methods of connecting synchroniz-
ing lamps are used, the one for "syn-
chronizing dark" and the other for "syn-
chronizing bright." With the first method,
the synchronizing lamps are dark when
the incoming machine is in phase with
the busbar current; with the latter, the
lamps burn at maximum brilliancy when
synchronism exists. Whichever method
is used, the speed of the incoming al-
ternator should be adjusted until the
fluctuations of the synchronizing lamps
are very slow; this will enable the at-
tendant to close the generator switch
with more certainty at or near the moment
of synchronism. After the incoming ma-
chine has been synchronized and thrown
on the line, its waterwheel gate can be
opened gradually until it is wide open
and the governor is handling the wheel.
If this is done and the field excitation
is adjusted carefully by means of the
rheostat, the voltage of the line will not
be disturbed by cutting in the machine.

Automatically operated oil switches
are commonly used, for sx'nchronizing
and cutting in, instead of the main switch
in many large power stations, and they
save much time both in putting machine?
in parallel and in shutting them down.

R. A. CULTRA.

Cambridge, Mass.

July 25. 1911

POWER

139

Equipment of the Gas Power
Yacht "Progress"

For some time past the possibility of
using internal-combustion engines for
ship propulsion has been attracting the
attention of marine engineers in all parts
of the world. The simplest solution of
the problem consists, no doubt, in adopt-
ing oil as the fuel to be used, since this
gets rid at one stroke of all difficulties
connected with the producer; but though
this is the simplest method of adapting
the internal-combustion engine to marine
purposes, it cannot be considered as gen-
erally applicable, because the cost of oil
fuel in many parts of the world is quite
prohibitive. It seems certain, therefore,
that if the ship of the future is to be
fitted with internal-combustion engines,
the plant must be one capable of using

AirCompreaor
Main Efhausf Oil
Pipes

and have had to be overcome by a pro-
cess of trial and error.

The engine is a double-acting pro-
ducer gas engine, with three cylinders
8;4 inches in diameter by 9 inches stroke,
driving the propeller direct without the
interposition of any form of gearing. It
operates on the two-stroke cycle and de-
velops 100 indicated horsepower when
running at 200 revolutions per minute.

what cramped in view ot the fact that
the installation to be tested was an ex-
perimental one, with which it may al-
ways safely be assumed that certain
modifications in details will be proved by
experience to be necessary or advisable.
On the other hand, the producer, though
large enough for an engine of more than
double the output, required much less
space than was occupied by the original
boiler.

The arrangement of the plant as finally
fitted on board is well shown in Figs. 1
to 6. The producer and the scrubber
stand in the stokehold, the air reservoir
used in reversing the engines being fitted
in on the port side of the scrubber,
while the exhaust-silencer is on the star-
board side, as shown in Figs. 2, 5 and 6.
This exhaust-silencer, it should be added,
has proved very efBcient, the noise, with

"Lockers c ^-

water Tank ^'"'^Loch.r CnJar,,,^ P^mp

Fig. 2

Fics. I TO 6. Secttons of the Gas Power Yacht "Progress"

gas derived from ordinary coal. This
being so, the marine gas-power plant
herein described is of great interest.

The original designs were got out about
three years ago, and appeared to give
such promise of success that a syndi-
cate was formed to build an engine and
install it in a small boat, with a view to
having the efficiency of the system tested
and its weak points eliminated by the
light of actual experience. In essentials
the system remains the same as origi-
nally designed, but, as is practically al-
I ways the case with a departure from es-
I tablished practice, various difficulties con-
I necled with the subsidiary details arose

The gas is supplied by a suction pro-
ducer which has been worked with anthra-
cite, with coke, and with coalite; the lat-
ter is said to have proved very satisfac-
tory, there being less clinker formed than
with coke.

The engine, with its producer and
auxiliaries, was fitted on board an old
torpedo boat originally driven by steam
engines. The original propeller and
propeller shaft was retained, hut it was
necessary to rebore the stern post, as
the center of the gas-engine crank shaft
was at a higher level than that of the
original engines. The space available
around the engine was naturally some-

thc engines running, being hardly greater
than with steam.

The main engine is illustrated in Figs.
7 to 10. As shown in Fig. 9, provision
was made for water cooling the piston,
but this has proved unnecessary. Each
cylinder, as may be seen, is constructed
somewhat on the well known Korling
lines, the exhaust taking place through
ports provided around the middle of the
cylinder, these ports being uncovered
by the piston as it approaches the end
of each stroke. A large three-cylinder
air pump, the piston displacement of
which is from two or three times as
great as the displacement of the pis-

140

POWER

July 25, 19U

tons in the working cylinders, is ar-
ranged as indicated in Fig. 9, occupying
much the same place as the air and cir-
culating pumps in a common type of
marine engine. The linkage (best seen
in Fig. 10) by which the pump is driven
is arranged so that the pump piston is

air) is sucked in from the producer. As
a consequence, during the first portion
of the air-pump stroke, when the piston
is between these ports and the air ports
at the end of the cylinder, pure air
alone can be sucked in. The supply pipes
for this air are at A and B in Fig. 9.

the working piston uncovers the exhaust
ports in the main cylinder, so that the
pressure there has been reduced to that
of the atmosphere. Hence, on the air-
pump piston beginning its return stroke,
the valve D is lifted and the pure air
which has collected at the top of the

Fig. 10

Fir.s. 7 TO 10. Thh 100 Horsepower Engine of the Yacht "Progress"

in quadrature with the main piston; that
is, the air-pump piston is at midstroke
when the main piston is at the end of its
stroke. Each cylinder of the air pump
has also ports provided at the midpoint
of its stroke, and it is through these
ports that the gas supply (mixed with

Upon the descent of the air-pump pis-
ton, pure air enters at A, partially filling
the long connecting pipe C. Later on, the
air-pump piston uncovers the ports in
its cylinder, and during the remainder of
its stroke mixture is drawn in. .Just after
this piston reaches the end of its stroke,

pipe C enters the cylinder and washes
out the spent gases through the still
open exhaust ports. The continued up-
ward motion of the air-pump piston
forces into the working cylinder a fur-
ther supply from the pipe C. but this
supply now contains gas, and the charge

luly 25. 1911

POWER

141

of mixture in the cylinder is compressed
and fired in the usual way.

The Lodge electric ignition system is
used and it has been found by actual
experiment that with this a good spark
•will pass even when the plug is covered
with a deposit of heavy oil. Ignition
current is supplied by an accumulator

Diaphragm

11. Regulator of Steam Supply to
Producer

which is kept charged by a small dynamo
driven from the main engine.

The lower end of the working cylinder
is connected to the other end of the air-
pump cylinder and is scavenged and
charged in exactly the same way as is
the upper end. When the engine is to
be reversed, the connections between the
ends of the working cylinder and the
ends of the air pump are changed over
by the four-way valve shown at £, Fig.
9. By rotating this valve through a
right angle the top of the working cylin-
der becomes connected to the bottom of
the air pump, and vice versa.

An additional air pump, shown at F,
Fig. 9, furnishes the supply of com-
pressed air for starting and reversing the
engine. The air supply for this pur-
pose is led to the engine by a pipe which
passes along the back of the cylinders
as indicated at G, Fig. 9. Branches con-
nect this pipe with a couple of balanced
valves normally held closed by springs
and opened by cams on a cam shaft
driven by spiral gearing from the main
•baft, as shown in Fig. 10. These cams

do not "positively" open the valves, but
do so through the intermediary' of buffer
springs. Hence, once the engine starts
firing and the pressure consequently
rises in the cylinder, the cams are no
longer able to open the valves, but mere-
ly compress the springs, so that the air
supply is automatically shut off as soon
as it is no longer required. In starting
or reversing the engine the supply of
compressed air is required for one or two
revolutions at most. This feature af-
fords great economy in the consumption
of compressed air, and the engines have
frequently been manoeuvered to a far
greater extent than would ever be re-
quired in practice, with but the small
auxiliary compressor running and with-
out material loss of pressure in the reser-
voir. In rough weather, if the supply of
air is left on, it will prevent the acci-
dental stoppage of the engine when it has
been throttled down to prevent racing
and the propeller is suddenly reimmersed.
The range of speed over which the en-
gine will run satisfactorily is from 40
up to 210 revolutions per minute.

The reverse lever of the engine is
shown in its neutral position at K, in
Fig. 7. It will be seen that there are
two notches on each side of the central
notch. Of each of these pairs of notches,
that nearest the neutral notch corre-
sponds to the running position of the
engine, and the outermost to the starting
position. With the lever in the starting
position the cam shaft controlling the
air supply is shifted so as to operate the
air valves in correct sequence for the
desired direction of rotation, and at the
same time the spark is retarded in each
cylinder and the four-way gas valves E
are simultaneously moved so as to con-
nect the appropriate end of the air cyl-
inder to the top of the main cylinder.
As soon as the engine starts firing, the
lever is moved back to its running posi-
tion, an operation which moves the cam
shaft clear of its followers. As instanc-
ing the handiness of the engine, it may
be stated that, in coming out of dock
on one occasion twenty-six different
movements were made in the course of
21 minutes. The time taken to reverse
has been found to be from three to four
seconds after the order is given.

The main difficulty experienced in se-
curing easy manipulation of the engines
was due to the producer. In land prac-
tice a suction-gas plant, once started,
runs commonly without violent fluctua-
tions in the output demanded. With a
marine engine, when coming in or out
of port, the conditions are ver>' different,
and it was found that special steps must
be taken to maintain the quality of the
gas and tha strength of the mixture,
whatever the temporary draft on the pro-
ducer. For producers furnishing gas to
a land engine the supply of water or of
steam can be conveniently adjusted by
hand, but experience showed that an au-

tomatic control was desirable for the sup-
ply to a marine producer.

To provide this control, the apparatus
illustrated in Fig. 1 1 was devised. The
steam supply (at atmospheric pressure)
is obtained from a small separately fired
boiler. The steam is delivered through a
rose sprayer fixed, as shown, at the top
of the air pipe leading beneath the grate
of the producer. Lower down in this
pipe a coil of tubing is fixed, which is
charged with pure methyl alcohol. The
top of this coil is connected to a pipe
leading to a chamber below a flexible
diaphragm, which chamber is filled with
heavy oil. A series of magnifying levers
transfer any motion of the flexible
diaphragm to a balanced valve which
controls the supply of steam to the
sprayer. At full speed this valve is
fully open and a full supply of air and
steam is drawn through the draft pipe
into the producer. When the speed of
the engine is suddenly reduced, the vac-
uum in the producer falls off and there
is less suction in the draft pipe. There-

Fif.. 12. Mixture Controller

fore less air is drawn in, and the coil
containing the methyl alcohol Is raised
in temperature by the excessive supply
of steam. As a result the vapor pres-
sure inside this coll is raised and the
increased pressure, acting on the flex-
ible diaphragm, moves the latter, clos-
ing the steam valve more or less. When
the speed of the engine is increased,
after having been reduced, a larger quan-

iL

142

POWER

July 25, 1911

tity of air is sucked into the draft pipe;
this cools down the coil, lowering the
pressure within it, and the steam valve
is then forced open by the spring above
it.

To maintain automatically the proper
relative proportions of gas and air in
the charge supplied to the engine, the
device illustrated in Fig. 12 is employed.

through slots in the air piston, and by
rotating the latter, the relative propor-
tions of air and gas can be adjusted.
This adjustment is made by turning the
mixture handle, shown at the top in
Fig. 12. The position of this having been
once adjusted to suit the quality of gas
being used, the "carbureter" automatical-
ly maintains the proper proportion of gas

TABLE OF RESULTS OBTAINED IX TESTS MADE BY E. A. ALLCUT

Trial

Duration, hours

Coal supply, pounds

Coal supply, bounds per hour

Heat value of coal. B.t.u. per pound .

Heat per hour in coal supplied, B.t.u. . . 213,000

Moisture, per cent, b.v weight 3.97

Ash, per cent, by weight 3.41

Air supply at 32° F. and 14.7 pounds per

square inch, cubic feet per hour

Temperature of air 56 . 4

Air, pounds per hour 64 . 1

Nitrogen, pounds per hour. 49.3

Oxygen, pounds per hour 14. S

Au' per pound coal, pounds

Water in air. pounds per hour. . .
Water feed, pounds per hour. . . .

Temperature of water

Total water to fuel bed, pounds per hour

Water per pound coal

Weight water per hour

Weight air per hour
Weight oxygen from water
Weight oxygen from air
Gas at 32° F. and 14.7 oounds per square

inch, cubic feet per hour

Cubic feet gas per pound coal

Composition by volume:

N, per cent

CO per cent

CO, per cent

Hs per cent

Of 1 per cent

Total combustibles

Nitrogen, pounds per hour.

Hydrogen, pounds per hour

Water decomposed, pounds per hour. . .

Water decomposed per cent

Water decomposed per lb. coal, pounds.
Heat value of gas B.t.u. per cubic feet .
Total heat in gas per hour B.t.u

100 X 55514^2! =c, I

Heat m coal J

Heat to vaporize water-feed per hour.

B.t.i

Heat to vaporize water-feed per hour.

per cent

Thermal efficiency e,= "1

Heat in gas -I- heat to '

vaporize water-feed ?

'""^ Heal in coal J

Temperature of gas leaving generator .
Temperature of gas leaving washer . . .
Heat lost in washer per hour. B.t.u. . .

Heat in coal per hour, per cent

Heat lost in washer including sensible

and latent heat of water vapor
Heat lost in washer
Heat in coal

per cent .

0 5

0.5
29.5
4S.9

0.027

0.24
100

0 016
104.3

101,300

47.6%

750

121

20.950

9.S4

14,300
222,000
3.58

4.05

0.413

3.175

750
49
60.5
46.6
13.9
4.02
0.385
5.95
46

89.3
0.208
116. S
122,000

4,040
1.82

665

120

20,030

9.03

863

50

69.6

53.6

16.0

4.47

0.316

10.95

34

1 1 . 266

24.5

7.7
10.5

0.6
35.6
46.6

0.617

87^8^
0.369
125.9
132,100

7,160
3.34

600
129

18,270
8.52

19,396

9.03

23.0
8.0

13.3
0.5

36.8

53.5

550

116

19.530

8.43

20,140

8.67

14.83

14,500
215,000

62

15.5
14,200

220,000
3.52
3.33

774
50
62.4
48.0
14.4
4.03
0.263
14.375
49

0.535
129.6
151,000

545

120

19,020

8.85

19,570
9.1

14,600
225,000
3.04

49

59.2

45.6

13.6
3.84
0.298
17.25

20.7

9.7
13.3

0.7^
34.7
47.8

0.817

7.35
50.2

0.474
123.9
135,800

61.8%

16,530
7.52

550

120

18,170

19,880
9.02

the engine, which was built for the syndi-
cate by F. W. Rowlands & Co., of Birken-
head, and the consulting engineer, who
has been associated with its development
from the beginning, is P. T. Houston, of
Houston & Gall. It is intended to build
a second engine to develop from 350 to
400 horsepower, and a corresponding gas
plant, in both of which a number of im-
provements in detail will be embodied.
This plant will be installed in a vessel of
the commercial type. — Engineering.

Effect of Varying the Steam
Supply to a Gas Producer

The accompanying table gives the prin-
cipal results obtained in a series of tests
made for the purpose of determining the
effects of different rates of steam supply
in a producer making power gas from
anthracite coal. These tests were de-
scribed in this department last week,
but the table was accidentally omitted.

1.145 Mr. Maccoun's Piston Rings

998 In the drawing of a cast-steel piston

'■*-^ which was reproduced in the July 4 num-
ber (Fig. 4, page 17) in connection with
Mr. A. E. Maccoun's remarks at the Pitts-
burg meeting of the American Society
of Mechanical Engineers, the dimensions
of the piston rings were given as Ix^
inches. This was a draftsman's error;
the correct dimensions are 1x1 J s inches.

58.7
20.0
8.8

0.376
118.3
118,000

20.050

8.92

24,810
11.0

This is essentially the same in function
as some of the automatically adjustable
"arbureters used on motor-car engines.
A bell dipping into mercury is pro-
vided inside a "vacuum" chamber as
indicated. This bell is connected by a
hollow stem to a gas valve shown below
at V, and has also mounted on it at P
a loosely fitting piston, which, when in
its lowest position, shuts off all connec-
tion between the outer air and the supply
pipe to the engine. When a charge is
being drawn into the latter, the partial
vacuum produced extends to the space
above the bell through the hollow stem.
The bell therefore rises, opening simul-
taneously the gas valve V and the air
ports. The air which enters passes

and air during all changes of speed of
the engine.

Both the barrel and the heads of the
cylinders are water cooled, the water
being circulated by a small pump driven
by chain gear from the crank shaft. A
second pump supplies the water needed
for the scrubber.

For starting up the producer and for
charging the reservoir of compressed air
while in port, a small oil engine is pro-
vided. This drives a fan which gives
the draft necessary for starting up the
producer and a small Reavell air com-
pressor for charging the reservoir.

The vessel is owned by the Empire
Oil-Engine Syndicate, Limited. C. H. T.
Alston was responsible for the design of

CORRESPONDENCE

Starting a Gas Engine with
Steam

Some time ago I had charge of a city
water and light plant in w-hich two auxil-
iary generators were driven by a gas
engine. One night before starting the
gas engine to keep the steam-engine
units over the peak of the load, I found
the air compressor out of commission
and could get no air; neither could I
repair the compressor in time to start up.
The gas engine was a three-cylinder ver-
tical, with 13xl4-inch cylinders, and was
usually started by introducing air into
one cylinder. I decided to tap the steam
line and start with steam in the same
way that I would with air and change
the igniter in the starting cylinder on the
run, as I felt sure it would be "drowned
out" by the steam. Much to my surprise,
however, it fired perfectly. Of course. I
used no more steam than was necessary
and blew out the steam line until it was
quite dry before turning steam into the
cylinder. This method of starting proved
so satisfactory that it is still in use, after
three years' trial.

lola, Kan. C. J. Beach.

July 25, 1911

POWER

Engineers' Hdurs

I have been verj' much interested in
the articles appearing in Po^xer, but I
have never seen anything about engi-
neers' hours.

A few years ago I was employed as
assistant engineer in i steam plant con-
taining two boilers with a combined heat-
ing surface of about 2000 square feet,
three steam turbines of 150 horsepower
each, one surface condenser and the
necessary auxiliaries. ! got very tired
of standing 12-hour shifts seven days
per week, and consequently about the
middle of Alarch I told the ch'ef that I
would resign on ths fi's' of April, giving
as my reasons the 12-hour shift and
seven days per week.

This plant was operate;* 24 hours per
day and two firemen, two assi.=;tant engi-
neers and one chief enjjinper were em-
ployed. The chief sa:d he was perfectly
willing to put in four hours ptr day with-
out an assistant, but th<>t he had the fire-
men to consider also. If he put the en-
gineers on 10 hours per day -'.le firemen
should have the same hours and the
company would rot sanction an increase
in the force.

The following Sunday the assistant
general manager came into the engine
room, and asked mc why I wanted to
leave. I told him, and at the same time
he allowed me to make a proposition. I
explained that as long as the chief was
willing to put in four hours per day
without an assistant it would mean a
very small increase in wages to put a
man in the boiler room for that length
of time; I told him th?.t a s^atisfied em-
ployee was a good asset.

In a week the change was made, the
day crew coming on at 12:30 p.m. and
the night crew at 10:30 p.m. This left
the chief and his man from 8:,30 a.m.
to 12:30 p.m., the other man being em-
ployed in another part of the plant the
remainder of the day.

When the firemen were working 12
hours per day each man cleaned fires
once each shift. When the third man
was put on, the fires were cleaned three
times in the 21 hours, and when the coal
consumption was figured up for April
it was found to be ' j pound less per
kilowatt-hour than for March. With an
output of 400f) kilowatts per day. coal
costing S2.P0 per ton and the wages in-
creased 80 cents per day, the company
was the gainer. Of course, it may be
said that while the men were working
12-hour shifts they could have cleaned

fires oftener, but 1 have learned that the
better you treat a fireman the more
money you will be ahead in the coal pile.

A. C. KrER.MEIER.

Philadelphia, Penn.

Homemade Link Motion

As I desired to make a reversing en-
gine out of an ordinary twin slide-valve
engine, I removed the valves and got an
exact wooden templet of the valve seats.
Then a model was constructed to get
the valve movement, for the valve travel

jam nut. The connecting piece from the
eccentric stud to the link was held to
the link by bolts passing through the
pieces D and C.

The link block, shown at D, was made
from a square hollow piece of steel. The
guide bearings were made by boring
through a piece of steel with a 1-inch
drill, and then sawing through the cen-
ter of the holts with a hacksaw. The
carrying pin was threaded and screwed
in and then securely riveted in place.
The hollow portion of the block was
babbitted in position, and made to work
easily.

Short-radius rods were provided for
connection fron; the link blocks to the
valve-rod guide pins. A hanger rod con-
nected to an ordinary rock shaft and a
pair of bell cranks completed the re-
versing gear.

With tiie tools at hand it was not pos-
sible to make sny of the joints adjust-
able, but after an entire season of hard
work the link is still standing up to
business.

nnTAiLS OF Link Motion

of my gear was shorter than the direct-
motion gear. Therefore both the outside
and inside lap had to be cut down.

A bearing wss secured on the engine
frames, as at A in the illustration. Then
a piece of lx2-inch iron was forged to
the shape shown at B. This was formed
to the same ar; as the sides of the link
shown at C, which were made of I -inch
round iion. Tlie stud in the side of the
piece li was threaded and screwed in as
far £S it would go and then riveted.

The connecting piece from the back of
the link to the siud on the eccentric strap
was made of "^K-inch round stock, with a
square end welded on at the eccentric
end at E. The eccentric rods were re-
moved ind short sti'ds screwed into their
places in the straps.

The -tuds had threads long enough to
be adjustable and leave room for a

The link is rocked on a shaft or trun-
nion, as shown at A, and the block is
shifted instead of the link. When the
block is hooked up, the cutoff is short-
ened, and when the link block is in the
center cf the link there is no valve mo-
tion.

Reversing is easy, even when full
steam pressure is on the valve, because
there is no roll of two eccentrics to over-
come in shifting and the valve motion
is short and quick.

There is no valve lap to speak of and
no lead, as the valve just covers the ports
when the engine is on the center. With
all this, the steam distribution seems to
be good as the engines run smoothly and
easily, and at any speed required by the
demands of the plant.

.Famus W. Little.

Frultland. Wash.

POWER

July 25, 1911

Crowded Engine Room

Some time ago I visited a plant in an
Eastern city in which three high-speed
engines were installed in a room about
large enough for one. In order to oil
up or feel the bearings, the engineer had
to climb over the outer engines to reach
the middle one.

The piston rods cannot be removed in
any case as a heavy brick wall stands
\3y> inches from the cylinder heads. The
engines have been in operation regularly
for four years.

There were three pumps, one for salt
vater, one for water supply to boost the
pressure to the building and one to cir-
culate the water over the spray system
of purifying the air coming from the
outside of the building. These three
pumps were placed one over the other
on a separate shelf.

D. L. Facnan.

New York City.

Heat Units Required to Evap-
orate Moisture in Coal

For several days prior to a recent
boiler test, there had been a steady rain,
which continued throughout a good part
of the day of the test. This resulted
in very wet coal as shown by the chem-
ist's analysis, which indicated 6.04 per
cent, moisture. Naturally this percent-
age of moisture was deducted from the
number of pounds of coal as fired and,
therefore, did not appear in "the equiva-
lent evaporation from and at 212 degrees
per pound of dry coal."

Apparently no provision has been
made in the Standard Code adopted by
the American Society of Mechanical En-
gineers for the heat units required to
evaporate this moisture, although in a
very interesting and valuable article con-
tributed by Mr. Kent, which comprises
Appendix XXI to the code, under the
heading "Distribution of the Heating
Value of the Fuel" and referring to the
distribution of the total heat value
of the coal, under paragraph three, will
be found the following:

"Heating to 212 degrees the moisture
in the coal, evaporating it at that tem-
perature, and evaporating the steam
made f'-om it to the temperature of the
flue gases — weight of the moisture in
pounds X (212 degrees — t) + 966 -}-
0.48 (T — 212), in which T is the tem-
perature (Fahrenheit) of the flue gases
and t the temperature of the external
air."

Using this formula, 190 pounds of coal
would be required for that purpose, in
the speci.lc test referred to above, but
no actual allowance was made.

Naturally this quantity of coal was not
available for evaporation of water in the
boiler and hence the performance was
handicapped to that extent. Proper pro-

vision should be made for this in the
coal and the heat units required to over-
come the moisture in the coal should be
deducted at the same time as the mois-
ture itself.

Suppose that this particular test was
conducted to determine the acceptance of
a new boiler, installed under a guarantee
to attain a given evaporation, and while
this 190 pounds of coal was relatively
insignificant, as compared with the total
number of pounds of coal used, it would
make some difference in evaporation.
Even though it appeared only in the
hundredths column, it night have been
sufficient to barely prevent the attain-
ment of the guaranteed evaporation,
whereas had the 190 pounds been de-
ducted, the builder's guaranteed perform-
ance would have been obtained.

It so happened that no such weighty
matter hinged upon the test in question,
but as it might have been the case I
would ask the opinion of others as to
whether suitable provision should not
be mad;.

A. M. Blu.menstein.

Philadelphia, Penn.

Disk Friction Clutch

In our plant one long line shaft car-
ries five pulleys which are mounted about
40 feet apart. Each pulley drives one
large machine. The only way the ma-
chines are started or stopped is by the

ping of the machine bv the shifting of
a lever.

The clutch puliey as designed and con-
structed embraces a new idea in its toggle
movement. Fig. 2 shows the principle of
the double-disk clutch. The disk A is cast
in one piece with the sleeve B, and the
disk C can slide on three feather keys
on this sleeve but cannot turn on it. The
sleeve B is keyed fast on the shaft.

The bronze ring D carries a wooden
friction block £ and slides with its

Fig. 1. Pin Clutch

use of a pin clutch, as shown in Fig. 1.
As the pins engaged in the hub of the
driving pulleys they gave a great deal of
trouble by heating, and one had to throw
off the belt or put in the clutch in order
to start or stop the machine. To over-
come this trouble a friction-clutch pul-
ley was designed and put on the line
shaft in place of the fast pulleys. This
clutch permitted the starting and stop-

Fic. 2. Section of Disk Friction

Clutch

periphery on three feather keys attached
to the inside of the pulley rim F.

The pulley F has a brass-bushed hub
and turns on the sleeve B, and is pre-
vented from sliding laterally by butting
against an offset on the sleeve B on one
side and is held on the other by a cast-
iron collar G threaded to the sleeve. This
collar carries a steel insertion H that
can be pressed tightly against the sleeve
threads by a setscrew and so prevents
turning.

The links / shorten or lengthen the
bolts J by turning on the eccentric pin K.
This is effected by moving the collar L
in or out on the sleeve in the manner in
which all clutches are operated.

By moving the collar L toward the
clutch the link / on the pin K will turn
counterclockwise. Thus the nut on the
bolt / will move outward as well as the
bolt itself. As this bolt is swiveled to
the plate C, it will effectually draw the
plates C and A against the wood blocks
£. Disks A and C are continually turn-
ing on the shaft and when thrown into
lock they will grip the bronze plate D
and carry it around with them. Bui as
the plate D cannot turn freely on the
inside of the pulley — the three feather
keys preventing this operation — it carries
this pulley along with it.

A very small pressure throws the
clutch into gear and the power trans-
mitted is larger than one expects. Five
of these clutches are now working sat-
isfactorily. The pin clutch was not re-
moved but was used as a safety device
as the breaking of a pin indicates that
something is stuck in the machine.

J. L. Stewart and H. L. Kohlberg.

Asarco, Durango, Mexico.

July 25, 1911

POWER

145

Experimenting with CO^ Gases

Many engineers operating small steam
plants take slight interest in some of
the most uptodate methods for promot-
ing economy. Especially is this so in
the case of flue-gas analysis. Some en-
gineers believe there is little use trying
to get the manager of a small plant to
buy a C0» apparatus and others say
that they hire the best firemen they
can find and expect them to get results,
without attention f'oin the engineer, or
get out. This last method is wrong, for
it is in the boiler room that the greatest
preventable losses occur and where the
engineer has the opportunity to make the
greatest saving.

I became intjrested in fue-gas analysis
about a year ago and purchased a hand
analyzer. I could no' afford to buy a
recording instrument and I knew that
the manager would not buy it. I have
never regretted tlic expense; in fact, I
regard it as the bes* investment I could
have made, for by the use of this in-
strument and by experiments I have
learned more concerning economical
combustion than ! could in any other
way. The plant burns oil under return-
tubular boilers so the hand instrument
probably "fills the bMl" better than would
be the case if coal were used, especially
as the load is con-.paratively steady.

My first analysis showed about 8 per
cent. CO:, and I started on a hunt for

loss as air will leak into the furnace.
With the new setting it is possible to get
from 13 to 14 per cent. C0=. The fur-
naces are coated every other month
with whitewash in whicii fish glue has
been dissolved. Just as little air is ad-
mitted to the furnace as is possible and
at the same time secure smokeless com-
bustion.

The gain in economy is quite notice-
able as the factory is now turning out
about 17 per cent, more of the finished
product per barrel of oil than was the
case when the analysis showed 8 per
cent. CO:, all other conditions being
equal.

Some of my .Tcqua'ntances express
themselves as being dissatisfied with the
results of their "aralvzing," and this I
think is caused by their expecting too
much of their instrument. The CO,
analyzer will not of itself stop any air
leaks or save any fuel, but will help the
engineer to do so by showing him just
how little air he can supply to the fires
and not produce CO.

T. P. WiLLIA.VS.

Brownsville, Tex

Faultily Designed Tank Valve
and Float

About four years ago I installed a
pump and receiver outfit in which a float

fiat links F, which were suspetided in the
chamber B by a lug, as shown.

Although this arrangement looked all
right the stuffing box would leak and
cause the receiver to become steam
bound. In order to pack the stuffing box
it was necessary to remove both heads
from the chamber B, but there was so
little room in it that it was difficult to
pack the valve stem.

I proceeded to alter the pump in the
following manner: The balanced valve
A was disconnected from the top of the
chamber B and from the steam line to
the pump. The receiver head was then
unbolted at H and the float withdrawn
from the receiver. The lever connecting
with the float G proved to be a piece of
gas pipe and was substituted by a brass
lever having a connection on one end, as
shown at C in Fig. 2.

An old globe-valve bonnet was screwed
to one of the heads of the chamber B,
as shown at /, rig. .?, and the other head
was drilled and threaded to receive the
brass plug K. This plug had a K'-inch
hole drilled into the inner end to serve
as a bearing for the end of the stem L.
A small crank M was then made to fit
on the other end of the stem L and a
small hole was drilled in the other end
of the crank to connect with the forked
end N of the valve stem by means of a
small bolt.

The hole in the top of the chamber B

Fia 1. Side Elevation of the Return
Tank and Pump

air leaks. -I did not Pnd many and only
nicceeded in raisirg the CO; to 8.5 per
cent.

My next step was to give the brick set-
tings two coats 01 wh'te lead and oil
paint which helped some, and the COi
increased to about 1 1 per cent. Then as
•he furnaces were in bad shape, the
boilers were reset, but no air spaces
were left In the walls, as was formerly
•he case.

The result convinced me that an air
■pace in a furnace wall is a source of

Fic. 2. End Elevation of Tank and
Pump

Fig. 3. Details of Valve
Arrangement

and balance valve controlled the admis-
sion of steam to the pump, as shown in
Fig. 1. The pump was defective because
of the manner in which the throttle valve
and the float were connected.

This throttle valve A, Fig. I, was
mounted on top of an overhanging cham-
ber B, with its stuffing-box end project-
ing down into the chamber that was
bolted to the end of the receiver. The
end of the valve stem C was connected
to the end of the float lever by a pin D.
The float lever £ fulcrumcd between two

that had oeen occupied by the valve was
closed by bolting on the plate P. the joint
being made tight by first inserting a rub-
ber gasket.

After assembling the parts, and plac-
ing the balanced valve in position, a
lubricator was connected to lubricate the
stem of the balanced valve as well as
the cylinder of the oump. The valve and
float were then adjusted and no further
trouble was experienced.

George Little.

Passaic, N. J.

146

POWER

July 25, 1911 ;,

Dniininj^ Compressed Air

In the issue of Power for June 20, on
the "Inquiries of General Interest" page,
a correspondent tells of the trouble he
has with water and some oil in his com-
pressed air, and suggests that "if the
air were cooled to a point lower than it
would again become, and drained at the
point of lowest temperature, it would not
again form water." The latter phrase
cannot, of course, be taken literally, as
the air cannot make more water than
it carries with it into the compressor,
and whatever water it drops after leaving
the compressor it cannot again pick up,
or "form water," after it has passed
along and left it behind.

The editor's suggestion of the after-
cooler is undoubtedly correct, but the
further statement that the air should then
pass to a large air receiver "where the
remaining water and oil will fall to the
bottom and may be drawn off" represents
theory rather than practice, and the
theory is defective because it ignores
some of the conditions.

The inconvenience, actual delay and
expense caused by water in the pipes

Fig. 1. Air Receiver

are sufficiently familiar to all who have to
do with compressed air, and the methods
of disposing of the water are now getting
to be quite generally understood. One
thing very soon learned is that an air
receiver will not get rid of the water.

Fig. 1 is a snapshot of an air receiver
outside the compressor house of one of
the New York State barge-canal con-
tracts. The compressor was electrically
driven by current generated at one of
the falls of the upper Hudson. There
was no aftercooler and the engineer said
tJiat he opened the drain cock at the re-
ceiver every day or two but did not get
enough water to pay for the trouble.

Comment,

criticism, suggestions
und debate upon various
artides .letters and edit-
orials which have ap-
peared in previous
issues

About a quarter of a mile along the
pipe line, however, there was an en-
larged and depressed chamber formed in
the line; here the water could be drawn

which served the double function of re-
ceiver and separator, and here the re-
mainder of the water was taken care of.

All normal atmospheric air when com-
pressed to, say, one-sixth or one-eighth
of its volume and cooled to its initial
temperature contains more water than is
sufficient to saturate it, the surplus of
moisture still remaining in the air in a
cloudy condition, and it does not sud-
denly and immediately drop out of the
air any more than a cloud in the sky
drops as soon as it is formed.

Fig. 2 shows a highly efficient after-
cooler and its attached air receiver at

Aftercooler with Receiver Attached

off in considerable quantities, and about
another quarter of a mile further along
the line, where most of the air was used,
there was a locomotive-type steam boiler

the Rondout siphon contract of the T. A.
Gillispie Company on the new water sup-
ply for New York City. The air here
enters the receiver low down and is dis-

July 25, 1911

charged near the top on the side not
visible, but if it had been connected the
other way '"t would have made no par-
ticular difference; it did not get rid of
the water.

In the horizontal main pipe line, taking
the air delivery from all the compressors,
was placed a drum about four times the
diameter of the pipe and perhaps double
the diameter in length, with a number of
vertical baffle plates attached alternately
to the top and to the bottom. The air
passing in at one end and out at the
other would zigzag between the plates,
wetting them as it went, and the water
accumulated at the bottom had to be
drawn or blown off as often as necessary.

When the air is in the supersaturated
condition which results from the after-
cooling it is not difficult to separate the
surplus water, but some means must be
provided, or at least more time must be
allowed than it has in passing through
the receiver. Any effective steam sep-
arator is good also for wet air. Even as
the air flows along a horizontal pipe it
wets it as it flows and the water may be
drawn off at the low places. If it is not
drawn off it is carried along and is
found in the exhaust of the tools or ma-
chines operated. Water when in this
condition, wetting and clinging to the
surface it may come in contact with, is
easily taken care of.

The necessity of providing some means
of taking the water out of the air after
it is condensed and released seems to be
the one thing in the circle of air-com-
pression operations now most often neg-
lected. Whatever the apparatus or ar-
rangement employed for the purpose, it
would seem to be certainly worth while
to adopt it for only slight initial cost will
be involved ; there is no expense in the
work of separation.

Frank Richards.

New York City.

On Being One Sided

I read with interest the editorial in
the June 27 number entitled "The New
York Edison Company's Advertisement"
and containing a letter signed I. A. of E.
The fact is that we want the Edison com-
pany's advertisement, also such articles
as that by George P. Gilmore in the
June 20 issue. When two sets of men
differ in opinion there is no gain for
either in trying to dodge or suppress the
arguments of the other. The mistaken
party will provide its own undoing If
given the opportunity. The trick Is to
meet opposing arguments with still
stronger ones.

No engineer, superintendent or owner
with any experience could be induced to
electrify his plant by reading Mr. Gil-
more's article for the simple reason that
his claims are too extravagant.

L. Johnson.

Exeter, N. H.

POWER
Still for Drinking Water

In response to Mr. Eldred's inquiry in
the June 6 number, I submit the accom-
panying sketch which illustrates the
manner in which I obtain an ample sup-
ply of pure water for drinking purposes.

Arrangement for Collecting Drinking
Water

The valve A is throttled down so that
it just a little more than drains the sep-
arator. For tanks I use oil barrels that
have first been burned out so that the
inside is lined with a coating of charcoal.

In another plant where I worked, one
of the returns was tapped and the water
of condensation was piped to a metal
storage tank. In this manner ample drink-
ing water was obtained for 50 employees.
S. J. Perry.

Dover, Idaho.

In the June 6 number, E. G. Eldred
inquires how to construct a condenser
so as to obtain about two gallons of good
drinking water per day. The accompany-

?j Pipe/0 long

Arrangement for Condensing Drink-
ing Water

ing sketch illustrates the construction of
one which may be suitable to his needs.
The condensing coil may be placed in
any convenient location. If the heater
i3 of the open type, tap Into the exhaust
line before it reaches ihe heater.

147

If the water tastes too flat, put a little
salt into it, or, better still, put in some
rav/ oatmeal, which will make a most
refreshing drink.

William Nottberg.

Kansas City, Mo.

Asleep on the Job

The editorial in the June 13 issue
"Gathering Them In" and the letter
"Asleep on the Job," by Mr. Hyde, are
two interesting sketches. Many engi-
neers are asleep; they do not or cannot
realize the conditions that exist today.
Unless the man who calls himself an en-
gineer will keep abreast of the times he
will fall by the wayside.

Just lately I observed a case in point.
The engineer was economical of packing
and waste and oil, but he slept alongside
his leaky balanced flat-valve engines
until something happened. He thought
that nothing could be said against these
machines as they were running smoothly
— leaky machines generally do run
smoothly — and if anyone had hinted at
leaky valves he would have felt insulted.
Many plants are being closed down be-
cause of just such conditions. The en-
gineer makes no test; he does not know
whether the boilers are at fault or the
engine. The plant runs on, as the pro-
prietor depends upon his engineer, who
has gone to sleep. Then comes the out-
side power man, and before the engineer
wakes up and can produce any records
a contract has been signed.

I recently met a case where a boiler
test was desired by the owner. I
looked over the plant and found two
nice-running "thieves" bleeding the cash
drawer — a balanced fiat-valve and a
round-valve engine. No attention had
been given to the take-up of wear on the
valves, and I could easily see why a
boiler test was wanted. The poor boil-
ers catch the blame. It is a good plan,
however, to start with them and follow
the steam pipe; you will surely find some
"niggers in the woodpile."

As Mr. Hyde says, the isolated-plant
engineer must keep awake; this is the
whole story. Associations and organiza-
tions will do no good if they fail to first
awaken a lot of us who are sleeping.

Look the plant over and see if you
have a similar case. Watch out or the
central-station man will get you! The
engineer should know what he is doing
by actual trial and by keeping records,
and the records should he compared with
those of other plants. The central-sta-
tion man docs not approach the fellow
who runs a plant on a systematic and
scientific basis — the man who can tell
the manager what current cost for the
same month of last year. This fellow
holds his job as he is earning dividends
for his company. Many men simply
burn coal without knowing the cost or

143

POWER

July 25, 1911

results; if the manager should ask how
much ash the coal contained they could
not give a good guess. This may seem
as if I were coming down hard, but it
does not hurt to tell facts. Unless these
facts are seen by many engineers I am
afraid there will be a glut in the market
of engineers or should 1 say throttle
turners?

C. R. McGahey.
Baltimore, Md.

Unnecessary Clearance Loss

Referring to my letter in the April 25
issue entitled "Unnecessary Clearance
Loss," the illustration shows an engine
of the Corliss type in which the exhaust
valves would come in such a position as
to make it impossible for the openings
leading to the relief valves to be in the
posit'on shown. The engine referred to
in this letter was an Atlas four-valve, in
which the valves and ports are in the
heads; this allows the openings for the
relief valves to be on the bottom, as
shown, the Atlas being about the only
engine in which it would be possible to
place the relief valves in this position.

S. KlRLIN.

New York City.

Writing for the Technical
Paper

Extended discussion of a particular
theme, unless each contribution thereto
opens up a new and valuable line of
argument, is very apt to grow tiresome
to the reader; hence the writer will but
briefly approach the "writing" subject
for a second time. It would appear,
however, that Mr. Williams, in the issue
of June 20, commenting upon the writer's
reply to his former communication, is
laboring under a slight misapprehension
of its full intent and meaning.

The exact explanation may be summed
up by taking the four words used on
the editorial page of this same issue,
namely, "Opportunities for Self Advance-
ment"; the writer inferred one of them to
be a betterment of one's self, and whether
the man is 16 or 60, it is never
too late. Mr. Williams notes that the
writer's remarks are applicable when one
has a "typewriter, an Encylopedia
Britannica, and a Century and a Funk
& Wagnalls' dictionary." This is wrong;
they apply at the youthful stage, when
we learn to think for ourselves, and
they never end while we live.

A typewriter may assist in making neat
and legible copy, but in the majority of
cases handwriting will answer. It takes
brains, intelligence and common sense
to compile a contribution really worth
while, and the machine lacks these fea-

tures. As for the encyclopedia, Power,
week in and week out, is for the engi-
neers about the best to be found, and for
practical, uptodate information has got
the one mentioned "done to death." As
for the dictionary to be "obtained for a
trifling sum," put Power to this use again,
and in company with the quarter dic-
tionary it is a combination hard to beat.

Mr. Williams makes notation of the
"literary monument" and "the new writer
who has neither time nor patience." The
former in the technical field is not looked
for; the man we would like to hear
from is he who follows "the papers" and
recalls contributions to which this can
be applied determinately. There is a
vvide call between "practical" and
'literary."

A man who has "neither time nor
patience" will not take proper care of
his plant; he is usually the fellow who
spends half his time in "resting" and
the other half in bemoaning that he
"isn't appreciated." If this man has no
time or patience to make good in his
work and to better his condition, he sure-
ly is not the m.an to tell the other fellow
"how to do it," and this is what Power
is after.

The writer will not intrude again with
this topic, and for conclusion offers the
following advice — it may be compassed
in three words — do it right! Make the
opportunity for self-advancement bear
as much fruit as the opportunity to legiti-
mately earn a dollar. Understand what
you read, and remember that the other
fellow must understand what you write.
Joe Smart.

Los Angeles, Cal.

Sizes of Turbine Steam and
Exhaust Pipes

1 was much interested in the letters of
Messrs. Neilson and Kent, discussing the
subject of sizes of exhaust pipes, brought
about by the publication of my curves
in Power for February 21.

Referring first of all to Mr. Neilson's
letter in the issue of March 28, he states
that my curves are not based on correct
principles, nor are they truly scientific.
I agree with him entirely that the de-
velopment of this chart is not based on
such a careful study of conditions as his
formula, but I think the curves are more
commercial than his formula. Mr. Kent
had already raised one question I had
in mind when studying Mr. Neilson's
formula, and that is the length of pipe;
but in addition to this another point is
overlooked which in the writer's mind
is much more serious, the layout of the
piping. There should surely be some
correction factor for all elbows, bends,
etc. Again, this factor should be fur-
ther split up, covering the nature of these

bends; for instance, it is obvious that
a greater drop with a sharp bend or tee
is expected than with an easy bend.

One other point, to go into this matter
in a truly scientific manner, is the nature
of the inside of the pipe. It is obvious
that in any comparatively small piping
the friction in a rough cast-iron pipe
must be perceptibly greater than in a
smooth copper pipe.

Mr. Kent has already raised the ques-
tion of the nature of the turbine exhaust,
whether this be correctly coned and
whether it be tangential to the casing or
radial, so that while Mr. Neilson's for-
mula is, I acknowledge, scientific, it is
not by any means complete.

If we take Mr. Neilson's formula and
add to it a few more factors, taking
care of all possible contingencies, we will
have a formula both unwieldy and, I
consider, impracticable, for reasons I will
endeavor to explain. Supposing we de-
sign an exhaust pipe to pass 10,000
pounds of steam per hour at a 27-inch
vacuum. How often in practice will this
pipe pass 10,000 pounds of steam per
hour at a 27-inch vacuum? If we design
our pipe on truly scientific principles, all
our theories are knocked on the head for
a greater percentage of the time at which
this pipe is operative. When we design
our turbine for given conditions, we be-
gin by assuming that our actual load
will be somewhere near this amount, but
anyone who has had experience in cen-
tral-station work knows that if the ma-
chine was originally designed for 3000
kilowatts, that machine operates at ex-
actly 3000 kilowatts for a very small
percentage of the time. Mr. Neilson
claims that an exhaust pipe designed
with the velocities given in my curve,
namely, 400 feet per second, will not
work well in practice. I have been re-
viewing a few actual cases where veloc-
ities have varied anywhere from 200 to
800 feet per second, but there has been
no indication of serious troubles due to
velocities being too high or too low.

When I published my curves I did not
expect all engineers to agree with me
that a velocity of 400 feet per second
was best, but it is a very easy matter to
interpolate from these cur\'es for any
other velocity that it is desirable to em-
ploy. If I had considered for a minute
that the curves as published were the
correct and only proper sizes to use, I
would not have given the velocity, en-
tropy, etc., on which the curves were de-
veloped, and I cannot help feeling that
the curves as published, used with the
discretion expected of any engineer, will
work as well in practice as a long for-
mula which, when figured out. is only
good for a condition existing for probably
only 2 or 3 per cent, of the time the
pipe is in service.

W. J. A. London

Hartford, Conn.

i

July 25, 1911

POWER

K9

Issued Weekly by the

Hill Publishing Company

Job.-* A. Hill, Prp?. oii.i TrtiL^. RoB-y McKkan-.S^.':,.

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ruler den LiudeQ 71— BerUn, N, \V. 7.

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tnust be given — not necessarilj* for pub-
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Pay no money to solicitors or agents
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to the London Office. Price 21 Shil-
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Entered as second class matter, De-
cember 20, 1910. at the post office at
.New York, New York, under the Act
of March 3, 1879.

Cable address, " Powpcb," N. Y'.
Business Telegraph Code.

CIRCVLATJO.\ UTATEMliXT

Of thig itrue, 31,000 copies are printed,
yone sent free regularly, no returns from
I neir* companies, no back numbers. Figures

Contents f

Hydroelectric Plant at Virnon, Vt

Hydraulic nammcr Test for Boilers

Boiler Explosions In England

Notes on the Design of a Drip System . .

Temperature Conversion Chart

Cylinder Oil Consumption Tests

Pre%-pntlng Oas Explosions In Boiler Up-
take

Automatic Step Bearing I'ump

Loss of Head In I'Ipes

Fidler's Earth as an Oil Filter

Ventilation of Turbine generators

Parallel Operation of Alternators r»rlven
by Water Wheels

Bqulpnient of the Gas Power Yacht
"Progres.s"

Effect of Varjing the Sleam Supply to
a 0ns Producer

llr. Maccoiin's I'lslon Rings

Starling a Oas F:nglne with Steam

Practical Letters:

Engln<-erfl* Hours. ... Homemade IJnk
Motion .... Crowded Engine Room
....Heat Units Reipilred to Evap-
rate Moisture In Coal . . . . Iilsk Frlc-
Mon Clutch. .. .Experimenting with
fO. r;avK .... Faultily lieslgn-d
Tank Valve and Float 143-

fNlcusslon Letters :

I>rRlnlng Compressed Air... On Be-
ing One Hided Still for firlnklng

Water. . Asleep on the .loti. . . .Un-
nocessary flenranre Ixtss. ... Writing
f/>r the Technical Paper. ... Slirs
of Tiirlilne Sleam and Exhaust
•'Ip" 140-

EdlltTlnls 140.

Water Cooling

An Adsorption Kink

f*1''sranre In Compressors

Prpvenflne Red Core In Ice

Knowledge is Power

In a New England city a realty com-
pany erected two eight-story factory
buildings which were rented with heat
and power for manufacturing purposes.
No engines were installed as the man-
agement was convinced by the agent of
the central station that at its flat rate
for electrical energy, one and three-
fourths cents per kilowatt-hour, the
realty company could not afford to gen-
erate current for its tenants. After
a year it was evident that no dividends
were probable under the circumstances
and a committee was chosen from the
board of directors to find the leak. The
chairman of this committee got permis-
sion to consult his engineer. The treas-
urer's books were opened to the engineer
who, after a thorough examination, said:
"You are not making money because
you are paying to the central station
what should be your profit in this busi-
ness. Steam must be used all the year
round and during six months of the time
so much is needed that an engine large
enough to generate all of the current
used will cost you for fuel for operation
practically five per cent, of the amount
burned if the exhaust steam is used for
heating the buildings. The additional
cost of operation will be the wages of an
engineer, the interest on the investment,
depreciation and taxes.

"With a properly designed plant cur-
rent can be made for less than is be-
ing paid for it now during the time no
heating is necessary and almost for noth-
ing so far as fuel is concerned during
cold weather, for the engineer will more
than save his wages by simply being on
the job and seeing that intelligent fire-
room practice is followed."

After some deliberation the board of
directors adopted the suggestions em-
bodied in the remarks of the engineer.

At the end of the first month of op-
eration, which was in the early sum-
mer, when but little steam was required
for healing and when opcratlne condi-
tions were not the most favorable, the
expense sheet showed that the invest-
ment was paying interest at the rale of
twenty-four per cent.

With an cxampla of the possibilities of
the isolated plant so plainly showing
that the central station cannot compete
with it under any ordinary condition of
service, there is no reason why the en-

gineer should fear the encroachment of
central-station service.

Wherever comparative tests have been
made on an honest, intelligent basis the
results have usually shown the advan-
tages of the isolated plant. If the en-
gineer knows what he is doing and what
it costs to do it, no outsider will be
able to convince the owner of the little
plant that central-station serA'ice is cheap.

But if he does not know these things
the trained salesman will sweep him off
his feet with a flood of misinformation
that he cannot refute.

At no time in the history of steam-
engine operation has the phrase "knowl-
edge is power" been more fitting than
now. It is the engineer's business to
know, and where he knows he is safe.

Marine P.ngineering

When visiting a modern power house
one is often impressed by the excellent
features of design embodied in the gen-
eral layout. But let the same person
take a trip through the engine room of
one of our large transatlantic liners and
the stationary plant will be entirely
eclipsed by the more intricate design of
the floating plant.

Without attempting to detract from the
glories of the designer of stationary
plants, it may be truthfully said that the
problem of the marine engineer is de-
cidedly more complex. In stationary
practice the designing engineer is con-
cerned chiefly with meeting the condi-
tions of operation, space being a second-
ary consideration, except in special cases.
On the other hand, in marine practice,
while the operating conditions are less
variable, space and weight are factors
of paramount importance. Not only is
it necessary to keep the weight within
certain limits but it must be so dis-
tributed as to meet both structural and
displacement requirements. As for space,
every available foot is utilized and this
requires much planning and scheming
on paper before the actual construction
begins. This applies especially to the
piping. An idea of the compactness of
the equipment on a modem liner may be
gained from the fact that the main en-
gine room of the "Olvinpic" (containing
many of the auxiliaries! covers only
about 0.25 foot of floor space per horse-
power.

Another important feature in marine
desien is continuity of service. There

150

are no spare units to be thrown in, as
are usually provided in land practice,
and all repairs have to be made with
thg limited facilities at hand.

In view of the many fine problems in
design offered by marine engineering it is
deplorable that this profession should
have declined to such an extent in this
country, all large vessels, excepting Gov-
ernment vessels, now being built on the
other side of the Atlantic. The cause
of this condition is too well known to
need comment, and, moveover, there ap-
pears to be no relief ahead. Meanwhile
American engineering talent lies dormant
in this field.

Going over die Chief's Head

It has been stated time and again that
the efficient, capable man will always
find a position that measures up to his
ability, but the case cited will show where
this contention did not hold good.

A Power representative recently called
at a small steam plant which was op-
erated by an intelligent young man whose
conversation made it appear that he was
capable of handling a much larger in-
stallation. He expressed the wish that
he could obtain a better position.

A few days later this man's case was
mentioned to the master mechanic of a
large manufacturing company. "He is a
good all-round man," said he, "but he
does not know his place; he goes over
the head of his department and causes
almost constant trouble. He has worked
for me, but I had to let him go because
of this one serious fault."

It is not reasonable to expect that a
chief engineer will retain an assistant
who is continually taking his grievances
to the general manager or president,
thereby going over the chief's head, and
the man who does so can expect dis-
missal sooner or later. The chief engi-
neer of a plant is its official head. If an
assistant engineer thinks he is being ill
treated, it is better to take the matter up
with the chief than to ignore him and go
to someone higher up.

Looking at the matter in another light,
going over the head of a chief smacks
of snobbishness; it also makes it appear
that a square deal cannot be had from
him. There are but few chief engineers
who are not interested in their assist-
ants, and there have been hundreds of
them who have put themselves out to
assist their subordinates.

One chief engineer adopted the plan
of asking his assistant's advice about
, various changes to be made, though he
had previously formulated a plan and
merely gave the assistant an opportunity
of expressing his ideas. If they agreed
with the chief's plan they were adopted
and the assistant then knew that his plan
was a good one. This practice soon
aroused a general feeling of fellowship

POWER

July 25, 1911

in the plant, and the men knew that the Rotundity, Not Type of Joint
chief would fairly adjust any grievance ^j^^ Essential in Shell

they might have. Boilers

The discussion at the recent meeting
of the American Boiler Manufacturers'
Association of the question, "Will the
present type of butt and strap joint fail
frequently in the future as the lap seam
has in the past?" led to the conclusion
which Power has several times advanced,
that the butt and strap joint will not be
a panacea for joint troubles. The cracks
which lead to the failure of lap joints
and several of which have appeared in
butt-strapped joints are due to the re-
peated bending of the metal about a
fixed line. Under pressure the boiler
shell tries to become circular. If it is
not circular to start with, there will be
some movement every time the pressure
varies, and if the movement is concen-
trated upon some particular line a break
will finally occur just as a wire will
break when it has been bent back and
forth a sufficient number of times around
the same point.

With the lap seam it is impossible to
make a boiler circular in the first place;
with a butt-strapped joint the shell may
be made truly circular so that there need
not be movement. There was some talk
in the discussion about the effect of hav-
ing a part of the circumference so much
thicker and heavier than the rest, but we
do not see that there will be any ten-
dency to bend the thin single sheet
around the edge of the thicker double-
strapped portion except by unequal heat-
ing if the structure is round to start with.
The advantage that the butt-strapped
joint offers is that with it the shell may
be made round. If the shell is allowed
to var>' from a true circle the use of a
butt joint will not save it.

Central Station Service

There is an old saying, "Do not put
all your eggs in one basket" and a mod-
ernization of it, "Put all your eggs in
one basket and watch that basket." No
matter how well designed or constructed
a power plant may be, it is practically
impossible to supply energy one hundred
per cent, of the time, although this figure
may be closely approximated. The weak-
est link in the operating chain reveals
itself, now at one point, now at another,
and even the complete duplication of
plant and transmission system has not
proved itself immune from that unfore-
seen and inexplicable perversity of inani-
mate objects which results in their
simultaneous shutdown. Often these
shutdowns are comparatively trivial, the
current supply being only interrupted
for a fractional part of a second, but,
strictly speaking, any interruption of ser-
vice is inexcusable. There is one daily
report which should reach the highest
official of every concern operating a
power plant. It should give the time and
duration of every incident which caused
the operating potential to drop below the
normal, even though it is only a flicker
of the lamps; and should then be tabu-
lated and compared with past records.
The daily-shutdown report has been the
spur under which the steel mills have
attained their records of production.

How the Empire State Classes
Engineers

\

While the united engineers' societies
of New York City are agitating for the
revision of the proposed charter in Sec-
tion 792 so as to provide for real ex-
amination of engineers by engineers the
printed copies of the charter as it is
before the legislature have appeared. The
sections between 790 and 800 have been
left out altogether, but back in Chapter
XV, which deals with the Police Depart-
ment, appears the following:

"The department shall have general
jurisdiction over and supervision and
regulation of pawnbrokers, hawkers,
peddlers, junk-shop keepers, junk boat-
men, cartmen, dealers in second-hand
merchandise, intelligence-office keepers
and auctioneers; and the inspecting, test-
ing and issuance of license certificates
for steam boilers, and the issuance of
certificates of qualification for the care
and control of steam boilers, and for
the purpose of ascertaining the qualifica-
tion of applicants for such certificates
the commissioner may detail a board of
examiners to conduct examinations."

Safe Boiler Construction

Among sll the boiler failures during
recent years there have been but three
which were of the butt-and-strap con-
struction. While not all of the other
failures have been due to the lap joint,
such a large proportion have failed at
the seam that it proves that form of
joint to be unsafe. None of the butt-
and-strap failures were explosive, and
were all due to the same cause that
makes the lap seam dangerous; the shells
were not cylindrical and the changes of
pressure permitted the same destructive
bending in the sheet that takes place
in the lap-seam form of construction

With the present high standard of ex-
cellence in boilermaking machinen.' and
the available skill to operate it, it is pos-
sible to make boiler shells with butt
joints which are truly cylindrical and
which will not be affected by those'
causes which will in all cases eventually
crack the shells of all lap-seam boilers.

July 25, 191 1

POWER

Power of Current TVaterwheei

How much power can be derived from
a wheel of the ordinary- paddle or water-
wheel construction anchored in an open
stream something on the principle of an
undershot waterwheel; the size to be 14
feet diameter by 20 feet long; the ve-
locfty of stream 7 miles per hour?

A. P.

According to the experiments of Ponce-
let and others, the best effect is ob-
tained when the wheel is immersed to
one-fourth of its radius. This is 40 per
cent, of the theoretical energy of the
cross-section of the water intercepted.
The diameter of the wheel being 14 feet,
one-fourth of its radius would be 21
inches. With this immersion for a wheel
20 feet long, the cross-sectional area of
intercepted current would be 35 square
feet.

A velocity of seven miles per hour is
10.26 feet per second; hence the wheel
would intercept 35 -^ 10.26 = 359.1
cubic feet or 22,443.7 pounds of water
per second. The energy represented is
22,443.7 X 10.26-

64.4

36,732 foot-pounds

per second = 66.78 horsepower. The
greatest effect obtainable being 40 per
cent, of the energy in the water, the
power obtainable from the wheel would
be 40 per cent, of 66.78 horsepower, or
26.71 horsepower.

Flow of Superheated Steam

Inquiries are often made regarding the
loss of pressure in pipe lines conveying
superheated steam, particularly where
there are a number of elbows and other
connections. In the use of saturated
steanr such a loss is known to exist, but
what happens in the case of superheated
steam? The temperature naturally de-
I creases, due to radiation but is there any
i drop in pressure before reaching the
point where the steam cools to same tem-
perature as the boiler-pressure steam?

Various papers have been read and dis-

Ctisscd relative to the merits of super-

I heaters and the use of superheated

) steam, hut as far as I can ascertain no

one has plven any specific Information on

this point.

A. V.
So far as is known there arc no re-
liable data relating to the loss of pres-
sure in superheated steam flowing
through pipes. There must be a drop
of pressure sufficient to overcome the re-
sistance of How. This would be probably
'ess with superheated steam for the same

velocity on account of the less density
of the medium, but might be more for the
same weight delivered on account of the
greater velocity required.

Gage Glass and Water Level
Why does the water glass not show
the true level of water in the boiler?
W. L. B.
The water gage does show the true
level of the water in the boiler if it is
properly connected and the openings are
of sufficient size and unrestricted.

Efficiency of Diagonal Seam

A 60-inch jMell built of 5/16-inch plate
having a tensile strength of 60,000
pounds per square inch has a slngU-
riveted patch for its entire length. The
patch is 20 inches wide at one end and
6 at the other. The rivet holes are 11/16
inch in diameter and the pitch i.s 2 inches.
Assuming the rivets to be of steel and

5'-0'-

Patch with Diagonal Shams

the efficiency of the joint to be 41 per
cent., what Increase In efficiency is ob-
tained by the pa'ch ream being idip.hfly
diagonal to the axis of the shell?

E. L. D.
To find this in a simple manner multi-
ply the length of the patch scam in
inches bv 41. the efficiency of the joint,
and divide the product hy fiO. which
is the length in inches measured alonit

ine parallel to the axis of the
cylinder. Thus, as the patch seam meas-
ured along the rivet centers of the
diagonal seam is 60.4 inches,

60.4 X 41 .

^ = 41.27 />cr cent.

the efficiency of the diagonal seam. There
is a gain of 0.27 per cent, in efficiency.

IXingerous Fire Crach
How can 1 tell when a fire crack is
dangerous?

E. H. C.
Fire cracks are dangerous when they
extend beyond the rivet hole into the
plate and when leaks, if any, cannot be
stopped.

Grooving in Boi/er S/iccts
Where is grooving found in a vertical
and locomotive boiler?

T. P. T.
Grooving usually occurs near to and
parallel with a rigid seam.

Pitch at Girth Seam
Why is it that in a double-riveted lap
joint the rivet in the inside row next to
the girth seam has a greater pitch than
the rest of the rivets?

C. G. F.
Double-riveted lap scams have a wide
pitch next to a girth scam because the
rivets in the two rows are staggered and
therefore in starting a seam the pitch
on one row must be wide. The spacing
on the outer row is kept uniform to per-
mit calking. The stiffening effect of the
girth scam more than compensates for
the lack of a one-half rivet at this point.

Safety Valve Areas

How are safety-valve areas deter-
mined ?

S. V. A.

The formula used hy the Board of
Supervising Inspectors of the United
States for the area of safety valves is

If

a = 0.2074 X „

where

a — Area of safety valve in square
inches per square foot of
grate surface;
W — Pounds of water evaporated
per square foot of grate sur-
face per hour;
P = Absolute pressure in pounds
per square inch.

152

POWER

July 25. 1911

Water Coolinj^^

By F. E. Matthfvcs

Since the specific heat of water is
unity, the number of heat units to be
extracted in order to produce a given
drop in temperature of a given quantity
of water is found by simply multiplying
the weight in pounds by the range cooled
through in degrees.

If, for example, 30,000 pounds of
water is to be cooled one degree, 1000
pounds 20 degrees, 4000 pounds 50 de-

that given for 3, or 2.0840, making 36,817
tons, must be taken.

REFRIGER.\TION DUTY IN TON.S PER 24 HOURS REQUIRED TO COOL
1000 C.'iLLON.S OF W.\TER

1000

(iallon.': Cooled per

Degrees

1000 Gallons Cooled per

Degrees

Cooled

Minute

Hour

24 Hours

Cooled

Minute

Hour

24 Hours

1

41,68 •

0,6946

0.02894

21

875.28

14.. 5879

0.60778

2

83 , 36

1,3893

0,05789

22

916,96

15.2.824

0.61672

3

12.1,04

2.0840

0.08682

23

958.64

15 . 9770

0,65564

4

166 , 72

2.7786

0,11577

24

1000,32

16 6716

0 69456

208 . 40

3,4733

0,14471

25

1042,00

17.3664

0.72352

6

2.'J0 - OS

4.1679

0,17364

26

1083.68

18.0612

0,75248

7

291,76

4 , 8646

0.20259

27

1125 36

18.7598

0.78142

8

33.3 . 44

5 , 5590

0.23154

28

1167,04

19.4584

0,81036

9

37."). 12

6,2519

0.26048

29

1208.72

20.1491

0.83931

10

416,80

6 9466

0.28942

30

1250.40

20.8399

0 . 86826

11

458 , 4S

7,6412

0.30836

31

1292.08

21.5379

0.89721

12

500, 16

8,. 3358

0.34728

3-2

1.333 , 76

22 . 2360

0.92616

1.3

541 ,84

9 0306

0.37624

33

1375.44

22 . 9289

0.95510

H

5S3 52

9,7292

0.40518

34

1417.12

23.6218

0.98404

15

625 , 20

10,4199

0.43413

35

1458.80

24.3147

1.01298

16

666 , 88

11,1180

0.46308

36

1500.48

25,0076

1.04192

17

708,56

11,8109

0 . 49202

37

1542.16

25.7023

1.07086

18

750.24

12 , 5038

0.52096

38

1583.84

26,3970

1.09980

19

791.92

13.1985

0.54990

39

1625.52

27.0918

1 . 12874

20

833,60

13 8933

0,59884

40

1667.20

27.7866

1 . 15768

the number of barrels of 31 gallons by
the specific gravity of the woit and this
product by the specific heat of the wort
corresponding to the specific gravity.

To cool 40 degrees 100 barrels of wort
per hour having a strength of 12 per
cent., for example, it is found fron
Table 2 that the refrigeration require
to cool a like amount of water is 86. .J
tons. If the specific gravity of the w -t
is 1.049, the weight of the wort coo °d
will be 1 .049 times as great as for wf er,
but if the specific hert is only 0 ^16,
the refrigeration per pound will be only
0.916 times as great. The product of
these two factors, 0.9609, shows that the
amount of refrigeration required to cool
a given quantity of worl of 12 per cent.

T.-VBLE a. PRODUCTS OF .SPECIFIC GR.W-

ITY AND SPECIFIC HE.\T OF V.'ORT

OF DIFFERENT PER CENT.

.STRE\GTH.S

Strength

Product

Strength

Product

8

0.9742

15

0.9499

9

0 9741

16

0.9463

10

0 9665

17

0.9426

11

0 9631

18

0.9390

12

0 9609

19

0.9353

13

0,9571

20

0.9320

14

0 9536

Refrigeration required to cool wort = that
required to cool equal quantity of water, multi-
phed b.v the above "product" corresponding
to strength of wort

grees, or, in fact, any number of pounds
through a range of temperature that will
give a product 20,000 pound-degrees,
just 20,000 B.t.u. will be required for
the cooling.

One United States gallon of water
at 62 degrees Fahrenheit weighs 8.336
pounds. The cooling of 20,000 gallon-
degrees will accordingly require

8.336 X 20,000 = 166,720 B.t.u.
If the cooling is accomplished in 24
hours the amount of refrigeration re-
quired will be

166,720 ^ 288,000 = 0.5789 ton
If done in one hour the equivalent rate
per 24 hours will be 24 limes as great,
or

0.5789 X 24 = 13.893 ions

Table 1 shows the amount of refrigera-
tion required to cool 1000 gallons of
water per minute, hour and 24 hours
through different ranges of temperature.
If 1000 gallons of water be cooled 50
degrees in one hoar the equivalent cool-
ing effect per 24 hours will be 10 times
the value given in the table for 5 de-
grees or 34.733 tons; if 53 degrees, 10
times the value for 5, or 34.733, plus

Wort Cooling
Table 2 shows the am.ount of refrigera-

Bbl. of \ / Gal. per \ /Wt. water

strength is 0.9609 times as great as for
the same quantity of water, or in the

Specific
of
049/^

/ Bbl. of \ / Gal. per \ /Wt. water\ / No.de- \/ Specific \/ Specific \ / R^'? of \
I wiirt per )( bbl. -wort: )( per gal.: )| grees F. )( gravity of )( heat of 1 | coolin*. \
Vhour: lOO/V 31 /\ 8.34 1b. / Vcooled: 40/ \wort: 1.049/ Vwort: 0,916/ _ I ^ons per I
(B.t.u. per hour equivalent to a ton of refrigeration per 24 hours: 12.000.) ~ \ "gj ^' /

tion expressed in tons per 24 hours re- above example of 100 barrels per hour,
quired to cool 100 barrels of water per 0.9609 X 86.18 = 82.80 tons

T.A.BLE 2. REFRIGER.\TION DUTY IN TONS PER 24 HOURS REQUIRED TO COOL
B.ARRELS OF W.\TER

Degrees

100 Bbl. of 31

1 Bbl. of 31

Degrees

100 Bbl. of 31

1 Bbl. of 31

Cooled

Gal., per Hour

Gal., per Min.

Cooled

Gal., per Hour

Gal., per Min.

1

2.1545

1 , 2927

21

45 . 2445

27,1467

4 3090

2.58.54

22

47.3990

28,4394

3

6.4635

3,8781

23

49 . 5535

29,7331

8.6180

5.1708

1 24

51.6988

31.0248

5

10,7725

6.1635

25

53.8625

32.3175

12.9270

7 . 7562

26

.56 , 1370

33.6102

7

15,0815

9.0489

27

58.1715

34 . 9029

1 7 , 2360

10.3416

28

60 , 3260

56.1956

9

19 3905

11.6343

29

62.4805

37 . 4883

21.59.50

12.9270

30

64 . 6350

38.7810

23 , 6995

14.2197

31

66 . 7895

39.0737

25 S494

15.5124

32

68.9440

41.3664

28 , 0685

16.8051

33

71.0985

42.6591

30. 1630

18.0978

34

73 . 0530

43.9518

32 3175

19.3903

35

75.4075

45.2445

16

34 , 4720

20.68.32

36

77. 5620

46.5372

17

36 5265

21 . 9759

37

79.7165

47.8299

38,7810

23.2686

38

SI. 8710

49.1226

40 9355

24.5613

; 39

83.9255

50.4153

20

43 0900

25. So 40

1 40

86 ISOO

51.6581

hour and one barrel per minute through
different ranges of tenioerature To ap-
ply this table to wort cooling multiply

The same result might have been ob-
tained from Table 1 by first reducing
the quantity in barrels to gallons, or di-

July 25, 1911

POWER

153

rect from the equation on page 152 in
which for clearness the previous values
have been substituted.

This expression when applied to wort
cooling expressed in barrels of 31 gal-
lons cooled per Wour becomes:
Tons — 0.021545 X U — <.) X s.g. X s.h.
in which

(/ — /,)= Range of temperature cooled
through (40 degrees Fahren-
heit) ;
s.g. = Specific gravity of the wort

(1.049);
s.h. = Specific hea* of the wort
(0.916>.
These values substituted in the above
equation ?ive tons per 24 hours equal
82.80 as above.

An Absorption Kink

By H. J. Macintire

The "old man" had been an operating
engineer for a number of years, and he
knew pumps and engines almost by heart,
but the company decided to utilize its
exhaust steam and make ice by the ab-
sorption method. From that time the
"old man's" troubles began. He was
nervous, and when things went wrong
he got excited; after the absorption plant
began to be operated he was excited most
of the time. How could that thing which
did not move do work? The compres-
sion machine was easy, for it was similar
to any compressor or a steam engine in
its operation, but the absorption machine
only had one. thing that moved, the steam
pump which pumped what they called
strong aqua from the r.'^sorber to the
large tank with steam coils which they
called the generator. He could not make
head or tail of the whole matter, and so
the day engineer put marks on the glass
gages and told the "old man" to keep
the levels constant at the marks. Oc-
casionally, however, he would still mix
things up a little.

The cooling water used necessitated
a galvanized-iron pipe for the coils, and
the zinc was dissolved out by the am-
monia; this formed a deposit on the gage
valves and tended to clog them. The
gage valves on the generator stuck dur-
ing the "old man's" watch, and when
he was relieved by the day man the gen-
erator was almost empty and the ab-
sorber was full to the top. The day man
then explained that it is not likely that
more than one valve will get choked up
at a time, and that the other gage glasses
will give a check on the generator. Any
unusual rise in the level of the liquid
the condenser or absorber should be
■ stigaled and the cause located,
'.age-cock valves may be cleaned while
rating by pushing back on the ball
■Tieans of a fine wire. The aqua will
•1 start out, removing the sediment
the velocity of flow, and the ball
-ill automatically close again.

LETTERS

Clearance in Compressors

I read the article by E. A. Murphy in
the June 27 issue of Power with interest.
I would like to know by what computa-
tions or actual comparative results Air.
Murphy arrives at the conclusion that a
compressor having a smaller clearance
would superheat the gas more than would
the same compressor with a larger clear-
ance, working under the same conditions
of suction and head pressures. It would
seem to me that the superheat in both
cases would be the same.

Mr. Murphy states that "the cylinder
walls of a no-clearance compressor will
superheat the gas more and thereby re-
duce the capacity to a greater extent than
will a compressor with clearance reduce
the apparent capacity," but fails to show
by comparative data, or a more detailed
explanation, the correctness of his state-
ment.

The apparent advantage of the practice
of ice-machine builders to reduce the
clearance to the minimum seems obvious.
If a compressor is working, say, against a
head pressure of 200 pounds, the suc-
tion pressure being 20 pounds, and
has a 5 per cent, clearance, the gas that
would remain in the clearance space, at
200 pounds, at the termination of the
stroke, would expand at the return stroke
and would, at one-quarter of the return
stroke, fill the cylinder with gas at 20
pounds pressure. Thus it may be seen
that this would apparently reduce the
working capacity of the compressor by
fully 25 per cent. Compressors with
larger or smaller clearances would re-
duce the working capacity in like pro-
portion.

To prevent this apparent loss of capa-
city, compressor builders are endeavoring
to reduce clearance space to the mini-
mum consistent with safety of operation.

One compressor builder accomplishes
this by injecting a charge of oil at every
stroke, in order primarily to lubricate
the compressor walls and secondarily to
fill the clearance space with oil at every
stroke to make the discharge of all the
gas in the compressor possible.

Another one builds compressors with
practically no clearance, using the dis-
charge-valve housing as a relief valve,
with an effective area equal to the bore
of the compressor, calling it a safety
head. This construction is used to pre-
vent serious damage to the machine in
case liquid should be drawn into the
compression space.

Compressors with small clearance are
at the present time generally conceded
to be the most economical, hut most of
us are willing to change our ideas on the
subject if Mr. Murphy can demonstrate
by actual results that his large clearance,
lower-superheat theory is correct.

Victor Bonn.

New York City.

Preventing Red Core in Ice

In 1885 I was assistant engineer in an
ice factory. The plant consisted of one
10- and one 5-ton Boyle machine and
for the three years that the plant was
operated there was not a block of ice
made with a red core, because the steam
cylinder was lubricated with beeswax in-
stead of oil. Although the one charcoal
filter on each machine could not take
out all the wax that came over with the
water, the small amount that was left
separated when the water was frozen
solid and floated to the top. The 1 '4 -inch
pipe carrying the distilled water from
the cooling coil to the charcoal filter was
about 50 feet long, and of common black
iron not galvanized. The storage tank
was galvanized, but the coil inside the
tank that carried the ammonia was not.
The iron pipes rusted, yet they caused
no red in the ice.

Three years later a 20-ton Consolidated
ice machine was installed with Corliss
valve gear. As the erector informed the
purchasers that wax would not lubricate
the steam valves, a dark-colored oil was
used, and in three months' time a red
core began to show in the ice and con-
tinued for many years. At times it was
so bad that it was necessary to chip 10
to 15 pounds out of the bottom of each
block, as it was unsalable.

To make ice free from a red core and
yet use oil for lubricating the steam
cylinder, the exhaust steam on its way to
the condenser must first pass through
a separator and then through a coke
filter. The coke should be renewed every
season. At the condenser the relief pipe
should blow slightly at all times, thus
getting rid of the uncondensable gases
and preventing air from being drawn in
if a slight vacuum should be formed.
The distilled water after leaving the cool-
ing coil should pass through a quartz
filter, the quartz to be in pea and nut
sizes laid alternately about 18 inches
thick. From the quartz filter the water
passes through a charcoal filter and then
to the storage tank. After running a
season the quartz should be taken out.
It will then be found to be oily and dis-
colored, especially the pieces nearest the
bottom, thus showing the work done in
separating the oil from the water. Char-
coal is useless for this purpose. Quattz
takes away the dull white appearance and
adds a bright sparkling look to the ice.

The quality of cylinder oil is a great
factor. I always use a clear oil rather
than a dark one, for even with all the
above precautions a slight discoloration
floats to the top of the" block. I have
examined blocks when nearly frozen and
seen these little particles slowly floating
up to the surface. They are so trifling
that the dip in the thawing tank dis-
lodges them.

E. Bronstorph.

Kingston, Jamaica, B. W. I.

POWER

July 25, 1911

"Addisto meter" Stroke Read-
ing Instrument

The quantity of water delivered by a
pump at each revolution varies accord-
ing to the length of the piston strokes.
To determine the length of all the strokes
of a piston of a pump is only a matter
of computing the cubic contents of the
liquid pumped during the time in which
such strokes are made. The "Addistom-
eter," or stroke-measuring device, re-
cords the length of each stroke of the
piston. It is shown in a sectional view
in Fig. 1. The roller ratchet arrange-
ment which is used is shown at A.

Fig. 2 shows the face of the instru-
ment, upon which the readings are re-
corded. Six figures are shown which in
pump work are usually all Ihat are nec-
essary; more may be supplied as the
case may demand.

The drum B, Fig. 1, is made exactly
1 foot in circumference and upon it
is wound a steel tape which is 0.004 inch
in thickness. This tape is attached di-
rectly to the piston rod or crosshead
of the pump, as in Fig. 3, and when the
crosshead has moved 1 foot the drum B
will have made one complete revolution
which is recorded on the unit counter-
wheel. Should it move 1 foot 1 inch, the
1 inch will be recorded on the small
dial beneath the counter as shown in
Fig. 2.

By the introduction of a bevel gear C D
and bevel pinion E it will be seen that
while drum B is revolving in a clockwise

Taction, by means of a roller cam shown
at A it will be seen that the shaft G is
made to revolve continuously in one di-

New Indicating Boiler Flow
Meter

The new FS-2 boiler flow meter, de-
veloped by the General Electric Company,
Schenectady, N. Y., and shown in Fig.
1, is designed to indicate the total amount
of steam generated at any instant by a
boiler or a battery of boilers in pounds
of steam per hour, or in boiler horse-
power. Therefore, it can be advanta-
geously used for obtaining data for
equalizing the load on individual boilers
or a battery of boilers; for determining

m^mmm^mm^,

Recorder Attached to a Pump

rection, thereby affording accurate regis-
try of the total feet travel of the parts to
which the meter is attached.

stoking efficiency, or correct feed-water
circulation ; for making known the effi-
ciencv loss due to the formation of

Fig. 1. Sectional View of the Stroke
Recording Instrument

Fig. 2. Showing Counters and Spring
Arrangement

direction, the drum F will be moving in This instrument may be readily at-

a counterclockwise direction. tached to pumps and elevators in vari-

As the drums are only engaged to the ous ways. It is manufactured by B. U.

shaft G while moving in a clockwise di- Potter, 45 Allyn street, Holyoke, Mass.

scale; for discovering internal leaks as
shown by the difference in water input
and steam output; and for indicating the
amount of steam distributed to the de»

July 25. 1911

POWER

155

partments of a manufacturing plant, or
used in manufacturing processes. In
other words, it is a valuable aid to engi-
neers and firemen in maintaining an in-
telligent oversight of the fire room.

The meter apparatus complete is com-
posed of a nozzle plug, the meter proper
and the necessary pipes for connecting
the nozzle plug to the meter.

The nozzle plug is similar to those
used with the steam-, air- and water-flow
meters made by this company and de-
scribed in ♦'-cse columns. It consists of
a screw plug, provided with a stem hav-
ing two sets of orifices, a leading set
arranged longitudinally and a trailing set
comprising three holes located at the
middle of the stem and at right angles

1. AU;TtR AND Piping

to the leading set. The interior of the
stem is divided longitudinally into two
separate compartments, the leading set
of orifices opening into one and the trail-
ing set into the other.

For operation the nozzle plug, which
is shown in Fig. 2, is screwed into a
small hole drilled and tapped in the
steam pipe, with the stem extending
across the pipe and the leading set of
orifices facing the direction of steam
flow. When thus arranged the velocity
of the steam causes a certain difference
of pressure in the two sets of orifices,
and this difference is communicated
through suitable pipes connecting the
compartments in the nozzle-plug stem
■with the U-tube of the meter.

The body of the meter is of iron cast-
ing cored out to form one leg and the
well of the U-tube, the other leg being
formed by one of the nozzle-plug con-
necting pipes entering the well at the op-
posite .Mid. The well is filled with mer-
cury, .md the rest of the apparatus,
including; the connecting pipes and the
compartments in the nozzle plug, is filled
with water.

The movable mechanism of the meter
comprises a smr.U float resting on top of
the mercury in one of the legs of the
U-tube, and attached to a waterproof
silken cord passing over a pulley and
held taut by a counterbalance weight act-
ing on the pulley in the opposite direc-
tion, and a pair of horseshoe magnets,
one inside the meter, fastened to the
pulley shaft, the other outside the meter
fixed to the pivoted end of the indicating
needle. The axes of rotation of the
two magnets are in line, ana their mutual
attractio.i exerted through a copper plug
screwed into the side of the meter-body
casting compels their, to move in unison.

When the difference of pressure in
the nozzle plug caused by the velocity of
the steam flowing in the steam pipe is
communicated to the two legs of the U-
tube, the mercury in the well rises or
falls in the leg containing the float to a
hight proportional to the difference of
pressure. The resulting motion of the
float rotates the pulley, and the motion
of the latter is transmitted through the
pair of magnets to the indicating needle.
The pair of magnets obviate the use of
the troublesome packed joint which

the nozzle plug. Its distance from the
nozzle plug is immaterial, though it
should be connected with '4 -inch iron
pipe of the required length. The best
location is on the front of the boilers
near the steam gage, in plain view- of the
fireman and the engineer.

The dial scale is 8 inches in diameter,
marked with heavy flow lines and large
figures on a white surface for easy read-
ing. A target of conspicuous size shows
a certain Row on the scale and can be
readily set from the outside.

The meter can be calibrated to read
in pounds per hour or in boiler horse-
power (30 pounds of steam per hour be-
ing taken as equivalent to one boiler
horsepower) for pressures ranging from
0 to 250 pounds gage; for quality rang-
ing from 4 per cent, moisture to 260
degrees Fahrenheit, superheat; and for
pipe diameters of 2, 3, 4, 6, S. 10, 12 and
14 inches. Meiers calibrated for pipes
of larger diameter can be furnished on
special order.

It should be noted in this connection
that for any given case a meter of this
t\pe is calibrated for a certain pressure,
quality and pipe diameter, and cannot be
used for anv other condition.

Transmis,sion Line Calculator

For calculating the line drop and en-
ergy loss in alternating-current circuits,
Robert W. Adams, 10 Hyde street, New-
ton Highlands, Mass., has placed on the
market an alternating-current transmis-
sion-line calculator.

LEADIN6 SET

Fic. 2. Nozzle Plug and Piping for Steam Flow Meter

would be necessary for transmitting the
motion of the pitlley inside the meter to
the indicating needle on the outside, by
means of any form of mechanical con-
nection.

The meter is easily irsfalled without
interfering with existing steam-pipe ar-
rangements. The work of installing is
simple, requiring the drilling and tapping
of a small hole in the steam pipe for the
insertion of the nozzie plug. The design
of the latter permits of its insertion in
pipes running cither vertically or hori-
zontally. Care should be taken, how-
ever, to select a straight run of pipe of
at least 12 pipe diameters in length. The
meter itself can be located in any de-
sired place, so long as it Is kept below

The calculator consists of a stationary
disk of opaque wiiite celluloid 4's inches
in diameter, and a revolving disk of
transparent celluloid 3,'.- inches in diam-
eter, eyeleted to the stationary disk
so as to turn easily upon it. These disks
arc printed with the necessary diagrams,
the stationary diagram in red and the
revolving diagram in black to permit
easy reading.

The ranges of the various scales are:
Load, from 10 to 20,000 kilovolt-am-
peres; voltage, from 1000 to 50,000;
power factor, from 10 to 100 per cent.;"
distance, from I to UK1 miles; conductor,
from No. 8 to No. OOOO Brown & Sharpe
copper; line drop, from 0 to 20 pcr-ccnt.;
frequency, 25 or 60 cycles.

156

POWER

July 25, 1911

The operation of the calculator is sim-
ple; it is only necessary tj make two
settings to obtain the final results. The
value K, which is obtained in the first
setting, is a transmission factor depend-
ing on the load, voltage and distance of
transmission. This factor is used direct-
ly in the second setting to determine the
line drop or ''regulation," which is de-
fined as the difference in voltage between
the two ends of the line expressed in
percentage of the receiver voitage. The
method of securing the result includes
in an accurate manner the effect of load
power factor, which is reversible. This
is of value where it is desired to obtain
the size of wire necessary lo produce a
given drop.

Complete directions are printed on the
back of the calculator, together with a
typical e.xample, and a person having no
technical training can quickly learn the
method in a few ir.inutes. No book of
rules, auxiliary tables or data of any
kind are required, which features of the

slide rule for solvmg problems in multi-
plication and division.

The calculator is based on the use of
annealed copper wire at 20 degrees
Centigrade (68 degrees Fahrenheit) or
hard-drawn copper wire at 15 degrees
Centigrade (59 degrees Fahrenheit), and
on three- wire three-phase and four-wire
two-phase circuits. Single-phase circuits
can be calculated as easily as three-
phase, although the device is primarily
designed for three-phase circuits as be-
ing the most common for transmission
work. The diagrams are based on a
spacing of 18 inches between wires and
are sufficiently correct for all practical
work on circuits varying from 6-inch
to 36-inch spacing.

F'errocliem for Feed Water

Treatment

The treatment of boiler-feed water by
electrochemical-mechanical means is not
entirely new. A process developed abroad

Transmission Line Calclil.mor

device add greatly tn its convenience and
make it adapted for use in the field.

Upon the back of the stationary disk
is also printed a convenient reference
table giving the weights and costs of
bare and triple-braid weatherproof cop-
per wire per mile of two-, three- and
four-wire circuits.

Another advantage is that the two
lower revolving scales ordinarily repre-
senting distance and transmission fac-
tor can also be used as an emergency

and recently exploited in this country
employs a set of perforated aluminum
plates over which the water is made to
run in a thin stream. The best results
are said to be obtained when the plates
are exposed to strong sun rays.

The very latest thing in this line is
being put out under the patent name of
Ferrochem by the Ferrochem Company,
Bradbury building, Los Angeles. It does
not need the aid of Old Sol. Just be-
fore entering the boiler the feed water

is made to swirl through a cast-iron com-
partment which has an irregular contour
and a sectional area two or three times
as great as the feed pipe itself.

A nozzle at the inlet of this compart-
ment of smaller diameter than the feed
pipe causes the water to enter at a
rather high velocity and circulate briskly
in the compartment. A number of metal
balls, usually three, swash around in the
water within the compartment.

It is these balls that are the spe-
cial feature of the apparatus. The
balls are composed for the most part
of chemically pure iron, it is said. The
balance of their composition is made up
of a number of other metallic elements.
As the balls wallow around over the
rough irregular interior surface of the
casting, minute flakes are rubbed off and
diffused through the water, and it is said
that the scale-forming impurities com-
bine, or react or do something or other
with these little flakes so that when they
enter the boiler no scale whatever is
formed and only a sand-like sediment is
discovered when the boiler is opened for
cleaning.

Not only is this Ferrochem system said
to prevent scale from forming but it is
also claimed that it reduces scale which
has already formed in the boiler.

The company was not overexplicit in
describing its apparatus to the writer
because all of its patent claims had not

One For.m of Ferroche.m Feed-water
Treating Machine

been allowed at the time of his inter\iew.
They did, however, refer him to a place in
which the device had been employed for
several months apparently with success.
No stock in the company is being of-
fered to the public.

Jefferson I nion Elbow

Tlie accompanying illustration shows

the design of elbow just got out by the

Jefferson Union Company, 161 Main

street, Lexington. Mass. It is made both

Jefferson Union Elbow

male and female. The general construction
is the same as that of the other types
of union joints manufactured by this firm.

July 25, 1911

POWER

157

Improved Detroit Automatic ^"'^ ^^ "^^ cooling surface is large and as

Q 1 air is admitted under the coking coal

OtOKer (j^g [jfg gf ji^g grates is prolonged.

In the December 29, 1908, issue of The clinker crusher. Fig. 3, is com-

PowER, the Detroit automatic stoker was posed of a row of heavy cast-iron disks,

which rotate alternately toward and from
each other and crush the clinkers and
deposit them in the ashpit below.

The crusher is operated by means of
the bell crank connected to the operating
bar in front.

The motion of the crushers may be
regulated to suit the quantity of ash and
clinkers found, in the fuel.

The stokers shown in Fig. 4 are ar-
ranged for a battery of two boilers. They

Fig. 1. Showing Double Arch and Rear View of the Reciprocating Feed

Fig. 2. Vibrating and Stationary
Grates

can be installed with flush front or with
extension front, and may be applied to
either large or small boilers of all types.
Coal can he shoveled in by hand or sup-
plied from overhead bunkers.

described and the worm conveyer, or
screw feed, and the reciprocating or
pusher feed were introduced. The im-
provements made since are illustrated
and described herewith.

In Fig. I are shown the double-arch
construction, which is still retained, and
a rear view of the reciprocating feed.
Air, admitted through the front, is heated
between the arches and passes through
the sectional arch supports into the fur-
nace, directly over the coking coal as it
enters at the upper end of the grate
on both sides of the furnace.

The pusher boxes are operated with a
shaft extending through the front and
connected with removable links to the
operating bar.

Each alternating grate is operated by
the driving bar in front, and may be dis-
connected when a noncoking or free-
burning coal is used.

The movement of the vibrating grates
prevents the clinkers from forming on
the grates, and at the same time moves
the bed of fire down toward the center
of the furnace.

If the coal is to be shoveled into the
magazines by hand through the front, the
movable slides in the top may be closed.

The grates shown in Fig. 2 are of two
kinds, vibrating and stationary. The
movement of the vibrating grate between
the stationary grates eliminates the ne-
cessity of poking the fires.

As each grate is independent of each
other, their removal is an easy matter,

Fig. 3. Clinker Crusher

Fig. 4. Front of Stoker as Arranged for Two Bon ers

158

POWER

July 25, 1911

openings are provided with steel covers
which are easily removable, and all
valves are readily accessible for inspec-
tion or repairs.

Each upper water chamber supports
an A-frame, of box section, which forms

Fig. 5. Stoker Arranged to be Fed by Gravity

Fig. 5 is an illustration of an installa-
tion of these stokers. Coal is fed by
gravity from the bunkers located on top
of the stokers.

This stoker is made by the Detroit
Stoker Company, Detroit, Mich.

Hamilton Series "N" Power
Pump

A design of power pump, built by the
Hooven, Owens, Rentschler Company,
Hamilton, O., is illustrated in Fig. 1.
This pump is built duplex, double-act-
ing, and the general design comprises
two pairs of horizontal water chambers,
each pair connected at each end by ver-
tical water passages, and at the center
by a vertical working barrel or cylinder,
as shown in the sectional view. Fig. 2.
The upper water chambers of each pair
are connected at each end by arms firmly
bolted together in a vertical plane, pass-
ing lengthwise through the center of the
pump. In each arm there is an intake
or discharge opening where a gate valve
can be placed. Ry referring to Fig. 1
it will be seen that by closing one pair
of gate valves, ore intake and one dis-
charge, the water cannot flow from one
pair of chambers to the other, at either
end, thus making it convenient to use
one side or one-half the pump without
using the other hn'f. When inspection
is desired, or repairs are necessary, the
entire service of the pump is not im-
paired, which is an important feature.

Each water chamber carries two sets
of valves, an intake and a discharge set,
one on each side of the vertical cylinder.
The valve decks proper are cast as parts
of the water chaii:ber, but each deck

carries one bronze plate, to which are at-
tached all the valves in that section of
the chamber, or that quarter of the pump,
regarded as a unit. AU valves seat on
horizontal bronze plates. When these
plates are worn, they can be resurfaced.

Fic. 2. Section through Ha.milton
Pump

suitable air chambers for both intake and
discharge ends. These A-frames are
provided with bored guides for the cross-
head and journals ;'or the shaft with its
disk cranks and pulley. The plunger
is grooved, and fits closely in the cylin-
der, thus reducing the leakage of the
water to a minimum. No air can enter
the pump chambers by reason of defec-
tive plunger packing.

Air Cylinder for Piston Pump

The Goulds Manufacturing Company,
Seneca Falls, N. Y., is placing on the
market a special air cylinder for attach-
ing to sizes 3x5 and 4x5 inch of the

FiG. 1. Hamilton Series N Pots-er Pump

or easily exchanged for new ones. The
advantage of this valve construction is
that all valves open vertically, and the
springs act perfectly, thus assuring a
quiet running pump. The valve-chamber

Aar Cylinder Attached to Goulds
Piston Pump

July 25, 1911

Pyramid double-acting piston pump when
used for pneumatic water-system pump-
ing.

This air cylinder does away with the
necessity of a separate pump for main-
taining the required air pressure in
pneumatic tank systems. It is designed
to operate against a pressure of 75
pounds. Opening the air cock prevents

I the air from going into the tank and re-
lieves the pump of all pressure when
not required. The suction and discharge
valves and the cylinder are of brass. The
plunger is packed with leather cups and
is operated by the piston rod of the
pump. The cylinder bracket is held in
place by the same bolts that hold the
cylinder head. The pipe leading from

i the air attachment is connected to the
drain-plug opening or discharge chamber
of the pump. The attachment is shown
in the accompanying illustration.

Flywheel E.\plosion at West
Berlin, Mass.
By J. W. Parker

On July 4 an accident caused by the
overspeeding of one of the engines oc-
curred at the power station of the Wor-
cester Consolidated Street Railway Com-
pany at West Berlin, Mass.

The plant consists of four horizontal
return-tubular boilers which carry a gage
pressure of 120 pounds, also two hori-
zontal engines, 20x42 inches, of the Cor-
liss type. On each the belt wheel is 16
feet in diameter and the width of the rim
is 28' 2 inches. The engines are run
condensing at 88 revolutions per minute
and are belted to direct-current gen-
erators of about 200 kilowatts capacity.

Due to the overspeeding of one of the
engines, the flywheel exploded, com-
pletely wrecking the generator to which
the engine was belted. One piece of the
rim, about 7 feet long, and probably
weighing upward of a ton, was hurled
through the roof of the building and
landed about 400 feet away on one of
the New York, New Haven & Hartford
lines, breaking off in its flight a large
limb of a tree. The jaw of the main
bearing was broken off the engine bed
and the main shaft together with the
bent connecting rod still attached to the
crank pin, also the crosshead and piston
rod (which had pulled out of the pis-
ton, leaving it and the piston-rod nut in
the cylinder) were thrown over to the
wheel side of the bed and through the
floor endwise. The outboard bearing was
torn from its bed and thrown through
the brick wall of the building. The wrist-
plate stud was broken off. also the ec-
centric connection and various parts of
the valve motion.

Fortunately, none of the main steam
connections was broken, although a
piece of the belt wheel landed on fop
of one of the boilers and broke the lever
of one of the pop safety valves.

POWER

Both engines were running when the
accident occurred and the flying pieces
from the wrecked engine and generator
knocked the brush attachment off the
generator driven by the other engine and
put it out of commission. This left the
station in darkness and the engineer, in
groping about in the darkness to find
the throttle valve and shut off the steam,
fell through a hole broken through the
floor and fractured one of his arms.

The armature windings were torn loose
and in a tangled mess radiated from the
center of the shaft. Pieces of the gen-
erator pulley were lying about the floor,
something heavy having struck the wheel
with such force as to bend the shaft
and turn the entire machine more than
a quarter of the way around from its
original position.

The governor of the duplicate engine
is belted from the bare shaft of the en-
gine. Consequently, the governor pul-
ley is of small diameter. The governor
pulleys on both engines were not pro-
vided with flanges to prevent the gov-
ernor belt from running off. The safety-
stop device is arranged with a small
flanged pulley riding on the governor
belt, which in the event of the belt
breaking or running off is intended to
drop and through connecting mechanism
prevent the latches of the steam valves
engaging and thus stop the engine. Evi-
dently the safety device failed to work
and the wreck resulted.

Massachusetts N. A. S. E.
State Convention

The sixteenth annual Massachusetts
State convention of the National Associa-
tion of Stationary Engineers was held at
Worcester, July 13, 14 and 15, with
headquarters at the Bay State hotel.

The business of the convention was
conducted in the Mechanics building.
The committee is to be congratulated for
its wise selection of this hall, which was
situated almost adjacent to the head-
quarters.

There was the usual large attendance
of delegates, and the meetings were held
in Washburn hall on the main floor of
the building.

The spacious auditorium on the sec-
ond floor was conveniently arranged and
neatly decorated for the use of the sup-
plymen for their mechanical display. The
exhibit was opened to the public on
Thursday morning, and was liberally
patronized.

The convention was formally opened
on Friday iriorning at 10 o'clock. A. G.
Lamb, chairman of the con\<cntion com-
mittee, called the meeting to order and
introduced Mayor James Logan wh"
warmly welcomed the delegates and
guests to Worcester. Past National Presi-
dent Herbert E. Stone responded for the
engineers. Edward M. Woodward, presi-
dent of the board of trade; Fred L. John-

159

son, of Power; Mrs. Nella C. Moore,
president of the ladies' auxiliary of the
New England States, and National Vice-
president Edward H. Kearney also made
interesting addresses. At the close of
these ceremonies. State President George
L. Finch took charge of the meeting, and
upon taking the chair was presented a
silver-mounted gavel, made from wood
grown in the heart of the Bay State, the
gift of the members of the State body.
After his speech of acceptance, Mr. Finch
appointed the necessary committees,
when an adjournment was taken until 2
p.m.

At the afternoon session a committee
of five was appointed to confer with
the members of the other New England
associations regarding the advisability of
forming a New England District Associa-
tion. The delegates were quite enthusiastic
in this movement, as it would give the
larger bodies in Massachusetts and Con-
necticut an opportunity to assist the
weaker associations in Maine, New
Hampshire, Vermont and Rhode Island.

It was decided to hold the next annual
convention at Northampton.

The final business of the convention
was the election of State officers, which
resulted as follows: James H, Sumner,
president, of Cambridge; J. T. Maloney,
vice-president, of Fall River; Ole B.
Peterson, secretary, of Boston; Walter
B. Damon, treasurer, of Springfield; Al-
mond F. Cheney, conductor, of Milford;
John H. Parker, doorkeeper, New Bed-
ford. Charles J. Wilder, of Worcester,
after a close contest was chosen as State
deputy.

The supplymen held a mectmg on Fri-
day afternoon, and, following the lead of
the delegates, formed what will be known
as the New England Commercial Engi-
neers' Association, for which the follow-
ing officers were elected: Claude Allen,
president, of Garlock Packing Company;
H. B. Aller, vice-president. Manning,
.Maxwell & Moore; Edward F. de Grouchy,
secretary. New England Engineer; Her-
bert E. Stone, treasurer, Elliott Com-
pany.

The following comprise the board of
directors: Thomas Burke, Burke Engi-
neering Company; Gordon Hall, Enter-
prise Rubber Company; T. A. Collins,
Philadelphia Grease Manufacturing Com-
pany; W. W. Beal, Lunkcnheimer Com-
pany.

Therr were several features of enter-
tainment.

On the evening of July 13 the engi-
neers were entertained by the supplymen
in the grill room of the Bay State hotel.
Songs, stories and recitals were inter-
spersed with addresses. F. E. Ransley
presided. Refreshments were served.

Visits were made to the Worcester
Polytechnic Institute and to the Worcester
School of Trades on Saturday morning.

On Friday evening a smoker was
tendered to the engineers by the supply-

160

men, at Washburn hall. There was a
most interesting and varied program of
entertainment. Hardy's orchestra opened
with musical selections; William F. Prizer,
Vacuum Oil Company, sang baritone
solos; W. E. Percy, of Worcester As-
sociation No. 4, told stories and recited;
Joe McKenna, of Jenkins Brothers,
sang popular songs; Jim Devins,
of the Peerless Rubber Manufacturing
Company, told laughable stories; Billy
Murray, of Jenkins Brothers, rendered
several uptodate ditties, and Jack Armour,
of Power, closed the evening's fun with
stories, etc. Between the acts National
Vice-President Kearney presented Past
State President Finch a signet ring and
a silver service, from the members
of the State organization and sup-
plymen. Mr. Kearney also distributed
the educational prizes for the 1910-
1911 contest to the members of
Worcester No. 4, as follows: A. C. Luft,
first prize; C. G. Bergland, second, and
James Hickey, third prize. The prizes
were valuable and appropriate. The A. W.
Chesterton Company had a drawing for
a handsome gold watch, which was won
by W. A. Edmundson. The Aschroft
Manufacturing Company presented a
steam-engine indicator, which was drawn
for and was won by M. H. Bolton, of
Worcester Association No. 4.

At twelve o'clock on Saturday after-
noon, special cars carried the company
to Fern Grove, Lake park, where a light
lunch was partaken of, after which the
annual baseball match between the en-
gineers and supplymen took place, result-
in a victory for the engineers by the
score 15 to 11. This being the third
consecutive year that the engineers have
been victorious, they have therefore won
permanently the pennant.

At the close of the ball game the
steamer was taken for a sail across the
lake to White City, where an appetizing
banquet was served. Outdoor amuse-
ments brought the pleasant day and the
convention to a r.ose.

The Ladies' Auxiliary convened at the
Warren hotel on Friday and Saturday
and transacted considerable important
business.

About eighty fimis had exhibits as fol-
lows:

Ackley & Brink Manufacturing Com-
pany, Albany Lubricating Company,
American Metal Hose Company, Ameri-
can Oil Company, American Steam Gauge
and Valve Manufacturing Company,
George P. Anderson, Ashton Valve Com-
pany, Autogenous Welding Equipment
Company, Bishop & Babcock Company,
J. Henry Blanchard, Braman-Dow Com-
pany, Builders' Iron Foundry, Burke En-
gineering Company, Central Supply Com-
pany, A. W. Chesterton Company, Charles
A. Claflin & Co., Cling-Surface Com-
pany, Coates Clipper Manufacturing
Company; Connecticut Boiler Cleaner
Company, Crandall Packing Company,

P O W E R

M. T. Davidson Company, Dearborn Drug
and Chemical Works, E. Dugar, Eagle
Oil and Supply Company, Economy In-
strument Company, Economy Lubricat-
ing Company, Elliott Company, Enter-
prise Rubber Company, G. L. Fairbanks
& Son, Federal Metallic Packing Com-
pany, Garlock Packing Company, Gra-
ton & Knight Manufacturing Company,
Greene, Tweed & Co., Hart Packing Com-
pany, Hartford Mill Supply Company.
HiUs-McCanna Company, Hinckley &
Ramsay, Hudson Belting Company, W. J.
Hyland Manufacturing Company, Home
Rubber Company, Ironworks Company,
Jenkins Brothers, H. W. Johns-Manville
Company, Keystone Lubricating Com-
pany, George W. Knowlton Rubber Com-
pany. Lagonda Manufacturing Company,
Lubron Company, Lunkenheimer Com-
pany, Mason Regulator Company, Man-
ning, Maxwell & Moore, Massachusetts
School of Engineering, Max Machine
Company, McLeod & Henry Company,
Monarch Valve and Manufacturing Com-
pany, National Engineer, Nelson & Shat-
tuck. New England Engineer, Nightingale
& Childs, Peerless Rubber Manufactur-
ing Company, Perfection Crate Com-
pany, Patterson Lubricating Company,
William Powell Company, Power, Prac-
tical Engineer, Philadelphia Grease Man-
ufacturing Company, Quaker City Rubber
Company, Reynolds Oil Company, P. L.
Rider Rubber Company, Walter C. Rug-
gles Company, Southern Engineer,
Strong, Carlisle & Hammond Company,
Tillotson Humidifier Company, Universal
Lubricator Company, Vacuum Oil Com-
pany, Washburn & Garfield Manufac-
turing Company, L. J. Wing Manufactur-
ing Company, W. R. Winn.

Boiler Manufacturers' Con-
vention at Boston

The twenty-third annual convention of
the American Boiler Manufacturers' As-
sociation was held at the Hotel Bruns-
wick, Boston, Mass., July 10 to 13. The
association was welcomed to the city by
Walter L. Collins, acting mayor, w-hose
greeting was accepted in behalf of the
association by President E. D. Meier.

The meeting was fairly well attended,
and, although no formal papers had been
prepared, ample material for discussion
and consideration was found in the re-
ports of the various committees and in
the topical questions submitted by the
committee on data.

Suitable resolutions were passed to the
memory of James Lapham, one of the
founders of the organization whose death
occurred since the last meeting, and H. J.
Hartley, of Philadelphia, another of its
founders, was made an honorary- member.
The entire board of officers was re-
elected with the exception of M. A. Ryan
as fifth vice-president. Mr. Ryan's com-
pany having withdrawn, M. H. Broderick,

July 25, 1911

of Muncie, Ind.. was elected to this of-
fice. E. D. Meier, of New York, con-
tinues as president and J. D. Farasey,
of Cleveland, O.. secretary. The next
meeting will be held in New Orleans.

The social features connected with the
convention consisted of an informal re-
ception at the Brunswick on Monday
evening; an automobile trip for the ladies
on Tuesday and on Tuesday evening a
visit to Norunbega park; on Wednesday
afternoon and evening a trip to Nan-
tasket beach, with a shore dinner at the
Palm gardens. Paragon park; on Thurs-
day morning an automobile trip to points
of historic interest in and about the city,
and on Thursday evening a banquet.

The committee reports and discussions
will be available for a later issue.

First Annual Convention
of Institute

The first annual convention of the In-
stitute of Operating Engineers will be
held in New York City, Friday, Saturday
and Sunday, September 1, 2 and 3. The
sessions of the convention will be held
in the Engineering Societies building, 29
West Thirty-ninth street. New York City,
and much business of importance will
be transacted in the way of adopting
the constitution, bylaws, educational re-
quirements, apprenticeship requirements,
regular study courses, lists of books,
etc. The first day's session will consist
of addresses by prominent speakers, the
appointment of committees and allotting
of work to them.- The second day's ses-
sion will be taken up with the executive
business of the institute. The third day's
session will be given over to sightseeing.
Special rates will be provided for all
those who attend the convention. All
those who expect to attend this conven-
tion are requested to write at once and
notify Secretary Hubert E. Collins, 29
West Thirty-ninth street. New York City.

PERSONAL

H. T. Fryant has resigned from his
position with the Mechanical Rubber
Company, which he has held for the past
five years, and has opened an engineering
office in Jackson, Miss. He will be in a
position to do indicator work and conduct
a general-repair business.

R. H. Fenkhausen, who for the past
six years has been chief electrician at
the Risdon Iron and Locomotive Works,
on July 1 entered the service of the
Union Iron Works Company, of San
Francisco, as electrical engineer. Mr.
Fenkhausen is well known to our read-
ers as the author of some of the best
practical articles on electrical engineer-
ing that have ever appeared in Power.

lu

\q\. .U

M;\\- YORK, AUCJUST 1, 1911

No. 5

IX all probability, Chief, there is in your plant
a young man in a black shirt and greasy over-
alls, a dark smudge under one eye, his arms cov-
ered with dirty oil to the elbows. Perhaps his eyes
are snapping with the pleasure of his first association
with machinery.

He had always longed for the time when he could
"get close to the wheels"; as a little kid he hung
aroimd the power-house door, and nothing short of
turning the hose on him could drive the boy away.

And now his boyish dream has come triie; he is
one of " the men."

What are you going to do for him. Chief? Will
you hark back to the days when you were a kid? Will
you put yourself in his place and take him in hand
and give him the benefit of your own dearly bought
experience? Do you in-
tend to keep a watchful eye
upon him and guide the
boy in the path from which,
perhaps through neglect, you
many times strayed? Will
you so instruct him in his
duties and exercise a firm,
kind discipline over him that
in the days to come he will
rise to hights where he may
be a credit to his instructor
and an honor to his calling?

He is now an unknown quan-
tity— the algebraic x. In the
future the young man may be

"Ur jnanager or your super-

iiiendent; nobody kno'vs.

Will he then have good reason to give you a warm
grasp of the hand and say he has not forgotten what
he owes to his old chief for the thorough training and
kind words of counsel? This would be something
of which to be proud.

So very much depends upon starting this young man
properly. If he is made of the right stuff, he will
early reflect credit ujion you, and you will be given
credit for having set him upon the right track.

Times have changed from the days when roughness
and severity "ruled the roost"; when a man to suc-
ceed had to fight every inch of the way if he would
rise above the disgruntled, the sloths, the plodders.

To brnig out and devclo]) the best that is in him,
the young man of today nmst see an intelligent reason
for what he is assigned to do, and you should be his
instructor, Chief.

Do not discourage and
dishearten him by neglect
and undue severity. It is
verj' true that a power plant
is no nurserj' where the young
man must be petted and cod-
dled ; it is a school wherein
the student is expected to
Icam and iirofit by what he
has been taught; to under-
stand that he owes a duty to
hi*; chief and to his employers,
and must render full value to
tliem.

It is up to yoti ; will you
lu'li) liim^

162

POWER

August 1, 1911

Richmond's New Municipal Plant

For many years the city of Richmond,
Va., has purchased electrical energy for
street lighting from a private corpora-
tion. Of late there have been about 1000
arc lights, which have cost the city $56
each, making a $56,000 lighting item.

Another problem which came up for
consideration was that of the city's water
supply. As suburban districts had built
up along the river in the direction of the
water supply, the city's needs outgrew'
the capacity of the old pumping station,
and a new one was built some eight

By Edwaru T. Binns

Xeu- hydroelectric plant
with 20-foot head to supply
arc lighting and motors in
pumping station. Auxil-
iary steam turbine plant
installed as a reserve.

Fig. 1. Generating Room of Rich.mond Plant

miles up the James river. It was equipped
with motor-driven centrifugal pumps
capable of delivering some 20,000,000
gallons, or an increase of nearly 50 per
cent, over the old station.

One of the objects of erecting the
new municipal plant, which is now Hear-
ing completion, was to furnish energy
for the new pumping station.

The dam for the water supply extends
from the north shore for nearly a mile
in a diagonal direction to the old Bell
Isle prison island.

The new station will use water power,
and the accompanying photographs will
serve to convey an idea of the dam,
breastwork, gates and flume for bring-
ing the water to the wheels. The in-
take gates were fitted up by the Colvill
& Willcox Company.

The development provides for a 20-
foot head. Three 5-foot Morgan-Smith
low-head wheels have been installed and
arrangements are being made for a
fourth. Lombard governors regulate the
speed within 3 per cent, variation. The
gates in the draft tubes are of the wicket
type and are operated by the governors
through a train of gears. They are pro-
vided with dashpot relay attachments to
guard against overrunning.

General Electric 60-cycle generators
are direct connected to the waterwheels.
They are of the revolving-field type and
have a capacity of 425 kilovolt-amperes
at 150 revolutions per minute. Two
motor-driven exciters furnish direct cur-
rent at 125 volts for field excitation. The
motors in the pumping station are of the
induction type and use alternating cur-
rent at 4000 volts.

Fig. 2. Dam, Breast Gates and Flu.me

August I. 191 1

I'o provide for possible emergency,
steam equipment has been installed suffi-
cient to take care of the station load.
The boiler room contains two 500-horse-
power Babcock & Wilcox boilers with
the usual boiler-room auxiliaries. There
are two Curtis turbines of the vertical

POWER

The switchboard presents an attractive
appearance. It is composed of 32 panels
of blue Vermont marble mounted upon a
framework of piping. Upon the five
generator panels are mounted the usual
complement of horizontal edgewise and
Thomson meters. The field rheostats are

163

wiring system is arranged on the three-
phase, four-wire plan. The busbars are
in duplicate and all oil switches are of
the double-throw, double-pole type, and
are so arranged that any generator or

Fic. 3. Boiler Roo.m of Au.xiliary Steam Plant

type direct connected to revolving-field
alternators running 1800 revolutions per
minute. The condensing outfit consists
of two Alberger barometric condensers
placed outside the building and pro-

mounted directly above the panels and
are plainly visible in the view of the
switchboard. The two three-phase feeder
panels which control the four 150-
horsepower motors at the pumping sta-

ple. 4. Albfrger Barometric Con-
densers

feeder may be thrown on either bus.

Each feeder panel has connection
through a 100-light General Electric
transformer.

Although nn figures are available, it

Fig.

S-iiTCiiuoAki. oi ^2 1'

r

Kac.K nl

vided with both clrculatinn; pumps and
a siphoning attachment from the sta-
tion supply in the forebay. The di7-vac-
uum pumps are of Laidlaw-Dunn-Gor-
don make.

tion are shown in the picture as nearest
the observer.

Eleven panels make up the arc board
which is equipped with oil and open
and short-circuiting plug switches. The

has been slated that the new plant will
supply the arc lights and the motors in
the new pumping station at an annual
expense considerably less than the cost
of running the old pumping station.

164

POWER

August I, 1911

Determining the Value of a B. T. U.

Heat may be measured in two ways:
by the use of a definite quantity of heat
as a unit, or by measuring the amount
of mechanical worl< to which it is equiva-
lent. Prior to the nineteenth century
heat was generally believed to be an
invisible material which bodies soaked
up, just as a sponge would take up water.
It was not known that heat was con-
vertible into work or work into heat ac-
cording to a definite law. Toward the
end of the eighteenth century, however,
Rumford denied the materiality of heat.
He reasoned that if it were a material
it might be entirely removed from a
body as all the water may be squeezed
from a sponge, and if this were not the
case the material theory would fail. He
rubbed together two pieces of iron under
water, the temperature of which he meas-
ured, and observed that as long as the
rubbing was continued, heat was gen-
erated. It followed that, as the heat was
produced by motion which required en-
ergy, it must be a form of energy and
perhaps motion. Between 1800 and 1840
this theory gained ground until, in 1842,
Mayer and Joule separately established
the fact that heat had a definite value in
terms of work and that the one could
be transformed into the other. Since
then the so called "kinetic" theory of
heat has slowly developed and is now
generally accepted.

This theory states that heat is a mani-
festation of the molecular motion of mat-
ter and that heat and mechanical energy
are identical.

Although the early physicists were un-
certain as to the nature of heat, they
knew that to measure it intelligently,
three conceptions were necessary, name-
ly, those of mass, temperature and heat
capacity. Thus, a pound of iron at 100
degrees would raise the temperature of
a quart of water more than the same
weight of iron at 200 degrees would a
bucketful of water. More heat was added
to the bucketful, but the temperature
rise was less because the amount of
water heated was greater. It was recog-
nized that a large amount of a substance
at a low temperature may contain more
heat than a small amount of the same
material at a high temperature. Tem-
perature was found to be a measure of
heat intensity which, taken with the
mass, fi.\ed the quantity of heat; just
as voltage is a measure of current in-
tensity and, taken with amperage, deter-
mines the electrical energy.

As a natural development, the heat of
a body was measured hy noting its ef-
fect upon the temperature of a known
mass of another material, water being
the standard for comparison. A rough
unit then was the amount of heat re-
quired to raise the temperature of a
unit mass of water one degree.

By Julian C. Smallwood*

The fi-^ing of a standard
Ileal iDiil and a restime of
llic wpyk of various investi-
gators in determining the
mechanical equivalent of a
British thermal unit.

Experiments showed that the amount
of heat corresponding to a rise of one
degree in the temperature of a unit mass
was different for different substances.
This led to the conception of "specific
heat." It was found that this quantity
was different not only for different ma-
terials, but for the same material it
varied slightly with the temperature;
this applied especially to water.

From the foregoing it will be seen that,
for a definite heat measure, a standard

D| 7C

Temperature, Degrees '•-

Fig. 1. Relation between Linear
pansion and temperature

unit of mass, a standard unit of tem-
perature and a material at a standard
specific heat are necessary.

The English unit is a mass whose
weight is one pound. This is based upon
a copy of the standard kilogram of the
archives of France. Upon the legaliza-
tion of the metric system in the United
States in 1860 the pound was defined
by act of Congress as the relation,

2.2046 pounds = 1 kilogram
This made the kilogram the fundamental
standard, following the practice of other
countries which had previously adopted
the metric system. It was later found
that the relation

2.204622 pounds = 1 kilogram
was more accurate and this is now taken
as the standard.

Regarding the unit of temperature, the
standard, although definitely fixed, is not

so well established. It was early found
that as materials were heated they in-
creased in volume. It appeared also, in
most instances, that such expansion was
uniform for equal additions of heat.
Hence, the natural conclusion was that
the increase in the length of a material
was a measure of heat intensity. Accord-
ingly, the mercury thermometer was de-
vised, mercury being chosen on account
of its expansive qualities. The Fahren-
heit scale of degrees was chosen in a
roundabout way by its inventor who ex-
posed his thermometer first to freezing
water and then to water at the boiling
point. He marked the stem of the in-
strument at the level of the mercury in
each case, and divided the distance be-
tween the marks into 180 equal parts.
Each part he called a degree and then
continued the scale below the freezing
point by 32 of these divisions. The
freezing point thus became 32 degrees
and the boiling point 212 degrees. There-
fore, the Fahrenheit degree may be de-
fined roughly as the increase in tempera-
ture corresponding to 1 180 of the total
linear expansion of the material chosen
for a thermometer, between the freezing
and boiling points of water.

In a thermometer whose material ex-
pands uniformly with an increase of
temperature, the relation between linear
expansion and actual temperature in de-
grees would be as shown by the straight
line A B C in Fig. 1. The distance Y
would then correspond to 1/180 of the
temperature between 32 and 212 degrees,
as shown by X. A thermometer whose
material does not expand uniformly
would follow, some relation such as
shown by the curve AFC. The two in-
struments would record the same at the
freezing and boiling points, and they
would each have 180 equal divisions
called degrees; but any one of these
divisions, as V, on the scale A F C, would
correspond to an actual temperature A",
as compared with .V and the scale ABC.

No known material expands according
to the ideal relation shown by the line
ABC. The departure from it, although
slight, is appreciable in accurate work.
Also, different materials expand accord-
ing to different laws. If. however, the
linear expansion of a particular material,
such as mercury, were alone the measure
of tem.perature it would yield a definite
though arbitrary, scale, because the ex-
pansive properties of such a material
when pure, are constant.

In a mercurial thermometer, however,
the degree is not measured by the ex-
pansion of the mercury only; the glass
containing it also expands. The scale,
therefore, depends upon the relative ex-
pansion of mercury and glass. The lat-
ter varies considerably both in manu-
facture and in expansive properties, so

August 1. 191 I

POWER

165

that for a standard scale it must be
specified with great care.

Owing to the difficulty of obtaining
glass with identical qualities, it was
sought to reduce its influence upon
thermometric indications by using as a
substitute for mercury, a material whose
total expansion would be very great com-
pared with that of the glass. For the
h loior

perotur^. Degrees Fahrenheit-

Fic. 2. Variation of Specific Heat with

Temperature

expansive material, air was commonly
used among the early investigators;
later, nitrogen and hydrogen came into
more extensive use.

Gas thermometers are of two types:
constant pressure and constant volume.
The former uses the expansive properties
of the fluid as in the mercury thermom-
eter, while the latter measures the tem-
perature indirectly by the pressure which
varies directly as the temperature, ac-
cording to Boyle's law. The resulting
scales are different, but this difference
is so slight (their variations being but
a fraction of a degree ) that for most
engineering purposes it is not necessary
to discriminate between them. The gas
scales are very nearly coincident with
each other and with the theoretical work
scale devised by Lord Kelvin. The mer-
cury scale, however, is higher than the
others between the freezing and boiling
points of water.

The nitrogen scale is the one com-
monly employed in scientific work, but
the standard (between the freezing and
boiling points) is that of the constant-
volume hydrogen thermometer. This was
defined in 1887 by the International
Bureau of Weights and Measures. The
standard instrument is operated at an
external pressure of one standard at-
mosphere, or 760 millimeters of mercury,
and the hydrogen is maintained at a
pressure (when at the freezing point)
of one meter of mercury.

It has been previously mentioned that
the specific heat of water varies with
the temperature. It follows that, to be
precise, the heat unit must be based
upon a particular temperature range.
Unfortunately several such ranges have
been chosen for this purpose. Among
the earlier investigators, the freezing
point was adopted as a standard tem-
perature from which to measure, and the
unit of heat was that amount necessary
to raise one pound of water from 32 to
33 degrees Fahrenheit. Later, another
temperature was chosen, that at which a
given weight of water has the least vol-

ume, namely, about 39 degrees. It be-
came apparent, however, that both were
inconvenient temperatures at which to
take heat measurements; hence, 62 de-
grees was chosen. Lately, there has
been a tendency favoring still another
unit, the mean B.t.u. This is the aver-
age amount of heat per degree required
to raise a pound of water from the freez-
ing to the boiling point.

The curve* in Fig. 2 shows the rela-
tion between the specific heat of water,
in mean B.t.u., and temperature. From it
can be obtained the relation between
the various units mentioned, and it is
seen that
I (62 degrees) B.t.u. = 0.9985 mean
B.t.u.

In the United States all three units
are in common use. For some reasons,
the mean B.t.u. seems the preferable
quantity. It is independent of the ther-
mometric scale since it is fixed by the
two temperatures which are the same
on all scales, and therefore is more pre-
cise.

Turning now to the work measure of
heat, this involves the conception of the
foot-pound, and the units of length and

Fig. 3. Device for Measuring Mechani-
cal Equivalent of Heat

force. The standard foot was fixed by
the same act which established the unit
of mass, and is defined by the relation

1 meter = 39.37 inches
the meter being that of the archives of
France.

Force is usually measured by the ac-
tion of gravity upon a standard mass.
It is the product of the mass and the
acceleration of gravity at the location
considered. But the action of gravity
(that is, the acceleration) varies with
the latitude and the hight above sea level.
Hence, a definite unit of force must
clearly define the location at which it is
standardized. At the third general con-
ference of weights and measures at
Paris, in 1901, this was done, and the
standard acceleration of gravity was
named as that at sea level and 45 de-
grees latitude, or 980.(i65 centimeters
per second per second. This in English

•This riirrp rnprp^rnf^ th<» nvcrnirf nf
"llBhtljr (lUTprlne vnlnp« fniin'l \>y n niimMfr
"f InvrKllenlnrf. n» romtilnr-fl lir Murk* «n&
Davl«.

units is 32.174 feet per second per sec-
ond.

To convert the measurements of force
made with a standard mass at any other
location into standard units, it is neces-
sary only to divide this force by the ex-
isting acceleration and multiply by the
standard acceleration.

The electrical unit of work may also
be mentioned, since heat has been meas-
ured in this unit, which is the joule, or
the work done in one second by one am-
pere of current against a resistance of
one ohm. Joules may be converted into
mechanical units by the following re-
lation:

I joule

3.204622 X o..sq;,7 X in'

980,665 X IJ
0-737.S standard joof-pouxds
The work measure of heat is dependent
primarily upon the establishment of the
mechanical equivalent; that is, the num-
ber of foot-pounds equivalent to one
B.t.u. This constant can be determined
only by experiment. Fig. 3 illustrates
a method by which it may be measured.
A falling mass is arranged to churn a
definite weight of water, and the tem-
perature rise due to churning is noted.
The work done by the weight is thus
directly converted into heat. Knowing
the work done and the heat resulting
froin it, the number of foot-pounds
equivalent to one B.t.u. may be cal-
culated.

If this apparatus is applied to raise
the temperature of the water, degree by
degree, and the work done for each de-
gree rise is calculated, the resulting
values will show the variation of the
specific heat of water. Fig. 4 shows the
probable variation of the mechanical
equivalent of one degree rise of a unit
mass of water with the temperature. The
mean hight of the curve, shown by the
dotted line, is the value of a mean B.t.u.
It is not an easy matter to measure
these quantities with precision. During

3|'77&5

....

^

^

^-

1

Vi VI 75 100 125 150 175 JOO TR

Temperoture, Degrees Fahrenheit **"^

Fig. 4. Variation of Mechanical Equiv-
alent with Temperature

the last sixty years there have been at
least nine valuable investigations (and
many others of ininor importance) to
determine the mechanical equivalent of
heat, and each result differs from the
others hy amounts which, although small,
are important. The early investigators
were beset with difficulties, principally
because of the crude apparatus and their
comparative ignorance of the physical
properties of materials. Of late years.

166

POWER

August 1, 1911

however, several independent investiga-
tions have made the value of the equiva-
lent reasonably certain.

The first to furnish a value for the
mechanical equivalent of heat was Pro-
fessor Mayer, who, in 1842, published
a determination depending upon the
specific heat of air. He calculated the
work done by its expansion in a closed
cylinder while being heated. Then, know-
ing the amount of heat required to raise
the temperature one degree (no external
work being done) and the similar amount
of heat transferred during the actual ex-
pansion, the mechanical equivalent was
calculated by equating the difference of
these quantities to the work done. As
the data available at that time were not
accurate, Mayer's estimate was also in-
accurate.

About the same time. Doctor Joule, of
Manchester, Eng., was making independ-
ent e.\periments along the same lines.
Between 1843 and 1845 he published
the results obtained by three different
methods: First, by measuring the heat
generated by the current from a small
dynamo and the work necessary to drive
it; second, by a water churn similar to
that illustrated in Fig. 3, and, third, by
experiments on air along the same lines
as Mayer had worked. One of these
results was a very close approximation;
the others varied from it by 10 to 15
per cent. In 1850, Joule published his
first determination of real value. This
was obtained by an apparatus similar
in principle to that shown in Pig. 3. The
weights were alternately raised and
lowered, and observations were made of
all conditions affecting the test, which
was repeated many times. After making
all corrections, such as allowances for
friction, radiation, absorption of heat by
the vessel containing the water, etc..
Joule came to the conclusion that the
inechanical equivalent of heat was 772
foot-pounds at Manchester for each B.t.u.
at about 60 degrees on the mercury
scale.

About a quarter of a century later.
Joule made another determination by
electric measurements. The heat pro-
duced in a known resistance by a known
current was equated to the work equiva-
lent of the current. By this method his
result was so different from his first
value that he was led to repeat the
water-churning experiment. In 1878 he
published his final result, which agreed
closely with the experiment of 1850, being
772.5 Manchester foot-pounds for each
B.t.u. at 60 degrees on the mercury scale.
His apparatus for this test was much
the same as before except that, instead
of using weights, the work was measured
by a device in principle like Fig. 5. This
is similar to a prony brake, the paddle
being revolved by hand. The work done
is proportional to the rate of turning and
to the force necessary to hold the vessel
stationary.

The next to investigate the mechanical
equivalent of heat was Professor Row-
land, of Johns Hopkins University, who,
in 1878, repeated Joule's work on a
larger scale. The tests were conducted
at Baltimore, to which latitude the re-
sults were referred. He employed an
apparatus similar in principle to that
shown in Fig. 5, but very elaborate in
the perfection of its mechanical details.
The paddle was revolved by a small
steam engine and the measuring appa-
ratus was a model of refinement and
delicacy. Mercury thermometers were
used which had been standardized by
comparison with an air thermometer
which, in turn, was corrected to give tem-
peratures on the work scale.

Rowland's investigation covered a
larger temperature range (from 41 to 97
degrees! than Joule's and his results
were higher. His value at 58 degrees
was 779.2 foot-pcunds at Baltimore per
B.t.u. on the absolute scale. He com-
pared his results with Joule's and showed
that after the latter's had been corrected
for latitude and the differences in the

Fic. 5. Water Brake for Measuring
.Mechanical Equipment

thermometric scales, they were almost
coincident with his own.

Another determination by water fric-
tion was published in 1897 by Professors
Reynold? and Moorby. Their apparatus
was similar in principle to that shown
in Fig. 5 it being a water brake for a
100-horsepower engine. The water was
heated, in passing through the brake,
from 34 to 212 degrees and a large
amount of it was used, the rate being
varied so as to maintain the issuing tem-
perature at 212 degrees. The mechanical
equivalent obtained was 777.5 foot-
pounds for each mean B.t.u.

A number of investigations have been
made comparatively recently by means
of electrical measurements, among which
are those of Griffiths (1893), Schuster
and Gannon (1895), and Callendar and
Barnes (1902), the last named being the
most notable. The method here em-
ployed was to heat a continuous stream
of water from 32 to 212 degrees by a
measured current. The result, as pub-
lished, is 4.186 joules per mean calorie,
or about 777.8 standard foot-pounds per
mean B.t.u.

Professor Smith, of the University of
Michigan, has corrected Reynolds' figure
for the error involved in not starting at
32 degrees. The revised value is 777.6
standard fooi-pounds per mean B.t.u. He
also corrected Barnes' value for the
c.m.f. of the Clark cell so that this re-
si'lt, as revised, is a little less than 777.5,
the units being the same..

The accompanying table gives the re-
vised results of the investigators men-
tioned in this article. The figures in
the first column are in standard foot-
pounds per B.t.u. at 59 degrees Fahren-
heit, on the nitrogen scale. This scale
is selected because most of the results
are quoted in its terms. To convert the
mechanical equivalent to terms of the
standard hydrogen scale, it is necessary
only to add 0.3. The second column
gives the corresponding values expressed
in mean B.t.u.

Standard Foot-
pounds per B.t.u.

at 59 Degrees Mean

(Nitrogen Scale) B.t.u.

.Joule (average result). . 776.6 777.3

Rowland 77S.2 778.9

Griffllh 779.0 779.7

Schuster and Gannon.. 779.1 779.8

Reynolds and .Moorby. . 777.5

Callendar and Barnes,. .... 7*7.6

Griffiths' and Schuster's results are
higher than any of the others. In this
connection it may be noted that they
were obtained by the electrical method.
This indicates a constant error in the
electrical standards. On the other hand,
Barnes' result, similarly obtained, is low-
er than all except Reynolds'. Griffiths
worked between 59 and 78degrees Fahren-
heit and Schuster at 66 degrees only.
The two determinations covering the
whole range from 32 to 212 degrees are
practically coincident. It appears, then,
that the discrepancies may be due in part
to errors in electrical measurements and
to lack of knowledge of the variation of
the specific heat of water.

Professor Peabody has adopted Row-
land's value of 778 foot-pounds per B.t.u.
at 62 degrees, whereas Marks and
Davis have adopted Professor Smith's
estimate of the mecfianical equivalent.
This is a mean between the corrected re-
sults of Reynolds and Moorby and Barnes.

It may be observed that the average
of these results, omitting Griffiths' and
Schuster's and Gannon's figures, which
may have a common error, is 777.8. This
agrees fairly well with Professor Smith's
estimate.

It seems reasonable to give equal
weight to all the results listed (except,
perhaps. Joule's), Griffiths' and Schuster
and Gannon's being included because of
the extreme carefulness of their experi-
inental work. The average value is then
778.5 foot-pounds per mean B.t.u. and
the probable error is 0.3 foot-pound. The
mechanical equivalent of heat, therefore,
lies between 778.2 and 778.8; this esti-
mate being dependent upon the transla-
tion of the value at 59 degrees to the
mean heat unit.

August 1, 1911

P O W E R

The Combustion of Town Refuse

■The sanitary and economical disposal
of town refuse by cremation in a de-
structor is a problem that has engaged
the attention of engineers for something
like half a century, and during the last
decade it has been complicated by the
desire of turning to useful account the
heat generated in the destructor. With
the growth of towns both questions, par-
ticularly the former, become of some
importance. It is no longer considered
sanitary or even expedient to dump ref-
use on some unoccupied piece of land
and to leave it to work out its own salva-
tion by a process of decomposition;
neither is it by any means so usual to
deposit it in the sea, to employ it for
manure or partially to cremate it in in-
efficient furnaces operating in connection
with some private factory. Prior to the
advent of the modern sanitary destructor

By Francis H. Davies

The primary function of a
refuse destructor should be
to dispose of refuse. The
poicer obtained is a sec-
ondary consideration. Sev-
eral types of destriictor are
illustrated and their ope-
ration discussed.

According to Hutton the average com-
position of town refuse is as follows:

Weight,
Percent.
50.0

a good proportion of the refuse con-
sists of incombustible and wet substances,
such as scrap metal, crockery and vege-
table matter. Likewise, since the cinders

Chimney

Beehive Destructor

these or like courses were necessary,
but their unsatisfactory nature coupled
with the fact that under favorable con-
ditions the destruction of refuse may be
carried out at a profit arising from the
sale of the furnace residue and the use-
ful employment of the heat, has resulted
in the installation of a very large number
of such plants.

Primarily, the function of a destructor
is to dispose of refuse; the power that
may be obtained from the heat of com-
bustion should be looked upon as a
byproduct and not, as it has been in cer-
tain notorious failures, as the objective
of the installation. In sound practice,
therefore, the second consideration is to
some extent subordinated to the first, and
the destructor is designed primarily to
deal with the refuse in a manner that is
effective and inoffensive.

The quality of refuse varies within
wide limits according to the district and
time of year. A town in which there is
a considerable wood-working trade or
other industry' employing material of high
calorific value will naturally prove an
easier proposition than one in which

and ash from domestic hearths or stoves
are generally present in good propor-
tions, it follows that the refuse of the
summer months may not be of equal

Breeze and cinder

Paper, straw, fit)rous material and vege

table refuse 130

I'oal 0 7

Bones and oflal 0 6

Rags 0.4

Coke 0.3

-Ash 12.0

Dust and dirt 20 . 0

Bottles. 1 per cent.; tins, 0.7 per cent.;
metals. 0.2 per cent.; crockery, 0.6 per

cent.; broken glass, 0.5 per cent 3.0

100 0
It will be seen that the bulk of house
refuse consists of good combustible ma-
terial, but this, of course, does not repre-
sent the average quality of town refuse
which will always contain a proportion
of street sweepings and other substances
of low calorific value. It is the pres-
ence of such low-grade material that
has made efficient and hygienic cremation
a difficult problem.

Under proper furnace conditions it is
quite possible to deal effectively with
any class of refuse so far as its destruc-
tion is concerned, but it is equally as
important that the operation should not
result in the production of smoke, dust
and noxious fumes. In the early days
this constituted the great trouble with
destructors, and it will therefore be of
interest to examine the steps taken to
overcome this and other difficulties.

The rules which primarily govern the
design of modern furnaces may be stated
as follows: Furnaces or grates must be
so arranged that they may be fired and
cleaned alternately in order to keep the
temperature as uniform as possible. It
is also important that there should be a
minimum influx of air during the opera-
tions of firing and clinkering, to prevent
the temperature of the furnace falling

Main
Flue

^^

1

■V. ■ J-

.;\ _.z

HoRSFALL Destructor

value to that of the winter. However,
this and similar points will depend en-
tirely upon local conditions, and it is
obviously impossible to generalize in a
matter where special circumstances will
carry so much weight.

too low. A combustion chamber of ample
size and common to all the grates of
one furnace or to the cells of separate
furnaces, whichever system is employed,
must be provided and, preferably, it
should be placed between the fires and

POWER

August 1, 1911

the boilers where the latter are installed.
Many destructors have been built with
the combustion chamber after the boiler,
the theory being that the latter will in
that position be subjected to the greatest
heat. This is no doubt true, but it is
clear that the presence of a large and
comparatively cool surface in close
proximity to the fires will militate against
efficient combustion of the gases, a por-
tion of which may well pass through to

Fig. 3. Baker Destructor with Return-
tubular Boiler

the flues unburned and thus give rise to
objectionable emanations from the chim-
ney. There is obviously a difference of
opinion on this point, and the system em-
ployed must be largely influenced by
local conditions and the results it is de-
sired to attain. In any case, the brick-
work of the combustion chamber should
be massive in construction in order that
the largest possible amount of heat may
be stored. At times of firing and clinker-
ing the temperature of the furnace
naturally drops, and heavy brickwork at
a high temperature will tend to reduce
this and generally to maintain uniform
heat conditions.

The combustion chamber, besides ful-
filling the important function of burning
the gases, acts as a trap for the dust
carried from the furnace by the draft.
One of the great objections to destructor
installations in the early days was the
quantity of fine dust delivered from the
chimney, and it is most essential if this
nuisance is to be avoided that proper
arrangements should be made for trap-
ping it. It is also desirable from the
point of view of boiler efficiency, since
dust carried past the combustion cham-
ber will partly settle on the tubes or
heating surface of the boiler and serious-
ly impair its steam-raising powers.

The question of draft is all important,
and it is only by means of forced draft
with a closed ashpit that efficient crema-
tion of refuse can be effected. There
are two methods in use for producing
the blast, namely, steam jets and fans,
and there is little doubt that the latter is
preferable. The steam jet possesses the
initial advantage of cheapness to install,

and it is a generally accepted fact that
the steam coming into contact with the
incandescent fuel generates a water gas
which helps materially in raising the tem-
perature of the furnace. The chemical
action is as follows. The steam is de-
composed when it touches the fuel, the
hydrogen being liberated and the oxygen
combining with the carbon in the fuel
to form carbon monoxide. The mixture
of hydrogen and carbon monoxide, known
as "water gas," then passes upward and
is burnt by the excess air over the fire.
A further benefit of the steam jet lies
in its cooling effect upon the furnace
bars. The steam is condensed by contact
with the cool air it injects, and the re-
sultant water is reevaporated when it
touches the hot furnace bars. The effect
of this cooling is to prolong the life of
the bars, and in some instances where
fan draft is employed a small steam jet
is also installed specially for this pur-
pose.

The chief objection to the steam-jet
method of producing draft is its cost.
The percentage of steam taken may be
anything from 10 to 20 per cent, of the
output of the boiler, and this compares
very unfavorably with the 4 to 5 per cent,
required by steam-driven low-pressure
fans. The choice between the two must
be influenced by the value set upon the
steam generated. If there is plenty of

the custom to preheat the air, and one
of the most effective systems is that
shown in the part of Fig. 5 marked "re-
generator." This consists of a series of
tubes placed in the main flue, and the
air which is drawn across their surface
is thus delivered to the furnace at a
temperature which may be as high as
400 degrees Fahrenheit above the atmos-
phere. Another method used in the de-
structor illustrated in Fig. 2 is that in
which the air is preheated by being
passed through side boxes placed between
the grate and the brickwork. From the
point of view of heating it is compara-
tively inefficient as the increase in tem-
perature is something under 200 degrees
Fahrenheit, but the fact that these boxes
prevent the adhesion of clinker to the
side walls of the furnace is important, as
repairs to the brickwork are thereby re-
duced considerably. A disadvantage which
this system in particular suffers from is
that when the operation of charging is
performed and the heat of the furnace
is temporarily reduced the heat of the air
supply is also lowered. This, of course,
is exactly opposite to the most desirable
condition which is that the temperature
of the draft should be high directly after
charging in order to assist in drying the
refuse and igniting it.

A third system of preheating which
has been introduced by Heenan &

Fig. 4. Horsfall Destructor with Water-tube Boiler

more useful work for it to perform it
would be a mistake to waste such a high
percentage in producing draft; but if, on
the other hand, there is a good surplus
and the boiler is always worked lightly,
no object would be served by installing
a comparatively costly fan outfit.

It is well known that a hot-air draft
is preferable to a cold one in connection
WMth furnaces, and this is particularly
the case with destructors. It is therefore

Froud is better in this respect since it
affords the maximum of heat at the-
moment of charging. In the ordinary
way the draft is heated by a regenerator,
but after the fires have been clinkered
it is. in addition, made to pass through
a special pit beneath the grate in which
the red-hot clinker lies, and by this means
its temperature is materially increased,
while the clinker is to some extent cooled
and therefore more easily handled.

August 1, 1911

POWER

169

The intensity of draft is an important
matter since it has an appreciable bear-
ing upon economy. It varies in different
installations from 1 to 6 inches of water
column, and in cases is even higher. It
is, however, not desirable to use a greater
draft than is absolutely necessary, as
with a high pressure there is always
the possibility of blowing holes in the
fire with resultant loss. Further, it must
be remembered that increased draft
means increased power absorbed in its
production and, as previously pointed
out, it is quite possible to carry this to a
point at which the useful output of the
boiler is seriously diminished.

The charging of destructors is general-
ly performed by hand, in some cases
either from the front or the back of the
furnace by shovel, and in others through
the furnace roof at the top. The alter-
native to these is mechanical charging,
which, although involving some extra
complication, is decidedly more sanitary.
Hand charging of any sort besides being
unpleasant and unsanitary possesses the
disadvantage that a good deal of loss is
occasioned through open fire doors by the
influx of cold air. On the other hand, it
is the only system by which it is pos-
sible to discriminate in the quality of
refuse fed into the furnace, and this
feature is a valuable one where steadi-
ness of steam pressure is to be con-
sidered. In a mechanical system where
each load as it arrives is dumped into the
furnace by tubs or some such appliance,
discrimination cannot be exercised, and
while mechanical charging certainly
scores upon the point of sanitation it is
wanting in what is often the important
one of easily regulated steam pressure.
Many of the difficulties met with in
the design of destructors and a general
idea of the various methods of operation
will be gathered from the illustrations.
Fig. I is a sectional diagram of a very
early type termed the Beehive, and it
is of particular interest as it shows that
at that period it was not considered pos-
sible to maintain a fire with refuse alone.
It will be noticed that to meet this diffi-
culty a secondary grate for burning coal
was arranged under the main grate, and
the refuse on the latter was first stewed
and dried by the coal fire and then more
or less effectively burnt. This, of course,
was a most undesirable process, since
besides being costly it gave rise to dense
smoke and objectionable smells, which
indeed were so bad that some destructors
of this type had to be shut down shortly
after starting. The furnace was depend-
ent upon a chimney only for its draff,
and there was no combustion chamber
other than the flues.

Fig. 2 shows a very different cell of a
type greatly in use and known as the
Horsfall destructor. The feeding hole
is at the back of and above the furnaces,
while the flue for the emission of the
gaseous products is over the dead plate

in front. The virtue of this construc-
tion is that the gases rising from the
refuse must pass over the hottest part
of the fire on their way to the main llue
and thus be brought into contact with
the extremely hot gases arising from the
combustion of the incandescent material
which has been raked onto the grate
bars and is burning under forced draft.
The cast-iron side boxes by means of
which the draft is heated are shown ad-
jacent to the grate.

The Baker destructor combined with a
return-tube boiler is shown in Fig. 3.
Here the boiler is placed directly over
the refuse grate which is fed from the
back through a hopper. Over the fur-
nace is a reverbratory perforated fire-
brick arch, the heat of which assists in
cremating the gases arising from the fuel.

between this and the boiler, and an effi-
cient dust catcher is a special point of
this type of cell. The path of the hot
gases is across the boiler tubes and up-
ward to the main flue, and a coal grate
at right angles to the destructor grate is
provided. This may be used in con-
junction with the refuse furnace if de-
sired, or by closing the damper midway
between the two fires the boiler is isolated
and may be operated in the ordinary
way with coal. A feature of this de-
structor is the high-pressure blast, which
may be carried to 12 inches water gage;
it is found, however, that 6 inches is
ample to meet average conditions. The
air, which is heated by the side boxes
above described and usual in destructors
of this type, passes through numerous
small holes perforated in the solid iron

Fig. .=•. Mkldrlim Simplex Destructor with Lancashire Boiler

The gases flow through this arch and
pass over the heating surfaces of the
boiler, and it may be seen that there is
a supplementary furnace in the boiler
for burning coal which may be used when
the supply of heat from the refuse is in-
sufficient. When burning, this fire also
assists in cremating the gases arising
from the refuse. Clinkcring is performed
on the lower floor through a door In the
front, arrangements being made for rak-
ing direct into a small trolley.

Fig. 4 shows a recent type of Horsfall
destructor combined with a Babcock &
Wilcox marine-type water-tube boiler.
The refuse is fed by a special mechanical
system through the hole In the top of
the furnace, from whence it falls direct
onto the grate. It will he noticed that an
ample combustion chamber is provided

grate bars, and thus right into the burn-
ing refuse.

The drawings. Fig. 5, show the Mel-
drum Simplex destructor in combination
with a Lancashire boiler. The furnace
grate is continuous, but each section or
cell, as shown by the doors, is fired sep-
arately and each has also its own closed
ashpit and forced draft independently
controlled. By this arrangement the
green gases given off by a newly fired
section of the grate mix with the hotter
gases from those sections which are in
a more advanced stage of combustion,
and being burnt by them do not appear
in the form of smoke at the chimney.
This design and method of working re-
sult in uniform temperature in the com-
bustion chamber, a very important fea-
ture in the interests of sanitary opera-

170

POWER

August 1, 1911

tion and regular steam raising. Tiie
refuse is delivered close to the furnace
doors by means of a hopper, and it is
fired by hand. The regenerator pre-
viously mentioned consists of a number
of cast-iron pipes through which the fiue
gases pass. The air for the blast cir-
culates round the outside of these pipes
and is thence delivered to the blowers by
fans.

With regard to the amount of power
it is possible to secure from the com-
bustion of refuse in a properly designed
destructor, there are so many variables
which may enter into the case that it is
of little use to generalize. I'owever, the
following table, showing the average
vaporative power of town refuse, is given
by Hutton, and it is of interest as indi-
cating approximately what results may
be secured.

Weight of water
evaporated from
and at 212 deg.
F. per lb. of ref-
use fuel in lb.

Description.
Best screened ash-bin refuse. .
Average screened ash-bin refuse
Best unscreened ash-bin refuse
Average unscreened ash-bin

refuse

Inferior luiscreened ash-bui

Unscreened ash-bin refuse, 2
parts, mixed with 1 part
street sweepings, by weight.

Unscreened ash-bin refuse 2

parts, mixed with 1 part

street sludge, by weight . .

2.00
l..iO

0 50

Further data taken from particular in-
stallations might be cited, but as they
repiesent individually the results obtained
under one particular set of conditions it
is questionable if they would have much
value. It is sufficient to say that there
are numerous electric-power stations and
industrial plants drawing a good propor-
tion of their power from the combustion
of town refuse, and, although some are
failures financially, this is only the case
where insufficient care has been given to
the design or where a thorough examina-
tion of the local conditions if it had been
made would have shown at the outset
that, commercially, the proposition was
unworkable.

Test with Oil Fuel=i=

Some important tests with oil fuel were
recently conducted for the Government
at the works of the Babcock & Wilcox
Company, at Bayonne, N. J. The boiler
tested was of the type to be installed on
the new battleships "Wyoming" and
"Arkansas" but was of smaller size. It
had 2571 square feet of heating surface,
a furnace volume of 271 cubic feet and
a stack extending 100 feet above the
burners. The grates were removed and
the ash pans bricked over. Steam jets
were placed in the stack to assist the
draft and the closed fire-room system
was employed.

A heavy, viscid Texas crude oil was
used in eleven Peabody mechanical-ato-
mizer burners. This oil contained about

•Al)stiaoted from report In the Journal of
the Amei-ican Society of Naval Engineers.

19,290 B.t.u. per pound with a specific
gravity of 0.9322 and had a flash point at
295 degrees Fahrenheit.

During the first three tests the draft
was measured at the last pass, while in
the three succeeding tests it was also
measured at the first pass. Gas sam-
ples were taken from the uptake by
means of a ^-inch pipe leading to an
Orsat machine.

The oil was run into weighing barrels
direct from the tank cars and after be-

At half-hour intervals the quantity of
oil remaining in the barrel was checked.

The boiler was handled during the
tests by experienced men in the employ
of the company and all operations were
closely supervised by the Government
board.

The tests showed the desirability of
making gas analyses at frequent inter-
vals when burning oil; also of closely
watching the temperatures of the uptake.
Furthermore, it was found that the char-

OIL TESTS OF BABCOCK & WILGOX MARINE BOILER

I^umber of test

Duration of test, hours

Kind of oil

Oil burner used

Number of burners in use

Average Pressures

Steam pressure by gage, pounds

Oil pressure by gage, pounds

Draft pressure in fireroom, inches of water. . .
Draft pressure in furnace, first pass, inches of

water

Draft pressure near uptake, inches of water.

Average Temperatures

Outside air, degrees Fahrenheit '.

Fireroom, degrees Fahrenheit

Steam (at gage pressure, tables), degrees Fahren

heit

Oil, degrees Fahrenheit

Feed water entering heater, degrees Fahrenheit
Feed water entering boiler, degrees Fahrenheit .
Chimney gases, degrees Fahrehheit

Oil

Weight of oil used during trial, pounds

Steam

Quality, per cent

Water
Total weight of water fed to boilers corrected for
inequality of water level and steam pressure at

begmning and end of test, pounds

Equivalent weight of water evaporated into dry

steam, pounds

Factor of evaporation

Equivalent weight of water evaporated into dry
steam from and at 212 degrees, pounds

Oil per Hour

Oil per hour, pounds

Oil per hour per cubic foot furnace volume.

Founds
per hour per square foot of heating surface,

pounds

Oil per hour per burner, pounds

Equivalent to coal per square foot of grate sur-
face, pounds

Water per Hour

Feed water per hour, pounds

Water per hour, corrected for quality of steam

pounds

Equivalent evaporation from and at 212 degrees

per hour, pounds

Equivalent evaporation from and at 212 degrees

per square foot of heating surface, pounds. . .
Equivalent evaporation from and at 212 degrees

per cubic feet of furnace volume, pounds. .

Economic Results
Water evaporated per pound oil, pounds. . . .
Equivalent evaporation from and at 212 degrees
per pound of oil, pounds

Flue Gas Apalijsis

Carbon dioxide, per cent

Oxygen, per cent

Carbon monoxide, per cent

Nitrogen, per cent

Efflciencij
Efficiency of boiler

209.9
191.1
2.60

210.4

188.8

1.69

.391.5
175.3

47
168.6
T71

5,943

99.189

2,97;

13.69

1.15(
270.2

75.34

37,449
37,146
40.712
15.83
187. 6Q

12.60
13.70

5,11
99.290

1,704

7.85

0.663
213.0

37.45

22,345
22,187
24,494
9.53
112.87

13.11
14.37

9.26

7.68

0.00

83.06

110.7
73.6

1.18

3,605
99.83

18,89;
7.35

2,665
99.891

666
3.0

16.13

10,024
10,046
10,569
4.11
48.70

15.04

11.86
4.08
0.04

84.02

214.8

171.8

1.64

5,76
99.782

1,922

8.86

0.74;
240.3

43.96

25.238
25,183
27,149
10.56
125.10

13.13
14.12

5,840
99.835

1,947

8.97

0.757
243.4

46.14

27,858
27.812
30,064
11.69
138.53

14.31
15.44

10.94
4.73
0.00

84.37

ing weighed was pumped to one of two
receiving barrels. These two barrels were
connected at the bottom by a 4-inch pipe,
the oil-feed suction being led into the
second barrel. The latter also received
the overflow from the relief valves of the
oil-pressure pump. From the top of this
barrel ihe hight of the oil was measured
by a gage, to determine the quantity
burned. From the pressure pump the
oil passed through strainers to the heater.

acter of the smoke was an excellent guide
to the results which were being obtained;
in fact, changes in conditions were noted
by the character of the smoke before they
were apparent from the gas analysis.
During test No. 1 the maximum rate of
combustion was attained , this^ being
13.69 pounds of oil per cubic foot of
furnace volume per hour, or the equiva-
lent of 75.34 pounds of coal per square
foot of grate surface per hour.

August 1. U): 1

P O W E R

171

Design of

Selection of Steam Engines

The selection of a suitable type of en-
gine for a steam-power plant is governed
by the location of the plant and that of
the engine, the character of the service
for which the engine is required, the cost
of fuel delivered at the plant, the cost
and quality of water available for boiler-
feed and condensing purposes, available
Hoor space, class and number of men
necessary to operate and take care of
the plant, the first cost of the engine, in-
terest, depreciation and probable repairs.

It would be useless to select a high-
priced engine for the sake of economy
In the use of steam if the engine were
to be used for a short time only, or over
short periods of time. In such a case
the economical use of steam is of sec-
ondary consideration as the interest, de-
preciation, first cost and increased cost
of attendance, repairs, etc.. might ex-
ceed the saving in fuel effected by the
installation of the more economical en-
gine. Where fuel is cheap or where a
large quantity of exhaust steam is re-

Steam Power Plants

By William F. Fischer

Horsepower of Engine

Fic. I. Floor Space Required for Di-
rect-connected Units

quired for heating or manufacturing pur-
poses, it would be poor economy to in-
stall an expensive and economical engine.

Another point worthy of consideration
when selecting an engine is the time of
delivery, as the expense involved in a
long delay, including the interest on the
idle investment, may be such as to more
than offset the difference in cost between
two makes of engines. Where real estate
Is expensive and the floor space is lim-
ited, engines of the vertical type are
frequently installed in preference to
those of the horizontal type, but as they
require more headroom they are often
undesirable in office buildings and hotel
basements, etc.

Class for class, the steam economies
of vertical engines and horizontal en-
gines are practically the same, but in at-
tendance and repairs the vertical engine
requires closer attention.

When selecting an engine to drive an
electric generator, care should be taken
to see that the engine is neither too
large nor too small for the generator.
Each engine and each generator has its

The factors to be taken into
consideration -when select-
ing an engine for a given
service, and the characteris-
tics of various types of en-
gine.

point of maximum efficiency as a com-
bined unit; therefore they should be so
selected and operated as to attain their
maximum efficiencies at the same load.
Ordinarily, the horsepower of the engine
should be about 50 per cent, in excess
of the generator rating in kilowatts.

It is customary for electrical purposes
to make engines capable of developing
about 25 per cent, overload when running
condensing and full load when running
noncondensing. In plants where the load
is constant, or nearly so, the selection
of an engine is a very simple matter,
but where the load varies considerably
the units should be selected with a view
to operating each at its maximum effi-
ciency during the greatest possible num-
ber of hours. For the sake of economy
the engines should be of such capacities
and so duplicated as to be put in and
taken out of service as the load increases
and decreases; and while in service each
engine should be operated at its most
economical load.

Engine Types

Simple engines are used largely for
small high-speed units or where fuel is
cheap. For larger units and in places
where fuel is expensive, compound en-
gines are generally used as the increased
economy in steam consumption usually
more than offsets the increased first
cost. For steam pressures over 100
pounds per square inch and capacities
over 150 horsepower, compound engines,
whether operating condensing or noncon-
densing, will ordinarily save enough in
fuel consumption to pay for their in-
creased first cost. Moreover, the In-
creased cost of the engine is partly off-
set by less boiler capacity being re-
quired.

Triple-expansion engines are seldom
used for mill and electric-power plant
service where the load fluctuates widely,
as they rarely show a saving sufficient
to warrant their use when the increased
first cost, maintenance, etc., arc taken
Into account. They are, however, used
to a large extent in pumping stations
where the load is practically constant
over long periods. It is not desirable to
operate a triple-expansion engine under
less than 150 pounds steam pressure.

Engine builders usually arrange their
patterns of the different sized engines
so that each can be built with a number
of different strokes. The purchaser may
thus obtain an engine of long stroke and
low rotative speed, or one of short
stroke and high rotative speed.

High-speed Engines

All the early electric generators were
belt driven and of small capacity and
high speed, requiring comparatively small
engines. As there grew a demand for
units of larger capacity it was found in-
convenient and cumbersome to belt from
low-speed engines to high-speed gen-
erators; hence high-speed engines were
introduced for direct-connected units.
With engines of 100 horsepower or less,
it is usually desirable for economy to
employ an engine of moderately low
speed and belt from the engine to the
dynamo, providing there is sufficient floor
space to accommodate the belted-type
unit. In this instance, the loss due to
the friction of the belt, which may vary
from 5 to 10 per cent., is not sufficient
to warrant the additional first cost of a
direct-connected engine and dynamo. On
account of the saving in floor space and
in fuel, however, direct-connected units
are preferable in sizes over 100 horse-
power.

Alodern high-speed engines have many
advantages over the low-speed types.
For a given horsepower they are more
compact, require smaller foundations
and smaller buildings than the low-
speed type, and are, as a rule, simple
in construction and easy to operate. On
the other hand, although relatively low

of Engine

Fig. 2. Floor Space Required for Belted
Units

in first cost as compared to the low-
speed type, they are subject to greater
wear and tear and depreciate more rapid-
ly. Also, they are usually less eco-
nomical in steam consumption than are
those of lower speed.

High-speed simple, singlc-valve en-
gines of the self-oiling type are quite
popular In hotels, office buildings and
small manufacturing plants, and arc al-
so used to a large extent in small steam-
power plants because of the few parts
to get out of order, and the minimum

172

POWER

August 1, 1911

amount of attention required for their
operation. They are seldom operated
condensing, however, since in most cases
the gain in fuel economy due to adding
the condenser is more than offset by the
extra cost of the condensing apparatus
and its cost of operation and upkeep.
This type of engine may be had in sizes
up to 500 horsepower, but where fuel is
expensive it is not advisable to install
them in very large units unless the ex-
haust steam can be profitably used for
heating or manufacturing purposes.

SlNCLE-ACTlNG ENGINES

Single-acting engines are used exten-
sively for driving mechanical stokers,

T.\BLE 1. PRESSURE RANGE FOR VAHI-
OrS TYPES OF ENGINE

Range in

Average

Steam

Steam

Pressure,

Pressure.

Pounds

Pounds

Type of Engine

Gage

Gage

Simple low speed ....

60-120

90

Simple high speed ....

70-125

Compound high speed.

noncondensing

100-170

Compound high speed.

condensing

Compound low speed.

100-160

125

condensing

Triple-expansion, con-

140-210

Quadruple expansion.

125-225

200

conveyers, etc. They are cheap and sim-
ple in construction and run at high
speeds with little or no noise, depend-
ing on the care given them in opera-
tion. As a rule, they are much less
economical in steam consumption than
those of the double-acting type and are
thus seldom used in large sizes or where
fuel is expensive.

High-speed Multi-valve Engines

Modern four-valve engines show econ-
omies which approximate very closely
those of the Corliss, medium- or low-
speed types. These engines are built to
operate at practically the same speeds as
the single-valve high-speed type. The
valves are designed very much on the
same principle as the Corliss valve, but
instead of being operated by a dashpot,
are opened and closed by eccentrics on
the main shaft. This valve gear is more
flexible than that of the single-valve
engines, resulting in a better distribution
of the steam, closer regulation and less
valve leakage. They require closer at-
tention, however, because they are made
up of a greater number of parts.

Compound Engines

Where fuel is expensive and exhaust
steam is not required in large quantities
for heating or manufacturing purposes,
engines of 500 horsepower and over
should, as a rule, be of the compound
type. Besides requiring less boiler capa-
city than simple engines, they possess
the advantage of a more uniform pres-
sure on the crank pin which, in tur i,

produces a steadier turning motion on
the crankshaft.

It is not considered good practice
to operate a compound engine noncon-
densing, especially in the larger-sized
units; but whether the engines of a plant
should be run condensing or noncon-
densing depends upon several factors,
including the capacity of the station, the
nature of the load, the amount of water
available for condensing purposes and
the cost of pumping. Owing to the in-
creased cost of condensing apparatus,
piping, pumps, etc., and the increased
cost of attendance it seldom pays to con-
dense in very small stations. When se-
lecting a noncondensing compound en-
gine care should be taken to see that
the engine is not too large for the aver-
age power to be developed as the ex-
pansion of steam in the low-pressure
cylinder will be carried below the at-
mospheric pressure, when a light load is
being carried. This results in the high-
pressure piston dragging the low-pres-
sure piston against the resistance of the
atmosphere during part of the stroke,
the unnecessary work thus performed re-
sulting in a large waste of fuel. Care
should also be taken to see that the
cylinders are properly proportioned to
equalize the temperature range in each
cylinder if the best results are desired;
due to this cause compound engines
properly proportioned for condensing
will be wasteful of steam when run non-
condensing.

Rotative Speed

The terms "low speed," "moderate
speed" and "high speed" as applied to
steam engines refer to rotative speeds
only. The piston speed of a low-speed
engine, for example, might be consider-
ably greater than the piston speed of a
high-speed engine, due to the longer
stroke of the former engine. The rota-
tive speed at which an engine is to run
is determined by the service for which
the engine is required. If it is to be
coupled direct to the shaft of an electric
generator its design should conform to
the speed of the generator, or the design
of the generator should be adapted to the
rotative speed of the engine. As a high-
speed dynamo requires considerably less
iron and copper in its makeup, and con-
sequently weighs and costs less than a
low-speed machine of the same power,
high rotative engine speed is a desir-
able feature in direct-connected units.

The rotative speed is limited by the
centrifugal force developed in the fly-
wheel when in motion. Corliss and
similar engines with releasing valve
gears are not intended to run over 80 to
90 revolutions per minute; hence are
never used for driving direct-connected
generators of high rotative speed.

Piston Speed and Engine Regulation

A short stroke, besides permitting a

high rotative speed and thus reducing

the cost per horsepower of the engine
and generator, also makes the unit more
compact and requires a minimum floor
space. Frequently in power-plant ser-
vice the engine load is continually chang-
ing, and as any variation in engine speed
may cause electrical disturbances on the
system, it is of utmost importance
that the speed should be kept uniform
during all changes of load. Therefore,
the governor regulation should be close
under the most rapid fluctuations of
load, and the valve gear should work well
at any speed at which the engine will
run with good results. The governing of
engines for almost any kind of service
is now sufficiently well known for en-
gine builders to guarantee the required
regulation. This point should, however,
be made a part of the specifications for
the engines. Voltage regulators are al-
most invariably used in connection with
alternating-current work if both light and
power are to be supplied from the same
unit, or where voltage regulation is im-
portant. The voltage regulator in this
case performs the same service for the
generator that the governor performs for
the engine.

Stea.m Pressure
Table 1, from "Gebhardt's Steam Power
Plant Engineering," may be used as a
guide in determining the steam pres-
sure to be carried on the boilers for
different types of engines. The average
pressures ordinarily used are given in
the second column of the table. In the

TABLE 2. AVERAGE STEAM CONSUMP-
TION OF VARIOUS TYPES OF ENGINE
AND THE GAIN BY CONDENSING

-Average assumed
weight of steam
per indicated
horsepower per
hour* 1

Type of Engine

Gain by
Non- Con-
con- Con- densing,
densing , densing Per Cent.

Simple low speed.- .
Simple high speed. .
Compound high

speed

Compound low

speed

Triple-expansion low

speed

Triple-expansion

high speed

29
33

26

23

20

24

20 1 31
22 33

20 23

18 25
15 20
17 29

^.Assumptions based on average practice.

larger steam stations, however, the ten-
dency is toward the higher steam pres-
sures as given in the first column.

Where a steam pressure over 150
pounds per square inch is to be carried
more attention should be given to the
design and erection of the steam piping,
valves, fittings, etc.. but as the higher
pressure permits the use of smaller pipe
sizes the cost of the piping will be suffi-
ciently reduced to pay for a better class
of piping material throughout.

ECONO.MY AND STEAM CONSUMPTION

In referring to steam-engine economy
it is customary to state the economy in

August I, 1911

POWER

173

terms of the number of pounds of steam
consumed per indicated horsepower per
hour, and in this respect the terms "steam
consumption" and "water consumption"
or "water rate." as it is sometimes called,
are synonymous.

Table 2 shows the average steam con-
sumption of various types of engines
when operated condensing and noncon-
densing. and also the gain due to con-
densing. Much better results than these
are very- often obtained in actual prac-
tice with certain high-grade engines, but
the table may be safely used for deter-
mining the necessary boiler capacity. The
steam consumption of an engine will vary
considerably, depending upon the condi-
tions under which it is operated. It is,
as a general rule, less expensive to over-
load an engine than to run it constantly
underloaded.

The economy of a steam engine should
never be stated in the terms "pounds of
coal per hour" as this involves the econ-
omy of the entire plant, the quality and
kind of fuel, the skill of the firemen, the
efficiency of the boilers, etc., as well as
the general design and care of the steam-
piping system.

Figs. 1 and 2 show the appro.\imate
floor space required per horsepower for
direct-connected as compared with that
required for belt-driven units.

Smoke Prevention in Large

Power Stations*

By H. S. Vassar

The steam demand in a central station
is very different from that of a factory;
the load is apt to fluctuate rapidly and
sometimes as much as 50 or 60 per cent.
of the boiler capacity must be "broken
up" within perhaps 30 minutes.

Sometimes the sudden approach of a
summer shower will so increase the light-
ing demand as to call for six or eight
extra boilers in about as many minutes.
Again an accident at a congested point
in the street-railway system may cause
a blockade that will relieve the load so
promptly as to start all the safety valves
blowing. Perhaps within a few minutes
the load may return with an even larger
demand for steam, and fires must be
forced to meet it.

Other causes too numerous to mention
might be given for the occasional er-
ratic behavior of the load; it suffices to
say that the modern central-station en-
gineer is continually on the lookout for
such changes and. so far as it is possible,
strives to anticipate load variations by
bringing up the banked boilers slowly,
if time permits. But time is often lack-
ing, and then, regardless of the smoke-
preventing devices in use, the hurried
breaking up of banked fires produces
smoke.

•rrnm n pnper iIoMvprfKl Ix-forn th<> Intir-
nnttonnl AB«orlntIon for flip rrc^'pntlon of
SmLkf at NVwBrk, N. J., .Tiim- "JS, Kill.

One of the frequent structural diffi-
culties with which many boiler plants,
built up to six or eight years ago, have
to contend is the small combustion space
over the fire. Although this may be suf-
ficient if hard coal is burned, it is usual-
ly lacking when bituminous or semi-
bituminous coal is used. With a building
designed for low-set boilers, it is often
impracticable if not impossible to rebuild
the furnaces for the use of soft coal,
whether for hand firing or automatic
stokers.

The ease with which a soft-coal fire
responds to changes in steam require-
ments, together with the rapid rate at
which it can be burned, makes it par-
ticularly desirable for central-station use.
Moreover, hard coal, when the smaller
sizes are used with forced draft, is open
to the objection of the cinders being
distributed over the surrounding area.
This is considered by many almost as
great a nuisance as soft-coal smoke.
When it is necessary or desirable to use
soft coal with these old settings, some
of the numerous steam-jet devices will
sometimes lessen the amount of smoke
produced. The gist of the matter is that
such a setting is absolutely unfitted for
either smokeless or efficient operation
with soft coal. For this reason, few
of the large central stations of today
build new furnaces wfthout carefully
considering the nature of the fuel to be
burned and providing, to the best of their
ability, the proper combustion space over
the grate.

Efficient or smokeless combustion is
more or less handicapped by hand firing,
such firing requiring open fire doors dur-
ing from 10 to 20 minutes of each hour
when firing soft coal. Automatic stokers,
however, arc continually growing in
favor; and, although each type has its
own particular disadvantages, the gain in
efficiency resulting from their use is a
strong argument for their installation in
almost any plant burning 75 tons or more
per day. Some of the qualifications which
should characterize the mechanical stoker
for central-station use are:

1. Simple but substantial construction.

2. Small scrap pile.

3. No hand manipulation of the fire.

4. The rejection of a minimum amount
of combustible with the ash.

5. Ability to burn varying grades of
fuel economically at any rate up to 50
pounds per square foot of grate per hour,
and to meet the varying steam demand
promptly with a limited amount of skilled
attention.

Little need be said relative to the first
point. As to the second item, there arc
several stokers in use which require the
frequent replacement of grates, dumps,
etc., resulting in the accumulation of a
large scrap pile as well as the expendi-
ture of much labor, to say nothing of
the frequent shutdowns for such repairs.

The matter of no hand manipulation
of the fire is one of great importance.
If barring by hand must be done to any
great extent, either to secure proper air
admission or for the removal of clinker,
two of the most valuable gains due to
automatic stoking are lost; namely, labor
and efficiency, and excessive smoke in-
variably accompanies such handwork.

There is at present a movement for
skilled boiler-room supervision, brought
about partly because of a demand for
the elimination of smoke, but to a larger
extent as the result of an attempt to se-
cure higher boiler-room efficiency. The
principal reason for this increased atten-
tion to the matter of boiler-room op-
eration is evident. The central station
is in reality only a factory, its raw ma-
terial being coal and its finished product
electricity. In the older plants fuel
constitutes frum 40 to 60 per cent, of the
cost of electrical energy at the switch-
board and in later installations it is much
higher.

A few years ago the boiler-room econ-
omy was supposed to be looked after
by the superintendent or the chief engi-
neer. These men, however, have enough
on their hands in most stations without
tackling, other than superficially, prob-
lems that are worthy of the undivided
attention of at least one first-class man.
By supervision is not meant an occasional
trip through the boiler room, or a few
maledictions heaped upon the heads of
the firemen by a watertender; but con-
tinuous hour-to-hour supervision by a
trained man whose principal duty is the
economical burning of fuel.

Approximate Rule for Re-
ceiver Pres.snre f»r Equal
Loads

The following approximate rule for
finding the receiver pressure which
should be carried in order that the indi-
cated horsepower may be equally dis-
tributed between the two cylinders has
been devised by Thomas Hawley, of the
Hawley School of Engineering, at Bos-
ton:

Find the mean effective pressure by
the usual method, using hyperbolic log-
arithms, for the whole number of ex-
pansions, assuming all the work to be
done in the low-pressure cylinder.

As the low-pressure is to do only
one-half of the work, divide by
two, multiply this by the ratio between
the cylinder volumes to get the mean
effective pressure necessary for the high-
pressure cylinder. By subtracting this
from the mean pressure, as found by the
hyperbolic-logarithm formula for the
number of expansions in the high-pres-
sure cylinder at full pressure, the back
pressure necessary to give the required
mean effective pressure in that cylinder
is obtained. This will be the receiver
pressure.

174

POWER

Auaust 1, 191!

Operation and Connections of

Alternators Working in

Parallel

Bv Norman G. Meade

When operating alternating-current
generators in parallel it must be borne
in mind that if at any instant the elec-
tromotive force of one generator is
lower than that of other machines with
which it is connected, it will take cur-

FiG. 1. Illustrating the Principle of
Synchronizing

rent from the other generators instead
of feeding current into the line. Fur-
thermore, in order that the electromotive
forces shall be the same, the generators
must agree as to frequency, power fac-
tor and wave form; otherwise pulsating
currents will be set up. When similarly
designed machines are adjusted for the
same voltage and operate uniformly at
the same frequency, these conditions are
usually fulfilled.

Speeds

The speeds of the engines should be
adjustable while they are running in
order that they may more readily be
inade to correspond when the alternators
are being connected in parallel and that
the load may be properly divided.

When machines are operated in paral-
lel there is sometimes a tendency to non-
uniform speeds, which may be due to
any of several causes, such as a ten-
dency to different speeds; unequal en-
gine-speed regulation between no load
and full load; irregular speeds, such as
would be caused by a hunting action on
the part of the governors, giving rise to
a surging of load between the machines;

Especially^

conducted tohe of

interest and service to

the men in char^ej

of the electrical

equipment

irregular fluctuations of speed such as
would be caused by lack of uniformity
of angular velocity during a single revolu-
tion.

If the governors on the driving engines
give different speeds it is evident that
when two machines are in parallel that
which tends to run at the higher speed
will carry a greater proportion of the
load until the governor is adjusted for

Voltmeter

Ground Detector
Lamp

■■ Transformer

Ground Detector
Receptacle

their pioper amount of power. Alternators
driven by engines governed closely be-
tween no load and full load are usually
not as well adapted to running in multi-
ple as those in which the regulation is
not so close. In general the power de-
livered by a generator which is running
in multiple with other generators is not
dependent upon its field excitation but
only upon the governor adjustment of
the driving engine.

If a governor gives varying or irregu-
lar speed, first one machine and then
the other will carry the greater load.
The rapidity with which this change
takes place depends upon the rapidity
with which the governors oscillate in
their running action. This tendency to
varying speed is one of the most com-
mon sources of difficulty in parallel op-
eration. When two direct-current dynamos

Voltmeter Busbars

Synchronizing Busbars

'Synchronizing Plug

n ~"

^"v.- Synchronizing Plug

A; Phase I

B; Phased

vC«

Field Winding Field Winding

Fig. 2. Switchboard Connections of Two Low-tension Two-phase Alternators
Operated in Parallel

a lower speed, when the second ma-
chine will begin to carry load. Before
this condition is reached one generator
may be running as a motor.

The governing of the speeds of the
engines should be such that when run-

are running in parallel, slight changes
in their relative speeds, amounting to,
say, ' J per cent, or so, would make very
little difference in their operation. With
alternating-current dynamos, however,
the relation between speeds must be

ning at a common speed they will deliver practically constant.

August 1, 1911

POWER

175

Field Excitation
When the rheostats of two alternators
running in parallel at normal speed are
not adjusted to give proper excitation,
idle cross currents will flow between
the armatures; these depend only upon

or increasing that of the other; that is,
in both cases it will lead in the first ma-
chine and lag in the second machine.
The electromotive force of the system
w-ill, however, be decreased in the one
case and increased in the other.

.Voltmeter

Synchronizing Busjfors

Voltmeter

Synchronizing ^ ?i ' 7K "^

Fiogyj' ^Synchronizing La/nps V^^ — Synchronizing Plug^^ |

Voltmeter Busbar

Field Winding Field W„-d:ig Field Winding Po^w

Fic. 3. Switchboard Connections of Three Low-tension Two-phase
Alternators Operated in Parallel

the difference in field excitation of the
machines and they may vary over a wide
range — from zero, when both field ex-
citations are normal, to more than full-
load current when excitations differ
greatly. These cross currents increase
the temperature of the armatures and,
consequently, cut down the available out-
put of the alternators. It is therefore
important that the rheostats be so set
as to reduce them to the minimum. Cross
current is registered on the ammeters of
both generators and usually increases
both readings. The sum of the ammeter
readings will be minimum when there
is no cross current. In order to deter-
mine the best settings of the rheostats,
therefore, it is necessary to make trial
adjustments after the alternators arc con-
nected In parallel until the setting is
found which reduces the sum of the am-
meter readings to the lowest figure.

To illustrate this method, consider two
similar alternators A and B, operating in
parallel. When the rheostats of both are
properly adjusted no cross current will
flow through the armatures and the main
ammeters will show equal readings if
both machines are receiving the same
amount of power from their respective
prime movers. If the rheostat of A be
adjusted so as to reduce its field excita-
tion, a cross current, lagging in AJ and
leading in A. will flow between the arma-
tures, the effect of which will be to
strengthen the field magnetization of A
and weaken that of H until they are ap-
proximately equal. The resultant electro-
motive force of the system will thereby
be decreased. A cross current of the
same character is produced by decreas-
ing the field excitation of one machine

From the foregoing statements it is
obvious that by a combination of changes
in the two rheostats, that is, by cutting
one in and the other out at the same time,
the cross current may be varied con-

the other cut out the same amount, so as
not to vary the electromotive force of
the system seriously. If this reduces the
sum of the main ammeter readings, the
adjustment should be continued in the
same direction until the lowest possible
readings are obtained. After this point
is reached a further adjustment of the
rheostats in either direction will increase
the ammeter readings. If the first ad-
justment increases the sum of the am-
meter readings, it is being made in the
wrong direction and the rheostat handles
should be moved back slightly past the
original positions and the adjustments
in these opposite directions continued
as jusi described.

In iTiaking these adjustments of the
rheostats it may be found difficult to lo-
cate the exact points at which the cross
current is minimum, as it may be pos-
sible to move the rheostat handle over a
considerable range when near the cor-
rect position without materially chang-
ing the ammeter readings. When this is
the case the setting is good enough for
practical operation.

Synchronizing

The elementary principle of the method
of determining when alternators are of
the same frequency and are in phase is
illustrated by the diagram. Fig. 1, in
which A and B represent two single-
phase machines the leads of which are
connected to the busbars by the switches

onizing Bars

<s^KJ

Synchronizing,
Lamp -

A>t^' Synchronizing
Plug

Fir,. 4. SviiTr.HBnARn Connections of Two Two-phase High-tension Alternators
Operateo in Parallel

siderably while the electromotive force
of the system remains constant.

For the first trial adjustment one rheo-
stat should be cut in several notches and

C and to each other through two sets
of incandescent lamps D and E. It is
evident that as the relative positions of
the phases of the electromotive forces

176

POWER

August 1, 1911

change from that of exact coincidence
to that of exact opposition, the flow of
current through the lamps varies from
minimum to maximum. If the electro-
motive forces of the two machines are

ternators and the main switch closed. The
rheostat must then be adjusted to elimi-
nate or minimize cross currents and the
governors of the driving engines adjusted
to distribute the load between the al-

Busbors

The Connections shown
dotted are neassaryonly
when a Source of Current
other than the Generators
shown is connected to the
Busbars

Fig. 5. Switchboard Connections of Three Two-phase High-tension
Alternators Operated in Parallel

exactly equal and in phase they will op-
pose each other and no current will pass
through the lamps; if there is any ap-
preciable difference of phase the lamps
will light up and the greater the phase
difference the brighter will be the lamps.
The maximum brilliancy is reached when
the phases are in exact opposition. If
the machines are running at different
speeds they will come into phase and go
apart again; this will be indicated by
the lighting and extinguishing of the
lamps. The rate of pulsation of this
lighting and going out depends upon the
difference between the speeds of the ma-
chines; by adjustment of the engine gov-
ernors the rate can generally he reduced
to as low as one pulsation in ten seconds,
which affords ample time for closing the
switch connecting the generators in
parallel.

When the electromotive forces of two
alternators are precisely in opposition
to each other — in exact agreement at the
busbars — the machines are said to be
"in phase," "in step," or "in synchron-
ism." The apparatus used for determin-
ing when alternators are in phase is
called a "synchronizer."

Starting Up and Shutting Down

To start an alternator which is to op-
erate in parallel with other alternators it
should be brought up to the proper speed
in the same manner as a machine which
operates alone. The e.m.f. should then
be adjusted to equality with the e.m.f.
at the busbars, which is that of the gen-
erators with which the newly started ma-
chine is to be connected. It should then
be synchronized with the working al-

fheir

ternators in parallel accoraing lu
respective capacities.

When it is desired to cut out an al-
ternator which is running in parallel with
other machines, it is best first to reduce
the power of the prime mover until it
is just sufficient to drive the alternator

ing all the load on the remaining ma-
chines without having made any previous
adjustment of the load or of the field
excitation.

The field circuit of an alternator to be
disconnected from the busbars must not
be opened until after the main switch
has been opened; if the field circuit be
opened first, a heavy current will flow
between the armatures.

Switchboard Connections

The method of starting and stopping
two-phase and three-phase alternators is
practically the same as that for single-
phase machines but the connections and
switchboard apparatus are more compli-
cated. Fig. 2 shows the connections of
two 440-volt alternators connected in
parallel. It will be noted that there is a
set of busbars for the voltmeter and an-
other set for the synchronizing devices
in addition to the main-load busbars;
to these latter the ground detector is
connected. The hidden lamps connected
in series with the synchronizing lamps
are necessary on account of the voltage
of the machine; each lamp is made to
stand 110 volts and four are required
in series to stand 440 volts. Suppose,
for example, that generator No. 1 is op-
erating and it is desired to start gen-
erator No. 2. As with a single-phase ma-
chine, it must be brought up to normal
speed and voltage. The synchronizing
plugs for both machines are then in-
serted in the receptacles and when
synchronism is indicated by the lamps

.S t

^MM]

^-^mm

^-^mm

field Wirdircj

field Winding

Fig. 6. Switchboard Connections of Low-tension Three-phase Alternators
Operated in Parallel

without taking any load; the resistance
in the field circuit should then be ad-
justed until the armature current is
minimum, after which the main switch
should be opened. It is usually sufficient,
however, to simply disconnect the ma-
chine from the busbars, thereby throw-

the main switch of alternator No. 2 is
closed; then the cross current between
the machines is regulated by means of
the field rheostats.

Fig. 3 shows the connections for three
two-phase machines operating in multi-
ple. They are substantially the same as

August I, 1911

POWER

177

those shown in Fig. 2 with the exception
of the few modifications necessary where
more than two machines are used.

Fig. 4 shows the connections for the
parallel operation of two high-voltage
two-phase alternators, and Fig. 5 shows
the connections of three machines of the
same type operating in parallel. The
connections are practically the same as
those for low-voltage machines with the
exception that the switchboard instru-
inents are connected through small trans-
formers to reduce the voltage to a safe
value and the generator switches are
of the quick-break oil-immersed type.

The connections of three low-voltage
three-phase alternators operating in
parallel are shown in Fig. 6. The equip-
ment is similar to a two-phase installa-
tion with the exception that there are
three ammeters to each machine, one for
each phase.

The exact connections of alternators
will, of course, vary somewhat for dif-
ferent installations, depending upon the
special requirements, but they are all
based on the same general principles.

LETTERS

Mr. Crane's Switchboard

In the issue of June 20 there is an
article entitled "An Easily Built Switch-
board." The board described therein
merits the name given to it, as it can
be made easily and cheaply. It is not,
however, the type of switchboard that
should be used for permanent work if
any other could be obtained. It very
closely resembles the switchboards that
were installed about twenty or thirty
years ago, when electrical work was just
beginning. Since that time practically
all of the old boards have been super-
seded by others of which the switches,
circuit-breakers, instruments, etc., are
mounted upon slate or marble panels.
The reason for this is because of the
much greater safety from fire. Although
skeleton boards of the type described
by Mr. Crane are permitted by the fire
underwriters, they are not recommended
and the rules require that the wood not
only be hard, as stipulated by Mr. Crane,
but that it be filled, which he omitted
to state and which omission would pre-
vent obtaining an underu-riters' certificate
If noticed by the inspector.

I also take exception to the statement
that such a wooden board can be painted
and made to look much better than a
slate one, at least after six months of
use. With good care, a slate board
should retain its polish and good ap-
pearance indefinitely, and by "good care"
I mean nothing more than the ordinary
care that a careful and neat man would
give t«» such a board.

A statement which I cither "do not
understand or cannot believe, if my un-

derstanding is correct, is the one in the
last paragraph to the effect that in one
installation the entire cost of four motors
totaling 50 horsepower, with a skeleton
switchboard and instruments, was the
same as would have been the cost of the
switchboard alone if slate had been used
instead of wood. I should understand
by this statement that all that there was
to cause the difference in price w-as the
slate, and it would seem very strange
if the slate upon which the control ap-
paratus of the motors was to be mounted
should cost as much as the motors. New
motors of the sizes given would cost
at least $10 and probably S15 per horse-
power, or from S500 to $750 in all. They
could be easily controlled from panels
of the same size as shown in Mr.

be easily done if the board is no higher
than that shown.

G. H. McKelway.
Brooklvn, N. Y.

An E.^sily Built Switchboard

Crane's illustration or, if necessary, of
smaller size. Four such panels would
need but little more than 25 square feet
of slate; therefore, if the figures just
quoted are nearly right, about S20 or S30
per square foot would be the price for
the slate. This would seem to be im-
possible, so that ther? must have been
something omitted that is needed to clear
up the statement.

As shown in the illustration, the cir-
cuit-breakers are placed immediately
under the instruments and ver>' close to
them. It would be preferable to place
the circuit-breakers at the fop of the
board where there would be no danger
of an arc from one of them, when if
opened, scorching anything else on the
board. Circuit-breakers are gcncrilly
located at the top for this reason and
the resetting of them from the floor can

Mr. Crane's "easily built" switchboard
appears to me to be applicable princi-
pally to jobs requiring portability, such
as those done by contractors' plants
using electric power. This arrangement
will allow one to add more circuits or
apparatus readily and cheaply and at
the same time in such a manner as to
keep fire hazards down to a mi^imum.

The cost of this type of board, how-
ever, is very nearly the same as that of
a slate panel mounted on a pipe frame.
The frame will be the same for jithcr
type of construction; the crossbars
(which should be of treated wood) and
clamps and separate bases for the
switches and circuit-breakers will prac-
tically equal if not exceed the cost of a
suitable slate panel. The cost for labjr
and material for connecting the various
pieces of apparatus will be the same if
the work is done as it should be, and is
up to the usual standard.

In regard to the location of the appa-
ratus, the underwriters suggest that al!
carbon-break circuit-breakers be mounted
at the tops of panels, so that there will
be sufficient free space for the arc to
dissipate its heat. The arc on a short-
circuit, even at low voltage, when the
generator capacity feeding into the short-
circuit is large, is apt to cause con-
siderable damage unless located so that
it cannot reach metallic parts. If the
tip of a circuit-breaker is low enough,
moreover, it is very liable to burn the
operator should he be close enougn to
the board when the circuit-breaker
opens.

Mr. Crane claims cheapness as the
principal advantage, but very few people
would care to effect the small saving
in cost by allowing such a conspicuous
sacrifice in appearance.

A. L. Harvey.

Pittsburg, Penn.

A friend of ours was lamenting the
other day that after several years of
hard and continuous work one of his
boilers had had to be scrapped. He did
not mind so much that a new boiler had
to be purchased; but he did object to its
purchase being forced upon hitn n'ithout
a moment's warning. For the end came
very suddenly, after a.(. He had known
that it was probable that the insurance
companies would have refused to insure
the boiler unless the working steam pres-
sure were reduced; but he had not antici-
pated that the testing hammer of the in-
spector would have been driven clean
through a wasted plate and put the boiler
out of the running from that moment.
—Ex.

POWER

August I, 1911

Attachment for Running on
Low Grade Distillates

The accompanying engravings illustrate
an ingenious attachment which the St.
Marys (Ohio) Machine Company applies

Fig. I. Fuel Feeder

to its engines to enable them to run on
kerosene, any of the lower-grade petro-
leum distillates, or gas oil. The at-
tachment comprises a cast-iron fuel-feed
chamber provided with three atomizing
nozzles, a diaphragm valve and a buffer
plate which is adjusted by the governor
to limit the play of the diaphragm valve.
Fig. 1 shows the fuel-feed chamber,
ready to bolt on to the engine over its

Device in Position

intake; Fig. 2 shows it in place on the
engine, and Fig. 3 shows a sectional view
and the linkage between the governor
and the buffer plate B. The left-hand
nozzle G in Figs. 1 and 3 delivers gaso-
lene for starting purposes only; the right-
hand nozzle H' delivers water and the
top nozzle O delivers the petroleum dis-
tillate. The air intake is at A. After

starting on gasolene, with the other two
nozzles closed, when the chamber has
become warm, the oil valve is opened
slightly and the gasolene valve partly
closed; a few minutes later, the oil valve
is opened wide and the gasolene valve is
entirely closed, leaving the engine run-
ning on the oil alone.

After changing over to the oil fuel, the
water valve is opened slightly, admitting
a fine spray which mixes with the fuel
and prevents high e.xplosion pressures;

Governor Connection

the water is evaporated into steam, which,
of course, adds a little to the force ex-
erted on the piston during the expansion
stroke.

The fuel-feed chamber is water-jack-
eted, receiving its supply of water from
the outlet of the valve-chest jacket,
which is at a higher temperature than
the main jacket; this keeps it warm and
facilitates the vaporization of the fuel.

The speed is regulated by the adjust-
ment of the buffer plate B, Fig. 3; the
plate is mounted on two rollers which
travel on the inclined plane shown; as
the governor balls fly outward, in re-
sponse to an increase in speed, the plate
is pulled to the right and the travel of
the rollers up the incline raises the
plate to a higher level where it stops the
downward movement of the valve stem
sooner and thereby reduces the opening
of the valve V. The valve is drawn down-
ward by the suction of the engine and it
is arranged to vary the delivery of oil
in proportion to the quantity of air passed
by the diaphragm. The engine therefore
works with a practically constant quality
of mixture.

Constant Quality, Not Constant
Compression, Preferred

At the Pittsburg meeting of the Ameri-
can Society of Mechanical Engineers,
a written communication presented by
■Mr. A. E. Maccoun, of which we pub-
lished an abstract on pages 17 and 18,
July U, contained the statement that
the Edgar Thomson Works had found
the constant-compression method of
regulation better for all load conditions
than the constant-quality method. Mr.
Maccoun informs us that this was an
error fpresumably stenographic) ; his
experience has been just the reverse, the
constant-quality system being more sat-
isfactorv.

Operating Costs of Gas
Power Plants

The Plant Operations Committee of
the Gas Power Section of the American
Society of Mechanical Engineers pre-
sented at the Pittsburg meeting of the
society a report giving operating costs
from four gas-power plants, the names
and locations of which were withheld
by request of the plant owners. For the
purpose of identification the plants were
referred to by letters of the alphabet.
The essential features of the reports
are given herewith.

Plant "A"

Two pressure producers with gen-
erators 7 feet in inside diameter, wet
scrubbers 7'< feet inside diameter and
18 feet high and dry scrubbers 7 feet
square by 3'S feet high. The producers
use bituminous coal, costing S2.55 per
ton; two tar extractors are operated.

One double-acting single-tandem en-
gine with cylinders 23=jx33 inches. The
shaft runs in three bearings and is di-
rectly coupled to an electric generator.
Speed, 150 revolutions per minute.

The plant runs continuously from 6
o'clock Monday morning until midnight
Saturday, every week, supplying elec-
tricity for light and power.

The report covers two months' opera-
tion, during which a total of 308,410 kilo-
watt-hours of energy were converted;
of this, 35,190 kilowatt-hours were used
in the plant and 273,220 kilowatt-hours
delivered. The cooling water for the en-
gine is used for other purposes after
leaving the jackets and it is therefore not
charged to the operation of the plant.
The scrubber water was not reported.

August 1, 1911

POWER

179

OPEKATIXO C^TS^PEH KILOWATT-norU CORRESPONDENCE
Cent

Fuel o.-ioTG Mr. Rushmorc's Operatins

I'roducer room laboi- 0.1585 ^ °

Oil 0.0141 Cnsts

Waste, etc 0.0024 '^UhLS

Engine-i-oom laboi- 0.055.5

Producer repairs 0.0127 I notice in the June 27 issue a criticism

Engine repairs omid ^^ ^^ ^^ ^^jj ^j ^j. Rughmore-s op-
Total ci.st 0.5048 crating costs, in which the item of profit

Plant "B" ''^•'O '^ brought in, the statement be-

One set of Loomis-Pettibone down- '"^ "^^^^ '^^^ ^ P'^"' °^-"" =°""' ^a^dly

draft producers supplying one 500-horse- consider investing ^25,000 in any branch

r .u „ „• „j . „„ of his busmess unless he expected to

power engine of the same size and type , „ ^

, » <, A " make some profit on the investment.

as in plant A. t j j ■. >j

Tu 1 . . „ rn u„ _„ „ ^„ A 1 can understand that a man would

The plant operates 10 hours a dav and

the figures apply to a period of 15 months. "°' =°"^"^" §"'"8 '"'^ business unless

Coal costs $4.53 per ton at the plant.. he expected to make a profit out of it, but

I hardly feel that he would go through

or-EKATIXG COSTS rEUKIl-OWATT-IIOVR his plant and pick out the different ma-

., , ,rf?i-n chines or branches of the business which

i^uel n.44ou

Water 0.0870 were most productive of profit, and de-
Oil 0.04H5 . 1, L- J^

Waste, etc 0.0335 vote all his money to these branches,

I'roducer-rooni labor Ri^9^ unless they were distinct and separate

Engine-room labor 0.20.>0 ' '^

Producer repairs 0.0243 departments, not interdependent details

Engine repairs "-•"" of his general business. A manufacturer

Total cost 1.2410 naturally has many departments in op-
Plant "C" eration, and none of these departments
^ ^ , . „ ., can be left out. In some particular de-
Two sets of Loomis-Pettibone pro- .„ ^ i • <• »u

. partment I can conceive of the cost

ducers, each of 2000 horsepower rating. . . . .u ^ »u ••

^ . , ,. J being very excessive, so that the ratio

Two twin-tandem engines with cylinders ■ o. „. . ,. . j- i n

„ , . , ^ ,„„ , •' of profit might be exceedingly small —

32x42 inches, rated at 1500 horsepower ■<■.-. ■ i,. v .u . .u- »• i

'^ in fact, it might be that this particular

each. Each engine has two main bear- j . . . i

^ . department, taken as a separate manu-

ings and drives an electric generator at - . . ■ i,. u i

^ . ,, , , factoring process, might show a loss

10/ revolutions per minute. Make-and- , i • .i, j •„ . .u c»

'^ while in some other department the profit

break ignition. ^-^^^^ ^^ ^^^^ g^^.^, j^.^^ ^,^,^1^ ^^^

oi'ekati.m; costs im;u KiLOWATT-iiotu justify the manufacturer in throwing out

'^ ''•'^" P J that department where his cost was great

Fuel 0.422 and increasing that department where

)\^^" 1 ■ ■ ■ ■;„• ?.-nU5 his cost was small, as he would then

Oil and waste 0.024 '

Miscellaneous supplies 0.015 have an unbalanced factory and the re-

Superlntondence 0.02G ,. ,, , . .- t . tu

IToducer -room labor 0.102 sults would not be satisfactory. The

Engine-room labor 0.063 manufacturer in making up his selling

I'rodueer repairs 0.024 t. k &

Engine repairs 0.004 sheets takes into account the sum of the

Electrical repairs 0.O05 . . ,, ,.«. , , . . .i.

-1 costs in the different departments, the

Total cost 0.688 cost of his selling, the overhead charges

_ ,,_„ and such other items as experience has

Plant "D ' • j- . j . u » t

indicated are necessary to be taken into

Two 400-horsepower producers with account, and adds to these a fair profit,
generators 8 feet Inside diameter, wet thus making his selling price. If his
scrubbers 8 feet diameter by 20 feet high power plant is a necessary part of his
and dry scrubbers 6 feet square by 3'< manufacturing, he considers this in work-
feet high. ing up his cost data and he would hardly

Three 250-horsepower vertical engines deem it necessary to go through each
each having three single-acting cylin- department and figure out that he must
ders 20x19 inches. Each main shaft make a certain definite profit in every de-
has five bearings and is coupled to an partment, as the salesmen of the lighting
electric generator. Speed. 230 revolu- companies insist he should,
tlons per minute. Make-and-break igni- Take, for instance, the heating plant
•'"n. in a factory purchasing power. Purely

The report covers three months' opera- as an investment, the heating plant of-

tion. The total running time was 1439 fers no return to the manufacturer which

hours and the total output 309,300 kilo- can be icmicd profit. It certainly is a

watt-hours. good investment, however, because it

The fuel Is No. I buckwheat anthra- enables his operatives to do their work,

cite, costing .S2.33 per ton. Can the manufacturer take his selling

oi'EKATiNo COSTS I'EK Kll.OWATT-uoiR organization and go through this and

Cent carefully examine into whether it returns

ri'i'r'wn.i.' etc 0 05-'' ^ profif on thc investment? In many

I'riKiiicrrwm labor 0.113.1 cases he could not get along without it.

Engine room labor 0,2fi4o , . ■ > ^ ■ •

Producer repnim 0.0240 " Certainly has to be taken into account

Engine repairs n.um („ making up his charges, but he can

Total cost 0.8020 hardly consider that he must make thc

same proportional return on money spent
in this department that he might out of
some other department where the goods
are manufactured. Must a manufacturer
consider that he should make a profit-
ratio return on the cost of his building
or the cost of his transmission appa-
ratus? If so, would he not rent it
rather than own it, and would he go to
the expense of elaborate buildings?

I should like to ask the sales agents
to justify their scheme that profit ratio
should be considered when figuring up
what it costs to produce power in a
manufacturing plant.

Henry D. Jackson.

Boston, Mass.

[Mr. Jackson's argument is just a lit-
tle out of line in one or two particulars.
His contention that a manufacturing
profit should not be added to the cost
of operating one's power plant in com-
paring it with the price of purchased
power is quite sound. The object of the
comparison is to get at actual relative
costs, unconfused with questions of the
hypothetical earning value of the money
invested. But his argument that the
cost of production in a manufacturing
establishment should not be considered
separately in departments or branches
and that an excessively expensive depart-
ment should not be dropped is an eco-
nomic fallacy. Many builders of gas
engines, for example, buy crank-shaft
forgings because they can do so for
less money than they could make the
forgings.

The weak point in including a manu-
facturing profit in the items of power-
plant operating cost lies in the assump-
tion that thc manufacturer could cer-
tainly make the money earn that profit
if he invested it in some other depart-
ment of his business instead of in the
power plant. No such certainty exists.
The current rate of interest is the only
charge that should be made against plant
investment; that should be made because
the money could positively be made to
earn it outside of manufacturing con-
siderations. Of course, depreciation,
taxes, insurance, etc., must be charged,
but these are charges against the equip-
ment, not against the money used to
buy it.

Mr. Rushmore's letter contained one
point which has not been noticed by any
of our contributors, namely, that when
an isolated plant is once installed, (he
interest on the investment goes on just
the same if the plant should be shut
down and central-station service sub-
stituted. Therefore, in considering thc
use of central-station service instead of
an isolated plant that is already installed,
interest on such part of the investment
as is not redeemable should be charged
as an item in the cost of the central-
station service. — Editor.]

189

POWER

August 1, 1911

Locating Keywaj' in Corliss
Valve Stems

When putting a new valve stem in a
Corliss engine it is easy to make a mis-
take in laying out the keyway, and un-
less it is accurately located it will be im-
possible to get the correct lap on the
valve without bringing the hook block
either too high or too low. If the key-
way is cut to bring the block too high
with the proper lap, the port opening
will be reduced from having to shorten
the reach rod from the wristplate to the
bell-crank lever; on the other hand, if
the block is brought too low, it will be
impossible to extend this rod enough to
bring the hook so as to engage with the
block at the point where it should hook

up-
After the new stem is placed in posi-
tion, the lever A (see illustration) can
be slipped on over the end of the stem in
the place in which it is to be keyed.
Then place the lever A where it belongs.
If the length of the dashpot rod C has
not been changed from its correct ad-
justment it will only be necessary to con-
nect it to the lever to bring it to the
proper position. If it has been changed
a straight-edge can be placed across the
hubs of the two levers as shown, using
a pair of dividers to measure the dis-
tance from the center of the pivot in
the end of the lever B on the crank end
to the bottom of the straight-edge. The
dashpot rod C on the head end is ad-
justed to bring the center of the pivot to
the end of the lever A the same distance
from the bottom of the straight-edge.
This will bring the angle of the lever A
right, providing that B is correctly placed;
if there is any doubt it can be checked
by removing the bonnet from the end of
its valve and seeing that the lap is correct
with the valve hooked up and the wrist-
plate in its central position.

The proper amount of lap to be given
the steam valves with the wristplate cen-
trally located Is, with a 12-inch cylinder,
■-It-inch lap; 14- and 16-inch cylinders,
f'V inch; 18-, 20- and 22-inch cylinders,
■H inch; .24-, 26- and 28-inch. f.-. inch,
and 30-, 32-, 34- and 36-inch cylinders,
1/2 Inch lap.

After the lever B has been properly
placed, hook it up and set the wristplate
in its central position. Then the valve is
put in its seat and turned until the cor-
rect lap is shown for that particular
size of cylinder. The keyway can then
be marked on the stem and any slight

inaccuracy can be overcome by adjust-
ing the reach rod.

In locating the keyway in an exhaust-
valve stem, place the new stem in posi-
tion, and slip it on the lever over the
end where it is to be keyed. Next con-
nect up with tiie wristplate rod and set
the wristplate. Then back up the lock
nuts on the rod as far as poisible and
unscrew the rod from the ends until
only about two threads are holding.
Count the number of threads and screw
the rod back half way into its mid-

LocATioN OF Keyway in Valve Stem

position of adjustment and then set up
the lock nuts. Next, place the valve and
turn it until it shows an opening corre-
sponding to the amount allowed for that
particular size of cylinder. The correct
amount of opening to be given for the
different diameters of cylinders is as fol-
lows: 12-, 14 and 16-inch cylinders, -/;
inch; 18-, 20- and 22-inch, j's inch;
24-, 26- and 28 inch, /^ inch cylinders
and 30-, 32-, 34- and 36-inch cylinders,
\i inch, ^ith the valve set for the cor-
rect opening the keyway can be marked
on the stem and then cut out; any final
adjustment is made by changing the
length of the reach rod from the wrist-
plate.

One should always bear in mind when
adjusting the steam valves for lap or the
exhaust valves for opening that the wrist-
plate must be in its central position as
indicated by the marks on the hub. Many
engineers have the mistaken idea that the
lap of the steam valves is measured with
the dashpots at the bottom. If the cor-
rect lap were given with the dashpots in
this position it would probably be found
impossible to get the engine to pass over
its centers on account of the excessive
lead.

When a valve stem is broken and the
piece containing the keyway is fitted back
to be used for a pattern to lay off the
position of the keyway in the new stem
it is almost certain to be wrong on ac-
count of the old stem having been more
or less twisted before it broke. This
will likely bring the keyway so far out
of its correct position that the difference
cannot be made up by adjustment. The
only remedy will be to either turn the
stem over and cut a new keyway on the
other side, or widen it and make an off-
set key. Either remedy makes a bungling
job and care should be taken to lay off
the correct position in the first place.

S. KiRLI.N.

New York City.

Removing a Broken Crank
Pin

The intermediate crank pin of a triple-
expansion vertical pumping engine is
shown in Fig. 1. One end of the pin is
forced into the crank B, by hydrostatic
pressure; the other end is bolted to the
block in the crank A, which is free to
move a little in order to take up any
difference in wear of the main bearings.

There are, therefore, two halves, the
side A, consisting of the flywheel and
the high-pressure crank on one-half, and
the crank B, consisting of a flywheel and
the low-pressure crank on the other.

The pin broke as shown, midway be-
tween the two crank disks, and was

Fic. 1

Fig. 2

covered by the crank boxes; thus the
two parts were held together. The break
was discovered when the box moved out
of the crank A and struck the pump rods.
The 12-inch crank pin was taken out of
the crank B as shown and a row of holes
was drilled around the outside diameter
next to the disk. A large bolt was
passed through the core hole and a
flanged pipe was put over the pin, as
shown at Fig. 2. Then a piece of iron
with a hole big enough to receive the

August 1. 1911

POWER

181

bolts was placed over the pipe and the
nut was tightened with a strong wrench
and a sledge, while a battering ram was
used on the other end of the pin. Of
course, the crank disk was heated.

H. R. Blessing.
Philadelphia, Penn.

Unnecessary Clearance Space

A few years ago, upon taking charge of
ai 18x36-inch Corliss engine, I found
that the cylinder head was put on with
heavy gasket tubing, such as is common-
ly used for manhole covers and other
rough work. This held the cylinder head
7 S2 inch away from the cylinder.

By replacing the gasket with sheet
packing 1,32 inch thick, the clearance
space was reduced 47.5 cubic inches.

The use of thick packing nearly
doubled the clearance in this case.

Roy W. Lyman.

Ware, Mass.

Raising a Steel Stack

The accompanying illustrations show
the progress made in placing a stack
100 feat high and 5 feet in diameter. The
stack was assembled before it was raised
and took the place of the two smaller
ones shown.

In Fig. 1 the gin poles are in position
and the method of guying them and of
attaching the blocks and tackle used in
hoisting the stack is also shown. The
stack is lying in a horizontal position on
the blocking ready to be lifted into posi-
tion.

Peculiar Stack Arrangement connections and the stack are shown

the accompanying illustration.
Back in 1866 there was built in the William Thomas.
northern part of Massachusetts a brick New York, N. Y.
stack, the base of which stands on a hill ___^

Saving C\lincler Oil

Many engineers allow the cylinder oil
extracted from the exhaust steam of an
engine to go to waste.

One engineer devised a scheme to
save the oil that passed through his open
heater, which was as follows: In the

Brick Stack with Stone and Tile
Smoke Flue

Method of Removing Oil from the
Separator to a Barrel

waste pipe that ran to the sewer he in-
30 feet higher than the grates in the serted a valve beyond a tee connection
boiler furnace. The boiler house is built and connected a drain pipe to an ordi-
at the foot of the hill, and, although the nary oil barrel.

J

1

Fig. 1

Fig. 2 Fic. 3 Fic. 4

Showing Stack in Various Positions While Being Placed in Position

The stack is lifted from the ground at
one end in Fig. 2, the necessary lifting
power being djveloped by two horses
and two windlasses, not- shown. The
stack is slung neai'er to the top than the
bottom 50 that the bottom end will, when
the stack has been raised to a suRlcicnt
hight, :ome practically over the brick
foundation that has been built for it.
Two views of the progress made are shown
in Figs. 3 and 4. In the latter view the
base of the stack is being swung toward
the brick foundation between the two gin
poles.

New York. N. Y. R. O. Warren.

stack has been in service for 45 years
and has had several additions built on
at the top, it is still in service. The stack
is 8 feet square at the base and is 70
feet in hight. It serves two boilers, one
of 70 and one of 110 horsepower capa-
city.

The interesting feature of this old slack
is the stone smoke flue, which is partly
underground. It is built from small
pieces of rock and mortar and forms a
flue 24 inches square. The larger boiler
is connected to the base of the stack
by means of a common tile smoke flue
that is 24 inches in diameter. These

Through one side of the oil barrel, 8
inches from the top, a short length of
pipe as placed, having a lock nut on
each side of the barrel stave; rubber
washers were used to make a tight joint.
On the inside of the barrel a pipe ex-
tended to within 3 inches of the holtoin.
On the outside a pipe was connected for
an overflow pipe that led to the sewer.
The oil that was trapped in the oil sep-
arator, together with the condensed
steam in it, passed to the barrel. As the
oil came to the top it was easily removed
and all excess water ran to waste.

In this plant it had required 3 gal-

ISJ

POWER

August 1, 1911

Ions of cylinder oil per day, costing 60
cents per gallon, to lubricate the cylin-
ders of the engines and auxiliaries.
After the new system had been put in
operation, one gallon of oil was suffi-
cient for all requirements. This made
a saving of ;.i438 per year with prac-
tically no outlay in first cost or in the
operation of the system. The engineer
also obtained the purest kind of cylin-
der oil, which was used to lubricate the
auxiliary machinery of the plant.
Brooklyn, N. Y. A. R. Blake.

Repairing High Pressure Hose

I was once called upon to do a hurry-
up job on a high-pressure water hose
which was being used in connection with
a water-turbine boiler-tube cleaner with
water at 150 pounds pressure per square
inch.

The hose had a split about 2 inches in
lengtU. I did not want to cut the hose
off as it would be hard to hold together
under the working pressure. I there-
fore decided to split the hose to a dis-
tance of about 5 inches on each side and
then insert a nipple about 10 inches
in length, first pushing it into the hose
on one side of the split until the other
end would enter the hose. Then I cen-
tered the pipe in the cut section. This
gave me two sides of the hose and kept
it from pulling apart.

The next move was to clamp each end
to make it water tight. I had no clamps
that would fit, so I put on clamps of
wire with an instrument I made, its
application being shown in the illustra-
tion.

When the nut B is screwed up on
the threads on the bolt A it carries the
cross arm C with it, drawing the wire
tightly around the hose. A V-shaped
recess is filed on the head end of A to
receive the bight of the wire, as shown
in the illustration.

Measuring Water without a
Meter

The amount of feed water pumped into
a boiler is a point of interest to the en-
gineer. If there is a water meter in the
pipe line this may be determined, but
such an instrument is never correct and
a coefficient must be applied. To render
the situation more difficult the coefficient
varies with the speed of the meter and
also with its age.

Assume that a 50-foot pipe line is
supplying a boiler with water. The
amount of water flowing through the pipe
may be determined in the following man-
ner: Tap a 'x-inch iron pipe into the far
end of the supply pipe A in Fig. 1. Run
this ;i-inch pipe along the larger one
to any convenient point near the boiler
or other outlet, and connect it to a U-
tube having a scale graduated in inches.
Also connect the U-tube to the point B
in the supply pipe and half fill the U-
tube with mercury.

When water is flowing in the supply
pipe there will be a drop in pressure
between the points A and B, causing the
mercury to be elevated in one leg of the
U-tube and depressed in the other. The
pressure drop varies with the velocity
of flow and it is this fact which makes
it possible to determine the volume of
water passing through the pipe.

First, however, the arrangement must
be calibrated, which means maintaining
the difference in pressures constant for
a definite period, say 10 minutes, and
collecting the water in a barrel and

number of different pressures are taken
and the water collected for each. The
results should be plotted as in the curve
(Fig. 2).

Such an arrangement is not expen-
sive, but the chief advantage is that
when once calibrated it may be depended
upon for accuracy at all times. Another

^Zi

/

/

3

Ea4

/

/

}

/

/

/

1 1.2

/

/

o
|Oii

/

/

o "'*

/

cr

/

0 0.4 0.8 \1 1.6 Za 2.4 2.8
Gallons per Minute '■~~"

Fig. 2. Quantity-pressure Curve

feature is that it is not affected by hot
or dirty water or chemicals. The dis-
tance between A and B should not be
less than 25 feet, but need not neces-
sarily be straight.

K. H. Anderson.
Chicago, 111.

Close Crosshead Clearance

One day a party of engineers visited
my plant and my oiler was in high glee
because he had a couple of engineers

Temporary Connection
Used only during

Fig. 1. Arkancement of Velocity AIfier

Miriioi) 01 Ri-:pairing Hdsi-

When the wire is drawn tightly enough
the tool is pushed forward, thus hook-
ing the two ends over the bight of the
wire.

If wire of a high tensile strength is
used and a little care is exercised in get-
ting the wires straight, a permanent job
is usually the result. A great deal de-
pends, of course, upon the workmanship.
W. Dennis.

Attleboro, Mass.

weighing it. For this purpose cut in at
some point beyond B with a tee as shown.
C is a three-way valve which is used so
that while the desired difference in pres-
sures is being obtained the water may
be flowing through one opening of the
three-way valve and into the sewer. When
the desired pressures are secured the
handle of the three-way valve may be
turned and the stream discharged into
the empty barrel which has previously
been weighed. At the end of the 10-
minute interval the three-way valve
handle is again turned and the stream
directed into the sewer. In this wav a

who would listen to him. He was show-
ing them something about the crosshead,
and as he was feeling the pin and look-
ing around at* the same time, a finger
was caught and amputated by the cross-
head, which traveled ver\' close to the
bored-out part of the frame at one end
of the stroke. I afterward measured
it and found it only cleared by 1 16 inch
at the point where the finger was clipped
off. I put up a guard consisting of wire
netting fastened with cap screws to pre-
vent a repetition of the accident.

D. L. Fagnan.
New York Citv.

August 1, 1911

POWER

One on the Professor

The method recently described in
Po\x ER of how to tell wrought iron from
cast iron calls to mind an incident in
an experience covering many years in
the mechanical-engineering field.

A few years ago while I stood in
the machine shop of an institution which
teaches the engineering professions,
when the professor in charge of the de-
panment of mining engineering and
metallurgy came in, picked up a round bar
of cast iron about 1 ' _■ inches diameter
and about 12 inches long, from which the
molding sand had been cleaned.

He walked over to me and asked:
"What kind of steel is this?" Those
familiar with cast iron in the rough, as
it is called when the sand has been
cleaned off and it has not been ma-
chined, distinguish it from the other
metals by a peculiar coating called
"scale." When the casting has been
"tumbled" this coating has a shining
gray color. When cast iron has been
machined it is easily distinguished by
its porosity.

To the professor's query I replied:
"That is not steel; it is cast iron," and
I picked up three other short bars, one
each of wrought iron, low-carbon steel
and high-carbon or tool steel. He asked
me to give him a small piece of all four
metals, which I did. He took them
away with him.

In a few days he came in again and
said the metals were as I had told him.
He then remarked that I had picked the
bars from a box in which they were all
mixed together and asked how it was I
could so readily tell each from the other.

I then picked up another piece of cast
iron, and with a hammer and chisel be-
gan to chip off pieces, at the same time
calling his attention to the brittleness of
the chips, to the minute porous holes,
the "scale" and its peculiar appearance
on a casting that had been "tumbled"
and on one that had not.

I treated the other metals in the same
way, explaining the sand seams in
wrought iron and the homogeneous
structure of the steels and the coatings
of each. He thanked me profusely.

The next day the junior students told
me that the professor had very learnedly
discussed "the physical properties, char-
acteristic appearance and molecular
structure of cast iron, wrought iron and
low-carbon and high-carbon steels."
A. P. Mann.

Brooklyn, N. Y.

Comment,
criticism, suggestions
and debQte upon various
articles. letters and edit-
orials which have ap-
peared in previous
issues

Indicator Diagram Defects

In a recent issue the accompanying
diagrams were offered for discussion.
The diagrams were taken from a Porter-
Allen engine. The man who submitted
them said: "The irregularity of the dia-
gram at the point of admission has puz-
zled the engineer in charge, particularly
as several different indicators have been
used on these engines. Why do not the
same defects show on both diagrams?"

Being familiar with the Porter-Allen
engine I offer the following explanation:
When the length of the connecting rod
equals six crank lengths, as it does in

Showing Irrec.ular Steam Line of
Head-end Diagram

most of these engines, the difference in
the velocity of the piston in opposite
ends of the cylinder is considerable, be-
ing less at the crank end and greater
at the head end. The difference in veloc-
ity averages 20 per cent, and between
the commencement and termination of
the stroke reaches the great amount of
40 per cent.

Now the driven arm of the link which
gives motion to the valves is also equal
in length to six eccentric cranks and its
angular vibrations coincide in degree as
well as time with those of the connect-
ing rod and so it receives a motion coin-
cident with that of the piston, giving to
the valves in opening and closing their
ports different velocities, greater at the
head end than at the crank end, corre-
sponding to the difference in velocity of
the piston.

The serrated steam line of the diagram
taken from the head end of the cylinder
is caused by the sudden impact of the

steam against the piston of the indi-
cator which makes the pencil bar of the
instrument vibrate above and below the
true steam line.

The reason why the "defects" are not
the same on both diagrams is because
the admission valve and piston move
more slowly at the crank end; conse-
quently there is not such a sudden im-
pulse given to the piston of the indi-
cator as to cause excessive oscillation of
the pencil bar before it settles on the
true steam line.

I would suggest an increase of com-
pression at the head end to a point a
little higher than that shown at the crank
end; then a much slower motion will
be imparted to the pencil bar of the in-
dicator during more than one-third of its
motion; therefore, its momentum would
be much less than that produced by the
sudden opening of the admission valve
when the pencil is bordering on the at-
mospheric line.

With the above adjustment a higher
pressure should be realized at the head
end, also a more nearly uniform steam
line.

,1. W Parker.

Clinton, Mass.

Boiler Settings

On page 67 of the July 1 1 issue, Mr.
McGahey says that he has filled the air
space provided in his boiler settings for
insulation purposes with sand in order
to retard the cold-air inflow when cracks
develop in the walls. He is quite right
in doing this, but the better results in
his furnace are not, as he may think,
entirely due to stopping up the cracks.
While sand will help to stop up the
cracks there are other ways of accom-
plishing this. The principal thing Mr.
McGahey did was to retard the heat
by radiation, which is far greater than
any loss because of cracked boiler set-
tings unless, of course, the settings are
in extremely bad condition.

Mr. Dumar. in his article on page 63
of the same issue, states that he packed
the air spaces in his bofler settings with
asbestos, and has provided as far as
possible against loss by radiation.

I would refer all those who are now
flghting to hold their jobs against the
central station to a bulletin issued by the
Bureau of Mines. Department of the In-
terior at Washington, entitled, "The
Flow of Heat through Furnace Walls."

The matter of heal losses by conduc-
tion and by radiation is gone into very

184

POWER

August 1, 1911

thoroughly in this bulletin, which also
gives some interesting results of tests
and investigations made alofig this line.
The bulletin may be had without charge
by applying to the director of the Bureau
of Mines.

The conclusions arrived at are that a
solid wall is a better heat insulator than
one of the same thickness havirrg an air
space, particularly if this air space is
close to the furnace side ot the wall
and if the furnace is operated at high
temperatures. It is further stated that
if it is desirable to build the walls in
two parts, to prevent cracks from ex-
pansion, etc., the space between them
should be filled with such loose material
as ashes, sand or crushed brick which
will offer a higher resistance to the flow
of heat than an air space.

As Mr. Dumar states, too luuch atten-
tion cannot be given to the boiler set-
tings because proper construction means
a minimum loss of heat and this again
means lower steam costs, all of which
is ammunition for the small power-plant
engineer to fight with against the cen-
tral station.

EvERARD Brown.

Pittsburg, Penn.

Rolling Boiler Tubes

The letter by S. Kirlin in the July 4
issue on the subject of rolling boiler
tubes contains several good ideas.

In my estimation there is a proper
time to roll boiler tubes, and proper
persons should be set to do the rolling.
Speaking of tubular boilers, it is my
opinion that if the boilermaker, who is
really the proper person to do the work,
will look over the boiler as soon as the
furnace and combustion chamber have
become sufficiently cool and before the
boiler is emptied, he will get a more
intelligent idea of the necessary work to
be done and will be able to determine
without question just which tubes are
leaking and roll them. In tubular boil-
ers with the rows of tubes arranged ver-
tically a tube in one of the top rows
only luay leak and the water and dirt
from it may run down over the lower
tubes. To the inexperienced and not
thoroughly practical man there will ap-
pear to be an immense amount of
trouble, especially if the boiler has been
emptied. A great many men cannot start
rolling at the topmost leaks and work
downward, carefully noting the effect
of their work. -According to my obser-
vation it very often happens that many
tubes that never have leaked are rolled
unnecessarily as a result of this inex-
perience or the fact that the one who
did the rolling did not make note of
the work before the boiler was emptied
or after it had been washed out and re-
filled. I am not advocating work on
boilers under pressure when I speak of
working on them before being emptied.

Men often make the mistake of not
having the inner surface of the tube
perfectly clean. Others do not have
their expander set so that the rolls will
not protrude too far into the tube. Others
use a too heavy hammer and slam the
pin in entirely too hard the first time.
It is easy to ruin a tube in just this way
if they only knew it. It is very nice
if a boilermaker has a correct idea of
the thickness of the tube sheet or head
upon which he is working in order that
he may set his expander collar properly.

Rolling tubes in any kind of boiler
should never be done by guesswork.
Carefully note your leaks, roll the tubes
just enough to stop them and remeiB-
ber to leave enough material to work
on in case a leak should occur in the
same place at some future time.

T'JOMAS M. Sterling.

Middlebranch, O.

Massachusetts License Laws
and Examiners

When I read articles from time to time
advocating the licensing of engineers
and firemen in other States, and holding
up the present unjust system existing in
this State as standard and worthy of all
acceptation, I am convinced that the
knowledge of this system is very limited.
It is my purpose to set forth the condi-
tions as they are found to exist by the
applicant for license.

As the law explicitly states that the
applicant shall be given a practical ex-
amination, let us see what he gets.
An applicant for a second-class engi-
neers' license was recently rejected after
having taken an examination of which
the following questions are typical:

"State the comparative merits of the
various makes of steam-engine indi-
cators." This engineer expected to be
examined on the practical use of the in-
dicator and the reading and criticism of
indicator diagrams, and was prepared to
answer the questions, but unfortunately
he had never made a study of that phase
of the subject and so was considered
practically ignorant of this very important
instrument.

"Design a double-riveted butt-strap
joint for the greatest possible efficiency."
An operating engineer with a second-
class license who would be called upon
in practice to design a boiler joint, or
who would be considered an authority
on the subject by the average employer,
would indeed be a curiosity.

"Design a double-riveted lap joint."
.Ml dimensions are given, including the
diameter of shell. 60 inches. This is a
catch question, the catch being in the
diameter of shell, which by law is limited
to 36 inches for this style of longitudinal
joint.

An applicant for a third-class license
was recently given an examination con-
sisting of questions like these:

"What limits the number of stays in
the throat of a Heine boiler?" This
question properly belongs to the consult-
ing engineer or boiler manufacturer.

"If you were retubing a Babcock &
Wilcox boiler, what precaution should
be taken regarding the lower tubes?"
Who ever heard of a third-class operat-
ing engineer, in this State, retubing a
boiler? I have worked in eight different
plants, some of them large and uptodate,
but none of them contained a tube ex-
pander. I do not know of any insurance
company tHat will vouch for a job of
boiler retubing unless done by a com-
petent boilermaker and there are very
few of them even among the best chief
engineers.

After an applicant has visited the ex-
aminer a sufficient number of times, spent
a dollar for each rejection, and has
gathered up all the catch and trick ques-
tions, he usually gets his license. In
the meantime he loses from S12 to 815
in time lost, carfare and incidentals,
and has the equivalent of SI; this is the
financial injustice of it. The law should
read that the examination (?) fee of SI
be refunded if the applicant is rejected.
A second-class engineer was asked only
two questions at the time of his second
visit which he could easily have answered
at the time of the first one.

This incident led me to suspect that
a clause in the law covering the pro-
vision just mentioned might decrease the
number of examinations, or even in-
crease the number of licenses granted.

Technical and catch and trick questions
and those in advance of the grade of
license applied for constitute 50 per cent,
of the questions asked. In short, the
manner in which deserving applicants
are being turned down has the appear-
ance of conspiracy in office against the
engineers and firemen. But why? Does
the supply of intelligent, capable engi-
neers exceed the demand? The employ-
ers claim that engineers and firemen of
the right kind are hard to obtain. Have
the first-class engineers of the State con-
spired to keep the assistants down be-
cause they fear the natural competition
for the higher-priced jobs? This looks
logical, but even if true, why should
the examiners cooperate with them ?

These are the questions which the as-
sistant engineers of the State are discus-
sing. The tendency is not to find out
what the applicant knows but what he
does not know, and to throw^him down
if possible.

If the examiners' conception, of a prac-
tical examination is the true interpreta-
tion of the law. then a change in the law
or its total abolishment is the only hope
of advancement for the present assistant
engineers. I am personally acquainted
with a chief engineer whose- practical
knowledge of boilers can be judged froin
the fact that he never did a day's firing
in his life, and also an assistant who for

August 1. 1911

POWER

185

seven years had charge of a second-
class plant on a special license. This
man's experience as fireman and engineer
covers 14 years and he has been re-
jected several times for a second-class
license. If these men were given a
practical examination, their positions
»x)uld be exactly reversed.

When applicants for second- and even
for third-class license are asked ques-
tions that make their chief engineers gaze
dumfounded and exclaim, "We do not
know," there is something wrong; when
men who have had charge of large power
plants for years candidly make the
humiliating statement that under the
present conditions they could not get a
third-class license, there is something
wrong. I know that these sentiments
are held by men all over the State, so
let us hear from them. I hope to see
(his vitally important matter liberally
discussed in the columns of Power.

While this injustice is practised in-
divdually, it is nevertheless a common in-
jury; let us make it a common cause
and do something to better the condi-
tions. We should organize and make a
common appeal to the legislature through
our representatives. We help pay their
salaries, but how many bills are they
called upon to champion in our interest?
I understand that at the last session we
had a bouquet handed to us in the shape
of house bill 310, and we were just
ready to smile, and bow our thanks
when we noticed that it deprived us of
our right to appeal, so you see there
was a trick in it. Just so long as this
system of examinations holds sway, in-
cidents like the Pittsfield disaster will
continue to shock the public and the
practical engineer will remain the as-
sistant.

J. A. Lkvy.

Greenfield, Mass.

Alton Boiler Explosion

Referring to the boiler explosion de-
scribed in the June 27 issue, I agree
with Mr. Rockwell as to the cause. I
had a similar case myself. My four
boilers were of the same dimensions as
his, carrying 125 pounds gage, were con-
nected in the same manner to a 14-inch
header, and the accident also occurred
at 6 a.m. In my case the assistant en-
gineer and fireman came on watch at
5:45 a.m. The assistant's duties were to
blow down each water column and see
whether there was sufficient water, and
then to get the engines ready.

On this morning I got a telephone call
at 6:15 a.m. that No. 6 boiler had ex-
ploded. On examination I found the fire
sheet down from the flange to the girth
seam across the whole width of the
boiler. This bag was split for about 14
Inches at its lowest point lengthwise of
the boiler. My reasons for thinking that
there was no water in the boiler are
that the explosion occurred within 15

minutes after making up the fire. The
brickwork of the furnace was not dam-
aged, the grate was not disturbed and
some of the green coal fired remained
on the wings. The tubes had been rolled
three days before the boiler was washed
out, under my own supervision, but the
insurance inspector gave it as his opin-
ion that scale caused the explosion and
his word was taken in preference to my
proof to the contrary.

Comparing the two explosions, while
a lot of other damage was done in Mr.
Rockwell's plant, in mine nothing out-
side of the boiler itself was injured.
There is a wide difference in the result
of both explosions. I think this goes
to show that conditions must have dif-
fered w-idely at the time as the slight
damage done in my case goes, with the
burnt appearance of the shell, to show
that there was no water. In Mr. Rock-
well's case the amount of damage shows
very clearly that there was water in the
boiler.

William Chaddick.

Chicago, 111.

Cutting Packing over Wooden
Mandrel

In the issue of June 27, there is a
communication from William L. Keil con-
cerning the cutting of packing on a wood-
en mandrel. The following hints may be
of practical assistance to some engineers
in this connection:

As a rule, the space between the ends
of the ring should be about ]/» inch for

Cut on dotted Lines

JWZZ

Packing Nailed on Mandrel and
Scribed for Cutting

every inch diameter of rod. Using that

as a basis, the following sizes of wooden

mandrel about which to coil packing for

various sizes of rod will be suitable:

Diami-ter of Diaimtir of

Rod .Mandril

1 iS

11

t ■■!((

Take the coil of packing and nail one
end on the mandrel. Spiral the packing
tightly and then nail the other end.

Scribe two lines parallel to the axes of
the mandrel and about 134 times the
thickness of the packing apart. By cutting
obliquely between these marks as scribed,
the packing will be cut into rings which
are scarfed and which will have just
about the right allowance for endwise
expansion.

By following these instructions an en-
gineer can cut his own rings accurately
and save the extra expense involved in
buying rings already cut. Before the
rings are inserted they should be dipped
in cylinder oil and placed in position so
that the open spaces are staggered and
do not fall one on top of the other.

W. E. Sanders.

Trenton, N. J.

Poor Draft

After studying L. P. Cotton's troubles
because of poor draft, as described in
Power of July 4, I do not approve of
the stack being placed off at one side.
As it is, boiler No. 1 should have the
strongest draft according to the design
of the header and the chimney. A design
of this type often causes trouble in main-
taining the proper combustion under
Nos. 2 and 3. If the stack were closest
to No. 2 I believe Mr. Cotton would have
no further trouble.

My advice to Mr. Cotton is not to carry
a thick fire; make it light and fire often.
William T. Hurd.

Bellefontaine, O.

Isolated Plant versus Central
Station

Aluch of what Mr. Brown says in the
June 20 issue of the Isolated Plant is
quite true. I differ, however, with his
assertions regarding the effect which the
various articles in Po\x er may produce.
It is my opinion that the full discussion
of this matter in the columns of Power
will serve to save many a plant in which
the engineer has been asleep.

Not long ago 1 went into a plant where
the engineer is not much of a reader.
His apparatus was doing good work and
no doubt he was producing power cheap-
ly. But — some day the central-station
man will be around and offer to sell his
concern power for 6 cents, perhaps, and
it will take this engineer six weeks or
more to find out that he is producing it
for 3 cents. In the meantime the cen-
tral-station man is getting acquainted and
may be actually putting his offer through.

Mr. Brown brought out a good point
when he referred to the willingness of
many owners to spend large sums for
a good equipment for using outside
power while had they been asked to spend
a reasonable amount on the private plant
to increase its efficiency they would have
refused with emphasis.

C. R. McGahey.

Baltimore. Md.

POWER

August 1, 1911

Friction Load Diaj^rams

The friction-load diagrams of an 8x10-
inch Ames engine taken by Mr. Small-
wood and shown in the June 25 issue
are readily explained by the construction
and action of the governor. Fig. 1,
herewith, shows in diagrammatic form
ihe positions of the governor parts at
Head- and crank-end centers, also at
the points of greatest and least valve
travel. The points P and P' are the gov-
ernor-pin positions at the head- and
crank-end centers respectively; e and e'
are the eccentric-pin positions at great-
est and ; and I' at least travel. The
points R and R' mark the rocker-arm pin
positions. The eccentric pin moves
along the arcs a and a' when the governor
is being opened and closed and the ec-
centric-rod head swings through the arcs
4 and A'.

circle, Fig. 1, it will be 30 degrees be-
hind the crank, or have 150 degrees in
advance as the motion is reversed by the
swivel arm, and the valve will have 4J.4

Diagram of Valve-cear Action

It will be noted that the deviation be-
tween the arcs A and a' is considerably
greater at the crank end than at the head
end and where the valve is set to have
even lead on both centers while the gov-
ernor pin is in the position of greatest
travel, it must have considerably less
lead or more lap on the crank end when
it is on or near the point of least travel
and the engine will give an uneven fric-
lion-load diagram as in Mr. Smallwood's
'-case.

I do not know the governor and valve
dimensions of an 8x 10-inch Ames engine
but remember those of an 18xl8-inch,

Fig. 2. Zeuner Diagram

and assuming them to be proportionate
will substitute them as they fit the case.
The valve has 4 inches of steam lap,
;4 inch of exhaust lap, 5V^ inches great-
est and 3 If; inches least travel. Sup-
posing that under friction load the gov-
ernor pin takes the position in the middle

AJmiss':on: — \ V ^

Fig. 3. Zeuner Diagram Applied

inches of travel. The Zeuner valve dia-
gram, Fig. 2, drawn for this motion of
the valve, gives the events, provided the
valve is set to have even lead at this
position of the governor pin. It is not,
however, and the lap circles will have
to be moved a proportionate distance to-
ward the crank end (about 5/64 inch on
a full-size diagram) with the result that
there is hardly any admission, later com-
pression and earlier release on the crank
end, while there is more steam, early

Fig. 4. Reproduction of IVIr. Small-
wood's Friction-load Diagrams

compression and later release on the
head end, as in Mr. Smallwood's dia-
grams, which are reproduced. The steam
line of the crank-end diagram drops ver-
tically because there is no admission
while the piston is moving away. The
very short term of admission and the re-
expansion of the compressed steam keep
the line from continuing vertically but
cannot prevent its falling below the com-
pression curve. The head-end compres-
sion is very early and the engine is
using but little steam. The pressure in
the exhaust line is therefore low when
the crank-end release occurs, as shown
by the drop at R.

Automatic engines with pivoted ec-
centrics cannot be adjusted to give even
diagrams at all loads. There is always
some difference between the full- or no-
load diagrams, depending on the design
of the governor.

Z. Werner.

Chicago, III.

Cutting Packing

In the June 27 issue, I read with in-
terest, Mr. Keil's method of cutting pack-
ing. I have also read every one of
"Old Bill's" talks on packing, and some
of them several times.

I get the same results in cutting pack-
ing another way by making a gage as
follows:

Take a piece of dressed pine 154x4x27
inches long; on this fasten two strips
of the same material dressed to V^xY^
inch and space 'lJ inch apart. After
obtaining the length of packing required
for a ring, measure this length out on
the strips and mark each end with a
bevel, putting a stop in on one end;
then with a saw cut through the strips
to the base.

To cut packing simply lay it in a
groove, cut a bevel on the end, push
the packing against the stop and then
cut it off at the bevel next to you.

I mark the board thus: "Six rings Ji
inch, square flax, for 5x8-inch triplex
pump."

My method of packing is: After pull-
ing old packing, cut six rings, graphite
three of them, put the first one in with
the joint toward me; then one with joint
from me or on the other side of plunger.
Next, the third one with the joint toward
me again. Cut open three rubber rings
and break the joints opposite to the flax.
When the three rubber rings are in, then
put in the other three flax rings. I use
a tool to push the rings down into the
box. Put the gland down and run the
nuts up with the fingers. The packing
will leak for a short time but will soon
become tight; when it leaks again it is
time to repack. I never follow up with
other rings or use a wrench. This kind
of a job will hold pressures up to 700
pounds per square inch.

J. P. COLTO.N.

Ohio City, O.

Fitting Gaskets

In a rect-nt number a correspondent
describes a case of trouble with rubber
gaskets blowing out. In several similar
cases I have prick punched one of the
surfaces between which the gasket was
to be fitted. The gasket material would
work into the hales and consequently the
gasket would hold better. In each in-
stance this has overcome the trouble ver>'
satisfactorily.

When it comes to tightening up bolts,
many men are governed not by the
strength of the bolt but by the length of
the wrench arJ their own strength. More
wrecks are caused by overstrained bolts
than by bolts that have not been set
tight enough. It is only the real engineer
or machinist who can tell by the "feel"
when a bolt or nut is properly tightened.
J. O. Benefiei..

Anderson, Ind

Au2ust 1, !911

P O W E R

Issued Weekly by

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Contents

Richmond's .New Muuiciiiii! I'lant

Iti'HTniinint' the Valii" of a H.t.ii

The Combu-ition of Town Itefuse

Test with Oil Fuel

Pesign of Steam Power I'lants

Smoke Prevention in I^argo Power St;i

164

tlons

.V|ii)roxlmate Kule for Receiver Pressure

for Ki|ual Loads 17;;

(ip'Tatlon and Connections of Alternatois

Working in Parallel I74

Mr. C'ran"'s Switchboard I77

Ailachment for Running on Low Grade

I>l»llllates ITS

fiperatlnt Coiita of <;as Power PInnt.s. . . 17.S

Mr. Ruxhmore'x Operating Coits 17'.i

Practical I>'tters :

I^catlD); Keyway In Corll.ss Valve
.SteinR. . . .Kemovlng n Broken Crank
Pin .... I'nnecesKary < learance Space
.... Raising a Sleel Stack .... Pe-
culiar Slack Arranuemenl. .. .Saving

Cylinder Oil Rep.iirlng High

Preminre How. . . . Mensiirlng Water
without a Meier. .. .Clone Croashead
Clearance 1H0-18U

I'Wcuiiiilon Lellers:

One on the Profemor. .. .Indicator
Iilngrnm Ix'fecln. .. Roller Settings

Rolling Roller TuIk-k, . . .Ma.«iia-

rhii»otf<< I,lren«e I>iw« and Ex-
aminer*. ... Alton Roller RxploHlon
....Cufiing Parking over Wooflen
Mnndrel. . . .poor Krnfl. . . .Iiuilflted

Plant verfinii Central Sintinn

Friction Tjnnfl Dlaernmn. .. .Cutting
Parking Fitting Oafiketa iss-isn

Fdllorlfll!! 1«7.1R«

Comlilned Vaeiium and Oravlty Refiirn

llenllne System jno

I>>glslatlon on CompulBorr Ventilation.. 10?

Weatlnghotiae Automatic Bleeder Turbine lOH

Take no Cliances

In the issue of July 4. a correspondent
attributed the flywheel explosion in the
power station at West Berlin. Mass., to
the overspeeding of one of the engines.
The engines were run condensing at 88
revolutions per minute and were belted
to direct-current generators of about 200
kilowatts capacity. The governor pulleys
were not provided with flanges to pre-
vent the governor belt from running off.
It was assumed that the explosion may
have b»en caused by the safety device
failing to operate.

While the immediate causes of fly-
wheel e.xplosions are various, and often
difficult to determine, it is not wide of
the mark to assert that either neglect
or carelessness is usually the ultimate
cause.

To examine the governor gear daily,
to make a hammer lest of and inspect
the flywheel frequently, is the practice
of but few engineers. This is good
"life and property" assurance.

Few men are willing to take chances
in the ordinary walks of life; they regu-
late their hours of working, eating and
sleeping; when the machinery of the
body appears to be out of gear it is
given a thorough inspection and tested
for its efficiency and safety. They are
constant in its care and watchful, day in
and day out; they cannot afford to take
chances.

Wherever there is even a possibility
of accident due to weakening of parts
or inoperative appliances, the daily
vigilance of the engineer is the price
of his safety and that of the property
committed to his charge. It may be
that a daily rigid inspection for years
would fail to reveal a crack or break,
but no engineer can be confident whether
everything is as it should be until he has
made a thorough inspection and test.

A reliable report of the flywheel ex-
plosions in the United States for the
year 1910 states that there were 67 ac-
cidents in which 16 men were killed and
28 were injured. The great loss of
property, wages and profits cannot be
approximated.

If is appalling to think what the loss
of life and property might be because
of an explosion in a plant in a thickly
populated section of a city. In the West
Berlin power-plant explosion a piece of
rim 7 feet long and weighing nearly a

ton was hurled through the roof of the
station and landed 400 feet away, and
the outboard bearing was torn from its
bed and driven through the brick wall
of the building. While there was no
loss of life in the explosion, there prob-
ably would have been had the plant been
in a large city.

The figures given in the foregoing re-
port should make the thoughtful and
careful engineer sit up and take no
chances.

Value of the Hammer Test

Not long ago a locomotive type of
boiler carrying one hundred and seventy-
five pounds pressure exploded within five
weeks from the time it was inspected
and guaranteed to be safe for operation
at the pressure given. The initial rupture
occurred in the firebox, the side of
which was torn from some forty of the
staybolts, fifteen of which were found
to have been broken for some time be-
fore the accident.

It is impossible to determine the con-
ditions existing in the narrow space of
the water leg of a locomotive boiler and
the inspector is obliged to rely upon the
meager information furnished by his
hammer as it is applied at different
points.

Thin spots in a boiler plate may be
detected by a skilled inspector with the
hammer if there is a serious wasting
and loose or broken stays reveal them-
selves. But when the stages are
only cracked the most expert may
be deceived if guided by sound
alone. It is a comparatively easy mat-
ter to drill small test holes in a plate
where weakness is suspected, but it is
not so simple with a large number of
staybolts in position in a firebox. These
stays are subject to a bending effect at
every change of the temperature of the
water, owing to the difference in expan-
sion between the outer and inner sheet
which finally breaks the bolt.

For this reason hollow staybolts are
becoming more common in the construc-
tion of firebox boilers and this explo-
sion emphasizes the desirability of ex-
tending the practice.

It is undeniable that the hammer test
in places which the eye cannot reach
is not conclusive and it should be sup-
plemented by the hydraulic test for
boilers of this type.

188

Steam Plant Design

When we see a steam plant, especial-
ly a new steam plant, we conceive the
designer studying each element and se-
lecting from those available the type
most adapted to the conditions in hand.
We put ourselves in the engineer's place
and try to determine the scientific con-
siderations which led him to use such
and such an element here and there. And
sometimes the profundity of the problem
is beyond our depth.

As a matter of fact the considerations
which lead to the form and character
which steam plants take on are usually
not to be found in books upon engi-
neering nor to be explained by any of
the tenets of the profession.

Few plants are designed by engineers
with unrestricted freedom to produce the
station which will turn out power at the
smallest cost. They are mostly com-
promises with restricted space, financial
limitations, and. worst of all, with the
necessity of putting in this or that, or
warping the design to allow of the use of
thus and so to please a director, a stock-
holder or a customer. Instances are not
wanting where the judgment of the en-
gineer has been warped by the fact that
he had an interest in the sale of some
of the apparatus. If his agency is ac-
knowledged and open the client accepts
the probability of getting his goods if
they will work in, but the professional
designer should have no underground
connections which may influence his de-
cision.

When, therefore, you attempt to an-
alyze a plant and find it difficult to ac-
count for, do not dig too deeply for
abstruse engineering reasons on the one
hand, nor question the good sense of the
engineer on the other. If you had been
in his place you might have found "the
ties that bind" just as aggravating as
he did.

Precedent

The average man is a conservative in-
stitution. Usually, before he will try
something new he wants to know who
have done the thing, what success they
have had, how much it cost, et cetera.

Conservatism seems to be most viru-
lent in the field of engineering. More
really idiotic practices than you can
readily enumerate endure simply be-
cause most men are afraid to attempt to
reason for themselves and break away
from the precedents established by
their forefathers. Salesmen appreciate
the truth of this perhaps more than the
men of any other class. Ask any man
who is trying to sell some device which
is based on a new idea or which de-
parts a little from common practice what
his opinion is of this human inertia.

What applies to the introduction of
new apparatus applies even more exten-
sively to the introduction of new meth-

POWER

August 1, 1911

ods. Many a man persists in doing a
thing in a certain way for no more sat-
isfactory a reason than that he was
"learned to do it that way."

Take, for an example, the matter of
furnaces for fire-tube boilers. Few who
have studied the subject to any extent
will deny that the distance between the
grates and the boiler shell should be
made much greater than it commonly is
made. Also, that this distance should
vary with the nature of the fuel and not
with the size of the boiler or grates or
something else. Yet, very little change
has been made in the furnace design the
precedent for which was established in
the long ago when knowledge of the
fundamentals was pilifuUy small.

When crude oil was first used under
steam boilers the ordinary coal grates
were partially covered with a course of
firebrick and the burners were inserted
through holes chipped in the fire doors.
Practically no departure from this ar-
rangement is made even today when oil
fuel has been in use for years.

Dozens of similar examples could be
offered.

This lack of willingness to take the
initiative, to break away from the beaten
path, retards the progress of the world
perhaps more than anyone has ever
remotely suspected. And, after all. is
it not due mostly to man's inability or
unwillingness to reason for himself? Do
not the most of us, either by preference
or necessity, "let George do it"?

Oil Fuel

In spite of many advantages, such as
ease of handling, cleanliness and flex-
ibility of operation, the adoption of oil
fuel, except in localities where coal is
expensive and oil relatively cheap, is
progressing very slowly. This is largely
due to its general inability to compete in
price with the lower grades of coal which
are now being burned successfully, and
to the relatively limited supply.

Regarding the latter point, however,
since the discovery of the Texas and
California oilfields a few years ago the
output has been greatly increased. Last
year the totaJ production of crude petro-
leum in the United States was two hun-
dred and sixteen million barrels, much
of this, however, being used for in-
dustrial purposes. During the same per-
iod four hundred and eighty million tons
of coal were mined in this country. Con-
sidering, on an average, that one ton of
coal is equivalent to four barrels of oil,
it will be seen that the present produc-
tion of oil (including that used for in-
dustrial purposes) would have to be
increased ninefold in order to supplant
coal as fuel.

Reference to the figures of the tests
with oil fuel (see page 170 of the pres-
ent issue) which were conducted by the
Babcock & Wilcox Company for the

Navy Department will show some in-
teresting results. The efficiencies at-
tained were not as high as those reached
in the tests at the Redondo plant a few-
years ago, but in the present case the
rate of forcing was much higher.

In test No. 1 the heretofore unheard
of evaporation of 15.83 pounds of water
per square foot of heating surface was
attained. To produce this 13.69 pounds
of oil per cubic foot of furnace volume,
equivalent to 75.34 pounds of coal per
square foot of grate surface per hour,
were burned. As might be expected,
the flue temperature was unusually high
in this case. In spite of this high rate
of forcing, the efficiency was not ma-
terially decreased, which speaks well
for the circulation in the boiler.

In viewing the results of these tests,
however, it must be remembered that
they were made with a closed fire room,
with steam jets in the stack, and were
conducted by men long experienced in
handling oil fuel — a combination of con-
ditions which would not be met with in
ordinary operation, except perhaps in
some phases of naval practice. Hence
these results, while showing the pos-
sibilities of oil fuel, are not typical of
average everyday practice.

In speaking of the cause of a recent
boiler explosion an ex-inspector said to
a reporter. "The crack was on the in-
side of the outside sheet, and the boiler
was so small that a man could not get
inside in such a position as to see this
crack, even if he were to make an in-
vestigation.

"This crack was obscured from sight
by an inside lap, and the crack would
become deeper and deeper, caused by
the vibration. This was sufficient to
weaken the boiler and cause it to ex-
plode."

It is, of course, needless to say that
the exploded boiler was of the lap-seam
type and that the size of the boiler had
nothing to do with the invisibility of a
crack which could be discovered only by
unmaking the boiler and opening the
seam until inspection was possible.

In deliberating whether to continue
the use of the isolated plant or to adopt
central-station service, the engineer's
earnings outside of his regular duties
are usually overlooked. In many plants
the engineer is the plumber, the steam-
fitter, the carpenter and the machinist,
and when he is eliminated the odd jobs
that fell to him will have to be paid for
at the regular rates plus the shop owner's.

.According to the United States Geo-
logical Survey, nearly 100.000 horse-
power is being developed from falling
water in Tennessee. The completion of
water-power projects now under con-
struction will probably more than double
the present development in that State.

August hr 1911

POWER

189

"F^l? /C?!

-C«

i"^r=%

i^^^^^

M.

Opening Gage Glass J'ahves
After putting in a new water glass,
which valve should be opened first?

O. G. G.
When a new water gage has been put
in, open the drip cock at the bottom
of the column and open the top cock,
admitting steam to the glass slowly and
allowing it to heat up before the water
connection is open. The glass will in
this way be heated more evenly and, if it
breaks, the results will be less disastrous
than if the water cock were opened first.

Gain /row Use of Condenser

Is there any saving in using a con-
denser, when there is use for the steam
elsewhere? What is the gain in using a
condenser ordinarily?

H. G. Y.

There is no economy in employing a
condenser and sending heat units into
the river when they are useful for heat-
ing or manufacturing purposes. A steam
engine used as a reducing valve be-
tween a high- and low-pressure system
is the most economical heat engine in ex-
istence.

The gain in using a condenser de-

Questjons ar^

not answered unless

accompanied by the^

name and address of the

inquirer. This page is

for you when stuck-

use it

"Steam Power Plant Engineering" gives
the effects produced in some average
cases.

Hight and Pressure of Hater

The pressure at the bottom of a stand-
pipe is 95 pounds per square inch; what
is the hight of the water?

H. P. W.

A column of water 1 foot in hight at
rest will press upon its base with a
pressure of 0.433 pound per square inch.

Direction of Compressor Rotation

Is there any particular reason why an
air compressor should run under?

D. C. R.

There is none. In fact, the friction
will be slightly less when runnin" ->ver.

EXAMPLE* OP TnE EFFECT OF COXDEXSING OX THE ECONOMY
I.VC, ENGINES

RECIPROCAT-

lNt'RE.\SE

Die to

Nu

NCONDENSINC.

Ci.xo

^N>iN.;

CoN*DtN'S>IXG

Back

Pre.-i-

Steam

sure.

Con-

.Steam

Pounds

sump-

Consump-

per

tion.

Refer-

tion,

Square

Pounds

ence

Initial

Horse-

Pounds

Initial

Inch

Horse-

^%..

In

In Econ-

Num-

Gaee

power

I)er H.P.-

Gaee

Ah.so-

power

Power,

omy.

ber

Prwwurc

Developed

Hour

Prexsure

lute

Developed

Hour

Percent.

Percent.

1

147

.54.7

19 2

149

1.6

83.4

14.8

.52,5

25

2

148

.MO

19 3

147

4

16.9

12. .5

Z

126

83

23 8

1.30

7 4

116

19.1

3» 8

19 7

4

67.6

209

28.9

67

4 .i

213

22

1.9

23.5

h

103.8

177 5

22.1

103 8

1.2

l.W

16.5

25 . 1

6

114

160

31

114

168

27

2

12.9

7

96

120

23.9

96

4

14.T

19.4

20.8

8

118

267

23.24

119

4 2

276.9

16

3.7

31

9

7.5.9

310

2.5 6

79

6 4

336

20.5

8 7

19 9

10

62. 5

451

.30 1

63 6

7 8

444

23

23 fi

11

186 7

40 4

18.7

184 6

18

29.8

12.7

32

pends upon the initial pressure and the
ratio of expansion, as well as upon the
type of engine. With a very low initial
pressure and an early cutoff the area of
the diagram below the atmospheric line
will be a large proportion of the whole,
while with a high initial pressure and
a late cutoff the vacuum area will be
a much smaller percentage. The effect
of the condenser in carrying the engine
toward or away from its maximum effi-
ciency should be considered. The ac-
companying table from Gebhardt's

Fjqua/iz,er

What is an equalizer as used on a
boiler having three lugs on a side and
how is it constructed?

H. E. C.

An equalizer is a device which equal-
izes the distribution of the weight on the
three brackets on each side of a boiler.
The front ones are usually attached to an
overhead girder and the others to a short
beam which is suspended at the middle
from another girder.

Length of Rivet
How can I tell what length to have
rivets so they will fill the rivet holes
and form a head equal in strength to the
body of rivet? What is the formula for
finding the strength of rivet heads?

E. C. H.
The rules depend on the style of head
and do not give tTie exact sizes. For
common conical heads the rivet should
project through the sheet 1^ diameters
for hand riveting and Yn to 14 inch more
for machine work.

Chamfered Rivet Holes
Why are rivet holes chamfered before
driving the rivets?

H. D. P.
They are chamfered for the purpose
of removing the bur left by the drill or
reamer.

Horsepoiver for Given Cutoff

In a simple noncondensing I2x26-inch
engine, cutoff occurs at 5,s of the stroke.
With 100 revolutions per minute and 90
pounds steam pressure, what is the ap-
proximate horsepower?

H. G. C.
The mean pressure of expanding steam
at s^ cutoff is 91.87 per cent, of the
initial. Assuming that 90 pounds gage
pressure is realized in the cylinder and
that the steam is exhausted at 2 pounds
pressure above the atmosphere, the mean
forw'ard pressure on the piston will be

105 X 0.9187 = 96.46 pounds
The mean effective pressure is the mean
pressure less the back pressure which
in this case is taken at 16.7 pounds ab-
solute.

96.46 — 16.7 = 79.77 pounds
The horsepower of an engine is ex-
pressed by the formula

„ ^ PAS

.13,000

in which

P — Mean effective pressure;
A = Area of piston;
S = Speed of piston in feet per min-
ute.
Then
70.77 X it.i X 4.15.

33,000

The actual horsepower developed
would, owing to the failure to realize
full pressures in the cylinder up to the
point of cutoff, wire drawing, etc., prob-
ably be about 85 per cent, of the theo-
retical, or

118.82 y 0.85 = 100.9P horsepower

118.82 horsepoiver

190

POWER

August 1. 1911

Heating and Ventilation

Combined Vacuum and
Gravit}' Return Heat-
ing System
By Charles A. Fuller

A ver>' interesting combination of vac^
uum exhaust-steam and gravity-return
heating system is found in the New York
Trade School, at Sixty-seventh street
and First avenue, New York City. The
main part of the buildings, including
shops, workrooms, classrooms, etc., was
originally heated with exhaust steam
from the power plant on a gravity-re-
turn system. To get proper circulation,
however, it was necessary to carry quite
an excessive back pressure on the en-
gine, due to the length of lines and small
size of piping. The office building was
heated by a separate plant, using a low-
pressure boiler and gravity-return sys-
tem. No attempt had been made to op-
erate the two systems in conjunction.

Fig. 1. Weighted Check Valve

The reason for making alterations was
to cut down the excessive back pres-
sure on the engine by the use of a vac-
uum system, and to connect the two
systems so that when exhaust steam was
available the entire plant, including the
office building, could be heated by this
means. It was also necessary to arrange
the office plant to operate independently

as a gravity-return system at such times
when exhaust steam could not be had
for heating purposes.

The so called vacuum-heating system
produces circulation of steam by remov-
ing the air and condensation from the
coils and radiators with a vacuum pump
or other vacuum-producing device. Creat-
ing the desired vacuum in the return
lines and removing the air from thje sys-
tem allow the exhaust steam from the
engine to flow into the heating system
at approximately atmospheric pressure.
The annoyance of air valves on coils and
radiators is also done away with, the
air being taken out from the return lines
by the pumps.

Small automatic traps of the float,
thermostatic or weighted check-valve de-
sign, are placed on the return ends of
each radiator or coil, which allow the
air and condensation to pass but prevent
or regulate the passage of steam into
the return lines.

In this particular plant weighted check
valves were installed in the branch re-
turns in the basement at the points where
these returns discharged into the main
return line. The return end of each
radiator and coil was equipped with a
swing check valve having a restricted
orifice. The weighted check valves shoyn
in the illustration are provided with
means for adjustment by adding or re-
moving weights as may be required.
These valves then serve to divide the
whole plant into small groups.

The drop in pressure in the supply
mains and drop in vacuum in the return
mains to any particular group may be
compensated for by removing the weights
in the valve controlling that particular
group; they are removed until the re-
quired amount of vacuum to produce
proper circulation is obtained. Means are
also provided for balancing the swing
check valves, thus compensating for any
drop in pressure within the group itself.
This drop, however, is usually so slight
that this precaution is not necessarv'. The
adjustment of the weighted check valves

produces practically the same difference
in pressure between the supply and re-
turn end of each radiator or coil in the
entire plant, regardless of its distance
from the source of supply.

In the accompanying plan, Fig. 3,
the basements of the various buildings
are shown. The general arrangement of
the supply and return mains is indicated
on this plan with the location of the
weighted check valves shown in the
branch returns. In the office and library

Fig. 2. Swing Check Valve

building is shown the low-pressure
boiler used for heating this building
when the power plant is not running. A
plan and elevation showing the general
arrangement of piping is given in Fig.
4, which is drawn to a larger scale.

The steam-supply main from the power
plant enters the basement at F and joins
the steam supply from the low-pressure
boiler at G. From here the main M
distributes through the various supply
risers to the radiators. The return end
of each radiator is equipped with the
swing check valve previously described.
These returns all connect into the re-
turn main O. .At the point R this return
branches into two lines, one running as
shown through the weighted check valve
and thence to the main return line run-
ning to the vacuum pump. The other
line from R drops below the water line
and enters the low-pressure boiler
through valve D in the usual manner.
The steam mains are all dripped into the
main drip line P which enters the main
return at the point K.

The air valves on all the radiators were
removed and the openings plugged. One
large thermostatic air valve is connected
into the main return above the point
where this return drops to the water line
of the boiler. This valve ser\'es to re-
move all the air when the low-pressure
boiler is in service. The discharge from

August 1, lyii

POWER

191

the air valve is equipped with a globe
valve which is closed when the building
is heated by the vacuum system from
the power plant. The drip main is con-
nected into the return main below the
water level so that no steam can short-
circuit through the drip points to the
return.

and into the main return of the larger
system. The condensation in the steam
mains passes as before into the drip line
P and back to the point K. Here it rises
into the return main at R. Because of
the weighted check valve in the branch
return there is a comparatively low dif-
ference in pressure between the steam

Fic. 3. Basements of Buildings

To operate the plant frsm the low-
pressure boiler as a gravity return, valves
B and C are closed, valves A and D are
opened and also the small valve £ on the
discharge from the air valve. The sys-
tem, then being entirely separated from
the main steam and return line, can be
operated independently and also inter-
feres in no way with the operation of the
main system.

To cut out the boiler and heat the
building by the vacuum system, valves
A and D arc closed and the valve fe" on
the air line is closed to prevent the air
from entering into the return mains.
Valves B and C are opened. Steam then
enters the line F and is distributed in the
same manner as before. The air and
condensation pass through the return
main N through the weighted check valve

sible to make any alterations in it. or
to run a supplementary branch return
line to handle the condensation from
this portion of the building.

It was therefore possible to install only
one weighted check valve in this return
line at the point T as shown on the plan.
This made an extremely large group to
be controlled by one weighted check
valve, and it was necessary to divide the
group by means of introducing what is
knowti as the Paul svstem, on one por-
tion of the group. At the point S the
return line was loop sealed as shown
in the sketch. This established an in-
dependent water line in the return main
and separated the group R — S from the
group S — T. At a point in the branch
return above the water line in the loop
seal, a large thermostatic air valve was
placed and an air line was run from this
valve and connected into the high-vacuum
compartment of the main return line. (By
high-vacuum compartment is meant the
part of the return main between the
weighted check valve and the vacuum
pump.)

It can readily be seen that the air
from this portion of the system would
then be taken out through the air line
and back to the pump through a sep-
arate circuit, while the water of con-
densation would pass through the loop

and return pipes which is not sufficient to
lift the water out of this seal and cause
short-circuiting through the drip line.

It can readily be seen that, as the vac-
uum-return line is connected at the water
line of the boiler, with valves D and A
closed the water level in the boiler can
in no way be affected by the action of
the vacuum pump, and it is not necessary
to adiust this each time the boiler is put
into service.

Another interesting feature in connec-
tion with this plant will be found in the
return line designated by the letters /?,
•S and T, Fig. .3. This return line handles
the condensation from practically one-
half of the entire plant. From the point
S back to the power plant this return was
laid below the floor and it was impos-

Elevotion

Fig. 4. General Layout of Piping

seal back through the return line S — T
through the weighted check valve and to
the pump. The air valve works thermo-
statically and will close as soon as steam
attempts to pass, and, at the same time,
when any air collects in the system this
valve will open and allow this air to
escape into the main return line.

192

POWER

August 1, 1911

Legislation on Compulsory
Ventilation*

The last report received from New
York shows the factory-ventilation bill
still in the balance. This bill is an
amendment to the one passed in 1909
and is a credit to the committee of which
D. D. Kimball is chairman. It is hoped
that the bill will pass, although there
has been some agitation toward the
formation of a commission to investigate
the entire factory proposition and re-
port back a general bill covering all
phases of the factory work. Other than
this there seems to be no serious op-
position to the bill.

In reading over the present statute and
comparing it with the proposed amend-
ment one is impressed with the improve-
ment. The amendment is very definite
concerning the quality of the air, where-
as the present law is very vague and
leaves the matter open to the discretion
of the commissioner of labor. Two
bases are given for determining the
quality of the air, as shown by this
quotation from the proposed law:

"A workroom shall be deemed to be
provided with sufficient means of ventila-
tion if provided with means of ventilation
which will supply constantly in all parts
of the room air, either of the quality
or in the quantity hereinafter prescribed.
A workroom shall be deemed to be prop-
erly and sufficiently ventilated if the
air in the working parts thereof does not
contain more than nine parts of carbon
dioxide in 10,000 volumes of air in ex-
cess of the number of parts of carbon
dioxide in 10,000 volumes of the ex-
terior air, or if there is constantly sup-
plied throughout the interior of the room
at least 1200 cubic feet of air per hour
for each person therein present and em-
ployed, and in addition thereto at least
1000 cubic feet of air per hour for each
cubic foot of gas burned per hour, such
air to be taken from an uncontaminated
source; provided, however, that if gases,
fumes, vapors, fibers, dust or other im-
purities are generated or released in the
course of the business carried on there-
in, the room must be further ventilated
by providing at the point of origin of
such impurities proper hoods and pipes
by and through which such impurities
shall be collected and removed, and such
pipes and hoods shall be connected to
exhaust fans of sufficient capacity and
power to remove such impurities and
such fans shall be kept running con-
stantly while such impurities are being
generated or released."

The question of temperature, which
was not mentioned in the present law,
is also taken up as follows: "And pro-
vided further, that the temperature in

*.\l).stract of report of committee on Com-
pulsoiy Ventilation to American Society of
Ilealins and Ventilating Engineers, Chicago.
June 6 to 8.

any factory workroom, except a boiler
room, shall not exceed 72 degrees Fah-
renheit, as determined by the wet-bulb
thermometer, unless the temperature of
the exterior air exceeds 70 degrees Fah-
renheit, ?s determined by the same pro-
cess, in which case the wet-bulb tem-
perature of the workroom shall not ex-
ceed that of the exterior air by more
than 5 degrees."

In Massachusetts the committee on
compulsory ventilation is having its ups
and downs also. Since the last meeting
a commission appointed by the governor
to investigate the subject presented a
bill to the legislature which would pro-
vide for an unpaid commission of five
members whose duty it would be to ap-
point a chief commissioner, two deputies,
a register and 50 inspectors; 10 of these
inspectors are to be women. The un-
paid commissioners would have power to
fix the term of office, adjust the salaries
and discharge and appoint employees.
This bill had a large opposition. At last
report this bill has been called up for
final vote.

The work of the Illinois committee,
since the last meeting, has been done in
connection with Doctor Evans and the
Chicago department of health. A great
amount of work has been accomplished
but there is still a great deal to do.

Indiana fell into line on March 3 with
a ventilation law that is good as a
starter. The State committee, with Mr.
Weinshank as chairman, working in con-
nection with the Medical Association and
Doctor Hurty, the State health officer,
succeeded in passing a bill affecting prin-
cipally the schools of the State. Extracts
regarding the heating and the ventilating
are as follows:

"The ground floor of all school houses
shall be raised at least 3 feet above the
ground level, and have, when possible,
dry, well lighted basements under the
entire building, and shall have a solid
foundation of brick, tile, stone or con-
crete, and the area between the ground
and the floor shall be thoroughly venti-
lated. Each pupil shall be provided with
not less than 225 cubic feet of space.

"Cloakrooms, well lighted, warmed and
ventilated, or sanitary lockers shall be
provided for each study schoolroom.

"Ventilating heating stoves, furnaces
and heaters of all kinds, shall be capable
of maintaining a temperature of 70 de-
grees Fahrenheit in zero weather and of
maintaining a relative humidity of at
least 40 per cent.; and said heaters of all
kinds shall take air from outside the
building, and after heating introduce it
into the schoolroom at a point not less
than 5 nor more than 7 feet from the
floor, at a minimum rate of 30 cubic
feet per minute per pupil, regardless of
outside atmospheric conditions; provided,
that when direct-indirect steam heating
is adopted, this provision as to hight of
entrance of hot air shall not apply. Halls,

office rooms, laboratories and manual-
training rooms may have direct-steam
radiators, but direct-steam heating is for-
bidden for study schoolrooms, and direct-
indirect steam heating is permitted. All
schoolrooms shall be provided with venti-
lating ducts of ample size to withdraw
the air at least four times every hour,
and said ducts and their openings shall
be on the same side of the room with
the hot-air ducts.

"Whenever, for any cause, the tem-
perature of a schoolroom falls to 60 de-
grees Fahrenheit or below, without the
immediate prospect of the proper tem-
perature, namely, not less than 70 de-
grees Fahrenheit being attained, the
teacher shall dismiss the school until
the fault is corrected."

The committee is informed on good
authority that this year Nebraska had a
very satisfactory bill prepared for pre-
sentation, but it did not pass. Some of
the spirit of the law is to be found in
the following requirements which are
now a part of their State laws: In cities
of the metropolitan class (100,000 or
more population I and in cities of the first
class (40,000 to 100,000) mention is
made that "proper ventilation shall be
provided." The words "proper ventila-
tion" are not defined in any way, neither
is there any statement defining the per-
sons involved nor the penalty to be in-
flicted for nonfulfilment of requirement.
The laws are very satisfactory concern-
ing safety from fires, overcrowding, etc.,
but touch lightly upon pure air.

The health program recently proposed
by the Nebraska Association of School
Principals and Superintendents has a
good ring to it. It requests, as compul-
sory, ventilating heating plants, cleaning
and disinfecting of schoolhouses at least
twice each year, submission of all school-
house plans to a State architect for ap-
proval, medical inspection of school
children and medical inspection of all
school teachers.

In Wisconsin a factory-ventilation bill
was introduced this spring which reads
in part as follows: "In factories, mills,
workshops, mercantile or mechanical es-
tablishments, the windows shall be so ar-
ranged that they will permit the cir-
culation of fresh air from the outside
of the building at all times and shall be
so constructed as to prevent direct drafts
from striking the employees working
within. Where the circulation of fresh
air cannot satisfactorily be secured
through an arrangement of the windows,
any system of ventilation that will keep
the air therein free from substances and
qualities injurious to the health or com-
fort of the employees, either by fans,
suction devices and the like, which shall
be approved by the bureau of labor and
industrial statistics, may be installed.

"Every factory inspector and every as-
sistant factory inspector charged with
the inspection of factories, mills, work-

August 1, 1911

POWER

193

shops, mercantile or mechanical estab-
lishments, shall investigate the system
of ventilation in every plant inspected,
and wherever same is not found to com-
ply with the provisions of this act, notice
thereof shall be given to the owner or
owners thereof, or to the officer or of-
ficers, if said factories, mills, workshops,
mercantile or mechanical establishments
be corporations."

Kansas recently passed a compulsory
ventilation law for theaters, picture
shows, churches and other public build-
ings, of which the following is an ab-
stract: "Section 4. It shall be unlawful
for the owner, proprietors or lessee to
operate any theater, picture show or
place of amusement in any structure,
room or place in the State of Kansas
which structure, room or place is capable
of containing 50 or more persons unless
the system of ventilation is capable of
supplying at least 30 cubic feet of fresh
air per minute per person therein.

"Section 5. All structures, rooms or
places used for the purpose mentioned in
section 4 of this act having less than
500 cubic feet of air space for each per-
son, and all rooms having less than
2000 cubic feet of air space for each
person in which the outside-window and
door area used for ventilation is less than
one-eighth of the floor area, shall be
provided with a draft fan or other arti-
ficial means of ventilation installed so as
to force the stagnant air outward from
said structure, room or place. In the
end of the room opposite said fan an
inlet ventilator shall be provided of suffi-
cient size to admit the required amount
of fresh air as provided in section 4 of
this act. Inspection is to be made at
least once every six months, and failure
to comply with the law makes the pro-
prietor, lessee or manager subject to a
fine of -SIO per day for such failure."

On March 6, North Dakota adopted a
compulsory-ventilation law applying prin-
cipally to schools and assembly rooms.
The following are extracts:

"Section I. No building which is de-
signed to be used in whole or in part
as a public-school building shall be
erected until a copy of the plans thereof
has been submitted to the State superin-
tendent of public instruction who for the
purposes of carrying out the provisions
of this act is hereby designated as in-
spector of said public-school building
plans and specifications, by the person
causing its erection by the architect
thereof; such plans shall include the
method of ventilation provided thereof,
and a copy of the specifications therefor.
"Section 2. Such plans and specifica-
tions shall show in detail the ventilation,
heating and lighting of such building.
The State superintendent of public in-
struction shall not approve any plans for
the erection of any school building or ad-
dition thereto unless the same shall pro-

vide at least 12 square feet of floor space
and 200 cubic feet of air space for each
pupil to be accommodated in each study
or recitation room therein. All ceilings
shall be approved by him unless pro-
vision is made therein for assuring at
least 30 cubic feet of pure air every min-
ute per pupil and wanned to maintain
an average temperature of 70 degrees
Fahrenheit during the coldest weather,
and the facilities for exhausting the foul
or vitiated air therein shall be positive
and independent of atmospheric changes.
"Section 5. No wooden flue or air
duct for heating or ventilating purposes
shall be placed in any building which is
subject to the provision of this act, and
no pipe for conveying hot air or steam
in such building shall be placed or re-
main within 1 inch of any woodwork,
unless protected by suitable guards or
casings of incombustible material."

Westinghouse Automatic
Bleeder Turbine

The accompanying engraving shows in
section a modification of the ^X'esting-
house turbine which was exhibited to
the members of the National District
Heating Association at the time of their
recent visit to the Westinghouse works.
The turbine is adapted to be bled at one
of the intermediate stages, steam being
taken from it as is often done from the
receiver of a compound engine for heat-
ing or industrial purposes.

filled chamber is provided to dampen the
movements due to sudden fluctuations in
pressure. If the pressure in the chamber
/ should fall, whether by reason of a
greater demand for steam for heating
or a lessened supply through the tur-
bine, the valve D will move toward its
seat, allowing less steam to go through
the lower stage of the turbine. Con-
versely, if the pressure in / rises, the
valve will open wider and relieve the
pressure by allowing more steam to go
through the low-pressure end to the con-
denser.

In the production of coal Colorado
ranked first among the States west of
the Mississippi and seventh among all
the coal-producing States during 1910.
Colorado's increase in tonnage was the
largest and was more than one-third of
the total increase made in the seven
States comprising the Rocky Mountain
and Great Plains provinces. In the Mis-
sissippi Valley States the production in
1910 was materially cut down by the
miners' strike. The cessation of opera-
tions among the miners in the Southwest-
ern States created an unusual demand
upon the mines of Colorado, New Mexico
and Wyoming, the demand coming prin-
cipally from the railroads running be-
tween the Rocky mountains and the Mis-
sissippi. There was also a better demand
for domestic fuel and considerable quan-
tities of coal for winter use were stored
in the cellars of householders.

The miners' strike caused an increase

Westinghouse Bleeder Turbine

A partition is provided at A, packed at
the shaft with the labyrinth packing S;
a connection is made at C to the heat-
ing system and that steam which is not
drawn ofT for its demands passes through
the passage controlled by the valve D
to the low-pressure end of the turbine
and the condenser.

The valve D is controlled by the pres-
sure in the chamber / and may be set
by dead weighting it at H to maintain
any desired pressure in the heating sys-
tem. The piston E inclosed in an oil-

in Colorado's coal production of 11.73
per cent., from 10.7lti,936 short tons
in 1909 to 11,973,736 tons in 1910. The
value increased from 514,296,012 to S17,-
026,934, a gain of 19.1 per cent. The
average price per ton advanced from
S1..13 in 1000 (o '^1.42 in 1910.

Low-priced men arc high-priced lux-
uries in all departments of all industries,
but in no class of work is this needless
indulgence so costly in dollars ano cents
as it is in the power plant.

Stationary Engineers Frolic

The local National Association of Sta-
tionary Engineers, of Portland, Ore.,
held its third annual "frolic" at Golden
Gate park, Sunday, July 16. The steamer
"Joseph Kellogg" conveyed the members,
their families, and friends to the
grounds.

The program was one devoted to sport,
ranging from contests of skill, with
prizes offered to stimulate interest, to a
ball game between the engineers and the
cigarmakcrs of the city. An orchestra
contributed to the enjoyment.

The committee of arrangements was
comprised of the following members:
Frank Akers, William Etchell, John
Faulkner, F. W. Kroll, James Maguire,
William Mackenzie, W. H. Murphy and
C. Nam.

A large attendance made the outing
a great success.

Disastrous Turbine Explosion

At the time of going to press it is re-
ported that a 5000-kilowatt Curtis tur-
bine at the Riverton station of the Il-
linois Traction Company has exploded,
resulting in the deaths of two men and
severe injuries to two others. A more
detailed account of the accident will ap-
pear in our next issue.

POWER

of which firm he became a partner. He
severed his connection with that firm in
1887 to take the presidency of the South-
wark Foundry and Machine Company,
and held that office until the time of his
death.

PERSONAL

Osborn Monnett, late Western editor
of Power, with headquarters at Chicago,
has been appointed smoke inspector for
the city of Chicago.

Joseph H. McNeill, late chief inspector
of boilers for Massachusetts, has been
made a duputy commissioner, with in-
creased authority and remuneration.

Raoul Beauvais, the five-year old son
of Alfred Beauvais, an engineer of Cen-
tral Falls, R. I., disappeared oh June
7, and is thought to have been kidnapped
by a band of gypsies. The boy is 3
feet 6 inches tall and of dark complex-
ion, having black hair and dark brown
eyes. The mayor of Central Falls has
offered a reward of $100 for information
that will lead to his return and the ap-
prehension of the kidnappers.

OBITUARY

James C. Brooks, president of the
Southwark Foundry and Machine Com-
pany, died on the morning of July
KS in the Pennsylvania hospital. He
was stricken with acute heart trouble and,
while he rallied, the improvement was
only temporary.

Mr. Brooks served throughout the Civil
War and attained the rank of major. At
the close of the war he entered mercan-
tile life, but after some years became
associated with William Sellers & Co.,

George Farrington Hughson, president
of the Hughson Steam Specialty Com-
pany, of Chicago, died Wednesday morn-
ing, July 19, at his residence, 51 16 Wood-
lawn avenue. Mr. Hughson was born
March 25, 1860, at St. Paul, Minn., and
was 51 years old at the time of his death.

He had lived in Chicago for twenty-
three years and during that time was
prominently identified with the steam-
specialty business, being for a number
of years vice-president and general sales
manager of the John Davis Company.
About two years ago, on the retirement
of the latter company from the steam-
specialty field, he took over the line of
goods handled by this firm and formed
the Hughson Steam Specialty Company.
He was a member of the Illinois Athletic
Club, South Shore Country Club, Glen
Oak Country Club and the Western
Trades Gulf Association.

A widow and one son, Harry H.
Hughson. survive him.

NEW PUBLICATIONS

CONTINUOUS-CURRE.NT MACHINE DESIGN.

By William Cramp. Published by
D. Van Nostrand Company, New
York, 1910. Cloth; 260 pages, 5/,
x8;.. inches; 137 illustrations; many
tables. Price, $2.50.
This is one of the most practical text-
books that has ever come to the review-
er's desk. The author is an experienced
designer as well as a college lecturer,
and the combined practices eminently
equipped him for producing the present
work.

To get the least attractive part of the
task done first, on the same principle
that incites the small boy to save his
best apple until the last, the reviewer
calls attention to the following more
important defects:

On page 15, the statement that mag-
netic densities at polefaces and teeth
roots "cannot change much" from the
values 54,000 and 146,000, respectively,
is, to an experienced designer, obviously
unwarranted.

The vertical scale of Fig. 5 gives one-
tenth of the correct values, which should
therefore be 10, 20, 30, etc., where the
figures now read 1, 2, 3, etc.

The reference to Fig. 10 in the fif-
teenth line on page 6 should be to Fig. 7.
The factor Rci\ per min. should be
included in the numerator of the right-
hand member of the equation for watts,
five lines from the bottom of page 21 ;

the fraction - in Table 1 on the same

.August 1, 1911

30,000 for flux density in a cast-iron
yoke is below good practice and incon-
sistent with the value adopted on page 18.

The assumption on page 22 that the
product pole diameter or width X num-
ber of poles is 1 'A times the product
polar bore diameter y leakage coefficient
is too empirical as a hard-and-fast work-
ing rule, which the author makes of it
all through the book. It is good enough
as a ratio to be striven for, but using
it as a definite basis for all fundamental
calculations (pages 84. 86, 128, 131. 184,
200, etc. ) is a rather arbitrary pro-
cedure, likely to entail extensive correc-
tions and readjustments of the pre-
liminary values thereby derived.

In Fig. 52, page 93, conductor No. 14
should be marked 11' instead of VI' and
No. 16 should be marked III' instead of
III.

On page 96 the wording of the fourth
line from the bottom should be "Then
the resistance of each armature path
of," instead of "Then resistance of arma-
ture circuit of," because the author

means the resistance of - of the wire

f
in the winding, p being the number of
field magnet poles.

On page 107, about ten lines from, the
top, the author says that those con-
ductors in a two-path armature winding
which lie between two brushes of the
same polarity are inactive; if this were
true, the entire winding would be in-
active. What he evidently means is that
the coil which directly connects two
equipotential neutral points on the com-
mutator is inactive. Near the bottom of
the same page it is stated that a two-
path winding must have an even num-
ber of conductors; the inference would
naturally be that a multipath winding
can have either an even or an odd num-
ber of conductors, which, of course, is
untrue.

On page 127 in the first equation the
sign "^" should be used instead of "\"
in the numerator.

On page 162, the left-hand member
of the second equation should be "sin.
a" instead of "cos, a." Moreover, the
formula for deriving the value of Le
would be less tedious to handle if it
were reduced and transposed to read:
(^
Lc =

instead of the way the author states it.

On page 177, in the thirteenth and j|i
twelfth lines from the bottom, the author
says a machine will have its core length
"increased in almost inverse proportion
for lower or higher speeds," While this
is true algebraically, it is not true phys-
ically; it would be much clearer to a
student if he said "increased or de-
creased," etc.

On page 230 in Appendix IV the state-
ment that equation (1) for the potential

August 1. 1911

P O \(' E R

195

drop at the terminals of a coil is that
"for a given field current" is unneces-
sarily limited; the equation is true for
any field current whatever. The final
equation for coil dimensions, on the
same page, would be somewhat more
logically expressed if the factor dc were
placed in the denominator of the right-
hand member, since the mean length
of turn cannot be known without know-
ing the value of dc ; the derivation of
the formula, moreover, is not particular-
ly explicit.

Besides the foregoing specific com-
ments, it may be pointed out that the au-
thor's use of the nonstandard abbrevia-
tion "G. C. F." is unfortunate and tends
to obscure; the method of procedure ex-
emplified on page 183 and those follow-
ing is not well chosen as to sequence and
rather arbitrary as to interrelations; the
illustrations reproduced from drawings
are uniformly poor.

Having got through with the disagree-
able comments, it gives the reviewer
pleasure to say that the book is far and
away the best one on the subject that
has been published within recent years
and the only one embodying individuality
of treatment or presenting any really
original material that has appeared since
Parshall & Hobart's "Electric Gen-
erators." The chapter on the tempera-
ture rise of field magnet coils is espe-
cially good, the subject being discussed
intelligently, with a view to actual con-
ditions, instead of academically, with
respect to the one set of conditions
which never exists. The author is mis-
taken, however, in thinking that his
method of taking into account simultane-
ously the ampere-turns, watts lost, tem-
perature rise and coil dimensions is en-
tirely new. The same general method
was described in the American Electrician
almost exactly ten years ago and elabo-
rate tables were presented to facilitate
the adjustment of these interdependent
values.

The discussion of temperature rise in
armatures and commutators is also par-
ticularly sensible and the chapters on
insulation and mechanical construction
are examples of highly judicious selec-
tion and clear presentation of those data
which are of the most practical use-
fulness.

The ireatment of topics which neces-
sitate mathematics is, for the most part,
as simple and direct as the nature of the
case will allow; the few exceptions have
been noted.

All in all, the author's work is highly
praiseworthy.

The authors have translated the work
of Fritz Neumann on "Die Zentrifugal-
pumpen" and have adopted both the
theory expounded therein and the method
of calculating impellers, which is totally
unsuited to the present needs of the
pump designer. Thus on page 126, ex-
ample 1 deals with the problem: "An
impeller and guide vanes are to be de-
signed for a multistage high-pressure
centrifugal pump to meet the following
conditions: Head = 65 feet; quantity =
70 cubic feet per minute."

They proceed to assume the outer
impeller diameter to be 12 inches, the
outer impeller angle to be 155 degrees
and the number of blades to be 10.
Introducing these values in typical equa-
tions evolved in the first part of the book,
they find the peripheral velocity, which,
combined with the impeller diameter and
the usual constants, gives the initial num-
ber of revolutions per minute as 1565.

They find that the impeller belongs to
a certain class which becomes char-
acterized by certain coefficients A and B
such that the number of revolutions for
any quantity and head of water can be
found from the equation

Centrifugal Kump?, tiieir Design and
Construction. By Louis C. Loewen-
sfein and Clarence P. Crissey. Pub-
lished by D. Van Nosirand Company.
New York. 1911. Cloth; 435 pages.
6x9 inches; 317 illustrations. Price,
S4.50 net.

»= — 11^.4-1-1 l\fA- + r,gH„B

The speed thus determined may be,
except by chance, totally out of reach
of the prime mover at hand, in which
case the whole guessing process has to
be done over.

Nowadays the pump manufacturer has
a stock of standard pump-casing pat-
terns, each capable of accommodating
a limited series of pump diameters, and
for each proposition it is almost invari-
ably expected when estimating that a
special impeller is to be made. There-
fore the characteristics and design of
that impeller must be produced promptly
and correctly to suit the conditions im-
posed by the customer. Eventually the
manufacturer accumulates a stock of im-
peller patterns whose characteristics have
been well tested and which are classified.

The authors believe strongly in the
efficiency of guide vanes surrounding the
periphery of the impeller; they say: "The
object of the guide vanes is to reduce
gradually, with minimum shock losses,
the absolute exit velocity H' a and thus
transform as much as possible of the

velocity head (— — \ into pressure." Here

is an unfortunate confusion which is
found throughout the book; head is pres-
sure, and a guide vane is a plate curved
to suit the design and intended to de-
flect the course of a stream. What is
meant is that guide passages, commonly
known to nil pump designers as dilTuser
passages, arc so shaped as to render
possible a gradual reduction of the veloc-
ity of the water issuing from the im-
peller, with the object of safeguarding
againstshocks and eddies transforming the
kinetic cncrgv into potential energy. They

appear not to realize that the water is-
sues from the impeller at a rate of from
40 to 100 feet per second, and that when
coming into contact with the walls of the
diffuser passages with such a high veloc-
ity important frictional losses are bound
to result, whereas, with a well propor-
tioned exit chamber, the water is put into
motion gradually, the rate being high
where contact occurs with the issuing
water, which spreads easily with the least
frictional loss, and very low against the
casing walls.

On page 83 is stated: "By exact and
very careful construcrion, pumps v ith-
out guide vanes can be n;ade to give
fairly satisfactory efficiencies." "The
construction of centrifugal pumps with-
out guide vanes is almost entirely con-
fined to low-pressui..' pumps, wliile this
construction can never find a place with
multistage high-pressure pumps." Yet
Fig. 267 shows a five-stage turbine-
driven pump delivering .500 gallons per
minute against the fairly high pressure
of 600 pounds per square ir.ch ( 1400 feet
head ) when running at 2900 revolutions
per minute. This pump has no diffu.^er
vanes nor passages, and at the official
tests showed an efficiency of 58 per cent.,
which is very high considering tne ex-
treme conditions imposed. With more
usual water conditions the efSciency of
this type of pump varies from 60 to S2
per cent.

In the text the shape of blades is con-
sidered dependent upon their number,
when theoretically the impeller is just
as efficient, barring frictional losses, with
only one as with 10 or 12 blades. For
high speed and relatively low head, and
with a steep characteristic curve one
blade may intercept, from inlet to out-
let, an angle of more than 180 degrees.
Then perhaps two blades are sufficient,
but that is not known at the start. At
any rate, it is usual and correct to de-
lineate the face of the blade first, then
determine its thickness, after which the
most suitable number of blades is se-
lected; finally the various cross-sectional
areas of the impeller passages or chan-
nels are calculated, and with these data
the diametral cross-section of the impeller
itself is delineated to conform to the
shape or style of pump case used.

It is well known that the shape of any
part of the blade has its importance and
that the action of the blade upon the
water must be continuous from the in-
let to the outlet; that is. in accordance
with the principles of the mechanics of
fluids. Therefore a correct design can-
not be produced, except by mere chance,
by making a stab at the two extreme
points and trusting to good looks for the
intermediate part.

While the theoretical part of the book
appears very weak, the remainder is ex-
ceedingly interesting and gives a very
good idea of the present stale nf the
an both in Europe and in this country.

POWER

August 1, 1911

BUSINESS ITEMS

The I'noljlo Snlnirhan Traction and IJght
Company. I'liPbio. Colo., b:is oideri-il. tliioub'li
II. M. Byllesby & Co.. of Chicaso. flora the
Westlnghoiise Electric and .ManHfactiirinj;
Company, three .'".OO-kva., oil-insiilated. water-
cooled, 44.000-volt transformers.

Some recent changes have been made In
the personnel of the Federal .Meliillic Tack-
ing Company, of Boston. Clinton \V. Tylee,
C. \V. Whcaton and Willard Staples have
hoiight the interest of K. C. Tarmenter. treas-
urer ot the company. Mr. Tylee succeeding
Mr. I'armenter as treasnrer, taking office
July 10.

The Rlchardson-Phenix Company has op-
ened a new engineering sales office in Thiia-
delphia, Penn., located in the Real Estate
Trust Ijullding. This office is under the man-
agement of .1. F. Mclndoo. who has had sev-
eral years' experience in general machinery
lubrication. Any questions pertaining to this
subject will be given prompt and careful at-
tention at this office.

The Parker Boiler Company, Philadelphia.
Penn., has recently received the following
orders : Victor-American Fuel Company, Gal-
lup, N. M., one 300-horsepower ; Smaltz-
Coodwin Company, Philadelphia, shoe manu-
facturer, two 177-horsepower : Pacific Cas
and Electric Company, Oakland. Cal.. four
77;ihorsepower, with Parker superheaters :
State Normal School, Valley City, N. D.. one
26;i-horsepower boiler.

The Peterson Engineering Company, lubri-
cation engineers, with offices in the Hudson
Terminal building, New York, and First Na-
tional Bank building, Chicago, announce that
it has taken over from the American Engin-
eering and Manufacturing Company, Inc.. of
Philadelphia. Penn.. the exclusive sale of the
Imperial elevator guide lubricator, manufac-
tured by the latter company. This device
will now be known as the Economy elevator
guide lubricator. Recent improvements in
this lubricator, it is claimed, enable it to
effect an economy of 10 to 15 per cent, in the
power consumption of elevators, due to the
thorough lubrication of the elevator guides,
causing a reduction in the fire hazard, in-
creasing the lifting capacity of the elevator,
reducing the oil or grease consumption from
200 to 300 per cent., and eliminating all
danger of life and limb, necessitated by the
old method of hand-swabbing elevator guides
from the top of the car. Interesting data
and publications on this elevator-guide lubri-
cator are now ready for distribution.

NEW EQUIPMENT

Northboro, Mass., will extend its water
system.

Edmonton, Alberta, will equiji a large new
pumping station.

Paul Ackerly, Vernon. Conn., will install
boiler and engine.

Hubbard, Ohio, will soon install a muni-
cipal water plant.

Oak Harbor, Ohio, will install a municipal
waterworks plant.

Port Stanley, Ont., will equip a new hy-
droelectric station.

Mliltown, B. C. will Install a new power
and heating plant.

WatsonvIIle. Cal.. is planning to install a
new waterworks system.

Hyde Park, Vt., will install water wheels
to develop 150 kilowatts.

Independence, Ore., has voted $25,000 bonds
for new waterworks system.

t^helsea, Vt., contemplates installing grav-
ity water system for fire protection.

The Old Colony Gas Company will build a
new gas plant at Weymouth, Mass.

I.. H. Grand.v, Mayesvilie. S. C, contem-
plates establishing a small ice plant.

Hyde Park, Vt., will install additional ma-
chinery in its electric-lighting plant.

U. Askins, Pratt and Illinois streets, In-
dianapolis, Ind., will install new boiler.

The Delaware & Hudson Railroad will erect
a large coal pocket at Schenectady, N. Y.

The Columbia Gas and Light Company, Cin-
cinnati, Ohio, will erect a large new plant.

Fire did ?18,000 damage at the plant of
the Babcock Ice Company. Evansvllle, Ind.

The Massachusetts Wharf Coal Company
will build a new coal pocket at Allston, Mass.

Armour & Co. will erect a $75,000 cold-
storage plant on Seventh street, San Diego,
Cal.

The capacity of the municipal lighting
plant at Lawrenceburg, Ind.. is to be in-
creased.

The Hlllsboro (Ohioi Light and Fuel Com-
pany is in the market for an absorption ice
machine.

The Enamel Brick and Concrete Company,
Salt Lake City, will erect a new boiler-plant
addition.

Medicine Hat, Alberta, will buy new
luimps, boilers, etc., for extensions to its
waterworks.

Newton, Iowa, will Install a 250-horse-
power water-tube boiler in the municipal
light plant.

The Sauk Rapids (Minn.) Water Power
Company will erect an electric-light an*
power plant.

Darling & Co., Center avenue and Forty-
Fifth street, Chicago, Hi., will build a new
boiler house.

A new power plant and laundry will be
built at the Good Samaritan Hospital, Cin-
cinnati, Ohio.

Sumas. Wash., will vote on issuance of
bonds for municipal electric-light, power and
heating plant.

Lindsay, Cal., has voted bonds for S55.000
for waterworks plant and $75,000 bonds for
sewer system.

Holyoke. Mass., will call for bids for in-
stalling a boiler house and steam plant at
the city farm.

The power and lighting plant on John Ar-
buckle's farm at New Paltz. N. Y., was de-
sti-oyed by tire.

The Edison Electric Company will build a
$35,000 substation at 3442-44 Calumet ave-
nue, Chicago, 111.

The Seattle (Wash.) Brewing and Malting
Company is having plans prepared for a new
cold-storage plant.

The Pavlak Mining Company, Jarbidge,
.Nev.. is planning to erect a 250-horsepower
hydroelectric plant.

The city of Cleveland, Ohio, has the con-
struction of a $2,000,000 electric-light plant
under consideration.

The Olean (N. Y.) Electric Light and Power
Company is preparing plans for a new power
plant at Ceres, N. Y.

The Lenox (Mass.) Water Company con-
templates Issuing $40,000 bonds for improv-
ing Its water system.

The Indiana & Michigan Electric Company,
South Bend. Ind.. will construct a power
house at Elkhart. Ind.

The power plant of the Mishawaka Woolen
Manufacturing Company, South Bend, Ind..
collapsed. Will be rebuilt.

The St. Louis (Mo.) Independent Packing
Company will erect a three-story addition to
its refrigerating building.

The State Board of Control. Olympia,
Wash., will erect a new power plant at the
Veteran.s' Home, Port Orchard.

The plant of the South Pittsburg (Penn.)
Electric Light and Power Company was de-
stroyed by fire. Will be rebuilt.

II. Delano, Corpus Chrlsti, Tex., Is plan-
ning the erection of an ice plant at Tucsen,
Ariz. Initial capacity, 50 tons daily.

The WinooskI River Power Company,
Waterbury, Vt., has awarded contract for the
construction of a dam and power bouse.

The Toronto Niagara Power Company will
l>uy ?.)00.000 worth of machinery for its
new power liouse at Niagara Falls, Ont.

Power-plant equipment will be required for
the 14-story building to be erected for the
Buffalo' f N. Y*. > General Electric Company.

Boston, Mass., is receiving bids Tor fur-
nishing a refrigeration plant using brine sys-
tem and a Corliss engine driven compressor.

The Washington Water Power Company,
Spokane, Wash., is planning to install a
lighting and power system at Spokane, Wash.

The State of Massachusetts has voted
?5000 for the purpose of installing new lx)il-
ers, etc., in the Stale prison at Charlestown,
Mass.

The B. & R. Rubber Company, North
Brookfield, Mass.. will install three boilers
and a tandem-compound engine for additional
power.

The Portland (Ore.) Railway. Light and
Power Company will make improvements to
its substation on First street to cost about
$10,000.

The San Francisco (Cal.) Gas and Electric
Company is having plans prepared for a new
power plant at Sacramento to cost about
$70,000.

The San .Joaquin Light and Power Com-
pany, Fresno, Cal.. is erecting a new substa-
tion at Clovis and will erect another at
Lemoore.

The Hamilton (Ohio) Ice Delivery Com-
pany has secured site for a new plant in
wliicb modern ice-making machinery will be
installed.

Power-plant equipment will be required for
the new hotel building to be erected by the
Dallas (Tex.) Hotel Association to cost about
$650,000.

The Thompson-Snow Amusement Company,
Los Angeles, Cal., will install an artificial
ice-skating rink and refrigerating plant at
Luna Park.

The Northern Idaho & Montesano Power
Company. Newport, Wash., is planning the in-
stallation of an eiectric-llghtlng system at
I'riest river.

Boiler house of the Germantown Ice Mana-
facturiag Company, at Belfield avenue and
Haines street, Philadelphia, Penn., was de-
stroyed by fire.

The Barrett Manufacturing Company has
taken out a permit for a boiler bouse to be
t rected at Bermuda and Margaretta streets,
Philadelphia. Penn.

Tlie Bremerton & Charleston Light and
Fuel Company, Bremerton, Wash., contem-
plates installing a power and lighting system
at Port Orchard, Wash.

The Cedar Rapids & Iowa City Railway
and Light Company. Cedar Rapids. Iowa, will
Install two new boilers, one turbine and make
other Improvements to its electrical equip-
ment.

I'lans have been completed by P. O. Keil-
holtz. of Baltimore. Md.. for new 35.000-
liorsepower power plant to l>e erected at Se-
curity by the Western Maryland Power Com-
pany.

\o\. 34

NEW YORK, AUGUST 8, 1911

No. 6

EVER notice the ambling, jelly-fish kind
of individual slouching along the high-
way, his chest sunken, his shoulder
blades sticking out and his head bowed down ?
Sure you did I And you had a strong desire
to steal up from behind and straighten him
up with a drive of your fist ? Sure again !

His ailment is loss of backbone; he cannot
get anywhere in particular, even to going
straight ahead; he does not care; he is inver-
tebrate, spineless.

Let us get oflf the highway for a minute
and approach a little nearer to the "brass
tacks," the power plant.

We will go far before we can discover an
individual who measures down to the pitiful
figure depicted above, but —

More stiffening up of the backbone is highly
necessary these days; the backbone is the
invisible tail to the brahi, and in this in-
stance the "tail should wag the dog."

To succeed, the operating engineer must
be an energetic, thinking, confident man;
the hesitating, indifi"erent and careless man
is being crowcled to the wall, and the demand
for his services will soon be small indeed.

In these free and glorious United States
it is our ])roud boast that one man is as good
as another. Oh, no, he isn't! It is the
jellyfish kind that cannot stifTen up. It is
the one with the backbone who does things.

An operating man may say, when a level-
headed chap has approached the old man
;nul (old liini how a dollar here and there

could be saved by some inexpensive change
of operation, or by adopting a new device
seen in another plant: "Why, I knew that;
I could have told the boss that much, but 1
did not want to butt in; it is none of my
business."

It M' his business, and right here is where
he should butt in, and butt in hard!

Owners and managers are constantly com-
plaining that they hire engineers to operate
their plants who hold aloof and seem afraid
or unwilling to open their mouths.

Open your mouth, then say something!
The boss will not eat you up or discharge
you if you will but hook up your backbone,
increase your mental pressure and "pull
her wide open." Jack up your spine, throw
out your chest, square your shoulders, then
dig out for the old man. He will be glad
enough to see you if you have something
to offer.

Produce something!

Frankly, is it not because some of us
fail to jiroducc something of benefit to good
operating ])ractice that we figure very small
in the estimation of the owners? To be a
good detail man is all very well, but the
performer of details — the usual routine
duties that are taken as a matter of course —
generally goes unrecognized and gets lost in
the midst of them.

Right this minute, you m;iy have a good
economical scheme tucked away just above
your spinnl column. StifTen up, and out

with it to the old in:in '

198

POWER

August 8, 1911

Extension of Redondo Beach Plant

To satisfy the increased demands for
current resultant from the natural growth
in the section served, an extension of
the Redondo Beach generating station of
the Pacific Light and Power Corporation
has just been completed. Redondo beach
is about 20 miles southwest of Los
Angeles. Although much of the power
generated in this station is used in Los
Angeles, the beach is an advantageous
location for the plant because of the
availability of sea water for condensing
purposes. The difficulty and expense of
obtaining sufficient water for this pur-
pose in Los Angeles more than offset
the losses due to the additional distance
of transmission.

The original generating equipment of
the Redondo plant was fully described
in Power for September 15, 1908. Briefly,
it is as follows: Three 5000-kilowatt
General Electric dynamos direct driven
by Mcintosh & Seymour double hori-
zontal-vertical compound condensing en-
gines, 34 and 70 by 56 inches in size,
running at 100 revolutions per minute.
Steam for the engines is generated in
Babcock & Wilcox boilers and delivered
at 175 pounds gage pressure and a super-
heat of about 100 degrees Fahrenheit.

By A. R. Maujer

Tilo i^,ooo-kilovolt-am-
pcre high-pressure turbines
have been installed without
enlarging the engine house.
The circulating-water sys-
tem has been enlarged and
redesigned so that a con-
timunis and ample cooling-
icater supply is perma-
nently assured.

cred. and, in view of the showing made
by the exhaust-steam turbine installation
at the Fifty-ninth Street station of the In-
terborough Rapid Transit Company, of
New York, and the similarity in the
physical characteristics of the Redondo
and the Fifty-ninth Street plants, it was
anticipated by many that the exhaust-
steam turbine would be selected. The
single factor which determined the se-
lection of the high-pressure turbine was
the necessity of having the power for
use within the shortest possible time.

with the reciprocating-engine part of the
station's equipment.

The extension of the plant compelled
remodeling and enlarging the circulat-
ing-water system. In the original layout
the circulating pumps were in a pit at
the west end of the engine room. These
pumps were removed and the new ones
were placed in a separate house down on
the beach, and in the space made vacant
by the removal of the old pumps, two
15,000-kilovolt-ampere Curtis vertical
turbo-generators with their auxiliaries
were installed. Thus the original ca-
pacity of the station was virtually
trebled without extending the engine-
house building lines.

Turbo-generators

The turbo-generators run at a speed
of 750 revolutions per minute and gen-
erate 50-cycle three-phase current at
9000 volts. The voltage is stepped up
through autotransformers to 18,000 volts,
the pressure at which it is transmitted
to the substations. Autotransformers are
cheaper in first cost, and in cases where
there is a simple voltage ratio as in the
present instance, where it is 2 to 1, they
are more efficient than the usual static

Fig. I. The Redondo Beach Steam-generating Station

Each engine is served by two Wheeler
"Adiriiralty" condensers which are
drained by motor-driven Wheeler-Ed-
wards pumps.

After a careful inspection of the plant
and iti equipment and a thorough anal-
ysis of the operating conditions, the con-
sulting engineers, J. C. White & Co., Inc.,
of New York City, decided to recommend
high-pressure turbines. The possibilities
of exhaust-steam turbines were consid-

High-pressure turbines meant the quick-
est job; then, too, if exhaust-steam tur-
bines had been selected, it would have
been necessary to alter the cylinder ratio
of the engines. This means t'lat one en-
gine would have been completely out of
service for a considerable time, and this
was entirely out of the question, for the
load was very close to the station capacity.
It is possible that exhaust-steam tur-
bines may yet be installed in connection

sets. The new exciter, which is a four-
pole 100-kilowatt machine, is driven by a
Curtis two-stage noncondensing hori-
zontal turbine running at 2400 revolu-
tions per minute.

The oil for the bearings is pumped by
three Dean horizontal duplex pumps, two
for normal operation and one spare. Two
pumps are provided for the oil for the
guides and governors; one for normal op-
eration and one reserve.

August 8, 1911

Condensers

The condensers are of the surface type
and are built in two sections; the main
or base section, directly underneath the
turbine, contains 16,000 square feet of
condensing surface; the auxiliary section
forms an extension at one side of the
main section and contains 8000 square
feet of surface. The condensers and the
wet- and dry-vacuum pumps were sup-
plied by the Alberger Condenser Com-
pany. The condensate is removed by a 5-
inch motor-driven centrifugal pump.
There is also a turbine-driven unit of the
same size for emergency use. The dry-
vacuum pumps are steam-engine driven,
10 and 30 by 24 inches in size.

POWER

screens to exclude kelp and other marine
growths from the condensers.

In the southern latitudes submarine-
plant life is extremely varied and prolific
and consequently there is always a vast
quantity of leaves, weeds, etc., in the
water. With this original arrangement
of the intake pipes, these growths were
sucked against the screens and frequently
were pulled through into the pumps. As
a result, the condensing system was
often completely out of service in spite
of the fact that there were duplicate
suction pipes, one of which was always
available for cleaning. It was many
times found impossible to clean one pipe
and get it back into service rapidly
enough to relieve the other pipe before

199

turbine designed to run condensing, how-
ever, approximately 50 per cent, of the
work is done by the expansion of the
steam below the atmospheric pressure,
and the loss of the vacuum would mean
that a large part of the load would have
to be taken off.

The new circulating-water system at
the Redondo station differs radically in
design from the original one. With the
old system the circulating-water pumps
were connected direct to the long intake
siphons and these contained the screens.
Thus the water passed through the
screens under pressure, and once a bit
of seaweed caught against the screens
there was little chance of its floating
free again until the suction was taken

Fir,. 2. Partiai View of Generator Room, Sh" >

CiRCULATINC-WATER SYSTEM

Originally, the circulating wafer was
drawn through either or both of two
50-inch riveted-steel suction pumps some
1300 feef long to the three pumps.
These forced it through the condensers
from which it was discharged through
a .^0-inch return line of construction
similar to that of the intake pipes.
The suction lines extended out from
the shore about 7000 ft. At the shore
each line connected into a large cyl-
indrical chamber containing a set of

if became so badly fouled and the cir-
culating-water supply so reduced that if
was necessary to divert the engine ex-
haust to the atmosphere.

Continuity of condensing-wafcr supply
is most important in the case of a tur-
bine installation. A reciprocating en-
gine, which normally operates condens-
ing, is capable of carrying at least its
rated load even when the vacuum is lost,
as less than 25 per cent, of the work is
done by the expansion of the steam be-
low the atmospheric pressure. With a

off. In the present systcin the siphons
discharge into an open screen basin con-
taining racks and screens of ample area
and so arranged that cleaning is easily
accomplished; the water is cleared of the
seaweed under atmospheric pressure
alone. Fig. 3 shows the general arrange-
ment of the intake portion of the pres-
ent circulating-water system. The new
house which contains the circulating-
water pumps is located close to the shore
line of the hcach. On its seaward side
is the screen basin in which the pump-

200

POWER

August 8, 1911

suction pipes extend and from viiich
the siphon pipes are carried some 950
feet out on a reinforced-concrete pier to
deen water. The siphon pipes are 54 inches
'" diameter and are built of ^4-inch steel
plates. The longitudinal lap scam is
double riveted with .)4-inch rivets on 2;4-
inch centers. The circumferential lap
seams are single riveted with -H-inch
rivets on I7,.s-inch centers. At their sea
ends the siphons connect into seven 26-
inch fuction nozzles 22 feet long, spaced
as sliown in Fig. 3. The total area of
the suction pipes is over 50 per cent,
greater than that of the main pipe, and
conscouently the velocity of the water as
it enters the intake nozzles is low. This
prevents undue agitation of the water in
the vicinity of the intakes, and there-
fore less seaweed gets into the siphons
than would otherwise be the case. The
screen basin is built of reinforced con-
crete. It is 58 feet long, 52 feet wi
and .31 feet deep from the top of the
side walls. Two partition walls extend
across the basin at equal distances from
the ends and divide it into three bays o
equal size; one siphon and one pump-sue
tion pipe enter each bay. These wa

L-=^il^-)L

-^-J-^-^^P

r i°i,f^ "I

I'V^ h,,:;' Jl-

loy^i -oi

-I iv 1^;^ ji^

.. l^^^^T'ol'-.

---\.'o -],'r. .;|;-^

\-<i\

— tl — h -

driven by a 15-horsepower motor, has
ample capacity to keep the pipes free
from air. The siphons will run approxi-
mately two hours without any assistance
whatever from the vacuum pumps.

The air tap from the siphon is car-
ried up vertically for 34 feet, so as to
eliminate the possibility of the vacuum
pumps pulling over a slug of water into
their cylinders and wrecking themselves.
All of the entrained moisture in the air
is retnoved by a Cochrane separator at
the top of the air seal. The vacuum
pipmg is in duplicate.

In the screen basin the water first
passes through sets of iron racks, in-
clined at an angle of about 45 degrees

and prevents it from getting back into the
water on the suction side of the screens.
The seaweed and the cleaning water fall
into a trough and drain off outside the
screen basin, the flow being helped by the
discharge from a 6-inch centrifugal sand
pump. The suction of this sanJ pump
is placed on the bottom of the screen
basin in such a manner that whatever
sand is brought in through the siphons
is promptly removed. By this ar-
rangement a screen can be raised,
cleaned and replaced in a very short time
w'ith but a small expenditure of labor.

Water for flushing off the screens is
supplied by a 10 and 5 by 10-inch Worth-
ington duplex pump controlled by a

Splashboard

F. I e V a + i o n .
Fig. 3. Showing General Akrangement of Siphons and Screen Basin

being inverted trusses, strengthen the
bottom of the basin, which rests on
quicksand, and provide suitable means
of holding the screens and racks in
place, which are thus made in sizes
small enough to be handled with fa-
cility. Two holes in each wall serve
to keep the water level equal in all of the
bays and thus prevent any lateral strain
on the walls.

The water is induced to flow into the
screen basin after the n^anner of a
natural siphon. A vacuum-pump line
for keeping the siphons free of air is
connected through an 8-inch nozzle to
each line at A, Fig. 3. Several motor-
driven vacuum pumps of assorted sizes,
which are in the pump house, are con-
nected to this line. One of the large
pumps is used for starting the water.
During normal operation a small pump.

to give plenty of submerged surface.
These racks are made of 3x'4-inch iron
bars placed ^s inch apart. Behind the
racks are two sets of vertical screens
and provision has been made for a third
set. The front set is made of No. 8
galvanized-iron wire cloth of ~s-inch
mesh, and the rear set of No. 10 wire
with >i-inch mesh. The framework of
the screens is made of angle iron. The
screens fit into slots and are provided
with rings in their upper edges so that
they may be raised easily by the small
electrically operated traveling crane
shown in Figs. 3 and 5. When a screen
becomes fouled it is raised, swung in
front of the splash board, also shown in
Figs. 3 and 5, and flushed off from the
back w'ith a hose. A trough at the bottom
of the frame catches any seaweed that
mav fall from the surface of the screen

Fischer governor and placed as shown in
Fig. 3. This pump also supplies water
for the 30-inch hydraulically operated
valves on the circulating-water pumps.
In case of emergency these valves may be
operated by w-ater from the boiler-feed
pumps.

The circulating water enters the pumps
through 36-inch lap riveted-steel suction
pipes. The pumps are of the double-
suction centrifugal type and were built
by the G. W. Price Pump and Engine
Company. The diameter of the inlet Is
32 inches and that of the discharge 30
inches. Each pump is capable of passing
24,000 gallons of water per minute
against a total head of 40 feet when
working at a speed of 225 revolutions
per minute. The pumps are driven by
Fleming- Harrishurg tandem -compound
noncondensing side-crank engines, 16

August 8, 1911

POWER

201

and 27 by 18 inches in size, controlled
by Gardner throttling governors. These
engines are rated at 400 horsepower each.

There are three 50-inch reinforced-con-
crete circulating-water pipes, one for each
turbine unit and one for the three engines.
Just outside the pump house these pipes
are so interconnected by a manifold that
Ihe discharge from any pump may be
put through any line. The circulating-
water discharge from the various con-
densers is collected in an 11 by 18 by
20-foot concrete hotwel! from which the
water flows away by gravity through a
reinforced-concrete duct 5 feet square.

The exhaust from all of the auxiliaries,
including the circulating water-pump en-
gines, is piped to the two new 10,000-
horsepower Cochrane open feed-water
heaters which are on a gallery in the
new part of the boiler house, as shown
in Fig. 7.

The square concrete tank on the floor
in the foreground of Fig. 7 is an auxil-
iar>' hotwell. Originally the condensate

the auxiliary hotwell was provided, and
now the condensate is collected here and
then pumped to the heaters. The over-
flow from the heaters is also received by

sary to extend the boiler house approxi-
mately 100 feet and erect a chimney sim-
ilar in design and equal in size to the
two old chimneys. The new chimney,

Fig. 4. Bikj^Li t; \iE.\ of Pimp House, Screen Basin and Siphons

this hotwell so that no water suitable for of reinforced concrete, is 125 feet high
boiler feed is wasted. and has an internal top diameter of

13 feet. The new boilers are fitted
with Babcock & Wilcox superheaters
To provide the extra steam required which give the steam a superheat
for the two new generating units, pro- of 100 degrees. Three Hammel back-

Ne>x' Boilers

Fic. 5. LooKrNC Into Screen Basin

from the Mcintosh & Seymour engines
was discharged into individual hotwclls
from which it was pumped to the heaters
as needed. In cases of sudden overload
on the engines these hotwells would over-
flow to the sewer and considerable good
water was lost thereby. To avoid this,

vision was made for the Installation of
eighteen 600-horsepower Stirling water-
tube boilers. Eight of these boilers have
been erected so far and the erection of
the remainder will be completed in the
immediate future. To accommodate this
additional boiler equipment it was neces-

shot fuel-oil burners are used under
each boiler in Hammel furnaces. The
burners under the new boilers are hand
regulated while those under Ihe original
boilers, also of the Hammel make, arc
all automatically controlled by the sys-
tem devised by C. C. Moore & Co. Thus

202

POWER

August 8, 1911

the new boilers are set to work at their
most economical rate, while the old auto-
matically controlled boilers take care of
the load fluctuations.

Piping

The high-pressure piping is constructed
of full-weight steel pipe with Van Stone

blowoff-pipe lines are of full-weight steel.
The boiler-feed pumps are of the usual
duplex type.

Value of a \'acuum
For some weeks a discussion has been
running in The Engineer, of London, upon

high vacuum, and in an editorial review
of the discussion The Engineer reaches
the conclusion that Mr. Morison has
proved his case, and that in all but a
small percentage of ships good vacuums
are worth having. In the best practice,
however, the gain can be but little. If
the price to be paid for the apparatus

' Fic. 6. Interior of Circulating-water Pump House

joints of forged steel. Long-radius bends the value of a vacuum, induced by a. required to utilize the auxiliary exhaust

are used throughout the entire high-pres- paper by Mr. Morison, whose recent work and get rid of air from the condenser

sure steam-piping system. All of the upon the condenser has been several is small, then the capital outlay may be

high-pressure steam-pipe fittings are of
cast steel. The boiler-feed and boiler-
washing piping are built of cast-iron pipe
having a wall thickness of J4 inch. The

The Feed-water Heaters and the Auxiliary Hotwell

times referred to in our columns. Mr.
Morison in his paper rather questioned
the current opinion of marine engineers,
that it is better to run on a low than a

regarded as a good investment. The first
thing to be demonstrated was that hot feed
water and a good vacuum may go together.
Of this there is no longer any doubt.

August 8, 191!

POWER

Bleeding Receiver to Heat Feed Water

A correspondent submits the follow-
ing inquiry:

"I have a 22 and 44 by 72-inch tan-
dem-compound engine. The steam pres-
sure is 140 pounds, gage; the vacuum
is 25 inches. The engine runs at (51.5
revolutions per minute carrying a load
of 670 indicated horsepower. The re-
ceiver pressure is 9 pounds, gage. The
temperature of the feed water is 100 de-
grees. Can I install a heater and use
steam from the receiver to raise the
water to 210 degrees for 850 boiler
horsepower, and what would be the sav-
ing in coal?"

Assume the required evaporation to be

30 X 850 = 25,500 pounds

at 155 pounds absolute.

To make a pound of steam at this
pressure from water at 32 degrees would
require 1194 heat units. To raise a
pound of water from 32 to 100 requires
67.97 heat units. To make a pound of
steam therefore at 155 pounds absolute
from feed water at 100 degrees would
take

1194

67.97

1126.03 B.t.u.

and to make the 25,500 pounds required
would take

25,500 X 1126.03 = 28,713,765 B.t.u.
all of which with the feed water at this
temperature the coal would have to fur-
nish.

In the absence of indicator diagrams
assume that with the given receiver pres-
sure of 9 pounds, gage, or 24 pounds
absolute, the steam when it gets to the
receiver has done one-half of the work
which it is capable of doing; that is,
that it will do as much work in the low-
pressure cylinder as it has already done
in the high. Assume that the engine
requires 15 pounds of steam per indi-
cated horsepower-hour, that the cylin-
ders are equally efficient and that the
s»eam as it enters the high-pressure
cylinder is dry saturated.

One horsepower-hour is 1,980,000 foot-
pounds, or

1,980.000 , , ,.

777-52
Each pound of steam then gives up as
work in the whole engine

2546.6 H- 15 = 170 B.l.u. (approx.l

and in the high-pressure cylinder one-
half as much or

170 -^ 2 - 85 n.l.u.

One pound of dry saturated steam at
155 pounds absolute contains 1 194 Bt.u.
Neglecting radiation, each pound would
carry to the receiver

1194 — 85 — 1109 R.t.u.

Co])!pntatio)is sluncnig lunc
a saving of 4,74 per cent,
of the heat in the steam
■}nay he saved, theoretically,
by using steam from the
receiver to raise the feed-
wafer temperature from 100
/i> no degrees Fahrenheit.

The "heat of the liquid" at the re-
ceiver pressure, 24 pounds absolute, is
206 B.t.u. This would leave

1109

206 = 903 B.t.u.

94.7 per cent.

available for evaporation.

The heat necessary to evaporate a
pound of water at this pressure is 953.5
B.t.u. Therefore, only

95,V.S

of the exhaust from the high-pressure
cylinder can be steam, and less will be
on account of radiation and conduction.
In the receiver some of this moisture
may settle out and be drained off, and
the question may be complicated as to
the use of these drips and the quality
of the stuff taken out of the receiver.
Let us consider the simplest case, tak-
ing the mixture from the receiver as it
comes from the high-pressure cylinder,
each pound containing 1109 B.t.u.

It is desired to raise the temperature
of the water to 210 degrees. The heat
in a pound of water of this temperature
is 178 B.t.u. In passing to water at
this temperature the pound of mixture
which is taken from the receiver will
give up

1109 — 178 -, 931 R.t.u.

To raise a pound of water from 100
degrees to 210 will take 110 B.t.u.

It

ill. therefore, take - of a pound
9.3 1

of the receiver mixture to heat a pound
of the water the required amount.

But it is not necessary to heat the
whole of the feed water 110 degrees.
A part of it will be made up of the con-
densed steam at 210 degrees coming
over from the receiver.

On the other hand, the boilers will
have to evaporate more water because
the steam taken from the receiver will
have done only one-half of its work,
and the boilers will have to supply one-
half as much as is taken out in addi-
tion to what they have been supplying
to make up for the loss of the work in
the low-pressure cylinder.

Call the amount of 100-degree water
necessary to be heated .v.

T-l . 1 1 o - , - .

ihen, smce — of a pound of mixture
9.^'
will come out of the receiver for each

pound of water heated, — x will be the
931

weight of the mixture taken from the re-
ceiver, and

, 1 10

V -f- - _r
9,U

will be the total amount of water fed to
the boilers. This must be 25,500 pounds
plus one-half as much as is taken out
of the receiver or

, / I 1 10 \
+ ( - X — x)

so that
X 4-

931
I 10

25.500 -f

2 X 931

= -'5,.SOO

93 ' 2 X 93 1

/ ,110 no \

n'+^t-97nr;)=^5,5

X = „ = 24,077 pound.

1.059085

Let us see how this comes out:

B.t.u. from re-

24.077 poimd.s lo be heated
110 B.t.u. per pound

- per lb. 931 ■) 2,648.470 B.t.u. needed

2,843 pounds from receiver
24,077 new water

26,022 tol 1

The boiler now has to evaporate 26,-
922 pounds of water at 210 degrees into
steam at 155 pounds

Total lieat at l.i.i pounds - 1191

Heat of liquid at 210 degrees = 178

B.t.u, required per pound = 1016

The fuel will have to supply then
26,922 X 1016 = 27,352,752 B.t.u.

per hour
In the original condition it had to
supply 28,713,765.
The difference:
28,713,765 — 27,3.52,752 ^ 1,361.013

1,161,013 X 100

2^.713,765

4 74^'

In case of low water, smother the fire
immediately with green coal. Close the
ashpit doors. Open the damper, allow-
ing cool air to draw through the furnace
and tubes. Leave the engine running
until pressure is reduced to the lowest
possible point. If the feed pump is run-
ning let it run as long as it will. When
the pressure will no longer run the en-
gine or pump, it may be still further
reduced by opening the gage cocks and
the wafer-column drain valve. When
the pressure has been reduced to near
the atmosphere, water may be let in to
the usual highf and a search made for
leaks or signs of overheating.

204

POWER

August 8, 1911

Mean Pressure of Expanding Steam

To estimate the work done by steam
in a cylinder working at full pressure
against a piston during part of the stroke
and then, being cut off from the boiler
supply, expanding for the remainder of
the stroke, it is necessary to know the
average or mean pressure exerted against
the piston throughout the stroke. If A
is the area of the piston in square inches,
L the length of stroke in feet, and p,n
the mean pressure in pounds per square
inch, the work done for one stroke is
W = A X L X Pm foot-pounds

The value of the mean pressure is ob-
tained by the formula

(I + hyperbolic loq. r\ ^ .
~r ~) ^''

in which

/i, = Absolute initial pressure;
pm = Absolute mean pressure;
r = Number of expansions, or
Volume after expannnn
Volume before expansion
Since one volume of boiler steam be-
comes r times larger at the end of the

stroke, it follows that the cutoff is -.

The effective mean pressure, however,
is not the pm given by equation ( 1 ) ; to
obtain this, it is necessary to subtract
from Pm the absolute back pressure.
Even then, there are many other factors
which may affect its value, such as a
variation of pressure in the receiver,
friction in the steam ports and passages,
initial compression at the beginning of
the stroke, etc. To calculate the in-
fluence of these various elements would
be laborious, involving many assump-

By Albert E. Guy

By means of the alinevient

chart herein given, it

is

possible to read directly

the

value of the expression

for

the mean pressure when the |

initial pressure and

the

number of expansions

are

k)iown.

•Si-i. .\pril 4 issue of I'owni:.
tSee June 0 issue 01' I'oweh.

found to suit the purpose more close-
ly than these tables; it gives the re-
quired mean pressure at one reading
without any further calculations except,
of course, those involved by the use of
a coefficient of correction, as mentioned.

It should be noted that - represents

the cutoff', but not that usually under-

The modulus* m, for the r scale was
chosen 250 millimeters, the same length
being suitable for the modulus m, of the
scale of p,.

Equation M7)t gives for the modulus
m~ of the pm scale:

And since m ;= m,,

m-, m, 2 so -II- J

TO, = := — ' = ^^ =125 millimeters

2 ;«! 2 1

The chart is constructed as in Fig. 1.

d »n ,

e jn.
The pm scale is therefore exactly
equidistant from the other two. For pi

r, rp r, C

\ 1

\"3

\

\

tions, and the result would be doubtful.
Therefore, it is preferable to employ
suitable constants derived from experi-
ence. These may be found in many en-
gineering handbooks which also give
tables of values for the expression
4- hyperbolic top. r\ _,

— )■ The alinement

r

chart herein given, however, will be

Fig. 2

stood in engine practice. In the latter
case

poiiion of stroke during admission

" full length of stroke

whereas,

I volume of steam before expansion

r volume of steam after expansion
If there were no clearance space these
two values would be equal, but. actually

(portion of stroke during admission\
+ clearance /

r length of stroke -j- clearance

The scales of r and - in the chart do
r

not represent the values of r and -, but

r
■ i J ^u 1 . f I -\- hyperbolic loQ.r\

mstead the value of ( — ■ — ^-^ — j

for a given value of r. Thus where r
equals 10, the chart reading represents in
reality the value of 0.3303.

Fig. 3

the scale of numbers on a 10-inch slide
rule can be used, and for pm the scale
of squares on the same rule.

The scale of r was determined as fol-
lows: On the line AB (Fig. 2)
and from A as an origin, the logarithmic
lengths A a,. A a=, A a,, etc., were laid
off. being the values of the expression

(I -^h\pcrbolicloij.r\ . ,._ ^ ,
^ - ^ = — j for different values

of r, respectively r,, r.., rs, etc. Then on i4 C
normal to A B, and from A as an origin,
the logarithmic lengths of r,, r:, r,. etc.,
were laid off, and the rectangular co-
ordinates fli d, — n di, a-, d: — r= d-, a- di
— r- d , etc., drawn as shown. This de-
termined exactly the points of intersec-
tion rf„ d., d,, etc., through which the
cur\e A D was made to pass.

A sufficiently large number of intersec-
tions was plotted so as to insure the
correctness of the cur\'e. The remainder
of the work required only close attention
and patience, it being altogether mechan-
ical. Fig. 3 shows how the scales were
transferred from A C to the curve A D,
and thence to A B.

The scale of initial pressures extends
from 25 to 250 pounds. Should a higher
pressure be used, as 360 for instance,
with r equal to 10, a straight-line index
place on 10. on the r scale, and on 36,
on the p, scale, will determine on the pm
scale a mean absolute pressure of 11.9
pounds, which multiplied by 10 (since
36 X 10 = 360) gives 119 pounds as
the required mean pressure.

August 8, 191 1

POWER

205

r

c

0

0

tn

in

c

L

c

a

X

lU

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\

L

v

0

(t

Q)

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t)

(U

F

t

D

D

r.

O

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II

C

o

c
o

D-
X

U

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0.200

o.7S?a

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o./So

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o

u./io

+-

c

v.fSo

o

-I o.aHo

— — t^f*^

CT

Zoo.
/So.

^^_

Cmart No. 4

If nny two of tli<> tliroo fnclorn ropfopntml liy fhc xcnlpii nro known. Ilw
third mny lio foiinil l>y pinKini! fl «iralBlit linn Ibroueh th^w qunnlltli'n on tlidr
rf«p<''llvo nrnlin. Tlil« lln-' will InltTwot tlio third urnlc at the niinilHT
reprpfiontinK th«' «l''*>lrnfl fnrtor.

00

O-

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7S-

JS.

So-

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-Ac_

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43«__i

,?.}■

POWER

August 8, 1911

Errors of Indicator Reducing Rigs

The indicator is an instrument whicli
will give a graphic representation of the
whole cycle on one side of the piston,
thus permitting a study to be made of
all the variations of pressure and vol-

"h®^-

-^l

'k^'

-45--

Lever RcDiiciNr, Motion and Diagrams
Comparing Errors Due to Its Use

ume through the stroke and giving a
means of calculating the work done by
the steam upon the piston.

To obtain an exact representation of
the conditions on the inside of the cylin-
der it must exhibit with precision the

^^^^

LiVEK WITH SlIDING-PIN CONNECTION

ANii THE Diagrams Showing Errors

By E. S. Libby

III an efjurl to make the in-
dicator produce a diagram
which represents exactly the
motion of the piston within
the cylinder, many forms of
reducing motion have been
devised. The shortcom-
ings of some of these are
herein pointed out.

pressure of the steam within the cylinder
at every instant throughout the stroke,
and simultaneous measures must be
given of the position of the piston cor-
responding to the given pressure each
instant; the diagram produced must be
made so as to have its ordinates exactly
proportional to the steam pressure and
its abscissas proportional to the motion
of the piston.

"®K

■fr'

,\ B

~V'

Fig'. 5

1 ■' 1

Telescoping Lever and Diagrams Show-
ing Errors

In obtaining an exact reproduction of
the motion of the piston the reducing
motion must be so designed as to im-
part to the drum of the indicator a mo-
tion proportional to that of the piston.

The reducing motion is made in many
ways and is often improvised for the
occasion by ingenious engineers. The
accompanying sketches illustrate some of
the different rigs used.

The reducing motion shown in Fig.
1 consists of a lever A B, slotted at the
lower end, which permits the pin D in

the crosshead to work up and down as
the crosshead travels from F to G. The
indicator cord is attached to the point B'
and may be led direct to the indicator
or over a pulley H to the indicator.

Jointed Lever, Brumbo Pulley and
Diagrams Showing Errors

In all motions of this kind there is
a radical defect due to the fact that
while the crosshead moves in a straight
line, any point on the lever swings
through an arc of a circle. With this re-
ducing motion the error produced is il-
lustrated in Fig. 2.

The diagram a represents the true dia-
gram; b the diagram obtained if a sector
were substituted as in Fig. 9, in place of
running direct from the pin B'. This
shows an error of 0.95 per cent, too high
in mean effective pressure. The diagram

Fig: 10

Pantograph Reducing Rig

c represents that taken without a sector
but running direct to the indicator. The
cord is usually so long that its angular
motion is immaterial, showing an error
of 0.6 per cent, too high in mean effective
pressure. If, however, the cord is run
over a pulley as at H, the distortion

I

August 8, 1911

POWER

207

will be quite marked, as will be seen
by the diagram d which shows an error
of 1.5 per cent, too low in mean effective
pressure.

The motion illustrated in Fig. 3 is the
same as that shown in Fig. 1 with the
exception of the slot, which is on the
crosshead. the length of the lever remain-
ing constant. With this reducing rig the
errors introduced by its use are illus-
trated in Fig. 4.

The diagram a is the true one; b made
as before, with the sector, shows an error
of 0.68 per cent, too low in mean effective
pressure; c made as before without the
sector but with the cord running direct
to the indicator, shows only 0.25 per
cent, too low in mean effective pressure;
d, with the cord running from the pin B'
over the pulley H to the indicator, shows

s^-'N;-

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r

^'^y^^*^

rx^/^ I

Sl*o\ \

^"'^^^

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Fig. 11

^y^y

^^,,^^<^'

qI !< -d

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EH

Fig. IE

Pl>,v

Another Form of Pantograph and

Corresponding D

ACRAM

s

an error of 2.7 per cent, too low in mean
effective pressure.

In Fig. 5 the reducing motion is a
combination of the two already explained.
Here the top part is permitted to slide
inside of the lower part. With this form
of motion it will be seen that the error
is more marked.

In Fig. 6, a represents the true dia-
gram as before; c the diagram obtained
by running direct to the indicator drum.
Here there is an error of 4.8 per cent.
too low in mean effective pressure. If
the cord is run over the pulley and then
to the Indicator the diagram d is obtained
with an error of 7.4 per cent, too high in
mean effective pressure.

The rig shown in Fig. 7 is known as
the brumbo pulley and is probably used
more than any other form, especially
these already illustrated. The diagrams
obtained with this motion are shown in
Fig. 8. a being the true diagram, b that
obtained with the use of the sector, show-
ing an error of 0.55 per cent, too high In

mean effective pressure, c being the dia-
gram obtained without pulley or sector,
showing no error which could be meas-
ured and that would affect the mean ef-
fective pressure. The diagram d is ob-
tained by running the cord from the pin
over the pulley to the indicator, and i;
shows an error of 0.95 per cent, too low
in mean effective pressure.

Figs. 10 and 11 represent two well
known forms of pantograph, which give
an exact reproduction of the motion of
the piston, provided the indicator cord is
run parallel to the path of the piston. If
the cord is not run from the pantograph
parallel to the piston but run over a pul-
ley, as shown in Fig. 1 1 , we have the
results shown in Fig. 12 by diagram d
which shows an error of 2.3 per cent,
too high in mean effective pressure.

The amount of distortion varies also
with the location and the size of the
pulley H. The larger the pulley the more
distortion, and the higher the pulley is
above the point of suspension A, the
more distortion. If the pulley were
placed directly above and at an infinite
distance from the point A the motion
would be zero.

The foregoing is based upon the fol-
lowing data: Stroke of engine, 18 inches;
distance of the point A above the center
line of engine, 20 inches; distance be-
tween A and H, 6 inches, and diameter
of pulley H, 6 inches.

Speed versiKs Economy of

Engines

By Vincent Clarke

Engine builders often find that speci-
fications call for a piston speed or a
certain number of revolutions per minute
lower than the standard adopted. The
standard line of engines is usually de-
cided upon after careful consideration
in order to get the most economical type,
and when dealing with inquiries for en-
gines not coming within this range the
standard engine Is usually offered at a
suitable speed.

For example, a 400-horsepower engine
may be required to run at a speed of 90
revolutions per minute. If the standard
line of engines were of the medium-
stroke type and there were no restric-
tions regarding the speed, the engine
builder would offer a 15 and 25 by 27-
inch engine at a piston speed of about
800 feet per minute, or 170 revolutions
per minute. As the speed is limited to
90 revolutions per minute this engine
would not develop the power, and the
suitable standard size would be an 18^4
and 31 by 33-Inch engine.

This engine would be designed for a
piston speed of about 800 feet per min-
ute and about ISO revolutions per min-
ute. Hence the maker would have to
offer an engine running at 40 per cent,
below the speed for which it was de-

signed. If the steam consumption of this
engine must be guaranteed under these
conditions, then the effect of diminish-
ing the speed has to be considered.

So far as the writer is aware, the
only published information on the effect
of the speed of rotation on the economy
of an engine are the tests made by P. W.
Willans and recorded in volume 114 of
the Proceedings of the Institution of
Civil Engineers; the actual figures of the
tests were 17.3 pounds per indicated
horsepower per hour when running at
400 revolutions per minute, and 17.6
pounds when running at 300 revolutions
per minute. Thus for a 25 per cent, de-

%.-■

1 1

■300 Fey permit

-

1

8^0

" - -

"^^

10

15

?0 25

30

Meon Effective Pressure. — •

Pounds per Square Inch

Fig. 1. Results Up to 25 per Cent.
Decrease in Speed

crease in the speed of rotation there was
an increase of 1.7 per cent, in the steam
consumption.

The writer recently conducted some
tests with a double-acting engine to ob-
serve the effect of the speed of rotation
upon its economy. The engine was of
the triple-expansion type, the cylinders

v„

1

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l" 1

=

10

15

SO 25 30 35

Meon Effect. yc Pressure, '*-'*

Pounds per Square IncH

Fic. 2. Results with 40 per Cent.
Variation in Speed

being 12':-, 18' 5 and 30':. by 12 inches,
and the range of speeds covered all
those which were likely to be required.

Fig. 1 shows the results In pounds of
steam per Ind cated horsepower per hour
plotted against mean effective pressure.
From this it is seen that with a 25 per
cent, decrease in the speed of rotation
there is about 1.5 per cent. Increase in
the steam consumption, this increase be-
ing practically constant at all loads.

The writer recently gave a close steam-
consumption guarantee, under penalty,
for an engine under conditions similar
to the foregoing example, and noted the
effect of this 40 per cent, variation in
speed upon the economy.

This engine was expansion-governed,
and tests were made at three different
loads at 150 and at 90 revolutions per
minute. The results of these tests are
shown in Fig. 2. With the 40 per cent,
decrease in speed the steam consump-
tion increased 2 per cent, this increase
being practically constant at all loads.

208

POWER

August 8, 1911

The Price Water Current Motor

Into various models of the ''wave
motor" many American dollars have
found their way, the subject of fuelless
and so called perpetual power generation
surely appeals to a certain class of in-
vestor The "wave motor" now seems
destined to be relegated to obscurity by
a sister invention — the "current motor" —
hailed (by its promoters) as "the marvel
of the age." With this device, we are
fold, all rivers and streams can easily
be harnessed, we can develop power
from such flowing waters with no fuel
and with no expense after installation
and perpetually, night and day, rain or

Fic. 1. Front View of Model

shine, summer and winter. This sounds
good, but — ?

With a patent dated March 1, 1910,
the Price Current Motor Company, of
Los Angeles, has constructed a working
model of its invention and placed it on
exhibition for prospective investors. The
current motor is shown in the accompany-
ing figures. It lays claim to being the
"most remarkable power invention ever
conceived, destined to revolutionize pres-

A device, consisting of a
floating fitime carrying sub-
merged water wheels with
lunged vanes and designed
la convert the energy of
flowing streams into useftd
power. At present, how-
ever, it has materialized
only to the extent of a model
and its achievements are
based entirely upon the in-
ventor's claims.

suit the waterwheels A, Fig. 3. These
wheels have hinged vanes which are
positive in action, being placed, held
and thrown out of position solely by the
agency of the current, thus offering no
noticeable resistance to motion on the
one side. As shown, these four wheels
transmit power, by means of the shafts

as may be desired; its size it is pre-
sumed, is dependent upon stream condi-
tions.

It is stated that no difficulty will be
experienced with ice. First, the ballast
mentioned will keep the wheels below
the ice line; second, the motor is so con-
structed in front to act as a debris and
ice deflector; third, the intake being about
five times wider than the outlet, and
the water traveling through the flume
having a faster rate than the natural
current, will have a tendency to keep
the flume cleared; thus the same efficiency
is attained in winter as in summer.

It may not be amiss to mention the
reason why the public should invest in
this enterprise (per the promoters), al-
though this theme is getting time-worn
through constant application:

"Because it will yield greater profits
with less risk than any other enterprise
that can be mentioned. Because of the
larger profits and the immense dividends
which must result therefrom, based on
the great demand for it, that is sure to
follow its introduction. Because the pos-

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111

m
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It---

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m

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kL

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POwtn.

Rear View of Model

Fig. 3. Plan and Section of Floating Motor

ent methods of generating current, and to
make a fortune for its stockholders."

The motor, based on water in streams
carrying great power, is a floating flume
device, rising and falling with the
action of the current. It is anchored at
the front in three places; by means of
ballast in air-tight compartments, it can
be submerged to a proper depth to

B and C, Fig. 3, through a system of
bevel gearing at D and £, actuating the
flywheel F. The layout of the generating
equipment, placed in a V-shaped house,
is arbitrary with conditions — in this in-
stance it is with countershaft drive to
the generator (from working model).
This apparatus may be constructed of
wood or steel sheeting on a wood frame.

sibilities embodied in this enterprise are
such that they will surprise the most
optimistic. Because we now offer you a
chance to obtain a safe investment, with
the prospect that your outlay should be
multiplied and increased a great many
times."

All of which sounds pretty good,
but—?

^uguKt 8. 1911

POWER

209

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Installation of Small Stationary
Engines

By John S. Leese

When the site for the erection of a
stationary internal-combustion engine of
any type is under consideration, the fol-
lowing points must oe very carefully con-
sidered :

The nature of the ground where it is
proposed to place the foundation; the
likelihood of annoyance to neighbors due
to the noise or vibration of the engine;
the possibility of damage to property due
to the vibration of the engine; the allow-
ance of sufficient room all around the
engine for woricing on it, cleaning, etc.;
the convenient location of the engine
with respect to the machinery it is in-
tended to drive; ease of conveying the
heavy parts of the engine and equipment
to the site; the availability of a constant
and adequate water supply for cooling
water or, if the supply be not reliable
or adequate, the space necessary for the
erection of a cooling tower or circulat-
ing tanks; location of air intake and
protection of surroundings from the ex-
haust gases and heat.

Foundations — The first care that must
be taken in the sinking of an engine
foundation is with regard to the depth
to which it must be carried si. that it
may rest en a really firm bed. For this
reason "made" ground or ground that

Fig. 1. "Insulated" FouNOArroN

contains much sand, rubble or soft clay
is unsuitable for the purpose. If the en-
gine is to be erected on an upper floor or
upon a raised ground fioor It is, of
course, necessary to make sure of the
ability of the floorini; to take such extra
loading without liability to failure or to
distortion which might damage the build-
ing. In few cases is ir advisable lo carry
the foundations below the ground-water
level, owing to the extra expense in-
volved by doing so.

Vibration troubles -It may be found
necessary, if the engine room is close
to dwelling houses or offices, to mount

costs. If direct coupling is out of the.
question, a straight drive by belt, rope
or chain, with the luxury of a clutch, if
possible, is far preferable to spur wheels,
bevel gears or oblique friction drives
Idler pulleys should be avoided if belt
drive is used, unless it is impossible to
get sufficient driving-surface contact on
the work pulleys without them.

Delivery and Erection of Parts — In
opening up new countries the transporta •

the engine on what is sometimes known
as an insulated I'oundation; that is, a
foundation which is separated from the
surrounding earth by a gap which may
be filled in with waste or cocoa-nut mat-
ti..g or some similar material to deaden
vibration. Fig. 1 illustrates this con-
struction. It may also be necessary to
bury the muffler underground so that
annoyance from the exhaust shall not
arise.

The insulated foundation is also ad-
vantageous for preventing damage due to
constant vibration. The writer knows
of a case where, owing to the location
of a rather small oil engine on the first
floor of an infirm.iry, it was necessary
to deaden the vibration at al'. costs. This
was successfully* accomplished by insert-
ing rubber pads, each 6 inches square by
2 inches thick, on each side of each of
the six foundation holding-down bolts
and between the engine base and the
foundation, as indicated in Fig. 2.

Accessibility of llngine — The ease with
which the vital parts of the engine can
be got at will form, in many cases, a
good criterion of the condition in which
the engine will be kept. Engine at-
tendants as a class are not particularly
well remunerated, and if the engine is
not easily accessible, they will not bother,
in most cases, to keep it tuned up or in
any better condition than is barely nec-
essary for it to carry the load. The
starting up of engines in cramped spaces
is frequently not only a most difficult
but also a very dangerous proceeding,
especially in those cases where the op-
erator has to "pull over" with the fly-
wheel or by the belt. The belt should
never run so near the wall that if can-
not be put on or removed without diffi-
culty, owing to lick of space. All
handles, control 'evers, oil cups, etc..
should be get-at-able without the neces-
sity of the attendant being a contortionist.
Filters and other parts which require
frequent cleaning and adjustment should
also be easily accessible.

Location in Respect lo Drive Com-
plication of drive i? to be avoided at all

Fir. 2. Rubber Pads under Engine Bed

tion of heavy pans of machinery to their
destination is often a matter for much
tearing of hair and gnashing of teeth.
It is also frequently found that even in
settled countries an engine buyer has
erected the engine house without any
thought as to whether or not the ma-
chine will go through the door. Often a
part of a wall has to be pulled down to
admit a bedplate or an engine bed; in
one case, where the writer was putting in
an engine, he arrived to find that the
demolition necessary to admit the ma-
chine was so serious that the whole wall
had to be underpinned and afterward
practically rebuilt. Stairways are too
often a cause for trouble to the erector
and underground or basement installa-
tions are extremely ^ifficuit lo make. It
is a not infrequent occurrence for the
owner of the engine, when ii has been
safely put in, to prevent its future re-
moval by erecting buildings and making
alterations in the path. The installation
of a new machine in an old engine room
and the removal of its predecessor is
frequently a hard job for the erector for
this reason.

Water Supply .\s. a general rule it
will be found too expensive to use city
water for engine-cooling purposes. If
there is no river or private supply at
hand, it will be found advisable to erect
a cooling tower on approved lines or else
to install circulating tanks for cooling
the water. These tanks should not be
located in the engine room or in the

210

POWER

August 8, 1911

sunshine; wherever it is possible they
should be put in an exposed and drafty
place. Radiators are largely used in
Germany for cooling the jacket water
but the first cost is greatly in excess of
that for tanks. The advantages of radi-
ators are that the temperature is kept
much more constant and that the space
and the quantity of water required are
less than with tank installations. An
additional advantage in the use of radi-
ators is that they can be used for heat-
ing the office in cold weatiier, being boxed
off in the summer. Fig. 3 illustrates one
method that has been used for shutting
the radiators out from tiic office in hot
weather and shutting them in to heat the
office in cold weather. On the outside
of the wall A, an iron door C is hung
to run on wheels. This shuts in the
radiators in cold weather. A similar
door D, on the inside of the wall, is

•B

a drafty method of securing efficient
ventilation. The air supply should be
taken through a filtering screen to keep
out dust and other abrasive matter.

Thick cast-iron pipes are to be pre-
ferred to wrought-iron exhaust piping
because they can better withstand the
corrosive action of the exhaust gases.
The outlet from the exhaust box or pipe
should never be in proximity to a zinc
roof, as zinc is particularly liable to
corrosion by the gases. Exhaust pipes
should be so set that water cannot col-
lect in bends but care must be taken
that any water which may get carried
along, with the gases does not get blown
into roof gutters or rain pipes as it
would quickly corrode these. It should
be needless to mention the necessity of
insulating the exhaust pipe with asbestos
sheet, or some other fireproof material,
from any brick, masonry or wooden

Fic. 3. Arrangement for Shutting Radiators Either Indoors or Out

hung on wheels E running on the rail F
and is made of two pieces of wood G G,
with a sheet of asbestos H, between
them. This door is closed in summer,
shutting out the radiators, and opened in
winter.

Air and Exhaust Pipes — The air supply
should be taken in all cases from out-
side the building, through a filter. There
is an authenticated case of r. large sta-
tionary gas engine which was situated
in a building, all the windows of which
were shut, and was being started up for
the first time. The "turning over" was
effected by compressed air and great
was the surprise of the beholders when
two of the windows fell in with a crash.
The air supply had been taken from in-
side the building and the sudden reduc-
tion of pressure had proved too much
for the windows. While it is not sug-
gested that an oil engine of ordinary
5ize would cause such damage, it is an
undoubted fact that most cases of rattling
engine-room windows are traced to the
indoor air-supply system. The advan-
tages offered are, of course, the dis-
"placement of the contaminated air in
the building by fresh air, but at best it is

structures through which it may pass.
Many disastrous fires have been caused
by failure to observe this precaution.

Gas Engine Ignition Equip-
ment

By James H. Beattie

A very large proportion of so called
engine troubles are due to faults and de-
rangements of the ignition system. This
assertion has been proved over and over
again by various engine men and is not
questioned by those who are experienced.
It is rather humiliating for an engineer
who takes a pride in keeping his plant
in the very best condition to have a
shutdown due to a broken wire or a
short-circuited igniter plug. An engine
is no more reliable than its ignition sys-
ten: and it is very strange that manufac-
turers put engines out, leaving the most
important of all auxiliary equipment to
the discretion of the purchaser — who fre-
quently has none. It would seem, in view
of the fact that reliable ignition is the
greatest factor in satisfactory operation.

that the ignition system would be the
object of the most scrupulous care on
the part of the engine builder. Never-
theless, one finds engines, upon which
the manufacturers have bestowed every
care and inspected time and time again
to be sure that no defective material en-
ters into their construction, sent out on
the market provided, each, with a set
of six dry cells costing SI. 50 and a few
feet of rubber-covered wire costing 40 or
50 cents.

It has always seemed to me that
the ignition system should be a part
of the engine itself, not a distinct attach-
ment. That is, it should be installed on
the engine at the factory when the en-
gine is built. Ignition dynamos and mag-
netos, in many cases, have been con-
demned when the fault lay not with the
dynamo or magneto but with the way it
was installed. In the first place, prac-
tical engine men have found that mag-
netos should in every case be positively
driven by gears and not be dependent
on friction drives, which are easily af-
fected by atmospheric conditions, oil, etc.
A little thought will make it apparent why
the friction drive cannot be equal to a
positive drive such as is furnished by a
train of gears. On many engines it is
difficult to keep oil off the flywheels and
a very little oil will destroy the useful-
ness of a friction-driven magneto or
dynamo. Under certain atmospheric con-
ditions moisture will collect on the faces
of the flywheels, impairing or practically
eliminating the friction and making the
magneto useless.

Automobile manufacturers have set a
good example that manufacturers of sta-
tionary engines could well follow. They
make the magneto an integral part of
the engine, connecting it to the engine
shaft by gears so that when the engine
starts the magneto starts also. These
magnetos are designed to produce cur-
rent at low speed and are usually strong
enough for starting the engine. Some
makers of magnetos for large stationary
engines provide machines that are actu-
ated by a cam giving an oscillating move-
ment to the armature. Such a magneto
generates a strong current with which it
is possible to start a good-sized engine
without the aid of batteries.

The magneto should, whenever pos-
sible, be located as near the spark plug
as possible, to avoid using any more wire
than necessary. All wiring should be
inclosed- in conduits of oil- and moisture-
proof construction. Engines fitted with
ignition equipment of this sort have been
operated for months without a single
shutdown, save for normal causes. I
have found that for make-and-break
igniters the steel-wound cable used for
carrying current in places where it is
exposed to rough usage gives excellent
results as ignition wire. It is not liable
to be bent or broken easily — in fact, it is
practically indestructible.

August 8, 1911

POWER

211

When several large multicylinder en-
gines are installed in one plant it has
been found best to use current from one
separate dynamo rather than from in-
dividual magnetos on the engines. In
such cases all wiring should be protected
in conduits that will positively prevent
oil and moisture from reaching the wire
and which will, to a large degree, pre-
vent mechanical injury to the wires. It
is often feasible to use current from the
lighting or power switchboard and in this
case it is necessary to connect dead re-
sistance between the igniters and the
switchboard. Incandescent lamps are
frequently used for this purpose and are
connected so that they light only when
the electrodes come in contact, thereby
showing at a glance whether the igniters
are working or not. Two engines in a
small plant in which the ignition cur-
rent is supplied in this way have been
running night and day for six years, with
very little attention. This goes to prove
that where a reliable source of ignition
current is supplied reliability may be had
from engines under adverse conditions.

Crude Petroleum
Bv Frank P. Peterson

.A recent editorial in Po-aer on "The
Oil Engine" suggests some remarks
V. hich may be of general interest. The
statement in that editorial to the effect
inat no field of prophecy has ever proved

'c happily disappointing than that of

roleum is undoubtedly justified by the
facts. Ev'ery year since the first profit-
able finds of oil were tapped, we have
seen the beginning of the end. Those
of us who have seen but little of oil
operations have paid, as a rule, but lit-
tle attention to statistics. We were,
therefore, ready to accept as conclusive
any seemingly authoritative statements
predicting the end of production of crude
oil in the near future.

However, let us look at some statistics
on our own account. In 18.S9 the pro-
duction of crude oil in the United States
was two thousand 42-gallon barrels. In
1874, 10,927,000 barrels were produced
and in 1875 the production receded to
8.789,000 barrels. Had the statistics
then been studied, they would, no doubt,
have seemed much more discouraging
as to the probable life of the industry
than they now appear.

In 1903 our production reached 100,-
463,000 barrels and the years since that
date have shown a remarkably rapid in-
crease of production. There is one re-
cession only, for the year of 1906, when
the production dropped from 1,34,7 1 7.f)00
to 126.494.000 barrels. In 1907 there
was an increase of 31 per cent, over the
preceding year and 1910 showed nearly
19 per cent, over 1909.

World production has, in a measure,
followed that of the United Slates, show-

ing a healthy and almost continuous ad-
vance, with one recession in 1906, due,
no doubt, to our own heavy recession
for that year. Galicia, Japan, Germany
and Peru show recessions for 1910 as
against 1909, but the total world pro-
duction shows an advance for 1910 over
1909 of 11 per cent. The world pro-
duction for 1903 was 194,910,643 bar-
rels and for 1910 it was 335,388,368
barrels.

Reduced to a power equivalent in a
good Diesel engine, consider the value
of this oil. At 6 pounds per gallon and
19,000 heat units per pound, each bar-
rel of 42 gallons should produce 600
horsepower-hours and the power equiva-
lent of the 1910 world production would
make a string of figures too long to read
with any degree of comfort — over two
hundred billion — the equivalent of 22,-
970,000 horsepower 24 hours a day
every day in the year.

But little need be said of the advan-
tages of oil as fuel for power; they are
pretty well recognized, and the perfec-
tion of motors that can utilize it with a
great degree of satisfaction only tends
to hurry the industry to a point which
will encourage the much needed econ-
omy in the production of petroleum that
has never yet been practised to the ex-
tent that it should be.

And from a consideration of the crude
and its possibilities in the field of power
generation we must not pass without
noticing the refined gasolene products.
The modern development of the light-
weight, high-speed gasolene motor has
caused such an increase in the demand
for this portion of the crude oil that not
much of it is likely to be consumed in the
heavier lines of power development. In-
deed the farmer and the blacksmith may
soon have to turn to the cheaper crude
residue which, after being stripped of
its gasolene, is quite satisfactory in an
engine of the Diesel type.

LETTERS

Producer Capacity When
Operating on Lignite

In a recent number of Power an in-
quirer asked how much power a No. 7
Wood gas producer should supply in
gas made from Texas lignite; the answer
was that with lignite of 8000 B.t.u. it
would supply an engine of 300 horse-
power. It seems to me that this is much
too high, because I know of an installa-
tion where a No. 7 producer fell so far
short of supplying a ,300- horsepower
vertical single-acting engine that a No.
8 producer was added. No test has been
made since the second producer was in-
stalled, so I do not know whether both
of them have to be worked at full capa-
city to supply the engine or not. But
I think it impractical to take care of a

300-horsepower engine with one No. 7
Wood producer using Texas lignite.

Georce a. Blucher.
Corpus Christi, Tex.

There are lignites and lignites. Upon
investigating the case cited by Mr.
Blucher we learned that the lignite used
in the plant to which he refers was much
below the average quality, judged by
gas-producer requirements. It is quite
obvious that with lignite containing, say,
6000 heat units per pound, a producer
will not supply as large an engine as
with lignite of higher heat value, but
the grade used in the plant mentioned
must have been worse than any we know
of, in order to make it necessary to run
a No. 7 and a No. 8 producer for a
300-horsepower engine.

The figures given in our answer, we
learn, were a little too favorable. With
ordinary Texas lignite of about 7500
B.t.u. per pound, the No. 7 producer
should supply gas enough to run a 250-
horsepower engine of good efficiency at
rated load, provided the ash is not such
as to cause abnormal clinkering. —
Editor.

I'nu.sual Packing Ring
Reinforcement

A three-cylinder vertical producer-gas
engine had been giving considerable
trouble, passing oil by the rings of two
pistons and depositing carbon in the
cylinders. The cylinders had become
worn so that the pistons had approxi-
mately 0.04 and 0.065 inch clearance (the
engine is about six years old). I took
out both pistons and cleaned them and
the rings thoroughly. Then I put one
turn of '4-inch round braided fiber pack-
ing in each compression-ring groove of
the one piston and slipped the rings on
over it. For the other one, in addition
to the packing, I got some straight strips
of spring steel j'.>x's inch and long
enough to bring the ends within ' S inch
of meeting when the strip was bent into
the ring groove over the packing; about
4 inches of the ends were bent to form
a circle when the ends were brought
together. I put one strip in each com-
pression-ring groove over the round pack-
ing and held the ends together while I
slipped the rings in place. Both pistons
were given a liberal dose of graphite
and oil and put into commission. That
was three months ago and we have not
found a spoonful of carbon in either cyl-
inder since and the pistons do not slap
as before. The engine runs 16 hours
a day except Sundays. ' venlually both
cylinders will have to be renorcd and new
pistons fitted, but we could not arrange
to do that now, therefore this experi-
ment.

i. W. Fries.

Middleboro, Mass.

212

POWER

August 8. 1911

The Reniek Transformer

The general design and construction
of transformers for ordinary service were
reduced to a basis of standard uniform-
ity several years ago, but there are al-
ways details to which the ingenuity and
skill of the designer may be profitably
applied. The Remek transformer built
by the Crocker-Wheeler Company is an
excellent illustration of the truth of this
assertion. It is of the well known shell ting edges of the yoke plates. This
type, in which the windings are arranged expedient is said to be so successful
in a single group surrounding the main that the insulating compound which is
core of the magnetic circuit and being forced into all openings of the complete

Dim

Figs. I, 2 and 3. Re.mek Transformer Core Plates

surrounded by the "return" or yoke
structure. In that respect it is precise-
ly like all other shell-type transformers,
but there are several detail features of
interest.

A yoke plate and the corresponding

transformer under a pressure of 60
pounds per square inch does not pene-
trate into the joints between the core
and the yoke. Fig. 1 shows a yoke plate,
Fig. 2 a core plate and Fig. 3 the two
together in "working" position.

Figs. 4, 5, (i and 7. Remek Transformer Parts

core plate are punched from sheet steel The core plates are assembled under

by one stroke of the press, in order to pressure and held together by clamps

make sure of an accurate joint between which do not surround the core and

the ends of the core plates and the abut- therefore do not form closed secondary

circuits for the flow of induced currents.
This construction is illustrated by Fig.
4. The yoke plates are assembled over
the ends of the completed core, then
subjected to pressure and held together
by clamps which do not surround the
magnetic circuit; Fig. 5 shows an as-
sembled yoke without the core and il-
lustrates how these retaining clamps are
disposed.

Fig. 6 shows a complete group of coils
standing on end in the position which
it occupies on the core and in Fig. 7
may be seen the heavy insulating sheets
between the outer surfaces of the wind-
ing and the inner faces of the yoke;
also the supplementary' clamps at the
top and bottom of the structure for hold-
ing the core in place in the yoke. At
both ends of the windings the coils are
spread apart to permit circulation of oil
between the sections; these end por-
tions project beyond the mass of the

Fig. 8. Complete Windings

yoke, as shown in Fig. 7. Fig. 8 illus-
trates the spreading of the coils to pro-
vide oil ducts. In this particular case
the low-tension winding was made up
of copper "ribbon." This was wound
on the forming bobbin first and the high-
tension coils were wound on top of it,
suitable insulation being applied to the
outside of the first winding, of course,
before the outer one was started.

The core and yoke are made up of
silicon steel which is said to be free
from "ageing" and the absence of lap
joints in the magnetic circuits is claimed
to prevent eddy currents in the steel.

August 8, 1911

POWER

213

The insulation is also claimed to be
unusually efficacious and durable. After
the coils are wound and put in place,
they are cleared of tnoisture and air by
the usual vacuum process; then the
crevices are all filled and the surfaces
covered by a compound which is in-
soluble in oil or water, the compound be-
ing applied at 60 pounds pressure per
square inch.

The Electrical Section of the
Bureau of Mines

The United States Bureau of Mines,
which is doing such valuable work in the
investigation of methods and apparatus
for the utilization of fuels, is also doing
excellent work in the way of investigat-
ing electrical apparatus used in mining
and the conditions and manner of use. A
distinct Electrical Section of the bureau
was organized about two years ago to
make these investigations and to col-
lect data which would be of assistance
to those State officials who have charge
of the regulation and inspection of mines
and to all who use or manufacture elec-
trical mining equipment. The section is
part of the mining-experiment station of
the bureau at Pittsburg, Penn.

Among the purposes of the section are
the ascertainment of the causes of ac-
cidents from the use of electricity in
mines and the suggestion of means for
the prevention of such accidents; making
tests of the safety of electrical equip-
ment under conditions most conducive
to disaster, and making such tests of a
general nature as bear upon the safety
of electricity in mines, accidents at-
tributed to electrical causes, etc.

Electricity is used underground in
/nines for haulage, lighting, driving
pumps, fans, drills, coal-cutting ma-
chines and hoists, for detonating explo-
sives and for signaling.

Both direct current and alternating cur-
rent are used, the former much more
extensively than the latter. Direct cur-
rent is distributed at potentials up to
600 volts wherever power is used. Al-
ternating current is distributed at over
2000 volts and is usually carried only a
short distance underground to serve high-
voltage motors or transformers operating
motor-generator sets or rotary converters.

Electric haulage is operated principally
from trolley wires at 250 or .500 volts.
The trolley wire is necessarily bare, and
in low coal is dangerously near the heads
of persons in the same entry with it.
Lighting circuits are often connected be-
tween the trolley wire and earth, with
the lamps in series. Stationary motors
are often connected between the trolley
wire and earth. Machine wires arc fre-
quently bare up to the point of connec-
tion with the trailing cables.

Explosives are detonated from bat-
teries (storage or primary), from mag-
neto generators (frequently referred to

as batteries), from power circuits and
from separate generators used only for
detonating. Signals, which include lights,
bells and telephones, are operated prin-
cipally from primary batteries.

Conditions of Operation

Underground equipment is exposed to
falls of roof, coal and rock that are suffi-
cient to wreck installations of the best
character. The acid waters and the
dampness in mines make the insulation
problem difficult.

The fact that the need of electric ser-
vice at many points underground is only
temporary, limits economical investment
in equipment. The temptation to install
electrical equipment in coal mines in a
temporary and improper manner is in-
creased by the fact that coal, especially
dry coal, is not a good conductor of elec-
tricity, and wires may sometimes come
in contact with the coal without caus-
ing trouble. A machine wire supported
upon wooden pegs driven into the coal
may never give trouble, and it would
be hard to convince a man whose only
experience had been with such installa-
tions that to thus support a wire is not
good practice.

In this connection it is probable that
electrical practice in mines would be
generally improved if more of the mine
electricians were familiar with the best
installation methods.

The problem of safeguarding life is
rendered still more difficult by the fact
that many of the underground workers
do not appreciate the dangerous char-
acter of electricity and ignore the rules
made for their protection.

The three principal dangers connected
with the use of electrical equipment in
mines are the danger from electric shock,
the danger from explosions caused by
electricity and the danger from fire
started by electricity.

The chief sources of danger from shock
are the trolley wire and other bare con-
ductors. Another source is ungrounded
equipment that has become charged with
electricity through defective insulation or
otherwise.

The danger from electrical explosions
arises from the occurrence of sparks and
arcs in inflammable gas or dust. Sparks
of sufficient size to ignite gas may be
produced when a motor is started rapidly
or operated under heavy load, when a
circuit carrying current is opened or when
a circuit becomes grounded. A much
larger spark is required to ignite bitumi-
nous coal dust, but such dust might
be ignited by the opening of a circuit
carrying a large current or by flashes pro-
duced by heavy short-circuits. The fall
of a trolley wire might produce both of
these conditions.

The danger from fire arises from
grounds to coal or in the vicinity of in-
flammable material, from the flashing of
motors under the latter condition, from

short-circuits and the burning off of wires
carrying heavy currents.

Besides the above mentioned dangers,
the handling of explosives in the vicinity
of electricity and the detonation of them
by electric means give rise to others.

Safeguarding the Use of Electricity

The practical solution of the problem
of safeguarding the use of electricity in
mines will require the adoption of pro-
tective measures and of devices that are
simple, rugged, "fool proof" and as in-
expensive as possible. At the same time,
both measures and devices must be en-
tirely effective or they will become
menaces.

Although it will be necessary to in-
vestigate many possible causes of elec-
trical dangers, some are already well
known, and the desirability of protection
against them is apparent.

There is a field for devices for reduc-
ing the danger of shock from the trolley
wire and for devices for preventing the
ignition of gas by motors, switches and
other circuit-opening aparatus. There is
a field for an acid-proof material for in-
sulating wires and cables and there is
room for improvement in the methods
of installing electrical equipment under-
ground.

Equipment of the Electrical Section

Direct current is available for^ testing
purposes in any voltage up to 750 volts,
and alternating current up to 2000 volts
for power and up to 30,000 volts for
high-potential tests.

The laboratory is provided with a (5-
panel switchboard for the control of
transformers, generators and circuits; a
complete equipment of alternating-cur-
rent aiid direct-current voltmeters and
ammeters; an outfit for measuring insu-
lation resistance up to 80,000 megohms;
a 5-kilowatt high-potential testing trans-
former, the voltage of which can be
gradually varied up to 30,000 volts; a
Wheatstonc bridge, rheostats and mis-
cellaneous tools and supplies.

There are two galleries for testing
electrical equipment in the presence of
gas. The smaller of these is installed
in the laboratory; it consists of a boiler-
iron box provided with connections for
gas and air, heavy plate-glass observa-
tion windows and openings' for relieving
the pressure caused by an explosion. A
small motor-driven centrifugal fan is
used to mix the gas and air and to cir-
culate them through the gallery. Means
are provided for prcdctemiining the per-
centage of gas in the mixtures used.
Tests of electric sparks and nf incan-
descent lamps and small apparatus are
made in this gallery.

The larger testing gallery is a tube
designed to represent a short section of
a mine entry. It is erected outside the
laboraiorv and consists of a cylindrical
shell of boiler iron 30 feet long and 10

214

POWER

August 8, 1911

feet in diameter, laid horizontally upon
a concrete bed and partly filled with
concrete to form a floor upon which ap-
par^-ius can be set up for test. At IVj
feet from either end the cylinder can be
stopped off with diaphragms of heavy
paper, which relieve the pressure from
explosions before it becomes dangerous-
ly heavy. After the diaphragms are in
place the gallery can be entered through
a manhole cut in the side of the shell
between the heads. Heavy glass win-
dows are set in the sides of the gallery.

A large motor-driven centrifugal fan
mixes and circulates the gas and air and
a special device has been developed to
indicate the percentage of gas in the
mixtures. Tests of explosion-proof
motors, explosion-proof switches and
other large apparatus are made in this
gallery.

A gallery or testing tube for investi-
gating the ignition of coal dust by elec-
tricity is now being designed and will

Fig. 1. Mr. Malcolm's Method

be constructed shortly. This gallery will
be similar in most respects to those
already described, but will differ in a
few details.

The electrical section of the bureau
has made a few preliminary investiga-
tions, the most important of which are
an investigation as to the danger of gas
ignition by the indicators of inclosed
fuse'^, and an investigation as to the
danger of gas ignition by incandescent
lamps when broken in gaseous atmos-
pheres. The former is reported in de-
tail in a pamphlet designated Technical
Paper No. 4, by H. H. Clark, to vchich
we are indebted for the foregoing in-
formation; the latter is being continued,
and a final report will be made later.

Although the function of the section
is to investigate and test rather than to
develop, facts that will be of value to
those designing equipment are continual-
ly being learned in the process of test-
ing and are always at the disposal of
interested persons.

CORRESPONDENCE

Two Phase Three Phase
Transformer Connec-
tions

Referring to the transformer connec-
tions proposed in the July 4 number by
S. H. Harvey for connecting a two-phase
and a three-phase circuit, permit me to
point out that his method would entail a
serious flow of wattless currents and
an overlapping of the two-phase cur-
rents which would cause bad regulation
and necessitate the use of larger trans-
formers than would otherwise be re-
quired. A much better method would
he to connect the windings up Y-fashion,
as indicated by Fig. 1 herewith. This
diagram shows only one set of trans-
former windings; the other set would be
connected to the three-phase circuit in
the usual way.

Phase

the T-connection originated by Charles
F. Scott is by far the best method.

George W. Malcolm.
Brooklyn, N. Y.

Fig. 2. S. H. Harvey's Method

This arrangement has the slight dis-
advantage of not utilizing all of the
windings A and C, but that is better than
to have useless currents circulating in
them and overlapping the currents of
the two phases. Phase I is supplied
exclusively by the transformer B and
Phase II by the transformers A and C
in series. In Mr. Harvey's proposed
arrangement, shown in Fig. 2, Phase I
is supplied by the transformer C partly
opposed by the short ends of A and B,
and by the long- ends of A and B in
series; Phase II is supplied conglomer-
ately by all three windings, of which C,
however, acts differentially. Therefore
the currents of the two phases are
superimposed in the windings and pro-
duced by complex resultant electromo-
tive forces the unbalancing of which
must set up wattless local currents. The
arrangement in Fig. 1 Is free from these
disadvantages.

When all is said and done, however,

The use of three similar transformers
for connecting three-phase and two-
phase circuits as described by S. H.
Harvey in the July 4 number is open
to the disadvantages that there is heavier
wattless current flow and the regulation
is poorer than with the Scott connection.
The excessive wattless current neces-
sitates the use of larger transformers;
the cost, therefore, will be greater.

A. L. Harvey.

Pittsburg, Penn.

Cuttinjr Out D^'namos from
Parallel Service

In the issue of June 27, on the page
of "Inquiries of General Interest," a
correspondent signing himself "W. H.
L." asks for an explanation of bad speed
regulation of one of two engines driving
dynamos in parallel. The correspondent
states that when transferring the load
from the large to the small generator
the voltage drops momentarily from 125
to about 75 or 80 volts, and your state-
ment that the cause of this trouble is a
sticky governor on the small engine is
undoubtedly correct.

It may be of interest to this and other
readers to point out that it is not a good
plan to throw a considerable load on a
machine all at once. The large machine
in the case cited was stated to be twice
the size of the small one; therefore, if
both were carrying the same proportional
load just before the large generator was
cut out, the small one must have had
its load suddenly increased from one-
third to full load. With many generators,
especially of the older types, this will
cause sparking at the brushes and may
require that they be shifted. A safer
way would be to slowly weaken the
field of the large generator, at the same
time strengthening that of the small one
so that the voltagt would remain un-
changed. This will require a few moments
more for making the change but that
would be unimportant and would pre-
vent any drop in voltage even If the
governor of the engine did not act quick-
ly enough and at the same time would
prevent any trouble from sparking.

I do not mean that the governor should
not be attended to at once, but merely
that if the generator were carefully cut
out there would be no drop In voltage
even if the engine were not governing
correctly. The proper plan Is, of course,
to have all machinen.- in as perfect con-
dition as possible so that it will act prop-
erly under all conditions, but those condi-
tions should not be made any more
severe than necessary.

G. H. McKelw.\.y.

Brooklvn. N. Y.

_ L

AuRust 8. 1911

P O W" F. R

Receiver Presssure Spring
Rods

Some few years ago in a power plant
a new cross-compound engine, 30 and 60
by 48 inches, running at 80 revolutions
per minute with 140 pounds steam pres-
sure was operated for some months non-
condensing.

The engine ran smoothly at first, but
after the condenser was connected it
pounded badly, because of the position
of the exhaust eccentric.

At this stage an experiment was tried
with the receiver pressure to reduce the
pounding in the low-pressure cylinder.
The receiver pressure was started from
18 pounds downward and the pounding
seemed to grow less with each change,
but it would return a few moments later
to its usual loudness. Finally getting
the pressure down to about 7 pounds
and while waiting to see if it was sta-
tionary, the assistant shouted that some-
thing was wrong.

The low-pressure piston rod, 6 inches
in diameter, was riding on the rod-pack-
ing case and smoking. I hurried to the
governor and raised the receiver pres-
sure, whereupon the rod came back into
its central position and ran all right
for the remainder of the day.

The matter was reported to my su-
periors, but as no satisfactory solution
was given it was finallv dropped. To
my mind the low receiver pressure vas
the cause of the trouble.

A second instance occurred about a
year later on a cross-compound 16 and
32 by 42-inch engine running at 120
revolutions per minute with 120 pounds
steam pressure. The low-pressure pis-
ton rod was 4'j inches in diameter.
Just after one o'clock the load started
to come on. This engine had not teen
running over 10 minutes when the as-
sistant called to me to hurry to the
low-pressure side as something was
wrong.

The rod was riding on the packing case
and smoking as in the first instance, and
Tders were given to shut down. After

• le load was off and before the engine
Aas stopped the rod came up clear and
central. While the engine was cut in,
the receiver pressure was about 2
rounds, whereas from 6 to 8 pounds was

:^ually carried.
I he attention of the chief engineer
as called to the fact that the piston

• 'd had raised clear off the packing case
fter the steam had been shut off, and

■'iht the receiver pressure was low at the

time of the trouble. As he had been
previously told about the first instance
he was persuaded to try the engine again
with the normal receiver pressure. Every-
thing was found to be all right and the
engine ran the rest- of the day.

But what made the rod spring down
so that in both cases it rode on the pack-
ing case and scored it?

Almost any engine can be loaded
heavily enough to bring it to a dead
stop without springing of the rods, but
in these instances no reduction of speed
was noticeable.

In many engines the low-pressure pis-
ton rod is larger than the high-pressure,
although it is usual for it to carry no
more load than the high-pressure, and
any springing would show that consider-
able resistance was being exerted.

L. M. Glodell.

New Haven. Conn.

Smoke Preventer

How to avoid smoke coming out of
the chimney is one of the troubles of
some engineers. Quite a few fines have
been paid because of violation of the

Fig. 1. Elevation op Furnace and

Sti>am Jet

smoke nuisance and recently one com-
pany was fined S2400.

The accompanying illustrations show a
form of smoke consumer that I am using
with excellent results. There are four

2-inch pipes. Fig. 1. 11 inches long,
extending through the boiler front to the
inner side of the brickwork. Inside of
each is a '4-inch pipe which extends
three-fourths through the 2-inch pipe.
Each is fitted with a cap having three
1 16-inch holes which act as steam jets
and draw in the air for a period of two
minutes after each firing. The jet is then
shut off by means of the valve shown at
the right. There are also covers which
drop down by turning the crank at the
left after the jet has been shut off to

F^rforattd Brick

^Pf5

Fig. 2. Plan of Furnace

prevent cold air from drawing in over
the fire.

Fig. 2 shows the bridgewall of the
boiler. It has a row of perforated brick
on top that are set over a hollow sec-
tion and air ducts are provided under
the grates, causing air to mix with the
combustible gases. Although this method
has a tendency to cool down the furnace
temperature and increase the coal bill,
it almost entirely prevents the formation
of smoke. With a coal consumption of
12 tons per day, under three 200-horse-
power boilers, one can scarcely tell when
the furnaces have been coaled.

A. C. Waldron.

Revere, Alass.

Clo{jged Condenser Gage Pipe

In the plant where I was engineer a
few years ago there was an independent
air pump and jet condenser used to con-
dense the exhaust steam from a tandem-
compound engine. On starting up one
morning, after several days' shutdown,
the vacuum gage showed but 16 inches
of vacuum. There was about a 20-foot
lift of the injection water, and as the
pump was running normally and the con-
denser was cool, it showed that it was
getting all the water necessary to con-
dense the exhaust steam.

It was evident that the trouble was not
in the pump or in the condenser.

I disconnected the union near the vac-

216

POWER

August 8, 1911

uum gage and when I put my finger on
the end of the pipe I knew I had dis-
covered the trouble; there was no suc-
tion to speak of in the ;4-inch brass gage
pipe. 1 removed the pipe and found that
two cast-iron elbows, which were under
the floor, had been substituted for brass
ones. The cast-iron elbows were plugged
almost solid with iron rust. After put-
ting in new brass elbows the gage showed
26 inches of vacuum, and no further
trouble was experienced.

A. Lamarine.
New Bedford, Mass.

Lifting Water in Boilers

I believe that the average boiler ex-
plosion, caused by cutting in a boiler
when the pressure is above the line pres-
sure, is due to the rapid evaporation of
the water and not water hammer.

A boiler on the line has its water in
circulation and only a part of the water
is at oi' very near the right temperature
to flash into steam.

A burst steam pipe would suddenly
lower the pressure and cause more water
to flash into steam, but the circulation
would not be upset for some time.

As the temperature ranges from the
flashing point at the pressure carried
down to the temperature of the enter-
ing feed water, all the water could not
flash into steam at once, but would pro-
duce water hammer if it did not follow
in the path of the downward circula-
tion.

When a boiler is being fired prior to
cutting in on the line, the fires have
been burning more or less slowly, the
water circulation is practically dead and
the temperature of the water has been
raised against a steady, increasing pres-
sure.

The greater portion of the water in the
boiler is at the same temperature and
just about at the flashing point.

Now open the stop valve suddenly to
a lower pressure. All the water which is at
the temperature range between the origi-
nal pressure and that to which the pres-
sure falls will flush into steam.

Because there is no circulation in the
boiler, the rise of steam bubbles will
cause the water to lift and relieve the
water in the lower parts of its weight and
release more steam.

The pressure and temperature rise
quickly and the boiler shell, not having
time to adjust itself to the new condi-
tion, lets go.

If the water lifted were projected against
the head or allowed to fall back as solid
water, it would wreck the boiler, but the
density is so reduced by the steam bub-
bles that with the exception of very
long vertical boilers, the shock of the
striking water would not wreck the boiler
if it stood the sudden rise in pressure.

By opening the stop valve to a cold
boiler or one under a pressure very

much below the line pressure a bad water
hammer might be started that could
wreck the boiler.

I think that flattening out of sheets
and the distorted appearance of an ex-
ploded boiler is due to the reaction or
kick of suddenly fractured metal, the
same as a broken chain or wire rope. I
cannot see how water-hammer action
similar to that taking place in a header
or pipe can occur in a boiler with a
higher pressure.

In the case of a bad pipe water ham-
mer there is a solid plug of water with
a vacuum before it and a greater or less
distance through which the plug travels,
acting as a pump plunger to a certain
extent.

Evaporators such as are used on board
ship, when connected direct to the main
condensers, will foam badly if the dis-
charge valve is not kept partly closed.
All the water appears to be at the top.

I have never been able to detect any
shock when the foaming was stopped
either by shutting off the live steam or
choking the discharge valve. I do not
mean that water lifting does not take
place or that it is not dangerous to a
certain extent, but I believe that the
danger is more from the shifting of
weight than by the impact of water
against the head or bottom.

In cutting a boiler in on the line, I
always free the boiler of air and shortly
before the pressure is the same as on the
line, the feed valve is opened part way
and kept open. This starts the water to
circulating and the boiler is in condition
to go to work.

C. J. Harden.

Chicago, 111.

Running a Pump with Broken'

Cylinder Head

One night at about 1 o'clock, a small
pump gave out and I found that a
jam nut of one of the pistons had worked

and a piece of board over the packing.
A jack screw was placed against a coal
bunker and tightened up, which stopped
the leak sufficiently to permit the pump
to run until another cylinder head was
obtained.

John D. Meyer.
New York City.

Repaired Engine Frame

The illustration shows a repair job
that was successful. The fracture was
in a guide column under the intermediate
cylinder of a triple-expansion engine. The
crack extended around the back and
two sides. Holes were made in the
frame by drilling a lJ4-inch hole and

-<r^'' ri

Clamp Applied to Cracked Frame

two 5, s -inch holes below, and then
chipped to the shape shown at A with
a cold chisel. The clamps were made of
i;4x2-inch bar steel, in the shape shown
at B. The short clamps were about 8
inches long, and the longer ones were
15 inches. The clamps were put into the

Method of Holding Cylinder Head in Place

loose and knocked a section out of the
cylinder head.

I tightened up the jam nut and re-
placed the broken head, putting a piece
of sheet packing over the broken place

boiler furnaces and placed in the holes
red hot and the contraction closed the
crack.

W. E. Dean.
Superior, Wis.

August 8, 191:

POWER

217

Oiling Kinks

When oiling machinery of any kind,
especially an engine, it is annoying to
stick the spout of an oil can into the
oil hole and have it caught because it
was run in too far. By soldering a piece
of tin or other metal or even running

Fig. 1. Showing Ring of Solder on
Spout

a heavy ring of solder around the spout
of the oil can a desired distance from
the end of the spout, as shown in Fig. 1,
the end of the spout will be prevented
from entering the hole too far.

Another annoying thing about oiling
is the manner in which the oil is ap-
plied to the wristplate bracket pin, on
close-coupled high-speed and even on
medium-speed Corliss engines. This pin
is very hard to oil. and the oiling must

Fir,. 2. Showing Oil Wiper Attached

either be intermittent, as the oiler hap-
pens to think, and squirts oil on. or a
glass or other kind of oil cup is fastened
directly to the wristplate, which arrange-
ment does not give good oil regulation.
I have made a change that permits
fine oil regulation by screwing a wiper
into the hole where the oil cup was.
Then two holes were drilled In the lag-

ging of the cylinder and tapped out for
small cap screws which held a piece of
',s-inch iron, bent to the suitable angle.
The oil cup was fastened to the iron
arm and as the wiper moved back and
forth it received sufficient oil to lubri-
cate the wristplate bearing.

R. S. WiLHELM.

Indianapolis. Ind.

Preventing Steam Turbines
from Racing

In a certain steam plant there are three
1500- and one 750-kilowatt Parsons tur-
bines. These turbines were inclined to
run greatly in excess of their normal
speed when operating under little or no
load, due partly to the lack of lubrica-
tion and partly to the admission of too
much steam beneath the steam piston
of the primary valve.

Originally the oil was admitted through

Fir.. I.

SECriON THROUGH CONTROLLING

Valve

a !-S-inch pipe connection A, Fig. 1, and
was exhausted with the steam which
leaked around the piston to the at-
mosphere by means of a 'l-inch pipe
connection, on the same plane as the
lubricator connection, but PO degrees
farther around and not shown by the il-
lustration.

After changing, the lubricator was at-
tached to the ' -inch pipe connection on
the tee-shaped fitting C, Fig. 2; and this
fitting was connected where the needle
valve formerly was, or at B. Fig. 1.
After tapping a ^(l-inch hole for the 14-
inch pipe the needle valve £ was length-
ened and extended through this Piling

and made contact with its seat as for-
merly.

The change has, therefore, no effect
on the adjustment of the needle valve.
But as the steam must pass through this
needle valve to operate the piston and
feed the oil into the steam by means of
the tee-shaped fitting, the steam becomes
thoroughly saturated with the oil before
it has reached the piston, thereby in-
suring perfect lubrication.

Referring to Fig. I, it will be seen
that a stem passes through the valve
which extends down into a bronze bush-
ing or guide. In order to relieve the
recess below the end of the valve stem
of any pressure which may be created,

Jam Nut/^-i^' ->||^^U-^£^

Details of Tee Fitting

a hole has been drilled through the cen-
ter of the stem.

This allows the steam which leaks
around this bushing to exhaust into the
cylinder just beneath the piston. After
being in service for some time this bush-
ing becomes worn. The amount of steam
which p^asses around this and is ex-
hausted beneath the piston is so great
that the primary valve is not able to seat,
and with little or no load the turbine
will speed up.

This may be readily overcome by tap-
ping out the hole in the end of the valve
stem and screwing in a plug. Then file
three or four grooves in the bronze bush-
ing which will allow the pressure to
equalize beneath the stem and thus it
will in no way interfere with the proper
working of the valve.

k small hole, about 3 32 inch, may
he drilled in the cap which holds the
bronze bushing in place, which will drain
into the turbine any water which may
collect below the stem. Although this
hole will permit steam to enter the tur-
bine even though the valve be closed,
the amount will be so small that it can
have no effect on the operation of the
turbine.

Bl.'RTl'S ViNNEDGE.

Hamilton, O.

A certain steam pipe vibrated so much
that the engineer found it necessary to
drive wedges between it and the wall. It
was decided that the vibration was in
phase with some of the reciprocating
parts of the engine. To slop it heavy
cast-iron weights were hung beside the
pipe and bolted to it at the flanges by
heavy iron straps. The weights did the
work.

POWER

August 8, 1911

Poor Draft

In the July 4 issue. Mr. Cotton says
he has poor draft. I thiiik the fault is
because the distance between the back
wall and boiler is only 15 inches — it
should be 24 — and between the flue doors
and boilers the distance is 17 inches
which should be 20. ■

I think if Mr. Cotton would place a
y^-inclt steam pipe at the bottom of his
upright stack, putting an ell and a short
piece of pipe so that a small amount of
steam would flow upward, he would get
all the draft he wanted.

Care should be used not to make it
too strong as it will cause the fire to
clinker.

L. B. Scott.

Clarksburg. W. Va.

L. P. Cotton states that he has poor
draft. Ihe size of his stack is as given
in ordinary installations and the smoke
connection is nearly correct, although
16x67 inches would be better. The dis-
tance between the boiler head and rear
wall should be 30 inches instead of 15.
If there are high buildings or trees near
the stack it may be necessary to add to
the hight.

Mr. Cotton should make and install
a draft gage so as to tell how much draft
there is. A gage was described recently
in this paper. If his firm will install a
blower (of which there are many types)
he can get all the steam he needs.
A blower will soon pay for itself in the
fuel saved from being poked into the
ash pan. Any kind of fuel must burn
if the draft is forced.

Roy V. Howard.

Tacoma, Wash.

What Causes tlie Pipe to
Wear

In the June 13 issue of Power, S.
Kirlin wants to knov.- why the top side of
the horizontal discharge pipe through
which water, mud and sand is pumped, is
worn more than the bottom.

Mr. Kirlin will find an answer to his
question, if he will stop to think that in
?ny inixture of different-sized particles,
either solid or part solid and p^rt liquid,
when violently agitated or disturbed, the
tendency is for the larger particles to be
held upward, while the finest particle
will work toward the lowest point. In
a bucket filled with water and a few
handfuls of sand and gravel thrown into
it, when swiftly stirred, the largest par-
ticles will be felt tj^e higliest on the stir,-

Comment,
criticism, suggestions
and debate upon various
articJes.letters and edit-
orials which have ap-
peared in previous
issues

ring stick. Thus the friction of the coarse
particles against the top of the pipe
rapidly wears it away, while the bottom
of the pipe gets practically no friction.
L. M. Johnson.
Glenfield. Penn.

Boiler ■Management

In the June 13 number of Power 1
noticed Mr. McGahey's article, "De-
terioration of Boilers," in which he
speaks of steel becoming brittle from
long use. Is it possible to renew the
life of the metal occasionally by any
known method?

Lately I was talking with an engineer
who recommended that a slow fire be
built under a dry boiler to anneal the
metal and stop its crystallization. The
flues are to be rerolled while the boiler
is warm, and in no instance must the
boiler be heated red hot. Has any reader
ever tried or made a practice of this
method of retreating boilers to give "a
new lease of life"?

The engineer above referred to had
just taken charge of the plant and I
was asking about some blowoff trouble
which had happened a few days before,
whereupon he invited me around to see
the arrangement of this very necessary
fixture.

The naked nipple was screwed into the
boiler and was so very short that the
piece of pipe extending out through the
wall of the furnace was in the hottest
flame. Because of this it became so
"frail" that it gave way under the strain.

The engineer was very anxious for
Sunday to come so that he might put in
a longer nipple, incase it and drop the
extension pipe below the fire line.

It is a sad state of affairs that an en-
gineer, after discovering and having
trouble with a thing of this kind, is com-
pelled to wait until Sunday to correct it,
while every moment of its operation is
practically as dangerous as it would be
to continue it for a greater time.

Who is to blame that the plant owner
is not more informed regarding dangers

existing in his plant, if he is ignorant of
engineering? Should an engineer be
forced to take questionable orders from
the boss who is ignorant along this line?

The plant owner should always be
well informed to appreciate a careful
engineer's findings and recommendations
in the building of a steam or other kind
of plant.

There are a few small plants where
gross ignorance is displayed by both
parties.

This state of affairs, I am glad to see,
is improving every day, and I see no
reason why anyone should be ignorant
of fundamental principles, since the op-
portunity for learning is greater than
ever before.

Lloyd V. Beets.

Nashville. Tenn.

Boiler Design

In the issue of June 27, J. E. Terman
expresses his disbelief in some of the ■
statements made by me in my recent
article on the above subject. Of course, I
expected disagreements, but I shall not
enter into a controversy concerning
them.

If Mr. Terman can enjoy peace of
mind in contemplating a boiler with its
ends tied together by means of a flexible
connection in transverse strain he is
fortunate. The fact that such boilers
have not exploded is not a measure of
their nearness to explosion.

Concerning the saw-tooth butt joint, I
read many years ago, when I was a mem-
ber of the Institution of Mechanical En-
gineers of England, the report to which
Mr. Terman refers. In my opinion it is
far better to make the butt straps of a
boiler narrow and correct the weakness
which Mr. Terman suggests by making
the butt straps thick. It is important
that the inside butt straps, which in gen-
eral are not calked, should be narrow
and thick for reasons that 1 have before
explained.

Concerning a coned plate, many have
been made and have been used in loco-
motive boilers for 75 years in tens of
thousands of cases, and are being made
now, and it is hard to believe that there
is the least difficulty in making them.

Readers may be interested to know .

that the boilers oT the great steamships i

"Olympic" and "Titanic" have butt
straps with the very wide pitches recom-
mended by me before I adopted the saw-
tooth form, and, of course, many of

August 8, 1911

POWER

219

them know that the latter form has been
used by the North German Lloyd line
for 15 years or more.

F. W. Dean.
Boston, Mass.

Mr. Terman criticizes to a certain ex-
tent Mr. Dean's article in the May 16
issue. I heartily agree with Mr. Terman
that the attack on the Manning boiler
is entirely unwarranted. The Dean ver-
tical boiler, while strong and rugged, is
of small capacity compared to the Man-
ning boiler of the same size or of equal
cost, largely owing to the gallery which
is left between the tubes and the shell;
this greatly increases the water space
but very largely reduces the heating sur-
face; therefore, for the same capacity
the diameter of the boiler must be made
very much greater.

Doubtless the reason for the compara-
tively small number of tubes is the fact
that the firebox is of smaller diameter
than the shell, and it is of no avail to
use an amount of heating surface which
is larger than that for which the grate
surface can economically supply heat.
In the Manning boiler the firebox is en-
larged or the diameter of the shell is
decreased. The result is that the thick-
ness of the head and of the shell plates
can be diminished, which will materially
reduce the cost of the boiler for the
same capacity. The "ogee" plate or
flange as a rule gives little or no trouble.

As to increasing the number of tubes
in a horizontal return-tubular boiler, this
would seem entirely unwarranted in most
conditions. In the first place, it greatly
reduces the water space of the boiler,
making it possible to burn out the upper
row of tubes or greatly diminish the
steam space, with the result that water
would likely be carried over with the
steam. Further, the narrow spacing re-
quired makes the circulation bad, and
it is almost impossible to get at and
clean the shells, which even in present
boilers is hard enough. Unless boilers
are built with far more care than is
ordinarily the case the tube sheets are
likely to give more or less trouble.

Boilers larger than 84 inches require
very heavy plates, and offer a splendid
opportunity for burning them at the
joints unless they are built with very
great care. It seems doubtful if, taking
all things into consideration, the increase
of boilers to over 84 inches in diam-
eter is warranted.

On the whole, it seems very curious
for Mr. Dean to advise increasing the
capacity of vertical boilers by increasing
the number of tubes, as the boilers of
the design for which he is responsible
have as a rule far less capacity for the
same space than any other boilers of
equivalent size. I am speaking now of
the boilers which he has designed for
the city of Boston, where he has used
the Scotch type, whose capacity of 116

horsepower is small compared to a hori-
zontal return-tubular boiler that can be
installed in the same space.

Henry D. Jackson.
Boston, Mass.

Value of Flue Gas Analj sis

Having carefully read the article by
Joseph W. Hays in Po>xer for June 6,
entitled "Value of Flue Gas Analysis,"
I feel pleased to say that with few ex-
ceptions Mr. Hays' views on the matter
come nearer to the solution of the fuel-
wasting problem than any of the boiler
and furnace equipments which have been
introduced and installed for fuel-econ-
omy purposes.

It is certainly true that tne average
fireman is somewhat lame when the sub-
ject of furnace chemistry is suggested,
not alone in the lack of education on
the matter but largely from the fact
that he does not consider such knowledge
necessary, for the reason that fuel used
in the boiler room was not taken into
account as a very costly item. While it
requires very little study for the fire-
man to become familiar with the chim-
istry of fuel or gas combustion in a
steam-boiler furnace, it takes years of
repeated efforts to become familiar with
the practical requirements.

If chief engineers would not be so
narrow-minded and would impart the
necessary knowledge to the firemen and
others in their charge, their work would
be more pleasant and the plant as a
whole would at all times develop the
highest possible efficiency. It is a sad
commentary on the organization of a
power plant when persons therein are
not familiar with all of the essential
features; and a sad reflection on the ef-
fort of the chief when he says that his
fireman would not learn the laws govern-
ing the chemistry of a furnace or un-
derstand a CO; recorder in a thousand
years; this is simply rot.

Statistics show that the best engi-
neers are men who are practically
trained in the boiler room, and men of
this class never boast that their coal
consumption averages about 3 pounds
per kilowatt or that they get an evapora-
tion of from 10 to II pounds of water
per pound of coal, because they know
that such results cannot be accomplished
by any grade of coal on the market. If
more attention were given to the employ-
ment of good firemen, who could be in-
structed as to when their fires should
be coaled and cleaned; how to regulate
properly the air supply so as to guard
against serious changes in furnace tem-
perature; and how to avoid as much as
possible surplus boiler capacity, they
would then show a far greater saving in
fuel than can be done by installing pres-
sure-reducing valves. CO. recorders,
draft-pressure gages, automatic damper
regulators and unnecessary steam traps.

Mr. Hays no doubt is aware of the
fact that the mechanical engineers have
reached the limit in designing steam
boilers and steam-boiler furnaces, espe-
cially so on the factor of efficiency and
economy, and it matters not how good
the whole equipment may be or what
quality of coal is used if the important
particulars are lost sight of, such as at-
tention to temperature and capacity; all
other efforts toward efficiency and econ-
omy in the performance of the plant
will be in vain.

Therefore, chief engineers as well as
chief firemen should broaden out in their
treatment of their firemen, and care-
fully instruct them in the performance
of their duties; they should encourage
them in improving their efforts to qualify
for the high positions in the engineering
line. This in time will make them more
proficient in steam-boiler and steam-en-
gineering work than is the average tech-
nical graduate who is fast relegating
the practical man to the rear on nothing
but pencil and pad work.

J. J. McAndrew.

Scranton, Penn.

Coal Defined

In the issue of May 30, William Kent
presents a criticism of my article, "The
Coal Problem Analyzed," which appeared
in the issue of April 25. He objects to
my invention of new terms, such as "fuel
mixture" and "coal fuel," as being
neither necessary nor justifiable. I think
the reason for my adopting such new
terms was so clearly set forth in the
article that the readers of Power may
judge for themselves as to the merits
of the case.

It seems well to call attention to the
danger of being overconscrvative in mat-
ters of this kind. It is, of course, true
that an unnecessary word or term, or
any useless thing for that matter, is
objectionable. But the history of all
languages contains unending examples
of new words and terms, made necessary
by the progress of civilization and the
arts. The Century dictionary, to which
reference is made, is an instance, as it
was necessary to issue 10 volumes in-
stead of a lesser number because of
the new words and definitions that must
be included, but which had been absent
in other dictionaries. Because people
thought for several hundred years that
the world was flat was no reason why
the more authentic view of its spherical
form should not have been accepted.

Since preparing the foregoing, Mr.
Kent's correction appearing on page 927
of the issue of June 13 has come to my
attention. At the time, not being able *
to gather his meaning. I did not attempt
an cvplanation. It is now clear, how-
ever, that he proposes (as he has many
times before) a different definition for
the term "pure coal." When I began

220

POWER

August 8. 1911

to study the coal problem several years
ago, I found that the ash- and moisture-
free coal was universally called "com-
bustible" by engineers. As I wished to
use the word in its correct sense, name-
ly, to define the combustible elements,
I adopted the term "pure coal." Mr.
Kent's argument is not consistent. He
maintains that pure coal should consist
only of combustible elements, not con-
ceding to it oxygen and nitrogen; yet he
would have "coal" consist of coal and
dirt.

A. Bement.
Chicago, 111.

Pins in Loose Crank Pins

In Power for July 18, B. W. Robin-
son sizes up the loose cranlc-pin sub-
ject quite well; but we have dealt suc-
cessfully with the same problem in a
different and, I fancy, better way.

We drill and ream a taper hole in
the center of the pins to quite the depth
of the crank, and drive in a taper pin.
(Do not heat the crank pin as that closes
■up the hole, contrary to one's first no-
tion.) The first job of this kind we had
was when the main bearing of a Corliss
engine 10-inch cast-iron shaft got hot
and expanded the crank until it became
loose. We drilled and reamed a 2V^-
inch hole in the center, after the fore-
man had failed in helping it with a 1'4-
inch taper pin in the joint. The tapered
steel pin driven in the middle of the
shaft helped matters considerably, but
did not cure it until the shaft again
became heated, and the crank set tight;
it has remained so for about 45 years.

We have repeatedly turned the same
trick on crank pins successfully.

John E. Sweet.

Syracuse, N. Y.

Poor Draft

I read Mr. Cotton's description of his
draft troubles in the July 4 issue. A
smoke connection should have a sec-
tional area at least equal to that of all
the tubes in the boiler which it serves.
In Mr. Cotton's layout this is not the
case which, no doubt, is part of the rea-
son for the sluggishness of the draft.
The total area of the 70 tubes, 4 inches
in diameter, in each boiler is 880 square
inches while the area of the uptake con-
nection, 10 inches wide by 67 inches
long, is only 670 square inches.

Further, the area of the stack itself

is only 2290 square inches while the total

tube area for all three boilers is 2640

square inches. Thus the stack itself is

• much under the proper size.

The commercial capacity of the stack
is about 400 horsepower while that of
the three boilers is about 480 horsepower.

I think that the only remedy Mr. Cot-
ton can apply is to increase the size

of the smoke connections and stack or
else put in a small blower to increase
the draft power.

C. R. McGahey.
Baltimore. Md.

Advantages of Open Feed
Water Heaters

The answer given to O. C. H.'s ques-
tion in the July 18 issue of Power, "What
are three advantages of an open heater
over the closed feed- water heater?" is
very good, but does not mention half
the advantages.

First, some types of open heater will
maintain a . higher temperature of the
feed water.

Second, it is generally used as a re-
ceiver for the return from the heating
system, thus saving the expense of a
return tank necessary to supply the feed
pump when closed heaters are used.

Third, with proper baffle plates and
float valves it acts as an oil separator,
collecting the cylinder oil from the ex-
haust steam and conveying it to the soil
pipe, thus keeping it out of the boilers
and heating systems. With the overflow
controlled by a float valve it will also
act as a return trap, keeping the end of
the return pipe water sealed, and prevent-
ing the escape of steam if live steam is
used for heating when the engine is not
running.

With the Cochrane feed-water heater
the temperature runs from 200 to 214
degrees, and the greatest trouble was
to prevent the feed water from becoming
too hot, or the feed pump would become
steam bound.

R. A. CULTRA.

Cambridge. Mass.

Hot Boxes and Some Cures

I have been reading with much in-
terest the various articles on hot boxes
and the many different remedies used,
sulphur being the bone of contention.
The proper kind to use is what is called
flour of sulphur, and not the ordinary
commercial kind. Being the flour of a
solid substance, we must remember that
if it is subjected to pressure or con-
fined in too close a space in a bearing
the results are as liable to prove detri-
mental as beneficial. Like graphite,
sapolio, soapstone, etc. it must be
used with oil in the proper pro-
portion and be kept moving in order
to do anything toward cooling the bear-
ing. The use of sulphur in a bearing
will give a beautiful gloss if any results
are obtained at all.

Most any of the so called flour or
powder remedies are good to use in a
bearing when there is sufficient jar or
room to allow these substances to work
under and around the shaft, such as is
afforded in the main bearings of most

engines. Be careful of what you do
when it comes to handling close bear-
ings, such as outboard bearings on en-
gines, motor bearings or any bearing
where there is no vibration or thrust
to assist the working of the remedies.
Cylinder oil, white lead and refined tal-
low are good remedies for close bear-
ings, either brass or babbitt lined. Mr.
Holly's water remedy will work all right
on brass- or composition-lined boxes,
but in babbitt-lined ones I would ad-
vise a close observance of temperature
of the bearing before applying water, or
queer things may happen. Good castor
oil free from resin or other body sub-
stances is frequently used with good re-
sults in cases of chronic heating. Pure
white lead is about as effective when
mixed with either linseed or cylinder oil
as any remedy I have tried.

To cool any hot box one should al-
ways select such remedies as are in
themselves good lubricants and of higher
fire or flash test than the possible tem-
perature of the bearing. Locate the cause
and it will usually suggest the remedy.
Thomas M. Sterling.

Middlebranch, O.

Sizes of Belts

In "Notes on the Size and Care of
Belts" in the July 4 issue of Power,
W. R. Willard. in giving his method for
finding the width of belt necessary to
transmit a given power, seems to have
confused the difference ^^ — T- with the
quantity T- itself. Using Mr. Willard's
notation, the difference P in belt pull
on the tight and slack sides of the belt
is also equal to the difference 7", — T-,
as these quantities are defined at the
bottom of the table. The width of belt
is based on 7i. To find 7",, Mr. Willard
multiplied his value for P by the value
of 7", -^ 7"; taken from the table; he has
evidently called P = 7",, whereas P =:

Having T, — 1-. — 218.8 pounds and
7, -H T; = 2.311, we can easily solve for
r,, obtaining 7", = 385.7 pounds. Using
Mr. Willard's assumption that single
leather belting will pull with safety 80
pounds per inch of width, the required
width will be 4"s inches instead of 65s
inches as found by Mr. Williard.

It is true that as an approximation
7, — 7", is often taken equal to 7":, but
this necessarily makes T, -h T - = 2, cor-
responding to an arc of contact of 180
degrees and f = about 0.22; we cannot
take 7, — 7j from the table and still use
7i — 7= 7.. The correct method is
to find P, or what is the same thing
7, — 7l. as Mr. Willard has done, from
the power to be transmitted and the belt
speed. Then take 7, -^ 7, from the table
according to the conditions of the case,
and solve for 7,. This value of 7, divided
by the assumed safe load per inch of
width win give the width of belt re-

August S, 1911

quired. This method reduces to the fol-
lowing formula:
Let
S = Speed of belt in feet per min-
ute;
//= Horsepower to be transmitted;
/?= Ratio of tensions, T, -^ T: as

found from table;
L = Safe working load per inch of

width of belt;
H'^ Width of belt in inches.
Then

'sxLx (fi — i)
Thus in the problem under discussion
we have

IF — •

W

_ 33,000 X 25 X 2.31 1

: 4J inches

3770 X 80 X 1.3 1 1
The value of 80 pounds for safe work-
ing load per inch of width, as taken by
Mr. Willard, is rather high for single
leather belting, 60 pounds or less be-
ing more often used.

William Earl Mosher.
Alechanicsville, N. Y.

Putting in Gage Glasses

In a letter under the above title in
ER for June 20. Mr. Little says that

- washer furnished with the gage fix-
lures is often placed in the bottom of
the nut. That is just where it should
be placed. If it is not so used the glass
■Aill often be twisted off by reason of
the adhesion between the nut, packing
and glass, despite the use of graphite.
George R. Willia.ms.

Findlay, O.

Coitral Station versus Isolated
Plant

In PovcER for July 1 1 I noticed an arti-
cle by Emmet Baldwin entitled "Central
Station versus Isolated Plant" and one
by Mr. Westerfield under the title, "Writ-
ing for the Technical Paper." I heartily
agree with the latter gentleman, whose
words are designed to help those who are
backward in giving others the benefit of
their experiences. His article and that
of Mr. Baldwin compel me to say a few
words. I am interested only because I
am an engineer in an isolated plant. I
do not like to criticize, yet there is an
opening for discussion.

I believe Mr. Baldwin has given up his
plant too easily: because he did his own
firing does not establish the fact that
he was getting the best results from the
co.-il. The condition of the boiler is to be
:dered as well as that of the engine,
i-reaf many engineers think that if
til' engine is all right and running eco-
nomically they have nothing to fear.
They never stop to think whether the
condition of the boilers can be improved.

just how much coal Mr. Baldwin
means when he says, "somewhat more
than two tons" is not known. If he had

POWER

checked up he would have known exact-
ly how much he was using and what the
watchman was usin^. Then, he could
have given accurate figures as to how
much it cost to develop the power re-
quired, and whether the conditions could
have been bettered.

I will endeavor to give a little of my
experience in this discussion. In the
first place, I keep an account of all of
the coal delivered to my plant. I fre-
quently indicate my engine and check
up on my fireman. The engine is de-
veloping 112 horsepower. The fireman
has demonstrated time and again that he
can fire the boiler with 392 pounds of
coal per hour or 3'< pounds per indi-
cated horsepower per hour. For a ten-
hour run it will take 3920 pounds of
coal.

Last winter I was called on to check
up with the firm. The figures showed
more coal than they thought necessary,
so I checked up on the fireman and
found him to be within the limits. Then
I thought the trouble must be with the
watchman as he had never been on duty
in the winter when we had to have the
plant heated. I gave him a few lessons
in handling his fire. The result was we
saved nearly 1', tons of coal in the
next month. This is quite an item for
a beginner.

Aly point is this: If the isolated plant
can produce power at or in the neighbor-
hood of S'/j pounds of coal per horse-
power-hour and heat the building with
the exhaust steam in the winter time,
the engineer need have little fear of the
central station. What is wanted in the
isolated plant is wide-awake and upto-
date engineers. Then the central-sta-
tion man will have a hard time to dis-
place them.

A. C. Schneider.
De Soto, Mo.

Belt Drives

In the July 4 issue the article by W. R.
Willard contains some very useful in-
formation and with one exception is cor-
rect; his suggestion of the second tight-
ener, shown by dotted lines in Fig. 3 of
his article, I think is wrong.

In a small electrically driven plant I
had been called to install some machin-
• ery which included a vertical drive with
a tightener to allow for stopping a part
of the plant if required, as the firm did
not want to install a friction clutch on
account of the cost. The plant was idle
when I arrived, owing to a burned-out
motor. The direction of rotation of the
shafting was given me by one of the
owners and the required shafting put up.
When I started up to try things out I
found the shafting was turning in the
opposite way from the direction the
owner had given me, and my tightener
was on the side as the one shown by
Mr, Willard in dotted lines, assuining the
belt to be turning to the left. As the

221

driving and other conditions would not
allow reversing the motor, I decided to
make the tightener work. 1 did this by
a liberal application of old junk as a
weight and I was surprised at the amount
it required to make my shaft turn when
the load came on. That night I changed
the tightener to the other side and it did
its work easily without any weight ex-
cept its own, and the bearings ran sev-
eral degrees cooler.

In another case I had charge of a
mill of which the upper-floor machinery
was driven by the vertical belt and
tightener system.

Wishing to stop the shafting on this
floor and not interfere with operations
on the floor below, I sent a man down to
raise the tightener; he did and secured
it with the latch provided for that pur-
pose. When he came back to assist me
the speed had not slackened in the
least, so I went below myself to investi-
gate. I found the belt, which was 16
inches wide, hugging the small pulley
in the same position that it should had
the tightener not been removed. It took
some little effort to persuade the belt
to let go.

With these two experiences in mind I
am convinced that the tightener should
be on the slack side of the belt where
the sag will assist it in taking up the
slack and not on the tight side, which
has a tendency to run straight, owing
to the pull.

Air. Willard's argument of getting a
large arc of contact on the small pulley
is a good one, but it will take less power
to run the shafting if this increased arc
of contact is obtained with one idler,
which can be done by leaving the belt
longer and letting it run as close to the
tight side as is required to get the maxi-
mum efficiency.

Charles F. King.

Portland, Ore.

Receiver Pressure

In June 27 number of Power, E. H.
Lockwood takes exception to my state-
ment that the shorter the cutoff in the
high-pressure cylinder the less is the
consumption of steam. I do not think
his illustration of the pump going faster
with higher receiver pressure and slower
with less receiver pressure proves any-
thing, for the engine has no governor at
all; besides, the load and relative sizes
of the cylinders have all to do with the
necessary receiver pressure. I would
not care to tell the exact receiver pres-
sure best to carry, but I think where
both cylinders arc working under the
best condition with regard to pressure, it
will be found that either raising or
lowering the receiver pressure will cause
the governor to revolve in a lower plane
and a greater amount of steam will be
consumed.

L. Johnson.
Exeter. N. H.

POWER

August 8. 1911

Capacity of Taper 'Tanks

I have a tank forming the frustum of
a cone. The bottom diameter is 5 feet,
the top diameter is 4 feet and the hight
is 5 feet. How can I find my marks
for 100 gallons, 150 gallons, 200 gallons,
etc.?

A. 0. L.

To mark off on a tank which is the
frustum of a cone the hight to which
a given volume of liquid will fill it re-
quires the calculation of the contents of
the cone of which the frustum is a part
and the hights of the several cones each
of which shall contain a specified vol-
ume less than the original cone.

The hight of the whole cone of which
the tank is a frustum is 25 feet, con-
taining 1223 gallons. As the volume
of all solids is proportional to the cubes
of their corresponding dimensions, a
cone having a volume of 1123 gallons
will have a hight expressed by the pro-
portion

1223: 1123: :25':ar
To shorten the operation it may be
changed to read

then

1 123; -.25 -.x

,y-

23 = 10.694
f/ 1123 = 10.3943

10.694: 10.3943: : 25: 24.29

X = 24.29

25 — 24.29 — 0.71 foot

0.71 V 12 = 8.52 inches

the hight to which 100 gallons will fill

the tank.

For the next mark subtract 150 from
1223 and proceed as before

1223 — 150 = 1073

■f/ 1223 : f^ 1073 :: 25 : j:

10.694: 10.2376:25:23.93

25 — 23.93 = 1.07 feet

1.07 X 12 = 12.84 inches

the hight of mark for 150 gallons, and

so on until the desired number of marks

is made.

Compressor Capacity, Horse-
power and Piston Speed

How is the capacity of an air com-
pressor computed? How is the horse-
power computed? What is the most eco-
nomical piston speed for an air com-
pressor?

H. C. E.

The nominal capacity of air com-
pressors is commonly reckoned to be the
theoretical piston displacement. The
actual capacity is the piston displace-
ment multiplied by the volumetric effi-
ciency which is the actual piston di'<-

placement dividec by the theoretical.
This does not include the leakage of air
past the piston.

The indicated horsepower in the air
cylinder is for simple stage compres-
sion,

I.H.I'.= 1.51 P, (/?U-29— l)
and for two-stage compression with inter-
cooling and with equal compression ratios
in the two cylinders.

l.H.r. = 3.02 P, (/J0.U5 _ i)
in which

Pi = Absolute initial pressure;
R — Total ratio of compression.

For the air cylinder alone a low pis-
ton speed is more economical than a
high one, but when other factors are
considered, the highest practicable speed
(depending on valve area, etc.) is the
most economical.

Fusible Plugs

Why should -the least diameter of
fusible metal in a fusible plug be not less
than 'Z- inch, and why should the plug
project through the sheet 1 inch or more?
Why not use an inside plug on a re-
turn-tubular boiler? What types of boil-
ers have inside plugs?

J. C. O.

The diameter of fusible metal is made
V, inch to avoid a possible choking of
the orifice by scale or floating sludge
and to allow steam enough to es-
cape to attract attention. The plug
projects through the plate .1 inch to pre-
vent the catching of floating matter that
would be close to the head. Outside
plugs are used in return-tubular boilers
because they are more accessible than
inside ones. Inside plugs are used in
vertical fire-tube boilers and the fusible
metal is usually 's inch diameter be-
cause a larger diameter will not easily
make a good joint in a boiler tube.

Safety Valve A rea
How many square feet of grate sur-
face would be allowed for a safety valve
3 inches in diameter?

W. G. A.

The Massachusetts formula for spring-
loaded safety valves is
"■70

in which

A =rz Area of valve in square inches

per square foot of grate;
W = Pounds of water evaporated per
second per square foot of
grate;

P = Absolute pressure at which the
valve opens.
As the valve area depends on the
amount of steam made and its pressure,
these must be assumed to find the grate
area to fit the valve. Take 160 pounds
of water evaporated per hour per square
foot of grate into steam at 100 pounds
gage pressure. Then the weight evap-
orated per second will be 0.0444 pound,
and substituting the values in the equa-
tion it becomes

0.0444 X 70 X II . ,
; = 0.297 square tncn

of valve area for each square foot of
grate. The area of a 3-inch valve is
7.0686 square inches and it will take
care of as many square feet of grate
area as 0.297 is contained times in
7.0686.

7.0686 _

0.297 "

23.45 square I

Air Recjuired to Bum Coal
How do I compute the quantity of air
required to bum 1 pound of coal hav-
ing 80 per cent, carbon, 7 per cent.
hydrogen. 10 per cent, oxygen and 3
per cent. ash. What is the heat of com-
bustion?

R. B. C.
The air theoretically required to bum
one pound of coal is expressed by the
formula

I i.,S2 C + 34.56 (// _ ^) + 4.3, s = air

> in which

C = Per cent, of carbon;
// = Per cent, of hydrogen;
O = Per cent, of oxygen;
S = Per cent, of sulphur.
Hence

1 1.52 X 0.80 + 34.56 (0.07 —^^j =

1 1.203 pounds

The heat value of the fuel is 14,600
B.t.u. for the carbon, 62,000 B.t.u. for
the hydrogen.

14,600 X 0.80 -f- 62 ,000 (0.07 ^ J =

15,245 P./.U.

August 8, 1911

POWER

Issueil Weekly by the

Hill Publishing Compan^•

JOBW A. Hill, Pren. anil Treas. Rob't SIcKlan, Sec":

505 Pearl Street, New York.

122 South Mlchi;,-«n Boulpvard, Cliicago.

6 U.>iiv..rJi^ Street, U.ir.loi., E. C.
Coter den Liiideu ,1— Betliu, K. W. :,

Correspondence suitable for the col-
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must be given — not necessarily for pub-
lication.

Subscription price S2 per year, in
advance, to any post office m llie I nited
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.States and .Mexico. S3 to Canada. So
to any other foreign country.

Pa.v no money to .solicitors or agents
iinless they can show letters of authoriza-
tion from this office.

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Hemisphere may send their sub.scriptions
to the London Office. Price 21 Shil-
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Entered as second class matter. De-
p<"mber 20, 1910, at the post office at
New York, New York, under the Act
(if March 3, 1879.

Cable address, " Powpu

Business Telegraph Code

N'. V.

li:ri LATios

■>jATL\i!:\ r

01 thit isrue, 31,000 copies arc printed.

Konc tent free rcijularljj. no returns fron
neurs companieti, no hack numbers, Figum
art live

net

culalitjii

Contents i..vi;i:

ExiensloD of Redondo Il.-acn I'l.int 198

V •■ of a Vacuum 202

tig Receiver to Heat Feed Water. . 203

rresstire of Expanding Steam 204

I of Indicator Reducing Rigs 206

Hpeed versus Economy of Eni;ines 207

The Price Water Current Motor 208

Installation of Small Stationary Engines 209

tias Engine Ignition Equipment 210

Crude Pelroleiiiii 211

Producer Capacity When Operating on

I.Ignlte 211

Udii!iiirI Packing Ring Reinforcement... 211

The Remek Transformer 212

The Electrical Section of the niircaii of

Mines 21.'!

~ Iliase. Three-Phase Transformer

iinectlons 214

L' Out Dynamos from Parallel

Service 214

iTarilcal I-etters :

Receiver Pressure Spring Rotls. . . .
Smoke Preventer. .. .Clogged Con-
denser f;age Pipe. ... Lining Water
Id Rollers. .. .Running n Pump with
Rrnlten Cylinder Mend. ... Repaired
Engine Krame. . . .fdling Kinks....
Preventing Steam Tiirlilnes from

Racing 215-217

Dturiisslon I,et|ers:

Poor firnft .... What Cniises the
Pipe to Wear. . . .Floller Mnnngement
....Holler Iteslgn. .. .Value of Klue
':«• Analysis .... Conl fxilned. . . .
Iin« In l>wi.e Crank Pln«....A(l-
nlnge» of Dpen K<ed Wnter Ileat-
■" ...Hot Fioxes iind Some Cures

HIzeB of Belts Pulling In

n«ge 'ilasaes . . . . Cenlrnl SInllon
versus Isrdnted I'InnI .... Belt

I ''Ives 21**-221

"Is 22.1-224

' ''sses through Insulation 22."

•ns on Refrlcernllon 220

" Accident nl RIverlon, lilt 227

Condensers

In stationary work the jet type of
condenser is still holding its own be-
cause of its much lower price and equal
if not superior adaptability to the needs,
particularly in situations where fresh
water is available for condensing, al-
lowing the feed to be taken from the
overflow of the hotwell at a tempera-
ture depending on the vacuum carried.

The statement is often made that
there is an element of danger in the op-
eration of a jet condenser because it
is possible under certain conditions to
flood the engine cylinder and cause
a wreck.

There is an element of danger in the
operation of any machine, however
simple it may be, if put into the hands
of unskilled men. But with the intelli-
gent engineer there is no more danger
of accident to the engine from the jet
condenser than from any other part of
a modern power plant.

With the surface condenser the pos-
sibility of getting water into the steam
cylinder is, of course, eliminated, but
this is no reason why its operation
should be entrusted to an unqualified
man as there are ways of wasting
money in a power plant other than by
wrecking engines.

In many situations the surface con-
denser is to be preferred to the jet for
reasons that are seldom recognized.
Accurate records of the amount of water
fed to the boilers may be kept, but
these records afford no information as
to the proportionate quantity of steam
that is being used by each or any unit
in a condensing plant where more than
one unit is used. Weighing the water
drawn from a surface condenser and
comparing this weight with indicator dia-
grams or with switchboard records for
any given period will furnish informa-
tion that can be gotten in no other way.

In many large and some small plants
the discharge from the air pumps of the
surface condensers is piped directly to
weighing tanks so that the water con-
sumption of any unit operating under
any condition may he measured at any
time without preparation.

There come times of emergency in
every plant and one of these times may
be caused by a near or distant fire or
by the wafer being shut off in the
vicinity of the plant for repairs or
changes in the water main, causing a

temporary curtailment or perhaps a
complete stoppage of the feed water
supply. In such a case the surface
condenser with its air-pump discharge
piped to a reservoir from which the feed
pump may draw is invaluable if con-
tinuous service is desired.

Mas,sachu,sctts Standartl toiler
Rules

That the standard is high for the
Massachusetts boiler rules is amply evi-
denced by the facts brought out at the
twenty-third annual convention of the
.American Boiler Alanufacturers' Associa-
tion recently held in Boston, Mass.

It is claimed that, conservatively es-
timated, there are 24,000 boilers under
the provisions of the boiler-inspection
law, and that less than two one-thou-
sandths of one per cent, of this number
of boilers in use in the State of Massa-
chusetts show any explosion. This low
percentage is believed to be due chiefly
to the specified boiler design and the
rigid inspection laws that are well ad-
ministered and thoroughly and practical-
ly formulated.

The State is divided into seventeen
districts and twenty-five inspectors hold
certificates of competency as inspectors
of steam boilers. That the Common-
wealth fully believes in the good that is
being accomplished by the steam-boiler
Inspection department, is evidenced by
the appointment recently of five addi-
tional inspectors.

While some opposition was manifested
at the convention to the proposal that
the Massachusetts standard boiler rules
be made standard for all boiler manu-
facturers throughout the United States,
It appeared to be the general belief that,
with some slight changes in detail as
necessary to local conditions, the rules
of the Bay State were best adapted to
the States as a whole.

A number stated that the high stand-
ard set by Massachusetts is favorably
known outside the confines of this coun-
try, and manufacturers have been asked
to figure on boilers built under this
standard in the Philippines, Constan-
tinople, China and ,|apan.

Its most earnest adherents did not
claim that the Massachusetts standard
was flawless; they said they were ready
at all times to modify a rule where sufB-
cicnt reason could be shown.

224

Redondo

In this issue we describe the enlarge-
ment of the Redondo Beach generating
plant. At the time of its erection this
was perhaps the most widely advertised
central station in America by virtue of
the decision of the engineers to install
5000-horsepower reciprocating engines in
preference to steam turbines. It was
almost universally expected that the en-
gineers would follow the lead established
by the New York Edison Company, the
Boston Edison Company and the Com-
monwealth Edison Company, of Chicago,
all of which had declared in favor of
the turbine by installing this type of
prime mover in their stations.

When the results of the acceptance
tests at Redondo were made known, the
engineering world was startled by the
fact that a world's record for overall
plant efficiency had been established
Something like 235 kilowatt-hours had
been generated per barrel of oil. But,
just what part the engines played in
the securing of this result was never
publicly made clear. The opinion is
prevalent, however, that the record was
established not so much through any
surpassingly high engine efficiency but
by getting from each individual piece of
equipment the best results it was cap-
able of yielding. Paraphrasing a familiar
axiom it might be said that they took
care of the small individual efficiencies
and the big overall efficiency took care
of itself.

When the enlargement of Redondo was
announced, speculation became rife as
to what type of prime mover would then
be selected. Few expected that more
reciprocating engines would be put in;
the points in favor of the turbine were
too obvious to permit of such an ex-
pectation. In view of the showing made
by the exhaust-steam turbines in the
Fifty-ninth street station of the Inter-
borough Rapid Transit Company that
type of machine seemed the logical selec-
tion. However, the time element threw
it out of the running and the high-
pressure turbine was selected.

In southern waters the marine-plant
growths are rank and almost endless in
variety. During certain times of the
year weeds and leaves float about in
huge masses below the surface of the
water. The problem of excluding this
decaying vegetation from the circulat-
ing-water system without too great an
expenditure for duplicate equipment or
the employment of an excessive amount
of manual labor has been no easy one to
solve.

That the original circulating-water
system at Redondo did not constitute a
satisfactory solution of the problem was
made evident by the numerous interrup-
tions that occurred in the condensing-
water supply. If complete-expansion
turbines are to be of any use whatever

POWER

they must have an ample and continuous
condensing-water supply. Realizing this,
J. G. White & Co., the consulting engi-
neers for the work of enlargement, spent
some hours in earnest thought and
evolved the circulating-water system de-
scribed in the article appearing in this
issue. It is radically different from the
original arrangement and its simplicity,
low first cost and efficiency stamp it as
being an unqualified success.

Riverton Turbine Accident

Boiler explosions, on account of their
frequent occurrence, now cease to excite
more than a passing or a local interest,
unless extremely disastrous in extent,
or occurring under unusual circum-
stances. Similarly, flywheel explosions
have become more or less cornmon, and
the causes which lead to them are usu-
ally obvious. A turbine explosion, how-
ever, is rare. This fact, together with
the apparently normal conditions under
which the accident occurred at River-
ton, will furnish a topic for much spec-
ulation among the engineering fra-
ternity.

If the turbine was running at half
speed when the accident happened, as
stated by an eye witness, then it is plain
that it was not due to an old fracture
in the metal or to any inherent defect
in design; for the machine had been
operated for several years at normal
speed without giving the slightest trou-
ble. According to this, the theory that
some foreign object had become lodged
between the rotating and stationary
parts would seem plausible.

On the other hand, if the governor
failed to operate properly and the ma-
chine speeded up, the cause of the acci-
dent can be easily explained.

On account of the reluctance of the
company to give out information and
their strict rules barring the use of
the camera, it is difficult to form a con-
clusive opinion which would be of bene-
fit to engineers operating other turbine
plants.

Opportunity for the Isolated
'plant

One of the weapons of the central
station in its arguments against the iso-
lated plant has been that the latter is
handicapped by a low load factor. Ac-
cording to the latest developments in
the controversy now being waged in
New York city, the central station ad-
herents will have to look to other lines
to back up their case.

The Longacre Light and Power Com-
pany, which has long been fighting a
legal battle for a franchise in New-
York City, has at last received permis-
sion from the Public Service Commis-

August 8, 1911

sion to issue bonds to the extent of
fifty million dollars. Furthermore, they
may use the present street conduits for
their cables.

One of the first moves of this com-
pany has been to issue a statement to
isolated-plant owners that they stand
ready to purchase all excess power of
such plants at one and one-half cents
per kilowatt-hour during the daytime
and at one and one-quarter cents at
night.

This would enable the isolated plants
to be run at one hundred per cent, load
factor all the time, and the only addi-
tional expense would be for coal. Thus
the cost of producing electrical energy
would be cut down materially and their
position rendered more secure against
present central-station encroachments.

The opportunity appears to have ar-
rived for the small plants to show what
they can do.

Silent Running Engines

In deciding the degree of compression
necessary to produce a quietly running
engine, the engineer frequently calcu-'
lates the momentum of the moving parts
by multiplying their estimated weight
by the average speed of travel.

While the speed of the crank pin is
uniform throughout the stroke, the
speed of the piston ranges from zero at
the beginning of the stroke to approxi-
mately that of the crank at midstroke,
or more than three times its average
speed.

But as it approaches the end of its
travel the rate of speed rapidly dimin-
ishes, and at the end again becomes
zero.

The amount of compression needed
to transfer the pressure from one side
of the pins and main bearing to the
other at or near the end of the stroke
is but little above the terminal pressure
on the opposite side of the piston, and
if calculated for the average speed of
the piston for the last few inches of
the stroke it will be found sufficient for
most if not all cases.

In the reversal of pressure from one
side of all the bearing surfaces to the
other the change must be gradual if
quiet running is expected. But any
pressure in excess of what is required
for this change acts as a brake on the
engine and reduces its efficiency.

Where the compression is slight, the
lead, if excessive, will hasten the in-
complete reversal of pressure to an ex-
tent that will make silent operation im-
possible.

It is excessive lead rather than the
lack of sufficient compression that is
often the cause of noisy operation, and
the engineer finding relief in increased
compression hastily concludes that quiet
running is impossible without it.

P O \X E R

Cold Losses throuijh Insula-
tion
By F. E Matthews

There is no known means of accurate-
ly determining loss of refrigeration
through the opening of cold-storage
doors, although it might be roughly ap-
proximated from formulas giving the flow
ot gases under slight differences in pres-
sures, in which case some delicate form
of draft gage might be employed to show
the excess pressure of the coid air on
the inside of the cold-storage compart-
ment over that of the outside air. The
area through which the outwara flow due
to the observed difference ot pressure
would take place would be probably
about one-hdlf of that of the opening
ottered by the door, because in a single
openin.; the upper part would be given
up to the inward current of warm air.

While it would be difficult to estimate
the velocity at which coid air rushes out
of a cold-storage compartment, it is ap-
parent that it will increase as the dif-
ference between the inside and outside
temperatures and with the increase in
hight of the cold-air column, both of
these factors acting to effect an unbal-
ancing of the atmospheric pressures and
consequently tending to produce a flow.

In this connection it may be remarked
that the circulation of air in cold-storage
compartments, as well as currents of air
entering and leaving the compartment,
can be conveniently studied by using
smoke as an indicator. It might be po.s-
sible by means of a puff of smoke and a
stop watch, in the absence of a delicate
anemometer, to roughly determine the
velocity of the air currents. The inward
current would have a maximum velocity
at the top of the opening and the out-
ward current at the bottom, while some-
where near midvay would be found a
place with no perceptible curren'.. From
this it follows that the volume of air
lost through the opening might be deter-
mined by multiplying one-half the area
of the opening by one-half the maximum
velocity. The product of the f."eraRe
velocity in feet per minute and ihc area
of the current will be the number of
cubic ftet per minute lost throiigh the
Of nine, and, since 4000 cubic feet per
•' cooled one degree requires re-
ition at the rate of one top per 24
it follows that outside air at a tem-
irj of 80 degrees Fahrenheit, rush-
ito the cold-storage compartments
lo like the place of cold air cficaping

at a temperature of 40 degrees Fahren-
heit, requires an additional ton of re-
frigeration for every 100 cubic feet of
flow. To reduce this excessive loss to
a minimum, vestibules sufficiently large
to permit one door to be closed before
the other is opened are often provided
for doors communicating directly with
the outside. Where products alone are
to be passed, rotary doors, or 'n the
case of ice-storage rooms, automatically
closing swing doors may be advantage-
ously employed.

Insulation Losses

Good heat insulators are simply poor
heat conductors and poor heat insulators
good heat conductors — the property of
each being numerically the reciprocal
of that of the other. Since all heat
insulators are to some extent heat con-
ductors, the flow of heat through in-
sulated walls cannot be prevented but
only reduced in proportion to the thick-
ness and efficiency of the insulation used.
The amount of heat that will pass 'hrough
a square foot of cold-storage insula-
tion per 24 hours, like that through other
more or less imperfect conductors, is
practically proportional to the difference
in temperature on the two sides of the
insulat'on and to the efficiency of the ma-
terial not as a heat insulator but as a
heat conductor.

Products cooled to the temperature of
the cold-storage compartment where uni-
form temperatures are maintained re-
quire the expenditure of no further re-
frigeration. Exceptions to this general
rule are products which are fermented
while in storage, the process of fermenta-
tion giving rise to the evolvini^ of a
considerable quantity of heat.

The necessity for operating the refrig-
erating plant for the preservation of the
cooled products is therefore due largely
to the entrance of heat through the in-
sulated walls of the cold-storage com-
partments and the insulation should be
made as efficient as economy will permit.
True economy at the point where cost of
refrigeration would otherwise be lost is

balanced up against the cost of the in-
sulation effecting the saving. Obviously,
the more it costs to produce a ton of re-
frigeration the more it is economy to
employ insulation to conserve the re-
frigeration produced.

Ther.mal conductivity varies widely
among the so called insulating materials
and even with the same material when
varying percentages of air and moisture
are present. Table 1 shows the amount
of refrigeration expressed in B.t.u. per
square foot per 24 hours per degree dif-

TABLE 1. HE.\T CONDUCTIVITIES OF
COLD .STORAGE IN.SULATION

Transmission in B.t.n. per square foot per
ilccrec difference in leinperalun- in.side and out
per I'l hours. Compiled prineipallv from infor-
mal mn published by I he Armstrong Corl< Com-
pany.

Insulnling Slalix

n.t.u.

■ I.Uh

erproofed rock-wool
iieral-wooi flax-fiber

7.9

aterpioofed (same a-s above
waterproofed) 8.4

1" iini>regnated cork board (granulated
cork and a,s])baltic binder) 8.9

1' indurated fiber board (indurated wood-
pulp board 1 10.0

Buiit-up Imitlalion (wood and air space).

1" .\merican spnice 16.80

(J" dressed and matched spruce (j sp.)

paper. I sp.) (J sp. paper \ sp.) 4.75

(ii sp. paper i sp.) (1' air space) (5 sp.,

paper, 3 sp.) 4.25

6 thicknesses, i sp.. 3 papers, 2 air

spaces arranged as above 3.45

8 thicknesses. I sp.. 4 papers, 3 air

spaci's arranged as above 2 . 70

10 thicknesses \ sp.. h papers, 4 air spaces

arranged as above '2.70

(8 thicknesses being i and 2 thicknes,ses
being ii' thick)

Buill-up In.rutalion, Wood, Paper and Fill.
( j sp. paper, i sp.) (! sp. paper, J s.n.)
(Jsp. paper. ( sp.) (4'^raineral wool) ( J s

4.75

paper, I sp.) 2 , 20

(} sp. paper. | sp.) (8" mill shavings,

damp) (I sp. paper, I sp.) 2.10

(i SI). pa|)er. t sp.) (1" mill shavings, drv)

(sp. paper ,j sp.) 1 .35

(i ,«j). pai)er, I sp.) (8' granulated cork)

It sp. ])aper Jsp.) 1.90

Iier. i sp.) (1" nonpareil cork)
' - - ~ 10

(A sj) paiier. i sp.) (1" nonpareil cork)

I i sr> paper, J sp.) 3

(i sp. paper) d" nonpareil cork) (paper,

8 sp.) 3.25

(J sp. paper) (2" nonpareil cork) (paiwr,

J »p.) 2.60

(1 sp. paper) (3" nonpareil cork) (paper,

t sp.) 2.25

(i sp. paper) (1" nonpareil cork) (paper,

) sp.) 1.20

(I »p.) d" pilch) (! sp.) 4.90

(I sp.) (2" pitch) (I »p.) 4,25

Huill-up Intulnlinn (Il'ood, Paprr, Air Spare
and rill).

I) (I sp.. paper, i sp ).

(i sp. pa|M"r, i sp.) (I' air spario 1] sp.)
(rf* gran, cork) (J sp.. papiT. i «|>,).

(J "II. paper, t sp.i II air spaiio l{ .ip.)
2 nonp. cork) fi sp . paper, i sp.) —

(Jsp. paper, i sp ) (I'air spBci') (2" non-
pareil rotk* (paper. \ sp )

(J HP paper. J sp ) 'I'air spnci') (3* non-
pariil ciiik) (paper. ! sp '

(J "p paptr, J SI)-) n* air space) (■!' non-
pareil lorki (paper. 1 sp )

(1 sp. paper. I sp.) (!• air space) (.%' non-
pan-il cork I (paper, I sp.) . .

flrfrt Wall ami Sherl Cork.

(13' brick wall) (2" nonpariMl enrk)
(13* brick wain H' nonpar>-il lork)

1 49
I 46
1.60
2.10
1.70
I 20
0 90

226

P O W K R

Auguit 8, 1911

ference in temperature between the two
sides of the insulation. These values
represent efficiencies under best condi-
tions. In making computations for de-
termining the capacity of refrigerating
machines it is customary among some
builders to increase these values by from
25 to 50 per cent, according to the
physical condition of the insulation.

duct and the neutralizing of the amount
of heat generated by lights and workmen
entering through the opening of doors.

The 24-hour duty is now found by
multiplying 600, the number of square
feet of surface, by 5 the heat transmis-
sion per square foot, giving 3000 as the
number of B.t.u. per 24 hours per degree
difference in temperature. This multi-

T.\BIE •> VMUES OF CONSTANT K. POUNUS REFRIC.ER.\TING DUTY PER SQUARE
FOOT WALL SURFACE PER 24 HOURS FOR DIFFERENT INSULATION CON-
DUCTIVITIES AND DIFFERENCES IN TEMPER.\TURE ((—/'), INSIDE AND
OUT. NINETY DEOREES FAHRENHEIT ASSUMED OUTSIDE
TE.MPERATURE

Inside
Temp.

u-n

B.T.U. PER Sq.Ft prr Deorke Difference in Temperature per 24 Hours

1

2

3

4

5

6

7

8

9

10

50

■18

40
42

0.2772
0.2916

0 .5564
0.3832

0.8346
0.8749

1.111
1 .166

1.391
1.458

1.669
1.75

1.926
2.041

2.222
2.333

2.5
2.635

2.777
2.916

46

44

0 . 3055

0.6110

0.9165

1.222

1 . 527

1.833

2.139

2.444

2.749

3.055

44
42
40
3S

4G
48
50

0.3194
0.3333
0.3192
0.3611

0.6388
0.6667
0.6944
0 . 7222

0.9582
0 . 99UH
1 . 042
1 083

4.278
1 333
1 . 389
1 414

1.597
1.667
1 7.36
1.805

1.916
2.000
2.083
2 167

2.236
2.333
2.432
2.528

2.555
2 666
2.777
2.889

2.875
3.000
3.125
3.249

3.194
3.333
3.471
3.610

36

51

0.375

0.750

1.125

1.5

1.875

2.25

2.625

3.00

3.375

3 750

34

32
30

56
58
60

0 3809
0.4028
0.4166

0.7778
0.8056
0.8332

1.167
1.208
1.25

1.5.56
1.611
1.666

1.945
2.014
2.083

2 332
2 417
2.5

2.729

2.82

2.916

3.119
3.222
3.333

3.501
3.625
3.749

3.833
4.028
4 166

28

62

0 4306

0.8612

1 292

1.722

2.153

2.583

3.014

3.485

3.875

4.306

26
24
22

20

61
66

68

0 4114
0.45S3
0.4722
0.4861

0 . 8888
0.9166
0.9444
0.9722

1 333
1.375
1.417

1.458

1 778
1.833
1 . 889
1 944

9 22'^
5:292
2 361
2.431

2.666
2.75
2.833
2.917

3.001
3.208
3.305
3.403

3 553
3.666
3.778
3.889

4 000
4.125
4 230
4.373

4.444
4.582
4.722
4.861

IS

72

5.0

1.0

1.5

2.0

2.5

3 0

3.5

4.0

4.3

3,0

16

14

12

10

8

S

4

2

0

— 2

—4

—6

— s

— 10

71

76
7S
80
82
84
86
88
90
92
91
96
9S
lUO

0 5139
0 5238
0.5417
0 5556
0 5694
0.5833
0.5971
0.6111
0.625
0 . 6388
0.6526
0 0066
0 . 6805
0 B942

1.028

1.056

1.083

1.111

1.139

1.167

1.194

1.222

1.25

1.277

1.301

1.333

1.361

1.388

1.542

1 . 583

1.625

1.667

1.708

1.75

1.792

1 . 833

1.875

1.916

1 . 958
2.000

2 . 165
2.083

2 056
2.111

2 IfiT

2 . .i.vj
2.444
2.5
2 . 5.53
2 610
2.666

2.778

2.569
2 639

2 7(18

2 .986
3.056
3.125
3.193

3 262
3 .333
3.470
3.192

3.083

3 167

3.25

3 333

3.416

3.5

3.583

3.667

3.75

3. 835

3.913

4.000

4.82

4. 167

3.597
3.695
3.792
3 889
3.986
4.083
4.180
4.278
4.375
4.468
4.565
4.666
4.762
4.861

4.111

4 222

4.334

4.445

4 355

4.666

4.778

4 889

5.000

5.110

5.22

5.333

5.442

4 623
4.730
4.875
3.000

5 125
5.250
5.375

5 300
3.625
5.750
5.873

6 000
6 125
6 230

3.139
3. 278
3.417
3.555
5.694
5.833
5.972
6.111
6 250
6 388
6 526
6.666
6 805
6.942

Assuming, for example, a cold-itorage
box lO.xlOxlO feet, the superficial sur-
face exposed is 600 square feet.

The insulation is found to consist of
two courses of Js-inch dressed and
matched spruce with a course of paper
between, a 1-inch air space and two more
courses of spruce with paper oetween.
The conductivity of insulation of this
construction fs given in the table as 4.25
B.t.u. If the insulation is found to be
moist, about 20 per cent, may be added
to the above value, which brings the heat
transmission up to about 5 B.t.u.

As a matter of fact, 5 B.t.u. per square
foot per degree difference in tempera-
ture is often employed where the exact
value of the insulation cannot be deter-
mined, as an approximate factor for es-
timating the total cold-storage duty re-
quired for small- and medium-sized
boxes v/ith insulation of the, average in-
ferior quality conmionly used in mar-
ket and hotel refrigerators. The o.mount
of refrigerating duty estimated on this
basis should be ample to provide not only
for the insulation losses but for the cool-
ing of the average small amount of pro-

plied by 54, the difference between 90
degrees, the assumed maximum outside
temperature, and 36 degrees, the required
inside temperature, gives 162,000 B.t.u.
as the total heat absorbed.

This divided by 144 B.t.u., the amount
of heat required to melt a pound of ice,
gives 1125 pounds or 0.5625 ton as the
amount of refrigeration required per 24
hours to make up for insulation losses

A simple expression for pounds of re-
frigeration K, per 24 hours per square
foot of insulation, having a B.t.u. con-
ductivity C, per 24 hours per degree dif-
ference in temperature (t — h), is

K--

144

the

Substituting in this expression
values in the above example gives

/C = 5_>^ =1.875
144

which result multiplied by th3 total
square feet of surface, 600, gives 1125
pounds as before.

Table 2 shows similar values of K for
different insulation conductivities, rang-
ing from 1 to 10 B.t.u. per square foot

and for differences in temperature rang-
ing from 40 to 100 degrees.

To employ this table in the above ex-
ample. Pnd constant K =z 1.875 in the
horizontal line opposite (/ — t,) ^^ 54
degrees and in the vertical column under
C •= 5. This factor nuUtiplied by the
surface, 600, gives, as before, 1125
pounds, which divided by 2000 gives
0.5625 ton of refrigeration as the re-
quired capacity to make up for insulation
losses.

LETTERS

Questions on Refrigeration

I would like to have ar.swers to the
following questions concerning an am-
monia-compression plant with direct-ex-
pansion cooling system:

1. Should the discharge from the am-
monia compressor be hot or cold?

2. What are the causes for hot or
cold compressor discharge and how
remedied?

3. How can one tell whether or not
the expansion valve is far enough open?

4. When the suction pressure drops,
should the expansion valve be opened
more to maintain the pressure?

5. Can the compressor become so
cold that the water freezes in the com-
pressor jacket?

6. Will increasing the high or con-
denser pressure enable me to get better
results when the amount of ammonia in
the system is below normal?

7. Will some of the evaporating or
cooling coils show frost and others not
show it when the expansion valve is. not
opened wide enough, or when there is
little ammonia in the system?

8. When some of the coils are covered
with frost and some are not and the
discharge pipe is either hot or cold, what
does this indicate and what is the con-
dition of the gases in the coils?

9. Is there any danger when operat-
ing a cooling system with a high suc-
tion pressure?

10. To obtain the largest ice output,
should there be a large or small differ-
ence between the condenser and suction
pressures?

Delhi, O. E. J. Gale.

Flooded Sjstem

I would like to have the readers of
Power explain thoroughly the work-
ings of the fiooded system of refrigera-
tion. Can the capacity of the plant be
increased without increasing the coal
consumption? Is there any automatic
arrangement by which it is possible to
maintain an almost constant back pres-
sure?

Victor Bonn.

New York City.

August 8, 1911

POWER

227

Turbine Accident at Riverton. 111.

A peculiar accident occurred at the
power house of the Illinois Traction
Company at Riverton, 111., on Thursday
evening, July 20. A 2000-kilowatt, 4-
stage Curtis turbine was being started
and had reached about half speed when
the third-stage wheel gave way, breaking
half the casing of the steam end into
fragments, stripping off the cover on
the far side of the machine and send-
ing pieces flying in several directions.

The largest piece, about half of the
entire casting, took the direction indi-
cated by the dotted line A, Fig. 1, crack-
ing the bedplate of the engine-driven
exciter and breaking one of the supports
of the high-pressure cylinder of the Cor-
liss engine. The smallest piece took
the direction B, breaking the exhaust
pipe of the smaller turbine, then strik-
ing the bedplate of the Corliss engine
and making a 9xl'j-inch slot in the
heavy casting. Also, some smaller frag-
ments damaged the armature windings
of this machine. The third piece took
the direction C and struck the group of
ijien who were starting the turbine; two
of these were instantly killed ar)d two
others injured, one fatally; a fifth man
who happened to be standing near es-
caped without injury. It then knocked
over a 50-kilowatt motor-generator set

C^i.

Q Q Q U^ra„5fon

(— I |i_ v^ "\ lOOOtfn.Turbme I

Fin. 1. Plan of Enoine Room SHowrNC
Direction of Flying Frao.ments

While bringing the turbine
up to speed preparatory to
throning on the line, the
third -stage rotor let go, kill-
ing two men, seriously injur-
ing two others, and damaging
the other machines to such
an extent as to put the plant
out of service. The turbine
was a 20oo-k ilowatt, ^.-stage,
vertical Curtis machine.

boiler room were torn away, and the oil,
vacuum and water lines destroyed.

According to information furnished by
witnesses, the turbine was running at
about 400 revolutions per minute when
the rotor failed. The throttle was only
partly open, and the boiler pressure was
normal at 160 pounds. The step-bearing
pressure was 640 pounds, and there was

Fig. 2. Showing How Rotor Ruptured

no indication that it had decreased be-
fore the failure occurred.

Investigation developed that the tur-
bine had been shut down the previous
Monday for a general overhauling and
inspection. The steam end had been
opened, one section of the intermediate

shape. Thursday evening about 6 o'clock
the machine was started up cold pre-
paratory to throwing it on the line with
the smaller turbine, and had been run-
ning at about 400 revolutions per min-
ute for nearly ten minutes when the ac-
cident occurred. After the accident it
was found that the third-stage wheel
had been completely removed from the
machine and all that remained of the
third-stage diaphragm was a segment of
about a of a circle. The remainder of
these parts had been stripped from the
steam end as completely as if removed
by human hands.

One theory advanced as to the cause
of the accident, was that the repairs on
the steam end had caused the turbine to
be put out of balance and that the vibra-
tion resulting at the critical speed pro-
duced the failure of the third-stage
wheel. The grounds for this theory are
not well founded, as the machine had
been running for several years in perfect
balance, and as far as can be ascertained
the character of the work done on the
steam end when the turbine was down
for repairs was not of such a nature
as to put the rotating elements out of
balance.

Some engineers who have visited the
scene of the accident are inclined to dis-
regard the statement that the turbine was
running at half speed, and believe that
a defective governor allowed the turbine
to run above the normal speed, the noise
occasioned by the higher speed being
drowned by that of the other turbine
eight feet distant, and of the motor-
generator near which all of the men were
standing.

Another theory and one which seems
to be well borne out by the condition of
the machine, as observed after the ac-
cident, is that a nut, chisel or some other
tool, was left in the steam end when re-
pairs were made and this object be-
came wedged between the third-stage
wheel and the fourth-stage diaphragm,
thus starting the trouble. It was found
that although the fourth-stage dia-
phragm remained in place, it was badly
crushed around the inner circumference
as indicated in Fig. 3, tending to show

heel

Mefol of DiophrrJfjm

bndly crusheri'ot Hub

Fig. X Crusheo Diaphragm Shown by Dotted Lines

and completely demolished a lOO-kilo- holder had been removed and replaced, that some foreign object had become

watt transformer. The railings, piping the governor had been repaired and a wedged at this point and started a scor-

and connections on the turbines and in new set of bearings installed; to all ap- ing between the third-stage wheel and

the space between the machinery and the pearances everything was in first-class the diaphragm until the friction and the

228

POWER

August 8, 1911

building up of the metal at this point
split ihe third-stage wheel at its hub,
causing the fractured wheel to be
thrown away from the shaft by cen-
trifugal force, at the same time ex-
erting a tremendous leverage on the
cast-iron diaphragm above, splitting this
into a number of sections which, falling
down upon the rapidly revolving third-
stage wheel, were also thrown out by
centrifugal force. That the trouble
started at the place indicated seems very
probable, inasmuch as there are no muti-
lations on the piece of the third-stage
diaphragm remaining in the machine, the
only unusual condition being noted on
the top of the fourth-stage diaphragm.

Discussion at Boiler Men's
Convention

Following are brief abstracts of the
committee reports and discussions of the
twenty-third annual convention of the
American Boiler Manufacturers' Associa-
tion, held in Boston. July 10 to 13:

After the usual preliminary reports and
addresses, the following topical questions
were taken up:

1. (a) Will the present type of the butt
and strap joint fail frequently in the fu-
ture as the lap seam has in the past?

(b) Can the butt and strap joint be
inspected more thoroughly and with re-
liance upon conditions found ?

(c) Does the expansion and contraction
of the excess metal and rivets required
to make a butt and strap joint conduce to
greater or less efficiency of the joint?

?. What should be the ratio of thick-
ness between a convex and a concave
head based on the same radius, tensile
strength and working pressure?

3. Are the working pressures of steam,
where turbine engines are used, increas-
ing or diminishing?

4. Is it good practice to put turnbuckles
in stay rods?

5. In building heavy marine boilers
which is the better practice, to put holes
in plates before or after bending?

6. (a) Has the passing of laws and the
formulation of rules regarding steam
boilers reduced the number of explosions
or the disastrous results?

(b) If the steam boiler, or any prod-
uct, is considered dangerous to use or
operate but is allowed under regulations
of law, should the Government be held
responsible in case of disaster?

Taking up question No. 1, President
Meier said that there had been several
failures last year. Below- a certain diam-
eter, say, 36 inches, the value of a double
butt-strap joint is very doubtful unless
exceedingly heavy metal is employed. In
a shell carrying a working pressure of
500 pounds and tested to 000 pounds, it
was necessary to use the double butt-
strap joint. On such a small shell the
width of the joint is a large proportion

of the whole circumference, and the shell
does not expand like a cylinder. In diam-
eters of 60 to 72 inches this effect is not
so apparent. Joints of this description
must be made of reliable steel, say, the
A. B. M. A. steel, which was specified
as early as 1889.

In rolling for a lap joint and in form-
ing the double butt joint, the curve should
agree with the curvature of the shell.
When a crack is found, drillings should
be made around it; any competent chem-
ist can determine the cause of the failure
from these drillings. It should also be
ascertained whether the curvature of the
butt joint conforms to that of the boiler.
It was Mr. McCabe's belief that, while
not many flaws are found in the butt-
jointed boiler, they are common where
the plates are somewhat hard, and the
pounding action is bound to occur.

Mr. Ashley believed it necessary to
have a signed report from the inspector
in order to know that the steel is of good
metal within the particular limits of the
chemical characteristics, and that the
curves conform in general to those of the
boiler.

Regarding question No. 2, President
Meier said that while tensile strength has
its influence on the strength of the head,
the compressive strength is much greater.
The difference between a theoretical cal-
culation and a practical test must be
known. The tensile strength resists the
tendency of the material to flatten out.
Furthermore, the head is tied to the in-
side of the shell where the curvature of
the shell approaches that of the cylinder.
Hence, there is a claw-hammer action
which places the rivets in tension as well
as in shear.

Regarding the third question, as to
whether the working steam pressures,
where turbines are used, are increasing
or decreasing. President Meier said it ap-
peared that higher pressures were asked
for boilers where turbines were employed.
Mr. Hammond thought that no higher
pressures were asked for; in marine boil-
ers it was from 210 to 215 pounds.

Mr. Stevens stated that the guarantees
as to steam pressures are generally I
per cent, better for each 10 pounds in-
creased pressure; that is, if the guarantee
is based on 200 pounds. 250 pounds
would give a 5 per cent, better guarantee.
His company did not attempt to convert
the old plant where the steam pressure
was 150 pounds to the higher pressure;
the gain would be so slight that it would
not pay to rebuild the plant.

Mr. Hammond, in reference to question
No. 4, said that his company sometimes
had specifications requiring turnbuckles
in stayrods. though this demand did not
meet w-ith favor from his people.

As to question No. 5. Mr. Hammond
said that his practice is to first drill the
outside plates on the edge courses.
Where the butt straps come, a few
holes smaller than the intended size

are drilled to bolt up, followed by the
inner course. The heads are next put
in, the inside and outside straps are
put on and the holes are all in their
places. The plates are then taken apart
and the burrs removed before the plates
are put back for riveting. No punching
whatever is done on marine boilers.

Mr. McNeill said that legislation has
not only reduced the number of boiler
explosions, but it has done much to
discontinue the use of boilers which if
allowed to operate would result in ex-
plosions. Massachusetts has taken a
prominent part in bringing about this
much-needed remedy. In December,
1910, a disastrous explosion occurred in
Massachusetts, caused by increasing
the allowable pressure from 70 to 225
pounds, the safety valve having been
screwed down by a lii^ensed engineer.

To eliminate such a condition in the
future Mr. McNeill stated that it would,
in his opinion be necessary to place on
each boiler a safety valve, the adjusting
screw of which is screwed to a shoulder.
thus making it impossible to increase the
tension of the spring unless the boiler
were put out of commission or the ad-
justing screw was taken out or replaced
by a different one.

Another explosion happened in New-
Bedford in December, 1910. With these
two exceptions, no explosions have oc-
curred in Massachusetts since the pass-
age of the revised inspection laws in
1907.

Detroit and Michigan Ruli^s

At the fourth session the discussion
was on the Detroit rules and the pro-
posed Michigan rules as influenced by
the Massachusetts standard. President
Meier said that the city of Detroit had
practically adopted the Massachusetts
standard and he believed that the State
of Michigan was bound to do likewise.
Ohio had practically adopted them.

The absolute necessity for a standard
for specifications was cited in the ex-
perience of a Boston firm of contracting
engineers who received a contract for
construction work in Aberta, North-
west Canada. The company took with it
machinery which included a Massa-
chusetts standard vertical fire-tube
boiler for hoisting material. When the
boiler arrived it was found that it could
not be operated in Alberta because its
construction did not conform to the
regulations of the British Board of
Trade.

Discussion of Massachusetts Rules

The fifth session was mainly devoted
to discussion of uniform boiler inspec-
tion laws.

James C. Stewart said that it was
difficult to discuss this question without
entering into personalities. Public
opinion had been doctored regarding the
Massachusetts boiler laws; it was not

August 8, 1911

POWER

229

the opinion of Massachusetts men that
its boiler law was a model one; boards
of boiler rules and commissions could
not rule these men, said the speaker.
He believed that the State has throttled
the boiler maker and had taken care of
other interests. The makers could con-
struct a better boiler than the State; the
rules of the board had been spread
broadcast and been taken by the throat
by the labor unions; the makers have
not been treated fairly, said Mr.
Stewart. It was his judgment that the
makers provided a better boiler for
Connecticut, Rhode Island and other
States.

Mr. Stewart contended that the makers
were classed as malefactors because the
'State became hysterical over the loss of
life in the Brockton explosion, and over-
looked the fact that for twenty years
previously, less than two lives a year
were lost. He said that instead of help-
ing other States to copy its rules, Massa-
chusetts should make its own rules more
simple and more practical.

The American Boiler Manufacturers'
Association, in securing better material
and producing better workmanship has
solved the question of boiler safety,
rather than the Massachusetts rules;
rules and regulations in themselves do
not make a good boiler, said Mr. Stewart.

In answer to M. H. Broderick's pro-
posal for the Association to prepare
articles for a uniform specification. Pres-
ident Meier said that rules had been
formulated by the association as to
materials and workmanship as early as
1897 and had since been changed and
modified from time to time to suit the
requirements.

Mr. Farasey said that with the
changes made to meet the contentions
of Mr. Stewart, the makers could advise
that the specifications be generally
adopted.

John A. Stevens stated that the board
of boiler rules had sent to every repu-
table manufacturer copies of its pro-
posed rules, and that from their sug-
gestions were abstracted the best ideas.
Furthermore, the Massachusetts in-
spectors, the insurance companies and
all the boiler inspectors were asked to
contribute to the formulation; the
French, German and British boards of
trade rules were also abstracted, and it
appeared to the speakef that there was
nothing in the rules that could be mis-
understood. Mr. Stevens said that the
board had corresponded with all the
authorities known in the world, and
their replies said in plain English: "leave
the rules alone."

President Meier said that the 1898
specification was made with the under-
standing that there would be local de-
tails that would have to be settled by
local conditions. He would be glad to
see the firebar steel supersede the
flange steel.

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Miclii<^an State Convention of
the N. A. S. E.

The tenth annual State convention,
which was held at Saginaw on July 20,
21 and 22, was opened by J. D. Swart-
vout, chairman of the Board of Trade
convention committee. A prayer was
made by Reverend J. Ambrose Dunkel,
pastor of the Warren Avenue Presby-
terian church, after which Mayor Stewart,
delivered the official address of welcome
in which he assured the visitors of the
hospitality of the city and invited them to
make themselves thoroughly at home.
Response to the mayor's welcome was
made by State President Brandau. Joseph
P. Tracey. secretary of the Board of
Trade, also addressed the convention and
told of the many advantages offered by
the city as a manufacturing and residen-
tial place Fred W. Raven was then intro-
duced and spoke regarding the alms and
objects of the National Association of
Steam Engineers and gave a synopsis of
Its development since It was organized.

President Brandau, in opening the after-
noon session on Thursday, made an in-
teresting address In which he commented
upon the satisfactory condition of the or-
ganization and outlined some of the work
accomplished. He referred in compli-
mentary terms to the additions made to
Ihe state organization during the pe-
riod since the last convention was held,
the two cities coming in being Saginaw
and Coldwater.

The exhibit at the Auditorium was
one of the largest ever held at a Michigan
State convention and speaks well for the
support given by the various manufact-
urers of engineering apparatus. In con-
nection with the exhibit the Central
States Exhibitors' Association gave a
smoker Friday night at the Hotel Vincent
at which J. D. Swartwout was the presid-
ing officer. Various speakers were intro-
duced and the songs, stories and bounti-
ful refreshments were thoroughly enjoyed
by all. Contributing to the enjoyment of
those present the Elks Comedy Four
made a big hit, their quartet singing be-
ing as good as that heard on the pro-
fessional stage and their comedy parts
being of first-class order.

Officers for the ensuing year were
elected as follows: W. E. Fuller, Kala-
mazoo, president; M. Gormley, Grand
Rapids, vice-president; G. A. Turnbull,
Flint, secretary; and W. M. Moore, De-
trnlt. treasurer

To make granulated babbitt metal, melt
the babbitt in a ladle, remove the ladle
from the fire and allow the metal to cool.
When It begins to "set," stir briskly with
a stick until it has all cooled Into a
granular mass. If any particular size
of grain is desired, the metal may be
sifted, using two screens, one of the dc
sired size mesh to remove the large
grains and one slightly smaller to al-
low the escape of the fine grains.

230

POWER

August 8, 1911

Annual Convention of the

Canadian Association of

Stationary Engineers

The twenty-second annual convention
of the Canadian Association of Station-
ary Engineers was held at Stratford,
Ontario, on July 25, 26 and 27. The
Windsor Hotel was selected as head-
quarters, and the business of the con-
vention was conducted in the city hall.

The large auditorium on the main floor
of the city hall was tastefully decorated
for the use of the supplymen in showing
their goods and demonstrating their
mechanical devices. On the floor above
the delegates held their several sessions.

On Monday evening a banquet was
held at the assembl-y hall of the Grand
Trunk Railway. Robert Paterson, the
congenial toastmaster, introduced the
folowing gentlemen who responded to
toasts: "The City of Stratford," Mayor
Brown; "The C. A. S. E.," J. J. Hegg
and W. A. Crockett; "Canada," J. R.
MacDonald and H. B. Morphy; "Our
Legislature," George Torrent; "Our
Manufacturers," George McLagan;
"Association No. 31," August Kastella;
"Our E.xhibitors," John B. Cross; "Our
Guests," John A. Robertson and H.
Scrimglour; "The Ladies," Albert M.
Wickens and W. G. Walters; "The
Press," W. S. Dingham. Mr. Ranton, of
Rochester, N. Y. spoke briefly of the
National Association of Stationary En-
gineers and hoped that the Canadian
Association of Stationary Engineers
would rapidly increase. During the
evening songs, stories and recitations
were rendered by Miss Nellie May, F. G.
MacLavish, A. R. Benson, John Brandon
and Jack Armour.

On Tuesday morning the convention
was formally opened by Mayor Brown,
and responses were made for the dele-
gates by President Hegg, Secretary
Crockett, Treasurer Wickens and Con-
ductor Robertson.

On Tuesday afternoon a tour of in-
spection was made through the Grand
Trunk Railway shops and power houses.

On Wednesday afternoon, headed by
a hand of twenty-five pieces, the dele-
gates paraded to Queen's Park, where a
most enjoyable outing was held. A
ball game between the engineers and
supplymen, which was won by the latter,
started the festivities.

At eight o'clock on Wednesday even-
ing the delegates and exhibitors were
called together in the auditorium to listen
to the reading of the following instructive
papers: "Cost of Steam Powder" by J.
O. B. Latour of the Canadian Casualty
and Boiler Insurance Company; "Prob-
lems in Heating," by C. K. Dean, of the
Alberger Condenser Company; and
"The Operating Engineers' Ideal and
Its Attainments," by Peter Bain, of The
Power House. Following these discus-
sions the engineers were entertained by

the exhibitors at the Windsor Hotel.
A theater party for the ladies on Wed-
nesday evening also formed part of the
program.

At the final meeting the following
executive officers were elected and in-
stalled: William Norris, Chatham, pres-
ident; .John A. Robertson, Stratford,
vice-president; Wilson A. Crockett.
Hamilton, secretary; Albert M. Wic-
kens, Toronto, treasurer; Herman R.
Clarke, Hamilton, conductor; Samuel E.
Cosford, London, doorkeeper. Belle-
ville was chosen as the place for hold-
ing the convention in 1912.

During the convention the following
presentations were made: Retiring
president, J. J. Hegg, received a gold
past-president's jewel, the gift of the
delegates; August Kastella, chairman of
the local committee, was given a silver
mounted umbrella and W. G. Walters,
honorary chairman of the Supplymen's
Association, was also presented with a
valuable umbrella from that body.

The supplymen, at a meeting held on
Wednesday afternoon, selected the fol-
lowing officers: Earl F. Hetherington,
Goldie and McCuUoch Company, pres-
ident; J. E. Fiddes, James Morrison
Brass Manufacturing Company, first
vice-president; John B. Goff, Dart Union
Company, second vice-president; Gordon
C. Keith, Canadian Manufacturer, sec-
retary; J. N. Charles, Canadian Fair-
banks Company, assistant secretary; H.
V. Tyrrell, The Power House, treasurer;
W. R. Stavert, Jenkins Brothers, super-
intendent of exhibits; Peter Bain, The
Power House, chairman of entertain-
ment committee.

Outing of Pawtucket Associa-
tion of Stationary Engineers

The sixteenth anniversary, reunion
and field day of the Pawtucket .Associa-
tion of Stationary Engineers. Rhode
Island, No. 2, N. A. S. E. took place on
Sunday, July 30. There was the usual
big gathering of engineers and their
friends. A delegation of upwards of
thirty journeyecl from New York and
Jersey City, and there were also rep-
resentatives from Boston, Springfield,
Lowell and other nearby cities.

The party assembled at the Narra-
gansett hotel. Providence, and special
trolley cars were boarded for Palace
Gardens on Narragansett bay.

After partaking of a light lunch, out-
door sports were indulged in, the leading
feature being a baseball match, in which
a team selected from the members of
Pawtucket Association No. 2, battled
for six innings with the New York del-
egation, the former winning by the
score of 4 to 3. In the afternoon an
old-fashioned clambake was served.

In the pavilion, after dinner, there was
a vaudeville entertainment which brought
to a close a most pleasant occasion.

Chicago's New Smoke
Inspector

When the position of chief smoke in-
spector for Chicago was made vacant
by the resignation of P. P. Bird, who
accepted a position with the Common-
wealth Edison Company, Mayor Harri-
son determined to place this important
position, carrying with it a salary of
S4,000 per year, out of the realm of poli-
tical influence. Therefore, instead of fill-
ing the vacancy by direct appointment,
he appointed a commission of disinter-
ested and prominent men who were to
select a successor to Mr. Bird. After
considering the qualifications of several
eligible persons, their choice fell to
Osborn Monnett, western editor of
Power.

Mr. Monnett has had wide experience
in the power-plant field, which should
fit him to carry out his new duties with
entire satisfaction. A native of Ohio.
Mr. Monnett began his engineering career
as an oiler on Lake steamers. After
spending several years at this, he took
out a stationary engineer's license, and
held several positions in that line, finally
accepting that of chief engineer of the
Wheeling & Lake Erie Railway repair
shops. His next position was that of
chief engineer of the Rock Island re-
pair shops at Moline, 111., and he later
became associated with The Engineer.
When that paper was merged with
Power, he became a member of the lat-
ter's editorial staff, and has held the
position of western editor for the past
three years.

PERSONAL

Charles C. Moore, of C. C. Moore &
Co.. the well known firm of San Fran-
cisco consulting engineers, has been
chosen president of the Panama-Pacific
Exposition to be held in San Francisco
during 1915. The honor came to Mr.
Moore unsolicited, and with an engineer
of such wide experience at its head, the
coming world's fair promises to be a
big success.

Bearings

In a little treatise on "Bearings" is
given some forty catechetical questions
and answers on antifriction bearings
that were distributed some time ago
among a few engineers.

It is said by the publisher that the
demand for this treatise became so gen-
eral that he is induced to offer it to all
interested in its subject matter.

It is so written that the answers can
be easily comprehended by anyone. The
two types of antifriction bearings, the
ball and roller bearing, are given a clear
explanation and their uses, efficiency and
adoption are plainly set forth. The
treatise may be obtained for 10 cents
from J. A. Nelson, 11 John street, N. Y.

August 8. 1911

POWER

231

Reeves Automatic Adjustable
Valve

In Fig. 1 is shown a sectional view of
the adjustable valve which the Trenton
Engine Company has been using for
some years on its engines. This valve
has been changed slightly in that the set-
screw extends into the valve head so
that by adjusting the sleeve these

fVhat the in-
ventor and the manu -
facturer are doing to save
time and money in the en-
0ne TO om and p ower'
house. Engine room
news

Fic. I. Sectional View of Adjustable Piston- X'alve

screws are tightened up and set down
into holes drilled into the valve head,
thus preventing the sleeve from turn-
ing. There are 12 of these holes, al-
lowing an adjustment of V2 of l/IOOO of
an inch in the diameter of the valve
ring.

This valve has been found satisfac-
tory, except that in some cases the en-
gineer neglected to adjust it at inter-
vals. With these locking devices the
valve remains as adjusted.

In Fig. 2, H represents a section of
this valve which will automatically ad-
just the rings to make a tight-running
valve under all conditions.

The construction is such that the pres-
sure required to hold the valve rings
in place is not excessive, because of the
wedge-shaped cone and the friction be-
tween these surfaces. In other words,
the pressure on the piston has simply
to resist the tendency to collapse this
ring, due to compression and steam in
the cylinders after cutoff takes place.

In Fig. 2 H represents a section of
the cylinder in which the valve seat li
is shown in section; D is the valve rings.
These are made eccentric and form a
steam-tight joint with the head of the
valve at E. These rings are grooved as
shown and steam leakage past the joint
is prevented by a bronze keeper made
as shown at F. The inside of this

keeper forms a section of the ring and
the projection rides upon the wide bridge
of the port back of the ring D.

On the inner side of the ring there
is a projection which is faced off at an

angle of 00 degrees. This surface faces
against the beveled surface of the float-
ing cone which has openings through
which the hollow lugs H H pass and
which project from the valve head /.

An auxiliary piston K is fitted with a
snap ring which slides on the inner sur-
face of the lugs H H. When steam is
passing through the ports L L to the back
of the piston K. it is forced away from
the valve head / and carries the float-
ing cone G with it. The cone, owing to its
beveled outside surface, forces the ring
D out against the surface of the valve
chamber.

This construction of the valve allows
the valve ring to take its place against
the walls of the valve cage befor: the
compression forces strike the ring and
tend to collapse it.

The wear on the valve seat should be
very slight, as it is prone to wear it
round, the seat of the valve in a hori-
zontal engine being supported by the
valve stem and tail rod.

Owing to 'le peculiiir construction,
the joint bf.t ^cn the valve body and
the valve ring on the live-steam sidt will
remain tight, due to the pressure of the
cone in this direction.

This improved valve is used on the
Reeves single-cylinder and compound
engines, but it can be used for other
types of engines as well. It is the in-

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l-'(,, 2. Showing Automatic .djustinc. Piston Kings and Piston

232

POWER

August 8, 1911

vention of Clifton Reeves, vice-president
and general manager of the Trenton
Engine Company, Trenton, N. J.

Plunger Rod Grinding
Machine

The principal objects of this device are
to provide a simple and convenient means
for grinding elevator plungers as they
reciprocate.

The accompanying illustration shows
the device as applied to an elevator
plunger. It is so designed that it can
be attached to any ordinary stuffing box,
on which is mounted a two-part cylinder
secured in position as shown. This sup-
port is provided at its top with a sta-
tionary gear wheel A, concentric with
the cylinder and plunger. On this sup-
port is also fixed a bracket in which is
journaled a shaft that receives power
from a motor or any other desired source
•of power.

This shaft is connected by beveled
gears to another shaft journaled in the
bracket on which is fixed a pinion mesh-
ing with the bottom rotable gear B of
the same size as the stationary gear A

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Pi.UNCER-ROD Grinding Machine

and concentric therewith. This gear is
mounted on the split support and has
a babbitt bearing. Movable with this
gear and fixed to it are two brackets C,
each carrying two grinding wheels on two
different carriages. The wheels are at
the top of the vertical shafts. On the
lower ends of the shafts are two pul-
leys connected by a belt which is covered
with emery and is used for polishing.

The adjustment for setting the grind-
ing wheels against or out from the
plunger is done automatically with a
wheel arrangement without stopping the
machine.

The operation of the device is as fol-
lows: The parts having been mounted
on the cylinder stuffing box and the
driven pulley connected with the motor
or other source of power, the rotation
of the pulley obviously will cause the
gear B to rotate, carrying with it the
bracket C C. This bracket carries a pinion
always in mesh with the gear A and

causes this pinion to turn on its own
axis. This rotates the grinding wheels
as it travels around the cylinder guides.

The grinding wheels w'ill follow the
slight inaccuracies of the plunger to a
certain extent, but the object is to grind
it smooth rather than to a true cylindrical
surface.

It is said that a plunger ground in
this way will operate efficiently and not
cut the packing in the stuffing box.

This device is the invention of A. P.
Klingloff, 28 Kittredge street, Roslin-
dale, Mass.

Uehling Draft Recording

Gage

The Uehling draft recorder was de-
signed to record accurately differences
in vacuum below 0.10 of an inch of water.

Fig. 1. Uehling Draft-recording Gage

Fig. 1 shows a front and Fig. 2 a sec-
tional view of this gage.

It consists of a case containing a
clockw^ork T, Fig. 2, which drives a disk
E upon which is mounted a circular
sheet of recording paper. Directly under
this case is mounted a cylindrical vessel
A containing oil. Concentric with this
vessel is placed a tuoe K containing mer-
cury M, as shown. The bell B which
is sealed by the oil O is buoyed up by
the float F on the stem S which is im-
mersed in the mercury. The pen P is
supported and moved directly by the bell
by means of the elastic arm R. A pipe G
comm-jnicates with the sealed chamber
formed by the bell.

If suction or draft is applied to G
the bell descends until it is balanced
by the mercury displaced during the
descending of the stem S^ the diameter
of which is so proportioned as to give
the desired range.

A record on a chart of 2-inch range
can be read to 0.025 inch, while records
made on a chart of 1-inch range can be
read accurately to 0.01 inch of water

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Fig. 2. Sectional View of the Gage

column. The charts are standard, but
the recorder is applicable to recording
very light pressures as well as draft.

This draft recorder has no spring or
multiplying lever to get out of adjust-
ment or calibration, and it is simple in
construction, accurate and reliable. It
is made oy the Uehling Instrument Com-
pany, Passaic, N. J.

\"..!. M

NKW YORK, AUGLST 15, 1911

No. 7

T

HE following is a message to the fire-
man :

Successful firing simply means the produc-
tion of the largest amount of steam at a
uniform pressure with the least amount of
fuel and labor.

To be a successful fireman, a man must
use intelligence. He cannot follow any fixed
set of rules, do as his grandfather did or as
he has been taught. He must study the
plant conditions, the weather, load and
fuel. What did nicely yesterday may not
answer "at all today. What produced good
results in a former plant may not work at all
well in the present one. Methods which the
other fellow finds successful may not suit
your own case even a little bit.

Whether to carr\- thick fires or thin; the
matter of draft regulation; the amount of
forcing necessary; the selection of the projxr
time to slice or clean fires; the size, kind and
quality of coal to be used, all these should
be left to the man on the job and they may
be if he is of the right kind.

The man who is continually working at
his fires, poking, leveling and stirring, can-
not produce economical results.

First, study the conditions and then learn
how to fire to suit those conditions. Stoke
coal onto one side ot the fire at a time if
possible; stoke lightly and do not smother
the fire; watch the results. T^se vour head

more and the firmg tools less; the use of the
coal scoop is a fine art.

Mr. Fireman, you are at work at a trade.
If you make good you are the man wanted;
if not, some other man must take your place.

Remember, a good fireman is a valuable
man in any steam plant. In the fire room
you can lay the foundation for becoming a
successful engineer or qualifying for other
responsible positions. Make the most of
your chances by carefully studying the needs
of your work.

More boilers, arches and grates are ruined
by poor management than by actual service.
The fireman who first has an extremely hot
and then a dead fire; first, the dampers wide
open, then tightly closed; water up, then
down; who shovels the coal in anv old wav,
pokes, digs and levels the fires continually
and then brags about how much coal he can
handle, need not reasonablv expect to ad-
vance or even hold his job for long.

The mechanical stoker is designed to do
automatically and at the projx'r time what
the human stoker sometimes neglects. The
man may sit and read mitil his fires bum
down, so that when he does get ready to
work he has to rush the fires so as to get
back what he wilfully lost. In other words,
he uselessly burns up his emplover's money.
At least, the automatic stoker has not this
failing. Oftentimes, the very man who is
thus neglectful complains the loudest for not
being paid more or advanced.

234

POWER

August 15. 1911

Remodeled Substation at Reading

This substation was briefly mentioned
in connection with the description of
the new power house which appeared
in the November 22, 1910, issue.

At the time of the construction of the
new power plant at the outskirts of the
city, the old plant consisted of three
buildings on Seventh street, in the heart
of the city, containing the engines and
generators, switchboards and regulators,
.with a large building in the rear, extend-
ing to Lemon street, which contained
the boilers. A plan of these is shown
in Fig. 1. Building No. 1, the first to
be erected, was equipped with six small
horizontal, high-speed engines located
on the first floor, each belted to two
small dynamos on the second floor.
There was also a line of shafting on
the first floor driving two rows of dyna-
mos and arc machines on the second
floor, this line shafting being driven by
a 700-horsepower Hamilton-Corliss en-
gine, located in an adjoining structure.

At this stage the equipment totalled
fourteen 60-kilowatt. 125-volt Edison bi-
polar machines, eighteen arc dynamos,

]\'ilh the completion of the
new plant of the Metropoli-
tan Electric Company at
Reading, the old generating
station, containing a great
variety of apparatus, was
converted into the main sub-
station of the system. This
necessitated completely re-
modeling the buildings and
suhstitiding entirely new
equipment, at the same time
keeping the station in ope-
ration.

six small engines and one Corliss en-
gine, supplying the Edison three-wire
system and arc circuits. Switch-
boards for the entire Edison three-wire
system and generators, series arc sys-

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tern and series incandescent system were
also located on the second floor.

In an extension at the rear a 350-
horsepower Green Corliss engine was
added, belted through a jack-shaft to
a 2300-volt, 60-cycIe, two-phase alter-
nator. The switchboard for this unit
was located near the eni of the jack-
shaft, this being the first move toward
high tension.

In 1894 building No. 2 was erected,
in which were installed three vertical
cross-compound engines, direct con-
nected to railway generators of a total
capacity of 1600 kilowatts, a vertical
cross-compound engine direct connected
to two 100-kilowatt, 125-volt direct-con-
nected machines, and the railway switch-
board.

Further growth was represented by
the erection of building No. 3, containing
at first two Ide engines, one belted to
a Short railway generator and a West-
inghouse 2300-volt, 60-cycle, 2-phase
generator, the other belted to a Jenney
multipolar generator and a Thompson-
Houston railway generator. Later, there
were installed three direct-connected
units, an AUis-Chalmers cross-com-
compound engine driving a 500-kilowatt
railway generator and two Harrisburg
cross-compound engines, one coupled
direct to a 350-kilowatt, 2400-volt Stan-
ley alternator, the other to two 300-
kilowatt, 125-volt direct-connected gen-
erators.

Other additions were, three boosters
and a railway battery, and two 400-kilo-
watt, 25-cycle Stanley rotary converters,
supplying current to two 300-kilowatt

Fig. 1. Plan of Buildings Before Remodeling

August 15, 1911

substations through step-up transfor-
mers and a I5.000-volt transmission line.
The final rated capacity of this plant
was 7800 boiler horsepower, and 5000-
kilowatt generator capacity. Figs. 2, 3,
4 and 5 are views of this old equipment.

Reconstruction for Use as a Sub-
station

When the new power hoirse was built
last year it was decided to convert the
old plant into a substation. The first
undertaking was the remodeling of
building No. 1 without interrupting the
operation of the apparatus. It was pos-
sible to put in a single row of steel col-

POWER

moved, and a concrete slab roof sup-
ported by steel trusses erected.

The structures on the side and rear
end, which contained, respectively, the
step-up transformers and the Green-
Corliss engine, were torn ' down, giving
more yard room for the pole lines, and
improving the appearance of the prop-
erty.

To give space necessar>' for the new
equipment in No. 2 building, an addi-
tion was made, extending into the old
boiler house, the rear end wall being
moved back. The rearranged plant has
50 per cent, greater capacity, and occu-
pies only 41 per cent, of the ground

235

which the air-blast transformers were
placed. In order to install the fiber
conduits connecting the transformers
and rotaries to the high-tension switch-
ing systems, it was necessary to raise
the floor levels of both buildings suffi-
ciently to permit these conduits to be
laid on the top of the old engine-room
floor, and this resulted in the switch
cell compartment floor being higher
than the rest of the floor in No. 1 build-
ing, as shown in Fig. 9.

New Installations

The substation receives high-tension,
three-phase, 60-cycle currents at 13,200

Figs. 2, 3, 4 and 5, Showing Old Equipment

umns down the middle, which would
support steel floor beams laid above the
old wooden floors, so that the old floors
would serve as forms for the new con-
crete floors. The machines were raised
to the new level one at a time; the belts
were lengthened and the belt holes left
In the new concrete floor to be closed up
after the removal of all the old appar-
atus. The third floor being built, fur-
nished protection to the apparatus so
that the old wooden roof could be re-

space taken up by the original plant.
The general arrangement of the re-
modeled plant is shown in Fig. 7.

In both No. 1 and No. 2 buildings,
the ground floors were practically a solid
mass of concrete foundations for the
engines, shafting and generators which
had been installed from time to time.
Along the walls, however, there were
trenches for steam pipes which, with
a slight amount of additional work,
could be used for the air tunnels over

volts, through underground cables from
the new generating station. Provision
is made for connection to six of these
cables and six high-tension switches
were accordingly installed, four for
present use and two for future needs.
Current is distributed by this substation
for railway feeders at 600 volts; for
an Edison three-wire system at 125 and
250 volts; power circuits at 60 cycles,
three-phase, 2300 volts; to lighting cir-
cuits at 2300 volts, 60 cycles, single

236

POWER

August 15, 1911

phase;, and to series mercury arc and rotary room floor. The benchboard con- however, either set of busbars can carry

series tungsten street lighting systems, trols all of the high-tension switches either the lighting or power feeders, or

The rated capacity w'ith the present which are located on the first floor, and both, and any transformer can supply

installation is 8000 kilowatts, and pro- the 2300-voIt switches located on the either set of busbars, or both. The

vision is made for a future installation second floor for the control of the low- switchboard for the Edison three-wire

Railway Rotary Converters

Fig. 8. Arc-control System

amounting to 3000 kilowatts, making the
ultimate rated capacity 11,000 kilowatts.

Building No. I

As rearranged (see Fig. 9), the first
floor of the building contains the high-
tension switches and busbars, office of
the engineer in charge, and the arc
lamp and meter repair department. The
second floor contains the 2300-volt

tension side of the light and power
transformers. The switchboard for the
2300-volt light and power systems is
a vertical board controllirig all the out-
going 2300-volt lighting and power cir-
cuits. These switches are remote-con-
trol solenoid-operated, and are arranged
in two banks, over each bank being lo-
cated a set of three busbars. Normally,
one busbar set is to be used for three-

system is composed of rotary converter
control panels and feeder panels. The
same arrangement is carried out in the
railway switchboard. These three boards
are arranged in one line facing the
benchboard (see Fig. 10), so that ever>'-
thing on these boards is in full view and
within easy reach of the operator.

Building No. 2

This building contains the railway
rotary converters and transformers, light-
ing rotary converters, transformers and
regulators, 2300-volt light and power
transformers, blowers for cooling these
transformers and regulators, the tung-
sten and arc regulators and switch-
boards. Underneath the switchboards

Fig. 7. Plan of Present Substation

switches, and all of the switchboards phase power feeders, and the other for for the arc and tungsten systems is

except those used for the street-lighting the single-phase lighting feeders, a tunnel which contains the 13,2(X)-volt

system. The benchboard is located in connected to separate transformers, so busbars supplying these systems, and in

front of an opening in the wall, which that the irregular motor loads cannot compartments are the oil switches, which

gives the operator a full view or the affect the lighting. In case of trouble, are operated by rods carried up through

August 15, 1911

POWER

237

the floor to the back of the panels. This
is shown in Fig. 10.

HlCH-TENSION

Switches
System

The high-tension switches are con-
nected to a main busbar which is in

All the rotary converters are started
from the alternating-current side,
through low-voltage taps, without re-
actances. They are provided with speed
governors, those supplying the lighting
circuits being regulated on the alternat-
ing-current side by six-phase induction

Test of Large Boilers

The large double Stirling boilers at the
Delray station of the Edison Company
at Detroit have been tested, and it is
said that the results are very interest-
ing. The boilers were described in the

Section ■■
Fig. 9. Section through Substation Shoeing New Arrangement

three sections, and an auxiliary busbar

Ji is in two sections. By this means,

the use of two busbar section

Jies", it is possible to isolate any line

!i is carrying a badly fluctuating

.; and, if necessary, this line may be

J isolated back to the main busbar in the

generating station, or still further, by

means of the auxiliary busbar to one

generating unit in the main station.

Two auxiliary switches are provided,
which will, by means of the auxiliary
busbar, replace any regular switch which
may be out of commission, thus doing
away with the necessity of providing
duplicate feeder and transformer
switches. This saved space and first
cost.

Outgoing Lines

At present the railway, lighting and
power feeders are taken out of the side
of building No. I, and the street light-
ing circuits out of the Lemon street end
of building No. 2, all overhead.

The railway ground enters with the
high-tension underground conduits at
the front of building No. 1, where it
is connected to a busbar in a manhole
under the floor, the negative of each
railway rotary converter being con-
nected to the ground busbar.

The neutral for the Edison three-
wire system is connected to a busbar in
he tunnel. From here, separate cables
ire connected to the low-tension side
>f the lighting rotary transformers by
means of switches on the starting panels.
Only the positive and negative leads
ire carried to the distributing switch-
Joard on the second floor.

type, air-blast, motor-operated regula-
tors, controlled from the sw'itchboard
gallery.

The series mercury arc and tungsten
circuits are regulated by air-cooled con-
stant-current transformers, in which the
movable coils are balanced by weights.

issue of October 1 1 of last year. Each
contains upward of 23,0(K) square feet
of heating surface, and some 480
square feet of grate surface. The par-
ticulars of the test are not available for
publication, as the Babcock & Wilcox
Company, tlic makers of the boiler, are

V^X

Fig. 10. CoNTRoi Switchboaro in Gallery

The design of the electrical equipment
and the architectural and structural
changes was done by >X'alfer .[. Jones,
consulting engineer, of New York City,
who also designed the main generating
station.

reserving them for presentation to a
future meeting of the American Society
of Mechanical Engineers, but it is
understood among Detroit engineers that
5.SO0 horsepower was obtained from a
single unit.

238

POWER

August 15. 1911

Draft and Differential Gages

There are three units commonly used
in the measurement of fluid pressure:
pounds per square inch, inches of mer-
cury and inches or feet of water. Steam
pressure is measured in pounds per
square inch, back pressure or vacuum in
inches of mercury, draft in inches of
water and water pressures in pounds per
square inch or in feet of head. As a
rule, the pressure of the atmosphere
(14.7 pounds per square inch) is se-
lected as the point from which measure-
ments are made, the ordinary pressure
gage reading so many pounds above at-
mospheric pressure, the vacuum gage so
many inches of mercury below it and
the draft gage inches of water above or
below the atmosphere. In some cases
merely the difference between two pres-
sures is required, for which purpose a
difierential gage is used.

The conception of pressure in pounds
to the square inch needs no comment.
A cubic inch of water at 60 degrees Fah-
renheit weighs about 0.036 pound; hence,
a column of water 1 inch high and 1
square inch in cross-section will exert a
pressure by its weight of 0.036 pound
distributed over the square inch of its
bottom surface of contact. If the col-
umn is made 2 inches high, this pres-
sure is doubled, and so on.

Mercury, at 60 degrees Fahrenheit,
weighs nearly 13.6 times as much as
water; therefore each inch of mercury
exerts a pressure of
13.6 X 0.036 — 0.49 pound per square
inch

The simplest form of draft gage, the
U-tube, is that shown in Fig. 1. This is
a piece of glass tube bent in the form
of a U and partly filled with water. It is
connected to the flue at -4 by a rubber
tube, and when the two water levels are
the same the pressure in the flue is the
same as that without. But if the level
on the flue side of the U-tube is H inches
higher than the other, then the pressure
of the atmosphere on the open side of
the tube is enough greater than the flue
pressure to raise the weight of H inches
of water against it. From this difference
in level the difference in pressure is ob-
tained between that in the flue and at-
mospheric pressure expressed in inches
of water.

Such an instrument is easily made and
can be put together at small cost. It is
not always easy to bend the glass into
the form of a U, in which case two
straight pieces of glass may be joined
by a piece of rubber tubing, as shown
in Fig. 2. These may be mounted on a
board to which a paper scale is glued
and afterward varnished.

The simple U-tube is applicable also
to pressures greater as well as less than
atmospheric, the high level then being
on the open side. For measuring pres-

By Julian C. Smallwood^

The various types of draft
and differential gages in
general use are described
and their salient features
pointed out.

•-Associate professor of experimental engin-
eeiing, Syracuse University.

sures of more than one pound, however,
the water gage becomes inconveniently
long. Hence, for this purpose a heavier
liquid, such as mercury, which will not
rise so high, is used. Each inch of mer-
cury being equivalent to 0.49 pound per
square inch, indicates a pressure 13.6
times as great as that shown by water.

The scales of these gages are gradu-
ated in various ways. Some have an
ordinary scale, as in Fig. 2, which re-
quires the hight of both levels to be read
and then the lower subtracted from the
upper to obtain the difference in level.
Others are graduated as shown by Fig. 3,
the purpose being to avoid two readings.
A U-tube supplied with this scale must
be filled until the level on both sides is
at the zero graduation. Either the upper
or the lower scale is read and the reading
is doubled to obtain the inches of water.
If any of the water is evaporated or
otherwise accidentally lost, however, the
reading will be inaccurate.

Another form of scale is shown by
Fig. 4, which obviates doubling the read-
ing. This may be made adjustable
through a small range so that its zero
may be readily brought to coincide with
the no-pressure position of the water level.

A gage giving direct readings may be
made as shown in Fig. 5. This consists
of a cup C of comparatively large diam-
eter, containing liquid in which a glass
tube of small bore is placed. As
the liquid rises in the tube the
level in the cup sinks, but on account
of the large area of the liquid in the
cup its level does not sink appreciably.
Thus, if the cup is 2 inches in diameter
and the tube J-jS-inch bore, for each inch
the level in the tube rises that in the
cup falls 1/256 inch. If the gage range
is 5 inches, the total fall of level in the
cup is about 1 '50 inch, which in this
case is negligible. If the cup is a closed
chamber except for a tube leading into
its air space, the instrument may be used
as a differential gage.

It is on the principle of this gage that
the mercury barometer is made, the form
of the instrument being like Fig. 5 except
that the glass tube is closed at the top
and air excluded, as in Fig. 6. This is

an absolute-pressure gage as distin-
guished from a differential gage, the ab-
solute pressure of the atmosphere being
recorded by the hight of the mercury
column, as there is no other force in the
tube than that due to the weight of mer-
cury. A thumbscrew D is arranged to
adjust the level in the open vessel at a
fixed hight shown by the point £.

The simple U-tube may be used to
show the difference of pressure in two
parts of a closed pipe by connecting its
two sides, one to each part, as shown by
Fig. 7, instead of leaving one side open
to the atmosphere. ^X'hen measuring
forced draft it should be connected in
this way, one side to the ashpit, the other
to the chimney flue. The pressure in the
ashpit is greater than that of the at-
mosphere; that above the fuel bed may
be less.

In some appliances for measuring the
flow of steam the U-tube may be used,
its form being somewhat different for
practical purposes. When mercury is
employed water of condensation settles
on one side of the mercury column and
influences the reading. This may be cor-
rected as follows: Considering Fig. 8,
the true difference of pressure is

13.6
inches of mercury; that is, the water
column in inches is divided by 13.6 to
obtain the additional pressure in inches
of mercury. If the water were on the
other side it would be subtracted.

As applied to furnace drafts, the U-
tube as described is not satisfactory be-
cause ordinarily, with natural draft, the
difference does not exceed a few tenths
of an inch. Therefore the instrument is
difficult to read closely and does not indi-
cate small changes of draft. To over-
come this difficulty a great many in-
genious devices have been constructed.

It would appear at first that the diffi-
culty could be overcome by employing
a liquid lighter than water. It is not
practicable, however, to obtain one
enough lighter to magnify the difference
of level sufficiently, but two liquids, dif-
fering from each other in density, will
answer the purpose. Thus in Fig. 9 as-
sume the upper liquid to be oil whose
specific gravity is 0.9 and the lower liquid
water. If the levels in the cups FF are
the same, then there is a difference of
pressure corresponding to the difference
in the weights of the column H of oil
and water. Above // the columns of oil,
being of equal hight, balance each other;
below J J the water columns also balance.
Between / / and / / there is a column of
water acting against the flue pressure
and one of oil, equal in hight. acting with
the flue pressure. .As the pressure of the
oil is 0.9 that of the same hight of water
the draft is equal to {H — 0.9 H) or 0.1 H

August 15, 1911

POWER

239

Fi9 19 f«3Z\

VARrous FoRws OF Gages

240

POWER

August 15, 1911

inch of water; that is, the draft in inches
of water is one-tenth of the reading. In
general, calling the specific gravity of the
oil S and /; the draft in inches of water,
h ^ (\ — S) H

If the heavier liquid is not water and
has a specific gravity Si, then
/z = (S, — S) H

By choosing the liquids for such a
gage of nearly the same densities, any
desired range may be obtained for the
measurement of a small difference of
pressure. The more nearly equal in
weight they are the greater the motion
of the liquid for a given draft. In gen-
eral, the number of inches of rise in the

ordinary U-tube is multiplied by ^g — 3-^-

In practice, when used as a draft
gage, the difference of level in the cups
FF would alter the foregoing relation.
To keep the cup levels the same a cross-
connection with a cock K joins the tops
of the tubes. Another cock L is placed
at the bottom of the tubes. When in use
K is closed first and L opened; when the
oil stops rising in the right-hand tube, L
is shut and K opened and the flue con-
nection is removed. This allows the oil
in the cups to come to the same level
again without disturbing the levels in the
tubes. The cocks are then reversed until
the oil has risen again as high as it will,
and the level in the cups is adjusted once
more. This is repeated until the oil no
longer rises, upon which the reading is
taken. This is the principle of Hoadley's
draft gage.

The draft gage shown in Fig. 10 con-
sists of two cups, one closed, the other
open to the atmosphere. They are con-
nected below the water line by a hori-
zontal tube of small bore containing
water in which there is a small air
bubble. The motion of this bubble is a
measure of the draft. As the water
rises in the right-hand cup the bubble
moves to the right a distance propor-
tional to the difference of level in the
cups. By making the ratio of cross-
sectional areas of the cup and the tube
bore the required amount, any desired
range of motion may be obtained, the
motion being inversely proportional to
the ratio of areas.

Although the writer has never used
this form of draft gage, he believes it
would be unreliable on account of the
possibility of the bubble changing its
position in the tube irrespective of the
draft. As the bubble moves toward the
right the water which wets the wall of the
tube tends to remain stationary. This ob-
jection could be overcome by using mer-
cury instead of water, in which case,
hovi'ever, it would be necessary to make
the ratio of cross-sectional areas very
much greater for a desired motion of the
bubble.

Fig. 11 shows how this form of gage
may be easily made from two bottles

with perforated corks together with glass
and rubber tubing.

A draft gage designed by Professor
Kent is shown by Fig. 12. It is made
of two tin vessels M and N, the former
inverted and suspended within the other
by a spring. Its interior is subjected to
flue pressure through the tube O. The
pressure of the atmosphere being greater
tends to push down the suspended can.
This tendency is opposed by the spring
and, according to its extension recorded
by the pointer P, the draft is measured.
The equation of the instrument, neglect-
ing buoyancy, is

p V a — 0.036 h X a — n X H

from which,

h= "^^
0.036 X a

where,

p = Difference between flue and at-
mospheric pressures i n
pounds per square inch;

a = Interna! cross-section, in square
inches, of can M;

n =r Number of pounds correspond-
ing to 1 inch extension of
spring;

H = Extension of spring in inches
corresponding to p X a
pounds;

h = Draft in inches of water;

0.036 a'

The equation {h — k H) shows that
to obtain the draft the reading on the
scale is multiplied by a constant which
is less than one. The increasing buoy-
ancy as AI sinks is negligible if the de-
sign of the gage is good. This instru-
ment does not quickly respond to changes
of draft, however, and is cumbersome.

Fig. 13 shows Miller's draft gage in
which the difference of level is not mag-
nified, but a very precise instrument,
the hook gage attached to a micrometer,
is used to measure the level.

Perhaps the simplest and most satis-
factory form of draft gage is the varia-
tion of the ordinary U-tube shown by
Fig. 14. It is set on a slant so that a
vertical difference of h inches between
the water levels causes an actual motion
of H inches. By varying the slant any
desired magnification may be obtained.
This is generally made with a scale on
the principle illustrated in Fig. 4 so that
only one reading need be taken. It may
be readily constructed of a piece of gage
glass Q (Fig. 15) and a glass tube R
together with some rubber tubing; per-
forated corks S may be used if forced
draft is to be measured. The gage
should be mounted on a board to which
a spirit level T is attached so that the
slant of R may be kept as intended.

For the purpose of making this gage
more compact the slanting tube is some-
times in the form of a helix.

Most of the previously described gages
are applicable to the measurement of
water as well as gas pressure, the liquid
used in them for this purpose being mer-
cury or oil. Fig. 16, for example, shows
the ordinary U-tube inverted for use with
oil. The interpretation of the reading
is the same as explained for the Hoadley
gage. It is important to exclude air
bubbles from the piping system of such
a gage, and this can be done by care-
fully introducing the oil or mercury
through cocks. A column of air in the
connections on either side would cause
a reduction of weight which would be
balanced only by a variation of the true
level difference of the gaging liquid.

Fig. 17 shows a gage using mercury
for large differences of pressure. One-
eighth-inch pipe and fittings are used
and the long gage glasses U U are joined
by a cast-iron well W. The pots V V
are arranged to catch the mercury should
the pressure become sufficiently great
to blow it beyond the gage glasses. The
cocks are arranged for introducing the
mercury and excluding the air. In the
right-hand column there is acting a
weight of H inches of mercury which is
partly balanced by the same hight of
water on the other side. The mercury
column causes a pressure of 13.6 W
inches of water; therefore the pressure
difference indicated by the gage is

13.6 H — H = 12.6 H inches of water

or 1.05 H feet. That is, to interpret the
reading of this gage its reading in inches
must be multiplied by 1.05 to get the
difference of pressure head in feet.

Applications of the Differential
Gage

In Fig. IS the symbols P, V and A
stand for pressure head in feet, velocity
and area in square feet respectively at
the two sections of the pipe. Since the
sections at A, and A^ are different, the
velocities will be different, V^ being as
many times F, as A, is times A^. Neg-
lecting the losses due to friction, etc.,
the total energy of the water in the one
section is equal to that in the other, this
energy being in two forms, pressure and
velocity. Since the velocity in the small
pipe is greater than that in the large, the
pressure in the latter must be less and
the diminution in pressure energy must
equal the gain in kinetic energy. There-
fore, the difference of pressure in the
two pipes is a measure of the velocity
and consequently the quantity, according
to the following relation:

0 =

A, X A

J^y ,g(P,-P.J

I Ai-Ai

in which Q is the quantity flowing in
cubic feet per second and g is the ac-
celeration due to gravity, 32.16. This is
the principle of the venturi meter, a very
precise instrument for the measurement
of the flow of water. It has also been

August 15, 1911

P O \(' E R

241

applied to steam and perfect gases but
with less success. Fig. 19 shows the
usual proportions of the meter, the actual
discharge being between 95 and 99 per
cent, of that shown by the formula.

Fig. 20 represents a Pitot tube, an-
other instrument for measuring velocities
and quantities. It is a tube having a
quarter bend, set facing the direction of
flow. The hight H of the liquid in the
tube is a measure of the velocity or

V= ] 2 gli

h being the head in feet of whatever
liquid or gas is flowing. To convert the
reading H to the equivalent head of the
fluid whose velocity is being measured,
it is necessary to multiply by the ratio
of the densities of the gaging and the
measured fluids. Thus, if the gaging
liquid were 10 times as heavy as the
fluid being measured, h would equal 10 H.
In general,

V= J 2 gCH

in which C is the ratio of densities.

The Pitot tube has been used largely
for velocity measurements in open
streams, but not until comparatively re-
cent years has it been applied extensively
to the flow of liquids and gases in closed
pipes. Fig. 21 shows its arrangement
for this purpose. Since in such a sys-
tem pressure is recorded as well as
velocity, a pressure tube is added. Static
pressure only acts through this tube and
balances the static pressure in the other
tube; hence the gaging liquid records the
velocity head only.

The simplicity of this device is allur-
ing, but it should be used with caution
in careful measurements as a great many
possible conditions may cause inaccura-
cies. The velocity of the fluid varies
across the pipe section and the velocity
tube must be placed at the point of mean
velocity. The fluid sweeping past the
pressure tube tends to make a suction
reducing the effective pressure in it. If
there are eddies in the current these al-
so tend to distort the record. The gag-
ing generally should be made in a clear,
straight stretch of pipe where there is
nothing to disturb the uniform passage
of the fluid.

When used for the flow of water with
mercury as the gaging fluid

V -. Hi, I H

and for the flow of air at atmospheric
pressure and 60 degrees Fahrenheit,
water being the gaging fluid,

1 — r>6 , I 77

■in which V is the velocity in feet per
second and H the reading in inches.

The gages described are useful in
measuring losses of pressure in various
parts of blower systems. By their use
leaks may often be located and other-
wise unsuspected losses remedied.

Practical Hints

The level of mercury in a glass tube
curves from the center downward, while
that of water cur\es upward. It is best
to read the hight on a horizontal line
tangent to the curve, as Z Z, Fig. 22. In
the inclined-tube form of gage, if the
tube is about !< inch in diameter, the
level takes a curve as shown, which
is very conveniently read at Z. The
bore of the tube used should not be too
small as capillary action may cause
error.

When oil is used as a gaging fluid its
specific gravity may be found as shown
by Fig. 23. A little oil is floated on
water in one side of a U-tube and its
hight H, and that of the column of water
balancing it H~. are measured. Then the

specific gravity of the oil is 77^.

Considering the units of pressure
measurement dealt with, it is unfortunate
and illogical that three different physical
quantities and two starting points for
measuring are employed when one would
do. There is no reason why the ordinary
spring-pressure gage should not be grad-
uated in pounds above a perfect vacuum
and its units used for whatever pressures
are measured. U-tube scales, no matter
what their liquid, could be graduated to
read directly in pounds per square inch
quite as conveniently as the present sys-
tem of inches. It may be contended that
for drafts and small pressure differences
the pound is too large a unit. This could
be remedied by using one one-hundredth
of a pound as the unit for small pres-
sures. There would then be 3.6 of these
units to an inch of water.

Cost of Power in an Office
Huilding Plant

By a. L. S\xeet?er

Many office buildings in our large
cities have a daily population of 500 to
2000 people and in order to supply their
requirements in the way of light, heat,
air, water, transportation and toilet privi-
leges a power plant is necessary.

Such a plant mav be said to be the
very heart and lungs of the building and
upon its efficiency depends to a great ex-
tent the rsntal of the numerous offices.

Recently the author was requested to
examine such a plant for some clients.
Ihe tcsults of this investigation may be
of intetest.

The building was a 10-story structure,
of brick and steel, containing 100,000
square feet of rentable floor space.

The boiler plant consisted of three
horizontal water-tube boilers rated at
150 horsepower each; the furnaces were
equipped with mechanical stokers, and
the average hnrscpoivcr developed hy Ihe
boilers was 196, on an evaporation of
7.09 pounds of water per ton of coal.

Three engines of the simple, high-
speed automatic type were each con-
nected to 100-kilowatt direct-current gen-
erators supplying electrical energy for
the elevator service, lights and motor
fans in the various offices throughout
the summer months.

During the day the average electrical
horsepower shown at the switchboard
was S9, the indicated horsepower was
110, and the efficiency, therefore, 80.9
per cent.

The remaining equipment consisted of
three feed pumps tor the boilers, two
service pumps to supply water to the
upper part of the building and one 5-
horsepower ammonia ice machine for
cooling the drinking water. A vacuum
system using the exhaust steam from
these I'nits heated the building.

There were three Otis electric ele-
vators which made an average of 10(X)
trips per day and carried approximately
2790 passengers. The power required to
operate these elevntors was 17.6 per
cent, of the total amount generated.
From records it was shown that the aver-
age steam consumption of the generator
engines amounted to 107 horsepower.
The remaining horsepower was divided
among the feed and service pumps, the
vacuum system, the refrigerating plant,
etc., as given in the following table:

nt.-^TIUIUTlON OF POWER

Avt raqe horsepowtTKeneraleil by boilers 196

.-Vvt-race horsepower consumed by
engines 107

.\veraee horsepower consumed by vacu-
um pumps 16

A V race horsepower consumed by feed
pumps 23

AviraRe horsepower consumed by ser-
vice pumps 6

AviTace horsepower consumed by refri-
gcrat ine plant 5

Avi>raee horsepower consumed by ele-
vators 17.

Averaee horsepower consumed by lights
anil fans

2 1 . S.i
196
COST OF ELKVATOR .SERVICE PER MONTH

Total.

Cost of power .
One slarliT , , ,
Threr oprrators
Maintenance

S9.5.2.5

60 00

150.00

5.00

Total $,)10 25

Cost per dav 10 37

Cost per trip 0 OlO.t?

The following tables give the monthly
cost of power and the total cost for the
building:

MONTHLY I O.ST OK POWER

( 'osl of coal $476

Chief engineer 120

Two assistants 100

Two flrcnien 100

( Ine oiler .... !.'•

Reiialrs . . '<<S

Total S«B7

Cost per lioiler horsepower per month S4 57
Cost per boiler horsepower per day 0 152

TOT\L Cf)ST n|- POWER FOR THE
lit IIJU.SC,

Cost per month ««n7 00

c..»l |H-r dav 26 .W

Cost |ier venr n.SiW.SO

KonlaM" floor spacp, 100.000 •qiian* feet.
Coal of iH'wnr i>er s>|iiare fool of space

p.r v.ar O OS

^ I atlv if>«l of elevator s«rTi«e 4.22« 70

T ilnl m»l with elevator MTl-W* I3.»<?n 20

Tnifll ropt per sqiian' fo<tt of ^fare p<»r

year 0.138

242

POWER

August 15, 191 1

Inertia of Air Compressor Intake

That the inertia of the pulsations of air
entering a compressor cylinder, due to
the reciprocating action of the piston,
may cause an increase in the pressure of
the air at the end of the suction stroke,
appreciably above atmosphere, thereby
increasing the volumetric efficiency of the
cylinder, is a subject of considerable dis-
cussion among pneumatic engineers. Fig.
1 shows an air-compressor indicator dia-
gram with this rise in intake pressure
above the atmospheric line at the end of
the suction strokes, A A; such diagrams
often being found and by some mis-
takenly regarded as evidence of dis-
charge-valve leakage.

It is quite generally admitted that, un-
der favorable conditions of unobstructed
piping, high piston speed and relatively
large number of reciprocations, a water
pump actually will deliver more water
than its piston displacement would indi-
cate. This is simply because the water
attaining a high intake velocity, does not
stop instantly when the piston reaches
the end of its travel, but the inertia of the
moving water tends to continue the flow
during the instant of rest previous to re-
versal of piston stroke.

This sounds like "perpetual motion,"
but an instant's reflection will free the
mind of such an impression. The speed
and inertia given to the rapidly moving
water must, of course, have come from
the piston and this latter must have re-
ceived them from the power of the driv-
ing mechanism, so that every extra foot-
gallon of work done will be accounted
for at the motor end of the machine.

Such conditions in a water pump could
obtain only with relatively low heads be-
cause, water being incompressible, the
energy of flow quickly would be absorbed
in overcoming the pumping head as the
water rushed directly through the pump
cylinder into the discharge. This restric-
tion would not hold, however, with mov-
ing air, for, although the air is very much
lighter and has much less inertia for a
given volume, even at its higher speed,
this inrushing air would not encounter
the pressure of the discharge at all; but
simply would crowd into the cylinder
against a pressure approximately atmos-
pheric, causing a slight increase of this
pressure above the atmospheric line, as
shown in Fig. 1.

If the inertia effect does take place, as
the rise in the air-intake line would seem
to show, to marked degree sometimes,
what effect does it have, and can any
practical steps be taken to improve the
action of a compressor thereby? The ef-
fect of an increase in the pressure of the
air just as the compression stroke com-
mences, is materially to increase the vol-
umetric efficiency of the cylinder; that is,
tn increase the amount of air compressed
by a givefl sized cylinder. In these days

By Snowden B. Redfield

An attempt to show, by
applying the theory of in-
ertia forces of reciprocating
parts of an engine, that the
distinct increase in air
pressure at the end of intake
stroke, often observed on air-
compressor indicator dia-
grams, is due to inertia of
the moving air column.
Possible application to
practical purpose of materi-
ally increasing volumetric
efficiency of compressor.

of obtaining the finest points of economy,
"every little bit helps" and if, by an in-
expensive arrangement of piping, an in-
crease of a few per cent, in volumetric
efficiency may be obtained, this may be
counted a material gain.

Basis of Calculation
This article is not intended to be a
complete theoretical explanation of this

Fic. 1. Indicator Diagram from Com-
pressor, Showing Effect of Air
Inertia

phenomenon, but an attempt to point out
in a more or less crude fashion that
there is a theoretical reason for account-
ing for its occurrence on the inertia basis.
Probably some mathematical expert can

Fig. 2. Di.\cram of Forces of Inertia of

Reciprocating Parts with Scotch

Yoke

figure it out much more directly and ac-
curately.

As a basis for calculating such an ef-
fect of inertia we may turn to the method
of calculating the inertia forces of the
reciprocating parts of a steam engine.
We may do this on the assumption that
the motion of the air in the intake pipe

is in a series of pulsations corresponding
to the reciprocating motion of the air
piston. Close to the compressor cylinder,
this probably is very nearly true and the
effect must be similar in a gradually de-
creasing degree at greater distances.
Even at the further end of a compressor
intake pipe of considerable length, these
pulsations are distinctly noticeable by
placing the hand in the current of air
rushing into the pipe. Far enough away
from the piston, the pulsation waves are,
no doubt, distinctly modified from the ap-
proximately simple-harmonic motion of
the piston, but the distance would have to
be very great before the elasticity of the
incoming air would be such as to absorb
all pulsations and result in an even flow
of air into the pipe.

Those who have studied the crank-ef-
fort diagram of the steam engine, or
other machine involving a crank and con-
necting rod, are aware that the starting
and stopping forces at the ends of the
strokes are, with an infinite connecting
rod (or a "Scotch yoke"), equal to the
centrifugal force that would be produced
if all the reciprocating parts were revolv-
ing about the shaft at the radius of the
crank circle. If the force at the end of
the back stroke or beginning of the
forward stroke, which tends to pro-
duce tension in the rods, be considered
positive, the stopping force at the other
end of the stroke, tending to produce
compression in the rods, must be con-
sidered negative.

At some time, then, during the stroke
of the piston, the inertia forces must be-
come zero, the parts having been com-
pletely accelerated and traveling along
in equilibrium. With an infinite connect-
ing rod (Scotch yoke), this point of zero
inertia force occurs at mid-stroke, and a
diagram of the forces of inertia of the
parts would be as in Fig. 2. In this case,
the forces at each dead center would be
alike, and the point of zero force would
be, as said, at mid-stroke.

In this reasoning the difference be-
tween inertia and inertia force must be
distinctly appreciated. At mid-stroke the
inertia, or stored energy, would be maxi-
mum, due to the high velocity; but the
force exerted would be zero, because
there would be no acceleration or re-
tardation. Toward the stroke ends, how-
ever, the slowing of the motion would
transform the inertia into an active force
pressing on the crank pin and assisting
the motion, this force becoming a maxi-
mum just at the instant of stopping. At
this instant, of course, the inertia would
be zero. Whatever force assists the
crank pin toward the end of each stroke,
correspondingly tends to retard the crank
pin during the start of the next stroke, so
no net work is done by these forces.

August 15. 1911

POWER

243

Effect of Connecting-rod Angularity

For the real conditions of a finite con-
necting rod, we may refer to some cal-
culations by Professor Jacobus in the
Transactions of the American Society of
Mechanical Engineers, Volume II, pages
492 and 1 134. In these papers will be
found a table of factors worked out, by
which the theoretical, infinite-rod forces
may be multiplied to obtain the actual,
finite-rod forces. A plot of such a cal-
culation will produce a curve like Fig. 3,
where the forces at the two ends of the
stroke are unlike and where the zero
point is somewhere around 80 degrees of
crank angle, measured from the head
center. These changes are due simply
to the effect of the connecting-rod angu-
larity in putting the piston forward of
where it would be at any one time if the
rod were infinite and had no angularity.

For an infinite rod, the force of in-
ertia, in pounds, at any position of crank
angle is expressed as follows:

r — COS. o

qoOQ

where

If ^ Weight of reciprocating parts,

in pounds;
JV = Number of revolutions of crank

per minute;
7? = Crank radius, in feet;
g= Acceleration of gravity, 32.2;
9= Crank angle, measured from
head dead center.
When S = 0, cos. 9 = 1 and F becomes
the same as the centrifugal force, as al-
ready explained, for the dead-center po-
sition.

From Professor Jacobus' figures, for a
machine having a connecting rod of
length equal to five times the crank arm,
the usual design for air compressors, the
force at beginning or end of either stroke,
should be

F =: — (cos. $ + 0.2)

900 g ^

Application to Moving Column of Air
To apply this formula to a moving col-
umn of air in a pipe, W will be the weight
of air in motion, A^ will be the number of
double reciprocations corresponding to
the revolutions of the compressor crank,
but the value of R will not be the crank
radius. This will be understood from the
fact that, due to the intake pipe being
much smaller In area than the air cyl-
inder, the air in this pipe must travel
faster and further at each stroke than
the piston does. Suppose the intake-
pipe area is approximately 12 per cent.,
or li of the piston area. Then, at any
given time, the air must be traveling 8
times as fast as the piston and, in order
to fill the cylinder, the requisite air will
have to travel 8 times as far in the pipe
as the piston does in the cylinder. In
other words, the air pulsations are 8
times as long as the piston stroke, and
consequently in this case the value of
R in the formula for the air must be 8

times the length of the compressor crank
arm.

As might be expected, the formula
shows that the inertia force is propor-
tional to the square of the number of
revolutions. This means that the greater
the number of stops and starts in a given
time, the greater the forces. Conse-
quently a relatively short stroke with a
given piston speed is conducive to .leavy
forces.

An Example

To take a specific example: Suppose
we have a 36-inch stroke air compres-
sor, running at a speed of 100 revolutions
per minute, a practical figure for modem,
high-speed practice, especially for direct-
connected electric drive with motor on
compressor shaft. Let the cylinder be 34
inches in diameter, and let its average net
area be 900 square inches. The intake-
pipe area, being 's of this, let its inside
diameter be 12 inches, with an actual area
of 113 square inches. The ratio of cyl-
inder and pipe areas then will be 8 to 1,
and so the air speed and length of air
pulsation will be 8 times as great as
those of the piston.

Let us say that the intake pipe is 25
feet long, from entrance at outside of

About 80 Degrees Crank
/Angle .Parts m EquiUbrium,
no Inertia Force

Fig. 3. Similar Diagram with Connect-
ing-rod Length Five Times the
Crank Arm

building to cylinder; let the tempera-
ture of the air be 60 degrees Fahrenheit.
At the instant of stoppage, the air in the
inner end of the pipe will be compressed
by the inertia to some pressure above
the atmosphere, while that at the outer
end will be atmospheric and only that
in the middle section will be, say, half
a pound below atmosphere. It then will
be reasonable to assume that the average
pressure of all the air is atmospheric at
the instant of stoppage and greatest force
and pressure. The weight of the air
contained in the pipe then must be 0.0764
pound per cubic foot, and as the volume
of the pipe of 12 inches inside diameter
and 25 feet length is 19.6 cubic feet, the
total weight of air flowing in the pipe at
this instant will be 1.50 pounds.

Taking, first, the force at the head
center, we have, by applying the formula
already given for a five-crank length
connecting rod:

i.Soir» 100' X 1.5 X 8 X 1.2

F —

9«»9

In this expression, the factor 1.5 is, of
course, the crank radius in feet, and the
factor 8 is the ratio of cylinder area to
Intake-pipe area and, consequently, the
ratio of air-pulsation length to piston
stroke; so that the product of these two

factors represents the imaginary length
of crank arm that would produce the air
pulsations occurring in the intake pipe.
The factor 1.2 is the sum of the cosine of
0 degrees (unity), the crank angle at
head dead center, and the factor 0.2,
calculated by Professor Jacobus for the
connecting-rod length chosen.

The solution of the foregoing expres-
sion is:

F = 73.5 pounds

Inertia Forces Due to Reciprocation

This is the total pressure exerted in
stopping the column of air at the end of
the suction stroke at the head dead cen-
ter, but it must be remembered that, if
the air passage is continuously of the
same area. 113 square inches, this pres-
sure will be distributed over this whole
area and so the pressure per square inch

exerted will be — — = 0.650, or over

?,< of a pound..

Cumulative Effect

Just at this point we should consider a
further inertia effect: the "piling up" and
compressing of the air in the cylinder
and the inner portion of the intake pipe.
The result of such an action would be to
allow the remainder of the air in the
pipe to continue flowing and crowding in,
so that the actual length of air pulsa-
tion is greater than we have assumed. The
effect of increasing this pulsation length
is to increase the value of R in the for-
mula, and thus further increase the force
which we are endeavoring to calculate.
The logic is that, the number of pulsa-
tions per minute remaining the same, the
stopping force must be greater if the
distance traveled, and consequently the
linear speed, is greater; also the addi-
tional air entering the pipe adds its in-
ertia to the effect.

As this would tend further to increase
the pressure, let us assume that the final
pressure would be, say, 0.7 pound above
atmosphere, or 15.4 pounds absolute.
Now, the volume of the compressing
cylinder is 18.7 cubic feet and, as an
estimate, we may include the last 6 feet
of intake pipe in this "piling up" effect.
This gives a total volume of 23.4 cubic
feet into which the incoming air is
crowded from an initial pressure of 14.7
tp 15.4 pounds. Then this 23.4 cubic
feet of air will occupy a space of

21 4 X -^^ := 22 3 cuinc jret
15.4

thus leaving

23.4 - 22.3 ^ l.l cuhic feel

of the last pan of the pipe for more air

to crowd into. With a 12-inch intake pipe

this means a length of 1.4 feet, and this

length is to he added to the value of R,

or the Imaginary radius of the pulsation

wave. As the old value of R was 8 X

I'^ rr 12, we now have 13.4 feet for

the more probable value of R.

244

POWER

August 15, 1911

As the value of F is directly propor-
tional to R, the more probable value of F
now will be

0.650 X ^^-^ =- 0.726 pound

giving a final intake air pressure of over
15.4 pounds per square inch absolute,
which agrees with our assumption when
we began to consider this "piling up"
eflect. It is, therefore, reasonable to
assume that there would be, under the
circumstances of this case, an initial air
pressure just at commencement of com-
pression, of 0.726, or nearly H of a
pound above atmosphere. This would in-
crease the volumetric efficiency by quite
5 per cent., a result well worth striving
for.

Forces Unequal at Head and Crank

At the crank end of the stroke, the
force would be somewhat less, as the
value of COS. 6 would be — 1, and — 1 +
0.2 = — 0.8. This would then make the
pressure at the crank end about 0.484,
or a little less than '_• pound per square
inch above atmosphere, increasing the
volumetric efficiency at this end by over
3 per cent. The average efficiency in-
crease for the two ends then would range
about 4 per cent.

This condition of unequal effects at the
two ends is borne out in practice, for an
examination of the indicator diagrams
containing these inertia effects invariably
shows more initial pressure at one end
than at the other.

To be strictly logical, the increased
quantity of air admitted to the outer end

of the pipe by the crowding and com-
pressing of that at the inner end, should
be taken into account. This increase was
shown to be 1.1 cubic feet, bringing the
weight up to 1.58 pounds. This would
further increase the head-end inertia
force to

'"' X 0.726 ^ 0765 pound

per square inch, or overjii of a pound
pressure; and the crank-end force to 0.51,
or over ' .. pound per square inch. This
would tend to show that we are at least
on the conservative side, leaving room
for pipe friction and other losses.

Practical Considerations

From the foregoing, it would appear
that a longer intake pipe would contain
more air in motion, and so would give
jn increased inertia force and higher
volumetric efficiency. Double the length
of pipe would give double the weight of
air; but, as before intimated, the pulsa-
tions probably are modified considerably
at the end of so long a pipe. Another
matter too, is the loss of pressure by
friction through this long pipe, but this
is really negligible if the air speed is
kept down around 4800 feet per minute.
As an example, tables worked out in
Kent, from B. F. Sturtevant Company's
formulas, show that the loss of pressure
through 25 feet of 12-inch pipe, with a
speed of 4800 feet per minute, is about
?'2 ounce.

It may well be asked "why should the
pipe produce this inertia effect any more
than if the air flowed directly from the

atmosphere into the cylinder, thus avoid-
ing even the small friction of flow. The
answer is that the air in the pipe has a
smooth flow and has an opportunity to
attain the velocity calculated; whereas,
if the pipe were absent, the atmos-
pheric air would flow from all sides at
low speed and, furthermore, all energy of
motion would be lost in eddying at en-
trance. The pipe keeps the air flowing
straight, swiftly and without eddying to
any great extent.

Some persons will realize that this
force or pressure required to stop the
incoming air at the end of the stroke
must be balanced by an equal and op-
posite inertia force required to start the
pulsation at the beginning of the stroke.
No better evidence of this can be desired
than the ever present "hooks" B B, Fig.
1, on all air-compressor indicator dia-
grams. Two excuses usually are given
for these: inertia of indicator parts drop-
ping from the pressure of discharge to
that of intake, and the pressure required
to open poppet valves. The first excuse
seems inadequate with a modern, light
indicator and as to valve resistance, the
writer has seen these "hooks" with Cor-
liss inlet valves open wide before the
stroke started.

It will be well to add tiiat an actual
case of this kind; but which, owing to
several elbows and a strainer in the in-
take pipe, it was impossible to figure
upon intelligently, recently has been
brought to the writer's attention, w-here
the initial pressure of the intake line is
about 1 ' _• pounds above atmosphere at
one end and 1 pound at the other.

Pumps and

In the ordinary single-cylinder and
duplex steam pumps the steam is admitted
during the full stroke of the piston be-
cause of the constant resistance of the
water. This means that the terminal
pressure equals the initial pressure; con-
sequently, the steam consumption per
horsepower greatly exceeds that of an
engine in which advantage can be taken
of the expansive properties of the steam.

There are, however, various methods
of still further utilizing the heat energy
of the steam consumed by a steam pump;
one of which is the addition of a second
cylinder of larger diameter into which is
led the exhaust from cylinder No. 1. If
the areas of the two pistons are properly
proportioned, the steam exhausted from
cylinder No. 1 (high pressure) into cyl-
inder No. 2 (low pressure 1 may be made
to do the same amount of work in the
latter that it did in the former. This is
the principle of the compound steam
pump, and the saving thereby effected
ranges from 20 to 30 per cent., depend-
ing upon whether the steam in the low-
pressure cylinder exhausts into the at-

Pumping

By C. F. Swingle

General remarks eoiieeru-
iiig the elassjpeaiioii a)id
operation of pumps, to-
gether with a feiv simple
formulas for calculating
the dimensio7is, capacities,
head, etc.

niosphere or into a condenser. The usual
number of expansions is from two to
four, depending, also, upon whether the
low-pressure cylinder is run condensing
or noncondensing. But the same econ-
omy in the use of steam cannot be ex-
pected of compound direct-acting steam
pumps as that realized from the com-
pound engine, the latter having the ad-
vantage of a heavy flywheel and the
momentum of the moving parts.

The duty of a pump is sometimes fig-
ured as the number of foot-pounds of

Calculations

work done for each 100 pounds of coal
burned per hour; this is found as follows:

Duty = pounds of water raised per hour
X total lift in feet X 100 ^ pounds

of coal burned per hour
In this expression the total lift means
the vertical distance in feet from the
surface of the w-ater into which the suc-
tion pipe enters, to the surface of the
water in the tank or reservoir into which
the water is discharged. In determining
the suction lift the distance from the
surface of the water to the suctioa cham-
ber may be measured, or if there is a
vacuum gage attached to the suction
chamber, each inch of vacuum equals
approximately one-half pound of atmo-
spheric pressure removed. Suppose, for
instance, that the vacuum gage shows
20 inches; then the suction pressure
will be 10 pounds, and as each pound of
pressure represents a head of 2.3 feet,
the suction lift will be:

20 X 2.3 , ^

— — — -=.25 feet

August 15. 1911

POWER

245

Having noted the water pressure as
indicated by the pressure gage (assuming
this to be 100 pounds), the discharge
head equals

100 X 2.3 = 230 feet.
and total lift equals

23 + 230 = 253 feet.
The horsepower required to raise water
to a given hight may be found by the
following rule:

Horsepower =: number of gallons per
minute X hight, in feet, -=- 3957
The number of pounds of steam used
per minute by a simple, direct-acting
pum.p equals

{Diameter of steam cylinder, in inches)'
X stroke, in inches, X density of
the steam X number of strokes
per minute -^ 2200
For duplex pumps use the number of
strokes made by both pistons. The density
of the steam refers to its weight per
cubic foot at the pressure in the steam
chest or cylinder. For a compound pump,
use only the dimensions of the high-
pressure cylinder. The gallons of water
delivered per pound of steam used equals

0.0034 X (diameter of water cylinder, in
inches \'' -^ [{diameter of steam cyl-
inder, in inches I ' x weight of
one cubic foot of steam at the
pressure used -i- 2200]
The density of steam at various pres-
sures may be ascertained by reference
to steam tables.

To find the number of pounds of water
delivered per pound of steam used, sub-
stitute 0.02835 in place of 0.0034 in
the foregoing expression.

The hight. in feet, to which water can
be raised with a given horsepower may
be expressed as follows:
Hight — 3957 X horsepower -^ number
of gallons
The area of the water piston (or of
both water pistons if a duplex pump is
used) required to raise a given volume of
water per minute, is

Area in square inches — gallons X 231
-=- (length of stroke in inches X
strokes per minute)
The length of stroke required to raise
a given volume of water with a given
number of strokes per minute may be
e-- pressed as.

Stroke in inches = gallons X 231 ^
(area of piston \ strokes per minute).

The piston speed, in feet per minute,
equals length of stroke in inches X
strokes per minute -^ 12.

To find the area of the suction pipe
required for any pump, use the follow-
ing equation:
Area of siiction pipe, in square inches, =

area of water cylinder, in square

inches, x piston speed in feet

per minute -^ 200

For the discharge pipe substitute 380

in place of 200.

The function of an air chamber on a
pump is to insure a steady and uniform
discharge, whereas the object of a vac-
uum chamber is to facilitate the chang-
ing of continuous into intermittent flow.

The hight in feet to which a pump
can force water when taking water under
pressure is

(2.3 (i/i'ii of .^tcam piston, in \
square inches, X steam pressure /
area of uaicr piston
-\- pressure in suction pipe
To find the pressure divide the hight by

Hight -

Developments in British Steam Plants

The production of power by means of
steam is still making rapid strides in
Great Britain in spite of the increasing
popularity of power and suction gas and
the introduction of oil engines as prime
movers. One of the reasons for this is
the abundant supply of cheap coal to be
found in Great Britain, which, with the re-
cent improvements in equipment, renders
it possible to utilize the poorer qualities
of coal, such as slack and duff, which
heretofore have had comparatively little
commercial value. Another impetus which
has recently been given to power-plant
operation in Great Britain is due to the
fact that engineers and manufacturers
have, to a very large extent, abandoned
the old and expensive methods of power
transmission by means of belting and
shafting and have utilized the advan-
tages of the centralized power plant com-
bined with the economical transmission of
power to the point of application by
means of electricity.

Undoubtedly one of the greatest fac-
tors affecting economy lies in the effi-
cient utilization of the fuel in the fur-
nace of the boiler. This movement has
received additional impetus in Great
Britain owing to the very stringent laws
and heavy penalties which arc enforced
by most municipalities upon manufac-
turers whose chimneys emit heavy black
smoke, and every effort is now being
made to obtain perfect combustion by
providing the proper supply of oxygen
to the fuel.

An interesting smoke-consuming ap-
paratus perfected by the Clayburn En-

By James A. Sealer

llie sulient jealiircs 0/ a
few devices which have rec-
ently been developed in
British steam-engineering
practice for the purpose of
increasing the efficiency of
the boiler plant. They in-
clude smoke consumers, a
device for increasing the
circulation of water in a
boiler and a system of re-
turning the water of con-
densation to a boiler.

ginccring Company, of Alanchestcr. is
illustrated in Fig. 1 and. although here
fitted to a Lancashire boiler, is applicable
to any type of land or marine boiler. The
apparatus consists of a group of steel
tubes or colls placed in the flue passages,
combustion chamber or uptakes, accord-
ing to the type of boiler. These coils
are employed for heating the air to a
high temperature before reaching the fuel,
which it does through a specially con-
structed distributing chamber located as
shown in the illustration. The air is fur-
ther heated in the distributing chamber,
from which it is discharged in jets. Inter-

mixing thoroughly with the volatile gases
and thus completing the process of com-
bustion. On entering the furnace the air
is at a temperature considerably higher
than the water in the boiler and is, there-
fore, itself a steam raiser. Atmospheric
air is forced or drawn into the pipe .V
through the coils to pipes A. B and C, the
two latter being provided with valves to
regulate the supply to the superheating
chambers D inside the furnace and E at
the bridgewall. Pipe F is connected with
chamber E at the bottom, and at the top
with the air box G underneath the brick
arch. This air box is perforated with
's-inch holes opposite oblong open-
ings in the front of the bridgewall, as Is
shown in the sectional view. Passing
through pipe C and terininating in pipe F
is a 'i-inch pipe supplying steam jet /,
the object of which is to draw air through
the louvers H and / into the chamber E.
The amount of air is controlled by damp-
ers /? and L, thus furnishing an ample
supply of oxygen which is evenly dis-
tributed and mixed with the hot gases.
An alternative arrangement of the coil ,Y
is to carr>' it to the back of the com-
bustion chamber instead of connecting
at A and then through the combustion
chamber to pipe F. Moreover, In some
cases the coils arc dispensed with and
an injector connected at V. On tests this
apparatus has shown a considerable sav-
ing in fuel as contrasted with a set of
steant jets over the fire, and in one par-
ticular test it showed a saving of lO.S
per cent, in fuel over the ordinary
natural-draft arrangement.

246

POWER

August 15, 1911

Another device which is finding favor
is the torpedo smoke preventer and heat
distributer manufactured by the \otV.-
shire Boiler Company. This consists, as
shovfn in Fig. 2, of a hollow torpedo-
shaped structure composed of special
firebrick blocks supported on firebrick
brackets from the bottom of the flue.
This structure is placed a short distance
behind the bridgewall and in the direct
path of the gases. Air is admitted to the
center of the structure by means of a
pipe extending through the ashpit and
bridgewall, and this pipe is fitted with
a regulating grid placed at the front
of the boiler between the two ashpits.
Under the action of the hot gases the
firebrick rapidly becomes incandescent,
and the air, which has been already
heated in the interior of the torpedo, es-
capes through small openings at the top
and unites with the unconsumed volatile
matter in the gases. The economy of fuel
from the use of this appliance is con-
siderable as it converts the convected
heat, which would otherwise pass away
with the furnace gases, into a store of
radiant heat in close proximity to the
top flue plates and thus causes rapid
steam evolution. From comparative tests
which were made on a Lancashire boiler
with and without the torpedo smoke pre-
venter it was found that a saving of
nearly 10 per cent, in the fuel consump-
tion was effected by installing this ap-
pliance.

edges fitting into grooves in the bottom
of each fire bar. The bottoms of these
half tubes rest in stands spaced about
two feet apart in the furnace. There are
three or more openings to the fire in each
bar, and every bar is designed so as to
form a separate air passage to the fire

being heated, to the back of the wall
where it mixes with the unconsumed
products of combustion. The greater
part of the air induced by the steam jets
passes through the upper half of the
passage formed by the half tubes and
the lower portion of the fire bars and

nL_

Section X-Y

■"Li

Fig. 2. Torpedo S.moke Consu.mer

directly over each half tube which there-
fore acts as an air reservoir or duct for
one-third of each bar in the furnace. A
bell-shaped funnel is fitted at the front
bar which is a different shape from the
ordinary bars, as is also the back bar,
the semicircular openings being omitted.
At the front end of the half tubes or
troughs a flap valve is fitted, which shuts
off admission to them. The steam pipe
from the boiler steam space or other con-

passes to the fire through the openings
in each bar.

With this arrangement wing firing can
be accomplished efficiently by a com-
paratively inexperienced fireman and the
fires may be cleaned and every operatio.i
carried out without turning off the steam
jets. Also, cheap small coal, duff and
coke breeze can be burned effectively
and the semi-automatic regulation of the
air supply to the back of the bridgewall
and to the furnace permits a maximum
furnace efficiency to be attained with a
minimum of smoke.

.._x-<.

Fig.

Clayburn Smoke Consumer

Another interesting device of this kind
is that manufactured under the Wilson
and Furneaux patents by the Tyne Forced
Draught Company which is illustrated in
Fig. 3. It consists of a number of fire
bars of special design placed across the
furnace flue. These rest on three or
more half tubes or troughs running
lengthwise with the boiler, the upper

venient source of supply admits steam
to nozzles in the mouth of each funnel.
The amount of steam emitted by these
nozzles is regulated, first, by a stop valve
on the steam pipe, and, second, by a
valve on the steam pipe connected with
the flap valve on each half tube. Each half
tube leads to a hollow in the bridgewall
which is common to all, and on opening
the flap valves at the front of these tubes
a portion of the air induced by the steam
jets is admitted to the hollow part of
the bridgewall and from thence, after

In addition to the problems concerning
the thorough mixture of the gases and
air in the furnace, considerable attention
has recently been directed to the attain-
ment of a thorough circulation of water
in the boiler, it being claimed that this
tends to reduce mechanical strains, es-
pecially in those types of boilers which
have large areas of continuous surface
exposed to local heat action. Also a good
circulation secures more efficient and
regular detachment of the steam from
the water which is being evaporated. To

August 15, 1911

POWER

247

this fact is attributed the great popularity
of the water-tube boiler in British land
practice. Within certain limits, the faster
the water circulates in a boiler the
greater the emission of steam because
the cooler portion of the water is per-
iodically brought over the hottest part of
the boiler. One of the most interesting
developments in this line is the Leeds
circulator, which is illustrated in Fig. 4,
and which has for its object the con-
tinuous circulation of the water in a
Lancashire or similar type of boiler by
means of baffles suitably placed in the
boiler. In the drawing the line A repre-
sents a sectional division plate, the upper
portion of which stands 3 inches above
the ordinary water level of the boiler,
while the lower edge passes half way
down the furnace flues. In conjunction
with this, line B represents horizontal
plates four feet long, one of which is
carried between the flues and another on
each side of the boiler between the fur-
nace flues and the shell. Further to the
rear is another vertical division plate
D, the upper edge of which stands 10
inches or more above the working level
while the lower edge is carried just be-
low the flues. The feed pipe is carried
the whole length of the boiler, but its
only outlet is near partition D at the rear
end of the boiler.

As active ebullition is continuallv tak-

and, assisted by the aspirative action of
the evaporation taking place over the
boilers, moves forward under the flues as
indicated by the arrows and mixes with
the circulating currents.

When the water reaches the furnace
flues it is nearly the temperature of evap-
oration. This rapid circulation tends to
keep the whole of the boiler at approxi-

ators, etc., drains by gravity into the
sump, which is connected by a riser to
the receiver, the latter being placed five
or six feet above the tops of the boilers
so that water of condensation can quickly
gravitate back to them through a con-
necting pipe and nonreturn valve.

The principle upon which this device
works depends upon the fact that as

.^^

Leeds Circulator

niately the same temperature and thereby
eliminates local distortion. It also has a
marked effect upon the deposition of
sediment.

A recent development invented by
George Wilkinson has for its object the
return to the boiler of the heat units
which would otherwise be lost in the
condensed steam. It is well known that
such losses in steam pipes are very heavy
and with the exception of one or two

\L

vck'-C/'O^

Hollow Bridge

/

f

Fig. 3. WiLt.o.N and Furneaux Smoke Consumi.r

ing place in the section of the boiler im-
mediately over the furnace, a large part
of the water Impinges against and dashes
over the plate A, assisted in so doing
by the curved form of the plate. This
plate prevents the water returning again
and as the heat at this part of the boiler
is not of sufRcient intensify to evap-
orate all the water that passes over A
the surplus descends by gravity, but the
plate B compels it to move further to
the rear and thus increases the length
over which circulation takes place. As
all the feed wafer enters beyond D the
water falls to the bottom of the boiler

special methods of returning the water
of condensation to the boilers the ordi-
nary method of clearing the pipes of
water is by means of steam traps which
are more or less wasteful. The Wilkin-
son thermal column* is designed to
eliminate these troubles and to re-
store the water of condensation in a
heated condition to the boiler. It con-
sists of two chambers, the lower one a
sump and the upper one a receiver. The
water of condensation from the steam
range, separators, steam jackets, radl-

•Thl« l« olmllnr to thi> nt^nm loop iincd
<<xlpDiitvp|)r In Ihtd roiinlrjr.

soon as a body of steam is cut off from
the source of supply it cools rapidly and
the pressure drops. When there is no
water of condensation in the sump the
steam has free access up the riser and
into the receiver, ibut when sufficient
water of condensation has drained into
the sump the bottom of the riser is im-
mersed; this, together with the receiver,
is cut off from the source of steam sup-
ply and the steam already contained
quickly drops in pressure; hence the
water rises and flows into the receiver.
As soon as the sump has been drained,
the steam follows up the riser and es-
tablishes equilibrium of pressure on the
water in the receiver. When this occurs
the water is free to gravitate into the
boiler through the check valve. The re-
ceiver is of such capacity that notwith-
standing the period during which it is
discharging to the boiler, the maximum
amount of condensation formed in the
steam range during each cycle is incapa-
ble of filling the receiver. Should the
receiver and riser become full of water
an automatic relief valve on the re-
ceiver allows the access of water to
escape until the riser again becomes
charged with steam, when the apparatus
again resumes its normal work. Such
flooding does not, of course, occur under
ordinary conditions. The apparatus is so
sensitive that the heat radiation through
good nonconducting covering material is
sufficient to insure its effective working.
The condensed steam can be lifted from
the surnp and returned to the boilers with
a maximum drop in temperature of less
than one degree Fahrenheit per foot of
lift. There is no outlet whatever to the
atmosphere and the wafer Is at a tern-
peraluic close to that of the steam. An-
other important feature of the thermal
'column is that if works by differences
in temperature and not by volume so
that its efficiency is independent of the
amount of condensation which may be
taking place in the steam pipes, cylinders
and other parts of the steam system.

POWER

August 15. 1911

Recent Progress in Diesel

Engines

By F. E. Junce

The efforts of Continental manufac-
turers of Diesel engines during the last
few years have been devoted to some
or all of three aims besides the attain-
ment of utmost reliability of operation:
The adaptation of the Diesel engine to
the propulsion of sea-going vessels, the
utilization of their waste heat, and the
use of low-grade fuels, preferably such
as can be procured in the home market.
In order to attain the first aim it be-
came necessary to create a high-speed
type of engine of light weight. This was
accomplished by reducing the piston

Fig. 1 shows a high-speed Diesel en-
gine of 300 horsepower built by Ludwig
Nobel in St. Petersburg. The air is as-
pirated through side openings in the
crank case, cooling the frame and the
crank bearings on its passage to the
cylinders. A vertical air pump is coupl-
ed to one end of the crank shaft and

essentially, as in the older types of
stationary Diesel engines and need not
be here described.

The high-speed Diesel engines are
lighter and less costly than the slow-
speed engines and occupy less space.
A high-speed four-cylinder engine of
250 horsepower is 11 feet 10 inches
long, 39;s inches wide and 6 feet 11
inches high, while the corresponding
proportions of the ordinary four-cylinder
engine of the same horsepower are 13
feet 9'< inches, 78H inches and 10 feet
10 inches. The weight of the new type
is 26.000 pounds against 50,485 pounds
for the old type — both without the fly-
wheel. The cost of a complete station-
ary plant, including cost of building,
foundation and accessories, when equip-

FiG. I. A Modern High-speed Diesel Engine of 300 Horsepcwer

stroke and therefore the hight of the
engine, at the same time increasing the
piston speed and therefore the power of
the engine. The fear of designers that
a high-speed Diesel engine would be in-
ferior in heat economy to the old typ^
was not confirmed in practice, the fuel-
consumption figures obtained with the
latter type being quite as good as those
of the former.

compresses air in two stages to from
50 to 70 atmospheres (750 to 1000
pounds per square inch). The gover-
nor is provided with an adjustment to
vary the speed between 150 and 400
revolutions per minute; by reducing the
quantity of fuel delivered by the pumps
the speed can be still further reduced.
The working cycle, the details of the
steering gear, valves, etc., are the same.

ped with the high-speed Diesel engine is
15 to 20 per cent, cheaper than one with
the old equipment.

In the following are given some of the
results obtained in a series of tests
which were conducted some time ago on
nineteen high-speed Diesel engines of
from 250 to 300 horsepower capacity.
The engines were all built after the
s;'me pattern, sixteen of them to drive

August 15, 1911

POWER

249

electric generators and three for ship
propulsion; the latter were equipped
with reversing gear. The tests lasted
from 8 to 24 hours, the engines running
under full load all the time. The piston
speed varied between 14.7 and 16.4
feet per second. At the normal speed
of 350 revolutions per minute the en-
gines deliver 250 brake horsepower, and

— Grams x0X>35?75'0unces--^^^

P~

Eii^rS'^'C.^-y^ _

'

_..— — — *'^__P^irt'SX— -"' —

" ^-—"Z-^'^'^''': j^—-*""!!-!

C--'

Z-— — ^— -^^ii^2^-*'

-"''l— — ■ — ^ 1

130 °S

KO 150 200 240 300 350 400 450 o^

Revolutions per Minute '^^ "

Fig. 2. Relation between Speed and
Fuel Consumption

when forced they can deliver continu-
ously 300 brake horsepower at the same
speed.

The consumption of fuel oil remained
within the limits of 185.5 and 205 grams
(6.4 to 7.2 ounces) per brake horse-
power-hour, at full load and 350 revolu-
tions per minute, the exact figure de-
pending upon the length of time which
the engine had been in actual service
before being tested. When a test is
made immediately after erection, the fuel
consumption is, of course, somewhat
higher, owing to the higher mechanical
resistances. On the average the fuel
consumption per brake horsepower-hour
at 350 revolutions per minute and over-
load is 205 grams (7.2 ounces), at nor-
mal load 195 grams (6.8 ounces), at
three-quarter load, 215 grams (7.5
ounces), and at half load 235 grams,
(8.2 ounces). The mechanical effi-
ciency at full load averages 78 per cent.
With slow-speed Diesel engines of the
same capacity the consumption of fuel
per brake horsepower-hour at full load
is 195 grams (6.8 ounces), at three-

es ISO 2(X) 2t0 300 350 400

Revolutions per Minute

fic. 3. Relation between Speed and
Temperature of Exhaust Gases

quarter load 215 grams (7.5 ounces) and
at half load 240 grams (8.4 ounces).
It is evident that as far as the fuel con-
sumption is concerned the high-speed
Diesel engines are not inferior to the
old type havifig a piston speed of 9.84
feet per second.

During the tests the engines worked
partly with raw naphtha of a specific

gravity of 0.88 (at 15 degrees Centigrade)
and partly with solar oil of a specific
gravity of 0.883; also with a mixture of
70 per cent, solar oil and 30 per cent,
masut (specific gravity, 0.88), and finally
with masut alone. Thus the high-speed
Diesel engines were found to work on
the low-grade fuels just as well as the
slow-speed engines. As to the possibility
of reversing, which is of prime im-
portance for marine service, it was
found that reversal from full speed in
one direction to the other occupied from
9 to 10 seconds on the average. The
speed of these engines can be reduced
to 75 revolutions per minute.

Of the investigations of a four-
cylinder engine which were made by Dr.
A\. Selliger and communicated to the
Vereindeutscher Ingenieure, I give the
following abstract: Speed, 350 revolu-
tions per minute; diameter of working
cylinder, 330 millimeters; piston stroke,
380 millimeters; diameter of low-pres-
sure pump, 230 millimeters; diameter
of high-pressure pump, 75 millimeters;
stroke of pump, 180 inillimeters. The
analysis of the fuel naphtha showed
86.82 per cent, carbon and 13.17 per
cent, hydrogen; calorific value, 19,575
heat units per pound. The relation be-
tween fuel consumption, pressure and
speed is graphically shown in Fig. 2
and the change of temperature of the ex-
haust gases in its relation to pressure
and speed is shown in Fig. 3.

The mechanical efficiency, by which is
meant the ratio of the effective output
of the engine to the difference between
indicated horsepower and air-pump
horsepower, decreases somewhat with
the load, reaching its maximum of 80
per cent, at 300 revolutions per minute;
at high speeds it is somewhat reduced.
The heat balance of the process comes
out as follows: About 40 per cent, of
the heat contained in the fuel is trans-
formed into indicated work; about 22
per cent, is absorbed by the cooling
water; about 3 per cent, is lost through
radiation; and the remaining 35 per cent,
is carried away in exhaust gases and
steam.

This is a summary of Doctor Seiliger's
results: The fuel consumption per in-
dicated horsepower-hour (135.5 to 154
grams) at constant mean indicated pres-
sure decreases with decreasing speed of
the engine. The fuel consumption per
Indicated horsepower-hour at constant
speed decreases with decreasing mean
indicated pressure (8 to 4.4 kilograms
per square centimeter). The tempera-
ture of the exhaust gases (.^0 to 2(30
degrees Centigrade) at constant mean
indicated pressure decreases with de-
creasing speed. The temperature of the
exhaust gases at constant speed de-
creases with decreasing mean indicated
pressure. The work absorbed in operat-
ing the air pump (6.4 to 20 horsepower)
is directly proportional to the speed and

independent of the mean indicated pres-
sure. The negative work of mechanical
resistances (36.1 to 82.3 horsepower) in-
creases with the speed and with the in-
crease of the mean indicated pressure.
The proportion of cylinder volume filled
with air (0.90 to 0.83) decreases with
increasing speed (75 to 392 revolutions
per minute) and is independent of the
mean indicated pressure. (The upper
and lower limits of the values obtained
in the test are inclosed in brackets).

Doctor Seiliger found that an increase
of the piston speed from 14.5 to 16.4
feet per second gave no increase in the
capacity of the engine. When the num-
ber of revolutions per minute of the en-
gine tested was increased from 300 to
350, the effective output of the engine
increased from 263 to 304 horsepower.
Between 350 and 400 revolutions per
minute, which is an increase in piston
speed of 15 per cent., the effective out-
put rose only 3 per cent. Increasing the
number of revolutions from 401 to 493,

■5 90
1 80
S70
•5 60

Heaf

Enerqv

not

transformed info 1
Mechanicals Work

1 1 1 1

^ 50

0

losses

1 1
n the Engine

I 30

L.

iJ' 20
10

'

Hec

f £
to

V tr

ansformed
■.al Work

—

^ecVani

0 10 20 30 40 50 60 70 80 90 100
Horsepower Rating per Cylinder

Fig. 4. Heat Balance for Different
Sizes of Engine

which means an increase in piston speed
from 15.7 to 19.6 feet per second, or 25
per cent., the effective output increased
only by 30.5 horsepower, or 10 per cent.

Utilization of Waste Heat

Ordinary Diesel engines convert from
32 to 34 per cent, of the total heat con-
tained in the fuel into available mechan-
ical energy. A theoretically perfect ma-
chine could utilize 56 per cent., so that
the economic eflficiency of Diesel en-
gines would then be 61 per cent. Fig.
4 is a diagram plotted by Professor Josse
as a graphic presentation of the heat
balance for different sizes of Diesel en-
gines; Fig. 5. plotted by Professor Weber,
shows the heat balance for various loads
on a Diesel engine of 200 horsepower.
Besides the losses designated as "energy
not converted into mechanical work,"
part of the "losses within the machine"
may be considered as capable of utiliza-
tion, because a considerable portion of

250

POWER

August 15, 1911

Ihc friction work is transformed into heat
and added to tfie cooling water. On tlie
other hand, there are irretrievable losses
of heat through radiation from the ma-
chine to the surrounding atmosphere, so
that a certain portion of the distances
between the curve A B and the line C D,
depending on the momentary load, must
be considered as the percentage of waste
heat which is available for other pur-
poses.

As regards the cooling water it was
found that in Diesel engines with com-
plete utilization at least 500 heat units
per brake horsepower-hour can be re-
claimed, no matter what the size of the
engine or its load. It was more difficult
to ascertain the exact amount of heat
which can be reclaimed from the waste
gases. A waste-heat economizer built
by the firm of Sulzer in Winterthur,
Switzerland, utilized from 10.5 to 17.8
per cent, of the total exhaust heat while
the cooling water absorbed between 28.2
and 30 per cent., so that, on the whole,
from 171,000 to 264,000 heat units were
utilized, the amount varying with the
arrangement, namely, whether the en-
gine and the economizer are arranged
in parallel or in series. Figuring the
money value of these savings, realized
every day in the year, it is found that
the initial cost of the apparatus for
utilizing the waste heat is insignificant
compared to the economies gained. The
economizer was arranged somewhat in
the fashion of sectional book cases, one
section being placed on top or alongside
of the other and the number of sections
depending upon the amount of heat and
space available.

Similar apparatus are used to raise
low-pressure steam by means of waste
gases, though, for the latter purpose,
Diesel engines are not so well adapted.
All the required heat must be furnished
by the exhaust gases. Hence, even if,
instead of new cooling water, the con-
densate is returned at some 90 degrees
Centigrade to be used over again, the
steam-raising capacity of the plant is
comparatively small, though it is suffi-
cient to supply a secondary steam-heat-
ing plant, or to distil water for chemical
purposes or for filling storage batteries.

Tests made by the firm of Sulzer on
a 1.50-horsepower plant showed that at
least 400 heat units per brake horse-
power-hour can be regained from the
exhaust gases. This rate, as well as the
rate of heat recovery from the cooling
water, increases with decreasing load.
Hence, from the exhaust gases and cool-
ing water combined, at least 900 heat
units can be recovered per brake horse-
power-hour at normal loads, and under
especially favorable conditions the total
amount recoverable may be as much as
1500 or more heat units per unit of out-
put. The division of this total amount
between the cooling water and the ex-

haust gases varies somewhat according
to the mode of operation.

As to the heating surface required for
waste-heat accumulators, 2',', square feet
per brake horsepower are found suffi-
cient, even when taking into account the
gradual settling of sediment on the inner
surfaces. This ratio is given with the
provision that the waste gases yield their
heat to water and on the countcrflow
plan. High water and gas velocities and
long contact surfaces are favorable to
heat transfer, the velocity of the gases
being of far more importance than the
velocity of the water.

When the engine and the econo-
mizer are arranged in series in-
stead of in parallel, it is advisable, owing
to the smaller temperature difference
between gases and water, to itlake the
heating surface larger than 2lg square
feet per brake horsepower-hour, in order

D 1

C

i "

ent Energy not \ j

franSTOrmed into \

Mechanical Work

i

i

"=^

=4

^^

~-

^it-

"

■""'

1

1

■4-

ng,

B

"

—

/

^

frdns-

/

1

1

formed into i
Mec^anica/ ^orfi

/

Dot

fed
1

Lines a

!

1

ct Calcufafed values

0

20

40

60

100 120

Percent, of Full Load '■°""

Fig. 5. Heat Balance for Different
Loads on the Same Engine

to be sure that the exhaust gases will
be cooled down from their normal tem-
perature (200 to 500 degrees Centigrade
according to load and size of the engine!
to 100 degrees Centigrade, even after
the walls of the economizer have been
coated with sediment. For heating air,
owing to the lower coefficient of heat
transference, the heating surface must
also be made considerably larger. It
should be added that the waste-heat
economizer imposes no excessive back
pressure on the engine; the back pres-
sure is not greater than that caused by
the ordinary exhaust piping, while the
economizer also acts as a inuffler, making
the exhaust absolutely noiseless.

Utilization of Low-grade Fuels

The control by the Standard Oil Com-
pany of the world's trade in oil products
has forced the German engineer and

chemist to find a substitute for ;he trust
products which will permit them to sat-
isfy the demand for oils in industrial and
other pursuits from native resources, if
the prices of oils should be raised un-
reasonably or if for any reason the sup-
ply of foreign oils should be cut off.
This substitute has been found in the by-
products of the gasification of coal in
gas-house retorts, coke ovens and gas
producers. In 1909 the total annual
capacity in these coal oils was 90,000
tons from German brown coals and 300,-
0(X) tons from hard coals. Altogether,
400,000 tons of oils can be produced
from German native coal resources per
annum, if the necessity should arise.
Of the hard-coal oils, anthracen and creo-
sote oils are used in Diesel engines,
the consumption being about 6.3 ounces
per brake horsepower-hour for oil of 18,-
000 heat units per pound, costing about
SI per 100 kilograms (220 pounds).

Recently, the firm of Korting Brothers
has made successful attempts to use tar
as fuel for Diesel engines. For start-
ing the engine paraffin oil is used, both
fuels being delivered to the engine by
special pumps. The total heat consump-
tion, if both fuels are used, is approxi-
mately the same as when oil alone is
used. From tests recently made it was
found that a normal Diesel engine of
100 horsepower which ordinarily uses
7340 heat units per horsepower-hour
consumes the following quantities of tar
and oil: at full load, 7.46 ounces of tar
and 0.13 of oil; at three-fourths load,
7.04 ounces of tar and 0.48 of oil; at
one-half load, 6.62 ounces of tar and
0.84 of oil. The low heat value of the oil
was 18,000 heat units per pound and that
of the tar 15,300 heat units per pound.
The tar used in the tests came from sev-
eral gas houses. In two cases it was a
byproduct of English coal; in one case,
of Westfalian coal, and in two cases, of
coal from upper and lower Silesia.

Beside the fuel-consumption test a
duration test of 66 hours at two-thirds
load was made. Upon examination of
the cylinder no residuals from the com-
bustion of the tar were found, nor was
there any sediment on the valves or the
nozzles. In point of speed regulation it
was found that the tar gave the same
satisfaction as the oil fuels. In view
of these favorable results the Korting
firm has given orders for two 600-horse-
power horizontal Diesel engines to be
used in the central station in Dessau,
both to run on gas-house tar.

Old Sandy McPherson and young
Aleck McDonald were working together
over at the power plant, when Aleck
says, "Sandy, what is this 'ere stuff
they call vaakum?" Sandy replies:
"It is naught, lad; it is nothing." Aleck
says: "Sure it must be som'ot, Sandy,
it luust he something, for they keep it
in pipes here."

_L.

August 15. 1911

P O ^- F. R

Using a Dynamo Electric Ma-
chine Interchangeably as a
Generator and as a
Motor
Bv C. C. Hoke

Conditions sometimes arise in power
plants which render it desirable to
operate a compound-wound machine
either as a generator or as a motor, ab-
sorbing energy from a line shaft and

by means of the switching apparatus and
connections shown in Fig. 2. The two

Fig. I. Arrangement of Drive for Small Generators and Pumps

delivering electrical energy in the first
case, or vice versa. This situation has
been met with by the writer on two oc-
casions.

In the first instance a plant was norm-
ally supplied with electricity by means
of a 250-kilowatt direct-current gen-
erator. Two 85-kilowatt machines were
installed for relay service, and these
were belted to a line shaft which
was driven by a simple engine and
which drove a belted air compres-
sor and the condenser auxiliaries
for the entire power plant, as shown dia-
grammatically in Fig. 1. A friction-
clutch coupling was inserted in the
line shaft between the pulleys driving
the two small dynamos and by means of
this clutch No. I generator and the com-
pressor and condenser auxiliaries could
be disconnected from the rest of the
equipment, if desired. Under normal
service conditions this was done, the dis-
connected section of the shaft being
driven by the No. I machine operating
U a shunt-wound motor and taking cur-
rent from the busbars connected to the
2.V>.kilowatf machine. The conversion
No. 1 auxiliary machine from com-
nd to shunt-wound was accomplished

separate switchboards were used on ac-
count of the desirability of controlling
the No. I machine when operated as a

1 he reason tor using the field rheostat
when operating as a motor was to bring
the machine up to the normal speed and
also to secure some speed regulation,
<his being desirable under the varying
load demands. At times the purely
mechanical equipment only was driven
by the engine, letting the generators run
idle, but this was not often the case,
being done only when the load happened
to be too high to be carried entirely by
the 250-kilowatt unit. At times the en-
gine drove the mechanical auxiliaries
and one SS-kilowatt machine in multiple
with the 250-kilowatt unit and frequent-
ly the two small generators were run in
multiple at light load, carrying all of the
electrical load, in order to make repairs
or adjustments on the larger unit. In
this case the centrifugal pump was
usually relieved by a steam pu.iip and
its belt was slipped off. in order to per-
mit throwing all the load possible on the
small generators up to the capacity of
the engine. The compressor was like-
wise run intermittently, being connected
to the main shaft through the medium
of a friction-clutch pulley.

The second case was substantially the
same as the one just described except
that a No. 7 Connersville blower entered
into consideration instead of the air com-
pressor, etc.

This idea may no doubt have been
applied by others but it may be new and

Fir,. 2. Diagram op Switchboaro Connhgtions

motor from a point near the condenser
auxiliaries and as a generator from the
main switchboard.

of value In some readers, in which case
the writer will feel amply repaid for
presenting it.

POWER

August 15, 1911

Maintenance of Railway
Motor Bearings

By C. J. FUETTERER

For any electric-railway company op-
erating a lot of equipments of the same
type, it is almost a necessity to keep
bearings in stock, ready for use. Since
the journals on the motor shafts wear
down more or less after a certain length
of time, however, it would be imprac-
tical to bore all the bearings the same
size, and the best plan to follow is to
keep in stock bearing bushings stand-
ardized, say, to three sizes differing
slightly in diameter; the large size to
be used on new equipments, the second
size for equipments in which the journals
have worn enough to justify turning
them down to the diameter necessary to
take the second standard size, and the
next or largest size of bushing to be
used in a similar way for equipments
requiring a further truing up of the
journals.

In boring the sleeves, allowance
should be made, in order to take care
of oil and unavoidable irregularities, of
0.002 inch per inch diameter of bearing
for solid sleeves and 0.003 inch per inch
diameter of bearing for split sleeves.

Maintaining Voltage by
"Forced Draft"
By Hudson R. Biery

The Indianapolis & Louisville Traction
Company, which was a pioneer in adopt-
ing 1200 volts for direct-current railway
operation, has applied an interesting ex-
pedient for maintaining the full rated
voltage of the generators at its Scotts-
burgh, Ind., power plant under very un-
favorable conditions. The generators are
General Electric 600-volt 600-kilowatt
machines, with two armatures mounted
on a common shaft and connected in
series in order to deliver the 1200 volts
on which the cars operate. As the road
has no substations and as the termini
of this division are each 20 miles from
the power plant, it is essential that the
voltage be held as near 1200 as possible.
The machines were designed to run at
120 revolutions per minute, but owing
to a misunderstanding in the construc-
tion of the plant equipment, it was nec-
essary to put the speed down to 115
revolutions per minute. At this speed
the voltage would range from 1180 to
1160, starting at the first figure in the
morning when the load was light and the
field-magnet coils were cool, and grad-
ually dropping to the latter figure as the
field windings began to warm up.

It was decided that about the only in-
expensive way in which to obtain the
desired voltage was to keep the field
windings cooler and, accordingly, a

blower outfit was installed. A small 5-
horsepower motor running at a maximum
speed of 1200 revolutions per minute was
belted to a 6-inch fan which has a capa-

FiG. 2. View of Pipe through
Machine Frame

city of about 2000 cubic feet of air per
minute. An intake pipe 10 inches in
diameter brings air to the fan from out-
side the building. The motor is equipped
with a regulating rheostat which pro-
vides two speeds, the low speed being
used in the morning when the load is
not heavy and the field-magnet coils are
cool, and the maximum speed being
used when the voltage begins to drop,
as the coils warm up. A 10-inch gal-
vanized delivery pipe extends from the
blower under the floor to the generators.

1

i-

fj/l

■■ ■ ■"":;'^

[I

1 !• ^. .!■

\\

^^^^^^B^ ' -t'^r ^

m

Fig. 1. Arrangement of Coil-cooling
Air Pipe

At the point where the pipe emerges
from the floor between the generators,
the size is reduced to about 3 inches
and divided into two branches. Each of
these branches entirely encircles the
armature of one machine, as shown in
Fig. 1, and a row of holes '<$ inch in
diameter and 2 inches apart in the wall

of the pipe next to the machine delivers
jets of air directly on the field-magnet
coils. Fig. 2 is a view from the other
side of one of the generators, showing
the perforated side of the pipe.

With the blower in operation it is now
possible to maintain a voltage ranging
from 1240 to 1260 without increasing
the temperature of the field-magnet coils
beyond the danger point.

Although the idea of using a blowing
outfit to keep down the temperature of a
generator is not new, it is probable that
the machines here diescribed are the
only ones of their type to which such an
installation has been applied. The sys-
tem was installed under the direction
of H. D. Murdock, superintendent of
the road, and is under the supervision of
chief engineer Wesley Hartley.

CORRESPONDENCE

Hydroelectric Expansion in
California

According to the daily papers, the
Pacific Gas and Electric Company plans
to develop an additional 71,000 hydro-
electric horsepower at a cost of about
.SIO,000,000. This will make the com-
pany's total capacity 260,000 horsepower.
The company now serves about 38.000
square miles in central California.

The present project is said to provide
for the erection of a dam in the caiion
of the South Yuba river, and the con-
struction of two power houses, the first
to develop 50,000 horsepower and the
second, which will use the water again,
to have a capacity of 21,000 horsepower.
The overflow of water is to be used for
irrigation purposes and additional acre-
age is being developed in Placer county
for fruit-growing purposes.

Operating Water-driven Alter-
nators in Parallel

I note in the issue of June 27, an in-
quiry from Mr. Dean relative to the op-
eration of small alternating-current
water-driven plants in parallel. The ac-
companying diagram covers the system
which he outlines and the arrangement
as laid out will be found very convenient
and flexible. I have used the simple sin-
gle-line diagram for the system which
can he easily filled out for three-phase
circuits. Upon analysis the reader will
find that rather free use of disconnect-
ing switches has been made; while this
may be a little extravagant for so small
a system, I strongly recommend that
they be installed, because one cannot
estimate their value in cases where it
might mean the crippling of the entire
system for one small mishap to some
particular switch or other equipment. I
also recommend the tie, shown by the
dotted line, between the transmission
line and the outgoing feeder, as it would

August 15, 1911

P O W E R

253

enable the two small units to carry load
even though the larger plant was out of
service.

I advise the use of station busbars
at the largest plant in order to give
flexibility and to have a means of know-
ing what amount of the load is being
carried by the two small plants.

It would seem best, from what infor-
mation was given in Mr. Dean's letter,
that the instruments be rearranged at
the 200-kilowatt station as sketched and
that the switchboard be made up of three
main panels, namely, one general panel,
one incoming line panel and the feeder
panel; an exciter panel will be necessary
also, if the exciter instruments are not
carried on the general panel, and 1
would advise the use of a swinging
bracket to carry the synchroscope, fre-
quency meter and voltmeter. Voltmeter

prime movers of several alternators of
an installation "wide open" and let the
others do the governing, although this
impairs the regulation to a considerable
extent. If the load on Mr. Dean's line
is such that he can always rely upon at
least 90 to 100 kilowatts, barring the
opening of circuit-breakers, it is quite
feasible to use but one governor, located
at the main generating station; but I
would advise the installation of a gov-
ernor also at the 60-kilowatt plant.

In regard to the actually necessao'
instruments that will be required, I
would say that all those indicated on
my diagram will be found very useful,
but it is not essential that wattmeters
be installed nor that a frequency meter
be used; also, the synchronizing can be
done with lamps, but I would not con-
sider that good modern practice.

The operator must be careful to in-
sert the synchronizing plugs in the cor-
rect receptacles; the "running"' plug
must go in the busbar or line receptacle
and the "starting" plug in the receptacle
on the panel of the incoming generator;
if the generator is already supplying
energy to the system, however, and it
is desirable to "phase it in" on the line
or the busbars, the running plug must
be put in the generator receptacle and
the starting plug in the line or busbar
receptacle. After the machine has been
connected to the line, simply open the
turbine gates until the desired load is
on the machine. The field current should
be adjusted to the same value as if the
machine were not in parallel, for the
same individual load.

When it is desirable to shut down any
machine, simply close down the turbine

Synchronizing
Running

[1 Voif meter JL

Plugs. Switch L^ 'u^i^x

Voltmeter
' ' To BOO Hw. Generator Receptacles

Arrangement of Instruments and Circuits for Mr. Dean's Paralleled Stations

receptacles should be mounted, one on the
general panel, one on the incoming-line
panel and one on the feeder panel. The
synchronizing receptacles should be ar-
ranged in the same order at the main
(200-kilowatt) station, but at the small
stations it will be necessary to use only
one plug, although two could be used.
I have not shown any station busbars
at the two smaller stations, as they will
act only as simple generating stations
feeding one line.

There has been hardly enough infor-
mation given to enable one to advise
intelligently as to the use of governors
at the two smaller stations. If the load
on the system is subject to rather sud-
den variations and liab'" to have a mini-
mum load of less than 100 kilowatts at
such times, it will be necessary to have
a governor on the 60-kilowatt unit at
least. It ia quite common to run the

Throwing the machines on the line is
a very simple matter. Build up the volt-
age on the incoming machine to that of
the system, then put in the synchroniz-
ing plug or plugs, as the case may be,
and the synchroscope will indicate
whether the incoming machine is run-
ning fast or slow. Regulate the speed
of the turbine until the synchroscope
pointer moves very slowly, which indi-
cates a very slight difference in speed.
It must be remembered that changing
the speed of the incoming machine will
affect the voltage of the machine and
that it must he adjusted to equal that on
the system before closing the switch. As
the synchroscope hand approaches the
mark, close the generator switch just
an instant before the hand shows syn-
chronism and the machine "should go in-
fo parallel just as smoothly as a direct-
current machine would.

slowly, gradually cutting down the field
current of the machine also, until the
wattmeter (or, if there is none, the am-
meter) shows no load; then open the
switch.

I should be pleased to hear further
particulars of the installation from Mr.
Dean, either through Power or person-
ally.

Edward L. Nute.
Master Mechanic, Connecti-
cut River Power Company.
Vernon. Vt.

F.lectric liehl and power in all of the
larger towns of the Willamette valley,
Oregon, was shut off a few days ago
as the result of a fire which destroyed
the plant of the Kelly Lumber Company,
one of the largest inland sawmill con-
cerns in the Northwest.

254

POWER

August 15. 19M

ri5.

5 +o Ccsi

Air Discharge V^alves Cooled
by Water

Trouble is had frequently with lubri-
cating oil burning on the valves of the
air end of dry-vacuum pumps. The
illustration shows how I have overcome
this trouble on my air pump, by the in-
troduction of cooling water at the dis-
charge side of the valves.

In order to get cold water I put a tee
in the supply pipe of the air cylinder-
cooling jacket, about midway of the
cylinder, and, with a valve and fitting
ran a >:;-inch pipe from the tee up be-
tween the suction and discharge pipes,
over the top of the valve chest, as shown

Air-discharge Valve Cooled by Water

at A and 6. The two unions, C and D,
are for convenience when removing the
valve-chest cover.

The first pump on which this scheme
was tried had given considerable trouble
after running less than a week. The
valves and valve seats would coat with
burned oil and would drag so badly that
a shutdown and cleaning would be abso-
lutely necessary. Large quantities of oil
would sometimes stop the dragging for
a few moments, after which it would be
worse than ever.

Both the valve and valve seat were
badly cut. That the pump might run
more than 24 hours without dragging,
paper liners were used under the valve
plate, thus giving the main valve about
0,n04 inch more clearance.

At the time water was piped to the
discharge valves of this pump it was shut
down because the valves would drag, but
they had not been cleaned. After con-
necting up the water I started the pump
with a full pipe of water flowing onto
the valves. As the burned oil made the
valves fit tightly a vacuum of between 29
and 29;4 inches was had at the start.

After running about two hours, how-
ever, the vacuum again went back to 22
inches, and the pump was stopped and
the valves examfned. The water had
washed out the burned oil from between
the valves and their seats and also from
the score marks before mentioned, which
allowed considerable leakage. This was
remedied in part by removing the paper
liners under the valve plate, thereby re-
ducing the clearance between it and the
valves.

The pump was again started without
water, but with a little oil, which was
shut off after running a short time, and
allowed to burn until it had filled the
score marks and other leaks enough to
bring the vacuum up to 29 -j inches,
when the water was again turned on,
but in a smaller quantity.

After much experimenting the right
amount of water was determined ( in this
case the water valve was little more than
cracked open I to keep the valves from
dragging and still maintain the maximum
vacuum.

The pump has now been running about
three months without a cleaning. It is
pulling a better vacuum and is running
smoother with less steam on 50 per cent,
less oil than it ever did before.

As the right amount of oil and water
is admitted to the valves, it is churned
to a lather, which lubricates them per-
fectly. I believe a very low-priced oil
would give satisfactory results.

It only required a little water in the
right place, just enough to prevent ex-
cessive friction.

W. E. Bertrand.

Philadelphia, Penn.

Steam I^runi to Prevent Wet
Steam

.A cement plant was started up in
February, 1910. and a great deal of
trouble with the boiler-feed water has
been exnerienced ever since.

Rio Grande river water is used, and
as this river onlv runs three or four
months during the year, a reservoir, in
which is stored the year's supply of
water, has been built about one mile
above the plant At certain periods of
the year when the river is running, the
water is fairly pood, carrying about 20
grains of solids to the gallon. During
these periods analysis is made of the
water every day and it is pumped into
the reservoir when the total solids are
20 grains or less. Due to evaporation
during the summer, the water in the
reservoir gets more concentrated and, in
the latter part of the season, runs as
high as 50 grains to the gallon. The fol-
lowing is the analysis of a concentrated
sample :

Grains

per Gallon

JlaCl

2S2.68

N"a„S()4

13.69

Ca.'^O,

49.03

-Ms.-;( 1,

IS. 14

MkCc I3

13.26

FfCn,

0.530
0.610

\olatiIe and

organ

c mattiT-

21.91

399 . 85

While the water carries a great deal
of scale-forming matter, no trouble is
had. As there are four 400-horse-

.Arrance.ment of Stea.m Drl'.m to
Eli.mi.nate Wet Stea.m

pow'cr water-tube boilers in the power
plant it is only necessary to run two of
them at a time, which gives ample op-
portunity to clean out and make any
necessary repairs on the boilers not in
service. The great trouble is with the
boilers priming, which no doubt is caused
by the amount of calcium chloride which
gradually increases as the water gets

August 15, 1911

P O \V E R

255

more concentrated day by day. Water
is carried in the boilers as low as is
safe, but still a; times the boilers prime,
and in a number cf cases this has shut
down the plant. The boilers are equipped
vith superheaters and ser\'e two 750-kilo-
volt-ampere turbines.

Various people vvho make a specialty
cf treating water have taken up the
matter, but none of them seems to be
able to remove the cause of priming.
The dry pipes have been remodeled and
the boilers equipped with skimmers, but
to no avail.

I would like to have the opinion of
some of Power's readers as to whether
my scheme will overcome this trouble.

To the center drum of each boiler
there is attached a 4'j-inch safety valve,
and a 6-inch saturated-steam line which
carries the steam through a U-bend to
the superheater header. My idea is to
mount a 36-inch by 10-foot steam drum
on each boiler, putting flanges on the
drum diametrically opposite the connec-
tions to ihe boiler for the safety valve
and the saturated-steam line, as shown
ir. the illustration. A drum can be put
on each boiler when it is out of service
by simply removing the U-bend and
safety valve and remounting the safety
valve on the flange directly over its
o'd position. The addition of this dnim
would increase the steam space and the
area of the steam opening from the drum
en the boiler into the auxiliary drum
equal to the area of the 4;-4-inch safety-
valve opening.

I think this scheme would overcome
the priming, but as the addition of this
drum would be quite expensive, I would
like to have the opinion of others before
making the change.

L. D. Gilbert.

El Paso, Tex.

Direct Branch Pipe Con-
nection

It is often necessar)- to tap directly in-
to main pipe lines for the connection of
minor branches. Although a standard
threaded tee or fitting is the correct meth-

a substantial joint and the cunature of
the pipe greatly increases the difficulty.
The effect of the curvature upon the
continuity of the thread in contact is
shown in the accompanying illustration.

The accompanying table shows- the
smallest mains that will accommodate
branch pipes and the number of per-
fect threads. In the mains of the larger
sizes more substantial connections could

DIRECT TAPPING FOR BRANCH PIPE

PowfH

Tapped Hole with Two Perfect
Threads

od of connecting branch pipes, direct
tapping into the pipe is permissible with-
in certain limits.

This method of connecting should

never be employed in case of a drain, or

where considerable vibration occurs, or

'here bending is imposed upon the

ranch by the expansion and contraction

f the main. The thinness of the pipe

alls offers but little opportunity for

Diameter of .Smallest Main Pipe

Diameter of
Branch Pipe

2 Perfect
Threads

2i Perfect
Threads

3 Perfect
Threads

i
i

V

1
2i

2i
.3

l\

I

k

3
4i
6
6

2i

4

1*

7*
8
S

4

8

\l

U
10

l"se combinations equal to or better than
lose given above the heavy line.

Tarred Paper Gaskets

When an air or oil joint persists in
leaking, try a gasket made of tarred
paper. I have been using tarred-paper
gaskets on the flanged joints of two Lom-
bard governor pumps for two years and
find them much better than the lead gas-
kets.

I am also using tarred-paper gaskets
on the flanged joints of an air compressor
with excellent results.

Leroy D. White.

Oldtown, Me.

Making Corliss Valve Gear

Noiseless

The accompanying illustration shows
a method of rendering some forms of
Corliss engine valve gears practically
noiseless. I have taken valve gears
which were quite noisy and made them
almost silent in operation by drilling two

be made, due to the more gradual curva-
ture and thicker gage of pipe.

The number of perfect threads given
is the number of threads in continuous
contact in the branch joint, and as they
have a direct bearing upon the tightness
of the joint, the larger the number or
the nearer the standard the threads
are, the better. The number of threads
given is hardly more than one-third of
the standard;. however, the joints repre-
ss nted above the heavy line give very
satisfactory results.

The heavy line distinguishes the joints
in which the strength is equal to or
greater than that of the branch from
those in which the strength of the branch
is greater than the joint. In the joints
represented below the line the strength
of the branch pipe predominates so de-
cidedly over the strength of the joint
that their use is not advisable.

J. W. Taylor.

Massillon, O.

Installini:; Oil Tanks

I am installing two oil tanks for stor-
ing fuel oil to be used in forging fur-
naces, and expect to place them about five
feet from the ground.

Will some reader of Power who. has
had experience give me an idea of a
cheap and efficient arrangement for trans-
ferring the oil from the tank cars in
which it is shipped to the storage tanks
mentioned? The tank from which the
oil is to be taken will be about 3 feet
below the storage tank. It should also
be borne in mind that oil is somewhat
more difficult to handle in freezing than
in warm weather.

W. W. Warner.

Kent. O.

Silencer on Valve Gear

holes in the crab claw, as shown at B,
and inserting pieces of leather in them.

For some gears it might be better to
insert the leather at the point shown
at M.

C. R. McGahey.

Baltimore, Md.

Eniert^cncy Oil Controller
Two years ago there was installed in
a certain electric-light station a large
high-speed, cross-compound Corliss en-
gine, having a generator mounted on the
same shaft with the flywheel, both re-
volving between two main bearings. The
low-pressure steam eccentric is between
the generator and the flywheel, which
are only 10 inches apart, making it im-
possible for the attendants to feel of the
eccentric while running.

One night the eccentric becaine so
heated that the straps had to be re-
babbitted. When repairs had been com-
pleted, attempts were made to invent
some protective scheme that would
sound an alarm and automatically admit
more oil, if the eccentric again was un-
duly heated. Experiments based on the
fusible temperature of various wax com-

256

POWER

August 15, 1911

pounds and metal alloys proved unre-
liable and troublesome, and were finally
relinquished in favor of a plan evolv-
ing the principle of the expansion of
metals by the increase of heat.

I believe the arrangement adopted
may be readily modified to become ap-
plicable to almost all kinds of unreach-
able bearings as, for instance, the out-
board journals of engines having their
flywheels set so close to the engine-room
wall as to block sufficient passage to
feel of them.

Referring to the sketch, A is a strip
of aluminum anchored at the blunt end
and fitted with a sharp steel tip at the
other, which engages in a recess filed
in the lever B. The spring C is stiff

altogether for a portion of the circular
arc to the left.

Therefore, when the aluminum strip
A expands a trifle, due to a slight rise
of temperature in the metal of the ec-
centric, the lever B will engage with the
lever G and the disk F will be turned an
amount depending on the length of con-
tact between these two levers; thus
opening the valve V and causing the oil
to drip slightly faster at the sight feed
D. When the eccentric becomes so
heated that the lever G swings enough
to allow the pawl to engage ih'e pins,
which are the greatest distance apart,
as H and K, then the disk will move at
every stroke and the ball L (now be-
ing on the other side of the disk) will

A tube cleaner was procured and the
work of cleaning the first boiler began.
When it came to replacing the caps
some difficulty was experienced in mak-
ing the joints tight; consequently it was
necessary to reface some of them sev-
eral times, testing them under pressure
each time.

The chief decided that instead of fir-
ing up the boiler each time it would be
quicker and easier to Ml the boiler with
cold water to the normal running level
and then admit steam from the other
boiler through the m?in stop valve and
bring up the pressure in that way, which
was repeated several times, and noth-
ing happened.

Leon Roundy.

Concord Junction, Mass.

Indicator Diagram

Will some steam-engine expert tell
what is the matter with the engine from
which the accompanying diagram was

Showing Details of Oil Controller

enough to overcome the centrifugal force
of the lever B when the eccentric is in
motion. It is apparent from the rela-
tive positions of the two levers that
slight changes in the length of A will
cause quite a movement in the top end
of B.

The system of lubrication is of the
gravity type, the oil descending from
the upper tank to the sight feed D
through the pipe E. The common handle
of the controlling valve is replaced by
the pin disk F and loosely fitted on the
same stem is the pawl-ended lever G
which engages with the small pins
shown. The distance between these pins
gradually increases for the first quarter
of the disk and the pins are missing

descend on the electrical spring contact
plates M and N and cause an alarm to
be sounded.

The attendant will then watch the ec-
centric closely until it either cools down
from the extra supply of oil or shows
indications of smoking.

M. Cassidy.

South Framingham, Mass.

Steam in Cold Bc^ler

Some years ago I was employed in
a plant the equipment of which included
two Bahcock & Wilcox boilers, carrying
100 pounds steam pressure. The tube
caps had not been removed for a num-
ber of years.

taken? Six different indicators were used
with the same result.

H. T. Fryant.

Jackson, Miss.

Leaky Water Tanks

Most engineers have had more or less
trouble with leaky wooden tanks at some
time or other. I refer to tanks that,
either through carelessness or a short-
age in the water supply, have been al-
lowed to dry out some distance down
from the top.

When a tank once gets in this condi-
tion it is usually difficult to reclaim it.
Some use bran, others sawdust, oakum
and tar.

A method that I have used consists
of putting narrow strips of cardboard
into the cracks between the staves.

This is a somewhat tedious procedure,
but the moment the water reaches the
cardboard it swells and stops the leak. It-
will also give way to the wood as soon as
it begins to swell and finally decompose,
leaving the tank tight with the staves in
their former condition.

.All of the hoops should he pulled up
tightly before commencing and when
the tank is tight it should be given as
many coats of boiled linseed oil as it
will absorb and then finished off with a
coat or two of some good paint.

Earl Pagett.

Coffevville. Kan.

Augus. .5 1911

P O V,' E R

257

The Cornell Economizer

I was somewhat amused to read the
editorial in the July 4 number on "The
Cornell Economizer," because an ex
amination of this device appeals to me
as similar to tr\ing to lift yourself by
your boot straps. The only possible gain
that can be accomplished by a device of
this character is draft, and it is very
doubtful if the cost of repairs and re-
placement in this device would warrant
the installation of any such device for
improving the draft. It would take but
a very small increase in the size of the
stack or the installation of a very small
forced-draft fan to accomplish the same
result, with less wear and tear, less first
cost and less operating cost.

In the two installations coming to my
notice where these have been installed
there has been an increase in the coal
burned and the steam generated, but
it has cost approximately .S300 a year
for replacement of the retorts in each
boiler, besides the labor and cost of the
steam required to operate them. A very
slight change in the arrangement of the
boilers, viz., increasing the flue connec-
tions, would have accomplished the same
results at a first cost of not over S60,
and thereafter no operating cost what-
ever, as the stack in both cases had
ample capacity to handle the boilers.
The trouble was due to poor setting and
constricted flue connections between the
boiler and the stack.

Hfnry D. Jackson.

Boston, Mass.

Design of Turbine Exhaust
Outlet

Among the many good points of the
turbine design shown in the figure on
page 987 of Powfr for June 27, which
is one of the illustrations of the excellent
article of Messrs. Junge and Heinrich on
"The Steam Turbine in Germany," one
in particular deserves marked attention,
that is the exhaust end of the machine
which is reproduced here in Fig. I.

Designers are not agreed on the most
desirable arrangement of the turbine and
the condenser. Some wish the one placed
directly over the other, so that the ex-
haust steam and the large proportion of
water if contains may flow directly and
with the least possible resistance into
the condenser; which is sound, and par-
ticularly so in view of the benefits re-
sulting from the maintenance of a high

vacuum. Others would rather sacrifice
'j inch or 1 inch of vacuum in order to
accommodate a given type of condenser.
In many instances the steam is led from
below the turbine up through a large
pipe 30 or more feet high, thence through
a return leg connected to the condenser
proper. With this arrangement, in case
of failure of the air pump, the water
cannot back up and flood the turbine.

While turbines are usually well
guarded against the danger of flooding,
large units depending upon siphon pipes
and small ones upon nonreturn valves,
the records show that quite a number of

Figs. 1 and 2. Two Designs of Turbinb
Exhaust Outlet

machines have been seriously damaged
through the impact of water coming back
through the exhaust end.

Invariably the trouble happens thus:
the machines running with their usual
smoothness are suddenly and violently
shaken up; the single-disk turbine be-
coming unbalanced, contact takes place
at the safety hearings and the motion
stops; in multistage turbines there is
much grunting and grinding, and some-
times, the trouble being apparently over,
the motion continues, but at the expense
of a large increase of steam to keep up
the load.

Upon examination of the inside of the
apparatus, buckets are found missing at
one or several points of the single-disk
turbine, and very often part of the disk
itself is torn off. The explanation of
the damage is that the water rushing

back from the exhaust pipe (not neces-
sarily from the condenser itself) follows
the walls of the turbine casing, usually
made so as to facilitate the outward flow
of the exhaust steam, and comes into con-
tact with the turbine disk whose periph-
eral velocity is about 1200 feet per sec-
ond. The impact due to the velocity of
the water alone would not affect the disk
if the disk were standing still, but with
the disk revolving at a high rate of speed
the buckets cannot be expected to resist
even a relatively small mass of water,
no matter how strong they may be.

With multistage turbines there is some
discrepancy of opinion as to the effect
of a back flow of water. The turbine
man is almost certain that the trouble
was caused by water; the operator points
out that the last wheel, which is directly
in the path of the water, is cither intact
or else damaged, quite evidently, from
the after effects of what took place in
the adjoining stages. In these stages
there seems to have been an explosion,
buckets on the rotary and guide vanes
in the diaphragm being blown on either
side of a particular spot. Hence the
hasty conclusion that the steam path was
improperly designed, to offset which the
turbine man points out that the ma-
chine had operated satisfactorily until
the accident happened.

Close examination of the casing and
moving parts in several wrecks of large
machines has enabled the writer to offer
a theor\' of the occurrence. In the first
place the condensing process, even with
the best types of condenser, is not ab-
solutely continuous, and that for several
reasons: the moisture of the exhaust
steam is not a fixed quantity, it fluctu-
ates even when the load is kept steady,
due to initial conditions in the boiler,
entrained water in steam lines, partial
condensation or reevaporation in the
various passages of the turbine, etc.;
the presence of variable quantities of
air in the exhaust steam; the variable
work of the air pump or of the circulat-
ing pump; the variable temperature of
the water of circulation, etc. In addition
to these unavoidable causes there comes
the variation of the load itself, which
sets the governor to work on the throttle
valve, thereby causing a strong disturb-
ance in the steam flow thrniighout the
unit, and causing the single or double
columns of steam in the exhaust line
to oscillate.

The exhaust line is seldom lagged;
hence the condensation begins as soon
as the steam leaves the last rotor, and

25S

POWER

August 15, 1911

the water agglomerates in the form of a
sheet flowing against the wall of the ex-
haust duct. When this sheet of water is
interfered with, through the oscillations
of the exhaust steam, it is likely to
move to and fro, pendulum like, and all
the time acquiring more bulk, until a
critical period arrives when it is thrown
violently one way or the other. When
thrown toward the turbine it follows the
walls of the pipe, then those of the ex-
haust head, and if the latter are as shown
in Fig. 2, taken from Stodola's work on
steam turbines, the water following the
direction of the arrows impinges against
the buckets of the last rotor. The in-
terbucket spaces are then sealed for a
very short period, during which the ex-
haust flow is interrupted; the pressure
builds up meanwhile in the several pre-
ceding stages, compressor fashion, until
it becomes strong enough, with the help
of the centrifugal action of the rotors
proper, to overcome the inertia of the
water seal. Then there is a sudden re-
lease, like a mild explosion, which pro-
duces intense vibrations throughout the
fixed and moving vanes, and the latter
give way, bending on either side of the
explosion center, as observed.

The exhaust line is usually provided
with traps or drain pipes capable of tak-
ing care of quite an accumulation of
water, but yet unable to cope with sheets
of water in rapid motion. Disturbances
of this kind are likely to take place in
any condensing installation, and as a
remedy, the use of baffles located in
the exhaust line has been advised at
times. However, with the intelligent de-
sign of the casing reproduced in Fig. 1,
the return water would follow the ar-
rows and not come in contact with the
rotor; and it should prove that the best
safeguard is that which protects the tur-
bine at the very danger point, hitherto
so made as to invite danger.

Albert E. Guy.

Trenton. N. ,1.

Lubricator Condensing; C'lvani-
ber

Mr. Wallace in his letter under the
above title in the July 4 number seems
to be a little mixed up on his lubricator-
condensing proposition. He wishes to
know why the hollow chamber is in the
top of the lubricator. What does it do?
What is it for? Is it in the right place?

This chamber is not necessary to the
working of the lubricator, but it is a
part of it and is in the right place at
the top of the lubricator. It is used to
condense steam and is very essential as
a reservoir, as the lubricator is never
filled to the top.

The condenser will condense a greater
volume of steam in a given time in its
present place than it would 2 feet above
the lubricator.

Mr. Wallace leads his readers to be-
lieve that this chamber is to condense
steam continuously. The only advantage

1 can see in placing this chamber as he
proposes would be to have the condenser

2 feet above the lubricator; this would
fill the pipe below it very quickly and
start the lubricator much sooner than
if the chamber was attached direct to
the lubricator. Then the chamber would
have to be filled and afterward the pipe.

Mr. Wallace, like a great many engi-
neers, seems to think that every time he
fills the lubricator it is imperative that
he should blow a great volume of steam
through the drain valve. If such is the
case, I will not censure Mr. Wallace for
wanting to place a part of the lubricator
at the highest point obtainable as it is
quite worrisome to wait for steam to
condense so you can start oil to your
engine or pump cylinders.

If Mr. Wallace will close the water
valve and open the drain, and then screw
out the filler plug, the lubricator will
empty very quickly.

I have seen lubricator condensers
which had not been emptied in six
months, but they should be blown out
four times a year.

If Mr. Wallace will follow my sug-
gestions he will not think it worth while
to make the changes he has mentioned.
J. W. Dickson.

Memphis, Tenn.

Some Hue Gas Analyses

Since the appearance in the June 6
number of Power of the article on "The
Value of Flue Gas Analysis." by Joseph
W. Hays, we have completed our sec-
ond installation of oil-firing apparatus
for the Canadian Pacific Railway on two
of its passenger steamers, and have made
tests of gases that may be of interest
to your readers, especially to those in
the oil-burnmg sections of the country.

All the tests were made under ordinary
working conditions while the ships were
making normal high speed, and as there
are no stack dampers in these vessels,
the results show that highly efficient
combustion can be maintained with
proper equipment if intelligently handled.

In the case of the last installation on
the steamship "Princess Charlotte," it is
necessary to maintain an overload on its
boilers of practically 100 per cent, in
order to make schedule time. The vessel
carries six Scotch boilers with 18 fur-
naces, having a total heating surface of
14.892 square feet, and the engines de-
velop approximately 6000 indicated
horsepower.

Both ships were converted from coal
burning to oil, with a resultant saving in
fuel and labor equivalent to 30 per cent,
of the former coal consumption.

The accompanying tables show the re-
sults of some flue-gas analyses.

T.VBLi: 1. RE.SULTS OF FLL"E<;.\>

.\.\ALYSKri O.N THE STE.^M.SHIP

■PRI.SfESS MAY"

Date CO, O Co
April 6, litll

ll::iOp.m 14.6 00 U 11

ll:l.">p. m 14.8 0.8 0 0

.\pril 7

12:20 a. m 14.2 d.O 0.6

4:20 p. m 14.8 0.2 0.2

1:30 p. in 12 6 3.4 0.0

.->:00 p. m 14.2 1.0 DO

.'):20 p. m 14.6 0.8 0 0

.^pril S, arrived ISkagway 2:30 p. m.; left for south

11:00 p. m.
April 9

l:4aa. m 14.6 1.2 0 0

2:05 a. m 14.6 1.6 Oo

2:18 a. nr 14.8 0 8 O o

2:32 a m 14.4 1 2 P.'i

2:13 a. m 14.8 l.C 0 0

10:30 a. m 14.8 10 00

.■>:.">0p.m 14.4 2.0 0.0

(>:10p. m 14.0 2..S 0.0

6:20 p. m 14.8 1.8 0.0

11:10 p.m 14.2 1.4 0.0

ll:l.'>p.m 13.0 3.0 0 0

.April 10

](>:2."> p. m 14. S 1.2 0 ii

11:00 p.m 13 8 2.4 0 0

April 11

>i:ir, a. m 11.4 2.2 o (i

S:30 am 13 8 2 2 0 0

9:00 a. ra 13 0 3 0 0.0

9:40 a. ra 13 0 0.0 0.0

10:00a.ra 14 8 10 0.0

.Averages 14 3 14 0 004

TABLE 2. RE.SULTS OF FLCE-GAS
A.VALY.SES ON THE f^TEA.MSHIP

PRINCESS CHARLOTTE"

Date CO, O CO
Jime 6, 1911

14.2 l.s 0.0

15 2 1)0 0.0

14.0 2 2 0.0

10.0 O 2 0 0

15.1 10 0.0

Averages 14 7 1 16 0 0

J. F. BUMILLER,

Manager, National Fuel
Oil Appliance Company.
Los Angeles, Cal.

\^alue of COo Recorder

In the July 1 1 issue, in his reply to
my criticism of his article on the value
of the CO-' recorder, Mr. Vassar makes
the following points:

First, that I was in error in believing
that the principal object in his writing
the article was to question the usefulness
of CO_ recorders, and to put in doubt
the honest purpose of those who are de-
veloping and endeavoring to introduce
this apparatus. He calls particular at-
tention to his statement that CO: re-
corders have a proper place in many
boiler rooms; that what he intended to
show was that "for the average boiler
plant without a technical man to inter-
pret results the CO= recorder is a rather
questionable investment." In this I
agree with him fully. In a boiler house
in which the average intelligence of the
operatives and foremen does not rise
above the ability to shovel coal and
watch the steam gage and water glasses,
and where there is no technical super-
vision available, the installation of a
C0= recorder would be an absolute
waste of money. But. ck)es not the same
thing hold true of water meters and
coal-weighing machines? Would it

August 15, 1911

POWER

259

mean any more to the average coal
heaver to take an occasional look at
the registers of the water meter and the
coal weigher than to squint at the record
on the CO-- machine ? Enough technical
knowledge combined with practical train-
ing to interpret the readings is required
in either case or beneficial results can-
not be expected. On this point probably
all concerned will agree.

The second point Mr. Vassar makes is
that I neither advanced any argument
tending to disprove his statement nor
furnished experimental data to shed light
on the problem. Mr. Vassar's statements
are:

First. "Therefore, while high effi-
ciency cannot be expected with low CO2
it does not follow that high CO; is
accompanied by high efficiency." Sec-
ond. "I do not believe that 00= records
are at all dependable as measures of
furnace efficiency."

Mr. Vassar seems to labor under the
misconception that the record of CO:
in the flue gas, to be of any value,
should be a measure of efficiency. COa
is not claimed to be a measure of boiler
efficiency. The per cent. C0= is a prac-
tically correct measure of the excess of
air, hence a measure of the weight of
flue gas, and in combination with the
temperature of the flue gas it is a prac-
tically correct measure of the sensible
heat wasted up the chimney and. since
the waste up the chimney constitutes
from 60 to 90 per cent, of the total heat
loss, including the loss due to uncon-
sumed combustible gases and carbon in
the ash, it follows that the per cent, of
C0= in combination with the tempera-
ture of the escaping flue gases is not a
direct measure of but a true index to
boiler efficiency. The weight of coal
burned and water evaporated are the
most important factors in determining
the heat utilized; w'hile the percentage
of COj in the flue gases and the tem-
perature at which the gases escape are
the most important factors in determin-
ing the heat wasted.

A knowledge of both of these is desir-
able if not absolutely necessary to in-
telligent boiler-room management. Since
CO: is not a direct measure of efficiency
the diagrams as presented by Mr. Vas-
sar prove nothin:; against the COj re-
corder.

In his rejoinder to my criticism of his
former article, Mr. Vassar devotes con-
siderable space to the difficulty of
sampling the gas, and says. "An auto-
matic CO.- recorder would indeed be a
valuable adjunct to the boiler room if a
fair sample could be secured with any
degree of certainty." I admit that it is
difficult if not indeed impossible to get
a true average sample of the gas flowing
at any moment; that the perforated pipe
is impractical, and that the open-ended
tube is by no means an ideal sampling

arrangement. None the less, if the open
end of the sampling tube is placed near
the center of the gas current just before
entering the uptake, continuous sampling
results in a practically correct average
of the total flow of gas.

CO: recorders require regular, intelli-
gent attention. So does every operating
device in the power plant from the
steam turbine and dynamo, with all their
appurtenances, down to the water pump.
Few if any power-house appurtenances
require less intelligent attention than a
CO-- recorder; many of them require a
great deal more, and they get it, but the
CO2 recorder too frequently does not.

The reason is not far to seek: In the
first place, no man's job depends on it.
The man in charge of a pump knows that
he must keep it in running order or
lose his job, and he gives the pump the
proper attention. Make a man's job
depend on the regular operation of the
CO: recorder and you will be surprised
what little trouble it will give.

In the second place, the CO; recorder
is looked upon by the boiler-house boss,
in whose charge it is generally put, as
an interloper, a despicable telltale. It
does not help him keep up steam or
reduce his labor. It exposes his short-
comings to the superintendent and as a
rule he would rather see it out of com-
mission than running, and if left to him
it will not run.

In concluding his rejoinder Mr. Vassar
asks me "to submit results of a series of
commercial boiler tests disproving my
(his I statement that CO- recorders at the
present stage of the game are not trust-
w'orthy as measures of efficiency."
Since CO-- by itself it not claimed to be
and in the nature of things cannot be
a measure of efficiency, his rtquest is
not germane to the subject under dis-
cussion.

Edu'ard a. Uehling.

Passaic. N. j.

Cost of Furnace I'pkeep

In an editorial in the July 4 issue
some questions arc asked concerning the
"Cost of Furnace Upkeep."

Labor for laying linings and arches
costs about S6 per eight-hour day, and
it will take a mason at least 2' 2 days
to lay them. In the linings every fifth
or sixth course should be laid as headers.
The number of firebrick necessary can
best be computed by the engineer in
charge as bricks vary in size in different
localities. Then, too, the quality varies,
but the engineer should insist upon using
a brand that is satisfactory. Some kinds
peel and flake off and others crack so
badly that they cannot be used a second
time. Firebrick costs from S22 to S-V)
per thousand. Fireclay costs SI per 100
pounds. Salt added to Rreclay mortar.

in the proportion of 1 to 10 pounds of
clay, helps it to set better. In laying
the brick I have found it good practice
to make the mortar very thin, dip the
bricks into it and then lay them close.
The mortar will allow for expansion and
contraction. Walls laid with a thick mor-
tar soon get shaky as the draft draws
out the fine particles.

An arch made largely of iron, -ftith the
iron exposed to the fire, is worthless.
The iron burns and wastes away and the
work must be done over again. They
last four months and cost about SIO, plus
S.S for labor and S5 for inaterial, plus the
time lost for the boiler.

A company in Wisconsin makes an
arch lined with firebrick. The iron
is not exposed, and the arch will last
about 21 years at a cost of about
S20 plus the charge of SIO for setting.
The firebrick setting above the arch will
need replacing at the end of one year
at a cost of $18.

Boilers with overhanging fronts are
cheaper to keep in repair, for then the
arches need not be so wide, the space
between the boiler sheet and the arch
can be kept tight and the sheet at a head-
end seam is amply protected from the
fire.

Boilers with flush fronts must have
the sheet at the seam covered. Some
arches sag when they get hot and the
seam becomes exposed to the fire. Then,
too. the front edge of the arch burns off
and lets the brickwark fall down.

Sometimes the arch tilts forward, but
it can be jacketed back in place and
new brick put under it. The mortar
must be thin, or it will fall out and the
arch will tip over.

If clinkers form on the side walls,
care should be used in loosening them. If
not, the brick will break out with the
clinkers and soon the wall is under-
mined.

The back arch should be of th- same
material as the fire-door arches. A
practise of using old grate bars, angle
irons, etc., has crept in, but this means
hot Sunday work for the firemen and ad-
ditional expense to the firm.

I tried using cement with the fireclay.
It cracked everywhere it should not and
stuck so hard to the bricks that they
had to be crushed to loosen it.

Boiler fronts with two doors using
two arches are preferable to two doors
touching and using one long arch. The
long arch gives less service at a greater
proportionate cost. When boilers are
washed the walls and arches should be
inspected. Often a pail of mortar and
a few bricks applied at the critical time
will save ?I0 in a repair bill, beside the
loss of time for the boiler. Side walls
should stand two years, but in many
cases they must be relaid in six months.
Rnv V. Howard.

Tacoma, Wash.

2G0

POWtR

August 15, 191 !

ler^

Distance Rt'iweeti Beariiigs

What is the safe distance apart to put
line shaft bearings from 1 inch diam-
eter of shaft and upward with and with-
out pulleys between the bearings?

H. E. C.

Two formulas for determining the dis-
tance between the bearings of shaftings
given in Kent are

f' 873 d- = L jor hare shafting
and

V'/ 175 </■ = L. for shafting carrying pulleys
in which

L = Distance between bearings in feet.

rf— Diameter of shaft in inches.

iitdiuiivd Pipe F/ nil ire Dime /is ions

Is the table of flanged Fittings in the
June 27 issue now standard?

D. F. D.

The dimensions given in the table re-
ferred to are those recommended by the
joint committees for the National As-
sociation of Manufacturers, Master
Steam and Hot Water Fitters' Associa-
tion and the American Society of Me-
chanical Engineers. Most of the large
manufacturers are members of one or
the other of these societies, and the
dimensions given are quite sure to be-
come standard.

Latent Heat in Steuni
How many B.t.u. are there in the
latent heat of steam?

A. J. S.
The latent heat of steam is found by
subtracting the heat in the water from
the heat in the steam. For instance:
At atmospheric pressure the total heat
in one pound of steam is 1150.4 B.t.u.
above 32 degrees, and in a pound of
water at the same temperature there
are 180 heat units,

1150.4 — 180 =970.4,
the number of latent heat units in a
pound of steam at atmospheric pres-
sure.

Coni/enser Coolinv System
How many square feet of cooling sur-
face are required in a surface con-
denser to condense one pound of steam
per hour?

J. A. D.
With cooling water at 60 degrees,
1/13 of a square foot of cooling surface
will condense one pound of steam per
hour in ordinary condenser practice.

From 1 '/■ to 3 square feet of cooling
surface are allowed per horsepower, ac-
cording to conditions.

Economy of Intermittent Speed

Is there anything saved by running
a 14x36-inch Corliss engine four min-
utes at 125 revolutions per minute and
then five minutes at 20 revolutions per
minute, working that way automatically?
I. N. S.

So far as the engine itself is con-
cerned, it will develop a given amount
of power with less steam if it is run
under constant conditions at its point
of maximum efficiency than if run in
the intermittent way described. There
may be an advantage in running it that
way, however, when the conditions and
demands of the service to which it is
devoted are taken into account.

Measurements for Snap Rings

How would you get the measure for
and have made a set of snap rings for
a solid piston?

S. P. R.

Snap rings are usually made of a
thickness equal to 1/30 of the diam-
eter of the cylinder plus |^ inch.
The width must, of course, be an easy
fit in the groove. They are generally
turned to a diameter about ;:J inch
larger than that of the cylinder before
being cut for cylinders up to 20 inches
in diameter, enough being cut out to
allow them to spring into the cylinder.
For larger diameters the rings are turned
proportionately larger.

Hol/o-iv Staybolts

Why, when hollow screwed staybolts,
having the hole not less than 'j inch
in diameter and ends riveted over, are
used, may the maximum allowable pitch
be increased by the mean diameter of
the staybolt?

H. S. B.

The supporting power of hollow stay-
bolts, having a comparatively large bore,
is found to be considerably greater than
when the same amount of metal is
concentrated in a solid bolt of smaller
diameter. The threads are coarser, and
have a greater hold, and there is a

greater proportion of the sheet included
in the span directly between the bolts.

Con? press ion in Compound
E/igines

Is it easier to regulate the compres-
sion in a tandem than a cross-compound
engine, and if so, why?

P. J. M.

In a tandem-compound engine the
compression necessary to take up the
momentum of the crosshead, piston and
connecting rods can be divided between
the two cylinders, and a comparatively
small amount of compression on the
large piston has a correspondingly
greater effect.

CyTuider Arrangeme/it in Com-
pound Engines

Which is the better arrangement in
a tandem-compound engine, to have the
low-pressure cylinder nearest the crank,
or vice versa?

C. A. E.

The arrangement is largely a matter
of construction. The large cylinder is
better adapted for direct bolting to the
frame, and the small cylinder, espe-
cially if it overhangs, is better at the
end. The low-pressure cylinder is
cooler, and less heat will go from it by
conduction to the frame and guides.

Position of Water Glass Jf'asher
A claims that the proper place for
the little brass washer in the water-
glass connection in the water column
is in the bottom of the stuffingbox. B
claims that the proper place is on top
of the gasket in the nut. Who is right,
A or B?

M. J. M.
The office of the washer is to prevent
the packing from being twisted or turned
by the friction of the nut while being
tightened, and should be placed between
the packing and the nut.

Change of lt\iter Level

Why does the water rise in a boiler
after the engine is shut down?

W. B. L.

If there is any change in the ap-
parent water level in the boiler when the
engine is stopped it is because the pipe
arrangement is such that there is less
pressure upon the water under the
steam outlet while the engine is run-
ning, causing the water to rise in that
region when steam is being drawn off.

August 15. 1911

P O \V E R

Issuf.i Weekly by tli(

Hill Publishing Company

505 Pearl Street. New York.

ISSSoalb Uicfaiiran Boa1«-van). Chicago.

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cmcuLATioy stateiiext

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newt companies, no back numbcis. Figures
lire lirr, n<t rirriilatioll.

Contents

Remodeled Substation at Reading

Tests of Larse Boilers

Draft and Klffercntl.il Gages

Cost of Power in an Office IJuildinB Plant

Inertia of Air Compressor Intake

Pumps and Pumpine Calculations

Developments In British Steam Plants...

Recent Procress In Diesel Engines

fsInK a Dynamo Electric Machine In-
tcrchnngeably as a Generator and as
a Motor

Maintenance of Railway Motor BearlnKS

Mnlntalninc Vollace by "Forced Draft"..

Ilydro»lertric Expansion In California...

Operating Water-driven Allornalors In
Parallel

252

Practical Letters:

Air Dlscharce Valves Cooled by
Water. .. .Steam Drum to Prevent
Wet Steam. ... Direct Branch Pipe
fv.nnectlon. . . . InHlalllne oil Tanks
...Tarred Paper Gaskets. ... Mak-
ing <-orlUs Valve <:ear Noiseless

Emergency OH Controller. ., .Steam
In Cold Boiler. ... Indicator Diagram
I/eaky Water Tanks 2.".4-2.jH

Discussion I,etters :

The Cornell Economizer. ... I'eslgn
of Turbine Exhaust Oiilloi Lub-
ricator Condensing Chamlier ....
Some riiie Gas Analyses. ... Value
of CO, Recorder .... Cost of Kiirnnce
I'pkeep 2."i7-2."!'

Editorials 2«l-2fi2

Prr>po«ed Basis for Raflng ffniiso-heattng

Rollers and Furnaces 20:^

lle.iilng System Improvements 2<ir.

Engine Wrecked nt Morgnntown. W. Va. 2*17
Educntlonnt Program of Modem Science

Club 2r,7

Power Transmission on Oil
Pou er Vessels

The fact that a double compromise
in speed must be effected in applying the
steam turbine to ship propulsion is an
old stor>- — the now familiar Melville-
Macalpine gear owes its development to
that condition of affairs, and several
systems of electrical transmission have
been devised with the object of reliev-
ing both the turbine and the propeller
of the opposite speed handicaps to
which they are ordinarily subjected.

With the advance in the application
of internal combustion engines to marine
service this question of power trans-
mission from the engine to the propeller
takes on increased importance, not so
much because of speed requirements as
on account of the lack of inherent flexi-
bility which is characteristic of all types
of internal combustion engine. A
marine engine must, of course, be able
to start instantly in either direction and
go to full speed in a few seconds; in
order to obtain this facility of operation
the internal combustion engine requires
substantial aid from some such auxil-
iary as compressed air or a clutch and
reversing gear, the latter being imprac-
tical for equipments of several hun-
dred horsepower.

The use of compressed air for start-
ing gas engines naturally suggests its
use as a medium of power transmission
between the engine and the propeller, but
even the most superficial consideration
of that plan is sufficient to condemn it.
Electrical transmission appears to be the
only practical means of obtaining a flexi-
ble connection between the two extremes
of the power plant, and its advantages
are very great. Aside from the obvious
features of independence of speeds at
the engine and the propeller and the
ability to start the propeller promptly in
either direction and give it maximum
acceleration, there is the enormous ad-
vantage that the propeller can be con-
trolled entirely from the pilot house or
bridge by means of a small lever such
as is used to operate "telegraph" sig-
nals on large ships; no signals to the
engineer are required and therefore
there is no opportunity for misund;r-
standing or delayed response.

Of course, there arc the extra weight
and cost of the motive power equipment,
which constitute serious disadvantages.

They do not seem to be prohibitive in
the case of large interurban railway cars,
however, where almost exactly the same
kind of problem exists. The use of
gasolene-electric cars is increasing
rapidly; why not crude-oil-electric
boats?

A Chance for a Career

Under the above alluring title The
New York Times expatiates editorially,
with that degree of smug cocksureness
so characteristic of the uninformed or
inadequately informed, upon the alleged
magnificent opportunities that hydroelec-
tric development in this country- is creat-
ing for technical graduates. The Feather
River development of the Great West-
ern Power Company is cited as an ex-
ample and the Times asserts that "in the
history of the country's industries there
has never been so pronounced a demand
for the services of technical experts."
It fails, however, to shed any light on
the important subject of remuneration;
the editor contents himself with a glit-
tering generality to the effect that
"young men will hardly hesitate" in
choosing between classical and technical
education "if they wish to shape their
careers toward moneymaking." The
italics are ours.

Of course, by applying suitable defini-
tions almost any statement can be made
to withstand attack. If the editor of
The New York Times considers receiv-
ing a salary of any amount between
.SI200 and S4000 a year as "moneymak-
ing," his assertion is justifiable though
his definition is — well, peculiar. We are
familiar with the general facts relating
to the "careers" of a good many tech-
nical and scientific men but we cannot
think of a dozen who could, even by the
most indulgent interpretation of the term,
be considered "moneymakers." Prac-
tically all of the persons who have made
money conspicuously from engineering
undertakings have done so by com-
mercial ability, nni by the application of
technical education.

However, technical education is price-
less to the man who wants to earn his
living by engineering, and there arc
even better uses of one's brains than
moneymaking: the men who follow en-
gineering because they love it usually
get a good deal more nut of life than do
those who make use of it and them (the

262

POWER

August 15, 191 1

engineers) to amass wealth. But that
does not prevent us from feeling grimly
amused at the idea of advising young
men to take a technical education in
order to become moneymakers.

The Old, Old Ouestion

There was once a bicycle rider who
tightened up the bearings of the wheels
of his machine in order to retard his
progress, but he was about to go down
a steep incline. One could scarcely
imagine anyone doing such a thing if he
desired to make upward progress. Never-
theless, there are approximately a dozen
proposed new license laws and proposed
changes to existing license laws before
the lawmakers in several States and
cities in which engineers are asking the
authorities to maintain a tax of S2 or
more for each license issued and an-
other tax for their renewal. These license
laws are favored by some engineers be-
cause their aim is to protect life and
property and raise the wages of the en-
gineer. It is extremely doubtfi'l if an-
other body of men can be found in the
whole country who ask to be taxed in
order that the public may be protected
from their ignorance and carelessness.

If these laws provide for the proper
inspection and maintenance of boilers,
ever>' engineer and fireman is justified
in working for the enactment of them;
but ihere is no sane reason why the men
should be taxed for the enforcement of
the laws. The public should be safe-
guarded against danger from unsafe
boilers, but it should pay for the pro-
tection, just as it pays for protection
against fire risks, burglars and murder-
ers.

Aside from the unjust imposition upon
the licensed men of the cost of licensing
them, the requirements for obtaining
licenses need intelligent revision. Nine-
tenths of the questions asked by an
examiner have no direct relation to the
safety of a boiler. How can questions
dealing with condensers, valve-setting,
heating, electric and hydraulic elevators,
etc., affect the condition of a boiler or
influence the manner in which it is to
be managed by the applicant? The only
value they have is in indicating that the
man who can answer them correctly is
intelligent enough to handle boilers in a
safe manner. The possession of a license
should be practically a proof of the
ability of the holder to operate boilers
and engines intelligently from the view-
point of safety first, economy second-
arily. The ability to generate a kilo-
watt-hour of energy at a low cost at the
switchboard is no guarantee of ability
to keep the boiler room in a safe condi-
tion. A good many power plants which
their engineers strive to operate eco-
nomically are operating with unsafe boil-
ers.

Another bad feature of the license-law
situation as it now exists is that after
a man has obtained a license he can
operate the plant of which he has charge
with practically no interference or super-
vision on the part of the examiners. Once
a year a State or city boiler inspector
may come around and examine the boil-
ers, if they are not insured, but he is
ignorant as to how the plant is operated
between visits.

Engineers should work for the passage
of laws that will really protect the
public and raise the standard of steam-
plant operation but the expense of ex-
ecuting these laws should be borne by
those who are benefited.

Master Mechanic or Chief
Engineer

A master mechanic recently stated that
it should be the duty of every competent
man holding such a position to be fam-
iliar with the operation and construc-
tion of his power plant, so that, if so
inclined, he can improve its efficiency.

This utterance shows that at least one
master mechanic believes that if the
efficiency of his steam plant is to be
bettered it will be through his own efforts
rather than those of the man in charge
of the steam apparatus. It is reasonable
to suppose that there are many other
master mechanics who hold this view.
One man who has a number of steam
engines in his plant recently stated that
although the men engaged in operating
them were intelligent in a way they
could not make detailed reports of
power-plant operation and happenings
in a clear, intelligent manner. These men
would not be considered competent to
maintain an efficient plant or to make
alterations or additions to it.

If one can judge from the appearance
of things, there are a number of engi-
neers who are incapable of taking com-
plete responsibility for the steam plants
which they are operating. In any such
case the master mechanic of the estab-
lishment, if he is interested in the eco-
nomical operation of the plant, as he
should be, will naturally assume the
position of chief engineer himself and
the steam man will be restricted to a
subordinate rank. When a change like
this occurs, the operating engineer, being
incapable of handling the steam branch
of the business, should not resent the
"intrusion." On the other hand, if the
steam engineer is thoroughly competent,
the master mechanic will find that there
are objections to his interfering with
the management of the steam plant.

There are many master mechanics
who are also the chief engineers of their
plants, and it is probable that most of
them would be only too glad to put the
steam plant in the hands of trustworthy
men and relieve themselves of all re-

sponsibility, if they could find such men.
A competent chief engineer must of ne-
cessfty have the executive ability to
handle the men under him and also
the mechanical training necessary to en-
able him to manage the mechanical
equipment. This does not confine his
ability to seeing that the engines and
boilers are put in service at certain
times, but includes the supervision of
every detail that can in any way influ-
ence the cost of developing power. It
is more important for him to know when
to make a repair than it is to know how
to do so after an accident has happened.
It is necessary also to look ahead and
plan for future improvements and addi-
tions which make for economy.

When an engineer can manage a
steam plant in a practical and efficient
manner he need have no fear of inter-
ference from the master mechanic.

The Human Element

In estimating the cost of power pro-
duction one important factor is too often
neglected. Interest, depreciation, taxes
and coal per kilowatt-hour are calcu-
lated to the third or fourth decimal
place and the prevailing market rates
for attendance are always considered
but the human element is usually either
ignored or forgotten. Consequently, the
actual performance of the plant seldom
equals the estimated results.

Realizing this, many managers have
tried the experiment of interesting the
men in the economical operation of the
plant. This is brought about by some
system which makes the employee's in-
come increase with the employer's gain.
Under such conditions the employees
feel that they are a part of the in-
stitution and have an interest in the work
with which they are identified.

Given fair treatment and recognition
for service actually performed, most men
will soon drop those personal character-
istics which make for friction, because
it will pay to do so.

In the earlier days of steam engi-
neering the piston was made more or less
steam tight in the cylinder by means
of a packing of braided hemp which
was renewed as the discretion or caprice
of the operator dictated. The idea that
the piston packing should be a part of
the machine furnished by the builder
was never entertained until an itinerant
machinist designed a form of metal-
lic packing which he made on the prem-
ises whenever he effected a sale. If
it is a builder's duty, as it seems to
be, to furnish pistons and valves which
will not permit the leakage of steam,
why is it not equally his duty to pro-
vide for waste around valve stems and
piston rods by furnishing a steam-tight,
easy-running metallic packing which
shall be comparatively durable?

August 15, 1911

P O ^' E R

263

Heating and Ventiia

Proposed Basis for Rating

House-Heating Boilers

and Furnaces*

By Frank L. Blsey

A study of several hundred tests made
by the University of Illinois engineer-
ing-experiment station on various types
and sizes of small boilers and furnaces.
and also of tests made on other and
larger units, the results of which could
be relied upon, are the data upon which
the results given in this paper were
based.

The practice of using 10 or 12 square
feet of heating surface in a boiler as
equivalent to 1 horsepower is hardly
warranted in house-heating boiler work.
since the rate of combustion, ratio of
heating surface to grate area and conse-
quent variation in efficiency may in-
validate such a system. As a matter
of fact, the amount of surface required
may vary anywhere from 5 to 50 square
feet per horsepower.

Various forms and combinations were
tried and discarded, and it was finally
decided to use the term horsepower as
the unit of heating effect, as applicable
to both steam boilers and warm-air heat-
ters. Taking the American Society of
Mechanical Engineers' standard of 34.5
pounds ot water evaporated per hour
from and at 212 degrees Fahrenheit as
equivalent to I boiler horsepower, gives

34.5 X 970.4 = 33,479 B.i.u.
as also equal to I horsepower. In the

H....j.H+>t-^^^^-!-:-t:

Fic. I. RELATroN OF Horsepower Con-
stant TO Rate of Combustion

case of the boilers, the equivalent evap-
oration from and at 212 degrees Fahren-
heit per hour divided by 34.5 gives the
horsepower developed. With the warm-
air furnaces the pounds of air heated

•Atwtmrt of n nnpor rcnrt twfor** Hip Amnr-
Imn »o<-l<>»T of lirnilne «n<1 VpntliminE Kn-
gltiPcrs. rhlrneo. .IiilT ft to S.

per hour multiplied by the rise in tem-
perature and the specific heat of air,
gives the number of B.t.u. delivered per
hour to the air. This in turn divided by
33,479 gives the horsepower developed
by the furnaces.

Having determined the total horse-
power developed by the various units
tested, the next step was to find some
dimension, relation or ratio to which the
horsepower developed could be referred,
and so obtain a unit to which the horse-
power would bear some definite relation.
It was found that the horsepower de-
veloped upon each square foot of grate
by 1 pound of dry fuel burned per hour
on each square foot of grate surface
was remarkably constant. This is true
for any one boiler or furnace when
burning dry coal per square foot of grate
per hour between the limits of 4 to 8
pounds for small units and 5 to 10
pounds for the larger units, when using
coals of a similar quality. This is shown
clearly in Figs. 1 and 2 for two separate
units, each using two classes of fuel.
This value, termed a horsepower con-
stant and designated by K. was obtained
for each test analyzed by dividing the
horsepower developed by the grate area,
and this quantity in turn by the rate of
combustion. Since frequent reference
will be made to the grate area and the
rate of combustion for any one heating
unit, these terms will be designated by
G and F, respectively.

While K was constant for any one unit
and for a similar quality of coal, yet
different units gave different values of
K. It was found that the higher values
of K were obtained from units having a
greater number of square feet of heating
surface for each square font of grate,
this number being the ratio of the total
square feet of heating surface to the
square feet of grate. This ratio will be
designated by R. For a similar quality
of coal, the values of K from the dif-
ferent units were then plotted to the
corresponding values of R, as shown in
Fig. 3. It is seen that ihei* exists a

verj- definite relation between the values
of k and R.

This relation appears reasonable, for,
other conditions being equal, higher effi-
ciencies will be obtained with higher
values of R. Thus in practice it is cus-
tomao' to use additional sections, re-
sulting in higher values of R, and also
greater capacity. The relation between
K and R was found to be independent of
the size of the unit tested, inasmuch as
increase in size is usually accompanied
by an increasing value of R. This ac-
counts for the higher efficiencies obtained
from large units.

It is well known that the use of vari-
ous grades of coal results in different
efficiencies in the same unit. From a
study of the tests made it was found
that the coals used could be divided into
three general classes, designated as
classes A, B and C. Class A includes
anthracite, coke and semi-bituminous
coals. Class B includes good grades of
bituminous coal, such as is mined in
Williamson, Franklin and Saline counties
of the southern district of Illinois. Class
C includes the poorer grades of bitumi-
nous coals. It has already been pointed
out that when using any one class of
coal a definite relation exists between K
and R. Although different values of K
are obtained when using the different
classes of coal, yet each class has its
own definite relation between K and R.
This is well illustrated in Fig. 3, where
the three curves refer to the different
classes of fuel.

Table 4 shows the average proximate

L^

Fic. 2. Relatihn of Horsi phwer Con-
stant TO Rate of Combustion

analyses of the three classes of coals
during these tests. The term "good" or
"poor." as here used, refers to the per-
formance of the coal when used in small
house-heating units and not for large
power boilers. The comparatively low
furnace temperatures attained in the
smaller f'lrnaces make it impossible to

264

POWER

August 15, 1911

burn completely the excessive amounts
of volatile matter in these coals desig-
nated as "poor bituminous." For this
reason they soot up the flues and cut
down the efficiency.

It is customary, to get the same heat-
ing effect, to build warm-air furnaces
with a much greater value of R than is
used with steam and hot-water boilers.
This is because more heat can be trans-
mitted through 1 square foot of heating
surface to water than to air. Tests show
that in warm-air furnaces R must be
from two to three times as large as in
boilers to give the same efficiency, and
corresponds very closely with practice.

As a result, K does not bear the same
relation to R in furnaces as in boilers,
due to the greater value of R necessary
in furnaces to obtain the same value of
K. It follows that the relation of K to
R varies not only with the different class
of fuels used but with the different type
of heating unit (see Fig. 3).

Fig. 3 shows the relation between the
horsepower constant K and the ratio of
total heating surface to grate area R.
The general relation of the curves A, B
and C for furnaces and curves B and C
for boilers is very similar, the better
fuels giving the higher efficiencies. This
difference increases slightly as the value
of R increases. An increase in the value
of R is accompanied by an increase in
the value of K only in so far as the value
of R is confined to the limits found in
practice. These limiting values of R for
boilers in which this relation was found

point. Nevertheless the indications are
that Ithis is the case. There would
eventually come a point where the tem-
perature of the flue gases would be re-
duced to so nearly the temperature of the
surrounding water or air that no further

ft is evident that an increase in the
radiating surface of boilers is productive
of greater gain in efficiency when using
Class A fuels rather than the ordinary
bituminous coals. With boilers having
a low value of R a good grade of bitumi-

VALUES OF HORSEPOWER CONSTANT K FOR VARIOUS VALUES OF
R.\TIO R, STEAM BOILERS

R

Fuel A

Fuel B

Fi-EL C

Ratio of

Total

B.t.u. pel

Square

B.t.u. per
Hour De-

bquare

B.t.u. per
Hour I)e-

Square

Heating

K

Hour Ue-I

Feet of

A-

Feet of

K

Feet of

Surface

Horse-

livered

Jtadia-

Horse-

livered

Radia-

Horse-

hvcred

Radi^

to Grate

power

to the

tion

power

to the

tion

power

to the

tion

.Vrea

Constant

Water

Sen-ed

Constant

Water

Served

Constant

Water

Served

S to 1

0.166

5,560

22.2

0.177

5.925

23.7

0.159

5,320

21.3

9 to 1

0.181

6,060

24.2

0.182

6.090

24.4

0.163

5.455

21.8

10 to 1

0.196

6,560

26.2

0.187

6.260

25.0

0.167

5,590

22.4

11 to 1

0.211

7,065

28.3

0.192

6.430

25.7

0.171

5,730

22.9

12 to 1

0.226

30.3

0.197

6.595

26.4

0.175

5,865

23.5

13 to 1

0.241

8,065

32.3

0.203

6.785

27.1

0.179

6,000

24.0

14 to 1

0.256

8,570

34.3

0.208

6.960

27.8

0.1S3

6,135

24.5

15 to 1

0.271

9,070

36.3

0.213

7.1.-50

28.5

0.1S8

6,280

25.1

16 to 1

0.286

9,575

38.3

0.218

7,300

29.2

0.192

6.420

25.7

17 to 1

0.301

10,075

40.3

0.223

7.465

29.9

0.196

6,550

26.2

IS to 1

0.316

10,575

42.3

0.229

7,665

30.7

0.200

6.690

26.8

19 to 1

0.331

11,080

44.3

0.234

7,835

31.3

0.204

6.830

27.3

20 to 1

0,346

11,580

46.3

0.239

S.OOO

32.0

0.208

6.965

27.9

gain would be effected by increasing the
radiating surface.

Curve A, in the case of the boilers,
shows a much greater difference in favor
of the high-carbon over the bituminous
coals as the radiating surface is in-
creased. This difference is probably due
to the comparatively restricted flue pass-
ages as ordinarily used in steam and hot-
water boilers. In warm-air heaters the
radiator is usually made of such ample
proportions that less difficulty is e.xperi-

FiG. 4. Horsepower Developed and Load Carried by Various Sizes of Boiler

to hold are between 8 and 15. This
range for furnaces, however, is from 15
to 38. It is quite probable that the
higher value of 15 set for R in the case
of boilers can be increased to 20 or even
above, but it was impossible to obtain
sufficient data to prove absolutely this

enced with soot deposits. If the ratio of
heating surface to grate could be in-
creased, and at the same time the gas
passages kept of ample size, cur\'es B
and C would no doubt tend to assume an
inclination more nearly like that of
cur\'e A.

nous coal may be expected to give as
good results as with anthracite or east-
em semi-bituminous coals.

As the values plotted in Fig. 3 can
be represented by straight lines within
the limits of the tests used, the next step
is to derive a formula and determine the
proper constants applicable to the various
sets of conditions.
Let

G = Area of grate surface in

square feet;
F= Pounds of dry fuel burned
per square foot of grate
surface per hour;
R = Ratio of total heating surface

to grate area;
K = Horsepower constant =
horsepower developed per
square foot of grate, per
pound of dry fuel burned
per square foot of grate
per hour;

Fig. 3. Relation of Horsepower Con-
stant TO Ratio of Heating Surface
TO Grate Area

h.p. := Total horsepower developed;
Ci and Ci — Constants for any one set of
conditions.
It will be noticed that the average de-
viation of the points from the lines as
drawn is less than 3 per cent., and that
the maximum deviation is 7.5 per cent.

August 15, 1911

P O W E R

265

This shows how closely actual perform-
ance, as shown by a study of several
hundred tests, may be approximated by
the use of the formulas and constants
given in Table 1.

Then these lines are represented by
the formula

K = C^ R + C2 ( 1 )

The American Society of Mechanical
Engineers' standard of 34.5 pounds of
water evaporated as 1 horsepower was
used; hence one horsepower = 33,479
B.t.u. This in turn divided by 250 gives
the number of square feet of direct
radiating surface carried — taking the
standard of 250 B.t.u. emitted per square

VALUES OF HORSEPOWER CONST.\NT K FOR V.iRIOrS VALUES OF
RATIO R. WARM AIR HEATERS

Ffei. a

Fuel B

FrEi. C

/?

Equiva-
lent

Equiva-
I'-nt

Equiva-
lent

Ratio of

Cu.Ft.

Cu.Fl.

Cu.Ft.

Total

B.t.u. per
Hour De-

of Air

B.t.u. per
Hour De-

of Air

B.t.u. per
Hour De-

of Air

Heating

K

Heated

K

Heated

A'

Surf act-

Horse-

livered

per Hour

Horse-

livered

per Hour

Horse-

to Gratf

l)0wer

to the

from 0

power

to the

from 0

power

to the

Art-a

Constant

Air

to 70°F.

Constant

Air

to 70° F.

Constant

Air

to 70° F.

IS to 1

0.168

5610

3906

0.151

5040

3511

0.131

4385

3054

16 to I

0.171

5730

3993

0.153

5130

3573

0.133

4455

3103

17 to 1

0.175

5855

4078

0.156

5220

3636

0.135

4520

3148

IS to 1

0.179

5980

4165

0.159

5310

3699

0.137

4585

3194

19 to 1

0.182

6105

4251

0.161

5400

3761

0.139

4655

3243

.20 to 1

0.186

6225

4338

0.164

5490

3824

0.141

4720

3288

21 to 1

0.190

6350

4424

0.167

5580

3887

0.143

4785

3333

22 to 1

0.193

6475

4510

0.169

5670

3950

0.145

4855

3382

23 to 1

0.197

6600

4597

0.172

5760

4012

0.147

4920

3427

24 to 1

0.201

6725

4683

0.175

5850

4075

0 . 149

4990

3476

25 to 1

0.205

6845

4769

0.178

5940

4138

0.151

5055

3521

26 to 1

0.208

6970

4855

0.180

6035

4204

0.1.53

5120

3566

27 to I

0.212

7095

4942

0.183

6125

4266

0.155

5190

3615

28 to 1

0.216

7220

5028

0.186

6215

4329

0.157

5255

3660

29 to 1

0.219

7340

5114

0.188

6305

4392

0 1.59

5325

3709

30 to 1

0.223

7465

5201

0.191

6395

4455

0.161

5390

3754

31 to I

0.227

7590

5287

0.194

6485

4517

0.163

5455

3S00

32 to 1

0.230

7715

5373

0.196

6575

4580

0 165

5525

3849

33 to 1

0.234

7835

5459

0.199

6665

4643

0.167

5590

3894

34 to )

0.238

7960

5545

0.202

6755

4705

0.169

5660

3943

35 to 1

0.242

8085

.5632

0.205

6845

4768

0.171

5725

3988

36 to 1

0.246

8210

5718

0.208

6935

4831

0.173

5795

4034

In this formula C, and C: have definite
values for any one type of heating unit
in various sizes when using one class
of coal.

The various sets of values for C, and
Ci have been carefully determined and
are tabulated in Table I. Thus the for-
mula for warm-air heaters for a fuel in
class A becomes

K = 0.0037 K — 0.112

For any unit under consideration this
formula gives us the value of K, or the

TABLE 1. VALUE.S OF C, AND r, FOR THE
FORMULA K^CJt + r,

foot per hour. With warm-air furnaces
the B.t.u. delivered to the air per hour
divided by 1.4356 (the heat required to
raise one cubic foot of air from zero to

plied by G and F gives the total horse-
power developed, total B.t.u. delivered,
or total heating effect, under the condi-
tions assumed. Fig. 4 for boilers and
Fig. 5 for furnaces have been drawn to
show more clearly the effect of the vari-
ous combinations of the factors already
discussed. From these figures can be
readily traced the entire course from
heat unit to the horsepower developed
for any set of conditions.

Referring to Fig. 4, assume a boiler
with a value of /? = 12.5, a grate area
of 6 square feet and a rate of combus-
tion of F =; 6 pounds. Then, if anthra-
cite is to be used, follow the vertical
line upward from the point where R —
12.5 until it intersects the line A. From
this intersection follow the horizontal
line to the left through the point K —
0.235 until it intersects the line G = 6.
From this point trace the vertical line
upward until the line F = 6 is reached.
Following the horizontal line to the right
from this point it is seen that under
these conditions the horsepower de-
veloped is 8.5. On tracing it farther to
the right until the diagonal line is inter-
sected, then dropping downward on the
vertical line, the equivalent heating sur-
face served is found to be 1150 square
feet.

In the same manner for warm-air fur-
naces on Fig. 5, the values can be traced
as shown. From R — 25, fuel B, G —
7. F = 6, to 7.8 horsepower or a heating
effect of 180.000 cubic feet of air warmed
per hour from 0 to 70 degrees Fahren-

1 F...,.

C,

c.

[ Class A, anthra-
1 cite. s*?mi-bitnm-
Ri<M>in I inoii,"!. coke
ouiiem. , ^j., ,|j. i,|,„minou.'.
1 CI*!'! (;. poor (fradi-
' 1. biluminou.H .

0.01.50
0.00.52
0.0O41

0.046
0 135
0.120

1 Cla«i A. anthra-
1 cite. 9omi-l)i(um-
Warm-Air ' inoil.H. rokc

"**"", CTa-l.-liiiciminou.'.

r,1a»s c. jKMir era<li-

1 I IjitiiminoiiH

0 0037
0 002
0 0020

0 112
0 110
0.101

horsepower that is developed on each
square foot of grate surface by each
pound of fuel burned per square foot of
grate per hour. Knowing K. the grate
area, and the most desirable rate of com-
bustion, the total horsepower developed
can be readily determined by the for-
mula

h.p. = K y G y F (2)

\-\^v4 I

1 1 1 1 i ! 1 1 1

'

_L-

~"

T

--

-

-

-

-

--

--

-^h

N i X

\ \ \ 1

I M M 1 M i

I

1 !

X

V\ \\-

RATE or COMBUSTION

F^io.oPco.LWBBO. rr

:

w

1

/

^ >

xxw

J

/

N.

•\ xV\\

1 /

^s^

vXO

^

\>

\^ N.

xo

\

>f-!-

1 1

'

/

'

N

\X\,v

1 1

1/

^\^

\i s,

I

y

^^\,

^\

nS^>S^

1

^

^.^^

'-v

sN

\Xv\

>

y

l"**^.^

■^v^x\

i 1

1

20

/

~"~\i^^^

OXX$^

/

1 1

K.' -^

tSxxs^

/

-v.^^

>^c^

<NS$^

v-'"'i

1

/

'

vN\

%

.0

/

<^

1 '

.'i

i , T'"'^

$

^^

'■7

/

1

^

k.

1

■

: 1

/

toni^, CU.FT. or*iq M^*Tt-i PE«-oun focm o'to 7o'f.| |

(

I

aooooo

1

iA/tXM 1 '

immao | | |

ox

'

m

fH^-

ORATc'aOEA

Wn

0..

.»--".

L^

^?$*

W///!'

'

1

i 1 1 1 ; r

I

^

^^

>xx

y//J i\

.'

O.lt

i

'

.>^

V/

///

::::r — *--— _

! !

^

^

1

^^^

/^VVV////i

r-

" - F

rrr:

^■^

^

^■'Z/yV///.

/////'

J_

y"^^^^

^ ^

W:/J

N- '

i^^^y^

AZ//

// /v /ir

T: :i '.'.'

1

i ;... L,

...

y

A

-il

^

vrZ//

-J

/ ./.i

u.

^

L

i

_

'"

io

"

^

jl

"'

°"""v:-

±

L.

1

Fig. 5. HoRsr;po^^'ER Developed and Load Carried by Various Sizes of
Furnaces

70 degrees Fahrenheit) gives the equiva-
lent cubic feet of air healed from 0 to
70 degrees Fahrenheit.

As previously explained, the value of
K, of the B.t.ii.. or of the heating effect,
as given in Tables 2 and 3, when multi-

heit. This operation can be reversed,
with cither Fig. 4 or 5, thus worl<ing
from the amount of heat needed back to
the unit to be selected.

Any basis of rating selected for heat-
ing installations should be equally ap-

266

POWER

August 15. 1911

plicablc to steam and hot-water boilers
and to warm-air furnaces, as they are
used for similar requirements.

A unit of rating should be of such a
character that it may be easily expressed
and comprehended, of some standard
form that may be compared to that used
for power-boiler rating.

The tertn horsepower as used in the
American Society of Mechanical Engi-
neers' rating for power boilers is a meas-
ure of heat delivered, is applicable to
both boilers and furnaces and fulfils
better than any other term the above
requirements.

CORRESPONDENCE

ment was supplemented w-ith a goodly
portion of the blast of air blown through
Heating Sj^Stem Improvements ""'^e'" relatively high pressure at each

ejectment. As a consequence, the heater

The equipment of a certain vacuum-
heating system consists, in part, of an
open feed-water heater. As indicated in
Fig. 1, a drain pipe from the main ex-
haust line had been run to the heater
and connected to the opening, that was
originally designed for a vent, directly
to the atmosphere. This left the heater
without adequate relief for the air lib-
erated from the feed water and therefore
the air continued to accumulate to the

T.\BLE 4. AVER.\GE P1!0XI.\I.\TK .-V.V.A.LV.SLS OF FUEL.S USED, FUEL AS FIKEI)

Fi.xed
Carbon,
Per Cent.

Volatile,
Per Cent.

Moisture,
Per Cent.

Ash,
Per Gent.

Sulphur,
Percent.

B.t.u. per
I.b.

78.2,T
80.50
74 . .57

3.26

18.79

3.49
6.30
1.49

11.15
9.94
5.15

1..30
0.90
0.74

12,820

Coke

.Semi-bituminous

12,01.5
14,780

(;ias.s B — bituminous

49.07

a4.9i

6.S4

9.19

1.S2

12,2.50

Class C — bituminous

4 1 . .59

:is . 0.1

10.79

9.57

2.97

11.340

The heat generated, or the power de-
veloped, on each square foot of grate
by the combustion of I pound of fuel
on that s.quare foot of grate has been
found to be practically a constant, under
the conditions as already outlined. This
is true of both boilers and furnaces.

This constant bears a definite relation
to the size of the heating unit as ex-
pressed by the ratio of its total heating
surface to grate area. Based on the re-
sults of actual tests, this relation can be
expressed by a simple formula and the
above constant determined for different
units and sets of conditions.

The difference between the horsepower
developed by actual test and that cal-
culated by the use of this formula is
comparatively slight. The calculated
horsepower may be used in connection
with the ordinary heating job with entire
satisfaction.

The use of the diagrams. Figs. 4 and
5. will expedite the work of calculation,
and for any ordinary case is sufficiently
accurate. Where greater accuracy is de-
sired the formulas (I) and (2) and the
values of C, and Cz from Table 1 may
be used.

Sulzer Brothers, of Winterthur, Swit-
zerland, have taken out a patent for a
governor for steam engines, more par-
ticularly steam turbines, which is op-
erated by the pressure induced in a
working fluid fas oil) by a small cen-
trifugal or impeller pump, run directly
from the turbine shaft. The oil is fed to
the pump at constant head, an overflow
being provided to insure this constancy,
and the pressure, depending directly up-
on the velocity of the direct-connected
impeller, is made to control the valve
which governs the admission of steam
to the turbine.

exclusion of a proper volume of exhaust
steam. This arrangement was, of itself,
sufficient to keep the heater from doing
its best work. To make matters worse,
the apparatus was further handicapped
by a direct overflow connection to the
same sewer that received the discharge
from a pneumatic sewage ejector; the
overflow valve was never tightly closed

frequently failed to heat the water, the
temperature of which was often as low
as 60 or 65 degrees — practically the tem-
perature of the supply main.

The performance of this heater was
one of the first things noted by a chief
engineer newly arrived on the job, and
the alterations he made to bring it up
to a proper standard of efficiency were
quite simple, but decidedly effective.
These changes are shown in Fig. 2, and
comprise an air vent and a loop inserted
in the overflow pipe to form a water seal.

This work was done in the summer
time, when an ample volume of exhaust
steam was always available for heating
the feed water and the vacuum-heating
system was out of service. The ad-
vantage to the apparatus was immedi-
ately apparent; for. while the daily aver-
age of feed-water temperature thereto-
fore had been about 155 degrees, which
average, however, was based upon a
series of individual readings covering a
wide range, it promptly went up to ap-
proximately 208 degrees Fahrenheit.

Regarding the proposition from the
theoretical standpoint of 1 per cent, sav-
ing of fuel for each eleven degrees gain
in the temperature of the feed water, the
temperature increase indicated above

^1 1 V

i i _1""1

ti=

Fic. 1. Original Pipe Connection to the Heater

on account of a single float doing the
double duty of controlling the inflow as
well as the overflow, the two valves be-
ing connected through a system of levers.
The unimpeded overflow passage thus
arranged simply afforded a convenient
channel through which the air already
lodged in the heater by natural entrain-

should have shown a saving of 4.82 per
cent. As a matter of fact, the daily coal
consumption showed an actual per cent.
reduction very close to this value, the
calculation on both sides being reduced
to a uniform basis of heat energy con-
sumed per unit weight of water evap-
orated.

August 15, 1911

P O W E R

267

Another very excellent device adopted,
and one which also had a direct in-
fluence in establishing a practically uni-
form heater temperature at the highest
point, but at a time when the entire

Piping Hot-water Heaters

I have found the usual practice in
hot-water heating for baths, etc.. to be
that of running the hot water, or high-

^^^^^^mm^^m:

Fic. 2. Showing Changed Piping

W/.

volume of exhaust steam was utilized
in the heating system, was the substitu-
tion of needle valves for the ordinary ' <-
inch gate valves previously used to con-
trol the flow of injection water to the
vacuum pumps, and the installation of
thermometers in the discharge pipes from
these pumps.

This improvement was of particular
value to the engineer on watch as he
could intelligently adjust the quantity
of injection water to varying conditions,
the discharge from the pumps being main-
tained constantly at 190 degrees, thus con-
serving the heat of the returns as well
as economizing the water consumption.
With the old arrangement, the only re-
course was to open the 'j-inch gate valve
a few turns and trust to luck for the rest.

One other adjunct which the new chief
deemed necessary, and one which greatly
benefited the plant, consisted of a float-
controlled automatic valve for admitting
the make-up water. The outfit was al-
ready equipped with the customary over-
head air-separating tank for receiving the
discharge from the vacuum pumps, hut
the above mentioned accessory had been
omitted, and an ordinary globe valve,
manipulated by the fireman, had been
used instead.

As the regulation of this valve solely
depended upon the fireman, it is easy to
understand that there were times when
considerable heat energy, as well as good
city water, was going to waste through
the overflow to the sewer.

A. J. Dixon.

Chicago. III.

est water connection of the heater, to
the bottom or side of the reservoir, and
the cold-water connection on the heater
is made in a similar manner. This does
not appear to be the best plan for good
service.

Hot water is lighter than cold water,
and, therefore, tends to rise to the high-
est point of the reservoir. If it mixes
with cold water as it rises, it requires
a long time before one is able to get
any hot water at the faucet; that is, all
the water above the level of the pipe
must be heated to using temperature
before the system is of service.

The hot-water connection should be
made to the highest point of the reser-
voir and the cold-water connection to
the lowest. When connected in this way,
with the supply to baths, etc., taken from
a high point on the reservoir, or from a
tee connecting the reservoir, hot-water
connection and supply to baths, etc.
^which is the better arrangement), one
may get hot water in a few minutes
after the fire is started. Whatever hot
water there is will be in the top of the
tank and may be drawn direct by the
user; and it is soon supplemented with
hot water from the heater.

The supply water from the system
shniild enter the bottom of the reservoir
or heater, preferably into a tee in the
cold-wafer connection.

I have had the hot-water connections
fill with lime or scale, and consider this
dangerous as I know of two heaters that
burst from this cause, one wrecking the
room above it. If also pays In quick

service, and in a saving of fuel to keep
the heaters clean.

Roy V. Howard.
Tacoma. Wash.

Engine Wrecked at Morgan-
tow n, W. \ A..

On Wednesday evening. August 2. at
the Sabraton works of the American
Sheet and Tin Plate Company, Morgan-
town, W. Va., the engineer was almost
instantly killed by the piston rod break-
ing in the crosshead at the eye through
which the key passes to hold it in the
crosshead. The engine, which was a
Corliss 36x60 inch and made 30 revolu-
tions per minute, was used to drive five
hot mills. The piston rod, which was
6' J inches in diameter, knocked out the
cylinder head and the upper left corner
of the cylinder, the break plainly show-
ing it had been cracked for some time.
The engine was installed in a concrete
pit about 5 feet deep, beside an exact
duplicate. The engineer had just come
on duty, had gone over his engines and
was sitting down back of them and to
one side when the accident occurred,
throwing him a distance of 20 feet.
From the effects of the scalding and
bruising he received, the engineer died
on the way to the hospital.

liducational Program of
Modern Science Club

On September 26, from 7 to 10 p.m.. a
beefsteak dinner will be held in the grill
rooms of the Modern Science Club, 125
South Elliot place, Brooklyn. An ex-
position and discussion of the proposed
winter courses of study will follow.

In addition to the regular Tuesday
night lectures the proposed educational
program for the season of 1011-12 will
consist of two courses of 30 lectures,
each embracing subjects bearing direct-
ly on the vocation of steam-engine op-
eration.

Beginning Friday, October 6, the first
course will treat of mathematics for
engineers, such as fractions, decimals,
percentage, square and cube root, equa-
tions, the slide rule, natural philosophy
and graphical statics.

On Monday. October 0. the second
course begins. It will consist of lectures
on fuels, their origin, nature, character-
istics and analysis; steam, its generation
and distribution in engines, puinps and
turbines, theory and practice in the use
of condensers, including their design and
installation; steam-cncinc design and
operation; thcopi' of the turbine, both
impulse and reaction; the indicator and
its application; the slide-valve diagram
and its value in steam-engine design:
internal-combustion engines, InctudlnR
gas producers; flue-gas analysis and
general engine- and boiler-room chem-
istry.

P O W K R

August 15. 1911

Richardson Si^^ht Feed Me-
chanical Lubricator

This lubricator is designed to supply
oil to a cylinder just as it is required.
The oil is fed drop by drop from the
feed nozzles at any rate desired and is
broken up into a number of small par-
ticles which are mixed with the steam
entering the cylinder.

Each lubricator contains an oil reser-
voir, and a gage glass which shows the
oil level. The pump body is made from
a solid block of iron drilled out to re-
ceive the interior mechanism. The pump-
ing plungers are made of polished-steel
drill rod, working in die-molded babbitt
bushings. The plungers are actuated by
a common gear shaft that is operated
from a driving lever which is connected

fVhat the in-
ventor and the man u -
facturer are doing to save
time and money in the en-
0ne room and power"
house. Engine room
news

foot valve A, Fig. 1, by means of the
plunger B, delivering the oil through the
circulating channel C, into which are
connected the adjustable needle valves
M M, etc., for regulating the flow of oil
through each drip nozzle R, Fig. 2.

All surplus oil not passed through
the feed valves returns to the reservoir
through the overflow ball check D, Fig.

ways full of oil up to the check valve
N, located at the point of delivery; thus
every time the pump plungers descend
they force a small particle of oil into the
line, and release a corresponding amount
at the terminal check valve. As the oil
is forced through two check valves KK
and a terminal check valve A^, there is
no liability of steam pressure backing
up into the lubricator. The check valves
are of a special steel-ball type, and are
held in place on a bronze seat by a coil
spring under a hexagon nut. The babbitt
bushings F can be quickly taken up for
wear by removing the hexagon cap nut
W and slightly tightening up the valve
cage U.

An important feature is the increased
feed valve P located in the oil-circulat-
ing channel C. This valve is normally

c f^

I ;| — T n Tr J

=r' V R R R-

Fig. 2.
Three Views of the A'Iodel "M" Mechanical Lubricator

to any convenient reciprocating part on
the engine.

The operating mechanism runs in oil,
almost entirely eliminating wear, and
there are no projecting screws, nuts,
ratchets, glasses under pressure or by-
pass devices.

The operation of this lubricator will
be made clear by referring to the accom-
panying diagram, in which the travel
of oil from the reservoir to each in-
dividual feed line is shown. The oil
is withdrawn from the reservoir through

1. The slight gravity head on each drip
nozzle is constant, and the oil flows drop
by drop at any desired rate into the
chamber G, Fig. 3. The plungers for each
individual feed line are actuated by the
driving lever through a common gear
shaft H. These plungers move up and
down with every revolution of the en-
gine and at each downward stroke chop
off a small particle of the oil protruding
from the chamber G and force it out
through the check valves K K and into the
feed lines L. The feed lines are al-

left open, but it can be closed should
there be a temporary demand for in-
creasing the amount of oil fed by shut-
ting off the return to the reservoir and
causing all of the oil delivered by the
circulating plunger to flow through the
feed nozzles, thus temporarily forcing
the flow of all feeds. When the increased
demand has been met, the increased feed
valve P is opened. Thus the adjustment
of the needle valves A! need never be
changed to meet a temporary demand for
additional oil.

August 15, 1911

POWER

269

f^^H^'^^^^pI

Fig. 4. A Four-feed Lubricator, Showing Pipe Connections to Engine

The driving lever ] requires a recipro-
cating movement of from 72 to 96 de-
grees and can be moved into any position
on the shaft. The necessary travel of
the lever / can be adjusted by attaching
the driving-rod pin in any one of the
eight wristpin holes 1', thus permitting
any straight-across travel from 3 7 '16 to
8'/< inches.

The glass protecting the feed nozzles
is not under pressure, being held in posi-
tion by a spring-retained brass frame
which can be easily tipped forward for
cleaning the nozzles.

This lubricator can be applied to any
vertical, horizontal, simple or compound
steam engine, and to all types of gas
engines, ammonia compressors, high-
duty pumping engines, air compressors,
pumps or any machinery where it is
desired to feed a predetermined amount
of oil against pressure.

In Fig. 4 is shown the application of
a four-feed lubricator, one oil pipe con-
necting to the steam pipe, two to the
steam valves, and one pipe is led to
the piston-rod metallic packing.

A pump having 22 feeds is shown in
Fig. 5. It is used for automatically
lubricating the bearings of high-duty
elevator pumps or wherever a number

of bearings are to be lubricated. These
pumps are manufactured by the Richard-
son-Phenix Company, Milwaukee, Wis.

Hopewell \'ihrac;itor

A device for detecting knocks in an
engine is shown in the accompanying
illustration.

The head of the vibracator consists of
a hardened-steel corrugated diaphragm
that is made as thin as i' is possible to
draw the metal. The vibrations of the

HoPEvcELL Vibracator

machinery are transmitted to the dia-
phragm which sets up vibrations in the
air inclosed in the head and the amount
of the air inclosed in the head is small,
giving only necessary clearance for vi-
brations. These vibrations are trans-
mitted through the air up the tubes into
the ear tips and thence to the ear. The

ear tips are held in position by springs
inclosed within the rubber tubes. The
diaphragm head is insulated on to the
rest of the body by nonabsorbent ma-
terial so that the vibrations are trans-
mitted directly to the air.

The device is manufactured by Hope-
well Brothers. Newton, A\ass.

Loose Pulley Oil Cup

The accompanying sectional view illus-
trates an automatic loose-pulley oil cup
which will run from one to three weeks
when filled once, according to the ni^-
ber of starts and stops, speed, etc.

As the pulley is brought into opera-
tion the centrifugal force throws the oil
to the top of the cup and fills the feed-
ing tube. When the pulley starts the
next time a portion of the oil in the
tube is fed to the bearing and the tube
again fills with oil.

Fig. 5. A Twenty-two Feed Force Pump

Loose Pulley Oil Cup

The cup can be detached by hand from
the nipple and can be removed, filled
and replaced with the pulley in any
position.

The cup is made of thin pressed steel
by the American Specialty Company,
Chicago. 111.

To drive the machinery in a table and
furniture factory in Schoharie, N. Y..
two waterwhecls have been installed on a
small creek. In addition, the proprietor
not only lights his house and factory, but
a neighboring church and the main vil-
lage street. This is but one of many
instances where the high cost of fuel has
caused the small user of power to utilize
the natural advantages near at hand.

270

PERSONAL

G. H Gleason has become vice-presi-
dent of the Dexter Engineering Com-
pany, Incorporated, Providence, R. 1. He
was formerly engineering salesman of
the Dodge Manufacturing Company, Bos-
ton, Mass.

Prof. Carl C. Thomas, of the Uni-
versity of Wisconsin, is now in Europe
conducting some interesting investiga-
tions along engineering lines. It is his
intention to remain on the continent
until the summer of 1912. All corre-
spondence should be addressed in care
of Knauth, Nachod & Kiihne, Leipsic,
Germany.

Frank J. Wood, chief engineer for
Marx & RawoUe. at Brooklyn, N. Y., is
the first recipient of the gold medal
awarded by the American Institute of
Chemical Engineers for the best paper
presented to the society. 5ucn medals
are to be awarded every three years,
and Mr. Wood earned the first by the
presentation at the Philadelphia meeting
in 1909 of a paper upon "Glycerin Re-
fining in Multiple Effect Stills." Mr.
Wood is a prominent member of the N.
A. S. E. and of the Modern Science
Club, of Brooklyn, of which he was
president for a number of terms.

Alonzo Pawling, president and treas-
urer of the Pawling & Harnischfeger
Company, Milwaukee, and for many
years a prominent figure in the machin-
ery field, has disposed of his interests
in the company and retired from busi-
ness life.

In December, 1884. Mr. Pawling, to-
gether with Henry Harnischfeger,
founded the Pawling & Harnischfeger
Company, under the firm name of Pawl-
ing & Harnischfeger. From a small be-
ginning the concern has grown to large
proportions.

Mr. Harnischfeger becomes president
and treasurer of the company; W. H.
Hassenplug, vice-president; F. P. Breck,
second vice-president, and S. H. Squier,
secretary. There will be no changes in
the policy of the company or in its or-
ganization.

POWER

In 1881 he entered the Sheffield
Scientific School of Yale, graduating with
the class of 1884, and worked as an ap-
prentice in the shops of the Pennsylvania
Railroad Company at Altoona, Penn.,
during the two summer vacations. From
1884 to 1885 he was an apprentice at
the West Milwaukee shops of the Chi-
cago, Milwaukee & St. Paul Railroad,
and then went to the Chicago, Burlington
& Quincy Railroad Company as a drafts-
man in the mechanical engineer's office,
later becoming assistant engineer of
tests, and finally engineer of tests. From
1887 to 1889 he was superintendent of
telegraphy, and from 1889 to 1890 was
division superintendent of this road.

From 1890 to 1892 Mr. Herr was divi-
sion master mechanic of the Chicago, Mil-
waukee & St. Paul Railroad at West
Milwaukee which he left to accept the
position of superintendent of the Grant

Edwin M. Herr, who was elected presi-
dent of the Westinghouse Electric and
Manufacturing Company at a meeting of
the board of directors held in New York,
August 1, has been the first vice-presi-
dent of the company and in charge of
operation at East Pittsburg since June
1. 1905.

He was born in Lancaster, Penn., May
3, 1860, and upon completion of a com-
mon-school course, became a telegraph
operator on the Kansas & Pacific rail-
road, with which company he remained
for two years, being promoted to the
position of station agent.

Edwin M. Herr

Locomotive Works at Chicago. After
remaining in this capacity for two years
he became superintendent of motive
power and machinery of the Chicago &
Northwestern Railroad, and from June
1, 1897, to September 10, 1898, held the
same position with the Northern Pacific
Railroad.

In 1898 he became assistant general
manager of the Westinghouse Air Brake
Company and the following year was
promoted to the position of general man-
ager, which position he held until June
1, 1905, when he was elected first vice-
president of the Westinghouse Electric
and Manufacturing Company.

The other officers elected by the board
of directors of the Westinghouse Elec-
tric and Manufacturing Company to
serve with Mr. Herr were: Chairman of
the board of directors, Robert Mather;
vice-presidents, Loyall A. Osborne,
Charles A. Terry, Harry P. Davis; act-
ing vice-presidents, Henry D. Shute,

August 15, 1911

George P. Hebard; comptroller and
secretary, James C. Bennett; treasurer,
T. W. Siemon; auditor, F. E. Craig.

SOCIETY NOTES

A special train will take the New Eng-
land and New York delegates and vistors
to the convention of the National As-
sociation of Stationary Engineers at Cin-
cinnati. This train will leave Boston on
Sunday, September 10, about 10 a.m.
and another leave New York over
the West Shore Railroad at 2:30
p.m. The Boston train will stop
at Worcester and Springfield; the
New York tram at Highlands, New-
burg and Kingston. The two trains will
be joined at Albany and from that point
proceed to Cincinnati, stopping pt Syra-
cuse, Rochester and Buffalo. Reserva-
tions and further information about the
train may be obtained from James R.
Coe, chairman of the transportation com-
mittee. 21 .Maiden Lane, New York City.

BOOKS RECEIVED

Pumping Machinery. By Arthur M.
Greene. John Wiley & Sons, New-
York. Cloth; 703 pages, 5 '_.x9 inches;
504 illustrations; indexed. Price, S4.

Experiments on the preservation of
Westphalian coal under exclusion of air
have been carried out by Dobbelstein,
and are described in Gliick Auf! of May
6. The coal consisted of lumps about
.' ! inch in size and vessels of about ' .•
gallon capacity were charged with this
coal and provided with air-tight covers.
The vessels were further filled, either
with water or with carbon dioxide, flue
gases or sulphurous acid vapors. Sam-
ples were taken and analyzed after two
weeks, three weeks and six months; at
the end of this period no further weather-
ing seemed to occur. Parallel tests were
made with coal exposed to the air. The
different sorts of coal did not all behave
equally. But on the whole it would ap-
pear that little is gained by keeping the
coal under water or in special atmos-
pheres. The loss of gas was little af-
fected by the treatment, and the differ-
ence observed might have been less
noticeable if the coal had been taken
as soon as mined, and not after inter\'als
of from five to eight days; the weather-
ing is most marked in the first days. If
anything special is to be done for the
storage of coal, roofs should be provided
for the coal piles, and thermometers be
inserted so as to obtain warning of any
tendency to spontaneous combustion. —
The Engineer.

A boiler explosion at one of the Pitts-
burg mills of the Crucible Steel Com-
pany of .\merica on August 2, injured
three men and damaged property to
the extent of SI 0,000.

17'

\'ol. U

M.W ^ORK, AKjUST 22, T^l

No. 8

E\'ERV little while some "earnest friend of labor"
or a cream-colored newspaper emits a howl that
the heel of Capital is on the neck of the mechanic,
and a few employers will whine that the unreasonable
and work -shirking employee is getting all the profits
and the boss will have to sell one of his six automo-
biles or go in arrears on his alimony to keep the wolf
from the door.

Of course these are the opinions of pessimists and
should be considered as such.

The successful business man knows that highly
trained commercial skill is necessary to his success,
and the mechanic is beginning to realize that his skill
is a large factor in his employer's success.

They must both pull in the one direction if their
efforts are to count for much.

Because of competition the business man has to be
aggressive, and the same line of reasoning holds in the
engine room.

Too manv engineers lack confidence in their ability
to do things !

When the old man engages an engineer to run his
plant he says in effect:

"Vou are supposed to
know your business. I won't
be satisfied with youi just
keeping things a-goin", I
want results. I want econ-
omy, efficiency and out-
put.

" You save my money
and I'll increase your
wages. I'm hiring your
hranu as well as your
brawn ; now set 'em at work.
I'll meet vou half way."

It pays to be aggressive these days, when, you can
back it up with a sound, practical knowledge of your
vocation.

Many an otherwise competent engineer has been
kept back because he lacked confidence — because he
was afraid to open his mouth after he had a strangle-
hold on a good idea and then let go before both shoul-
ders were on the mat

The engineer must "advertise his wares" and let the
(jtiality of his work do the rest.

A business man with a salable article does not stow
it away on the top shelf of his shop and wait for a
customer to suggest that it might be of use if it were
brought into view.

He advertises it, makes it known. And, what is of
most consequence, he sells it at a profit.

Treat your \ocation as a business and ask yourself
if your "salable article" is poked away on the top
shelf of your brain. If so, pull it down, weigh it up;
then if you find it is practical and profitable, let the
old man know about it. Ten to one your idea will go
through and you will have gained just that much pres-
tige in the eyes of the boss.

Your Uncle Sam has a large and growing family,
and the "boys" who arc
going to reflect credit on the
old man's "bringin' up" arc
the ones who are equipping
themselves with a gotxl
working knowledge of their
vocation.

"Vou can't keep a goorl
man down!" said Jonah as
he «Tenchcd himself from
the belly of (he whale.

.\nd the whnle doubtless
agreed with Jonah even if
Jonah disagreed with the
whale

POWER

August 22, 1911

Modern English Power Plant

In tlie April 18 issue were given the
results of some record-breaking tests
upon one of the turbines of the Dunston
power station of the Newcastle-on-Tyne
Electrical Supply Company, ,the best
performance being a steam consumption
of 11.8 pounds per kilowatt-hour.

In view of these results we believe
a description of this new and thoroughly
uptodate plant will be of interest to our
readers, for much of which information
we are indebted to our contemporary,
Engineering.

The present rated capacity of the plant
is 23,000 kilowatts, space being pro-

A description of the 23,000-
kihnvatt plant recently com-
pleted at Dunston for the
X ewcastle-on-Tyne Elec-
trical Supply Company.
One of the turbines of this
pla)it holds the record for
hnv steam consu7nption.

corrugated iron, very little brick being
used in the construction.

Boiler House

The ultimate plans call for two boiler
houses and two coal-storage pockets,
one boiler house and its corresponding
storage pocket supplying two turbine
units. At present, however, there is but
one boiler house and one storage pocket
which supplies the three turbine units
now installed.

The equipment consists of eight Bab-
cock & Wilcox marine type of boilers
set in batteries of two. Each batterj-

Circulatinrj Pump

Fig. 1. Longitudinal Section through Dunston Power Station

Fig. 2. BoiLER-UduM Aisli:

vided for an additional unit of 7000 kilo-
watts. As shown in Figs. I and 2. there
are three distinct buildings, the coal-
storage pocket, the boiler house and the
engine room, the boiler house being

situated between the other two. In ad-
dition there is the switch house, an in-
dependent structure located at some dis-
tance from the main group. The build-
ings are of steel framing sheathed with

is served by a chimney, an induced-draft
fan and two economizers. There is one
main steam pipe, feed-water pipe, hot-
well, feed pump and ash conveyer for
each set of four boilers.

The boilers are fed by chain-grate
stokers and are provided with super-
heaters, each battery of two boilers be-
ing capable of furnishing, under norma!
conditions. 60,000 pounds of steam at a
pressure of 200 pounds gage and a tem-
rerature of 572 degrees Fahrenheit.
Fig. 2 is a view looking down the aisle
between the rows of boilers.

Coal and Ash Handling

Coal is dumped from cars to a re-
ceiving hopper (see Fig. 1), through a
crusher and screen into an automatic
filler. This discharges onto a continuous
conveyer which runs over the storage
pockets, over the bunkers located above
the boilers, and down at the far end of
the boiler room, then back under the
boilers and storage bins. Thus coal may
be discharged from the cars direct to
the storage bins, direct to the bunkers
over the boilers or from the storage bins
to the boiler bunkers. This conveyer
is capable of handling 40 tons of coal
per hour.

The ash-handling equipment is dis-

August 22. 1911

POWER

tinct from the coal-handling plant, and
consists of hand-propelled dump cars

Main GENERATtNC Units citers direct connected to the turbine

These consist of two 8000-kilowatt shaft.

The voltage regulation of the Brown.

running on tracks below the boilers and Allgemeine Elektricitats Gesellschaft tur-
receiving the ashes direct from the boiler bo-generators and one 7000-kilowatt Boveri & Co. machine is as follows:

When generating at 5750 volts the throw-

\ jj^>^--cJF-_^j^ .-," ."TT^'fri'^^?^^^'^ Cables to Switch Housed-

ing off of a noninductive load of 553
amperes causes a rise not exceeding 10
per cent., the speed and excitation re-
maining constant; and in throwing off

Fig. 3. Plan of Generating Station

ash hoppers. These tracks lead to a
hoist which lifts the cars to a suitable
hight to permit their contents being
dumped into an ash bunker, located be-
tween the boiler room and the coal
pocket. This ash bunker, in turn, dis-
charges into gondola cars which carry
the ashes away from the plant.

Steam Piping

From each of the two rows of boilers
a steam main leads to its own receiver
on the turbine-room floor, and from the
receiver, pipes run to the steam sep-
arator, thence to the turbine stop valves.
The two steam receivers are connected
beneath the floor by a U-bend.

The steam pipes are of solid drawn
mild steel with forged-steel flanges,
pipes of 7 inches and greater having their
flanges riveted; the smaller pipes have
screwed flanges.

The feed piping is in the form of a
complete ring divided by means of iso-
lating valves into separate sections for
each boiler; hence each economizer can
be fed from either of two adjacent sec-
tions, or each boiler can be fed direct
from the main when the economizer is
cut out of service.

The feed pumps are located in the
engine room and are thus removed from
the dirt of the boiler room.

Fig. 4. Turbink Room

Brown. Boveri fi Co. Parsons type of
tf rbo-cenerator. Each machine produces
three-phase currents at 40 cycles and ap-
proximately .'i7.''0 volts. In each case ex-
citation is furniihed at 220 volts by ex-

a load of 628 amperes with a power
factor of O.P the rise in voltage docs
not exceed 20 per cent. The exciting
circuit is so arranged as to allow the
generator voltage to be raised from 5000

274

POWER

August 22, 1911

volts at no load to 5750 volts at a load
of 7000 kilowatts. This is the machine
which showed the remarkable economy
heretofore referred to.

The turbine governors of the Allge-

Electrical Equipment

All the high-tension switching equip-
ment is contained in a separate building,
the only high-tension switches in the

'.'■•FeederSide'-:' A:-V--"v.i";'::-.v:'.':r, " ' " "Genera+or Side'

Fic. 5. Section throlgh Switch House

meine Elektricitats Gesellschaft machines
are arranged so that the speed may be
varied 5 per cent, above or below nor-
mal. A safety governor on each machine
cuts off steam when the speed exceeds
1320 revolutions per minute.

Surface condensers are employed, cap-
able of condensing 80,000 pounds of steam
per hour while maintaining a vacuum
of nearly 29 inches. The circulating
pumps are located in pits below the level

engine-room being an emergency gear
near each generator for tripping the
main generator switches, with which is
also interlocked a field switch.

The switch house is a 135x33- foot
two-story building. The control room,
containing the operating boards, is on
the first floor as are also the disconnect-
ing switches, potential transformers, etc.
The main oil switches and busbars are
on the second floor. A section through

Fig. 6. Con-rol Hl

of the river and are driven through ver-
tical shafts by three-phase motors
mounted on the engine-room floor. These
pumps will deliver 450,000 gallons of
condensing water per hour.

The air pumps are of the three-throw
Edwards type driven by three-phase
motors.

A general view of the engine room is
shown in Fig. 4.

the switch compartment is shown in
Fig. 5.

The control gear is operated by di-
rect current at 100 volts supplied by
two storage batteries. A view of the
control room is given in Fig. 6.

The direct-current switchboard, con-
sisting of a 100-volt power and lighting
panel and 500-volt traction panels, is
located in one corner of the engine room.

. Cost of a Power House

By A. E. Dixon

Following is the building cost for a
plant of 1600 kilowatts capacity which
was constructed not long ago in one of
the Middle Western States:

Bl'ilding-cost Figures

Per i Per
Kilo- .Square
Foot

Steel work, roof truS'

ses, beams, etc

llasonr.v. miscellan-

eoiis. etc

Labor for construction
Light ing. wiring and

material

I.abr>r. erecting light

ing raalLTiai, etc. .

948.18
234.21

§38,818.21

0.593
0.146

S24.469S2

0.058
0.014

The building to which the foregoing
costs apply covered an area of 16,500
square feet and was originally designed
to contain four 400-kilowatt direct-cur-
rent generators direct connected to Cor-
liss engines. The boiler room was laid
out originally for eight 325-horsepower
boilers but afterward the size of the
boilers was changed and 400-horsepower
units were used in the first batter>' in-
stalled. The engine room was spanned
by a 20-ton crane. The original engine
and generator installation was one unit
of 400 kilowatts capacity; and later a
750-kilowatt horizontal turbine was in-
stalled.

The plant was designed by a firm of
w^ell known consulting and contracting
engineers and the cost per square foot
of area covered is not at all high. How-
ever, it might be considered that a ver>-
long look into the future was taken in
providing space for extension to 1600
kilowatts capacity. The space allowed
in this plant was extremely liberal, 10.3
square feet per kilowatt, and does not
compare very favorably with plants of
approximately the same size having from
4 to 5 square feet per kilowatt without
undue crowding of the apparatus.

This particular plant was favorably
located on good, sandy soil, close to a
permanent water supply. Excavation
was cheap and the other local conditions
were favorable. In many cases the
foundations below the ground line have
cost from 25 to 35 per cent, of the total
cost of the structure. Where founda-
tions are very expensive they may some-
times run as high as 50 per cent, of the
cost; this, however, is an extreme con-
dition and rarely occurs where there is
any choice in the location of a site for the
plant.

In many of the larger steam plants
the cost of the building per square foot
is much higher than the figure for this
plant, ranging from 55 to SlO without
foundations, the higher costs applying
to those plants having overhead coal
bunkers or double-decked boiler rooms.

August 22, 1911

P O \lt' E R

275

The Design of Steam Power Plants

-

m

Superheat, ^-tn i/aci/um

H

^

-~L 1 ' ' '

__

—

_

Steam Turbines

When deciding between a reciprocat-
ing engine and a steam turbine the fact
should not be overlooked that each pos-
sesses certain advantages over the other
for a given service ; hence the service
for which the prime mover is intended,
and the conditions of operation, should
be carefully considered.

In large central stations the adoption
of steam turbines effects a saving in
the cost of the building, besides requir-
ing lighter and smaller foundations than
engines of the reciprocating type; this
saving often amounting to from 10 to
15 per cent, of the total cost of the
building. Also, with the advent of the
steam turbine a new arrangement of
power plant has sprung into existence
in which the turbines are located on a
floor above the boiler room, the station
of the Fort Wayne and Wabash Valley
Traction Company at Fort Wayne, Ind.,
being a good example of what has been
done in this line.

-I'3j

II

5000 6000 7O0O 8000 900O KjOOO lljOOO 12000
Load m Kilowa*»s "''*"

Fic. 1

Lubrication

Another point in favor of the steam
turbine is that it requires no internal
lubrication as the only rubbing sur-
faces to be lubricated are the main bear-
ings. Therefore, oil does not come in
contact with the steam and the con-
densation may be used over again for
boiler- feed purposes without the neces-
sity of separators, etc. This results in
a saving in feed water and the expense
incurred in cleaning heaters and boilers.

Besides the lubrication of the guide
bearings, steam turbines of the vertical
type require oil or water under a pres-
sure of several hundred pounds per
square inch in the step bearings, to bal-
ance the weight of the revolving ele-
ment. This requirea a high-pressure
pump and extra-heavy piping.

Saving in Floor Space

It is claimed that the vertical-shaft
turbine occupies only about one-tenth as
much floor space per horsepower as a
reciprocating engine of the same output,
but in this respect the floor space oc-
cupied by the condenser, air pump, hot-
well pump, circulating pump, etc.. should
be taken into account as they frequently
occupy more floor space than the tur-
bine itself. The necessary clearance

By William F. Fischer

In tin's instalmciti tlic
adaptability of the steam
turbine for varioris classes
of service is considered
and its chief characteristics
are noted.

around each of the auxiliaries should
also be considered.

Following is a comparison of the
amount of floor space occupied by sev-
eral prime movers of approximately 2000
electrical horsepower, normal rating.

Squan*
Foot prr
Horsepower
Horizontal cross-compound Corliss en-

gine.s 0 61

Vertical eross-cornpound Corliss engines 0.36
Weslinghouse-Pareons sleain turbines. 0.146
Curtis liorizontal steam turbines 0 O'JS

22

1 I ill

/

Engme »■

Ih Equal Work

/

1

'"

Cyl,

nao

^i(/

^

I

y

^

y

,

1

S^

1 — '

^

-^-tr

'witli Unequal

V,J

I

u"

— \ WirkmCfhn

III

der-

1-

—1

Steam Turbine

_

1 1 1 1 1

3)0030004000 50006000 7000 80009000
L^ad in Kilowotts ""'

Fic. 2

The approximate floor space per elec-
trical horsepower for large units is:

.Squan"

Koql per

Horsepower

Horizontal vertical cross-compound
Corliss engines, Manhattan type,
.5000 to 8000 horsepower 0. 48

Vertieal three-cylinder compound
Corliss engines, .5000 to 8000 horse-
power 0.2

Wisl inuliouse-Parsons steam turbines,

.'.ODil to 8000 horsepower 0,1

C'urli> hi>rizontal steam Mirbines, 5000

to sddii horsepower 0 06

Ciirlls viitiral .steam turbines, .50(K) to

S(M)il horsi'pow.T. , . 0 01

The foregoing are based on the over-
all dimensions of the generating units
and do not include condensers or auxil-
iaries.

Economy of Reciprocating Engines
and Steam Turbines

Many stations handle a variable load;
hence high economy at all loads is a
very desirable feature. One of the prin-
cipal claims of the steam-turbine build-
ers is its relatively high steam economy
at other than rated loads, whereas in
the best-designed reciprocating engines
the best all-round economy Is obtaiticd
at one point only, the cutoff occurring
cither too early or ton late at other loads,
for the cylind.cr proportions.

Fig. I shows the results of a test on
a 9000-kilowatt flvc-stage Curtis turbo-
generator runnl.re at 7.S0 revolutions per

minute and at a steam pressure of 200
pounds gage, with 125 degrees super-
heat and a 29-inch vacuum. The load
curve is almost flat and shows a high
economy at all loads from 6000 to 12,000
kilowatts; at loads below 5000 kilowatts
the economy falls off rapidly.

Fig. 2 illustrates the economy of a
5000-kilowatt Curtis turbine as compared
with a 5000-kilowatt four-cylinder com-
pound engine. Both machines were op-
erated under similar conditions with a
steam pressure of 175 pounds gage and
saturated steam.

The extreme overload capacity in
favor of the steam turbine is an im-
portant factor in central-station service
where there is apt to be one or more
sharp peak loads of short duration, such
as frequently occurs during a thunder
shower.

Vacuum, Steaa^ Pressure and Super-
heat
While it is not absolutely necessary

-l50lb.BoilerVressurvJI?00 R.p.
. /, Dnf SoTunjted Steam, dS'^'acuurT.

■ 5.- /OOpe^rees Superheaters V<gc.

Brake Horsepower

Fic. 3

to use a high vacuum with a steam tur-
bine, it is desirable to do so to obtain
advantage of the higher economy made
possible thereby. Steam turbines can
use a high vacuum to much better ad-
vantage than the reciprocating engine,
and show a much greater increase in
economy.

As a rule, any increase in vacuum
above 26 inches adds but little to the
economy of the reciprocating engine, as
it is not adapted to handle the large
volumes of steam due to the lower pres-
sure and the increased cylinder con-
densation caused by the low-pressure
steam would offset any gain resulting
from the additional expansion.

Fig. 3 gives the economy of a 1250-
kilowatt Westinghouse-Parsons turbine
in terms of pounds of steam per brake
horscpowcr-hour, operating with a vac-
uum of from 25 to 28 inches.

The gain in economy by operating a
steam turbine at a vacuum higher than
28 inches does not usually warrant the
expenditure of the additional money nec-
essary for the better class of condensers,
pumps, etc., required to produce higher
vacuum.

The steam pressure usually carried
on steam turbines varies from 150 to 200
pounds gage, and the steam is usually

27(5

POWER

August 22, 1911

superheated from- 100 to 200 degrees
Fahrenheit above the temperature cor-
responding to its pressure. As far as
the total overall station economy is con-
cerned, there is not much to be gained
by increasing the pressure or superheat
above the figures given.

The construction of the steam tur-
bine permits the use of highly super-
heated steam as the turbine requires no
internal lubrication and there are no in-
ternal rubbing or wearing surfaces,
whereas the difficulties experienced with
lubrication and the destruction of valves,
glands, etc., under high temperature
limits the use of superheated steam with
all engines of the piston type.

Fig. 4 shows the water rate of a 1500-
Icilowatt four-stage Curtis turbine op-
erating at 150 pounds gage pressure with
a 28-inch vacuum. The upper curve
shows the steam consumption in pounds
per kilowatt-hour operating with dry
steam, and the lower curve the steam
consumption with the steam superheated
125 degrees. The saving is due both to
the maintenance of drier steam at tliL

|21

-1 20

^

N

150 lb. Gage

„ 1 1
Pressure,

V

^

I ZS ir

. Vacuum
1 1

t

1 Q^^sU

1 1 1

^^<.^..l, 1

~T~-

1

— r^rS

;* 1

1

^ 1 ~t

400 500 600 700 800 900 1000 1000 IfflO 000 MOO 1500 1600
Load in Kilowatts '""^

FiC. 4

throttle and to a reduction in friction
upon the blades caused by condensation
as the steam expands.

Steam turbines as well as reciprocat-
ing engines should be protected by
steam separators placed in the steam
line near the throttle. These should
be of sufficient capacity to retain all
water carried over by the steam, for
entrained moisture in the steam increases
the water rate to a large extent besides
causing excessive wear on the turbine
blades.

TURBO-CENERATORS AND THEIR REGULA-
TION

Since the introduction of the steam
turbine the general characteristics of
electric-generating apparatus have been
modified to a large extent and rotative
speeds have been increased. This has
resulted in minimum bulk and less cost
of construction so far as is consistent
with strength and durability. A 5000-
kilowatt 40-pole engine-driven generator
running at 75 revolutions per minute is
about 40 feet in diameter and weighs
■approximately 980,000 pounds, whereas
a SOOO-kilowatt 4-pole turbine-driven
generator running at 750 revolutions per
minute is about 12 feet 6 inches in diam-
eter and weighs approximately 234,000
pounds; both machines being 25-cycIe

units with the weights of shafts and
journals included in each case.

The preferable construction for alter-
nating-current generators comprises a
rotating field and stationary armature.
A uniform driving torque is desirable
and this is more easily obtained in steam
turbines than in reciprocating engines
because the forces acting upon the blades
of the turbine are continuous and the
speed of the rotor is uniform, whereas
the variable pressure acting upon the
crank pin of a reciprocating engine makes
necessary the use of heavy flywheels.

Published tests of Parsons and Curtis
steam turbines show an average fluctua-
tion of 2 per cent, from no load to full
load, and 3 per cent, from no load to
100 per cent, overload. Turbine-driven

Veteran Engineer and Engine

It has been written that threescore
years and ten is the span of mortal life.
What the normal span of life for an
engine is no authority has yet laid down,
but certain it is that the engine in this
story has surpassed in number of years
of useful work a great majority of the
engines ever built.

This engine was put into service in
December, 1855, and with the exception
of eight and one-half days during which
repairs were being made on it, has been
in continuous operation ever since in the
plant of the Case Lockwood & Brainard
Company, of Hartford, Conn. The en-
gine was built by the Woodruff-Beach
Company of the same city.

Mr. Lynch and the Ancient Engine

alternating-current generators may be
operated satisfactorily in parallel with
those driven by reciprocating engines,
providing the engine possesses good regu-
lation. The following is from a paper
entitled "Power Plant Economics," by
H. G. Stott, and will serve to illustrate
this point:

"In one of the plants of the Inter-
borough Rapid Transit Company, of New
York City, a steam turbine was thrown
in parallel with a double-compound en-
gine carrying a railway load. The ele-
mentary overloads were carried almost
entirely by the steam turbine, while the
engine load remained practically con-
stant, showing the ability of the steam
turbine to respond quickly to overloads
under the most exacting conditions of
service. In this case the action of the
steam turbine was much like that of a
storage battery."

The only repairs that ever were made
to the engine were a new crank disk and
a new cylinder which were put in dur-
ing 1906. The original crank-pin brasses
were in use for 41 years.

The engine has sotne of the earmarks
of the old timers, with its box bed and
plain crank. At the time it was built it
was the only design of engine having
an automatic-cutoff quick-closing type
of steam valve with the exception of the
Corliss. The valve gear is of the well
known Woodruff & Beach design, pop-
pet inlet and slide-valve exhaust. The
diameter of the cylinder is IS inches
and the stroke is 36 inches; the steam
pressure is 85 pounds, gage, and the en-
gine runs at 55 revolutions per minute.

Mr. C. H. Lynch, the present chief
engineer, took charge of the engine in
1865, after he returned from serving
with the Union forces in the Civil War.

August 22, 1911

POWER

277

A New High Pressure Gas Blower Set

Among the radical modifications be-
ing introduced into the modern gas
works is the raising of the blast pres-
sure about 100 per cent.

In the majority of existing plants the
blowers are operated at a pressure vary-
ing from 20 to 22 inches, but the blower
sets now being installed in the new
plants of the Brooklyn Union Gas Com-
pany, and the Consolidated Gas Com-
pany of New York, are designed for
40-inch pressure.

The object of this change is to mate-
rially reduce the "blowing period," and
thereby increase the number of "making
periods" per 24 hours with the ultimate
result of increasing the capacity of a
given machine. It is estimated that this
increase will not be less than 25 per
cent., and it is anticipated that it will
be nearer 50 per cent. A pressure of
40 inches of water, or nearly 111
pounds per square inch, is quite a new
departure in gas-blower design.

The turbo-blower unit shown in the
accompanying figure consists of a sin-
gle-stage turbine direct connected
through a flexible coupling to a multi-
vane type blower, the two machines
being mounted on a common cast-iron
bedplate. The turbine is of the single-
stage Terry type. The steam is ex-
panded in one step from initial pressure
down to exhaust pressure, thus avoid-
ing the complication of any intermediate
diaphragms and their stuffing boxes, and
the main casing is subjected to exhaust
pressure only.

The glands or stuffing boxes are of
the floating bushing type, kept steam
tight by ground metal joints, eliminat-
ing the necessity of any soft packing.

The speed-regulating governor is
mounted directly on the outboard end
of the turbine shaft, and no possible
failure of any intermediate gear drive
can occur. Running at turbine speed,
the governor is naturally ver\' powerful
and at the same time highly sensitive,
as will be shown by the results of the
regulation tests quoted later.

The two machines are connected
through a flanged coupling, the pins of
which are fitted with sliding sleeves;
thus the thrust of each machine is taken
care of independently, and the end play
of either machine is not transmitted to
the other. Rubber bushings are fitted
to the outside of these sleeves, allow-
ing smooth running with a certain
amount of misalinement of the two ma-
chines.

The blower is of the Sturtevant
double-inlet multivane type and is con-
structed of steel throughout. The blades
are mounted on a solid central disk
carried by the hub, and the outer ends

Rectiit practice in gas
uorks is to increase the
generator capacity by in-
creasing the air-blast pres-
sure. This article des-
cribes a turbo-blower set
designed to meet the increas-
cr eased pressure require-
ments and gives the results
of steam consumption and
speed-regulation tests.

of the blades are supported by heavy
rings.

The bearings of both machines are
of the self-alining, ring-oiling type. As
the rotors of both turbine and blower
comprise but a single wheel in each
case, the construction can be made very
light, while maintaining ample strength
and rigidity for the speeds employed.
This factor, together with the use of
liberal bearing surfaces, eliminates the

A sliding gate valve on the end of this
cone could be opened and closed quickly
to throw the load on and off the blower
almost instantaneously, thereby testing
the governing properties of the tur-
bine and the actual behavior of the
whole machine under ser\'ice conditions.

The guarantees called for in the con-
tract stated that the turbines were to
develop 200 brake-horsepower when
operating with a steam pressure of 125
pounds at the throttle and a back pres-
sure varying from zero to 5 pounds.
The steam consumption guarantee v.as
38 pounds per brake horsepower with
atmospheric exhaust and 42 pounds per
brake horsepower with 5 pounds back
pressure. The quantity of air to be
delivered by the blower was 14,000 cutic
feet per minute against a pressure of
40 inches.

The turbines are arranged for 5
pounds back pressure in order that the
exhaust from the turbine may be dis-
charged directly to the gas machine; a
system which, although naturally im-
pairing the efficiency of the turbine to
a certain extent, shows a distinct gain
in overall efficiency over the old system

Tl KHIM.-DHIVHN HiCH-PKUSSURE GAS BLOW KR

necessity of any special forced oiling
system and its attendant complications.
Being a new design, these machines
were subjected to n series of exhaustive
tests at the makers' works, and final
acceptance tests were carried out under
conditions arproximating as nearly as
possible the gas-works practice. To ob-
tain this a special cone was constructed
and fitted to the outlet of the blower.

of utilizing live steam in the generator.
In addition to being more efficient, this
arrangement is obviously more con-
venient.

Tests, the results of which are given
in the accompanying tabic, were con-
ducted by Mr. Stiles, superintending
engineer of the Brooklyn Union Gas
Company, and Mr. Wcpfcr. of the sa'ne
company. The full log of the readings

278

taken is given, and an examination of
this will show that both the turbine and
the blower have beaten their Ruarantees
by a large margin.

The method of testing was as follows:
Pressure, temperature and calorimeter
measurements were taken just before
the governor valve and the exhaust
pressure was measured in the exhaust
pipe just beyond the outlet of the tur-
bine. The exhaust steam was taken to
a surface condenser, and the discharge
water from the hotwell was weighed.
Condenser leakage tests were made be-
fore and after the turbine tests and
they showed that the leakage was negligi-

POWER

anteed maximum. Reducing the guar-
antee conditions to steam consumption
per air horsepower, the guarantee calls
for 86.13 pounds maximum steam con-
sumption per air horsepower, whereas
the tests show 58.5, or an overall Ran-
kine cycle efficiency of 25.2 per cent.

The speed regulation tests showed a
speed variation as follows:

So blower loail. 2190 revolutions per minute.
l''iill load, thrown on momentarily. 2400 revoUi-

tion.s per minute.
I'ull load, settled. 2460 revolutions per minute.

Thus it will be seen there was a
motnentary speed drop of 3.6 per cent,
and a settled drop of only 1.2 per cent.

With the full load on the blower and

August 22, 1911

V^elocity from Heat Energy

In steam-turbine work it is necessary
to calculate the velocity which would
be acquired by the jet when the steam is
expanded so as to convert a given num-
ber of heat units into work.

This may be done by multiplying the
square root of the number of heat units
available by 223.6.

For example: A pound of steam of 210
pounds absolute superheated 85 de-
grees, expanded to atmospheric pressure,
would convert into work 205 B.t.u. and
this work done upon the pound of steam
would get it into velocity at the rate of

RESULTS OF STEAM CONSUMPTION TEST

■g

'^S

c

i

o

*^ o.

o

a.

1

1.

fa

I

£

1

1

si

01 »

8

P.

h

i

1

>

3

a

.1

II
P

if

of
1

II

o.

It

c
•5

£|

|i

ill

s

p.

pi

"3 S

>

H

>

■5 t-.

1"

IS
>

1

<

1

2-10

140

103

17

0

2,480

114

2-13

433

129

304

6.0.80

6,200

2-15

131

103

26

0

2,470

3.5

47.6

27,000

15,220

114.1

2-16

476.5

157

319.5

6,390

6,560

2-19

481

137

344

6.S80

7,000

2-20

143

105

17

0

2,480

3.6

48.95

27,350

15.400

118.6

2.22

495

159

336

6.720

6,840

2-25

I4.->

10.5

23

0

458

136

332

6,640

6,800

2.480

3.5

47.6

27.000

13,220

114.1

2-28

490

159

331

6,620

6.780

2-30

135

102

30

0

2.440

114

3.4

46.2

26,600

15.000

109.1

2-31

451.5

135

316.3

6,330

6.525

2-34

477

161

316

6,320

6.475

2-35

150

106

24

0

2,480

3.8

51.7

28.100

15,850

129

2-37

494

136

3.58

7,160

7.340

2-40

'hs

101

25

0

478 5

157

321 5

6,430

6,600

2,450

3.4

46.2

26.600

15,000

109.1

2-43

447.5

137

310 3

6.210

6,365

2-45

14S

100

22

0

2,445

3.4

46.2

26,600

15,000

109.1

2-46

468

161

307

6,140

6,280

2-49

434 . 5

135

319.5

6.390

6,520

2-50

153

102

19

0

2,450

3.4

46.2

26,600

15,000

109.1

2-52

480 . 3

160

320.5

6,410

6,530

2-55

150

101

19

0

458

134

324

6,480

6,610

2,460

113

3.4

46.2

26,600

15,000

109.1

2-58

470 . 3

161

309.5

6,190

6,310

3-00

150

too

17

0

2,460

3.4

46.2

26.600

15,000

109.1

3-01

438 3

132

306 5

6.130

6,240

Average

14.5.

102.5

22

too

0

6,442

6,587

2,463

113.6

0.0694

3.48

47.3

26,900

15,169

112.6

58.5

ble. The condenser was vented at the
top so that no vacuum was produced
at the exhaust of the turbine. The air
was measured by placing a long cone on
the discharge of the blower; the cone
was calibrated, and found to have a
coefficient of discharge of 0.94. The
pressure was taken by means of a
mercury U-tube placed directly at the
outlet of this cone. According to the
guarantees in the contract the total
steam required to deliver 14,000 cubic
feet of air per minute at 40 inches of
pressure was to be not more than 7600
pounds per hour, when the turbine was
working under atmospheric exhaust con-
ditions.

The actual air horsepower delivered
during the test was 112.6, and the dry
steam consumption was 6587 pounds
per hour, so that the blower was deliv-
ering 27.5 per cent, more work than
was called for, with a steam consump-
tion 13.35 per cent, less than the guar-

the gate suddenly closed, the following
results were obtained :

Full load. 2460 revolutions per minute.

No blower load, momentary, 2575 revolutions

per minute.
No blower load, settled, 2490 revolutions per

minute.

This shows a momentary jump of
4.7 per cent, and a settled increase of
1.22 per cent.

It has been pointed out that a big sav-
ing is anticipated in the gas-machine
end by the adoption of this new blower,
but it should be further pointed out that
the saving in economy in the blower
itself is quite a factor. In some tests on
a 22-inch blower made recently under
substantially the same conditions and
Vith the same type of blower the over-
all water rate was 76.2 per cent, per air
horsepower as against 58.5 now ob-
tained. In other words, the new blower
sets show an efficiency 16.7 better than
those now universally used in this coun-
try.

14.32x223.6=3202 feet per second, 14.32
being the square root of 205.
The reason for this is that

T= 1 2 gE
where I' =r Velocity in feet per second,
g = 32.16 " •'

E = Energy in foot-pounds.
If the energy is given in heat units U,
the mechanical energy will be
E = 777.52 U,
so that

v=] 2 X .^:^.i6 X 777-52 y U

:=22;v6.'S7 1 U

The E = — '- formula was ex-
2 <7

plained by Uncle Pegleg in Power for

Mav 17. 1010.

From all accounts alcohol has not been
a success in Germany as an industrial
fuel.

August 22, IPII

POWER

279

Steam Engines and Steam Turbines

There is so much interest shown in
the discussions of the relative merits
of the reciprocating steam engine and
the steam turbine as prime movers that
I feel that any positive information re-
lating to the performances of either may
be helpful in pointing out the merits of
each and assist in determining where
either is most likely to prove satisfactory.

In 1907 I had charge of a plant on the
Pacific coast in which there were one
9 and IS by 16-inch, two 16 and 32 by
22-inch tandem-compound condensing en-
gines and one 300-kilowatt steam tur-
bine. From the operating report for
October of that year (see table), it will
be noticed that the engines and turbine
were operated part of the time condens-
ing and part noncondensing.

By William Westerfield

A hr

cj description

of the

opera

ting conditions

under

'..liich

a comparative

test of

rccip}

ocating-engine-

and

turbine-driven tiniU

was

made

condensing an

d non-

coiide

using.

consumption per output is more uniform
in the steam turbine than in the re-
ciprocating engine under widely varying
load conditions. This may be the case
when the consumption of the prime

oi'eh.xtim; ri;

PORT FOR THE .MONTH

•:NDI-M; ncTOBER .11. l'.>l>7

Oil per

Dav of

Kilowatt-hr.

Total Oil,

Kilowatt-hr.,

.Month

Totals

Gallons

Gallons

Unit Operated

1

2.424

1,437

0.59

Turbine, condensing

2

2.434

1,282

0.53

Turbine, condensing

3

2,160

1,282

0.59

Turbine, conden.sing

4

2.496

1,375

0.55

Turbine, condensing

5

2.784

1,531

0..i4

Turbine, condensing

6

2.280

1,531

0 67

Turbine, condensing

7

2.184

1,313

0 60

Engine So. 1* noncondensing

8

2.040

1,531

0.75

F^ngine .So. 2,* noncondensing

9

2.184

1,594

0.73

Turbine, noncondensing

10

1.728

1,812

1.04

Turbine, noncondensing

11

2.184

1,468

0 67

Turbin*', noncondensing

12

2..J44

1,500

0.5.S

Engine .No. 1, condensing

13

2.040

1.562

0 76 .

Turbine, condensing

14

2.664

1,313

0 49

Engine .So. 1, condensing

15

2..i92

1,437

0 .59

Engine No. 1. condensing

16

2.784

1,531

0.55

Turbine, condensing

17

2.516

1.406

0.55

Turbine, condensing

18

2.808

1.46S

0.52

Turbine, condensing

iS

3,024

1,500

0.56

Engine No. 1. condensing

JO

2,256

1,.500

0.66

Engine No. 1. condensing

21

2,592

1,375

0 53

Engine No. 1, condensing

22

2,976

1.594

0.53

Engine .No. 1. condensing

23

2,712

1,594

0.58

Engine .No. 1. condensing

24

2,832

1,531

0.54

Engine No. 1. condensing

2.5

3.048

1,531

0 50

Turbine, condensing

26

3.048

1,812

0.59

Turbine condensing

27

2.208

1,375

0.62

Turbine, condensing

28

2.640

1,281

0 44

Turbine, condensing

29

2,616

1,468

0.56

Turbine, condensing

30

2,544

1,250

0.45

Turbine, condensing

31

2,688

1,312

0.42

Turbine, condeiLsing

Total

78,020

.\veraRe. . . .

0.55

•Engines .Nos. 1 and 2 wen" 10 and .'i.' by 2J-inch tandem compound.

Conditions then were not favorable for
making an efficiency test but were good
for making a comparative test. It will
be noticed that in running condensing
from the first to the sixth, inclusive, the
turbine required from 0.53 to 0.67 gal-
lon of fuel oil per kilowatt-hour output.
On the seventh and eighth the engine
used 0.60 and 0.75 gallon running non-
condensing, while on the ninth, tenth and
eleventh, the turbine, running under the
same conditions, used 0.73, 1.04 and f).67
gallons. On the thirieenih, the turbine
running condensing required 0.76 gallon
per kilowatt-hour while 0.66 gallon is
the highest consumption shown by the
engine. In running noncondensing the
turbine required 1.04 gallons against 0.75
gallon as the highest required by the
engine. The reverse of this performance
may usually be expected; that is, the

mover alone is considered, but under
the conditions in this plant the report
covers the entire work, including all the
auxiliaries.

Up to the twelfth with the steam tur-
bine a vacuum of from 26 to 28 inches
was maintained, which was not as favor-
able as is generally advocated. After
this a new circulating pump was in ac-
tion, and it will be noted that the re-
sults are better after this date, as a
vacuum of from 27 to 28' ^ inches was
maintained. The larger engines and the
turbine were of approximately the same
horsepower rating. The engines ex-
hausted into condensers having 600
square feet of cooling surface each and
the turbine into one having 1200. With
the engine condensers there was used
a combined air and circulating pump,
while with the turbine condenser there

were a centrifugal circulating pump, a
motor-driven turbine hotwell pump and
a dry-vacuum pump, the arrangement
being substantially as shown in Fig. 1.

The engines did better than the tur-
bine on the light loads as the work of
the condensing apparatus could be varied
as the load varied, it being only neces-
sary to vary the speed of the combined
pump so that it would maintain a suit-
able vacuum. In the case of the tur-
bine condensing apparatus this w-as not
possible because the centrifugal pump,
like the turbine, is a one-speed machine,
and its speed cannot be so readily varied
as may the ordinary air and circulating
pump, so that when the turbine was run-
ning on the light load the condensing
apparatus was doing almost the same
work as on the peak load.

The lowest consumption of fuel for
the engine-driven units for the month
was 0.49 gallon per kilowatt-hour with
a vacuum of 22 inches on the peak load,
and as the load became lighter the vac-
uum would increase to 26 inches. The
lowest fuel consumption with the tur-
bine was 0.42 gallon on the thirty-first.
The fuel cost was 2 17 cents per gallon,
or 0.88 cent per kilowatt-hour output.
For the month the average fuel consump-
tion was 0.55 gallon per kilowatt-hour;
the cost per kilowatt-hour was 1.16 cents;
the total cost per kilowatt-hour output,
not including interest and depreciation,
was 1 7 10 cents.

There were several drawbacks which
made great economy impossible while
I was in this plant, though they were
remedied later on my recommendation.
The pumps delivered water to the boil-
ers through a closed feed-water heater
which instead of being set below the hot-
well was above it and had to lift the
water with the result that when the load
became heavy and the water of condensa-
tion quite hot. cold water make\ip or
waste was used to keep the temperature
down.

Although I did not get the results I
desired, I did succeed in reducing the
cost per kilowatt from 3 cents per kilo-
watt-hour in July to 1 7/10 cents in
October of the same year, and acquired
a knowledge of many things I could not
have learned in any other way, among
them being that the steam turbine in
which the flow of steam is horizontal will
not stand water in any quantity. When
I went to this plant the turbine had not
been started, but was hooked up ready
for steam. There was a 9 and 18 by 16-
inch compound engine set near the tur-
bine, and rather than run a new line
the ell where the line dropped to the
engine was taken off and a tee placed
in its stead: from the top of this tee
another ell gave an outlet to the turbine.
There were separators in the steam pipes

280

POWER

August 22, 1911

to tlie engine and turbine, wliich were
bled by liand, but no traps.

The piping system was poorly de-
signed. From the header a 14-inch steam
pipe led into the engine room, Fig. 2,
and as the largest steam pipe to the en-
gines was 8 inches, there was a depth
of 3 inches in the large pipe below the

Loss Due to Incomplete
Combustion

The accompanying tables show in per-
centage and dollars the loss that oc-
curs from incomplete combustion, which
results in a low CO.- percentage on every
-■^lOOO worth of coal burned. Table 1

T.\BLE 1. LO.S.S DCE TO INCCMPLETE

CO.MBUSTIO.V H.WI.NG A LOW CO,

ON EVERY $1000 WORTH OF

CO.\L BLRNED

Percentage CO,

Loss, Per Cent.

Loss, Dollars

U

No Loss

1.3

H

15

12

2i

25

11

■ii

45

!0

6

60

9

8J

85

8

11

110

1.5

150

6

19i

195

5

26i

265

4

32

320

3

53 i

^t'io

per pound of coal and of 18 pounds of
air supplied per pound of coal consumed.
The range in stack temperature is from

T.\BLE 2. LO.SS OF HIGH TEMPER.\TURE

IN ST,\CK ON EVERY SIOOO WORTH

OF CO,\L BURNED

Arrangement of Auxiliaries

lowest point of opening in the largest
of the engine steam-pipe outlets. There
were no drains from this large pipe,
which had the habit of collecting water,
and about the time things were going
nicely on the peak load and the turbine
had all it could handle, over would come
a slug and the machine would slow down.
The only thing to do to get out of the
tangle was to get one of the engines in
on the load as soon as possible. After
a few experiences of this kind I re-
fused to operate the turbine until the
proper piping connections were made.

The actual steam consumption of the
prime mover per output may be very
misleading, but it is the best index of
the economy of the prime mover and that
of its auxiliaries, the condensing appa-
ratus and other appliances which are in-
cident to its operation. It requires a
greater amount of mechanical energy to
maintain a vacuum of 28 to 29 inches
than for 25 or 26 inches, and while the
reciprocating engine will give its maxi-
mum economy with a vacuum of 25 or
26 inches, the turbine requires 28 to 29
inches.

There are at present about 173 miles
of hydraulic power mains laid in Lon-
don served by five central pumping sta-
tions from two to three miles apart.
The supply is over 21,00,000 gallons per
week, with 6787 machines and 221 fire
hydrants connected. The number of
machines in 1900 was 4137. The latest
station is situated in Grosvenor road,
Westminister, and has five engines, capa-
ble of pumping 28,000 gallons per hour
eaoJ: into the main at a pressure of 800
pounds per square inch.

shows tlie percentage of CO2 ranging
from 14 down to 3 per cent, and showing
a loss of from 0 to 53'.. per cent, and
from no dollars to .S535. This is based
on 14 per cent. C0= as being the maxi-
mum under working conditions, and
means that with 3 per cent. CO:; there
is a loss of 53; J per cent, of the heat
units in the coal and S535 loss out of
every $1000 expended in fuel.

Loss on

Ev..Ty

Stack

Per Cent.

SIOOO

Temp..

of Heat

Wortli of

Deg.

3oing Up

Coal

Fahr.

Stack

Burned

200

4.34

S43 . 40

Temp, outside

250

5.89

58 90

air. 60 degrees.

300

7.44

74.40

350

8.99

89.90

One pound coal

400

10.54

105.40

= 14,500 B.t.u.

450

12.09

120.90

500

13.64

136.40

18 pounds of air

560

15.50

155 00

per pound of coal.

200 to 560 degrees Fahrenheit; the per-
centage of heat loss going up the" stack
ranges from 4.34 to 15.5 per cent, and
there is a loss in dollars of from S43.40
to SI 55.

Both tables are worth noting and the

FiG. 2. Turbine Pipe Arrance.ment

In Taole 2 is shown the loss from a
high stack temperature for every SIOOO
worth of coal burned. This table is based
on an atmospheric temperature of 60
degrees, the coal containing 14,500 B.t.u.

wise engineer can get considerable food
for thought in comparing them with the
lesults obtained from his own plant.
These figures were prepared by George
H. Diman, consulting engineer.

August 22, 1911

P O W E R

281

Advantages of Superheated Steam

Thermodynamics teaches that little
gain in work can be obtained by the use
of superheated steam, yet experience
shows that moderate superheat gives a
decided advantage. The increase in work
theoretically possible can best be shown
by the temperature-entropy diagram. Re-
ferring to Fig, 1, the theoretical amount
of work between the limits expressed
in the diagram can be represented by
the area A B C D E F A. The increase
in the available work by the use of
superheated steam over that which can
be obtained with saturated steam is
shown by the area C D E F C. Thus,

Area ABCFA 264 B.t.u.

Area A BCDEFA 282 B.t.u.

Area e£»£fC-2S2 — 264= IS B.t.u.
or 6 s per cent. gain.

It is clear that if the only advantage
in the use of superheated steam were
this 6.8 per cent, gain, it would not pay
to go to such pains and expense to use
it. Fortunately, however, superheated
steam will reduce cylinder condensation.

Consider a simple steam engine work-
ing between the temperature limits of
338 and 212 degrees Fahrenheit. At
release and during exhaust the cylinder
head, clearance space and that part of
the barrel exposed to the steam will be
cooled by the relatively cool exhaust
steam. This cooling will vary with the
clearance spaces, ratio of expansion, etc.,
but when the hotter admission steam en-

338 Degrees Fahrenheit

B}' H. J. Macintire

100 lb. Steam Pressure

ik Degrees Fahrenheit

PtowEK

Fig. 1. Gain Due to Superheated

Steam as Shown by the Tem-

per.'.ture-Entropy Chart

ters it encounters this cooler metal and
condensation takes place. As the steam
condenses, more steam from the boiler
comes in to take its place; hence at
cutoff there is much more water and
steam than is accounted for as steam by
the indicator diagram.

Referring to Fie. 2. the area M N Q R
represents an ideal diagram using the
theoretical amount of steam, but cyl-
inder condensation increases the amount
of steam entering the cylinder, and the
actual amount of steam is represented

The effect of superheated
steam on cylinder conden-
sation; some results gained
by the use of superheated
steam and its limitations.

by the line M O. The actual indicator
diagram is shown cross-hatched, and the
ratio of its area to the area MO PR is
the engine's efficiency as compared with
the Rankine cycle. Therefore, it is ap-
parent that if cylinder condensation can
be eliminated the efficiency will be great-
ly increased. Superheated steam will do
this to a large extent.

It has been shown by a number of
experiments that the best exchange be-
tween the steam and the walls of the
steam engine is much greater when the
walls are wet than when dry. It is de-
sirable then to keep the steam dry until
cutoff at least, or, better still, until re-
lease. To do this the steam must be
superheated enough to raise the tem-
perature of the walls, clearance spaces,
etc., to that corresponding to the satura-
tion temperature of the incoming steam.
The superheat should not be carried high
enough, however, to have superheated
steam after release as that would repre-
sent a loss in economy.

The question is often heard: "If the
gain by the use of superheated steam
is so great, why has it not been used
more?" The reasons are as follows:

1. There is a rapid deterioration of
the superheater due to the oxidation of
the tubes.

2. With saturated steam the water
due to cylinder condensation acts as a
lubricant, and the temperature of the
steam is not great enough to disintegrate
good grades of cylinder oil. With super-
heated steam, however, there is no cyl-
inder condensation, except near release,
and the temperature of the steam Is so
great that oil which lubricates satisfac-
torily with saturated steam is of no
value at the high temperatures, and only
recently has a special oil been manu-
factured that is of use at high degrees
of superheat.

3. A valve that is steam fight at room
temperature will warp badly at 400 or
.VX) degrees Fahrenheit, This can be
overcome by rccrinding the valve to its
seat after having run it exposed to the
superheated steam.

These are the principal troubles, hut
there are a number of lesser ones, in-
cluding the need of special piping and

fittings and special packing, greater
trouble with expansion of the pipe lines,
etc. These obstacles have been over-
come in various ways and superheated
steam is now being permanently adopted,
especially in turbine work. Following
are the results of a test where super-
heated steam was used to advantage.
The engine was of 20 horsepower, sim-
ple noncondensing and took steam at
100 pounds gage:

steam per

Increase in Indicated

Supertieat, Thermal Efficiency. Horsepower.

Degrees Per Cent. Pounds

0 0.0 39.2

98 12.0 33 4

254 51.4 23 1

321 70.8 19 8

Fig, 2, Actual and Apparent Condi-
tions IN Cylinder

In this test it was found that a super-
heat of 270 degrees was necessary in
order to obtain superheated steam at
cutoff, and 325 degrees of superheat to
have dry steam at release. The tem-
perature of the walls did not exceed 400
degrees Fahrenheit with the steam en-
tering the cylinder at from 615 to 650
degrees, yet as the walls were dry there
was no great heat exchange.

In conclusion, it may be said that the
general effect of superheated steam is
to give almost constant efficiency both
at full and at small loads, and to give
the simple engine an economy nearly
equal to that of the higher grades of
compound engines.

A recent Aiistr-iiian invention to over-
come troubles of corrosion and pitting
in metals, especially boilers, due to elec-
tric chemical action of ingredients in
water with which they are brought in
contact, appears to have met with suc-
cess in Sydney. The plan of the inven-
tion, according to The Encinccr. is to
introduce, by dynamos, weak electrical
currents on to the metals intended to be
protected, thus neutralizing the galvanic
action of the corrosive substances con-
tained in the water. The invention is
expected to make an immense saving by
eliminating the necessity for using zinc
in various forms, boiler fluids, etc., to
combat corrosive tendencies, and also in
dispensing with rctubings and other re-
pairs. The process has been tried with
success at Melbourne University.

282

POWER

August 22, 1911

Sampling and Analysis of Furnace Gas

The furnace conditions prevailing both
in small plants and in large industrial
establishments in this country are fre-
quently far from satisfactory. If such
conditions are to be improved, they must
be more thoroughly understood, and
means must be found to insure complete
combustion of the fuel and yet to per-
mit operation with such an excess of air
as will result in the greatest efficiency.

In this work the services of the chem-
ist are indispensable. A very important
problem is the determination of the small

Fig. 1. Glass Vessel for Holding
Sample

percentage of unburned combustible mat-
ter that escapes from the furnace in the
flue gases. Under ordinary circum-
stances so little as 0.1 per cent, of un-
burned combustible matter in a furnace
gas is equivalent to about 1 per cent, of
the fuel used; and for the determination
of such small percentages of gas more
accurate and refined methods are re-

By J. C. W. Fraser

and E. J. Hoffman

Apparatus for collecting
instantaneous samples and
for collecting samples cover-
ing a period of time. Des-
cription of a measuring
burette leith which readings
ma:' be made ivith a great
degree of accuracy.

♦.Vlistr.ii't <'l" a ImHetin published bv tl].-
I'.nreau of .Mini's. Washington, E). C.

quired than have ordinarily been avail-
able heretofore.

Sampling of Furnace Gases

The proper sampling of gases is fre-
quently difficult when the gas mixture
under investigation is not homogeneous
?nd in sampling furnace gases the prob-
lem is further complicated by the neces-
sity of protecting the part of the sam-
pling apparatus introduced into the
heated gases. It is not difficult to obtain
a sample of gas from a given point
within a furnace; but as in most cases
the composition of the gas is constantly
changing, some method must be pro-
vided by which the sample will represent
the average composition of the gas at
the point of collection during a desired
period: or the sample must be collected
almost instantaneously, so that it will
merely represent the composition of the
gas at the point and at the instant of col-
lection.

A sample taken in either of these ways
is only representative of the gas occupy-
ing a certain space surrounding the point
of collection. In order to determine the
average composition of the entire volume
of gas it is necessary to multiply the
number of samples and to distribute the
points of collection in such a manner
that the average of the samples will cor-
rectly represent the entire gas body. The
number of samples taken should depend
on the differences in composition that are
presumed to exist throughout the volume
of gas to be sampled. The difference in
composition between samples taken at
any two adjacent points of collection
should not be greater than from 0.3 to 0.5
per cent.

Continuous Sa.mplinc

The sampling of flue gases can usually
be accomplished satisfactorily by using
a perforated iron pipe placed in the flue
at the desired point.

A common method of collecting a sam-
ple is to attach a large bottle filled with
water to the outside open end of such
a sampling tube and then to allow the
water to escape at such a rate that the
gas, which replaces the water in the bot-
tle, is collected in the desired time. It
is not advisable to sample gases that con-
tain a considerable proportion of carbon
dioxide in this way because of the great
ease with which water, or even a solu-
tion of common salt, dissolves that con-
stituent and thus tends to equalize the
content of carbon dioxide in the samples
collected.

The following method was devised to
obviate this difficulty as well as certain
others.

Collection and Storage of the
Sample

The glass vessel illustrated in Fig. 1- is
utilized both as an important part of the
sampling device and as a holder for the
sample after collection. The vessel
should have a capacity of 150 to 250
cubic centimeters. If, when the vessel is
in the position shown and is filled with
m.ercury, the stopcocks a and b are
opened the mercury will flow from the
lower tube. The gas will then be drawn
through the upper tube, enter the vessel
at c and collect above the mercury. So
long as the surface of the mercury re-
mains above c the same volume of gas
will be collected in each equal interval
of the sampling period, and the sample
obtained will be representative. The
time required for a certain amount of
mercury to run from the vessel can be
varied from that taken when both a and h
are completely open to a period of from
8 to 10 hours, or even longer, by attach-
ing at d, by means of a rubber rube, a
short piece of glass tubing drawn out to
a smaller diameter. By trial these short
glass tubes can be made of proper diame-
ter to deliver the mercury at almost any
desired rate.

.■\fter the sample has been collected,
the tube above a is tilled with mercury
from a small funnel whose stem has been
drawn out to a capillary. The vessel is
then inverted and, by means of a rubber
tube attached to a mercury reser\'oir, the
inclosed gas is put under a pressure of
about 100 millimeters of mercury. When
the vessel is returned to its original posi-
tion, as shown in the illustration, the
stopcocks a and b are mercury sealed
and there is no danger of gas leaking
into or out of the vessel.

When removing the sample for analysis
the vessel is again inverted and the tube
above b is filled with mercury and
attached to the burette. By means of the
mercury reservoir previously used to put
the gas under pressure, the desired vol-

August 22. 1911

P O ^X' E R

283

ume of gas is forced out of the vessel
into the burette. If the gas is to be
measured over water, the tube above the
stopcock b is filled with water instead of
mercury.

In order to facilitate the safe handling
of these vessels it is necessary to mount
them in a portable stand, and frequently
they are arranged in batteries of two to

Fic. 2. Rack for Mounting Sampling
Tubes

four each. Fig. 2 illustrates a convenient
method of mounting four of these tubes.

Water-cooled Sa.mplinc Tube
The portion of the sampling apparatus
which is introduced into the furnace may
be either a water-cooled metal tube or,
better, a water-cooled quartz tube.

Fig. 3. Watfr-cooled Sampling Tube

A satisfactory type of water-cooled
metal tube is illustrated by A in Fig. 3.
The inside tube, through which the gas
is collected, is kept cool by cold water,
which passes through the surrounding
tube and returns through the outside

annular space. When the inner tube
is of quartz, the only difference in con-
struction is the use of asbestos packing
to insure a water-tight joint at each end.
An apparatus provided with a quartz tube
is more fragile than one w^holly of metal,
but it is preferable as it has a greater
range of utility and may even be used in
the fuel bed. This tube is connected
directly with the mercury-filled sample
receiver, and the sample is taken from
the current of gas flowing through the
lead tube.

To be sure that the current of gas is
flowing properly through the tubes it is
necessary to introduce a trap at some
point beyond that at which the sample is
taken from the lead pipe. The trap is
simply a wash bottle containing water
through which the gas bubbles on its
way to the aspirator, the rate of bubbling
roughly indicating conditions in the tubes.
Fig. 3 illustrates the entire sampling
system.

Instantaneous Sampling
Frequently it is desirable to know the
composition of gases at some point in a
furnace at a certain definite instant, par-
ticularly when there might be reason to
suspect that the gases would decompose
during a period of continuous sampling
or when studying the progress of reac-
tions in the furnace. This method is em-
ployed by certain investigators in collect-
ing samples from the flame of burning
gases and from the explosion flame of
coal dust, etc. The use of this method
also enables one to obtain certain infor-
mation concerning furnace conditions
which he might not be able to obtain by
the use of the continuous-sampling
method. It was for the purpose of col-
lecting instantaneous samples that the
device shown in Fig. 4 was constructed.

Description of Apparatus
The apparatus consists of a quartz sam-
pling tube of 100 cubic centimeters
capacity, immersed in water contained in
the steel tube B. which is 1.2 meters In
length and 10 centimeters in diameter. At
each end the vessel terminates in a thick-
walled quartz tube. I -millimeter bore, pro-
vided with a stopcock as shown. One of
the tubes h extends 150 millimeters
beyond the stopcock and the open end
projects beyond the end of B. An enlarge-
ment <iO millimeters from the stop-
cock gives a firmer hold for the cement
of litharge and glycerin with which the
cavity in the collar c is filled; in this way
c is fastened permanently to h. The
brass device for opening and closing the
sampling tube from the outside is sup-
ported by the two end pieces r of the
steel tube li. It consists of the brass
frame C, in which is supported the
mechanism for turning the stopcock. This
includes the br.iss shaft h, on which is
set the wheel ( and, beneath the frame,
the brass plate /. carrying four projec-
tions, g. which fit around the handle of

the stopcock. To avoid straining the
stopcock in turning, which might occur if
h were not centered above the stopcock,
the pieces g are small rollers. The face
of the wheel / is threaded to engage with
the threaded end of the brass rod r. The
piece k serves as a guide for the brass
rod and affords a means of adjusting the
threaded end of the rod to the face of i.
The adjustment is accomplished by hav-

F'c. 4. Dfvicf for Collecting Instan-
taneous Samples

ing the hole in k through which the rod r
passes eccentric to the bearing of k in C.
A movable stop, m, can be set to limit
the rotation of i and the extent to which
the stopcock may be turned.

Operation of Apparatus

Before collecting a sample the end
piece r, which is to carry the vessel

284

POWER

August 22, 1911

is removed; then the quartz tube is
placed in position and the nut tight-
ened. During this operation c is pre-
vented from rotating by two small dowel
pins which enter holes provided for them
in c. By trial, m is adjusted so that when
the rod r reaches it the handle of the
stopcock is rotated 90 degrees. It is cus-
tomary to adjust the stopcock so that com-
munication with the vessel is established
when r is against m; the withdrawal of r
then closes the stopcock. Having the
stopcock properly adjusted, the end piece
e is bolted to B, and the latter is vertically
suspended by a handle clamped on the
other end. While in a vertical position
the rod r is introduced through the brass
bushing at the upper end and finds its
way without difficulty into the hole in k.
The steel tube B is filled with water
through n, which is then closed by a
perforated rubber stopper, through which
passes a short glass tube bent at a right
angle, its projecting end being directed
upward *hen the apparatus is in use.
This tube relieves the internal pressure
when the temperature of the water rises.
The apparatus is then taken to a vac-
uum pump and placed in a horizontal posi-
tion in two semicircular rests which pre-
vent its moving while it is connected with
the pump. When the tube A is ex-
hausted, and while it is still connected
with the pump, r is withdrawn so far
that the threaded end leaves / but re-
mains in k, thus closing the stopcock. The
time at which r and / become disengaged
can be readily determined by the in-
creased ease with which r moves. The
pump is disconnected, and as soon as
convenient the apparatus is introduced
into the furnace, the open end of the
tube h being placed at the point from
which the sample is desired. The stop-
cock is opened by pushing in the rod r
until it is in contact with m, and after
the short time required for the vessel to
till the rod is withdrawn and the stopcock
thus closed.

.^s the sampler remains in the furnace
only about 30 seconds and as the quan-
tity of water in B is considerable, it is
unnecessary to provide for a circulation
of this water. In collecting a sample it
was found that the temperature of water
in B did not rise inore than 10 degrees,
even when the tube was inserted in tht
hottest part of the furnace.

After removing the apparatus from the
furnace, the water is drained from B,
the rod r is withdrawn, the nut d is
started to insure its subsequent easy re-
moval, and the end piece c. carrying b.
is removed. Then d is taken entirely off.
and after the two glass tubes have been
filled up to the stopcocks with mercury
the sample is transferred to one of
the holders illustrated in Fig. 1. Since
it requires about 30 minutes for the com-
plete operation of collecting a saiuple
in this way, a series of samples is gen-

erally collected and stored in the holders
before making the analyses.

Detkrmination of Moisture and Nitric
Oxide

With the apparatus illustrated in Fig.
4 the amount of water vapor accompany-
ing a gas sample can be easily known by
absorbing the moisture and weighing it.
Likewise, the presence of traces of nitric
oxide in furnace gases has been shown
by using a simple modification of the
method just described. The determina-

FiG. 5. Sampling Tube Containing
Compensating Device

lion of nitric oxide is accomplished as
follows:

The sampling tube used is a water-
cooled quartz tube similar to the one
illustrated in Fig. 3. An evacuated 8-liter
bottle is used as a receiver for the gas
sample in place of the quartz vessel in
Fig. 4. Two glass tubes, each provided
with a carefully ground stopcock, pass
through two holes in a rubber stopper
which closes the bottle. One of these
tubes extends aliuost to the bottom of the
bottle; the other, which ends just below

the stopper, is bent at a right angle and
connected directly with the water-cooled
quartz tube.

After the collection of the sample, an
excess of an alkaline solution of potas-
sium permanganate is introduced into the
bottle and allowed to stand for 24 hours,
when the solution is withdraw-n and the
free ammonia distilled off. Potassium
hydroxide and fine aluminum powder are
then added and the mixture allowed to
stand several hours, "after which the am-
monia formed is distilled into standard
sulphuric acid.

The presence of nitric oxide can be
demonstrated qualitatively by introduc-
ing a solution of starch and potassium
iodide into the bottle directly after the
collection of the sample. The blue color
does not appear immediately, probably
owing to the presence of sulphur dioxide
in the gas. but in a short time the color
becomes quite pronounced.

In the gases examined the quantity of
the nitric oxide found varied from 0.015
to 0.031 per cent. At the time of taking
these samples the furnace conditions
were not favorable to the formation of
this constituent, and it is believed that
the percentage of nitric oxide in the fur-
nace gases is frequently much greater.

Analysis of the Sample

The sample having been collected, its
analysis is made most conveniently by
the method of Hempel. The use of
mercury in the burette is to be preferred
to that of water; but whichever is used,
the burette should always be provided
with a water jacket to avoid errors due
to sudden changes in temperature. While
the ordinary Hempel burette is sufficiently
accurate for most purposes, it does not
enable the observer either to detect or
to determine changes in volume amount-
ing to 0.1 cubic centimeter or less, since
the error in reading the burette itself
cannot be less than this volume.

It is of some importance to be able
to measure smaller percentages of com-
bustible gases than can be determindl
by the ordinary Hempel method, since ths
flue gases are so diluted that a small per-
centage of combustible matter in them
corresponds to a much greater percentage
of the fuel. To find these small percen-
tages, a very accurate method is required.
The apparatus described by Hempel for
exact gas analysis, which provides a tube
for compensating errors due to variations
in the pressure and temperature of the
atmosphere (the principle of Pettersson),
is in certain respects unsatisfactory. In
this instrument a considerable portion of
the air in the compensator and an ap-
proximately equal volume of the gas
being measured are not inclosed in the
water jacket, and while there is a tend-
ency to equalize any error due to this
arrangement, the compensation is perfect
onlv when the total volumes of the two

August 22, 1911

P O \i' E R

285

gases are equal. Further, the burette it-
self cannot be read with sufficient accu-
racy.

In 1900 A. H. White published a de-
scription of an apparatus devised tp
obviate these difficulties, in which the
principle of automatic compensation for
changes in temperature and pressure as
suggested by Pettersson and modified by
Hempe! and others is utilized in an im-
proved form. Its measuring portion con-
sists of two limbs, suggested by the
burette of Otto Bleier, one a series of
bulbs to contain the larger portion of the
measured gas, the other a long straight
tube of small capacity on whose scale
all final readings of volume are made.

To obviate the same difficulties and to
measure all possible changes in volume
the apparatus described below was de-
signed by the writers.

Description of Apparatus
The apparatus, illustrated in Fig. 5,
consists of the burette A and the auto-
matic compensating device B. The
measuring portion of the burette A and
the whole of the compensator B are in-
closed in the water jacket C. The meas-
uring portion of the burette consists of
the two limbs a and b, the graduated
portions of which are 66 centimeters
long and united at the top in an inverted
Y-shaped connection to which a Greiner-
Friedrich two-way stopcock is attached.
Through ,this stopcock communication
can be made with either of two short,
thick-walled tubes of small bore, one of
which is connected with the compensa-
ting device. Outside the water jacket C,
at the lower end, is a second Y tube,
each limb being provided with a stop-
cock and attached by rubber connections
to the projecting ends of the limbs a and
b. To the lower end of the Y tube is
attached heavy rubber tubing connected
with a mercury reservoir.

The tube a consists of a series of 10
bulbs, each having a capacity of 10
cubic centimeters between the two grad-
uation marks immediately above and be-
low it. The straight glass tube b has an
internal diameter of about 4.5 milli-
meters, and its graduated part has a total
capacity of 10.1 cubic centimeters. The
beginning of the graduated portion of
each limb of the burette is at c. The
compensator B, while utilizing Petters-
son's principle of counterbalancing the
pressure of the gas to be measured
with that of a constant mass of air occu-
pying a constant volume, is arranged in
a somewhat difTerent form from his de-
vice. The confined air, whose pressure
at a constant volume is equalized by
that of the gas to be measured, is con-
tained in the bulb d and above the
mercury surface e in the tube g. which
forms the lower termination of the bulb.
The glass tube / is connected at its
upper end with one of the communica-
tions through the stopcock of the burette

and is sealed into the top of the bulb d.
Its other end extends nearly to Ithe
bottom of g and opens beneath the sur-
face of the mercury. The diameters of
the tubes / and g are proportioned so
that the distance from the inside of g
and the outside of / is as nearly as pos-
sible equal to the internal diameter of /.
The compensator may be filled so that
the readings on the burutte are the
correct volumes of the gas at 0 degrees
Centigrade and 760 millimeters pressure,
or it may be closed under known condi-
tions of temperature and pressure and
the readings corrected to standard condi-
tions. The latter method is sufficient
for most purposes, and when it is used
the compensator may be closed by re-
placing the seal at m by a small tube
and stopcock.

Operation of Apparatus

By drawing nearly all the gas into
the limb a and adjusting the pressure
to approximately that of the atmosphere,
the number of bulbs the gas will fill
completely when at the pressure of the
air in the compensator may be ascer-
tained. Having determined this, the
mercury in the burette is brought exactly
to the level of the graduation beneath
the last bulb completely filled in the
trial experiment and the stopcock at the
bottom of the limb is closed. The re-
maining fraction of a bulb full of gas
is then made to enter the limb b, and
the two-way cock is turned so as to
place the burette in communication with
the compensator. The pressure of the
gas in the burette is then adjusted, by
means of the mercury reservoir, until
the two surfaces of mercury in the com-
pensator are on the same level. The
pressure of the gas in the burette is
then equal to that of the gas in the com-
pensator. The stopcock at the bottom
of b is then closed and the reading of
the burette taken. To this reading is
added the predetermined capacity K of
that part of the apparatus between the
graduated portion of each limb of the
burette and the mercury meniscus in the
tube /. As each constituent of the gas is
made known by the difference in the
burette readings, before and after an
absorption, this constant capacity K does
not enter into the determination of the
amount absorbed. But it is necessary to
apply this correction to obtain the initial
volume of the gas unless exactly suffi-
cient nitrogen to fill this part of the
apparatus is taken into the burette previ-
ous to the introduction of the sample.

The reading of the burette requires
some practice to secure the best results,
but with experience it can be accom-
plished quite readily and with extreme
accuracy. The gases are measured in
the moist condition, and the quantity of
water introduced into the burette and
compensator to effect this must be only

sufficient to moisten the walls of the
glass tubes. If there is enough water
in the compensator to drain down upon
the mercury, the accurate adjustment of
the mercury surfaces is rendered diffi-
cult; while too much water in the burette
is likely to stop up the narrow tubes con-
necting the bulbs and in this way to
interfere seriously with the distribution
of pressure on the gas in the burette and
consequently with the equalization of the
pressures in the burette and compensa-
tor.

With this apparatus a complete analy-
sis of gas may be made in the usual way
by connecting the burette in turn with
various absorption pipettes.

Decree of Accuracy Attainable

The limb b of the burette on which
the readings are made is graduated in
hundredths of 1 cubic centimeter, and
tenths of these divisions can be estimated
quite accurately. Experiments have
shown that 50 to 100 cubic centimeters
of gas can be measured accurately to
0.01 cubic centimeter. With volumes
less than 50 cubic centimeters the read-
ings can be more precise as a more
accurate adjustment of the mercury sur-
faces in the compensator is possible.

Water Resources of Minnesota

The cooperative agreement between
the United States Geological Survey and
the Minnesota State Drainage Commis-
sion for the purpose of investigating the
water resources of Minnesota has re-
cently been renewed, and in consequence
of an appropriation of S30.000 made by
the legislature for two years' work, the
investigations are being extended info
portions of the State not previously
touched.

The general plateau level of the north-
eastern portion of Minnesota, the section
which lies north of Lake Superior and
is contained chiefly in Lake and Cook
counties, is more than 600 feet above
Lake Superior. Numerous streams drain
this region into the lake, and although
they are small the fact that they descend
600 feet within a few miles of the lake
makes them important as sources of
water power. Many of the streams pass
through cafions having vertical walls
which would make excellent dam sites.
The investigation has been started
by making a survey of Pigeon (which
forms the extreme eastern boundary be-
tween Minnesota and Ontario), Brule
and Dcvillrack rivers. Other streams to
be surveyed arc Cascade, Poplar. Tem-
perance. Cross, Manitou, Baptism.
Beaver and Gooseberry rivers. Besides
the streams in the northeastern portion
of the State. Vermilion, Big Fork and
Little Fork rivers arc being surveyed.

Moasiircmenls of the (low of the rivers
arc also being made, to determine more
fully their value for water power.

286

POWER

August 22, 1911

A Magnetomechanical Am-
meter

A highly ingenious current-measuring
instrument, based on the law of magnetic
traction, has been brought out by an
English firm. It consists of an incom-
plete "loop" built up of laminated iron,
which forms a horseshoe electromagnet
when in use, and a laminated armature
A pivoted at P in a pair of jaws formed
in the handle M to which the loop is at-
tached.

When using the instrument, the loop
is applied to the conductor carrying the
current to be measured and the arma-
ture A closed against the ends of the
loop, the screw B being backed off away
from the spring S. The current in the
wire magnetizes the closed circuit of
laminated iron formed by the loop, and
the armature A, and the force with which
armature is held against the ends of the
U is proportional to the square of the
magnetic flux. The cross-section of the

An Ammeter Operated by Magnetic
Traction

iron in the loop and armature is such
that the flux is proportional to the cur-
rent in the conductor, within the range
of the instrument; therefore, the mag-
netic pull on the armature is propor-
tional to the square of the current in
the conductor. The magnetic pull is
measured by turning the screw B until
the spring S is flexed enough to throw
the armature away from the magnet
poles formed by the ends of the loop.
When this occurs, the pointer C, which
is attached to the thumbscrew B, will
indicate on the dial D the current flowing
in the conductor embraced by the loop.
The practical advantages of the instru-
ment are many; among them are the
facts that it can be applied to any live
conductor within its range without in-
terrupting the circuit or adding resist-
ance to it, and it is small, substantial and

easily carried in one's pocket. Presum-
ably, the degree of accuracy is not as
high as that of an ammeter of the gal-
vanometer type, but it may easily be
made to give readings sufficiently ac-
curate for the purposes of circuit in-
spection, trouble location, etc.

Central Station Service
vs. Isolated Plant Operation

By Henry D. Jackson
During the past few years we have
heard a great deal as to how much
cheaper it is to purchase power from a
central station than it is to generate it
in an isolated plant. The central station
advocates claim a great many advan-
tages, among them being a reduction in
the plant cost, thereby greatly reducing
the fixed charges on the plant; a re-
duction in the insurance on the plant,
owing to the absence of. high-pressure
steam; reduction in labor, both manual
and executive; the value of the space
left available by taking out the factory
plant, and the space formerly occupied
by belts and belt boxes; reduction in
the loss of productive capacity, . owing
to the complete avoidance of power fail-
ure, and the entire elimination of auxil-
iary service. There are still other fac-
tors which they take into account and
which I will consider later. Practically
all but one of the claims just cited is
open to argument, the exception being
the space left available by cutting out
the factory plant, and this is by no
means an entire gain in many eases, as
much of the space vacated by the iso-
lated plant is frequently occupied by the
switches, transformers and meters for
the power supply.

In considering the reduction in the
plant cost, this factor naturally enters
into the cost of power as produced in
an isolated plant; but the central sta-
tion agents are not satisfied to take into
account only the factors which should
enter into the plant cost; they desire to
tack on an additional figure which is
frequently as large as, or larger than.

all the rest of the fixed charges put to-
gether, this being the item mentioned
as profit ratio. It is frequently a fact
that the reports, as shown to a pros-
pective purchaser by the central-station
sales agent, would not be sufficiently
strong to warrant the purchaser in
adopting central-station service unless
this profit ratio were taken into account.

The power plant is quite as necessary
a part of the manufacturing business as
is the building in which the work is
carried on. When a manufacturer goes
into business, he has the choice between
erecting a building for himself, or rent-
ing one. If in his opinion he can put
up a building cheaper than he can rent
one, he puts it up, but he does not figure
that he must make the same profit on
the money invested in his building that
he does on the manufacturing or other
operations of his business. He simply
compares the normal fixed charges on
the cost of the proposed building with
what he will have to pay if he rents
one. Exactly the same procedure should
be followed with reference to the ques-
tion of generating power or purchas-
ing it.

I believe it would be hard to find a
manufacturer who has succeeded in get-
ting a reduction in his insurance through
eliminating his power plant and adopt-
ing purchased power. So long as he
keeps a boiler with fire under it and
requires steam for either heating or
manufacturing purposes, so long will
his insurance rate remain practically
the same as it was before he removed
his engine.

With reference to labor, that of the
fireman or part of it may be eliminated
by the substitution of central-station
service, and it may be possible to
do away with the operating engineer,
but some one having engineering knowl-
edge and experience must be kept on the
pay-roll in order to see that the plant
is operated efficiently, and that the gen-
eral transmission apparatus is kept in
good order.

Executive attention will not be elim-
inated. With a properly designed cost
system, and a report sheet from the
power plant, the executive attention re-
quired by an isolated plant is very small,
particularly if the engineer is a good
one; if he is not, a good deal of execu-
tive attention may be required, hut it
speaks very poorly for the executive if
a poor engineer is allowed to hold his
position long. With power generated

August 22, 1911

POWER

287

at the plant, a very few minutes each
day will enable the executive head to
keep close track of the coal used, the
power generated and water evaporated
per pound of coal, and the cost of power
per unit of production; the general work
of the clerical force will be compara-
tively small. With power purchased,
the same executive attention would be
required if a plant were properly oper-
ated, because the executive head should
know how much power is used from day
to day, and how much per unit of output,
as this would give him a line on the
general behavior of the machinery
throughout the plant and the cost per
unit of output; practically the same
amount of attention would be required
from the clerical force. In addition to
this, either the executive head or some
one else would have to check up the
bills rendered by the power company,
and those of us who have had experi-
ence in checking up bills on a sliding-
scale basis, which is so commonly in
use, realize that it is by no means an
easy job. Thus it would seem that the
executive attention required when using
purchased power would be quite equal
to that required for isolated-plant oper-
ation.

The loss in productive capacity is
pretty hard to figure. It is my opinion,
based on some years of observation and
experience, that an isolated plant, well
built and cared for, is quite as free from
shutdowns as any equipment operated
from central-station service; in fact, it
can be made much more satisfactory
than much of the central-station service
of which I have had knowledge.

The value of auxiliary service depends
entirely upon the method of operating
an isolated plant. With shaft and belt
transmission, it is frequently hard to
operate any single department without
driving a great deal of useless shafting,
but separate department operation is, as
a rule, very infrequent, and in most
plants it is found that but one or two
departments require overtime service,
and usually the same departments, so
that it would be a comparatively easy
matter to install motors to operate this
portion of the plant on a pinch, supply-
ing the power from the generator used
for lighting purposes.

It would seem, therefore, that for
the most part these arguments for
bought power are not really of much
importance, although they frequently can
be made to appear so by the central-
station expert. A careful analysis, how-
ever, of central-station claims in com-
parison with what can be done in an
isolated plant will usually result in
these arguments being demolished.

The central-station salesman also fre-
quently makes the statement that the
cost of heating by exhaust steam is
equal to or greater than that of healing
by live steam, as the back pressure on

the engine resulting from the use of ex-
haust steam compels the use of more
steam for the engines than they would
otherwise use; the argument has also
been advanced that the heat in the ex-
haust steam is not sufficient to warrant
using it for heating purposes, as it will
not give effective results. They further
claim that it is better economy to use
a condensing type of engine, using live
steam for heating, than to operate a non-
condensing engine, using exhaust steam
for he.iting. AM of these arguments need
careful consideration.

In the first place, there is no necessity
for any back pressure on the engine,
with a properly designed heating sys-
tem. In the second place, exhaust
steam is quite as efficient for heating as
live steam, with a properly designed
heating system. The very slight differ-
ence between the temperature of steam
at 5 pounds gage and that at atmospheric
pressure is not worth consideration ex-
cept under very special conditions.
The question of running condensing or
noncondensing is entirely apart from the
question of heating, and it is settled en-
tirely upon the basis of whether the
amount of coal saved by running con-
densing will pay for the additional ap-
paratus installed and the additional water
required for condensing purposes.
Under most conditions exhaust steam
is most economical, for a large percen-
tage of the factory plants find it more
economical to run condensing than non-
condensing. The central agents claim
that as much more coal is required to
operate the heating system under these
conditions as would be required to oper-
ate the heating system if the engine
were not in operation. Any one who
has ever analyzed this question fully
will appreciate the absurdity of such
a claim. If the exhaust steam is just
equal to that required for the heating
system, the cost of the coal can be con-
sidered as the cost of heating, thereby
reducing the cost of the power by just
that amount. As the amount of steam
used by the engine increases beyond that
required for heating, its value as a
heating medium will decrease until if
the steam used for heating is a negligi-
ble amount as compared to the total
steam used for the engine, then the ques-
tion of heating is entirely eliminated
from the cost of power operation at the
plant. This is a condition rarely, if
ever, reached.

The whole general method of attack
by the central-station salesman on the
isolated plant is open to criticism, and
the only reason that they succeed in
many cases is that the plan* owner or
manager is, as a nile, not a power ex-
pert, though he may be a good business
man. and understand how to flgure what
if costs him to produce his goods and
at what price he must sell them to make
a profit. His power plant Is usually

left entirely in the hands of his engi-
neer, and while he is interested in mak-
ing a saving in his power plant, he has
neither the time nor the knowledge to
detect the weak points in the arguments
of the central-station experts, who are
trained in formulating plausible argu-
ments. Many power plants have been
displaced, by central-station power upon
reports which, if carefully analyzed,
would show far greater opportunities
for saving in other directions than by
adopting central-station power; not a
few of them have been discarded en-
tirely through the influence of that ab-
solutely unjustifiable factor, profit ratio.
An illustration of the methods em-
ployed by the central-station experts is
afforded by a report form used for
securing factory loads for central sta-
tions, which was described by Mr. Perry
in a recent issue of The Electric journal.
The form is an excellent one, but the
material used and the results derived
are open to much criticism. Mr. Perry's
filled-out report describes a power plant
of four 200-horsepower Heine boilers,
installed in 1901; a Corliss engine,
36x72, also about 10 years old, belted
directly to the line shaft, and the neces-
sary auxiliaries. The engine indicated
520 horsepower average, 615 maximum,
and a minimum of 470. The friction load
of engine, shafting and loose pulleys
was 260 horsepower. The report states
that the evaporation of 5.2 pounds of
water per pound of coal was being se-
cured, the coal being a half-and-half
mixture of pea and Pocahontas. In
order to burn this coal forced draft was
necessary, this being furnished by means
of a 7x8 Ajax engine driving a Sterling
blower. It is interesting to note the
rate of evaporation, and the fact that
four boilers of 200 horsepower each
were required in order to furnish steam
for a Corliss engine with a maximum
load of 615 indicated horsepower. What
type of a man was the engineer who
would allow a Heine boiler to get in
such a condition that it would only
evaporate 5.2 pounds of water per
pound of coal, and who would consider
for a moment the necessity for operating
four 200-horscpowcr boilers to furnish
steam for 615 indicated horsepower in
a Corliss engine? Evidently neither
the manager nor the engineer was ac-
quainted with his work. If these boil-
ers had been kept clean an evaporation
of 10 pounds per pound of coal would
have been practicable; the steam could
have been mad« by two boilers, and the
coal bill reduced one-half; this would
also allow the elimination of a fireman.
It is quite evidcn( ., A the first medi-
cine required in this plant, according
to the report itself, was not central-sta-
tion power, but a new engineer. It is
reasonable also to assume that if the
boilers were allowed to get In the con-
dition indicated, the engines and heat-

288

POWER

August 22. 1911

ing system were quite as bad, and prob-
ably all work throughout the plant
which came undei this engineer was
equally bad. Nothing was said in the
report to indicate any necessity for im-
provement in the condition of the steam
plant.

The report states that under the pres-
ent condition of operation the executive
attention costs about S500 a year, where-
as under the head of central-station
power no charge is made for executive
attention. Earlier in this article I have
called attention to the necessity for ex-
ecutive attention in both cases.

Under the head of "Loss of Pr.oduc-
tion," the report gives an item of forced
shutdowns aggregating about one day
per year at a cost of S500 per year in
production labor alone. After consider-
ing the conditions noticed at the boilers
it is not hard to understand that there
would be forced shutdowns. The won-
der is that there w-ere not more of them.

Under the head of "Motor Drive."
there are specified motors to the capa-
city of 572 horsepower, with the erection
and wiring, at a total cost of S5927. It
is pretty hard to see how motors could
be purchased and installed, with the
wiring, at this price, even though the
installation were made by the millwright
force of the plant. Certainly the time
of these men should be charged up to
this work, and the motors, unless pre-
sented by the power company, would
probably cost considerably over S4527,
unless they were of a type totally un-
fitted for the work, which not infre-
quently happens. The central-station
agent is very anxious to make the cost
of the installation as low as possible,
and he therefore recommends the use
of the highest speed motors obtainable,
frequently disregarding the fact that
these motors are by no means economi-
cal in their operation, owing to the very
short distances between shaft centers
often necessary in factory plants.

Under the head of "Factory Heat-
ing," the report states that exhaust steam
no longer being available, low-pressure
live steam will be used, and the amount
of coal required for factory heating and
for the dipping department will be com-
puted with reference to the radiating
surface. "Comparing this factory with
others whose coal consumption for heat-
ing is known, we would assume that 510
tons of coal per year would be required."
This item is absurd on the face of it.
The question here is not what other
factories have done, but what this fac-
tory is going to do. The factory has
baen generatir- -am at the rate of
5.2 pounds pei pound of coal, and
therefore the coal required to make
steam for heating must be based upon
an evaporation of 5.2 pounds and not
upon an assumed evaporation of 8, 9
or 10, as is done in other factories.
Under these conditions the coal bill will

be, at the lowest estimate, twice the
quantity assumed, and it is pretty evi-
dent that an engineer who would allow
the evaporation to fall to 5.2 pounds is
likely to have a heating system which is
decidedly inefficient, with the result that
the coal bill for heating is more likely
to be three times the estimated value
than twice.

The final results of this report are
highly interesting. According to it. the
total annual cost of light, heat and power
as at present produced is $28,347. The
cost of central-station service is given
as S23,324, or a saving of S5023. To
this, however, as outlined above, we
should have to add S500 for executive
attention and S4000 for coal, reducing
the total saving to $523.

What would be the saving if the plant
were operated in the hands of an engi-
neer who knew his business? His first
duty would be to overhaul the boilers,
which would result in a saving of one-
half the coal, cosfing S7500. He would
next get rid of a fireman, saving ap-
proximately $800, or making a total
saving of $8300, and he would undoubt-
edly make numerous other savings by
bringing the plant into a proper condi-
tion as to both power development and
heating. It is clear, therefore, from
a careful consideration of the report,
that a much greater saving can be made
by putting the existing plant in proper
condition than by the use of central-sta-
tion service.

LETTERS

Cuttin<j[ Out Dynamos in
Parallel

The precautions in cutting out one of
two dynamos suggested by Mr. McKel-
way on page 214 of the August 8 issue
might have been necessary fifteen years
ago, but I do not think quite such care-
ful nursing is necessary with modern
machines. Railway generators are sub-
jected to instantaneous changes of load
which are much more severe than that
which caused "W. H. L.'s" governor to
hang up, and lighting generators are
equally able to stand such changes, ex-
cept, perhaps, in the matter of sparking.
Even in this respect, a modern dynamo
that would not take an increase from
one-third to full load without giving
trouble would not be considered a first-
class machine.

By the foregoing I do not mean to
intimate that shifting some of the load
before cutting out a machine, as sug-
gested by Mr. McKehvay. is a worth-
less refinement; on the contrary, it is a
good thing to shift most of tl.e load in
order to avoid dealing unnecessary sud-
den shocks to the engine as well as the
generator armature. But I do not con-

eider it necessary on the ground of
sparking.

Francis W. Appleton.
Baltimore. Md.

What DispJatcd the Brush
Holder?

On going to work a few nights ago I
found the day engineer industriously
sandpapering the commutator of what
was once a 35-kilow3tt belted generator
but has been changed into a motor and

Pigtail

Fig. 1. Type of Brush a.nd Holder Usei>

is driving a 9x 13-inch ammonia com-
pressor. I found upon inquiry that the
trouble was caused by one of the brushes
becoming displaced from its normal posi-
tion. The brush holder is of the pivoted
type represented in Fig. i, a cast-brass
arm A being mounted on the stud B
so it is free to turn on the stud. The
brass tension spring S is fastened to a
clamp collar C which is also on the stud
B and is clamped to it by tlie screw D.

The brush holder, by some unknown
means, became thrown over to the posi-
tion indicated in Fig. 2 and the results
were a badly burned commutator and a
shutdown. The pigtail was burned off at
the point of attachment to the collar and

Fig. 2. Position in Which Brush
Holder Was Found

the main circuit-breakers blew out, put-
ting the whole system in darkness.

There was no one in the engine room
at the moment, so far as we know, the
engineer being in th« boiler room, and
we are unable to account for the dis-
placement of the brush holder. If any
other reader has had a similar experi-
ence and can give an explanation of it,
I will appreciate the information.

EdCiAR .\lt.m.\n.

Cincinnati, O.

.August 22, 1911

POWER

289

Kj 1 .3. t.

Apparatus for Passing Gas

Samples to a Calorimeter

By O. C. Berry

Mr. Parmely's article in a recent num-
ber of PovcER describing the use of a
water aspirator for taking samples of
gas from a suction gas producer for
delivery to a Junkers calorimeter was
read with much interest by the present
writer. Under the special conditions ex-
isting in the case cited, the water used in
the aspirator had probably just been
through the wet scrubber and, conse-
quently, was partially saturated with the
g2S. If that was true, the error in the
results obtained may have been com-
paratively small, but in general, using
an aspirator for such a purpose would
lead to an error of important magnitude,
because water absorbs a considerable
portion of the ronstituents of producer
gas.

Producer gas, of course, is a mixture
of several individual gases, chiefly car-
bon monoxide, hydrogen, carbon dioxide
and nitrogen, with some methane and
negligible quantities if oxygen and ethy-
lene.

According to Hempel's "Gas Analysis,"
one cubic foot of water will absorb five
of these gases to the following extent,
at 20 degrees Centigrade: Hydrogen
0.01819 cubic foot; carbon dioxide, 0.9
cubic foot; carbon monoxide, 0.02312
cubic foot; methane, 0.0349812 cubic
foot; ethylene, 0.1488 cubic foot. Each
of these figures is the quantity of gas
that the water will have absorbed when it
has become saturated with that gas, the
gas itself being at atmospheric pressure
and 20 degrees temperature.

To ascertain the amount of each gas
that the water can absorb from the mix-
lure representing producer gas, each of
the foregoing fgures must be multiplied
by the percentage which the correspond-
ing gas represents of the whole.*

The volume of gas delivered by a
water aspirator per cubic foot of water
used will vary with the decign of the
aspirator, the water pressure and the
pressure against which the gas is de-
livered. The aspirator investigated in
the laboratory at the University of Wis-
consin will deliver about half a cubic
foot of gas per cubic foot of water used,
the water pressure being 60 pounds per
'<quare inch and the gas being delivered
against a back pressure of about 10

inches of water. Using these figures as
the basis of computation, the effect that
the absorptive qualities of the water
would have upon the composition of the
gas would be as shown in Table 1, for
producer gas of the composition stated
in column 1. The volume of each

one might expect, but it is quite appreci-
able. In the particular case cited above
it would be as shown in Table 2, all of
the heat values being reduced to zero
Centigrade and 29.92 inches of mercury
pressure, and the lower heat value of
hydrogen being taken.

The absorptive effect of the water is
obviously greatest in the case of the
CO, which will ordinarily be removed
almost if not entirely. The change in the
heat value of the gas will therefore be
affected most by the percentage of CO
in the original gas; it will also vary with
the number of cubic feet of water act-
ually used in aspirating 1 cubic foot of
gas and the degree of saturation of the
water before and after its contact with

1

Gas

Per Cent, b.v
Volume

.1

Coelticif lit of
.Solubility in
Water X 2

Voluini- Su\-
ubl.- ill -J Cii.
I't. of Wilier
fiuliT Partial
Pressun-

Volume of

(ia.s Ix-ft

Unali.sorhed

6

Percent, by
Voiuino in
Final f\as

CO,

00

to

20

8

3

OS

0 a
.-.SO

1.8

0.046

0.036

0.070

0.30

0.0

0.0

18.0
0.92
0.29
0.21
O.l.i
0.0
0.0

0

19.08
7.71
2.79
0 3.T
0 50

.18.00

0

H

S 72

CU,

••,ri. ...:.:.::::.::

(),

0 .'>6

.\

6,i -,9

ss 43

100 00

gas that can be absorbed by 1 cubic
foot of water is multiplied by 2, in order
to obtain the figures in columns 3 and
4, because 2 cubic feet of water are
required to aspirate 1 cubic foot of the
composite gas. The reason for not
figuring on any of the oxygen or nitro-
gen being absorbed is that the water
used in the aspirator will in every case
be saturated with air and will therefore
not be capable of absorbing either of
these gases.

the gas. The error obviously may be
important and it is one for which cor-
rection cannot be satisfactorily made,
even approximately.

There are, however, two methods that
can be used to draw gas from a suction
plant without entailing the error de-
scribed. Fig. 1 illustrates the apparatus
for applying one of these; this equip-
ment is the easier of the two to 'ps'all.
It consists of a small gasometer, the
tank of which is about 2 feet in diameter

Gu

Per <!cn(. by

Volnme.
OriKinal ('.■»

Per Cent . b.v
Volume,
nnal (iaa

Il.t.n. |KT

Cii.Kl. of

Can

B.l.u. in
Original Can

n.l.ii. In I'inal
Can

CO

>>>

20 n

21 a
8 7
3 2
0 4

342
298
064
1.173

88 40
23 84
28 92
7 68

73 87
2.'i 93
30 .H.-.
6 2(>

Total

129 03

lae 04

From the figures in the table it is
evident that the gas that reaches the
Junkers calorimeter may be very difTcr-
cnt from that which flows in the producer
main. The effect that this change in
chemical composition will have on the
heat value of the Ras is not so great as

flnd ^ feel high and the "lift" is provided
with a nozzle to take a small hose con-
nection. This connection leads through
a tec to the gas main and to the caloii-
mcter. as indicatel in the sketch.

To operate such an outfit the Irnk is
filled with water that has been sat irated

290

POWER

August 22, 191 1

with the gas. To saturate the water, a
quantity of gas several times the volume
of the water must be bubbled through
the water, or water that has just been
through the wet scrubber can be used.
Then the lift is immersed in the water
so deeply that all the air is driven out
of it and the water level is up to the con-
nection for the rubber tube. The rope
for raising the lift is then run through

To Gas
Main

Fic. 1. Simple Apparatus for Taking
Gas Samples Intermittently

the pulleys above and a weight somewhat
lighter than the lift is hung on the other
end of it. Next the pipe leading to the
Junkers calorimeter is closed off, the
one connected to the gas main is opened
and the gasometer lift is allowed to take
in the desired amount of gas. When
this is done the weight is removed from
rope, the valve in the pipe to the gas
main is closed and the one in the calori-
meter pipe is opened; the weight of the
lift will force the gas through the
calorimeter.

When this charge has been tested,
the operation can be repeated, of course,
but samples cannot be tested much more
rapidly than three times an hour if each
test is checked by making two determl-

set up. It consists of a small water-
scaled plunger pump and a receiving
and pressure-equalizing tank, con-
nected up as represented in Fig. 2. The
pump may be belt-driven, as indicated by
the presence of the pulley, or operated
by any other convenient means. It
should be of such a size and operated at
such a speed as to be able to give a
theoretical displacement of about Yz
cubic foot per minute. The actual de-
livery of gas will be considerably less
than this on account of slippage, but the
pump should be driven fast enough to
deliver not less than a cubic foot of gas
to the calorimeter every five minutes.
The equalizing tank is provided with a
waste outlet which can be adjusted to
take away any excess of gas delivered by
the pump.

The motion of the pump plunger
causes the column of water to recipro-
cate and this really forms the pump for
the gas. The check valves in the inlet
and discharge pipes operate in the ordi-
nary way. The water plunger, of course,
is air and gas tight at the pressures that
would occur in use. The gas pumped is
therefore free from any contamination
due to leaks at the pump. The con-
stant contact with the water in the pump
and the receiving tank keeps the passing
gas saturated. The apparatus, therefore,
contains no inherent source of error, lis
operation is very simple after it is once
installed, and has proven very satis-
factory.

Well Managed Diesel Engine
Plant

By S. KiRLiN

The writer recently visited the power
plant of the Prairie Pebble Phosphate
Company, which is located near Mul-
berry, Fla., and now contains eight pairs
of Diesel oil engines having a rated ca-
pacity of 450 horsepower per pair, with
a possible overload ability of 500 horse-
power. It is said to be the largest plant
in the country in which Diesel engines

the generator is a coupling by means of
which either engine can be disconnected,
leaving the generator to be operated at
half load by the other one at any time
it may become necessary to make repairs
or adjustments to either of the engines.

Arrangements are provided for easily
testing, by means of a water rheostat,
the power that any of the engines is
capable of developing. In a small brick
building adjoining the power house is
a switch panel which contains eight
three-pole switches which are connected
respectively to the main terminals of the
eight generators. From these switches
the current can be passed through meas-
uring instruments to the water rheostat,
which consists of a tank in which the
plates connected to each leg of the cir-
cuit can be immersed, means being pro-
vided for regulating the depth of immer-
sion in order to regulate the load on the
generator. This convenient outfit for
testing makes it possible to keep each
engine up to its highest point of effi-
ciency, and in case any one of the units
shows a tendency to carry less than its
share of the load, it is an easy matter
to prove which engine is causing the
trouble.

A fault which has been frequently
charged against the Diesel engine is its
tendency to break its crank shaft. In
order to guard against any distortion
which might lead to such damage, the
shaft bearings in this plant are kept
lined up accurately. All of the bearings
are carefully checked for alinement at
frequent intervals and any unequal wear
is taken up promptly before there is
any danger of its going far enough to
weaken the shaft. The station has been
in operation for about four years and up
to this time there has never been a
broken shaft or even a hot box on any
of the engines.

In order to get a better distribution of
oil over the surfaces of the piston and
cylinder the chief engineer of the plant
removed the pistons from one of the en-
gines and had an extra groove turned in
the lower end of each about 4 inches

OPERATION DATA OF PLANT

More Elaborate Apparatus for
Continuous Sampling

nations upon each sample. The advan-
tages are that the equipment is simple
and easy to install, and the continuous
contact of gas and water during opera-
tion keeps the water saturated with the
gas and prevents changes in the gas
composition.

The second method requires appara-
'tus that is more troublesome to provide,
but it is continuous in its operation and
therefore more satisfactory when once

Week ended

Total kilowatt-hours

Fuel oil, gallon.s

Fuel oil, gallons per 100 kilowatt-hours.

Engine oil, gallons

Dynamo oil, gallons

Cost of fuel oil

Cost of lubricating oils

Sunplies and repairs

Operating labor

Total weekly expense.

April 7
292,900
25,746

.\pril 14
298,500
22,218*

7.44
148
1}
S608 . 35

April 21
284,700
23,982

8.42

399

II

S.i31.90

108.43

26.35

350 . 55

Sl.017.23

April 28
294,600
24.528

8.33
447
li
$525.60
121.51
44.32
335.25

.\u"Tregate Uilowatt-hours for the four weeks.

-\^'i;r;gate expenses for the four weeks

Cost of operation per kilowatt-hour, average.

.1.169,800
84,123.24

3 525 mills

*The fuel oil used during this week w-as of bettei quality than the regular crude oil and cost
$1.15 per barrel of 42 gallons as against 90 cents for the latter.

are used exclusively. Each pair of en-
gines is coupled to a 300-kilowatt three-
phase 60-cycle alternator, located be-
tween the two engines. On each side of

below the point where the gudgeon pin
passes through. A snap ring was fitted
in this groove to act as a wiper and to
retain the oil which would otherwise

August 22, 1911

POWER

291

trickle down out of the end of the cyl-
inder. This expedient resulted in such
a decided improvement in the condition
of the pistons and rings that all of the
others have since been fitted up in the
same manner. In the four years that
this plant has been in operation it has
not been necessary to bore out any of
the cylinders.

The company operates a trolley line
12 miles long, which connects with all
of its various mines, the ore being
hauled to the washers and drying plants
with electric locomotives. In addition to
furnishing current for operating this
trolley system the power plant also fur-
nishes power for operating all of the
motors in the washers, drying plants,
and driving a large number of cen-
trifugal pumps in the various mines.

Preparation is now under way for
doubling the capacity of the power plant
by the addition of eight- pairs of engines
and eight generators of the same size
and arrangement as the units now in
service. The new units will be set in
line with the present ones by extending
one end of the power house.

Through the courtesy of James W.
East, chief engineer of the plant, the ac-
companying operation data are presented.

Test of a Blast Furnace Gas
Engine

A test run of I'j hours was recently
made on a twin-tandem Snow gas engine
running on blast-furnace gas at the
Youngstown works of the Carnegie Steel
Company, with the results stated in the
accompanying table. The cylinders are
42 inches bore and the stroke is 60
inches. The speed of engine was 83 'j
revolutions per minute; the piston speed,
therefore, was 833 feet per minute.

SfM.M.AKY flK TKST RKSII.TS
Full load ratine, kilowatts... 2. linn

AveraBC loail. Itllowatls 2.ino

Avpragc lo.nfj. brako horse-
power n.ono

Cubic feet of gas per hour... 201 .ORO

nt u. per cubic fool of gas. . . SB.62
Il.t.u. per hour In the gan.... 25,21. I.S.'.d

H.t.ii. per kilowatt-hour 11. .">i:!

B.l.u. per brake horsepower-

bonr S.lfiO

KITIrlencv of generator '.p."i''r

Brake thermal efflrlency ."il/J'r

Overall IhTmal efllclenry In

pow<r delivered at awlfch-

f»onrd 2M.<'>''^

CORRESPONDENCE

Vapor Lock in a Fuel Oil

Feed Pipe

A small three-cylinder stationary en-
gine running on benzol was supplied
with fuel under pressure because it
was inconvenient to put the benzol tank
high enough up to obtain gravity feed
to the carbureter. It was found that
the engine, which was hand regulated,
would be "starved" of fuel and run
spasmodically and often stop if it was
attempted to run it slowly or with little

load. If, on the other hand, a consider-
able load was being carried and the
throttle was opened out, the flow of ben-
zol to the carbureter was uninterrupted.
After much head-scratching on the part
of the staff it was discovered that the
cause of starvation was that the feed
pipe had been»farried over the top of
the engine exhaust pipe on its way to
the carbureter, presumably in order to
assist vaporization by heating the fuel
oil, and that the benzol had vaporized
in the loop and the vapor pressure had
caused a lock when the flow was only
what was required for light running. If
on load, the flow was too rapid for this
amount of vaporization to take place.
The feed pipe was shortened and al-
tered to a gradual slope up from the
tank to the carbureter and no further
trouble was experienced.

John S. Leese.
Manchester, Png.

The Heavy Oil Entjine

I have read with more than usual in-
terest the editorial on "'The Oil Engine"
in the issue of Povi er for June 6. It is
quite evident from a consideration of the
recent papers presented before engineer-
ing societies that the development of the
Diesel type of oil engine is progressing
rapidly in Europe, while in this country
it is so little used as to be practically
unknown. It has been said that the rea-
son why America has more or less
ignored the Diesel engine was that coal
was so cheap that the Diesel could not
compete with the steam engine, and that
gasolene was so cheap that there was no
market for the oil engine. It seems to
me that it would be better to say that
their general use in this country has
been prohibited more by their high initial
cost per horsepower installed and the
high cost of maintenance which has been
reported from the first installations than
anything else.

There is hardly any doubt that in cer-
tain fields where its manifest advantages
more than compensate for its extra ex-
penses, the Diesel engine will have much
success, especially in the larger horse-
powers, but for general industrial use in
small horsepowers it is hardly possible
that it will be widely used, because the
gain in fuel economy does not offset the
charges on the initial outlay and the
later maintenance charges.

It seems that what wc need very much
in America is an oil engine which op-
erates with only a fraction of the com-
pression of a Diesel and atomizes the
fuel mechanically, that is, without a com-
pressor. Of course, in such an event
the ignition would have to be effected
by a hot bulb or some similar device.
There are on the market several oil en-
gines working with compressions of from
75 pounds to 1.'^) pounds and there seems
to be no good reason why the compres-

sion cannot be raised to a higher point
and still avoid the use of such auxiliaries
as the compressor.

I understand that an engine has been
recently designed to work with a com-
pression considerably more than that of
the ordinary oil engine but still only
about one-third of the Diesel compres-
sion. There is every reason to believe
that such an engine will have a higher
fuel efficiency than the ordinary oil en-
gine and, in fact, will probably closely
approach Diesel fuel economy. Apparent-
ly it will fill the gap which has existed
between the high-compression oil en-
gines represented by the Diesel and the
low-compression oil engines as repre-
sented by the vast majority.

John S. Nicholl.

Sharon, Mass.

[Engines working with compressions
of from 150 to 300 pounds pressure have
been built in this country several years,
but mechanical atomization of the fuel
appears to have been .found impractical.
It has been tried faithfully and discarded
in favor of compressed air.

Any modification which entails the use
of an auxiliary device for igniting the
charge would be a step backward ; as we
pointed out editorially in the June 13
issue, the absence of ignition devices is
undoubtedly one of the chief factors in
the success of the Diesel engine. —
Editor.]

Trouble from a Long Exhaust
Pipe

The owner of a feed store bought a
3-horsepower gas engine which had been
used for about one year, for the purpose
of running an elevator. The man who
sold it helped to set it up, but when
everything was apparently ready, the en-
gine failed to respond. Everything was
gone over very carefully and the seller
said he could not see why it would not
run, as it had "worked fine" on the pre-
vious job. I was called in to see what
I could do and after a couple of at-
tempts to start I concluded it was an-
other case of a clogged exhaust pipe.
Upon disconnecting the pipe from the
exhaust outlet the engine ran all right,
but 1 was unable to find any obstruction
in the exhaust pipe and as there were
no elbows or turns in it, it began to look
mysterious. The pipe extended straight
up from the engine through the sec-
ond story and on through the roof about
two feet. We then concluded that the
length of the pipe was too great for the
engine, and made connections so as to
run it out of the side of th4 room; then
the engine ran all right.

Can anybody explain why the long
exhaust pipe prevented the engine from
running?

H. H. Delbert.

Titusville, Pcnn.

292

POWER

August 22 lyil

Homem;ide Water Ejector

An erector who was sent about 1200
miles from the factory to erect and start
a new 500-horsepower Corliss engine,
laid out the foundation excavation care-
fully and pushed the digging until he
struck water, then the work went for-
ward with much less speed.

He tried small tin waterspout hand
pumps, but two men working them day
and night made no headway. Then he
rented a diaphragm wrecking pump from
the city water company, but still the
water stood practically stationary at
about 3 feet below the floor level, and he
had to go 10 feet below the floor.

As this was a new plant it was im-
possible to get steam; even the gasolene
engines, which had been used for mix-

long radius elbow at the upper end and
all were lowered into the water and the
city pressure was turned on, but no water
was ejected. The hose was shortened as
much as possible, but this did not im-
prove matters. By tapping the side of
the pipe with a light hammer it was
found that the water in the pipe came
nearly to the discharge point.

f Pipe LockNuf

2fO% Pipe Bushing

%f0 2 Reducer/
Coupling

■g Holei for
holding Lead
2 Pipe Tee

..Tofit 2 Pipe snugly Loose Fit

oawn in fwo here

HOME.MADF- VCaTER Ej ECTOR

ing concrete, had been moved away.
Finally the erector remembered having
read of a water siphon being made out
of pipe fittings to operate with water
pressure. He had an ample water sup-
ply right in the engine room from the
city pumping plant and under a good
pressure, so he went to the only steam-
fitter in that town and told him in a gen-
eral way what he wanted. The fitter
seemed to know all about such things
and promised to have the ejector ready
at seven o'clock the next morning.

In Fig. 1 is shown the fittings which
formed part of this ejector. A piece of
I-inch hose was coupled on at A. At B
a 2-inch elbow was screwed on, point-
ing upward, and a piece of 2-inch pipe
about 7 feet long was bent to form a

He next determined to line the dis-
charge nipple with lead, as shown at
D, using the wooden core made as
shown at £. Care was taken to file the
end of the jet nozzle C. The ejector
was then put together and tried with
satisfactory results. A solid stream of
water was ejected from the 2-inch pipe
with considerable force, and the water
level rapidly fell in the excavation. The
ejector was kept in a small sump about
6 inches from the bottom. The whole
secret lay in knowing how to make the
discharge nipple, which evidently the
steamfitter did not understand, for one
of the funny incidents of this experi-
ence was that he went to see how it was
working and talked most enthusiastically
about it. When told that it would not

work, he insisted that it must have been
because it was not connected up prop-
erly.

F. W. Sal.mon.
Burlington, la.

Carele,ssnes.s in the Power
Plant

The best of engineers will become a
little neglectful at times, and some are
naturally careless all the time.

On one occasion, for some reason, a
hard-pine board about 6 feet long, 2
inches thick and 8 inches wide had been
used in a boiler on top of the tubes.
The man who cleaned this boiler evi-
dently forgot that he had used the board
and had put in the manhead without
removing it.

When the boiler was opened for clean-
ing the next time the board was found
in a black mass on the bottom of the
boiler. It had caused no bother but
pieces of it might have got into some
pipe and caused serious trouble.

.Another incident which I recall was
that of making a connection on a header.
The stop valves on each boiler were
closed, but a 2-inch bleeder for the
header was connected to the back end
of the boilers, and the valves in it were
forgotten. The connection was made on
the header with these valves open. No
one was hurt, but if one of the check
valves had failed to close or something
had gotten under it someone might have
been scalded.

Another dangerous practice is that of
going into a boiler with the blowoff valve
open when the blowoff pipe is also con-
nected to another boiler that is under
pressure. A vertical check valve is not
a bad thing to have in the blowoff pipe,
but the great trouble with such safety
devices is that too much dependence
will be put upon them.

E. V. Chap.van.

Decatur, 111.

Dan<rt"nnis Water Column
Connection

.A return-tubular boiler of ordinary'
dimensions was purchased from a cer-
tain boiler manufacturer who desired to
send a man out from the shop to super-
intend the setting up and starting of
the boiler. The buyer, however, pro-
tested, as his experience in handling
boilers extended over many years and
he knew that his own force would not

August 22. 1911

POWER

have the slightest difficulty in installing
and getting the boiler into operation.

Nothing was heard from the purchaser
for about two weeks, when he appeared
at the boiler works in an exceedingly-
bad frame of mind. He proceeded to
abuse the firm and its work and said that
the material used in his boiler was per-
fectly worthless, as the plate over the
fire bed softened and the seam had
opened, and that thej' narrowly escaped
serious trouble.

The boilermaker protested that the ma-
terial was of the best and that low water
evidently caused the trouble. Of course,
no admissions were made that such a
thing could be possible.

To settle the controversy a trip to the
plant was made, and an examination of
the boiler confirmed the boilermaker's
opinion that the water in the boiler had
been low. The operator still insisted,
however, that the gage glass had always
shown plenty of water.

"Where is the top connection ?" asked
the boilermaker.

"Oh, you don't need one," was the
answer; "we never connected it up."

So the fireman was right; there was
plenty of water in the glass.

Edward T. Binns.

Philadelphia, Penn.

Wants Diagrams Explained

The accompanying diagram was taken
from a 20x48-inch Corliss engine, run-
ning at 67 revolutions per minute, with

Homemade Compound
Feeder

All the methods I have read about for
feeding compound to boilers are unlike
the method 1 use.

Compound Feeding Tank

The feed-water supply tank is 30 feet
above the heater. I tapped the pipe
coming from the heater at a point 3
inches from the heater for a 'j-inch
connection a.id set the compound reser-

What Is Fauity with These Diagra.ms:

boiler pressure of 70 pounds and a vac-
uum of 23 inches.

I want to know why the expansion line
does not come down below the atmos-
pheric line. It will be noted that the
release and exhaust line turn up in-
stead of down. The engine runs non-
condensing, without pounding, hut
pounds very badly when running con-
densing.

C. A, Poarch.

Petersburg, Va.

It is estimated by the Geological Sur-
vey of Tennessee that there is yet to be
obtained from the Tennessee. Cumber-
land. Green and Mississippi rivers I.-
O-MOOO of un^'-'eloped horsepower.
Surely this is worth looking after.

voir 4 feet above the heater, the pres-
sure in which is not enough to effect
the feeding of the compound.

The accompanying sketch shows my
method of feeding the compound to the
boiler from a • homemade sight-feed
compound feeder. The cylinder is made
from a 10-inch pipe 2 feet long, capped
at each end and tapped for a gage
glass. The bottom cap is tapped for
a I ' ' pipe, which is 10 inches long
For a distance of 4 inches through the
center the pipe is filled with babbitt
metal. The pipe is then tapped above
and below the metal for the sight-feed
connections for which old lubricator
parts are used.

J. W. Dickson.

Memphis, Tcnn.

Suspending Horizontal Tubu-
lar Boilers by Means of
Hangers

A common practice with horizontal re-
turn-tubular boilers is to support them
by means of lugs resting on rollers,
which in turn rest upon iron plates im-
bedded in the brick setting. This prac-
tice has proved most satisfactory, "nu;
the question which constantly arises in
my mind is why the practice of suspend-
ing boilers by means of hangers from I-
bars is not more generally adopted, such
Es is carried out in setting water-tube
boilers.

Such a method is feasible if I-beams
are run transversely across the boiler
overhead and are supported by steel
columns protected from the heat of the
furnace by the brickwork. This would
bring all the weight on the foundation
of the setting and no strains would be
brought to bear upon the brickwork by
the boiler. By this method the columns
would support the brickwork and the
brickwork would give the columns
lateral support.

In some instances, 1 have seen the I-
beanis exposed to the air of the boiler
room or built into the brickwork so that
the outside surface came flush with the
brick setting. This method, of course,
prevents the column from ever becom-
ing overheated.

It does not seem advisable to build the
columns solidly into the masonry,
especially in the case of two boilers or
more being set in batteries. In such a
case, the columns cassing through the
brickwork forming the setting between
the two boilers would he liable to be-
come overheated and the walls would,
therefore, be warped and cracked.

'A study of this method of boiler
setting reveals three defects w-hich may
easily creep in if they are not guarded
against. The first is that the I-beams
may not be sufficiently rigid or of a
strength great enough to support the
weight that might be brought to bear
upon them; second, the supporting col-
umns themselves may be of a strength
or stiffness insufficient to withstand the
strain put upon them, and third, the
means for preventing overheating may
have been overlooked entirely or the
setting of such design as to render
it incapable of bringing about the prop-
er results.

In cases where boilers are set in batter-
ies of more than two, it will be necessary
to have center supporting columns rest-
ing on the foundation. In order that
this may he kept cool a space should be
built around it in the brickwork.

Ventilation could easily be secured
by allowing the space at the top to re-
main open and space made at the bottotn
of the column to form a sort of air
Jucf, so that there will be a circulation

294

POWER

August 22. 1911

of cool air up through the air space
surrounding the column.

Of course, the size and shape of the
supporting columns and the size and
weight of the I-beams would necessarily
have to be calculated in each instance,
so that they would be of sufficient
strength to support the weight which
would come upon them. This would
require calculation by someone familiar
with determining the strains, bending
moment, etc., of iron and steel structural
work.

L. Holder.

OuiMET, Ont., Can.

Side Play in Cnink Pin

Bras.ses

A practice in engine design which
proves to be troublesome is shown in
Fig. 1. In one instance !4 inch was al-

Sinn Play on Crank Pin

lowed on each side of the crank bearing
for lateral play. This idea did not come
from the engine room, as many engineers
have so faced off the pin of a crank en-
gine as to bring it closer to the sides of
the rod and eliminate the side slap.

Fig. 2. Filed Crank Pin

Many times I have faced off the sides
of a crank bearing and put on segments
to fill up the space brought on by wear.
But here is an engine built with side play
in the crank-pin brasses which will cause
trouble.

In Fig. 2 is shown how I was compelled
to file the pin and fit the brasses.

C. R. McGahey.

Baltimore, Md.

Bafftred Water Tubes

When tubes in water-tube boilers be-
come bagged it is usually but a short
time until they leak and need replac-
ing. Bagged tubes are mostly found
in the rows nearest the fire, and may be
easily reached from the furnace. The
life of the tubes may be prolonged by

driving the bags back into place, as is
done with the fire sheets of boiler shells.

My method is to plug the ends of the
affected tubes to prevent air circulating
through them while they are being
heated. The heating is done with a
gasolene blow torch, which brings the
metal to a red heat in a short time.
The bag is then driven back with a hand
hammer, working toward the center
from the outer edges of the bag until the
tube is round. A tube repaired in this
manner will last as long as those which
were never bagged.

P. L. Werner. '

McKeesport, Penn.

Scale Cause of Low Vacuum

The incident described herewith re-
lates to an experience I had with a low-
pressure turbine. For two months the
new plant did well, barring minor trou-
bles that were easily located. Then the
29-inch vacuum began to drop from day
to day, and in two weeks the turbine was
running with from 22 to 24 inches of
vacuum.

All connections were carefully gone
over and painted, the dry and wet air
pumps were thoroughly overhauled, the
condenser taken apart and examined,
and the atmospheric valve inspected, but
there was no increase in the vacuum.

On starting up one Monday morning
the vacuum failed to build up and it
was a case of having to remedy the
trouble. Chain blocks were rigged up,
the upper half of the casing was lifted
and the trouble was located in the water
seals on each end of the turbine, which
had become incrusted with such a hard
scale deposit that it required light chisels
to remove it. During the trouble the
gages on each water seal had registered
correctly, and as the plant had been in
operation but a short time, it was puz-
zling to locate the trouble as the im-
perfect water seals were not suspected.

This same trouble is sure to happen
again, but profiting by past experience,
there will not be two weeks' work and
worry. The water used is principally
from a lead mine.

W. Turner.

Doe Run, Mo.

Indicator Cord Lock Knot

It frequently happens when indicating
an engine that the operator finds the
drum of the indicator striking at both
ends of its travel. This may occur at a
time when the proper conditions have
arrived for taking a diagram.

The accompanying illustrations show
a knot which can be conveniently
loosened and adjusted. A slip knot is
shown at D. The loop B may be at-
tached to the indicator hook and by ad-
justing the end A the loop B may be
made any desirable length.

The lock knot, shown at £, ser\'es to
lock the loop B after it has been ad-
justed. F shows the knot ready for
action.

In case the cord has stretched or
shrunk, pull out the first loop and make

Fig I

Fig, 3
Stages of Making Lock Knot

the proper adjustment to the loop B,
after which the lock knot can be tied
again.

Charles H. Croo.m.
Detroit, Mich.

Device for Separating Piston
Rod from Crosshead

The accompanying sketch illustrates a
method used for removing the piston rod of
the slot-and-key type from a crosshead.
The wristpin is removed and replaced by
the block A, key B and block C, all resting
on the wooden block D, to keep in posi-
tion. The studs are tapped into the

Details of Separating Device

block C to hold it in position. Very little
trouble is experienced when the wedge
B is driven "home" in starting a rod.
E. S. Hodges.
Medicine Hat, Can.

August 22, 1911

POWER

295

Piston Rings

In the June 20 issue of Power, C. R.
McGahey gives his ideas of keeping
piston rings tight. It looks very much
from the article as if Mr. McGahey is
laboring under the delusion that there is
only one kind of a piston and that must

Fic. 1. Old Method of Making Tight
Piston

be a solid one. Regarding Fig. 1 of his
article, which is reproduced herewith, I
never saw a more elaborate affair for
scoring up a cylinder at the points marked
M.

Again, the cost of the piece *? would
almost equal the cost of a new ring, to
say nothing of the careful measuremjnts
and fitting that would be necessary to
have the angles of the bull ring and pis-

II MUJI

J!' ^Oi

■€i?H

Hi

Fic. 2. Pi.uc AND Spring Method

ton ring coincide to form a good joint.
Regarding Fig 2, also reproduced here,
which shows a heavy spring under the
bronze plui;, thf increased surface and
friction of the plug rubbing against 'he
walls of the cylinder would certainly out

a groove alon;^ the cylinder. And, again,
the mere action of bolting up the follower
plate would cause it to bind unless it
was a ver>' loose f.t and in that case
it would be useless.

I might say that the joint which I
showed in a previous letter and which
Mr. McGahey. without giving any rea-
son, says is a poor apology, is in use for
the severest service that a ring can be
put to, namely, on stamp heads for crush-
ing copper ore. The dimensions of these
are: Cylinder diameter, 24 inches; stroke,
26 inches. They work under 130 pounds
steam pressure and at the rate of 118
strokes per minute.

G. H. Handley.

Newburgh. N. Y.

Air Compressor Running
Under

In the August 1 issue the question is
asked if there is any reason for running
an air compressor under. The answer
states that there is none, and if the ques-
tion refers to a straight-line, steam-driven
machine, it is correct, for the air piston
pulls directly on the steam piston while
the flywheel serves to carry the crank
over the center. There are, however, a
large number of compressors driven by
other power than a steam piston; these
include motors geared direct or belt
driven from some source. Many of these
arc designed with very light crosshead
guides which would not allow of a very
heavy pull, and the makers of these ma-
chines usually advise running them under
so that the pull of the connecting rod
will come in a downward direction on
the frame of the machine.

G. H. KiMBAI.I..

East Dedham, Mass.

A question w.is asked in the August
issue regarding the direction of compres-
sor rotation. In air compressors where
the air cylinders are directly behind the
steam cylinders, running the compressor

under brings the pressure of the cross-
head on the lower guide; running it over
brings the pressure on the upper guide,
the tendency being to lift the machine
from the foundation. This is directly op-
posite to regular engine practice, and is
due to the power being exerted in a dif-
ferent way, which may be readily seen
by following the action of steam and air
in their respective cylinders. It would
seem then that there is a reason for run-
ning a compressor under.

David Billson.
North Chelmsford, Mass.

Putting in Crank. Pins

B. W. Robinson's article, "Pins in
Loose Crank Pins," in the July 18 is-
sue, brings to mind the difficulty of put-
ting in new crank pins in isolated places.

By using a common jack screw and
making a frame to clamp on the disk,

S-J-

Section A- 3

Iack anp Frame for Forcing In Pin

as shown in the accompanying figure, the
pin may be pushed in tight and with ease.

As may be seen, if the frame is pro-
portionately constructed, the pin may be
put in without removing the crank shaft
from its bearings.

Lioin V. Beets.

Nashville, Tcnn.

Filing Kngim-ering '\rtiilfs

Mr. Andrews' method of filing engi-
neering articles, as set forth in his letter
in the June 27 issue, is thorough as re-
gards the method of making out dupli-
cate index cards to be filed alphabetically
under all possible headings, but thorough
cross indexing is laborious and in a
private file can to a large extent be ob-
viated by adopting a suitable system of
classification. I know of other instances
where the scheme of pasting clippings
in a loose-leaf binder is used, but in a
busy offlce where time is valuable and a

296

POWER

August 22, 1911

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August 22, 1911

POWER

297

number of engineers mark clippings,
pamphlets, catalogs, etc., for filing as
they come up, the use of a book has ob-
vious objections.

The filing of clippings from the tech-
nical magazines, papers before engineer-
ing societies, correspondence containing
technical data, blueprints, tables, etc., re-
ports of tests, drawings and similar mat-
ter cannot be wholly relegated to a clerk
or inexperienced office assistant, since
such matters cannot be filed in proper
shape without first being read through
and the contents digested. .An article
on battleships, for instance, may have a
very e,\cellent discussion of some phase
of turbine operation and design, so that
its proper place for the office in question
might be under that heading.

Again, not only should the clipping
or other literature be given its disposi-
tion in the file, as determined by the
most valuable information it contains re-
gardless of its title, but. furthermore, its
position in the file should be such that
it will be among the material on similar
subjects. For instance, an article on
stokers should properly be placed among
material on combustion, although "Stok-
ers" may begin with an "S," while
"Combustion" begins with a "C." Where
a card-indexing system is used, cards
having the same index initial will be to-
gether, while the information itself will
generally be in some sort of chrono-
logical order. The clippings desired may
thus be scattered through half a dozen
bulky books. The trouble with scrap
books is that they do not permit in-
definite expansion at any desired point.

Some years ago the University of Il-
linois published in a bulletin an exten-
sion of the Dewey decimal system of
classification, as applied to engineering
industries, by L. P. Breckenrldge and
G. A. Goodenough, of that school. In
the accompanying chart this system has
been adopted, with considerable exten-
sions in some parts and cutting down in
others, to meet the peculiar needs of the
work in this office.

Take the subheading "Steam Genera-
tion and Heat Economy" f52I.I8. as an
example; this is under "Steam Engi-

ering" 621.1. which in turn is under
Mechanical Engineering" 621, and the
general heading "Engineering" 620. Un-
der "Steam Generation and Heat Econ-
omy" come boilers, fuel and combustion,
boiler fittings, furnace fittings, econo-
mizers, etc. These subdivisions are still
further extended by adding another fig-
ure to the decimal so that a great in-
crease in the amount of material under
any subheading is easily subdivided and
classified.

A chart of this kind gives a compre-
hensive view of the actual filing system.
At a glance, the general heading under
which a clipping should be placed is de-
fennined and then the proper subhead-
ing. Having placed the proper number

on the clipping, the remainder of the
work is purely mechanical. A filing clerk
or boy places it in its proper position
numerically. The simplest form of file
to use is one made up of ordinary manila
jackets, such as are used in the com-
mon vertical files for correspondence,
the individual jackets being given num-
bers corresponding generally to the sub-
headings on the fourth line of the chart.
When a jacket becomes too bulky, its
contents are easily divided and put into
two or more new jackets which are given
appropriate numbers.

When information on some subject
is wanted from the file the chart makes
reference very simple. Suppose, for in-
stance, data are wanted on tests of cen-
trifugal fans. The decimal number for
centrifugal-fan tests is 621.623.2, under
the heading "Blowing and Pumping En-
gines" 621.6. Assume that the file is
of such size that a folder is numbered
621.623; then in looking up the number
621.623.2 on tests, the whole jacket
would, of course, be taken out and arti-
cles which had been filed under "Design"
621.623.1 and also under "Types" 621.-
623.3 (and other subheadings that have
been included in the classification I would
be turned up at the same time. Any
material on tests of fans, although in an
article on some related subjects, would
thus be brought to light. Cross index-
ing is by this means practically elimi-
nated, and the little required is easily
provided by filing a sheet of paper, show-
ing the title and number of any article
filed elsewhere which may contain in-
formation on the subject in question.
Paul A. Bancel.

New York City.

Going Over the Chief's Head

The editorial on the above subject in
the July 25 issue put the matter in a very
good light, but there are times when it
becomes necessary to go higher. How-
ever, I do not favor trying it unless there
is something of great importance at
stake, as the organization of any plant
should center around its head.

Once while in charge of a power plant
I was unable to agree with the master
mechanic on certain matters and gave
notice of leaving. Upon being asked as
to why I wished to leave, this trouble
came out and the treasurer of the com-
pany said that I should have come to him
about the matter. This, however, would
have caused more trouble; the master
mechanic would have distrusted my in-
tentions, and the friction would have
been increased instead of lessened. I
had tried to support him in his work,
and when I found that it was impossible,
I left the employ of the company.

It is firms of thi^ sort which encourage
their subordinate employees to come to
them with stories .iboiit what is going on
inside instead of depending for their in-

formation upon the department heads,
and with the firm in question this has
gone on tc such an extent that the gen-
eral organization of their factory is in
bad condition as regards efficiency.

If such practices work out in this way
in a factory, why not in the power plant ?
The chief engineer who -cannot deal
squarely with his men is not the proper
man for the place because he is a detri-
ment to the organization, as it is plain
that the men will distrust him when he
promises anything better. Here is an
illustration of a man who was assistant
in a mill plant and who, wishing a raise
in wages, first went to the chief engi-
neer, who, after a few days told him that
he had consulted the superintendent and
nothing could be done. Then the assist-
ant spoke to the treasurer, who made ar-
rangements for him to get the increase.
In one or two other instances this same
procedure succeeded. The main result was
gained, but the assistant did not feel that
his immediate superior valued him highly
enough to even try to give him more, and
it was left for the higher official, who
WES not in a position to judge of his
qualifications intelligently, to give him
what he asked. In the same plant one
of the fireman who had proved his worth
over any man they had had in that capa-
city for some time, asked for a slight ad-
vance in wages. He did not get it; he
did not try to go around his chief, and
as he was disgusted with the treatment
he had received, he left shortly after and
his loss was felt for some time to come.

In a case like this, where the chief is
so lacking in the moral requisites that
go to make up a good man. and who
showed no vexation when a matter was
ordered over his head that should have
been attended to by him, it is permis-
sible to do as the assistant did.

From the foregoing it is apparent that
any man in charge of a power plant, to
succeed, must have such control over his
assistants that they will not go over his
head; neither will they try to do so if
he uses them fairly. If any do. without
going to him first, they should be dis-
ciplined, and any manager who encour-
ages this practice is only making trouble
for himself.

G. H. Kimball.

East Dedham. Mass.

Performance at Redondo
Plant

Since 1P08. Povi ek readers have waited
patiently for a report of the individual
boiler tests made at the Redondo. Cal..
plant of the Pacific Light and Power
Company, closely allied with the of-
ficial test of the complete station.

PnnER itself, in October. ipnp. page rtfi3.
commenting upon a sixteen months' rec-
ord at the plant, concluded with re-
marks that exhibit the united opinion
of many of its readers, stating. "No in-

298

POWER

August 22, 1911

formation is as yet available as to the
separate efficiencies of the boilers and
engines, and this is looked for with un-
abated interest." We are still looking,
still waiting.

Mr. Brian, then chief engineer for
the company, and one of the "favored
few" to see a report of these tests,
gives us the following information:
Sixty-one tests were made on boiler No.
6, equipped with style "D" Leahy rear-
end burner, and Peabody's patent fuel-
oil burning furnace, the same as used
during the sixteen months' operating
record published in Power. The result
of these tests gave an efficiency of ap-
proximately 86 per cent., the highest
ever obtained under like conditions, and
constituting a record.

With this to "excite us," is it any
wonder that we are anxiously waiting?

In Po\xER for May 9, 1911, we are
accorded a synopsis of a series of seven
tests on one of the boilers, made in the
present year, but with ditferent type of
burner and furnace from that mentioned
above; this test states an average effi-
ciency of 80.47 per cent. Why does this
supersede in print the original test, es-
pecially when the efficiency obtained is
lower?

Boiler efficiency usually interprets
generating economy; Power's published
figures in 1909, attested by officials in-
terested in the plant, give 235.64 kilo-
watt-hours per barrel of oil in the test
of the complete plant, and 220.59 kilo-
watt-hours per barrel of oil as an aver-
age for actual operation for sixteen con-
secutive months. No public record has
been furnished of output per barrel of
oil during the early months of the cur-
rent year coinciding with the period of
the test mentioned; Mr. Brian states that
for the month of April this approximates
207 kilowatt-hours, average.

With last week's full description of
the enlargement that has recently been
made of Redondo, Power's files stand
complete with this plant, save for the
instance noted, and what would reason-
ably appear to be .one of the most in-
teresting and instructive items connected
with the work.

Leon ."Xlias.

Los Angeles, Cal.

Isolated Plant Management

I fail to see wherein the central sta-
tion should bother the encinecr who has
a half-way decent plant and is operating
it creditably. It is every engineer's duty
to know what his plant is doing, and if
he has not the proper .facilities he can
■by the exercise of good judgment make
a creditable showing if ht does not get
tired and allow thirg<- to go their own
way.

His boilers should be kept clean in-
side as well as outside, the combustion
chambers, as well as tubes must be

scraped frequently, and he should lo-
cate all the leaky joints in the boiler
settings and plug them with asbestos
and filling outside with cement; prevent
all leaks in flues and clean out doors
that are admitting air; keep the feed
regular, and have a sane method of fir-
ing. No set rule can be made for this
work as the conditions vary so much.
The feed pumps should be closely
watched to know that the piston and rod
packings are tight and the valves are in
good condition; that the pumps (es-
pecially if they are duplex pumps), do
nfct short stroke, and it must be remem-
bered that if a pump short strokes it
takes the same amount of steam to op-
erate it as though it ran full stroke, al-
though it is pumping an amount of water
proportionately short of the amount it
should discharge were it making its
proper lengtn of stroke. Consequently to
pump its proper amount it must make
more strokes; this not only takes more
steam than it should, but uses more oil and
wears the shoulders in the cylinders by
not traveling over the bore of the cyl-
inder into the counterbore. In a duplex
pump this short stroking can easily be
remedied by packing all the rods and
water pistons carefully and giving a
proper amount of lost motion to the
valve gear. More lost motion makes
the stroke longer and less lost motion,
of course, shortens the pump stroke.

The temperature of the feed water
should be carefully looked after. The
engines should be taken care of and the
valves kept correctly adjusted and ex-
amined frequently for leaks. The pis-
tons should be examined at least every
six months for correct adjustment as
well as for tightness of rings and in-
spection made of cylinder walls.

If these matters are properly attended
to, and the machine well lubricated while
in service, there is very little chance
for trouble and no danger of the plant
being superseded by outside service. A
log should be kept of the plant so that
the engineer as well as the management
may know the cost of the service per
kilowatt- or horsepower-hour. This log
should also include the cost of coal,
oil, waste, repairs, help, interest, etc.;
in other words, the total cost divided by.
the unit output should be known or
easily ascertainable on short notice.

WiLLIA.M S. TrOFATTER.

Somerville, Mass.

The Cornell System

In the July 4 issue of Power an arti-
cle entitled "The Cornell Economizer"
attracted my attention. As some of the
statements contained in it are the same
as those made by all manufacturers of
steam-jet blowers used under boilers, I
fail to see where the Cornell system im-
proves over the ordinary steam blower,
as this system is nothing more than a

steam blower. The claim that by using
it larger quantities of heated air are in-
jected under the grate is the identical
claim made by all manufacturers. There
never was any doubt in the minds of
practical engineers but that a boiler rat-
ing could be increased by applying a
steam-jet blower or a fan to force
air into the ashpit. But the cost
of using a steam jet is generally taken
to be from I'i to 10 per cent, of the
steam generated, and when this is sub-
tracted from the increased evaporation
of the boiler it leaves a narrow margin
for economy. The cost of installing a
steam jet is very small as any practical
engineer can make and install one for
SIO, but the cost of installing a Cornell
economizer should put any manufacturer
on his guard if the price is as is claimed,
$10 per boiler horsepower, builders' rat-
ing.

For instance, for a 150-horsepower
boiler it would cost SI 500, or more than
the boiler itself. As the writer of the
article did not explain this, I think it
well to do so. At that rate it looks like
a stiff price for a steam blower, and the
system is nothing but a steam blower.
The article says steam can be decom-
posed in cast-iron retorts, but does not
say at what temperature. I claim that
the Cornell system does not dissociate
it, and that if steam is decomposed by
this system the temperature is above the
igniting point of the gases; this being
the case they will ignite back to the
outlets.

Twenty odd years ago I experimented
with a man who claimed that he had a
patent on a method of making these gases,
and in these experiments we melted the
wrought-iron pipe and malleable-iron fit-
tings in the furnace. At the melting
points of these metals the inventor failed
to dissociate the steam. The steam pass-
ing through the Cornell retorts is sim-
ply superheated and is not dissociated
as claimed. I have heard that Doctor
Paget, an Englishman, experimented with
the Cornell system and was unable to
prove dissociation of steam at a tem-
perature of 4500 degrees Fahrenheit, and
was not able to collect any gases re-
sulting from dissociation. Paul J. Dash-
nell, of Johns Hopkins University, and
William C. Day reported that this system
did not dissociate steam.

One who is looking for truth should
read a mechanical engineer's experience
with the system on page 39 of the March
7 issue, and any engineer who is in-
terested in the subject can make any
style of steam blower on the market him-
self and prove to his own or his em-
ployer's satisfaction that the statements
contained in this article are nothing but
truth as found out years ago by prac-
tical running and mechanical engineers.
Michael H. Harrington.

Fall River, Mass.

August 22, 1911

POWER

299

"(1 \\'(-i-kl.v by tlie

Hill Publishing Company

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Contents i

Jlodern English Power Plant

Cost of a Power House

The Ueslgn of Steam Power Plants

Veteran Engineer and Engine.,

A New High-pressure (jaa Blower Set....

Velocity from Heat Energy

Steam Engines and Steam Turbines

I.OSB iMie to Incomplete Combustion

Advantages of Superheated Steam

Sampling and Analysis of Furnace Gas. .

Water Itesources of .Minnesota

A .Magnetonifchanlcal Ammeter

Central Station Service vs. Isolated Plant

Operation

Cutting Out Dynamos In Parallel

What DIspbiced the Bnmh Holder?

Apparatus for Passing (Jas Samples to a

Cnlorlmnler

Well Man.-iged Diesel Engine Plant

Test of a Blast Furnace <Jas Engine

Vnpor l-ock In a Fuel Oil Feed Pipe

The Heavy Oil Engine

Trouble from a Long Exhaust Pipe

PraetlrnI letters:

Ilomemnde Water Ejector. .. Care-
|e«BrieH<< In the Power Plant....
Dnngerotis Water Column Connec-
tion .... Wnnts IMagram Exphilned
... llonieirndn c.imi.fMind Feeder.. ..
Suspending HnrlKonlnl Tubular Boil-
ers by Menns of ILincers Side

• I'Iny In t'rank Pin Pprasses....
Kagi:ed Water Tubes. . . .Scale Cause
of low Vacuum. ... Indicator Cord
F*ock Knot . . . . I>evlce for Separating
I'Islon Rod from Crosshead 2!>2

Discussion f.eti'r« :

Piston nines .... Air Compressor
llunning Under. . Pulling In Crank
Pins. . . . Flllne Englnetrlnir Articles
....fJoIng Over ihe fhlef. Head
. . . . F'erfnrman'-e nl Redondo Plant
....Isolated Plant Management....
The Cornell System 2ftri

Editorial 2f>f>

Ammonia Absorption Refrigerating System

Clear Ice without Relmlling

Protecting Compressor

Air In Ice Water System

2S.S
288

289
200
201
291
291
291

Good Work. Needed on
Piping

Where condensers are used the sup-
ply of cooling water is often brought into
the plant through long pipes laid for the
greater part of their length underground.
Cast-iron pipe with "bell and spigot"
ends made tight by lead and oakum joints
is generally used because the cost of
pipe with this type of joint is much be-
low that of pipe with flanged and bolted
ends. To insure tight work in pipe
joints of this type requires the exercise
of a high grade of skill, and the work
should not be done by ordinary me-
chanics. While under pressure and be-
fore being covered with earth, lead joints
are readily inspected and easily made
tight, but under suction, leakage is not
so apparent, and it may become quite
serious before it is suspected. In cases
when leaks are known to exist it is al-
ways difficult and sometimes impossible
to locate them, particularly if they are
numerous and small.

In surface condensers air in the cir-
culating water will not cause a serious
inconvenience or impairment of the vac-
uum. It may hasten the corrosion of the
tubes by supplying the oxygen neces-
sary for their destruction, but a slight
increase in the speed of the circulating
pump will maintain as high a vacuum
with large quantities of air in the water
as will a lower speed without it. But
with jet or barometric condensers free
air in the water means a reduction in
the vacuum that cannot be corrected by
increased pump speed or a wider open-
ing of the injection valve. In fact, either
of these will make matters worse, for the
degree of vacuum is as easily reduced
by water as by air.

All natural water carries air in sus-
pension, sometimes as much as five per
cent, of its volume. This air is set free
in the lower pressure in the condenser
and when increased by a larger volume
drawn in through leaking joints the dif-
ference between the theoretical vacuum
that should exist at the temperature of
the overflow and the vacuum that actual-
ly does exist is noticc.Tble and annoying.
With a dry-vacuum pump a hich vacuum
may be had by an increase in speed
above that for which the pump was dc-
siencd and the efTccf of the excess air
will be felt only in the inefBcicncy of
the pump, which will be taxed to the
limit of its capacity to maintain a vac-

uum of, say, twenty-six inches, where
twenty-eight or more is desired.

Although reduction, by one pound, of
the back pressure means so much more
for a turbine than for a reciprocating
engine, it is a matter that should not be
neglected even with the latter type of
engine, and when installing a suction
pipe, with any type of joint, this should
be remembered. Only the conscientious
exercise of skill of the highest degree
will insure good results and in this class
of work no part of it can possibly be
too well done if permanently satisfac-
tory operation is desired.

Handicaps of tlie Studious

Young engineers are constantly being
urged to improve their minds and there-
by their stations in life by studying the
principles on which their practice is
based. This advice is excellent. In-
creased knowledge is the one and only
legitimate lever by means of which any
man can lift himself from a lower posi-
tion to a higher one. But when one
thinks of the haphazard methods ex-
emplified by some of the many textbooks,
handbooks, etc., which are alluringly of-
fered to the ambitious skilled worker it
becomes evident that the advice to study
should be accompanied by a warning to
he careful as to the books that are
studied.

To illustrate the kind of misinforma-
tion with which the home student is
menaced: A certain reference book de-
scribes a gasolene engine working on
the two-stroke cycle as a "four-cycle
engine with the four cycles cotnpresscd
into one revolution." Another one states
that in the operation of a boiler furnace
"too tnuch excess air is uneconomical
because if more oxygen is supplied than
the fire can burn, it and its nitrogen take
heat away from the fire up the chimney."
Again: "A pressure is generated in the
wires of an armature by friction due to
the passage of the wires through the
magnetic current." Once ttiore: " The
armature core is split up into thin sheets
to keep the magnetic current from flow-
ing in irregular paths and make it pass
directly across from pole to pole."

The writers of such misleading "ex-
planations" are not to blame; they
honestly think they are helping the
struggling seeker after knowledge. But
Ihe results of their unconscious blunders

300

are just as deplorable as though they
were intentional.

Of course, the ambitious man who
must do his studying at home and prac-
tically alone is unable to discriminate
between accurate information and the
other kind when he first strikes it, but
he can avoid many false leads by merely
asking for advice from the editors of
appropriate engineering journals of rec-
ognized standing. We write scores of
such advisory letters every year.

Single and Double Eccentrics

When both steam and exhaust valves
of a Corliss engine are operated by a
single eccentric, the range of cutoff is
limited to less than one-half the stroke
of the piston, so far as the mechanical
operation of valve release is concerned.
But as there is an element of time that
enters into all of the valve movements
the valve does not close on the instant
that it is released, and indicator diagrams
are often seen in which it is plain that
the cutoff was not fully accomplished
until the piston had made nearly, if not
quite, three-quarters of the stroke.

This is much later than it should oc-
cur in the regular work except in cases
of momentary overload where the aver-
age load is carried with a much shorter
cutoff as, for instance, in the case of
rolling-mill work.

When the valves are set for the latest
possible cutoff the steam valves are given
but little lap, the exhaust valves are
open slightly when the wristplate is in
mid-position, and the eccentric leads the
crank little more than 90 degrees. This
arrangement, while it is the best pos-
sible for the operation of the steam
valves, giving a rapid opening movement,
is not satisfactory for the exhaust valves
as it makes for a late opening and the
steam does not get out of the cylinder
as early as it should.

This condition is remedied by the ad-
dition of a separate or exhaust eccentric
allowing the adjustment of the exhaust
valves independently. The separate ex-
haust eccentric was first applied to Cor-
liss engines for the purpose of getting
an early release with a late cutoff, but
was not used to get an early compres-
sion, for at the time of its adoption it
was customary to carry as little as pos-
sible, the exhaust valve closing just be-
fore the end of the stroke.

Later the independent exhaust ec-
centric was adapted to engines of the
rolling-mill type or where an early open-
ing of the exhaust, as in the case of a
condensing engine, was necessary to get
the benefit of the vacuum early in the
stroke.

Setting the exhaust valves of the
double-eccentric engine is not the com-
plicated operation it at first appears,
though many have balked at it without
attempting to reason out the right course

POWER

to pursue. The exhaust wristplate is se-
cured at midtravel and the rods are ad-
justed to give the valves the same nega-
tive lap that would be given if there
were but one eccentric on the engine.
The piston is moved to the position in
the cylinder where it is desired that
compression shall begin, and the eccentric
is turned on the shaft in the direction
the engine is to run until the edge of
the valve is on a line with the edge of
the port. The eccentric is fastened and
the piston is then moved to the other
end of the cylinder to test the accuracy
of the work.

In many cases, the exhaust eccentric is
nearest the frame and is set before the
other as a matter of convenience. But
whether it is set first or last, it is not a
task from which the engineer should
shrink or feel the least hesitancy in at-
tempting.

Know the Details
To successfully handle a repair job
nothing is more important than a
thorough knowledge of the causes which
made the repair necessary. If a repair
is to be made, a history of the previous
conditions and an analysis of those con-
ditions will, if intelligently applied, often
prevent a recurrence of the need for the
same kind of repair.

At the top of a vertical boiler the
gasket under the steam-outlet pipe olew
out and was replaced, only to fail agnin
as the working pressure was approached.
The operation was repeated twice, with
the same result.

Discouraged by the continued failure
and unable to account for it, the en-
gineer sought the advice of the chief
engineer of a nearby power plant, who
had the reputation of having had few
failures and of seldom erring in judg-
ment in an emergency.

When he arrived he insisted upon hav-
ing the whole story before looking at
the job. He then examined the flange
faces and tested them for accuracy. He
examined the packing that was to be
used and found that so far there was
nothing that appeared to be out of the
ordinary line. The fianges were true
and came together fair; the packing was
of good quality and should make a tight
joint. He next turned his attention to
the stud bolts around the hole in the
boiler head. Upon trying the nuts he
found that three of them would fit three
of the four studs, that one would fit
none of them, and that none of the nuts
would fit on one particular stud. Here
was the cause of the failure. In some
way the threads on the one stud or in
the one nut had been slightly deformed
and in forcing the nut on the stud so
much strength was expended that there
was little left for producing pressure
on the gasket at this point.

By means of a split die held in a pat-
ternmaker's clamp the stud was put in

August 22. 1911

shape, and a tap run through the nut
made that all right. Then the gasket
was put in and the nuts screwed down
solid.

As the temperature rose while get-
ting up steam, the joint was "followed"
by judiciously tightening the nuts, and
when the working pressure was reached
and the engine started everyone was sat-
isfied that the repair was permanent, as
it proved to be.

This incident illustrates two points in
power-plant operation: The necessity
for a thorough knowledge of the de-
tails of the work to be done and the
application of mechanical common sense,
without which the most ordinar>- work is
poorly done and usually unreliable.

"So Easy to Fool 'em"

Whether a central-station contract
agent retains his job or not depends en-
tirely upon how successful he is in se-
curing contracts. Is it any wonder, then,
that he puts much energy and all of the
intelligence he has into his efforts to close
down the isolated plant?

In some localities and under some
conditions central-station service is
actually cheaper than operating an iso-
lated plant. It is our belief, however,
that more isolated plants are closed down
to the ultimate loss of the owner than
otherwise, and, furthermore, that the bulk
of the blame for this state of affairs
rests largely with the isolated-plant en-
gineer himself.

In order to combat the central station
successfully, the isolated-plant engineer
must put as much knowledge and energ\
into the contest as the other fellow does.
That the central-station agent realizes
that he is wasting time in trying to get
an alert and capable isolated-plant en-
gineer's job away from him is demon-
strated by a remark actually made by a
central-station solicitor after calling on
the engineer of the plant in an office
building of moderate size to get data in
regard to the work the plant was doing,
in order that he might make an estimate
to cover a proposal for central-station
service. Discovering that the engineer
had in hand accurate and complete fig-
ures on the cost of the power he was
producing, the solicitor said: "If more
engineers kept track of costs it wouldn't
be so easy for us to fooi 'em." Note
the last five words: "so easy to fool
'em."

There is a valuable lesson for some
of us in that remark. Perhaps a few
isolated-plant engineers will get it and
profit thereby.

Visionary schemes in power-plant
practice may work out all right once in
a while, but it is better to determine
what may reasonably be expected of any
proposed improvement before much
money is spent.

August 22. IP 11

POWER

Bro/ize and Babbitt Phi Bearings

Why do some engines have bronze
•vristpin boxes and babbitted crank-pin
l-oxes^ B. P.

The crank pin turns entirely around
in its box in a revolution, while the
wristpin box simply vibrates through a
few degrees. There is. therefore, much
less friction developed in the crosshead
bearing, and some designers feel that
it is better to use a harder metal there.

IC

Effect of Advanced Eccenti

Will a compound Corliss engine with
a speed of 42 revolutions per minute
race if the eccentric is advanced too
far? (What influence will the eccentric
have on a Corliss engine more than
making the valves act earlier?

L. W.

Advancing the eccentric on a Corliss
engine without altering the lap of the
valves will cause earlier lead and ex-
haust-valve closure, which with a very
light load might make the speed of the
engine irregular but would not cause
overspeed enough to be called racing.

Advantafres of High Piston

Speed

What are the advantages of high as
compared with low piston speed ?

E. W. C.
High piston speed produces a corres-
pondingly greater amount of power with
the same mean effective pressure and
enables one to use a smaller engine for
the same work. The disadvantages are
the difficulties of taking care of the
greater momentum of the moving parts
and of getting the steam, or other work-
ing fluid, in and out of the cylinder in

I the shorter time available.

Moving Eccentric in Settimr

Vahe

Is it always necessary to loosen the
eccentric on the shaft when setting Cor-
liss engine valves?

F. B. C.

It may or may not be necessary in
setting Corliss engine valves to move
the eccentric. Give the valves the proper
lap, with the wristplate at the middle
of its travel without any reference to
the position of the crank or eccentric.
Then turn the engine to the center. If
the lead is correct, the eccentric need
not be moved.

Constant Potential at All Loads

It is desired to preserve a constant
electromotive force at all loads at a point
outside of the station, what kind of a
dynamo should be installed at the sta-
tion? Explain the action of this dyn-
amo.

C. E. N.

A compound-wound dynamo will
maintain approximately constant poten-
tial at any given point in the circuit
by proper adjustment of the compound-
ing. If the system is direct current
and the potential does not need to be
rigidly constant, this type of machine is
preferable. Its regulation is effected
by means of an extra field winding in
series with the armature. As the load
increases, the current in this winding
increases, and that strengthens the field
magnet of the machine and thereby in-
creases the electromotive force gener-
ated in its armature winding sufficiently
to make up the voltage drop in the
armature and line and keep the potential
practically constant at the stated point.

Heat Loss to Ashpit

If the analysis of some bituminous
slack having a heat value of 12,500
B.t.u. per pound is, ash, 10 per cent.;
volatile matter, 37 per cent.; sulphur,
2 per cent., and if the refuse in the ash-
pit has a heat value of 3750 B.t.u. per
pound and an analysis showing, ash, 75
per cent.; volatile matter, 5 per cent.,
and sulphur, 0.5 per cent., what is the
percentage of heat lost to the ashpit?
C. M. R.

One pound of coal, if the combustible
which it contained were completely
burned, would yield 0.1 pound of ash
having no heat value.

According to the data given, however,
all of the combustible in a pound of coal
is not completely burned, and some
fraction of a pound is rejected as ash.

The material rejected as ash must
contain the 0.1 pound of true ash as
found by the analysis of the coal itself.

and enough fixed carbon and volatile
matter to yield 3750 B.t.u. per whole
pound of the assumed ash. As, by an-
alysis, 75 per cent, of this assumed ash
is true ash, and as it has been shown
that each pound of coal contains 0.1
pound of true ash, the entire amount of
assumed ash must weigh

If a whole pound of this assumed ash
has a heat value of 3750 B.t.u., then
0.133 pound has a heat value of
3750 X 0.133 = 500 B.i.u.

Then, for each pound of coal fired
500 B.t.u. are lost, due to the unburned
combustible in the assumed ash *ound
in the ashpit. This loss expressed in
percentage is

^= 0.04 ^ 4 per cent.

Donbh- Eccentric Vahe Setting

I would like very much to have in-
structions for setting the valves and
eccentrics on a double eccentric Corliss
engine.

D. E. C.

With the wristplate in the middle of
its travel, give the valves the proper lap.
With the engine on the center turn the
steam eccentric until the steam valves
have the proper lead; 1/32 inch for an
18-inch to ' j inch for a 72-inch cylinder.

Place the piston at that point in the
travel where it is desired that compres-
sion shall begin, and turn the exhaust
eccentric ahead until the exhaust-valve
edge is on a line with the edge of the
port.

Pouer to D/aic I sad up a Grade

.A grade 1000 feet long has a rise of
.50 feet. What horsepower is required
to draw a load of 200,000 pounds to the
top in one minute, assuming the fric-
tion to be 2 per cent.?

D. L. G.

Two per cent, of 200,000 is 4000 which
added to the load gives 204,000 pounds
to be raised 50 feet. To lift 204,000
pounds .50 feet requires the expenditure
of
304,000 ,50 10,200,000 foot-pounds.

A horsepower is equivalent to 33,000
foot-pounds of work per minute. If the
10,200,000 pounds of work is done in one
minute, it will take

IO,200,OfX1 ,

^=^ xcnoQ none bower

POWER

August 22, 1911

Aniiiioriia Absorption Re-
frigerating S}stem
By Fred Ophuls

Of all the plants usually placed in
charge of stationary engineers, those
that are equipped with the ammonia-ab-
sorption refrigerating machines have
given the most concern. There are com-
paratively few engineers who can suc-
cessfully handle this system, not be-
cause the machines and apparatus neces-
sary for its proper operation arp par-
ticularly delicate, or have to perform
functions unlike those generally per-
formed by machinery in other kinds of
power plants, but because the mode of
operation of this system is very dif-
ferent from that of the usual run of
power plants, both chemical and me-
chanical changes being involved. While
there can be found hundreds of engi-
neers able to handle the ammonia-com-
pression system, very few are compe-
tent to operate the ammonia-absorption
system, merely because the latter is not
as well understood.

It is the purpose of this series of arti-
cles to present to the operating engineer
a simple explanation of the mode of
operation of the ammonia-absorption
refrigerating machines, and to show
later, by actual results obtained from a
modern installation of this kind, how
the functions of the various machines
and apparatus making up this system
are related to each other. Besides this.
a discussion will be given bearing on
the use of both the compression and
absorption systems of refrigeration for
purposes where the latter has hereto-
fore been considered best adapted.

The function of a refrigerating sys-
tem is to remove heat and maintain
temperatures lower than those of the at-
mosphere; whether it be to freeze water,
cool rooms for preserving in them per
ishable goods, or for whatever other
purpose. Heat is not a tangible sub-
stance like water: that is, it cannot be
removed directly from one place to the
other, but it must be absorbed by some
medium which can then be removed
from the refrigerator. The medium
which is used to absorb the heat is
called "the refrigerating medium," and
as heat can only be made to flow from
a body at a higher temperature to an-
other at a lower temperature, it is neces-
sar>' that the temperature of the refrig-
erating medium be lower than that at
which ice will form, or be lower than the

Principles
and operation of
ice making and re-
frigerating plant-
and machiner\

temperature to which it is desired to cool
the perishable goods and that of the room
in which they are to be stored. The re-
frigerating medium simply acts as a
sponge to absorb the heat, after which
it is removed and subjected to an opera-
tion by which the heat it has absorbed
can be discarded.

The choice of a suitable refrigerating
medium was a difficult one; but after
many laborious experiments several sub-
stances were found suitable for this
purpose. Among these anhydrous am-
monia is the one most commonly used,
and among the reasons for its choice are
that it can be readily manufactured as
a byproduct of another manufacturing
process and at a price which is not pro-
hibitive.

Anhydrous ammonia at ordinary tem-
peratures and under atmospheric pres-
sure exists in the gaseous form, but
when it is subjected to a certain higher
pressure, it can be liquefied when cooled
to ordinary atmospheric temperatures.
If. from the liquid so obtained part of
the pressure is removed, it will again
vaporize if sufficient heat be supplied
to it and the temperature at which it
will vaporize will be that at which the
liquid boils at the lower pressure.

The property which all liquefiable
gases or vapors have in common is that
when in the liquid form their boiling
point increases with the pressure under
which they are maintained. A familiar
example of this property can be found
in the formation of steam from water.
The latter, when heated under atmos-
pheric pressure, boils at 212 degrees
Fahrenheit. When heated in a closed
vessel, however, and only part of the
steam generated is allowed to escape,
the pressure in the vessel is raised, and
the boiling point will be raised; that is,
the temperature of the water is raised
above 212 degrees Fahrenheit before
boiling will begin. For instance, at a
pressure of 100 pounds per square inch
gage, water will boil at about 338 de-
grees Fahrenheit.

Liquid anhydrous ammonia, however,
boils at very much lower temperatures'
than water under the same pressures.
Under atmospheric pressure liquid an-
hydrous ammonia boils at about 28

degrees Fahrenheit, and under a pres-
sure of 100 pounds per square inch
gage it boils at 63 degrees Fahrenheit.
Furthermore, when a liquid is boiled
and changes its state from a liquid to
a vapor, it absorbs a large amount of
heat called "latent heat," and the latent
heat of liquid anhydrous ammonia at
low temperatures is made use of in re-
frigerating apparatus to absorb heat in
order to produce cold.

Liquid anhydrous ammonia is com-
mercially sold in iron drums in *i'hich
it is contained under a pressure varying
between 120 and 200 pounds gage, the
pressure in the drum depending on the
temperature of the liquid in it. This
liquid is charged into the refrigerating
system and brought into contact with
the substance to be cooled or frozen
under a pressure sufficiently low that its
boiling point is lower than the tempera-
ture at which the substance is to be
maintained.

The liquid or refrigerating medium
will be vaporized by the heat flowing into
it from the substance and the vapor
formed could then be discharged into
the open air. Such a refrigerating sys-
tem would not require complicated ma-
chinery for its operation, but would be
impractical and very expensive to use
on account of the large amount of an-
hydrous ammonia that would have to
be purchased. Furthermore, ammonia
vapors will cause death when inhaled

T.\BUE 1. .SOME PROPERTIES OF LIQriD

.\XHYDROCS .\MMONI.\

1 .1

Pressure on liquid
in pounds per
square inch gage.
2.35
2. .SO
5.24
6.29
136 75
142. OS
144 SO
147 ,56

Ck>rre3ponding
boiling points of
liquid, in degrees
Fahrenheit

— 23

— 22

— 17
— 15

+ 79
+ S1
+ S2
-^s.■^

therefore can-
the open air.

in large quantities, and
not be discharged into
For these and other sufficient reasons
it was found necessary to devise some
means by which the ammonia vapor
could be deprived again of the heat it
had absorbed in the refrigerator and be
reliquefied.

Table 1 gives some properties of
liquid anhydrous ammonia. The figures
in the first column are the gage pres-

August 22, 1911

POWER

303

sures in pounds per square inch under
which the liquid will boil at the temper-
atures given in the second column.
These figures indicate the method that
must be pursued to liquefy the ammonia
vapor and abstract from it the heat ab-
sorbed in the refrigerator.

For instance, if the liquid anhydrous

TABLE 2. SOLUBILITY OF G.\.SES AND
VAPORS IN WATER AT .\TMOSPHERIC
PRESSURE AND VARIOUS
TEMPER.\TUr.ES

\ oliimes of gas,
dissolved by one _
volume of water

Ammonia

Sulphur dioxide.
Carbon dio.\ide. .

Fahrenheit

;i2.8l7Z7.1\XA.O

56.61 47.31 39.4

1.21 1.0 0.9

ammonia is allowed to flow from the iron
drums in which it was bought, into the
cooling or freezing coils under a pres-
sure of 2.35 pounds, it will absorb heat
and boil at a temperature of — 23 de-
grees Fahrenheit. The vapor formed
must be drawn from the coils in order to
maintain the desired low pressure in
them; it can then be compressed to a
suitable pressure, say, 136.75 pounds
per square inch gage. The table shows
that at this higher pressure liquid an-
hydrous ammonia boils at 79 degrees
Fahrenheit. Provided there is cooling
water available at from 54 to 70 degrees
Fahrenheit, the compressed vapor can
be cooled to 79 degrees and liquefied
at this temperature, the point of lique-
fication for any fluid being the same as
its boiling point under the same pres-
sure. Having reliquefied the ammonia
vapor the liquid formed can be used
again for cooling and freezing purposes,
the cooling water carrying off the heat
absorbed in the refrigerator.

There are various ways of drawing
the ammonia vapors from the cooling
coils and compressing them to a higher
pressure. In the absorption machine
these two steps are accomplished by the
use of water.

TTie figures in Table 2 show that water
will absorb ammonia in greater volumes
than it will either sulphur or carbon
dioxide. They further show that the
volume of each gas or vapor absorbed
decreases as the temperature increases,
and if a saturated solution at S?. de-
grees is heated to, say, 70 degrees,
part of the gas or vapor will be again
given off from the solution.

Therefore, the ammonia vapor can be
drawn from the refrigerator coils by
connecting them with a vessel, called
the absorber, containing cold water or
a weak solution of ammonia in water,
called weak ammonia liquor. The weak
liquor will absorb the ammonia vapors
readily until a saturated solution is ob-
tained at the temperature and pressure
of the absorber when the absorption
stops. The saturated solution or strong

liquor is then pumped from the absorber
and discharged into a tank, called the
generator, in which a pressure at least
equal to that required for liquefying the
ammonia vapors is maintained. In the
generator the strong liquor is heated
and part of the ammonia is driven off
and discharged into a vessel called the
ammonia condenser, in which the am-
monia vapor is liquefied by the action
"of cooling water sprayed over or circu-
lated through it.

The removal and discarding of the heat
can be likened to the removal of water
from a basin without a drain, to a
basin at a higher level but with a drain,
by means of a sponge. The dry sponge,
brought into contact with the water in
the lower basin, will absorb part of it,
similar to the flow of heat from the
refrigerator into the refrigerating med-
ium. The saturated sponge is then lifted
to the higher basin and is compressed
so that the water is discharged from it
and can run to waste. The sponge, hav-
ing been compressed and the water dis-
charged from I it, can be brought to the
lower basin again and is ready to ab-
sorb more water. The refrigerating
medium, being deprived of the heat it
had absorbed and reliquefied, can be
reduced in pressure so that it can ab-
sorb more heat. In the case of the
water, the level to which it is raised is
measured in a certain number of feet,
whereas in the case of the heat the level
tn which it is raised is measured in so
many degrees of temperature.

CORRESPONDENCE

Clear Ice without Reboiling

A short time ago I was conducted
through a can-ice plant and was surprised
to find that there were no steam coils in
the skimmer and reboiler. I told the
chief engineer that he surely could not
expect to produce crystal ice without re-
boiling the condensed water, but he re-
plied that they have been doing this all
along, although it was violating the
primary principle of the can-ice system.
He admitted that during the recent hot
weather, while the plant was being
pushed beyond its capacity, with the
temperature of the brine tank at about
10 degrees Fahrenheit, the ice was
slightly cloudy, but still transparant
enough to be marketable without the
slightest trouble. At other times, how-
ever, when it is possible to keep the
temperature of the brine tank at about
16 degrees Fahrenheit, giving the ice 50
hours or more to freeze, it is as clear
as any.

I asked him if there was a story to
tell in connection with the removal of
the steam coils from the reboiler. He
said there was, and related the follow-
ing:

When the plant was erected, the build-
ers estimated that there would be a

shortage of condensed water amounting
to 15 or 20 per cent. To overcome this
they connected a water pipe to the ex-
haust reheater, thinking that by mingling
the water thus admitted with the ex-
haust and passing it through the con-
denser and reboiler, the necessity of
using live steam to make up for the
shortage would be eliminated. But the
results were disappointing. The ice had
a very muddy appearance with a large
red core to it. At first they tried to over-
come this by employing various filtering
devices, but without avail; the color of
the ice remained the same. Then the
water from the exhaust reheater was
shut off and while this improved condi-
tions to a certain extent, the color of
the ice was still muddy and red enough
to be unmarketable. Then came some
more filtering devices, but all of them
failed. Finally in desperation they shut
off the steam on the reboiler. The re-
sult was clear ice and they have not had
trouble since.

Upon further inquiry, however, I found
that the water supplied to the plant con-
tained considerable iron and other in-
gredients which were responsible for the
muddy and red appearance of the ice,
but which condition was overcome by
cutting out the reboiler entirely.

Victor Bonn.

New York City.

Protecting Compre.ssor

In the city of Boston a few months
ago a chief engineer in one of the
breweries was killed by the blowing up
of a compressor. He had been chief
engineer for the brewery for 25 years
and would never allow a man to start
the compressor for fear he would forgot
to open the discharge valve; but careful
as he was, he finally got caught him-
self.

Fir,. 1. Safety Valve between Suction

AND DlPCHARCE

Fig. I gives my idea of a remedy. The
full lines show the original connections
of the compressor and the dotted lines
the modifications. In the piping between
the suction and discharge valve a safety
valve is connected and set tn a desired
pressure, presumably about 300 or 3.S0
pounds. When the pressure builds up
too high the safely valve will let go and

304

POWER

August 22, 1911

discharge the ammonia into the suction
side of the compressor.

Fig. 2 is a sketch of a wrinkle that we
use in our plant to prevent starting up
the compressor with the discharge valve
closed. The rule is not to start a ma-
chine unless the telltale is hanging on
the stem of the discharge valve, which
it can only do when it is open. If it can-
not be put on it means that the valve is
closed.

It consists of a flat piece of tin the
upper part of which is so twisted that

Fig. 2. Telltale Hanging on Valve
Stem

in hanging it on the valve stem the body
of the tin will face the engineer. The
telltale should be painted white and
bright red so as to attract attention.
Edgar G. Schindler.
Roxbury, Mass.

Air in Ice Water System

The milky appearance of ice about
which Charles J. Johnson wrote in the
issue of June 13, is undoubtedly caused
by air and impurities in the circulating
water. It may be similar to Lake Erie
water. In Cleveland, O., for instance,
some of the city water is pumped
through a 9- foot tube from an intake
five miles out in the lake. There the
pumping is not responsible for the milky
condition, because water taken from the
lake direct has the same appearance.
If left standing for about 15 seconds it
becomes quite clear. 1 doubt very much
if the pemedies proposed — an air trap
on the supply line to the pump, or a
pipe direct down from the supply tank
on the roof, or both — will bring the de-
sired relief.

A certain amount of air is always in-
troduced with the fresh water, but the
greater part is admitted whenever the
piping is drained. The stale water
throughout the system ought to be com-
pletely run to waste at least once a week,
or oftener if necessary, but to do so re-
quires air to be admitted by a vent for
the- purpose of breaking the vacuum.
On Mr. Johnson's sketch no vent can
be detected, which would imply that
he does not change the water. Of
course, the stale water becomes mixed
with the remaining cold water and ulti-
mately finds its way to the faucets, the
issuing liquid being milky in appear-
ance. A cloth disk filter (made by the

International Filter Company, of Chi-
cago) in the ffesh-supply line, cleaned
often enough, and a frequent draining
of the system would improve the ap-
pearance and wholesomeness of the
drinking water.

After the system has been drained it
is full of air. If now a vent pipe, not
smaller than I inch, is connected to the
highest point of the circulating pipes,
the new water can force the air out
ahead of it. To prevent the water from
escaping, the vent pipe must extend up
to the highest level, in fact a few feet
more; and preferably be protected
against rain, dirt, heat and frost. .\
'..-inch valve on top of the closed cool-
tank, to help let the air out, would also
be an advantage.

A vent having been provided, the ex-
pulsion of air from the system will fur-
ther be favored by simply discharging
the cold water through the present Ul-
inch return pipe of the pump, in this
way circulating in a direction opposite
to that now used. In other words, feed
the water upward through the eighteen
•'4-inch risers of the building, this being
the direction in which the air moves
naturally. This method ought to be so
eftective that the air will easily escape
and thus make the installation of a
cumbersome tank and other changes un-
necessary.

The centrifugal pump used at present
is, in Mr. Ophijls' opinion (June 27 is-
sue), the chief reason for the milky
appearance of the water; it being sup-
posed that this pump divides the air so
finely that it would not rise from the
water unless a large disengaging sur-
face is provided. It may be that the
churning action of this pump does con-
tribute to the evil more than a slow-
speed piston pump would, but I believe
in making this expensive change only
after everything else has been tried.
Triplex plunger pumps are frequently
used in connection with unbalanced cir-
culating systems, being better adapted
for high heads than common centrifu-
gal pumps, but they are. more expensive
and noisy.

Perhaps the pump is being driven
faster than necessary. The actual con-
sumption is certainly not in excess of
4 gallons per minute. If, to prevent a
greater rise in temperature and to elim-
inate excessive waste of the water first
diawn from the faucet, six times as much
water is circulated, this would mean 24
gallons per minute as the flow capacity
of the svsteni, at which rate the friction
per 100 feet of l':^-inch pipe would be
only 2.fi pounds. The water leaving the
cooling tank at, say, 43 degrees Fahren-
heit must not come back colder than 53
degrees, which temperature physicians
prescribe as being proper for quenching
thirst. If the water returns at. sav, 50
degrees, the speed of the pump can be
reduced.

For the maintaining of uniform tem-
peratures it is bettei to depend on regu-
lating the refrigeration produced, than to
simply alter the rate of flow by means
of a bypass around the pump. Also, the
regulating valves at the top and the bot-
tom of the risers should be left wide
open. If. owing to the greater pressure
prevailing, the water issues with too
much force from the faucets on the lower
floors, their effective opening can be
plugged dcwn to 1/16 inch diameter if
necessary. Why there should be v_,-inch
globe valves used on the '-4 -inch outlet
pipes, as shown in the sketch on page
934, is not apparent.

When the foregoing has been tried, and
no satisfactory results have been ob-
tained, recourse may be had to the large
tank recommended by Mr. Ophiils, al-
though many plants are operating satis-
factorily without it. The connection of
the 2-inch horizontal run at the top with
the 2-inch riser will have to be cut off.
For upward circulation through the eigh-
teen >4-inch pipes the 2-inch riser can
then be continued up to the bottom of
the feed tank, and a 2-inch pipe carried
direct from the horizontal run to the tank,
entering just below the water level, pre-
ferably at a tangent. For downward cir-
culation, the 2-inch riser would have to
bt continued to the top inlet of the tank,
and the outlet connected with the 2-inch
horizontal run or header.

In neither case does the use of the
open tank permit the fresh supply to be
taken into the system at the basement as
at present, because of lack of suitable
control. The cheapest way is to convey
the water direct from the roof tank
through a .14-inch pipe to the balancing
tank, the outlet being fitted with a float
valve to keep the water level constant.
Under the feeble pressure available up
there, it will he difficult to use an ordi-
nary filter successfully. A separate feed
line from the basement to the balancing
tank on the top floor would permit the
use of a pressure filter in the basement.

This arrangement will still act as a
balanced system, except that the head
will be increased by the elevation of the
de-aerating balancing tank, but with no
appreciable effect on the power required
by the pump. .■Xs to the size of this gal-
vanized tank, it should not be more than
3 feet in diameter and 3 feet high, which
would be big enough to easily hold 120
gallons, the equivalent of five minutes'
pumping. The bottom and sides of the
tank should be well insulated, and the
open top protected, in addition to provid-
ing an overflow pipe and drain.

Charles H. Herter.

New York City.

By the control and development of
its water powers, Tennessee hopes to
largely increase its revenue and give
employment to an additional million
people.

August 22. 1911

P O ^' E R

305

wPo^

Toltz Superheater

In construction this superheater con-
sists of seamless drawn-steel tubes ex-
panded into steel headers^ Fig. 1 shows
a general form designecMp- installation
in a horizontal type of warer-tube boiler.
The headers are placed alongside the
boiler drums, away from the heat of the
furnace, and the tubes extend down in-
to the setting, across and under the drums
in the first gas pass, where they are sub-
jected to the heat.

The tubes are round at the ends so
that they may be properly expanded into
the headers and at the bends. They
may, therefore, expand in the heat of
the gases without injury or change of
shape. In the run, the tubes are flattened
so as to get the steam into a thin sheet,
thus thoroughly superheating it. It is
claimed that this construction enables
the heat to easily reach the body of the
steam and distribute the temperature
uniformly throughout its mass.

Fig. 2 shows the Toltz superheater as
installed in connection with a horizontal,

fy/23t the in-
ventor and the manu
fjcturer are doing to save
time and money in the en-
0ne room and power
house. Engine room
news

return-tubular boiler. The headers in
this case are above the combustion cham-
ber, where they are not subjected to
the heat of the gases. The superheating
elements consist of a U-section of seam-
less drawn tubes. Application of this
superheater to other types of boilers is
made by employing either horizontal or
vert'cal superheating elements, always
retaining the feature of outside headers.

Fig. 2. Superheater Installed in Reti'rn-tubular Boiler

The Toltz superheater prevents the
superheat from becoming too high by the
use of a bypass controlled by a thermo-
static valve so that saturated steam may
be admitted to the superheater. It is
claimed that the temperature of the
superheated steam can be maintained
within 8 per cent, of the maximum super-
heat for which the apparatus is set.

The Toltz superheater is being placed
on the market by the Power Improvement
Company, 510 Enterprise building, Mil-
waukee, Wis.

Fir,. 1 Tf'i T/ ^1 iFRHEATER Designed FOR Hori7ontal Water-tube Boiler

Clas,s 'P B" Duplex Power
Driven Air C'()inpre,s,sor

This compressor is of the familiar
duplex type wiih the air cylinder coupled
to the frame and a central drivint wheel.
It is of the latest design in power-driven
air cotipiessors. an-i is ot inclosed, dus.-
pronf construciion with automatic flood
UibricTfion for the m.T'r '>earings, crank
pins and crosshcads. These compressors
.ilso have increasd wearing surfaces,
large valve areas and grcnier intercoolcr
surface.

Thj principal n-,.>v features are the
"vater separator and the clearance con-
troller.

Details of the water separator arc
thown in Fig. I. It cf.nrirts of a large
water 'cparator or iin-sturc trap which

306

POWER

August 22, 1911

is placed on the discharge pipe of the
intercooler, through wliich all air after
cooling must pass. It is made with two
concentric cylindera, with two overlap-
ping lips, between which the air passes.
Entrained moisture is csught on the sur-
fr.ce of the inner cylinder and project-
ing lips and drains to the chamber in
the bottom of ihe separator, from w-hicn
it is removed through a drain cock. This
device results in the delivery of prac-
tically dry air to the high-pressure cyl-
inder.

The automatic clearance controller,
shown in Fig. 2, is a device for eco-
nomically regulating the capacity of the
compressors by van'ing the amount of
clearance. It consists of a number of
clearance pockets which are thrown au-
tomatically into communication with the
ends of each air cylinoer in proper suc-
cession, this process being controlled by
a predetermined variation in the receiver
pressure. Regulation is obtained in five
stages, namely, full load, three-quarter
load, half load, quarter load and no load.

The operation of this system of regu-
lation is as follows: With the com-
pressor operating at paitial capacity, a
portion of the air is compressed into an
added clearance space instead of pass-

FiG. 2. Automatic Clearance Controller

ing through the discharge valves. This
air expands on the return stroke, giving
up its stored energv to the piston. The
inlet valves remain closed until the cyl-
inder pressure equals the intake pres-
sure, and then open automatically by a
slight difference of pressure; free air is
admitted to the cylinder for the re-

FiG. 1. Sectional View of the Water Separator

mainder of the return stroke. The inlet
capacity of the compressor is thus re-^
duced without reducing the intake pres-
sure.

On a two-stage compiessor, clearance
space in the proper proportion is added
simultaneously to both high- and low-
pressure cylinders, thus maintaining a
constant ratio of compression throughout
the entire load range and obtaining the
highest compression efficiency. The re-
duction in power secured with this meth-
od oi" control is practically in direct pro-
portion to the reduction of load. This
regulator is simple in construction and
entirely automatic in operation.

The compressors on which these de-
vices are used arp made by the Inger-
soll-Rand Company 11 Broadway, New
York Citv.

Peat Society Convention

The annual convention of the Ameri-
can Peat Society will be held this year
at Kalamazoo, Mich., on September 21,
22 and 23. The arrangements are in the
hands of the executive committee which
has laid out a large and attractive pro-
gram. Among the papers to be read
-are the following: "The Peat Gas Pro-
ducer of the Department of Mines,
Canada," by B. F. Haanel; "Latest De-
velopment in Gas Producers," Professor
Fernald; "Peat Dredging," Messrs. Bul-
ask and Garnett; "Powdered Peat for
Power," Doctor MacWilliam; "Peat Ex-
cavators," L. B. Lincoln; "Recent De-
velopments of Peat as a Power Factor,"
Doctor Mighill; "Drainage of Peat De-
posits," Doctor Pratt; "The Canadian
Government Peat Fuel Plant." A. .■Xnrep,
Jr., and a paper by Dr. N. Caro, the
subject of which will be announced later.
It is expected that GifFord Pinchot
will be present and deliver an address.

For particulars inquiry should be made
to Julius BordoUo, Kingsbridge, New
York City.

August 22. 1911

POWER

307

Universal Craftsmen's Con-
vention

The ninth annual convention of the
Universal Craftsmen Council of Engi-
neers was held in Philadelphia, Penn.,
August 8 to 11. The Majestic hotel was
the headquarters, and the business ses-
sions of the convention were held be-
hind closed doors in the main banquet
hall. The Parisienne cafe of the hotel
was tastefully arranged by the supply-
men for their exhibit.

On .Monday evening at seven o'clock,
Charles A. Hopper, chairman of the
committee of supplymen, introduced
Grand Worthy Chief John Cope, who
formally opened the e,\hibit in an ap-
propriate speech.

On Tuesday morning at ten o'clock

and dances; Frank Corbett, Consolidated
Safety Valve Company, tenor solos; Jim
Devins, Peerless Rubber Manufacturing
Company, monologue; Monroe Silver,
parodies; Billy Murray, Jenkins Broth-
ers, uptodate ditties; Jack Armour, of
Power, songs and stories. Frank Mar-
tin, of Jenkins Brothers, was the master
of ceremonies.

After the performance the delegates
were entertained by the supplymen in
the main dining room.

At the closing session on Thursday
afternoon the following grand officers
were elected :

John Cope, past worthy chief, Cleve-
land, O.; Thomas H. Jones, worthy chief,
Washington, D. C. ; James U. Bunce,
assistant worthy chief, Buffalo, N. Y. ;
Henry C. Senn, secretary, Batavia, N. Y. ;

the Lagonda Manufacturing Company,
Watson & McDaniel Company, McLeod
& Henry Company, Souiliern Engineer,
O. F. Zurn Company, E. J. Rooksby
Company.

SOCIETY NOTES

On August 17, J. N. Mulder, of Am-
sterdam, Holland, presented an interest-
ing paper on "Some Types of Internal
Combustion and Steam Engines" before
the American Society of Engineer Drafts-
men at the Engineering Societies build-
ing. New York City. On June 18, 1911,
this society had been in existence for
one year, and now has a large member-
ship, extending over the entire country.
To become a member a man must pass
riRid rcqiiircnicnts which certify to his

^t y^i *f:» Jf."

I^K^pbL^S4 jJKr- M^'Iwvh^Ii ' ^^^^

m

^^

1

■^^^"—"•^•^^^^^H^^BIH^^^^HPBiHWi

^ III

^ ■■"* p-.,..

the delegates and guests assembled in
the main hall of the Majestic hotel for
the preliminary proceedings of the con-
vention.

Thomas O. Organ, chairman of the
convention committee, introduced the
Rev. Charles H. Bond, who offered the
invocation.

The address of welcome was made by
Samuel W. Wray, private secretary to
the Grand Master of Masons of Penn-
sylvania. He was responded to by Grand
Worthy Chief John Cope.

Addresses were also made by the Hon.
Robert Bringhurst, ex-city treasurer, and
Past Grand Chiefs W. S. Cadwell and
Robert J. Ingleson.

The features of entertainment included
visits to Independence hall. Masonic
Temple. Fairmont park and Willow grove.

On Wednesday evening an entertain-
ment was given under the auspices of
the supplymen, comprising the follow-
ing enjoyable numbers: Joe McKenna,
popular songs; Johnny Forsman. songs

UiNl\ |-K,-AI. CkAh i^M|■.N A I Ph i LAUKLFH lA

Nelson J. Burdick, treasurer, Chicago,
III.; P. H. Early, chaplain, Milwaukee,
Wis.; William Armstrong, warden, New
York, N. Y.; William Wyklen, guard,
Chicago, III. Charles Siegrist, Cleve-
land, O.; H. E. Terry. Toronto, Ont.,
and Henry Klug, Tacoma, Wash., were
chosen as trustees.

It was voted to hold the next annual
meeting in St. Louis, Mo.

The following firms had exhibits: V. D.
Anderson & Co.. John R. Livezey, Power,
Jenkins Brothers, Dearborn Drug and
Chemical Works, Ouaker City Rubber
Company, Greene, Tweed & Co., Lunken-
heimcr Company, W. B. McVicker Com-
pany, the C. R. Squires Company, the
Elliott Company, the Anchor Packing
Company, American Steam Pump Com-
pany. France Packing Company, Stand-
ard Manufacturing and Supply Company,
Keystone Lubricating Company, the Gar-
lock Packing Company, the Cyrus Borg-
ner Company. Under-Feed Stoker Com-
pany of America, A. B. Botfleld & Co.,

competency as an engineer draftsman,
and this feature is attracting the atten-
tion of employers who have come to
look upon the society as a medium
through which to secure men whom they
can depend upon. A plan has been
inaugurated whereby those, who through
any good reason are not in a position to
join as a member, may become associated
with the organization for a limited time
as an atfiliatc member. An affiliate does
not enjoy the same privileges as a mem-
ber, and is not entitled to vote at the
meetings.

PERSONAL

Harry H. Pratt has severed his connec-
tions with the Du Bois Iron Works, Du
Bois, Penn., having for the last four
years been manager of the firm's Buffalo
office, and has entered into business for
himself. Mr. Pratt will be pleased to
hear from manufacturers who desire
representation in western New York.

308

POWER

August 22. 1911

11 r e r
and general manager of the American »Steam
Gauge and \'alve Manufacturing Comj^any.

He has accomplished things since he
undertook the management of that concern
which are noteworthy.

Mr. Phillips has always been a great believer
in advertising. In other words he has great
faith in it —and because of this and his judg-
ment in mediums and follow-uj) he has made
it pay.

He takes the broad view that to make
advertising pay he must get an initial distri-
bution of his goods through advertising and
the repeat orders will take care of the selling
expense.

So, of course, the first requisite is reliable
])roducts, and the second a selling organiza-
tion of good men and advertising that is
advertising.

Now, Mr. Phillips is going even farther,
and occasionally devoting his space to an
educational campaign to show and prove
that engineers who are ambitious to get
above the level will take the initiative and
■put things" up to headquarters.

Here is what he has written us about it,
and because there is sound sense in the doc-
trine we print it here.

Ad. Editor Power,

New York.
Dear Sir:-

I personally believe it would be vers- advantageous
for your advertisers as a whole if more of the full
jxige advertisements occasionally contained copy simi-
lar to some which we have recently prepared showing
the 1 eed for the engineer to go to headquarters and
ask .'or the necessary power plant devices to nm
his engine room properly

If quite a number of yiair full i)age advertisers do
this, I am sure that the result will be generally bene-
ficial to both readers and advertisers, and a con-

certed effort on the part of the ad-
vertisers and the editoria' staff to
show the engineer the necessity for
doing this will certainly benefit
everv- one. I hope you will find
it advisable to take this matter
up with some of your advertisers
for whom y'(ju are doing work, and
you can be assured of our hearty
co-operation at all times. How can
the advertiser expect to benefit

unless he first shows the jjurchaser a way to benefit

himself? Yours very truly,

American vSte.^m G.\uge & \'-\lve Mfg. Co.,
Ralph B. Phillips,

Treasurer and Gen. Mgr.

You mav" remember the story of the engi-
neer who knew a lot about power plant engi-
neering practice. He was a careful reader of
the reading columns and advertising pages of
his paper. He kept catalog files and interest-
ing information and figttres onplantequipment.

That was his trouble — he kept them.

One day the manager said to him : " Here's
something new that looks pretty good to
me, what do you know about it?"

"Why 1 know a lot about it," replied the
engineer. "Only last night I was telling
mv wife how we could make good use of
that here."

"Telling vour wife I" exclaimed Mr. Man-
ager. " What in blazes has she got to do
with it? She doesn't run this plant. Why
don't vou come to me? I don't want to
run a back-number plant and I'm depending
on you as the ])ower sj^ecialist to keep me
informed. "

The engineer went back to the engine-
room with a new idea. He sat on it long
enough to hatch out something that's been
with him ever since — to his everlasting bene-
fit. He has learned that knowledge without
actioti is like a motor boat without gasolene —
voti don't get there.

He has also learned that he can suggest
things to the management without being
acctised of "btitting in."

Likewise he's gained
his own job.

When a man gets in that position he has
so lived that he can look anybody in the
eyes and tell him to "go to."

a new respect for

^t^

V.

NIA\" YORK, Al'GUST 2^^, 1^11

No. 9

THE engineer who takes charge of a power plant
such as is found in many of the large office build-
ings, must possess some of the qualifications of a
business man, in addition to those of a first-class
mechanic.

The successful engineer usually has spent his younger
days in machine-shop or millwright work, in addition
to an apprenticeship as fireman or oiler, and has later
supplemented this with more or less technical study.
By the time he has gone through the various stages
he has probably spent at least ten years of hard work
and at last finds himself in charge of a plant.

Here he is confronted with problems of a different
nature and begins to realize that the cost of operating
the plant and the results obtained for every dollar
sf)ent is the standard from which the owner judges
his worth and ability.

One man may take charge of a plant which is in
good condition and run it until it cannot be run any
longer excej)t at a great loss; another will take charge
of the same plant, run it, and maintain it in first-
class condition regardless of expense; but the real
engineer will maintain and keep ever^'thing in first-
class condition at a minimum cost. This requires busi-
ness ability as well as mechanical skill.

Careless handling of supplies and slipshod methods
' Men incur a useless expense equal to the chief's salary'.

Ask yourself the following questions and the an-
wers will indicate to which ty|)e ol engineer yon belong :

I>o yfiu know how much waste should be uM'd in
your plant ever)- day, and how much is thrown aside
through indifference on the part of the men?

How much packing is spoiled by lying arountl the
'■ngine rw>ni, or do ymj give out just enoutrh and
' ep the rest locked up?

How much oil at y> cents a galkm dm's yotir oiler
waste ever)' day?

As chief engineer, do you know i^rom personal obser-
vation that your boilers are clean or do you take the
fireman's word for it?

How many traps are blowing steam and how much
water is being lost through improperly packed pump
rods? Or, what percentage of the water handled is
lost through leaky suction and discharge valves?

Is the slide valve of your engine tight? When did
}ou examine it last and in what condition did )'ou
find it?

Have you any idea as to how much steam per horse-
power-hour your engine should take; and having that
knowledge what means did you take to ascertain if
the engine was exceeding this amount?

Arc your grates in good condition or are tlicv full
(if holes and waste coal?

Do not poor grates, poor fire tools and an indiflVrcnt
chief soon make the best of firemen lose interest in
their work?

Another ])r(>lilic source of waste that few engineers
take into consideration is what might be termed
"tinker jobs." These often take up more time and
material than the article mended is worth. As an
instance of this, not long ago, an oiler was found
indii.striously trying to solder the bottom of an old
sfiuirt can which, when new, cost about 25 cents.
The soldering irons were heated by a gas furnace
which had been buniing for more than ,-^o minutes.
The cost of this gas added to that of the solder and
the man's time amounted tf) more than the price < f
a new can.

Although the operating force should be able to
make all ordinary repairs in a medium-sized ])lant, the
line should be drawn between repairs and tinker work.

Here is where the business part of the chief's worl:
comes in. He should suixrvise, criticise and exert
constant vigilance; that is the price of success.

310

POWER

August 29, 1911

The Cincinnati Water Works

To one familiar with the turbid and
muddy waters of the Ohio river in the
vicinity of Cincinnati, it will appear
somewhat startling that the 360,000 in-
habitants of this city are supplied from
this source. Moreover, the supply is not
taken from the headwaters of the river
but from a point about nine miles above
the city and in the path of continuous
navigation. Yet by the time the water
reaches the consumer it is 99.2 per cent,
pure, as shown by chemical analysis.

To purify this water and distribute it
throughout the city has necessitated the
construction of an elaborate waterworks
system involving an expenditure of near-
ly $11,000,000. This system, although
not the largest, is in rilany respects one
of the most complete in existence.

Reference to Fig. 1 will give an idea
of the general layout of the system. The
intake is on the Kentucky side of the
river, opposite the village of California,
as there is a greater depth of water on
this side, there being at least 20 feet
at the intake pier even during periods
of low water.

A tract of land on the Ken-
tucky shore was first purchased from

By A. D. Blake

Turbid water is taken from
the Ohio river and after
pa.siing through a filtration
plant is delivered to con-
sumers over 99 per cent,
pure. The total capacity
of the system is 120,000,000
gallons per day, tivo large
pimping stations being em-
ployed, one to pump from
the river to the filtration
plant, the other to distrib-
ute to the variotis sections
of the city.

tunnel, claiming that the bed of the
river to the low-:water mark on the
Ohio shore belonged to the State of
Kentucky. Ten acres of river bed were
thereupon purchased from the latter

Fig. 1. General Layout of System

the city of Covington for $3500; but State for the sum of S2500. and other
after the purchase certain officials of property on the Kentucky side was pur-
Campbell county, Ky., interfered with chased from private individuals for
the construction of the intake pier and $18,750 in order that the city of Cin-

cinnati might control that section of the
river bank and give it proper sanitar>'
protection.

Therefore, although the Cincinnati
water department does not have to pay
any annual rental to the State of Ken-
tucky, it does have to pay State, county
and township taxes upon the assessed
valuation of this property.

From the intake pier containing a
shaft well, a screen well, hydrauli-
cally operated sluice gates, etc., the
water is carried a distance of nearly
1500-feet in a 7-foot brick-lined tun-
nel 50 feet below the river bed to the
Ohio shore. Here the tunnel terminates
in a vertical shaft which extends up
through the center of the circular engine
room of the river pumping station.

River Pu.mping Station

Placed radially around this shaft and
taking their suction from it, are four 30,-
000,000-gallon vertical, triple-expansion
pumping engines, having 29-, 54- and 82-
inch steam cylinders, 37 !< -inch water
plungers and a common stroke of 96
inches. These were built by the Camden
Iron Works and are of the self-contained
type, each engine having an exhaust
heater, surface condenser and air pump
attached. On six-day duty trials two
of the engines showed the following re-
sults:

Duty per 1(100 pounds of steam at 1.10
pounds and 00 degrees superheat, 193, 500. Oik)
foot-pounds.

DutT per 1 000 pounds of saturated steam at
130 pounds. IVJ.UOO.OOO foot-pounds.

An idea of their size may be gained
from the fact that they have an extreme
hight of 106 feet above the pump-pit deck
and weigh 1500 tons each, the foundations
being carried on timber caissons. An elec-
tric elevator is used by the attendants to
reach the various galleries around the
engines. Above the engines is a 30-ton
traveling crane, one end resting on an
extension of the central shaft, the other
on a circular track carried by the en-
gine-room walls.

Owing to the relative location and the
hight of the engines it is impossible to
obtain a view of them as a whole; Fig.
2, however, shows the cylinders and the
upper part of the central shaft.

Electrical energy for operating the
crane, elevator, lights, valves, etc., is
furnished by three 150-kilowatt De Laval
turbo-generator sets.

Steam is supplied at 150 pounds pres-
sure and 500 degrees by eight 210-horse-
power Stirling boilers equipped with
American stokers and Green economizers.
.Adjoining the pumping station is a steel
coal-storage bin of about 7000 tons capa-
city. Coal is brought down the river in
barges and unloaded onto an inclined
cahleway by which it is conveyed in cars
to the storage bin. From the bin it is

August 29. 1911

POWER

311

Engine Room, River Pumping Station

The construction of these basins is
worthy of note. After being excavated
and tamped they were lined with con-
crete which was covered by a thick layer
of waterproofing, and upon this was
laid a specially prepared hard-burned
brick. These were laid in herringbone
order with considerable space between
each brick, and these spaces were then
poured with grout. Such a lining was
necessary to withstand the high water
pressure from the nozzles when wash-
ing the basins.

The water is drawn at the surface from
these basins and is conveyed to the
.niter house. Here it passes through sand
filters and then flows to the clear-water
reservoir. The filters consist of a bed
of gravel upon which rests a 2-foot layer
of sand, the sand being kept separate
from the gravel by a fine-meshed copper-
wire screen.

There are 28 filters in all, each hav-

FiG. 3. River Pimping Station

Fig. 4. Filter House

discharged into dump cars which are run
on a narrow-gage track to the fronts of
the boilers and the coal is unloaded by
hand. The one surprising feature is that
such a cumbersome and expensive sys-
tem of coal handling should have been
employed in a plant otherwise uptodatc
in every respect.

Fig. 3 is an exterior view of the river
pumping station, showing also the coal-
storage bin. The building is of Bedford
stone with a red-tile roof and presents
an attractive appearance.

Filtration Plant
From the river station the water is
pumped through two 60-inch mains,
against a head of 140 feet, to two set-
tling reservoirs having a combined stor-
age capacity of 330.000.000 gallons. These
reservoirs serve a twofold purpose, that
of providing ample storage capacity and
a means by which much of the mud is
allowed to precipitate before the water
passes to the filter plant. The water re-
mains in these reservoirs from two to
four days and is drawn off at the top
through four floating pipes. From here
it is conveyed to the head house where
it is metered and is treated with sul-
phate of iron and lime water. It then
flows to the coagulation basins, shown
in Fig. 5, where it remains for several
hours, allowing sedimentation to fake
place.

Fic. 5. Coagulation Basins

----

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Fio. 6. Filter Basins and Control Boards

POWER

August 29, 1911

ing a capacity of 4.000,000 gallons per after being filtered. An exterior view of

24 hours. When in use a filter is washed
about every 18 to 20 hours. This is ac-
complished by forcing filtered water up
through the bed of gravel and sand and
allowing the overflow to discharge into

the building is shown in Fig. 4.

From the clear-water reservoir the
water flows a distance of 4;/' miles
through a brick-lined gravity tunnel
(drilled through solid rock) to the main

Fig. 7. Main Pumping Station

the river. The operation requires about
5 minutes and it is estimated that the
water required for washing forms about
3 per cent, of the total water filtered.
All the valves are electrically operated
and each filter is equipped with a switch-
board containing the various motor
switches and the indicating lamps show-
ing when a valve is open or closed. These
are shown in Fig. 6.

pumping station located on the outskirts
of the city.

Main Pumping Station

This station supplies two systems: one
a high-pressure system at 195 to 210
pounds to the hill sections of the city
and the Mt. Auburn tanks, the other a
low-pressure system at 75 to 85 pounds
supplying the lower parts of the city, the

three 25,000.000-gallon vertical triple-ex-
pansion engines built by the Holly Man-
ufacturing Company. The steam cylin-
ders are 32-, 60- and 90-inch and the
water plungers 38'/i inches in diameter,
with a common stroke of 60 inches. Three
pumping engines of similar design but
of 12,000,000 gallons capacity serve the
high-pressure system. These engines are
of the self-contained type having exhaust
heaters, surface condensers and air
pumps attached. A view of them is shown
in Fig. 8, the engines and piping being
painted white with the engine-room walls
of white enameled brick.

Steam is supplied at 160 pounds by
twelve 210- to 225-horsepower Geary
boilers and four 300-horsepower Ault-
man & Taylor boilers. The former are
equipped with American stokers and the
latter with Murphy stokers. Recently,
however. Gwynn burners for natural gas
have been installed under the Geary
boilers and coal is now used only for
standby purposes. Four Green econo-
mizers are installed and the natural draft
is assisted by two Buffalo Forge Com-
pany's blowers.

The boilers are set out in the room so
as to afford ample space on all sides and
the settings are of buff brick. This, to-
gether with the abundance of light from
overhead skylights and the absence of
coal dust, gives the boiler room a very
pleasing appearance.

Back of the boiler house there is a
coal-storage bin similar in size and de-
sign to the one at the river pumping

Fig. 8. Engines in Main Pumping
Station

A well equipped chemical laboratory
forms part of the plant and a corps of
chemists is kept busy continually making
analyses of the water both before and

Fig. 9. Boiler Roo.m in Main Pu.mping Station

Western Hills pumping station (an auxil-
iary station of 2,000.000 gallons capa-
city) and the Eden Park reservoir.
The low-pressure ser\'ice is served by

station. This is kept filled for use in
case the gas supply should give out.

A general view of the boiler room is
shown in Fig. 9.

August 29, 1911

POWER

313

Operation

The natural gas burned under the
boilers at the main pumping station costs
1 1 cents per thousand cubic feet and
contains an average of 1060 B.t.u. per
cubic foot. The coal formerly used con-
tained 13.400 B.t.u. per pound and cost
- ' J^T per ton. Hence. 12.64 cubic feet
i;as are equivalent in heat value to I
; and of coal and cost 48 cents less.
Another saving resulting from the sub-
stitution of gas for coal has been a large
reduction in the boiler-room force.

The cost of operation for the entire
system has shown a steady- decrease dur-

ing the three years it has been in ser-
vice; from a total cost of S16.09 per
million gallons in 1908 it was reduced
to SI 4.36 in 1910; and from present in-
dications the report for 1911 will prob-
ably show still better results.

A very complete system of cost keep-
ing has been introduced by the superin-
tendent. S. G. PoUardj and it is now pos-
sible to tell at any time just how much
it is costing to operate any branch of
the system.

The average duty at the main pumping
station during the past six months, re-
duced to an equivalent per hundred

pounds of coal, has been 137.800.000
foot-pounds.

For the past year the average daily
consumption of water has been over 46,-
000,000 gallons. With a total rated capa-
city of 120,000,000 gallons per day, it
will be seen that the water supply for
the city is ample for years to come.

The Cincinnati water department is
entirely self-supporting and the benefits
of the new water-supply system are ap-
parent from the fact that the typhoid-
fever rate has been reduced from 19
to 5.7 persons per 100,000 of population
since its installation.

Kinks at Pendleton Generating Station

The Pendleton generating station of
the Cincinnati Traction Company is one
of the older plants of this company and
of the system of which it is a part.
Plans have been drawn for enlarging and
entirely remodeling this plant so as to
conform to the present standard of elec-
tric-traction practice; that is, generating
alternating current at high voltage for
transmission to substations where it is
stepped down and converted to direct
current for distribution by the trolley
feeders.

As it has been necessary to keep the
plant in operation, the recoivstruction
has necessarily progressed slowly. Con-
sequently the station now contains an
assorted equipment ranging from mod-
em turbo-generators to old-time belt-
driven machines, some of a type ancient
enough to be almost a curiosity. In
spite of their obsoleteness, however,
some of these machines still show good
economy.

The present equipment consists of
fourteen 52.°i-horsepower Babcock &
Wilcox boilers, two fiOOO-kilowatt. three-
phase, 25-cycle, 6600-volt Westinghouse
turbo-generators, constituting the new
part of the plant, and two 300-, one
1200-, one 1300- and one 1500-kilowatt,
direct-current engine-driven units; these
together with a l.VX)- kilo watt turbine
constitute the old equipment. Another
6000-kilowatt turbo-generator is about to
be installed and the plans call for ulti-
mately adding an additional capacity of
30,00() kilowatts.

Although this assorted equipment is
of more or less passing interest, the
features which impress the visitor most
are several ingenious kinks which have
been employed to overcome obstacles in
operating conditions.

Reversing Valve

Perhaps the most novel of these is the
reversing valve used in connection with
the circulating water for the surface
condensers. This water is taken from
the Ohio river, a few hundred feet to
the rear of the plant, and formerly much
trouble was experienced by drift mat-

Bv A. De Groot

Avioiig the interesting feat-
ures oj the Pendleton sta-
tion of the Cincinnati Trac-
tion Company is an ar-
rangement lihereby strainers
on the circulating-water in-
take are dispensed with and
the direction of flow through
the condensers is reversed
at will. A nother novel kink
is an auxiliary air valve on
the dry-air pump which as-
sists the circulating-pump
siirliou.

ter obstructing the strainers on the in-
take pipes. Owing to the ver\- high rise
and fall of the Ohio river at different
seasons of the year, it was necessary to
have the intake close to the river bed in
order that it might be submerged at
periods of low water. Hence, the ex-
treme submergence of the intake pipes at
high water made the strainers inac-
cessible for cleaning or removing ob-
structions.

Accordingly, it was decided to dis-
pense with the strainers entirely and to
substitute a reversing valve, whereby the
direction of flow might be reversed at
will; that is, the intake and the dis-
charge pipes are made interchangeable.

The device is shown in Figs. 1 and 2
and consists of a cylindrical chamber
into which lead six pipes as indicated.
The interior is divided into three com-
partments by a diaphragm and two pis-
tons, these being controlled by a hydrau-
lically operated piston placed at one end

Fi'.. 1. RiviKbi.No Valvi; and C

314

POWER

August 29, 1911

of the casing. When the diaphragm and
pistons are in the position indicated by
the solid lines the direction of flow is
from pipe G through pipe 5 to the pump;

the circulating pumps. When the piston
of the dry-air pump has completed its
stroke, leaving behind it a partial vac-
uum, the auxiliary air valve opens and

condenser from being disturbed. By this
means the suction of the circulating pump
is aided without throwing any additional
load on the dry-air pump. A view of the

To Pump

Fig. 2. Section through Reversing Valve

aialLj:^.-

Streef

ffoom Floor,
'"~Aih~pF'Floo.

Fig. 3. Section through Plant

returning from the pump through pipe
2 and passing to the condenser through
pipe 3; the discharge from the con-
denser is through pipe 1 to the valve
chamber, thence through pipe 4 to the
river. By simply throwing a lever the
diaphragm and pistons are moved
hydraulically to the position shown by
the dotted lines. The direction of flow
is now reversed, as indicated in paren-
theses; that is, the intake is through pipe
4, the water passing to the pump through
pipe 5, from the pump through pipe 2,
and to the condenser through pipe 1 ;
the discharge from the con^lenser is
through pipe 3 and thence through pipe 6
to the river. By this arrangement the
intake is freed of driftwood and other
obstructions without interfering with the
operation of the condensers. Moreover,
it furnishes a means of keeping the con-
denser tubes entire!/ free with a mini-
mum amount of labor.

Auxiliary Air Valve

Another ingenious device is that em-
ployed to maintain the suction lift on
the circulating pumps during periods of
low water. At such times there is a
suction lift of about 20 feet on the cen-
trifugal pumps which ordinarily they
would have difficulty in maintaining.

The dr\'-air pumps, which are of the
Laidlaw-Dunn-Gordon type, are located
in the turbine room (see Fig. 3) and to
these are fitted auxiliary air valves con-
necting with the suction chambers on

Fic. 4. Dry-air Pu.mp Showing Auxiliary Air Valve

throws this vacuum onto the suction of
the circulating pump. This assists the
suction of the latter pump and the clos-
ing of the main air valves on the dry-
air pump prevents the vacuum on the

auxiliary air valve on one of the pumps
is shown in Fig. 4. Of course, this de-
vice is used only at periods of low water,
the river furnishing sufficient head at
other times to overcome the suction lift.

August 29, 1911

POWER

315

Coal-handling System
The method of handling coal in this
plant, although embodying nothing un-
usual, is nevertheless interesting and
shows how the conditions were met by a
simple and inexpensive arrangement.

As shown in Fig. 3. coal is brought in
cars to a siding on a trestle at the op-
posite side of the road from the power

house. Under this trestle is a con-
crete-lined tunnel connecting with the
bottom of the elevator shaft. Coal is
dumped from the railroad cars onto a
pile around the trestle and from here
through a hopper in the roof of the
tunnel to hand cars. The latter are run
over a narrow-gage track to the elevator
and are raised to the level of the boiler-

house roof. They are then run across a
bridge, spanning the roadway, and dis-
tribute the coal to the bunkers located
over the boilers. These bunkers are of
such size as to hold a ton of coal per
linear foot.

The entire operation requires the ser-
vices of but one man who can in this
way handle nearly 200 tons a dav.

Plum Street Generating Station

■^X'hen visiting Cincinnati one should
not fail to inspect the Plum street station
of the Union Gas and Electric Com-
pany. This plant has a capacity of 28,-
000 kilowatts and supplies electricity for
light and commercial power to the entire
city as well as to the various outlying
districts. Although not a new plant, it is
in many respects uptodate, and additions
have been made to it from time to time.

Equipment
There are two boiler rooms, one a part
of the original building and the other,
which was added about five years ago.

A pla)it of 28,000 kilouatts
capcicity- sitf^plyiiig light
and commercial power to
the city of Cincinnati'. A
Hf a' arc-lighting equipment
is about to he installed atid
the contract covering this
apparatus is the largest that
has ever been given oid at
any one time.

plant in wagons and is delivered onto a
conveyer which raises and distributes it
to the storage bins over the boilers.

Very little coal is used, however, as
one set of eight boilers in the new- part
together with those in the old part are
fitted with gas burners using natural gas;
hence the coal is used only for banking
and emergency purposes. There are 24
burners to a boiler, and the only altera-
tion in the setting is that the ordinary
coal grates are coxered with tile. A view
of one row of boilers with gas burners
is showm in Fig. 3.

Fic. 1. Second Enoine Room, Showing S^citchboard

The former contains six Babcock & Wil-
cox, six Fdgc Aloor, and two Stirling boil-
ers, all equipped with American stokers.
In the second boiler room there are eight

542-hnrsepottcr Stirling boilers set in
batteries of two with Jones stokers and
eight similar boilers equipped with Am-
erican stokers. Coal is brought to the

There are two engine rooms, one con-
taining three large vertical engines and
two turbines; the other a number of
smaller engines of the vertical type, bal-

316

POWER

August 29, 1911

ancer sets, the main switchboards and
the arc-lighting equipment. A view of
the latter engine room is shown in Fig. 1.
Of the large units shown in Fig. 2,
the first is a 3200-kilowatt. three-phase,
60-cycle generator direct connected to a
vertical cross-compound Allis-Chalmers

10,000-kilowatt , 4500-volt, three-phase,
60-cycle Westinghouse-Parsons machine,
taking steam at 175 pounds and exhaust-
ing into a Leblanc condenser.

In the second engine room are a num-
ber of sets of various capacities, the type
consisting, for the most part, of a 4500-

FiG. 2. Large Reciprocating Engines

engine. The second is a 2500-kilowatt,
300-volt, direct-current machine driven
by an engine of a type similar to the
first. The third is a vertical cross-com-
pound Mcintosh & Seymour engine direct
connected to one 125-volt and one 250-
volt eenerator, these having a combined
capacity of approNimately 2500 kilowatts.

volt alternating-current generator on the
shaft with a 250 to 300-volt direct-cur-
rent generator and driven by a vertical
cross-compound engine. In addition to
these there are several motor-generator
sets receiving three-phase alternating
currents at 4500 volts and delivering di-
rect current at 250 to 300 volts.

plant from the 4500 volts, which is the
e.m.f. produced by the large generators.

At present the Wagner system of alter-
nating-current series arc lighting is em-
ployed throughout the city, but this is
about to be replaced by a General Elec-
tric direct-current series arc system. In
this connection it might be well to note
that the contract for this new arc-lighting
equipment is the largest that has ever
been let.

The specifications call for one hundred
and twenty-eight 75-light mercury-vapor
rectifier sets supplying 4-ampere lumin-
ous arc lamps, and four thousand 80-watt
alternating-current series tungsten lamps
for the business section of the town. In
addition to this there are to be several
sets of 60-watt lamps for boulevard
lighting.

Of the equipment included in this con-
tract all the rectifiers and 6000 arc lamps
are to be installed immediately.

An Ideal Central Station

.A recognized disadvantage of the aver-
age central station is the enormous loss
due to distribution. To minimize this,
high-voltage transmission is usually em-
ployed, but this necessitates the installa-
tion of more expensive equipment. More-
over, central stations usually have no
market for their exhaust steam.

On the other hand, while the isolated
plant does not incur the high distribution
losses and usually has a demand for
the exhaust steam during the greater
part of the year, it often lacks a high
load factor.

The ideal condition then is a central
station supplying power to customers
within a limited area in the immediate

'Sit

^[; '^-^Jl^>^

i^B.- ^kz St-'*'

j^J' '^

K^ i||» -^.^

'^. ^^

Mn^"^'-' JH

Fig. 3. Boilers Burning Natural Gas

Fig. 4. Turbines

At the far end of this engine room are
two turbines, which are comparatively
recent additions. .\s shown in Fig. 4, one
is a 5000-kiIowatt, 4500-volt. three-phase,
60-cycle Curtis machine running at 1800
revolutions per minute, and equipped with
a Worthington condenser; the other is a

For commercial light and power with-
in the city the three-wire system is used
with 240 volts across the outside wires
and 120 volts between either outside wire
and the neutral. The suburbs are sup-
plied with alternating current at 2300
volts, this being stepped down at the

vicinity of the plant and selling the ex-
haust steam for heating and industrial
purposes. Such is the colony plant at
Oakley. O., a suburb of Cincinnati.

About three years ago the Cincinnati
Milling Machine Company acquired a
large tract of land at Oakley to which it

August 29. 1911

POWER

317

moved its works. Parcels of this land
were then sold to several other manu-
facturing firms, including the Triumph
Electric and Refrigerating Company, the
Modem Foundry Company and the Bick-
ford Drill Company. A central power
plant was erected to supply direct cur-
rent at short-distance transmission for
light and power and exhaust steam for
heating and manufacturing purposes; di-
rect current being selected on account of
the individual machine-tool drive.

The plant is run virtually on a co-
operative plan, each concern owning stock

pro rata to the amount of power utilized
during the year. That is, each consumer
is billed at a fixed nominal rate and after
deducting the operating expenses and 6
per cent, to cover interest charges, the
surplus is rebated to the consumer ac-
cording to the amount of steam and elec-
trical energy consumed.

The present capacity of the plant is
1100 kilowatts, the equipment consisting
of two 250- and one 500-horsepower
Stirling boilers, equipped with Detroit
stokers and furnishing steam at 135
pounds gage to one Ball & Wood com-

pound engine driving a 600-kilowatt gen-
erator, an engine of the same make driv-
ing a 300-kilowatt machine and a Harris-
burg Corliss engine driving a 200-kilo-
watt generator. In addition to these
there is an air compressor having a ca-
pacity of 200 feet of free air per minute.
All lines supplying customers are
metered.

It is planned to add to the present
equipment of the plant in order to meet
the increased demand for power and a
more detailed description of the plant
will appear at a later date.

Saving with Low Pressure Turbine

A striking instance of the gain due
to Installing a low-pressure turbine in
connection with high-pressure reciprocat-
ing engines, is to be found at the plant
of the Western Ohio Traction Company
at St. Marys. Ohio.

This plant, which is of approximately
3500 kilowatts capacity, supplies power
to the interurban trolley system connect-
ing Toledo, Lima, St. Marys and Wapa-
koneta and to local lines within those

Tlie installation of an 1 150-
kilowatt low-pressure tur-
bi}ie, taking steam from two
reciprocating engines, re-
sulted in a reduction from
42 ^0 3^ pounds of coal per
kilo7catt-lioiii .

and the back pressure on the reciprocat-
ing engines to which it is connected is
approximately 3 pounds gage.

No complete plant tests have been
made, but careful records are kept of
the coal burned and of the electrical out-
put at the switchboard. These have
shown that, running at an average load
of 50.000 kilowatt-hours per 24 hours,
the low-pressure turbine has reduced the
coal consumption from 4' j to 3',j pounds
per kilowatt-hour. Of course, the latter
figure is not exceptionally good; in
fact, it is only about the average, and
the 4' J pounds of coal per kilowatt-
hour formerly consumed would be con-
sidered a very poor showing. The high
coal consumption, however, is due to a
poor quality of coal and to adverse con-
ditions in the boiler room, and does not
detract from the good showing of the
low-pressure turbine.

A little calculation will show that this
reduction of one pound of coal per kilo-
watt amounts to 50,000 pounds or 25
tons of coal a day. Assuming the price
of coal to be as low as SI. 60 a ton this
saving would amount to S40 a day or
over ,S14,000 a year. At this rate the
turbine would pay for itself in about
three years, a comparatively short time in
which to cover the initial investment.

FiC. 1. E.XTLRNAL

towns. Current is generated at 400 volts
and the voltage is stepped up to 33,000
for transmission 10 the various substa-
tions where it is stepped down to 650
volts.

The boiler plant of the generating sta-
tion contains eight 375-horsepower Stirl-
ing boilers, five of which are served by
Model automatic stokers and three are
hand fired. These furnish steam at 150
pounds to two cross-compound Cooper
engines, each connected to a 7.SO-kilowatt
generator and to two engines of the
same type driving 400-kilowati gen-
erators. The exhaust from one 7,S0-kilo-
wait and one 400-kiIowatt unit is led
to a 1 1.50-kilowatt low-pressure Westing-
house turbine. The latter runs on a
vacuum of about 27 inches, maintained
hy a Leblanc condenser and air pump,

Fig. 2. l.oi -rRi ssirk Turbini; and Rkcipkocaung Engines

318

POWER

August 29, 1911

The Zoelly Steam Turbine

At the meeting of the Institution of
Mechanical Engineers of Great Britain,
recently held in Ziirich, a paper under
the above title was presented by H.
Zoelly, engineer and director of Escher,
Wyss & Co., of that city, inventor of the
turbine which bears his name.

Guided largely by the knowledge
gained in his experience as a designer

The Zoelly turbine, -Lchen
first introduced about fifteen
years ago, was of the pure
impulse type, based largely
upon its designer's experi-
ence with waterwheels. The
dn'eloptnents leading up to
the present design are dealt
li'ith and its characteristic
features are discussed.

this case also, impinged upon the blades
in a radial direction. It was found ad-
visable to divide the pressure drop into
at least six and sometimes into ten or
twelve stages. The diameters of the
rotors were increased toward the exhaust

Fig. !. Rotor Blades

of water turbines, in which line he has
specialized for twenty-five years, the
author commenced about fifteen years
ago to experiment with steam turbines.
In water turbines the impulse type is
used for everything above 300 feet head,
and he, considering the steam turbine
analogous, was naturally led to the pure
action or impulse type for the high velo-
cities involved in the steam-driven ma-
chine, end in order to better cope with the in-

The first machine was designed on the creased volume of steam,
radial-flow principle, but in its design The only alterations which occurred
too much attention was paid to consider- for some time were in the manner of

Fig. 2. Guide Channels

Process in Making Blades

ations of construction and too little to
theory.

The second machine was constructed
with curved blades instead of the flat
ones previously used, but the steam, in

guiding the steam on to the wheels. The
first construction used was similar to
that of the Pelton waterwheel, the steam
impinging tangentially after having been
directed through separate guide chan-

nels. It soon became apparent, however,
that after impact the steam became too
much dispersed. It was then decided
to expand the steam axially instead of
radially, at first only in the low-pres-
sure stages but subsequently throughout
the turbine. TTiis method had pre-
viously been adopted by English con-
structors as being the most practical.

Fig. 4. AssE.MBLiNG Rotor

What has always been, and is still,
the most characteristic feature of the
Zoelly turbine is the design of the rotor
blades and of the guide channels, shown
respectively in Figs. I and 2. Fig. 3
shows the successive operations in mak-
ing the nickel-steel blades in which they

a,

Nil 1 i 1

1 1

■^

1

° '

, : . :i

J 1

< 'r-

! 1 >!

1

I

'-:■ _,'

1

! ..: ^

Z "I

1

1

■

Q.=

1

1

1

I [

1

1 ! 1

! ■ 1 ■ ■ 1

1

1 1 '.

i ' 1

S '

i !

1

! . .: i

V

Ml I

^.30

, ' ■ I i 1 ;

■ 1 1 1

1

■ 1 I

.■:,,; 1

i ■

S30-

I'll ' i 1 i 1

1

\ ''■ '

1

o

1

\ 1

1

A 1

1

1

° 10

\

1

\

1"

1

■ : ■ N>

1 1 1

7 4^

•--^

-^— , ' ■

. ; 1 1 ■ 1 1 ■ ;

I 12 14 IH 2

Relation of Pressure Dnop.-^ ■»-..

Fic. 5. Stages Required for Expanding

FROM 10 Atmospheres to Final

Pressures

are assembled. Constructed in this way
the wheels are capable of being run
at a relatively high circumferential velo-
city, permitting greater latitude in re-

August 29, 1911

POWER

J19

gard to the number of stages and the ordinates are the requisite number of
velocity of the steam in each. stages for steam expanding from 10 at-
From the start two characteristic dia- , ._^ . , _^ /.,

grams have been employed. They were

mospheres, with varvinc values of —^,

__

^

h-

-pt;

-r-

"'

p

,

<^

/

— 1

—

"~

—

r-

■£1

-?;

~~

y^

H

'/^

(

_

P,

^73_

__J

L^

—

■— ^

►-^

j

^

' '

V

Jd

=1.

5

--

U-

■~^

~^

r^

_£,

r'-7

^ 1

^

-~'

—

P.

P

,.-'

^

:l.

r>

r

—

V-

■^

1^

P

I ' I

P

1 — '■ —

1 —

H ''

—

Si

-p

=i.i5_

_

—

—

—

— -

— i

—

1 1

—

—

—

"pT
-P-

j=i.i

—

—

1
i

—

u

p-

—

p-

~"

~^

*■"

\^^

1

1

0.105 I E 4- 6 8

Initial Pressure, Atmospheres, Absolute
Fic. 6. Steam Velocities for Varying Initial Pressures

plotted from theoretical calculations,
which have since been proved by actual
results. In Fig. 5 the abscissas are the

assuming that ratio to be constant both
before and after passing through the
guide channels. That reproduced in
Fig. 6 shows the steam velocity result-
ing from various ratios of expansion
from various initial pressures. Fig. 5
shows, for instance, that about nine-
stages are required for the critical pres-
sure ratio

^=-

For the relative pressure falls, where
tl is as indicated, the requisite corres-

ponding number of stages for a tniii
expansion of from 10 to 0.1 atmosphere
absolute would be as follows:

O = i.i 1.2 1.3 2.1 3 4.6

Fir,. 8. Compound Wheel

pressure relations per stage . ' where pi

equals the initial steam pressure and p,
the final steam pressure both in atmos-
pheres absolute in the same stage. The

This steam velocity, on the other hand,
would require a circumferential speed
of about 250 meters (820 feet) per sec-
ond for a simple velocity wheel in order

Stages 42 2.S 18 fi 4 3
From Fig. 6 for a mean initial pres-
sure of

p = 4 atmospheres absolute.
the steam velocity would be equal to
577* meters (IS93 feet) per second.

•TliPrc 1« "onif ronfn<ilnn In till"' p«r«-
ernph Thn volnrllv Bniulrptl tiy ilrv rnilnr-
Btfil nlPiim In pipniifllnii from nn InltlHl prow-
•iiff of four ntitK-'plKTcfi. .-,s s pniin<)pi. to
*'iM H - 1 7.1 - rtl it(.iin<l« ("wv from 2P1 lo
2"i7 <lPKrwB) l« nixint t4rin fppt or 442 mnt^r"
pir spronil .Iiixi nlKMil wlinl I" shown for

Fic. 7. Single Velocity Stage

to obtain a reasonable efficiency. If a
smaller ratio of pressure fall than — ^^-^

Fig. 9. Oil-cooling System

4 In KIe. n. An lliln
llln
fliilhor npprnrM lo Ik
of llip niiv.". nit Mio
nnli- at nnvwln-rr n^'nr r.TT m<'lpr«. tin
once l« dlfflriilt lo iinclprKtnnrt. Kiiiriiii.

POWER

August 29, 1911

for instance.

30

be taken, the neces-

sary number of stages would be in-
creased from 9 to 18; that is, exactly
doubled. Such a turbine would be far
too complicated and expensive. Besides,

tially higher pressure fall per stage, it
becomes necessary to depart from the
simple construction of parallel guide
blades, which is characteristic of the
Zoelly turbine, and to adopt the ex-
panding or De Laval type of nozzle.

pletely around the circumference. In
the case of large units, however, the
entire circumference is used for admis-
sion in all stages.

The governing is effected simply by
throttling the live steam and not by vary-

Fic. 10. NoR.MAL Eight-stage Zoelly Turbine

it would not then work with the best
economy, owing to the greater friction
of the runner wheels and the greater
length of steam passage involved.

After carefully weighing all these
considerations the ratio of

■ £ = ■"

The reason that Parsons employs such
a small pressure fall per stage is to
keep down the losses through leakage,
which are unavoidable in reaction tur-
bines.

For turbines of 3000 revolutions per
minute eight stages are usually em-
ployed by Escher, Wyss & Co.; for

ing the number of channels through
which the steam is admitted. The throt-
tle valve is actuated by oil under pres-
sure in a small cylinder (servo-motor 1.
the oil being supplied by a small pump
driven directly from the shaft. This is
the method of governing that has been
found to work so successfully for water

-11_

M . H^

1/

' 1 f^

J^

nAVA'

'^~~r^

L

Fig. II. Eight-stage Turbine with Bleeder Device

was chosen for the pressure fall per
stage, as representing the best combina-
tion of efficiency and practical construc-
tional economy. This is called the criti-
cal ratio. When it is exceeded, the re-
sulting steam velocity approaches that
of sound. It is the highest velocity ob-
tainable in the throat of a nozzle. Di-
rectly one wishes to utilize a substan-

1500 revolutions per minute, 12 stages,
and for 1000 revolutions per minute 16
stages. The first diaphragm plate of
the high-speed turbine has guide pas-
sages or nozzles which extend for a por-
tion of the circumference only in the
bottom half of the diaphragm, while in
the other diaphragms the nozzles or
guide passages usually extend corn-

turbines, and is now being adopted by
nearly all the makers of steam turbines
on the Continent. Its inherent advan-
tages are that it is extremely simple
and reliable and, contrar\- to fears ex-
pressed by some engineers, works par-
ticularly economically at partial loads,
as shown from the results set forth
in the accompanying table. This, however.

August 29, 1911

POWER

321

is possible only when simple velocity
wheels are used in connection with par-
allel guide nozzles throughout the tur-
bine, and provided that the most favor-

more. If, therefore, in an impulse tur-
bine it is found necessary to employ a
combination design of compound- and
single-velocity stages for such special

this purpose almost as many pressure
stages must, on the whole, be provided
as in a design employing only single-
velocity stages.

able choice is made in regard to sub-
division of stages. Fig. 7 illustrates a
simple velocity stage in the Zoelly tur-
bine, showing a section of the blading.
The conclusion at which the author has
arrived is that the compound-velocity
wheel design is advisable only in special
cases, as, for instance, in marine work,
where a low propeller speed is abso-
lutely necessary. Fig. 8 illustrates a
portion of a compound-velocity wheel
and a section of the blading.

The chief reasons against the adop-
tion of the compound-wheel design in
the case of stationary turbines are the
lower steam efficiency and the necessity
of a complicated governing apparatus in
order to obtain a favorable consumption
at partial loads. In this type of tur-
bine the governing has to be carried out
by controlling the number of nozzles
through which the steam enters. Ex-
perience has shown that this method
does not satisfactorily answer practical
requirements; that is, continuous safe
running. Besides, the governing is not
as accurate, and is less suitable for run-
ning in parallel with other machines.
The author says that he has for many
years experimented with turbines de-
signed with high steam velocity and com-
pound wheels, and that the many series
of tests which he has carried out at
different periods have all gone to show
that under the most favorable condi-
tions it is not possible to obtain a higher
thermal efficiency than 58 per cent.,
with compound-velocity wheels, whereas
with a turbine designed entirely with
simple velocity stages it Is possible to
obtain an efficiency of 7S per cent, and

Fig. 12. Mixed-pressure Turbine

cases as exceptionally large units for
land purposes, or where it is necessary
to work at low rotative speed, the com-

It is often objected that in the Zoelly
turbine too high a pressure and tem-
perature exist in the first pressure stage;

Fig. 13. Rotor of Marine Turbine

paratively poor efficiency of the high- but Mr. Zoelly contends that even with

pressure compound-velocity stage or single-velocity stages large pressure

stages must be compensated for, as far falls can be utilized for the first stage

Section of Marine Turbine

as possible, by obtaining a relatively
higher efficiency in the subsequent low-
pressure single-velocity stages. For

within comparatively economical limits,
provided the lower-pressure or subse-
quent stages have a correspondingly

322

POWER

August 29, 1911

lower pressure fall, and thus work with
a higher efficiency. With an initial pres-
sure of about 170 pounds per square
inch and a temperature of 550 degrees
Fahrenheit (300 degrees Centigrade),
the pressure and temperature of the
steam after expansion in the first stage
is 70 pounds per square inch and 465
degrees Fahrenheit (240 degrees Centi-
grade). Such conditions so far as they
affect the rigidity and durability of the
casing, and the tightness of the stuff-
ing boxes, are nowadays easily mastered
by steam-turbine builders.

The Zoelly turbine has from the com-
mencement been constructed with a hori-
zontal shaft; experience with water tur-
bines having shown that by this method
the simplest form of bearing can be
used, permitting an easy inspection at
all times. In the case of turbines run-
ning at 3000 revolutions per minute a
flexible shaft is used, so that the criti-
cal speed is sufficiently below the work-
ing speed; but in the case of turbines
running at 1500 revolutions per minute
and under the shaft is rigid and the
critical speed is above the working
speed. The shaft is supported upon two
bearings, which are lubricated by oil
under pressure, and is connected by
means of a rigid or flexible coupling
(usually rigid) to the generator or ma-
chine to be driven. The casing is built
in halves, the joints being horizontal,
so that the rotor can be inspected or
removed without dismantling the bear-
ings. The oil-cooling coils are located
in the base, and are shown in Fig. 9
ready to be lowered into position.

Some results of recent tests are given
in the accompanying table. They were
made with carefully calibrated instru-
ments by competent and impartial ob-
servers. Particular attention is called to
the manner in which the efficiency is
maintained at partial loads. The thermal
efficiency is referred in one case to the
steam as actually supplied to the tur-
bine, and to the other in a throttled
condition behind the stop or throttle
valve.

Fig. 10 shows a section of a normal
eight-stage Zoelly turbine, constructed
to develop 1500 to 1800 horsepower at
3(X)0 revolutions, with a steam pressure
of 170 pounds, at 570 degrees Fahren-
heit, and with a vacuum of 95 per cent.

Fig. 1 1 shows sectional elevations
of an eight-stage Zoelly turbine, fitted
with a connection for drawing off about
4500 pounds of steam per hour, at a
pressure of 3 to 5 pounds, for heating
and for other purposes. This turbine
was constructed for the Zurcher Papier-
fabrick, Sihl, to develop about 1100
horsepower at 3000 revolutions per min-
ute, with an initial steam pressure of
115 to 120 pounds, at a temperature of
570 degrees Fahrenheit, and with a vac-
uum of 95 per cent.

Fig. 12 shows a section and elevation

of a mixed-pressure Zoelly turbine, con-
structed for Zehe, Dannenbaum, to de-
velop 1800 horsepower at 3000 revolu-
tions per minute, with a main steam
pressure of 1 15 to 125 pounds, using
exhaust steam at a pressure from 5 to
12 pounds, and with a vacuum of 91
per cent.

The high-pressure portion of the Zoelly
marine turbine is fitted with a series of
compound-velocity wheels. Fig. 7 il-
lustrates a portion of one of these w-heels
and a section of the blading. Owing
to the low rotative speed required sin-
gle-velocity wheels cannot be utilized to
their full advantage. To obtain a rea-
sonable efficiency with a single-velocity
wheel would allow of only a very small
drop of pressure in each stage, which
would necessitate far too many stages.
Furthermore, contrary to the theories put

In conclusion, the author acknowl-
edges his indebtedness to Mr. E. R.
Peal, engineer of the British Zoelly Tur-
bine Syndicate, for assistance rendered
in preparing the paper.

Central Engine Room Oiling
System

There was a time when an engineer
or an oiler with an oil can in his hand
was a familiar figure about a power
plant. Beside the engine cylinder there
was a stand on which were several
polished oil cans of various sizes and
types.

But hand lubrication was not always
reliable. Sometimes the oiler became
inattentive, and the oil cup ran empty;
there was a hot box; not infrequently
new babbitt was necessary.

TE.-^Trt OF ZOELLY STE.\.\I TURBIXE.S

Thermal Effi-

."^TE.tM-PRESSURE

STE.OI

CTENC

T, Per

\T Stop Val\-e

CoXSt-SIPTION

Cent.

Based

on Con-

ditioa of .Steam

Pounds

Temp-

in

Load in

per

erature,

Kilo-

Horse-

Front

Behind

Kilo-

.Square

Degrees

Vac-

watt-

power-

of Stop

Stop

Installation

watts

Inch

F.

uum

hour

hour

Valve

Valve

Per

Per

Per

Cent.

Lb.

Lb.

Cent.

Cent.

4000-kilowatt turbine

4189

164.7

556.7

95.8

*13.25

9.36

68.7

71.2

"Cliarlottenburg"

3092

168.3

558.3

96.2

13.77

9.. 58

66.2

70.8

1000 revolutions per minute

2199

161.9

518.5

97.4

14.40

9.. 84

63.2

70.75

Tested December, 1910 1.

1138

166.9

520.7

97.8

16.00

10.12

59.9

72.7

2000-kilowatt turbine f

2052

179.0

584.6

94.9

13.04

9.18

70.5

73.0

"Helsingfors" J

1514

181 .7

563.3

95.5

13.67

9.52

67.2

72.8

.'iOOO revolutions per minute )

1026

177.5

565.5

95.8

14.53

9.76

65.2

73.8

Tested November, 1910 [

510

171.8

543.0

96.6

17.33

10.68

58.8

72.8

1700-kilo\vatt turbine f

1691

206.0

670.2

93.3

13.04

8.91

69.7

69.8

" Hagendingen" J

1366

202.3

673.5

94.2

13.77

9.18

66.5

69.2

3000 revolutions per minute )

851

205.2

662.0

95.2

15.52

9.81

61.0

66.9

Tested December, 1910 t

457.5

208.0

642.9

94.9

18.91

10.68

57.1

67 9

1200-kilo\vatt turbine f
••.\urich" 1

1235

162.3

451.0

94.0

15.34

10.77

67.0

68.3

949

164.0

442.4

95.5

15.99

11.08

62. S

66 9

.'iOOO revolutions per minute "1
Tested December, 1910 t

606

166 7

427.4

96 5

17.1

11.48

59.0

66 6

—

—

—

—

*Not including steam required for condensing plant.

forth by Curtis, it was found advisable
to adopt the ordinary parallel guide
channels, similar to those used in the
Zoelly land turbine, in preference to
expanding or De Laval nozzles; a type
of construction which has since proved
its merit. The high-pressure portion of
these turbines, therefore, consists of a
series of compound wheels, the low-
pressure portion of impulse drum blad-
ing.

Messrs. Escher, Wyss & Co. have
recently built in their workshops a\
Zurich a set of two marine turbines,
each of 7500 horsepower, which are now
in operation in the torpedo boat de-
stroyer "G 173" of the imperial German
navy. These turbines are illustrated in
Figs. 13 and 14. Fig. 13 shows the
rotor complete, and Fig. 14 the section
of a turbine. A number of similar tur-
bines are now being constructed for the
German, French, American, Italian and
Argentine navies.

Oiling methods have passed through
various stages of evolution. The variety
of oil cans has largely been displaced
by individual or unit oiling systems, and
even these have been supplanted in large
engine rooms by one central oiling sys-
tem capable of lubricating all of the ma-
chines in the plant.

An installation of this character has
been placed in the power plant of the
new Whitehall building. New York City,
wherein every machine in the plant is
automatically lubricated from a central
source of supply.

There are three 500- and one 250-
horsepower Rice & Sargent tandem-com-
pound engines direct coupled to three
300-kilowatt and one 150-kilowatt direct-
current generators respectively. The
cylinders of these engines are each
equipped with a four- feed Richardson
Model "M" oil lubricator, as shown in
Fig. 1. One pipe discharges to the steam
passage of the high-pressure cylinder;

August 29, 1911

P O W E R

a second pipe conveys oil to the piston
rod and me other two supply oil to
lubricate the steam valves. On the low-
pressure cylinder the piston rod on both
sides of the cylinder is lubricated.

The Model "M" lubricator was de-
signed with the special object in view of
introducing some oil for every stroke of
the engine. This is accomplished by
employing an oil-pump plunger for each
feed line, and no matter at what rate the
oil is being fed through the sight- feed
nozzle of the lubricator, this oil plunger
moves up and down in unison with the
strokes of the engine and chops off a
small particle of oil and forces it to the
cylinder at each revolution of the en-
gine.

The bearings, eccentrics and other
parts requiring oil are all lubricated from
the same central system. Oil cups, how-
ever, have been provided so that in case
of emergency oil can be supplied to the
bearing, etc., independent of the oiling
system.

There is a motor-driven direct-current
generator used for charging the storage-
battery system. The bearings of this
unit are supplied with oil from the

Fig. 2. Supply Tanks Suspended fro.m the Ceiling

Fic, 1. Oil Pu.mps Attached to Engine CwiNDti<>

POWER

Fic. 3. Exciter and Balancer Sets, Showing Oil Seals on the Bearings

August 29. 1911

tanks by either of two triple-plunger
motor-driven oil pumps shown in
Fig. 5, through a 1-inch pipe. The
drain pipes to the filter are X'/z
inches in diameter as are also the feed
pipes for both machineo' and cylin-
der oils. When new oil is to be pumped
into the storage tank from barrels a hose
is coupled to the suction pipe of either
pump and the other end put in the bar-
rel. It is possible to use either pump by
manipulating suitable Nelson valves with
which the system is fitted. An eleva-
tion of the system which was designed
and installed by the Peterson Engineer-
ing Company is shown in Fig. 6.

I

Machinery, ^'^ ^'^''M "J^~d:£^•ff'_ ^ ^"'^"I, Ml l\ l/^

Filfersareon /i" lil/^" .^ | _ 1 b^achineiy-. \rr^ K

Mezzanine Floor nl i : j^ jT ;,« | gn ' -^'f I,"

below En,jine Hoor rfAv. fijj^re Unit ^^, %k i

////////^//^/.','

To Annunciator-

Engine RoomCeilini

ms

feS2]^3

M^X A...i--i''^-

is*" 'fcl^ ITT"" — "^

^m-l,,. y m ^- f
Aij-L ll trr^ Fan C

8[Z3 Ilit; r

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fl ills] ^^f^ilr I

d6^#

ill

Fitters
He2z.n.

Fig. 6. Arrance.ment of Piping

general oiling system. A proper oil level
is maintained by an oil-seal arrangement
similar to that in Fig. 3, which shows
the balancer and exciter sets. The bear-
ings are all equipped with gage glasses.

A plan view of the oiling system and
connections to the various machines is
shown in Fig. 4. All pipe lines repre-
sented by short dashes indicate drain
pipes. Those shown by a long and short
dash represent cylinder-oil pipes, and
those shown by a long and two short
dashes are machinery-oil pipes.

These oils are supplied to the system
from two oil tanks suspended from the
ceiling of the engine room. Fig. 2, high
above any point to be lubricated. Each oil
tank has a high- and low-oil alarm sys-
tem which registers on an annunciator lo-
cated on the mezzanine floor below the
engine room. Each tank is fitted with a
gage glass to designate the hight of oil
in each independent of the alarm system.

After the oil has passed through the
system it is returned to two Richardson-
Phenix oil filters, each equipped with a
high- and low-oil alarm which registers
on the annunciator.

Oil is pumped to the overhead storage

FiG. 5. Oil Pl.mps a.nd Filters

August 29, 1911

POWER

325

Operating Alternately on the

Two Wire and Three

Wire Plans

By Louis T. Kaiser

The Mercantile Library building in Cin-
cinnati, Ohio, a 12-stor>- office building,
formerly contained a power plant consist-
ing of boilers, hydraulic elevator pumps
and two 100-kilowatt, 110-volt direct-cur-
rent generators, direct-connected to tan-
dem-compound engines. These genera-
tors supplied current to 2400 incandes-
cent lamps, a 15-horsepower motor oper-
ating a refrigerating machine and four 4-
horsepower motors driving ventilating
fans. The switchboard consisted of two
generator panels, an instrument panel
and two panels carrying the switches and
fuses for the various circuits, making
five panels in all.

The St. Paul building, a 10-stor>' struc-
ture located half a block distant, is
owned by the same people The power
plant of this building being old and out
of date, it was decided to abandon it and
obtain power from the Mercantile Li-
brary building. Accordingly conduits for
both steam and electricity were laid from
one building to the other, and in the St.
Paul building were installed two traction-
type Otis electric elevators, operating on
direct current at 220 volts. About 12(X1
lights are used in the St. Paul buildinp.
in addition to several motors for driving;
house service pumps.

This additional demand for power made
it necessary to enlarge and alter the plant
in the Mercantile Library building. In
order to supply the second building econ-
omically, a change was made from 110
to 220 volts and the equipment was in-
creased by installing a 220-volt direct-
current Crocker- Wheeler generator of
200 kilowatts capacity, direct-connected
to a Ball automatic cutoff engine, a motor
balancer set having a capacity of 300 am-
peres in the neutral wire of a three-wire
•ystem. and five additional switchboard
panels.

Of the additional panels one contains
the necessary switches and instruments
for connecting the two original IlO-volt
generators in scries and into service with
the 220-volt busbars of the three-wire
system; another panel contains the
switches and rheostat for controlling the
balancer set; a third carries the circuit-
breaker for the feed wires supplying the
St. Paul building; the fourth carries a
watthour meter for recording the output
of the entire plant when operating at 220

volts on the three-wire plan, and the last
panel contains the generator switches,
rheostat, etc., for the 220-volt machine.

The conditions of service are such that
from midnight to 7 a.m. no motors or ele-
vators are in operation. Hence, no 220-
volt service is required, and the lighting

switches I, 3, 4, 5 and 6 are closed, which
allows the machine to operate with a com-
pound field winding. By closing the
switches 2 and 7, the compounding is cut
out and the machine is operated with the
shunt field winding only.

If it is desired to shift the load to the
generators B and C, they are started and
their e.m.f. adjusted to 110 volts. The
switches 8 and 10 are then closed and the
voltage is again adjusted to correspond
with that of the 220-volt busbars. Next,
the switches 11 and 12 are closed, which
puts the generators fl and C in series and
in> parallel with the generator A. They
will not remain in parallel long, however.

Fig. 1. Front View of Svsitciiboard

load being small, there is very little loss
in transmission. Therefore, the entire
system is run at 1 10 volts.

Til provide this flexibility of operation,
a very interesting arrangement of switch-
board wiring is employed. This is shown
diagrammatically in Fig. 2.

Operation

If the generator A is to carry the load
in connection with the balancer set, the

on account of the compound field wind-
ings. By closing the switches 2, 9 and
13, the compoimd field windings are
short-circuited and all the generators op-
erate as shunt machines. Cutting nut all
the switches on the generator A throws
the entire load over to the generators B
and C. The next step is to close the
switch 14 and open the switches fi. 7, 5
and 4. which shuts down the balancer set
and puis the unbalanced load on either

326

POWER

August 29, 1911

generator B or C, depending upon which
side is out of balance.

For night service all the switches on
the generator C are cut out and the
switch 15 is closed; this throws the en-
tire system on 110 volts.

This building has a large cafe which
requires light all night, and the circuit
supplying this cafe is tapped between the
busbars marked F. By means of this ar-
rangement the service is never inter-
rupted. All switches are protected with
circuit-breakers, and where necessary
with those of the overload reversal type,
protecting the entire system should the
attendants throw in the wrong switch.

To change back to 220 volts, the gener-
ator C is started; after it has reached
its proper voltage and the switch 15 is
opened, the switches 1 1 and 10 are closed.

Undercutting Commutator

Mica and Removing

Bad Spots

By Gordon Fox

The commutator is the cause of more
than 75 per cent, of the troubles with
direct-current motors. The most usual
complaint is excessive sparking, result-
ing in rapid brush wear and blackening
and heating of the commutator, possibly
causing the solder in the risers to melt
and become dislodged.

It is impossible to obtain satisfactory
commutation on some motors. Often the
sparking is just sufficient to pit the cop-
per, cause high mica and start the com-
mutator on its downward way. When
it is impossible to prevent all sparking,

Shunt Fields

to cure rough commutators very often
and has found it an excellent expedient.
Commutators often give trouble due
to excessive heating, short-circuits be-
tween the bars and grounds. In many
instances such troubles are due to de-
terioration of the mica by oil. There is
often a leakage of oil along the shaft
from the bearings and the oil creeps up
onto the commutator, soaks into the mica
and destroys its insulating qualities. The
current then leaks through from bar to
bar and causes excessive heating and
possibly short-circuits. Sometimes the
mica rings break down, producing a
ground. Special care should be exercised
to keep the commutator free from oil.
Where there is leakage a leather washer,
held against the inner end of the bear-
ing housing by a sheet-iron washer of

itO- Volt Generator

llO-Volt Generator leo-Volt Generator iS*^ >^ iS«>

Fic. 2. Wiring Diagram and Connections at Back of Switchboard

If the generator A is to carry the load,
the balancer set is first thrown in, and
then the generator; after it has reached
its proper voltage, the generators B and
C are cut out.

A storage-battery plant, said to be the
largest single-battery plant of its kind in
the world, will be erected by the Con-
solidated Gas, Electric Light and Power
Company, of Baltimore, as soon as a
building now being constructed for it is
finished. The building will adjoin the
largest direct-current substation of the
company, and will cost about $50,000,
while the entire cost of the plant will
approximate $300,000. The storage bat-
tery will be of sufficient size to provide
for the peak load in the entire business
district for nearly half an hour should
an accident occur at the time of maximum
consumption.

By developing the unused water
powers, the New York Water Supply
Commission estimates that New York
would derive a net annual income of
57,000,000 from leases granted to small
power plants and machine shops.

even with the motor in good condition,
it is often possible to reduce its destruc-
tive effect by slightly undercutting the
mica. Various methods have been used
for doing this. An excellent method is
to "plane" the mica off with a 6-inch
three-cornered file; one with consider-
able belly and a decided taper toward
the end is preferable. This is broken off
about an inch from the end and the new
end is ground square on an emery wheel,
care being taken not to mark the sides.
The commutator is first trued up and
smoothed by turning or sandpapering;
the mica is then cut down by starting
the belly of the file at the outer end of
the commutator and working toward the
risers, using the groundoff end of the
file as a sort of plow. The belly of the
file follows in the groove cut and keeps
the tool on the mica. A little practice
will enable one to undercut the mica of
a commutator by this means in a sur-
prisingly short time. The groove is not
deep like that cut by a hack saw and is
not as troublesome in the way of collect-
ing dirt. After the mica is undercut the
commutator is again smoothed and
cleaned. The writer has used this means

slightly larger inside diameter fastened
to the housing with screws, will prevent
suction of oil and keep it from creeping
along the shaft from the bearing.

When it is found that the mica seg-
ments have been rotted in spots, all
blackened mica should be scraped or
dug out with a broken hack-saw blade
with the set of the teeth ground off. The
void should be filled with a paste con-
sisting of pow-dered mica (two parts),
plaster of paris (one part) and enough
shellac to make a thick paste. The cop-
per around the patch is then heated
slightly with a torch and the paste al-
lowed to harden. This will require but
a short time. The surface of the com-
mutator is then smoothed over and the
machine is ready to run. If properly
applied, a patch of this kind will not
come out.

The keynote to success in caring for
direct-current motors is to anticipate
trouble and take proper steps to prevent
it before the commutators begin to de-
teriorate. After they once start to cutting
or roughing they get worse and worse
so rapidly that it is almost impossible to
stop it except by turning down.

August 29, 1911

POWER

327

CORRESPONDENCE

Isolated Plant Operating Costs

On page 179 of the issue of August 1
is a letter from Henry D. Jackson, dis-
cussing the item of profit on investment
used in my article on Mr. Rushmore's
operating costs in the issue of June 27.
Mr. Jackson bases his contention, that
this Item of profit should not be in-
cluded, on the conditions existing in a
manufacturing plant. Following out his
line of thought, a manufacturer would
figure his selling price as being the total
cost of production in the shop plus an
overhead charge to cover depreciation,
interest, taxes, etc., plus a further charge
covering the cost of sales and profit.
He would not departmentalize his manu-
facturing establishment, but would treat
it as a complete and well balanced fac-
tory, operating within itself every in-
dividual treatment or process necessary-
in the complete manufacture of its pro-
duct. If any of these individual pro-
esses were left out, Mr. Jackson fears
that the factory would be unbalanced
and not satisfactory.

The development of the large manu-
facturing concerns of the country in the
last five to ten years does not bear out
this line of argument. Ten years ago, or
even more recently, the majority of the
larger manufacturing plants were op-
erated each as a unit, the total invest-
ment being lumped in one sum and the
overhead charges being made the same
all over the factor^'. This left the man-
ager of a factory in absolute ignorance
as to where the plant was making money
and where it was losing it, and it gradual-
ly forced the owners to the division of
their plants into departments. As a re-
sult, the management of a plant is in a
position to determine absolutely which
class of manufacture it is most advisable
to develop, and this knowledge has been
used to excellent advantage.

Referring to the question of the heat-
ing plant cited hy Mr. Jackson, such a
plant, or, rather, some means of heating
the buildings, is necessary. The capital
invested for this purpose, however,
forms a portion of the capital stock of
the company. If the business is suc-
cessful, it must pay a dividend on this
stock, and, therefore, must pay a dividend
on the amount invested in the heating
plant. Since the heating plant is not a
producing department, this dividend must
be paid by some other department. If
the company, for example, is paying 7
per cent, dividends and heat can be ob-
tained from an outside concern for a
price equal to the operating cost of pro-
ducing heat in the heating plant, plus
the depreciation, interest, taxes, etc.,
plus a profit of less than 7 per cent, on
the capital invested, then it would be an
economy for the company to buy heat,
as some portion of the proceeds from the

other department which has been pay-
ing the dividend on the capital invested
in the heating plant will now be avail-
able to increase the dividend rate.

I hardly see how Mr. Jackson can
raise the question of whether a manu-
facturer must consider that he should
make a profit on the cost of his build-
ings or the cost of his transmission ap-
paratus. The capital invested for such
purposes forms a portion of his capital
stock on which he must pay dividends.
If the capital invested in this way does
not of itself produce these dividends,
they must be produced by some other
portion of the plant. There are many
factors besides the question of initial
expense that enter into the determination
of whether a manufacturer should rent
or own his buildings, such as convenience
of location, layout to suit special needs
of the manufacturing process, freedom
to make changes and alterations of a
permanent character, etc.

In the editor's comment the point is
made that no certainty exists that the
manufacturer could make a profit on a
given amount of capital by investing it
in some certain part of his business in-
stead of in the power plant. Unless some
department offered such a certainty, it
is equally certain that the business would
not be a paying one, and hence a manu-
facturer probably would not have any
available capital to invest in his power
plant or anywhere else. If such capital
is available, it is prima facie evidence
that there is some department which will
earn a profit on such additional capital
available for investment.

The editor also points out the fact
that the interest on any investment put
in a power plant goes on, whether the
power plant be operated or not. This is
one of the strongest reasons against
the installation of an isolated power
plant. The histor>' of the development
of all classes of business has been that
the selling price of the product of any
particular class of business decreases as
improvements in the art increase. An
isolated plant today may show a profit
over the cost of power from the cen-
tral station. Five years from today the
central station would in all probability
be in a position to supply power cheaper
than the isolated plant, but the manu-
facturer is already saddled with a large
investment in his plant which must be
depreciated, and on which interest and
other charges must be paid. This amount
may be so large that he will not be able
to avail himself of the advantages of-
fered to the central-station plant.

A competitor starting in business under
the new conditions is able to take ad-
vantage of the central-station proposition
and thereby undersell his opponent who
isolated his power plant five years be-
fore. The new competitor is able to
extend his business more readily, with
less delay, and with a smaller capital in-

crease than the older manufacturer. In
short, with an isolated plant once in-
stalled, the owner thereof is compelled
in a large degree to follow out a certain
line of action and is not left free to
exercise his judgment in choosing the
course which may be most economical
for him.

R. D. De Wolf.

Rochester, N. Y.

[Mr. De Wolf's reference to our com-
ment following Mr. Jackson's letter is
not quite accurate. We did not say there
was no certainty of making "a profit"
on money invested in the manufacturer's
business; we said there was no cer-
tainty that the money represented by the
power-plant investment would, if in-
vested in some other department of the
plant, earn the profit estimated by the
central -Stat ion solicitor. — Editor.]

Mr. Crane's Switchboard

In the issue of August I, G. H. Mc-
Kelway and A. L. Harvey offer some
criticisms of the switchboard which I
described in the issue of June 20, which
lead me to explain that this board was
not meant to take the place of the usual
panel switchboard in a powder station
of such size that an attendant is al-
ways at hand and gives considerable
attention to the looks and care of the
board; it is suitable and much prefer-
able, however, in small plants where no
attendant is employed.

My occupation takes me into a large
number of manufacturing plants and I
have seen many of the slate and marble
switchboards located near walls, with
the space behind the board filled with
all sorts of scrap and used as a general
receptacle for all kinds of material. With
a board of the construction I described,
everything is open and no space is of-
fered to serve as a refuse can.

Mr. McKelway misunderstood the last
paragraph of my article; this was in-
tended to mean that the price was for
the installation complete without the
motors; in other words, for supplying the
switchboard and the wiring for the
motors.

If preferred, and as undoubtedly re-
quired by the underwriters in the East,
it is possible to make the cross pieces
of pipe instead of hard wood (treated).

Referring to the relative costs of the
two kinds of switchboard for the plant
mentioned, the figure on the switchboard
alone, using slate panels, was S250 and
the cost of the wiring for the motors
and the skeleton board described was
$240.

This type of construction is being used
for several other purposes and is now
recommended by the larger electric com-
panies for mounting starting compen-
sators, oil switches and such apparatus
where they used to recommend slate
panels.

Duluth, Minn. J. B. Crane.

POWER

August 29, 1911

Gasifying Crude Oil
By H. a. Grine

There are practically three general
methods of gasifying crude oil, namely,
destructive distillation, destructive dis-
tillation and partial combustion com-
bined, and partial combustion. In the
first method the oil contained in iron or
fireclay pipes or retorts is gasified by
applying heat to the outside of the pipes
or retorts and causing destructive dis-
tillation of the oil, or by heating up
chambers by blasting and alternately
making gas by discontinuing the air of
the blast and spraying in oil and oil and
steam. Ir. some cases a small amount
of air or steam is admitted with the oil.
These methods retain the objectionable
features of requiring a frequent burn-
i'lg out of carbon, and forming a gas
com^posed mostly of hydrocarbons and
therefore not well suited to gas engines.

The second method is a step forward.
It is usually carried out in shells similar
to those used in domestic gas plants or
in specially designed shells or gen-
erators. It consists in injecting or dis-
tributing oil within a closed shell or gen-
erator in the presence of sufficient air
to cause partial combustion of part of
the oil and destructive distillation of the
remainder. Usually sufficient partial
combustion is permitted to maintain a
temperature high enough to make the
process continuo'is. Owing, however,
to the destructive distillation and car-
bonization of a large part of the oil,
sufficient lampblack is formed to gradual-
ly stop up the outlet pipes and gen-
erator. This difficulty has been met to
some extent by burning out the generator
while running on gas from a gas nolder,
or by providing duplicate units and
changing at stated intervals. Gas made
by this method still retains a relatively
large percentage of hydrogen and hydro-
carbon gases, and is not considered by
gas-producer engineers to be as well
adapted to gas engines as the gases
made by coal-gas producers, which con-
tain a higher percentage of the slow-
burning carbon monoxide gas. Attempts
have been made so to proportion the air
as to burn up the lampblack as fast as
it is formed, but none has succeeded
so far, owing probably to the fact that
the gases formed by destructive distilla-
tion are more readily combustible than
the lampblack and take up the oxygen
before the lampblack can be gasified.
The third method is the most advanced

as the oil undergoes almost complete
dissociation; the hydrocarbons are broken
down into small percentages of methane
and hydrogen and the carbon is oxidized
chiefly to carbon monoxide. The pro-
portions of carbon monoxide, methane
and hydrogen in gases formed by this
method are almost ideal for gas-engine
work. The gas is easily ignited but has
not the snappy sharp explosion so char-
acteristic of gas containing large per-
centages of hydrocarbon gases and
hydrogen, with little carbon monoxide.

In the past few years certain engi-
neers have been investigating and de-
veloping the crude-oil gas producer
along lines of proved practice in the
gasification of bituminous coals, and
there has been progress made which
seems to assure the success of the crude-
oil gas producer, and promises a very low-
cost power-developing system for sec-
tions where oil fuels of any grade are
the most readily available. A gas pro-
ducer has recently been constructed for
use with crude oils and in commercial
tests has demonstrated its merits. A
100-horsepower plant installed about the
first of this year is in daily operation
24 hours per day, furnishing gas to an .
engine driving an air compressor and a
duplex water pump. The unit has only
one gas generator, requires no rotary or
other mechanical scrubber, and the
amonnt of carbon byproduct is negligible.
The operation is continuous, and the
generator requires no burning out and
no more attention than a boiler plant.

The system has a great advantage in
the fact that it secures a greater decom-
position of the hydrocarbons of the oil
and forms a gas containing a larger per-
centage of carbon monoxide than is pro-
duced in other oil systems. An average
analysis of gas made is as follows:

CO l.T 0 per cent.

H, 6.1 per cent .

CH, ,5.3 per cent.

CiiHsu 1 . 1 per cent.

CO, 6. 7 per cent.

Na 6R.G per cent.

O, 0.2 per cent .

The heat value is 148.4 B.t.u. per
cubic foot.

A Steam Engineer's Experi-
ence with Gas Power
By S. G. Rose

As the question of putting gas-power
plants in charge of steam engineers has
received considerable attention recently,
the following remarks may be of interest
to those confronted by that problem:

I am operating a gas-power plant con-
sisting of two engines and two suction
producers, with the usual auxiliaries,
such as a small engine for pumping com-
pressed air to start, pumps, etc. Before
taking charge of this plant I had been
operating steam engines and boilers. I
started in as a boy working in a loco-
motive roundhouse and went to firing as
soon as I was old enough. Eventually I
got to be an engineer. I started in this
country as a stationary fireman and a lit-
tle later became an engineer. When my
employers enlarged their plant and put
in gas engines I was selected to run
them. I took a liking to the gas engine
from the start and put in a good many
hours studying it and the principles on
which it works. Except for a few blund-
ers on the start I have not had any
trouble with the engines; they have not
had a 5-minute compulsory shutdown
so far this year.

I do not see any reason why any steam
engineer worthy of the name could not
do exactly what I have. The gas engine
and producer only require a little even-
ing study and a little closer attention
than a steam plant when running. There
have been some good articles published
in this paper by Cecil Poole on the
suction-gas producer and I think it will
pay steam engineers to study them.

Referring to the amount of attention
required by a gas-power plant, I fail to
see how C. O. Hamilton* could expect a
man to run a 200-horsepower suction-gas
plant with only three hours' attention per
day, and I think it would be better for
anyone who has the welfare of the gas
engine at heart not to make such asser-
tions. It causes a lot of trouble between
owners and engineers w-hen the owners
have been led to believe that such econ-
omy in labor is possible with the suc-
tion-gas producer and engine. I find that
the more attention I give my plant, within
reasonable limits, the better are the re-
sults.

In a plant of 200 horsepower, on full
load, I should expect about 2500 pounds

•"Steam Engineers for Gas Power Plants" ;
May 16 issue of Pownn. >

August 29, 1911

POWER

of pea coal per day and if there is not
a storage bin overhead it would have to
be put in scuttles holding about 45
pounds; that means about 55 scuttles per
day. That alone would occupy about 1 ■ ^
hours of a man's time. Sometimes the
coal has to be screened and it may have
to be wheeled in from a shed; these op-
erations, of course, add to the time re-
quired. Then, again, some producers re-
quire poking before starting and clean-
ing out at noon and night. If they are
without shaking grates, like these I am
operating, this takes up some time and
when they are running they also require
a certain amount of attention, such as
poking the fire over the bars occasionally,
poking down from the top of the gen-
erator and keeping an eye on the water
going to the vaporizer and the scrubber.
Then there are ashes to be removed and
the producer room to be kept clean; the
fine ash from the generators makes quite
a mess over everything. The excelsior
or sawdust and coke in the scrubbers
should be changed occasionally and the
gas passages must be kept free from dust
and other obstructions; the blowoff valve
gets dirty ver\' quickly and if there are
any gate or other valves they should be
taken apart occasionally or the operator
will find them stuck when he wants to
use them. Finally, the producers should
be cleaned out entirely at intervals of
one to three months, according to local
conditions.

So far, only the producer end has been
considered. Coming to the engine equip-
ment, I find that it does not pay to go
very far away from the engine room. I
would rather leave a steam engine run-
ning alone than a producer gas engine;
because it is impossible to get the same
quality of gas always and if an engine
should backfire or preignite someone
should be on hand to remedy the
trouble.

Gas-engine bearings and lubrication
require far more attention than those of
steam engines and it pays to take a
look at the lubricators pretty often. A
hot bearing on a 200-horsepower gas
engine entails more trouble than one on
a steam engine of the same output be-
cause the bearings are much heavier.
The valves should be taken out quite
frequently, as producer gas is rather hard
on them, and it takes quite a bit of time
and energy to take out and grind a
water-cooled balanced exhaust valve; the
smaller valves, such as gas and mixing
valves, should be cleaned every week;
the engine room should be kept clean and
the brasswork, which soon gets tarnished,
needs occasional polishing; besides all
this, there is a certain amount of petty
routine work which must be done around
a plant.

In my plant I have to look after three
large clutches, a heating boiler, a 775-
kilowatt generator and two motors
and pumps and it keeps me and a helper

busy regularly, with an occasional Sun-
day in addition.

Of course, the amount of attention re-
quired depends greatly on the equipment,
but I think that if one man ran a plant
of 100 to 150 horsepower he would be
doing well and that it would be worth at
least his wages to his employer to have
the man right at hand to prevent avoid-
able stoppages and accidents to the equip-
ment, leaving out of consideration the
advantage of not taking his mind off his
plant by having him do other work.

A Disastrous Dose of Water

By M. W. Utz

The accompanying sketch illustrates
the damage to a two-cylinder duplex
horizontal gas engine of about 85 horse-
power, which occurred in a small elec-
tric-light plant and was caused by very
unusual circumstances.

The air-inlet pipe to the engine runs
along under the floor of the room to
the outside of the building and takes air
from a small concrete pit under the
steps to the building.

The city water works is combined
with this plant, and the water is taken
from deep wells by an air lift and dis-
charged into a large cistern just out-
side the plant, whence it is pumped

Damage Done by Water

into the mains by reciprocating steam
pumps. The engineer allowed the water
to get so high in this cistern that it
overflowed, flooding the pit where the
gas engine takes air, and causing the
engine to take water instead of air; the
cylinders filled with water, which wrecked
them as here indicated.

One cylinder head was blown out,
breaking along a circle just inside the
studbolts, and the other head broke
about halfway across and tore out part
of the cylinder barrel. All the studs
were "started," some were sheared off,
and the threads were stripped off some.
The cylinder on the left had to be re-
placed by a new one, of course.

The accident happened just as the
motor load went off at noon, leaving
the engine running almost idle. No one
was hurt, but the engineer had just
walked past the engine and over to the
opposite side of the room to shut off the
air compressor, missing being caught in
the wreck by a few seconds.

Of course, accidents will happen in
almost any power plant, but isn't it poor
judgment to have a gas engine fake
air from an underground pit?

Points in the Operation of

Suction Producer Plants

By N. E. Woolman

The readers of the Gas Power De-
partment no doubt have experienced
trouble in starting suction gas-producer
engines and have said things that would
not look very well in print, in the end,
however, finding a good reason for the
trouble.

One of the most common troubles is
water in the gas, which short-circuits
the igniter. The cause is due, princi-
pally, to blowing hot gas through a wet
scrubber, but it might be caused by the
hot gas passing over the water in the
seal. It is very misleading at times, be-
cause the igniter will test clear when
the engine is standing, but the incoming
charge will carry enough moisture to
short-circuit it upon starting.

In a great many cases trouble will
be experienced with the engine flooding
with gas when the air is taken through
a long pipe from the outside of the
building; this is quite common with an
extremely hot fire, because the draft in
the producer "pulls" the gas over more
rapidly than the corresponding volume
of air can be sucked through the long
pipe. If the engine has to depend upon
only one or two revolutions to take its
charge and start, some difficulty will be
experienced unless the air pipe is discon-
nected. If the engine is equipped with
an automatic air starter, this trouble will
seldom occur if the compressed-air tanks
have capacity enough to keep the engine
going long enough to start the column
of air in the supply pipe.

It often occurs that trouble will be
had from too hot a fire or abnormally
rich gas if there is appreciable resist-
ance in the air intake; with a hot fire
there is very little resistance to the gas
flow. A graduated dial on the gas valve
is handy in such cases; with a little
practice one can adjust it and never lose
a start.

A great deal can be gained in economy
by having the fire as nearly as possible at
the right temperature at the start. If the
fire is too hot at the start it will be im-
practicable to feed enough steam to it to
cool it down for several hours on ac-
count of preignition and back firing at
the engine, and during that time hard
clinkers will form. The extremely hot
part of the fuel bed at that time will
probably not exceed 18 inches in depth
and will be sticky and offer a good deal
of resistance to the air passing through.
The path of least resistance is next to
the firebrick, where the air and steam
will harden the clinkers that have al-
ready formed.

It is a known fact that if fakes con-
siderable blowing to vary the fire beyond
a certain depth. If an engine were started
with the fire not sufficiently hot, the

330

POWER

August 29, 1911

steam would have to be held off until
the engine had "blown" it hot by suc-
tion; then when the steam was turned on
the excessive draft from the engine
would pull holes through the fire and
weaken the gas to the extent that it
would be difficult to carry the load. In
that case it would take several hours
to get the fire in good condition and dur-
ing that time there would be an ap-
preciable waste of fuel and power.

It is important to the economical and
successful operation of a suction gas
plant to admit steam to the fire im-
mediately after staning, because if the
steam is withheld, the engine will "pull"
the fire to an excessive heat and waste
the fuel. If the steam is not carefully
regulated to the fire in that condition,
there will be a good deal of trouble in
the way of back firing and premature
ignition at the engine, especially if the
engine is well loaded and carrying full
comprassion; the chances are that the
trouble will continue during the run.

A superimposed vaporizer, or one that
utilizes the heat from the hot gas, is not
very satisfactory in most cases, more ea
pecially when starting up, because it
takes too long to get steam ; the steam
has a tendency to work the fire upward
and the nearer it is to the vaporizer the
more steam will be produced, regardless
of the load. It is not at all easy to au-
tomatically regulate the water and steam
to the varying temperature and load con-
ditions, but the most successful form of
vaporizer is one that automatically regu-
lates the supply of water to the vary-
ing load.

One of the chief causes for so many
failures in suction gas-engine installa-
tions is carrying too high compression;
with very high compression an engine
will not stand the varying quality of suc-
tion gas. There are large engines carry-
ing from 170 to 200 pounds compres-
sion pressure and giving good results,
but it is owing principally to the scaveng-
ing effect due to proper timing of the
valves. Judging from all reports, an en-
gine using about 140 pounds compres-
sion gives the best all-round results, in
view of the fact that it takes a larger
bore and stroke to produce the same
horsepower.

Why the Gas Supply Failed

By H. H. Daniel

A pumper from a nearby oil lease re-
cently called on me to examine his en-
gine, as he and his son had been "kick-
ing" it all day and were unable to get
any response. This engine was a 15-
horsepower Lwo-stroke cycle machine
supplied through a gas regulator which
had a diaphragm across the center; at-
tached to this was a plunger which ex-
tended through the top and was linked
ttp to a stop cock in the main line, as

show-n in the sketch. When the gas pres-
sure was above normal, the diaphragm
pushed up the plunger and thereby shut
off the supply of gas, and vice versa.

Now one thing I always like to know,
before doing much to a gas engine, is
whether I have got the wherewithal
to make her go if she is in shape other-
wise. So the first thing I did in this
case was to find the regulator, push
down on the plunger, and — the trouble
was located. The plunger was at its
topmost position with the stop cock
closed, and the link levers were stuck
tight. I put some oil on the joints,
worked the plunger up and down a few

The Seat of the Trouble

times, turned on the gas, put my "strong
right foot" to the flywheel and presto'
the engine ran perfectly. What the
pumper said was unfit for publication.

This engine had been shut down for
a day and the gas pressure came on
stronger than usual and forced the levers
of the regulator up a little higher than
they had ever been before, to a position
where the pivots were not entirely free,
and they stuck in that position.

Decarbonizing Internal-Com-
bustion Engines

Consul Augustus E. Ingram, of Brad-
ford, Eng., reports a British invention of
interest to users of automobiles and
motor cycles which has recently been
brought out for the purpose of remov-
ing carbon deposits from the cylinders of
internal-combustion engines. The amount
of carbon deposit which adheres to the
cylinder walls, piston heads and valves
is considerable, particularly in air-cooled
engines. With this invention it is not
necessary to dismantle the engine or dis-
turb any of the connections, and it is
claimed that the decarbonizing is done
quickly at trifling expense. The apparatus
consists of a cylinder of pure oxygen, to
which is fitted a pressure-reducing valve
with a flexible tube and blowpipe con-
nected, and is started by a small petrol
hand lamp with a long nozzle and wick.
The process, after the valve caps have
been removed, consists of inserting the
oxygen blowpipe and the lamp nozzle
through the openings into the cylinder
head and allowing the flame to impinge
on the carbon, which immediately be-
comes incandescent and comes away in
the form of light sparks. It is considered

advantageous to warm up the engine prior
to commencing operations, this having a
tendency to soften the carbon slightly,
making removal easier.

LETTER

Lightening Pistons Improves
Flexibility and Accelera-
tion

The engine on a pleasure omnibus
suffered from lack of "life" and took a
long time to accelerate, although in other
respects, such as steady pulling and
power, it was all right. Everything was
tried, from retiming the valves to re-
placing the carbureter with other types
for trial, but the engine did not show
any improvement at all.

Finally the maker's man was sent for
and after going over everything again
he took the pistons out, chucked them
in a lathe and took a fairly deep cut
around the inside of the skirts, below
the gudgeon-pin bosses. When he had
removed some metal from each piston,
he weighed them and then turned three
of them down to the exact weight of
the lightest. They were then replaced in
the engine, which showed at once a re-
markable improvement, although it was
still rather slow in accelerating. How-
ever, it was not considered advisable to
remove any more metal, so the engine
was left at that.

An alternative method would have

been to drill holes in the skirts of the

pistons below the gudgeon pins, but this

might have weakened the pistons unduly.

John S. Leese.

Manchester, Eng.

Brown, Boveri & Co., of Baden,
Switzerland, have taken out patents on
that type of turbine which comprises an
impulse section, followed by several re-
action sections. It is customary in such
turbines to make the cross-sectional area
of the reaction sections adequate for
the flow of steam when all of the im- •
pulse nozzles are open. Under light
loads when a small amount of steam is
flowing the expansion is excessive, re-
sulting in an impairment of the efR
ciency. The new turbine is arranged so
that a reaction section is cut out
simultaneously with the closing of each
of the high-pressure nozzles.

Trouble is sometimes experienced in
making asbestos covering stick to pipes
and cylinder heads. When putting on
such a covering, first coat the surface
with silicate of soda, sometimes called
liquid glass, and before it has time to
dr\' apply dn,* asbestos as thickly as
possible by handfuls. The silicate will
hold enough of the asbestos to ser\'e as
an anchor for the following coats to be
applied in the same way.

August 29, 1911

POWER

331

Approximate Heat Value of
Coal

Some of the readers of Power may
be interested in a method used in a
small light and power plant for finding
the approximate heat value of the coal
used. A daily log was kept in which
was recorded the steam pressure, steam
temperature, vacuum, etc., and from this
log calculations were made as to the
coal burned per kilowatt-hour, heat value
of the coal, etc.

Nine tons of coal were used per day,
and on an average 8.5 pounds of water
were evaporated for each pound of coal
burned. Before the feed water entered
the boiler its temperature was raised to
200 degrees Fahrenheit by means of a
feed-water heater.

From the daily log the average steam
pressure was found to be about 150
pounds gage and the average steam tem-
perature was about 450 degrees, show-
ing that the steam was superheated.

Using Peabody's steam tables the tem-
perature of saturated steam at a pres-
sure of 150 pounds gage, or 165 pounds
absolute, is 365.09 degrees, showing that
the steam was superheated 84.91 de-
grees.

Since the entering feed water is 200
degrees and the temperature of saturated
steam corresponding to a pressure of 165
pounds absolute is 365.88 degrees, then
the number of heat units required to
raise each pound of water through the
required temperature range is

365.09 — 200 = 165.09 B.t.u.

The amount of heat required to convert
each pound of water at this temperature
into steam at the same temperature is
found from the steam tables to be 856.8
B.t.u. Therefore the heat required to
raise one pound of water from 200 to
365.09 degrees and to convert it into
steam at this temperature is

165.09 -f 856.8 ^ 1021.89 B.t.u.

Since the steam is superheated 84.91
degrees, the heat required to superheat
this amount must be added to the above
amount. The specific heat of superheated
steam may be taken as 0.48; therefore,
the heat required to superheat each
pound of steam 84.91 degrees will be

84.91 / 0.48 40.75 B.t.u.
The total heat units required for each
pound of water evaporated and super-
heated will be

1021.89 + 40.75 = 1062.64 B.t.u.

As 8.5 pounds of water are evaporated
per pound of coal the number of heat

units that are utilized by the boiler per
pound of coal are

1062.64 X 8.5 = 9032.44 B.t.u.

This would be the heat value of the
coal per pound if the boiler had 100 per
cent, efficiency which, of course, in prac-
tice it has not. The efficiency of the
particular boiler in question was about
65 per cent., therefore, the actual heat
value of the coal per pound would be

9032.44 -H 0.65 - 13,900 B.t.u.
nearly.

This method of finding the heat value
of coal is, of course, only approximate,
since it depends on the efficiency of the
boiler, but comparison of different fuels
under similar conditions can be made
very accurately and in practice this meth-
od is often used.

T. W. HOLLOWAY.

Scranton, Penn.

Oil Filtering System

A simple oiling arrangement that I
have used for over two years is shown
in the accompanying illustration. A hole

gine. Then I set up a J4 -horsepower
motor D and a small pump C to pump
the oil out of this tank and get it into a
tank F of the same size, placed as near
the ceiling as possible. A 2-inch pipe G
was connected to the bottom of this tank
and ran down to within a few feet of the
floor where it was reduced to 1 inch and
a 1-inch valve A' connected in the pipe.
This pipe entered the bottom of an up-
right 6-inch pipe H that was 10 feet
high (the higher the better). A 1-inch
pipe and valve M is used for a drain to
the sewer.

The oil and water are pumped from
the tank B up through the pipe E into
the tank F, and flow through the pipe
G to the bottom of the standpipe H,
which is filled with water to about 2 feet
from the top. The oil rises through
the water and after filtering runs out
near the top through the pipe / into a
smaller tank } and then flows to the oil
cups on the engines through the pipe K.
The pipe / must be about 12 inches be-
low the bottom of the tank F or the oil
will not rise high enough in the pipe H
to feed into the tank /.

The tank / and standpipe H are each
fitted with a gage glass to show the
position of the oil. Water should show
in the bottom of the glass in the stand-
pipe H. If it gets too high the valve N
should be closed and the valve M opened
a few seconds. This will let the dirt
and sediment run to the sewer and keep
the water clean in the standpipe H, so
that the oil will filter freely.

y/////////////////////////Ay/^^^^^^

was dug below the engine large enough
to hold a 2 and 2 by 4- foot tank B which
was to receive all oil drips from the en-

The pipe O, on top of the standpipe
W, is for a vent and also to keep the
standpipe W from overflowing. The sys-

332

POWER

August 29, 1911

tern holds about one barrel of oil and
feeds two engines with a steady stream
on the bearings. Once a month the tanks
B and / are cleaned; otherwise the sys-
tem does not require any attention. I
plan to keep the valve A^ open just
enough to feed oil into the tank / slight-
ly faster than the engines use it. By
looking at the feeds and gage glasses
once an hour, trouble is avoided. I ran
the standpipe H up beside the exhaust
pipe, as the oil filters better when kept
warm. One barrel of oil is used about
every 10 days. There are no screens or
waste to clog up and the dirtiest oil can
be filtered.

The tanks, motor and pump were
found in a corner so that the system
cost but a few fittings.

P. B. Hartford.

New York City.

Hot Bearings

Regarding cooling hot bearings, I have
used water, graphite and sulphur with
and without oil or grease and have had
better success with sulphur in cooling
very hot bearings than with anything
else.

I was oiling on a steamboat once
where the crank pins, wristpins and main
bearings were ah lubricated with hand-
compression grease cups. One of the
crank pins got so hot at one time that
the cooling water in striking it sent up
clouds of steam. When I came on watch
the engines were running at reduced
speed in an endeavor to cool the pin.

The chief suggested stopping to loosen
up the brasses, but the weather was
rough and we were on a dangerous coast.
I got some sulphur and mixed it with
the grease and fed it through the grease
cup to the bearing. In less than half
an hour we were running full speed
again.

If a bearing is very hot and sulphur
can be fed into it, either in the oil or
through a grease cup, it will surely pre-
vent seizing, as it will melt at a much
lower temperature than the babbitt of
the bearing and will form a film around
the bearing and reduce the friction.

Graphite will pack in the bearing and
unless it can be forced out it may pre-
vent oil from getting to the bearing. Cold
water is very apt to make the bearing
shrink and seize the shaft. If water is
the only cooling agent at hand, it should
not be applied directly to the journal
boxes but to the shaft or exposed part
of the bearing; these parts should be
cooled before cooling the box. This will
cause the shaft or pin to shrink slightly
and will give the oil or grease a chance
to get in around the bearing. Then force
a little graphite or sulphur in with the
lubricant and the engine need not be
stopped.

A. A. Blanchard.

Oak Harbor, O.

Automatic Control of Cir-
culating Water

When the 500-kilowatt steam turbine
was installed it was arranged to drive
the circulating pump by an electric
motor. Aside from the questions of econ-
omy involved, other serious faults were
soon revealed, not the least of which
was the motor's subservience to the law
of synchronism with its source of power.
This resulted in the delivery of the least
amount of water by the circulating
pump when the most was needed, this
peculiarity, however, had been antici-
pated and partially allowed for by the
installation of a pump which was cap-
able of delivering sufficient cooling water
while the turbine operated at overload
speeds.

But as the turbine was subject to very
variable loads, the pump at periods of
light load delivered considerably more
water than was required; which resulted
not only in the useless expenditure of
power but also in the loss of heat units
in the condensate, which at this station
is returned into the boilers.

hand enough to allow the passage of
sufficient cooling water to maintain a
good vacuum while the load on the tur-
bine creates a pressure of not over 20
pounds in the first stage. When this is
exceeded, the pressure will overcome the
purchase and gravity of the balancing
weight B on the long lever of the regu-
lator; and the regulating valve A is
opened by means of the lever D, rod E,
arm F, rope G, sheaves H and K. rope
L, sheave M and weights N.

The amount of regulation is control-
lable by shifting the hook of the rope G
on the upright piece of the arm F. As
there is often a vacuum in the first stage
of the turbine, it is necessary to guard
against undue breathing of the diaphragm
of the regulator by fitting a perforated
plate to support it.

C. Hughes.

Saxonville. Mass.

Dilapidated Boiler Conditions

The boiler battery in a certain plant
consisted of two 72-inch return-tubular
boilers in one setting.

c§

A

Valve Operated by Means of a Da.mper Regulator

The pressure in the first stage of the
machine varies according to the drag on
the turbine and the idea was conceived
of communicating the pressure of this
first stage to the pressure chamber of
an old damper regulator, which by means
of suitable levers and pulleys was made
to control the regulating valve on the
circulating-water line between the pump
and the condenser. The manner in
which this was accomplished is shown
in the accompanying illustration.

The regulating valve A is opened by

Boiler No. 1 w-as equipped with a low-
water alarm, which had been installed
by drilling a hole through the shell be-
tween the manhole and the steam dome.
This pipe ran down to within 'u inch of
the top row of tubes, and before the
whistle blew the water would be below
the safet" point.

This side of the setting had settled
2'j inches, so that when one gage of
water showed on No. 1 boiler, it was out
of sight in the water glass of No. 2
boiler.

August 29, 1911

POWER

333

Both boilers were connected with a
cross dome, and fitted with a ball and
lever safety valve which was set so close
to the roof, which had also settled, that
one of the rafters rested on the lever;
100 pounds gage pressure was carried.

When I went into No. 1 boiler I found
two braces broken on the back end. which
had a bulge of 1 inch.

J. A. McQueen.

Cheboygan. A\ich.

Required Nene

In a certain power plant there were
10 steam engines working in pairs with
one flywheel, each set driving a pair of
generators with a load of from 500 to
800 amperes.

One morning the switchboard tender
called for another machine, so my
partner and I got a pair of engines ready
but there was not enough load for the
two machines. I opened my throttle wide,
which required about 12 or 14 turns,
while my partner opened up the other
throttle two or three turns. While wait-
ing for the load to come on I saw the
rope drive standing. The switchboard
tender cut out the machine suddenly
and the engines began to run away with
full steam pressure and no load. ,

My partner had no trouble in shutting
down his engine, but I did not take time
to close the throttle. Instead I caught
hold of the blocks and kept them up so
that the hooks would not catch on and
open the steam valves. I held on until
the engineer closed the throttle — which
seemed to me like a lifetime — standing
in front of the swiftly revolving wheel
while the rope was tearing the wooden
floor and sending pieces of boards over
my head and at my feet. If 1 had
stopped to close the throttle the engine
would have gained too much headway
and an exploded flywheel would have
resulted.

P. J. McEn.\ney.

Chicago. 111.

Receiver Conden.sation

Several days ago I visited a friend who
is operating an 18 and 38 by 30-inch
vertical cross-compound engine, which
runs at a speed of 15.5 revolutions per
minute with 150 pounds gage pressure
and carries about 400 kilowatts. He
called my attention to a !.;-inch stream
of water which was escaping from an
automatic valve from the receiver. He
said it flowed continually while the en-
gine was running and that he was at a
loss to know why there was so much
condensation.

The receiver is well covered and there
are live-steam pipe coils in it to act as a
superheater.

At present a portion of the main steam
line is not covered, but there are sep-
arators that would surely handle all the
condensation before it reached the high-
pressure cylinder.

Can any reader who has had exper-
ience with compound engines give a rea-
son for so much condensation?

William H. Swope.

Tiffin, O.

Scale in Suction Pipe

At the plant where I am employed a
part of the equipment consists of an
open feed-water heater made similar to
that shown in the sketch. Two lli and
5 by 6-inch duplex feed-water pumps
are used and the compound is fed into the
suction between the heater and the pumps.

When first put in operation the pumps
handled the water at a- temperature of
204 degrees Fahrenheit without giving
any trouble. Two years ago it was
found necessary to put in a ! 4 -inch cold-
water connection, not shown in the
sketch, so that when one of the pumps
started bucking, it was given a little
cold water until it worked smoothly.

Matters, however, kept getting worse
until it was necessary to keep the ^4-
inch valve open all the time with the
water in the heater at 204 degrees Fah-

First the plug in the line was removed
and I expected to see it full of scale,
but it was as free as on the day it was
put in. I began to feel that I was on
the wrong track, but kept at it and
started on the other end. I then found
that the 4-inch suction pipe was almost
full of scale, as shown by the dotted
lines in the accompanying illustration.
From the compound connections to the
heater there was only a V4 inch open-
ing. The pumps now handle the water
at 206 degrees without any trouble.
This would have been the case at all
times had the compound been fed into
the nipple close to the heater.

B. S. Hartley.

Tipton. Cal.

Firing Boilers

A fireman's work, if properly per-
formed, requires considerable skill and
science. He must change his method of
firing ever>' time the quality of the coal
varies and even batches of coal taken
from the same lot have to be handled

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Heater and Scaled SucTtON

renheit. I put new valves in both feed-
water pumps and repacked the water
ends all of which seemed to make them
buck '.vorse 'han ever.

Then 1 removed one side of the heater,
cleaned everything out and put in new
filtering material, but it did no good.
Finally I got a chance to shut down and
got busy on the heater connections; al-
though the water was carried as high in
the heater as it would stand, I had de-
cided that there was not enough head
for the temperature.

differently. A fireman must not only
handle the fire« according to the quality
of the coal, but to suit the boilers as
well.

An engineer can tell a fireman the
best way to manage the fires, but it is
up to the fireman to find out for himself
the better way.

Take all the advice that is given, sift
it down until the meal is found, then
use the best of it.

W. Brown.

Waterford. Conn.

POWER

August 29, 1911

Massachusetts License Laws
and Examiners

In the August 1 issue, Mr. Levy men-
tions a number of questions propounded
to applicants for examination which may
be true and again may not be; that is,
unless the information was obtained
first-hand. It is a trait of human nature
when failing in a certain desired aim to
find plausible excuses and in the case
of failure to pass an examination, quite
often the excuse given is the unreason-
able questions asked.

Mr. Levy speaks about the retubing
of a Babcock & Wilcox boiler and that
no one ever heard of a third-class engi-
neer retubing such a boiler; also that he
worked in eight different plants, some
of them large and uptodate. and none
of them possessed a tube expander. All
the power stations of our local street-
railway service, as well as electric-light-
ing service, are provided with expanders,
and personally some years ago, while
carrying a third-class license, I very
often cut out and put in new tubes; of
course, under the supervision of the
chief engineer.

As to the statement that the examina-
tion fee should be refunded if the ap-
plicant is rejected, this would mean that
some men would be up for examination
every 90 days or as soon as the law
would allow them after the previous ex-
amination.

I have been present a number of times
at the examinations and have failed to
see where really unreasonable questions
were asked. It is true that examinations
are stricter than they have been in
previous years, and some may believe
them a little too strict, but as a whole, the
examiners who have risen from the ranks
are fair-minded and endeavor to do
justice. It is not just to say that there
is a conspiracy against the engineers
and firemen and it is equally unjust to
insinuate that first-class engineers have
conspired to keep their assistants down
because they fear a natural competition
for the higher-priced jobs.

Referring to personal experience, the
plant where I am employed requires a
first assistant with at least a second-
class license providing the chief engi-
neer is on the premises all the time, or
otherwise a first-class license is required
of the assistant. During my seven
years' connection with this plant, a num-
ber of men have procured first-class
licenses who came to the plant with

Comment,
criticism, suggestions
and debate upon various
articles, letters and edit-
orials which have ap,^
peared in previous]
issues

a second- or third-class license. One
among them is now a State inspector,
another has gone to a larger job and a
third is still with us.

I do not believe that the questions
asked applicants for a second- or even a
third-class license will make any of our
uptodate chief engineers gaze dum-
founded, as Mr. Levy states. He also
mentions House bill 310, which was be-
fore the last session of the Legislature,
with the comment that he had a bouquet
handed to him in the shape of this bill,
mentioning that he was already to smile
but found that the right of appeal had
been taken away from him.

Having had considerable to do with
this bill, I may be able to point out a
few incidents which may enable Mr.
Levy to understand the matter more
clearly. House bill 310 was drawn by
a number of men representing various
bodies and was presented to the Legis-
lature. There were a number of hear-
ings given by the mercantile committee
of the Legislature which were generally
only attended by the committee inter-
ested, although the widest publicity was
given as to the date of these hearings.
When the various committees, represent-
ing educational as well as labor organ-
izations in the engineers' field, found that
there was something in the bill which
they did not quite agree upon, these
various committees met at the State
house in Boston a number of times,
some sessions lasting until midnight or
later, endeavoring to the best of their
ability to bring out a bill which would
serve all interests as much as possible.
The result was a perfected bill which
was called Senate bill 470 and which
was returned to the mercantile com-
mittee. This committee gave numerous
hearings, generally noted for the absence
of many men who were but too ready to
immediately criticize the actions of their
committees.

Mr. Levy also cites the Pittsfield
disaster, saying that as long as the pres-
ent situation prevails, such disasters will
continue. One reason whv a board of

three examiners was specified in the new
law to examine men for the higher grade
of licenses was to eliminate the human
equation as much as possible by holding
three men rather than one responsible
for the granting or not granting of a
license. And while there is no appeal
from such an examination the applicant
has the right to again apply after 90
days. This will also tend to eliminate
the so-called personal trick or catch
questions which so many talk about, but
personally I have no knowledge of them.

I would like to add that there is no
better way of getting acquainted with the
Massachusetts license law and its work-
ings than to occasionally visit room 3
of the State house, where this depart-
ment is located, and many prejudices
will disappear when coming in personal
contact with the men composing the de-
partment, and especially so if present at
a few examinations.

Albert S. S.mith.

Boston, Mass.

In the August 1 issue, J. A. Levy makes
a protest against what he terms "the un-
just system existing in Massachusetts."
His view of the present system, how-
ever, is probably not held by more than
a small percentage of the engineers in
that State.

If only a certain set of the "cut-and-
dried" questions were used in examina-
tions, it would be an easy matter for any
person desiring a license to memorize the
answers and be able to answer them sat-
isfactorily. The use of unexpected and
so-called "catch questions" is the exam-
iner's only means of finding whether a
man is really well informed and capable,
or has only been coached and crammed
for the purpose of securing a license.
Just as we may use a yardstick to find
the dimensions of a much smaller object,
so the examiner makes use of questions
which he may not expect to have fully
answered, but which will help him to de-
termine the true measure of the man.

It should be remembered that from the
results of an examination the examiner
must judge not only of the knowledge
and experience of the applicant, but of
the. latter's resourcefulness and ability to
meet an emergency — qualities that should
be possessed by every engineer.

It is probable that the examiner was
justified in refusing to grant a second-
class license to the engineer mentioned,
although he had run a plant for seven
vears. Experience is a good teacher, but

August 29, 1911

P O W E R

335

even that cannot make a capable engineer
out of some men. If this man had been
certain as to his ability, why did he not
bring his case before the Board of Ap-
peal.*? Of course, occasionally some
engineer feels that he should have been
granted the license which w-.s refused,
but generally he studies and works the
harder and tries again.

I once heard an examiner ask an appli-
cant for a second-class license how he
would proceed to lower the pressure at
which a pop safety valve would blow, and
the reply was as follows: "I would screw
down on the spring." Another was asked
to explain the working of an injector
and replied, "It works by suction," which
was all the answer he could give. A
second-class license gives the holder the
right to operate first-class plants and in
many places they are practically in
o'large for days at a time.

The idea that men are required to take
several examinations before the license
is granted that the examiner may obtain
a fee for each examination does not seem
plausible, when it is remembered that
they are paid fixed salaries and that all
fees so obtained go to the State. A small
fee is no doubt necessary to prevent
waste of time by those who might come
needlessly were no fee charged. When
compared with the S5 to SIO per year
charged in some places, the charge of one
dollar per examination seems reasonable.

Mr. Levy's suggestion that the first-
class engineers and the State examiners
were in league to keep down the other
engineers would be amusing were it not
for the slur it seeks to cast upon a large
number of conscientious and responsible
men. However, as there is little danger
of its being taken seriously by anyone,
further comment seems unnecessary.

That it is easier to look for flaws in
the present law than to devise a better
one, is shown by the fact that other States
are using the Massachusetts law as a
model.

If the standard of examinations be
lowered it will lower the value of every
engineer's license, whether in force at the
time or given later.

Roy W. Lyman.

Ware, Mass.

If such a condition exists as is pictured
by Mr. Levy in the August 1 issue, it is
high time that the authorities were com-
^"lled to look into the matter as it is

■ispiracy pure and simple.

I have often questioned why an en-
. gineer should be obliged to pay a tax
pn his method of earning a livelihood.
Is he a nuisance? Is his business ob-
lecfionable or detrimental to the general
public? Why should he pay this tax
liny more than the blacksmith or the
tinker? The wages compare favorably
' ith those of these callings.

I firmly believe that a man in charge
■if or responsible for a steam boiler

should be examined as to his fitness for
the position. I do not believe, how-
ever, that he should be examined on sub-
jects entirely foreign to the boiler. If
he is competent to handle the steam-
making end of the plant, his duty to
the public is accomplished. If he can-
not make good in the engine room, it is
up to his employer. And last but not
least, let the examination fee come out
of the public treasury and not out of
the wages of a man who has to struggle
to make both ends meet. I have held a
A^assachusetts license for years, but I
could not pass the present examination
if required to do so.

Sherborn Foster.
Bennington, N. H.

Referring to J. A. Levy's protest
against the tendency of the present-day
license examinations running to tech-
nicalities and the grading of engineers,
I think that while the questions should
as far as possible avoid theory, still
they ought to be very thorough as far as
the applicant's knowledge of boilers, the
expansive power of steam and his
knowledge of combustion, furnaces
and their handling is concerned. For
instance, he should know the safe
working percentage of the various kinds
of joints, the bursting and working pres-
sure, capacity of boilers, staying of flat
surfaces and the proper tensile strength
of plates and shearing strength of
rivets; in fact, he should be able to de-
cide for himself whether the boiler is
safe for the pressure carried, and if
not, he should have the backbone to
refuse to operate it and be backed up
by the examining engineers. The dan-
gers of scale and inside and outside
corrosion, their cause and prevention,
the proper placing of the accessories to
the boilers, feed pumps, injectors, etc.,
should also be covered as the boiler
plant is really the place where the
greatest danger lies and should be more
thoroughly gone into than any other part
of the plant.

The ordinary operation of engines and
dynamos could then be taken up in
order to ascertain if the applicant is
familiar with the dangers incident to
handling them, but as those dangers are
more or less local I do not think it nec-
essao' to go into the design of the vari-
ous machines on the market today. I
have always looked on my license as a
guarantee to the man employing me
that I was capable of directing and ad-
vising repairs or changes to be made in
the present plant or the installation of
new units. I have met a good many
engineers who as soon as Ihcy got a
license dropped all further study. This
is altogether wrong. An engineer to be
worthy of the name must read continual-
ly; besides going over the old sub-
jects he must buy books and seek to
find out the cause of all the effects he

sees himself and hears about; otherwise
we are not worth a laborer's wages if
we only know how high to carry water
and when to blow the whistle.

Knowledge together with organization
will advance us to the position we ought
to occupy in the industrial world. There-
fore I say, let the examination test a
man's knowledge in all essentials to
safety which cannot be done without in
a measure testing his efficiency. As to
the grading of engineers, I agree with
Mr. Levy that one grade is sufficient;
then let the man advance himself. I
think Chicago has about as good a
license law as any city. The board
is composed of practical men, and
while in the past there may have
been some slight irregularities, still the
results have been excellent. My ex-
amination, as I remember it, was en-
tirely unobjectionable and yet sufficiently
comprehensive. 1 know I put in eight
or nine hours of hard writing and I have
heard some say they took two days to
complete it. Judging from the personnel
of the present board, I think the past
will be improved upon by their work.
Here we have only one grade, and a
man must do two years' firing before
he can come up for examination.

If we want to increase the respect for
our calling we must have the courage
of our convictions, even to falling under
the displeasure of out- employer if nec-
essary when ordered to do things we
know are bad engineering.

It is no excuse to say, "the boss owns
the plant." We are in charge and re-
sponsible for it.

William Chaddick.

Chicago. III.

Sizes of Belts

In the August 8 issue Mr. Mosher gives
a formula for determining the size of belt
for transmitting a certain load. In this
formula he recommends approximately
60 pounds as L the working load per
inch of width of a single belt. The usu-
ally accepted effective pull is about 33
pounds per inch of width, making a belt
I inch in width, traveling at 1000 feet
per minute, capable of transmitting I
horsepower, although many people have
increased this pull to a point at which 1
horsepower will be transmitted by a I-
inch belt running at (lOO feet per minute.
The high limit of ."i? pounds per inch of
width may be well within the capacity
for the belt as a transmitting medium so
far as its strength for direct tension is
concerned, but any such pull as this will
result in considerable stretching. Be-
sides increased attention, this will result
in the use of much narrower pulleys;
also, although the first cost is less, the
maintenance expense is greater.

F. W, Taylor, in his study of this situa-
tion, recommends an cfTcclivc pull of 25
pounds per inch of width for a double

336

POWER

August 29, 19 n

belt, and while this seems very low, it
doubtless results in an exceedingly low
n^aintenance cost, and the total resultant
cost is correspondingly low.

The ditficulty in many factories is that
the belt pulls are far too great for satis-
factory operating conditions, mostly
caused by not being able to get a suffi-
cient frictional contact between the belt
and the pulley surfaces, which results
in very tight belts, and consequently hard
running shafting and used up belting.
Henry D. Jackson.

Boston, Mass.

Going over the Cliief ,s Head

The editorial in the July 25 issue under
the above caption is good as far as it
goes, but it fails to say a word that will
help the man who needs it the most, the
manager who will encourage that sort of
business.

This kind of manager seemingly does
not realize that he is reducing the effi-
ciency of his entire engine-room force
at least 50 per cent., for every man in it
is only keeping one eye on his work,
the other being on the man who is sus-
pected of running to the boss. Neither
can this manager understand that a man
who will "knock" his chief will, if op-
portunity offers, just as quickly knock
the manager himself, or perhaps delib-
erately injure the company if he thinks
it will further his own schemes.

In a town where I once worked there
was a large ice plant employing two en-
gineers; one was, by courtesy, called the
chief. The title was an extremely hollow
one, however, for he did not hire his
help, nor have any great amount of au-
thority over them. He merely had the
day shift, did all the repairing and took
the kicking, when there was any, all for
an e.Ntra $10 a month.

The second engineer had been in that
one position for five years, and during
that time had worked with six different
chiefs, every one of whom quit his job
after having some trouble with this as-
sistant. The manager made it a practice
of coming to the plant in the evening,
and the assistant usually conducted him
around, pointing out the ways he would
run the plant.

I was offered the chief's position, and
agreed to take it, provided I was given
entire charge of the engine room and of
everyone in it, and if the manager agreed
to keep out except when I was there.
He refused, however, saying that it would
be suicidal to allow any engineer to gain
such control of the plant; that at any
time he got a "grouch" he would quit
and take his whole force with him.

Soon after this the assistant was de-
tected in the act of putting soda into the
reboiler to make white ice, and incident-
ally cause trouble for the chief. When
this was brought to the attention of the
manager he refused to credit it; he could

not believe such a faithful man could be
guilty of such an act, and he allowed the
chief to quit. But later the manager saw
his folly, when this assistant engineer
told the largest stockholder in the com-
pany that the manager was putting in
too much of his time during business
hours in a nearby cigar stand playing
"solo."

A short time ago I was visited by the
manager of a plant in a distant part of
the State, who made what appeared to
be a very attractive offer, a larger and
finer plant, a nice locality and a sub-
stantial raise in wages. My first inclina-
tion was to jump at it, but when I con-
sidered how few bosses there are like
mine, and how many of the other kind,
I refused the offer.

I am in charge of a small but growing
plant, hire all my help, buy my supplies,
and run or lay off as I think best. The
manager would no more ask my assistant
anything about the work than he would
think of turning his checkbook over to
him. All he seems to care for is that I
furnish him with good ice whenever he
needs it, and at a reasonable cost. He
apparently does not fear that I will get
angry and cripple the plant by leaving
with my help during the summer rush.
Albert J. Wickes.

San Luis Obispo, Cal.

Value of CO2 Recorder

No doubt exists in the minds of engi-
neers but that boiler-plant efficiencies
obtained in tests and special runs are
rarely, if at all, attained in actual opera-
tion. Evaporations of 10 or 11 pounds
from and at 212 degrees per pound of
coal are often obtained in tests. When
it comes to averaging up the monthly
coal bill, however, and the monthly evap-
oration, it is found that the efficiency is
considerably lower.

The boiler plant does not operate con-
tinuously; banked fires are carried, fur-
naces are cleaned and other operating
conditions cause this discrepancy in the
efficiency of steam formation. An addi-
tional reason, probably of as great
weight, is that under actual operating
conditions the boiler-room force is not
keyed up to its best, work and is not con-
scientiously and persistently working for
a record.

What are the conditions attendant to
boiler acceptance tests and special runs
for making records which cause these
high efficiencies of operation? The load
is usually favorable, the coal is that best
suited to the grate or stoker, and an ex-
pert whose experience and training have
been i.long the lines of obtaining rec-
ord boiler-plant performances, are all
brought together. What proportion of
the high efficiency obtained is to be ac-
credited to the expert fireman and what
proportion to other favorable conditions
is. of course, an open question. The

expert operator watches his fires with
the very keenest attention; the small-
est indication of a burnt-out hole gets
his immediate care; he seems to know
intuitively just what draft is needed at
every moment, when and how much, and
where to place his coal.

The result is that the loss of coal
through the grates is a minimum. Sim-
ilarly the loss due to the escape of com-
bustible gases and the loss in smoke
are held down to practically nothing.
The loss of heat by radiation he
cannot well regulate. Finally, the great-
est source of loss in the boiler plant —
the heat in the chimney gases — is held
down to the very lowest figure.

That this loss up the chimney is low
is proved conclusively by turning over
the pages of Power and other technical
papers, and referring to the published
tests of boilers, where it will invariably
be found that with high overall boiler
efficiencies, the percentage of CO= is
high, indicating a small volume of waste
gases carrying off heat. For instance,
reference to the tests on page 721 of
Power (May 9, 1911), shows efficiencies
as high as 83.3 per cent, with CO: as
high as 14.3 per cent. In Power for
January 31. 1911, H. R. Mason gives
tests where the percentage of CO^ was
11.35 and the efficiency of boiler alone
74.2. A test of the electric plant at
Vitry-sur-Seine (Zeitschrift des Bayer-
ischen Revisions-Vereins, January 31,
1911), shows with CO: 12.4 per cent.,
an efficiency of boiler and superheater
of 77.92 per cent. Reference need only
be made to other tests and acceptance
trials for further evidence of the attend-
ance of high per cent. CO: with high
efficiencies. A study of 293 of the tests
made by the United States Geological
Survey at St. Louis shows (page 27,
Bulletin No. 325, United States Geo-
logical Survey) that with an increase of
CO; from 6 to 12 per cent, the efficiency
increased from 54 to 66 per cent. In
these tests the amount of air infiltration
amounted to "50 per cent, of the volume
present in the rear of the combustion
chamber."

This letter has been prompted by the
reading of Mr. Vassar's letter in your
issue of July 11, and also his former
correspondence, together with E. A.
Uehling's criticisms.

Mr. Vassar points out that one of the
great drawbacks to the use of CO: per-
centages as a guide to economical boiler-
plant operation is that it is difficult to
take CO: samples from the flue which
are true averages and thus to obtain CO3
percentages which are actually repre-
sentative of plant conditions. Where a
sample bottle is filled in a short time,
it is entirely possible that the sample
does not represent a true average of the
flue gases. It may be added that, where
a sample is taken over a long period,
sav. eight hours, the analvsis is of no

August 29, 1911

POWER

337

value in studying the influence of load
conditions, frequency of firing, thickness
of fire, opening of fire doors, draft, etc.,
on the heat carried away in the waste
gases. On the other hand, with a
pneumatic CO.' machine, drawing the
flue gas continually from the flue in a
considerable amount over that actually
required for analysis and recording and
indicating continuously the per cent. CO:,,
the effect of small variations in the
constituents of the sample of the gas
being drawn at any instant of time are
averaged up. The process might be com-
pared to a method of coal analysis in
which little pieces of coal were being
continually taken from a coal chute
through which all the coal passed. The
average of the continuous analysis
would be as true an analysis of the
whole coal pile as that obtained with the
method of selecting an average sample,
irrespective of the fact that continuous
sampling was done at the same point of
the chute.

Both previous writers have agreed that
many other things tnust be taken into
account in the boiler plant before we
can arrive at a conclusion as to the re-
lation of combustion efficiency and per
cent. C0=. Other things being constant,
it is, of course, certain that the smaller
the waste in any given direction the
greater will be the efficiency. But where
the other factors vary, it is absurd to
attempt to set down hard and fast rules
concerning what percentage of CO;
should be carried in a boiler plant. We
might just as well say that a certain
vacuum should be carried in all steam-
condensing plants, regardless of the type
of prime mover, what the cost of pump-
ing the water is, or what the cost of the
steam is, or how much it costs to run
the auxiliaries or any other of the in-
numerable first costs and operating-cost
figures, which should rightfully enter in-
to the determination of the most eco-
nomical vacuum. Still, we do not find
engineers dispensing with the vacuum
gage, because perhaps it is not econom-
ical to carry more than 27 inches vacuum
in a given plant (since when above that
vacuum the cost of attainment overbal-
ances the economy obtained). On the
contrary, we find the engineer continual-
ly striving to hold up his vacuum, and
while at times he may overreach, the
yearly average, which is the important
item, remains at the high figure neces-
sary for economy.

The principles of scientific manage-
ment have shown that definite aims and
ideals are absolutely essential to high
efficiencies. It is found then that in
scientific management there is always a
goal for whose attainment strenuous ef-
fort is put forth. In the steam plant,
and especially the boiler plant, these
goals have been somewhat obscure.
While the chief engineer is striving to
show a low monthly or yearly cost per

kilowatt-hour, the fireman strives to
"make good" by shoveling coal as in-
dustriously as he can.

Scientific management teaches that the
ultimate goal cannot be won without
there being set down minor goals, which
are to be aimed at day by day and re-
sult in the attainment of highest total
efficiency.

Therefore, the engine is found
equipped with an indicator, the switch-
board with its electrical instruments, the
condenser with the vacuum gage, the
hotwell with its thermometer, the feed-
water heater with its thermometer, the
boiler with the draft gage, steam gage,
feed-water meter, steam meter and the
waste meter, a meter giving the per-
centage of carbon dioxide and the tem-
perature of the flue gases. The engi-
neer and fireman are supplied with small
definite aims toward which they strive
and in so doing the great goal of high
plant efficiency over the whole year is
obtained.

Paul A. Bancel.

New York City.

Central Station versus Isolated
Plant

In the issue of July 11, Emmet Bald-
win tells us that the plant he ran was
turned over to the central station. It
seems to me that if the details of this
plant were made known, as well as the
deal itself, it might be interesting.

In the first place, what price did the
central station quote? If the plant is
five miles from a railroad the chances
of other plants in the vicinity are very
slim. If the central station has to put
up a long transmission line and then
only furnish 93 horsepower, we would
expect the price to be anything but low.

How much heat is required in the
winter time?-' If the buildings are large,
as the length of the steam line would
indicate, this alone would be quite an
item.

Is the plant motor driven now or will
considerable money have to be expended
for the new installation?

Is the high cost all due to the trans-
portation of coal, or to other things
which might be improved? Is the heat-
ing done with exhaust steam or is this
used to heat up the atmosphere and live
steam used for the interior?

Is steam used for other purposes about
the plant?

Is there a feed-water heater in use?
Why not send in a couple of the indi-
cator cards for publication?

Why is it necessary to have 148 feet
and seven elbows in the steam line from
the boilers to the engines, and is it
covered ?

What is the size of the pipe that causes
25 pounds drop in pressure?

Are the gages oorrcci? Many more
questions could be asked.

I hope Mr. Baldwin will take this in
the spirit in which it was written. As
far as the writer knows, Mr. Baldwin
may have the plant in first-class condi-
tion and it may be a legitimate case for
the central station.

Probably 95 per cent, of the readers
of Power are interested in the survival
of the isolated plant. The central-sta-
tion people are not backward in advocat-
ing their cause. Let us have the details
of some of these cases and let the read-
ers line up on the side of the isolated
plant and see what they can make of
them.

John Bailey.

Milwaukee, Wis.

I can sympathize with the engineer
in the big city who has the central sta-
tion after his plant and has to fight to
keep his job, for I have a central-sta-
tion man after the plant that I am run-
ning. I helped this man to all of the
ins and outs of the plant, and now he is
trying to get a contract to run it. But,
I am working hard enough to make a
good showing and to convince the cen-
tral-station man that there is no money
in it for him. He will not bother me any
more for a while.

Now, why should the engineers in any
State or town take Power to task for
advertising anything in the advertising
columns? That very advertisement
against which they complain results in
giving me the benefit of many men's best
ideas for which I pay Po'ser about 4'/,
cents a copy. I study carefully all there
is in each issue and I am not slow to
take advantage of all the good things
that suggest themselves to me and make
use of them.

If an engineer has a plant that has an
inefficient equipment, if is up to him to
see that the management understands
the case when central-station figures are
being considered.

Not long since I called on an engineer
running a small refrigerating plant. The
plant was going and so was the engineer.
The thermometer was going up all the
time. The engineer was complaining that
he could not get the brine tank cold
enough to freeze any water. I stood
around awhile taking in the condition of
things. The thermometer was going up
and the man in charge kept saying, "I
don't know what is the matter." I knew,
however, if the brine had been attended
to as faithfully as his own tank, the
thermometer would have been down to
zero instead of 15 degrees above freez-
ing, and the cost of ite would have
been one cent a pound instead of 100
cents.

If these mulelike engineers would let
a little sunshine into their foggy brains
there would be no reason to kick against
the central-station activity.

H. B. Willis.

Providence, R. I.

338

P O ^X■ E R

August 29, 1911

Alternating-current Power
With only voltmeters and ammeters,
how can I find out the true power at the
switchboard of an alternating-current sta-
tion ?

C. M.
You cannot ascertain the true power
without using a wattmeter or else using
a voltmeter, ammeter and power- factor
meter together. In using the three in-
struments, all three readings must be
taken at practically the same moment.

Power 171 a Three Phase Circuit

Kow is the power in a three-phase al-
ternating-current circuit determined if
no wattmeter is available?

M. H. M.

Take simultaneous readings of the volt-
meter, ammeter (in one leg) and power-
factor meter. Multiply the three together
and multiply the result by 1.732; the final
result will be the power in watts if the
circuit is balanced — that is, if the total
load is divided equally between the three
legs.

Brine Mixtures

What is the right proportion of calcium
chloride to water for a brine in a meat
box? What should the brine test with a
salometer? Does the salometer show
the specific gravity? Does it do harm if
ice collects on the pipes in the brine?
H. J. M.

To make a good brine for refrigerating
purposes add about 24 per cent., by
weight, of calcium chloride to the water.
The specific gravity of this solution is
1.2, which is equivalent to 25 degrees
Baume, or 100 degrees on a salometer.
This brine freezes at a temperature of
15 degrees Fahrenheit. It can be safely
used for back pressures not lower than
7 pounds gage.

Ice should not be allowed to collect
on the coils, as it acts as an insulation,
preventing the transfer of heat from the
brine to the ammonia.

Pressure in Stanaptpe

A vertical pipe 150 feet high contains
enough water to create a pressure of 50
pounds pe. square inch at the bottom.
Both ends of the pipe are closed and
pressure gages are placed at the top
and bottom of the pipe, air or steam be-
ing forced into the upper end of the
pipe until the upper gage shows a pres-
sure of 100 pounds per square inch.
What pressure will the lower gage show?
For a pipe arranged the same as before

Questions aro

not answered unless

accompanied by the^

name and address of the

inquirer. This page is

for you when stuck-

use it

with the exception that compressed air
at 51 pounds pressure per square inch is
admitted at the lower end of the pipe,
what pressure will be shown by the gage
at its highest point?

B. W.

The gage at the bottom of the pipe
will register the pressure due to the hight
of the water, plus the pressure of the
air above the water, or
50 + 100 = 150 pounds per square inch.

In the second arrangement, the air
will enter the pipe until there is a pres-
sure of 51 pounds at the bottom of the
pipe, and I pound at the top. Then the
water pressure will balance the air pres-
sure and no more air will enter the pipe.

Percentage of CJcarance
How can I calculate the percentage of
clearance in an engine cylinder 42x72
inches? The piston is J-r inch from the
head at the end of the stroke.

A. L. J.
Clearance is the volume between the
piston and the face of the cutoff valve
when the engine is on the center. To
measure it, place the engine on the cen-
ter, close the exhaust valve and fill the
space with water up to the level of the
steam or cutoff valve, being careful to
avoid air pockets. The percentage of
clearance is the clearance volume thus
determined divided by the piston dis-
placement and multiplied by 100. If, for
instance, your 42-inch engine had a
stroke of 6 feet, or 72 inches, the dis-
placement would be

1385.4 X 72 inches
(1385.4 is the area of a 42-inch circle).
If it took 3000 cubic inches to fill the
clearance space the percentage of clear-
ance would be

,^ooo X lOO

.; = \ bi) cent.

1385,4 X 7-'
This must not be confounded with the
mechanical or "striking" clearance, which
is not expressed in percentage of the
stroke but by its actual measurement.
The striking clearance of the engine
would be said to be ',s inch.

Pitch Diameter of Gears

If a gear has 22 teeth and is 6 pitch,
how far will a rack be moved in 2^2
revolutions of the gear?

H. C. B.
The pitch is the number of teeth
divided by the pitch diameter. Hence the
number of teeth divided by the pitch
will give the diameter

22 -f- 6 = 3J^ inches
The circumference is

3.1416 X ^7i = 11-52
In 2.5 revolutions it would therefore
move the rack

11.52 V 2.5 = 28.8 inches.

Position of Shunt Fiehi

Is there any difference, electrically
speaking, in having the shunt field of a
compound-wound, direct-current gener-
ator nearest the armature on the pole?
S. S. H.

Yes, a slight difference. The series
winding is usually put next to the end
of the pole because the leakage of mag-
netism produced by it is less there and
its effect on the armature is greater than
if it were put next to the yoke. With the
series winding next to the pole, the
shunt winding, of course, must go next
to the yoke if they are side by side.

Cause of High Discharge
Pressure

The pressure of the discharge from
our ammonia compressor has increased
greatly. What is the cause?

S. H. S.

A high discharge pressure in an am-
monia-compression system may be due
to too little cooling water showered over
the condenser; too high a temperature
of the cooling water; too small an ef-
fective cooling surface for the refrigerat-
ing effect required and to air and other
fixed gases in the system.

The best way to remove these gases
where open-air condensers are used is
to shut off each condenser section from
the system separately. Allow the cool-
ing water to flow over the section shut
off for from 5 to 10 minutes so as to
be sure that practically all the ammonia
is liquefied. Then shut off the water
supply to this section and open the
purge valve at the end of the top pipe
slightly. As soon as frost appears on
the outlet end of this valve, cr when
fumes issue, it should be shut immedi-
ately. Each condenser section should be
purged in the same way.

August 29, 1911

POWER

339

I>Mied Weekly by the

Hill Publishing Company

JOBX A. Hill, Prey, an J Treay. Robt McKKAS,Sec"y.

505 Pearl Street. New York.

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Subscribers in Great Britain, Europe
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Entered as second class matter. De-
cember 20. 1910. at the post office at
.\ew York, .New York, under the Act
of .March 3, 1879.

Cable address, " PowTrB," N. Y.
Business Telegraph Code.

CIRCULATION STATEilEXT

Of this ismie 34,000 cojiirn arc printed.
Xone tent free regularly, no returns from
rirg companies, no baek numbers. Figures
. (ire, net rinulation

Contents

The Cincinnati Water Works

Kinks at Pendleton (;enerating Station.

Plum Street iJenerating Station

An Ideal Central Station

Saving with Imv,- Pressure Turbine....

The Zoelly Steam Turbine

Central Engine Koom Oiling System...

Operating Alternately on the Two Wire
and Three Wire Plans

Undercutting Commutator Mica and Re-
moving Bad Spots

Isolatecl Plant Operating Costs

Mr. Cranes Switchboard

Ganlfying Crude Oil

A Steam Engineer's Experience with
<;as Power

A Klaaslroiis Dose of Water

Points In the Operation of Suction Pro-
ducer Plants

Why the <ia» Supply Failed

arlKmlzIng Internal-Combustion En-
gines

.'htenlng Pistons Improves F'lexlblllty
and Acceleration

Iriirtlral l,etters:

Approximflte Meat Value of Coal
....<»ll Filtering System .... lint
Beflrlngs ..Automatic Control of
Circulating Water . . Iillnpldaled
Boiler Conditions. . . .necpilred
Nene. . . .Ftecelver Condensation
....Scale In Suction Pipe..., Fir-
ing Boilers 3.'J1-

liUciisslon I^-lters:

Mflssflchtisetfs Elrense T^ws and
Examiners .. .Sizes of Belts .. .
f;olng over the Chiefs Heart ....
Value of CO, Recorder. .. .Central
Station versus Isolated Plant. . . ..1.14-

F.rtllorlals 33ft.

Measurement of Air Velorllles

Ilentlne and Ventilating High School
Bullrtlnes

Flywheel Explosion at West Berlin....

318
322

Water in Power Plant Piping

Water in the steam pipes of a power
plant is to be avoided as much as pos-
sible. Its presence to some extent is, of
course, inevitable — even in pipes carry-
ing stiperheated steam there may be
some water along the bottom of the pipe
— but the quantity may be reduced to
the minimum by the use of nonconducting
coverings which retard the transfer of heat
from the steam to the air. At a velocity
of one hundred feet per second, which is
not an unusual speed for steam in the
pipes in the modern power plant, the
water, if not taken care of, is liable to
be caught up in slugs and carried along
with the steam to be arrested at the first
short turn or at the end of the pipe.

Just as a sixty-mile gale raises great
waves on the ocean, so will a current of
steam of high velocity raise waves from
the water in the pipe or carry the water
along by friction to the engine or turbine
where a very small quantity of it may do
a great deal of damage. If a pipe has
a uniform pitch from its highest point
to where it turns to the engine or tur-
bine, there is no danger that enough
water will collect anywhere to form a
slug. But if there are low places or
pockets, they will fill with water while
the steam is quiet, and when the current
starts it will be thrown into billows
which, whether high enough to fill the
pipe or not, will rush along with the
steam and produce water hammer, start
leaks and perhaps wreck a fitting or the

pipe-
To prevent this, drain pipes should be
connected which will under all circurri/-
stances take care of all of the con-
densation as rapidly as it forms. It is
needless to specialize the parts of any
pipe system requiring drains, for wher-
ever steam circulates it condenses;
therefore, these drains should be ample
in size, properly located and kept open
all of the time.

Branches of any considerable diam-
eter leading from all pipes should be
provided with stop valves at the highest
point if possible, so that condensation
cannot accumulate. If it is not practic-
able to so place all of them, those that
may pocket water should be equipped
with drains just above the seat.

In some systems of piping the main
line is arranged tn be cut into sections
if so desired. Such sections when
"dead" should be drained to the at-

mosphere to prevent filling with water
from other sections through leaking or
partially closed valves.

Mr. Zoelly' s Mews on Steam
Turbines

Much interest was aroused by the an-
nouncement that Mr. H. Zoelly, inventor
of the turbine which is built by the
Zoelly syndicate all over Europe, would
present a paper at the Zurich meeting
of the Institution of Mechanical Engi-
neers. The paper, an abstract of which
appears on pages 318-322, hardly realizes
the expectations which were aroused by
the prominence and ability of its author.
It proves to be little more than a descrip-
tion of the Zoelly turbine as built by
Escher, Wyss & Co., which is, of course,
very interesting, but does not satisfy
one's desire for more analytical informa-
tion.

Mr. Zoelly advocates throttle governing
and says that it "works particularly eco-
nomically at partial loads," just when
the baleful effects of the excessive throt-
tling would be expected to be greatest,
backing up his assertion by reference
to tests where the consumption varied
only as follows:

Relative Thermal Ef-

ficiency Referrki)

TO STEA.M

lielative

Per Cent.

I{ating

Water Rate

Unthrottled

Throtlleil

104 7

1.000

1 000

1 000

77 3

1 039

0 964

I) 091

55.0

1 087

0 920

0 99t

28 4

1 208

0 872

1 021

102 6

1 000

1 000

1.000

75 7

1 048

0 9.")3

0 997

.51 3

1 114

0 923

25.5

1 329

0 S34

0 !)97

99 5

1 000

1 000

1 .000

80 4

1 O.W

0 9.-.4

0 991

M 1
-•6 8

1 l!tO

0 S7.S

0 9.->t<

1 4.V)

0 819

0 973

102 9

1 000

1 000

I 000

79 1

1 042

0 937

0 980

■nO 5

1 115

0 881

0 975

The last column is based upon the
efficiencies referred to the steain after
it has been throttled and not including
the loss due to throttling. If the figures
are right, and they will be found to
correspond to those in the paper (see
page 322). the blading of the first turbine
was more efficient .if a quarter and that of
the second at a half than at normal load,
while the third was more efficient at
quarter than at half load. When the effi-
ciencies are referred to the steam as

340

POWER

August 29, 1911

furnished to the turbine and include the
effect of throttling they run down as the
load is decreased, as would be expected.
It would have been interesting if the
author had expanded his statement that
this economical working at partial loads
*'is only possible when simple velocity
wheels are used in connection with paral-
lel guide nozzles throughout the whole
turbine, and provided that the most
favorable choice is made in regard to
the subdivision of stages."

Mr. Zoelly says that the many tests
which he has made "all go to show that
it is not possible to obtain a higher
thermal efficiency with compound-veloc-
ity wheels than fifty-eight per cent.,
whereas with a turbine designed with
simple-velocity stages it is possible to
obtain an efficiency of seventy-three per
cent, and more." Curtis turbines, in
which the compound-velocity stage is
•used throughout, have shown at the
Commonwealth station in Chicago a
thermal efficiency of 69.8 per cent., at
the Waterside station of the New York
Edison Company of 70.5 per cent., and
at the L-street station of the Boston Edi-
son Company 72.2 per cent.

The author declares against the use
of the compound-velocity blading even
for the initial stages except where, as
in marine work, slow rotative speed is
imperative. Yet the highest efficiencies
so far attained have been produced by
combination turbines having compound-
velocity initial stages. These, however,
had Parsons or reaction blading for the
rest, and his comments in this respect
are restricted to impulse turbines.

The argument, not entered into in the
paper, against the compound-velocity
stage is that the first blade takes out
the greater part of the energy, leaving
too little to the second to justify its
use. When a parallel instead of a
divergent nozzle is used, as Mr. Zoelly
advocates, the steam will go on expand-
ing in the blades as its energy is ab-
sorbed, increasing the velocity in the
second to\v and making it do a larger
proportion of the work. A little discus-
sion of this fact, of the modification of
the blading found desirable to meet
these conditions, and similar topics,
would have made the paper appear more
as though it were Ingenieur Zoelly rather
than Director Zoelly who was talking.

Sand fo-r Hot Boxes

Liberal applications of sharp sand to
a hot bearing for the purpose of reduc-
ing its temperature would be considered
by most engineers as both heroic and
dangerous treatment. But there are many
instances in which the use of sand or
any of the softer kinds of grit, such as
rottenstone or grindstone dust, will prove
highly beneficial. Often the natural
shrinkage of the metal in a rebabbitted
box will pinch the shaft to such an ex-

tent that some metal must be removed
before cool running is possible; some-
times a bearing gets "dry" and the sur-
face of the babbitt is "wiped" or swept
part way around the box, thus causing
the shaft to bind. In either of these
cases the surfaces may be brought into
satisfactory running condition by feeding
sand and oil or sand and water to the
bearing until it runs cool.

Sapolio is used by a number of erect-
ing engineers for the purpose of bring-
ing the main bearings of new engines in-
to the proper working condition. With
the cap off, the engine is run at normal
speed with a small stream of water or oil
playing on the shaft, and a cake of Sapolio
held in the hand is slowly moved from
end to end of the bearing until the shaft
shows bright the whole length.

On many ocean steamers a box of
sand is a part of the engineer's emergency
outfit, and it is kept handy for use in
case any of the propeller-shaft bearings
begin to heat.

Power Plant Design

Some plants are so well laid out that
even though they are allowed to get a
little "down at the heel" they still show
fairly good economy. Other plants,
poorly laid out by more or less incom-
petent and inexperienced men, are so
handicapped from the very beginning
that to secure reasonable economy with
them requires surpassing effort.

The particular build of boiler or en-
gine selected does not make any ver\'
great difference so long as the type is
suitable for the purposes of the plant.
But the sizes of the various pieces of
apparatus and their arrangement may
make vast differences in the results the
plant will yield. Take, for example, the
matter of chimney design. A surprising-
ly large number of plants are handi-
capped by undersized chimneys. Usual-
ly the trouble is that the chimney is too
short.

The capacity of a chimney depends
upon its cross-sectional area and its
hight. The capacity increases directly
as the area and directly as the square
root of the hight. The comparative cost
of a chimney increases but slightly with
an increase in diameter or cross-sectional
area, but it increases greatly with an
increase in hight. Hence, the designer
is tempted to select a short chimney of
large diameter rather than a taller chim-
ney of smaller diameter. He loses sight
of the fact that the draft depends upon
the hight and that any chimney, no mat-
ter how ample in diameter, is inadequate
if it cannot furnish enough draft to pull
the air through the fuel bed.

Thus, while the designer may succeed
in saving a few dollars in the first cost
of a plant, he often condemns it to
perpetual inefficiency which in the end
may assume unbelievable proportions.

The Engineer's Place Is in
tile Engine Room

Should the operating engineer be com-
pelled to leave the engine or boiler room
while it is in operation, especially when
he does his own firing? Aside from the
matter of safety, can the manufacturer
afford to allow the machinery in the
steam plant to operate without an at-
tendant at hand?

By compelling the engineer to do out-
side work, a saving of a few dollars may
be made, but one slight accident, which
probably could have been prevented had
the engineer been present, will wipe out
all of the saving made by the outside
work he had done.

An engineer, especially in a small
plant, has several unemployed hours each
day, but his presence is necessary never-
theless. Numerous flywheel explosions
have been prevented because the engi-
neer was at hand and shut the throttle
valve in time. Crank-pin boxes have
been saved because the man on watch
was attending to his duties when the oil
cup failed to feed. Tubes in boilers will
sometimes burst, but if the fireman is
out in the yard handling scrap iron he
has not much chance to cut out the
boiler in such an event, and thus pre-
vent a shutdown of the entire establish-
ment.

An engineer recently took charge of
a steam plant in which the fireman made
his work a continuous performance. This
apparent industrj- satisfied the superin-
tendent perfectly; he did not take into
consideration the fact that every time
the furnace doors were needlessly open
or the fires sliced and leveled there was
an inrush of cold air which cooled the
furnace gases and cost money.

As the result of the changes made by
the new engineer, one boiler was cut
out of use and the fireman had time to
sit down a few minutes between .each
firing.

The superintendent then objected to
the fireman thus wasting the company's
time, and insisted that when he was not
busy in the boiler room he be employed
on some outside work.

This superintendent does not stand
alone in his attitude toward the men in
the steam plant. It is a common mat-
ter to find an engine or boiler room
deserted because the attendant had been
compelled to do other work than his own.

This being a "Jack of all trades" has
prevented the engineer from gaining a
higher place in the estimation of his em-
ployer. It should be the engineer's aim
to convince those over him that his place
is in the engine room and that he can
save more money for his employer by
attending to his own affairs than he can
by going outside and doing the work of
others.

August 29. 1911

POWER

341

■i^Jk. -^ "^lam^^L.

Measurement of Air Velocities

By F. G. Hechler

In heating and ventilating work it is
often necessan' to determine the amount
of air. supplied by a fan, and especially
in acceptance tests is it necessary to de-
termine the quantity exactly. The volume
of air is expressed in cubic feet, and as
it is nearly always conducted from the
fan through a duct either circular or
rectangular in cross-section, the cross-
sectional area of the conduit and the
velocity of the air through it should be
known as well. The product of the area
in square feet by the velocity in feet
per minute gives the cubic feet supplied
per minute.

The velocity may be determined in
several different ways, though the most
common method is by the use of an ane-
mometer, a small-vaned instrument simi-
lar to a windmill wheel. The wheel is
connected with a recording mechanism
by the use of which in connection with a
stop-watch, or even an ordinary watch,
the speed of the air past the vanes may
be determined. Its convenience is the
only thing to recommend an anemometer,
however, as its readings are subject to
large and uncertain errors. The makers
always supply rating tables with these
instniments, which show the actual ve-
locity corresponding to any apparent ve-
locity as determined by the instrument.
These tables do not show any particular
uniformity in the matter of error at
the different velocities, and after the in-
strument has been in use a short time it
Is likely to give quite different results,
due to wear and dirt getting in the deli-
cate hearings. Bu. even with frequent
calibration they will be reliable only if
rated under conditions similar to those
under which they are to be used. To
show the importance of this, tests made
by a prominent engineer on the meas-
urement of the velocity of air in pipes
by an anemometer showed that the per-
centage of error is not constant and that
it varies with the size of the pipe and
the speed of the air. The size of the
pipes varied from 8 to 24 inches in diam-
eter, and the velocities as given by the
anemometer varied from 14' ^ per cent,
fast to 3(1. fi per cent, slow, as compared
with the true velocity determined from
the time of descent of a large gas
holder of known capacity.

It Is well known that the velocity
of air in a pipe line is not the same
at all pnlnt!«, being greatest at the cen-
ter and least at the sides, where friction

against the surfaces retards it. For a
circular pipe the law of variation is usu-
ally taken to be a parabola; the air mov-
ing in concentric layers with the aver-
age velocity at a point two-thirds of the
radius from the center. This variation
in velocity may partly account for the
uncertain results obtained with an ane-
mometer, and it is evident that an instru-

•a.

Fig. 1. Velocity of Air in Pipes

ment properly calibrated may give too
high a reading if held at the center
of a large duct.

A better way to determine the velocity,
and one which gives much more reliable
results, is to use a Pitot tube. To make
clear the principles on which the use of
this instrument is based, its use for de-
tenning the velocitv in a water main will
be considered. Water is a more concrete
substance than air and hence it is easier

to produce motion, the remaining head
shown by the gage being the "pressure
head." If the pipe were perfectly smooth
and there were no friction losses, the sum
of the velocity and pressure heads would
always equal the static head shown when
there is no flow. The friction losses
are variable and not easily measured,
but the Pitot tube gives a ready method
for finding the velocity head, and from
that the velocity, as shown later.

If a tube be inserted in a pipe line,
as at A, Fig. 2, with its inner end paral-
lel to the axis of the pipe and hence
to the direction of flow of the liquid or
gas, and the outer end connected to a U-
tube filled with water or mercury (de-
pending on the pressure to be measured),
the difference in the hight of the two
columns represents the pressure head
expressed in inches of water or inches of
mercury. If a second tube be placed, as
at B, with its end bent at right angles
so that it is perpendicular to and faces
the flow of the stream, its manometer
tube will give both the pressure head
and the velocity head. If then
the difference between the readings of B
and A are taken, the velocity head pro-
ducing flow is obtained. For convenience,
these two separate gages are usually
combined into one. as shown at C. Here
the tube at the left, similar to A. tends
to -show the pressure head; the tube at
the right, similar to B, shows the pres-
sure head and the velocity head; in other
words, connecting the tubes in this man-
ner automatically performs the above

Fig. 2. Pitot Tube to Measure Velocity of Air

to deal with it; but exactly the same laws
apply in regard to the velocity of air
as hold for water.

A pressure gage connected to a pipe
tine will show a higher pressure with no
flow than when the water is in motion,
and the faster the flow the lower the
pressure shown by the gage. When there
is no flow the gage shows the total or
static head; when the valve is opened and
flow occurs a part of this head Is used up
in causing the water to flow. In other
word'', a "velocity head" Is necessary

subtraction and the reading of this gage
represents the velocity head.

After the velocity head is found, the
velocity is calculated by the formula

r = J Tqh,
where

r — Velocity in feet per second;
h - Velocity head in feet;
g — Acceleration due to gravity in
feet per second per second =:
32.2 feet.
If the manometer contains water and

342

POWER

August 29, 1911

the velocity of air is being determined,
then the head must be changed from
inches of water to feet of air by multi-
plying by the ratio of the density of wa-
ter to that of air. To do this the tem-
perature must be known, as the weight
of a cubic foot of air and of water de-
pends on the temperature. To illHstrate,
assume that the manometer reading h, in
Fig. 2, is 1 inch of water and that the
temperature of the water and of the air
is (30 degrees Fahrenheit. From tables
the weight of 1 cubic foot of water at 60
degrees is 62.31 pounds and of 1 cubic
foot of air at the same temperature is

For any other temperatures, or if
mercury is used in the place of water,
the proper weights per cubic foot would
have to be used.

Heating and Ventilating High
School Buildings*

By Samuel R. Le\x'is

This paper outlines the scheme of heat-
ing and ventilating a new schoolhouse
building in Decatur, 111., and the remodel-
ing of the heating and ventilating appa-
ratus in an established high-school build-

FiG. 1. Underground Conduit to New School Building

formerly heated by 10 warm-air fur-
naces. The ground space for the new
building and its surroundings made it
desirable to eliminate a boiler plant, and
as the furnaces in the old building were
worn out at the time of the designing of
the new building, it would have been nec-
essary to install new heating and ventilat-
ing apparatus. As the old building is
of nonfireproof construction, it was prop-
er to remove all fire from within it. The
new building was to be completed in the
spring of 1911, and the old building must
be provided with a new plant in the fall
of 1909. These considerations prompted
the location of the power house adjacent
to the old building, especially as coal-
storage space could be obtained under
it, and it would be possible to provide
enough capacity to handle the old build-
ing through the winter at minimum cost.

It was decided to install the indirect
type of heating, well governed by auto-
matic regulation, as being the most posi-
tive and sanitary as well as economical.

Direct radiation is used in all toilets,
offices, corridors or rooms with plumb-
ing which might be injured by excessive
cold; having direct radiation in class
rooms tends to keep them warm when the
fans are not in operation, provided they
are furnished with steam. At Decatur
the buildings were so arranged as to

Fir. 2. Re.modeled Scheme of Heating and Ventilating in Old Plant

0.07*34 pound, or the hight of a column
of air in feet to represent the same
pressure as I inch of water would be

fi2..'^7 ^ I _ 816.4

0.0764 12 "12

Using the equation

V = i/tIjIi = 1/2 X3

• 68.03 feet

ing, together with the scheme followed
for supplying both buildings with steam
for heat, electric light and power from
a central point.

The new building is about 500 feet
distant from the old building, which was

2 X 68.03 =
66.2 fed per second

•.\l)stract of paper read tiefore the Amer-
ican Society of nesting and Ventilatins En-
gineers. Ciiicago. July 6 to S.

group the indirect radiation in small
chambers near the banks of flues, and
thus by gravity air circulation keep the
rooms reasonably warm without any di-
rect radiation when the fans were not
in operation. This method is remarkably
successful.

The boiler house is fireproof, and con-
tains three high-pressure horizontal

n August 29, 1911

POWER

343

tubular boilers of 450 rated horsepower'
with standard equipment for bituminous
coal. In a room adjoining the boilers
are the feed-water heater, boiler-feed
pumps, all main operating valves, pres-

with large rear local vent openings> and
all urinals are locally vented, being con-
nected by metal ducts with an exhaust
fan, which is driven hy a direct connected
2' .--horsepower motor. New tile flues

Cfostf Vfe/rf/Xo

no vent screens or registers in the new
building, the ventilation outlets being
finished as far as visible like the rooms,
and thus they are swept out every day,
preventing the unsightly accumulation

Fig. 3. Sectional Elevation through Re.modeled Heating and Ve'ntilating Plant

sure regulator, etc., and two horizontal
turbine-generators, with the accompany-
ing switchboards. The distribution lines
for steam, compressed air and electricity
center in this room. The generators are
for 250- volt direct current; one is of
75 kilowatts capacity and the other a 50-
kilowatt machine.

To the old building are run a 7-inch
steam line and a 2 '.-inch wet return.
and to the new building, in a common
trench 650 feet in length and from 4 to
12 feet underground, are carried a 10-
inch steam and a 4-inch wet return, in
tin-lined WyckofT insulation, and a four-
part vitrified-tile electric conduit. The
main to the new building pitches upward
from the boiler house, and as it is below
the receiver, the condensation in it is
raised to the receiver by a tilting trap.
Proper expansion joints and anchorages
are inserted, the former being accessible
in brick manholes.

In the old high school the supply fan
is a special Sirocco wheel driven by a

supplement the old flues and in the attic
are placed cutoff dampers in all vent
tlues for shutting off the ventilation when
the building is not occupied. This is
effected by compressed air from the en-
gine room.

All class rooms have automatic tem-

FiG. 4. Am Passage to Fan, Old
Building

perature regulation, the thermostats
gradually moving the mixing dampers in
the plenum chambers without curtailing
the volume of air, merely changing its
temperature as required. Cumulative de-
vices are installed by means of which
the power of the entire plant finally goes

of dust, chalk and paper common when
screens are used.

The old high-school building has an
air delivery- of 43,000 cubic feet of air
per minute, and about 3600 square feet
of indirect radiation. The air blown into
the corridors finds its way out through
the toilet rooms by the locally vented
fixtures, and thus there is always a
greater air pressure in the former than
in the latter, thus effectually preventing
odors from the toilets being noticed any-
where in the building. The toilet ven-
tilation is entirely separate from the
room ventilation.

The new high school was naturaJly an
easier and more symmetrical problem,
but the description of the apparatus in
the old building will very nearly suffice
for the new one. The fresh air is drawn
from the second-floor level, and is tem-
pered and delivered by the fans into a
tunnel which extends under the center
of the corridor around three sides of the
building. This tunnel has nine groups
of reheating coils and all of the piping

-f^^ahA^Sfnft Fr^shAr5/^3ft

'».!>mjnjnt»:>t»Ni.'i»»rr^

i. :l..JL.^.„,..Ji,.J a i: S =

L,,_._.,j!",:jj:;]l...,X,,,jLj. jj

' a -o" a»Tp«-

Fic. 5. Heating and Ventilating Scheme in Basement of New Bluldinc Fig. 6. Details of New Building Plant

belled 15-horsepower motor, delivering
tempered air to horizontally placed re-
heating coils in plenum chambers di-
rectly at the bases of the flues. Fresh
air is drawn from the second-story level.
All the toilet rooms have special closets,

to the slowest room to reach 70 degrees
when warming the building in the morn-
ing. On all side-wall air-supply open-
ings are placed adjustable diffusers, by
which the air currents may be deflected
to any part of each room. There arc

for steam and condensation. The tunnel
is of ample size for easy inspection, can
be flushed out with a h»»sc. and is well
lighted with electricity. There is very
little use of metal-duct work. By clos-
ing the doors to the various Cher coils

344

POWER

August 29, 1911

the auditorium or gymnasium may be
ventilated or heated by either fan with-
out affecting the balance of the building.
The supply fans are Sirocco wheels in
double discharge housings propelled by
20-horsepower belted motors. The build-
ing receives 120,000 cubic feet of air per
minute, and there are about 9000 square
feet of indirect radiation.

Exhaust fans for toilet and chemical-
table ventilation are placed in the attic
which, together have a capacity of 15,-
000 cubic feet of air per minute and
have 8 horsepower in motors. The chem-
ical-laboratory ventilation is carried in
vitrified-tile pipes and the fan which

handles the fumes is of special corrosion-
resisting construction. A large, tight
foul-air chamber is formed in the roof
space from which the foul air escapes
through ventilators equipped with com-
pressed-air controlled dampers as de-
scribed for the old building. In both the
old and the new buildings the foul-air
chambers in the attic may be thrown in
connection with the fresh-air intake flues,
thus forming a closed circuit through
which the air may be recirculated over
and over positively; a substantial fuel
saving is thus effected when warming
the building prior to occupancy.

Each room has in its supply flue a

volume damper operated from the back
of the diffuser in the room but located
in the inlet to the flue in the basement.
This arrangement is of great convenience
when adjusting or testing the air dis-
tribution, besides eliminating any unau-
thorized manipulation of the dampers,
as is common with the ordinary type.

The locker and shower rooms in the
subbasement of the new building and all
corridors have both direct radiation and
air supply from the indirect system.
Whenever possible the air is delivered
through or against the direct radiation,
thus increasing its efficiency about three
times and preventing local circulation.

Flywheel Explosion at West Berlin

Tne accompanying illustrations show
to some extent the damage done on
July 4 to the power plant of the Wor-
cester Consolidated Street Railway Com-
pany, at West Berlin, Mass., an account
of which was published in the July 25
issue of Power. The cause of the ac-
cident was stated by J. W. Parker, the
author of the article, as doubtless being
due to the governor safety device failing
to work. The facts do not bear out his
conclusions.

The plant consisted of two 20x42-inch
simple Corliss engines; No. 1 was a
right-hand and No. 2 was a left-hand en-
gine. No. 1 engine, the wrecked unit,
was belted to a 225-kilowatt, direct-cur-
rent generator. It was quite an old ma-
chine and the commutator was nearly
worn out. No. 2 engine was belted to

By W. E. Chandler

All account of the flywheel
explosion which occurred at
West Berlin, Mass. This
article, from the pen of the
chief engineer of the plant,
giics additional informa-
tion as to the probable cause
of the accident.

Both engines were connected to the
same jet condenser which was placed
in the basement between the two en-

Fic. 1. Wrfcked Generator and Parts of the Engine

a direct-current generator of the same
capacity, but it had a new armature and
commutator. One unit made 86 and the
other 89 revolutions per minute.

gines, directly below the gageboard shown
in Fig. 1.

On July 2 and 3, I had sandpapered
the commutators and trimmed the brushes

of both generators and thoroughly in-
spected, adjusted and tested both en-
gines, as 1 expected a heavy day on
the fourth, and every precaution was
taken to guard against failures at the
station.

Inspector Ramsay, of the boiler-in-
spection and engineers-examining de-
partment of the district police, investi-
gated the wreck shortly after the ac-
cident occurred and expressed himself
as being satisfied that it was not caused
by either neglect or carelessness on the
part of anyone.

Both governors were in perfect work-
ing condition and so were the governor
belts. No stop pin was used on the en-
gine, as an idler and its connections run-
ning on -top of the governor belts kept
the weight up at slow speed. If the belt
broke, or got too slack at any time, the
steam-valve gear would not hook on.
These engines were each designed to
carry a load of 409 amperes, and I have
often stood beside the governors and
watched them when carrying 550 am-
peres. A circuit-breaker would go out,
but the engine would be at normal speed
in three strokes; therefore, the faulty-
governor idea can be dismissed.

No flaw was found in any part of the
flywheel and a prominent engine builder
after looking over the broken pieces
stated that it w-as of remarkably good
material. The engines had been run for
12 years, and were still in good condi-
tion; so that any charge of poor ma-
terial and workmanship cannot be proved.

The valves and cylinder were found
to be well lubricated and no signs of
water were evident; thus sudden stop-
page cannot be entertained as the cause.

My theory is that as the commutator
on No. 1 machine was very light, it
would blacken up after a 10- or 12-hour
run and cause the voltage to drop. No.
1 machine had been on the line 14
hours and No. 2 was on 16 hours; the
three hours just previous to the accident
were the heaviest of the day. .\t 9:30
the entire load went off suddenly and

August 29, 1911

POWER

345

No. 2 machine, being at a slightly higher
voltage, would cause current to flow
through the series windings of No. I
machine in the reverse direction; this
would weaken the field and finally motor
the machine. The circuit-breaker had
been expanded from the heat of the few
days past and would not open. As a
result the engine at once reached a high
rate of speed and the outboard bearing
tore loose from its bedplate and was
thrown over No. 2 generator and through
the wall, making the hole shown in the
upper right-hand corner of Fig. 1. This
allowed the crank shaft to swing and
break out the outer side of the main
bearing as shown in Fig. 2.

The rim of the wheel struck the
foundation of the frame and main bear-
ing, breaking it and throwing one piece
weighing about 3800 pounds off the wheel
through the roof, and landing 460 feet
distant. Another piece weighing 1800
pounds went through an 18-inch wall
between the engine and the boiler rooms,
just above the steam main, and landed
between Nos. 1 and 2 boilers. No dam-

in Fig. 1. It knocked No. 1 generator
off its base and turned it partly around,
as shown in Fig. 1. Two spokes went
directly past the generator and through
a 12-inch wall, burying themselves in
the ground 75 feet away. Another piece
struck the brush-holder frame of No. 2
generator and ruined it, also slightly
denting the commutator to the extent
that it was necessary to turn it down.

The flywheel was 16 feet in diameter,
and the rim face was 30 inches wide and
3' J inches thick. It was made in two
sections, three spokes to each half. The
hub was 36 inches square and 30 inches
wide and was held together by four 4-
inch bolts. Each rim flange was bolted
together with four 3-inch bolts. The
spokes were 13' ^ inches wide at the
hub and 10 '4 inches wide at the rim.

The eccentric rod pulled out of the
strap, breaking the wristplate hub and
valve gear. The governor shaft was
sprung, but not broken.

The writer was chief engineer of the
station at the time the wreck occurred,
and hunted for the cause of the accident

FiG. 2. What Was Left of the Engine

age was done to either except to slightly
bend a 1-inch valve stem on the vent
pipe, and break the fulcrum of the lift-
ing lever of a safety valve. Three more
pieces of the rim went through the same
wall into the cellar, cutting off a 7-inch
condenser suction, an 8-inch condenser
discharge and a 14-inch main exhaust
pipe. A 2-inch auxiliary steam line and
an auxiliar>' exhaust line were also
severed. One piece struck the blowoff
pipe of No. 1 boiler and bent it 4 inches
out of line.

The crank shaft, flywheel hub and one
spoke, the crank, connection rod. cross-
head and piston rod. which was pulled
out of the piston (which was not even
cracked), landed in the position shown

for four weeks before he was satisfied
that the theory expressed herein was
rhe correct one.

Projrrani of Annual Meeting
of the I. (). E.

The convention committee of the In-
stitute of Operating Engineers has ar-
ranged the following program for the
first annual meeting which is to take
place at the Engineering Societies build-
ing, 29 West Thirty-Ninth street. New
York City, on September I. 2 and 3:

Friday, September I, registration at
booth on main floor, 0 to 10 a.m.; opening
session in room 2. on the fifth floor, 10
a.m. The address of welcome will be

made by the Hon. William S. Bennett.
Short addresses will be made on "The
Operating Engineer's Future," by F. R.
Low; "The Engineer's Place in the Com-
munity," by D. B. Heilman; "The Em-
ployer and the Engineer," by A. C.
Dougall. At their conclusion various
committees will be appointed and in-
structed by the chairman.

The afternoon session will be called to
order in room 2 on the fifth floor at 2
o'clock. This session will be given over
entirely to the reading and discussing of
the following papers: "Temperature
Changes and Heal Transmission." by
Vernon L. Rupp; "Boiler-Room .^nalysi3
of Coal," by J. P. Fleming; "Cooling
Tow-ers versus Steam Pumps," by Henry
W. Geare.

The evening session will be called to
order at 8:15 in room 1 on the fifth
floor. Addresses will be made by Prof.
W. D. Ennis and F. H. Sykes, and an il-
lustrated paper will be given by J. A.
Pratt on "A Method of Teaching Operat-
ing Engineering."

At the 10 a.m. session on Saturday,
September 2, in room 2 on the fifth floor,
new business will be transacted, the re-
ports of the committees will be received
and discussed and the election of the
national officers for the coming year will
be held.

The afternoon session, at 2 o'clock in
mom 2 on the fifth floor, will be devoted
10 the following technical papers: "En-
cine Lubrication," by R. D. Toinlinson;
Reduction of Lubricating Costs in
Smelter Power Plants," by G. L. Fales;
"Removing Emulsified Oil from Con-
densed^ Water," by Darrow Sage.

In the evening at 8:15 a visit will be
made to the power house of the Inter-
borough Rapid Transit Company.

The program for Sunday, September 3,
has not been announced, but it is ex-
pected that the day will be spent in sight-
seeing trips about the city.

Ladif.s' Program

A committe to provide entertainment
on Friday for the ladies of the members
and friends of the Institute has arranged
for visits to the New York Public Library
at 10 a.m., and to Ellis island at 2 p.m.,
and a public mecling in room 1 on the
fifth floor of the Societies building, at
8:15 p.m.

For Saturday visits will be made to
the museums of Art and Natural His-
tory at 10 a.m., the botanical and zool-
ogical gardens in the Bronx park at 2
p.m., and the Interborough Rapid Transit
power house at S:I5.

On Sunday all who so desire may attend
the services at the Union Theological
Seminarv- at 1 1 a.m., or at the Cathedral
of St. .lohn the Divine at the same hour.

The committee consists of Mesdamcs
Jurgcnsen. Collins, Elder, Lawrence,
Eastment and Stewart and Miss Bjerre-
gaard.

346

POWER

August 29, 1911

New power House Equipment

Milne Superlieater

The Milne superheater, shown in the
accompanying illustration, is composed
of three simple elements: the dividing
wall above the arch, which forms a
duct to convey heat upward; the return-
hend tubes and the isolated chamber in
the upper drum.

The dividing wall is carried upon a
heavy I-beam independently of the fur-

Milne Superheater and Boiler

delivery of steam without undue fric-
tion or wire drawing. The superheater
tubes are expanded, metal to metal in
the upper drum, no screwed joints or
perishable material of any kind being
used.

No additional expense for masonry is
necessary. Suitable doors are located
in the upper part of the setting, which
allow access to the superheater tubes
for cleaning or repairs. A damper may
also be arranged in the duct to regulate
the volume of heat that may flow to
the superheater tubes or check it en-
tirely, if desired.

A similar form of superheater is used
in connection with the Milne multidrum
boiler, the design being practically the
same except that the duct is not re-
quired. The volume of heat allowed to
enter the superheater chamber may be
regulated by a swinging gridiron damper
located above the water tubes connect-
ing the upper drums.

This superheater is manufactured by
the Milne Water Tube Boiler Company,
30 Church street. New York City.

Double Service Feed Water
Heater

nace arch. The superheater tubes are
U-shaped. One end enters the upper
drum above the water line and the other
end enters the isolated chamber in the
same drum. This chamber has steam
a space suitable to the capacity of the
boiler and has a hinged swinging cover
closing the chamber, thus a convenient
means of access is provided.

A steam outlet or nozzle on the upper
drum connects the chamber and insula-
tion is placed about the steam drum for
protection against excess heat.

In starting the boiler the water line
is raised about one gage, thus flooding
the lower legs of the superheater tubes
and providing reliable protection against
overheating. When the required pres-
sure is produced steam is drawn off into
the mains, thus gradually lowering the
water line to the level required to pro-
duce the degree of superheat wanted;
then the feed valves are opened and the
water level and the degree of superheat
desired are maintained.

This superheater is very simple,
no flooding, draining valves or piping
being required, and any degree of super-
heat within reasonable limits can be ob-
tained. The superheater tubes are made
of extra-heavy special tubing to with-

stand excessive temperatures and at the The accompanying illustration shows

same time having mass and weight for a sectional view of a feed-water heater

heat storage in order to maintain uni- designed to keep the make-up water and

form temperatures. They combine at the condensate separate while passing

the same time suitable areas for free through the heater. It is manufactured

Double-service Feed-water Heater

August 29, 1911

POWER

347

by the Hoppes Manufacturing Company,
Springfield, O.

The heater is known as the "Class
H" or water-storage type. All of the
parts coming into contact with the feed
water are made of cast iron. It is
equipped with multitrough-shaped cast-
iron pans which, owing to their peculiar
design, bring the water on both sides
into direct and constant contact with the
exhaust steam and furnish a large heat-
ing and lime-catching surface.

The heater is also provided with a
large oil eliminator, skimmer overflow,
automatic regulating valve, and trap and
hooded suction. Its distinctive feature
is the arrangement for separating the
condensate and make-up waters until
after flowing over the pans. The
returns flow over the rear tier of pans
and the make-up water over two or more
tiers of pans in the front end of the
heater. This brings the collecting pans
to the end of the shell next to the re-
movable head and permits these pans
to be easily removed for cleaning with-
out disturbing the pans over which the
condensate passes. The hot and purified
make-up water and the heated returns
unite in the storage chamber at the bot-
tom of the heater shell and are pumped
thence to the boilers.

Dallett Pneumatic Boiler

Scaler
The Dallett pneumatic boiler scale, de-
signed to scale the shell and drums of
steam boilers, is, in fact, a pneumatic
hammer, striking rapid, light, uniform
blows at the rate of about 3000 per min-
ute. Air is admitted through the inlet
at the upper end of the tool and the
work is produced by the piston striking
the chisel which is inserted at the lower
end. This tool removes the hardest scale

Fic. 1. Operator Using Boiler Scaler

Tight down to the sheet, but it will not
injure the plate. The scale is not cut
or chipped off, as the light rapid blows
of the piston against the chisel and the
vibration caused thereby crack the
scale from the shell.

The tool is held against the sheet with
one hand. It is very light, weighing only
27 ounces, and the operator could hardly
get in a position where its use would
be inconvenient. Simple and durable. Its
operation can be readily understood by
referring to Fig. 1.

All wearing surfaces are carefully

hardened, and there is but one moving
part, the piston.

There is a locking spring at the lower
end of the tool for holding the chisel in
place while it is being used. The end
of the spring snaps into a groove on
the chisel shank, thus preventing the

Fig. 2. BoiLKR Scaler and Scaling Tools

chisel from flying out when the tool is
in operation. Its application is not con-
fined to the interior of the boiler, as it
can be used for cleaning scale from
pipes, condensers, heaters, etc., or
wherever there is an accumulation of
scale that can be reached with it.

not used, a small air-compressing out-
fit will be necessary.

With each tool are furnished two chisels
which are blunt on the end to prevent
cutting or injuring the sheet, but pointed
enough to effectively crack the scale;
they are shown in Fig. 2.

This tool is manufactured by the
Thomas H. Dallett Company, Twenty-
third and York streets, Philadelphia,.
Penn.

New Type of "Diamond"
Soot Blower

Herewith is illustrated an improved
soot-blowing device for use on the vari-
ous types of horizontal water-tube boil-
ers. It is manufactured by the "Dia-
mond" Power Specialty Company, De-
troit, Mich.

A striking feature of this blower is
the swivel joint B, upon which the noz-
zle jets are swung in and out of the
cleaning holes. This makes it possible
to keep the blower, when not in use, en-
tirely on the outside of the boiler, where
it is away from all possible injury by
the heat.

Us operation is extremely simple, as

Dia.mond Soot Blower

In a plant equipped with an air com-
pressor, the use of this boiler scaler will
not necessitate any change in equipment,
as the air consumption is but 4 cubic
feet per minute. In plants where air is

it consists of merely removing the clean-
ing door, swinging the nozzles in place,
opening the valve and slowly turning
the handwhecl until It has made one
complete revolution.

348

POWER

August 29, 191 1

National Convention of the
N. A. S. E.

On September 11 to 16, at Cin-
cinnati, O., will be held the twenty-ninth
annual convention of the National As-

The transportation committee, Messrs.
Coe, Paulson, Brainerd, Kaley, Durkin,
Penney and Cole, is making every effort
to gather a large delegation for the spe-
cial train and cordially invites all the
delegates and their friends to travel by

Music Hall, Where Convention Is to Be Held

way of the special if possible. The com-
mittee assures them all a royal good
time.

Convention Program

At nine o'clock Monday evening the
usual reception of the National and State
delegates will be held at the Sinton hotel.

The delegates and visitors will meet
at the Sinton hotel at nine o'clock on

sociation of Stationary Engineers. The
Sinton hotel has been selected as the
association's headquarters and the con-
vention will be held at Music hall. The
national convention will be held conjoint-
ly with the Ohio State convention, which
takes place on September 10, 11 and 12.

Arrangements have been completed
with the West Shore railroad for a spe-
cial train to Cincinnati. The train will
include a buffet and library smoking car
and sleeping, dining and observation
cars.

■Leaving the Desbrosses station at 2:40
on Sunday afternoon, September 10, the
train will stop at various points on its
way to Buffalo (arriving in Buffalo at
3:30 a.m.) for the delegates and their
friends who desire to board it nearer
their homes than New York City, and
will arrive in Cincinnati on Monday after-
noon, September II, at one o'clock.

The fare from, New York to Cincinnati
one way will be $13.50 on the party
basis; the Pullman rate will be S4 for
a double berth, ,$7.20 for a section and
SI 4 for a drawing room. The delegates
may purchase return tickets at Cin-
cinnati for parties of 10 or more at re-
duced rates or individual tickets at regu-
lar rates, which permit stopovers at
Cleveland, Buffalo, Niagara Falls, Roch-
ester, Syracuse, Utiea and Albany with* Tuesday morning and march to the con-
a 10-day limit at each of the above cities, vention hall. lohn A. Kerlev, chairman

ber of Commerce, and Charles H. Wir-
mel, State labor commissioner, will also
speak, responses being made by Edward
H. Kearney, national vice-president, and
William J. Reynolds, past national presi-
dent, respectively.

At twelve o'clock the convention will
be formally called to order, and at 12:15,
E. H. Kearney, national vice-president,
will officially open the exhibits. The
first session of the convention begins
at two o'clock, at which time the Ladies'
Auxiliary will convene at the Sinton
Hotel hall. The annual meeting of the
life and accident department will be. held
in the hotel hall at seven o'clock p.m.,
followed by an entertainment in Music
hall.

On Wednesday the day will be given
over to visits to interesting places of
amusement in and around Cincinnati,
ball games, bowling, etc..

The second session will be held at
nine o'clock Thursday morning, followed
at ten o'clock by the second session of
the Ladies' Auxiliary. Annual memorial
services occur at 1 1 :30 a.m. The third
session is at two o'clock, and at eight
o'clock p.m. an entertainment will be
given by the National Exhibitors' As-
• sociation at Music hall.

At nine o'clock on Friday morning rhe
convention convenes for the founh ses-
sion, and will hold its fifth and last ses-
sion at 2 p.m.

A public installation of officers, fol-
lowed by a grand ball, will take place
at the Sinton in the evening.

The entertainment committee will
do all in its power to make the

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Executive Committee, N. A. S. E.

standing, left to right : .Tohn
thairman : .Tolin E. Brunei-, vici
I'liai-k's Ij, Wilson, treasurer;

Applications for sleeping-car reserva-
tions should be sent to James R. Coe,
chairman of the transportation com-
mittee, 21 Maiden lane. New York City,
as soon as possible. All space will be
assigned in the order in which applica-
tions are received.

of the local committee, will call the as-
semblage to order. Governor Harmon
will deliver the address of welcome to
the State and Mayor Schwab will follow
with the city's welcome. National Presi-
dent Carl S. Pearse responding.

Walter Draper, president of the Cham-

Sitting, left to right: Frank Boyer, John
T. Schuller : .Toseph .T. Ahlers. secretary : John
M. Wiruiil. assistant secretary.

Stay of the delegates in this wideawake
city pleasurable as well as profitable.

Attention is called to a number of in-
teresting articles in this issue on vari-
ous power plants operating in the con-
vention city with the hope that they
may prove of practical value and incite
delegates to find time to personally in-
spect these plants where possible.

August 29. 1911

POWER

Increased Water Supply for
Pittsburg

The city of Pittsburg has recently
awarded contracts for the equipment for
the new Aspinwall pumping station
which, when completed, will add 100.-
000,000 gallons per day to the water
supply. The new station is to be
erected at Aspinwall near the site of
the filtration plant, and will eventually
contain five 20,000,000-gallon pumping
engines but only four of these will be
installed at the present time.

At one end of the station will be placed
t*'o triple-expansion pumping engines
with steam cylinders 32, 60 and 94
inches by 66 inches stroke. The water
ends are designed to deliver 20.000,000
gallons of water tvery 24 hours against
a head of 275 feet when the steam ends
receive steam at 160 pounds pressure
and 100 degrees superheat.

The duty guarantees on these engines
are the highest ever made, the guarantee
calling for a duty of 195,000,000 foot-
pounds per 1000 pounds of steam.

At the opposite end of the building
two new water ends, similar to those of
the units already mentioned, will be
placed. The steam ends of these units
will be the Holly engines now in the
Montrose station which are to be dis-
mantled and reerected on the new water
ends. There will remain space in the
center of the station for a fifth unit
which can be installed when needed.

The new pumping engines will take
their supply from a suction line run-
ning under the boiler room and parallel
to the engines and will discharge into
the Montrose rising main which sup-
plies the Troy Hill reservoir. At some
future time the water from this station
will be delivered to the proposed new
Cannage Hill reservoir. The contract for
the entire pumping equipment has been
awarded to the Allis-Chalmers Company
for approximately S300.000.

The Franklin Institute

To promote a correct knowledge of the
physical sciences and their proper appli-
cation in the varied fields of industrial
activity, has, since 1824, been the pur-
pose of the Franklin Institute of Penn-
sylvania. A brief resume of what it has
accomplished since that early date should
prove of interest.

In 1824 the Institute held the first ex-
hibition of American manufacturers, and
classes in chemistry, mechanics, natural
history, architecture, mathematics and
drawing were established. There were
304 pupils in attendance in 1826.

During the succeeding years the work
was srcatly extended and the Institute
was asked to conduct experiments and
investigations that were of much value
to the national Government. Committees
were appointed to inquire into the causes
of boiler explosions, the efficiency of

wa.ter as a motive power; systematic
meteorological obser\'ations were begun,
and a system of weights and measures
reported on, and investigations were
made of the strength of materials, ap-
paratus for testing steam boilers, metals,
building materials, etc.

As a result of its recommendations the
machine builders throughout the United
States adopted a uniform and simplified
system of screw threads; and a few-
years later the United States Govern-
ment officially adopted the "Franklin In-
stitute Standard," which is now in uni-
versal use. The Institute's suggestion
that the hundredth anniversary of the
United States be commemorated resulted
in the holding of the CentenniaJ Ex-
hibition of 1876.

Through its committee on science and
the arts during the past 20 years the
Institute has investigated over 900 dis-
coveries, processes and inventions in the
fields of the physical sciences, geology,
mechanical engineering, electrical, civil
and sanitary engineering, the textile and
leather industries and many other fields.

Its library in Philadelphia is probably
the most complete in America for works
on scientific and technological subjects
and can be freely consulted by anyone
interested in manufacturing and indus-
trial activities.

Low Water Causes Explosion

On Monday morning, August 14, a
boiler exploded at the mill of the Para-
gon Paper Company, Eaton, Ind., kill-
ing the night fireman and the coal passer.
From what can be learned, it seems that
the boiler, which was one of a batter>' of
five, was allowed to become entirely
empty of water and as the shell became
red hot the pressure of the steam from
the other boilers with which it was con-
nected ruptured this one.

As the mill was shut down over Sun-
day and the explosion took place early
Monday morning, it is supposed that the
steam pressure was being raised pre-
paratory to starting the week's work.

The rupture was along the bottom of
the front course and the reaction of the
outrushing steam lifted the boiler from
its setting and dismantled the one ad-
joining.

PERSONAL

Gano Dunn, who for some years has
been first vice-president, chief engineer
and a director of the Crocker- Wheeler
Company, has resigned from that com-
pany in order to accept an important
erpinecring and executive position. Mr.
Dunn will sail shortly for Europe to at-
tend, as president of the American In-
stitute of Electrical Engineers, the meet-
ing during the Turin exposition of the
International Elcctrotcchnical Commis-
sion, to be held on September 7, 8 and 9,

and also the following meeting of the
International Electrical Congress.

Prof. O. P. Hood, head of the depart-
ment of mechanical and electrical engi-
neering at the Michigan College of
Mines, has been appointed chief me-
chanical engineer of the United States
Bureau of Mines. Professor Hood will
leave some time in September and make
his headquarters in Pittsburg. For
thirteen years he has been with the
Michigan college and during that time
has been recognized as an authority on
practical mechanical and electrical engi-
neering subjects. As a consulting en-
gineer he has previously served the
bureau and has been employed at one
time or another by practically every
active mine in the copper country. Prob-
lems in fuel will be Professor Hood's
more immediate work.

•SOCIETY NOTES

On September 27 to 30, the semi-
annual meeting of the National Associa-
tion of Cotton Manufacturers will be held
at the Equinox house, Manchester, Vt.

Addresses are expected from Hon.
James Wilson, Secretary of Agriculture,
Prof. Henry C. Emery, chairman of the
Tariff Board, Hon. John Wingate Weeks,
member of Congress from Massachusetts,
and George W. Neville, president of the
New York Cotton Exchange. The full
program will not be issued until the
meeting, but papers of interest to Power
readers are expected on the following
subjects: "Alinement of Shafting and
Machinery," "Cleaning Machinery by
Compressed Air," "Conservation cf
Water Powers."

On August 10, at the hall of the
Beacon Association, National Association
of Stationary Engineers, Cambridge,
Mass., two of the most prominent mem-
bers were tendered a reception in recog-
nition of the work each had done for
the association. About ISO members of
Beacon Association, several national and
other officers, and many individual ad-
mirers of State President James H. Sum-
ner and Past President Thomas Ray, met
upon the occasion and by their presence
expressed the high respect in which both
officers are held. An excellent program
was given, and speeches were delivered
by Past National Presidents P. Henry
Hogan, Herbert E. Stone, Theodore N.
Kelsey; National Vice-president Edward
H. Kearney, Massachusetts State Vice-
president Thomas J. Maloney; President
C. D. Allen, of the New England As-
sociation of Commercial Engineers, and
Thomas P. Burke, of Providence, R. I.
Past National Presidents Kclscy and
Stone presented to Messrs. Ray and
Sumner respectively, a seal ring and a
meerschaum pipe. Mr. Ray was pre-
sented with a past president's jewel.

POWER

August 29, 1911

Moments with the

ii^ ^ s S s -V a. if.

The pyramids of Eg>'pt
form one of the seven won-
ders of the world.

They were built by the
kings as tombs and as ever-
lasting monuments of their
own greatness.

Only a few years ago did we begin to learn
why they were built and what the numer-
ous carvings and writings meant.

They were boastful stories of the great
deeds performed during the life of the king
and as such they give us a more or less hazy
idea of Egypt as it was thousands of years ago.

The record, however, was ven,- incomplete.
It told of the wonders they accomplished
and there is still plenty ot evidence of the
facts.

But the way they did them is still the
deepest mystery.

Of the pyramids there are in all about
seventy. The size of the Great Pyramid
is appalling when we consider the times in
which it was built.

Think of this one pile of stone containing
90,000,000 cubic feet of solid masonrvl It
is 480 feet high and 764 feet square at the
base.

It is estimated that it took 360,000 men
20 years to build it.

Some of the stones are so big that we have
no machines today powerful enough to move
them. '

They were handled by machinery of some
sort, however, for the marks are still plainly
seen after so many centuries.

This Great Pyramid stands exactly on
the 13th parallel of latitude, and its four cor-
ners point exactly to the four cardinal points
of the compass.

But how did they do it?
How were those enormous
stones set in place?

How did they harden coj>-
per and brass?

How did they make their
wonderful dyes?

There are no records to show. These arts
are lost — and lost completely.

The methods ot Eg>'pt died because there
was no way to record them. Printer's ink,
the great preserver, was not known. And so,
while the accomplishments of Eg>'pt were
mighty, thev were only useful for a lirnited
time and restricted to a limited area and a
comparatively few pyecple.

Today, through the medium of engineering
papers, modem methods of doing things are
being faithfully recorded and spread broad-
cast. They are being advertised to a world
which makes use of them.

If Egypt, wise and learned, had left records
far less perfect than those in just the
advertising section of this paper, we would
be going on where she left off. We would
be using their advanced knowledge.

There are men today who are doing big
things in the power plant field. Their deeds
are written in improved machinery and
recorded in the Selling Section

In the gradual development of better
methods and machines, we sometimes lose
sight of the tremendous significance of this
progress. Too many lose sight of progress
itself and these are they who contemptuously
refer to the Selling Section as "mere adver-
tising."

Advertising? Yes, you can gamble it's
advertising.

But, by the same token, it's a record of
current events of our own history' that none
of us can afford to overlook.

Vol. 34

NEW YORK, SEPTEMBER 5, IQll

N... 10

THE state of exaggeration will ever try
to beat the state of real achievement.
It has been at it for centuries, but al-
ways loses out. Exaggeration draws atten-
tion for a time, but its life is limited; the
bigger the boast, the smaller the assurance
of tact, and, directly, the shorter its existence.

Exaggeration in a marked degree becomes
a parodv, a parody of an imaginary original.
Just think this out, and the absurdity will
be evident. It is like setting up an engine
without a foundation.

This state is always found in the fellow
who likes to "put it over" the other cha]);
who believes he is "it" in his own mind and
wants to thoroughly impress you with the
big "I am." Vou have met him; does he
succeed ?

Real achievement is scarce, because it takes
a real man's work to get there. It is founded
on bedrock, it needs no introduction, it de-
mands no boost or assistance. The matter
is in actual evidence, its life is unlimited.
A real achievement endures perpetually.

In our little field in this world, the power
plant, the ratio of the achiever to the exagger-
ator is one to a hundred. Are you the one?

Even with this advantage in number of
followers, the old "brago" falls behind in
the race. He has no firm footing on which
In rest. The one is like an Oklahoma cyclone
^t sweeps everything in its path; the hun-
dred seek the "cellar," the " 'fraid hole";
they hide

The state of exaggeration in the engineer
is the state of self-conceit, and self-conceit
has an established record for costing many
a man his job. Even after the "jolt" he
wonders why; he would not if he could
forget the "ego."

The persistent exaggerator is closely allied
to the persistent prevaricator — he tells the
same yarn so often, and adding each time,
he gets to really believe it himself. He
always deals with past performances, and is
strong on anecdotes with the pronoun "1."

Get him down to facts, to present-day
realities. There's a diflercnce. Speak, for
instance, of economical fuel consumi)tion
and note the answer. His boilers are run-
ning and suj)plying steam, is not that enough?

.Mret the achiever, he is a good man to know.
If vou reallv want to "get there," just follow
him.

He is a man of character, of grit, has a tirm
determination to win, and all minus the
"swelled head " and the ever-beaten state
of exaggeration. His plant shows it. He
is "next" to real doings, actual o])eration;
he knows his business frotn firing to delivering
to the l)oar(l, and he docs not have to Icll it.
either.

To achieve is to win. and to win wc must
ever play honest. It is the liontst game
in life thai coiuils.

Let vour work be a real achievement.
It is bound to pav dividends.

POWER

September 5, 191 1

Southern California Edison System

The fact that the Southern California
Edison Company, of Los Angeles, is
building what will be one of the most
modern and economical central steam-
generating stations on the Pacific Coast
should revive the general interest in the
extensive system of that company.

The new plant is located at Long
Beach where sea water is available for
condensing purposes. Long Beach is
about 20 miles almost due south of Los
Angeles. The ultimate capacity of the
plant may be as much as 120,000 kilo-
watts and the plant will eventually take
over the load which is now being car-
ried by the steam-generating station,
Los Angeles No. 3, which is located in
the city of Los Angeles.

The initial equipment will consist of
a 15,000-kilovolt-ampere Curtis vertical
turbine and eight Stirling boilers using
crude oil as fuel. The steam will be
generated at 225 pounds pressure and
receive a superheat of 125 degrees. A
complete description of this plant will
be printed as soon as the construction
has advanced far enough for photograph-
ing.

A fair idea of the amount of territory
covered by the Southern California Edi-
son Company's system may be gained
from Fig. 1. The dotted lines to the
north on the map indicate future de-
velopment. The distance between Kern
River No. 5, the most northerly of the
proposed water-power stations, and Los
Angeles is about 140 miles in an air line.
The distance between Upper Santa Ana,
the most easterly of the w-ater-power
stations, and Los Angeles is about 75
miles in an air line. These great dis-
tances between the generating stations
and the area of distribution are char-
acteristic of many of the water-power
systems in the far West.

The first hydraulic-generating station
of this vast system and the first three-
phase "high-tension" system to be used
in America was completed in 1893 at a
point about 8 miles east of the town of
Redlands in San Bernardino county. The
station is now known as Mill Creek No.
1. It contained at the time of its com-
pletion two 250-kilowatt three-phase gen-
erators driven by Pelton waterwheels at
600 revolutions per minute. The effec-
tive head was 295 feet. Current was
generated at 2500 volts and transmitted
to Redlands at the same pressure. Dr.
Louis Bell, who designed the plant, de-
cided upon 50 cycles as the proper cur-
rent frequency, following the lead es-
tablished by European practice, 25 cycles
for power circuits and the full 50 for
lighting.

It is interesting to note that as a re-
sult of Doctor Bell's decision in 1892
to use 50-cycle current all public-service
current in southern California today is

By A. R. Maujer

Historical and descriptive
sketch of an electric gene-
rating system which event-
ually will consist of some 1 2
hydroelectric plants ranging
in capacity from looo to
20,ooo kilowatts and tico
steam-generating plants of
which one has a capacity
of 11,500 kiloii'atts and the
other "will hare a probable
ultimate capacity of 120,-
000 kilojvatts.

50 cycles. When the first extensions
of the original system were made It

naturally followed that the dynamos were
wound for 50 cycles so as to be con-
sistent with the existing apparatus.
Later when the desirability of 60-cycle
current became manifest the system had
grown to such proportions that a change
over was out of the question. Then,
when the Pacific Light and Power Cor-
poration entered the field, in order to be
able to have an emergency tie-in with
the Edison Company's lines. It also
adopted 50 cycles.

In 1896 it became necessary to In-
crease the capacity of Mill Creek No. 1
and this was done by increasing the head
and adding a dynamo to the equipment.
At the same time three Wagner s-.atlc
transformers were installed to raise the
transmission voltage to 10,000 volts,
which at that time was considered to be
the ultimate In the way of high-tension
current possibility. The effective water-
pressure head was raised from 295 to
650 feet; this necessitated an Increase
of 3000 linear feet in the length of the
pressure pipe, making the total length

Fig. 1. Map of the Southern California Edison Co.mpany System

September 5, 191 1

POWER

353

10,250 feet. This increased the capa-
city of the station to 650 kilowatts. All
of the old waterwheels were taken out
and new ones, designed to operate eco-
nomically under the new head, were put

1903. The static head is 1960 feet.
Since Mil! Creek No. 3 was built one or
two plants of still higher head have
been put up. The Pike's Peak plant has
a head of something over 2000 feet.

Mill Creek No. 2 with Addition Known As Mill Creek No. 3

in. Water for the wheels which drove
the new dynamo was tapped out of the
existing pressure pipe.

Santa Ana River Development

In the latter pan of 1898 the Santa
, Ana River Station No. I, to the north of
the Mill Creek plant, was completed.
This station contains four 750-kilowatt
General EJectric dynamos, of which three
are driven by Pelton impulse waterwheels
and one is driven by a Doble impulse
wheel. The speed is 300 revolutions per
minute and current is generated at 750
volts. Originally the plant had but one
pressure pipe, but later a second pipe
was put in for emergency use. The head
is 760 feet and there are 2285 lineal feet
of pressure pipe. In addition to this
•here is considerable wood flume work
keep in repair and some tunnels.

Mill Creek No. 2

In 1899 further prowth in the demands
for power resulted in the erection of
Mill Creek Station No. 2, two miles east
of the No. I station. Here there was in-
stalled two a-^O-kilowatt 11,500-vnlt
three-phase General Electric dynamo--
driven by Pelton impulse wheels at 375
revolutions per minute. The water-pres-
sure head at this station is 627 feet.

Mil l Creek No. 3

The next extension to be made was
called Mill Creek Station No. .3. althouEh
actually it was only an addition to Mill
Creek No. 2 and not a separate station
at all. Mill Creek No. 3 had the highest
head of any hydraulic power plant in
America at the time of its erection in

Mill Creek No. 3 contains four 750-
kilowatt dynamos which generate current
at 750 volts. Of these, three are driven
by Doble wheels and one is driven by a
Pelton wheel. The speed is 430 revolu-
tions per minute.

Mill Creek No. 2 it is 627 feet. All
excitation for Mill Creek Nos. 2 and 3
is generated by half of the water sup-
plied to No. 2; the remaining half drives
one of the original waterwheels to which
has been attached a new 250-kilowatt
dynamo.

The pressure pipe for the Mill Creek
No. 3 station is 8096 feet long and 26
inches in diameter, reducing to 24 inches
at the bottom. Fig. 2 shows the exterior
of the combined Mill Creek Stations Nos.
2 and 3 and Fig. 3 shows the four units
which are known as Mill Creek No. 3.

Santa Ana No. 2

In 1905 the Santa Ana Station No. 2
was completed. It contains two 500-kilo-
watt General Electric dynamos driven
by Doble wheels at 176' _. revolutions
per minute and generating current at
750 volts. The head is 310 feet and
the pressure main is 644 feet long and
36 inches in diameter. There are 7507
feet of tunnel and 2136 feet of siphon
pipe. This plant has no flume work.

Kern River No. 1

The latest and largest of the water-
power stations of this system, known
as Kern River No. 1, was put into service
in May, 1907. This plant is about 100
miles nof^hwest of Los Angeles. It con-
tains four 5000-kilowatt 2300-volt Gen-
eral Electric dynamos driven by Alli»-
Chalmers impulse wheels at 2,^0 revolu-

Fir,. 3. Equipment Known As Mill Chi i

At the same time that Mill Creek No.
3 was being installed, the two dynamos
in No. 2 were taken out and moved to a
new station located a short distance
northwest of Colton and known as the
Lytic Creek Station. New waterwheels
were put on these dynamos as the head
at Lytle Creek is only 474 feet while at

tions per minute. The head is 784 feet
and there are 1425 feet of pressure main,
6 feel in diameter. To bring the water
to this plant, 44,935 feet of canal work
are required of which 42.911 feet are
tunnels and the balance wooden flumes.
The funnels are 8 feet wide and 7 feet
high to the spring of the arch.

354

POWER

September 5. 1911

Fig. 4. Kern Ri\tK SrATio.N No. I

Los Angeles No. 3. This unit runs at
750 revolutions per minute and generates
current at 16,500 volts.

Cooling Tower

Perhaps the most interesting thing
about the Los Angeles No. 3 station is
the cooling tower. This is built in two
sections; the first section was put up
when the station was built and the sec-
ond when the No. 3 unit was installed.
The tower is of the atmospheric type
and built of wood. The first section
covers a ground area of 9800 square
feet. The filling for both sections is
of vertical mats made of common wooden
laths. When both of the Curtis turbines
are in ser\'ice about 17.5 second- feet of
condensing water pass over the No. 1
section of the tower. The water falls 20
feet.

The No. 2 section covers a ground
area of 7490 square feet and contains
some 335.000 square feet of wetted sur-
face. In this section the water has a
fall of 28 feet. When the Parsons unit

Steam Auxiliary Station

As is the case with the big majority
of hydroelectric systems, the Southern
California Edison Company has a steam
auxiliary station. This station, which is
designated as Los Angeles No. 3, is lo-
cated in Los Angeles. Originally it
ser\'ed only as a relay in case of inter-
rupted service from the hydraulic plants,
but now on account of the rapid growth
in the demands for power part of its
equipment generates current even during
normal load conditions to piece out the
insufficient supply from the water-power
plants. When it is ready for ser\'ice the
new Long Beach station will take all of
the permanent load now carried by Los
.'Angeles No. 3 and the latter will then
be maintained purely as an emergency
reserve.

The first two units in Los Angeles No.
3 were put into ser\'ice in 1904. These
are 2000-kilowatt Curtis turbines driving
2300-volt General Electric dynamos at
750 revolutions per minute. The con-
densers for these units are Wheeler
Admiralty type. Originally each con-
denser contained 6000 square feet of
condensing surface but subsequently
3000 square feet were added. The cir-
culating-water pumps are single-stag2
centrifugal driven by 100-horsepower
motors. The condensate is handled by
Edwards triplex wet-vacuum pumps
driven through steel-rawhide gears by
30-horsepower motors.

Electrical drive was adopted for these
auxiliaries because in a relay plant sim-
plicity and reliability of operation are
of greater ultimate economy than ex-
treme efficiency with regard to fuel con-
sumption.

In the latter part of 1907 a 7500-kilo-
watt Westinghouse-Parsons turbo-gen-
erator was added to the equipment of

Fig. 5. Interior of Ker.n River Station No. 1

Fic. 6. Los Angeles Station No. 3, Shoviiing Part of the Cooling Tower

September 5, 1011

POWER

355

Fic. 7. Interior of Generator House of Los Angeles Station No. 3

is carr>'ing its maximum load 33 second-
feet of water pass over the tower.

A recent test of the No. 2 section
showed that under maximum-load condi-
tions, with the condenser-discharge water
going to the tower at 108 degrees, the
temperature of the atmosphere at 65 de-
grees, and with a humidity of 60 per
cent, the circulating water was cooled to
89 degrees and 140,500.000 B.t.u. were
dissipated per hour.

Boilers

The boiler installation for the first two
tinits consists of eight 500-horsepower
Stirling boilers, each containing 5020
square feet of heating surface and 702
square feet of superheating surface.
Steam is generated at 150 pounds and
given a superheat of 125 degrees.

Seven 750-horsepower Stirling boilers
were installed to supply steam to the
Westinghouse-Parsons unit. These con-
tain 7512 square feet of heating surface
and 1600 square feet of superheating
surface. They generate steam at 170
pounds pressure and give a superheat of
l.SO degrees.

Crude oil is used for fuel, fed through
Leahy back-shot fuel-oil burners. One
stack furnishes the draft for all of the
boilers; it is 150 feet high, 12 feet in
diameter. The stack is built of rein-
forced concrete, and is of the plumb-wall
doiihle-shcll construction.

The feed pumps for the first boilers
are Dean duplex, outside end packed,
10 and 6 by 12 inches in size. The pumps
for the newer boilers are Snow duplex,
outside center packed. 16 and 10 by 12
inches in size.

The boiler makeup water is raised
from a well on the property to wooden
treating and storage tanks by a 6 and
5\i by 6-Inch Dow duplex pump. The

carbonate and sulphate impurities in the
water are neutralized with compound
manufactured by the company itself.

A 500-horsepower Cookson open feed-
water heater serves the original boilers

and a 5000-horsepower Cochrane open
heater serves the other boilers.

Current Distribution
Los Angeles Station No. 3 serves as
the receiving station for the current from
the water-power plants. The current
from the Kern River station is brought
into Los Angeles No. 3 at 75,000 volts
where it is stepped down for local dis-
tribution. The distribution voltages in
the city of Los Angeles are 15,000 and
2300 volts.

The transmission voltage from the
Mill Creek and Santa Ana groups of sta-
tions is 30,000 volts. The current from
these stations is sent toward Los Angeles,
supplying the various towns along the
route. During normal-load periods there
is a surplus which is received at Los
Angeles No. 3, but during maximum-de-
inand periods there is a deficiency which
is made up from the current generated
in Los Angeles No. 3. Practically all
of the current generated at the Lytle
Creek plant is consumed in Colton, 8
miles away. The transmission from
Lytle Creek is at 11,000 volts.

We are indebted to R. J. C. Wood,
superintendent of generation, for particu-
lars in regard to the equipment of the
various st.itions described herein.

i\ N I . H I V ^1

356

POWER

September 5, 191 1

Increasing Efficiency of Rotary Pumps

During a trip abroad, fro-n wliicli the
writer recently returned, he was par-
ticularly interested to obseive the pro-
gress being made in the development of
rotary power and pressure machinery,
including steam turbines, pumps, com-
pressors and blowers; and in the fol-
lowing will be found the account of an
invention affecting all of these. It
originated, however, with centrifugal
pumps, and has thus far been worked
out along that line only, except as noted
farther on.

To anyone familiar with such pumps
it is well known that their development
has been a matter of constant experi-
menting, in the course of which rea-
sonably accurate rules and formulas
have been evolved to cover most of the
details of construction; so that now the
exact contribution which will be made
by any part to the efficiency of the unit
as a whole can be very closely deter-
mined in advance. Throughout the de-
sign the purpose has always been to
reduce as far as practicable the fric-
tional resistance of the water and other
disturbing influences, thereby converting
into pressure as large a proportion as
possible of its kinetic energy which
arises from the velocity given to it by
the impeller.

Among later improvements the most
important has unquestionably been the
general adoption of diffusers so designed
as to form passages leading from the
rim of the impeller to the volute, or
whirl chamber, the effect of which will
be to prevent the formation of eddies
and to make the entrance of the water
to the volute less of an interruption to
its flow.

On the Continent, where the centrifu-
gal pump has developed faster prob-

By C. A. Tupper

The use of rotating difjusers,
invented by Professor So-
vak of Atislria, has been
found to increase centrifu-
<^(il f>U)np ejfifiency. 1 Ik
idea is also applicable to
turbo-blowers and compress-
ors.

in practice, h\' constructing a pump with
rotating diffusers which he has covered
by basic patents.

This pump is comparable with the
well known Rateau type, but differs from
it in that the diffusers are not fixed but

of the friction at both sides of the im-
peller, and provision for an ample whirl-
pool or diffuser space with least side
friction.

The diffuser may consist of one or
more shells rotating separately. Its ac-
tion, or the changing of the kinetic en-
ergy into pressure, is accomplished by
the lips or sides of the outer edge of
the rotating parts. These are so shaped
as to form an easy passage from the
impeller to the volute. The diffuser
shells revolve freely on their axes and
the action of the water issuing from
the impeller keeps them in motion.
Naturally, due to friction of the disks
themselves and the decreasing velocity
of the water, there is a gradual less-
ening of the peripheral velocity of these
revolving parts as their distance from
the impeller is increased. In this way
the velocity of the water is gradually
stepped down. Bearing this in mind, it

T.VBLE 1. RESULT.S OF TESTS OF S.M.'VLL VOLUTE PIMP

Tfst luimber

Currt'iit consumption, kilo-
watt

Hcvolutions per minute of
motor

Efficiency of motor, per
cent

Delivery of motor, horse-
power

Power consumed by belt,
estimated liorsepower. . .

Power consumed by pump,
horsepower

Revolutions per minute of
pump

Manoraetric head, meters. .

Capacity in liters (weir
measurement)

Dehver.y of pump, horse-
powder

Efficiency of pump, per
cent

1.0.5
1042

2.0

1000

33

0.92

0.3

0.62

2220
0

2.07

1000

35

0.985

0.3

0.6S

2220
0

2 . 31
1030
39
1.2-1
0.3
0.94

2260

.5.4

0

60

4.16

0.3

3.86

2200
16.6

8.15

1.805

46.8

5.47

950

61

4.55

0.3

4.25

2000
15.1

9.65

1.945

45.8

2.44
1040

39

1.293

0.3

0.995

4.39
980
59.5
3.55
0.3
3.25

2.15
66.2

4.02
0.3

10.32
2.40

N(;>TE. — Rotating difTuser = R. Stationary ditTuser = F. H.P. = Metric horsepower, or slightly
tlian the t'nited States horsepower standard.

Fig. 1. Volute Pump Fitted wtth Rot.^ting Diffuser

ably than in this country, one of the so arranged as to be freely rotated upon is easy to see that the ratio of velocity

most eminent designing engineers, Prof, the shaft of the impeller or upon a spc- existing between the water and the re-

J. Novak, of Prague, Austria, has gone cial rigid sleeve. volving diffusers is much less than that

a step farther, if the conclusions drawn As a result of this arrangement there produced by the stationary diffusion

in this article are fully substantiated are two decided advantages: Reduction vanes ordinarily used, and with this re-

September 5, 1911

POWER

357

duction in the relative velocity there is,
of course, a very appreciable lowering
of the frictional losses.

Table 1 shows the results obtained

The initial test was corjMcted by di-
rector E. G. Fischinger, a consulting en-
gineer of Dresden, in the interest of the
machinery-building and engineering com-

Manometer

Fig. 2. Arrangement for First Test

!th the small volute pump represented
n Fig. 1, which was the first to be built
and which was intended only for experi-
mental purposes. This pump had a 3'/<-

pany, Rudolph Meyer Aktien Geselschaft,
Mulheim-on-the-Ruhr, which took over
the entire patent rights for Germany of
the Novak invention.

was held stationary by an especially pro-
vided pin inserted for the purpose. In
those marked R the diffuser was per-
mitted to rotate freely.

The conditions existing in the opera-
tion of a modern centrifugal pump were
by no means reproduced merely by hold-
ing the diffuser stationary, as the re-
sults of the teS'S themselves show; but
the pump was no; intended to do more
than to indicate the relation between the
efficiencies to be obtained from fixed
and rotating diffusers. . As a specimen
of pump construction it k^t much to be
desired, having been built in a plant
not adapted to that class of woik. Even
the rotor was not well balancea, thus
rendering its movement very uneven.

Later, another pump b lilt by Rudolph
Meyer, Inc., was subm"tted to tests
These took place in the vorks of th;it
firm at Mulheim-on-the-Runr, under t'le
general direction of Messrs. Kwaysser
and Saloman, an engineer in 'ienna and
an engineer of the Meyer fir. ', resp?c-
lively, as well as in the pri=;ence oi
Professor Novak.

This pump had an impeller 14 inches

RESULTS OF .SECOND SERIES OF TE.STS

Test .Vo

Diffuser ffixed or rotating)

t^ p.m. of pump

' ' inometnc head, meters ,

>;>acit.v JMT s»*cond

.•iisumption of current.

i,ilowatts

ilolor delivery, kilowatts.
Pump delivcrj-. kilowatts.
Efficiency of unil, per cent.
K'ticicncy of pump with

'■•■It. per cent

'iriency of pump alone,

:"'r cent

i! Iraulic efBciency, per

27.2 27.45 32.1

Rotating
1412 1400
.52.79 53.29

27.8

.0

51.0 53.5
56.4 59.5
60.0 62.0

16.5
55.4

62.0

■8.0 82.0 82.0 80.0

29.0
26.0
16.9
58.3

65.0

69.0

84.0

1390 138(

50.82 41 7(

37.0 47.2

31.0 37.0

.58.4
63.4
68.0

Fixed

1412 1380
41.39 34 6

19.6 23.9

22.8

7.9

31.0

34.6

37.6

25.0
9.7
34. S

38.9

42.0

63 0

43 2
36 4

48.0
56.0

ROT.^TING

1010 1000
!2 02 25.14

US
10.0
6.32
54.0

1000
23.05
38. a

13.5
11.9.
8.65
64.0

73.0

76.0

72.5

11.5
9.8
3. 88

33.0

39.6
43.0
52.0

9.8
4.25
37.0

43.5

47.0

58.0

lot:
17.83
30.2

40.75
47.0
50.0
52.0

ch discnarge, with two balanced suc-
ins of about 2Vr inches diameter each,
■ :c impeller diameter being about 5>i
:;ches. The unit was designed to de-
liver 9 liters of water per second, or the
equivalent of about 140 gallons per min-
ute.

It will be noted from Fig. 1 that the
pump had a single rotating diffuser and

^=a

y^Z ""^ ''^" '""

-Me'r.r ^o:

j;;!

^

Fir,. 3. Arrangement for SncoNn Test

I suitably designed throat. The shells
A the diffuser were held together by
Je bolts, which also assisted the im-
: ■ llcr discharge to drive the diffuser by
iriction along its inner surfaces.

The arrangement for the test is shown
in Fig. 2. A 13-horsepower direct-cur-
rent motor was belted to the pump and
the suction pipe was firmly secured be-
neath the pump. The water from the
suction tank which passed through the
pump was led through a tube 8 feet
long to an adiusiable discharge nozzle.
The discharge basin and suction tank
were connected by a flume at the lower
end of which a Francis overfall measur-
ing weir had been placed. Both the dis-
charge nozzle and the weir were used
in determining the volume of water
handled, but only the values found with
the latter, being somewhat lower than
those shown by the discharge nozzle, arc
entered in the table. For measuring the
.head there were used two recording
manometers, which were compared with
each other and the readings of which
agreed. In determining the consuit^plinn
of electric current and arriving at the effi-
ciency of the motor. Director Fischinger
used his own instruments, which prior
to the test had been carefully calibrated
according to the compensation method.

For the tests shown in the columns of
Table 1 that arc marked F, the diffuser

30

/"

1

h-

\^

^

,■4..

\*

\o

1 i\^

/»

M

==i'

.

' 1 %

^^ \

x<v

1 1 ix<a. 1

\

^1

1

45 50

20 25 30 J5

Li+res per Second

Fig. 4. Pomp Performance Shown
Graphically

in diameter. The arrangement for the
tests is shown in Fig. .1. The results
arc given in Tabic 2. From these tests
it was evident that better efficiencies
could be obtained by lessening the me-

358

POWER

September 5, 1911

1.^—

^c

^^^

,^^

-^ 1 ~1

<^^£::iS°^^mpr,on\

chanical losses, and two rings were taken
from the center bearing which had been
continually running hot.

For four hours on the following day
a third test was then run. During this
the manometer remained at a constant
hight, except for some slight fluctuations

70 5

Fig. 5. Efficiency and Current Con-
sumption Shown Graphically

caused by differences in the speed, and
a steadily increasing volume of discharge
was observed, with a lessening in the
consumption of electric current and a
rise in the efficiency, which reached 75
per cent. In Figs. 4 and 5 this is shown
graphically.

Since then additional pumps have been
built and the writer has been informed
that they are showing good results in
service; but their manufacture has not
yet reached the commercial stage as
Professor Novak is proceeding slowly in
the development of the various sizes and
wishes to standardize them before put-
ting the pumps on the market.

In the United States the simultaneous
development of the pump has been un-
dertaken by O. C. Goeriz & Co., of San
Francisco, Cal., who are just completing
their first unit, a single-stage house
pump, with double inlet, for 100 gal-
lons per minute delivery against 55
pounds pressure, or the equivalent of
120 feet head. This will run at 3400
revolutions per minute and is to be op-
erated by a direct-connected 5-horse-
power alternating-current (two-pole)
motor. Drawings for similar pumps of
50 and 150 gallons per minute are now
in course of preparation.

This firm makes interesting compari-
sons between a twin-centrifugal pump of
standard design, shown in Fig. 6. and a
similar pump redesigned in accordance
with the Novak system, as illustrated
in Fig. 7. The company says:

"It is known that the frictional re-
sistance between a revolving disk and
water depends on the squared relative
velocity, while the energy loss must con-
form with the cubed ratio of the rela-
tive velocity between the disk and water.
Applying this to a comparison of disk
friction for the pump shown in Fig. 6
as against that in Fig. 7. and assuming
that the runner in both cases revolves
with the same speed, the following con-
clusion can be reached: In the former
the water volumes B and C can be as-
sumed to run at half speed, which is the
middle between the full-speed runner
and the stationary side walls. The rela-

tive velocity, or difference between full
and half speeds, is therefore one-half
speed. In the case of Fig. 7 the diffuser
DE revolves at half speed itself, as
proved by the tests made with Novak
pumps; then the water volumes B and C
are churned with, say, three-quarter
speed, or the relative velocity is one-
quarter.

"For equal impeller diameters and
equal impeller speeds it would therefore
follow that, because the relative velocity
between the impeller sides and the water
in Fig. 7 is one-half that in Fig. 6, the
frictional resistance must be one-quarter,
and the loss of work by friction must
be only one-eighth of what losses occur
in the ordinary case represented by Fig.
6. The energy losses in chambers f and
G do not sum up with the losses in B
and C. What waste is going on in F
and C does not directly affect the en-
ergy required at the pump shaft. How-
ever, it influences the velocity of the
diffuser halves U and £ and thus indi-
rectly the waste going on in B and C.
The friction loss in B drives the diffuser

niKT

Fig. 6. Standard Twin-suction Cen-
trifugal Pump

and the loss in £ acts like a brake, but
both have to balance; otherwise the dif-
fuser must gain or lose speed until such
equilibrium of friction forces shall be
attained.

"This is one part of the Novak im-
provement. Contemplating the other and
more important innovation, the two
sketches. Figs. 6 and 7, must be com-
pared again.

"In Fig. 6 the water rushes from the
impeller at a velocity which, for the sake
of convenience, may be termed 'full
speed,' and along the walls F of the
stationary diffuser a certain part of the
energy contained in the water must be
dissipated by disk friction. The relative
velocity between water and side walls
is the entire full speed. Now, in Fig.
7 the walls K, which belong to the dif-
fuser halves D, and £, revolve again at
half speed, and the relative velocity can
be expressed as half speed. Therefore
the frictional resistance in the arrange-
ment shown by Fig. 7. as against that of
Fig. 6. assuming equal extension of the
diffuser walls in radial direction and
similar conditions of the surface, will be

one-quarter, making the loss of energy
one-eighth only."

The invention of Professor Novak is
adaptable either to a volute or a tur-
bine pump, and the selection of type de-
pends mainly upon the head against
which the water is to be delivered.

The considerable reduction of side
friction and the improved whirling ac-
tion in the Novak pump make it pos-
sible in many cases to run the impeller
at a higher rate of speed, and thus as
compared with a multi-stage unit to
perform the required service with a sin-
gle impeller without sacrifice of effi-
ciency. For example, a one-impeller
pump with the Novak diffuser can be
made to replace a four-stage turbine
pump of standard design running at half
speed. Such a single impeller, which
may require a casing of considerable
radial extension if surrounded by sev-
eral Novak diffuser shells, connected
with a motor running at higher speed,
will therefore be a strong competitor
of the low-speed (or even equal speed)
multi-stage turbine pump. Thus it will be
practicable to build pump units, includ-
ing higher-speed steam turbines designed
for the most favorable conditions of
steam consumption, with corresponding
benefit to the net efficiency in the latter
direction also.

The test results shown in the tables
indicate furthermore that an excellent
standard line of house pumps can be
developed at relatively low costs to give
high efficiency, thus putting them in the
lead of triplex pumps, as the latter re-
quire a number of gears between the
crank shaft and an electric motor op-
erating at lower speed.

For high-lift pumping, as in mines,
fire-protection systems, etc., the 100 to
300 pounds pressure attainable with
pumps built on the Novak design will

Fig. 7. Twin-suction Pu.mp Fitted with
Rotating Diffusers

offer additional opportunities for its ap-
plication.

Furthermore, it is apparent from Fig.
7 that the Novak type of pump can be
conveniently standardized, inasmuch as
even a considerable difference in service
requirements can be taken care of by
a slight alteration to the first revolving
diffuser, thus adapting the same size to
smaller or larger lifts.

September 5, 1911

POWER

359

Certain- mechanical improvements
which have been brought out hy the
American representatives of Professor
Novak, but which they state fall under
the domain of his basic patents, are in-
dicated on the right side of Fig. 7. Here
a bussing A^ is shown, which is loose on
the shaft but rigidly connected to the
Novak diffuser half £, either by vanes
O similar in shape to propeller blades or
merely by stays P, thereby supporting
the v/hole diffuser directly by the shaft
itself. By this alteration a material re-
di;ction of mechanical friction is gained.

Furthermore, if the water handled is
gritty, oil or grease can be readily fed
through a bore in the shaft directly into
the clearance between bushing N and
the shaft. In addition, provision has
been made, it is stated, to so construct
the impeller and diffuser that end thrust
is taken care of automatically.

"It is the logical inference," says Di-
rector Fischinger, who made the tests
first above mentioned, "that moving dif-
fusers will have an influence upon the
efficiency of rotary blowers and com-
pressors equally as great as that which

has here been established in relation to
centrifugal pumps. Should that infer-
ence be confirmed by practical tests, then
there will be a great future opened up
for the turbo-compressor."

Professor Novak is now working on
the application of his patent to air com-
pressors of the Rateau type, and some
interesting developments in this line are
expected to be announced shortly. Rud.
Meyer Aktien Gesellschaft have already
built and exhibited Rateau turbo-com-
pressors fitted with Novak diffusers and
are putting them on the market.

Water Power Dam at Keokuk

A large water-power project that has
attracted a great deal of attention
throughout the Middle West for some
time is that of the Mississippi River
Power Company, which includes a dam
across the Mississippi river between
Keokuk, la., and Hamilton, 111. The work
has now reached the stage where a good
idea can be had of the magnitude of
the undertaking.

The dam is being built at the foot
of the Des Moines rapids, which have
always constituted an obstruction to navi-
gation at this point except at times of
high water and around which the Gov-
ernment has maintained a system of
locks which was constructed in 1877.
The new dam will make the maintenance
of these locks unnecessary, as the power
company will build new locks of much
gi^ater capacity, and these will be fur-
nished to the Government free of cost.
The new locks will be designed for a
channel depth of 8 feet if the Govern-
ment decides on that depth in the river
channel. The dam will also furnish a
pennanent navigable stage of water for
a distance of 60 miles above.

Bv S. Kirlin

The dam is to be 32 feet
high ami nearly a mile
long. It 'aill be sur-
mounted by adjiistabli
steel flood gates 1 1 feet
high and the available head
ix'ill vary from 31 to 39
feet, rhe uiitial installa-
tion- of icateru' heels leill
have a capacity of 120,000
kilowatts, though the ulti-
mate capacity will be 220,-
000 kilowatts.

The dam, including abutments, will
have a total length of nearly one mile,
the spillway section being 4278 feet in
length. Its hight will be 32 feet above

the river bed and the width of the base
42 feet. The upstream face will be
vertical; the downstream side will be
curved, having an arc of a circle at the
toe whicii will throw the water away
in a horizontal direction. On top of the
spillway will be placed 119 steel flood
gates 30 feet wide and 1 1 feet high, sup-
ported by concrete piers 6 feet thick,
built integral with the dam. They will
also support an arched bridge from which
the gates will be electrically operated and
so manipulated that the water above the
dam will be maintained at practically a
constant level at all seasons of the year.
The dam will be built entirely of con-
crete, without any reinforcement, and
will be locked firmly in the river bed
which is formed entirely of solid blue
limestone at this point, making an ideal
foundation for this type of structure.
All work on the dam proper is being
done on the Illinois side of the river,
while the power house and locks ai^
being built from the Iowa side. Two
temporary power houses, one on each
side of the river, furnish the power for
operating all engines, pumps and other

Fir. I. 1 i*'' ^1 CTTON'- OF THI PdW I K-HHC vK C'lHhkROAM

360

POWER

September 5, 1911

machinery used on the works. The one
on the Iowa side contains 1000 horse-
power in boilers, one 350-horsepower
air compressor and one smaller coin-
pressor having a capacity of 150 horse-
power. An electric-lighting plant is lo-
cated in this power house in order that
the construction can go forward night
and day.

On the Illinois side the temporary
power house contains 800 horsepower
in boilers, these furnishing the steam
for operating all engines, pumps and
drills used on the Illinois side of the
river. An unusual feature of the work
is the use of compressed air in all ol
the engines driving the different appa-
ratus, the engineers deciding that this
would be the most economical consider-
ing the scattered position of a large por-
tion of the machinery to be driven.

The capacity of the concrete plant is
1200 cubic yards per day and involves
the moving of 100 carloads of rock, 50
cars of sand, 6 cars of cement and 100
trains of concrete per day. About 300,-
000 cubic yards of sand will be re-
quired to complete the work, which is
obtained by means of a large sand-
pumping plant located in the old channel
of the Des Moines river about two miles
below the dam. Great care is exercised
that all material is up to standard grade,
a complete laboratory being maintained
on the Illinois side for this purpose. Sam-
ples of the concrete mixture are taken
at frequent intervals from the buckets
which convey the material to the forms.
AH cement is carefully tested by the
company's representative at the mills be-

located entirely in the bed of the river
on the Iowa side. The power house
will be 1400 feet long and 123 feet
wide, and it will extend at right angles
to the dam. The substructure will be
of massive concrete in which will be

sary to blast out of the bed of the river
in locating the foundations for the power
house and lock is almost exactly the
amount needed in the concrete work of
the entire structure, including the dam,
power house and lock. This rock, after

Fig. 2. Looking toward Iowa Shore

molded the water-wheel chambers and
passages leading to them. On top of
this will be built the superstructure, of
concrete, brick and steel construction; it
will contain the generators, transform-
ers and switchboards. There will be 30
vertical generating units; the generators

it is blasted out, is loaded into cars by
means of steam shovels, transported to
the crushing plant and when crushed is
conveyed to the bins over the mixing
plants located on each side of the river.
To prevent floating ice, logs and other
objects from entering the channels lead-

Fic. 3. Looking toward Ilijnois Shore

lore it is shipped to the warehouses at
the works. All stone used in the con-
crete is blasted out of the river bed
in making the foundations, and is of the
finest quality.

The power house and locks will be

will be mounted on the upper end of
the shaft and each shaft provided with
two turbine wheels at the lower end.
The hight of the power house from the
foundation to the roof will be 133 feet.
The quantity of stone which it is neces-

ing to the wheels, a concrete wall will
be built from the upper end of the power
house to a distance of 2800 feet up-
stream, at which point it will cun-e in
to a junction with the shore. This wall
will contain a large number of openings

September 5, 1911

POWER

361

beneath the water level to allow the water
to flow freely to the forebay and thence
to the wheels, but it will shunt all ice,
logs, etc., around through the spillway,
and thus practically eliminate all inter-
ruptions to the sers'ice.

The method of construction involves
the use of the dam itself as a base for
the tracks employed for transporting ma-
terial. Three tracks are built out from
the abutment on the Illinois side. As
these tracks can be extended only as
far as the concrete has hardened it was
necessary to use some other means for
conveying the material from this point

where the new concrete was to be de-
■ nsited in the forms. This is done by
means of the two large dam travelers,
shown in the illustrations. These are
massive steel cranes provided with three
trolley tracks extending 210 feet out over
the dam from the point where they rest
upon the hardened concrete. Each of
these runways is equipped with a trolley,
tackle and carriers operated at high
speed by two reversible engines located
at the rear end. These engines are op-
erated with compressed air and are under
the control of one man.

The travelers are mounted upon six
heavy cast-steel track wheels running
upon a specially designed 100-pound
rail track laid on I-beams firmly em-
bedded in the concrete forming the dam.
The concrete to be deposited in the forms
Is run out onto the dam by trains carry-
ing a large number of buckets, each
holding 1 ' .• cubic yards. At the rear
end of the travelers these buckets are
picked up by the trolley tackle and
rapidly conveyed to the end of the track
which overhangs the steel forms to be
filled. These buckets, which can be
dumped at any point of travel, are con-

veyed by endless lines running over
spool-drum rigs, each being operated by
a separate reversible engine. The hoist-
ing and lowering operations are accom-
plished by means of single-running block
rigs operated by a more powerful en-
gine. As the work progresses the rails
are extended on the hardened concrete
and the travelers moved forward. The
forward posts of the travelers are 65
feet high, and the entire weight of each
machine. is 175 tons, including all neces-
sary equipment.

.A large amount of cofferdam work is
necessary to unwater the river bed on
which the foundations are being built.
On the Iowa side, where the founda-
tions are being installed for the power
house and locks, it was necessary to
unwater 33 acres of river bed. The cof-
ferdams are composed of a large num-
ber of timber cribs 24 feet long and 16
feet wide. They are filled with stone
and sunk to the river bed at inter\'als of
12 feet around the entire space that is
to be unwatered. When the cribs have
been placed the space between each is
closed by lowering square timber stop-
logs, after which the entire outside sur-
face is sheathed with a layer of planks
against which earth is deposited, the
earth filling the small cracks between
the planks and iTiaking the cofferdam
water tight. A layer of riprap over the
earth prevents it from being washed
away. After the cofferdam is completed
the space inclosed is pumped out by
large centrifugal pumps which throw out
the water at the rate of 10,000 gallons
per minute. The average hight of the
water outside the cofferdam is about 10
feet.

A vast amount of cofferdam work is
necessary on the prniect. and there has

probably never been a more efficient one
built than that which surrounds the
space on which the foundations for the
power house and lock are being con-
structed.

In building the foundation for the
main dam the river bed along the line
of the dam will be unwatered in sec-
tions by cofferdams 400 feet long and
wide enough to allow blasting out the
foundation. .After completing a section
of the dam, another section of the same
length will be built ahead, pumped out,
and completed in the same manner. As
the different sections are completed the
flood-gate openings will allow the water
to flow freely through the completed por-
tion of the dam. After the entire dam
is finished these flood gates will be
closed, and the water will rise to the
full hight of the dam.

No part of the work is being done
by contract, the men being employed di-
rectly by the chief engineer. All of the
machinery used in the construction work
was designed by the engineering depart-
ment of the company under the chief
engineer's supervision.

It is estimated that the initial installa-
tion of 120,000 electrical "horsepower
will be available for distribution by July,
1913. Of this amount, 60,000 horsepower
has been contracted for by the St. Louis
Public Utilities under a 99-year con-
tract; the remaining 60,000 horsepower
is to be sold in the cities near the plant.
The head of water will vary from 31
to 39 feet at the different stages of river
flow. The maximum amount of power
that can he developed is estimated at
220,000 horsepower, and the company
will install additional generating units
as the demand for power increases in
the surrounding cities and towns.

Two New Types of Dynamometer*

It is the'author"s intention to confine
himself to describing two types of trans-
mission dynamometers constructed by
his own firm. One type, the torsion
dynamometer, is designed for measuring
the power transmitted to or from high-
speed machines, such as centrifugal
pumps, fans, turbo-compressors, steam
turbines, dynamos, etc., where the torque
is fairly constant and therefore need
not be recorded in a diagram. The other
type, the hydraulic dynamometer, is in-
tended to be used for measuring and re-
cording the energy absorbed by slow-
running machines of variable resistance,
such as machine tools, plunger pumps
and the like.

Torsion Dynamometer

Fig. I illustrates the torsion dynamom-
eter which may be used to couple the
shaft of the driving engine directly to the
driven machine. If desired, pulleys may
be fitted to the ends of the dynamometer

Bv Dr. Alfred Anisler

One dynamometer utilizes
a jiexible shaft the torque
of 'd'hieh serves as the index
to the fy<>:,ir transmitted.
The other uses an arrange-
ment oj tight and loose pul-
leys: poaer is transmitted
through pistons on the loose
pulley aeting on oil in eyl-
inders on the tight pulley.

and the power may be transmitted to one
end by means of a bell and taken off at

the other end also by a belt. The ends
of the driving and driven shafts are se-
curely coupled together by the shaft G.
This shaft has therefore to transmit the
entire power from the one machine to
the other, and consequently it is sub-
jected to torsion and is twisted. The
shaft is, of course, so designed that the
yield point is not exceeded. Thus the
shaft works as a torsion spring. Provided
the shaft be perfectly elastic, the angle
through which the opposite ends are
turned will be proportional to the twist-
ing moment; that is, proportional to the
power transmitted. If the shaft is made
of a special spring steel of very high
yield point; that is. above PO.(XX) pounds
per square inch, it can be twisted to a
considerahle degree without breakage.

The various parts attached to the shaft
(i serve partly for indicating its angle
of twist and partly to prevent it from
being twisted excessively by being over-
loaded. For reading the angle of twist,

362

POWER

September 5. 191 1

three disks M, N and O are used. The
disk M is fixed firmly to the end H of
the shaft; N and O are fixed to the end
F »f the shaft. The disk U is provided
with a radial slit P. To the disk M a
transparent rim U made of celluloid is
fixed on which divisions are cut. Op-
posite to the slit P a small window has
been cut out in the disk N and is pro-
vided with a fine slit T.

When the eye at Q looks through the
slit P the slit 7" will be seen as a streak
of light and the divisions will show black
on the scale U. The slit T serves as a
pointer for indicating the relative motion
of the two disks A' and O as compared
to the disk M. The line of vision is per-
fectly defined by the two slits P and T:
parallax is therefore impossible when
reading the scale and the observation
is therefore independent of the distance
between the scale U and the slit T.

When the apparatus is stationary it
will be clear that, if the shaft is twisted,
the angle of twist will be shown by the
movement of the pointer T over the
divisions on U. But this pointer and
divisions will also be visible when the
instrument is running; in fact, they will
be clearer and more defined than when
the instrument is at rest, for while it is
necessary to place the eye close to the
slit P when the instrument is at rest to
see the pointer and the scale, it is pos-
sible when the instrument is in motion
to read the scale at some distance from
the slit P. The greater this distance is,
the more the scale will appear to be en-
larged; this enlargement, it should be

of impressions is given to the eye in
rapid succession, namely, once during
each revolution of the disk, the eye ap-
pears to receive a continuous stationary
image of the pointer. Should the ma-
chine work at a speed below 250 revolu-
tions per minute these images are not
continuous, and the reading of the divis-
ions becomes cumbersome, although still
possible.

To obtain a permanent impression on

ii^J

Fic. I. Torsion Dynamometer

the eye, the ;cale must be subjected
to a strong light. The short period of
observation must be stiengthened by the
intensity of the light, sinre a fixed mini-
mum amount of light energy, that is,
intensity multiplied by duration, is re-
quired to affect the optic nerve. A 50-
candlepower lamp with a ground-glass
globe suffices for illuminating the scale
and should be placed as close as pos-
sible to and behind the disk M. Instead

slit P, the two separate images will co-
incide. The angle of torque thus ob-
served shows the twist strain in the shaft,
since the slit P passes the eye at regular
intervals. Should the power transmitted
and consequently the twist of the shaft
vary rapidly, the eye will see different
parts of the scale in rapid succession
and the image will become blurred, mak-
ing it impossible to read the scale ac-
curately. When high-speed machines are
used, this disturbance need not be feared,
while the inertia of the machine itself
and that of the disks M, N and O of
the dynamometer will restrain any oscil-
lations thus formed. If the twist varies
periodically in synchronism with the ro-
tation of the shaft, the wave of twist
variation being repeated, every revolu-
tion can be followed by the eye by look-
ing at the scale through the slit at dif-
ferent points around the dynamometer
shaft.

Since the shaft and the other parts
connected to its extremities have no ten-
dency to move due to the centrifugal
force, the readings of the dynamometer
are independent of the speed. The in-
strument can therefore be run at any
desired speed, provided no forces are
set up greater than can be resisted by
the material of which the disks are made.

The instrument is made generally for
speeds of about 4500 revolutions per
minute, but some instruments have al-
ready been made for 7000 and even 8500
revolutions per minute. The coefficient
of elasticity of the shaft can be deter-
mined when dt rest by fixing a lever of

Fig. 2. Hydraulic Dyna.mo.meter

noted, is independent of the speed. The
reason why the scale is still seen when
the machine is running is due to the fol-
lowing: The eye looking at the scale
through the slit P sees the pointer and
scale once for every revolution, and only
during the very short time when the
small slit P is passing before the eye;
the light impression is therefore in-
stantaneous. One of these impressions
would he too small to leave a permanent
image in the eye, but since a number

of looking at the slit P directly it will be
found better to insert a mirror so that
the scale can be observed from the side
as shown in Fig. 1. That the eye be
not dazzled, the daylight should be
screened off. The observations can best
be made in a dark room and only one
eye should be used, since each eye
would tend to form a separate image
which would blur the actual reading. If
the head is held so that the line con-
necting the two eyes is parallel to the

known length at one end and loading
this with weights.

The largest instrument at present made
can measure torques up to 130.200 inch-
pounds and the smallest up to 694 inch-
pounds. The instrument suffers from
but one defect, namely, the air resist-
ance of the rotating parts. For the time
being, it need merely be stated that the
influence of the air is very small, es-
pecially when the dynamometer is so in-
serted that the disk M is placed nearest

September 5, 1911

POWER

363

to the machine the power of which is to
be measured. It is possible, although
somewhat laborious, to make accurate
determinations of the influence of the air
resistance on these readings. The
dynamometers are so constructed that
they can without any difficulty be placed
or taken out from between the driving
and driven machines, and another shaft
can readily replace the former without
having to move either of the machines.

Hydraulic Dynamo.meters

The hydraulic dynamometer, which is
used for measuring and recording the
power absorbed by machines subjected
to a variable load, is illustrated in Fig.
2. The dynamometer is driven from the
engine by a belt and transmits the power
by a second belt to the driven machine.
The driving and driven pulleys D and B
are placed close together on a common
shaft. The pulley B is fixed to the shaft
C, while the pulley D runs loose on the
shaft without any appreciable friction.
To the pulley B the two cylinders F are
fixed, which are connected by means of
the two tubes G to the center of the hol-
low shaft C. The pulley D is provided
with two projections J which press
against the piston L. The piston works
without any friction in the cylinder F
owing to the omission of any packing,
and the fact that the entire system is
filled with oil. When the pulley rotates
in the proper direction, the projection /
presses back the piston in the cylinder
F, thus exerting a pressure on the oil.
This oil pressure is transmitted through
the hollow shaft C to a fixed tube, the
end of which fits axially into the shaft
C and is properly packed by means of
a stuffing box. The pressure is further
transmitted to the casing N, to which on
one side a pressure gage O is fixed and
to another side the recording apparatus.
The pressure gage indicates the torque
with which the pulley B drives the pul-
ley D, since the latter is proportional to
the oil pressure. The transmission of
the oil pressure to the recording ap-
paratus is quite similar to that of a
steam-engine indicator; the p^-Pcr strip is
rolled up in the hollow drum Q and
passes under the pencil of the recorder
and is then rolled up on the drum /?.
The paper strip passes under the pencil
at a velocity proportional to the speed
of the shaft C. In order that the num-
ber of revolutions of the shaft C may be
checked readily, a small hammer is at-
tached which gives an audible lap at
every tenth revolution of the shaft C.
These taps can readily be timed by
means of a watch. The area of any
portion of the diagram represents the
energy absorbed by the machine, and the
ircan hight. that is, the area divided by
the length of the diagram, the average
power transmitted.

If the resistance of the machine, the
power absorption of which is to be

measured, is very irregular, the pointer
of the pressure gage will oscillate
violently and the recorder will draw a
zigzag line. These oscillations can be
readily reduced by closing the valve U
to a greater or lesser degree; by so do-
ing the opening through which the oil
enters through the shaft C into the cas-
ing N can be increased or decreased as
desired. This dynamometer is not nearly
as simple and does not indicate the
power as directly as the torsion dyna-
mometer; it is consequently less accurate
and needs watching. On the other hand,
measurements can be made which are
impossible to obtain with the torsion
dynamometer, namely, the power is con-
tinuously recorded on a strip of paper
and can be accurately determined, how-
ever much it may vary.

The readings given with the hydraulic
dynamometer are not entirely independ-
ent of the speed; the centrifugal force
tends to drive the oil in the tubes out-
ward and to move the piston L axially.

die position. If the dynamometer is al-
lowed to run at a low speed, the disturb-
ing action of the centrifugal force in
the pistons when no complete compen-
sation is obtained becomes negligibly
small. Another reason for keeping the
speed of the instrument low is sn ac-
count of the centrifugal force causing
the pistons to rub against the sides of
the cylinder. The dynamometer illus-
trated may be used for torques up to
13.020 inch-pounds.

The same principle of construction
can be applied for measuring higher
powers; the instrument is then simply
placed in series with the transmission
shaft, and instead of the pulleys B and
D, couplings are used. It is, however,
necessary in this case that one shaft
should be hollow for its entire length
so that the hydraulic pressure can be
measured at the end.

Growth of Mariiif lurhine

The accompanying diagram, showing

King Edward "-1901

The Queen"- 1903

' Virginian"- 1905

riCT.

Atlantic Liner

according to the position in which the
pistons are relative to their respective
cylinders. By means of a suitable ar-
rangement of the pistons and cylinders
with regard to the pulley B it is pos-
sible to compensate these two forces;
this is only possible, however, for one
position of the pistons, namely, the mid-

■eo.ooo I. Hp .

the growth of the marine turbine from
its first successful use in the "Turbinia"
in 1894 to the present, is reproduced
from a reprint in F-nnincrrin^.

The paper was read before the In-
stitution of Naval Architects by the Hon.
Charles A. Parsons, of which body the
author is vice-president.

364

POWER

September 5, 1911

Drying Out a Flooded Sub-
station
By a. D. Blake

A submerged motor is not an uncom-
mon thing in power-plant practice, but
tlie spectacle of a substation entirely
under water is a very unusual one.

The substation herein discussed is lo-
cated in a sump (see Fig. 1) soine 50
feet below tide-water and handles the
drainage from a deep cut covering an
area of two square blocks; the water
is pumped up into the sewer through a
24-inch discharge pipe against a head

the minds of those in charge, and there-
fore no additional precautions were
taken. But, as is often the case, the
unexpected happened. There occurred
an unusually heavy rain one night, and

the water began to come in faster than
the pump could take it out. In spite
of all the efforts of the operating force,
by morning the water had risen to with-
in 2 feet of the ceiling, submerging not
only the permanent apparatus but the
temporary motor as well.

The conditions were rather discourag-
ing when the writer arrived the next
morning, especially as the installation
was about 90 per cent, completed and
it was now evident that several weeks
would be required to undo the damage
that it had taken the rain only a few
hours to accomplish.

The first thing to be done, of course,
was to get the water out. Fortunately,
there was an air line close at hand, so
an air pump was obtained and after
some hours the sump was emptied.
Everything was covered with mud and
slime, necessitating a washing down with
clean water. To do this, the trans-
formers had to be lifted out of their
cases and thoroughly cleaned, the cases
washed out and dried and the trans-
formers replaced.

The problem now confronted us of
the quickest and yet most effective
means of drying out, with the limited
facilities available. It was finally de-
cided to use both internal and external
heat where possible. A medium-size
cylinder stove was procured and hous-
ings and flues of sheet iron were con-

Fic. 1. Elevation of Apparatus before the Flooding

of 40 pounds pressure per square inch.
The equipment consists of three 11,000
to 550-volt oil-cooled transformers of
75 kilovolt-amperes each, two 100-horse-
power three-phase vertical induction
motors directly connected to centrifugal
pumps, a high-tension switch structure
containing duplicate sets of disconnect-
ing switches, oil switches, series trans-
formers and relays, and two float-
operated starters for the motors.

While the permanent apparatus was
being installed, the water in the sump
■ was handled temporarily by a 4-inch
centrifugal pump belted to a 20-horse-
power induction motor and the latter
was suspended from the ceiling to leave
more clear space on the floor. This
temporary pump had kept the water
down satisfactorily for a number of
weeks, during which period there had
been several rains and one thaw. This
created a certain feeling of security in

Fig. 2. Stove and Housings Installed

September 5, 191 1

POWER

365

>tructed as shown in Figs. 2 and 3. A
small blower connected to a 2-horse-
power motor supplied fresh dry air to
the system while the moist air escaped
through the hatch at the top of the sump.
Thus a positive circulation was estab-
lished, the air being forced into the
transformers through the 2-inch oil
drains at the bottom of the cases.

In addition to the use of warmed air,
imernal heating of the transformers was

five minutes, which it withstood without
any sign of breaking down.

Curiously enough, several barrels of
transformer oil were unaffected by the
flood. These barrels had been opened
and, consequently, the seals were broken,
although the plugs were screwed in
tightly.

Plan View of Drying Arrangements

accomplished electrically, the connec-
tions being as shown in the diagram,
pie. 4. The large transformers were
nected Y-fashion on the primary side
the 400-volt temporary line, with
;:,cir secondary windings short-circuited.
In series with one of these were con-
nected three of the small series trans-
formers with their secondaries also
short-circuited. A voltmeter and an am-
meter were connected in the circuit and
thermometers were inserted between the
nsformer windings. Readings were
.n every hour and a temperature of
htly under 80 degrees Centigrade
~ maintained. This required a primary
'ent of 4.2 amperes, which induced
imperes in the secondary windings,
iwing to the large magnetizing cur-
rent necessary for the motors and the
limited capacity of the 400-volt line, it
was decided to dry the motors by ex-
ternal heat only. These being of low
voltage, it was not necessary to take such
precautions as in the case of the trans-
formers. To increase the rate of drying,
a heater consisting of a few coils of
No. 12 iron wire was placed in each
motor housing.

A reel of cambric-insulated cable was
In the sump at the time of the flood.
This was unreeled and hung up in a
warm room for two weeks, after which
It was taken down and about 10 feet
cut from each end and discarded: there
being a possibility of the water having
worked into the ends. The remainder
was immersed in water, with the ends
out. for 12 hours aid then subjected
to a pressure test of 22,000 volts for

Readings were taken from time to
time with a portable testing set to de-
termine the insulation resistance of the
transformers and motors. These showed
at the start a "leakage" of 15 volts (on
a 110-volt circuit) between the primary
and secondary windings of the trans-
formers or between either winding and
the ground, and 90 volts between the

the small series transformers, which had
to be retaped, the high-tension side of
the equipment withstood 22,000 volts
for five minutes and was pronounced
safe for continuous operation at 11,000
volts.

The system has been in operation ever
since without giving the slightest trouble.

Installing Electric Motors
By Thomas H. Watson

Too often a motor is situated in an al-
most inaccessible place, with the result
that in order to give it the attention it
should have the motor must be removed.
In the case of exhaust fans, the motors
are often placed high up in a skylight,
and can be reached only by a long exten-
sion ladder, wMth no means of support
v.hile working on it, so that the attend-
ant can hardly be blamed for neglect-
ing them.

Steam traps and electric motors make
poor companions, but you sometimes find
them placed side by side. To place a
motor beside a flue or chimney taking
the hot gases from furnaces is about as
bad, but it is also done. Motors driving
bilge pumps that remove hot drainage
when placed over the hotwell soon be-
come grounded from the steam condens-
ing on them and give a lot of commutator'
trouble.

When putting in motors temporarily
some kind of foHow-up method should
be used to keep track of the work, and
notice should be given the person in
charge of the department in which the
motor is placed that just so much time
will be given for trial, after which the
work will be done permanently and
charged to that department. Too much
delay in completing this kind of work

Heating Coils in
Motor Housings

Diagram of Connections for Drying

motor windings and the ground. After
drying out for five weeks the trans-
former readings were brought up to 1700
megohms and the motors to a point al-
most as good.

It was then deemed safe to subject
the transformers and wiring to a high-
tension test. This was accordingly done
by means of a portable testing trans-
former. With the exception of three of

leads to a lot of broken-down wiring and
trouble.

Where adjustable-speed motors are in-
st.illcd care should be taken in placing
the resistances; they sometimes run very
hot and might cause a fire. The con-
troller should be so constructed that the
sliding shoes come squarely over the sta-
tionary buttons and leave no possibility
for poor contact and consequent burning.

366

POWER

September 5, 1911

Frothing of Storage Batteries

By John S. Leese

Owners of internal-combustion en-
gines fitted withi storage-battery ignition
are not always electricans, and thiey are
frequently bothered by the frothing of
the batteries while they are being re-
charged. When this takes place the bat-
tery loses its strength rapidly and its
voltage drops, whether it is being used
or not. Chronic frothing is generally
due to what is known as sulphating of
the plates, meaning the production of
little patches of lead sulphate on the
plates. The rate at which a cell can
be charged and discharged without in-
juring it depends upon the effective
areas of the plates, and upon the rate
of the chemical action by which the
electrical energy of the cell is set up.
If, then, the area of the plates is dimin-
ished by lead sulphate and the charg-
ing current is kept the same, it cannot
all be used in producing chemical ac-
tion on the plates, and the excess acts
upon the electrolyte, which it decom-
poses and causes to give off oxygen and
hydrogen, which is called frothing.

The most common cause of sulphat-
ing is excessively heavy overcharging,
which causes injurious chemical action
to take place. The best cure is to give
the sulphated battery long and frequent
charges at not more than half the usual
charging rate, with the addition to the
electrolyte of a solution of caustic soda
and water in the proportions of one part
of caustic soda to five of water. The
amount of this solution to be added to
the electrolyte is one-fifth of a drachm
to one pint of electrolyte.

Though this is undoubtedly the best
way of curing sulphated battery plates,
it is a long process, and operators must
not be dismayed if there is but little
improvement to be seen after the first
one or two recharges.

Electrocuted bv Current at
250 Volts

An employee at the Orr Worsted Mill,
Piqua, O., was instantly killed while
mopping up the floor in the vicinity of
the switchboard. His right shoulder
came in contact with the switch and he
was unable to move.

The fireman saw that the current was
going through the man's body and im-
mediately shut off the engine, stopping
the dynamo. When the current ceased,
the man toppled to the floor and ex-
pired after two or three gasps.

Current at the mills is reported by
the daily press to be generated at 250
volts. This is not a high enough voltage
to ordinarily cause death, but the man
had hold of a wire-wrapped hose, form-
ing a good ground, and more than likely
he was badly burned bv the current.

LETTERS

Kerosene for Lubricating
LJruslies

I have read occasionally in the col-
umns of Power suggestions for using
kerosene as a lubricant on the com-
mutator and brushes of dynamos, so I
tried it. The brushes were soaked in
the kerosene and, after wiping them well
with a piece of cloth, were allowed to
be dry. This gave a good deal of suc-
cess on a 110-volt dynamo carrying about
65 amperes. The same treatment was
accorded to the brushes of another
dynamo working at 450 volts and carry-
ing about 400 amperes, but in this case
it was not a success. On the contrary,
the brushes became more noisy and
sparking seemed to increase. An effort
was made to find out if there was any
other cause of the poor working, but
none could be found. To make it surer,
the brushes soaked in the kerosene and
dried were replaced by other carbon
brushes, which had not been soaked in
the oil; after a while the sparking ceased
and the chattering decreased. Both of
the dynamos were in the same room,
both were compound-wound machines
and both had carbon brushes. The
smaller dynamo is used for lighting ser-
vice and the larger one supplies cur-
rent to motors driving machinery.

Will someone tell me the cause of this
apparently paradoxical experience? Is
it probable that the higher voltage and
greater current-carrying capacity can
have anything to do with the difference
in the results, and if so, where is the
limit?

Manilal K. Desai.

Ahmedabad, India.

Grooving Commutator Mica

We have in our station a 110-horse-
power direct-current motor, belt-con-
nected to a 150-kilowatt alternating-cur-
rent generator. This motor used to give
a great deal of trouble by sparking at
the brushes, pitting the commutator and
burning it black in spots, about the width
of five or six bars, leaving about that
many clear in between the black places
all around the commutator.

Not long ago I saw an article in
Power which described the experience of
another reader with the same trouble,
which he had cured by cutting the mica
down between the bars, so I tried it. I
made two hooks about like ordinary pack-
ing hooks but bent over a little more
at the point so as to make them dig
into the mica, and tempered them very
hard. Then with the aid of a straight-
edge laid alongside the mica to guide
the hook I found it a very easy job to
cut the mica down about 1/64 inch.

This motor is started up at 7 a.m.
and runs until 11 p.m., and formerly I

often had to stop it two or three times
during this run to sandpaper the com-
mutator, but since cutting down the mica
I have had no trouble at all and the
commutator has taken on a nice choco-
late color.

1 think this practice is all right for
high-speed machines, but would not
recommend it for low-speed machines,
because the carbon dust and other foreign
matter that might find lodgment in the
grooves would not be so readily thrown
out by centrifugal force at low speeds
but might stay there and cause a partial
short-circuit between the commutator
bars.

J. R. Wa.mpler.

Staunton, Va.

Commutator Lubrication

The practice of using vaseline or com-
mutator compounds to lubricate commu-
tators, collector rings and brushes, so
generally followed, has given me more
trouble than the use of a clean cotton
cloth saturated in gasolene; holding the
cloth lightly against the collector rings
or commutator does the work. I do not
use grease of any kind. The brushes
are all of carbon on the machines that I
am running, which are alternators of
the revolving-field type, running at 3600
revolutions per minute, and the usual
direct-current exciter.

Charles Malone.

Harlowton. Mont.

Remedies for the Loosening
of Squirrel Cage Bars

It is sometimes found difficult to make
the bars of a squirrel-cage rotor stay
fast, if they are soldered to the end
rings. The solder between the bars and
the short-circuiting rings either breaks
loose, due to mechanical stresses, or is
melted out by heavy secondary currents
at starting, allowing the bars to fly out
under the influence of centrifugal force.
The breakage of solder may be prevent-
ed by bolting the bars to the end rings
and thereby relieving the solder of the
mechanical duty.

If the starting conditions are un-
usually severe, trouble from melting
solder might be prevented by replacing
the end rings with heavier ones; another
and easier expedient is to wind over the
ends of the bars heavy bands of No. 16
or 18 brass wire, according to the clear-
ance, one band at each end of the
rotor, without any insulation under it,
and solder these bands to the ends of
the rotor bars. If neither of these rem-
edies is effective, there is nothing left
but to relieve the heavy starting
conditions.

C. J. Fuetterer.

Thomas, W. Va.

September 5. 1911

P O W E R

1 Ail C^ 1 i 1,

A Suggested Solution of the

Gas Turbine Problem

By Benjamin H. Blaisdell

The chief and seemingly insurmount-
able obstacle that has prevented the
realization of success in the development
of a practical gas turbine is the inability
of constructive materials to withstand the
high temperature of the working fluid
without some means of cooling either
the products of combustion before they
enter the turbine or the parts of the tur-
bine subject to contact with the hot
gases, at the same time not materially
reducing the heat available for con-
version into useful work. The blades or
vanes of a turbine become so inter-
mingled, as it were, with the working
fluid that water jacketing, to be effective
in preventing their destruction, must ab-

in which the gases are expanded to the
pressure of the atmosphere before im-
pinging on the buckets; still the tempera-
ture of the issuing gas is too great for
the turbine parts to withstand it.

The restriction, thus far. of the gas
turbine to the constant-pressure cycle is
another hindrance to high thermal effi-
ciency for the same reasons that this
cycle in reciprocating gas-engine prac-
tice has been proved to be of less prac-

In the modern gas engine this heat
loss is considerably diminished, since
the events of compression and expan-
sion occur in the same cylinder, giving
little time for the heat of compression
to become dissipated before it can be
utilized during the working stroke.

It is the purpose of this article to
describe a method or cycle which would
seem to overcome the difficulties men-
tioned and make the gas turbine a prac-
tical success not only from a mechanical
standpoint but in its efficiency of heat
conversion.

The heat-absorbing or conducting
power of materials is not instantaneous;
they will not assume the temperature
corresponding to a surrounding medium
without an appreciable lapse of time.

If a piece of iron were held momen-
tarily in a flame of, say, 3000 degrees
and then plunged into a medium of a

Mr. Blaisdell's Proposed Combustion Chamber for a Gas Turbine

sorb the greater part of the heat of com-
bustion, the turbine thereby becomin?
a more efficient hot-water or steam-mak-
ing machine than a machine for develop-
ing mechanical power.

If, on the other hand, steam or water
or both simultaneously be injected into
the hot gases before admission to the
turbine, the ratio of water vapor to gas
would necessarily be so great, in order
to reduce the temperature to a safe de-
gree, as to practically change the work-
ing fluid to the characteristics of super-
heated steam with its comparatively low
heat range and high latent heat losses
in the exhaust aggravated by the im-
practicability of condensing.

Divergent nozzles have been employed

tical efficiency than the constant-volume
cycle employed in all modern gas en-
gines. In the constant-pressure cycle
not only much higher initial compres-
sion is required to obtain a given mean
effective pressure but the operation of
compressing the gases must be accom-
plished in a separate cylinder or ma-
chine from that in which the power is
generated, requiring the handling of
gaseous fluids in comparatively large
compressors. This cannot be done effi-
ciently by present methods on account
of the loss to the jacket water of much
of the heat generated by the compres-
sion of the gases and loss by radiation
before the heat can be converted into
power.

much lower temperature, say, steam at
300 or 400 degrees, this performance
could be repeated indefinitely without
a destructive rise in the temperature of
the iron. It is just this principle which
it is proposed to apply in the operation
of a turbine to prevent the hot gases
from raising the temperature of the in-
terior parts above the safe limit.

The products of combustion will enter
and pass through the turbine during the
period of one explosion and expansion
unmixed with any cooling fluid to lower
the thermal efficiency, then will follow
a period of steam admission at high pres-
sure and in a moist state for the pur-
pose primarily of lowering the slight heat
rise due to the previous passage of the

368

hot gases; incidentally it will augment
by its expansion the power output of
the machine. These two events will fol-
low each other continuously and no water
jacketing of the turbine will be required;
in fact, the turbine may be covered with
heat-insulating material, thereby eliminat-
ing entirely the present heat loss to the
cooling water which is unavoidable in all
gas engines.

To generate the steam for cooling it is
proposed to utilize what in present prac-
tice is waste heat. If the exhaust gases
be passed through a properly designed
boiler, steam may be generated at a pres-
sure of 200 pounds for passage through
the combustion chamber and turbine,
thereby reducing the temperature of the
exhaust to 500 degrees Fahrenheit, or
even less, provided the water vapor in
the exhaust is maintained in a super-
heated state to prevent the formation of
sulphuric acid which might endanger the
metal of the boiler.

Furthermore, the heat of compression
of the gases can be utilized by passing
the boiler-feed water through the com-
pressor jackets and coolers. The com-
bustion chamber may or may not be
water jacketed. For the best thermal
efficiency it would be better to insulate
the corhbustion chamber and depend on
the steam for preventing a serious tem-
perature rise. Any degree of cooling may
be obtained by supersaturating the steam
to a greater or less degree.

It is proposed to employ a combustion
chamber which completely fills with the
combustible mixture before ignition, and
when combustion occurs it is so rapid
as to be practically an explosion, the
maximum pressure reached depending
on the degree of compression and the
heat value of the mixture used.

The combustion chamber which I pro-
pose to use will be elongated in shape
and will be directly connected to the
inlet of the turbine. The igniter will be
located at the extreme end nearest the
turbine and the admission valves for air,
fuel and scavenging steam will be ar-
ranged in a chest at the other end of
the chamber. All the valves will open
and close automatically at the proper
instants in the cycle by the fluid pres-
sures employed and not by valve-gear
mechanism. By this automatic opera-
tion the minimum pressure at the tur-
bine inlet or nozzle will be practically
that of the fuel and air supply, and the
ignition cannot take place until the
chamber is completely full of combus-
tible mixture. The admission valves close
at the instant of explosion, and steam
is admitted alone during the period
succeeding the explosion and previous
to a fresh charge of air and fuel. It
would be impossible to perform this
cycle with equal results by valves or
ports operated or controlled by mechan-
ism driven from the turbine shaft.
The construction and operation of the

POWER

apparatus will be clearer by reference
to the accompanying longitudinal and
cross-sections of the combustion cham-
ber, where A is the admission valve for
fuel; B, the air inlet valve; E, the main
valve and F an auxiliary valve for ad-
mitting steam to the chamber from the
pipe ] which connects with the boiler
operated on waste heat. At / is a water-
inlet spray with a valve K for regulat-
ing the supply to give the steam the
supersaturation desired for cooling; C is
a "continuous" igniter which may be an
electric hot wire, hot tube or a bunsen
flame, and T is the inlet nozzle of the tur-
bine. A small pipe H equalizes the air
pressure back of the auxiliary steam
valve F with the supply pressure; G is a
spiral baffle provided to give the gas and
air a rotary motion in their passage
through the combustion chamber and
thereby insure their thorough mixture.
Small stems S are secured to the various
valves and project outward through
stuffing boxes for indicating the opening
and closing of the valves.

The operation is expected to be as
follows: Air and fuel enter the combus-
tion chamber through their respective
valves in proportions regulated to form
the most effective mixture and when
the volume admitted is just sufficient to
reach the igniter, the mixture is exploded
and the rapid rise in pressure instantly
closes the inwardly opening admission
valve, making the path through the tur-
bine the only exit for the products of
combustion.

When the pressure due to the explo-
sion is reduced by expansion to prac-
tically that of the steam supply, the main
steam valve opens, allowing the steam
in a supersaturated state to enter the
chamber, driving out the remaining burnt
gases and in its passage through the
turbine, cooling it and generating power.
The auxiliary valve is so balanced that
when the air pressure back of the pis-
ton is equal to the steam pressure be-
tween the two disks, it closes; in fact,
the steam flow assists in its closure, thus
assuring the discontinuance of steam
admission before the opening of the air
and fuel valves again. This completes
one cycle and the performance is auto-
matically repeated as long as the condi-
tions necessary for its operation con-
tinue.

The proper proportioning of the mix-
ture may he obtained by carrying the air
pressure a certain degree higher than
that of the fuel gas. This excess pres-
sure of the air would further be bene-
ficial to the operations in the combus-
tion chamber by causing the air valve to
open a trifle earlier and close a trifle
later than the gas valve, thereby admit-
ting a small quantity of air to act as a
buffer between the combustible charge
and the scavenging steam.

In order to use liquid fuel a vaporizer
or carbureter would be connected be-

September 5, 191 1

tween the air-supply main and the air-
inlet valve, dispensing with the inde-
pendent fuel valve shown in the draw-
ing.

The advantages contributing to high
efficiency which a turbine operated as
just described would have over that of
the present type of reciprocating gas
engine are manifold.

The air and gas being compressed
prior to admission to the combustion
chamber, their temperature can be re-
duced by means of water jackets, making
the fluid denser for a given volume and
pressure, thereby yielding a higher max-
imum pressure of explosion with a given
maximum temperature.

The cooler mixture would make it
possible to use a higher compression
and a greater percentage of hydrogen in
the gas without the danger of preigni-
tion.

The heat absorbed by the water in
compressor jackets can be utilized by
feeding this water to the waste-heat
boiler.

There being no rubbing surfaces in
contact with hot gases, the interior parts
of the turbine can attain safely a higher
temperature.

The maximum pressure of combus-
tion can be obtained without the neces-
sity of water jacketing, resulting in a
less rapid fall during expansion and
consequently a higher mean effective
pressure.

The scavenging steam will recover
much of the heat delivered by the hot
gases to the turbine walls and convert
it into power in the later turbine stages.

The working fluid flowing always in
the one direction through a smooth com-
bustion chamber insures a complete
scavenging of the chamber prior to ad-
mitting a fresh charge of air and fuel.

Expansion can be carried to at-
mospheric pressure, which is not prac-
tical in a reciprocating engine.

A large part of the heat now wasted
in the exhaust gases and cylinder jackets
is utilized in the machine itself.

The slightly erosive action of the
supersaturated steam will prevent the
nozzles and buckets from becoming
coated with carbon or scale.

With all these advantageous conditions
favoring the turbine unit we might ex-
pect the heat balance as compared with
that of the gas engine to be about as
stated in the following table:

Percentage of the total heat of
the fuel gas lost in the ex-
haust gases

Percentage lost in radiation
and cooling water

Percentage lost internally, in-
cluding mechanical friction
and inefficiency of compres-
sion, transmission, combus-
tion and expulsion of the
gases

Total losses

Percentage converted into
brake-power

September 5, 1911

POWER

Recollections of a Boiler
Inspector

It appears remarkable in this day of
high-class engineering papers, by means
of which even the most isolated man
has access to a higher knowledge of
engineering, that one finds so many
ignorant engineers. Following are re-
lated a few instances that have come
under my observation, which illustrate
the criminal carelessness and ignorance
of men having charge of steam boilers:

Within the past 18 months I have
found five boilers that were offered for
insurance, which had stop valves be-
tween the boiler and the safety valves.
and in only one of these cases did any-
one appear to realize that anything was
wrong. The engineer said that he knew
the stop valve should not be in such a
place, but had not had the time to make
the change. In each case, when the
seriousness of the conditions were
pointed out, a change was made without
delay. In one instance the manager.
when advised of the dangerous arrange-
ment, gave orders for an immediate shut-
down and the boilers wese not operated
again until the valve had been removed.

In another plant I found a 60-inch by
14-foot horizontal return-tubular boiler
being operated without a safety valve at
all. This boiler was located just out of
the city limits, and the negro fireman
lived with his family in the factory yard.
not more than 50 yards from the boiler
house. He would go out about 4 o'clock
a.m. and fire up. and leave the boiler
until after breakfast, but he said that
he never found more than 110 pounds
of steam showing in the gage when he
returned.

A new .S4-inch return-tubular boiler
had been set up. In shipping the boiler
from the shop the steam gage was lost
and the negro fireman went over to a
neighboring gin house, found an old
steam gage and proceeded to put it on
his boiler and then fired up. The boiler
was equipped with a ball and lever safety
valve. When the steam gage showed
60 pounds the safety valve blew. This
did not suit the fireman, as he claimed
if was necessary to have a steam pres-
sure of 80 pounds to operate the engine.
He, therefore, removed the lever and tak-
ing it to a forge had 12 inches ad-
ditional length welded to it and then
moved the weight out to the end of the
lever. He fired up and when the needle
on the steam gage registered 60 pounds

the safety valve blew again. He then
made another visit to the gin plant, got
the weight belonging to the old boiler-
safety valve and hung it on the lever in
addition to the weight already in place.
The next thing that happened was that
the boiler exploded and came to rest
about 900 feet from its starting point in
the middle of a public road. The fire-
man, his helper and one other employee
were instantly killed. The old steam
gage was found and I managed to get
hold of it, and upon testing it I found
that the needle would go to the 60-pound
mark and hang there, although I ran
the pressure up to the limit of 300
pounds on my gage. This old gage had
become rusted and foul and was abso-
lutely worthless.

W. E. NORSTER.

Shreveport. La.

• ^^^^^^^^^^^^^^^^^^^^^^

Improper I^iping
The accompanying sketch shows how
an accident happened when cutting in a
new battery of boilers. Three boilers
were in service, and as the requirements
of the plant demanded additional steam

sequence, when the two boilers were
cut in on the old steam line the con-
nection A was broken loose by the work-
ing of the pipe B, notwithstanding the
expansion joint.

Edward T. Binns.
Philadelphia. Penn.

Crude Repair Job

One of the most unworkmanlike re-
pairs on a steam engine I have ever wit-
nessed was perpetrated in one of the
largest power houses on the Pacific coast
a few months ago.

I was an operating engineer in the
plant, and the so called repairs were
made under the direction of the operating
chief engineer, who had never had a
day's practical training in his life.

In one portion of the power house
were two horizontal, tandem-compound,
surface-condensing engines, each having
cylinders of 18 and 26x16 inches. Steam
was used at a pressure of 180 pounds per
square inch. Each engine was direct
connected to two generators, each of 200
amperes capacity, the generators being on
either side of the single crank.

It is usual to run these engines 24
hours per day and seven days a week
except when the main plant is in opera-
tion, which supplies power to the ma-
chines in the manufacturing plant, there-
fore, one engine is always running. They
are changed over on alternate days. Im-
mediately the main plant is closed down,
during meal hours or at night, both en-
gines are required to he in operation to
carry the lighting load.

A Cask of Poor Piping

two new boilers were installed in an ad- Closing down the main plant at noon
joining shed as there was no room in one day. the second engine had just taken
the old plant. As the steam line was of the load, when suddenly a severe knock-
considerable length an expansion joint ing occurred in one of the engines at
was inserted. It was so arranged as to every revolution. An examination showed
move parallel with the steam main, caus- that some small pieces from a broken
ing a strain at the joint A. As a con- pisfn ring had come between the high-

370

POWER

September 5, 1911

pressure piston and the cylinder cover.
As the clearance was small the cylinder
head was cracked and the piston rod was
very much bent.

On closer inspection it was found that
the engine must have been out of line, as
a shoulder had worn on the bottom half
of the outer end of the high-pressure cyl-
inder, and a similar shoulder on the top
half at the inner end; the neck bush was
also badly worn. The same state of af-
fairs was found in the low-pressure cyl-
inder, except that the shoulders were
worn on opposite sides halfway around
at the outer and inner ends. These
shoulders were from :h to Vs inch high
at the worst places, and tapered to noth-
ing in the cylinder walls.

.=\fter an inspection of the cylinders
the operating chief gave instructions to
get pneumatic hand tools, and affixing
rough 8-inch diameter emery wheels on
their shafts, he proceeded to grind off the
shoulders on the cylinder walls, and af-
terward smoothed them down with No. 0
emery cloth. It was suggested that he
put a line through the cylinders to find
out how much they were out of line, and
then rebore them true. He stated that the
engine had been lined up a year before,
and that he would prevent further wear
on the shoulders by increasing the width
of the piston rings.

Accordingly, the recesses for the rings
were turned out, and increased 'i inch
in width in each case, new rings were fit-
ted to the pistons, new rod and neck
bushes were put in, and the engine again
assembled without lining up the cylinders.

When started up the engine pounded
badly. Numerous alterations of the valve
were made, but without silencing the
noise, and recently I heard that the en-
gine is permanently out of commission
and that the operating chief has been
superseded.

Seattle, Wash. John Creen.

Repairing a Steel Stack

Some seven or eight years ago a 46-
foot steel extension, 40 inches in diam-
eter, was added to a square-brick chim-
ney which was 72 inches high and 4
feet square, internal dimensions. The
stack was unlined and was made with
lapped joints, as shown in the illustra-
tion. Each full section was made of
two pieces of rolled sheet steel varying
in thickness from about 3^ inch at the
bottom to u. inch at the top.

Some time during the Sunday shut-
down the section A dropped down through
the steel extension, through the brick
stack and landed at the base of the
chimney, without doing further damage.
The sheet was removed through a large
door in the base of the chimney. The
local boilermaker who had made the
stack advised taking the stack dow-n and
putting up a new one, and a local con-
tractor offered to build a staging about

the stack and to replace the sheet for
about S300.

Finally, a former sailor volunteered
to carry out the work as follows: A
j;;-inch single-snatch block was put
around the three guy wires and the rope
and tackle were pulled up, on the guy
wires to the top, as shown. The more
times the rope was wrapped around the
guy wires the easier it traveled.

Before the single-snatch block and
rope were up out of easy reach, a '_■-
inch double-snatch block was hooked
over one section, as shown at B, and
traveled up the guy wires with the sin-
gle-snatch block ropes £. When the
ropes and tackle had reached the point
C the tag end of the single-snatch block
was secured. The chair D was then
hooked to the lower end of the snatch
block B. The sailor then took a pole,
hooked the snatch block F into the ring
and was hoisted in the chair to the point
C, when he hooked the reach pole over

stack was given one coat of asphaltum
paint. A small snatch block was left
at the top of the stack through which a
No. 10 weatherproof-covered wire was
passed and attached to the roof below.
With the small snatch block a reach
pole carrying a ! 2 -inch double-snatch
block might at any time be raised and
hooked over the top of the stack.

A small snatch block should always
be left at the top of steel stacks or a
ladder attached to the stack for con-
venience in painting or repairing. A
steel stack should be repainted about
every two years.

Robert E. Newco.mb.

Holyoke, Mass.

Loose Crank Pin

Some time ago I had a loose crank
pin, the actions of which I have not yet
been able to understand. The pin was
on a 16x36-inch engine, running over a-

^-. PO«vtH

Method Employed in Repairing Da.maged Stack

the top of the stack. He was then low-
ered and again mounting a chair, sim-
ilar to the first, attached to the lower
end of the snatch block F, he hoisted
himself to a hight where an examination
could be made of the sections adjacent
to the section which had dropped out.
Suitable measurements were taken and
then three 'jxl-inch bars of iron, 5 feet
long, were bolted on the section which
had dropped out. This was rolled and
straightened out and bolted in place,
leaving the bars in for extra strength.
It was found that the stack was hardly
sprung and there was no difficulty in re-
placing the original section. The acci-
dent was caused by an imperfect heading
of the rivets.

While the tackle was in place the

100 revolutions per minute and was oiled
by means of a centrifugal oiler. This pin
apparently turned in the disk and screwed
the centrifugal oiler out of the pin. I
screwed the centrifugal oiler back into
the pin and set the check nut up tight,
but in a few minutes it came out again.
This was repeated two or three times and
I was forced to put in a new pin, forcing
it in with a screw press after boring out
the hole in the disk. I fail to under-
stand why the oiler was screwed out of
the pin. If the crank pin turned in the
disk it must have been stationary in
the crank-pin brasses and this would
have caused the pin to rotate in the
disk toward the left or in a direction to
unscrew a right-hand thread. The cen-
trifugal oiler may be likened to another

September 5, 1911

POWER

crank on the other end of the pin and
if the pin unscrewed from the disk it
should screw onto the oiler at the other
end of the pin. This oiler was of the
common size with a Jj-inch right-hand
pipe thread.

Who has an explanation ?^

L. A. FiTTS.

Fitchburg. Mass.

\'ise Clamps

In the accompanying illustrations are
-nown several designs of vise clamps.
,1 A is shown a lead clamp made out of
i piece of sheet lead folded to the de-
- ired thickness, and bent, as shown by

block Z is used with the ring in the
vise jaws.

A method of holding short screws or
screw-head bolts without injury is shown
at G.

Ja.mes E. Noble.

Toronto. Can.

Engine Runs with Steam

Valves Closed
I have a 16x32-inch Atlas Corliss en-
gine which will run at slow speed when
both admission valves are closed. I have
just had the valve seats rebored, new
valves fitted and set with the aid of an
indicator, and it runs faster now with

Types of Vise Clamps

the dotted lines, to conform to the shape
of the vise jaws.

^n iron clamp, shown at B, is used
to hold iron pipes or bars in a bench
vise. The designs of both side and top
clamp are illustrated.

Wooden clamps of this description
are valuable for holding a light tube.
If the tube is lacquered it should be
protected by wrapping a piece of cloth
or felt around it before inserting it in
the wood clamp.

What might be called a spring clamp
is shown at C, and is generally used for
holding screws, tubes, etc.; the clamp
should be made of copper so that the
threads of the bolts, etc., will not be
damaged. A spring X Is attached to
the clamp, but a bench vise is neces-
sary to obtain a suitable holding grip.

The clamp shown at D is generally
made of copper, the vise jaws gripping
it at Y.

A pair of hardwood clamps are
hown at E, the face of each of which
lias a piece of felt attached, over which
a covering of soft leather is fastened
by means of screws or nails to the wood.
They are used in holding delicate metal
work requiring only moderate pressure.

A method of holding a piston ring
in a vise is shown at F. The wooden

the admission valves closed than it did
before reboring.

I know of a 20x36-inch engine of the
same type and make that does the same
trick, although it has only been run six
months. Perhaps the valves are not set

t

i

Crosshead Pins

I have long contended that the cross-
head pin of a steam engine should be
made larger than most engine builders
njake them.

The friction might be a little greater,
but wear which creates a knock and
necessitates frequent adjusting would not
be so great if there were more surface
over which to distribute the wear.

The crosshead pin would not be too
large if made the same size as the crank
pin, although I have seen crank pins on
side-crank engines that were smaller than
the crosshead pin should have been.
Lloyd V. Beets.

Nashville. Tenn.

Graduating a Safety Valve
Lever

My experience has been that but very
few lever-safety valves are correctly
graduated.

The illustration shows a 3-inch safety
valve on a framework and a platform
scale. First, I remove the cover from
the valve body and bolt the cover A to
the timbers B and C. The hight of the
valve D is so adjusted that the lever E
will be in a perfectly horizontal position.
Then the weight F is placed at the 100
notch. The diameter of the valve being
3 inches, its area would be
3 ■ 3 • 0.7854 — 7.0686 square inches.

The total steam pressure necessary to
raise the valve when the weight F is at
the 100-pound notch is
7.0686 \ 100 =^ 706.86 = 707 pounds.

If the scale balances when set at 707
pounds, the lever has been graduated
correctly. If it does not balance at this
point, shift the weight slightly to the
right or left until the scale does balance.
Mark this point on the lever and it will

.>]-l
^

J

Safety Valve on Frame Over Platform Scai i

right or the engine is defective. No mat-
ter how we set the admission valves the
engine acts the same.

I would like to hear from other en-
gineers having charge of this make of
engine.

O. Lantz.

Archbold. O.

be the correct lOO-pound notch.

In the same manner test the gradua-
tions of the other points on the lever
with the scale, being careful to mark
each point correctly. Of course, it is
necessary that the scale be in good con-
dition and properly balanced.

Salem. Va. K. L. Morris.

POWER

September 5, 1911

Available Meat to Steam
Boilers

I have read with interest the editorial
in the July 18 issue upon Mr. Morley's
treatment of the available heat to steam
boilers. Mr. Morley shows clearly that
some of the heat is absorbed by the mois-
ture in the coal and is lost, this moisture
passing into the flue as highly super-
heated steam. He suggests that the heat
necessary to evaporate and superheat this
moisture should be deducted from the
heat value of the dry coal, to obtain the
heat available to evaporate the water.
While his observations as to moisture in
coal are true, yet there appear to be a
number of objections to his proposed
change in the method of computing the
efficiency of the boiler.

Moisture in coal, like ash, is an inert,
noncombustible substance. Both the ash
and the moisture absorb heat and carry
it, the one into the ashpit, the other into
the stack. If the heat lost by the mois-
ture is to be deducted from the available
heat, then, to be consistent, the heat lost
by the discharge of hot ashes from the
furnace should likewise be deducted.

The difference indicated between the
two methods of computing boiler effi-
ciency is small. While it is true that
the moisture content of coal may vary
considerably from time to time, especially
with coal stored in the open, the differ-
ence in efficiency that may be produced
by other conditions, such as altering the
proportion of air to fuel, may greatly ex-
ceed that due to moisture.

In a series of six tests made by stu-
dents under the direction of the writer
during last spring, and extending over a
period of more than two months, the
moisture in the coal was found to vary
between 8.4 and 12 per cent. The same
kind of coal was used, and it was stored
under shelter. This does not indicate
that a very large variation in moisture is
to be anticipated when using coal from
the same source. Furthermore, a com-
plete report of a boiler trial includes a
proximate analysis of the coal, so that
in comparing boiler performances, any
marked change in the composition of the
fuel may be noted.

A certain amount of heat is inevitably
lost through the discharge of hot gases
to the stack. Even if these gases were
cooled to the temperature of the steam
before leaving the heating surfaces,
their temperature w-ould still be far above
that of the air in the fire room. It is not

Comment,

criticism, suggestions
and debate upon various,
articles.Jetters and edit-
orials which have ap-
peared in previous
issues

the fault of the boiler that this heat is
thus unavoidably lost, yet no one would
think of estimating its amount and de-
ducting it from the heat in the fuel to get
the heat available for evaporating water.
A. Scott.
Columbia, Mo.

Turbine Accident at Riverton

I was much interested in the account of
the turbine wreck at the power plant of
the Illinois Traction Company, at River-
ton, which was published in the August 8
issue.

While the cause of the accident prob-
ably never will be known, a few conjec-
tures on the probable cause may not be
amiss, as that is as near as it is possible
to get to the facts. According to the
report, the machine was supposed to be
running at about half speed, and, if such
was the case, the wreck was evidently
due to other causes than overspeed, yet
it may have been a case of overspeed
after all. If the repairs that were made
consisted of only an overhauling of the
bearings, governor, and an internal in-
spection of the steam end. no change
could possibly have been made that would
have thrown the machine enough out of
balance to wreck it. It is a fact that if
one of this type of machine is shut down
and allowed to cool off until quite cold
and then started up in a hurry, it will
vibrate very badly. I have had the pleas-
ure of overhauling a few of these ma-
chines, and have had this same vibration
occur. I always found it due to the fact
that too much load is thrown on the ma-
chine at once, and that one side of the
machine heated up faster than the other,
and put an extra side strain on the shaft.
The only thing I ever did in such a case
was to throw the load off and run the
machine empty for an hour or so, letting
it come to a uniform temperature and
then applied the load gradually and the
vibration always disappeared.

In the description of the Riverton
wreck it was stated that the governor was

overhauled. Now, it is well known among
turbine operators that an adjustment of
about 54 inch on the stem of the pilot
valve of the hydraulic governor may
cause one or more valves to stay open,
and that the machine cannot run fast
enough to cause the governor to close
them. If one were watching the valves
to see them close and saw two or three
still open, he would naturally think that
the turbine was not up to full speed. I
worked about turbines for two years be-
fore I got on to this pilot-valve stem
stunt. Only lately I had a turbine trip
the throttle twice by the emergency de-
vice. The first time I thought it was the
fault of the hook that holds the weight
up, as it had been giving some trouble,
but when I tried to hook it up again I
found that the emergency ring was too
far out, so I knew it was caused by over-
speed. I opened the throttle again, and
before I discovered which valve was
sticking, the emergency mechanism went
out again. Now, there was no indication of
the machine running over normal speed,
which was 750 revolutions, but it had
crept up to 850, or enough to trip the
emicrgency valve. This overspeeding was
caused by only one valve out of 16 re-
maining open. It is very important to
have the emergency stop always in work-
ing order, for if it came to a "showdown"
with the old type of throttle, one Could
not close it by hand soon enough to save
the machine if some of the valves hung
up. It is absolutely imperative that each
time the machine is shut down, it be done
by tripping the throttle. The safety de-
vice should be tested very frequently, and
always after working on the carbon pack-
ing, as on some machines it is necessary
to disarrange part of the safety mechan-
ism when working on the packing.

This testing is done by having some-
one hold a tachometer on the shaft while
some one else holds a valve or two open
and another stands ready to trip the
throttle if necessary. One may readily
see from the foregoing that it is possible
for a machine to attain a dangerous
speed in a short time while everything
is apparently all right.

I hardly think the burst wheel was
damaged by tools being left in the ma-
chine, for they could hardly get in as
far as the hub of the wheel or dia-
phragm; besides, the rotating of the ma-
chine would tend to throw the tools out
to the bucket edge of the machine, and
the noise set up under these conditions
vould plainly indicate that something
was wrong inside. On the other hand,

September 5. 1911

POWER

373

if something were caught up next to the
hub, the vibration necessarily set up
uld call attention to it. The broken
.dition of the hub of the diaphragm
. les not necessarily denote that anything
was caught there, for it is self-evident
that even after the wheel had broken,
due to the terrific speed at which it was
running, if such was the case, the dia-
phragm would tend to hold the wheel in
the casing until such time as the hole in
the diaphragm became large enough to
permit the pieces to fly out. Whether
the step-bearing oil pressure failed would,
1 think, have been no cause for such a
wreck, for the symptoms of a step-bear-
ing oil-pressure failure are not to be
mistaken. When the pressure fails the
"i; remaining around the step and guide
•ring takes on various colors and tem-
atures, mostly black, and smoke rolls
:ut of the vent pipes, creating a very
noticeable odor, the machine vibrates
badly, and in the course of a half minute
01 so one may hear the shroudings begin
to rub. Generally, if one gets the throt-
tle closed at this time the material dam-
age is usually confined to the step and
guide bearings, the damage to the step
tcing due to natural (or unnatural)
causes, and the guide bearings being
damaged owing to the fact that all the
cuttings from the step have to pass
through the guide bearing if there is any
oil circulating at all.

Of course, there will always remain
the theory that this wreck was caused by
a flaw in the wheel. But it does not seem
possible that the wheel would run for
a number of years and then give way
tinder half speed. I am inclined to be-
lieve the cause of the disaster was over-
speed.

K. C. Jones.
Reno, Nev.

An Engineer's Experience

I went through an experience in the
winter of 1907-8 that I do not care to
repeat. The plant in which I was em-
ployed contained about 1500 horsepower
of wafer-tube boilers. As business was
poor and orders were few and far be-
tween, it was decided to shut down for
two weeks during January. In order to
save expense the superintendent ordered
ell of the fires drawn and the boilers and
pumps drained. The pipes were drained
as far as possible, but there were some
pipes that could not be drained. I pro-
tested that fire should be kept under one
boiler at least. The temperature went
down to 10 degrees below zero, and
stayed there a week.

One afternoon I was called out at four
o'clock with the temperature at zero and
no light to work by but torches, and told
to secure some men and get the plant
ready to run the next day. "Hunkies"
were the only laborers 1 could get to
carry water to fill the boiler which, owing

to the bad weather, took nearly all night.

1 had asked permission to bring a loco-
motive crane, which was fired up, around
to the boiler room and run a temporary
line from it to a small pump and use
that to fill the boiler, but the superintend-
ent had told me to "fill her by hand."
We filled it by 2 a.m., and, after knock-
ing some of the ice off the manhole, we
got the plates in. With the water level
just up to the manholes there was just

2 inches of water showing in the glass.
Firing up under the circumstances
seemed dangerous, and I hated to try it,
but I was told that if" I did not want to
do it there were a dozen engineers in
town who would. So I started the fire
with 2 inches of water and everything
frozen solid. We had previously built a
fire under the feed pump to thaw it out,
and at about 3.30 we had 40 pounds
steam pressure with which we tried to
start the pump to fill another boiler. The
pump would not start, however, although
I tried to thaw it out with steam. All
the time the water level was getting
lower. We had to cut in 110 feet of 12-
inch header to get steam to the pump,
and this condensed a great deal of steam;
besides, the blowoff may have leaked
some.

In a short time we heard a tube pop
and then another, and by the time we had
pulled what little fire there was left the
rest were burned. The result was that
the next week a boilermaker put in 120
new tubes and five headers which, w-ith
other repairs, cost about SIOOO.

1 certainly was mad and discouraged
that morning, and my clothes were frozen
stiff. We tried the same trick with the
No. 2 boiler. While the laborers were
filling it 1 examined the pump and found
one cylinder about half full of ice. Evi-
dently the bleeder had become plugged
up with scale and the water did not all
drain out.

We got No. 2 full and a fire started
when the tube caps began to leak. The
fire was pulled in time to prevent burning
this boiler. The caps on both ends of
No. 3 were then taken off, cleaned and
replaced. While this was being done the
superintendent consented to use the loco-
motive crane to furnish steam to the
small pump and to thaw out the feed
pump. After a while we got the pump
to pull water from the pond and filled
No. 3 boiler. After we got this boiler on
the line things began to look prosperous,
and after 40 hours of steady hustling
and no sleep we got the plant started
with three boilers. The total cost of put-
ting the plant in operation, including the
damage to No. 1 boiler, was about $1200.

1 was exonorated of all blame for the
burned boiler by the owners, but that
did not help matters any.

This trouble could have been avoided
In three ways. Connecting the city water
to the main water line would have cost

about S25. The locomotive crane could
have been used in the first place, or one
boiler could have been kept fired up for
about $35. But they would not listen to
the advice of their engineer.

This is only one case of several that
1 could cite in which the engineer was
not allowed to use his best judgment.

Mr. Beets, in the August 8 issue, asks
who is to blame when plant owners are
not more informed regarding dangerous
conditions. He also asks why should an
engineer be forced to take questionable
orders from a boss, who is ignorant, etc. ?
He should not, but the boss says, "That
boiler belongs to me. and the inspector
says it is safe. If you don't want to do
as I say you can quit and someone else
will do it." When a man has a family
to care for and no money ahead, what
can he do but obey orders? The engi-
neer can help matters by showing his em-
ployer that he is an expert in his line
and not a common laborer, and by refus-
ing to work for a firm that will not recog-
nize him and pay him as such.

J. Case.

Hyattsville. ^^d.

Massachusetts License Laws
and Examiners

After relieving himself of a heavy bur-
den "touchin' on an' appertainin' to" the
Massachusetts license law and examin-
ers, J. A. Levy, in the August 1 issue,
says that he knows that his sentiments
regarding the Massachusetts license sys-
tem are held by men all over the State.

Their name is legion who are fond of
expressing those sentiments, they are
practical men only in their own esti-
mation, but when weighed in the
balance they are found wanting. The
term practical engineer is indefinite,
its meaning depending upon the char-
acter of the person using it. While
there are a few men of no edu-
cation who are able to keep a plant in
good repair and economical operation,
there are many who seem to think that
a practical engineer is one ignorant of the
philosophy and mathematics of steam en-
gineering but who has been permitted to
"bluff" a job. There is also a type whose
practical knowledge consists in knowing
how to "queer" a plant when about to be
discharged, so as to make his successor
sick of his job. One of th^-e was dis-
covered bv a man who, on beginning his
duties in a hotel, found the steam-heat-
ing and hot-water systems and electric-
elevator service out of commission since
the "practical man" had left. When the
successor closed the blowoff valve on a
hot-water heater he soon had steam and
hot water to give away.

The fault with the electric elevator was
that the commutator was varnished and
there was an open circuit in the solenoid
which resisted the brake spring. Another

374

POWER

September 5, 191 1

"practical engineer," when about to be
discharged, set the steam gage ahead and
the safety valve back 40 pounds, so the
engine would not carry the load. Still an-
other believed in doing his dirty work
before being discharged. His pump stop-
ped for want of cylinder oil and his finish
came when he wrote a note to the super-
intendent saying that the man in charge
did not know how to set a valve.

When such people denounce the license
system, their "kick" only reacts to bring
to the support of the law every man who
believes in qualifying before expecting to
get a license. Instead of complaining
that the present scope of examinations is
too severe, a more thorough examination
should be asked for. Suppose an appli-
cant goes prepared to answer 2000 ques-
tions. After he has given 100 correct
answers, the examiner takes it for grant-
ed that he can answer 1900 more, and
issues him a first-class license.

What can be said of a case where a
man goes prepared to answ-er only 50
questions and is given a first-class li-
cense after correctly answering 30? It
could be said that he was lucky.

To eliminate the element of luck, the
examiner has no recourse; but he is bet-
ter able to judge the fitness of the appli-
cant after several examinations, which
work to the advantage of the applicant in
remembering what he has learned.

If examinations are to be so slack that
a would-be engineer does not have to
remember anything, then the State might
as well require an applicant for a li-
cense to go before an examiner and give
a song-and-dance.

V. J. Ironside.

Boston, Mass.

J. A. Levy's letter in the August 1
issue under the above heading interested
me considerably. In steam engineering
today so much theory and practice go
hand in hand that the engineer who fails
to keep pace with the times must sooner
or later be relegated to a more humble
position in favor of one who has both the
necessary practical experience and theo-
retical training.

Mr. Levy cites a number of questions
which were put by the examiners to an
applicant for a second-class license who
failed to pass. Mr. Levy argues that the
questions were unfair. Personally, I do
not see anything particularly improper
in the questions quoted. I do not think
that the applicant was rejected solely
through his failure to answer the ques-
tions. It is possible that there was some-
thing else which the applicant did not
disclose for fear of incriminating himself.

Mr. Levy further states that when men
who have had charge of large power
plants for years candidly make the
humiliating statement that under the
present conditions they could not get a
third-class license, there is something

wrong. It is my belief that if those engi-
neers would take down their dust-covered
engineering books and magazines and get
busy with them that "something wrong"
would soon disappear.

There is a type of engineer who never
has time, so it is claimed, to read engi-
neering books and uptodate magazines;
but he does have plenty of time to stand
on street corners with his "hammer" and
"knock" and disparage the successful en-
gineer, who improves himself whenever
he can.

A. Lamarine.

New Bedford, Mass.

Power Plant Betterment

I read the criticism of Mr. Cox in the
July 4 issue of Mr. Hunt's paper, printed
in the issue of May 2, and agreed so
emphatically with the latter that I had to
send along a few of my opinions and ex-
periences.

While believing in the isolated plant in
a great majority of instances, and admit-
ing that there are cases where the cen-
tral-station proposition is the only feasi-
ble one, I believe that in many places
the latter has won out simply because of
the troubles pointed out by Mr. Hunt.
I am connected with a concern building
steam engines and visit a good many
plants in the course of a year. In selling
new engines, old ones are often taken
in exchange, but there is no trouble in
disposing of them. No matter how bad
they are, and a few of them defy descrip-
tion— somebody always has the money to
keep them running. These are probably
some of the dilapidated outfits to which
Mr. Hunt referred.

Mr. Cox says most engineers possess
an indicator and know how to use it to
set the valves. Personally, I doubt if one
engineer in ten in plants of 250 horse-
power or under owns an indicator. This
statement is borne out by the amount of
indicating business done by the various
engine-building concerns at $10 and up.
The men with enough ambition to pay
S50 for an indicator do not linger long in
the small plants under consideration.

Our experiences in indicating engines
for outside parties are often laughable.
The engineer will beg for a card for his
own, and when he gets it he will ask if
it is a good one. One engineer', who had
been running a small compound engine
for about a year, w^anted to know whether
the drain from the receiver to the trap
should be open or shut. "I do not want
to waste any steam," he said, and had
been running with it closed.

I know of a plant in which there are
four men, two day and two night, who
have all risen from yard laborers inside
of 18 months. One engineer I met had
never seen an indicator used without a
pantograph reducing motion. To see
some of the above men running an
economy test and making use of a CO

machine would prove highly instructive.
Of course, we meet a few real engineers
in our rounds, but they are always with
the people who pay fair wages and have
uptodate plants, into which the central-
station solicitor knows better than to ven-
ture.

I believe Mr. Hunt's idea of periodical
visits by an expert is a fine thing, for
even where the engineer is a good man
and recommends improvements, "famil-
iarity breeds contempt," and the man-
ager follows the advice of the expert
when he will not listen to his ow^n engi-
neer.

John Bailey.

Milwaukee, Wis.

License Agitation in Rhode
Island

In Power for May 16, I was much in-
terested in the account of the license agi-
tation in Rhode Island. I was not at all
surprised at the opposition from those
who imagine that their interests are
threatened by license laws, but I was sur-
prised to learn that a Boston man who
appeared before the committee said he
was opposed to the bills; that he had
come to the hearing to intercede for the
engineers and to save the public of Rhode
Island from the troubles which had been
experienced in Massachusetts. He said
that the object of the bill was to legislate
certain men out of positions in order that
others might get ;hem.

I had been operating and in charge of
two different plants long before the
license law was ever thought of in Massa-
chusetts, and there was not very much
ill it in the way of money in those days.
Then I went down to Rhode Island think-
ing to better myself, but instead I found
things a good deal worse. I was sent to
take charge of a large plant in a woolen
mill in a -small town. I reported at the
office, and. after they had given me a
whole lot of instructions as to what they
expected of me, I asked them about
money matters. They told me that they
paid the last engineer S9 per week; but
seeing that I had come well recommended
they would pay me SIO. They also said
that the fireman was in charge at that
time, and they could not see but what
he was getting along all right. I left
v.ithout even looking at their plant. That
is what one may expect in a no-license
State.

Some of us are kicking against license
laws instead of helping them along and
projecting our interests as well as that of
the public. How would some of these
kickers against license laws like to see
laborers taken out of a trench and put in
charge of steam boilers as I have seen
done in a no-license State? Let them
think it over.

John McInis.

Cambridge, Mass.

September 5, 1911

P O W E R

375

Trouble with Leaking Tubes sidering these cases of variation, it is

plain that the value for frictional horse-
In his letter in the July 18 issue, under power is practically constant for all
the above. Mr. Reimers states that three amounts of cylinder oil fed to the en-
months after the installation of a new gine." If this statement be true, engi-
boiler with but two sheets, double-riveted neers had better start to reduce the
lap seams, and with two through stays amount of cylinder oil used to the "irre-
below the tubes, the tubes began to leak, ducible minimum."

I have had charge of similarly con- Some time ago the United States Gov-
structed boilers and never found that the ernment conducted some tests on a type
stays were the cause of the tubes leaking, of vertical engine used for driving light
Ir one boiler that leaked the feed water dynamos on battleships, and obtained re-
entered at the front end with no internal suits completely at variance with those
pipe. The tubes had to be attended to of Mr. Heck. In these tests the foUow-
e\ery cleaning day. After an internal jng results were obtained:
pipe was installed there was no more

trouble from leaking tubes. In the case ^.^^ ^, ^^^^^_ o„„,,,Lubri. ^pTKilowlftT

of an internal-furnace type of return- cant camper Hour hour

trbular boiler with one stay on each side gjj 2.2 2!) 7

of the furnace and just under the tubes, Oil! !!!!!. '..'.!! o!ij 33! i

the feed water entered through the blow- Kerosene!;!!!! 3 6 31 2

off. The tubes began to leak four or five ^^^ff„\„„„„ ,n " :!: 2
months after the boiler was installed,

>"d within the year cracks appeared at The kerosene, gasolene and soda solu-
rivet holes on the back of the fur- tion were used to wash out and thorough-
ce. I suggested to the master mechan- ly remove any oil that might adhere to
iv that the feed pipe be changed to the the cylinder wall. These tests prove con-
center of the boiler as in the locomotive clusively that there is a reduction of over
-e. This was done, and not having 20 per cent, in efficiency between running
m for an interna! pipe, we made a the cylinders thoroughly lubricated and
•ig thread on the entering pipe and put entirely without any lubrication,
a tee on that so that the water in enter- One thing which may vitiate the value
in^ would not strike directly on the tubes of Mr. Heck's tests is that besides the
but fall between the shell and the tubes, possibility of the brake load varying, the
This was a great improvement, and as friction losses of the shaft bearings, ec-
the boiler was badly scaled, a new set of centric, crosshead guides, crank pins. etc..
tubes was put in: these tubes never probably were not constant throughout
leaked the following year, all during the test. The considerable effect that
■ich the boiler was used. these quantities might have on the re-
I think Mr. Reimers will find that the suits is indicated by the tests carried on
inner of injecting the feed water has some years ago by Professor Thurston,
ch to do with his trouble, especially He analyzed the results of a series of
; he has no feed-water heater. tests and segregated the various friction
WiLLiA.M Beaton. losses in an engine. He found that in
Gold Roads. Ariz. the case of a straight-line 6- by 12-inch
^;__^_^__^____^--^-— — -^-—^^^^^^ engine with a balanced valve. 32.9 per
-. ,. , , , . cent, of the entire friction loss was due to
V. ylliulcr I .unrR-atloil ^^^ piston and rods, the remainder being
Referring to the contribution of Mr. consumed in the main bearings, crank
Heck, which appeared in the July 25 is- pins, valve gear?, etc. In the case of a
sue, it is unfortunate that the results straight-line 6- by 12-inch engine with un-
obtained did not furnish reliable data balanced valve, 25 per cent, of the entire
which would have enabled engineers to friction load was due to the piston and
formulate some law as to the amount of rod, the remainder as previously noted,
cylinder oil necessary for an engine of a With a 7- by 10-inch Lansing engine with
given horsepower. locomotive valve gear, 21 per cent, of the
The proper lubrication of steam- entire friction loss was in the piston and
engine cylinders is certainly a branch of rod, and the remainder as noted,
engineering In which there is a woeful From these tests it is evident that dur-
lack of accurate information, and I would ing h\r. Heck's test the larger portion of
like to suggest that if there are any the friction load may have varied enough
engineers who are in a position to make to account for the rather erratic figures
tests similar to those carried on at Purdue he obtained, especially in view of the
University, that they endeavor to secure fact that the hearings were lubricated
data on this matter of cylinder lubrication bv sicht-fced nil cups rather than by
and send it to Poiver. .Such information flooded or force-feed beanng lubrication,
would be invaluable to the engineering It might not be out of place to mention
fraternity at large. If such tests were here that engineers are not so much
made over a longer period I believe more concerned in the amount of oil necessary
dependable results would be obtained. for bearing lubrication, for. fortunately,
T hardly believe engineers will agree all of the oil used for bearings can be
with Mr. Heck's statement that "even con- collected, filtered and used over and

over again, as is .low done in uptodate
power plants. From the standpoint of
economy with the cylinders, however, the
case is different, as whatever oil is in-
jected is lost beyond recall.

I would like to ask Mr. Heck how of-
ten the indicator diagrams were taken,
and if there was any gradual increase in
the indicated horsepower from the first
diagram taken after a large drop of oil
was fed and the last taken before the
next drop reached the cylinder. This
might throw some interesting light on the
test and would give a better idea as to
the value of a lubricant in cylinders.
Theoretically it would seem that after a
large slug of oil reached the cylinder
the friction work would surely be de-
creased, but that on account of the oil
being washed off by new steam and by
the scraping action of piston rings, the
cylinder walls would soon become "oil
dry" and the friction work would again
rise to a larger value. For instance,
take the test of a straight-line engine
turning at 272 revolutions per minute;
when the oil was only fed at the rate of
one drop every three minutes, the engine
made 816 revolutions without receiving
any lubrication.

If a continuous indicator were used or
if the ordinary indicator diagrams were
so timed that they could be referred to
the time of the injection of each drop of
oil. any variation in power noted, as
pointed out above, would give a good line
on the comparative value of hydrostatic
lubrication, and some of the more recent
types of force-feed lubricators now on
the market.

In at least one type of the latter class
of lubricators, provision is made for feed-
ing oil drop by drop at any rate desired,
but a further refinement is introduced
whereby these large drops of oil are
caught up and subdivided again and a
small amount of oil fed into the cylinder
for every stroke of the engine. Theoret-
ically this latter principle seems to be the
better, but here again actual practical in-
formation is lacking, and if this could be
supplied it might enable us to entirely re-
vise and greatly improve the present sys-
tems of cylinder lubrication.

George F. Fenno.

New York City.

E.xperinientinij with COj

I was greatly interested in T. P. Wil-
liams' letter in the July 25 issue.

^'ill Mr. Williams kindly tell us what
the uptake temperature is, whether the
draft is regulated by the damper or by the
furnace and ashpit doors, and at what
place in the boiler setting does he ob-
tain his samples? At the time 14 per
cent. CO, was obtained, was any test
made for CO?

Joseph Anderson.

Knowles, Cal.

376

POWbR

September 5, 191 1

Hccit Loss Due to Moisture in
Wood

What is the difference in heat value
between green and dry Oregon fir? In
other words, what is the loss in heat
for each percentage of moisture con-
tained in the wood?

E. H.

When ordinary soft wood, such as fir,
is green it contains anywhere from 25
to 50 per cent, of moisture. After dry-
ing in the air for about one year the
moisture will be reduced to between 18
and 25 per cent.

The heat value of bone-dry fir is about
9000 B.t.u. per pound. Each percentage
of moisture in the wood decreases the
amount of heat available to the boiler
by about 102 B.t.u. per pound.

Thus, green fir containing, say, 40
per cent, of moisture, would have an
available heat value of
9000 — (102 X 40) = 4920 B.t.u. per

pound
Whereas, fairly well seasoned fir con-
taining, say, only 20 per cent, of mois-
ture, would have an available heat value
of

9000 — (102 X 20) = 6960 B.t.u. per
pound.

P/uus;er Pump l^isc/uirire
Regulation

When feeding a boiler with a power-
driven plunger pump, how is the dis-
charge controlled?

F. G. J.

On most, if not all, power-driven
pumps there is a valve called the bypass
which controls a passage between the
suction and discharge chambers of the
pump. With this valve wide open the
water, instead of going out through the
discharge pipe, goes into the suction
chamber and is simply churned back and
forth.

By partially closing the bypass the
quantity of water going to the discharge
pipe can be regulated to any degree up
to the capacity of the pump.

Pump Dimensions for Gi-ven

De/ive?-}'

An engine develops 600 horsepower on
25 pounds of steam per horsepower per
hour; what size of ordinary duplex pump
will be required to supply the water 25
per cent, in excess of what the engine
uses?

H. D. P.

Questions are^

not answered unless

accompanied by thej

name and address of the

inquirer. This page is

ibryou when stuck-

use it

2ci ib. per horsepowe
600 h.p.

Min.inlhi.eo^l.s.OOO Ib. per hour
250 lb. per min.
28 cu.in. per Jb.

front- of the rivets, must be either the ten-
sile strength of the ligament between the
rivets or the shearing strength of the
rivets themselves. The strength of the
portion of the plate between the rivets

7,000 (

i.in. per min.

■ o.68- =

= 9943-75 pouno-s

per inch of seam length.

2) SJ50 cu.in. per min.. 25% excess
Pistonsp'd.in.
permin. 600') 4.375 cu.in. per min., each cylinder
7 16 sq.in. =area plunger

A 3-inch plunger has 7.07 square inches
area, and will be large enough in view
of tne low piston speed used. 50 feet
per minute.

Strength of Cone Seam

A tank is 48 inches in diameter
and built of ;4-inch plate which has
a tensile strength of 60,000 pounds per
square inch. At the lower end of the
tank is a cone which has a single-riveted
lap seam. The rivet holes are 11/16
inch in diameter and the pitch is 2
inches. What is the strength of the
seam?

P. L.

The longitudinal joint of a cone-
shaped section which is withstanding in-
ternal pressure is subjected to a vary-
ing stress. The stress at any point in
such a joint will be inversely propor-
tional to the distance of the point from
the axis of the cone. It is not practicable
to make a joint that would offer equiva-
lent resistance to these varying stresses;
hence, it is customary when the cone is
made of one sheet to make it of the
same strength as the tank itself. If
several sheets are used in making up the
length of the cone, the longitudinal joint
of each course might be designed for
strength inversely as its distance from
the axis. This, however, is rarely done
except in large tank work where the
size makes the saving in material an
object.

The strength of the seam is the
strength of its weakest part, which, ne-
glecting the crushing of the sheet in

|<-s-->i
Tank with Cone-shaped Bottom

Steel rivets in single shear are as-
sumed to have a shearing strength of
42,000 pounds per square inch of cross-
sectional area; the cross-sectional area
of a rivet 11 16 inch in diameter is
0.37122 square inch, and the strength of
the rivets is

0-37I

X 42,000

= 7795.62 pounds

per inch of seam length, which, being
weaker than the ligament, is the strength
of the seam.

While the seam is of equal strength
throughout its length the internal pres-
sure per square inch required to shear
the rivets will var\' directly as the diam-
eter of the cone. For instance, on a line
corresponding to a diameter of 40 inches
the bursting pressure of the cone will be

' '^ ' ^ 389.75 pounds
20

per square inch. For a diameter of 16
inches the seam will fail at

779S.62 . J.

-^ — ■ = 974-45 pounds.

September 5. 191 1

POWER

377

Issued Weekly by the

Hill Publishing Company

John A. Hill, rn». and TreM. Rob't McKbxn, Sec'y.

505 Pearl Street, New York.

122 South HlchUan Bou]ev«r«I. Chicago.

6 Bouverle Street, LoiLloii, E. C.
UDter den Linden 71— Berlin, N. W. 7.

Correspondence suitable for the col-
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must be given — not neces.sarily for pub-
lication.

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Pay no nione.v to solicitors or agents
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Subscribers in Great Britain, Europe
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to the London Office. Price 21 Shil-
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Entered as second class matter, De-
cember 20, 1910, at the post office at
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of March 3, 1S79.

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I mCVLSTlOX STATEilKXT

Of thin isnuc 31,000 co/^ics arc priiitcil.

Xone sent free regularly, ho returns from
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are live, net circulntion.

Contents i

Sf.nthern Callfoinia ICdison System

Increasing Kfficii-ncy of Itotary Pumps..

Water Power l>am at Keokuk

Two New Types of IJynamometcr

Prylns Out a Flooded Siil>statlon

Inolalling Electric Motors

Frothing of Storase Batteries

Kerosene for Lubricating Brushes

Grooving Commutator Mica

Commutator Lubrication

Remedies for the lyoosenlng of Squirrel
Cage Bars

A Suggesli-d Solution of the Gas Tur-
bine Prol)lem

Practical l^etlers:

Uecollecllons of a Itoller Inspector
Improper Piping. .. .Crude Re-
pair Job. .. .Repairing a Steel Slack

1/K>se Crank Pin Vise

Clamps. .. .Engine Runs with Steam
Valve Closed. . . .Crosshead Pins. . . .
Graduating a Safety Valve
I>.ver 301)

tMnriissinn I.etter« :

Available Heat to Sloam Boilers. . . .
Turlplne ArclrtenI at lllverlon . . . . An
Engineer's Experience. . . .Massachii-
wtl« License Ijiws and Examiners
....Power Plant lid icrmenl .... Li-
cense Agitation In Rhmb' Island....
Trouble with Leaking Tubes. , . .
Cylinder Lubrication .... Experiment-
ing with CO, 372

Editorials .177

Air Cooling and Moisture Precipitation..

Answers to K. .L Gnle's Questions on
Refrigeration

Flooded System of Refrleerntloa

Opening an Ammrinin .lolnt

The Christie Air Steam Engine

Halton's T Jiw

Novel Method of Overcoming ppak I<oad
Troubles

High Duty Engine at Providence

Turbines in the United States

Nav}-

The success of the steamships "Lusi-
tania" and "Mauretania," together with
several other transatlantic liners
equipped with turbines, appears to have
created the popular belief that turbines
are destined to supplant reciprocating
engines in marine practice. Hence, one
often hears the United States Navy De-
partment criticized for its apparent slow-
ness in universally adopting the turbine
and for equipping many of the later
battleships with reciprocating engines.

The fact is, however, that the pro-
pulsion of a warship presents an entirely
different problem from that of a mer-
chant ship. The problem in the latter
case is comparatively simple; funda-
mentally it is that of carrying a given
weight a given distance in a given time,
the speed being practically constant. A
warship, however, must be able to steam
at maximum speed at short notice, yet
under ordinary conditions it cruises at
half to three-quarters of this speed.
Therefore, economy under these condi-
tions is an important factor.

As is well known, the load curve of
a steam turbine at constant speed is
much flatter than that of a reciprocating
engine; consequently, turbines driving
electrical generators, as a rule, show
fairly good economy at light loads.

In marine practice, however, the ro-
tative speed is a direct function of the
load and the economy of a turbine de-
creases rapidly with a decrease in speed.
Hence the turbine-driven warship shows
poor economy at cruising speeds.

In the comparative trials of the scout
cruisers "Birmingham," "Salem" and
"Chester" last year, the "Birmingham."
driven by reciprocating engines, showed
the best economy for speeds up to
twenty and a half knots. Above this
speed the "Chester," equipped with Par-
sons turbines, showed the best results.
The "Salem," having Curtis turbines,
showed the least economy up to twenty-
two and a half knots, above which its
steam consumption was between that of
the "Birmingham" and the "Chester."

Of the latest ships, the "Delaware"
and the "North Dakota" have identical
hulls and the same rated power, the
former being equipped with reciprocating
engines and the latter with Curtis tur-
bines. On the official trials the "Dela-
ware" attained a maximum speed of

twenty-one and a half knots with an
expenditure of twenty-nine thousand
horsepower, whereas the "North Dakota"
required thirty-two thousand horsepower
when steaming at a maxiinum speed of
twenty-one knots. Since being in com-
mission the "Delaware" has established
a record for steam economy while it is
claimed that the performance of the
"North Dakota" has been disappointing
as to economy, this ship ordinarily con-
suming about one-third more coal than
the "Delaware." Furthermore, last spring
the "Delaware" steamed from New York
upon short notice for a run to Chile and
return, a distance of nineteen thousand
miles, and without any thorough over-
hauling of her engines she made the trip
to England to represent the United
States Navy at the coronation. Upon
the return trip the "Delaware" showed
a remarkably low steam consumption.

While the "Delaware" has been mak-
ing this good showing, the "North Da-
kota" has been lying at the Brooklyn
navy yard with one of her turbines out
of commission, the shrouding on the
blades having corroded and seized upon
the stationary parts, thus rendering the
ship practically helpless.

Manifestly it would be unfair to con-
demn the turbine upon the performance
of this one ship, but additional op-
portunity for comparison will be af-
forded by the new battleship "Utah,"
which is equipped with Parsons turbines
and is soon to he placed in commission.
Meanwhile, the Navy Department is to
be commended for going slowly.

A Savinjj^ of Forty per Cent.

In a steam-power plant the steam for the
approximately six -hundred -horsepower-
engine output was generated in four two-
hundrcd-horsepower boilers equipped
with forced draft operated by a small
engine controlled as to speed by the steam
pressure. The fuel used was a mixture
of Pocahontas and anthr.icite pea coal.

With clean boilers and proper methods,
an evaporation of approximately ten
pounds of water per pound of fuel should
have been accomplished, while as a mat-
ter of fact the ratio of steam made to
coal burned was less than six.

When the efficiency of a boiler plant
is low it indicates that cither the fuel
is not properly burned or that the heat-
ing surfaces are fouled with soot upon
one side or scale upon the other.

378

POWER

September 5, 1911

Wirh the comparatively smokeless fuel
used in this case it is not probable that
the fire side of the boilers was so badly
coated as to be the sole cause of the
poor results.

Inside, the coating of scale necessary
for such a poor showing would be so
thick that burning of the sheets or tubes
would be almost sure to happen.

It would seem that in the handling of
the fires either too much air was forced
through and around the fuel, chilling the
gases far below the fire temperature, or
that so little air was furnished that the
combustion was incomplete and less than
one-half the heat value of the fuel was
realized.

It is highly probable that the latter con-
dition obtained. As the amount of air
supplied to the furnace was controlled by
the steam pressure it is easily seen that
when the working pressure was reached
the fan engine would sla'cken its speed
and run only fast enough to keep the
steam pressure at the point desired.

All of the steam required to operate a
six-hundred-horsepower engine can be
easily generated by two boilers of two
hundred boiler horsepower each, and if
four were used for the work it follows
that they were underloaded and ineffi-
cient. It is ever more probable that this
inefficiency was due rather to poor fire
conditions than to fouled heating sur-
faces.

In either case here was an opportunity
for an engineer to make a record which
would bring profit both to himself and
to his employer.

For a six-hundred-horsepower plant,
where the evaporation is six pounds of
water per pound of fuel and can be
raised to ten by intelligent methods, the
saving will amount to forty per cent, of
the fuel. In one case the fuel cost
would be in the vicinity of fourteen thou-
sand dollars per year and in the other
eight thousand four hundred dollars.

The difference between these sums
represents the amount that might have
easily been saved in one plant. It also
would have prevented the installation of
central-station service, which in the end
proved more expensive than the opera-
tion under the inefficient conditions which
existed when the change was made.

Explosion,s in Ent^land and
America

Many things pertaining to boiler op-
eration are treated very differently in
England from what they are here. In
that country all vessels, pipes, receptacles
and valves are classed as boilers if used
to hold or convey any fluid, liquid or
gaseous, under pressure. They are di-
rectly under the supervision of the Board
of Trade, which appoints commissions
to conduct investigations, fix the re-
sponsibility and assess fines in all cases
of accident whether insurance is carried
or not.

On July 27, at Manchester, Eng., a
formal inquiry into the cause of the ex-
plosion of a steaming kettle at Salford,
last October, was made by a commission
appointed by the Board of Trade which
is an example of English practice. The
boiler, or kettle, as it was commonly
called, was used for steaming dyewood.
It was supplied with steam the pres-
sure of which was reduced to fourteen
pounds per square inch by means of a
reducing valve. On the kettle side of
this valve a pressure gage had been
fixed, but some weeks previous to the
explosion this gage was removed while
some alterations were in progress, and
was not replaced. There were, there-
fore, no means of knowing whether the
reducing valve was doing its work. It
was found by the commission that the
foreman who removed the valve was to
blame for the explosion and he was
fined one hundred dollars.

In contrast with this case may be men-
tioned any one of the cases of explosion
of tanks, boilers, pipes or valves in this
country, where usually the accommodat-
ing coroner, if possible, places the re-
sponsibility on some one of the dead, or
blandly rejects evidence tending to cen-
sure those really guilty.

It is certain that the reckless waste
of human life that exists in America
cannot go on forever; and it may be both
easier and cheaper to meet the ques-
tion of public safety in the near future
than to suffer from the recoil that will
surely come if a different attitude is not
taken.

Aeroplane Engines

Henry N. Atwood, a New England
aviator, has flown from St. Louis to New
York. He covered 1365 miles in twelve
days, making twenty stops, the actual fly-
ing time being twenty-eight hours and five
minutes. No individual flight exceeded
two hours.

And yet the papers say that his en-
gine is "practically wrecked. It will need
overhauling and requires a thorough
rest." It has had to have repairs, ap-
parently rod boxes rebabbitted, en route.
Other newspaper accounts speak of the
motor in terms that suggest overtaxation,
long sufferance and remarkable endur-
ance.

We realize that failure in the air means
more than it does upon the ground, and
that something has to be sacrificed to
lightness. Skipping which might be
tolerated by the chauffeur of an auto-
mobile would set an aviator to looking
for a good place to land. But, on the
other hand, engines in cheap automo-
biles, subject to all the strain and shock
and wet and dirt of a road test, will run
for over a thousand consecutive hours. If
twenty-eight hours' run in relays of some-
thing less than two and a half hours each
were anything like the limit for the aero-
plane engine in the present state of the

art, there would be a great future for fly.
ing machines.

Engineering Caliber

An engineer must be able to think
quickly when an accident occurs. Ma-
chinery may run for months without any-
thing going wrong, but when something
does happen the resourceful engineer is
the one who will win out.

It is under adverse circumstances that
the engineer can make good if he has it
in him. If he cannot make good, his
employer stands to lose.

In one case as soon as trouble occurs
outside help must be called in: but in
the other the resourceful engmeer and
his associates are at hand to immediate-
ly remedy the trouble.

Some engineers are born with a me-
chanical instinct which enables them to
see at a glance what is best to be done
in case of accident, and instead of re-
porting to the office that it will take sev-
eral days to make repairs, and depending
upon the office to see that they are
made, work such as will permit tem-
porar>- operation is begun at once, and
the loss due to a shutdown is usually
limited to a few hours.

If a man has been denied the gift
of intuition, he is handicapped to some
extent — it takes him longer to see what is
best to be done — but if he has even an
ordinary amount of mechanical ability,
he can make the ordinary repairs. Run-
out such caliber the engine room is no
place for him.

It has been held that an engineer will
be benefited by making plans as to what
he would do in case of accident, but the
chances are against any accident hap-
pening as the engineer had seen it in his
mind's eye, and his plans are liable to
go for naught.

.A better plan is to read such literature
as will make the mind a storehouse for
knowledge, and the information thus
gained can be brought into use when an
accident happens.

The engineer whose advice is asked by
his employer is he who has acquired a
practical education along steam-engineer-
ing lines, and his employer is quick to
recognize his ability to decide engineer-
ing questions.

Assume that an engine was overloaded
far beyond the economical operating
point, and it was advisable to install an-
other of equal or greater size. How
would you convince your employer that
it would be a saving to install a certain
type of engine in preference to another,
and why one valve gear instead of an-
other?

Steam engineering does not consist
merely of the routine duties about the
plant; it is the knowing how and why,
the ability to determine cause and effect
and to put into practice such methods of
operation as will produce economical re-
sults.

September 5. 1911

POWER

379

Air Cooling and Moisture

Precipitation

By F. E. Matthews

Before proceeding to illustrate the
method of calculating the amount of re-
frigeration required to cool a mixture of
air and water vapor it may be advisable
to define terms.

Air is a mechanical mixture of nitro-
gen and oxygen in the practically con-
stant proportion of 80 parts of the former
to 20 parts of the latter, a very small
percentage, about 3 or 4 hundredths of
1 per cent., of which is replaced by
carbon dioxide. Into this uniform me-
chanical mixture water vapor enters in
widely varying proportions. When the
air contains all the moisture that it can
hold it is said to be saturated. The
higher the temperature of the air the
more water vapor it is capable of ab-
sorbing before becoming saturated. At
a given temperature saturated air al-
ways contains a certain fixed quantity
of water vapor.

may or may not contam less moisture
after cooling than before, according to
whether the cooling is carried below the
temperature at which the air becomes
saturated. The accompanying table shows
the amount of vapor in pounds per thou-
sand cubic feet of air at different de-
grees of saturation at different tempera-
tures. At 100 degrees Fahrenheit and
100 per cent, saturation, for example,
1000 cubic feet of saturated air will con-
tain 2.82 pounds of water vapor, while
at 75 degrees Fahrenheit, the amount is
only 1.33 pounds, or less than one-half
that quantity, and at 15 degrees Fahren-
heit, it is still further reduced to about

specific heat of the vapor but the latent
heat of that part of the vapor precipi-
tated as well must be removed. General-
ly the process is carried still farther and
the precipitated moisture is chilled to the
freezing point and finally frozen, when
not only the specific heat of the liquid
but the latent heat of fusion is involved.
If the ice is cooled to a lower tempera-
ture the specific heat of the ice is also
involved.

It is required, for example, to cool
2000 cubic feet of air per minute from
80 degrees Fahrenheit to 36 degrees Fah-
renheit. In the following calculations
it is assumed that the amount of air to
be cooled is 2000 cubic feet before it is
cooled, and not, as it might be construed
to mean, 2000 cubic feet of cooled air.

For the sake of simplicity the air is
assumed to be dry.

Dry air at 80 degrees Fahrenheit
weighs 0.0731 pound per cubic foot; 2000
cubic feet would weigh, in pounds, 14(5.2;
the specific heat of air is 0.2377; B.t.u.
required to cool 2000 cubic feet 1 degree
Fahrenheit, 34.75; B.t.u. required to cool

POr.NDS OF AQl"EOl'< Y.\POR IN 1000 CI". FT. OF AIR AT DIFFERENT TEMPERATURES AND PER CENT. SATrR.\TION

At

lO'-j

1.5';

2(V,

2.5 '7

30 Cc

3.5 >~;

W"c

4.5%

50 t;

,55'-;

60'-,

65<:j

70'';

75 c;

SO"-;

So^r

90"^;

95 ""^

100%

KX)°

F

0 282

0 423

0 0.56

0 70.5

0 847

0 98.S

1 130

1 270

1 411

1 552

1 694

1 83o

1 976

2 117

2 259

2 400

2.541

2.6.82

2.823

9.5°

F

0 244

0 . 366

0 489

0 621

0 733

0 . 855

0.978

1 100

1.223

1.345

1 467

1 . 589

1.712

1 844

1 977

2.0,89

2.201

2.32a

2 446

90°

F

0 211

0 316

0 422

0 .527

0 633

0 740

0 S47

0 951

1 056

1 161

1 267

1 373

1.479

1 584

1.690

1 . 795

1.901

2.005

2 110

8.5°

F

0.IS2

0.272

0 363

0 4.54

0 54.5

1) 636

0 727

0 818

0 909

1 000

1 091

1.182

1 . 273

1.364

1 . 455

1 . 546

1.637

1.72S

1 .819

80°

I

0.1.56

0 234

0 312

0,3911

0 ton

0 516

0 624

0 702

0 7S1

0 . 859

0 937

1 015

1 . 093

1.166

I . 249

1.327

1.405

1 . 48:J

1.562

75°

V

0. 13.3

0.200

0.267

0 334

0 401

n 467

0 .534

0 601

0 66S

0 735

0 . 802

0 868

0 . 935

1.002

1 069

1 . 135

1.202

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h

0.114

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n 342

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0 4.56

0 513

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0 627

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0 741

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0 435

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0 105

0 1 2(1

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0 196

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0 226

0 241

0 251

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0 027

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0 0.5.5

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11 I'lM

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0 221

20° F.

0.017

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0 03.5

0 043

0 0.52

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0 (17(1

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11 IISS

(1 096

(1 105

0 114

0. 123

0 132

0 1 II

11 1 1''

n 1 >s

■ 1 176

0 176

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F

0.014

0 02 1

0 02S

0 035

0 042

0 (H'.l

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0 077

0 084

0 091

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0 II''

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0 140

10°

0.011

0 016

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0 027

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0 03H

(1 (111

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+ .5°

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0 1112

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II lilt"

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0 (137

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0 051

II 11.55

11 115s

11 1161

11 064

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0.00.5

0 007

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0.012

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0.021

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0.034

0.037

0.039

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0 III 1

0 (117

0.0 111

(1.052

-^10°

0 004

0 (Km

0 (K)N

0 010

0 012

0 014

0 016

0 018

0 020

0 022

0 024

0 026

0 028

0 0.36

0 032

0 03 1

0 036

0 . 038

0 040

— 1.5°

0.003

0 004

(I 006

0 007

0 009

0 010

0 012

0 013

0 01.5

0 016

0 018

0.019

0 021

0 022

0 024

0 028

0 028

0 029

0 031

It must be remembered, however, that
the temperature of the air does not fix
the amount of moisture that it contains
except in the limiting case of saturation.
In general, air is not saturated, and may
contain different amounts of water at
the same temperature as it varies in de-
gree of saturation; or it may contain dif-
ferent amounts of moisture at the same
deercc of saturation at different 'cm-
peraiures. Since the amount of wafer
that it is possible for air to hold in sus-
pension Increases with increasing tem-
perature, and decreases with decreasing
temperature, it is evident that the air

one-tenth of what it is at 75 degrees
Fahrenheit.

In the general case, air cooling in-
volves cooling not only the mechanical
mixture of oxygen and nitrogen, but a
large quantity of water vapor as well.
If the air contains sufficient moisture so
that the cooling brings it to the point of
saturation, the heat that must be ab-
stracted from the water vapor will be
only that represented hy the specific heat
of the vapor and the number of degrees
cooled through. If it is cooled below the
point of saturation, as usually happens
In cold-sloragc practice, not only the

2000 cubic feet 44 degrees Fahrenheit,
I.S29.

One ton of refrigeration is sufficient
to dispose of heat at the rate of 288.000
B.t.u. per 24 hours, or (dividing this
number by 1440, the number of minutes
in 24 hour.5) the equivalent rale per min-
ute is 200 B.t.u.

On this basis, the cooling of 2000
cubic feet of air per minute from 80
degrees Fahrenheit to 36 degrees Fah-
renheit would require the expenditure
of

1529 ;- 200 = 7.64 tons
of refrigeration.

380

POWER

September 5, 191 1

Had the requirements been for 2000
cubic feet of cooled air, the amount of
refrigeration needed would have been
8.36 tons, the difference being accounted
for by the difference of weight per cubic
foot of air at 80 degrees Fahrenheit and
36 degrees Fahrenheit, respectively.

LETTERS

Answers to E. J. Gale's Ques-
tions on Refrigeration

There have been received so many an-
swers to E. J. Gale's questions in the
August 8 issue that it would take up
too much space to publish each sep-
arately. It would also mean unnecessary
duplication. A summary of the informa-
tion they contain has been prepared and
is given below:

I. The consensus of opinion is that
the discharge from an ammonia com-
pressor should be hot. A Fahrenheit
thermometer in the discharge pipe should
register from 200 to 260 degrees and the
temperature of discharge should increase
as the ratio of the absolute discharge
pressure to the absolute suction pres-
sure increases. For a condenser pres-
sure of 185 pounds per square inch gage,
or 200 pounds absolute, and a suction
pressure of 15 pounds gage, or 30 pounds
absolute, the discharge temperature
should be about 250 degrees Fahrenheit.
2. A hot discharge such as recom-
mended in answer to No. 1 is obtained
by returning the ammonia vapor to the
compressor in a dry saturated state. This
quality of suction vapor can be recognized
at the compressor by the frost on the
suction line just covering the suction stop-
valve body. If the frost leaves the suc-
tion pipe in the engine room, the dis-
charge will increase in temperature, only
superheated ammonia vapor reaching the
compressor.

A cold discharge is obtained when the
frost is allowed to travel beyond the
suction stop-valve body so that it covers
the suction-valve housings and the com-
pressor body. Experience has shown that
this mode of operation does not give the
ma.ximum capacity per cubic foot of com-
pressor displacement or the lowest horse-
power per ton of refrigeration produced.
A hot discharge from superheated
vapor can be remedied by increasing the
opening of the ammonia expansion or
regulating the valves slightly until frost
appears on the body of the suction stop
valve.

A cold <Jischarge can be brought up
to proper temperature by slightly clos-
ing the expansion or regulating valves
until the frost leaves the compressor.
Care must be so exercised in manipulat-
ing the expansion valves that the feed
of those only is reduced which are al-
lowing too much liquid ammonia to en-
ter the low-pressure side of the plant.

When the return frost just covers the
body of the suction stop valve and the
discharge is still too cool, the suction
valves of the compressor may not be op-
erating properly, only a small quantity
of ammonia being discharged from the
compressor. In this case the plant will
show a falling off in capacity and the
trouble should be remedied at the earliest
opportunity.

3. The amount that the expansion
valve should be opened depends on the
conditions under which the cooling coils
or other refrigerating apparatus, which
they supply with liquid ammonia, are to
be operated. For maximum capacity, the
expansion valves should be opened far
enough so that every square foot of cool-
ing surface can produce the greatest pos-
sible cooling effect for the suction pres-
sure carried and the temperature desired
in the refrigerator. This condition of op-
eration is obtained when the ammonia
vapors flowing through the cooling coils
carry enough liquid ammonia with them
to the end of these coils to thoroughly
wet the cooling surfaces. No liquid, or
only slight traces of liquid, should be
carried into the suction mains, as other-
wise the compressor will frost over, caus-
ing a cold discharge and loss in capacity
and efficiency.

It is impossible to give any set of
fixed rules for regulating expansion
valves. The operating engineer must de-
termine the proper opening of each valve
under his care used in the plant by
carefully noting the action of the sys-
tem under various conditions of opera-
tion.

4. The higher the suction pressure the
less horsepower will be required to op-
erate the refrigerating machine. If then
the plant iis doing the work required at
the time and the suction pressure drops,
slow down the machine to maintain the
pressure that experience has shown to
give the best results. If the expansion
valves are opened further under the
above conditions too much liquid will be
carried back to the compressors and the
proper operation of the machine inter-
fered with.

5. The compressor jacket water can
readily be frozen by opening the expan-
sion valves so much that liquid ammonia
is carried back to the machine. It is
dangerous to operate most refrigerating
machines this way. as the presence of
liquid in the compressor may cause a
blowing out of the compressor head or
other injury to the machine.

6. In a properly designed plant more
work can be done with a little ammonia
in the system when the condenser pres-
sure is reduced as much as possible
so as to obtain the maximum refrigerat-
ing effect per pound of ammonia cir-
culated. Experience has shown that in
some plants better results are had under
these conditions when the condenser
pressure is increased. This is because

the plant is so constructed that with low
condenser pressure, liquid is trapped in
the ammonia condensers and does not
flow readily into the receiver. These
plants are poorly constructed and the
fault should be remedied.

7. If an expansion valve is open at
all and enough ammonia is in the sys-
tem, the coil on which the valve is lo-
cated must frost over to a certain ex-
tent as long as the back or suction pres-
sure is low enough so that the ammonia
boils below 32 degrees Fahrenheit. To
cover the whole coil with frost the valve
must be opened far enough so that liquid
is carried to within a short distance from
the point where the coil enters the suc-
tion line. When there is not enough am-
monia in the system, part vapor and
part liquid will enter the liquid main and
only those coils most favorably located
will get some liquid; the others will prob-
ably get none.

8. This condition of operation indi-
cates too little ammonia in the receiver
at times. The lack of ammonia in the
receiver may be due to too little am-
monia in the system, or else the liquid
is periodically trapped in the ammonia
condenser. The remedy for the former
is to charge more ammonia into the sys-
tem and for the latter to improve the
construction of the ammonia condenser.

9. There is no danger in operating a
refrigerating system with a high-suction
pressure.

10. To obtain the largest ice output
for any plant, the condenser pressure,
and the suction pressure as well, should
be carried as low as possible. The dif-
ference between the two pressures will
take care of itself; it depends on the
size and the efficiency of the apparatus
of the plant and the conditions under
which it must be operated.

The above summary was made up from
the answers of the following contributors:
William Chaddick, Chicago, III.; J. P.
Colton. Ohio City, O.; C. A. Scott, Wales.
Wis.; L. M. Johnson, Glenfield, Penn.;
William L. Keil, Philadelphia, Penn;
.Andrew Blair, jr.. Norborne. Mo.

Flooded System of Refriger-
ation

In Power of August 8, Victor Bonn
asked for an explanation of the workings
of the flooded system of refrigeration.
The term "flooded system" as applied
to refrigeration may be defined as a
method of supplying liquid anhydrous
ammonia to the receptacle in which the
evaporation of the refrigerant takes place.
Briefly, the flooded system of refrigera-
tion is one in which the ammonia is al-
lowed to pass through the freezing coils
and then through a trap, whiqh serves as
an accumulator, in which the liquid am-
monia is separated from the ammonia
gas in much the same w-ay that water
is removed from steam in a steam trap.

September 5. 1911

POWER

381

The ammonia gas then passes on from
the accumulator to the compressor, and
the liquid ammonia is returned by gravity
to the freezing coils and passes through
the coils again together with the fresh
liquid ammonia.

Before proceeding with the principle
fif operation of the flooded system it is
necessary to understand the action of the
ammonia in the coils. It is generally
understood that the heat abstraction, or
the refrigerating effect, is produced by
an evaporation of the refrigerant. When
any liquid is changed from its fluid con-
dition into a gaseous state a certain
amount of heat is necessary to make the
change. When water is evaporated in a
steam boiler to make steam a certain
amount of heat must be supplied even
after the water has reached the tempera-
ture corresponding to the pressure in the
boilei*, in order to change it from the
liquid to the gaseous state. The extra
amount of heat necessary to change the
water to steam without raising the tem-
perature of either the water or the steam
ij known as the latent heat. The same
principle that governs the change of water
to steam, also governs the change of
liquid anhydrous ammonia from the
liquid to the gaseous state. When liquid
ammonia, in a direct-expansion refrigera-
tion plant, passes through the expansion
valve the liquid changes to a gas in its
passage through the cooling coils, pro-
vided that sufficient heat can be abstracted
from the surroundings to supply the nec-
essary amount of heat to make the change.
If sufficient heat is supplied the am-
monia, which boils at a low temperature,
Is evaporated, the heat absorbed being
abstracted from the surroundings. On
the other hand, if so much liquid is sup-
plied that the heat abstracted is not suf-
ficient to evaporate it all, the liquid
which remains will be discharged from
the refrigerating system and enter the
suction line to the compressor. As the
liquid ammonia, of course, must not be
drawn into the compressor, a trap which
contains baffle plates similar to a steam
trap may be used in the suction line to
catch the liquid ammonia, the gas being
allowed to pass on to the compressor.
The liquid ammonia in the trap or ac-
cumulator may then be allowed to return
to the coils and to pass through again,
together with the fresh liquid ammonia
which is supplied to take the place of
the amount vaporized.

This, in brief, is a description of the
action of the flooded system of refrigera-
tion. To accomplish the foregoing re-
sults, the expansion coils are arranged
vertically and the liquid anhydrous am-
monia is supplied at the bottom of the
coils. Usually a number of expansion
colls are used and arc connected by
headers, the liquid ammonia being sup-
plied to the lower or inlet header. A
trap or accumulator is located in the
suction line from the top or outlet header

of the coils and is placed at a higher
level than is the outlet header. As the
gas and the entrained liquid ammonia
pass into the accumulator the gas is
separated from the liquid, the gas pass-
ing on to the compressor. The entrapped
liquid ammonia in the accumulator Is
then returned by gravity through a pipe
connection provided for this purpose to
the inlet header where it again passes
through the coils together with the fresh
supply. The. fresh supply of liquid am-
monia from the high-pressure side of
the system is not led directly into the
inlet header of the cooling coils but is
cooled by means of a cooling device while
still under the high pressure of the sys-
tem. After the liquid ammonia at this
high pressure has been cooled to the
temperature of the low-pressure side of
the system the supply enters the ac-
cumulator without evaporating and then
the supplemental supply and the en-
trained supply caught in the accumulator
flow by gravity to the inlet header and
then through the expansion coils where
partial evaporation takes place. The pipe
line from the accumulator to the inlet
header of the expansion coils, as well
as the accumulator itself, is so thorough-
ly insulated that evaporation will not
take place until the inlet header of the
expansion coils is reached.

By means of the flooded system of
refrigeration it is claimed that more work,
or a greater refrigerating effect, can be
produced with a given amount of evap-
orating surface than is possible with the
direct-expansion system of refrigeration.
This is because every square foot of the
heat-absorbing surface is efficient as it
is in touch with the liquid refrigerant.
In the direct-expansion system of refrig-
eration the amount of efficient heat-ab-
sorbing surface depends somewhat on
the engineer in charge, while with a
properly designed flooded system the
regulation of ammonia is automatic and
requires no attention. The supply of the
refrigerant for the flooded system is
controlled by one valve for each ac-
cumulator, while with the direct-expan-
sion system one expansion valve is usual-
ly supplied for each cooling coil. It is
needless to say that one valve feeding
a large quantity of liquid is much more
easily regulated than many valves hand-
ling in all the same quantity of liquid.

In regard to Mr. Bonn's question as
to whether the capacity of the plant can
be increased without increasing the coal
consumption, I would say that such
claims have been made for the flooded
system, and some plants have been al-
tered under a guarantee to produce a
greater output, other conditions remain-
ing the same.

Mr. Bonn also asks if there is any
automatic arrangement by which it is pos-
sible to maintain an almost constant back
pressure. The automatic regulation of
the flooded system is probably the ar-

rangement to which he refers, no expan-
sion valves being used and the regula-
tion of the supplemental liquid ammonia
being made by a single valve at the ac-
cumulator.

T. W. HOLLOVPAY.

Scranton, Penn.

Opening an Ammonia Joint

In the June 27 issue, I read with inter-
est D. L. Fagnan's article under the above
title. There are some points in the article
which I cannot understand. Mr. Fagnan
writes: "I rushed for the valves in the
engine room to isolate that coil and found
one valve partly open." Every modern
ammonia system has, or should have, a
main liquid valve.

To have performed the pumping-out
process properly, the assistant should
have closed all liquid valves in the engine
room, as there was probably no main
liquid valve, and closed the main return
valve, or at least the return valve on the
coil on which he was working. I have
alwavs found it good practice to close
all valves on the liquid line, and
all return valves unless I was sure
that the valves on the coil which
was being repaired were tight. The
low-pressure gage must be watched while
pumping back. It is a good plan to pump
down until the gage reads zero or a lit-
tle below, rap the gage occasionally and
see that the hand of the gage works free.
Stop the machine when the hand arrives
at zero or a little below, and in a short
time the hand on the gage will raise.
The system cannot be pumped down at
the first trial, and it may be taken for
granted that it is not empty until the
gage will remain at zero. Always break
the joint near the valve in the engine
room gently, and do not remove the nuts
or bolts. After this, break the joint on
the coil in which the tee is to be placed.
One may meet with some oil mixed with
a little ammonia while prying the flanges
apart; let the oil drain out before pro-
ceeding. If the gage is right a little va-
por that may have been in the line will
escape through the broken joint into the
engine room, and if the valve on the
liquid line leaks, the fumes will also es-
cape there. Had the engineer watched
his gage and not broken the joint so long
as the low-pressure gage indicated pres-
sure, he would have had little trouble.
A main liquid valve in Mr. Fagnan's sys-
tem is needed badly.

William L. Keil.

Philadelphia. Penn.

The development of cheap power on
farms where water power is available,
says the Geological Survey of Tennessee
in its magazine. The Resources of Ten-
nessee, will help to solve the problem
of "keeping the boy on the farm" and
provide a means of running it eco-
nomically and profitably.

POWER

September 5. 191 1

The Christie Air Steam Engine

Boldly claiming to be able to produce
100 per cent, more power with the same
boiler and the same fuel consumption,
the Christie Engine Company, of Water-
loo, la., has been formed for the pur-
pose of exploiting the Christie four-
stroke cycle air-steam engine. It is the
invention of E. J. Christie, of the above
town, and an actual machine rated at
300 horsepower has been constructed by
the Vilter Manufacturing Company, of
Milwaukee, Wis. *

The engine, as shown in Figs. 1 and
2, is of the Vilter company's ordinary
Corliss type with the exception that it
has inwardly opening valves in the cyl-

A T,oo-liorse power ta)iilc»i
engine, "working on the
four -stroke cycle, has been
built for some months. Ac-
tual test figures are awaited
to confirm the exorbitant
claims made by the inventor.

stroke the steam valve is opened, and as
the piston moves away the steam en-
ters, mingling with the air. As the clear-
ance is already filled with air at the
steam pressure, no steam enters before
the piston moves and it is expected that
the surfaces will be so heated by the

haust stroke at the expense of the heat
in the cylinder walls, and hence less re-
heating to be done.

The leading thought of the inventor
is, however, based upon Dalton's laws,
which are to the effect that

1. The tension and consequently the
quantity of vapor which saturates a given
space are the same for the same tem-
perature, whether this space contains a
gas or a vacuum.

2. The tension of the mixture of a
gas and a vapor is equal to the sum of
the tensions which each would possess
if it occupied the same space alone.

It is suggested that the reader who is
not acquainted with this law should read
the simple exposition of it on page 383.

From this it follows that the tempera-

FiG. 1. Longitudinal Section through Engine

inder heads to admit air and an arrange-
ment by which the main valves are pre-
vented from opening at every alternate
stroke. This is timed to occur on each of
the four cylinder ends successively.

Each cylinder end works on a four-
stroke cycle. With the steam-admission
and the exhaust valve closed, the piston
moves forward, drawing in a charge of

high temperature of the air due to com-
pression that cylinder condensation wil!
be largely avoided.

It is true that there will be a less
active interchange of heat between the
hot, dry air and the cylinder walls than
with steam; but to just that extent there
will be less effective reheating, and it is
questionable economy to take expensive-

ture of the steam in the mixture is de-
termined not by the total pressure but
by the' pressure which the steam would
exert if it occupied the same space alone.
Upon this is based the claim that in the
Christie engine the steam is highly super-
heated at cutoff. Also the steam can be
expanded down to a pressure below that
of the atmosphere without employing a

2. Christie Air-steam Corliss Engine Rated at 300 Horsepower

air which is compressed upon the return
stroke, the clearance being so propor-
tioned that the pressure attained by com-
pression is that of the entering steam.
At the commencement of the next

ly produced energy out of the flywheel
and reconvert it to heat to warm up cyl-
inder metal. If, on the other hand, initial
condensation is avoided, there will be less
water to be evaporated during the ex-

condenser, this being one of the principal
claims of the Inventor.

In the prospectus an example is cited
to show that if free air at 100 degrees
Fahrenheit he compressed In the engine

September 5, 191 1

P O \X' E R

383

up to 165.3 pounds absolute and a tem-
perature of 366 degrees Fahrenheit, and
if steam entering the cylinder at the lat-
ter pressure and temperature be cut off
at such a point as to secure a terminal
steam pressure in the mixture of 4.09
pounds absolute and a temperature of
154 degrees Fahrenheit, the air pressure
in the exhaust will be 16.12 pounds ab-
solute and that of the mixture will be
20.21 pounds.

'Taking these conditions and treating
the problem from a thermodynamic view-
point, at the beginning of compression
the air is saturated with vapor. Calcula-
tions show that of the total pressure of
165.3 pounds at the end of compression,
154.8 pounds is due to the air and 10.5
pounds to the vapor which is superheated
about 170 degrees.

Conforming »o the conditions as stated —
that is. a terminal air pressure of 16.12
pounds absolute and a temperature of
154 degrees Fahrenheit — the ratio of ex-
pansion of the air would have to be 1283.

The engine has two 14-inch cylinders
and a 36-inch stroke. Therefore, the
piston displacement in each cylinder is
3.21 cubic feet per stroke. Since the ratio
of expansion is 12.83, the volume of the
clearance must be

feet,
be at

Hence, the cuto?f would have to

• = 0.2814 c"''"" /i'''

12.82 — 1

Hence the total volume of each cylinder
is

3.21 + 0.2714 = 3.4814 cubic feet

At the terminal steam pressure of 4.09
pounds the density of the steam is 0.01 131
pound per cubic foot. Therefore, the
theoretical steam consumption per stroke
per cylinder would be

3.4814 / 0.01131 = 0.03938 pound
and at 150 revolutions per minute, the
steam consumption per hour for the two
cylinders would be

0.03938 X 150 y 60 X 2 = 709 pounds
per hour

The inventor claims that the engine is
able to develop 300 horsepower when
running at 150 revolutions per minute.
If this were so, it would mean a steam
consumption of

i"

= 2.^6 pfiundi

per horsepower-hour, the absurdity of
which is at once apparent.

Again, referring to Fig. 3, if the cycle
operates as claimed, the expansion of
the air from steam admission to cutoff
would be isothermal as represented by
A H and from H to /{ the expansion
would be adiabatic. Since the volume of
the air at the end of adiabatic expansion
is 3.4814 cubic feet and the temperature
is 154 degrees, at the beginning of ex-
pansion with a temperature of .366 de-
grees the volume would be 1.686 cubic

1.686 - 0.2714

=: 45 per crtil.

of the stroke and the air pressure deter-
mined from the formula

would be 45.06 pounds. At the begin-
ing of the isothermal expansion the air
conditions are as follows:

Temperature — 366 degrees Fahrenheit.

Pressure = 154.8 pounds absolute.

Volume = 0.02714 cubic foot.

At the end of this expansion and to
suit the adiabatic expansion, which starts
at cutoff, the air conditions should be:

Temperature = 366 degrees Fahrenheit.

Pressure = 45.05 pounds absolute.

Volume = 1.686 cubic feet.

For isothermal expansion of air

Hence the expression

154.8 X 0.2714 = 42.04
should equal

45.05 X 1-686 — 76
Since there is such a wide difference in

the steam below atmosphere; in fact, it
is a question whether the air does not
introduce more losses than it prevents.
The engine has now been built for
some months, affording ample opportunity
for testing its merits and substantiating
the claims of its inventor. Test figures
giving the water rate of the engine have
been requested on several occasions, but
these have never been forthcoming, al-
though the inventor continues to sell
stock. Data on the steam consumption
will do more than a volume of theory
to establish the claims for the engine
or condemn it. The actual test figures
will be awaited with interest.

Dalton's Laus

Suppose the vessel in the accompany-
ing sketch to have a capacity of three cubic
feet and to be divided as in Fig. 1 into
a chamber containing one cubic foot of
steam at 150 pounds, absolute, pressure.
Now suppose the partition to disappear.
The steam would expand to three times
its volume, and, since no work is done,
its temperature would remain constant.
Under these conditions its pressure

Kt^

17

^Tofal Pressure of Cutoff =l65.}lb.
^'\^Cuh>fF- Steam = l?0.i lb.

1^' ;

^

<s :

1 \

V \°-. =,oi-

^ \ \

1 i-

5

1 Vv

O-

■&K ^?j.-

' ^%^^\

§^

,f%^

^-

'/

J

^^=~;il,^ ^-^r^-,.^

-^c

—^

Voljme '^~--

. 1

V

.

^-

cO.?irofal
16.12 Air

14.7 Atmosphere

•5.?/

- 3.4814 ■

Fic. 3. .\iR-STEAM Pressure Diagram

these values, it follows that the engine
cannot operate as claimed without de-
stroying the fundamental principle upon
which the engine is supposed to operate.

Up to the point of cutoff the total
pressure is supposed to remain constant
at 165.3 pounds absolute, which is the
sum of the air and steain pressures; as
the air pressure drops the steam pres-
sure rises. Therefore, at admission the
effective steam pressure would be neg-
ligible, but this would increase as along
the curve E I- to a pressure of

165.3 — 45 1- 120.3 pounds
at cutoff. It then expands to 4.05 pounds
absolute. It is evident therefore that,
although the boiler pressure is 16,'S.3
pounds absolute, the mean effective pres-
sure of the steam will be very small.

Of course, the air cannot be looked
upon as performing any useful work; it
is merely a medium filling the clearance
spaces, being supposed to lessen con-
densation and permit an expansion of

would vary inversely as its volume and
would be

I io . ,

— ^ 50 pounds

The pressure is due to the bombard-
ment of the containing surfaces by the
molecules of the steam. The tempera-
lure of the steam depends upon the veloc-
ity of its molecules. If the velocity (that
is. temperature) is kept constant and
the volume trebled, the molecules, which
were . traveling lengthwise of the cylin-
der, will have three times as far to go
between impacts, and at the same velocity
can hit only one-third as often. Those
which have a crosswise direction have
three times as much area to cover. The
number of impacts per unit of surface
therefore becomes one-third for the in-
creased volume, with a proportionate re-
duction of pressure.

Now imagine a similar cylinder. Fig. 2,
where the smaller cottipartment is vac-
uous and the larger full of air com-

384

POWER

September 5, 191 1

pressed to 150 pounds absolute. If the
partition were to disappear the two cubic
feet of air would expand to three cubic
feet, the temperature would remain con-
stant and the air would be at a pressure
of

lOo pounds

150 X 2
3

Again imagine the cylinder, as in Fig.
3, to have steam on one side of the parti-
tion and air on the other, both at the same
temperature and pressure. If now the
partition should disappear, what would
happen? The steam would not stay in
one end of the cylinder and the air in
the other, but the molecules of each
would be diffused throughout the whole
vessel.

The pressure due to the steam would
fall just as it did when the air was not
there, for the injpact of its molecules

lute pressure of 4 inches of mercury)
and the temperature of the condensate
is 110 degrees, the condenser must be
full of vapor of 110 degrees tempera-
ture, which the steam table tells us cor-
responds to a pressure of 2.589 inches of
mercury. There must then be air enough
present to exert a pressure of

4 — 2.589 = 1.411 inches

Novel Method of Overcom-
ing Peak Load Troubles

Users of electric power are sometimes
compelled to buy on a "peak-load" basis;
that is, not exceeding a fixed current
consumption at any time during the year
but paying constantly for that fixed maxi-
mum regardless of how much current is
used. On this basis it is evident that

■ Steam

■ 1501b

■ leu. ft:

Absolute '-,
Vacuum ':
2cu.it. ■■.

■:

\

Absolute
Vacuum
leu. -ft.

Fig. 1. Fig.

would be divided over all the cylinder
wall as before. The pressure of the air
would fall in the same way. But the
walls are subjected to the bombardment
of both the steam and the air molecules
so that the pressure upon them is the
sum of the air and the steam pressures;
and since that of the air is 100 and that
of the steam 50 the actual pressure is

100 + 50 pounds per square inch
as before.

With the above in mind it is easy to
understand the laws of Dalton, which
may he expressed as follows:

First Law: The pressure and conse-
quently the quantity of vapor which satu-
rates a given space are the same for the
same temperature whether this space al-
so contains a gas or is vacuous.

This simply means that if a pound of
steam molecules is put into a certain
space and given the velocity correspond-
ing to a certain temperature it will
exert a certain pressure. If there are
other molecules flying about in the same
space they will exert their pressure too.
If an attempt is made to put more steam
into the same space without changing its
temperature, the pressure will go up, be-
cause there will be more molecules to
impact per second at the same velocity.

Second Law: The pressure of a mix-
ture of a gas and a vapor is equal to the
sum of the pressures which each would
possess if it occupied the same space
alone.

If in a condenser, for instance, there
is a vacuum of 26 inches (say an abso-

Sfeam
1501b.
Icu.-ft.

,;/,.;VJJ//.:V/777T.

150 lb.
Zcu.fr.

■l//,/)l>//U^yj/J/^J^^JlJJ,7777V~:

2 Fig. 3

continually running close to the speci-
fied limit or vice versa, keeping the cur-
rent consumption low at the time of
greatest load is advantageous. The former
procedure is impossible in many manu-
facturing processes, as it is in lighting

stance, the low cost and satisfactory op-
eration of a 400-horsepower steam-tur-
bine unit are utilized in effecting the econ-
omy. In the Lachine plant, a 14-inch,
two-stage, double-suction turbine pump
with a capacity of 6,000,000 gallons per
24-hour day is utilized to provide water
supply and fire protection for the city,
the water pressure being ordinarily 80
pounds per square inch and for fire 120
pounds per square inch. The lower pres-
sure is obtained by closing one valve and
operating only one stage of the pump.
The speed remains the same for both
services.

Current is purchased by the year on a
basis which is all right for lighting the
city and for pumping at all times of the
year except the three winter months dur-
ing which the lighting load is greatest.
It was figured that operating the pump
by steam for four or five hours a day
during that period could be made less
expensive than buying sufficient electric
current to operate entirely by electricity.
As further advantages of an auxiliary
steam installation, the insurance rate on
the pumping station could be reduced
and the city could be better lighted dur-
ing fall evenings without incurring un-
reasonable additional expense.

It was therefore decided to arrange the
pump for operation by a 400-horsepower
induction motor the greater part of the
time but by a steam turbine during the
peaks in the lighting load in winter and
in case of accident in the electric line.

The installation, furnished by the John
McDougall Caledonian Iron Works, Mon-
treal, is shown in the accompanying

MOTOR-TURBiNF.-PUMP INSTALL.MION AT LaCHINE, CaN.

and street-railway work; the latter is
usually attempted by the use of storage
batteries.

Those who have studied this peak-load
problem will be interested in a novel so-
ultion which has been quite successful
in the municipal lighting and waterworks
plant of Lachine, Canada. In this in-

photograph. The pump, of Worthington
make, runs at 1200 revolutions per min-
ute and is direct connected to an AUis-
Chalmers-BuIIock motor on one side and
a 400-horsepower four-stage Kerr turbine
on the other. Either driving unit can
be thrown into or out of use instantly
bv means of clutches on the shaft.

September 5. 1911

POWER

385

High Duty Engine at
Providence

About a year ago the old Nagle en-
gine at the Hope station of the Provi-
dence water works was replaced by a
Worthington high-duty, triple-expansion
pumping engine of 10,000,000 gallons
capacity.

The new engine has two high-pressure
steam cylinders, each 16 inches in diam-
eter, two intermediate cylinders 25 inches
in diameter and two low-pressure steam
cylinders of 46 inches diameter. The
two double-acting water cylinders are
each 24 inches in diameter and the com-
mon stroke is 24 inches. The engine is
of the self-contained type with three
steam cylinders for each side arranged

Fic. 1. Hope Statp . : I'k ...i.Ncn
Water Works

tandem, each set of steam cylinders be-
ing directly connected to one double-act-
ing water plunger. Each of the steam
cylinders has two admission valves on
top and two exhaust valves on the bot-
tom, all of a modified Corliss type. The
former are provided with a nonrelease
cutoff gear operated by a secondary four-
arm crank which is fulcrumed on the
wristplate of the main valve gear but
receives its motion from its own side
of the engine, while the wristplate of
the main valve gear is moved from the
crosshead of the opposite side in the
ordinary manner of the duplex-valve
gear.

The hieh-duty attachment is of stand-
ard design, each side of the engine hav-
ing two oscillating cylinders containing
plungers attached to the main crosshead.
These cylinders arc under constant pres-
sure from the discharge main and this
is increased to the required amount by
an interposed diffcrcnfial accumulator.
The effect of the plungers is to resist
the advance of the piston rod at the be-
ginning of the stroke and assist it at the
end. By thus alternately absorbing and
exerting energy, due to the different
angles at which the force is applied in

relation to the motion of the water plung-
ers, these compensating cylinders per-
form the function of a flywheel, and,
what is most important, the power they
exert increases in almost exact propor-
tion to the decrease in the power of the
expanding steam.

To eliminate the possibility of the en-
gine short-stroking under a variable load,
a stroke-adjusting device of recent de-
velopment is attached which automatical-
ly maintains a practically constant stroke.
This device is so arranged as to change
the back pressure of the accumulator
whereby the compensating cylinder load
is correspondingly increased or decreased
as may be required for the lengthening
or shortening of the stroke of the en-
gine.

The pump ends are of the sectional
plunger and ring type with the suction
and discharge chambers solidly bolted
to the pump barrels. The latter are pro-
vided with horizontal valve decks con-
taining multiple water valves of small
diameter but of sufficient area to insure
quiet operation. The condenser is of
the surface type through which passes
all of the water pumped by the engine.

The air pump is independent and of
the crank and flywheel type. It is lo-
cated in the basement of the station
and receives steam from the main stand-
ripe and exhausts into an auxiliary feed-

iter heater located in the boiler room
irough which the feed water, after be-

Vacuum. inches ol

mercun.- 27.45 27.67 27.75

BarometfV, inches

of mercury ... . 29. 9J 30.02 130.00

Disciiarge p res-
sure, pounds

g:»ge 73.14 79.94 73.64

Suction pressure,

pouiuls sage. . . 5.13 5.70 6.37

Total pressure

pumped against,

pounds 67.64 73.70 66.72

.\verage stroke of

engme, inches. . 24.75 24.68 24.77

Revolutions per

minute 39.38 27.22 2.t 74

Piston speed, feet

per minute 162.4 112 106.3

Million gallons of

water ijumped. . 2.713 0.935 i.l83

Capacity, rate per

24 tiours. mil-
lion gallons ... . 10.85 7.48 7.10
Total steam used,

pounds 25,422 9.832 11,475

Moisture in steam,

percent 1.71 2.3S 2.38

Total liTY steam

used, pounds. . . 24,987 9,598 11,202

Duty per 1000

pounds steam

used, million

foot-pounds... 138.6 135 132 6

Duty per 100 0

pounds dry

steam, million

foot-pounds 141 138.3 135.8

\\'ater horsepower 296 . 7 223 . 5 192

Dry stearaper

water horse-
power-hour ,

pounds 14.04 14.31 14.59

Additional credit for the heat returned
to the boilers as provided for in the con-
tract, is not included in the foregoing
figures. With this allowance, however,
the engine is credited with a duty of
149.5 million foot-pounds per 1000
pounds of dry steam when operating
under full load and with a duty of 142
million foot-pounds per 1000 pounds of
dry steam when delivering 7,000,000 gal-

FiG. 2. WoRTHiNGTON Triple-expansion IO.OOO.Ooo-callon Pumping Engine

ing passed through the main exhaust
heater, is fed to the boilers by an in-
dependent feed pump.

The results obtained at the ofRcial
trials of this engine are given in the
accompanying table, taken from the city
engineer's report.

Tfst No 1 2 3

Duration, hoiim 6 3 4
.^team pTPn*iirp.

imimiU gate. . IS1 4 ISI 2 l.M 9

Ions for 24 hours, exceeding the guar-
antee 10. ,S and 18 per cent, respectively.
To demonstrate how the engine would
operate under the various conditions met
with in actual service, additional trials
were made by pumping into the open
service with the suction taken from the
Hope rescn'oir and again with the suc-
tion taken from the street mains, also by
pumping into the closed service.

POWER

September 5, 1911

Portable Oil Burning Outfit

The accompanying illustration shows
a Hauck portable oil-burning outfit,
adapted for all kinds of repair work,
brazing and preheating in connection
with electric or oxyacetylene welding, as
well as tempering, annealing, melting,
metals and similar operations wherever
heat is required.

The outfit consists of a seamless tank,
equipped with a hand air pump, two
sets of Hauck burners and hose at-
tached to the tank and two adjustable
stands to hold the burners in a proper
position.

The burners use kerosene oil as a fuel
and give very powerful, clean flames.

sists of an endless round rubber ring
forced into a triangular space in a
corner of the flange of the removable
cylinder. This permits of replacing lin-
ers without delay, and forms a tight
joint. The pump pistons are made un-

^

JiV

Portable Oil-burning Outfit

usually heavy, wMth specially deep pack-
ing spaces. The piston rods are divided
so that when necessary to renew the
pump rod which works in the water cyl-
inder, the steam rod, which is not subject
to the excessive wear, need not be in-
terfered with or discarded.

The water-valve seats are screwed in
place and fitted with a special design
of valve bolt having a screw-driver slot
so as to do away with the use of
wrenches. The valves in the pump cyl-
inder are of a special vulcanized rub-
ber composition, made extra thick and
reinforced with a metal casing. The
rubber is of proper firmness to prevent
particles of sand and rock getting in
between the valve and seat and keeping
the valve from seating properly by im-
bedding themselves permanently into the
face of the valve.

The pump has been so designed as
to permit quickly removing and replac-
ing the parts that are likely to wear.
Pumps for this class of work are sub-
ject to excessive wear.

Another desirable feature is the ar-
rangement of the stuffing-box glands on
the water ends. The severe service will
occasionally cause breakage of the
glands, due to the extreme difficulty in
packing against this slush, and when
one breaks it would ordinarily mean dis-
mantling the pump to remove the old
gland and slip a new one over the rod.
To overcome this, the glands on the
pump end are made in halves, strongly
bolted together so that a broken gland
can be quickly and easily replaced. The

which are always under the control of
the operator. This outfit is manufactured
by the Hauck Manufacturing Company,
Richards street and Hamilton avenue,
Brooklyn, N. Y.

Blake-Know les Slush Pump

The Blake & Knowles Steam Pump
Works, East Cambridge, Mass., have de-
signed a pump especially adapted for
oil- and gas-Veil work in pumping
"slush" water. It is shown in the ac-
companying illustration.

This pump is said to be fully 100 per
cent, heavier than the pumps heretofore
used for this kiiid of service. The pump
cylinders are fitted with heavy and very
hard cast-iron removable liners, to re-
sist the scouring action of the slush
coming from the well. The liners are
flanged and are held in place with studs
and nuts. The jointing material con-

Bi.akk-Knowles Slush Pu.mp

September 5. 1911

POWER

387

stuffing boxes on the pump end of the
piston rod are made twice as deep as
those ordinarily used with such pumps
to facilitate packing the rods without
screwing up the glands excessively
hard.

In the fittings that come with the pump
special jacks are provided for remov-
ing the pump pistons from the piston
rods without having to withdraw the
rod from the pump. Such a jack is
also provided for removing the pump-
cylinder liners, which can be quickly
taken out and replaced without removing
the piston rod.

The working parts of the valve gear
and stuffingbox glands are fitted with
large lubricating oil wells into which
can be placed wicking for carrying the
oil. This permits proper lubrication
and at the same time does not require
frequent attention.

Heelv Boiler Tube Spreader
Tool

In the accompanying illustration is
shown an improved tool used for spread-
ing the tubes of Babcock & Wilcox boil-
ers. The original tool was described in
the February 21 issue of Po\x er.

The improved tool is provided with a
wide face on the adjustable spreader
head, which prevents any possible in-
jury to the tubes. With the tubes spread
as shown it is a simple matter to re-
move an old baffle wall and replace it

Heely Boiler-tube Spreader Tool

with new baffle brick without injury to
either tubes or bricks. In this design of
tool the extension end has been elimi-
nated.

No improvement has been made in
the second tool of the set. which is used
for replacine the hafflc brick in posi-
tion and consists of a gripping member,

adjustable from the end by a threaded
rod.

These tools are manufactured by the
Heely Tube Spreader Company. 346
Broadway, New York City.

Type "A" Double E.xpan.sion
Joint

The Central Station Steam Company,
of Detroit, Mich., has recently placed
on the market a new and improved type
of diaphragm expansion joint. The ac-
companying interior view of a double
joint shows the construction and method
of operation.

The double joint consists of two an-
nular diaphragms of l.eavy cold-rolled
and annealed copper, clamped at their
outer edges between a cast-iron inner
ring and two cast-iron outer rings and,
having their iimer edges spun through
and around the inner edges of the cast

Fic. 1. Interior Vie\x' of Double-expan-
sion Joint

iron backing rings. The copper is brought
up far enough on the outside face of
the backing ring to permit clamping
it securely between the backing ring and
the slip end, which is a short, flanged,
cast-iron nipple. The outer ring, inside
of and concentric with which the backing
ring is located, is recessed to a dept'i
considerably in excess of the thickness
of the backing ring.

In operation the joint is placed in the
pipe line with the slip ends, and the back-
ing rings dravn out to their farthest
I'mit. The inner and outer rings arc
rigidly anchored by cast-iron lugs into
the concrete or brick box built around
the joint; service pipes to the building':
nn each side of the street are connected
to the service outlets. As the pipe ex-
pands the slip ends ana backing rings
move toward the middle of the joint and
the copper diaphragm, which touches
the backing ring only ai the inner edge
when the pipe is contracted. Is now
drawn close over the backing ring which
reinforces it and carries the pressure of
the steam.

Fig. I shows an interior view of the
expansion joint. Very few parts enter

into the construction of this device, a
doublj joint capable of taking up the ex-
pansion in 100 feet of pipe line having
only nine parts exclusive of bolts and
anchors, and the maximum bending of
the copper at any point, due to change
of position, cannot exceed 10 degrees.'
A large factor of safety has been

Fic. 2. E.xTERioR View of Double-expan-
sion Joint
provided in the length of traverse, the
joints being designed to permit 1 '4
inches in 50 feet.

The backing ring, wiiich forms the re-
inforcement for the copper diaphragm,
is one solid heavy iron casting, present-
ing a smooth unbroken surface to the
copper.

The single joint is similar in construe
tion to the double joint except that it
has but one diaphragm and is designed
to take up the expa-'sion in only 50 fee*
of line.

New Test for Mineral Oils

Alexander E. Outerbridge, Jr., at the
recent meeting of the American Society
for Testing Materials, gave a description
of a method which he has discovered for
detecting the presence of mineral and
resin oils when mixed with linseed and
other animal and vegetable oils. He
found that the greenish bloom or
fluorescence of mineral oil and the blue
bloom of resin oil can be enormously
intensified or magnified perhaps a thou-
sand times, so that samples which have
been debloomed and show no fluorescence
in sunlight or electric light give a very
visible indication.

Light from an inclosed arc lamp is
used for viewing the specimens, and, al-
though the author does not describe his
apparatus, the inference is that the effect
is produced by the action of the ultra-
violet rays. Samples containing a very
small percentage of mineral or resin oil
are said to show the bloom or fluorescence
very markedly when viewed with this
light against a Mack background, and
by comparison with a set of samples with
a known percentage of the oil a quan-
titative determination can be made with
fair prrri<.l(in.

388

POWER

September 5, 1911

Reilly Friction Clutch

The illustration siiows a sectional view
of a Reilly clutch which is made in cut-
off-coupling style. The standard clutch
is made solid or split and can be put on
the shaft without taking it down.

This clutch is perfectly smooth on the
outside, thereby e)iminating any chance
of accidents. On the laiger sizes, a
large space inside for oil has been pro-
vided which allov/3 the ciutch to run in
oil, thereby increasing the life of the
clutch. The clutch body runs on a hard-
ened and ground bushing which pro-
tects the shaft from wear and makes an
excellent bearing for tlie clutch body.
On the larger size the shaft body is pro-
tected from wear by an additional bush-
ing.

Referring to the figure the sliding
wedge A enters the segmental cone B
which forces the thrust collar and driv-

Section of Reilly Friction Clutch

ing members C, therefore increasing the
length between the adjusting head D
and the bottom of the clutch body, trans-
ferring the thrust on the loose member
through the collar E which in turn trans-
fers the drive onto the driving member
F. This gives four driving surfaces which
act almost like a multiple-disk clutch.
It is manufactured by A. S. Baldwin &
Co., Sharon, Penn.

Cochrane Double Feed
Heater

A special boiler feed-water heater for
heating two separate water supplies is
illustrated herewith. The heater is man-
ufactured by the Harrison Safety Boiler
Works, Seventeenth and Clearfield streets,
Philadelphia, Penn. The heater is, in
general, of the Cochrane open type, re-
ceiving the exhaust steam through an at-
tached oil separator. The water supplies,
however, are received in two separate
distributing boxes which deliver to sep-
arate heating trays, from which the
water drops into separate storage cham-
bers. The idea is that in many plants
there are two different water supplies
which are used for two different pur-
poses, as where the returns or con-
densate from surface condensers is used
for washing or dyeing, while city or well
water is used in the boilers.

This arrangement represents a con-
siderable saving on cost of heaters, and

of valves, piping, etc., while taking up
much less room than one or more heaters
would occupy. The arrangement is to

txhausf Outlet
Cold Water lnletfy<^2t'' Cold Water Met

'///, Waste

Sectional View oi a Cochrane Double-
feed Heater

be used with the several modifications
of the Cochrane heater.

Vulcan Soot Cleaner as Applied
to Economizers and Man-
ning Boilers

The application of the Vulcan tube
cleaner to economizers and Manning
boilers is illustrated in Figs. 1 and 2.

The accumulation of soot and fine
particles of coke in the soot chamber of
economizers between the lower headers
where the tube scrapers do not reach
causes extra labor and loss of heat. This
objectionable feature is overcome by the
application of the steam tube cleaner,
illustrated in Fig. 1, which shows a sec-
tional elevation and cross-sectional view.
When steam is turned on the accumulated
soot is blown toward the right, as indi-
cated by the direction in which the noz-
zles incline.

Fig. 2 shows the blower as applied to
a Manning boiler. It is attached at the
top and is operated from the floor below
(the smoke-bonnet lids remaining closed),
without interfering in the least with the
firing of the boiler.

The blower arm F is fitted with a
series of nozzles which throw concen-
trated blasts of dry steam into each tube.
This blower arm is turned by means of

beveled gears and it revolves on a pivot
bearing placed at the center of the top
tube sheet and blows the tubes in rows
on radial lines.

When about to operate, first the drain
valve A is opened to blow the condensa-
tion from the steam line; the wheel B,
which opens the main valve to admit the

Fig. 2. Cleaner Applied to Manning
Boiler

steam through the nozzles, is then opened
and the third wheel D is slowly turned by
pulling the chain C gently about 4 inches
at a time, so as to allow the steam to
blow a few moments through each radial
row of tubes. This device is manufac-
tured by the Vulcan Soot Cleaner Com-
pany, Du Bois, Penn.

1

greno o' n ri r,i " "laa""' '" § '

Fig. 1. Cleaner Applied to an Economizer

September 5. 1911

POWER

389

Stilz Fuel Oil Burner

The Stilz burner is shown in section in
the accompanying illustration.

The nozzle comprises a central fitting
A through which the oil under pressure
is forced. A spiral B located within A,
near its deliver)' orifice, causes the oil
to acquire a high rate of rotation upon
passing through the orifice, so that the
actual direction of motion of the oil upon
leaving the orifice spreads it out as over
the surface of a cone.

Surrounding A is an outer casing C
having a delivery orifice larger than the
oil-delivery orifice but sufficiently re-
stricted to permit the steam, which is
used as an auxiliar>' atomizing means,
to catch hold of the film of oil and swing
it into a much larger angle of diverg-
ence and at the same time disintegrate
it into a high degree of atomization. As
all the high velocities are rotative, the
oil is spread over a large sectional area
and moves forward into the furnace at a
rate about equal to that at which the

Hinge Edge Conveyer Belt

A conveyer belt generally gives out at
the point where it bends between the
horizontal and side pulleys, at which
point side crimp will occur, caused by
the angular bending and intensified by
the sag between the carriers under heavy
load. This action is illustrated in Fig. 1.-

Fic. 1. Where Belt Crimps on Rollers

The prime requisite for any conveyer
belt formed of plies vulcanized or fric-
tioncd together is the strength, vitality
and longevity of the friction bond which
binds and holds the plies together. The

pounded to conform to the character of
the work to be done.

Hinge Edge belts are made in three
grades of cover. Grade "A," to conform
to the requirerhents of heavy ore and
gold-dredge work; Grade "B," for the
ordinary class of mining, milling, cyanid-
ing and concentration work, and Grade
"C," for handling coal, sand, gravel and
similar work.

This belt conveyer is manufactured by
John J. Ridgway, 207 Fulton street, New
lork City.

Wild's Calorimeter

This device, designed for estimating
the heating value of solid fuel, has re-
cently been put on the market by the
Precision Instrument Company, Detroit.

It is of the sodium-peroxide type in
which a mixture of the fuel and sodium

^

Stilz Fuel-oil Burner

air would be drawn into a suitably con-
structed furnace, thus affording a uni-
form mixture for combustion.

The nozzle is located in front of a
hole arranged in a wall of firebrick. All
the air entering the furnace must pass
through this hole, likewise all the
atomized oil. Both are moving at about
the same rectilinear velocity and the mix-
ture completely fills the hole in the fire-
brick, as it enters the furnace.

As soon as the brick wall of the fur-
nace becomes well heated at its inner
side, the supply of steam to the nozzle
may be discontinued, provided the pres-
sure behind the oil is sufficiently great
to spread the oil spray so as to just
clear this hot ring of firebrick. In this
case the oil spray and the current of
air, coming together while in contact with
this igniting surface, continues the com-
bustion. The supply of air is regulated
by suitable air louvers on the furnace
front plates.

This burner is manufactured by H. B.
Stilz, Valleic Cal.

Hinge Edge belt represents in operation
practically three flat belts.

The tensile strength in conveyer belts
is so much in excess of the actual re-
quirement as to make this question of
tensile strength a negligible quantity.
The necessity for rigidity in the center
and sides and for maintaining maximum
flexibility at the bending or troughing
points makes different weights of duck

Cross-section of Wild's Calorimeter

peroxide is fired in a combustion cham-
ber that is immersed in water.

The apparatus shown in the illustra-
tion consists of a combustion chamber A
suspended from the cover R by a con-
duit C which is furnished with a valve
D; £ is a copper water vessel and F is
an outside vessel, heavily nickeled, form-

Fig. 2. Construction of Hinge Edge Conveyer Belt

practically a necessity in order to obtain
the best results. This method of con-
struction is illustrated in Fig. 2. which
shows that at the bending points of the
belt but three plies of canvas are in-
serted in the rubber which surrounds
them. At the center and outer edges
there are seven plies of canvas.

To withstand the necessary wear and
tear of abrasive material a protective
cover or pad is used, and this is com-

ing an air jacket which effectually pre-
vents radiation and absorption, thus
rendering the rise in temperature of the
water a guide to the heat given off by
the fuel. A Fahrenheit thermometer is
shown at G, the scale being divided into
tenths and easily read in twentieths; H
is an agitating paddle or stirrer.

Each instrument is simple and gives
direct readings of calorific value and
evaporative power of any kind of coal.

390

POWER

September 5. 1911

A manufacturer with
a new product came into
the office a few days ago
and wanted information
regarding advertising.

We gave it to him and
showed him how our papers reach and
are read by the men in responsible
charge of plants in their various lines,
how advertising in the Hill papers
would be a good investment for him,
provided his product had merit.

We explained to him our policy of in-
serting advertisements from reliable
concerns only, and stated that inas-
much as he was not known to us, we
would be obliged to have references in
regard to his reliability and also know
whether his product had merit. We
told him that this was no reflection on
him or his product, but we had to do
this in order to protect our readers.

He gladly gave us the references re-
quired, and we are investigating these
now. If his product has the merit that
he claims, hisannouncement will appear
in our columns — otherwise it will not.
And he has plenty of money to pay the
advertising bills, too.

This manufacturer stated," I have run
up against something different here.
Heretofore my life has been made al-
most a burden by advertising men so-
liciting my business. They do not
seem to care whether my product ap-
peals to their particular class of people

or not. I am simply an-
other victim — they want
my business, that's all.

"As for investigating
the truth of my claims,
you are the first one to
bring up the subject.

"You strike a new note — you say you
will let me advertise provided I furnish
references as to the worth of my pro-
duct. Moreover, you do not talk space,
but service. You offer to render a ser-
vice— get up a definite, specific plan of
presenting my product to my possible
customers and give them information.

"Yours are the papers in which I
shall advertise, because any paper that
takes the trouble to protect its readers
as you do, must have their full confi-
dence and these are the kind of papers
that I want to have my advertising in."

Of course we are anxious to get new
advertising, but we are not so anxious
to get it as to overlook the fact that
only reliable and truthful advertising
pays in the long run.

Any other kind of advertising in our
papers will not only hurt the advertiser,
but will hurt us in greater proportion.

To be in our columns is a badge of
responsibility, to buy from here is a
guarantee of satisfaction.

This is why it pays Power readers
to read the Selling Section every week.
Are you doing it?

:i7,

Vol. 34

NEW YORK, SEPTEMBER 12, VU

No. U

IX tlie Xew York daily press McGill's cartoons
of the trials of the "Economic Husband" in his
efforts to practise economy afiford much amuse-
ment. There is a field just as fertile for the humor-
ist to be found in the "economies" sometimes pro-
posed when it is decided to install the heating sys-
tem for the new plant.

A certain superintendent of motive power and
the chief engineer of a large system were discussing
the merits of hot-water versus vacuum heating for a
large shop plant with the salesmen.

"If there were zero weather all of the time," said
the hot-water man, " there would be but little differ-
ence in the economy of the respective systems.
With the average weather conditions, about 30 degrees,
I could show better economy with hot water."

When the chief engineer asked the vacuum-heating
salesman what he could show for his system in mod-
erate weather, he replied :

" We have never made any observations for average
■weather; we only consider the coldest iveather."

It is intended in the hot-water heating article
in this issue to emphasize the
point that although extreme
weather conditions should be
given consideration, the average
weather, which occurs the greater
portirm of the year, is the time
when a possible saving in opera-
tion can be effected.

In the majority of cases, the
only condition taken into account
when the design of a plant is
under consideration is the amount
of steam necessarv' for heating in
extreme weather, and the exhaust
steam Utr this prurpose is regarded
entirely as a byproduct.

This article shows that the ])ower should be the
byproduct, as the steam for heating is fixed by
the requirements whether the engines are operated
or not, and 90 per cent, of the heat of steam at any
pressure is required to vaporize the water.

Aside from the steam employed for manufacturing
processes, in most ever\' instance, if the steam for
heating imder zero-weather conditions were used to
best advantage in an engine, considerably more
power for the plant would be available.

Where steam is used for heating the impression is
general that it makes little difference whether 5 or
10 horsepower are obtained when passing it through
the engine.

In 99 cases out of 100, all of the machines are
connected to a general exhaust pipe, with one end
to the heating system and the other with a relief
valve to the atmosphere. In moderate weather
back pressure is created on all units up to the limit
at which the relief valve is set. If part of the units
were exhausted to the atmosphere and only those
used upon the heating system
determined by the requirements
r>f the weather, back pressure on
the whole system would be re-
lieved in many cases.

The article was wTittcn by a
])ractical man thoroughly familiar
with the subject; although intro-
ducing the com|)aratively new
subject of hot-water heating by
forced circulation, a brief study
of the curves and tables will
make plain many of the compli-
cations arising in the use of ex-
haust steam in heating plants
in general.

POWER

September 12, 1911

Developments in Prime Movers

Although it is interesting and proHt-
able to study the development of prime
movers and auxiliaries of European
make, one cannot predict that similarly-
designed machines would meet with
equal success in America on account of
the different economic conditions and al-
so because of the dissimilar manufactur-
ing methods.

Boilers and Furnaces

Outside of Great Britain, the water-
tube boiler seems to hav'c been uni-
versally adopted in Europe. Attention
is now. being paid to the boiler settings,
and the marine type of boiler with its
closed sheet-steel casing is rapidly gain-
ing favor. Fig. 1 shows a boiler of this
type having 4780 square feet of heat-
ing surface with 1580 square feet of
superheating surface and 3082 square
feet of economizer surface. A chief
engineer in one of the leading English
power stations informed the writer that
they figured on 5 per cent, increase in
the economy of boilers when steel cas-
ings are used, due to the elimination of
air leakage. The boiler shown in the
illustration is installed in one of the
leading central stations of Berlin, and
under test gave efficiencies over 80 per
cent., including the economizers. With-
out the economizers the efficiency ranged
from 75 to 79 per cent, at various loads.

Attention is called to the steam drum
above the boiler proper. This is quite
common practice with German boilers.
In Germany the practice of welding cer-
tain parts of the boiler has become es-
tablished; for instance, the Borsig Com-
pany welds the water legs of its boilers
to the main drums instead of riveting
them, as is the practice in the United
States. The sheets of the Borsig boilers
are butted along the axial seams and
are riveted with butt straps. The sheets
themselves are welded together for
about 1 foot from each end, so that there
is no thinning out of the plate for the
lap where more than one end of the
sheet comes together. With this type of
boiler the path of the gases before reach-
ing the heating surface is very long,
and with the firebrick arch provided al-
most smokeless combustion is obtained
under all conditions of load. .Another
decided advantage of this setting is that
it is possible to have doors all around
the furnace thereby giving access to
any part for the purpose of breaking up
clinkers. These doors are provided with
smoked-glass peepholes so that the fire-
men can note at all times the condi-
tion of the fire without opening the door.

In Germany an auxiliary grate at the
rear of the main chain grate is used
(see Fig. 1). When the load is sudden-
ly increased, requiring heavier feeding

By Prof. A. G. Christie

European practice in boil-
ers , steam piping and aux-
iliaries as viewed by an
American engineer and
compared with o%ir present
practice. A future instal-
ment will deal with turbines
and generators.

of coal at the front of the stoker, the
speed of the stoker is increased. Under
these conditions frequently large quan-
tities of unburned coal are carried over
into the ashpits from the rear end of the
grates. With the auxiliary grate, how-
ever, this coal is held until it is com-
pletely burned and is then dropped into
the ashpit. Two pits are also provided
with most of these furnaces, one for the

j'./ yy.^.^yAv^^.jy.j'c^/^.y ^;

y^^,.v/v,^vy/XS''^' A^w^'^'-Xv V>;.vV/'<N>-/' ■'^••■/"i,<'

Fig. 1. .Marine-type Boiler with Sheet-steel Casing

small screenings of coal which fall
through the grates and the other for the
ashes and refuse. Most of the stokers
have been so developed that they
handle the low-grade coals quite as
readily as those of higher grades.

In Europe, as in many parts of the
western States, there occur large de-
posits of coal which contain consider-
able ash and slate. This would furnish
a very cheap supply of fuel in many
cases provided it could be burned with-
out trouble. Usually, however, the ash

This can only be overcome in part by
extremely fine grinding, which would
make the cost prohibitive. Fourth, there
is difficulty in handling the molten ash
which, due to the high temperature,
usually forms a solid slag.

These obstacles have been overcome
apparently by the Bettington boiler, de-
signed to handle the low grades of South
African coal and now being built by the
Frazer & Chalmers Company, of Lon-
don. This is shown in Fig. 2. Air is
drawn by means of a far through an

contents are such that they form heavy
clinkers and so destroy the furnace that
their use is prohibitive in ordinary op-
erations. While many attempts have
been made so far to burn this class of
coal, but without much success, the
utility of powdered coal in the rotary
kilns of cement mills has encouraged
inventors to adopt the same methods in
burning coal high in, ash. The diffi-
culties met with in burning coal in such
a manner may be summarized as fol-
lows: First, the difficulty of maintain-
ing continuous and steady ignition.
This is overcome only by maintaining a
uniform and very high temperature in
the furnace. Second, the failure to
find an economical material to stand the
destructive temperature necessary in
the furnace. Third, the difficulty of
maintaining a homogeneous mixture of
the fuel dust and air for the full period
required for combustion. The larger
particles naturally fall more quickly to
the bottom of the furnace; hence are in
contact with the air for a shorter period
of time and are not completely burned.

September 12. 1911

POWER

393

air heater placed—in the path of the
waste gases from the furnace and is
there heated to a temperature ranging
from 200 to 300 degrees Fahrenheit.

ber, and is connected with the lower
ring header by the concentric rings of
tubes. The inner set of tubes is lined
with special C-shaped firebrick set up
without fireclay. The steam is led from
the dome through flexible connections to
a superheater located at the base of

to the continually changing contact of
each- particle with a fresh supply of
oxygen. On account of this continuous
mixing of fuel and air during combus-
tion very little more air than that theo-
retically necessary for complete com-
bustion need be supplied. Hence very
high temperatures occur at the middle
of the furnace and the ash portion of
the fuel is converted into a liquid spray
which is projected against the firebrick
walls of the boiler. These walls fuse

Inlet iji^:' ':::■■> : .

':-if!?m0!WW^.

Fig. 2. Bettincton Boiler

This fan is of peculiar construction, and
serves both as a blower and a pulverizer,
being fitted with manganese-steel blades
which cruslj the coal. The air tempera-
ture is sufficient to evaporate most of
the moisture in the coal and the fine
coal dust mixed with air forms an ex-
plosive mixture. This passes to a dust
chamber where the heavier particles sep-
arate out and are returned to the pul-
verizer. The finer dust particles are
carried along with the air through the
tuyere pipe to the burner. The mixture
takes fire at this point, resembling close-
ly the flame from the burners of a rotary
kiln in a cement mill. The column of
burning fuel passes up through the cen-
tral part of the boiler and then is de-
flected downward around the sides after
hitting cither the cold-water drum above
or a cushion of cooler gases next to the
drum. It then passes up through the
outer row of tubes around the upper
drums and then through the air pre-
heater to the stack.

The boiler itself consists of a water-
jacketed blast pipe into which the feed
water is fed. This water then passes
to the upper drum as shown. This drum
consists of mild-steel headers, with a
central portion forming a steam cham-

'ijlverizerand
Blower

Fic. 4. E.I ECTOR Form of Stack

the boiler, after which it passes to the
steam main.

Combustion starts as the mixture
leaves the burner, the coal-dust particles
burning instantly, and the fine ash is
carried off as dust. The heavier particles
catch fire and continue to burn owing

into one solid mass from top to bottom
and are only prevented from melting
down entirely by the cooling action of
the tubes which they Inclose. When the
molten ash builds up to such a thickness
that the tubes cease to exert sufficient
cooling effect, it then drops to the bot-

394

POWER

September 12, 1911

torn of the lining and into the ashpit in
pieces about the size of a marble. This
action seals all joints or cracks in the
setting and prevents leakage. The intense
heat to which the inner row of tubes is
subjected circulates the water very rapid-

joints frequently caused trouble. In the
main steam lines, globe valves are al-
most invariably used instead of the large
gate valves used in America.

There has been recently introduced
in England a form of gate valve known

■iabi.p: 1. KKsn.TS of tf.sts on hi;ttixi;t(in iioii.i:r

I)

^ST

S„

T„ AKR

CAS-

Wki.sh

(Uifton

Antlira-

Bituminous

and

EUes-

Part-

cite

Nutty Slack

Kersley

mere

ings

Pickings

Duff

Dutt

14 . 33

23 . 00

21.12

22 . 58

21.30

19.92

12 64

32.55
0.99
52.13

20.00
57 ' no

26 . 46
3.13
52.42

27 . .38
0.85
.50 . 04

27.68
0.95
51:02

22.94
0.76
.57 . 14

11 66

0 . 99

Fixed carbon

75.70 ■

(B.t.u.)

11,S70

10,7011

11,250

10.098

10,494

11,088

12,276

l-'oiinds of water evaporated

Fahrenheit

12,29

1 1 . 08

pounds 1"' M'- II" ti

16.5

164.5

.„ .-

.•\verage ti-miM uuun l'.isi-.s

escaping liuni huiki. de-

580 750

592 . 7

658 8

558 . 3

587 . 5

603.7

560 3

Average temperature feed

water, degrees Fahrenheit -

60

64

i>7 , 2

897

2,733

1.020

1,179 2

6,828 . 6

17,307

6,55(1

7,984

7,348.1

8,803.6

8,471.4

9,217

Equivalent water evaporated

8,714*

22,374 1

8,476 8

10,290.4

9.437 . 2

11,321.4

10,909.5

11,776 4

7.61

6.33

6.418

6 . 635

6 111

6.401

6.986

7 . 36

Pounds of water per pound of

9.71

8.18

8.309

8 726

7.975

8.40

9.218

9.48

Thermal efficiency ba.sed on

79

66

75

74 . 9

Percentage of moisture in coa

during test

3.85

3.85

15.6

""

..4

*NormaI rate. tHigh rate.

Note. — Temperatures range from 150 to 200 degrees less tluit
heater. Heat returned to the furnace by air blast.

tlie i'bove when past ttie air

ly and there is, therefore, very little
scale deposited in these tubes, making
them less liable to failure than the other
tubes.

The amount of steam generated can
be regulated by adjusting the supply of
coal and air to the pulverizer. With
the air preheater, it is said that coal
with 15 per cent, or more moisture can
be burned with ease. The pulverizing
and grinding are said to require a power
consumption equivalent to 3 or 4 per
cent, of the boiler capacity.

Table 1 gives the results of some tests
on this type of boiler. Attention is
called to the high ash content of the
coals used and also to the moisture in
the third test.

Steam Piping

In general it may be said that the
steam-piping systems in European power
plants are of inferior design to those
in our large central stations, but, on the
other hand, they are usually kept in
excellent repair. European practice dif-
fers in several particulars from that in
America. For instance, no cast-iron or
semi-steel fittings are used where the
pressure exceeds 100 pounds, with the
exception of some very old plants in
the north of England. Above 100 pounds
pressure, cast steel is invariably used.
The bends used in these pipe lines were
of very poor design, and leaky steam

as the Hopkinson-Ferranti valve, which
has received wide application and is
shown in Fig. 3. It embodies the well
known principle of the venturi meter.
The velocities are increased in the cen-

faces are also reduced in size; hence
are less liable to distortion. As the
valve seats are small, this valve may be
used to throttle the steam when open-
ing up, rendering unnecessary the by-
pass valves common to the large gate
valves. When the valve is opened it
draws up a throat piece which when
full open forms a continuous venturi
tube and prevents eddying in the throat
and dirt from getting under the seat. This
class of valve can be used on steam
lines where the velocities do not exceed
6000 feet per minute, but it is question-
able if it could be used on steam lines
to turbines where extremely high steam
velocities have been obtained.

BOILER-FEED PUMPS

In Germany and in other parts of the
Continent turbine-driven centrifugal
boiler-feed pumps have been adopted
extensively; turbines of the Curtis or
the Electra type being generally used to
drive them. One variation from Ameri-
can practice is that instead of exhaust-
ing these small turbines into feed-water
heaters, which are seldom used, the ex-
haust is carried to one of the lower
stages of the main steam turbines; other-
wise they are run condensing. In Eng-
land the vertical boiler-feed pumps of
the Weir type are used almost exclu-
sively, and with very satisfactory re-
sults. Improvement has been made on
these pumps by the use of thin sheet-
tpetal valves for both water suction and
discharge. These valves resemble close-
ly those used on the Leyner air com-
pressor and the new Mesta blowing en-
gines, manufactured in this country. The
writer was informed that these can be

Fig. 5. Wolf Loco.mobile

tral portion of the valve so that the size
is reduced to one-half the regular pipe
size, while the contour of the passage
on the delivery side reduces the \'eIocity
and restores the pressure. The flat valve

operated at very high speeos
under ordinary conditions they
hold tight but last for some
properly faced before being put
pump.

and that
not only
time if
into the

September 12, 1911

POWER

395

Economizers
Economizers are used almost exclu-
sively in Germany in connection with all
classes of boilers and are also used very
largely in England. In the latter coun-
try tubular boilers of the Galloway and
Lancashire types are still largely em-
ployed, and where such boilers are in-
stalled the economizers are a decided
advantage. Very few feed-water heaters
were noticed.

CO: Recorders

These are to be found in almost all
the Continental boiler rooms, and the
firemen seem to watch them very closely
and interpret the results shown. The
type used is an improvement over those
which have been introduced in America
and apparently needs less attention. The
firemen, however, have a second check
placed on them by the installation of a
recording instrument which shows the
condition of the draft in the fire and in
the chimney breeching. This combined
with the COl- recorder gives a better
record of the quality of firing than if
the recorder alone were used, for most
any degree of CO. can be obtained by
choking the draft and working the boiler
light. Recording gages are also in-
stalled for recording the boiler pressure.

Water Softeners

Water softeners are extensively used
in all large European power plants. The
engineers believe that it is more eco-
nomical to remove scale by some me-
chanical or chemical means before it
is put into the boiler than to remove it
from the tubes after it has had a chance
to settle.

Chimneys

In England one soon becomes familiar
with the tall brick chimney which seems
to pervade the whole manufacturing sec-
tion of that country. In Germany these
are also used extensively, but they dif-
fer in appearance from the English
stacks as water towers are usually placed
about half way up the chimney.

In Germany a new system of mechan-
ical draft has been largely adopted by
the Allgemeine Elektricilats Gesellschaft
and other contractors for power plants
developing electricity where reliability
Is absolutely essential. This system has
been patented by Dr. Hans Cruse, and
one of its applications is shown in Fig.
4. It consists of an ejector-formed stack
40 or 5f) feet high. Draft is obtained
by blowing cold air through a pipe which
discharges upward at the throat of the
chimney, thus forming an air ejector.
This air is supplied by means of a motor-
nr turbine-driven fan. As the air passes
;r the chimney to the throat it becomes
cated and expands, thus increasing its
'.locity.

The advantages claimed for this sys-
•cm are as follows: The fan handles

only cold fresh air, hence is not sub-
ject to deterioration from the destruc-
tive flue gases. It can be of efficient
design and can be located in a place
accessible for cleaning and for quick
repairs. It does not require water-
cooled bearings. It has to handle only
small volumes of air at comparatively
high pressures and therefore can be
run at high speeds by standard and vari-
able-speed motors. The draft can be
regulated by varying the motor speed.
The power consumption amounts to
about 1 per cent, of the fuel burned.
The cost of installation is about the same
as for induced-draft outfits, and the ap-
paratus would seem to be well adapted

The engine is of the compound type and
is placed on a saddle riveted to the top
of the boiler shell. The high-pressure
cylinder is in the smoke flue and is
jacketed by the hot gases. The low-
pressure cylinder is jacketed by the
steam in the boiler and this jacket space
acts as a steam dome. The steam is
led from this portion through suitable
piping to the first superheater, directly
in front of the boiler tubes, and as these
tubes are short the gases leave at a
high temperature, making a high degree
of superheat possible. This superheated
steam passes directly through piston
valves, controlled by an automatic gov-
ernor, into the high-pressure cylinder.

TABLE J. WOLF LOCOMOBILES. FHO.M OFFICI.\L TJ

:STS

Pounds of

Pounds

Coal at

Steam per

13,500

.super-

Brake

B.t.u. per

hi^l.

Brake

Horse-

Pound per
B.H.P.

Steam

Degrees

Horse-

power-

Teste-i by

Date

Pressure

F.

power

lioiir

Hour

I'ATKNTKI) St PK.RHKATED CuMPI

rxD Locox

..HII.F.S

viTH Condenser

MiKileburg Boiler .Association.

Professor ilulermuth

Profe.ssor I^wicki

Magdeburg Boiler .Association.

Dec. 2. 1SI)4
.Ian. 11. 19(14
.Vpr. 26. 1901
Nov. 29. 1904

176 Rase

200
200
2.V)
210

28S 9
203 .i

lOS .T

10 .S
11.43

11 66
1 1 43

l.SS
1.345
1 37
1 4S4

I PEKllEATED CoMPOlND I.niDMDHIT.ES. .NoNCONDEX.SlNG

Magdeburg Boiler .\s,socialion. .lul.v 20, 190.'>
Magdeburs Boiler .Association. .May 23.1903

<l PERHEATEI) TaNDEM I.OrOMOnil,KS WITH Dm HI.F Si PEKH

AND Condenser

Koyal Inspection
.Magdeburg

Professor Jesse, CI

l)urg

H. .Malliol, Brussels.

Iidy 20. 190.-1
une 3. 1904

180 gage
180 gage
72 . 6 gage

10 9
10.29
10 8

1 ,32
1 23
1..33

to furnaces where coals high in sulphur
are burned.

The Locomobile

The great economy accompanying the
use of highly superheated steain was
early recognized by the Germans and
this led to the development of prime
movers of a type different from those
used in this country. One of these types
which continues to grow in favor is
called the locomobile. Fig. 5 shows a
section of a Wolf locomobile of the
latest type, which consists of a boiler
fitted with an internal furnace and short
fire tubes, although for certain grades
of fuel an external furnace of the dutch-
oven type is recommended. This boiler
is so constructed that the furnace tube
sheets at both ends and the nest of tubes
between them can be withdrawn for
cleaning by breaking the bolted joints
at the front and rear heads. This con-
struction might be objected to in this
country, but it has given no trouble in
Europe. Steam pressures nf from I. SO
to 200 pound? per square inch are usual-
ly carried in these units so that large
ratios of expansion are possible. The
outside nf the boiler Is heavily lagged.

Jacketing the cylinder by hot gases
and using superheated steam reduce
the cylinder condensation to a minimum;
hence the steam is used very economical-
ly in this cylinder. The exhaust from
the high-pressure cylinder passes into a
second superheater, which is heated by
the gases after having passed through
the first superheater. Further econcny
is effected by providing a condenser, the
air pump of which is usually driven di-
rect from the engine shaft by an ec-
centric or, on large sizes, by a motor.
The wasteful steam-driven boiler-feed
pump has been replaced by a small
pump, also driven from the main engine
shaft by an eccentric. An injector is
provided as a relay. The feed water
passes through a feed-water heater
placed in the exhaust pipe between the
low-pressure cylinder and the condenser.
Many of the later units have electric
generators direct connected to the engine
shaft. Platforms are provided around
the engine and all parts are easily ac-
cessible for oiling, cleaning and repairs.

These units have shown remarkable
economy, due to the following factors:
A reduction of air leaks in the setting
by having the furnace and superheaters

396

POWER

September 12, 1911

inclosed in the boiler shell; the use of
highly superheated steam in both cyl-
inders; the adoption of the compound en-
gine with condensers and the use of high-
pressure steam; the efficient jacketing
of the cylinders; the elimination of al-
most all steam-pipe lines, and an efficient
boiler-feed pump arrangement combined
with heating of the feed. The great
saving in floor space should also be
noted.

The writer recently made inquiry re-
garding one of these units for laboratory
work and received a proposal from R.
Wolf, of Magdeburg-Buckau, Germany.
The estimate was for one Wolf patent
superheated condensing tandem locomo-
bile with two superheaters and a boiler
pressure of 176 pounds gage, the engines
were to have balanced piston valves with
a shaft governor, and a speed of 220
revolutions per minute. The capacities

were to be: Economical load, 28 brake
horsepower; maximum load, 45 brake
horsepower; temporary overload, 54 brake
horsepower. The engine was to be pro-
vided with a belt wheel. The guarantee
was as follows: Consumption of coal
between economical and maximum load
not to exceed 1.52 pounds per brake
horsepower per hour with coal having
a heat value of 13,500 B.t.u. per pound
and less than 5 per cent, refuse; the
steam consumption not to exceed 11.66
pounds per brake horsepower per hour.
Delivery guaranteed within three weeks
of order.

This would correspond to a unit of
about 40 indicated horsepower in
America, and the guarantee compares
favorably with the results obtained on
large turbine units. When the load fac-
tor is bad and where absolute reliability
and constant speed are essential, such

installations are much superior to suc-
tion-producer plants. The price quoted
was, roughly, S2750 f.o.b. Hamburg and
packed for foreign shipment.

Other forms of these locomobiles are
provided with compound cylinders which
are jacketed by the steam in the steam
domes instead of the gases leaving the
chimney.

Recent results of tests on Lanz loco-
mobiles at the Brussels exhibition showed
with one unit of 178 brake horsepower, a
coal consumption of 1.33 pounds per
brake horsepow^er per hour, and a steam
consumption of 11.69 pounds. On a
larger unit of 235 brake horsepower the
coal consumption was 1.286 pounds per
brake horsepower per hour and the steam
consumption 7.068 pounds. These re-
sults confirm those given in Table 2,
which was made up from tests by a num-
ber of authorities in Europe.

Steam Engine Lubrication

During the last seven years the writer
has been connected with a company which
builds engines and has come in contact
with many troubles due entirely to poor
lubrication. In numerous cases the
trouble was not due to the price paid for
the lubricant or the quantity used, but to
the fact that it was not suitable for the
conditions of the particular engine on
which it was to be used.

The lubrication of the pins and jour-
nals of the engine can best be accom-
plished, perhaps, by installing a gravity
oiling system, for there has lately been
put on the market an oil filter and pump
which can be placed near the valve-gear
side of the engine and driven from the
rocker arm. This arrangement pumps
the oil from the receiver below the floor
up into the filter; from the filter the oil
is pumped into a standpipe on the frame
of the engine which gives sufficient head
to force the oil to the bearings and pins.
For small- and medium-sized units, this
makes a satisfactory arrangement, as the
entire apparatus is so located that the
operator can see what is going on with-
out leaving the engine room.

There are some locations where the old
gravity system may be desirable. The
main point that the writer wishes to con-
vey is that some kind of a system should
be installed whereby the bearings and
pins of the engine can be practically
flooded with oil; by so doing hot pins
and journals can be eliminated. The
engine will run two or three times longer
without keying up (which proves that
the pins and journals are not wearing
rapidly) than would be the case if cups
were used and drops of oil were fed to
the pins and journals.

Another point in favor of the flooding
oiling system is the fact that if from any
cause a little dirt should get in the bear-
ings or on the pins, the large quantity

By R. D. Tonilinson

1 arioiis systems for exter-
nal hibrication are dis-
cussed. Cylinder lubrica-
tion trouble is often reme-
died by changing the point
of feed. Price is no guide
to suitability of a lubri'ant.
Wet steam is a soioce of
trouble.

'Abstract of paper read at annual meeting
of tlie Institute of Operating Engineers, New
York. September 2, 1911.

of oil passing through would wash the
dirt out without doing any harm. On the
other hand, if only drops are used, the
probabilities are that the pins and jour-
nals would run hot and cause more or
less serious damage if the attendant did
not happen to notice them in time to take
care of them. Hot pins or journals, like
a fire, will soon get beyond control if
not discovered in time.

There are many varieties of oil filtei.
some of which operate better than others,
but the main point to look out for is the
size of the filter. It should be large
enough to allow sufficient time for the
oil to filter properly while passing
through.

Cylinder Lubrication
Cylinder lubrication is one of the most
difficult problems with which the engineer
has to deal.

A great majority of cylit)der and piston
troubles are due to improper lubrication,
frequently because the cylinder oil used
is not suitable to the conditions.

Variation in the temperature of the

steam is an important factor, and a still
more important one is the quality of the
steam entering the cylinder. There is a
great deal less trouble with the high-
pressure cylinder than with the low as
the steam is drier. The majority of cyl-
inder oils will not properly perform their
function if the steam is wet. Trouble
from wet steam is much aggravated
where large engines run for any length
of time on light loads. The low-pressure
cylinder steam is very wet and unless
the cylinder oil used is compounded
heavily with animal oils it will not form
a film on the cylinder walls. Price is not
a good guide to go by, for it frequently
happens that a very low-priced oil. but
one which is properly compounded for
the service, will absolutely cure troubles
which high-priced oils utterly fail to
affect.

It is sometimes difficult to get a spe-
cial oil. for many of the oil companies
insist on supplying the regular oils, which
they manufacture in large quantities.
They seem disinclined to compound spe-
cial oils to meet special conditions. There
are exceptions, however, and satisfactory
oils can be obtained if the user goes
about it in the right way. A cylinder
that shows evidence of improper lubrica-
tion, should be treated much the same
way as any sickness; a competent engi-
neer should diagnose the case and pre-
scribe the proper oil to meet the condi-
tions.

It frequently happens that the trouble
is not with the oil itself but with the
method of introducing the oil or the place
where it is introduced. There are cases
in which the oil pump or lubricator at- ,
tachment was changed to some point on I
the steam line — sometimes 4 or 5 feet i
from the cylinder — with good results.
This gives an opportunity for the oil to
become thoroughly mixed with the steam i

September 12. 191 1

POWER

397

before entering the cylinder. There are
other cases in which the oil should be
introduced close to the cylinder; it all
depends on the conditions. An expert for
one of the largest oil companies in the
country told the writer that when called
in on lubricating troubles he often meets
with success by changing the manner of
introducing the oil into the steam and
the place of its introduction.

The whole matter simply reduces to a
careful study of the conditions that exist
.Tnd experimentation with the various
kinds of oil and the methods of applica-
tion until the proper conditions are se-
cured. This, any intelligent engineer can
do.

A great deal has been written and said
ut the necessity of just the proper

quality of iron in a cylinder to make a
piston run propc-ly in it, and there is no
question of the advantages of the iron in
the cylinder and bull ring being of the
proper degree of hardness, etc. How-
ever, the writer has seen many soft-iron
cylinders operate successfully without
rapid wear with the use of properly se-
lected cylinder oil that maintained a film
on the surface of the cylinder

One point in connection with the sub-
ject of cylinder lubrication to which I
wish to call the attention of all engi-
neers, is the fact that it is quite common
practice to reduce the quantity of cylin-
der oil used to the least possible amount
necessary. This cuts down the oil bill,
but in many cases it increases the in-
ternal friction of the engine, so that it

requires much more steam to turn it and,
hence, increases the fuel bill. Engi-
neers should remember that it is not the
reduction of the oil bill or any other one
item in a plant that counts; it is the re-
duction of the total cost of operating th.;
plant that they should strive for. It is an
easy matter to economize on some single
item and by so doing raise the cost of
operating the entire plant. Many an en-
gineer, on taking charge of a plant, in his
desire to make a showing reduces his
help and supplies to an extent that shows
up fine for the first few months. But a
little later on he has found that the en-
tire plant had to be overhauled and a
large sum of money expended to bring
the plant up to its original standard of
efficienc\-.

Removing Emulsified Oil from Water

I'nless one has had personal experi-

,•-• with the difficulties met with in

.oving emulsified oil from condensed

.cr, he can hardly appreciate the per-

L-ncy with which the oil sticks to the

rcr. VCater which in the form of

,im has passed through the cylinders

J steam valves of engines and pumps

ricated with cylinder oil, carries with

ill the oil that has passed into the

^ iinders, some of it in the form of drops

or small globules of pure oil and the

r-jtiiainder in the form of emulsified or

ely divided oil in suspensiori. The

ulsified oil gives the water a milky ap-

:rance similar in appearance to water

• contains a quantity of air in sus-

■ --ion. In the case of emulsification this

:ky appearance does not leave the water,

when it is filled with air, and the oil

•not be filtered out by ordinary meth-

~ This finely divided oil must not be

V n fused with the drops of oil above

mentioned, which are often seen floating

'in the surface of water condensed from

'laust steam, as these drops of oil may

-ily be removed from the water by

iccting the mixture in a settling tank

11 which the water still carrying the

ulsified oil can be drawn off at the

bottom.

The removal of the emulsified oil to
render the water suitable for re-use in
Ihe boilers is the real problem. At present
there are three well known methods of
removing this emulsion, namely:

(a) Filtration through certain kinds

of natural sand or crushed
stone.

(b) Electrical treatment.

(c) Chemical treatment.

Each of these methods has its par-
ticular field, depending upon local condi-
tions and plant equipment. Only the
chemical method will be described herein.

The commercial name of the chemical
used in this proces.-. is ferric alum (ferric
ammonium sulphate l. This ferric alum
comes in the form of lumps or crystals

By Darrovv Sage

.1 .^nKill iiDioKiit Of jerric
alum aildcd to the 7<.aier
causes the oil to coai^ulatc
so that it is easily removed
i)i a sand- filled filter.

".VU.'iiinil "f iiapi-r \fM\ at nniuial nipi'ting
III' the Institute of Operating Kngineers, New
V<Mk, SeptemlMT 2, 1!)11.

having a peculiar bluish tinge which
turns to a brownish-yellow color after ex-
posure to the air. It is easily soluble
in water and this property is used to
introduce the proper quantity into the
water to be purified. From experience it
has been learned that about 4 pounds of
ferric aluin will successfully clarify 10,-
000 cubic feet of emulsified oil and water,
and if this water is recovered at the
rate of, say, 4200 cubic feet per hour,
the ferric alum should be added uni-
formly at a proportional rate. Not only
must the rate of flow of the water and
ferric alum be uniform, but care must be
taken to see that the chemical is thor-
oughly mixed with the water to be treated.
A convenient way of doing this is to
dissolve the necessary amount of ferric
alum to last about 24 hours in a barrel
of water and permit this solution to flow
or drip into the tank in which the re-
turn water is caught before it is pumped
to the filter, as will be explained later.
In making the fcrric-alum solution, care
must be taken not to produce loo strong
a mixture, as a saturated solution of
this chemical in water is very corrosive.
It should never be mixed in greater pro-
portions than 2 pounds to the barrel of
water of about .V) gallons and where
conditions will permit, less than this. As
soon as the fcrric-alum solution and the
water under treatment have been thor-

oughly mixed, a pronounced change can
be noticed in the milky appearance of
the water. It is caused by the action of
the ferric alum, which coagulates the
minute particles of oil suspended in the
water, and thus produces a change that
cannot be easily described but can be
quickly detected.

After the action of the chemical has
taken place the mixture is ready for
filtration.

A filter for this purpose can be made
from an ordinary tank partially filled with
coarse, clean sand which has sufficient
area to permit a flow not exceeding 15
cubic feet per hour per square foot of
sand bed. The sand bed should be about
2 or 3 feet thick and the sides of the
tank must extend above the top of the
bed a sufficient distance to provide a
separating space for the floating oil. Into
this filter the water treated with the fer-
ric-aluin solution should be pumped and
properly scattered about the surface of
the sand bed so as not to wash holes
therein and be allowed to pass out at
the bottom of the bed through screens
and perforated pipes to keep the sand
back. The emulsified oil being properly
coagulated, it will be caught by the sand
and froin the discharge of the filter clear
water practically free from oil will be
obtained. Where it is possible to arrange
the filter so that the overflow can be
caught, the drops of oil and coagulated
scum can be washed out of the filter by
s'mply shutting the discharge valve from
the bottom of the tank and permitting
the filter to overflow its sides. The float-
ing oil can in this way be skimined from
Ihe top of the lank at regular intervals,
but its use as a lubricant is not advis-
able. By this method the cleaning of the
sand bed can be materially postponed,
thus getting the equivalent of a longer
life out of the filter. VC'/h a filter as
above described, cleaning will be neces-
sary about every 30 days when working
up to its full capacity, it being assumed

398

POWER

September 12, 191 1

that there is no more than a normal quan-
tity of oil in the water which passes
through the filter.

The cost of operation of a filter plant
of this size is small compared to the
value of water saved, as the present
price of ferric alum is about 20 cents
per pound and the cost of saving 10.000
cubic feet of water would be 80 cents
plus the cost of the pumping and what-
ever slight attendance that is necessary
to operate the pump and keep it in good
condition.

Turbines for Japanese Navy

It is proposed to adopt for the Japan-
ese navy 25,000 brake horsepower of Cur-
tis turbines for two of the first-class
battleships, "Kawachi" and "Settsu," and
22,000 brake horsepower of Curtis tur-
bines for two out of three scout cruis-
ers. For the remaining scout, one set
of Parsons turbines of the same power
will be used and two sets of the
Parsons type of 20,500 horsepower
for two destroyers. The Irtest improved
Parsons turbines of 64,000 brake horse-
power are also to be installed for tnree
first-class armored cruisers, one to be
built in England and the remainder at
home, and a Curtis turbine installation
of the same horsepower is to be placed
in another first-class armored cruiser,
which will be built at home.

The accompanying engraving, repro-
duced from The Engineer, shows the
15-stage Curtis turbine for the battle-
ships "Kawachi" and "Settsu." The
diameter of the turbine is 12 feet at
its pitch circle, and it is designed for
27,000 brake horsepower at 270 revolu-
tions for the 7-stage and 25,000 brake

Special Crane for Coal

Coal handling at the plant of the
Toledo Railway and Light Company, at
Toledo, O., presented a peculiar local

a gantry electric-locomotive crane with
a boom of 40 feet radius, which is suffi-
cient to unload three gondolas without
moving the gantry. The crane also handles
coal from barges or canal boats lying at

COAL-HAXDLI.\C CkANIi

condition which was solved by the com-
bined gantry crane with the cantilevered
coal elevator shown in the accompanying
illustration. This plant is located on the
bank of the Maumee river, and the two

HT CO.MPANY

the wharf. It is mounted over the wharf
leg of the gantry and operates a one-ton
clamshell bucket which dumps into a 20-
ton hopper carried by the gantry. From
this hopper the coal flows to the con-

'■3 s-^r^-J

Curtis Turbine for New Japanese Battleships

horsepower at 245 revolutions for the
15-stage turbine. The latter consists of
six ahead wheels and one ahead drum,
carrying nine stages and two reverse
wheels. Reaction blading has been used
on a part of the drum and second-
stage astern wheel of all the Cunis
turbines to counterbalance the propeller
thrust by means of steam thrust, so that
the thrust shaft and collar may be made
comparatively short.

main-line tracks of the railroad are
alongside of the power house, between
it and the side tracks upon which the
coal cars must be placed.

To avoid tunneling below the tracks
an overhead handling system was em-
ployed which would permit unloading cars
at any point on the siding and the trans-
fer of their contents to the storage bunker
in the power house.

There was designed for this purpose

veyer boot, from which it is elevated to a
discharge spout which can be spotted to
fill any desired section of the bunker by
moving the gantry. Vi'hile the capacity
of the crane is about 80 tons per hour
and the conveyer 160 tons per hour, the
device is operated by one man located in
the cab of the crane where all the con-
trollers and operating levers are central-
ized. The cost of handling coal with
this machine is about 2.5 cents per ton.

September 12, 1911

POWER

A High Speed Cast Iron Flywheel

Average practice in the design of cast-
iron flywheels dictates an upper limit of
a mile a minute or 88 feet per second
for the mean rim speed. Since the hoop
stress in a revolving cast-iron ring is
given by

(/,•,•/ />,-,■ .ec.mjy;
I<>
the hoop stress in average flywheel prac-
tice is less than 800 pounds per square
inch. The tensile strength of cast iron
is about 22,000 pounds per square inch
and at first thought the factor of safety
of

2 2,000

8oo ~ -''^
seems ridiculous. Yet the occasional
bursting of a flywheel preaches caution
and deters engineers from adopting
higher speeds. It is known that the dif-
ference between simple theory and actual
practice is caused by four different
agencies:

(II The weakening of the rim by the
joints of sectional wheels;

(2) Casting stresses;

(3) The bending of the rim by the
forces in the arms;

(4) Flaws.

It is found by even approximate cal-
culation that the weakening effect of the
common form of joint is very great in-
deed. The author has never seen a com-
plete theory of flywheel joints which con-
siders the concentration of local stress
due to the action of the fasteners (links,
bolts or keys I, the influence of the bend-
ing moment and the action of shrink
links due to their initial tension beyond
the elastic limit.

Casting stresses depend not only upon
the design of the wheel but upon foundr\-
practice as well; they are uncertain, and
in many designs of wheel their presenci.
cannot be detected. The author remem-
bers a wheel of standard design which
while lying peacefully in the yard of :
foundry, pulled an arm off. near the huh
even before the wheel had been deliverc J
to the machine shop. To judge froiii
this one example, even no speed is too
high for a flywheel. Fortunately, such
a sad combination between poor design
and poor foundry practice occurs but
seldom.

The bending of the rim can product,
unexpectedly high stresses, particularly
in shallow-rim pulleys. These can be
mathematically determined, however, and
thus kept within safe limits. An ex-
ample will be given later.

Flaws furnish another valid reason for
using a high factor of safety. They are
similar to shrinkage stresses inasmuch
as they escape discovery so long as
the wheel is intact. They differ from
shrinkage stresses because flaws are
usually located by a post-mortem exam-

By W. Trinks

.1 17-/00/ uliecl dcsig)icd
for a rim speed of 10,000
feet per minute. It has no
rim joints (Did the spokes
are cast solid -uith the rim,
tnit free at the liiih ends.
11 cak)iess due to jiaws was
avoided by especially care-
ful foundry leork.

ination. Sudden changes of cross-section
favor the formation of flaws and should
therefore be avoided. A discussion of
the manner in which to avoid flaws by
correct foundry practice does not belong
in this article.

could be shipped solid from the works
of the builder to those of the user in
spite of the distance, about 65 iniles.
The absence of rim joints, of course,
eliminates the weakening effect of such
joints.

The eliinination of casting stresses was
quite serious. It is well known that, in
general, large solid-rim wheels are
shunned by engineers, not only on ac-
count of the difficulties of transportation
and erection but because great and un-
certain shrinkage stresses are found in
them. The illustrations show the vari-
ous features which were employed to
avoid these stresses. First, the arms,
while made solid with the rim, were not
connected at the hub; thus, they could
shrink independently of each other. Sec-
ond, the arms pass with long sweeping
curves into the rim and into the hub
section for the purpose of shoving the
sand of the mold sideways by wedge

Fic. I. Flywhkfl nEsir.Nin for a Rim Speed of 10,000 Fi:i:t per Minute

In the summer of 1910, the author de-
signed for the Mcsta Machine Company,
builder, and the Cambria Steel Com-
pany, purchaser, a flywheel with an out-
side-rim speed of lO.fKK) feet per minute.

The wheel is shown in Figs, 1 and 2.
It will be seen that there are no rim
joints. If was found that a 17-foot wheel

action and thereby avoiding surfaces
which could grip the sand and thus pre-
vent free and unhindered shrinkage. This
feature was made possible by splitting
the wheel into two wheels, bolted together
at the rim and connected to a common
hub. Third, the dishing of the arms al-
lows bulging out during the cooling of

400

POWER

September 12, 1911

the casting, if resistance should be of-
fered by the central core. It may be
mentioned here that the foundry did its
share in avoiding stresses, for instance,
by making the cores between the arms
soft and comparatively loose so that they
could not offer undue resistance to shrink-
ing.

The fourth weakening effect, namely,
flaws, may be mentioned in this connec-
tion. Splitting the wheel in two was
done with the intention of avoiding un-
duly heavy sections. "Soundness to the
core" is much harder to obtain in heavy
sections than in light or medium sections,
as explained in the various textbooks
and periodicals on foundry practice. Be-
sides, the gradual passage from the arm
section to the rim section tends to pre-
vent cavities in the casting.

VC'ith the shrinkage strains practically
eliminated, the determination of centrifu-
gal strains in the arms and in the rim
can be made with some accuracy. Since
a woeful amount of ignorance exists on
the distribution of forces in flywheels, a
review of the method of calculation will
probably be welcomed by "seekers for
the truth."

Imagine the rim of a wheel rotating
by itself — that is, disconnected from the
arms; then its diatneter will grow a small
amount. Next imagine the arms rotat-
ing disconnected from the rim; then they

deformation of both springs due to the
force under consideration. These data
together with the self-evident condition
that the force on both springs must be
alike (one being the reaction for the
other) make the calculation determinate.
A few words may be said about treating
the arms and the rim as springs. The
arms are straight bars and their deforma-
tion by direct tension is easily computed.
The rim presents more difficulties as its
deformation is made up of two com-

dlOOlkper

Centrifugal stresses only

Fig. 3. Diagram Showing Location of
Stresses

ponents: First, a reduction of the diam-
eter of the rim by the hoop tension which
balances the arm pull; second, a flexure
of the rim by the arm pull. All of these
calculations; namely, the computation of
the size of the gap. the stiffness of the
two springs, the rim-to-arm pull and the
resulting stresses, are thus purely a mat-
ter of applied mechanics; they offer no
fundamental difficulties, but are very

hoop stress, as computed from the for-
mula for a thin revolving ring, amounts
to 2150 pounds per square inch. On
account of the depth of the rim the bend-
ing by the arm pull does not increase this
stress materially. Thus the stress in the
rim near the arm is 2410 pounds per
square inch, whereas the stress midway
between the arms is only 2100 pounds
per square inch. The stresses in the
arms due to centrifugal force are also
small, amounting to 2390 pounds per
square inch near the rim and to 2010
pounds per square inch near the hub.
The material of the wheel (air-furnace
iron I showed a tensile strength of 30,-
000 pounds per square inch. Since the
design practically eliminates all casting
stresses, this wheel should be very safe
in spite of its speed.

Naturally, flywheels are intended to
store up and give out energy, which pro-
cess involves bending stresses in the
arms. In the wheel under discussion the
power to be transmitted was not speci-
fied by the purchaser because the vary-
ing temperature of steel in the rolls will
vary the power required between ex-
tremely wide limits. Therefore, the build-
ers reversed the method of procedure
and computed the greatest power which
can be transmitted by the wheel at a
given speed with a given fiber stress in
the arms. If the sum of centrifugal and
bending stresses is limited to 3000 pounds
per square inch in the arms, as indicated
in Fig. 3. the wheel can deliver or store
up power at the rate of 21,000 horse-
power. The builders felt satisfied that
the rolls or roll housings would let go

Fig. 2, Showing Principal Dimensuins of Flywheel

Torque - Fr
Bending Moments'
= ?\.and Fl,

Fic. 4. Illustrating Effect of Bending

Stresses

will also grow in length, but not as much
as did the rim. If both rotated separately,
there would consequently be a gap be-
tween the arms and the rim. In reality
there is no such gap, from which it
must be concluded that the rim pulls
the arms out and that the arms pull the
rim in. From the size of the gap and
the dimensions of the wheel the force
acting between ihe rim and the arm can
be computed in this manner. The arm
is a rather stiff spring with a certain
scale; the rim is a spring with another
scale; the imaginary gap furnishes the

tedious, because no general formula can
be employed.*

Undoubtedly an outer-rim speed of
10,000 feet per minute will be called
recklessness by many, and for their spe-
cial benefit the stresses found by the
above outlined method will be given.

The principal stresses have been en-
tered on the diagram in Fig. 3. The ideal

*?'tiunvon(l and I.anza tried (o derive ."tiu-Ii
formiilns (sp(> Tritmiiirlinns of A. S. M. K. of
the yoaiii l.sns to isn.'ji. .T. Goeliel gavi< a
completp derivation ip Z. 1). V. I). I. aiarcli,
l.'in.S). Iiut ills formulas, altliousli con-eol. aio
loo conipiicated for practical use.

before the wheel if any such amount of
power were required.

A few words should be said on the
subject of bending stresses in the arms.
because much confusion exists in the
minds of many engineers on this point.
Each arm is rigidly held at the hub, and
is more or less rigidly held at the rim;
it can therefore deflect only as is shown
in Fig. 4, presenting an inflexion point A
whose location depends upon the relative
stiffness of the arm and the rim. In
flywheels proper with deep rims the point
A lies near the middle of the arm. In

September 12, 1911

pulleys with shallow rims the point A
lies near the outer end of the arm. The
exact location of the inflexion point can
be mathematically determined, but the
process is tedious, and a skilled designer
soon learns to guess the location of this
point with considerable accuracy. Force
F, Fig. 4, times the radius r gives the
transmitted moment. This simple reason-
ing teaches that the bending at the rim is
frequently just as great as the bending
near the hub.

The outer rim speed of this wheel, as
before mentioned, is 10.000 feet per min-
ute, but this is by no means the com-
mercially attainable limit. Wheels with
plate walls gripping over a steel rim in
halves can be run safely at 15,000 feet
per minute. The simple formulas for
h op stress then are no longer applicable,
_ luse solid disks have taken the place
arms. We all know that properly de-
ed disks can be run at very high
.ds, the De Laval disk, for instance,
ning at a speed of 72.000 feet per
minute.

^'hile it is thus apparent that much
higher rim speeds may be used than
have heretofore been customar\-. it should
not be overlooked that commercial rim
speeds depend not only upon strength of
materials and design but also veo' largely
upon dollars and cents. Rotative speeds
in steam-engine practice have been mod-
crate, and low rotative speeds do not
pentiit high rim speed without exces-
si\e diameters of wheels. An extreme
-e will illustrate the point: An engine
eh is direct-connected to a tin-plate
and runs 30 revolutions per minute
Id have to be equipped with a 160-
• diameter wheel to attain the before
■uioned rim speed of 1.5.000 feet per
• ute. Such a wheel would be all arms
or all plate without any rim and would
be preposterous. Electric motors and
hiuh-speed gas engines, on the other
hand, can make use of high peripheral
speeds. The proper rim speed for fly-
wheels has, therefore, ceased to be solely
a question of strength but must be de-
cided from case to case.

\\ hy jimniy Was Refused

a License

By J. E. Terman

James Thomas, a young man of
24, was a technical-school graduate,
but having no financial resources he was
compelled to start in at the bottom of the
ladder. In the beginning he was making
the armature repairs for a street-railway
system in the South and was called up-
"" to run the engines when either of the
engineers was absent. Here was
my's opportunity to become familiar
with steam engines; he had had practical
experience with boiler operation.

The town in which the plant was lo-
cated hud a municipal license law for

POWER

engineers, and, although Jimmy was
aware of this fact, he never thought that
the conditions under which he was op-
erating the plant demanded a license.
One day he received a notice to report
to the board of examiners, with threats
of dire penalties should he attempt to
further operate the engines without a
license. Jimmy, greatly disturbed by the
receipt of this notice, consulted the chief
engineer. The chief told him that all
of the members of the board were mere
starters and stoppers and that he need
not fear any puzzling questions from
them. Jimmy skimmed through a text-
book on the steam engine to refresh his
memory on some points of engine design
and operation.

On the day appointed for the examina-
tion, Jimmy came before the board of
examiners. The questions were all of a
very practical nature, such as the correct
location of the water line in a boiler,
how to set a safety valve, etc., and
Jimmy found no difficulty in answering
them with entire satisfaction, until finally
Shaffer, one of the throttle twisters,
asked how the clearance of a steam en-
gine could be determined. Jimmy felt
very thankful that the professor at col-
lege who had taught him this subject
had been thoroughly practical, and he
remembered the simple method of meas-
uring the clearance of a steam engine of
the Corliss type when the valves and
piston were tight (by placing the engine
on the center at the end where it was de-
sired to measure the clearance and pour-
ing a measured quantity of water into
the steam port until the clearance space
was filled). Jimmy was sure that the
simplicity of the thing would win the
examiners so he described this method
in answering the question, supplement-
ing it with the information that all spaces
might be measured by removing the cyl-
inder head and in this way the clearance
could be calculated.

Jimmy had progressed so well up to
this point that he was quite taken back
when Shaffer shook his head and said
that his answer was wrong. Shaffer said
that to correctly determine the clearance
on any steam engine the crank should
be placed on the center and the piston
rod disconnected from the crosshead and
then the piston moved until it struck the
cylinder head; the space through which
the piston moved would he the clearance.
Jimmy stated that this kind of clear-
ance was commonly termed striking
clearance, and that the questioner should
have specified striking clearance if that
was what was wanted; that if any engine
builder was asked regarding the clear-
ance of an engine, he would give the total
amount of cubic space left behind the
piston in the cylinder and in the ports,
when the engine was placed on the cen-
ter, and would express il as a percentage
of the displacement of the piston in
making a stroke.

401

Farrin sided with Shaffer, but Rashley,
the third member, sided with Jimmy, who
was treated to an edifying discussion on
what was steam-engine clearance by the
three members.

Jimmy had gained confidence by listen-
ing to the harangue of the board mem-
bers over the subject of clearance, and
boldly stated that he wanted a first-class
license. Shaffer held up his hands in
horror at the idea and said that if they
should give a young electrician a first-
class license, they could give no excuse
when a man who had been passing coal
and firing boilers for ten years should
come to them and be granted only a third-
class license.

Jimmy was firm, however, and told
Shaffer that he did not "give a hoot"
what kind of excuse they gave such a
man; it was a first-class license or noth-
ing with him, unless they could furnish
some good excuse for witholding it. As
the examination was the only basis al-
lowed for determining the qualifications
of an applicant for a license, and as
Jimmy had answered all of the questions
satisfactorily except the one that the
board itself could not agree upon, he
had very much the best of the argument.
Rashley at this point beckoned Jimmy
to step out in the hall with him, where
he told Jimmy that he knew the street-
railway people well, and he did not want
to inconvenience them hy preventing
Jimmy from operating the plant when
necessary. He said that while he felt
that Jimmy should have a first-class
license on the strength of his examina-
tion, he wished that he would consent
to accept a second class as the other two
examiners were opposed to technical
graduates, and he felt sure that they
would never consent to issue a first-
class license.

This matter of objecting to him on ac-
count of his education made Jiminy
"hot," and he returned to the room and
told the examiners that it was a first-
class license or none. Shaffer said, "All
right, young man, you will get none, and
if you are caught operating that plant
again you will be arrested and it will
go hard with you." Jimmy well knew
that, legally, the license law was about
as strong as tissue paper, and he now
had all of his Irish aroused, so he told
Shaffer where he could go; that he pro-
posed to operate the plant the first time
occasion demanded It. and defied them to
have him arrested. "I would like noth-
ing better," said Jlinmy, "than to get you
three engineers up before a judge and
jury to detennine your fitness to make
examinations for issuing dog licenses,
much less determining a man's ability
as to whether he can be Intrusted with
the management of boilers and engines."
Jimmy was never molested, although
he ran the plant many times after he
failed to get his license.

402

POWER

September 12, 1911

Heat Transmission in Boilers

Having been convinced from observa-
tion and investigation that a 4-inch tube
is too large to use in a horizontal tubular
boiler 15 feet in length, and that a large
part of the gases passes through the up-
per rows of tubes, I decided to make
some experiments with a view to ascer-
taining what improvements could be ef-
fected.

The boiler on which the experiments
were made was 15 feet in length, 5 feet
in diameter, and had forty-four 4-inch
tubes and was rated at 80 horsepower.
The grate area was 25 square feet. A
hole was drilled through the boiler front
at A, Fig. 1, to take the temperatures of
the gases after they had passed through
the tubes.

Another hole was drilled at B, Fig. 1,
through the side wall of the setting at the
back of the boiler to take the tempera-
ture of the gases before entering the
tubes.

After the boiler was put into regular
service a series of temperature readings
was taken. These readings are plotted
in Fig. 2. The average temperature for
the front of the boiler was 559 degrees
Fahrenheit and for the back 1388 de-
grees. This shows a drop in temperature
through the tubes of 829 degrees.

Since the volume of a gas at constant
pressure varies directly as its absolute
temperature it is well to note the differ-
ence in volume of the gases at points A
and B, Fig. 1. The ratio is nearly 2 to 1.
Now, if the volume of the gases at B
is twice as great as at A, the gases will
travel at twice the velocity at the back
end of the tubes that they do at the front
end. This being the case, the tubes are

By V. L. Rupp

.S',

)iii i{-imli

pipes plugged

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li'erc fitted into

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tubes of a hori-

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boiler. Tin

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..r 111.' Insllliitc (if (iperaliUK lOtiKineers. .Vpw
Yuik. SpptcnibiT 1, i:il1.

I decided to try to increase the velocity
of the gases through the entire tube
length and at the same time bring the

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II 11.10 11.20 11.30 11.40 11.50

Time

Fic. 2. Tempf.r.mures Before Pipes Were
Put In

gases into more intimate contact with the
heating surface. After some calculations
regarding the amount of gases passed by

'/'W^'VH

to be a neat fit in the tubes and allow a
1 '4 -inch pipe to pass through the center.
A quantity of old lJ4-inch pipe which
had been taken from the heating system
was lying in the stock room. This I had
cut into 15'_-foot lengths. One casting
was put on the pipe 12 inches from each
end and one in the middle; they were
fastened in place with small setscrews.
The pipes were then sealed at each end
with fireclay and put into the tubes. The
boiler was not cut out of regular ser-
vice after the pipes had been put into
the tubes and everything was done to
have the same conditions as when the
previous temperature readings, shown in
Fig, 2, were taken.

.\ series of temperature readings was
taken with the pipes in the tubes. The
lemperatures observed are plotted in Fig.
4. The average temperature at the back
of the boiler was 1531 degrees and at
the front, 486 degrees. This shows a
drop through the tubes of 1045 degrees.
It was found from a great number of
readings that if the average temperature
at the back of the boiler was over 1500
degrees, the temperature at the front
without the pipes in the tubes was 625
degrees or over.

The boiler was forced with a blower
to see how high a temperature could be
obtained at the front end. Fig. 5 gives
the results. The average temperature at
the front of the boiler was 552 de-
grees and at the back 1686 degrees.
This gives a drop through the tubes of
1134 degrees. One thing that should be
noted in particular in this test is that
after the temperature at the front reached
.'65 degrees it seemed to hang at that
point, although one of the readings of
the pyrometer at the back gave a tem-
perature of 1785 degrees. It was not
deemed advisable to force the boiler

Fir,. 1 Location of Points kt Which Tkv,p[:ratupe:> Wkre Observed

Fig. 3. Casting for Holding Pipes in
Tubes

much more efficient in the conduction of
heat at the back end than they are at
the front end, if the theory that heat
transfer is influenced by the gas velocity
is valid.

the tubes and finding that I could cut
down the tube area and still pass suffi-
cient gas to bum the required amount
of coal, I had a small casting made as
shown in Fig. 3. This was made so as

longer than 35 minutes as it began to
prime.

I was not fulh' convinced that the im-
provement observed was due entirely to
the 1 '4 -inch pipes in the tubes as it

September 12. 1911

seemed possible that the restricted tube
area caused a more equal flow of the
gases through the tubes as a whole.
Therefore. I removed the pipes and in-
serted a small metal ring in the end of
each tube so as to give the same area
for the flow of the gases as did the pipes.
While this showed some improvement
over the conditions obtained with the
boiler unchanged in any manner, the re-
sults were not to be compared with the
i.Tiprovement shown by the use of the
-■'rrs in the tubes. The improvement was
at enough, however, to bear out the
-ory that the larger part of the gases
passed through the upper rows of tubes.
Boiler tests were run with and without
,' pipes in the tubes. The test with
_ pipes in the tubes showed a 10 per
nt. greater evaporation per pound of

POWER

The pipes have been in the boiler for
about two years and are in good condition
with the exception of about a foot at the

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IJM. 12.10 I2.J0 IE.30 12.40 12.50 12.60 12-70
Time '^-"

5. Temperatures Obtained When
Forcing Boiler

3.10 920 930 9.40

A-H. TJtio

Fic. 4. Temperature Readings with
Pipes in Tubes

coal. The boiler was not prepared in any
way for these tests; it had been in regu-
lar service for about three months before
the tests were made and was not opened
until after they had been completed.

Fig. 6 gives two sets of temperature
observations; the ones indicated by the

• I70O

back end. The fuel used was buckwheat
and no trouble was experienced in keep-
ing the tubes clean and free of dust.

\\ oodeil \.s. Stfcl BoiltTs

An accident to the machinery of the
steamer "Argyle" on her way from
Toronto to Whitby, on Lake Ontario, re-
cently disabled the vessel so that it was
necessary to remove the passengers and
transport them by rail to their destina-
tion. The following garbled report of
the accident in one of Toronto's daily
papers will no doubt be appreciated:

"The 'Argyle' is equipped with two

Fic. 6. Temperatures with and without Pipes in Tubes

dotted lines were made with the boiler
equipped with the pipes and the others
without. The sudden rise and fall of the
curves are due to the damper being
opened and closed, and to the coaling of
the fires.

wooden and two steel boilers, and the
wooden boilers, which arc the easiest
on the rest of the machinery, had been
used right through this season up to
yesterday.
"Yesterday morning, however, the

steel boilers, which cause much strain
on the machinery, were installed and this
was the cause of all the trouble.

"When the 'Argyle' started out the
greater vibration of these proved too
much of a strain on the rest of the
machinery, the trouble being made more
apparent owing to a wooden patch with
which one of them had been repaired.

"It was the added vibration of these
that jarred the valve pin out of place,
and thus cutting the steam off. caused
the machinery to stop and the side wheels
to come to a standstill.

"Had the steamer been kept going
with the valve pin out of place, the
piston rods would have knocked in
among the cylinders . and very serious
consequences would have resulted. As
soon as the passengers were landed the
six members of the engineering depart-
ment of twelve, who were on duty, were
at once put to the work of replacing the
steel boilers with the wooden boilers.

"Before morning they expect to have
made the change, and with a new valve
pin replacing the one that was shaken
out. the machinery will be in good work-
ing order again. With the wooden boil-
ers in place it is stated that the inachin-
ery works in first-class shape, and no
further trouble is looked forward to."

\\ ootlfn Knockoff I'hite

The accompanying illustration shows
the Corliss valve gear on one end of a
pumping engine. The knockoff cam A
was originally fitted with a steel plate
which, owing to the movement of the

■C-hOHF PlATH InsTKAII OF

Steel

valve gear, c.iu'-'ed a click just before the
catch block hooked on to open the steam
valve. ^X'hile this clicking did no harm,
it was exceedingly annoying.

In order to eliminate this noise, the
engineer of the plant removed the steel
knockoff plate, which was held in place
by screws, and substituted one made of
lignum-vitae. It did the trick, and shows
practically no wear. The dark portion of
the knockoff cam shows the new wooden
plate.

POWER

September 12, 1911

Gas Engine Cycles
By Cecil P. Poole

A cycle, in engineering, is any series
of operations that leaves conditions the
same at the end that they were at the
beginning. To illustrate this definition,
consider the case of the water which is
made into steam to drive a condensing
engine. If the water is taken from a
river, as is frequently the case, it passes
through the following series of opera-
tions or "events," as they are usually
called :

Being lifted from the river by a pump
and forced into a boiler; evaporation in-
to steam; expansion in the engine cylin-
der; cooling to liquid form in the con-
denser; discharge into the river. This
series of events forms a cycle, because
when the water gets back into the river
it is exactly where and as it was at
the beginning of the events.

A cycle, however, can be performed
without reference to materials or sub-
stances. For example, a steam engine
takes in steam, expands it, discharges
(exhausts) most of it, compresses the
remainder, and is then ready to take in
more steam and repeat the events. This
is a cycle also; because the engine is

■ Exnausf Vali'e ,,.„

A "

Fic. I. Beginning of the Cycle

in the same condition after driving most
of the expanded steam out and compres-
sing what is left as it was before tak-
ing in the live steam, after it has once
got into operation. The warming up and
filling the clearance before starting are
ignored because they are merely getting-
ready processes and do not form part
of the cycle, which is repeated over and
over after the engine is once started.

The cycle of a gas engine is not so
simple, because it includes both the gen-
eration and application of the driving
force. That is. it takes in the working
"fluid" (a mixture of gas and air), as it
is called, when it is in a state of im-
potence— that is, it cannot do any work
— and has to change the state of the
"fluid" by burning it and thereby setting

free the heat in it and producing a work-
ing pressure. The steam engine, on the
contrar\-. receives its working "fluid"
(steam) in a state of compression to a
high pressure and only has to apply
this pressure, which has been generated

cycle and the other class performs the
complete cycle in two piston strokes. En-
gines of the for.Tier class, therefore, op-
erate on the four-stroke cycle; engines
of the latter class operate on the two-
stroke cycle.

The Four-stroke Cycle

Remember that this discussion, for the
present, refers only to engines which
have trunk pistons working in single-
headed cylinders — that is to say, a cyl-
inder made with one end of the barrel
closed by a head and the other end en-
tirely open when the piston is not in it.
This type of engine will be recognized
readily upon looking at Figs. 1 to 6,

FiG. 2. The First Stroke (Suction); Dr.'wxtng in the Charge

in the boiler. The gas-engine cycle con-
sists of five events, as follows:

Admission, or suction;

Compression;

Combustion;

Expansion;

Exhaust, or expulsion.

These five events occur over and over.
in the order named, no matter what kind
of a gas or oil engine may be used. Dif-
ferent forms of engine perform the
cycle by means of different kinds of

although the pictures are largely dia-
grammatic.

In this form of gas engine, working
on the four-stroke cycle, one complete
piston stroke is devoted to taking in a
"charge" or cylinderful of a combustible
mixture of gas and air; the return stroke
compresses the charge; at the end of
this stroke, while the crank is passing
the dead center, combustion occurs, pro-
ducing the rise of pressure necessary
to give power to the engine; then an out-

Fic. 3. The Sccond Stroke; Co.v.pressing the Ch.\rce

mechanism, but the fundamental cycle
is the same in all of them.

There are two general classes of gas
and oil engines, grouped according to
the relation between the carrying out of
the cycle and the movements of the pis-
ton. Taking a simple single-acting en-
gine for the basis of the explanation, one
class requires four strokes of the pis-
ton in order to go through the complete

ward stroke is devoted to expansion, dur-
ing which the gases push the piston for-
ward and deliver power to the crank
shaft, and the succeeding stroke clears
the burned gases out to make way for
the next charge. To illustrate the cycle,
the familiar diagrams of the four strokes,
somewhat amplified, are presented here-
with.

In Fig. 1 the crank is shown on the

September 12. 191 1

p o v;' E R

405

inner dead center and the inlet valve
is just beginning to open to admit the
charge of gas and air. which begins to be
drawn into the cylinder by the suction of
the piston a moment later, as represented
at B, Fig. 2. where the inlet valve is
shown witle open and the entrance of the
charge is indicated by the two arrows.

While the piston moves from the posi-
tion A to that of C. the charge is drawn
in, and this constitutes the "suction" or
admission stroke; the inlet valve is shown
just about to seat, after which compres-

position to that of H, Fig. 5. the burned
gases escape to the atmosphere under
their own pressure, which is some 15 to
30 pounds above that of the atmosphere
when the exhaust valve first cracks open.
By the time the crank reaches the outer
dead center ( H, Fig. 5). the exhaust valve
is wide open, and as the piston moves
hack on the instroke again, the burned
gases are pushed out of the cylinder by
the piston, which is. of course, being
driven then by the flywheel if the engine
has onlv one cvlinder. The exhaust valve

Fig. 4. The Third Stroke; Expanding the Hot Gases

sion begins, as illustrated at D, Fig. 3.
(A comparison of the piston and crank
positions at C and D will show how de-
ceptive it is to consider gas-engine events
from the viewpoint of crank motion. Al-
though at D the crank has moved about
19 degrees from the dead-center posi-
tion C. the piston has moved about one-
fiftieth of its stroke. I

In moving from the position repre-
sented at D to that at E, Fig. 3. the pis-
ton compresses the mixture in the cylin-
der, the valves remaining closed, as
shown, and this is therefore termed the
compression stroke. Just before the
crank reaches the inner dead center at
the end of the compression stroke, the
igniter operates and the rise of pressure
due to combustion begins; this continues
while the crank is moving over the cen-

remains open, as indicated at /, Fig. 5,
until the end of the expulsion stroke,
which is the movement of the piston
from the position H, Fig. 5. to that of
J. Fig. 0; then it closes and the inlet
valve begins to open, ready to take in the
next fresh charge and begin a new cycle.

Summarizing the foregoing detailed ex-
planation, the four-stroke cycle consists
of taking in a charge during one outward
stroke. A, 8, C; compressing the charge
during one return stroke, C, D.. E; com-
bustion while 4he .crank passes the inner
center, E to F; expanding the heated
gases to do work during a third stroke,
F, G, H, and driving the burned gases
out of the cylinder during a fourth
stroke, H, I. J.

From this it should be clear that the
name four-stroke cycle (commonly mis-

accomplishes compression and another
pushes out the burned gases, and these
two results cannot be produced in the
same stroke.

In order to carry out the five events
within two piston strokes, it is necessary
to make three sacrifices: (1 I The charge
of gas and air must be pumped into
the cylinder instead of being drawn in
by the motion of the piston, because (2)
the admission of each fresh charge must
be accomplished within a very brief
space of time between the end of the
expansion stroke and the beginning of
the compression stroke, and (3( exhaust-
ing the burned gases must be done with-
in the same brief period of time.

The way in which these requirements
are commonly met in actual engines is
to open the exhaust port for a ver\- few
moments while the piston is at the end
of the outstroke and at the same time
force in the fresh charge under pres-
sure supplied by an outside pump. The
inrushing charge of gas and air (or
sometimes air alone! helps to drive out
the burned gases.

Figs. 7. 8 and 9 illustrate this method
of carrying out the cycle. At A, Fig. 7,
the piston is supposed to be just about
to begin the expansion stroke, the com-
pressed mixture of gas and air having
been ignited just as the crank reached
the dead center. The piston is forced
by the expanding gases from the posi-
tion at A to that shown at B, and when
\i reaches the latter position it begins
to uncover the exhaust port and relieve
the pressure in the cylinder. This prac-
tically completes the expansion stroke.

While the piston travels from the posi-
tion shown at B to the end of the stroke,
Fig. 8, and back again to the position C,
Fig. 7, the burned gases are discharging
through the port E and, at the same time,

aio)

Fic. 5. The Fourth Stroke; E.xpellinc the Dead Gases

ter, from the position shown at £, Fig.
3, to that shown at F, Fig. 4, the motion
of the piston during this brief period
being so small as to be negligible. This
completes the third event (combustion)
of the cycle and the fourth event, ex-
pansion, begins.

Expansion. like all the other events ex-
cept combustion, has practically a full
piston stroke of its own. It begins as
soon as the crank passes the inner dead
center IF, Fig. 4 1, and continues during
the outward stroke until the exhaust
valve begins to open, just before the end
of the stroke as indicated at G. Fig. 4.
While the crank is passing from this

called four-cycle) does not mean merely
admission, compression, combustion, ex-
pansion and exhaust, but means that
these iii'c events, constituting one cycle,
are carried out in four strokes of the
piston.

The Two-stroke Cycle
It docs not take much thought to make
one realize that the five events of a
cycle cannot be carried out completely
in one cylinder during only two strokes
of the piston. In the four-stroke en-
gine one outstroke is devoted to suction
and one to expansion, and both of these
events cannot be performed during a
single outstroke. Moreover, one instroke

Fig. 6. End of the Cycle

fresh mixture is entering through the
inlet port /. The mixture is directed to-
ward the cylinder head by a deflector D
on the piston head, to prevent it from
rushing across to the exhaust port E
and passing out «ith the exhaust gases.
When the piston has covered the in-
let and exhaust ports in its travel along
the instroke (position Ct, compression
begins, and during the movement of the
piston from this position back to the
position n at the end of the instroke,
the charge is compressed more and more.
When the crank reaches the inner dead
center, with the piston in the position D,
Fig. 7, the compressed charge is ignited

406

POWER

September 12, 1911

and burns while the crank is passing the
inner dead center; then the events just
described are repeated.

Summing up the foregoing description,
the cycle is carried out as follows:

Combustion in the position shown at

ment of ports used in large engines for
controlling the admission and exhaust.
Instead of covering and uncovering both
the inlet and the exhaust ports with. the
piston, only the exhaust is controlled by
the piston; the inlet port is provided with

E--' CO ^ <D)

Fig. 7. Diagrams Illustrating the Two-stroke Cycle

A: expansion while the piston travels
from the position A to that at B; exhaust
while the piston travels from the position
B to the end of the stroke and back to C;
admission during the same period with
e.\haust; compression during the instroke
from the position shown at C to that at
D. As these events all occur while the
piston makes one outstroke and one in-
stroke, the cycle is completed in two
strokes and the engine therefore works
on the two-stroke cycle.

the same form of valve used in four-
stroke engines. There are several ex-
haust ports, arranged in a belt around
the cylinder barrel as indicated at E
and when the piston has reached the end
of the stroke, the inlet valve begins to
open and admit a fresh charge. It re-
mains open until the piston on its re-
turn stroke has covered the exhaust

such as the control of the mixture pro-
portions, the use of separate gas and
air valves, etc., but so far as the es-
sential features of carrying on the cycle
are concerned, the two types operate
alike. Both work on the two-stroke
cycle and the timing of the various
events is practically the same in both ,
types.

A Bad Wrt-ck from a Small

Cause

By M. W. Utz

The accompanying photograph shows
the wreck of a 14x20-inch single-cylindei
horizontal gas engine of about 45 horseJ
power, which was used to drive a small
machine shop.

The front brass on the crank pin had
been cracked and a '_ix3-inch steel plate
had been bolted over it for reinforcement.
This plate and the brass broke, as shown
a; A, letting the connecting rod drop
down, and when the crank came around
the broken end caught against the crank,
buckling the rod slightly and breaking a
piece out of the cylinder 10 inches back
and down to the center line of the cylin-
der, as shown at B. The connecting rod
also broke a piece out of the piston 10
ii:ches back and nearly half way across,

Fic. 9. Arrangement of Ports for
Large Engines

From this description it should be
clear that the difference between the
four-stroke and the two-stroke cycles is
that the suction and exhaust strokes of
the four-stroke cycle are omitted in the
two-stroke cycle, the discharge of turned
gases and the admission of a fresh charge
both occurring during the very short time
while the piston is passing from the posi-
tion B. Fig. 7, to the position of Fig. 8
and back again to C, Fig. 7.

Fig. 9 illustrates the principle which
is commonly followed in the arrange-

Wreck of 45-horsepo\\ [:r (j

ports; then it closes and the further
backward travel of the piston compresses
the charge, exactly as described for the
double-ported engine of Figs. 7 and 8.

The only important differences in the
operation of the two types are that the
inlet port of the type in Fig. 9 is con-
trolled by a valve instead of by the
piston, and that therefore the charge is
admitted at the opposite end of the cyl-
inder from where the burned gases are
discharged. There are many minor dif-
ferences in the arrangement of details

as is partially shown at C. The broken
pieces of the cylinder and piston are
shown lying in the cylinder, except the
one piece out of the top of the cylinder,
which is still connected to the overflow
pipe of the jacket cooling water, and is
shown at D.

The engine was running on natural
gas, at 200 revolutions per minute, and
delivering about 13 horsepower at the
time of the accident. It had been in ser-
vice between four and five years up to
the time of the accident.

September 12. !PI 1

P O NX' F. R

407

Practical Points on Electric

W iring

By Walter C. Edge

Nearly ail etigineers understand ordi-
nary electric wiring, but there are sev-
eral methods that may be new to the
majority, or not thoroughly understood.

the main room are on or not, and it re-
quires only three full-lengtn wires in-
stead of the four used in the previous
method.

Occasionally it is necessary, for the
sake of economy, to have the lights con-
trolled by two switches instead of one,
so that either one-haK or all of the
lamps may be turned on, as required.

sockets would be used in this case, so
that the lamps in the main room may be
turned off individuallv if necessary-. Fig.
4 shows a method 'ised bv most engi-
neers for lighting the small room in-
dependintly of the Inrge one. Another
circuit is carried from the entrance to the
small room, making four wires instead

■mxiv^mm^- ■ ■'■" - - -■■■ ■■

Fic. 7

5«-/>c/? ^V)

1

O J Q O

O 0 0 0

#5-

Hic. 9

Fic. 10

■ Fuse Block

Fig. 2

O O J J J

V.

:> o 0

Fic. 15

Fig. Ifi

Fig. 5

Fig. 3

Fig. 1 .ihows the usual method of con-
necting the control switch when the
switch must be located at the opposite
end of ihe building from the entrance.
Fig. 2 shows a much bctt;r method, giv-
ing the same conttol with only three
wires, instead of four, running the full
length of the room.

In case there is a small room at the
end of a large main room, lor instance, a
cold-storage room, three methods of wir-
ing are av:iilable. Fig. 3 shows one that
is sometimes employed. The fault with
this lies in the fact that the main room
must be lighted first in order to get light
in the small room. Of course, key

^5titch

0 0 0^0

0 0 6.;

1

Kir,. I)

of two extending the full length of the
large room. The simplest and inost eco-
nomical way is to byoass ihi switch for
the main room, as shown in Fig. 5. By
wiring ihis way the lights mav be turned
on in ihe small rootri whether those in

In a case like this the way to wire them
is as shown in Fig. 6.

Conduit Work

Conduit work is largely icplacing the
open wiring, especially in l.irgc plants,
owing to the danger of fire from the
open wiring. There are so in.iny fittings
on the market now that this i.ind of work
can be done very neatly and easily.

The fittings that are uspd "he most are
shown in Figs. 7 to Mi inclusive. Fig.
7 shows an outlet fitting lor use in the
service line and Fig. H shows the corre-
sponding outlet fitting for use at Ihe end
of the service line. Fig. 9 shows an-
other typs of end nitinc Fig. 10 is an
exceptionally neat flttinn used generally
on the end of a branch line running
along the side of a beam or joist, neces-

408

P O W E R

September 12, 1911

sitating a bend at the end in order to
clear the wood.

Fig. 11 is a cross used for branches to
each side of the main. Fig. 12 shows
a tee for a one-way branch from the
main.

Fig. 13 illustrates a fitting called a
"bend!<iclc" used wherever a sharp bend
is necessary. The back of the ell screws
out, making it an easy matter to draw
the wir-.'s through.

Fig. 14 is a fitting used on the end of
an outside pipe run up the side of the
building. Owing to the fact that it is
practically impossible to enter wires in
a fitting like this after II is in place
on the end of the ripe, it is tlanged and
provided with a smail corresponding

Conduif

Fic. 17

flange which is screwed on the end of the
pipe. The wires are drawn through
the fitting separately and il is then bolted
to the other half of the tiange on the
end of the pipe.

Figs. 15 and 16 are boxes to take
snap switches; the snap switch is
screwed to the supporter shown inside
the box.

Upon starting on a job of conc^uit w-ork
the first thing necessary is a bending
device. There are thoroughly satisfac-
tory benders on the market, but if one
of these is not obtainable, a fairly good
bender may be easily made hy screwing
a tee on the end of a piece of pipe about
5 feet long. If '!•- or s^-inch conduit is
used, the bender should be made of I-
inch tee and piece of pipe.

In making a bend, accuracy can be ob-
tained by exercising a little care and

All bends should be made with as large
a radius as possible, so that the wires
may be drawn through without trouble.
If an offset is to be made in the conduit
it should be made with as gradual a
bend as possible.

When several circuits lead from a
fuse box, it is oest to take as many

Fig. 19

lengths of conduit as there are circuits
and start on all the circuits at the same
time, rather than run them separately, as
the bends can be made alike with greater
ease than is possible if put up separately.
The pipes must be bent at different dis-
tances from the fuse box in order that
they may all lie in the same plane. If
half of them turn one way and half the
other, there should be two pipes bent to
each length, one in each group, as repre-
sented in Fig. 18. If the pipes are to
be 6 inches apart, for example, the sec-
ond pipe must be bent at a point 6
inches beyond the bend of the first one,

Fig. 18

judgment. First place the length of con-
duit on the floor, putting tht end against
a wall or something solid; mark off the
required length and then slip the bender
on the pipe to within about 2 inches of
the marked point and bend the pipe
about 20 degrees, as represented in Fig.
17; let the bender slip back a few inches
and bend a little more, repeating this
until the proper bend is obtained.

Fig. 20

the third cne at a point ti inches beyond
the second one, and so on, as shown in
Fig. 18.

It is better when bending conduit to
put the mark on the floor than to mark
the pipe; then the pipe can be bent ac-
curately to the mark, as indicated in
Fig. 19, whereas the m.ark would be about
at a if placed on the pipe.

Considerable money can be saved by
using a little forethought in this kind
of work. For instance, if a light is to be
placed near a branch, the tec ran be used
for the light as well as the branch, as
indicated in Fig. 20, saving a condulet
fitting at the expense of a few feet of
conduit.

After the mech.inical work is complete
a steel-fishing wire is pushed through the
conduit, ihe conductors are fastened to
the end of it and are drawn through the
conduit, k little powdered soapstone
should be rubbed on the wires or blown
through the conduit to make the wires
slip through more easily.

The conduit should be grounded;
water pipe makes the bcbt ground, but
if no water pipe is close enough, a pipe
can be driven into the ground.

Kootenai Falls, Mont., to Be
Developed

Joseph A. Coram, owner of the water-
power site at the Kootenai falls, twelve
miles west of Libby, Mont., has an-
nounced his intention to at once proceed
with the organization of a company to
develop the immense water power there,
the object being to supply power not only
for Lincoln county industries, but for
some outside points also. The details
have not been entirely worked out.

The water in the Kootenai river, which
is the largest stream in Montana, ac-
cording to Government reports, goes
through the Purcell mountain gorge in
Lincoln county, Mont., in a succession.
of falls and rapids. The horsepower
that can be developed is estimated at
200.000 at low-water mark, and goes to
as high as 357,000 during high water.
There are no great engineering diffi-
culties to overcome in connection with
the work.

Hydroelectric Development of
Deertield River

Interests connected with a Connecticut
river power company have completed
plans for the hydroelectric development
of the Deerfield river, and have issued
S5,000,000 bonds to carry on the work.

The first stages of development will
provide for the generation of 25,000
horsepower. It is intended to dam the
Deerfield river in four places near Shel-
burne Falls, Vt., and build a reservoir at
Somerset, covering an area of about six
square miles. The water will be im-
pounded to a hight of 100 feet.

It is said that this undertaking will
ultimately cost S12.000,000.

Conservation of Water Power

Investigations of possible sites for de-
veloping wat T power on the public
domain are being pushed by the United
States Geological Survey, with resulting
withdrawals of land from entry where it
is found that valuable sites exist.

In July of this year 31,725 acres of
such land were withdrawn, including a
great number of power sites. No esti-
mate has been made of the horsepower
involved, but owing to the character of
the power sites withdrawn it is believed
to be very large. These July withdrawals
make a total outstanding area withdrawn
of 1.546,258 acres, based on the examina-
tion and recommendation of the Geo-
logical Survey, and involving thousands
of power sites and doubtless millions of
horsepower.

The withdrawals are made in aid of
proposed legislation by Congress which
shall provide for the fullest possible de-
velopment of these enormously valuable
properties and at the same time guard
the public interests. •

September 12, 1911

POWER

409

Cj'linder Oil for Hot Bearings

.My purpose is to show the advantage
having a clear idea of what to do in
-es of a hot bearing, so that precious
:Tients may not be lost.
t gave a little talk to my oiler and
J a can of cylinder oil set apart and
called it the fire extinguisher. The pos-
sibility of having a hot bearing seemed
lote, but I explained to the oiler that
inder oil would stand a consider-
V higher temperature than engine oil
J that if cylinder oil were applied
rnptly and in sufficient quantities the
■bitt might be prevented from running
-! the smoke stopped. If the trouble is
discovered in time the engine may be
continued in operation.

The opportunity to try the outfit came
sooner than I expected. I was working
with my back toward the engine and
the oiler was busy wiping a machine
when the oil-supply line got air-bound.
The sense of smell warned me that there
was a hot bearing around. I called for
the "fire extinguisher" and had the re-
serve oil cups running before the fire
brigade arrived, but it was the splash of
the half pints or so of the heavy cyl-
inder oil that absorbed the heat and
penetrated underneath the brasses and
stopped the smoking. Another engine was
started up, and on turning the distressed
engine over slowly I found that the brasses
would not take oil freely. The oil grooves
were cleaned oijt and the brasses scraped
a little.

A. Z. McLeod.

New York City.

'I'lirliintr Oiling 'trouble

I recently visited a steam plant just in
time to learn a new stunt. Several large
ftirbines were in operation, one of which
was giving trouble. The oil on both
ends of the bearing on the steam end was
running out in a stream. The turbine
was shut down and the operator was
trying to locate the trouble. He asked
nie what I thought of it, and I suggested
taking off the manhole cover on the ex-
haust end of the turbine. This disclosed
the cause of the trouble.

The two I'i-inch pipes used for a seal
supply had about fi inches of lime and
scale around them. Both pipes were
taken out, and the pipe which carried
the water from the bearing was found to
be plugged with scale, thus causing the
water to flood the bearing and mix with

the oil, and run out of both ends of the
bearing.

The pipe was cleaned out and put back
again, but the operator's troubles were
not over, as the water had gotten down
into the oil tank of the turbine, and be-
fore the machine could be put into opera-
tion several barrels of new oil were put
in the tank.

T. E. Jones.

South Bend, Ind.

Condemns License Law

It is to be hoped that in their efforts
to obtain license laws in the various
States, the engineers' associations will
show more sense and less bigotry than
the engineers in Philadelphia did when
they had a license law passed in that
city. The law in that city deprives men
of their right to earn a living and con-
sequently of their liberty as American

a marine nor a stationary engineers'
certificate, but if an engineer can pro-
duce good recommendations as to his
character and ability and holds a certifi-
cate as chief engineer of ocean steam-
ships or a first-class engineers' certificate
issued by the civil-service board in one
of our large cities, which entitles him
to take charge of any power plant in
that city, he should at least be entitled to
an examination without being compelled
to ask favors.

Of course, the engineers' associations
in this "City of Brotherly Love" have
been instrumental in having this absurd
law passed in order to debar others from
obtaining licenses, hoping thereby to re-
duce the supply of engineers and increase
their wages. How well they have suc-
ceeded is shown by the fact that many of
them work 12 hours for the same wages
paid to coal passers on American ships
for eight hours' work.

H. J. Leiper.

Philadelphia, Penn.

Straiglitening a Connecting

kod

An engineer, while tightening the stuff-
ing-box gland of a 250-horsepower Cor-
liss engine, got his wrench between the
gland and the crosshead. The gland was

Straichteninc Connecting Rod in a Lathe

citizens, if they have no influential friends
or will not ask favors.

Before an engineer is granted an ex-
amination for a liccn<;e to operate a steam
plant in Philadelphia, he must obtain
vouchers frotn two licensed engineers of
Philadelphia; engineers of any other part
of the United States are not good enough.
Two vouchers from employers are also
necessary, and a fifth voucher must be
signed by two other persons, testifying to
the good character of the applicant.

This would be all right for an ap-
prentice boy or a man who has never
passed an examination and has neither

broken and the connecting rod was bent.

The rod was placed between the cen-
ters of a heavy engine lathe, as shown in
the accompanying illustration. The rod
was heated to a cherry red, and a slight
pressure with a jack was sufficient to
bend it. After several attempts the rod
was straightened, then allowed to slowly
cool.

Before the rod was put back on the en-
gine, it was polished where it had been
heated and was apparently in as good
condition as before the accident.

C. A. GiLSON.

East Lansing, iMich.

410

POWER

September 12, 1911

Belt Ran to Side of Pulley

Some time ago I helped to set up and
start a new horizontal waterwheel, which
had a 60-inch pulley on the shaft. On
starting up the belt ran off 2\'i inches
to one side of the pulley, which had a
20-inch face, although the wheel shaft
was in line with the main shaft in the
mill.

After indulging in much thought and
worry, I took a steel tape and measured
the circumference of the wheel pulley
each side of the face and found it to be
about 3/16 inch larger on one side of
the face than on the other. The pulley
was turned half-way around and put back
on the shaft, the belt replaced and when
the pulley was started the belt took the
center as nicely as one could wish.
This, of course, was a crov/n-face pul-
ley and in turning up the face care had
not been taken to turn both sides of
the center to the same diameter.

Later, I helped to set up and start a
400-horsepower cross-compound engine
with a 32-inch-face flywheel. On start-
ing the engine the 30-inch belt ran off
one side of the flywheel about 3 inches.
There was some guessing as to what
caused it.

I found the flywheel to be the same
size on both sides of its face, but the
4-foot pulley on the jack shaft was 1/16
inch larger in diameter on one side of
the face than on the other. The pulley
was turned half-way around and put
back on the shaft. The next morning the
belt took the center of the flywheel and
the driven pulley, much to the surprise
of the other workmen.

James Mitchell.

North Adams, Mass.

Improved Stop Valve

Almost every valve used in pipe con-
nection in an engine room leaks more or
less. I have had troubles with valves in
boiler rooms which I found were caused
by faulty construction of the valve and
not poor management on the part of the
engineer.

In the ordinary stop valves I have
used the bearing surface between the
valve and its seat is one conical sur-
face and if the valve wears irregularly
or a bit of dirt gets in the bearing sur-
face, the valve will soon begin to leak.

To remedy this defect I designed the
valve shown in the accompanying illus-
tration, which is a sectional view.

The valve disk is made with an annular
inverted V-shaped groove which fits a
corresponding elevated surface on the
valve seat.

This construction gives the valve disk
and seat two bearing surfaces, so there
is little chance for steam leakage. If
the valve leaks at the inner surface, the
steam expands in the cavity of the groove

and forms a water packing, and thus pre-
vents further leakage.

The distance of the center of the groove
from the center of the valve differs
slightly from that of the center of the
valve seat's head. When the valve disk
is pressed against the seat on the outer
edge it springs in to some extent and
gives a uniform pressure on the valve
seat, thus keeping the valve nonleakable.
Yaekichi Sekiguchl

Tokio, Japan.

Daily Lofj Sheet

The accompanying daily log sheet is
a duplicate of those used by the Mobile
Light and Railroad Company, Mobile,
Ala.

The plant of this company is said to
be one of the most efficient in the South,
and its system of keeping records of all

operating expenses is the most complete
I have seen.

S. KlRLlN.

Mobile, Ala.

No Relief Valve on Heater

I took charge of a plant some time
ago in which a closed heater was used,
but there was no relief valve on the
heater or feed line.

I ordered a relief valve as soon as I
had looked over the piping, but the
owner refused to get it. He said that the
plant had run five years without one
and he did not see why he should get
one for me.

A few days later the owner sent me
out of the city to look at a second-hand
engine he thought of buying, the superin-
tendent running the plant in my absence.
After I arrived at my destination I re-

Mobile Light and Railroad Company— Daily Station Log

For 24 Hours, besinninr :4 a u io

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Daily Log Sheet for Power Station

September 12, 1911

POWER

411

ceived a telegram to "drop everything
and hurry back; break down."

Returning. I found the steamfitters tak-
ing down the heater and part of the feed
line. The superintendent had filled the
boilers to three gages of water before
shutting down for noon. He shut the
feed valve on the boiler and stopped the
feed pump, which pumped direct from
the city water; there was a check valve on
the discharge pipe next to the pump. The
feed line had filled up with cold water
■while the engine was shut down for dinner.
As there was plenty of water in the boiler
at one o'clock, he started the engines
without opening the feed to the boilers.
The engines had only run a short time
■when the exhaust going through the
heater caused the water in the feed line
and the heater coils to expand and burst
both the heater coil and the feed pipe.

I explained things to the boss and
showed him where a few dollars spent
for a relief valve would have saved him
the S250 that the shutdown cost him.

I now have a relief valve on the feed
line and one on the feed pump and a
spare one in stock.

W. V. Ford.

Norwich, Conn.

Isolated Plant Practice
This letter deals with the cost of pro-
ducing power in an isolated plant where
I was in charge some time ago, and is
submitted in the hope that it will

5 per cent, on a capital of S30,000, which
is the cost of the plant, the following
is obtained; Maintenance of equipment,
about S8.50, and interest ?4.2o per day,
or about $13 in round numbers, which
gives a total of .S60.55 per day. Now.
according to my figuring, the cost per
kilowatt hour for Fig. 1, is slightly
over 1.6 cents; for Fig. 2 and for Fig. 3
it was slightly over 1.3 cents.

One day about three years ago two
central-station representatives came into
the engine room and as they had per-
mission to look over our records for the
previous years, I gave them access to
the records dating from July 1, 1907 to
July 1, 1908. They spent two days look-
ing them over, but I have not seen them
since. Shortly afterward, the superin-
tendent told me they offered to furnish
current at 4 cents per kilowatt-hour.

The coal consumption per kilowatt-
hour is heavy; about 6 pounds. With
more efficient boilers, I could have made
a better showing.

A. C. KlERMEIER.

Philadelphia, Penn.

.\ Pump Experience

The action of a 400-horscpower triple-
expansion engine driving a hydraulic
dredge puzzled mc for a time. It was
fitted with a throttling governor and un-
der normal load turned over about 200
times per minute. The engine was di-
rectly connected to a centrifugal pump

the vanes and churn, reducing the wheel
resistance and causing it to act much the
same as the drivers on a locomotive when
slipping under a heavy load. When the
load was reduced this slipping at once
ceased and the vanes forced the full vol-
ume and made the engine pull harder.

Another pump was finally installed with
the inclosed type of runner, which is
similar to those used in multiple-stage
pumps. Although this did not entirely
eliminate the slip, a marked improvement
was noted.

Thomas H. Heath.

Seattle, Wash.

Oue.stions for Discussion

1 wish to ask a few questions and
trust all replies will be based on prac-
tical experience. They are as follows:

Will turning cold water into a red-hot
boiler cause an explosion, and if so, why ?

Will cutting two or more boilers in
together without having the pressure
equal on each boiler be liable to cause
an explosion provided that ordinary care
is used and the valve is slowly opened;
if this practice is dangerous, why?

If one boiler of a battery of several
explodes, is it liable to cause the other
boilers to explode; if so, why?

Suppose a condensing engine should
be suddenly relieved of its load and at-
tain a dangerous speed. If the throttle
valve is closed tight but the condenser
continues to operate and maintain the

Fig. I

strenpthen the cause of the isolated-plant
engineer. The wattmeter diagrams
speak for themselves and show a good
performance for a 300-''Mowatt plant.

Figuring the coal at S2.90 per ton of
2240 pounds, the coal consumption for
the day, the chart shown in Fig.
I was taken, cost about S31, that for
Fig. 2, about S34.80 and for Fig. 3, about
SS.'i. The rate of wages were, chief
engineer, S3. 14 per day; two assistant
engineers. S5. Ifi; two firemen, and one
general utility man S6. The removal of
ashes cost SI per day; oil S0.2.S; waste,
.SO. 10 and water SI. Allowing 10 per
cent, for maintenance of equipment and

Fic. 2
Three IsoLAiEn-PLANT Records

which had a 22-inch discharge and an
open-end impeller. The discharge line
varied from 200 to 1500 feet or more.
The head would never be over IS feet, but
it would vary with the tide.

Occasionally the pipe line would break
or pull apart and the engines would slow
down; why, I could never understand. It
would also labor harder on a short dis-
charge than on a long one. With a
heavy load the pressure would go up
hut little with a considerable increase in
speed.

As the line became longer the load be-
came heavier. With a heavy load the
water would slip back over the side of

Fic. 3

usual vacuum, will the engine increase

in speed after the throttle is closed; if
so, why ?

Alton, III. H. R. R(ir.K\xEiL.

Prevent Standpipe Freezing
I would like to ask some of the read-
ers of PoixHR, what is the best remedy
for preventing a standpipe from freez-
ing? It nins from a 20.000-gallon iron
tank, elevated about H) feet above the
ground and is situated in a very exposed
place. If a covering will answer, what
kind is best to use?

Thomas NrcHOLSON.
Newark, N. J.

412

POWER

September 12, 1911

Direction of Compressor
Rotation

On page 189 of the August 1 issue,
D. C R. asks if there is any particular
reason why an air compressor should run
under. The answer given is, "There is
none. In fact, the friction will be slightly
less when running over."

It seems to me that this is not quite ac-
curate for a steam-driven air compressor,
especially if the cutoff in the steam cyl-
inder occurs before half stroke. ■ Under
these conditions the flywheel is doing the
greater part of the work; therefore, it
is the same as a belt-driven machine, and
when running under the greatest stress
comes on the bottom guide. I should
think that this would produce less fric-
tion than when the top guide takes the
thrust.

L. C. Tucker.

Newburyport, Mass.

[The question and answer relate to the
compressor alone. The effect of the
angularity of the connecting rod when
running over is a tendency to lift the
crosshead from the lower guide on both
strokes, which will reduce the friction
slightly, the guide being partially relieved
of the weight of the crosshead. The fric-
tion due to the thrust of the piston rod
or to the pull of the connecting rod is
exactly the same, no m.atter which guide
takes it. — Editor.]

Filling Oil Storage Tank

In the August !5 issue, W. W. Warner
asks for information as to the best meth-
od of emptying tank cars. All oil-tank
cars have an outlet at the bottom which
will take about a 3-inch hose coupling.
One method is to run the oil by gravity
from this bottom connection, with the vent
in the dome open, as the storage tanks
were below the level of the car.

In Mr. Warner's case the tanks are
above the car so that he can connect his
discharge to the bottom outlet and run a
■H-inch air pipe to the pipe connection on
the tank dome and force the oil out by
air pressure. I have assumed that he
has compressed air as he speaks of forg-
ing furnaces.

Oil-tank cars (some of them, at least)
are equipped with heating coils so that
when the oil is very stiff in cold weather
steam can be turned on to heat the oil.
This makes it as easy to handle in winter
as in summer. Steam can be used to
force the oil out, but the condensation

Comment,

criticism, suggestions
and debate upon various
articlesjetters and edit-
orials which have ap-
peared in previous
issues

will go into the storage tank and will
have to be drained off after it settles to
the bottom.

I believe tank cars are tested to with-
stand 40 pounds pressure, but I would
not use over 10 pounds if this pressure
will do the business.

I advise him to run the steam, air and
oil pipes up to a convenient place and
use a short section of hose to connect
to the car as it may not always be left
in exactly the same spot.

Mr. Warner states that the tanks will
be 5 feet above the ground and 3 feet
above the car. If he could bring the
tanks down on the ground, below the
level of the car, he could transfer the
oil by gravity. This would be the easiest
and the cheapest way.

Fuel oil is not very thick, even in
freezing weather, and is quite easily
pumped.

I have transferred sulphuric acid
from a tank car to a storage tank at a
higher level by air pressure. Acid tanks
have two pipe connections in the dome;
one leads to within 1 inch of the bottom
of the tank, the other over the acid. The
discharge pipe is connected to the pipe
leading to the bottom of the acid and
air pressure is used to force the acid out.
Care must be taken to keep water out of
the acid, and an air pressure of over 25
pounds must not be used, as either may
cause an explosion.

There is but little danger from oil, but
I would advise as low pressure as will
do the work.

J. C. Hawkins.

Hyattsville, Md.

Replying to W. W. Warner's question
in the August 15 issue, oil may be trans-
ferred from tank cars to storage tanks by
connecting a pipe between the supply
tank and the storage tank and introduc-
ing an air pressure in the supply tank.
This is a cheap and efficient method if
compressed air is available. If not, I
suggest the following for Mr. Warner's
supply tanks:

It they are outdoors, bury them in the
ground below the freezing depth. Place
a manhole over the tanks so that they may
be accessible. A telltale should be placed
in them, and also a heating coil in the
event of low temperature. Oil m.ay be
taken from the tank by a rotary oil pump
and delivered to the forging furnaces.
This type of installation should give en-
tire satisfaction.

R. G. Cox.

.Milwaukee, Wis.

In reference to W. W. Warner's letter
in Power for August 15, I would say
that a quick and cheap way to get the
oil into his storage tanks is to connect
a hose or pipe from the discharge of his
pump to the bottom of the tank. Then
make a similar connection on top of the
tank to the storage tanks. Be sure that
the top connection is opened before the
pump is started; if there is no safety
valve on the tank an overpressure on
the tank will cause disastrous results.
The water will force the oil into the
storage tanks and the oil will always float
on top of the water. I have tried this
experiment several times and it worked
successfully.

Patrick Malloy.

New York Citv.

Silent Running Engines

The editorial in the August 8 issue
under the title, "Silent Running Engines,"
is the most comforting piece of reading
I have seen for many a day. General-
ly, when the subject of compression is
touched upon it is usually touched upon
with a 20-pound sledge; that is, you must
either have too much or none at all. Here-
tofore there has been no half-way point
at which we were allowed to run our
engines, the advocates of compression
holding that if a little is good, a lot of
it is better, so give enough to bring the
blood out of the keyways in the cranks
and flywheels. On the other hand, the
advocates of the noncompression theory
contend that if too much compression will
loosen the keys and spokes of the fly-
wheel, one should have none at all; in
fact, if it is possible to get a 30-inch vac-
umm in the cylinder at the end of the
stroke, do so. Now comes this editorial
giving all of us a grain of comfort by
telling us to have just enough. So be it.
Compression, of course, can be figured
out ver>' nicely by taking into account the

September 12, 1911

POWER

413

momentum of the moving parts just be-
fore they must be brought to rest, but I
venture to say that the quietest-running
ines in the country are those in which
right amount of compression is as-
lined in the same way as the Arkansas
cler plays the fiddle — by ear. As
- been stated, more noise is caused by
ty admission in a good many cases
1 by faulty compression. Once I
pped into an engine room where there
. a 2000-horsepower cross-compound
ine which was quite noisy on the high-
-sure side, although one could still
r the dashpot drop if he were close
ugh. I was standing at the rear of
high-pressure cylinder when an extra
i came on the engine. I could hear
piston tap the cylinder head at each
ic>ulution, so I stepped to one side and
started to go away. It had never hitherto
occurred to me why an engine should
pound more on a heavy load than on a
light load and I never ran across a man
who seemed to know. Many seemed to
be willing to risk a guess, but the guess
was usually that if the valve opened
wider on a heavy load than on a light
load the steam pressure was greater on
the piston at the point of admission. This,
of course, is all wrong, as it is only pos-
sible to get boiler pressure on a Corliss
engine, and you get that regardless of
the load.

The lead on some engines certainly has
a good deal to do with the amount of
noise they will make. It is not always
possible to have an engine run quietly at
all loads; all that can be done is to get
the best running at the load the engine
is to carry and it will not cut up very
badly at a slight over or under load.
One may indicate a half day if he will
and get about what he wants in the way
of a diagram and still have a disagree-
able pound. Simply loosen up the back
nuts on the link rod and dashpot rods,
start up, and put the normal load on the
engine. Then try a little less or a little
more until you think you have what you
want, and then shut down and tighten up
the lock nuts again.

This may not be scientific, but it does
the business and if it affects the economy
I have not yet noticed it. It is found
on a 46 and 94 by 60-inch engine running
at 75 revolutions per minute that .nbout
1/16-inch lead on the high-pressure side
is all right, and on the low-prcasure side
the steam valves set at line and line, or
with no lead, give the quietest effect. The
exhaust valves close at ."^ inches from the
end of the stroke. This engine makes
a kilowatt-hnur on 17 pounds of steam.
so I do not see any objection on that
score. The compression on the low-pres-
sure side with this setting runs up to
about 10 pounds absolute. If is very evi-
dent that if with a S.'^-inch vacuum you
could get a final compression on the
low-pressure side of 10 pounds ahsnliiic,
ir the engine should begin to exhaust to

the atmosphere the compression would
run up in proportion to the ratio between
atmospheric pressure and condenser pres-
sure, which in this case means 60 pounds
gage. It would seem, then, that if the
receiver pressure was not raised, the ex-
haust valves would necessarily become a
sort of relief valve to let the excess com-
pression back into the receiver. It does
not take much slamming due to this con-
dition to break a valve, as one weighs
1800 pounds. To avoid trouble a rig was
put on the low-pressure governor gear
so that the receiver pressure could be
immediately raised enough to hold ths
valves down on the seats.

E. H. Lane.
Kansas City, Mo.

Steam- in Cold Boiler

I have read, in the August 15 number
of Power, Leon Roundy's account of how
a boiler was tested for leaks by filling it
with cold water and then turning live
steam at 100 pounds pressure in on top
of the water. The chief in a plant where
I was working filled a vertical water-tube
boiler with cold water and started the
fire. When this was done he cut the
boiler in. Nothing happened, but I would
have preferred that this work be done
when I had a more distant view. What
did the chief think was gained by doing
this? This boiler certainly could not make
any steam until the water reached a tem-
perature which would correspond with its
pressure and in cutting it in cold it only
added a load to the other boilers for a
time, to say nothing of the evils of un-
equal expansion.

In Mr. Roundy's case, assume that the
water filled the lower half of the steam
drum and that the cold water had a tem-
perature of 60 degrees. Then the plates
below the water would have the tempera-
ture of the water, or 60 degrees. The
plates above the water were in contact
with steam of 100 pounds pressure with
a temperature of about 338 degrees.
Thus, the two parts of the drum had a
difference in temperature of

338 — 60 = 278 degrees

Sames, in his "Mechanical Engineers'
Handbook," gives the coefficient of linear
expansion of mild steel as 0.0(XXK),S7 and
the coefficient of elasticity as .if^.OOO.OOO.
Using these figures, each inch of the
plate above the water would expand

O.OOOOO.'i? --^ 278 = 0.0015846
of its length more than the same length
under the water. When expanding, the
plates will exert as much force against
anything which tends to hold them back
as would be required to stretch Ihcm the
same amount if the temperature remained
constant.

If we use the formula for the amount
of elongation of a piece under stress and
transpose it to find the stress applied, we
may find the stress necessary to stretch

the plate the amount of expansion. If
we let

P = Stress;

Z. =; Length, in this case 1 inch;

A = Area, in this case 1 square inch;

E =r Coefficient of elasticity;

X = Amount which the plate ex-
panded; we have

X A E 0.0015846 X I X 30,000,000

L ~ I ~

47.538 pounds per square inch

of section. This is the force with which
the plates above the water expand. This
strain must be taken up in the plate
along the water line.

Of course, 1 do not mean to say that
each square inch of the plate has this
strain of 47,538 pounds, for the plate
will not have a cross-section of 1 square
inch for each inch in width. If the plate
was 1 2 inch thick the cross-section would
be li square inch and the strain would
be 23,769 pounds. But the tensile strength
of the same amount of plate would only
be

55,000 -^ 2 = 27,500 pounds
The ratio of the strain due to unequal
expansion to the tensile strength would
remain the same.

If Mr. Roundy's chief filled the boiler
with water under pressure, he might have
filled it a little fuller until the air which
had been trapped in the boiler was com-
pressed to the required pressure. This
would have shown what he wished to
know. The fact that the other boiler was
running leads me to believe that the
water under pressure could be had.

L. A. FiTTS.

West Fitchburg. Mass.

Central Station \ersus Isolated
Plant

In reply to Mr. Schneider in the August
8 issue, 1 offer the following:

At my plant the boiler is but eight
years old, and shows no signs of de-
terioration, and the character of the feed
water is good. The fiues are blown with
a good blower every day and scraped
once a' week. Two gapes of water are
blown down daily and once a month the
boiler is blown off and thoroughly washed
out. It is impossible to keep a boiler any
cleaner than that one is kept. The draft
is ample, the setting is in good shape,
and ashes and combustion-chamber soot
arc not allowed to accumulate.

There are no facilities for checking up.
The only thing 1 could do was to clean
off the firing floor and fake a weighed
load from the fcain. note the time and
date firing on that lot began and when
the last was used; then divide it off into
an avcrace number of barrowlnads used
in the day to that at night. While this
is not very accurate, it is as close as it
is possible to figure. My somewhat more

414

P O W F. R

September 12, 1911

than two tons amounts to 4200 or 4300
pounds in 10 hours.

I assume that Mr. Schneider's boiler
and engine are close together. They must
be for him to be able to fire as low as
S'A pounds of coal per indicated horse-
power-hour. However, considering the
circumstances mentioned in my previous
article, I am not dissatisfied with my
showing. As for heating with exhaust
steam, nearly every plant now uses that
system (the one under discussion in-
cluded! and the really uptodate ones use
a vacuum pump in addition.

Emmet Baldv<in.

Sturbridge, Mass.

Lifting Water in Boilers

I noticed a letter by C. J. Harden, in
the August 8 issue of Power on "Lifting
Water in Boilers." I wish to take ex-
ception to his statement that "A boiler
on the line has its water in circulation
and only a part of the water is at or
very near the right temperature to flash
into steam."

It is the generally accepted theory
among engineers that practically all of
the water in the boiler is at the tem-
perature corresponding to the pressure
of the steam. This must be so when
we consider that above the water there
is a large volume of steam which would
immediately condense and give up its
latent heat and heat up any water that
happened to be near it which was at a
temperature lower than the steam itself.
Furthermore, the volume of water fed
into a boiler is so small as compared to
the total volume contained in the boiler
that the injection of this comparatively
low-temperature feed water has practical-
ly no effect in lowering the temperature
of the water in the boiler. That is. it im-
mediately mixes with the high-tempera-
ture water in the boiler and attains a
temperature corresponding to the pres-
sure.

Again, I note that Mr. Harden claims
"pressure and temperature rise quickly
and the boiler shell, not having time to
adjust itself to the new condition, lets
go." It seems highly improbable that
this could occur, inasmuch as the boiler
under discussion is directly connected to
the steam main, which, according to the
assumption in the beginning of the arti-
cle, is at a pressure lower than that in
the boiler; therefore, the boiler should
certainly equalize the pressure through
the steam pipe.

The point that I wish to bring out is
the desirability of using automatic valves
on boilers. These valves are now so
built that they serve the double pur-
pose of being automatic cutoff valves in
case of a break in the boiler or steam
line, and also of automatically cutting in
a boiler when steam pressure is being
raised. That is, when a boiler has been
cut out of service and the pressure in
it is lower than, in the steam main, this

valve will automatically close and iso-
late that boiler. Then as soon as the
steam pressure is again raised in the
idle boiler the valve will remain closed
until the pressure in the boiler being
cut in is just equal to that in the steam
main or a pound or two higher. As
soon as the latter pressure is reached the
valve opens and the new boiler is thrown
into service automatically, thus affording
safety to both the steam main and the
new boiler, and to all the other boilers
as well.

It seems strange that these valves have
not been more generally adopted in this
country. In France automatic cutoff valves
have been compulsory since 1886. when
the explosions of Eurville and Marnaval
liberated steam which killed 30 people
and seriously injured 50 others. In other
European countries such laws are now
under consideration with a prospect of
being passed at an early date. These
automatic valves are recommended by
the leading boiler-insurance companies of
this country.

F. J. McM.^HON.

New York City.

Trouble with Leaking Tubes

In reply to Mr. Reimers' letter under
the above heading in the July 18 issue. I
have this to say: I have charge of a
two-sheet, double-riveted lap-seam re-
turn-tubular boiler that has been in use
13 years. It has never developed a leak-
ing tube yet, and the tubes are in per-
fect condition. This boiler has no rods
through it below the tube line, as de-
scribed by Mr. Reimers.

Why is it that the boiler inspectors tell
us that a two-sheet boiler is a poor thing?
C. J. Wright.

.Mliance. O.

Riverton Turbine Accident

The account of the Riverton turbine ac-
cident in the issue of August 8 is inter-
esting.

The theory advanced that the machine
was running above norma! speed seems
the most tenable, and will, no doubt,
stand until tangible proof is brought for-
ward to the contrary.

.^t half speed or even full speed, with
such rugged construction and generous
factor of safety, there is hardly a pos-
sibility of a machine going to pieces, in
the manner described.

It is inconceivable that a chisel or nut
could have caused the disaster, as trouble
from either one would have been ob-
served at the moment of starting. Fur-
thermore, as the stock of a chisel is M
inch or more and the assp-nMing nuts
are either I'i- or Pj-inch bolt size,
the small space between the bottom of
the diaphragm and the top of bucket
wheel would not permit the insertion of a
chisel, much less a nut. Foreign sub-
stances in the intermediate holders would

be out of the question also, as the parts
could not have been assembled at all.

Again, any obstruction in the turbine
sufficient to cause the accident would
have made itself known on starting by a
fiuctuation in the step pressure, by vibra-
tion and by excessive first-stage pressure.

If the bucket wheels were rubbing, due
to too high or too low a step screw, it
would, if run long enough, wreck the
internal parts of the machine, but would
not cause such an accident as that at
Riverton. If the machine were running
at half or even at full speed, it would
slow down first.

If tools or machine parts had been
left in the turbine they would have been
missed, so the obstruction theory might
as well be dismissed.

It is not at all likely that a machine
would run for 10 minutes, as stated, with
the throttle cracked and remain at the
same speed; it would most likely in-
crease in speed. Judging by the meager
particulars at hand, we would not be far
out of the way in accepting the theory
that the turbine was above its normal
speed; that the governor failed to close
the valves or that the valves were im-
properly set; that the emergency gov-
ernor failed to work or, having worked,
the throttle failed to close. The latter
is quite possible in certain types of throt-
tle valve if they are in other than their
wide or nearly wide-open position.

That the buckets show signs of hav-
ing rubbed does not necessarily mean
that they were obstructed or that they
were not central on starting up. A hot
bearing or tight carbon packing would
cause rubbing, or, more likely, a high
speed would bring the greatest pull on
the bucket segments along the line of the
center of gravity, starting the rivets and
causing the segments to turn upward or
downward as the case might be.

It is not my intention to pass judgment
but rather to share my limited experi-
ence with others.

C. A. Blue.

Boston. Mass.

Locating Keyway in Corliss
^'^alve Stems

S. Kirlin, writing under the above nead-
ing in the August 1 issue, explains his
way of determining the proper position
for the keyway in new valve stems.

I think it is better to lay the old stems
on a good faceplate and locate the posi-
tion of the keyway. Then it is an easy
matter to mark the new stems. If the old
stems are incorrect the proper posi-
tion should be located and marked before
the stems are removed. Then the pro-
cedure is as before, except that the gage
will be set on the old stem to the proper
position rather than to the actual posi-
tion of the keyway.

I was interested in his tables, showing
various sizes of lap for steam valves.

September 12, 191 1

POWER

415

They may do when starting, but most
likely the indicator will point out many
defects that can be overcome that will
change the lap. and the opening of the
exhaust.

L. Johnson.
Exeter. N. H.

Centrifugal Pump.s, Their De-
sign and Construction

In the August 1 issue of Power, on
page 195, was published a review of the
book "Centrifugal Pumps, Their Design
and Construction," by L. C. Loewenstein
and C. P. Crissey, which I consider so
far fails to do the work justice that 1 re-
quest the publication of my views, in the
hope that it may do justice to what I feel
sure is the best technical book on cen-
trifugal pumps. I believe I can speak
with some authority on the subject as I
have been identified with centrifugal-
pump design for over 20 years and de-
signed for Sulzer Brothers, of Switzer-
land, some of the very earliest high-
pressure centrifugal pumps the success
of which really led to the introduction
of this type of pump in Europe. Since
then I have been identified with several
of the most prominent pump builders of
England as chief designer and chief en-
gineer.

The reviewer states that "The theory
expounded in this book is totally unsuited
to the present needs of the pump de-
signer." This is absolutely incorrect;
this theory is recognized by the vast
majority of pump designers as best
suited to their work. It is not suited to
any designer who does not believe in the
efficiency of diffuser vanes.

The reviewer criticizes the solution of
the problem on page 126 but does not
state how he would treat the same ex-
ample. There are, of course, two ways
of building pumps; the one he suggests:
"A stock of standard (?) pump-casing
patterns, each capable of accommodating
a limited series of pump diameters, and
for each proposition make a special im-
peller," as a result of which "Eventually
the manufacturer accumulates a stock of
impeller patterns whose characteristics
have been well tested and which arc
classified." The other way, as outlined
in the book, is the more scientific one
and also the more economical way; that
is, to build the pump impellers with pre-
determined characteristics and predeter-
mined classification so that the range of
possible service of each pattern is well
known in advance of actual construction,
permitting the designer to cover the pos-
sible range of usefulness of each de-
sign most economically.

The reviewer states: "The authors be-
lieve strongly in the efficiency of guide
vanes surrounding the periphery of the
impeller"; and intimates that centrifugal
pumps without guide vanes are prefer-
able. In fact, he quotes the authors as

agreeing to his views when they state on
page 83: "By exact and very careful
construction, pumps without guide vanes
can be made to give fairly satisfactory
efficiencies."

The reviewer also tries to prove his
point by referring to Fig. 267. which
shows a five-stage turbine-driven pump
without diffuser vanes which gave at the
official tests an efficiency of 58 per cent.
The best answer to his views is the fact
that of about 30 of the most prominent
manufacturers of centrifugal pumps, all
described in the book, only one, or pos-
sibly two, do not use diffuser vanes,
whereas all the others do use them. In
fact, the reviewer states that this portion
of the book "is exceedingly interesting
and gives a very good idea of the pres-
ent state of the art both in Europe and in
this country." If this is true, the present
state of the art surely shows most con-
clusively that diffuser vanes are con-
sidered preferable for high-pressure cen-
trifugal pumps and that almost all de-
signers agree with the authors as to their
efficiency. Hence, although the book ex-
pounds a theory totally unsuited to the
needs of those few designers who do not
use diffuser vanes, the large majority
of designers, engineers and students will
find the book admirably adapted to their
needs.

One of the best features of the book,
and to me the most valuable, was not
mentioned. The book is worth its pub-
lication if for no other reason than the
most thorough and excellent presenta-
tion of the theory and calculation of
critical speeds and the strengths of im-
pellers. The question of critical speed
is of vital importance to designers of
high-speed machinery, and until the pub-
lication of this book no easy method of
computation had ever been published. The
theory has been given in an abstract
manner by others, but no presentation
has ever been so clear and useful as the
one given by the authors of this book.

In my opinion, which I am sure is
shared by many others, the book is by
far the best presentation of the theory
and practice of centrifugal-pump design
ever published.

Hugo Y. Angstrom.
Manchester, England.

Sizes of Turbine Steam and
pA'hau.st Pipes

W. J. A. London, in the July 25 issue,
refers to some criticisms of Mr. Neilson,
and in return criticizes Mr. Neilson's
formula from a practical point of view.

In support of Mr. Neilson I would
say that I have had considerable experi-
ence in designing exhaust pipes and
passages based on his formula, and have
found it quite simple to use and per-
fectly satisfactory in practice. In fact,
the curves published in Power for July

13, 1909, over my name, are based on
his formula.

Mr. London refers to sharp bends in
pipe lines, but it is obvious that the
number of these appearing in a proper-
ly designed system would be so small
as to have practically no serious defect.
W. Vincent Treeby.

Goodmayer. Essex, England.

Central Station Methods

The following, which is the substance
of an advertisement which appeared in
the daily papers in a certain city, is
typical of the distorted and exaggerated
statements constantly being made to the
public:

"Another Large Private Plant Displaced
by Central Station Power.
"After the most searching investiga-
tions and thorough practical tests the

Hotel has abandoned its generating

equipment and contracted for our power.
"This is a most notable demonstration
of the superiority of central-station ser-
vice as this isolated plant was one of the

largest and most efficient in .

"It furnished light and power for the
hotel; the and Auditorium the-
aters; Turkish baths and rathskeller.
The installation comprises over 100
horsepower in motors; 6753 incandescent
lamps, 5 large electric signs and 8
flaming arcs.

"Here are some of the advantages de-
rived from the new power source: A
distinct monetary saving, better light, less
vibration, less noise, elimination of the
excessive heat from the boilers, no dirt,
ashes or smoke and the hotel will be
from 5 to 15 degrees cooler during the
summer than heretofore.

"Our industrial power department will
make an investigation of your plant and
submit comparative figures for your in-
spection. It may be the means of saving
you a great deal of annoyance and money.
Get in touch with us today.

"The Gas and Electric Company."
Here is what the plant actually con-
tained:

Poorly arranged boilers in a room not
properly ventilated. A large ventilating
fan driven by a piston-valve throttling
engine which had no jacketing and which
had been allowed to run for probably
eight years without any overhauling. An
ammonia compressor driven by a com-
mon throttling engine without jacketing.
A common steam pump with cylinders
but poorly jacketed, doing duty as an
elevator pump. Four dvnamns driven by
balanced plug-valve engines which leaked
steam at a scandalous rate.

With such an equipment it is not diffi-
cult for the central station to displace
the plant. But the story would be far
different had the plant been rightly laid
out in the beginning.

C. R. McGahey.
Baltimore, Md.

416

POWER

September 12, 1911

^_ '

Safety Vul-ve Spring Formulas
Will you explain why I cannot make
the accompanying statements and for-
mulas for safety-valve springs agree?

The size of steel for safety-valve
springs may be found by the following
formula :

'^-

: = d

\s X D

c

where

s = Load on the spring in pounds;
B = Diameter of the spring in inches
from center to center of the
wire ;
d;= Diameter or side of square of

the wire in inches;
C = 8000 for round and 11,000 for
square steel.
The pressure or load on a safety valve
due to the spring may be found by the
following formula:

d^ X 2_ (,
~~D -^

where

d = Diameter of the wire in six-
teenths of an inch;
D= Diameter of the spring in inches
from center to center of the
wire ;
S = Load on the spring in pounds.
H. D. M.
The formulas are practically identical.
The first can be expressed more simply

as

Sx D

-.d^

8ooo

In this formula d is the diameter of the
wire in inches. In the second, the same
letter represents the diameter of the
wire in sixteenths of an inch. The ex-
pression for the same quantity will there-
fore be 16 times as large in the second
case as in the first and becomes

(16 dr

Both sides of the equation are practically

multiplied by 16" and it becomes

S X D X 16^ -, ,,

^i6' a'

• 8ooo

But 16= is 4096, and substituted for
the 16° in the formula it will be seen
that it will go into the 8000 in the de-
nominator very nearly two times, making
it read:

SX Dy 4096

8000

•= l6M3

Transposing for S it takes the form
i6^

= S

_d^ X 2

D
which is the second formula, the 16'

Questions arc^

not answered unless

accompanied by thcj

name and address of the

inquirer. This page is

for you when stuck-

use it

the numerator being implied by the fact
that d is given in sixteenths of an inch
and that these are cubed. If the example
is worked out by the two rules, it will
come out with only the slight difference
due to the failure of 4096 to divide ex-
actly into 8000.

Cutoff Slide Valve Engine

How early in the stroke can a slide
valve be made to cut off?

L. L. S.

Five-eighths of the stroke is as early
as it is practicable to cut off in a slide-
valve engine, though any cutoff desired
may be had by adding lap to the valve,
but it is impossible to get a full port
opening with a cutoff earlier than half
stroke.

Horsepo-d;er of Fej-tical Boiler

What is the heating surface in a ver-
tical fire-tube boiler, and what is the
horsepower of a vertical boiler with a
40-inch firebox 26 inches high and with
forty-two lj<5-inch tubes 66 inches long?
The water line is 50 inches above the
crown sheet.

H. P. B.

The heating surface of a boiler is all
of that surface which is exposed to heat
upon one side and water upon the
other.

In a vertical boiler this surface con-
sists of the inside area of all of the
tubes from the crown sheet to the water
line; the area of the side sheet of the
firebox and the area of the crown sheet
minus the cross-sectional area of all the
tubes.

It takes 2.87 feet of a 1 '4 -inch tube
to make 1 square foot of area, and in 42
tubes submerged 50 inches or 4.166 feet
the heating surface is
4.1G6 X 4:

;.87

^ ^ 60.9 square feet

The diameter of the firebox is 40 inches
by 26 inches high and has an area of
40 X :,.i4i6 X 26

J 44

: 22.68 square feet

The inside area of forty-two lj.<-inch
tubes is

42 X 1.39 = 58.38 square inches
The heating surface of the 40-inch
crown is

(40 X 40 X 0.7854) — 58-38 _
M4
8.32 square feet

Allowing 10 square feet of heating sur-
face for horsepower, the rating of the
boiler is

60,9 + 22.68 -I- 8.32. ,

^ =9.19 norsepouer

Graphite in Boilers

I have been told that graphite will
prevent scale from forming in a boiler.
Will its use hurt the boiler? Will the
steam be so affected that it cannot be
used for brewing?

A. J. L.

Graphite will not affect a boiler pre-
judicially. It is sometimes applied in the
form of paint on the inside of boilers to
prevent the adhesion of scale to the sur-
face. The steam from such boilers may
be used for brewing purposes provided
that the boiler does not foam or prime,
as in such cases water will be carried
over v/ith the steam, and if it contains
suspended graphite or other matter it
will not be suitable for brewing.

Heating Surface and Boiler
Horsepoiver

How are the heating surface and horse-
power of horizontal return-tubular boil-
ers found?

J. F. M.

To find the heating surface of a re-
turn-tubular boiler add together the area
of one-half of the shell, the area of all
the tubes and the area of one head.
From this sum subtract twice the area of
one end of all the tubes. The remainder
will be the heating surface.

For example, the heating surface of a
boiler 66 inches by 17 feet with 70 four-
inch tubes is

i shell II6.S6 square feet

.-^cvciitvl-in.tlv 17-ft. tubes. 1166.66 square feet

One head." 23.76 square feet

Makiim a total of 1337.2S square feet

From this subtract the area

of 1 40 4-in. tube ends 12.20 square feet

The remainder will be 1325.0S square feet

Ten square feet of heating surface is
the standard allowance for a boiler horse-
power.

132S.08 , . „

-^i— ^ = 132.5 hoTsepower

September 12. 1911

POWER

Issued Weekly by the

Hill Publishing Company

Jobs A. Hill, Pits, and Treas. Rob't 3IcKkas,S€c"j-.

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Entered as second class matter, De-
cember 20, 1910. at the posit oflice at
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( IRCVLA TIOX HTJ. Timr.yT

Of tlii« iDSUC .11.000 coiiien arc printed.

Xone sent frrc regularly, no returns from
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arc tire, net circulation.

Contents

Ihjvelopmcnts in I'rimo Movers

Steam En;j:ine I-ut)ricatlnti

Kemovlnz Emulsllied Oil from Water....

Turbines for .Tap.inc,«e Navy

Special Crane for Coal

A Illph Speed Cast Iron Flywheel

Why .Ilmmy wa.s Refused a License

"it Transmission In Boilers

■den vs. Steel Boilers

"•den KnockolT Plate

<ias Knglne Cycles

A Had Wreck from a Small Cause

Practical I'nlnls on Electric WlrlnR

Prorllral l.i'tlcrs :

lyllnrter oil for Hot Bearings

Turlilne flllInK Trouble. . . .('ondeinns
License Ijiw. . . .StraiRblenlnR a Con-
necting Rod Belt Ran to Side of

Pulley .... Improved Stop Vnlve....

Knily 1x>K ShP<t No Relief Vnlve

on Heater., .laiilnnd Plant Prac-
llre.....\ i'iiiii|i i;i;|icrlence Ques-
tions fur l'i"ins«lon .... Prevent

Stundplpc I"rcc7,luK 40!l

' i|»«lon letters:
PlriTiion of f'omppes'ir Hotntinn

iTi:

i'lM

l.ilfliii; Water

In ilnllrrs Trouble with l,<>nklnR

TiilM-« . . Rlrerlon Tiirbln(> Aoolrtent
J i tine Kevway In Corliss
^ -. . . .f'entrlfntnl Pumps,

I i- '. 1' l.n dnd Construction. .. .
Slr<-« m riirhinn Sirnm and Ex-
haust Pipe* .... Central 8 t n t I o n

Mplhndii ■im-41."i

•''Tlals 417m

•nnmlcs of ltnt-wati>r Heatlnic 4Ui

Sudden Release of Pressure

A correspondent is doubtful as to what
effect a sudden release of steam and
water under high pressure will have on
a steair boiler. Although this question
has been settled by the majority of engi-
neers, there are some who feel convinced
that there is but slight danger from such
an occurrence.

There is extreme danger from a sudden
release of steam, and water either from
a return-tubular boiler or a water-tube
boiler. When the shell of a return-tubular
boiler ruptures it is destroyed by the
sudden release of the energy contained
in all of the water and steam confined
within. The same thing happens when
the steam drum of a water-tube boiler
ruptures as it contains large quantities
of water and steam.

Even the bursting of a steam header
may cause an explosion. No better il-
lustration can be cited than the St. Louis
explosion, several years ago, when six
out of seven water-tube boilers exploded
in rapid succession from this cause.

Explosions of this nature are made
possible as, although the headers or drum
do not contain large volumes of steam,
they are connected with tubes which con-
tain enough water and steam under high
pressure to blow the boiler to pieces
when an initial rupture occurs.

Constant contact with danger makes
men careless; they take a chance here
and a chance there and are lulled into a
sense of security because an accident has
never happened to them before. It may
be known that a steam header is weak,
but these men take a chance that it will
hold and nothing is done.

Often the engineer realizes the chances
that are taken but he is powerless to
have the matter remedied, as is Instanced
in the case of a certain steam plant in-
stalled in an office building about four-
teen years ago and in operation today.
Water-tube boilers arc used and a steam
pressure of one hundred and fifty-five
pounds per square inch Is carried on the
boilers and the steam mains. These mains
arc constructed of standard pipe and fit-
tings, whereas they should be of extra-
heavy inaterial.

The chief engineer bns always been
fearful of these ripts and fittings, es-
pecially the latter, but he cannot persuade
the manager of the building to install a
heavy system.

These pipe lines may continue in ser-
vice indefinitely or Ihcy may be respon-

sible for a boiler explosion at any
moment. Thus a chance is being taken,
lives are imperiled, and all for the pur-
pose of saving a few dollars.

It is the duty of every engineer to
remedy any weakness known to exist in
his plant if it is in his power to do so.
The bursting of a steam header may re-
sult in nothing more than lost steam, and
there is grave danger that it may cause a,
boiler explosion and loss of life.

The Institute of Operating
Engineers

The organization of the Institute is an
accomplished fact. The first convention
has been held and articles of Incorpors-
tion taken out. For an organization which
has, as yet, few local branches and of
which few of the members are so situated
as to be able to attend a meeting in a
distant city at their own expense, the at-
tendance was good, and the interest and
enthusiasm Inspiring.

A half day sufficed for all the business,
including the election of officers, and the
remainder of the time was devoted to
the presentation and discussion of pro-
fessional and technical papers. Some of
the older societies, which spend the
greater part of a week electing a couple
of officers, might take a leaf from the
new Institute's book in this respect.

Permanent headquarters will be main-
tained at the Engineering Societies build-
ing in New York and engineers, especial-
ly those who can qualify as master op-
erating engineers, are invited and urged
to connect themselves with it directly.

In the meantime, efforts will be di-
rected at the organization of branches
which shall organize local facilities for
carrying out courses of instruction en-
abling the members to meet the require-
inenis of the Institute for the various
grades.

The Institute offers the best means yet
proposed for a man who must work out
his own education and destiny to do so
under competent guidance, with the in-
centive of the fellowship of co-workers
in the same lines and with the assurance
of recognition of such work as he shall
accomplish and such merit as he shall de-
velop. An Inquiry addressed to the secre-
tary of the Institute of Operating En-
gineers, Engineering Societies building,
29 West Thirty-ninth street. New York,
will bring full particulars.

POWER

September 12, 1911

Pulleys and Belting

It is often loosely said, when speaking
of the behavior of belting, that "a belt
will always run to the high side of the
pulley." Without concise definition the
term "high side" is a meaningless ex-
pression. A belt running over a pulley
will always tend to move laterally toward
that portion of the pulley face with which
it first comes in contact, regardless of
the contour of the face of the pulley, its
alinement or that of the shaft. It is the
direction of the belt going onto the
pulley that decides how it will run and
not the direction in which it leaves.
Shafts are parallel when their center
lines are the same distance apart through-
out their length. Pulleys on parallel
shafts are in line when a line joining the
middle of their faces is square with the
shafts, and when on shafts not in the
same plane they are in line if a line from
the middle of the face of the pulley where
the belt leaves falls on the middle of
the face of the receiving pulley at right
angles with its axis. Both pulleys and
shafts may be so far out of line as to
wholly overcome the tendency of the belt
to move toward the portion of the pulley
first touched, but this fact does not de-
stroy the tendency. It overcomes it.

If a pulley has a crowned face, the
middle of the crown is the portion first
to come in contact with the belt and it
will tend to keep it running on
the middle of the pulley face, which
is in this case the high side. Where
it has a straight face and is much
wider than the belt, the belt will run
equally well on any part of the pulley
face if the shaft is in line. If the shaft
is out of line, that portion of the pulley
rim which is furthest from the other shaft
is the high side, but the belt will run
away from this side toward the other or
low side because the first contact is on
this portion of the pulley face and the
belt must move toward it.

It will not require a great deal of
study on the part of anyone to get a
thorough understanding of the governing
principles in this matter as the behavior
of a belt running onto a pulley is identical
with that of a beam moving on rolls.

If the beam is square with the rolls it
will move only in the direction of its
length. If, however, one of the rolls is
at an angle with the beam it will in
turning move sidewise as well as forward
and the lateral movement will be toward
the end of the roll where the first contact
comes and which, if the roll were a pul-
ley and the beam a belt, would be the
low side.

It is the direction in which the belt
goes onto the pulley that determines its
behavior. The direction of leaving is a
matter of no consequence whatever. It
is this that makes the running of crossed,
quarter-turn and any angle belts possible.

So long as a belt goes onto a pulley at
right angles to its axis it will run satis-
factorily, regardless of high or low sides.

Oil in Boilers

When the boiler-feed water is taken
from the hotwell of a jet condenser, as is
commonly the practice where fresh water
is available for condensing purposes,
there is little danger that excessive quan-
tities of oil will be carried to the boiler.
There is believed to be little danger to
any type of boiler from the oil itself
because, being lighter than the water, it
will not sink to the bottom and become
attached to the plates. The error in this
belief lies in the assumption that what is
oil when it enters the boiler remains oil.
It does not. Subjected to the long con-
tinued high temperature of the water, it
is slowly distilled, that portion which is
volatilized going off with the steam, leav-
ing behind a residue of a higher specific
gravity than water, which sinks to the
bottom as soon as the circulation stops.
When cold it is firm and nonadhesive. but
when heated is not unlike asphaltum.

So long as the circulation continues,
this matter will travel along with the cur-
rent and do no harm. When it settles
on the comparatively warm sheet it ad-
heres to it so strongly that it is not dis-
lodged when the circulation starts again.
Water is kept from contact with the
sheet and a "bag" is the result.

When a bag is caused by oil it is liable
to be anywhere on the shell below the
fire line. It is usually near the bottom,
but may be well up on the side and any-
where between the front and rear heads.

The mass that clings to the sheet is not
always entirely oil residual. It is often
found agglomerated w'ith the scale-mak-
ing solids of the water in irregular
masses in all parts of the boiler.

What is really more dangerous, be-
cause less liable to be suspected, is the
milky-colored emulsion which goes to the
boiler after the heavier-bodied oil has
been removed by filtration. This does
not behave like oil proper in associating
with foreign matter nor by gathering in
large or small masses, but goes atom by
atom to the shell of the boiler, which it
covers with a tissue of hard, bright, black
varnish, which as effectually prevents the
contact of water as the thickest coat of
scale. It covers the entire sheet below
the fire line before it is noticed and the
"bag" is often as wide as the diameter
of the boiler and as long as the sheet.
This bagging is gradual, as at the first
slight stretch the varnish cracks and the
water cools the softened sheet and re-
stores its strength until the coat of var-
nish again covers it; the operation is re-
peated until the sheets are bulged like a
barrel. Neither the bulging nor the bag-
ging can be avoided without completely
removing the oil and its emulsion from
the water.

Clean, or Pretty Clean?

Are your boilers really clean, or do
you only think that they are? This
thought is suggested by the inside history
which we have just learned of the placing
of a tube cleaner.

The cleaner was one of the "knocker"
type and the boilers were horizontal
tubulars. The manager of the plant was
not at all convinced of his need for such
an apparatus. The water was first-class,
they cleaned out frequently, the boiler in-
spector complimented them on the ex-
cellent condition of their boilers and
there seemed fo be but little chance that
they would buy a cleaner, but the man-
ager consented to let the salesman send
one on trial, to be kept and paid for only
if it proved so satisfactory that he really
thought they wanted it.

The cleaner was sent and tried, but it
removed no scale; instead, it disclosed
considerable "crust" on the inside or fire
side of the tubes. The manager and his
engineer then concluded that what they
wanted was a soot and crust remover.
There was, he said, practically no scale
in the boiler except at the back ends of
the tubes, and this the engineer pre-
ferred to remove with a hammer or chain.
The manufacturer of the cleaner
pleaded for a fair trial as the cleaner
depended upon the vibration set up in
the tube to free the scale and it could
not get up this vibration when pounding
upon a cushion of soot. He pointed out
that by the use of the head provided for
that purpose the apparatus itself would
clean the inside of the tube, and then
by the substitution of the hammer head
it would knock the scale off from the
outside. The manager consented to al-
low the cleaner to remain until another
opportunity offered to try it. When it
came he wrote that after thoroughly
cleaning the tubes of soot the cleaner had
been put through two boilers, and over
four hundred pounds of scale were taken
out, some of which was more than a
quarter of an inch in thickness. The
boilers had been washed out thoroughly
twice a month, the visible surfaces ap-
peared to be clean, and they were amazed
to find that there was any scale to speak
of.

It appears that this is not an uncom-
mon experience. A boiler is "pretty
clean"; it keeps on steaming all right,
the inspector is satisfied and nothing
more is done about it, whereas a good,
thorough cleaning will reveal unsuspected
accumulations, improve the efficiency and
prolong the life of the boiler.

On August 24, a cylinder head blew
out at the Greylock Woolen Alills, North
Adams, Alass. It is reported that the en-
gineer was badly injured and a number
of the workers hurt. It is also stated that
the building was badly damaged.

September 12. 1911

POWER

Economics of Hot Water
Heating*

By Ira N. Evans!

The following article is intended to
give some actual results in the form of
curves and tables from a plant installed
as described in the July 18 number, and
also a method of getting at the coa! con-
sumption and the cost of exhaust heating
applicable to any plant.

Most owners and manufacturers can
tell to a small fraction the amount of
fuel required for power and will spend
large sums to compound or condense
an engine for a comparatively small sav-
ing. But when it comes to the heating
system no records are kept, and they
know little or nothing as to the actual
fuel cost of operation. They generally
assume that if they are utilizing the ex-
haust steam the heating costs nothing.
When it is decided to extend a plant or
build a new one the engines and boilers
are purchased first without reference to

.MrJrap

Supply Thermo

L, me. , — ^ J,
J±Buildmqs^\ 3 ill

f ' ^ J^^'-"^'

\ To Boilers , frpr-- r— 1 f- V-^

excessive amount and the heating ap-
paratus is then made uneconomical in
utilizing this steam because there is a
surplus, notwithstanding the fact that the
heating system is only operated seven
months in the year. This, of course,
would not be acknowledged in any par-
ticular case but instances have occurred
where this is the final result.

The diagram. Fig. 1, from the previous
article and reproduced herewith, shows a
plant arrangement for a hot-water heat-
ing system using forced circulation, which
does not interfere with the arrangement
or the operation of the condenser and

colder the condensing capacity of the
heating system increases in proportion
to the decreased vacuum and increased
steam consumption on the turbine.

Fig. 2 shows the curves of operation
of the plant of the Lackawanna railroad
at its Hoboken terminal, arranged sub-
stantially as shown in Fig. 1. These
curves were obtained by keeping a log
to determine the requirements of water
temperatures for satisfactory heating, and
the plant is at present operated accord-
ing to this schedule. In this plant there
are about 70,000 square feet of radia-
tion and the water circuit is about a
mile in length.

There are several buildings. The
power plant, centrally located at the end
of the train shed, consists of about
3000 horsepower in boilers, two large
compound Ingersoll-Sergeant air com-
pressors for furnishing air for the sig-
nals and switching system in the yard
as well as the air pressure needed to
adjust the water level in the expansion
tank 7" of the heating system. The amount

Separate Returns

Hot -Well Pumps

Fic. 1. Diagram of Connections of Hot-water Heating System

the method of heating or probable heat-
ing load beyond the maximum require-
ments in zero weather. Later, the heat-
ing plant is modified to meet cuts in the
original appropriation.

The type of heating system, especially
if hot water is under consideration,
should be just as much a factor in de-
termining the size and type of engine
and the arrangement of the plant as are
the power load and physical location.

In many cases where it is proposed to
use exhaust steam for heating, the plant
is actually so arranged as to furnish an

•ropyrUhlKl. 1!in. Iiy Ira N. Kvnn«
ifVinmiltlne fnirlnfpr. tir>fttlnff nnd power,
l.V. KroRilwajr. New York CItjr.

engine at any time and yet the heating
system utilizes the exhaust steam from
the turbine under partial vacuum.

By this arrangement the heating sys-
tem reduces the work on the regular
condenser by performing its function to
the extent only of the actual steam re-
quirements for heating at any given out-
side temperature condition.

The system will condense all the steam
at any vacuum regardless of the varia-
tion in the engine load, and the tempera-
ture of the water in the heating sys-
tem can be varied at will to meet outside
weather conditions by changing the vac-
uum. With a constant temperature in
the space heated, as the weather grows

of water and air in this tank are regu-
lated in conjunction with the differential
gages which show the static head on the
system. The tank is kept about 25 per
cent, full of water, the air pressure be-
ing used to lower the level of water in
the tank by forcing it into the system.
An automatic air trap releases the dis-
placed air at the top of the system by
opening when no water is present and
closing when the water raises the float.
There are two Wcslinghousc- Parsons
turbines of .°>0n kilowatts capacity each
for furnishing light and power in the
buildings. The power for operating the
motor pump on the heating system is
taken from cither of these turbines. The

420

P0\)7ER

September 12. 1911

economizer is not connected to the heat-
ing system as the plant operates 24 hours
a day and the waste heat from the gases
is always economically utilized for feed
purposes.

The plant is operated condensing, tak-
ing water from the North river, and
the heaters and pumps for the hot-water
heating system are so arranged as to
utilize the exhaust steam under partial
vacuum from either machine, as either

Temperatures of Water

.„ 100 130 MO 160 _i8o _m 2?0_,„

I I I I I I Vsf i I "

I TTnr\| i

II MM \\~rT~
— n — A\ \

Fig. 2. Temperature-v.acuum Curves

turbine may be operated on either con-
denser with full vacuum by manipulating
the floor-stand valves without stopping
the units.

As may be seen in Fig. 1, pressure
gages on either side of the pumps show
by their difference in reading the pounds
pressure of friction head against which
the pu.Tip is operating, and thus indicate
the rapidity of circulation. The thermom-
eter on the steam chamber of the ex-
haust heater shows the temperature of
the reduced vacuum required for any
given water temperatures indicated by
the thermometejs on the return header
and supply main. The difference in read-
ings of these two thermometers is the .
drop in temperature or the number of
degrees absorbed in the heaters and ex-
tracted by the radiation. On this par-
ticular job, recording instruments are
used throughout and charts are inspected
daily by the chief for any unusual de-
velopments.

Curves R and S, Fig. 2, give the read-
ings of the supply and return thermom-
eters plotted as abscissas with the corre-
sponding outside temperature as ordi-
nates. Curve V, shows the theoretical
vacuum in inches and pounds as or-
dinates corresponding to the supply tem-
perature as abscissa. Curve V is the
actual vacuum indicated by the thermom-
eter on the exhaust heater with the read-
ings plotted as ordinates and the cor-
responding supply-water temperatures
as abscissas.

By following the outside temperature
lines to their intersection with the curves
R and S, the corresponding return and
supply-water temperatures are found,
and by following the water-temperature
lines to their intersection with Vi and V,
the theoretical and actual vacuum can
be read from the corresponding figures
on the right side of the chart. When
the weather becomes cold the vacuum
curve is steep and a slight increase in
water temperature requires a correspond-
ingly greater decrease in vacuum or in-
crease in back pressure.

The shape of the cur\'es R and S de-
pend entirely on the amount of direct
radiation and air supply; indirect heat-
ing may require a higher temperature
of water in extreme weather and a cor-
respondingly lower vacuum.

The amount of water circulated is
found to be nearly constant for a given
speed of the pump and was obtained by
a recording instrument on a venturi meter

In extreme weather, due to the rapid
decrease in vacuum, the advantages of
connecting the circulating pumps in
series and operating both become ap-
parent as the increased circulation re-
duces the drop and the average water
temperature, causing greater efficiency
of transmission in the heaters and radia-
tion and reducing steam consumption.

Table 1 gives the data from which
Fig. 3 was plotted. The supply and re-
turn temperatures with corresponding
vacuums were taken from Fig. 2 for each
5-degree interval of outside temperature.
The vacuum in each case is the maxi-
mum that can be carried to give the
proper water temperature to heat the
spaces properly for any outside corre-
sponding temperature.

Curve H is obtained by plotting the
pounds of steam per hour given under
H in the table with the corresponding
outside temperature.

Curve T shows the amount of exhaust

Outside Temperature
20 25 30 35 40 45

20,000

I I Outside Temperature |"

182.5 177 , 171 165 ! 158.5 1 150 | 159 1265

Return Temperature
194.5 188.3 181.6 1 174.9 [ 167.8 ; 158.5 j 146.6 133

Supply ITemp'eratJre
6.4 I 9 I 11.5 I 14 I 17 1 19.5 | 22 124.2
Vacuum, Inches

Fig. 3. Curves Showing Relation between Stea.m Consumption of Turbine
AND Engine and the Requirements of Hot-water Heating Syste.m

placed" in the water circuit. The amount
at present is 3,350,000 gallons in 24
hours or 1,158,700 pounds per hour. The
amount of water and the speed of the
pump are not varied, the reduction in
heat transmission being accomplished
entirely by changing the temperature of
the circulating water and varying the vac-
uum. This mistake of van,'ing the water
circulation and causing a higher average
water temperature has been made in
a number of cases.

steam available under different vacuums
with a constant load of 400 kilowatts at
the switchboard. The different rates are
given in Table 1 under the proper head-
ing and total number of pounds of steam
is found by multiplying by 400. These
values are given under the heading
"Cur\'e V,' and are plotted in conjunc-
tion with the corresponding vacuums and
outside temperatures.

Curve R is the steam consumption of
a 650-horsepower compound-condensing

September 12, 1911

POWER

421

engine with 100 per cent, load and is
assumed as the nearest reciprocating
unit in order that its results may be com-
pared with the turbine. The rate and
total steam consumption under the dif-
ferent vacuums are given in Table 1.
Line H', Fig. 3, indicates the steam con-
sumption of a heating system with the
medium at 210 degrees and with all heat-
ing surface turned on. Line T" is the
steam consumption per hour of the tur-
bine with 400 kilowatts load and slight
back pressure. Line T' represents the
steam consumption with the turbine un-
der 28 inches of vacuum. Line R' is the
steam consumption of the reciprocating
engine with 400 kilowatts load at the
switchboard and a vacuum of 26 inches.
R" indicates the steam consumption of
the reciprocating engine with a load
of 400 kilowatts at the switchboard, or
650 indicated horsepower, under a slight
back pressure. By subtracting the pounds
of steam available at a vacuum of 28

Fig. 3, it may be noticed that ttie line
goes below the requirements of the tur-
bine on full vacuum, or curve T', and
the actual cost T — T' is only 960 pounds.

The cost of operating the reciprocating
engine is not worked out in detail, but
it can readily be judged from the curves.
The curve of steam consumption under
different vacuums does not coincide at
all with curve H. The engine would
operate at no vacuum until R" crosses H
at 25 degrees outside temperature and
there would be only about two changes
in vacuum available between 25 and 60
degrees outside temperature, or full vac-
uum. All periods colder than 25 de-
grees would require the addition of live
steam or another unit operated noncon-
densing. In the latter case the friction
load and losses of the additional machine
would nearly cancel any saving over
using live steam.

The large reciprocating engine does
not lend itself readily either to wide

vacuum will be greater than that of the
turbine. In this case it would be
9100 — 8240 = 860 pounds per hour
The steam consumption on the reciprocat-
ing engine increases with both reduction
and increase of load on the same cut-
off, while the turbine rate decreases with
increased load.

Another correction which in general
should be applied to the steam consump-
tion of the engine, when the exhaust is
used as described, is the necessary steam
to heat the engine condensation from
the temperature of the vacuum in each
case to 200 degrees. At full vacuum
the raise in temperature would be about
100 degrees. At atmosphere it would be
zero. This reduces the actual cost of
operation T — T' by the amount of
auxiliary steam necessary to be used in
the feed-water heater. This steam should
be added to the total steam consumption
for each change of vacuum to get the
true cost. This has not been considered

TABLE 1. DATA FOR

CURVE.S H-T-R OF FIG. 3

.S

R

D

V

L

Curve H

ConvE T

Curve R

T—T'

T~H

Lb. Steam

Lb. Steam

Outside

Supply

Return

Dit.

Latent

400 Kw.

r ■

6.50 HJ.

R

Cost T

Ten

'f.

Therm.
Deg. F.

Therm.
Deg. F.

Temp.
Deg. F.

Max.
Vac.

Heat.*
B.t.u.

ll.-,S,00

T
Rate

400 Kw.
Load

R
Rate

400 Kw.
650 U.P.

Operated
Red. Vac.

Steam

Deg.

L ^^■^

T

1

0- 5

211.1

197

14.1

3 1b.

960

17,020

47

18,800

19.5

12,675

10.560

1.7S0

2

5-10

206

192.6

13.4

0

966

16,073

43

17,200

18.5

12,025

8.960

1.127

3

10-15

200

187.3

12.7

3"

969

15,187

41

16,400

18-

11,700

8,160

1.213

4

15-20

194.5

182.5

12

6.4'

973

14,292

38.8

15.520

17.4

11.310

7,280

1.228

5

20-25

188.3

177-

11.3

9"

977

13,402

37

14,800

17-

11.050

6,560

1.398

6

25-30

181.6

171-

10.6

11.5'

981

12,520

35.2

14.080

16.6

10.790

5,840

l.r)60

7

30-35

174.9

165

9.9

14'

986

11,654

33.5

13.400

16.2

10.530

5,160

1.746

8

3.i-40

167.8

158.5

9.3

17'

993

10,853

31.4

12,560

15.6

10.070

4,320

1.707

•J

40-45

l.iS.o

ISO

8.5

19.5'

1,000

9,851

29.5

11,800

15.1

9.815

3,560

1.949

10

45-50

146.6

139

7.6

22"

1,007

8.745

27.3

10.920

14.6

9.490

2.680

2.175

11

50-55

133

126.5

6.5

24.2'

1,016

7,412

25.2

10.080

14.3

9.295

1.840

2. 668

12

55-60

117.5

112

5.5

26.2'

1.027

6,205

23

9,200

14

9.100

960

2.995

13

28'

20.6

8,240

l,l.'j8,7(Xl lb. water circulated per hour.

f T' full vacuum 1,545 X ordinate r,,
1 R' full vacuum 1,545 X ordinate /f,.

M T' no vacuum 1^545 X ordinate T\
Lf/' steam 210° 1,545 X ordinate tf.

•Old values used before Marks and Davis tables were adopted.
1,545 X 8.240 lb. = 12.730..sao.
1.545 X 9,100 lb. = 14.059.500. Fig. 5

1,545 X 18,000 1b. •= 27,810.000. /f steam 212'> 3491 X 17,000 1b. = 59,347,000.

1.545 X 17.000 lb. ■= 26.265,000.

inches from the quantities corresponding
to the various vacuums given in Table
1, the column under 7" — T' is obtained.
These figures indicate the cost in pounds
of exhaust steam of utilizing the exhaust
steam for the heating system and run-
ning the turbine under partial vacuum.
T — ^ W is the excess steam in any case
available for further additions to the
heating system.

Particular attention is called to the
fact that the curves T and H are similar
for nearly iheir entire length and that
with a constant load by changing the
vacuum the proper steam supply at the
proper temperature is available to heat
the circulating water of the heating sys-

'■ TTI.

The turbine load can be decreased
shghtly or more surface added to the
heating system and \\\t curves T and H
will nearly coincide. The exact figures
are given in column T — W. Table I.
The minimum difference is 1127 pounds
and the maximum 2095 pounds, but in
the latter case, by observing curve H,

variation in load or wide range of vac-
uum as the valve setting and receiver
pressure have to be readjusted.

Considering the flexibility of the tur-
bine for change in load and vacuum,
ease of operation, floor space, and slight-
ly better steam consumption for over-
loads and full vacuum, the economy of
the turbine is fully as good, if not bet-
ter, than the reciprocating engine for
exhaust hot-water heating with partial
vacuum on units of over 250 kilowatts.
Fnginecrs in general have been reluctant
to reduce the vacuum on large turbine
units on account of the rapid increase
in steam consumption, but a study of
the arrangement in Fig. 1 and the charts
will show the advantages to be derived
from this practice.

In makinc the comparison of the tur-
bine and reciprocating engine the num-
ber of hours operation (about 1.500) in
summer when no heating is required
should be taken into account when the
steam consumption of the reciprocating
engine under the same load and full

in this discussion on account of com-
plicating the subject.

Up to the present, the only method of
using the exhaust from turbines for heat-
ing has been under atmospheric or slight
back pressure, or at a rate of about 50
pounds per kilowatt-hour. With the ar-
rangement shown in Fig. 1 the steam
consumption is reduced to about 30
pounds average, or less, for all of the
steam used in the heating system.

The steam consumption of any heating
system when all of its surface is turned
on is absolutely lixcd by the teirpera-
lure of the pipes and the tcmper.tiure
of the room. The steam consumption
of the turbine or engine is absolutely
fixed by the load and degree of vacuum
or back pressure whether it is required
in the heating system or not. The only
alternative in a steam-heating system
or vacuum system where the steam can-
not get below 212 degrees is to open
the windows or shut off the radiators.
The former course is the one generally
pursued, and with the rise in tempera-

422

POWER

September 12, 1911

ture of the room the oxhaust is taken
care of up to the limit set by the relief
valve. Some people have claimed that
a vacuum could be carried on an ordinary
steam job. but this is impossible mechan-
ically, beyond a few inches on account
of air leaks in the stuffing boxes, etc.
These leaks increase as the packing
gets dry and the vacuum increases.
In Fig. 3, T" would be the steam con-
sumption of a turbine operated on a
heating system at about atmospheric
pressure whether the steam was required
for heating or not. The surplus would
go out through the relief valve. Line H'
would be the steam consumption of a
low-pressure steam system less the
amount due to rise in temperature in
overheated rooms with all surface turned
on. R" would be the amount furnished
by a reciprocating engine under the same
conditions, but if the heating surface was
arranged to use the steam at 212 degrees
economically in weather 25 to 30 de-
grees outside temperature, a prohibitive
back pressure would be required in zero
weather to increase the temperature of

of exhaust heating (1500 as against 3500
hours of night and holiday heating)
makes the proposition one to be con-
sidered.

It would be possible to obtain a lower
water temperature and greater vacuum
by increasing the proportion of heating
surface in the building, but the tempera-
tures given have been found about right
for the climate in the vicinity of New
York City and do not make the cost of
the installation excessive.

Supposing the room to have a tem-
perature of 70 degrees and the water 200
degrees average for zero weather, the
difference would be 130 degrees. If the
temperature of the water were reduced
to 185 degrees it would increase the first
cost in amount of heating surface

(200 — 70) — (185—70)

130

= o. 1 15 ^ II. 5 per cent.

In a cold climate it would be eco-
nomical to make this increase, but near
New York the coldest winter temperature
average is about 5 degrees above zero

shows nearly the same range. It should
not be lost sight of that the heating sys-
tem acts as a condenser, taking a por-
tion of the regular condensing load and
reducing the injection water required in
the winter time. The curves also make
it apparent why the condenser cannot
be used as an exhaust heater where a
turbine is operated under partial vac-
uum. This opens up a field for cooling
towers and air condensers where here-
tofore the exhaust-heating problem seven
months in the year has eliminated them
from consideration.

Although this plant is operated 24
hours a day the writer has used the
data in Table 2 to show how the steam
consumption could be determined in a
plant when the heating nights, Sundays
and holidays is operated on live steam
due to the main engines being inopera-
tive. This table is very useful in deter-
mining the total steam on any heating
plant in the New York district. A like
chart can be made for any district by
obtaining the record of temperature,
maximum, minimum and average from

T.\BLE

2. NUMBER OF HOURS FOR EACH 10 DE

.;ree

PERIOD

OF TE.MPERATURE

FRO.M 0 TO 60 DEGREE.^, NEW YORK DLSTRICT

AVeek D.vys

HOLID.KYS

SUXD.^YS

Month

".\" Da.vs. 7

a.m.

to 5 p.m.

"B" Xight.s. 5 p.m. to 7 a.m.

"C" Days. 7

a.m. to 5 p.m.

"D" Nights. 5 p.m. to 7 a.m.

0°-

10°-

20°-

.30°-

40°-

50°-

0°-

10°-

20°-

30°-

40°-

50°-

0°-

10°.

20°-

30°-

40°-

50°-

0°-

10°-

20°-

30°-

40°- 50°-

10°

20°

30°

40°

.50°

60°

10°

20°

30°

40°

50°

60°

10"

20°

30°

40°

50"

60°

10°

20°

30°

40°

50° 60°

Oct

5

35

85

56

140

10

30

28

21

63

Nov....

90

105

20

168

105

14

35

45

119

14

Dec ....

25

100

SO

211

70

175

28

14

15

45

10

15

56

70

14

Jan

10

60

135

25

28

14

84

161

14

5

25

35

• 15

10

56

Feb

10

15

40

95

35

15

14

28

70

105

2K

21

5

40

25

14

li

84

14

Mar

5

90

90

oh

21

168

84

49

5

35

15

42

70

April . . .

5

35

155

14

133

154

10

40

70

42

May

0

100

28

154

25

1

28

28

Total

10

50

205

500

350

430

42

112

350

644

462

.532

25

110

110

130 1 no

14 1 77 164

217

189

203

Percent.

0.19

O.99I

4.07]

9.94

6.95

8.54

0.83

2.23

6.9o|

1-2M

9.2

10.6

0.5

2.19

2.19 2. .58, 2.19

0 27| 1..53I 3.26 4.3

3.76; 4 04

Total

1

545 h

Durs

30.6s

3er ce

nt.

2

142 he

UIS

42.6 p

er cen

.

4

85 hoi

irs 9

65 pe

r cent

864 hours 1

■.16 per cent

3491 hours 69.32 per cen'.

the radiation, as well as additional live
steam because the radiation is fixed
and the only way of varying the supply
of heat is by varying the temperature
of the steam. This is the reason for
poorly heated buildings during sudden
cold snaps. It is also the reason why
many owners think they are getting the
heating for nothing when using the ex-
haust. The steam from the engine may
balance the heating and both be ex-
cessive.

The data in regard to the use of the
steam for heating in this plant are the
result of many months' operation and
are absolutely reliable. They show that
the heating steam with all surface turned
on varies from 6205 pounds at 60 de-
grees outside temperature to 17,000
pounds in from 0 to 5 degrees weather
outside. This shows the main saving in a
hot-water plant whether exhaust or live
steam is used to heat the water. It also
explains why many mills use live steam
for heating at high pressure. The cost
of the plant and comparatively few hours

and it is the better practice to maintain
the temperatures as given. In general
it is best to proportion the heating sur-
face so that no vacuum will be carried
in the coldest weather.

In designing a plant of this character
experience is necessary in proportioning
the heating surfaces of heaters and
radiators so as to keep the initial cost
down and still operate the engines eco-
nomically. Excessive back pressure and
high temperatures of water will cause
the plant to be operated entirely on live
steam in colder weather, as the engines
will not be capable of carrying the load
with back pressure. High velocities in
the mains, minimum drop in temperature
and ample pumping capacity are abso-
lutely essential for proper operation.

The decrease in steam consumption
on the turbine with a 400-kilowatt load
between no vacuum and full '-acuum is,
according to Table 1, 10.560 pounds, and
the change in steam requirements on
the heating system between 0 and 60 de-
grees is 10,815 pounds per hour. This

the United States Weather Bureau oEBce
in that district for each day and month
of the heating season. These are plotted
on regular thermometer charts, making a
day operation of 10 hours and night op-
eration of 14 hours and indicating holi-
days and Sundays by washed spaces of
heavier or lighter color. The weather
clerk can usually give a typical daily
curve for that district and the minimum
and maximum temperatures occur gen-
erally at the same hour each day. These
temperature charts when pasted together
give a continuous cune of temperature
for the month with the night and day
periods for week days, Sundays and
holidays clearly indicated. A heavy line
may then be drawn through the average
for each 5- or 7-hour period. The total
number of hours for each 10-degree per-
iod of outside temperature can be ob-
tained and tabulated for use as in
Table 2.

In Table 2. A shows the engines would
be operated in the ordinary industrial
plant and exhaust steam available 1545

September 12, 191 1

POWER

423

hours or 30.68 per cent, of the time and
shut down 3491 hours or 69.32 per cent.,
when live steam would have to be used
for heating. In case night operation or
two shifts a day were under discussion
the night periods would amount to B, or
2142 hours additional.

Many engineers have tried to use
monthly averages in figuring heating, but
an inspection of these tables shows
February with 15 hours at 50 to 60 de-
grees, and all months have periods at 40
to 50 degrees. With the wide range in
heating requirements shown in Fig. 3, a
monthly average would not give true re-
sults.

In Fig. 3 the heavy lines are drawn
across the chart to show graphically the
relative time taken up in one year by each
temperature period. The heavy lines
at the top indicate night and holiday op-
eration (B ~ C -^ D, Table 2 1 with live
steam; and the heavy lines at the base
show the time the engines were operative
under different vacuum requirements.

Fig. 4 shows graphically the pounds
of steam and the number of hours for
each range of temperature. The total
length of the chart is 1545 hours, or the
total period of engine operation.

Fig. 4 shows graphically by the areas
the total pounds of steam required per
heating season for each !0-degree per-
iod of temperature. The length of the
chart is 1545 hours, or the total period
of engine operation. The ordinates are
the average period taken from curve H,
Fig. 3, and from Table 1, multiplied in
each case by the number of hours A,
Table 2. The area below line H is the
sum of these products or the steam
required for heating during the day
schedule, or 1545 hours per year. The
requirements in this particular case were
15,364,260 pounds. The total cost of
using the exhaust of the turbine under
partial vacuum, T — 7", is found in like
manner to be 5,818,000 pounds. The lines
T", T, /?', /? " W, Fig. 4, were plotted from
Table 1 for 1545 hours in each case. R"
is the requirement of a reciprocating
engine running noncondensing.

Fig. 5 shows in like manner the pounds
of steam required for the heating sea-
son, nights, Sundays and holidays, when
the engines are inoperative. The total
length of the chart is B - C 4 D, Tabic
2, for each lO-degree period, or 3491
hours. The ordinates for H were taken
from Table 2 and Fig. 3, and the total
area H, Fig. 5, is 36,102,377 pounds, or
the steam required for night and holiday
heating by the hot-water system. In
Fig. 5, H' is the amount of steam re-
quired for 3491 hours with all surface
in operation and the medium at 210 de-
grees. This amounts to 59,347,000
pounds.

Areas // and H'. Fig. 5, show the rela-
tive economy of hot water for heating
versus low-pressure steam with a vac-
uum system if there were no exhaust

steam available, and indicates an in-
crease of about 65 per cent, in steam with
all surface in operation for the latter.

If the outside weather were constant
in temperature there would be slight dif-
ference in economy between the steam
and water, but with the daily and hourly
variation an economical heating system
requires a medium of high specific heat
as well as one possible of as wide varia-
tion in temperature.

By dividing the pounds of steam by
the water evaporated per pound of coal,
the number of pounds may be determined
and knowing the cost per ton these fig-
ures may be readily transformed into
dollars.

consumption under full vacuum, or area
7", less the excess steam space T' — H.
It also shows that the greater the econ-
omy of the engine under full vacuum the
less the apparent saving by the use of
exhaust steam for heating. The steam
spaces T — H represent the steam going
to the condensers. The net saving by
operating partially condensing in the
case under consideration over using live
steam for heating would be

T — {T — H)

H

12,730.800 — 3,185,140

15,364,260

= 62 per cent.

-T5_

•S

§ 15.000

2S

"

.._.

y^.?-

1

Vii_

._

_.

(£

T-H '

D

1

;J^iiz:

r "t-'h

......

T

E 5

"'

~''~:

wMm^'.

'^AWi^Z^d^^

If "T"t

•^'

— 1- —

-205 Hr.

5001
50°-

lours
40°

w

Hour
f-50

'^ 5000

430 Hour";

M

ZC

°-30°

4(.

50° -60

0

0

750 1000

Hours

Fig. 4. Areas Giving Total Steam per Season

2aooo

: 15.000

• 10,000

'■:7!^.C>,

'>/...///.

■'Z07//,

WP7/A

W^,

H'

^^^///.

^5^^

777^/.

Tm-.^:

^%?;

11

■':■'/>

'///////

y/////,'..

■////...,

-

T
§

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1

6?4

Hour:

97/

Hour

s

7SI Hours

20'

-30°

ZO

"-40

°

40°

50'

845 Hours
i:n°^-cn°

1500 EOOO

Hours

Fig. 5. Periods of Live-steam Operation

The cost per 1000 pounds of steam, al-
lowing $3 per short ton of 2000 pounds
for coal, handling ashes, etc., at 9 pounds
of evaporation will be

1000 X .^00

^ 17 (enl\ nearly

2000 X 9

In showing the amounts represented by
the relative areas in Fig. 4, the least cost
of heating and power combined, T, was
taken as 100 per cent, and tabulated as
shown in Table 3.

Fig. 4 illustrates the economy effected
by using the exhaust steam under partial
vacuum and that it is equal to the steam

The actual amount will be 9,546,600
pounds at 17 cents per 1000 pounds of
steam, or SI622 per season of 1545
hours.

The least cost of heating and power,
night and day, on a plant operated as
described would be, from Table 3, Figs.
4 and 5,

S3 153 1 .S6140 = $9293

If the turbine were operated at at-
mosphere and the system on a medium
at 210 degrees, or steam at atmosphere,
the cost would be 7"", Fig. 4, and H',
Fig. 5, added, or

$10,090 + $4688 = SI 4,678

424

POWER

September 12, 1911

This is

514,678 — S9293 = $5385
an increase of 58 per cent. If tiie tur-
bine were operated at 400 kilowatts for
1545 hours under partial vacuum, the
rate per kilowatt-hour obtained from the
exhaust steam used on the heating sys-
tem would be, from T", of Table 3,

18,549,000

= 30 pounds per kilowaii-hoiir

■ 45 pounds per kilowatt-lumr

400X1545

The rate per kilowatt-hour, if the ex-
haust steam were used at atmosphere,
would be, from T", Fig. 4 and Table 3,
for the same load and period
27,180,000
400 X 1545
This shows a gain of 50 per cent, in
power by using the exhaust steam under
partial vacuum, over using it at at-
mosphere.

The saving by the use of the exhaust
steam on a vacuum system shows
greater apparently than a hot-water sys-
tem such as described, but the heating
and power combined would be 50 per
cent, greater. If the steam for heating
balances the power steam the amount
can be indefinitely increased and a
greater saving apparently shown by the
use of exhaust steam for heating.

Many claim that it is unnecessary to
operate the heating system continuously
when using steam as a medium, especial-
ly nights. There is of necessity a sur-
plus of heat on a steam system in aver-
age weather (which, it is often claimed,
costs nothing, because it is a byproduct),
but it is considerable trouble ,to start
circulation and relieve the system of air,
and from actual tests it takes more
steam to operate a large plant intermit-
tently, allowing the building to cool, than
it does to maintain continuous operation.

Automatic heat control is used suc-
cessfully to reduce the steam consump-
tion and overheating by shutting off the
surface, but the first cost and mainte-
nance give the hot-water system the
advantage.

In making these comparisons the loss
in mains and pumps for circulation has
been disregarded, but experience proves
that with a properly arranged plant the
expense is in favor of the water system.

The reciprocating engine would be less
economical in summer by the area R' —
T. If the heating surface was con-
stant on a vacuum-steam system and the
engine operated at atmosphere, or 210
degrees at the period 30 to 40 degrees.
Figs. 3 and 4 show that live steam would
be required for the colder periods, and
the period 0 to 10 degrees would also
require a greater temperature of the
medium by 30 degrees, or 10 or 15
pounds back pressure. This might re-
quire the engine to be cut out of the
heating system and live steam to be used
in extreme weather, causing enormous
increase in boiler power at the peak of
the heating load.

The problem in this article contem-
plated the constant load of 400 kilowatts,
but on the plant in question the load is
variable, ranging from 200 kilowatts at
noon to 600 kilowatts at night for 24
hours. When a variable load is under
consideration, a chart should be worked
out for the heating in pounds of steam,
as in Fig. 3, and one for the daily load,
showing the average hourly variations
for 24 hours. With pounds of steam as
ordinates and hours as abscissas, the
curves of steam consumption for each
5 inches of vacuum between full vac-
uum and atmosphere should be plotted
for the engine or turbine for the average
daily load, showing the hourly variations.
From these charts one should be con-
structed for each 10-degree period from
0 to 60 degrees with pounds of steam
as ordinates and hours as abscissas.
Each chart will have four curves: the
typical curve of temperature outside,
showing the hourly variation; the turbine

starting up a second machine is avoided
and a great waste of steam due to high
load and low vacuum is prevented.

There are cases where it has been
recommended to take steam for heating
and other purposes from the receiver be-
tween the cylinders of a reciprocating
engine and from a turbine between the
stages. This has resulted in a number
of fallacies as to economy. The governor
on a large engine will not regulate for a
greater range in total steam consumption
than the equivalent of no vacuum and
full vacuum, or from 25 to 30 per cent,
and generally less. When the pressure
on the receiver of a reciprocating en-
gine is lowered sufficiently to require a
reducing-valve connection, the steam may
be taken from the main steam pipe with
as good results. The turbine will like-
wise show an increase in steam consump-
tion per kilowatt when the stages are
tapped that will indicate a reduced econ-
omy from the practice. It can be done.

TABLE 3. COST OF HEATING

Areas or Fig. i

Pounds Steam

Per Cent.

Cost at 17c.
per JI.

18,549,400

100

S3, 153

15,364,260

83

2,612

12,730,800

68

5,818,600

32

989

T — H, excess strain for extension of work on condenser

3,185,140

17.2

741

27,810,000

150

26,265,000

142

4,465

15,079,200

R' — 7", economy of turbine over reciprocatingengine.summer.

1,328.700

7

226

T' + H, lieating by live steam, hot water and condensing tur-
bine

28,095,060

151

Areas of Fig. 5

36,102,377

100

6,140

59,347,000

164

10,090

Steam consumption at full vacuum; the
heating curve in pounds of steam, and
the curve of actual steam consumption
of the turbine at the hourly loads.

By dividing the hours. Table 2, by 24,
the number of days can be obtained for
each 10-degree period of temperature.
When the areas between the curves on
each of the six charts are determined and
multiplied by the number of days in
each case, the heating, excess steam and
cost of reducing vacuum can be deter-
mined for the season.

When the load is at the peak, one ma-
chine may not carry it at reduced vac-
uum. It is economical then to turn the
turbine into the condenser with full vac-
uum, especially when the- peak is of only
two or three hours' duration. The cir-
culating pump will continue to operate
but no heat will enter the system. Be-
fore and after the peak occurs the vac-
uum may be lowered and 10 degrees
higher temperature than the weather re-
quirements demand may be carried on
the water system. By thic arrangement

however, if less than 10 or 15 per cent,
of the steam required to operate the ma-
chine is taken in this manner. If the
turbine or engine is especially designed
with high-pressure parts of greater capa-
city for this work the machine will be
uneconomical if at any time the condi-
tions are reversed and the steam is not
needed in the heating system. In any
case it is the consensus of opinion that
taking the steam in the manner indicated
between the engine and condenser is far
more economical than tapping the stages
of the turbine or receiver of the engine.

Hot-water heating would be especially
advantageous in connection with low-
pressure turbines and reciprocating en-
gines, using cooling towers in case in-
jection water was not available. The
charts show that over 50 per cent, of
the exhaust steam required in zero
weather for heating would be available
for power 80 per cent, of the time.

The writer is indebted to W. E. Van
Patten, chief engineer at the Hoboken
terminal, for the records of operation.

September 12, 1911

POWER

425

First Annual Meeting of the

Institute of Operating

Engineers

The Institute of Operating Engineers,
which was incorporated under the laws of
the State of New York on June 22, has
held its first annual ineeting. The first
session was opened with a brief speech
by Prof. W. D. Ennis at 10 a.m.. Friday,
September 1, in the Engineering Societies
building, West Thirty-ninth street. New
York City. Some 50 delegates and mem-
bers were present.

Ex-Congressman William S. Bennet
gave the address of welcome. In speak-
ing of the Institute he said that it typified
the old American spirit of progress and
he felt that there was a bright and useful
future for it.

J. C. Jurgensen, founder of the In-
stitute and provisional chairman, made
the reply. He went a little into history,
telling how the idea of the Institute was
developed.

Several short addresses followed Mr.
Jurgensen's speech.

Fred R. Low spoke on "The Operating
Engineer's Future." Mr. Low said that
one great trouble of the present day is
to emphasize the difference between the
man who simply runs his engine and the
man who brings to bear upon the op-
eration of his plant all the training,
thought, interest and experience of a real
engineer. To do this is one of the cardinal
purposes of the Institute.

The increasing opportunities of the
thoroughly trained power-plant engineer
make it more than ever worth while to
Mudy and train. The increasing import-
ance, responsibility and remuneration of
such a man will aid in putting the whole
vocation on a higher plane.

D. B. Heilman, of Reading, Penn.,
chairman and commissioner of District
No. 3, said a few words on "The Engi-
neer's Place in the Community." He
told how the general public seldom gave
thought to the man who bears the re-
sponsibility of keeping the wheels turn-
ing. This state of affairs is passing,
however, because of the wider dissemina-
tion of information and because of the in-
creasing uses and importance of mechan-
ical power. The Institute will serve to
hasten the time when the engineer will
he accepted at his true value and his im-
portance in the community will be fully
realized and acknowledged.

A. C. Dougall was to have spoken on
"The Employer and the Engineer," but
was prevented from attending the meet-
ing. A. R. Maujcr spoke extemporane-
ously in his stead. He said that there
seemed to be a lack of proper sympathy
between the employer and the engineer.
This was due, he thought, to ignorance;
ignorance on the part of both. The blame
rests, perhaps, chiefly with the engineer:

first, in not taking full advantage of his
opportunities, and, second, in not demon-
strating his worth and importance to his
employer.

J. P. Fleming, of Chicago, chairman of
the T. Ji Waters Branch, spoke briefly
of the progress which has been made by
the Institute in Chicago. The Waters
Branch expects to offer a course of high-
grade lectures on steam-engineering sub-
jects during the coming fall and winter.
The outlook seems good for increased
membership in the Chicago district and
valuable activity is expected in the way
of educational work.

.^fter the speeches the following com-
mittees were appointed: Committee on
constitution and bylaws, A. L. Rice, Chi-
ago; W. G. Freer, New York; J. A.
Pratt, Philadelphia; Willis Lawrence,
New York, and V. L. Rupp, Philadelphia.
Nominating committee: R. D. Tomlinson,
Milwaukee; J. L. MacVicar, Boston; H.
M. Elder, Richmond, Va., and Fred R.
Low, New York. Finance committee:
D. B. Heilman, Reading, Penn.; J. C.
Stewart, New York; R. D. Tomlinson,
Milwaukee; J. P. Fleming, Chicago, and
H. W. Geare, New York.

At the afternoon session three tech-
nical papers were read. The first one,
"Temperature Changes and Heat Trans-
mission," by V. L. Rupp, will be found
elsewhere in this issue. The second,
"Boiler Room Analysis of Coal," by J. P.
Fleming, consisted of a description of a
simple method of making a proximate
analysis with a fair degree of accuracy
without employing any very expensive
pieces of apparatus. The main point
seemed to be the use of large samples so
as to offset errors in weighing. The third
paper, "Cooling Towers versus Steam
Pumps," by H. W. Geare, although af-
flicted with an irrational title, proved to
be interesting, because it illustrated what
a little study of conditions and plant
layout may produce in the way of im-
proved economy when applied. The paper
described how changing from the use of
sea water for condensing purposes to
fresh water recooled in forced-draft cool-
ing towers effected a direct saving of
nearly S10 per 24 hours besides produc-
ing more satisfactory and reliable op-
erating conditions.

In the original installation the sea
water was pumped about 1000 feet to
the condensers by duplex steam pumps.
The friction and radiation losses and the
high steam consumption of the pumps
resulted in very poor economy. By in-
stalling two forced-draft cooling towers
of such ample size that for eight months
in the year they may be used as natural-
draft towers and by using electrically
driven circulating pumps much better
economy was secured.

The discussion of these papers was
brief, principally on account of their
nature, and an early adjournment of the
session was made in order to allow the

various committees to get to their
work.

At the evening session Professor Ennis
gave an able address on "The Profes-
sional Spirit," and J. A. Pratt, director
of the Williamson Trade School, de-
livered a lecture on "A Method of Teach-
ing Operating Engineering." Professor
Ennis' address will be printed complete
in a later issue. Mr. Pratt's lecture, which
was illustrated with stereopticon views,
described the methods employed in teach-
ing operating engineering at the William-
son school. The preface to the lecture
proper was a rather complete survey of
the present status of operating engineer-
ing and an expression of Mr. Pratt's opin-
ion of the value of the Institute in rais-
ing both the vocation and the men to a
higher plane. An abstract of his lecture
will be published later.

The meeting of Saturday morning was
devoted entirely to the transaction of
business. Messrs. Heyrodt, Briner and
Sword were appointed ballot tellers and
instructed to retire to examine and re-
port on the postal vote recently cast by
the Institute membership for the elec-
tion of the candidates to the various
grades. They reported that all members
listed on the ballot were elected to the
grades under which they had been
scheduled.

The treasurer's report was then made.
From March 10, 1910, to September 1,
this year, the total receipts for initiation
fees and dues were S2284.41. The total
expenses were $2156.65. In the course
of his report, the treasurer pointed out
that the expenses during the past year
were necessarily high; office furniture, a
typewriter and a duplicating machine
were purchased, the prospectus pamphlets
were printed and much postage expense
was incurred through the dissemination
of missionary literature.

The report of the committee on edu-
cational requirements was next heard.
This committee has compiled and had
printed a list of requirements for the
various grades, which is to be used as a
guide in grading the candidates. A copy
of the list may be obtained by application
to the secretary.

The committee on apprenticeship re-
quirements has prepared a similar list
which also is obtainable from the secre-
tary.

The committee on vocational statistics
was compelled to suspend its activities
because of greater need for the efforts
of its members in other directions. It
hopes, however, to get local committees
started in the near future for the col-
lecting of data on the size and condition
of plants, wages, hours of work. etc.
During the past year this committee has
been called upon to place 17 men. In
one case an Institute member was sent to
a plant in New Hampshire to take a
position where he is now drawing a
salary of S240 per month.

426

POWER

September 12, 1911

The finance committee reported that
;iie books of the treasurer had been ex-
amined and found in good order.

The committee on constitution and by-
laws brought in a report in which many
changes in the constitution were recom-
mended. The governing idea of the com-
mittee was to simplify the constitution
as much as possible and transfer to the
bylaws all matter which is not strictly
fundamental law.

After a long discussion, in which strong
arguments were advanced by both sides,
a motion was sustained changing from
14 to 12 the number of years of prac-
tical experience required of a candidate
for the degree of master operating engi-
neer. Provision was made to make a
completed four-year course in a recog-
nized college equivalent to two years of
practical experience. Another proposed
change gives the power of election of all
candidates for all grades to the board of
control. Heretofore candidates have been
elected by the vote of the entire member-
ship. The initiation fee for journeyman
machinery operators was reduced from
$10 to S5; for the senior apprentices,
from S5 to S3 and the registration fee
for the junior apprentices was reduced
from S5 to $2. The quarterly dues of the
machinery operators were reduced from
S2.50 to SI. 50 and of the senior ap-
prentices from SI. 50 to SI.

The nominating committee submitted
the following list of nominees for office
and they were unanimously elected:
President, J. C. Jurgensen; vice-presi-
dent, for one year, Willis Lawrence; vice-
president, for two years, W. D. Ennis;
vice-president, for three years, J. G.
Ould; secretary, H. E. Collins, and
treasurer, \V. P. F. Hill.

It will be noticed that all officers of
the temporary organization were reelected.
In recommending the reelection the
nominating committee pointed to the great
amount of work performed by these men
and the progress made under their regime.

All of the papers read at the Saturday
afternoon session brought forth much
discussion, for the reason, perhaps, that
the topics were relative to a phase of
steam engineering which is naturally open
to much discussion, to wit, lubrication.

R. D. Tomlinson's paper, "Engine Lub-
rication," found elsewhere in this issue,
engendered a discussion as to the man-
ner of applying cylinder oil. F. L. John-
son maintained that atomization of the
oil was not necessary, stating that it was
the valve parts and cylinder walls that
required lubricating and not the steam.
He said that where the oil is atomized, 90
per cent, or more is carried in the steam
out through the exhaust pipe without ever
coming in contact with the rubbing sur-
faces at all. F. J. Curry supported the
atomization method and described an ex-
perience to bear him out. In a certain
vertical cross-compound engine the oil
was applied by direct injection close to

the throttle valve, passing into the valve
chest in solid drops. The engine valve
was slightly loose and this permitted the
oil to leak through the valve, trickle
down the valve stem and out through the
stuffing box, never reaching the cylinder
at all. Naturally, trouble resulted. The
oil-feed pipe w-as tapped into the steam
pipe higher up and carried in to about the
center. Thus the drops of oil fell out of
the feed pipe into the center and hottest
part of the stream of steam, became
vaporized and were swept into the cylin-
der along with the steam itself. The
trouble ceased after the change.

W. G. Freer, who has had long experi-
ence as a marine engineer, advocated no
oil whatever in steam-engine cylinders.
He confessed, however, to using cylinder
oil in the high-speed horizontal generator
engines of which he now has charge.

H. M. Elder testified that he had found
grease to be more economical than oil
in some uses.

The second paper, prepared by G. L.
Fales and read by F. L. Johnson, was en-
titled "Reduction of Lubricating Costs in
Smelter Power Plants." The paper de-
scribed how an impressive monetary sav-
ing was effected by the substitution of a
flooding system of oiling for sets of in-
dividual sight-feed cups. The flooding
system described in Mr. Fales' paper was
of the pressure type; that is, the oil was
fed to the parts under an air pressure of
some 15 pounds. Willis Lawrence stated
that while the pressure system may have
been satisfactory in the present instance,
the gravity system was much to be pre-
ferred in the average case. With the
pressure system trouble is often experi- •
enced with the pump so churning the
oil in injecting it into the pressure tank
that it does not clear itself readily of the
air and is fed to the parts in a more or
less emulsified condition. .

Mr. Tomlinson pointed out that with a
gravity system where the storage tank is
of fair capacity, the oil supply does not
depend solely on the continuous operation
of a single pump. If the pump breaks
down a little time is available to get an-
other pump into service or even to make
repairs on the broken one.

An interesting bit of irrelevant discus-
sion was started by Mr. Lawrence. He
told how occasionally on large shafts a
patch, sometimes as large as a man's
hand, would appear, seemingly so smooth
that the lubricating oil would not adhere
to it. As the shaft revolved this patch
would come in contact with places in the
bearing which were poorly lubricated,
stick and cause heating. The surest and
best cure for this trouble, Mr. Lawrence
found, was to rub the bright spot with a
cake cf Sapolio. This would roughen the
spot and restore satisfactory lubrication.
Mr. Johnson's remedy for a hot bearing
which had developed in the manner de-
scribed by Mr. Lawrence was to draw-
file the shaft in a direction parallel to

its length. Mr. Lawrence allowed that
this was good, but argued that it was not
always feasible as the trouble might de-
velop when the engine could not be shut
down or the engine might be of such
size that the lifting of the bearing caps
would be an undertaking for several men
and a sizable crane.

The last paper, prepared by Darrow
Sage and read by H. E. Collins, was on
"Removing Emulsified Oil from Con-
densed Water." It is printed in this is-
sue.

By way of starting the discussion, Mr.
Lawrence asked : "Is it necessary to re-
move oil from boiler-feed water? If so,
how much ? In other words, what per-
centage of oil may safely be admitted
with the feed water?" His opinion is
that even a large quantity of oil is not
dangerous. He told of operating a water-
tube boiler at 300 per cent, rating and
under 200 pounds pressure with 'i inch
of oil on the tubes. In opposing Mr.
Lawrence's contention that oil was not
dangerous, Mr. MacVicar told of a tubular
boiler in which the lower front sheet
bagged down due to but a slight film of
oil on the metal. Mr. Low said that oil
mixed with scale-forming feed water un-
questionably was a source of trouble, the
scale and oil in a physical combination
forming a plastic mass w'hich when ad-
hering to the boiler shell excluded the
water so as to permit the metal to become
overheated

On Saturday evening practically all of
the out-of-town members and a large
number of the resident members visited
the Fifty-ninth street station of the Inter-
borough Rapid Transit Company. This is
the station in which the first notable in-
stallation of exhaust-steam turbines was
made. Mr. Lawrence is the chief en-
gineer for the Interborough company.

On Sunday the out-of-town members
were piloted about the city by the re-
ception committee to various points of
interest.

All who attended this first annual meet-
ing were impressed by the headway which
the Institute has thus far made and ex-
pressed the fullest confidence that even
greater strides will be made during the
coming year.

PERSONAL

John S. Baker, well known among the
electrical trade on the Pacific coast, has
been placed in charge of the offices in San
Francisco, Cal., Room 400, First National
Bank building, opened on September 1
by the Crocker- Wheeler Company, of
.■\mpere, N. J. A^otors, generators and
transformers of various sizes will be car-
ried in stock for coast shipments.

Lieutenant Walter Diman, son of
George H. Diman, consulting engineer for
the .^merican Woolen Company, has been
appointed senior engineer of the bartle-
ship "New Jersey."

27 2.'/

Vol. 34

NEW YORK, SEPTEMBER 19, 1911

No. 12

FROM Ihe lorelruck of the battleship
"Michigan" there flutters in the breeze
a silken pennant, in the center of which
is a big black ball, signifying that this big
war-machine is the chami)ion of the American
navv in battle efliciency.

It took twelve months' lianl work for 850
men to win that emblem. "Every oflicer and
every man. " said the commander, "had a
part in winning this pennant, and when I was
ordered to designate a few men whose work
was most cons])icuons, it was an almost
impossible task."

For a whole year the "Michigan's" record
for engineering competition and guimery ])rac-
tice reached the won-
flerful average of 94
])er cent.

We have often wi-^hed
that the word elVi-
ciency could be red uc
ed to a plain, one-.syl-

lable word. "Wc have words in our working
vocabulary which are shorter and, if not
sweeter, are more to the point. If tliis were
done, perhaps a fuller realization ol the
importance of "efliciency" might be had
and its projjcr tise made more common.

It means skill and influstrv; and ils attain-
ment means a thorough knowledge of one's
vocation anfl the necessarv energy to ])ut
that "knowing how " into itTect.

It was not merelv ff)r the privilege of flving
that silken j)ennant at the foretrnck of their
"power plant" that H^o men workifl un
ceasingly for a whole year. The pemiant is

but a symbol, a sign of what skill and industry
— efliciency — can accom])lish if properly
directed and ajiplied.

Xo illuminated sign is needed to blaze forth
the efliciency of a well conducted power
l^lant; its efficiency is concealed in the engine
room, in the boiler room, in the oflice — but it
is there, "below decks!"

" Rver\- officer and every man" contributed
by his labor to the efliciency of the big battle-
ship. What an illustration is served for our
field of work in this quotation! It means
that the coal-])asser (the fireman) knew his
business; that the oiler was on the alert; that
the engineer had his "finger on the pulse" of
the machinery ; that the
navigator (the o])er-
ating engineer) steered
the "straight course";
that the commander
(the chiel engineer) felt
himself ])ersonally re-
sponsible for even the
most insignificant post of duty and so dele-
gated his authority and majiped out the
duties of 8sc) men that each man was a -^
of that wonderful record of efliciencv.

It is hardly necessary to state that tlure
is no joyous looting of whistles, no loud
huzzas from the excited i)0])ulace. no extrav-
agant encomiinns from the daily ])ress when
the ])ower plant force does its duty.

We cannot ado])t navv nut hods of dechu-
ing our efliciencv. but we can strive to increase
its average, and this will be a declaration
that will certMiiilv hcl]) to fatten the ])av
envelop.

P O W K R

September 19. I9U

Priming of Water-Tube Boilers

A boiler is said to prime when the
steam leaving it carries a certain amount
of water in suspension. All water-tube
boilers will deliver steam containing
moisture, unless equipped with super-
heating apparatus, but usually this mois-
ture is not great enough to seriously
affect the operating economy or the
safety of the plant. When priming, how-
ever, the water carried over by the steam
is in excessive quantities and not only
greatly impairs the plant efficiency but
if in large bulk endangers life and prop-
erty. A certain type of boiler might
give entire satisfaction in one plant and
be a complete failure in another on ac-
count of its tendency to prime under
the operating conditions of the second
plant.

A purchaser of water-tube boilers will
usually give careful consideration to
such points as tbe heating surface, the
ultimate strength of the various parts,
ihe grate area, the stack dimensions,
etc.. but seldom gives thought to the
features of the boiler that determine its
ability to operate successfully without
priming.

The size of a boiler is determined from
the load it will have to carry, but the
type and design of a water-tube boiler
for a successful installation must be
determined from the plant conditions,
such as the quality of the feed water, the
maximum load and its durajtion, the
rate at which the load may vary, etc.
Certain feed waters contain impurities
that will cause any water-tube boiler
to prime if they are allowed to reach a
sufficient concentration, and no two boil-
ers will prime at the same degree of
concentration.

Priming may manifest itself as a heavy
continuous discharge of water with the
steam or by intermittent discharges of
slugs of water separated by intervals of
comparatively dry steam. The latter con-
dition is particularly vicious, as the
slugs are likely to wreck the piping and
the engines before the trouble can be
remedied. In the case of the continuous
discharge of water, the operating force
has usually sufficient warning to cut the
apparatus out of service before an\- seri-
ous damage occurs.

The particular points in the design of
any boiler which should be considered
with reference to its probable priming
tendency are its circulating system, the
total and effective liberating surfaces,
the steam space acting in the capacity
of a receiver and a separator, the water
space up to the normal water line and
the fluctuation in the water level at dif-
ferent rates of driving.

The results of investigations of these
live factors are given in the following
discussion. Certain types of boilers have
been taken for illustration merely be-

By 1 . F. Maguirtr

Thi /iiinldDh iildl'-

nj ,1

f^iiif^rr c/rt/f/a/nig .s

ystei)! ;

///( tinnlatiiDi in

several

"a-cll k)un<.n types of

water-

tube hoiUrs. and tlu

illjhtr

1)1 fc oj steam shaic

ualer

space, Iibeiatniii

iirjaee

mill water level.

cause they happen to be particularly well
known or involve features that are of
peculiar interest.

ClRCLLATIiNG SVSTE.M

The necessity of providing for circula-
tion may be appreciated from a con-
sideration of the elementary boiler shown
in Fig. 1. where BC represents a water
tube, inclined to the horizontal and ter-
minating at both ends in the vertical
headers AB and CD. If the ends A
and D are both open to the atmosphere,
the surface pressures in the two headers
are equal at all times, and if heat be
applied to the exterior surface of the
tube R C, steam will be generated and
it will travel toward B, finally escaping
at /4. .'\ certain amount of water will be
carried along by the steam on its way
through the tube, even up to the water
surface in the header .4 B, and it is evi-
dent, therefore, for the simple arrange-
ment here shown that a path must exist
in the header A B and in the tube B C for
the return of the water. When this ele-
mentary boiler is operating there are
two distinct fluids circulating in A B and
C D in opposite directions, one consist-
ing of a mixture of steam and water,
the other of water alone. With a low
rate of driving this boiler would work in
a fairly satisfactory manner as the two
oppositely moving fluids would not great-
ly interfere. As the rate of steam gen-
eration increased, however, the tendency
of the steam to pick up water would
increase in even greater proportion, and
the fluid velocities would rapidly increase,
resulting in a marked interference be-
tween the two opposing currents. As
the rate of driving was further increased
the interference would finally cause the
boiler to prime excessively or boil over.

.\n interesting point to consider in the
operation of such an elementary boiler
as that shown in Fig. 1 is the difference
in water level that exists in the headers
A H and C D. With the application of
heat to H C, a certain amount of steam
must exist in all parts of B C and up to

the water level in the leg A B. For static
equilibrium the pressure at the lowest
point C, due to the weight of the steam
and water in ABC. must be equal and
opposite to the pressure due to the solid,
body of water in the leg C D, as the twfll^
pressures on the surfaces of the fluidr
in A B and C D are the same. It is a
simple matter to show that the difference
in water levels in the legs A B and C D
depends upon the proportion of steam
to the water in the length ABC and that
the harder the boiler is driven, the greater
will be the difference. This difference
in the water level is present in certain
commercial water-tube boilers, notably
those of the cross-drum type, and is due
to the varying proportions of the steam
and water in certain parts of the boiler.

The boiler shown in Fig. 1 would not
be a success commercially, as it would
prime excessively, on account of the two
oppositely moving fluids in the same
tubes or headers. To eliminate this effect
a return circuit must be supplied from
the front header A B to the rear header
C D. This may be done by providing
a horizontal connection at the top be-
tween the headers, as shown in Fig. 2.
Here the steam leaves the water at A
and the water carried up the leg A B is
conveyed by the element A D back to
the rear header C D. thus minimizing the
countercurrent effect in .4 B C.

The horizontal section A D may be
parallel to B C or inclined without af-
fecting the circulation. Such an arrange-
ment is shown in Fig. 3 and is well
worth considering inasmuch as many well
known water-tube boilers are designed
in accordance with this fundamental ar-
rangement.

The manner in which heat is applied
to a boiler has an important bearing upon
the circulation. In Fig. 2 the application
of heat to the horizontal section A D
would in itself cause no positive cir-
culation in either direction. The appli-
cation of heat to any part of the section
ABC would produce a positive circula-
tion in the direction C — 6. while heat ap-
plied to the section C D would produce a
circulation in the direction B — C. With a
simultaneous application of heat to the
entire circuit A B C D. the direction and
velocity of the circulating fluid would
depend upon the relative proportion of
steam to water in the two sections .4 B C
and CD. In Fig. 3 the application of
heat to any part af A B C would cause a
circulation in the direction C — B through
tht entire circuit, while an application of
beat to .4 D C would cause a circulation
in the reverse direction. If heat be
simultaneously applied to the entire cir-
cuit .4 B C D. the direction of the cir-
culation will depend upon the relative
amounts of steam generated in .4 B C
and ADC.

September 19. UM 1

POWER

429

In Fig. 4 is shown an elementary boiler
consisting of two inclined tubes and one
horizontal tube, all three terminating in
the two headers A B and C E. The ap-
plication of heat to A B C would produce
a circulation in the direction C — B in
A B C; A—D in A D and A—E in A E D;
while the application of heat to >1 D
alone would cause a circulation, in A D
in the direction D — A. in ABC in the
direction B — C and in A E D in the direc-
tion A — E. With heat applied to the hori-
zontal tube A E alone, the direction of
circulation would be indefinite.

Types of Boilers — Babcock & Wilcox

The Babcock & Wilcox type consists
of a nest of straight water tubes in-
clined 3 inches to the foot, the tubes
being expanded at both ends into sec-
tional headers, which in turn are con-
nected by suitable nipples and cross
boxes to one or more horizontal longi-
tudinal drums. This boiler is usually
provided with two vertical baffles by
means of which the gases of combus-
tion are compelled to travel three times
across the nest of inclined tubes and
approximately at fight angles to them.
The rate of steam generation differs
greatly for the various parts of the heat-
ing surface. The bottom rows of tubes
in the first pass do considerably more
work than the top rows in the same pass.
while the top rows in the second pass
exceed the work of the bottom rows, the
reverse being true for the third pass.
But the difTerence in the rate of steam
generation is far greater between the
lowest and highest rows in the first pass
than in the second pass, and for this rea-
son the steam generated during any given
time is greater in the bottom rows of
tubes, considering the entire tube lengths,
than in the top rows, the rate of steam
generation for the intermediate rows
varying according to their positions. This
varying rate of steam generation is
caused by the gases at the highest tem-
perature impinging upon the lowest tubes
in the first pass and also because the
lengths of tubes enveloped by the gases
decrease as the gases rise through the
first pass on account of the decrease in
the volume of the gases and their ten-
dency to crowd toward the top of the
bafBes. If the furnace is placed directly
under the first pass the radiant heat
from the fuel bed will further increase
this discrepancy.

Considering the circulation In this type
of boiler, each front header discharges
into the upper longitudinal drums through
a single nipple, and there being but one
ipplc for each vertical row of tubes.
- hich is of the same diameter as the
water tubes, it follows that there is a
decrease in the cross-section of the cir-
culating path at the point where the nip-
ples connect to the headers. In a boiler
twelve rows high the cross-sectional area
"f the nipples would be but H..S per

cent, of the total cross-section of the
tubes. .As the water level is carried on
the center line of the upper drums there
is a considerable head of water over the
front and rear nipples and the circulation
is usually assumed to be from the rear
to the front in the inclined tubes, through
the front headers and nipples into the
overhead drums, back through the drums

Fig 4
EllMKMSKV Br)ILERS

and down the rear nipples to the rear
headers. If the flow is from the rear to
the front in all of the Inclined water
tubes, then the entire discharge of each
vertical row must pass through one nip-
ple. Such a circulating syslcin would
conform to the simple boiler shown In
Fig. 2. It is quite likely, however, that
the circulation does not occur entirely In
this manner.

As there is much less steam generated
in the top rows of tubes than in the bot-
tom rows, there is less tendency for the
contents of the top tubes to move from
the rear to the front. Also, the relative-
ly small areas of the front headers and
nipples produce a throttling effect which
creates a force in opposition to the flow
from the rear to the front of the tubes,
and this force is greatest at the top
row of tubes.

For these reasons it is likely that part
of the circulating water in a Babcock &
Wilcox boiler flows, at certain loads,
from the front to the rear headers
through the upper rows of tubes. How-
ever, the steam generated in these upper
rows flows to the front, causing a double
flow in the- tubes.

Hkink Boiler

The Heine boiler consists of a nest
of straight water tubes inclined to the
horizontal at 1 inch to the foot, the tubes
being expanded at both ends into the
headers, extended and riveted to the over-
head lonijitudinal drums. This type
differs from the Babcock & Wilcox type
in that the front and rear headers each
consist of a single chamber instead of
many sections and are formed of riveted
steel plates suitably strengthened by
staybolts. In addition the headers are
riveted to the overhead drum or drums
instead of being connected by nipples.
In order lo simplify the construction of
this boiler and make the front and rear
headers the same size, the longitudinal
overhead drums are set with their axes
parallel to the tubes, making the water
level in the drum, when the boiler is
not in service, iiuich higher at the rear
than at the front.

The method of baffling is different from
that employed in the Babcock & Wilcox
t\pe. The baffles are of the so called
horizontal type usually consisting of a
tile baffle between the first and the sec-
ond rows of tubes and extending "from
the front header to a point about 3 feet
I) inches from the face of the rear header,
and an upper baffle resting upon the top
row of tubes and extending from the
rear header to a point about 3 feet from
the face of the front header. With this
arrangement the hot gases pass to the
rear of the setting below the lower baffle
and enter the nest of tubes through the
opening between the end of the lower
baffle and the rear header; they then
pass along the tubes to the opening be-
tween the top baffle and the front header
and finally travel under the drums lo
the rear of the setting where they escape
to the breeching. As the tendency of
the hot gases is lo rise, it is probable
that they hug the upper baffle and there-
fore the front section of the tubes, just
above the lower baffle, is short-circuited.
Obviously, the bottom row of tubes in
this boiler does far more work in pro-
portion to the other rows than the lowest

430

POWER

September 19, 1911

row of a boiler with vertical baffles, and
inasmuch as the gases tend to hug the
upper baffle the highest rows do more
work proportionally to the remaining
rows (excluding the lowest row) than do
the highest rows in a boiler with ver-
tical baffles. However, as the gases
pass across the intermediate rows, it is
probable that the relative amounts of
work done decrease from the lowest to
the highest rows, only the decrease be-
tween adjacent rows is not so marked
as in the case of vertical baffles.

The area of the throat of the front
header leading to the drum is far greater
in a Heine boiler than in one of the
Babcock & Wilcox type; hence, the throt-
tling effect tending to oppose the flow
into the drum is much less. The ten-
dency of the contents of all the inclined
tubes is to flow from the rear to the
front, but owing to the relatively small
amount of steam generated in the top
row, it is quite likely (as in the Babcock
& Wilcox type of boiler) that a certain
amount of the water returns from the
front to the rear header, through the
upper rows, the steam generated in these
return tubes flowing, however, to the
front and creating a counterflow. As in
the Babcock & Wilcox type, the direc-
tion of the circulating water in some of
the tubes may change, depending upon
the rate at which the boiler is driven. In
boilers of the Heine type, in which the
axes of the overhead drums are parallel
to the inclined tubes, the steam outlets
from the drums are at the front over
the front header, a suitable baffle being
placed over the discharge to prevent a
direct path for the flow of the steam and
entrained water into the steam piping.

Stirling Boiler

The Stirling water-tube boiler differs
materially from the two previously men-
tioned types. It consists fundamentally
of four drums extending across the set-
ting, one drum located at the bottom and
to the rear of the bridgewall, the remain-
ing three drums being suspended on a
suitable framework. One bank of tubes
connects the bottom drum with the up-
per front drum, a second bank connects
the bottom drum with the intermediate
drum and a third bank connects the bot-
tom drum with the upper rear drum. In
addition to this there are a single row
of short tubes beneath the water line
connecting the upper front and intermedi-
ate drums, a single row of short tubes
above the water line, connecting the
upper intermediate and front drums, and
a single row of short tubes above the
water line connecting the intermediate
and rear drums.

The baffles of the Stirling boiler are
so arranged as to compel the hot gases
to pass up the entire length of the tubes
connecting the bottom and upper front
drums; then down the entire length of

the tubes connecting the bottom and up-
per intermediate drums; and finally up
along the tubes connecting the bottom
and upper rear drums, from which they
escape to the breeching. As the heating
surface of the front bank is at least
equal to that in either of the other two
banks, and as the gases impinge initially
upon the front bank and travel along
its entire length before coming in con-
tact with any other heating surface, the
steam generated in the front bank is
much greater than that generated by the
remaining heating surface of the boiler.
The heating surface in the intermediate
bank does considerably more work than
that of the rear bank, but the greatest
consecutive difference exists between the
front and intermediate banks. The real
circulating system of this boiler consists
of the bottom drum, the front bank of
tubes, the upper front drum, the short
water tubes connecting the upper front
and intermediate drums and the inter-
mediate bank of tubes; the rear upper
drum and the rear bank of tubes do not
constitute a part of the circulating sys-
tem, but more nearly resemble a feed-
water heater.

The inclination of the tubes connecting
the bottom and the three upper drums
being great, there is a tendency for the
contents of all the tubes to flow from
the bottom to the top, discharging into
the upper drums. As the rate of steam
generation is far greater in the front bank
than in the intermediate bank, it is likely
that under ordinary rates of driving no
water is returned from the upper front
drum to the bottom drum through any
of the tubes in the front bank, but that
all of the circulating water discharged
into the front upper drum passes into
the intermediate upper drum and down
through the intermediate bank to the
bottom drum. In general, there is a
double-current effect in practically all of
the tubes of the intermediate bank. The
steam generated in these tubes passes
up into the intermediate drum while the
water carried along by this steam into
the intermediate drum, as well as the
water entering the same drum from the
front drum, is conveyed by these tubes
to the bottom drum. The circulating sys-
tem of the Stirling boiler conforms in
its elements to the simple arrangement
shown in Fig. 3.

Atlas Boiler

The Atlas boiler consists of a nest of
straight water tubes inclined at 1 ' j
inches to the foot, the tubes being ex-
panded into the front and rear headers,
the latter similar to that of the Heine
boiler. However, instead of having longi-
tudinal drums, the Atlas boiler is
equipped with cross drums and the front
and rear headers are connected directly
to the cross drums without any contrac-
tion in area at the points of connection.
These two cross drums are merely con-

tinuations of the headers, being set with '
their axes horizontal and connected by
two horizontal rows of tubes. In addi-
tion to these, there is a third cross drum
above the other two and connected to
them by simple rows of superheating
tubes. The usual method of ba/fling is
the same as that employed in the Bab-
cock & Wilcox type with the rate of
steam generation varying in a similar
manner.

If all of the inclined water tubes dis-
charge their contents into the front
header, then the water must return to
the rear header through the two hori-
zontal rows of tubes connecting the front
and rear drums. If, as is usually the
case, the water line is carried at the mid-
dle of the upper row of equalizing tubes,
in the front drum, then the effective
water cross-section of the two rows of
tubes is only three-fourths of their com-
bined cross-sections. The equalizing
tubes are of the same diameter as the
inclined tubes and usually have a cross-
section about 11 per cent, or less of the
total cross-section of the water tubes.
Therefore, the effective cross-section of
the equalizing tubes for the return of
the circulating water to the rear header
is about 9 per cent, of that of the in-
clined tubes. While the throat area of
the front header of the boiler is greater
in proportion to the area of the com-
bined inclined water tubes than that in
either the Babcock & Wilcox or the Heine
boilers, yet there is a considerable de-
crease in the cross-section of the cir-
culating system at the equalizing tubes.

With the Atlas boiler operating at or
near the rated capacity, with the water
level at the center line of the upper row
of equalizing tubes in the front drum,
the water level in the rear drum is below
the lowest point of the lower row of
equalizing tubes. Hence, the water from
the equalizing tubes discharges into the
steam space of the rear header and there
is no continuous water circuit.

It is generally assumed that the cir-
culation in the Atlas boiler is as follows:
All the inclined water tubes discharge in-
to the front header and up this header
into the front drum, from which the
water returns to the rear header through
the equalizing tubes. It is likely, how-
ever, that a large part of the circulating
water returns from the front to the rear
header through the upper rows of in-
clined tubes, as the upper rows do a
comparatively small amount of work at
ordinary rates of driving.

WiCKES Boiler

The Wickes boiler is a well known
type of vertical water-tube boiler.
It consists of a nest of straight
vertical tubes expanded at the top and
bottom into two drums, set with their
axes vertical. The furnace is exterior to
the setting and by mea"s of a single
vertical baffle the nest of tubes is divided

September 19, 1911

POWER

431

into two parts, making a two-pass boiler.
The gases from the furnace travel up
along the entire length of tubes in the
first pass and down the entire length of
tubes in the second pass, escaping to
the breeching at the bottom of the set-
ting. The tubes in the first pass do much
more work than these tubes in the sec-
ond pass and it is probable that at all
rates of driving, the circulation of the
steam and water in these tubes is from
the bottom to the top. The tubes in the
second pass must return to the lower
drum the water discharged into the up-
per drum by the first-pass tubes, and
as there is a certain amount of steam
generated in these tubes, which travels
upward, there is a countercurrent effect
in many, if not all, of the second-pass
tubes. The water level is carried well
above the bottom of the upper drum and
the whole nest of vertical tubes is com-
pletely submerged, forming a continuous
water circuit.

Cahall Boiler

The Cahall vertical boiler is similar
in outward appearance to the Wickes
boiler, but differs materially in its cir-
culating system. This boiler consists of
a nest of tubes expanded at the top and
bottom into drums set with their axes
vertical, an opening being left through
the center of the upper drum for the
escape of the gases. The furnace is ex-
terior to the setting and the baffle ar-
rangement is such as to compel the gases
to pass from the furnace through the en-
tire nest of tubes from the bottom to
the top where they escape. With such
an arrangement of baffles there is but
one pass and the gases do not reverse
their direction. The tubes nearest to the
furnace do more work than the rear
tubes, but there is less difference in the
rates of steam generation by the in-
dividual tubes than in any of the pre-
viously described boilers. Therefore,
there is less tendency for the circulating
water to return to the bottom drum
through some of these water tubes. If
there were no tubes nor pipes other than
those mentioned, it would operate in a
manner similar to the elementary boiler
shown in Fig. I and would fend to prime
excessively. In the Cahall boiler, how-
ever, there is an additional pipe con-
nection between the top and bottom
drums, this connection being run out-
side of the setting. Thus, no steam is
generated in the return pipe and no op-
position is encountered by the circulat-
ing water in passing through this return
pipe. A countercurrent effect in any of
the water tubes of this boiler would be
decidedly more objeclinnable than in any
of the previously described boilers. If,
however, the return pipe is of sufficient
cross-section and is properly located,
it is unlikely that the countercurrent ef-
fect in the water tubes will be serious
enough to cause priming.

Erie City Boiler

The Erie City vertical water-tube
boiler consists of a top and a bottom
cross drum connected by three banks
of vertical water tubes, all tubes being
curved at their ends so as to enter the
drums radially. The furnace is exterior
to the setting and the baffles are so ar-
ranged as to compel the gases to travel
up the entire length of the front bank,
down the entire length of the intermedi-
ate bank and finally up the rear bank
to the breeching. The heating surface
in the front bank is somewhat greater
than that in the intermediate bank and
about one-third more than that of the
rear bank. The front bank does far
more work than the other two combined,
while the intermediate bank exceeds the
rear bank. The circulation in the tubes
of the front bank is probably always
from bottom to top, with no countercur-
rent effect. The bulk of the circulating
water returns from the top to the bot-
tom drum through the rear bank of tubes,
as there is less opposition to a down-
ward flow in this bank than in the other
two. However, as there is a small
amount of steam generated in the rear
bank, a certain countercurrent effect ex-
ists, but not enough to seriously inter-
fere with the circulation. In the inter-
mediate bank the circulation at ordinary
loads is probably from bottom to top,
although under certain conditions no
doubt part of the water is returned to the
bottom drum by the middle bank of tubes.

It would seem from the foregoing that
the ideal circulating system for a water-
tube boiler would conform to the fol-
lowing requirements:

1. All parts of the circulating system
should be so arranged as to cause no
oppositon to the flow of the water either
by frictional resistance or by the pres-
ence of a force tending to oppose the
circulation. This would necessitate all
steam generated in parts not horizontal
to flow in the direction of the general
circulation and would preclude the pres-
ence of a mixture of steam and water
flowing in one direction and of water
flowing in the opposite direction.

2. All parts of the circulating system
should be so arranged as to be below
the water levels, giving a complete water
circuit and eliminating the discharge of
water into the steam space.

3. The circulating system should be
so arranged with respect to the other
parts as to permit the steam to leave
the system at the proper points without
interfering with the circulation.

While no commercial boiler fulfils
completely these requirements, yet the
more a boiler deviates from these re-
quirements, the greater will be its ten-
dency to prime, especially at high rates
of driving.

Liberating Surface

The liberating surfaces of a water-tube
boiler are the water surfaces at which

the steam disengages from the cir-
culating system and enters the steam
space. As the tendency of steam to pick
up water varies with its velocity, it fol-
lows that the greater the liberating sur-
face, if properly located, the less will
be the moisture carried by the steam
and the less will be the amount of prim-
ing.

It does not follow that a boiler hav-
ing a large water surface has a corre-
spondingly large and effective liberating
surface; in fact, the reverse is often the
case, as most of the steam generated in
the boiler leaves the water through a
comparatively small part of the water
surface. In boilers of the Babcock &
Wilcox and the Heine types more than
90 per cent, of the steam generated is
discharged into the drums by the front
headers; and as there is a tendency for
the steam to leave the water by the
shortest path, only the water surface
directly over the front header is true
liberating surface. The remainder of the
water surface in these boilers is simply
liberating surface for the steam gen-
erated by the heating surface of the
drums. The velocity of the steam leav-
ing the water surface over the front
header would greatly exceed that at other
parts of the water surface; hence, the
steam would contain more moisture as it
entered the steam space just above the
front header than in other parts of the
drums.

In the Stirling boiler the water sur-
faces in the three upper drums are
liberating surfaces, but the amount of
steam generated in the rear bank of
tubes is so small compared to the other
two banks that the liberating surface in
the rear drum has little or no effect
upon the quality of the steam. As the
front bank of tubes generates more steam
than the other parts of the boiler, and as
all of the steam generated in this bank
leaves the water surface in the front
drum, the amount of priming in this
drum exceeds that in the middle drum.
Hence, the liberating surface in the
front drum has a far greater effect up-
on the quality of steam leaving the
boiler than has the liberating surface in
the middle drum or the rear drum.

In the Atlas boiler the water surface
in the front drum constitutes the en-
tire liberating surface of the boiler. The
comparatively small amount of steam
discharged with the water, by the equal-
izing tubes, into the rear drum enters
the drum in the steam space; hence is
not liberated from the water surface of
this drum. There is practically no steam
liberated from the water surface of the
rear header; consequently all the steam
generated by the entire bank of inclined
water tubes is liberated at the water sur-
face of the front drum.

The liberating surface of the Wickes
boiler is the water surface in the top
drum. On account of the manner in

432

POWER

September 19. 191 1

which the gases pass -over the vertical
nest of tubes the velocity of the steam
leaving the front half of the liberating
surface greatly exceeds that in the rear
half; hence the steam entering the steam
space of the drum will contain varying
degrees of moisture, depending upon the
point at which it leaves the liberating
surface.

The liberating surface of the Cahall
boiler is the water surface in the top
drum. .■\s an e.vternal circulating path
is provided for the return of the water
from the top to the bottom drum, and
as there is not a wide variation in the
rate of steam generation by the various
tubes, it is probable that the velocity
of the steam leaving the water is fairly
unifonn over the entire surface.

The liberating surface in the Erie City
vertical boiler is in the top drum directly
over the banks of tubes and on account
of the way in which the boiler is baffled,
the degree of moisture contained in the
steam leaving the water surface will not
be very uniform, but will vary accord-
ing to the location.

Ste.am Sp.\ck

Liberal steam space is a valuable fea-
ture for water-tube boilers, as it mini-
mizes the amount of moisture in the
steam leaving the boiler and tends to
prevent slugs of water from being dis-
charged into the steam line. It also
serves as a separator and receiver for
the steam after it has left the disengag-
ing surfaces. The relative position of
the steam space with respect to the
liberating surfaces has an important
bearing upon the value of the steam
space as a separator. The steam as it
enters the steam space from the liberat-
ing surfaces contains more or less water
in suspension. If. after leaving the lib-
erating surfaces, the steam is compelled
to travel for some distance at a velocity
considerably less than that at which it
left the liberating surface, a large part
of the entrained water will be dropped
mid the steam will be much drier at the
boiler nozzle. It is also essential, in
order to secure the best possible sep-
arator action, to locate the steam space
between the most active parts of the lib-
erating surface and the steam outlet.
Certain water-tube boilers have a com-
paratively large steam space, but that
part of the steam space acting as a sep-
arator is not a large portion of the
whole.

\ reciprocating steam engine operating
with the cutoff at 25 per cent, stroke
takes steam from the line for a period
corresponding to 'j of the stroke and
for the remaining .'4 no steam enters
the engine. If no steam space existed
between the engine throttle and the lib-
erating surfaces of the boiler, the veloc-
ity of the steam leaving the water sur-

face would be four times as great as it
would be if. the same amount of steam
were supplied continuously and at a uni-
form rate. Interposing a receiver be-
tween the liberating surfaces and the en-
gines tends to minimize this effect and
allows a more uniform flow from the lib-
erating surfaces, thus decreasing the
steam velocity and, therefore, its ten-
dency to carry over water. A large steam
space is especially desirable in prevent-
ing excessive priming when a heavy load
is suddenly thrown on the boiler.

In boilers of the Babcock & Wilcox
and the Heine types the entire steam
space in the longitudinal drums acts as
a receiver, but only that volume of the
steam space between the front header
and the steam outlet is valuable as a sep-
arator. The nearer the steam outlet is
to the discharge from the front header
the greater will be the tendency of the
t>oiler to prime.

In the Stirling boiler the steam space
in the three overhead drums and the
short tubes connecting these drums, acts
as a receiver; but- only the steam space
in the front and middle drums and the
connecting tubes is valuable as a sep-
arator.

In the Atlas boiler the steam space
in the front and rear header drums, in
the steam drum and in the two rows of
steam tubes connecting the steam drum
with the front and rear drums, acts as
a receiver, but practically only the steam
space available in the front and steam
drums, and the steam tubes connecting
these drums, is of value as a separator.

In the Wickes, Cahall and Erie City
hoiilers the steam space available in
the top drum is advantageous both in
the capacity of receiver and separator.

The volume contained in the steam
piping between the boiler outlet and the
points of consumption helps a boiler
so far as its priming tendency is con-
cerned, providing proper drips are sup-
plied. This is principalh' on account
of its capacity and consequent receiver
effect. .\ well designed boiler should not,
however, be dependent upon the steam
line in order that it inay work success-
fully.

Water Space

It is not possible for the furnace of any
boiler to instantly respond to a sudden
demand for steam; consequently this is
automatically taken care of by a suffi-
cient drop in the steam pressure to evap-
orate the required additional amount from
the water contained by the boiler. Evi-
dently the greater the water capacity of
the boiler up to the normal water line,
the less will be the instantaneous drop
in pressure, due to a sudden increased
demand for steam, and the tendency of
the boiler to prime excessively or to
send slugs over into the steam line will
he decreased. The water capacity of

the drums of a longitudinal-drum type of
boiler is particularly effective in this
respect.

Many boiler waters contain impurities
which have a tendency to make the
boiler prime, especially at high rates of
driving, the compounds of sodium and
potassium being particularly troublesome.
Such impurities, however, do not cause
appreciable trouble until they have
reached a certain concentration in the
boiler. They do not leave the boiler with
the steam, but remain in solution in the
water and the longer the boiler is op-
erated without changing the water the
greater will be the concentration and
hence the priming tendency. It follows
then that, other things being equal, the
greater the water capacity of a boiler,
the longer it will operate under given
load conditions without priming.

Uniformity of Water Level

The water level of a water-tube boiler
when in operation may stand at approxi-
mately the same hight throughout the boil-
er or it may be at different bights, depend-
ing upon the design. Boilers con-
sisting of a bank of inclined tubes
terminating in front and rear head-
ers and the latter connected to
overhead longitudinal drums, will have a
single water level and this level will not
vary to any great extent with the output.
Boilers having a bank of inclined tubes
terminating in front and rear headers
with the latter connected to independent
cross drums, will have different water
levels in the front and rear drums when
the boiler is operating, the higher level
being in the front drum; the harder the
boiler is driven, the greater will be the
difference in the two water levels. Where
there are three banks of tubes terminat-
ing in three independent cross drums at
the top. there will be three different water
levels, the highest level existing in the
drum connected to the most active bank
of tubes.

The ability of a boiler to operate un-
der all conditions of load without prim-
ing excessively or sending quantities of
water into the steam line, depends to a
certain extent upon the steadiness of the
water level, especially at the most active
liberating surface. The level of the
water at this point varies with the out-
put and a sudden increase in the load
may raise the water level high enough
to cause serious priming. Conversely,
a sudden decrease in the boiler output
will cause the water level to drop in the
most active drum, this being' particularly
marked where the boiler is operating at a
large output and the generation of steam
is suddenly stopped by some furnace
trouble, such as the abrupt appearance
of large openings in the fuel bed, etc.
Under such conditions unless care is
taken, the fluctuation may exceed the
limits of the water column.

September 19. 1911

P O MC F. R

433

Ihrowing a Brick Stack

Bv A. D. Williams

The external wall began to crumple down
on itself and the firebrick lining projected
above the top carrving the tile coping.
In making room for a new bu.ld.ng ^j,^ ^^.^„ ^^ ,^^ downward side has
upon the property of the National Elec-
tric Lamp Association in Cleveland, it

became necessary to remove an old chim-

FiG. 1. CcniNC Notch to Csntek Li.nk
or Stack

ney which had been built for the Brush
Electric Company about 27 years ago. It
was decided to throw this chimne>. and
as there were dwelling houses about 20
feet from its base and about 50 feet
away at the side it was necessary to lay
it down in such a way as to avoid dam-
aging them. In this case it was neces-
sary to guard against all danger of the
stack kicking back and the nearest hous-e
was so close thai a screen was erected
to prevent its w indows from being broken.

Two holes were cut in the sides of the
chimney just in back of the center and
away from the direction in which it was
desired to fell the stack. Then a gap or
notch was cut in the side toward which
the chimney was to fall, the size of this
notch being increased until the load be-
came so great that the brick between the
previously cut holes and the notch
crushed. This process proved successful
and the stack fell exactly where it was
wanted.

The chimney was about fi feet square
■ '•idc at the bottom and about 4 feet
juare at the top and had an S-inch fire-
•ick lining separated from the exterior
wall bv a 2-inch air space. The red-brick
wall at the base was 17 inches thick,
about iiO feet high, and contained ap-
proximately ]n^.nrK) brick, weighing 305
tons.

Fig. 1 shows the chimney shortly be-
fore it started to fall with the men en-
larKing the notch which nearly reached
the center line of the stack. Fig. 2 shows
the chimney just after it started to fall.

started to break up in this illustration
and the base of the chimney appears to
have slid to the greund; this is shown
better in Fig. 3. where about half of
the lower portion of the stack is on the
ground and the top is still falling. The
firebrick lining projects nearly 20 feet
above the red brick.

1 he Opportunities of Muni-
cipal Ownership

The' value of municipal ownership is
set forth in a recent public address by
C. W. Koiner, manager of the municipal
lighting plant at Pasadena, Cal., a sub-
ject with which Mr. Koiner is thoroughly
familiar. The Pasadena plant is one of
the most successful in operation; it has
a 5-cent lighting rate and is said to net a
return of 1 1 per cent, on its investment.
He declares that the advantages of
municipal ownership- are really beyond
the comprehension of the average citi-
zen, and that people are just beginning
to realize its possibilities in the govern-
ing of all public utilities.

It has been demonstrated by a number
of municipalities scattered throughout the
United States. Mr. Koiner said, that when
a city is ready and wants municipal

a change in the employees and heads of
such departments, and the policy and man-
agement necessarily would be changed.
Municipal ownership will be successful
only in the cities where it is insisted that
all officers and heads of departments be
qualified for the offices they hold, Mr.

St.\ck Starting to Fall.

Koiner said. Coupled with this require-
ment, municipalities must expect to pay
their employees a liberal salary for the
sen'ice rendered, and unless a city is

V 1

( U P M' 1

ownership of any of its utilities il can
operate them and secure results in the
way of low rates and good serx'icc far
bcvnnd the expectations of the average
citizen No community which conducts
its affairs on a partizan basis can ever
be entirely successful in the operation
of any of its utilities, because with every '
change ol administration there would be

willing to give just compensation it can-
not hope to secure the type of employees
that il must necessarily have to conduct
Its public utilities. The utility corpora-
lions will take from the city. State or
nation its best men at higher salaries un-
less the public is villing to pay an equal
salary for the kind ol service it demands
and must have.

434 POWER September 19, 1911

Teaching Operating Engineering

The time was, and that not so many gy ] J\^ Pratt '^ ''""^ variable in its meaning, and i
„ „„„ tu„t riinnmo an pnpine was ' * requirements are not the same the coui

The time was, and that not so many
years ago, that running an engine was
regarded more or less as a laborer's job,
if a man could start and stop a ma-
chine, and have it in such a condition
that the crank would turn, he had ful-
filled about all the requirements, and no
one cared for or wanted anything more,
especially in the small plant. Today, the
man in charge of a single unit even, has
an opportunity, whether he embraces it or
not, to give evidence of ability. If you
talk with the average man running a
plant you will find in most cases that he
regards himself as efficient as is neces-
sary. It would not do him any good if
he did run the plant more economically,
he says, so he does not think it worth
while to get a full knowledge of his line
of work. To him I would say, get the
knowledge and condemn afterward, if he
wishes to do so.

There are three fundamentals to be
considered in studying the attitude of
such a man and the following questions
suggest these elements:

First: Is it because he has not had an
opportunity to obtain proper guidance
in the study of his work, that he is not
a master of it?

Second: Is it because he is too lazy
to keep himself always up to concert
pitch?

Third: Is it because he is asked to
work such long hours and so hard, in
such close, poorly ventilated engine
rooms, that no human being could be
at his best c.ny portion of the time, to
say nothing of all the time?

The men who have had the organiza-
tion of the Institute of Operating Engi-
neers at heart have been thinking of just
such questions as these, and it is the
purpose of its life to put the operating
engineer in such a place that he will be
recognized for what he ought to be, a
practical man, with lots of common sense
and a good education, worthy of just and
fair consideration and capable of pro-
ducing a handsome return on his pay as
an investment. Pretty close to the pro-
fessional do you say? Very well, let it
be such; then we have an operating en-
gineer in the full meaning of the term.

I am not planning to speak on any
of these questions except he one of
training the man, and not on the whole
of that. I will confine my remarks to that
which bears on the first steps — his ap-
prentice career, up to the time when he
can meet the requirements of a journey-
man machinery operator, as outlined by
the educational committee of the Institute
of Operating Engineers.

Relative to the lazy man. I will just
say that by some tneans he must get in-
spiration ; either by discipline or example,
and a correct view of life's great values.

Very few opportunities ex-
ist for a young man to
learn operating engineering
in a systematic and thor-
ough manner. The \\ il-
iamson Trade School trains
operating-engineering ap-
prentices in fundamental
principles and gives them
actual shop and power-
plant practice.

•Abstract of kxtiiio delivered at annual
meeting of the InfUilnte of Operating Engin-
eers, New York, September 1, 1911.

Briefiy, he must get for himself a prettier
and more wholesome picture of work.
With this I will leave the drone.

As to conditions of life, I wish to say
that if one considers the man behind the
power plant as nothing but an invest-
ment in cold hard cash, the best way to
get a high rate of interest on such in-
vestment is to put the man in such sur-
roundings, require such hours of work
and set him in such relation to the man-
agement, that he will feel like a maa
whose opinion is of value, and thus be
induced to work in such a way that he
will have opinions, and good ones at
that. You cannot get much of a return
from any person if you place him in
conditions such as you could not stand
yourself if you were holding his job. A
whole course of lectures could be de-
livered on the status of operating engi-
neering alone; but it would be manifestly
unwise for me to attempt to discuss this
as a topic when my principal theme is
another feature of the work, so I will
simply say that it is a paying invest-
ment when dealing with any man to do
as you would be done by — a golden rule
in more than the commonly accepted
sense. Reasonable hours, reasonable
time for recreation, reasonable dealing,
are things we must give if we expect
the largest return.

Up to the time when those who are
responsible for i.ie Institute of Operating
Engineers began its organization, the op-
portunity was very limited for a young
man to develop himself thoroughly by
following a regularly laid out and ar-
ranged course of work, by means of which,
when completed, he would receive recog-
nition as an engineer on the part of au-
thoritative persons, capable of passing on
his qualizcations. It is granted that
there was a license system, but a license

is quite variable in its meaning, and its
requirements are not the same the coun-
try over. The plan and scope of the In-
stitute, however, give an opportunity to
every person in the field who is willing
to work to become a well trained engi-
neer who will receive recognition of his
status, free from any influence of polity
or makeshifts of chance. His success
in gaining this station depends not sim-
ply on a set of questions, but on a rec-
ord of application to a purpose which
shows a tried and trustworthy man and
vouched for by parties well acquainted
with his work who are more capable than
himself, both as to theory and to applica-
lion in practice.

A point on which I feel that I ought to
touch is one relative to the so-phrased
machine-made engineer, of which one
hears at times. Machine-made, as in-
tended by those who use it, refers to a
man with a kind of exterior veneer but
with no real knowledge of the power
plant in practice. I would refer any who
entertain this idea to the pamphlet is-
sued by the Institute presenting the prac-
tical requirements of the apprenticeship
grades; he will find that before a young
man can become a journeyman machin-
ery operator, he must be able to do the
practical work around the plant in an
efficient manner.

The advantage which the young man
has in associating himself with the In-
stitute of Operating Engineers is not that
somebody will say he is an engineer when
he is not, but that, due to the careful
guidance which is at his service, he may
become an engineer much sooner than
would be possible without direction, as
he is not misusing his energy in trying
to study something which he cannot un-
derstand because of lack of preparation
or in spending his *:ime on work not di-
rectly applicable to his calling.

Some are expressing the fear that there
may be so many really good engineers
that pay will be materially reduced or,
to put it briefly, the field will be over-
crowded. This overcrowding of fields of
endeavor is so much of a sociological
problem, with the matters of form of
government, class relation and personal
initiative entering into it, that it cannot
be discussed in this paper; we may rest
assured, however, that just as iong as
we follow the good American plan of
letting every fellow rise just as high as
his ability will permit and do not allow
to develop the idea that because a boy's
father was a day laborer the boy, per-
force, can be nothing else, we need not
fear too many good men in any line.

I have alreadv mentioned the fact that
up to this time there has been verv little
in the way of an arranged guide for the
young man who wished to become an

September 19, 1911

POWER

435

operating engineer; such a one was left
largely to his own devices. But there
has been direction for the apprentice and
it may be interesting to know what were
the requirements for the beginning of
such work, the outline of the young man's
first steps in his trade, how he pro-
gressed, what he did and his recognized
status in the field after completing the
course. So I will present an outline of
the course that is offered at the William-
son Trade School.

The applicant must be at least 16 years
of age and is required to pass an ex-
amination in the following elementary
subjects: Reading and writing in English,
spelling, arithmetic, including weights
and measures, fractions and interest,
geography, .American history, composi-
tion and elementary English. This ex-
amination is not severely rigid, but a boy
must show reasonable proficiency in the
subjects mentioned before he may enter
on the course. His first year is devoted
to shop and academic work, spending
four hours a day in the class room and
four in the shop, with a half day off on
Saturday. The academic work is under a
teacher who gives attention to nothing
but class-room work, while the shop
work is under the instructors in machine
work and operative engineering. The
academic or purely school-room work
during this period embraces the follow-
ing subjects, in each of which the student
must satisfactorily qualify in order to re-
main at the school :

Arithmetic, grammar, geography, Amer-
ican history, reading, literature, physiol-
ogy and hygiene. In the shop during the
same period he covers the following
work, arranged in sequence for his proper
development: Plain chipping, using cape
and broad chisel. Use of steel stamps,
inside, outside and micrometer calipers,
general methods of laying out work,
lacing belts, reading speed indicators and
study of shafting layout. Flat filing
(crosscut and draw) work at forge in
cutting off, upsetting, fullering, flatting,
finishing and tempering. Soldering, sweat-
ing, use of threading dies, taps and rat-
cheting. Lathe operation, including cen-
tering, parting, facing, straight turning,
shouldering and chamfering, truing cen-
ters, filing, chuck work, right- and left-
hand thread cutting, taper turning and
fitting. Drill-press operating, including
reamer, tap and pipe work to layout,
countersinking and countcrboring, and
various methods of handling cylindrical
work. Shaper operation, including part-
ing, use of shoe or vise, down cutting
and surface work, cutting keyways and
planing to geometrical form as hexagonal
or octagonal work.

In reviewing this shop work if should
be kept in mind that the boy is taught;
he is not left to himself to get some kind
of a passable result which may have
been obtained by very poor methods, but
his teacher constantly visits him. giving

the points of nicety and refinement which,
after all, really classify the man as to
his quality in the trade. This same meth-
od holds throughout his whole course,
the aim on our part being to see. that the
boy knows what he is doing, why he does
it, and that his method is correct.

During the first year, the school-room
work takes place from 8 to 12 in the
morning and the shop work from 1 to 5
in the afternoon, class-room routine be-
ing the same as is customary in most
industrial schools, the class going for
a certain period to one teacher for gram-
mar, another for arithmetic, another for
history, etc. When entering the shop in
the afternoon, the class first goes to the
department class room, where after roll
call a shop talk is given, being one of a
series, which bears directly on the work-
ing features of the trade.

The general headings of shop talks
covered during the freshman year take
up the allied information necessary for
the successful handling of the work al-
ready presented under the shop headings.
The notes taken by the boy in these talks
are turned over once each week for in-
spection by the shop teacher, and their
completeness coupled with the appear-
ance determines a mark which goes as a
part of the apprentices' permanent record.

During the first year of hie apprentice-
ship the boy spends about two weeks in
the fire room, one day at a time, becom-
ing familiar with the room routine, parts
and general construction of the boiler and
the first elements of firing.

At the end of the first year the boy
begins to spend his entire shop period
in the power plant. He can now chip,
file, scrape, forge, babbitt, lay out and
can run a lathe, shaper and drill press
fairly well, so he is fit to start his study
of the purely operative side of the equip-
ment in an intelligent manner.

During the second year, the apprentice
will cover work involving the following
principles, and their application in prac-
tice: Classification of power-plant sup-
plies; systematic storing of supplies, cut-
ting, threading and general pipe fitting;
general electrical fitting, including splic-
ing, taping, soldering. light wiring, socket
and switch repairing and fitting, including
ceiling, wall and bracket work together
with bell work; handling of the boiler
accessories, including feed valves, gages,
surface and bottom blows, injectors,
safety valves, fusible plugs and draft
regulators; regular fire-room duty on
watch.

By such means the young man be-
comes well acquainted with general
power-plant conditions in their various
details, and is trained as a fireman. Dur-
ing this year his work is entirely under
the instructor in operative engineering.

As in the freshman year, a class-shop
talk is given each day by the instructor
on a subject bearing on the work being
covered, the outline of which is as fol-

lows: Care of power-plant machinery in
general; steam boilers; steam fitting;
general handling of electrical equipment.

The method of marking notes is the
same as has already been described.

The work in the academic department
during this second year is as follows:
Arithmetic, algebra, geometr>', chemistry,
physics, rhetoric, reading and literature.

During the last seven months of the
apprentice's work in the course, the boy's
time is eight hours a day in the power
plant, all academic work being done in
the evening during this period. This
academic work is in .the following
subjects: Geometry, trigonometry and
strength of materials. The shop talks
by the instructor in the power plant
carefully cover the subjects of steam,
electricity, heating and ventilation, pneu-
matics, refrigeration, gas engines and
producers, pumps and hydraulics, coupled
with calculations and the making of tests.

The principles covered by actual work
involve the upkeep of water-ser\'ice lines,
steam lines, care and operation of pumps,
both steam and motor driven, gasolene
engines, maintenance of battery equip-
ment, operation of the air compressor,
the handling of turbine and reciprocating
generating units and the running of re-
frigerating plants.

Each year all units in the plant are
tested under actual working conditions
for the purpose of determining economy
of operation. Such testing is covered as
an exercise by the senior apprentices,
each boy working out values and an-
alyzing diagrams.

It should be borne in mind that no boy
is held back or dismissed because he is
somewhat dull; in fact, there are a num-
ber of men who today are holding good
positions in power plants who would not
be so pleasantly located were it not for
patient and persevering teaching on some-
one's part when they were students.

As to the status of the young men
after finishing such a course, I will say
that most of them start in as assistants
on some phase of power-plant work, and
usually give reasonable satisfaction.

The advantage of a method of training
under direction and teaching is that at a
much earlier age an apprentice becomes
a more successful earner, hence a more
respected man and a better citizen, and
the policy of the Institute of Operating
Engineers in so carefully and thoroughly
planning along sue'' lines cannot but be
commended. It is sure to meet with ap-
proval and success, bringing benefit to
many and putting the operating engineer
on that plane in industrial work which
in all justice is his proper station.

With the use of petroleum by the" trans-
portation and manufacturing industries,
California has practically done away with
coal as a steam-raising fuel. Oil is also
used in that Slate in making gas em-
ployed, for cooking, heating and lighting.

436

P O >X' E R

September 19, 191 1

Hfut ]/().s.s Due t(i Huniitlity

B'l jdHN G. Moxtv

At first thought it would seem almost
incredible to state that the humidity of
the air has a marked effect on the eco-
nomic operation of a boiler; yet such is
the case and, what is more surprising,
w« may use up as much as 10 or 12
per cent, of the heating value of the coal
in just this way. By the term humidity,
of course, we mean the amount of mois-
ture present in the air as compared with
saturated air under similar conditions as
to pressure and temperature.

The amount of available heat used in
overcoming the humidity is that neces-
sary to raise the temperature of the
inoisture in the air from atmospheric
temperature to the boiling point, to evap-
orate it at that temperature and to super-
heat the steam thus formed to the flue-
gas temperature.

As an example we will take the data
from a recent test run on a certain 650-
horsepower water-tube boiler, using
lorced draft and burning semi-bitumi-
nous coal analyzing as follows:

ilvilicii.'iu i'..;!l i)er c-fnt.

0.\\ ;;vn 4.J1.' iicr icnt.

Siiliilinr .: l.Tn jn'i ii-m.

having a heating value of 1-1. 11)0 B.t.u.
per pound. The flue gas in this case
anahzed as follows:

rinlimi (licixidi- y.Mi )i»r i-.iir

(.'arlioii iiionnxidc i>.::o inr t-ciii.

11.52 X 0.792 + 34.56 ^0.0631 — °"°^"' j

-+- 4..(2 X 0.01(199 = 11.19 t^oiituii uj air
required per pound of coal.

Is it any wonder then that the ele-
ments are to be reckoned with in boiler
practice? With many blast furnaces we
already have methods of drying and heai-

I.O.S.SE.s IH-E TO EXOEl

.\iu .\xi> HrMiniTV

l'i;U t'K.VT.

i:.\cc-,,s .\ir

II

imiflity

E.ve.

.s.< .\ir

Ilumidit.v

EX<<SS \\T

Humirlity

IJ.I.U.

I'.r ( .1,1.

'.v!

2S2
■'■If,

■I . 00
1 6(1

2S2
226

2.00
1.6<J

(1

0

ir.n
I i:t.
:.(■.

I 20

II 111

169

11:1

.J6

0

1.20
O.WI
0.411
O.Oll

ID'J

.ias

2 HO

604

4.30

.NO

271

1 92

o37

:i.H|

60

L'o:j

141

469

3.33

I'O

40

fi6

i:i.-)

1 . .>>(!

0.96

401

2.S4

2(1

67

(1.47

333

2.36

(J

0

0.(10

266

1.S9

4(1

111

5:}3

237

3.7S

IBS

770

.-.46

10

' l.iS

1.12

691

4.90 .

-"

79 •

0 .i6

612

4.34

1 "

0

0 . 00

533

3.7S

10(1

! ini '

:; . 20

1250

S.S6

SO

.iBl

■1 .".«

1160

.•i.24

(iO

fiO

, !H1

l'71

.. IM'i

1 '.12

1070

7 . .■!''

4(1

ISO

1 2.S

979

6.94

2(1

'M\

II 64

S89

6.:i(i

"

"

0 (HI

799

5.66

100

."lOf.

3.60

1574

1 1 . l.v

NO

107

2.SS

1473

10.4.-.

.SO

6(1

1066

:iO.".

7 .".6

2.16

1371

9.71

4(1

2(i:-i

1 44

1269

S.9;i

2(1

102

0 7"'

116S

S 2.S

(1

II

II on

1066

7 . .-.»'.

100

.-.64

4 (Ml

1896

13 44

.so

4.i0

:M9

1782

12.6:1

Hill

6(1

i:i32

338

y 4.-1

2 4(1

1670

11..S4

w

211

226
11:5

1 60

II. so

1.558
144:.

11.04
10.24

"

0

II no

1332

9 . 4.-.

The accompanying table shows the
heat losses due to various atmospheric

60

70

<
CO 60

o

X

■^ 50

c

Q)

1

\ i ////yy

: ' .1

X/'//XA

1

1

; ///y//^^ i

1

fyyyy

I

' i ! ' yi/^/x//^

1 ////f^y \

\ v////y ■ '

.

V/0^ 1 !

////^ \

///^ \ \ ' 1

Per Cen-* Keat Loss 9,!^\r.

DiACK.\.M Showinc Loss Due to ExcErs Air and Hi/MiniTv

The amount of air theoretically re- conditions and various percentages of
quired to burn one pound of coal is excess air. The results were calculated
computed as follows: on the slide rule.

The curves show these results in
graphic form.

1..52C-|-,^4.5r.(// -j.')-t-4.^-

ing the air supplied, not only to reduce
the actual coal consumption but also
to give higher temperatures: it is there-
fore to be expected that in the near
future engiTieers in general will be di-
recting more time and attention to this
consideration and will install some
method to cut down this needless loss
just as we now have economizers and
feed-water heaters.

.\ Cn.sc of ()\ tTpre,s.siirt-
Bv J. E. Ter.man

Pat Casev was considered an old em-
ployee of the Red Bottle Distillei^- in
New Orleans, for he had been firing the
boilers for 10 years, and was the oldest
member of the force. Although he rarelv
drew a sober breath during his connec-
tion with the distillery, yet his constitu-
tion was such that he had never been
troubled with visions. When he spoke
concerning what he saw, it was believed
that something had actually occurred.

As everyone knows who is acquainted
with the New Orleans climate, it is
rarely cold enough there in the winter
to form ice. and such an occurrence as
the freezing of water pipes is almost un-
known. During February. 1899, however,
an exceedingly cold wave passed over the
countrx-. and the temperitture went down
to about 10 degrees above zero at New

September 19. 191 1

P O W F R

437

Orleans. On the coldest morning during
this unusual weather. Pat came to the
distillery very early to get up steam and
warm things up; he looked at the steam
gages and, finding that they registered
only 15 pounds pressure, he broke down
the fires, which had been banked the
night before, and started in.

Before long Emile Landry, the Creole
engineer, came in and began to busy him-
self about the engine room, packing a
gland or two and taking up the crank-pin
brasses. Landry had only been hired a
month previously when the old engineer
had run off down the street fighting an
imaginary pack of red and green mon-
keys. His excuse, when captured, was
that a big red one was sitting on the
throttle valve and bit his hands when he
attempted to shut down the engine.

Landry, who had heard of the antics
ot his predecessor, and had observed the
I'sual condition of the other members of
tht crew, had very little faith in any of
them. When Pat appeared at the engine-
room door on this particular morning
with a wild look in his eye, and yelled for
Landry to come to the boiler room as
No. 2 was about to burst, he was sure
that Pat had finallv succumbed to the
ii.tvitable, and was "seeing things."
Landry was a cautious fellow, however,
and thought that he had better look
around the boilers, and be sure that
everything was all right. Accordingly,
he stepped out to the fire room to take
a look at the gages. He was horrified
to find that the steam gage on No. 2
registered 245 pounds, while that on
No. 1 showed 55 pounds.

Pat. who had been dancing around the
room, suddenly had an inspiration.

"Faith. 1 will get on top of ther biler,"
ht said, "and aize up on the safet\ valve
and let the steam out."

Said Landry: "If you dare to go near
one of them safety valves, I will brain
yer with this fire hoe."

Landry began pulling the fire under
No. 2. and about 15 minutes later the
; ressurc had dropped to 40 pounds. He
' uld not account for the rapid fall in
I ressurc. but he considered it would be
-; fe to inspect the lever-type safety
\alve. To his surprise he found the
sr fety valve apparently free, and set for
the usual pressure of PO pounds. Hav-
ing looked everything over carefully he
told Pat to fire up again.

Pressure began to rise slowly and Pat
retired to the distillery to brace his shat-
ifred nerves. He tarried a while to tell
one of the crew nf his narrow escape,
and possibly 10 minutes elapsed before
he again returned to the boiler room.
One glance at the steam gage of No. 2
was sufficient for Pat. The pointer had
Just passed the last graduation on the
dial, rcgistcrinp .VKI pounds, and. with a
whoop. Pat bounded thrnueh the engine
room to the street, yelling to Landrv as

he passed. "Run fur > er life, Landry;
she is goin' up."

Landry was no coward, however, and
he felt that the safety of the plant and
that of the crew was in his hands. He
grabbed the fire hoe as he reached the
front of the boilers and began raking the
fire from under No. 2 boiler. In a short
time the pressure dropped again to 40
pounds. He decided not to take any
more chances until the boiler inspector
could be consulted, so he finally coaxed
Pat hack on the job to fix No. 1 while
he telephoned for the inspector.

Bill Grimes was the inspector in the
oftice at the time the message came, and
when he heard Landry say that No. 2 had
over 300 pounds on her. and to come

quick, Grimes replied: "Not by a d

sight will I come unless you get her cold.
I wouldn't go within 10 blocks of that

Cume down, and settling himself in the
fireman's seat he put the following ques-
tion to Landry and Casey:

"If 1 should connect a 6-inch pipe to
the steam header and connect a steam
gage to each end of it, then turn on the
steam, and one gage showed 80 pounds
pressure while the other one showed 300
pounds, what would \ou say was the
matter?"

Both Landry and Casey answered in
unison that one or both of the gages
would be wrong.

"Well, it's'funny." said Grimes, "that
the two of you together should have so
little sense that I must neglect real busi-
ness to come up here to coach you on
such questions."

"Do you mean." said Landry, "that
there wasn't 300 pounds on the gage of
No. 2 boiler?"

Pr E C'lNNEcrio.NS to Boilkrs

old kettle if she had I.^O pounds on her."
Landry assured him that there was
only 40 pounds on. and that it would
be considerably less by the time Grimes
arrived.

When Grimes reached the distillery.
Landry carefully described all the par-
ticulars; hoH he had examined the safely
valve and found it free, and how the sec-
ond time the boiler was fired the pres-
sure had run up to over 300 pounds
without blowing the safety valve. Grimes
was puz/led at first and questioned Lan-
drv closely as to how iranv drinks he
had t.-.ken that innrning. But Landry was
perfectly sober.

Grimes said he would go on fop of the
boilers and examine the safety valves
himself; but he really went to examine
the stop valves, to be sure that they were
both open, as they should be for regular
operation. Finding them all right he

"I didn't say so, did I?" replied
Grimes, "but if you will thaw out that
pipe by the window that connects the
gage of No. 2 and give the steam pres-
sure a chance to act on it, you will find
everything is all right."

The connection referred to ran by a
window at the side of the setting and
was frozen solid. As the gage and part
nf tht connecting pipe were close to the
breeching, the heat from the flue ex-
panded the water in the front end of the
pipe and gage so that the high pressure
was registered.

After things were running smoothly,
and Grimes had left. Pat said to Landry:
"Well, what d'ye think nf that, and me
almost skeered into signing the pledge!"

"Well." says Landrv, for the first time
since he had been on the job. "let's get
a drink. Casey." and they both hurried
into the distillery.

POWER

September 19, 1911

438 FUW tK septemoer ly, laii _ i

Potblyn, Pump Doctor

Br-r-r! "Hello!"
•'Hello! Is this Watson?"
"Yes."

"Well, this is Clark, at the Maddern
mill. We have one of your pumps over
here that is pounding infernal tar out of
itself."

"Impossible," I answered. "We don't
use any such material in our pumps and
if what you state is so it must be some-
thing that you have put into it since it
left here."

"Aw, quit your kidding. The facts are
that we have one of your 7'< and 5 by 6-
inch duplex outside-packed plungerpumps
feeding our boilers and the blamed thing
has given us a whole lot of trouble. The
plungers and the steam pistons get loose,
the plunger-rod keys break and we have
been ordering repairs and patching the
thing up until we are sick of it. I wish
you would come over and have a look
at it before we throw it into the scrap
heap."

"Well, Clark, I cannot understand why
the pump should act so. Is it handling
hot water?"
"Yes."

"Any head on the suction?"
"About 4 feet, I think; but come over
and see the thing for yourself."

"Can't now; I'm too busy," I answered.
"I'll send over a better man who will fix
you up if anybody can."

"All right, have him come right over.
Good by," and Clark hung up the re-
ceiver before I could say anything further.
I sent for Potblyn, gave him his in-
structions and thought no more of the
matter. About three-quarters of an hour
later the telephone rang again; Clark was
on the other end of the line and he was
hot.

"Say! Watson, I thought you were go-
ing to send someone over here who knew
something!"

"Yes," I replied, "I sent a man o\'er;
hasn't he got there yet?"

"Oh, yes, he's been here, but what the
dickens do you mean by sending a mutt
when I asked for a man to see what's
the matter with your danged old pump!"
"Couldn't he fix it?" I asked.
"Fix it? he would not even look at it
or take his coat off. He went into the
engine room, turned round once, said the
pump was all right and left. Don't you
suppose we know the circus we've had
with it the last six months? Something
has got to be done about it, and done
right quick, or it goes to the junk shop;
your company's reputation goes with it,
and we'll get a real pump from some-
body else; see!"

"All right," I answered; "you put on
the brakes and try to keep yourself from
exploding for a little while and I will see
what can be done." I turned to my work

By John Watson

The owner of the pump
felt sure the trouble was in
the pump itself. Potblyn
discovered it to be other-
wise, and incidentally met
an engineer whose style he
did not like.

and waited for Potblyn, for I knew that
as soon as he got back he would come
up to see me and probably have an in-
teresting story to tell that perhaps would
not quite agree with Clark's.

In a short time he came in and flopped
into a chair.

"Well, Doc?" said I. "Mr. Clark is
rather hot. He says that you never even
looked at the pump; that you said it
was all right and came away without any
explanation. Now tell me what is the
trouble and we will go over and see him."

"All right, Mr. Watson; I'll go over
with you if you say so, but if I do, they've
got to keep that man Johnson, their en-
gineer, out of the way or I'll make him
look like a small handful of small change.
I kept my hands off from him before, but
I don't think that I could do it again for
he's the worst loud-mouthed slob I ever
ran up against. As soon as I got in there
he began damnin' the pump and the
Blank Pump Works. Hs kept up such a
string of it that it made me sick, and I
ain't no chicken either. That darn fool
didn't know what he was talking about.

"He says I didn't look at the pump,
does he? Well, I did look at it, and it
took only one look to see what the trouble
was, and it wasn't with the pump either.
I'd have told him about it if he had been
anyway decent, but I just couldn't talk
to him so I came away.

"I can't stand these knockers! Most
engineers are good fellows and anxious
to learn any little kink and will try to
help a fellow all they can, but sometimes
you meet one that when he has trouble
in the place he spends his time 'knocking'
the machines. Usually those fellows know
very little, and the trouble is with some
of their connections instead of the ma-
chine. You can't tell 'em anything. Kick-
ing does not make an engineer, and this
man Johnson is no engineer; he's just a
plain ornery mule. I'll tell Mr. Clark
what's the matter if you say so, but if
there's too much Johnson, there'll be a
smash-up sure."

"Well, what is the matter. Doc; why
didn't vou examine the pump?" I asked.

"Didn't need to," he replied. "You see
it's this way; they've got an outside-

packed plunger pump for boiler feeding.
It handles red-hot water, and takes it
from a big tank or heater. There is about
4 feet head on the pump and a steam
pressure of about 4 pounds on the tank.
You would naturally think that there
would be no trouble in getting the water
to the pump. But that's the joker; they
don't always get water to the pump. Quite
a lot of make-up water is needed for
the system and they have a float in the
tank that operates to let in cold water
when the level falls. It lets this cold
water right into the steam in the upper
part of the tank. This condenses some
of the steam and reduces the pressure
and away goes the pump!"

"But what if it does condense some of
the steam. Doc; isn't there still some
pressure in the tank and four feet of
water head on the suction? That ought
to get water into the pump all right,"
said I.

"It looks like it," said Doc; "but it
don't do it. I've been up against this
same sort of thing lots of times and have
been looking for the answer, but never
saw anything printed about it. This is
how I dope it out: It is the same sort
of thing that you are up against on a
pump and receiver collecting hot-w^ater
drains and putting them back into the
boiler. You see, when pumping hot water
all of the time the castings of the pump
end get hot and are just about of the
same temperature as the water; there is
what I call a heat balance established.
Now, when you suddenly let cold water
into the receiver at the other end of the
line you put the system out of balance.
What happens? The pressure is low-
ered, the temperature of the water is re-
duced and the pump castings give up
some of their heat to the water in the
pulsation chambers and suction of the
pump. This is just enough to vaporize
some of the water, and all that the pump
gets is vapor; you know what happens
then. .Any pump under these conditions
will slap-bang some and produce just the
troubles that they've had over there. As
soon as I saw their hook-up I got more
interested in that than I did in the pump,
for I knew that it was dead wrong. I'll
bet a hundred dollars to a plugged nickel
that I can go over there and make that
pump slam to beat four of a kind; and I
won't touch anything about the pump
either."

"All right. Doc, let's go over and have
a look; I want to see you do it," I re-
plied.

We went over to the Maddern mills
and got Mr. Clark to go down into the
engine room with us. A little preliminary
explanation as to the trouble and the
attitude of his engineer led him to say a
few sharp words to that worthy, the sub-

September 19, 1911

POWER

439

stance of which meant "Shut up," and so
we were spared the chance of a mix-up
between Doc and the "engineer."

The pump was running as well as one
could wish; just a slow, steady stroke.

"Now watch her," said Doc. He went
over to the tank and manipulated the
float lever so as to let in a sudden supply
of cold water. He would certainly have
won the plugged nickel if we had bet,
for, sure enough, the pump started off
on a career of its own that promised to
lead speedily to destruction. Doc started
to e.\plain the matter to Mr. Clark, but
the latter did not care much about the
cause. He had become convinced
that the fault was elsewhere than in the
pump and his temper had cooled off until
it was back to normal.

"Well, now you have found out the
trouble," he said, "what can we do to
overcome it ?"

"It's a rather hard matter to wholly
overcome it," Doc answered. "You have
got to arrange to keep that suction sup-
ply as near an even temperature as you
can, for it is the sudden changes in that
which cause the trouble. If it was mine
I'd put a large vent pipe on that tank
instead of carrying a pressure. Then
condensation of the steam wouldn't make
such a reduction in the pressure. Fur-
thermore, I would arrange to take in the
cold water close to the pump instead of
into the vapor space of the tank; then
any disturbance of the heat balance
would send the flow of heat toward the
pump instead of away from it. Then I'd
take that engineer out and turn the hose
on him!"

With this parting advice we left. On
the way back to the works, Potblyn said :
"I don't feel wholly clear in my mind
about this business, Mr. Watson; I've
thought a lot about it and I've doped it
out the best I know how, as I've ex-
plained to you; but I'd like to know what
some of the other fellows think about it
and how they reason it out. I wish you
would write to Po\xer and ask if any of
the boys have had similar experiences
and how they got over them."

What do you say, fellows?

Most Pxoiioniical Aiiiourit

of CO.

By a. Bement

As there is much confusion of thought
on the significance of the CO. deter-
mination as applied to furnace fires, the
following may be of interest:

The principal difficulty appears to be
that sometimes CO: and efficiency real-
ized, in steam generation, do not cor-
respond; in other words, in some cases
the CO increases but the efficiency does
not. This fact has led to the use of
the expression "most economical point
of COj," based upon the assumption that
some point below the maximum might

be more economical. A recent committee
report stated that there is some unde-
finable relation between C0= and effi-
ciency that is controlled by some un-
known influence due possibly to the dif-
fering velocity of the gases in their
passage over the heating surface.

Combustion with the highest C0=
should in all cases give the highest effi-
ciency in steam generation. If it does
not, there is some counteracting influence
at work, because the higher the CO; the
higher the temperature of combustion,
and higher temperature produces greater
efficiency.

With many furnaces and methods of
firing there is often a more or less seri-
ous loss of undeveloped heat in hydro-
carbons which escape unburned, and
therefore it is practically impossible to
detect the presence of such hydrocar-
bons in the combustion gases by any
analytical process because of their small
volume. So it has come to be believed
by many that if there is no carbon mon-
oxide found, that combustion is complete

/I

^,

/

-—

N^

/

\

/

\

/

\

/

\

J

V

/

\y

fumaceConHnuoi/slyCMledi*'--No Coal Supplied— A

■< --1 >fe

■?"

->i

Hours "=«■■'

Diagram Showing Effects of Varia-
tions IN Furnace Operation

and hence that the significant components
are CO, and air, and that the control
of the combustion process is only a
matter of regulating the air supply. Thus
there is a belief that the amount of CO,
is sufficient in all instances, and if effi-
ciency does not increase with it, there
is a disposition to blame the CO, for
some supposed fault, when, in fact, such
demonstration should be accepted as
evidence that something else is wrong
which should be sought and remedied.
I have found it necessary in making
proper use of the CO, determination
first to produce a condition of uniformity
so that the CO, would remain constant,
and then to increase or decrease it by
increasing or decreasing the air supplied
or the quantity of fuel fed. If this is
done, the COj may be built up and the
maximum possibility of the furnace or
condition demonstrated.

If the mixing capacity of the furnace
Is ideal, it is possible to realize theo-
retical CO . With irregular firing or bad
stoker action, neither a high CO, nor
complete combustion is attainable. It
is, of course, true that if bad condi-
tions do prevail the "most economical"
amount of CO is a factor of importance,
but a remedy for such state is of much
greater value than a knowledge of what

is the most economical CO, under the
faulty condition.

The fundamental difficulty now is that
the significance of CO, in its relation
to excessive air supply is the only fea-
ture that has had much attention. The
other and almost as important one, that
of excessive or irregular fuel supply, is
neither understood nor properly ap-
preciated.

There are four features of importance
which may be considered as guiding
principles in the employment of CO2 de-
termination, as follows:

1. If CO: increases after the supply
of fuel or the reduction of draft, it shows
that air has been in excess.

2. If CO; falls, following the supply
of fuel, it shows that incomplete com-
bustion has been produced.

3. If the CO, is irregular and un-
even, it indicates a corresponding con-
dition of combustion.

•1. Assuming constant or uniform con-
dition of combustion, if impossible to
realize high CO,, it is an indication of
deficiency of the furnace in its ability
to secure good mixture of the gases.

The accompanying diagram may be
of interest as illustrating the matter
under discussion. During the first hour
coal was supplied, but none during the
second hour as designated. At the start
of the first hour CO, was low, about 5
per cent., due to excessive air, or in
other words, deficient fuel. Fuel was
then introduced at a regular but exces-
sive rate which brought the CO3 to 19,
after which, as the fuel supply con-
tinued, the CO, declined, due to incom-
plete combustion, which was caused by
this excessive fuel. When it had dropped
to 4 per cent, the coaling was discon-
tinued. Then the excess fuel burned
away gradually until the combustible and
air supply arrived again at a balance at
19. After this, owing to the fuel con-
tinually growing deficient, the CO:
dropped to about 6.

With this experiment, if the prevail-
ing conditions are considered in con-
nection with the amount of CO,, we learn
that during the first half of the first
hour, a decreasing excess of air caused
the rise in CO, and that during the sec-
ond half the fall was caused by the ex-
cess of fuel, which was necessarily ac-
companied by incomplete combustion.
With the first half of the second hour, a
rise in CO, was caused by decreasing the
fuel supply wNich arrived at a balance
with air at 19, after which, as no more
fuel was added, it dropped, due to in-
creasing the excess of air to about 5.5
per cent. The lesson taught by this
experiment may be applied to the gen-
eral use of the CO, determination.

It should be said in explanation that
the furnace used in this experiment was
a perfect one and produced an ideal
mixture, else if would have been im-
possible to secure so high COj.

440

P O \ii E R

September 19. 1911

Loose Piston Caused KiK)cks

About six months ago a knock was de-
tected in one of four vertical triple-ex-
pansion crank and flywheel pumping en-
gines. Nearly every day since then it
has been the duty of the engineer in
charge to try his hand at getting this
knock out of the engine, which occurred
in the low-pressure cylinder on the up-
ward stroke of the piston just as it
passed the top centers.

It was at first thought that the piston
was loose on the piston rod. The top
bonnets were therefore removed, but the
center-punch inarks on the nut and pis-
ton rod were still opposite. Nearly every
nut on the engine was tightened; tlic
piston-rod packing was found in good
condition: valve rods were lengthened
and \ arious amounts of compression were
tried. When given a great amount of
compression the knock shifted to the
crank end when the crank was at an
angle of about 10 degrees.

The cylinder was looked into again
and a wrench put on the nut holding the
piston in place and with a sledge the
center-punch marks moved about "s inch
apart. When the pump was started up
again the knock had disappeared. The
amount taken up b\- the tightening of
the nut was onl\- 0.013 of an inch.

Thowas H. Brock.man.

New Orleans. La.

How to Cut Packin;j;

Most engineers contend that packing
for steam or hot water should be cut
diagonally and not allow the ends to
touch when being fitted, hut experience
leads me to disagree.

If packing is cut obliquely, the ends
will ha\'e more of a tendencx to crowd
away from the rod than if cut square.
Furthermore, if the packing ring does
not touch at the ends, the expansion of
the packing is lost. When there is proper
expansion of the packing it will be
lengthwise of the stuffing box and the
gland may be loosened and the stuffing
box will really be fuller than when the
packing was first placed in it. Packing
which is cut short does not close the end
space by the expansion, especially pack-
ings containing canvas or cloth. The
spaces formed allow crosswise expan-
sion of the ring of packing adjoining,
and conseauenth- allows more or less
steam to pass.

R.\Y GiLBkRT.

Virginvillt, W. Va.

Practical

information from the.

man on the Job. A letter

dood enoudh to print

here will he paid foi^

Ideas, not mere words

wanted

Shock Absorber

Having read much about the destruc-
tive force of water hammer, I subinit the
accompanying illustration of a device
which would eliminate a great deal of
this trouble. The idea appears to be
almost too simple to be new.

If instead of an air chamber my

Pipe Fitting

SHfCK AnSORBI.H

cushioning dex'icc were attached to the
pump, there «ould always be a positive
cushion.

A fireman blows down his boiler and
recklessly turns the valve, thereby en-
dangering the lives of all about him.

With my device no harm could result
as the shock would be absorbed by the
spring.

H. Prew.

Montreal, Can.

It would seem that everyone should
be well infonned about pipe fitting, but
one often finds some strange and wonder-
ful arrangements. All piping should be
lun as direct as possible, avoiding un-
necessary bends and making the required
bends with a long radius where permis-
sible. If an elbow and valve must be
used an angle valve can take the place
of the two fittings, thus avoiding extra
pipe cutting. Elbows of 45 degrees should
be more commonly employed as they re-
duce pipe friction.

\'ahes with male instead of female
threads will often permit shorter con-
nections and will save nipples anJ fit-
ting besides having fewer leaky joints.
Do not put a pipe with a long thread into
a \alve; a pipe thread as long as the
thread in the nut on the valve is long
enough if screwed in full length; if
longer it will harm the valve.

In flanging pipe I have found that a
good tight job may be easily and quickly
made by heating the flange almost red
fiot and then quickly screwing it onto the
pipe without using bars or wrenches, and
cooling it off at once. Then cut off any
projecting thread flush with the face of
the flange and pull the pipe around the
face of the flange. I have flanges put
on a ti-inch pipe in this way that are
constantly under 300 pounds cold-
water pressure and they ha\e never
shown a leak.

Where there is room. I believe in
bending the pipe to make the necessary
■angles: with very little experience good
bends can be made by anyone. Where
the bends are nicely made the job looks
neater, has fewer joints in it to guard
against leakage, leaves the pipes to ex-
pand and contract more freely and
causes less friction. Piping up to about 1
inch can be bent cold: up to 4 inches it
can be easily bent by being first heated
in a forge and then bent by hand. For
larger pipes one needs a gas or gasolene
burner rigged up to go around the pipe
so that it may be heated as desired. Then
with one end of the pipe well anchored
and a good pair of chain blocks on the
other, one can bend any of the common
sizes. The most common trouble is the
buckling or flattening of the pipe while
trying to make short bends. Probably
a radius of seven times the diameter of
the pipe is as short as can be well bent
on standard pipe, but all heavy pipe will
stand shorter bends.

September 19. 1911

POWER

441

Do not try to spring pipes into place
if they do not fit. It will take less time
to take them out and will make a better
job.

Do not go at a job haphazard; think
it over before starting and if the job is
large or complicated it is better to take
careful measurements and make a draw-
ing of it before beginning: it will sim-
plify the work.

El)\XlN CoNKLIN.

Twin Buttes. Ariz.

Inexpensive He;iter

I have had very little hot-water re-
turns in summer, and as I did not care
to turn cold water into the boiler I made
a heater from a galvanized tank 12 feet
long, 4 feet wide and 20 inches high.
It was so set that the exhaust pipe en-
tered the end about ti inches from the
bottom. Fourteen 1-inch pipes were con-
nected at each end by manifolds, and a
float valve at the top keeps the tank
supplied with water. A I'j-inch pipe
was connected at the bottom for drain-
ing purposes when cleaning was neces-
sary.

The vacuum pump discharges into a
receiver which has an automatic throttle
valve for controlling the boiler-feed
pump. A ^i-inch pipe was nin from
the tank to the receiver, and by slightly
opening the valve from the tank I ob-
tained sufRcient water at about 190 de-
grees Fahrenheit, whereas before it did
not reach 80 degrees at any time.

In winter, when the heating system is
in use, I have more returns, therefore
more exhaust steam is used and less
goes through the tank, but I do not have
to use so much water and it has more
time to become heated. The total cost
of this heater was approximately •■^22.
Clarence W. Fashbaugh.
Fort Wayne, Ind

Cause of Hot Beariiij^s

If a bearing gets hot there must be

some reason for it, and it is up to the

•'gineer to find the cause and remove it.

The effect of dirty oil is to increase
friction as the grit will cause the metals
to wear quickly and cut in spots along the
bearing. This bearing will then heat
quickly.

Insufficient oil will increase friction be-
cause the film of oil between the rub-
bing surfaces is so diminished that the
:ctals come in contact and heat.

When a bearing is out of line with the

ift or the pin. the load will have to
supported by a portion of the bearing;

ic load per square inch will be greater;
this will force the film of oil out and
increase the friction. The heating will
be uniform at this point and intensify
with an increase of load. A cure can
Mtnetimes be efTected with pumiceslonc
and oil. white lead, sulphur and nil.

I have used pumiceslonc and oil to

good advantage, but these cures are used
where the difference in alinement is
slight. My method is to tighten the boxes
snugly, start the engine slow and feed
the pumiceslone and oil mixture through
a funnel 'to the bearing. Continue this
feeding until the bearing or boxes get
hot, hut not enough to run the metal.
The engine is then stopped and the
boxes are washed clean with coal oil.
The result is a finely polished pin and
box. If the variations arc too great, it will
he necessary to resort to scraping.

Vi'hen the boxes are too tight the heat-
ing will be gradual until the shaft has
sufficiently expanded to grip them, when
heat will be qi-ickly generated.

If the boxes are too loose a succession
of blows from the shaft or pin beat the
oil from the bearing surface and from
the metals making contact. A bearing
that is too small will become overloaded
at times, because the pressure per square
inch of surface will be great enough to
force the film of oil from between the
metals.

Light bearings have caused engineers
considerable worry. They may run nicely
when the load is light and heat up when
the load is increased. The only permanent
cure is to increase the area of bearing
or reduce the load.

H. R. Blkssing.

Philadelphia, Penn.

Boiler Room Repair

I used to have trouble with the through
rods leaking on an 18-foot b\ 72-inch
horizontal return-tubular boiler where
the rods pass through the front head, as
shown in Fig. 1.

These rods are held in place by a nut
and washer on the inside and the out-
side of the front head. It was the prac-
tice whenever the rods leaked to loosen
the outside nut and wind some asbestos
wicking around the rod between the
boiler head and the washer and then
draw up on the nut. This would hold

once a month, 1 had a curved lining
made, as shown in Fig. 2, This lining
has been in use for about seven months
and there is no sign of it again coming
down. When it does 1 intend to have
it replaced by an arch built of firebrick.

■JK-

Fig. 2. Curvkd Lining hok Top o.-
FiRE Door

thus doing away with the top iron lining.

I would be pleased to hear what suc-
cess the readers of Power have had with
this kind of arch.

H. B. Jahnke.

.Milwaukee. Wis.

Reiiiovinii; a Bctroni Cylinder
Head

Although it is on very rare occasions
that the bottom cylinder head of a ver-
tical engine has to be taken off, the time
does come when such a thing is neces-
sary.

Fig. 1. Rods Pass thriugh Front Head

tightly for a short time and then the
job had to be done over again. I de-
cided to try a 'A-inch sheet-copper
washer. It was put in place about five
months ago and there has been no sign
of a leak since. The copper washer was
made to fit lightly over the rod.

When the top fire-door lining came
down and the brickwork in the front
of the boiler had to he repaired about

How THE Cylinder Head \x as Re.moved

There are many designs of vertical
engines; hence, the methods which arc
used to do the work on some would n»t
answer the requirements of others.

The method described here can be
used on a number of differently designed
vertical engines. The sketch plainly
shows the idea. To use this method on
old engines would make necessary the
removal of four of the cylinder-head
studs at four opposite points; then they
would have to be replaced with four
longer studs of a suitable length to per-
mit the head to be lowered enough t*
enable the washers to gain easy access
to the cylinder. After the long studs
have been placed in position, four nuts
should be run on them until the nuts
touch the cylinder head. The head is

442

POWER

September 19, 1911

then lowered by unscrewing the four
nuts; here care should be taken to have
the head rest evenly on all of the nuts.

The four studs keep the head in posi-
tion and no difficulty is encountered with
the studs when replacing the head on
the cylinder.

G. E. Lambourn.

McKeesport, Penn.

A Rope Brake for Measuring
Power

The accompanying drawing shows a
form of absorption dynamometer I de-
vised and used for the measurement of
small powers at high rotative speeds. A
rope is placed over a pulley fixed to the
shaft the power of which is to be meas-
ured. One end of the rope is fastened
to a weight W, which rests on a plat-
form scales, as shown. The other end
is tied to a small pan to which weights
w may be added. In operation the
friction of the rope on the pulley tends
to raise W and, therefore, the platform
scales indicate less than this weight.
The amount of the force tending to lift
W obviously is the difference between
its weight and the number of pounds
recorded on the scales. The turning
eiTort of the shaft in foot-pounds is then

{W — P) r — w r,
in which

r is the radius to the center of the
rope in feet, and

P is the scale reading.

The horsepower is

2 B- (ir P — IB) rN

33,ooo ~

0.00019 (I^ ^ P — ^') ^
in which A^ is the number of revolutions
per minute.

Rope Brake and Scale

The turning effort may be controlled
by varying the weights w, a small ad-
dition to which will materially increase
the torque. An additional turn of the
rope about the pulley will accomplish
the same purpose.

This form of brake gives a very uni-
form resistance, there being practically
none of the chattering so common to
prony brakes, and it will give finer regu-
lation than that type of dynamometer.

It is superior to some of the other kinds
of rope brakes with which I am familiar
in that the stretch of the rope does not
affect the torque. Its simplicity of con-
struction will recommend it in cases
where it is desired to measure the power
of a small engine for a short time. It
seems likely, too, that it would be suit-
able for larger powers if provision were
made to prevent the rope from running
off the pulley and to keep it cool.

Julian C. Smallwood.
Syracuse, N. Y.

Pump Telltale

In a large power plant two large
boiler- feed pumps were set in the base-
ment of the boiler house. I found an
electrical telltale arrangement attached
to both pumps as shown on the accom-
panying illustration.

On the rocker arm on one side of the

Showing Contacts and Wiring

pump a contact piece was secured. At
two points on either side of the rocker
arm and at a distance within its reach
two other contact pieces were placed, as
shown. As the rocker arm swings, con-
tact is made with first one stationary
contact and- then the other. These con-
tacts light an incandescent lamp located
where the fireman may see it and he
knows that the pump which is out of
his sight is operating properly.

R. S. Wilhel.m.
Indianapolis, Ind.

Scotch Yoke for Steam En-
gines

Why is it that the Scotch yoke is not
used more on steam engines? It elim-
inates the effect of the angularity of the
crank rod and permits of equal valve
setting.

There must be reasons why the yoke is
not used in preference to crossheads and
crank rods. What are they?

Is the thrust upon the sliding surfaces
of an engine using the Scotch yoke
greater or less than it is on one employing
a connecting rod of average length?

Lloyd V. Beets.

Nashville, Tenn.

Piston Rod Swab

When I took charge of a certain plant
some years ago the engine had metallic
piston packing and required considerable
oil on the piston rod. I tried a swab-
holder which worked very well and made
quite a saving in oil. The holder is
shown herewith.

I took a piece of sheet copper and cut
a hole in it large enough to clear the

Swab Attached to Stuffing-box Gland

piston about 1/16 inch all around. The
outside of the holder is 1 inch wide and
is cut through on one side so that it
can be slipped over the piston rod. It
is bent at the top and bottom so that
it will clear the nuts on the gland. A
small hole is provided at the top of the
holder for a small pipe which leads from
the oil cup to the swab. The swab was
made of braided candle wick which fitted
tightly around the piston rod.

Before using this device it required
four cups of cylinder oil for a 10-hour
ran; with the swab one cup of oil is suf-
ficient.

Fred Langbein.

Port Clinton. O.

Efficiency Engineers

There is a growing class of individuals
who succeed in fooling some of the
people all the time. One of the latest
additions to this fraternity is the effi-
ciency engineer. When a plant is run-
ning along smoothly and paying a fair
dividend, along comes the efficiency en-
gineer. He ventures to suggest that he
can cut the losses in half in a week and
gets the contract. The process by which
the saving is to be effected rests with the
efficiency engineer. He is gifted with a
divine inspiration the moment he enters
the door which enables him to detect
leaks which others who have specialized
in power plants are unable to see. He
finds that the fireman fires too frequently
and admits too much cold air to the fires
or that the engine could be run with less
steam.

The owner, having hired this man. of
course, immediately upon reading the re-
port, suspects that his operating engineer
is inexperienced and incompetent and
that he has tolerated abuses which have
cost immense sums of money. The op-
erator finds it difficult to defend his posi-
tion. The owner, being a nontechnical
man, does not see the absurdity of the

September 19, 191 1

POWER

situation and readily believes, when the
appeal is made to his pocketbook. that
the recommendations are sound.

It must, of course, be acknowledged
that men who are experienced along cer-
tain lines are capable of correcting faults
in places with which they are not familiar.
Such men lend valuable service to both
the owner and the operating engineer
and their reputation is based on their
achievements, but there are few indeed
who are so broadly experienced that they
can apply themselves with equal effi-
ciency to all branches and successfully
institute valuable changes in al! sorts of
engineering establishments. The class
under consideration is composed of men
who pretend to do this and who create
false impressions and reap a good harvest
because of them.

Success depends largely on opportunity
and on ability, but principally on as-
surance. After all, the work is done by
the "man behind the gun" and there are
people who make a specialty of con-
structing guns. There are others who
are experienced in making the ammuni-
tion and the method of firing is taught
in the field. Just where does the straftger
fit who has never seen a gun and who
has never smelled powder?

Alfred Williamson.

Bronwille. N. Y.

Simple Enjj;ine Stop.s

The devices shown in this article may
help some young engineer to show his
employer what he can do in the making
of a safety stop for the old engine at
practically no cost. The stops shown
will give fair results in pipe sizes up to
3 inches in diameter; an old valve may
be used which has been discarded on
account of leakage, as a small leak will
not matter when the valve is used as a
safety stop.

In using an ordinary globe valve the
threads on the stem must be removed.
The valve shown in Fig. I works inde-

position it could be closed by removing
the ring from the pin, when the flow of
steam will close the disk. This can be
put in any handy place.

In Fig. 2 is shown a safety stop valve

7

rP^

Fig. 2. Valve in Horizontal Pipe

used on a horizontal pipe. The steam
is below the disk which is held open by
a weight independently of the steam
pressure. To close it, the ring on the cord
is pulled down and placed over the hook.

By reversing the position of the valve
the stem can be held in the open posi-
tion by placing the ring over the pin.

In Fig. 3 is shown an old idea slightly
changed as to design; it can be used with

Fig. 3. Valve Operated by a Wlicht

the steam pressure on either side of the
disk. A grooved wooden pulley is made
to fit on the valve stem upon which is
fastened a metal disk. A slot is cut out
of the flange which allows the stop F
to fit into it and hold the valve open.

Fitting Brasses

Recently 1 had to replace the wristpin
boxes on the high-pressure side of a 4200-
horsepower vertical, cross-compound en-
gine.

After starting up, the crank brasses
ran very warm and slacking them off did
no good. The engine was needed badly,
and it meant eight or ten hours' work to
again remove the brasses and pin.

Therefore we disconnected and plugged
the telescope oiler on the back of the
crosshead and in its stead put an im-
provised oiler in the duplicate hole in
the front of the pin. This oiler con-
sisted of a piece of 2-inch pipe about 10
inches long, and reduced to '.-inch pipe
screwed into an ell, which was connected
to the pin with a short nipple.

We then ground three cakes of Sapolio
into a fine powder, and mixed about half
a cupful to a gallon of cylinder oil, that
had been warmed enough to flow readily.
and fed it through the newly made oiler.
The engine was timed at about 15 revo-
lutions per minute, and in three hours
it was put up to speed, using its own
telescope oiler and oil system. It gave
no more trouble.

G. B. Gougstreet.

Somerville, Mass.

Hi teller Wages

As regards higher wages and more
strict license laws, I want to say that no
amount of legislation alone will make a
man fit to operate a power plant. He
must be trained to fill such a responsible
position.

More uptodate education and less leg-
islation is what is needed. If we make
good in the plant, the company will make
good in the pay envelop.

C. ,1. Wright.

.Alliance. O.

Diagram Advice Wanted

The accompanying diagrams were
taken from a Wheelock engine. I would

Fig. 1. Auxiliary Throttle Valve

. , . ^ ^ , , . . Distorted Diagram
pendcntly of the throttle valve. A clamp

B is secured to the steam pipe and a The handle on the cord is placed at any like to have some of the readers of Power
lever D is pivoted at the points C. To desired point. A pull on it will raise fell me what to do to remedy the appear-
close the valve in case of emergency pull the locking lever, which action will allow ancc of the crank-end diagram at admis-
fhe cord A and hook the ring over the the weight to descend to a slop shelf, slon and cutoff.

hook E. thus closing the valve. W. H Bi'LLARD.

If the valve were placed in a reverse Toronto, Can. .Iames E. Noble. Godcrich. Can.

P O ^JC• F, R

September 19. IP! 1

Sizes of I'urhiiif Steam and
Exhaust Pipes

With reference to Mr. Lotidon's re-
marks on the above subject in Power
for July 25, I would say that I agree
with much of what he says; and in my
first letter on Mr. London's curves
I Power, March 28 1, I mentioned that I
agreed that the curves were convenient
and would save much calculation. I con-
tend, however, as I contended then, that
the curves are not correct in two re-
spects:

Fi'-stly, for any sjiven weight of steam
per minute, the curves give the same size
of exhaust pipe for all terminal pres-
sures from atmosphere to 24 inches vac-
uum, the velocity in the pipe varying from
about 100 feet per second at atmospheric
pressure to about 400 feet per second at
24 inches vacuum. For vacua above 24
inches, however, the pipe is made to in-
crease in direct proportion to the specific
volume of the steam, so that the velocity
is always about 400 feet per second. This
is not, I hold, scientific, nor yet is it
correct from a commercial standpoint.
There is no reason — academic or com-
inercial — why an abrupt change of prac-
tice should take place at 24 inches vac-
uum. I believe that the velocity should
be gradually reduced from the highest
vacuum to atmospheric pressure; and the
diagram, without increasing its complica-
tion, could be altered to give this.

Secondly, the curves give the same
velocity for large-diameter as for small-
diameter pipes. I hold that this should
not be so, as the friction is less with
large than with sinal! pipes for the same
fluid velocity. A velocity varying accord-
ing to the size of the pipe could quite
well be allowed for in the diagram with-
out inaking it more complicated: all that
is required is to alter the positions of the
quadrants denoting the several diameters
of pipe.

These were, and are, my ppints. I
quite agree v.'nh .Mr. London that a for-
mula or diagram should not be excessively
complicated; and that it may be (and
usually is) impossible to allow for every-
thing; but we ought, I contend, to allow
for all important influencing factors, es-
pecially if these do not complicate the
formula or diagram.

As regards Mr. London's remarks about
the length of the exhaust pipe, this iriat-
ter has already been dealt with in iriy
last letter (Power, June 27). and, if a
bend be considered as equivalent to a

Comment,
criticism, suggestions
und debate upon various
articles. letters and edit-
orials which have ap-
peared in previous
issues

certain length of pipe, the same reason-
ing will apply to bends.

It will be obvious froin an inspection
of my formula and Mr. London's dia-
gram that the former could be put into
graphic form for circular pipes and would
be of exactly the same nature as is Mr.
London's, and in use would be neither
more nor less complicated.

R. M. Neilson.

Glasgow. Scotland.

Filling Oil Storage Tank

In answer to the request of W. W.
Warner in the .August 15 issue, I sub-
mit the accompanying illustration, show-
ing how acid was forced from the car
to the storage tank.

The outlet A was connected to the stor-

Mr. Poarclis Diagrams

In the August 22 number, Mr. Poarch
submitted a set of diagrams for criticism.
We received so many letters discussing
them that we are unable to print them
all in full. Therefore, we offer the
following synopses:

Mr. Hersey thinks that the cause of
the engine pounding is due to lack of
compression. . His opinion in regard to
the cause of the sloping exhaust line is
that there is some obstruction in the ex-
haust ports or in the pipe or that the
pipe is too small.

Mr. Knapp has the same point of view
as Mr. Hersey, but states further that
an excessively long exhaust pipe or one
with a large number of bends in it would
caus.e the sloping exhaust line. He be-
lieves that release takes place too late.
This should be made earlier, as should
also the point of compression by advanc-
ing the eccentric. Of course, this wilt
cause earlier admission too, but this may
be corrected by adjusting the link between
the wristplate and the valve crank. That
the expansion line does not fall below
the atmospheric line may be due to the
engine being overloaded.

.Mr. .Mason points out that with the

.Arrangement of Tank-car Inlkt and Outi>:t

age tank. The inlet B. used for filling
the car, was connected to an air com-
pressor. The compressor was then started,
thus forcing the air into the top of the
car. which in turn forced the acid out
of the car through outlet A.

Ib this manner the car was emptied
without bringing the acid into contact
with any pumping apparatus.

I have never tried this scheme with
nil. but I think it would work.

Charles G. Buder.

St. Louis. .Mo.

load remaining the same an increase in
the initial pressure would cause an
earlier cutoff and hence a lower ter-
minal pressure. The sloping exhaust line
indicates to .Mr. Mason that the exhaust
ports open too late and the pound indi-
cates that they also close too late. He
suggests advancing the eccentric, not for-
getting to adjust the steam valve after
so doing if the engine is of the single-
eccentric construction.

Mr. Cunningham writes that naturalV
if the engine runs satisfactorily noncon-

September 19, 1911

densing the valves must be reset in order
to get similar satisfaction when run-
ning condensing. He also suggests chang-
ing the eccentric to secure an earlier ex-
haust opening and point of compression.

Mr. Rockwell states that Mr. Poarch
must needs put on another eccentric so
as to have the exhaust valves separately
controlled, else when the single eccentric
is adjusted for sufficiently early release
the lead will be excessive. It is exces-
sive lead which in Mr. Rockwell's opinion
causes the pound when the engine is
running condensing.

Mr. Prescott in a careful analysis of
the diagrams reaches the same conclusion,
that the point of release should be ad-
vanced, also the point of compression.

Mr. Gagnier thinks that the diagrams
indicate leakage through the steam valves
or reevaporation in the cylinder. He sug-
gests checking up the diagrams by com-
paring them with an ideal diagram hav-
ing the same point of cutoff. Both Mr.
Gagnier and Mr. Dickson, whose letter
completes the number of letters received,
suggest earlier release and point of com-
pression.— [Editors.]

\'alue of CO.. Recorder

Recently I have read several articles
in Power about the value of the CO.
recorder. It seems to me that there is a
good deal to say on both sides of the
question. Certainly an accurate deter-
mination of the CO- in the stack gases
from a boiler, together with a record of
the temperature of the escaping gases,
will show whether the fuel is being
burned economically or not. High CO;
means low excess air; with low excess
air one is not using heat that should go
to the water to raise the temperature of
a large weight of cold air.

As for Mr. Vassar's statement that it is
not possible to get an average sample
by ordinary means, it has been my ex-
perience that with a 'j-inch pipe, closed
at the inner end and perforated with
1/16-inch holes extending across the last
, pass of the boiler, a couple of feet below
the breeching of the stack, uniform and
satisfactory results can be obtained. In
this connection I disagree with Mr. Uehl-
ing's statement that the ordinary method
of sampling by water displacement does
not give an average sample. Under ordi-
nary conditions, the variation in draft is
comparatively small. As for the varia-
tion in the flow of water, I am sure that
a measurement taken at the beginning
and at the end of a run would show an
error due to changes in the rate of flow
of the water less than the error of the
Orsat apparatus.

I believe that an analysis of the flue
gas is of value in showing whether the
fuel is being burned economically; that
a continuous record is better than an
average analysis, and that the sample can

POWER

be taken satisfactorily. The trouble with
the whole problem is this: Unless you
have laboratory conditions under which
to use your instrument, in addition to a
skilled man to apply the results obtained,
it is very difficult to obtain any results.
I have had some slight experience with
CO; recorders used in this vicinity, and it
has been my observation that, while they
were good enough in theory, practical
difficulties, both mechanical and those
due to the use of the available water,
caused them to be very uncertain in their
action.

J. F. MOWAT.
Joliet, 111.

445

The valve in seating carried by its proper
position so that steam leaked past the
back edges.

C. H. Chase.

Stoneham, Mass.

In reply to Mr. Uehling's letter in
the issue of August 15 on the value of
the COj recorder, I wish to quote two
of his statements, one from that letter
and the other from an earlier one by him
on the same subject. In separating these
statements from the context I do not feel
that Mr. Uehling is being treated un-
justly as the statements are quite definite
and are in no way modified by the con-
text.

June 13: "In all cases high or low
CO; means high or low efficiency "

August 15: "CO; by itself is not
claimed to be and, in the nature of things,
cannot be a measure of efficiency "

Enough said.

H. S. Vassar.

Bloomficid, N. J.

Mr. Fryant'.s Diajrrani

From a study of Mr. Fryant's dia-
gram, I believe that he will find that his
trouble lies in a leakage past the piston
as the first part of the expansion line
is almost parallel to the admission line.

The leak may be due to a bad cylinder
casting or a bad score in the cylinder
wall; if it is a score, it is only a short
one.

P. F. ROBNETT.

Kinmundy. 111.

The indicator diagram on page 256 of
the August 15 issue was probably taken
from a low-speed engine of the Corliss
type and at a very light load, the cutoff
being at about 5.5 per cent, of the stroke.
There appears to be a leak into the cyl-
inder past the steam valve as, for the
point of cutoff shown, the expansion line
holds up too much at the end of the
stroke, more than would be accounted
for by reijvaporation.

If the engine is blocked in its posi-
tion just after the start of the stroke, the
steam valve dropped shut and the corre-
sponding indicator cock left open, open-
ing the throttle valve will probably show
quite a blast of steam out of the indi-
cator cock.

The writer once took some similar dia-
grams from a Rollins engine which has a
gridiron cutoff valve on a vertical seat.

In regard to the diagram submitted by
Mr. Fryant in the August 15 issue, it is
my opinion that the trouble is due to a
partial closing of the valve as a result
of lost motion, probably between the
valve and valve stem.

H. W. Appleton.

Sturbridge, Mass.

Bleeding Receiver to Heat
Feed Water

Referring to the article in Power for
August 8, "Bleeding Receiver to Heat
Feed Water," the writer thinks the rea-
soning is somewhat misleading as the
statement is made that 903 B.t.u. would
be available for evaporation. The prin-
cipal medium for heating the feed water
is the latent heat of the steam, since it is
the condensing of the steam in the heater
which heats the feed water.

The latent heat of steam at 24 pounds
absolute is 953.5 B.t.u. Neglecting the
radiation losses, this is the amount of
heat which will be absorbed by the feed
water for every pound of steam con-
densed.

Another point to be considered is that in
order that the amount of work done by the
high-pressure cylinder may remain con-
stant the back pressure on this cylinder
must increase, since to admit more steam
the cutoff must take place later. This
means that the receiver pressure must
be increased and consequently the latent
heat of the receiver steam will be re-
duced. In order to predetermine what
the receiver pressure will be we would
have a complicated problem to solve.
There will probably not be much of an
error made when this rise in pressure is
neglected if we assume that only the
latent heat of the receiver steam goes to
increase the feed-water temperature.

If we assume that the engine will use
15 pounds of steam per indicated horse-
power per hour, it will require

15 V 670 = 10,050 pounds per hour
before the heater is installed.

Heat required to evaporate 25,500
pounds of water, or that needed for the
850.horsepower boiler, from a feed-water
temperature of 100 degrees to steam at
155 pounds absolute =
2.5,.S0O (IIfl4 — 67.97) = 28,713,756
B.t.u.

Of course, the condensed steam from
the heater would be trapped to the hot-
well. To simplify the problem we may
consider that the extra amount of con-
densation due to raising the feed wafer
to 210 degrees docs not mingle with the
feed wafer in the hotwell.

Let X — additional steam, which will
have to be admitted to the engine, and

446

let .V = steam condensed in the heater
to raise the feed water from 100 to 210
degrees.

If the engine is balanced, the steam
which is drawn from the receiver will
have done one-half of its work and

-v =r ■ .; y
The total amount of feed water which
must be raised from 100 to 210 degrees
will be

25,500 — .V — y
y is negative because this amount of con-
densed steam will have a temperature
due to the pressure in the receiver and,
therefore, will not have to have its tem-
perature raised. This is the reason why
it was assumed that y did not mingle
with the other water in the hotwell. Now
we have

(25,500 ^ X — y) ( 178 — 67.97) =
933.5y
Substituting the value for x in this equa-
tion and solving, we find x = 1391 and y
= 2782.

In order to admit this additional amount
of steam to the engine the cutoff must
be increased by about 14 per cent., neg-
lecting clearance, and it should be ascer-
tained whether or not this can be done
before it is decided to install a heater.
The heat given to the feed water equals
953.5 X 2782 z= 2,652.637 B.t.u.
Heat required to evaporate 1391
pounds of water from 210 degrees to
155 pounds absolute equals

1391 (1194 — 178) = 1.413,256
which means a saving of
2,652,637 — 1,413,256 - 1,239,381 B.t.u.

123.981
28,713,765

St. Louis, Mo.

^4.31 per cent.
George ^\. Peek.

We were much interested in reading
the article on "Bleeding Receiver to Heat
Feed Water" in the issue of .August 8,
because it recalls certain happenings of
long ago.

Twenty years ago. when the open-
heater business was young and the Web-
ster feed-water heater was one of the
thriving infants, power-plant owners were
hungry for anything that looked like
economy, but they were all "from Mis-
souri"— they had to be shown.

We remember one case, in a New Eng-
land mill. We tried to interest the me-
chanical engineer in our apparatus to
effect economy by heating his feed water.
We were told that it would be impos-
sible for us to aid him, for he was run-
ing the plant condensing, with a com-
pound engine, and could furnish no ex-
haust steam for an open heater.

Instead of being discouraged, our then
youthful spirit rose to the occasion and
"Necessity" became "the mother of in-
vention"— we needed that order.

POWER

We had theorized along the lines of
the article and felt sure that we could
save 4 or 5 per cent, of fuel, but we had
"doubting Thomases" to convince, and
the most convincing argument we used
was that we would take back our heater,
and pay for the piping changes, too, if
we failed.

The owner was perfectly willing to
pay our price if we made good.

We did not fail. The theoretical sav-
ings were amply borne out by the actual
results, and what to us was then a new
principle was established.

It seemed so novel that its inventor,
Warren Webster, applied for a patent;
but the Patent Office e.xaminers at first
refused it, on the ground that it was an
impracticable invention — something like
perpetual motion. When confronted, how-
ever, with actual proofs of success, the
patent was allowed.

^'e made use of the idea in a number
of suitable cases during the next decade
or so, and still use it. We are under
the impression that we were the first and
only ones to use it up till two years ago,
unless someone unwittingly infringed our
patents.

The patent expired about two years
ago, however, and the public is free to
use it. It is a good idea and our experi-
ence bears out your theory. The sav-
ings have amounted to from 3 to 6 per
cent., depending upon conditions.

Warren Webster & Co.
Camden, N. J.

Gat^e Glass and Water Level

In reply to a question by W. L. B. in
the issue of July 25, it was stated that a
gage glass in good order would show
the true water level in the boiler.

This is not exactly the case because
the water inside the boiler, being ex-
panded by the high temperature, is
balanced by a slightly lower column of
cooler water in the gage glass and its
connections.

This is easily demonstrated by blow-
ing out the water column until it be-
comes hot, when the water level will
be from ' :: to --i inch higher than when
the column was cool.

Rov W. Lyman.

Ware, Mass.

Gage Glasses

In the issue of August 8. Mr. Williams
refers to gage glasses and washers, and
says: "The washer should be placed in
the bottom of the nut." I would like
to have him explain a little more fully
what he means, as I am carrying high
pressure and have considerable trouble
with my gage glasses.

T. Bond.
San Diego, CaL

September 19, 1911

Making Corli,ss \'alve Gear
Noiseless

Having read C. R. McGahey's article
in the August 15 Power on silencing
valve gears, I tried the same stunt, drill-
ing holes in the crab claws and plug-
ging them with rawhide, but I got no
results. The crab claws were of steel
while his might have been bronze.

I have found the most successful way
to silence the ring in a steel crab claw
is to remove the case-hardened tail piece
and substitute black fiber tail pieces. The
black will wear much longer than the
red.

In ordering the fiber try to get it as
near the thickness of the steel tail piece
as possible. I usually make about a
dozen at a time, but a pair will last
from six to eight weeks on 36x42-inch
cylinders. Care should be taken in fit-
ting them or they will throw the cutoff
adjustments out. The surest way is to
apply the indicator after putting on a
new set, and the result is well worth the
trouble of renewing them every month.

H. J. MlSTELE.
.Milwaukee, '^"is.

Heat Units Required to Evap-
orate Moisture in Coal

Referring to Mr. Blumenstein's article
on "Heat Units Required to Evaporate
Moisture in Coal." there are two kinds of
moisture in a shipment of coal, namely,
moisture in "crystalline" form, which is
inherent with the coal when mined, and
the "surface moisture," which is entirely
superficial and becomes mixed with the
coal in washing, sometimes in transit dur-
ing rain and snow storms, and again by
sprinkling before firing.

The former, which may be from 0.5 to
25 per cent, of the total weight, is usu-
ally bought and paid for as coal. Fur-
thermore, this moisture reduces the evap-
oration both by cutting down the amount
of combustible and by heat being re-
quired to evaporate this moisture.

The surface moisture, which may vary
from zero to about 4 per cent, of the total
weight, is something that can, to a large
extent, be eliminated, and when contracts
are made it is well to have it stipulated
that the coal must not contain more than
a certain percentage of moisture.

In cinclusion it may be said that mois-
ture in coal is a dead loss to the consum-
er, and can in no way be made to help
out a contract where the cost of evapora-
tion and efficiency are at stake, unless it
be in that more imaginative way where
the hydrogen formed from the decompo-
sition of the moisture is made to yield
its heat to the water in "that more effi-
cient manner."

M. O. Horning.
Swissvale, Penn.

September 19, 1911

P O ^' E R

owcr

Bearini^ Pressures in Gas
Engines*

By G W. Lewis and A. G. Kessler

The accompanying charts and tables
show the average values of the maximum
bearing pressures in American stationary
gas engines as computed from data ob-
tained from the manufacturers.

Maximum Explosion Pressures in

Pounds per Square Inch of-

PisTON Face

Gasolene Engines

The average compression pressure of
gasolene stationary engines was found
to range from 60 to 75 pounds gage,
which gives a corresponding maximum ex-
plosion pressure of from 250 to 300
pounds per square inch.

Producer Gas Engines

In engines using producer gas (anthra-
cite), the compression pressure was
found to range from 90 to 175 pounds
gage, and the maximum explosion pres-
sure from 300 to 400 pounds.

Natural Gas Engines

For engines using natural gas, the com-
pression pressure varied from 80 to 150
pounds gage, and the maximum explo-
sion pressure from ,300 to 450 pounds
per square inch of piston face.

The above values were furnished by
manufacturers of the different types of
engines.

In the accompanying tables the bearing
pressures have been computed from ex-

•Copyrlghtpd. Iiy <;. W". I,.nls. liill.

12

.'. II

'?, 10
- 9

plosion pressures of 250, 300, 350 and
400 pounds, and on the assumption that
the explosion occurs when the crank is
at the head-end dead center.

Crank-shaft Bearing Pressure
Horizontal Single-cylinder Engines
From Chart I the average relation be-
tween the cylinder diameter and the
hearing diameter of the crank pin is de-
termined. From Chart 2 the bearing
length of the crank pin is determined in
terms of the bearing diameter. Using the
data obtained from Charts 1 and 2, Table
1 was computed; it gives the average
maximum unit bearing pressures for
cylinder diameters of 4, 8, 12, 16, and 20
inches, on the assumption of maximum
explosion pressures of 250, 300, 350 and
400 pounds per square inch of piston
face.

TABLE I. FOR HORIZONTAL ENdlXE.S

D

4

8

12

16

20

Assumed

Dcp

'i

3}

i\

6?

SJ iFrom chart 1

I.rp IJ

3J

H

6A

H

From chart 2

At

2.44

10.15

23.2

41.75

68

Dcp XI.<v = Acp

l'<n

-2..n-

.\ssumed

Key

1290

1240

12J(I

1210 U.'iii IKroni eiiuation A

Pv,

—300—

Assumed

Kn>

1550

14S.-. I4."i(l

1450

1390

From equation .\

I'm

—:!.->()—

•Assumed

At

l.soo

lT:ii)

1710

1 69(1

1
1(52(1 |l'roni equation .V

1

/'».

— 40(1 — ! Vssumed

At

2060

1980

I9.">0 1930

is.id From equation A

(vln

MU'h(

Acp
Mnii

ure in pounds per s<|uare nu-h of ptston face.
= Ht-iirwm 'li;ntici»'r of crank pin in inclies.
= Hiaruii; IriiKth of crank pin in inches.

- Maximum unit Iiearing pressure in pounds per square inch.
= Dnp Xt.rp, in sfpiare inches.
>rO«

(Drp xr.cp>

(A)

Hor

izonto

\ t

ng-

nes

>

\^

--'

'

^

"

•

r>

^

.=

'

^

^^

^

■-r"

'"

'»

^

*^:

I

')iai

ne

erC

'rai

}hl

''in-

■■0.<

^ID

■ai

>1

1^

r^

r

<^

12

V II

s:

c 10

8 10 12 14 16

Cylinder Diome+er, Inches

Chart I

~

Horizontal Engines

•

^

y

<

•<

L^

j>

^

f

'J^

r

oo

y^

r

^

Le

p;

ft"

^

^1.025 6 iam

efer Crank Pin \

^

y

■s^

_

3 4 5 6 7 8

Beorin3 Length Crank Pin, Inches

Chart 2

448

POWER

September 19. 1911

~

—

— \ — 1 — '■ ' 1

Vertical Engines

■^

^^

\ ! ^^^"'"''^

'

^

^

Y

u

L>

\^

^

■^

c

rar

k Pin

Oiamefer^OAl D

<

!r-

_

5 6 7 8 9 10 II 12 13 14 15 16 17 18 19 20 21 22
Cylinder Diameter, Inches

Chart 3

12
i> II

•S 10

c

i- 8

\ '

0 6

1 5

I ^

o 3
en

.5 2

I-

c I

(D I
CO

0

/ertical

^ -1

Enqines

^

^

^

^]

°\

^-1

.

^

^

o

.^

---'

"^

\

^

^

1 1

—

nS^

-^

0

Zrank Pin Leng'fh =

l.?ZCrankf

in Diam.-^

%>*

1 1

!

1 1

' 1

3 4-5678

Searing Length Crank Pin, Inches

Chart 4

Vertical Single- and Multiple-cylinder
Engines

Chart 3 gives the average relation be-
tween the cylinder diameter and the
cranl?-pin diameter. Chart 4 gives the
crank-pin diameter and the crank-pin
length for vertical engines. From these
Table 2 was computed, with the use of
the same cylinder sizes and explosion
pressures as in Table I.

Comparison of Pressures on Crank
Pins

The comparison of the average ma.\i-
mum units of bearing pressures on the
crank pins of vertical and horizontal en-
gines is best shown by Chart 5. As can
be seen, the pressures in the vertical en-
gines are considerably less than those in
the horizontal engines. In comparing the
tables, it also will be noted that the in-
crease of projected bearing area in the
vertical-engine crank pin is accomplished
by increasing the bearing length and not
the diameter of crank pin, as increasing
the latter would increase the circumfer-
ential speed.

The reason for making the unit bearing

T.4BLE II. FOR VERTICAL ENGINE.S

n

4

8

12

16

20

.\ssumed

Dcr

IS

3J

4i

6i

Sl'j

From chart 3

l-cp

Is

35

51

7f

91

From chart 4

Acp

2.64

lis

27.8

49 75

78.75

D<7. X/.tj>

P„i

— 250—

.Assumed

K,p

1190

1065

1035

1015

995

From equation .A

Pm

—300—

.Assumed

Kt

1430

1280

1240

1215

1200

From equation A

I ...

— .S30—

.Assumed

A'.v'

1660

1490

1440

1420

1400

From equation \

P,„

—400—

•Assumed

Kcp 1920 1720

1660

1620 1 1600

From equation .\

D =C,vlinder diameter in inches.

Pm = .Maximum explosion pressure in pounds per square inch of piston face.

Drp = Bearing diameter of crank pin in inches.

Lit = Bearing length of crank pin in inches.

A'pp = Maximum unit bearing pressure in pounds per square inch.

,4<j, =Dcp xLrji, in square inches.

2100
.2000
1900
1800
"l700
1600
1500
1400
1300
1200
11100
1000
900
800
700
600
500

R,

-li

^^

Ho

.1 1

r

1 1

1

1

— s

1 1

^/L.

^^

■~4-^

Pnl=J

>^=

Horizontal Engines

350 1 i

' — t — ^— ^i-- 1— L

"

-

^

!^

-

pj=jt=

^ 1

300 t<L

'7h~^--^ — ^— w — —

pH-4—

"7"^^

/ ' -1 '

r

vU —

=\

es

250 U

^

horizontal. Engines

^

-^

-i— ^

h-l-

Ver

tical

Engines

^-^

f

600

4-

c 500

\

^400

CL

w 300

\

\

\^

\

\

\,

„,.,

t 200

" Vertfc-

'-

1 1 1

tSdJpnfai ^■

_ — 1^ ' 1

I 100

^ III

1 1

\ 1 1

' 1

2 5 4 5 6 7 8 9 10 II re 13 14 15 Ife 17 18 19 20 21 22
Cylinder Diameter, Inches

Chart 5

20 40 60 80 100 120 \40 160
Brake Horsepower per Cylinder

Chart 6

ISO 200

September 19, 1911

POWER

1

Horizontal Engines

\

„

V

■^

^i-^

^

^

^

^

r. 'I

' °

^

A

<H

°

"

rA

-^A \

»

J

\A

k^

Main Bearing Diameter

J

iT .

\

6 7 8 9 10 11 IE 13 W 15 16 17 18 19 20 21 22
Cylinder Diameter, Inches

Chart 7

12
o il
-5 10

% '

^ 8
a>

E 7

D

5 6

fe 4
u

"^ 3

n
■5 2

I

0

Hori^onfal

cto

//7es

^

^

°

^

^

^

'^

^

K

H

"1

m!

F

»/o

'n Bearing Length

„

-S^

fZj Mam Bearing Diam. j

4 5 6 7 8 9 10 II 12 13 14 15 16 17 18 19 20
Bearing Length Main Journal. Inches

pressure less in vertical than in hori-
zontal engines is apparent from Chart
6, which shows the relation between the
revolutions per minute and the brake
horsepower.

Friction in Crank Pins
The work of friction in crank pins is
about the same for both vertical and
horizontal engines, as shown by the fol-
lowing tabulation, which is computed for
one case from the following data:

Horizontal \ertical
D —cylinder diam-
eter 12 inches 12 inches

D<r = diameter of

crank pin.. . . 4} inches 4 J inches
Ltp '^leneth of crank

pin 4} inches 5S inches

R.p.m 200 230

Maximum explosion

pressure 300 300 pounds per

square inch of
piston face
Mean pressure on pis-
ton 20 20 pounds per

square inch of
piston face
Maximum unit bear-
ing pressure 1450 1240 pounds

per square
mch
(X>i) Maximum unit

hearin;^ prei*sure. . . 98 81

(V) (-lirciimferenlial
speed in feet per

second 4 15 5 3

Work of friction V X

Km 407 429 f o o t-

pounds per
second

TABLE III, FOR HORIZONTAL ENGINES

D

4

8

,2

16

20

-Assumed

/r™i.

1.3

3.1

4.85

6.6

S.4

From chart 7

Lm,

2.6

6.75

10.8

14.9

19.1

From chart 8

Amb

3.4

20.9

52.5

98,5

160.5

DmSXii"*

P-

—250—

Assumed

K-A

462

300

270

255

244

Pm

—300—

Assumed

Kii

553

360

324

307

293

y™

—350—

.Assumed

Kmb

647

420

377

358

342

pm

— 400—

Asjumed

A'».6

738

503

430

408

391

D = Cylinder diameter in inches.
/>"» =Main hearing diameter in inches.
Lmb =Main bearing length in inches.
Amb — Projected area main bearing (one) = Di>* X t«*.

Pm = .Maximum explosion pressure in pounds per square inch of piston face.
A'"* —Maximum unit bearing pressure in pounds per square inch, on the assumption that explosic
occurs on the dead center.

r

y^

^

V

tri

'ca

Ertcii

nei

^

<\

y'

^

^

\

^

^

'

^

^

<^

^

^

>"

M

lin

Pri

jrin

gJBi'aji

TB/f

r

^

»>

-d

=^

-i

!

L_

8 10 12 14 16

Cylinder Oiometer, Inches

Chart 9

24

22

2 20

0 18
c

~ 16

i 14

1 12

■^'0

•! 8

S 6
oo

E 4

I 2

0

1

Vertical

En

gin

^

^

^

'

^

^

*-ir

'-'

A

°

^

-^

Ma,

i*f

•

::?

<*

=

ti.^

....,■. «s

Diameterl

0

1

Moin Bearing Diam

Chart 10

PO^yER

September 19, 1911

Average Maximum Unit Bearing Pres-
sure ON Main Bearings
Horizontal Single-cylinder Engines
Chart 7 gives the average relation
between the cylinder diameter and the

An Operator's View of the
Diesel Engine
By William F. Caton
Noticing considerable discussion lately

main-hearing diameter. Chart 8 shows of the Diesel engine from the standpoint

TABLE IV, FOR VERTICAL ENGINES

n

A

8

12

16

20

.\ssumed

DmJ,

u

3i

H '5

9J

From chart 9

Ln,h

3i

6}

10

13

16

From chart 10

.4 ml

5.25

23 , 6

55 1 or. 5

1 52

Dvih X Lwh

/'.«

—250^

.■\.ssumed

Kmh

:{i)i)

267

25.

2.5.'<

/'.«

-:„„,-

.\.s.-iimH,l

D = Cylinder diameter in inches.

Ihah = Bearing diameter of main bearing in inches.

I.mb = Bearing length of main bearing in inches.

Amb =/>)M6X/-«ft-

Pvt = Maximum explosion pressure in pounds per square inch of piston face.

as little trouble as any piece of power
machinery I have ever had anything to
do with. If all valves are kept tight
and the pistons and valves kept free
from carbon, the Diesel engine will work
like a clock from starting to stopping
time.

It seems to me, however, that the
builders have made a serious mistake
in advertising these engines to be able to
give good service with the cheapest of
help for operators. I have found that all
internal-combustion engines need just
as good mechanics to operate and main-
tain them successfully as do steam en-
gines.

The general run of operators claim that
the Diesel engine will work the best and
consume the least oil per unit of output
when working at about 75 per cent, of
the builder's rating, and I have noticed
that they will smoke when overloaded
or run on very light loads.

One very great operating advantage
about this engine is the absence of bat-
teries, magnetos and spark plugs to bother
with; these parts constitute one of the
great drawbacks of most internal-com-
bustion engines. A feature of the Diesel
engine which operators dislike, however,
is the splash lubrication, which makes
such hard work repairing bearings,
cranks, piston pins, etc. No matter how
thoroughly one tries to clean the parts in
the crank case there is always slush
dripping on your head and shoulders.

the relation between the main-bearing
length and the main-bearing diameter.
On the assumption that each of the two
main bearings takes one-half the explo-
sion load of the engines, and without the
flywheel weights, TaHe 3 was computed.
Vertical Single- and Multiple-cylinder

Engines
From Charts 9 and 10, Table 4 was com-
puted, showing the average maximum unit
bearing pressure on the main bearings
of vertical engines. In multiple-cyl-
inder engines, the outside or end bear-
ings next to the fiywheels are often made
considerably longer, from 1.5 to 1.75
times the lengths given in Table 4.

AvF.R.ikGE Maximum Unit Bearing Pres-
sure ON Piston or Wristpin

Horizontal Single-cylinder Engines
Table 5 was computed from data ob-
tained from curves giving the relations
between cylinder diameter, wristpin
diameter, and wristpin bearing length;
the relations are expressed in equations
B and C, Table 5.

Vertical Single- and Multi-cylinder
Table fi was computed in the same
manner as Table 5 from equations D and
E. These show the relations between av-
erage cylinder diameters, wristpin diam-
eters, and wristpin bearing lengths for
vertical engines.

TABLE V,

FOR HORIZONTAL ENGINES

D

4

S

12

16

211

D<rp

0.93

1 62

2 76

4.36

6 43

From equation B

L.rp

1.6

2.8

4 77

7.52

11.15

From equation C

An'

1.49

4.54

1 32

32 S

71.5

D-rrXLtr,

r«c

—250—

.Assumed

K,r,>

21011

276(1

i

2145

1530

lino !

]■.,:

-:mo-

Kr,.

25:f(i

1 .2:<n

2570

IS.O

1320

r„i

— :i50—

Assume.!

Kin>

2,.5„

1 .ss„

1
1

■iUOU

21.-,0

1540 [

P„,

— 100—

A.^sumed

AVp

3371)

1 125

1

3430

2455

1 760

D = Cylinder diameter in inches.

Dirp = Bearing diameter of piston pin in inches.

Ltcf = Bearing length of piston pin in inches.

Aap = Projected area of piston pin in square inches.

Pm = .Maximum unit explosion pressure.

Krcp = Maximum unit bearing pressure in pounds per square inch.

D<rp =0.0143 £)' + 0.7 inch. (B)

L-i-P =1.75 Dhv. (C)

of the operator, I am encouraged to put
forth a few points based on my own
experience. This type of engine gives

As this is true of all splash-lubricated
engines, however, it is not fair to con-
sider it as peculiar to the Diesel engine,

September 19, 1911

and I do not mean to intimate that it
should be so considered.

In a plant of six engines, driving gen-
erators which deliver a total of 900 kilo-
watts, I find that four men are required
to operate the engines, compressors and
switchboard.

I would like to see other operators
give their views regarding this type of
engine.

Power Transmission on Oil
Power Vessels

By John F. Wentvcorth
In the Power of August 15 there was
an editorial on this subject in which ideas
were expressed which differ far from
those which I have been working on for
a long time.

First, however, I wish to say that I
can see no legitimate excuse for the use
of gears between the propeller and the
driving engine. If my memory does not
fail me, the report of the British com-

POWER

cember, 1904. The ideas expressed at
that time were opposed by such men as
Lewis Nixon and numerous smaller lights
who stood out for the gas producer for
future achievements in the field of marine
engineering. The gas-producer vessel of
any size has yet to show up but the oil
engine, according to press reports, is now
being installed in vessels larger than the
one which I took for a concrete example
in 1904. Referring to the editorial of
August 15, I object to the charge that
"inherent lack of flexibility" is "char-
acteristic of all types of internal-com-
bustion engines." The Sargent gas en-
gine, in which the proportion of air to
fuel is kept constant, is flexible as far
as efficiency at all loads is concerned.
The use of an unnecessary amount of
air with the fuel is a cause of lessened
efficiency. If this "lack of inherent flex-
ibility" is meant to apply to the Diesel
engine I will heartily agree with Power.
It is in order to overcome some of the
major drawbacks of the Diesel engine

T.\BI.E VI.

FOR VEHTIC.^L ENT.INI

s

D

6

S

1..

16

20

D',

i;

li

2i

3J

4i

Equation I)

L-r

-i

3 J

44

61

s*

Equation K

A'f

4 67

6 33

1 1 2.-.

20 6.5

36 6

Cir,.X/..^;.

P-

1

-L.,-,„-

Assni)i«-d

At

,.„0

1990

2.i2<)

2 i.in

214.-.

/■-. — :((HP- \>siiiii.il

AV,.

IMM

JiiMl

:!iiL'ii

2..n

2,-,SO

/'-

— :i.-.(i-

\>.iimv.l

A-,.

,,„,

.■TM,

:(.■._'() •

:iliii

lidlll

/-

— 41)1)-

V"iirn,-il

A-,

1 ^'-'"

j iilW

w.w

asfin

.iUl) 1

451

needing 1000 horsepower, the motor must
be capable of 1000 horsepower, the gen-
erator over 1100 horsepower and the
oil engine not far from 1250 horsepower.
I should condemn such an arrangement
as inefficient and unnecessarily expen-
sive. It would in my opinion be far better
to rely upon air starting and revers-
ing than to go to such trouble and ex-
pense. On a vessel of any size at all
the saving would easily pay for the en-
gineer on watch to answer the bells, even
if the force could be reduced by the use
of the electric transmission gear. The
main disadvantage of relying on com-
pressed air is in the large bulk of air
needed to enable an engine of large size
to be manceuvered. There is also a pos-
sibility of the compressor going wrong
and crippling the plant. One of the points
I have been working on for the last few
years is to overcome this defect. Owing
to the patent situation, I do not fee! free
to give out details yet, but I ain working
on a substitute for compressed air which
shall be as positive as air, capable of
being stowed in a small fraction of the
space which the air at the same pres-
sure would take up, and more easily pre-
pared than compressed air.

An engine using crude oil for a fuel
and equipped with a method of govern-
ing similar to the Sargent principle as
applied to gas engines, coupled with
some compact means for stowage of
compressed air would to my mind leave
nothing to be desired in the marine-en-
gine line. If I do not succeed in meeting
these specifications, I hope someone will
be fortunate enough to solve this im-
portant and interesting problem. I do
not believe that it is necessary to har-
ness the oil engine to a generator in order
to secure a perfectly flexible and thor-
oughly reliable prime mover for vessels.

O =i'ylin(\*.'r rhanx'ter in inch<*s.

fjtf — Bearing diamt'ti-r of pi-.ton i)i7i.

/•■T - Bearing lenelh of piston pin.

A^ — Projected area of pLston pin in square inrhes.

A'"T —Maximum unit liearing pr»-ssure in pound.s per sqiiar<" inch.

I'm — Maximum unit explOM)on pressure.

Uw, - 0.fXJ7tt.j IJ'+ ii inches. (D)

/.., - 1.S2 Pt (El

-sion which met to pass upon the in-

..:allation of turbines in the "Mauretania"

and her sister ship reported that the

efficiency gain would be about one-tenth

• 1 per cent. With this slight gain all

'ts of mechanical contraptions are pro-
posed to enable the turbine to stay In the
marine field.

Now, coming to the engine question, I
wish to protest against Power's ideas on
the marine oil engine. I claim to be the
"orininal" marine oil-engine m*n. In
substantiation of this claim I refer the
reader to my article on the "Efficiency
of the Marine Oil Engine," which was
published in Marine Engineering of De-

that I have spent much time and money,
trying to produce an engine which shall
be the last word in the internal-combus-
tion engine. I hope before long to have
the opportunity to explain in detail some
of my ideas to the readers of Power and
to invite criticism and discussion.

Relative to the proposition to equip
vessels with an oil engine, a generator
and a motor. I fail to see the advantage.
The Diesel engine at best has an effi-
ciency of 30 per cent., and the mechan-
ical efficiency of the generator and motor
will be about 90 per cent, each, bringing
the overall efficiency down to about 24
per cent. In order to equip a vessel

[We cheerfully concede Mr. Went-
worth's claim to pioneering honors and
heartily wish that he may achieve the
fullest measure of success. But we can-
not withdraw the assertion that all in-
ternal-combustion engines are inherently
inflexible until he or someone else suc-
ceeds in building one that is not. Flex-
ibility, however, is a matter of speed
change and starling ability, not efficiency,
and we have yet to hear of a self-starting
gas or oil engine or one that accelerates
rapidiv with full load.

Mr. Wenfworth's criticism of the elec-
tric transmission is, of course, justified,
but the disadvantages which he cites are
well known and were referred to in our
editorial. The whole question reduces to
this: Is it better to continue using com-
pressed air for starting and put up with
inefficient propeller speeds and (soine-
limesi engine speeds, or to interpose
some form of flexible transmission be-
tween the engine and propeller and there-
by obtain both quick propeller control
and maximum propeller and engine ef-
ficiencies?- EniTOR.]

452

POWER

September 19, 1911

Water HaniDier i/i Steam Pipes

What causes water hammer in a
steam pipe? Explain the theory.

W. H. S.

Water hammer is caused by the
sudden arrest of plugs of water which
are got into rapid movement in the pipe
by conditions which bring about a differ-
ent pressure on the opposite sides of the
plug, as, for instance, when the plug
shuts off the communication between
the boiler and has boiler pressure on one
side and a reduced pressure due to con-
densation, the drawing off of the steam
or both upon the other.

Annular and Spur Gears
The pitch diameter of an annular gear
is 36 inches. The spur gear meshing
with it is 8 pitch and has 24 teeth. How
many revolutions must it make to turn
the annular gear 13 times?

B. C. H.
An 8-pitch gear with 24 teeth has a
pitch diameter of 3 inches and in one
revolution it will move the larger gear

A ^ _L of one revolution. To move
36 12

it through 13 revolutions the small gear
will have to revolve i^ =156 times.

J)ise/iarire Vemperature for
Ammonia

We have a 9'ix20-inch ammonia com-
pressor running 70 revolutions per min-
ute and the discharge pipe is so hot
that a drop of water put on it will boil
immediately. Is the pipe too hot and
does it hurt the ammonia?

T. L. D.

The proper discharge temperature for
an ammonia compressor operating be-
tween 15 and 185 pounds gage pressure
is about 250 degrees Fahrenheit. This
temperature is not too high for con-
tinuous operation. If desired, the tem-
perature of the discharge can be reduced
by slightly increasing the opening of the
expansion valves, so that a small amount
of liquid ammonia is returned to the
compressor.

Cross Compound Emriiie Valve
Setting
How are the valves set on a cross-
compound engine? I understand how to
do it with a simple engine.

C. A. L.
In a cross-compound engine the valves
are set for each cylinder as though they

Questions ar^

not answered unless

accompanied by the^

name and address of the

inquirer. This page is

for you when stuck-

use it

were on separate engines. If the valve gear
is direct, the eccentric will lead the crank
90 degrees plus enough to take up the
lap and lead. If the valve gear is in-
direct the eccentric will be 90 degrees
behind the crank, minus advance enough
to move the valve through the lap and
lead.

Safety VaPce and Grate Area

With 24 square feet of grate, burning
12 pounds of coal per hour on each
square foot and each pound of coal evap-
orating 10 pounds of water into steam at
100 pounds gage pressure, what area of
safety valve will be required?

H. D. H.
There would be burned

12 X 24 = 288 pounds
of coal per hour, and if each pound of
coal evaporated 10 pounds of water there
would be

288 X 10 = 2880 pounds
of steam made per hour or

3600

^ 0.8 pounds per second

The evaporation per square foot of grate

surface per second would be

0.8 ^ 24 = 0.033

Applying the Massachusetts formula for

the area of safety valves

, _W X 70 X II
--1 p

in which

A = Area of the valve in square

inches for each square foot of

grate surface;
W = Pounds of water evaporated per

second per square foot of

grate surface;
P = Absolute pressure per square

inch at which the valve is set

to blow.

0-o.^3 X 70 X II

115
0.22 X 24 = 5.28 square inches
of safety valve. The nearest commercial
size of valve will have a diameter of
3 inches.

Ce)itrifugal I'oree

How is the centrifugal force of a re-
volving body found?

A. J. L.

To find the centrifugal force exerted
by a revolving body multiply the weight
in pounds by 0.00017, by the diameter
in feet of the circle in which the body
revolves, and by the square of the num-
ber of revolutions per minute. The pro-
duct wmII be the centrifugal force in
pounds.

F/yii'/iee/ Diameter and Rim
Velocity

If the linear velocity of the rim of a
flywheel is limited to a mile a minute,
how many revolutions per minute are al-
low^able if the wheel is 9' 2 feet in diam-
eter?

B. H. C.

For a rim speed of a mile per minute
the number of revolutions is found by
dividing 1681 by the diameter of the
wheel in feet:

1681 , , ,.

= 176.0 re-coluitons

9-5

Wheel Diameter and Piston
Stroke

A locomotive is running at the rate of
50 miles per hour, the drivers are 6
feet in diameter and the linear velocity
of the crank pin is 24.44 feet per sec-
ond. What is the length of the stroke of
the piston?

L. O. S.

The stroke of the piston is equal to the
diameter of the circle made by the crank
pin. The diameter of the crank-pin circle
bears the same relation to the diameter
of the drive wheel that the velocity of
the crank-pin travel bears to the velocity
of the drive-wheel rim. The speed of the
drive-wheel rim is 73.33 feet per second
73.33:24.44: :6:2

Corrni[ated F/ue Collapsing
Pressure

Please give me a rule, not a formula,
for calculating the collapsing pressure of
a corrugated flue.

S. A. L.

Multiply the square of the thickness
of the tube in thirty-seconds of an inch
by 1200 and divide the product by the
greatest outside diameter in inches, multi-
plied by the length of the flue in inches.

September 19, 1911

P O W E R

453

Issued Weekly by the

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CIECVLATIOX STATEUEXT

Of this issue 31,000 copies are printed.

Hone sent free regularly, no returns from
neirs companies, no back numbers^ Figures
are lire, net eirculntinn.

Contents p

rrimlng of Water Tnlw Boilers

Throwing a Brick Stack

The Opportunities of Municipal Owner-
ship

Teaching Operating Engineering

Heat Loss Due to Humidity

A Case of Overpressure

I'otblyn. Pump Doctor

Most Economical Amount of COj

Practical I>etters :

Loose Piston Caused Knocks....

How to Cut Packing Shock Al>

sorber. . . . Pipe Kilting. . . . Inexpen-
sive Healer. .. .Cause of Hot Bear-
ings. .. .Boiler Koom Repair. .. .Re-
moving a Bottom Cylinder Head....
A Rope Brake for Measuring Power

Pump Ti'lltale. .. ..Scotch Yoke

for i^leam Kngln<-s. , . . Pisl<m R(m1
Swnl) .... EfHrlency Engineers ....

.Simple Engine Stops Kitting

Brasses. . . .Higher Wages .... TMa-

grnm Advice Wanted 4 10-

.' iisslfin I>etters :

»l7.es of Turbine Steam and Exhaust

Pipes miing on Storage Tank

....Mr. Ponrch's Dlagrnms. ... Val-
ue of Cf>j Recorder. .. .Mr. Kryant's
IMagrnm .... Bleeding Receiver to
Heat Keert Water ... .Oage (ilass
and Water Level. .. .Oage Tilasses
.... staking f'orliss Valve fiear
Nolneless. . . . Heal Knits Ref|iilred
In Evaporate Moisture In Coal... 444

Bearing Pressures In <;ns Engines

An ftiKTator's View of the Diesel Engine

Power Transmission of Oil Power Vessels

Editorials 4.1.1

Relative Costs of f*ontlnuonsly and Tn-
fermlltently Operated Refrigerating
Plants

Increasing Capacity of Compression
Plant

The Professlnnnl Kplrit

The Chief and the finremnr

Certificates of Quality

Examination questions furnish an ever-
ready topic for discussion whenever two
or more engineers meet. It frequently
happens that a candidate for a license
carries from the examination room the
memory of one or more questions which
he considers particularly unfair, and he
seeks sympathy from friends and ac-
quaintances. One feature of the examina-
tion is too frequently forgotten. This is
the application in which the candidate
states his total previous experience in
the operation of steam engines and boil-
ers. From this and the personal ap-
pearance of the man, the examiner must
form a very nearly correct idea of his
qualifications for the guarantee which the
State is asked to make before a single
question is put.

Engineers' licenses are not merely per-
mits to operate boilers and engines. They
are certificates that the holders are men
who have qualified for the positions they
seek. If a candidate lacking the neces-
sary practical experience is given a strict-
ly technical examination, he may be able
to answer every question correctly and
still be unfit. This is realized by the
examiner, who is the one really responsi-
ble for the man to whom he grants a
license, and he must ask questions that
are not to be found in books or published
lists. These are sometimes simple, as
was once the case with an applicant for
a first-class license: "Would it do any
hurt if the drop rod on a Corliss engine
was an inch too long?" asked the ex-
aminer. "Well. I should smile!" was the
reply. "If you were running a condensing
engine and lost the vacuum gage, how
would you regulate the injection water?"
was the next question. "I always feel
the overflow pipe whenever I go around.
I would go around a little oftener than
usual until I got a gage." This ended
that examination. His application had
given his experience and the two simple
questions evidenced his mental alertness.
These settled, the examiner had no hesi-
tation in certifying that the man was a
qualified engineer.

Another applicant was asked how the
cutoff on a Corliss engine could be
changed. He replied that it could be
done by altering the length of the rods
ninning from the governor to the valves.
This answer showed at once that he was
all adrift, and when the answer was fol-
lowed by the question: "Would not that
throw the governor out of adjustment?"

he was speechless. Had he been familiar
with the Corliss or any other type of
releasing gear, he would have said: "The
governor controls the cutoff; it varies
with the load and steam pressure, and
cannot be changed by the engineer."

If anyone should attempt to lengthen the
cutoff on a Corliss engine by changing the
length of the rods, the valves might ad-
mit steam enough to the cylinder with
the governor in its highest position to
cause the engine to run away under a
light load, and the man who would do
this should be debarred from the op-
portunity for trying it.

The Engineer's Opportunity

One has but to compare the plant of
twenty-five or thirty years ago with the
modern central station or the power plant
of a hotel or office building, in order to
appreciate the increased requirements as
to the qualifications of the operating en-
gineer. Formerly low-pressure steam was
used and as long as the plant ran satis-
factorily very little attention was paid to
the cost of operating it. Now, however,
the engineer must not only be well versed
in the principles of steam but he must
also be an expert on combustion and, in
many cases must have a general knowl-
edge of electricity, refrigeration, heating
and ventilating. Moreover, with the pres-
ent keen competition, he must be able to
produce results for the least cost. In
fact, the power plant may be considered
a factory for the manufacture of elec-
tricity or other forms of power and the
position of chief engineer corresponds to
that of the superintendent in any other
manufacturing establishment. His train-
ing must be as broad as that of the super-
intendent and should include a certain
amount of business ability as well as
technical knowledge; for not only must
he be able to direct the operation of the
engine room intelligently but he must
also be able to meet business men and
consulting engineers upon an equal foot-
ing. To attain this goal, however, re-
quires study and close application.

Like all other individuals, the operating
engineers may be divided info fhi^e
classes: those who have the "get there"
spirit and attain their objects in spite of
all obstacles; those who have a desire
to advance but do not know how to start
about it and lack the initiative to go
ahead single handed; and those who
lack ambition altogether and are ap-
parently content to leave conditions as

454

they are, thereby allowing the progres-
sive, energetic men to get all of the good
out of opportunities which they logically
ought to utilize.

Those belonging to the first class, al-
though ultimately attaining success, often
waste much time and energy in haphazard
efforts to discover what to study and
what not to study. The educational
courses of the Institute of Operating En-
gineers should prove of great benefit to
such men by placing at their disposal
the experience of others who have gone
through the same trials.

To the second class of individuals it
should be even more helpful, for not
only may it prove a guide to broad prac-
tical engineering knowledge, but it should
furnish an incentive toward the attain-
ment of such knowledge.

The third class may be dismissed with-
out further comment.

Mr. Pratt's article, in the present issue,
in describing the curriculum of the Wil-
liamson Trade School shows the good
work such schools are doing and indi-
cates the opportunities open to the youth
whose inclinations run to the operative
side of engineering.

POWER

deplorable part of American gas-pro-
ducer history made by the well meaning
but hasty people who thought a producer
was only a few sheet-iron tanks that
anybody could make. The design of a
good oil engine requires vastly more
preparation and experience than a fa-
miliarity with the simple forms of gas
engme, a smattering of machine design
and a textbook knowledge of the prop-
erties of liquid hydrocarbons.

Soft Water and Boiler Scale

The Oil Engine Fever

The internal-combustion engineers (no
misguided levity intended) appear to
have gone oil-engine mad. Everywhere
one turns, some engine builder is taking
up the manufacture of an oil engine, in
probably the majority of cases the Diesel
type. There are, of course, strong argu-
ments for the oil engine, no matter what
the type may be so long as the engine is
reliable and economical. The most potent
arguments are the absence of all appa-
ratus or machinery besides the engine
Itself, the fuel economy and the self-
firing feature. No boilers, producers,
heaters, scrubbers or other pieces of co-
operative or auxiliary apparatus; no
shoveling or wheeling of fuel and ashes;
no ignition apparatus to get out of order
at one or more of several dozen points;
no pressures to regulate; nothing to ad-
just or watch outside of the fuel, the
lubrication, the cooling water and the
moving parts of the engine. It sounds
too good to be true, and the actuality is
almost as alluring as the picture.

But, notwithstanding these obvious ad-
vantages, it is not quite clear why such
a wide-spread interest should be sud-
denly manifested in the building of oil
engines. Possibly the rapid development
of the Diesel and closely similar engines
in Europe has something to do with it;
the expiration ef the Diesel patents partly
explains the increased attention to that
type of engine aad its rapid progress
abroad.

Whatever the impetus behind the move-
ment may be, we do hope that the recent
and prospective additions to the list of
oil-engine builders will not parallel that

Where boiler-feed water is drawn
from ponds and streams its character
changes very materially with the sea-
sons. In a long dry spell the percentage
of dissolved solids is greatly increased,
while a spring thaw or a long continued
fall of rain has the opposite effect. Dur-
ing a dry period scale will form rapidly
because of the high percentage of solid
matter in the water. When the supply
from the springs is supplemented with
the water from melting snow, or surface
drainage during rains, its solvent capa-
city is greatly increased and it attacks
the scale already deposited in the boiler.
This It loosens from the shell and tubes
and the rapid circulation of the water
carries it along to regions more or less
quiet where it settles to the bottom.

These periods are particularly critical
in the case of horizontal tubular boilers
which are operated for a portion of the
day only and lie with banked fires the
remainder. So long as the circulation of
the water is rapid, the scale which comes
from the shell and tubes will not settle.
When the fire is banked the circulation
gradually ceases and the flakes of scale
go to the bottom. With the slower mo-
tion along the bottom of the boiler, a
few flakes are caught by the rivet heads
of the circumferential seam, others pile
up behind these and a bank is soon
formed, which the most rapid flow pos-
sible along the bottom of the boiler will
not dislodge.

Though the mass is somewhat open
and water will flow through it fast enough
to keep the sheet cool with light firing,
the intense heat which usually accom-
panies the putting of a boiler into regular
work evaporates the water faster than
it can find its way through it, and the
plate, softened by the heat, yields to
the pressure and a depression or bag,
as it is commonly called, is formed. As
the plate stretches the bank is more or
less broken, the water finds its way under
It. and the circulation distributes it
throughout the boiler.

So long as the circulation is rapid,
the depression in the sheet will not fill
with the traveling solids, but with the
first retardation in the flow, the process
of scale collection will begin again at
the same place.

Bags usually occur in the second
course lust back of the front circum-

September 19, 1911

ferential seam and are always caused
by the collection of scale loosened from
the tubes and shell by the combined in-
fluence of the soft water and the sweep-
ing effect of the circulation.

During the snow-melting period, or a
long continued wet spell, the surface
and bottom blowing should be frequent
and thorough, and the boiler should be
opened and cleaned more often than at
any other time. Not because scale forms
but because that already formed becomes'
dislodged and can collect where it will
do damage.

Taper Fits

From time to time there appear in
the papers descriptions of the panicular
methods adopted in removing a piston
or a crosshead from the end of a tapered
piston rod. In a drill-press spindle or a
lathe center, where provisions for fre-
quent and quick change must be made
and the tools for the work are always
at hand, the taper fit is both convenient
and proper. But on an engine or pump
rod. It IS a relic of the early days of inex-
perience in machine making that should
be abandoned.

Some engineers object to the use of
boiler cleaners which knock the scale
off from the outside of the tubes by
vibrating a hammer or knocker within
because they occasionally set tubes to
leaking. No tube which is in proper con-
dition will be made to leak bv the in-
telligent use of this tool. When scale has
been allowed to accumulate about the
tube ends and the tube sheet, overheat-
ing is liable to occur, and the removal
of the scale is quite likely to develop
a loose condition and expose a leak The
tubes should be given the reexpanding
which they need anyhow, and the cleaner
be given the credit of exposing their
loosened condition rather than blamed for
producing it.

It IS probable that within a short time
a new coal-saving scheme will be re-
ported and the same attempts to exploit
the purchaser that were so successful
three years ago will be repeated For
some twelve years an engineer on the
Boston & Albany railroad has been think-
ing over the problem of increasing the
heat value of coal by sprinkling it' with
some inexpensive solution. Considering
the problem solved, about a month ago
he began a series of experiments which
IS said to have shown the possibility of
saving, at a modest estimate, one-third
of the coal ordinarily burned in locomo-
tive boilers.

In 1910. California's oil production was
between sixty-five and seventv million
barrels. On the basis of three and one-
half barrels of oil for each ton of high-
grade coal, the oil production would
nearly equal twenty million tons of coal

September 19, 1911

P O \V E R

Relative Costs of Continuously

and Intermittently Operated

Refrigerating Plants

By Charles H. Herter

It is customary to run the refrigerating
machine in plants of 20 tons duty and
larger practically continuously through-
out the greater part of the year, while in
small plants, particularly in those of 10
tens duty and less per day, intermittent
operation is the rule, the small butcher
or produce merchant finding it more con-
venient and economical to shut down all
machinery at night. It will be necessary
to examine the factors influencing these
conditions of operation in order to decide
whether a given plant should be run 23
to 24 hours daily in summer, or only 8 to
14 hours.

A plant having a maximum capacity of
20 tons of refrigerating effect per 24
hours will first be analyzed, each ton
being equivalent to the cooling effect ob-
tained by the melting of 2000 pounds of
ice at 32 degrees Fahrenheit. As in melt-
ing I pound of ice at 32 degrees 144
B.t.u.* are liberated, one ton of refriger-
ation represents the abstraction of

2000 X 144 = 288,000 B.t.u.
this being the recognized unit for meas-
uring refrigeration. Besides represent-
ing the removal of a definite quantity of
heat, it also serves to express the rate at
»hich refrigeration is carried on, 12,000
B.t.u. per hour, or 200 B.t.u. per minute,
also amounting to one ton of refrigera-
tion.

Let it be assumed that the cold rooms
must be kept at about ,32 degrees Fahren-
heit, which temperature answers for the
majority of products stored, and figure
on ammonia-'"ompression machines as
this is the type most generally used. Also
count on expanding and evaporating the
ammonia in cooling pipes hung on the
walls or overhead coil bunkers of the
rooms; air circulation to be caused by the
temperature difference maintained be-
tween the cold pipes and surrounding air.
and not by a fan. because the advantages
accompanying the correct use of the lat-
ter are not as yet fully recognized in this
country.

The refrigeration produced by any am-
monia machine is governed by the quan-
tity of vapor formed; the more liquid
evaporated the more heat abstracted from
the surroundings. Referring to a table

'Koowo UK th>- Inf'iil Ik'HI nt fiiolon nt ic

Principles
and operation of
ice making and re
fri^eratin^ plantr
and machiner's

giving the properties of ammonia, it may
be found, for example, that to evaporate
1 pound of liquid anhydrous ammonia
under 15.(37 pounds gage pressure re-
quires that 555.5 B.t.u. I latent heat of
vaporization I be supplied by the air or
materials cooled, the temperature of the
resulting vapor being 0 degrees Fahren-
heit. The volume of this pound of vapor
is 9.028 cubic feet, and is to be pumped
away by the compressor. If the liquid
ammonia from the condenser reaches the
expansion or feed valve at a temperature
of 95 degrees Fahrenheit, and the aver-
age specific heat per degree in this range
is 1.14 (not 1, as formerly believed),

95 • 1.14 = 108.3 B.t.u.
are applied to first cooling the liquid
down to 0 degree; thus there are only

555.5 — 108.3 = 447.2 B.t.u.
per pound available for work, so that for
one ton of refrigeration it is necessary to
circulate

200 ^ 447.2 - 0.447 pound.
or 4.04 cubic feet of vapor per minute.
In case a temperature of, say, 12 degrees
Fahrenheit is desired in the heat-absorb-
ing pipes, evaporation must take place
under 25.43 pounds pressure, the net re-
frigeration available being

548.11 — (95 ^' 1.15) - 439 B.t.u.
per pound; and the amount of vapor re-
quired per ton,

2f>0 ^ , . ,

X (1.QJ4 = I.' S cubic jrri
4.V>

per minute. With a compressor of aver-
age quality the unavoidable losses will
not exceed 25 per cent., so that the pis-
ton displacement required per minute per
ton may be figured as follows: For 0
degree Fahrenheit,

- ■* = S.4 chI'v feci
cyn ■

and for 12 degrees Fahrenheit,

=1 4. J < uftlf jert

or 22.2 per cent, less than before.

The object of the above demonstration
is to prove that the refrigerating capa-

100 X

= 75-6 tons of work

city of a machine varies with the evapor-
ating temperature, and this again is gov-
erned by the suction pressure. Accord-
ingly the commercial capacity rating of
a machine is realized only under certain
definite conditions, and until a standard
has been universally adopted, these con-
ditions should be stated by the builder of
the machine. At present 15.67 pounds
suction pressure is being favored by
some makers because it corresponds with
the conditions usually prevailing in cold-
storage and ice-making plants. Others
adhere to 25 or 27 pounds, which pres-
sures are frequently used in breweries
where mechanical refrigeration was first
applied on a large scale. As may be seen
from the above, the "100-ton" machine
of the latter maker need only be 0.778, the
size of the other 100-ton machine, while
the respective prices asked are often
about equal. Approximately, the output
of a compressor varies as the absolute
suction pressure, a compressor rated and
capable of 100 tons refrigerating effect at
25.43 pounds gage being able, at 15.67
pounds gage, to do only
15.67 4- 147 .
2543 + 14-7

In the calculations to follow, use is
made of data published by manufac-
turers who tested horizontal double-acting
machines some years ago, their com-
mercial rated capacity being realized at
15.67 pounds gage suction pressure and
185 pounds gage condenser pressure.

To determine closely the probable
amount of refrigeration required in a
proposed installation is a very difficult
matter, as too many unknown factors
affect the result. The greatest uncer-
tainty exists in the quantity of goods to
be cooled and stored at different times;
therefore, the usual way is to estimate
all factors as closely as possible, and to
make an allowance for contingencies.

Whenever the manufacturer must guar-
antee to maintain specified temperatures,
he is compelled to figure the capacity of
his apparatus to suit the most severe
conditions occurring in summer, the ma-
chine necessarily running 24 hours per
day, so as to keep down the first cost;
but this time the advisability of installing
a machine which can do the work running
only about half time is being investi-
gated; thus it becomes necessary to take
into account all seasons of the year.

Tables published giving the average air
temperature in different cities do not in-
clude the temperature obtained in the
sun. In New York State this seems to

456

POWER

September 19, 1911

average 8 to 16 degrees above that in
the shade. Again, in the afternoon it is
about 9 degrees warmer in the shade than
it is in the morning. As only one-half
of the supposed building is exposed to
the sun, an effective temperature differ-
ence of

/8 + i6 \ , ,

{^-^ X 0.5 j + 9 = 1-5 (Irgrec!

between day and night can be assumed
throughout the year and taken as the
basis for Table 1.

TABLE I. AVERAGE

TEMPERATURES

FOB

THE

YEAR

Day

Nkiht

Season

Tem-

Differ-

Tem-

Differ-

pera-

ence

pera-

ence

ture,

from

ture,

from

Deg.

32

Deg.

32

F.

Deg.

F.

Deg.

Summer — June.

July, August. . . .

85

5.3

70

38

Autumn — Septem-

ber, October,

.^Jovember

70

38

55

23

Wintar— Decem-

ber, January,

February

40

8

25

—7

Spring — March,

April. May

60

28

45

13

Assume that it is desired to refrigerate
the three upper stories of a building,
50x100 feet, each 10 feet high, plus 1 foot
for ceiling thickness. The total storage
space is 150,000 cubic feet. To itemize the
quantity of fresh warm goods to be
cooled daily would lead to too much de-
tail. It will simply be assumed that the
requirements are, in summer, 12 tons of
refrigeration, or 3,456,000 B.t.u. in 24
hours; in autumn, 10 tons of refrigera-
tion, or 2,880,000 B.t.u., and in winter and
spring, 5 tons, or 1,440,000 B.t.u. The
other work of the refrigerating plant is
the maintenance of about 32 degrees tem-
perature in the rooms.

Figure on 43,124 cubic feet of air to
be renewed each day, for it is possible
to lose this amount through the opening
of doors; besides, such air change is
needed for hygienic reasons, and for cer-
tain products, such as meat, it ought to
be greater. The refrigeration involved in
this air cooling can be approximated as
follows:

One thousand cubic feet of dry air
cooled from 85 to 32 degrees requires

1000 X S3 y 0.019 = 1007 B.t.u.

One thousand cubic feet of air at 85
degrees and 60 per cent, relative humidity
contains 7642 grains of moisture; at 32
degrees and 70 per cent., 1479 grains.
The amount to be condensed equals 6163
grains, which divided by 7000 equals
0.88 pound. This multiplied by the latent
heat, or 1072 B.t.u. equals 943.3. To cool
the condensed vapor takes

Lh. Deg. F. Sp.Ht.

0.88 X (85 - 32) X 1 = 46.6
To congeal the condensation on the pipes
at 32 degrees takes

Lh. B.t.u.
0.88 X 144 = 126.7

To cool the ice on pipes to, say, 12 de-
grees takes

Lb. Deg. F. Sp.IIt.

0.88 X (32 — 12) X o.,5 = 8.8

Total per 1000 cubic feet =2132.4 B.t.u.
For 43,124 cubic feet it would require
91,957 B.t.u., or dividing by 53, 1735
B.t.u. per degree temperature difference
between that of the rooms and the
atmosphere. At smaller differences
the work per degree drop will really
be less than this, because the moisture
content decreases; but this may be
neglected, for the above amount of air
change is taken arbitrarily.

For completeness an allowance can
also be made for the equivalent of two
men working in the rooms 10 hours in the
day time in summer and autumn. They
will emit two pounds of moisture, which
item will add to the work, by the above,
2 1, p. 4 — 1007

2 X

0.88

= 2560 B.t.u.

They also emit heat, which at 32 degrees
Fahrenheit has been found by test to
amount to

2 X 600 X 10 = 12,000 B.t.u.
Sixteen-candlepower incandescent lamps
radiate 165 B.t.u. per hour; twice this
much, or 330 B.t.u., when old. Six lamps
burning 10 hours may, therefore, radiate
19,800 B.t.u. Total for men and lamps.

In autumn the total loss in the daytime
amounts to 897,750 B.t.u., and at night
to 543,375 B.t.u.

In winter a loss of 189,000 B.t.u. dur-
ing the day is estimated, and a negative
loss or gain of 165,375 B.t.u. during the
night, leaving a net heat loss per day of
24 hours of 23,625 B.t.u.

In spring the day figures are 661,500
B.t.u., and the loss at night 307,125 B.t.u.

In reality it is not possible to so dis-
tinctly separate the heat losses of day
and night, because it is the actual tem-
perature of the two sides of a wall, not
of the air in contact with them, that de-
termines the heat transmission. The
temperature of the wall follows that of
the air only very slowly.

In Table 2 the average for the year is
12.26 tons refrigeration per day, or 61.6
per cent, of the maximum load. In sum-
mer one ton of refrigeration takes care
of 7540 cubic feet of storage space. In
the table the night work is not computed
separately, because cooling of goods is
not limited to day time only, the work of
the machine being kept practically con-
stant during the hours of running.

Excluding the cooling of fresh goods,
the work to be done throughout the year
fluctuates in this 20-ton plant, the 10-ton
plant to follow, and probably in other
similarly proportioned and exposed
plants, about as follows:

TABLE 2. TOTAL REFRIGERATION REQUIRED IN 20-TON PLANT

Season

Summer % ^

I
.\utumn f

Winter . f

J^pring (

1,440,000
5 tons

1,440,000
5 tons

Heat Loss

Air
Renewal

Men and
Lights

2,149,875
-1-7.9 = 19

91,957
9 tons

34,360

1,441,125
-(-5.36=15

65,9,30
.36 tons

34,360

23,625
4-0.19 = 5.

13,880
19 tons

17,180

968,625
+ 3.59 = 8.

48,580
59 tons

17,180

5,732,192
4,421,415
1,494,685
2,474,385

34,360 B.t.u. For winter and spring only
one-half of this will be allowed.

Next the amount of heat entering the
building must be calculated. Let the in-
sulation be such that heat cannot leak
through the walls and floor at a greater
rate than 2.5 B.t.u. per square foot per
24 hours per degree difference; and
through the roof at the rate of 2 B.t.u.;
that is, 1 B.t.u. per 12 hours.

Sq.Ft.

Area of floor is 50 X 100 = 5,000

Area of four walls =300 X 33 = 9,900

Total 14.900

Area of roof 5,000

In summer the heat leaking into the
building averages during the daytime,

B.l.u.

14,900 X 1.25 B.l.u. X (85—32 degrees) = 987,125
Througli the roof,

5000 XIX (85 — 32 degrees) = 265,000

Total, 1,252,125

At night the leakage is

14,900X1.25 B.t.u. X (70— 32 degrees) = 707,750
5000 X1X(70— 32 degrees) = 190,000

Total, 897,750

Percent.

Summer 100

.\utuinn 67.8

Winter 2.4

Spring 45 . 5

.■Average for the year 53.9

Without such an analysis, figuring as
usual on the summer duty alone, and
knowing that the plant can be arranged
to do all the work then in 12 hours, the
installation of a 40-ton machine looks
justifiable. With the analysis before us,
however, it will be seen at once that the
20-ton machine is bound to be more eco-
nomical even though it must be run 24
hours daily in summer. In autumn it will
have to be run only 18' c hours; in
spring, 10'4 hours, and in winter 6'4
hours. With a 40-ton machine operating
for only half of this time, the cost would
be decidedly greater, the piping required
would be double, and the whole appar-
atus, being idle for such a great portion
of time, the total cost of operation and
maintenance would greatly exceed the
cost realized with the 20-ton machine.

September 19. 1911

POWER

457

While according to the above, a plant
doing its 20 or more tons of work in 12
hours in summer is likely to be uneco-
nomical, many plants of 10 tons and less
capacity are so arranged that they can do
their work in 12 hours, without the cost
of operation being increased. This ap-
plies especially where motive power other
than steam is used and a licensed engi-
neer is not required, one operator being
able to handle the whole plant alone.

Take, for instance, a building with
three floors 30x74.2 feet, each 9 feet
high, plus 1 foot for ceiling thickness,
the storage space aggregating 60.000
cubic feet, and the temperature 32 de-
grees Fahrenheit. Figure on cooling
fresh goods daily at the rate of 4.5 tons
refrigeration in summer, 3.5 tons in
autumn, and 2.5 tons in winter and
spring. Using the other figures from the
estimate on the 20-ton plant, an ar-
bitrar>- air change of, say. 34.499 cubic
feet per day, will require 73,566 B.t.u.

Dividing by 53, the difference in tem-
perature, gives 1388 per degree tempera-
ture difference.

The heat introduced by men and lights
would be 34,360 B.t.u., and the insula-
tion used allows 3 B.t.u. to pass per
square foot per degree temperature dif-
ference per 24 hours.

Area of floor, sq.ft 2,226

Area of roof, soft 2.226

Ana of four walls, sq.ft 6,252

Total, sq.ft 10,704

Then,

10,704 X 1.5 = 16,056 B.t.u.
per degree difference per 12 hours. The
average amount of heat leaking into the
building is given in the following table:

Season

Day, B.t.u.

.N'ight, B.t.u.

Summer

Autumn

Winter

8.5n.96S

fiin.i2S

+ 12«.448

Net loss par

449..i6S

610,128
.369.288

flprinir

fia.v. 16.0.16
208.728

In Table 3 the average capacity for the
year is 6.2 tons of refrigeration per day,
or 62.3 per cent, of the maximum load.

in conjunction with ample piping, so that
this small machine during summer can
do the work in nearly the same running
time as a 20-ton machine working on a
lesser number of feet of pipe.

At 20 degrees temperature difference
between the ammonia vapor in the pipe
and the air circulating in the room, it can
be figured that 1 lineal foot of 2-inch pipe
will abstract heat at the rate of
B.t.u. Deg. F.
1.6 X ;!o = 32 B.t.-u.
per hour, or 768 B.t.u. per 24 hours.
This means

: 88,000
768

= 375 li'tcol jeet

of 2-inch expansion pipe per ton of re-
frigeration. If the gas in the cooling
pipes is in a dry state, this heat-trans-
mission coefficient k may be as much as
33 per cent, less, while with wet vapor it
may be 33 per cent, greater. The coeffi-
cient declines rapidly as the temperature
difference decreases, owing to the cor-
responding reduction in speed of air cir-
culation, and is not likely to improve at
differences exceeding 20 degrees unless
there is forced air circulation. With 16
degrees difference, k may be taken equal
to 1.5 B.t.u.

The 20-ton machine working with am-
monia at 0 degree Fahrenheit can do
the 9.95 tons of refrigeration in 12 hours
if connected up to

: 4663 feet

1.6 X (32 — 0) X

of 2-inch pipe. If a machine having a
capacity of 15 tons refrigeration with am-
monia at 0 degree Fahrenheit, is operated
with ammonia at 12 degrees Fahrenheit,
its output, as already explained, is in-
creased to

15 X — = 19.28 Ions
4.2

It cen then do the summer work in

9.q.s X 24 ,

— =12.4 hours

19. .'8

but it must be connected with sufficient
piping to be able to do its work with 20

T \Ul.i; .'{ TdTAI. HEKKIGEU.VTION UKyilHKK IN 10-T<iN l'I..\NT

.Season

Coolinc
Coorls

Heat I>os?

Air
Renewal

.Men and
I^mps

Total
B.l.u.

Summer f

1,206.000
4 . n tons

1.461.0(16

+ .'..4.'.-9

7.1. .166
O.l Ions

34..-560

2.86.1.022

Autumn

1 ,008.000
■) r, Ions

070.416
+ 3.71-7.

.12.744
21 tons

34.360

2.074, .120

Winter

720.000
2 . ."> tons

16.0.16
+ 0 1.1-2

11.104
6.1 Ions

17.180

764.340

SprinfT

720.000
2 .5 Ions

6.18. 2fl6
+ 2.4H-4

.■iS.S64
98 Inns

17,1.80

1,434.340

In summer one ton of refrigeration takes
care of 60,30 cubic feet of storage space.
If this is to be a eas-cngine-driven
plant l( will be of advantage to be able
to shut down and to save the services
of an extra man at night. Nor is it neces-
sary to install a 20-ton machine. The
work can be done with a 15-ton machine

degrees temperature difference. It will,
therefore, require

2.86.S.022 ,. , , ^

, ^, , z—r: ^7212 Itnrnl jrrf

t.6 X {\2 — 12) X 12 4 ' '

The 15-ton machine could undoubtedly
he used to the best advantage, but to
prove this contention the comparison in
Table 4 is made.

As the engines are not being operated
at full rated load, an average consump-
tion of Zsi cubic feet of illuminating gas
may be assumed, which at SI per
thousand equals 2.5 cents per brake horse-
power-hour, or the same cost as with
gasolene at IS cents per gallon. These
figures are conservative. Lubricating oil

TABLE 4. COST OF EQUIPMENT FOR 10-
TON REFRIGERATING PLANT USING
MACHINES OF DIFFERENT SIZES

Capacit.v of com-

pressor, gas at 0°

10 tons

15 tons

20 tons

Operating tempera-

ture, gas at

0°F.

12° F.

0°F.

B.h.p. with 185 .!>

condenser p r e s -

sure, mcludmg 25

per cent, increase

over the compres-

sor horsepower . . .

21,3

32.4

42.5

B.h.p. gas engine

45

Cost installed, with

countersliaft and

belting, dollars . . .

1100

1.100

1850

Compresor p i s t 0 r

displacement i n

cubic feet per min-

54

108

Cojt of horizontal

belt-driven am-

monia compressor

with high-pressure

side, erected, dol-

2300

3500

Two-inch wrought-

iron expansion pip-

ing required, lineal

feet

2332

7212

4663

Cost of piping, in-

cluding liquid and

suction connec-

tions, cents per

Total cost of pip-

ing, dollars

1329

3.890

2565

Prime charge of an-

hydrous ammonia,

lb

750

Cost at 26 cents per

pound, dollars. . . .

195

520

364

Total first cost of

each plant. doUans

4924

8810 ■

8279

for the plant at 30 cents per gallon and
using 0.002 gallon per brake horsepower-
hour would cost 0.06 cent. All heat ab-
stracted is transferred ta the condenser
water, 200 B.t.u. for each ton, plus about
50 as the heat equivalent of the power
exerted in the compressor, the total being
250 B.t.u. per minute. If the condenser
water rises .30 degrees in temperature,
there will be required

250
30

= &% pounds

or 1 gallon per minute per ton. This
will also be ample for cooling the engines
afterward. An average rate would be 5
cents per 1000 gallons. The attendant's
time may be charged for at the rale of
30 cents per hour for the calculated run-
ning time. Me might do other work when
the machine is stopped. The fixed
charges in each case include interest on
first cost, 6 per cent.; depreciation, 5 per
cent.; repairs, 2 per cent.; taxes and in-
surance, 2 per cent.; total. 15 per cent.
The length of each season is 01 days.

In Table 5 the periods of running given
are the least needed by the machines to
do their work. Each machine operates
always at the same suction pressure and
upon all of the piping.

458

POWER

September 19, 1911

The conclusions to be drawn are, that
even with so small a maximum output
as 10 tons actual refrigeration per day,
rr^arked economy in operating 12 as
against 24 hours daily is doubtful when
the total yearly cost of operation is con-
sidered. In a plant of this capacity 12-
hour operation can be made to pay if the
power cost per ton of work is kept low.
Plants of 15 tons and more output per
day will have to be run continuously,
while below 10 tons the item of labor
per ton decreases with the running time.

Remembering that refrigeration, like
the pumping of water, requires less
power per ton when performed from high
than from low levels of temperature, one
is inclined to extend the short running

not sufficient in a small plant to offset the
increased labor cost attached to a longer
operating period.

With the 15-ton machine, for example,
the average daily running time in winter
could be extended from 3.3 hours to

764 .^40 U'lu.)

72iT(//.)X 1.5 («./.». )X i6{deg.diff.)Xi(lir.)
= 4.42 hours

the machine operating then at the rate of
14.39 tons refrigeration per 24 hours with
32 — 16 = 16-degree gas. At this .tem-
perature the displacement of the com-
pressor required per ton equals
3.76 (cubic feet) x" 14.39 = 54.1 cubic
feet per minute;

T.\BLE 5. C0.MPARAT1VE DAT.1 ON THREE .MACHINES AND COST riCl'RES

Season

Summer

.Autumn

Winter

Spring

Total for
Year

Tons refrigeration required per .sea,son

10-TON .Machine
Hours running, dailv

.?905.-l,5

24
2.184

12.4
1,128

12
1,092

S6.56.U

17.3
l,.'i74

9
819

s.e.i

787

S241.1.->

6.30
.">79

3.3
300

3.1s
290

.S453 . 18

11.95
1,088

.564

.5.98
.544

$2,255.89

Hours running per season

Per cent, of possible running time (364 days
X 24 = 8,736 hours) '

.5,425

B.h.p.-hours. 5,42.5X21 3- . .

Water, thousand gal. (same for all machines)

1.1-TON Machine
Hours running, daily

3.255

Per cent, of possible running time

32.2

20-TON Machine
Hours running, dailv

Hours running per season

2,713

B.h.p.-hours

Costs per Year

Size of machine used.

(ias bill

Lubricating oil

Water bill

.\raraonia loss, 10%, 1
^^■ages

Total net operating expenses.

Fixed charges

Total yearl.v cost

Total net operating expenses per ton refrigeration

Total yearly cost per ton refrigeration

Total yearly cost per cubic foot storage space* .
Total yearly cost saved over 10-ton machine . . .
ears required to recover excess first cost over 10-ton machine

10 tons

S2,8S8.83

69.33

162.75

19.50

1,627.. 50

.$4,767 . 91
738 . 60

$2.12
S2.44
9.1SC.

54.65
162.75

31.20
843.30

.$3,368.80
1,321.50

$1.50

»2.08

7.82c.

.$816.21

20 tons
$2,882.53
69.18
162.75
25.48
813.60

$3,953.54
1,241.85

$1.75
J2.30
S . 66c.
311.12
10.8

*These costs are about one-third of the rental charged per cubic foot 1

time, especially in winter, and to work
the machine with a higher suction pres-
sure; that is, with warmer ammonia. As
stated previously, the power per ton of
work done would then be lessened. The
limit in this direction is set by the tem-
perature difference which inust be inain-
tained if the proper relative humidity of
the cold air is not to be exceeded. With
20 to 22 degrees difference in tempera-
ture between the ammonia in pipes and
air in the rooms, the relative humidity
can be kept down to about 80 per cent,
without a fan; and with 16 degrees dif-
ference, to 85 per cent., unless some
source of moisture interferes. As will
be shown directly, the saving in power
realized with this scheme is unfortunately

while at normal speed this 15-ton com-
pressor displaces

15 >. 5.4 = 81 cubic feet

Its speed would, therefore, have to be re-
duced to 0.668 of normal. The brake
horsepower required would be
1.49 V 14.39 = 21.5

corresponding to only 61.4 per cent, of
35, the rated brake horsepower of the gas
engine. The brake horsepower-hours for
the season would be

402 X 21.5 = 8648

and if under this reduced load 27 cubic
feet of gas per brake horsepower-hour
assumed, the gas bill becomes $233.50
as against 9720 brake horsepower-hours

at 12 degrees Fahrenheit, which, at 2.5
cents, amount to S243. It therefore
means a saving of .S9.50 worth of gas,
also 64 cents worth of oil, but it would
be necessary to pay .S30.60 more for
labor. Nevertheless, machines are usu-
ally run longer, or are run a short time
mornings and afternoons, to prevent the
temperature in the rooms from fluctuat-
ing too much, as this is still cheaper than
to accumulate refrigeration in brine-stor-
age tanks, or by other means for the
purpose of continuing work after the ma-
chine has been stopped.

LETTER

Increasing Capacity of Com-

pression Plant

Three years ago I took charge of a
compression-system ice-making plant
having a capacity of 60 tons per 24
hours. There are two machines, one
having a capacity of 25 and the other a
capacity of 35 tons. For a number of
years previous to my taking charge the
plant had been a failure, the average
daily ice production being 40 tons.

As summer was near when I began
work, I had no time to make a thorough
investigation and had to do the best I
could until the season was over. During
the season's run my attention was drawn
to the forecooler, where a cooling coil
had been installed to cool the distilled
water previous to its going to the ice
cans. Over the cooling coils a wooden
box had been constructed, which com-
pletely hid the coils from view.

When the season was over I tore out
the box and found two 6-inch headers
corresponding in size to the 6-inch suc-
tion pipe leading from the brine tanks
to the machines. To the headers were
connected three 2-inch pipes. The 2-
inch pipes told me the story of the
failure at a glance. I removed the coils
and drilled and tapped the headers for
seven more 2-inch pipes. This made 10
pipes altogether. As it take« nine 2-
inch pipes to equal the area of one 6-
inch, it may be readily seen how much
the returning gas was restricted in its
flow from the tanks to the machines.

When we started up the next season

in full, we turned out from 66 to 70 tons

of ice every 24 hours, and we have kept

up this record each season ever since.

.1. A. Blackstone.

Youngstown, O.

kn approximate rule for the length of
belting is as follows: .\dd the diameter
of the pulleys together, divide the sum
by 2, multiply the quotient by 3 '4 and
add the product to twice the distance be
tween the centers of the shafts. An even
better nile than this is to cut out the
figuring and use a tape line round the
pulleys.

i

September 19, 1911

POWER

The Professional Spirit

It would be a very obvious question
if someone were to ask, what is an op-
erating engineer? The most obvious and
direct reply to the question is, an op-
erating engineer is a man who operates
an engine. But if this organization (the
Institute of Operating Engineers) means
anything, if it thus far stands for any-
thing at all, it stands opposed to any such
definition. The operating engineer who
is a master of his craft must be very
much more than an engine operator. The
Institute of Operating Engineers is not
intended to be a society of machinery
attendants; it is a professional body of
national — yes, international — scope, in-
cluding all men who have to do with the
responsible care of machinery in motion.
Our national institutes of mining and
electrical engineers have their perfectly
definite fields: the civil engineers deal
with structures; the mechanical engi-
neers design machinery; we operating
engineers make it go and keep it going.

We should take an unnecessarily mod-
est view of our function if we concluded,
therefore, that the operating engineer is
a caretaker, a hand worker, while all the
other engineers are brain workers. We
are a necessary part in that mechanism
of production of which they also are
parts. The great raw material with which
we work is fuel, brought to us by the
mining engineer. The electrical and me-
chanical engineers provide us with tools
to work with, in edifices and structures
which we owe to the genius of the civil
engineer or the architect. From fuel we
produce power and light and heat and
those other services which have become
essential to civilized humanity. Their
production with efficiency and effective-
ness depends in a peculiar way upon us.
The operating engineer is the most im-
portant single factor in the performance
of the power plant.

Our Institute, then, recognizing the
commercial importance of the work of
its members — the momentous issues
which depend upon them — seeks to ob-
tain for them commensurate recognition.
It would substitute logarithms for over-
alls, the slide rule for a monkey wrench,
perhaps a rolltop desk for a tin dinner
pall. But these are only parts of Its
aim. As long as the operating engineer
Is denied the recognition his work merits,
just so long will the field of operating en-
gineering fail in a general degree to at-
tract the best type of men.

Our young men become foremen, de-
signers, construction men — but they rare-
ly go in for power-plant operation. Why?
Because, while the responsibility and the
opportunity for efficiency there arc as
great as anywhere else, the conditions of
work are oppressive and the reward for
efDciency inadequate. Under present cir-

By W. D. Ennis

TIic opcratnii:, oigiuecy is
a business manager. He
has leonderful opportuni-
ties. Whether he profits
by them depends completely
on himself. The Institute
of Operating Engineers
slwnld cultivate the faculty
of self -education.

*.\listract iif aiidrcss ilelivervil at aiiiinal
nii'ptina "f the Institute of Uperatins; F.nt:iii-
.prs. N.w York. Sept. 1. i:ni.

cumstances the man who enters operat-
ing engineering must make some distinct
sacrifices. Two results follow: The pro-
fession secures a few, and only a few,
devoted men of the highest type; men
who must, because of their very make-up,
be engineers, men who are impelled to
that work just as St. Paul was impelled
to preach the gospel, who would be en-
gineers for fun, even if they had to be
something else for a living. It also se-
cures a large proportion of men not of
the second but of the third and fourth
ranks, men who go in for plant operation
because of lack of ambition to enter
more promising fields.

The bad conditions in operating engi-
neering thus react, bringing into ihe
vocation men not qualified to measure
up to their opportunities; men too small
in intellectual stature to handle the prob-
lems involved in making power from
coal. This is the more serious problem
that our organization aims u4timately to
rectify. The operating engineer is to be
a professional man in precisely the same
sense as the civil engineer may be.

The steam engine, as a working ma-
chine on a broad commercial scale, is
little more than a century old. A hun-
dred years ago, when it first became
generally known, it was the fashion in
certain quarters to decry machinery and
its effects. Such honest men and great
thinkers as Thomas Carlyle and John
Ruskin, for example, feared that the
beauty of life would disappear and the
dignity and art of handicraft be eliminated
by the advent of such things as the power
loom, the spinning jenny and the engine.
They denounced the coming age as one
of mechanism rather than of men, one in
which landscapes would be blotted out
by coal smoke and waterfalls drained
that mills might run.

Yet on the whole, while chimney and
furnace smoke inay disfigure the land and
in places mar its beauty, nevertheless
steam power has, perhaps more than any

other material invention, raised rather
than lowered human nature and human-
ity's capacity and opportunity for enjoy-
ment.

Power does not enslave men; it sets
men free. It substitutes brainwork for
handwork, skill for brute strength. The
workman of today has but to guide the
tool. The invisible engine far off pro-
vides the effort. All of the unconsidered
conveniences of civilization we owe in a
large measure to artificial power.

In its practical everyday aspects, let us
regard the scope of activity of the en-
gineer. We have already considered his
interest in the provision of light, heat
and ventilation. He has charge also of
the elevators and other machinery of a
modern building; in hotels and hospitals
he supplies steam and refrigeration for
a score of purposes; he supervises the
generation of electric, hydraulic, pneu-
matic and other forms of power; he is
responsible for the intricate equipment
involved in modern fire-prevention sys-
tems. In manufacturing plants, he may
have the care not only of the apparatus
connected with the utilization of steam
in process work, but also of the machin-
ery and physical plant as a whole. Sev-
eral of this Institute's members are at
the head of important works; for it is
by no means an illogical step for the
man who progresses from the generation
of power to its utilization — and thence to
the care of apparatus and structures and
the supervision of nonproductive material
stores, with responsibility perhaps for the
largest items in production cost — to con-
trol ultimately the general and imma-
terial mechanism of that production.

In New York City and other large
municipalities every operating engineer
in responsible charge of a private power
plant is a competitor of the public light-
ing and power corporation. He is no
greasy mechanic; he is a man engaged in
a strenuous business, bound to show in
his final costs the reason for his existence
and against him are massed the best en-
gineering and commercial talents of a
highly developed organization. The man
who can live against such odds is no
small man.

The object of the Institute of Operating
Engineers, in one word, is service — higher
service. That object includes, or will
include, all others. The man who serves
most deserves most; in the long run,
attains most. We wish to be professional
men rather than machinery operators.
Both the justice and the realization of our
ambition will be for a time denied us.
If we seek to attain it by demagogic agi-
tation or undue self-assertion, they may
be effectively denied us for a long time
to come. But if our platform be this,
we know that the wastes of the power

460

POWER

September 19, 1911

plant are largely due to bad operation;
we purpose to better that operation by
inducing better trained and better edu-
cated men to enter power-plant service,
then that ideal of higher service must
appeal to all and offend none.

The improvement in education and
training which this Institute proposes as
a remedy for present bad conditions will
be brought about in various ways. First
of all, we must make the fullest pos-
sible use of all existing agencies. The
technical press, or at least that part of it
which deals particularly with power-plant
matters, is one of the foremost of the
educational influences with which we
must as a matter of course cooperate.
Schools and colleges, in their regular or
extension courses, and correspondence
schools as well — all of these have their
special fields of efficient work. They and
we will be mutually helpful as we bring
their activities close to our membership.
Here in the city of New York oppor-
tunities for higher study have already
been provided. At Columbia University
classes have been conducted for some
years in certain instances, under the in-
struction of men who are members of
this Institute, in various subjects pertinent
to operating engineering. In the borough
of Brooklyn another educational institu-
tion will, it is expected, offer this winter
courses of study contemplated in the
requirements laid down for the grade of
master operating engineer.

But, in order to develop the genuine
type of professional spirit among our
members, present and future, we need
something more than trade schooling or
even technical education. Two or three
initial letters after a man's name do not
make him an engineer. No school or
university can make an engineer. It takes
time and some dirt and perspiration and
a good boss — and a variety of other
things to do that. There can be no true
professional spirit among us until we de-
velop the faculty for self-education. We
are apt mistakenly to think that our
brother engineers in the civil and mechan-
ical branches get their "theory" in school
and their practice afterward. On the con-
trary, the most important engineers I
know are devoting a great deal more of
effort to theoretical study — namely, to a
mastery of first principles — now, than
they ever did as students. So also must
we. An engineering society becomes of
great national importance only as it be-
comes a clearing house for original
scientific thought.

To summarize, what are the essentials
of the so called professional spirit?
Perhaps we may say, activities which in-
volve brain work rather than hand work;
a clearly defined special field, in our
case the responsible care of machinery
in motion; commercial and industrial and
social importance of the vocation; and
finally a strict responsibility for ultimate
costs and ultimate results.

The operating engineer is a business
manager. We do not ordinarily regard
a business manager as a professional
man. Indeed, there has always been a
strong distinction drawn between com-
mercial (or industrial) and professional
occupations. For the past three years
we have been reading a great deal about
managers and management — scientific
management and other kinds of manage-
ment. The papers have been full of it
and our heads have been bewildered by
it. What does it all mean? Simply this,
that management is becoming a profes-
sion, like law or medicine or (most no-
tably of all) engineering. Men are no
longer to be managers by divine right;
they are to learn to rule, and to rule con-
stitutionally, just as all kings on the
other side of the water have had to learn
in the last century or two.

This movement was due, as I view it,
to the mechanical engineer, the trained,
educated mechanical engineer. Going into
the shops and mills, he revolutionized
methods and processes by applying his
superior knowledge of fundamental prin-
ciples, and now he is revolutionizing man-
agement. The manager of today is more
and more frequently a trained engineer
(once he was a graduated office boy),
and management is now recognized as
based on certain fundamental principles,
just as engineering is. We do not know
them all yet, but we are steadily dis-
covering them.

The best training for producing a man-
ager has not yet been ascertained. One
good kind of preparation is the study of
engineering. As has been said, engineer-
ing is superlatively a professional voca-
tion. To be an engineer alone goes far
toward fitting a man for a position of ex-
ecutive authority, and this is most par-
ticularly true in operating engineering.
In the factory as a whole the mechanical
engineer has many rivals for the chief
position. The head bookkeeper, or even
the head stenographer, may "win out"
over him. But in the power department,
what rival has the operating engineer?
If he fails to manage his work in a
businesslike and efficient way, there is
not a soul on earth to do it for him.

.And just there lies our strength and our
weakness. The opportunity is wholly
ours; it is the greatest opportunity ever
turned over to a single set of men; but
because no one competes with us for it
we often, in the great majority of cases,
I fear, fail to grasp it adequately. I
repeat, then, the operating engineer's
work is that of a business manager. He
is given a plant, required to maintain it
in good condition and held responsible
for the cost of power. In theory if not
always in fact, he has a clean-cut busi-
ness proposition, and if the final result
is what it should be, then, humanly
speaking, there is nothing on earth too
good for him.

The Chief and the Governor

By H. M. Phillips

Strange performances that add to the
joy of living take place in the world of
mechanics frequently and at all places,
but the record of the old A. and B. plant
will probably never be surpassed.

The plant had been idle for a year or
more and there was the usual trouble
in getting an extensive though by no
means modern steam plant into operating
condition; in the midst of w-hich the
chief engineer departed, never to return.
There were several men on the job who
applied for the vacant position; it is hard
to say why the "hero" of this story was
chosen, unless it was because he had
never had anything to do with the steam
plant before so that there w'as nothing
in that particular line against him.

At the time of his appointment there
was but one engine running, a small
Porter, with a "Gardner" governor, that
drove a generator supplying light and
power for a few motors. Several days
passed without disaster and the chief
grew in importance ; then the governor
belt broke. The safety stop did its work,
the chief was soon on the spot and he
lost no time in getting on a new belt;
but the engine would not run (the safety
catch had not been reset). After a
somewhat lengthy investigation the
trouble was traced to the governor and
the chief took it apart, and by the time
he was through with it there was real
trouble and it had to be sent to the ma-
chine shop for repairs that would take
the better part of 24 hours. Lights and
motors were indispensable, however, and
the engine was therefore run without a
governor. An assistant engineer was sta-
tioned at the throttle and a dynamo tender
at the rheostat, and, although the ser-
vice was not of the best they both earned
their pay that day.

The chief was not exempt from the
rule requiring a time card to be filled
out each day. The card was of unusual
size, with ample space allowed for the
different jobs upon which a man worked.
If you had never before realized the im-
portance of the position of chief engineer
you could hardly fail to do so — at least,
you could be certain that the chief him-
self did so — by a glance at his time
card. Written diagonally across its face,
in a remarkably bold and aggressive
hand that filled the entire space, was:
Acting Chief Engineer

On the day following the trouble the
chief's card came to the office as usual;
and another card lay close to it in the
pile; it was that of the hard-worked man
at the throttle. The general style of
the latter's card closely followed that of
the chief's; there was the same bold and
aggressive handwriting, if anything, a
trifle larger and heavier, but the wording
was slightly different. It read:
Acting Governor

September 19, 1911

POWER

Jahns Engine and I'urbine
Governor

In the accompanying illustrations the
Jahns steam-engine and turbine governor
is shown in detail. A skeleton of the

Fig. 1. Governor Base

governor is shown in Fig. 1 ; the two
main weights are shown in position in
Fig. 2, and a sectional view of the gov-
ernor is shown in Fig. 3.

The two weights are guided in a radial
straight line perpendicular to the spindle
by three rolls on the lower surface sus-
taining the weights and two rolls on the

Fig. 2. Governor Weights

sides resisting the force of inertia which
would fend to keep the weights revolv-
ing at the same rale while the engine -
and, therefore, the governor casing in-
creases or decreases its speed by an
inRnitesimal amount. The centrifugal

force of each weight acts directly upon
its spring so that all lever joints are
entirely free from any centrifugal or
spring force.

The transmission of the motion of the
weights to the sliding sleeve on the
spindle is effected by the bell cranks
fulcrumed on the lower casing, the upper

mitted to the sleeve, is practically a con-
stant force, being the same for each
position of the sleeve throughout its
stroke.

The casing is entirely inclosed, as
shown in Fig. 4. and all of the lower
pins and slides are in a bath of oil. The
oiling of the upper pins and slides is
effected through the oil cup on the top
of the governor and can be done while
the governor is in motion. When the oil
has attained a certain hight any addi-
tional amount will cause an overflow.
This surplus is conducted to the rub-
bing surfaces of the sliding spool located
below and outside of the casing. In this
manner every point of possible friction
is automatically oiled.

The governor possesses small internal

Fic. 3. Section through Governor

arms engaging, by means of rolls, the
vertical straight slots in the weights; the
lower arms engage in sloping slots in the
spindle sleeve. The angle of this slope
is fixed in such a manner that the cen-
trifugal force of the weights, as trans-

friction, the lever joints being free from
all centrifugal and spring forces, and
from any side strain caused by force of
inertia of the weights. There is also the
least possibility of change in the working
parts through wear.

462

POWER

September 19. 1911

In case an adjustment of the governor
not exceeding 10 per cent, is desired, a
speed regulator may be used.

A change in the revolution of the gov-
ernor is accomplished by means of a
spring so arranged that it can be loaded
or unloaded, and giving a constant down-
ward pull on the sliding sleeve at all
times.

Fig. 4. Governor Complete

In Fig. 5 is shown a variable-speed
governor, which by means of an auxiliary
spring located inside of the regular
stand, it is claimed, is capable of taking
care of a variation of 100 per cent.

The auxiliary spring surrounds the
governor spindle and rotates with it, the
lower end of the spring resting on a
collar which is free on the spindle but
is supported by a cross key passing
through a rod inside the governor spin-
dle, which is hollow. This rod trans-
mits the pressure of the auxiliary spring,
by means of a key, to the roll sleeve
which is located inside the governor.

The upper end of the auxiliary spring
has a collar resting upon it which is
also loose on the spindle and turns with
it. The upper side of this collar forms
half of a ball bearing, the other half
of which is part of a collar surrounding
the spindle, and has ears which pass
out through slots in the side of the gov-
ernor stand, the ears keeping this col-
lar from revolving; the outer ends of the
collar ears are attached to a handwheel
which fits the threaded portion of the
outside of the pedestal; therefore, ad-
justing this handwheel will compress or
release the spring to any desired amount.

This type of governor is particularly
adaptable to compressors and pumps.

These governors are manufactured by
the Massey Alachine Company, Water-
town, N. Y.

Consolidated Safety Valve

In designing this valve the spring has
been so proportioned that it will have
the best values for both fiber stress and
compression under the highest steam
pressures.

The spindle of this valve has a central
thrust upon the valve disk and the spring
is prevented from binding on the spindle
by mounting the spring to the end of
the compression screw above and to the
spindle below. This consists of two ball-
and-socket bearings of the same size
which allow the spring ends to freely
assume their normal position.

The upper trunk of the valve disk
overlaps the outside of the spring case.
This practically leaves no area upon the
top of the disk exposed to the exhaust-
steam pressure and makes the valve disk
entirely independent of pressure condi-
tions within the valve case.

Fig. 5. Variable-speed Governor

Another feature is the hand-ground
balled seats which maintain a bearing at
the seat despite any axial change of the
disk position.

The long, broad-faced wings of the
feather below the seat and the ample
bearing of its trunk on the spring case
above, together with the low bearing of
the spindle upon the feather, make the

lifting of the valve smooth and positive
in action.

The blow-back adjustment of this valve
is obtained by means of the original
Richardson adjusting ring. It not only
gives a definite and positive control of
the blow-back adjustment for close or
wide regulation, but forms a factor in
obtaining the large relieving capacities
of these valves. A relief nut on the top
of the stationary valve spindle makes It
possible to take the valve apart for re-

CONSOLIDATED SAFETY VALVE, "TyPE B"

grinding or inspection w'ithout disturbing
the adjustment of the valve.

In this type of valve the casing is
made of steel, but the brushing and
other mountings are of nickel. The valve
is designed for ser\'ice where superheated
steam is used. The spring is exposed to
the atmosphere and steam does not come
in contact with it. By referring to the
illustration it will be seen that the valve
body is cast with a steam passage around
the outside of the valve seat. The upper
section of the valve is made with a
projection upon which the valve disk is
guided as it opens and closes. This also
prevents the steam from escaping around
the spring.

VChen the valve blows the valve disk
is lifted, thus compressing the spring.
Steam escapes through the opening be-
tween the valve disk and seat into the
chamber surrounding them and escapes
to the atmosphere through the opening at
the left. This valve is manufactured by
the Consolidated Safety Valve Company,
8,=^ to 87 Liberty street. New York City.

In Paris recently a monument was un-
veiled on the Place Saint Ferdinand des
Ternes to Leon Serpollet, whose initial
journey from Paris to Lyons in his steam
car in 1890 caused a sensation. When
he first drove about the streets of Paris,
numerous complaints were made to the
prefect of police that the lives of citi-
zens were being endangered while cross-
ing the streets.

September 19, 1911

POWER

463

Minnesota State Convention,
N. A. S. E.

The second and by far the most suc-
cessful convention of the Minnesota State
Association of the National Association
of Stationary Engineers was held at St.
Paul, Minn., August 23 to 26. President
H. M. Germain presided throughout the
four days' sessions. The convention was
called to order by Past President J. M.
Williams, of Minneapolis, and addresses
of welcome were delivered by Mayor
Herbert P. Keller, of St. Paul, a member
of the organization, and by Mayor James

C. Haynes, of Minneapolis.

During the different sessions a number
of interesting and instructive lectures
were delivered. Henry Sims, of Erie,
Perm., president of the Sims Company.
spoke Wednesday on "Feed-water Heat-
ers," and ex-National President Wilson
gave a very able discussion on boilers at
Saturday's meeting.

Among the others who spoke were H.

D. Barnard, of Minneapolis, on "Incan-
descent Lights"; National Secretary Fred
Raven, on "The License Law"; Gen.
Henry Harris, of Chicago, on "The Op-
portuniHes of a Stationary Engineer";
W. A. Converse, of Chicago, on "Boiler
Troubles Attributable to Feed-water Heat-
ers"; E. P. Carish, of Minneapolis, as-
sisted by E. Powers, of St. Paul, on
"Ventilation."

The committee reported 32 delegates
present at the convention, and the general
attendance was in the vicinity of 3()0. The
association, following the recommenda-
tions of the legislative committee, decided
to set aside a sum of money not to ex-
ceed S500 a year for legislative purposes,
providing this was possible. It was de-
cided also to appropriate S200 yearly for
assisting the officers in forming new or-
ganizations.

The convention unanimously indorsed
Fred W. Raven for reelection as national
secretary and adopted resolutions indors-
ing Jesse M. Williams, of Minneapolis,
for vice-president of the national associa-
tion.

The president's message was read on
Thursday evening. In it he spoke of the
progress which the association had made
during the last year and said the poor
showing that had been made in organiz-
ing new associations was due to lack of
funds and not to any lack of energy by
the officers.

During the past year the State law has
been kept prominently before the people.
Several open discussions on this subject
were held during the convention and the
members were roundly scored at different
times for their lack of energy in this
matter. It was shown that the cor^-
mittee having the work in hand had
labored continuously to secure the pass-
age of the bill by the Minnesota legis-
lature, but that their efforts had failed
Just when everything seemed accom-

plished. In his discussion on this sub-
ject, Mr. Raven said that the association
could hardly expect to do everything in
one year; and that it must educate the
engineers themselves and the public as to
just what good will be accomplished by
the bill. Mr. Raven also asked that the
delegates to the national convention be
instructed to support the appropriation of
a budget for the purpose of helping new
associations.

Over 45 manufacturers and retail deal-
ers exhibited their products at the con-
vention. This was made a special feature
of the work and the results were highly
satisfactory.

During the week a number of social
affairs were arranged. The election of
officers was held Saturday and resulted
as follows: F. J. Streiff. president; J. P.
Crane, vice-president; James McGeary,
secretary; Albert Johnson, treasurer; T.
S. F. Hayes, State deputy; P. B. Wells,
conductor; W. Mclver, doorkeeper; J.
Orbeck, trustee for three years; J. D.
Roberts, trustee for two years.

OBITUARY

George K. Lloyd, for 25 years engi-
neer at the Queen Dyeing Company's
plant at Providence, R. I., died at his
home in that city on September 1. He
was one of the best known engineers in
the New England textile field. Mr. Lloyd
was born in Baltimore, but came to Provi-
dence when a young man. He is survived
by two daughters and a son, who is an
engineer at the Queen plant. The funeral
was held on Monday. September 4, from
his late residence.

PERSONAL

C. E. Alillcr will be in charge nf the
branch office opened on September 1 1 by
the Standard Welding Company, of
Cleveland, O., in the Ford building. De-
troit, Mich.

W. W. Reece, formerly of the Corn
Products Refining Company, has recent-
ly taken charge of the power-plant econ-
omy department of the W. H. Zimmerman
Company, engineers and constructors,
offices in the First National B.ink build-
ing, Chicago, III.

Thomas H. Plati, who is well known to
the engineers of New York, is now as-
sociated with the Dearborn Drug and
Chemical Works, and will make his head-
quarters at the Eastern office of the com-
pany. 29M Broadway, New York. Mr.
Piatt's territory will comprise Greater
New York.

pany, of Pittsburg, Penn., to handle its
line of valves, fittings, flanges, pipe bends,
fabricated pipe and other power-plant
material in the same territory. He will
make his headquarters in Kansas City.

Louis Bendit has been appointed by
the Hope Engineering and Supply Com-
pany, of Pittsburg, as manager of its
Western office at the New York Life
building, Kansas City, Mo. Mr. Bendit
will have associated with him a corps of
experienced engineers and will be pre-
pared to give careful attention to all in-
quiries in consulting and contracting en-
gineering along the line of natural gas.
He will also have charge of its sales
agencies cf Miller gas and oil engines,
C. & G. Cooper gas engines, Hammon
gas-pipe couplers and Sprague gas
meters.

Benjamin T. Delafield, who formerly
represented Lunkcnheimer Company for
a number of years in the St. Louis and
Kanxas City territory, has become con-
nected with the Best Manufacturing Com-

Chicaco's Smoke Inspectoi?

SOCIETY NOTES

At a recent meeting of the executive
committee of the American Society of
Mechanical Engineers, the following com-
mittee on standard rules for care and
construction of boilers was appointed,
subject to the approval of the council:
Jehn A. Stevens, Lowell, Mass., chair-
man; Edward F. Miller, Boston, Mass.
Charles L. Huston, Coatesville, Penn.
Herman C. Meinholtz, St. Louis, Mo.
R. C. Carpenter. Ithaca, N. Y.; William
H. Boehm, New York, and Richard Ham-
mond, Buffalo, N. Y. From the experi-
ence of the society in regard to its codes
for testing boilers, engines, etc., there is
reason to believe that a set of carefully
prepared specifications, formulated and
recommended by such a committee will
he recognized as a standard by legis-
latures and officials, and that uniformity
in legal provisions will thus be obtained.

464

POWER

September 19, 1911

Graham Hood, who writes
the Htlle stories of practical,
every-day philosophy for the
New York Evening Globe,
recently published one on
the importance of a man's
equip])ing himself with the
right knowledge and train-
ing, in the right way, and
at the right time in his career.

To quote a part of it:

" If there is anything that it is absolutely
necessary that you should know, especially
in your business life, there is every probability
that you will in some way manage to acquire
this information some time. If you are
wise you will go about the work of acquiring
this knowledge systematically, beginning at
the earliest possible moment. Because you
fail to do this, however, don't imagine for a
moment that you are to go through life in the
state of ignorance that you have adopted.
Even though you might be so foolish as to
deliberately elect to know nothing that might
help you get on in the world, you can't
keep yourself from gaining this knowledge,
for the only way to escape the lessons that
Schoolmaster Experience teaches is to stop
living. As long as breath remains in our
bodies we are compelled to continue our
studies in this school.

"The mistake that a great many persons
make, however, is that of waiting until the
knowledge comes to them instead of going
after it. It may be true that the knowledge
may come eventually, but
what are to become of the
countless opportunities when
the sometime-to-be-acquired
knowledge would enable you
to change a failure into a
successful achievement ?

"It is true that it costs some-
thing to secure this know-
ledge at first hand. It costs
a great deal of time, much
patience and persistence, and

possibly a little money, but
if you could compare the
cost of the knowledge you
get in this way, and that for
which you have to wait un-
til experience can get a
chance to teach you, you
would be amazed to see how
much cheaper it is to se-
cure your training in the right way.

"In the first place, the man who knows just
what he wants to do, arid exactly how he
should go to work to get these results, reduces
the possibility of mistakes and ^failure to a
minimum. Mishaps may occur, for it is not
easy to devise a positive safeguard against
such incidents, but should they happen the
man who knows how can usuallv find an easy
way to remedy them. It is the fellow who
does not know, and who is waiting for experi-
ence to teach him, who falls into all sorts of
costly pitfalls. Experience does teach him
in time, but in the meanwhile he must meet
the cost of his experiments, and the expense
of tuition in the School of Experience is far
in excess of that which is charged for the
thorough training that he may so easily
secure at the beginning of his career."

The moral is, don't wait until knowledge
comes to you — go after it.

It is Power's business to bring you a
fund of valuable knowledge every week — all
you need to do is to go after it, to read it.

The advertising section of this paper rep-
resents in reality an enor-
mous, costly system of en-
gineering education, which
comes to you every week.

If you don't conscientiously
read and study the ads you
are neglecting a great oppor-
■ tunity.

The information is there —
go after it.

\-ol. S4

NEW YORK, SEFTEi\IBf:R 2b, 191

No.

IF it were not for that somethmg called hope, the
world would be filled with discouraged, listless
human beings who would merely exist.

Hope braces a man up. makes him battle against
odds, encourages him to undertake enterprises that
appear to be doomed to disaster before their comple-
tion.

It is hope that incites the laborer to work from
ten to twelve hours a day for Si. 50. He hopes the
boss wall recognize his worth and increase his wages
to S2, and although his hopes are rarely realized he
keeps plodding on.

It was hope that prompted a correspondent to write:
■• If we make good in the plant the company will
make good in the pay envelop." If this engineer
is of the average caliber, he is getting between fifteen
and eighteen dollars a week. He has served his
company faithfully from the beginning of his ser-
vice; no work has been too arduous, no hours too long,
no Sunday so sacred and no time so precious that
he could not give all to his company. His hours do
not begin and end with the blowing of the whistle;
often he is the only one employed in the steam plant,
and does his own firing besides running the engine

He has been spurred on by
the hope that his faithful service
would be recognized in time.
His ambition to succeed has been
such that hours have been spent
in study and planning improve-
ments which will bring about
greater economy.

What is the result? Occa-
sirmally a ca.se is heard of where
the cherished hope of a volun-
tary increase in wage has been
realized, but in the majority of
instances the engineer's ability,
•ilthrrugh recognized, goes un-
1 1- warded

If the engineer is offered a more remunerative posi-
tion in another plant, the company, knowing of his
ability and his real worth to them, then usually offers
him an increase in wages equal to that accompanying
the new position. This means that the engineer had
not been getting what the company knew he was worth.
The engineer had not been getting what was due him
because he had waited in the hope that the company-
would volimtarily pay him what he was worth, and
not at the rate at which another engineer could be
hired.

Men have often refused inducements to sever their
connections because the company has used them
square, and entertaining such feelings are sure to give
the best of ser\-ice for value received.

A dissatisfied engineer is a detriment to the success
of any company. His heart is not in his work, and
he does no more than is necessary to hold his job, —
thereby costing his company a gofxi many dollars
by his indifference.

Apparently, the fact that an engineer appreciates
recognition of his worth is lost sight of and, so long
as the wheels turn, the company seems to be satisfied;
the cost of coal and supplies
is of little account, but the
engineer's wages loom up in an
alarmin::: manner.

Some day we hojic that the
plant owner will see the wisdom

-— of voluntarily increasing the pay
of his engineer It will not cost
him much — he will get most,

— if not all, of it back by a more
strict attention to affairs l)y
the engineer There is no better
way of increasing the efficiency
of a man than by stimulating
his efforts by an occasional in-
crea,se in his |)ay envelop.

POWER

September 26. 191!

The Steam

The Maffei-Schwartzkopff NJCorks, of
Berlin, build turbines of the Melms &
Pfenninger type. This type was originally
developed by a firm of like name in
Munich-Hierschau and is now manufac-
tured by these firms on the Continent:
the Maffei Locomotive Works, in Munich;
the Kolben Electric Manufacturing Com-
pany and the machine works of (former-
ly) Breitfeld, Denek & Co., in Prague;
and the Schichau Shipbuilding Company
in Elbing and Dantzic. Similar in prin-
ciple to the Brown, Boveri turbine, the
Melms & Pfenninger turbine is the out-
come of a successful attempt to combine
the advantages of the impulse type, in
the high-pressure element, with the recog-
nized high efficiency of the Parsons type
in the intermediate- and low-pressure ele-
ments.

To provide for good packing between
the various elements the pure-impulse
type of turbine must have a small shaft,
and to provide for the bending of this
shaft the clearances between it and the
walls of the diaphragm, forming the
partitions between successive wheels,
must be made amply large. These re-
quirements work at cross purposes. The
steam which leaks past the clearance
without doing useful work is unavoidable.
Moreover, wheels running in a space filled

Turbine in Germany

By F. E. Junge

The

coiisiruction and econ-

OD! r

of the- Mel

ms & Pfen-

III Hil,

ir tiiyhine,

leliicli is of

III,

iiiilnihe /

r/r hi the

llli^h

-pressure i

lenient and

oj 1

'arsons dc

ugn in the

iiiicnncdiatc ai

d loiv-pres-

sure

stages.

The pure-reaction type, on the other
hand, in order to have sufficient blade
hight of the first rows, must have a very
small drum diameter on the high-pres-
sure side, a certain length of the high-
pressure blades being necessary to main-

becomes abnormally long. The length of
the high-pressure section of a Parsons
turbine, contributing one-quarter of the
total useful work, is often three-quarters
of the length of the remainder of the
turbine, while the efficiency of the high-
pressure end is substantially lower than
that of the low-pressure end, the ratio
in the case of a marine turbine tested
being 55 to 63 per cent. This low effi-
ciency is due to the large amount of
high-pressure steam which leaks through
the clearances above the blade tips, in
spite of the low steam and blade velocities
employed. In the case of an impulse
turbine, on the other hand, the blade
speed is frequently the same at the high-
pressure as at the low-pressure end, a
condition rendered possible because it is
practicable to run impulse turbines with
partial admission.

In the partially impinged impulse sec-
tion of the Melms & Pfenninger turbine
a considerable portion of the available
pressure drop is utilized — before the
steam is conducted to the reaction part
for further expanding. Thus the first
reaction blades can be made much longer

Fig. 1. Oricinai. Design of .Mel.ms & Pfenninger Turbine, 3000 Horsepower

with high-pressure steam involve addi-
tional losses through disk friction. Final-
ly, the complicated structure of the pure-
impulse type and the expensive machin-
ing of its various parts make the total
cost of manufacture high.

tain a favorable ratio of the useful blade
area to the radial or clearance between
the fixed and moving parts. Hence, to
attain a given turning moment an in-
creased number of rows is required, and
the length of the high-pressure element

than the shortest blades of an equivalent
pure-impulse turbine, and the radial and
axial clearances are kept amply large
without endangering the steam economy
of the turbine. In the impulse part of
this turbine a fivefold expansion of steam

September 26. 191 1

POWER

467

takes place as against a hundredfold ex-
pansion in an equivalent number of
blades of a pure-impulse turbine. Hence
the drawbacks of the latter type are mini-
mized, especially so because the pack-
ing of the various elements is done by
means of slots which are regulable in
axial direction, and the respective clear-
ances can be easily adjusted to the com-
paratively small pressure drop of each
stage. That the efficiency of the impulse
section in the Melms & Pfenninger com-
bination is higher than that of a corre-
sponding section of pure-reaction tur-
bines is proved by the favorable results
of several tests made on turbines of from

the bypass valve £. A relief valve is fit-
ted at G which opens if the pressure in
the exhaust branch rises above that of
the atmosphere, and thus prevents a
possible rupture of the condenser. A
gland H is fitted between the exhaust
pipe and the top of the condenser, and
over this gland a water seal is constantly
maintained to prevent any possibility of
air leakage.

The turbine illustrated is rated to de-
velop 3000 horsepower when running at
1500 revolutions per minute. The drum
diameter in section A is 40.2 inches, and
its thickness l}s inches. At the inter-
mediate section B the drum diameter is
30.6 inches, while the low-pressure sec-
tion has a diameter of 42.9 inches, the
overall length of the drum being 60.8

section passes right round the inner edge
of the diaphragm and extends into a
groove cut in the drum. Leakage of
steam can only then take place through
the clearance marked, and this clearance
is adjustable by moving the rotor axia'ly
by means of the micrometer screws pro-
vided for this purpose at the turbine
thrust block. Hereby the leakage losses
of the drum arrangement are brought
down to a similar low figure as attends
the employment of disk wheels. The
makers state that owing to the short
length and large diameter of the drum it
has been found quite practicable to work
with a clearance of but 10 mils between

Figs. 2 and 3. Sectional Views of Turbine

100 to 5000 horsepower capacity referred
to later.

From the accompanying Figs. 1, 2 and
3, it may be seen that the steam enters
the turbine through the governor valve F,
the position of which is controlled by a
steam relay, whence it proceeds into the
impulse section of drum A. Its escape to
the left is checked by a labyrinth pack-
ing. At the end of the impulse section
the drum is reduced in diameter, and
the pressure of the steam on the shoulder
to the left ser\'es to balance the axial
thrust of the steam to the right, as it
flows on through the reaction blading in
drum sections B and C. In the case of
an overload steam is admitted directly
to the reaction part of the turbine through

inches, as compared with 8 feet, the
usual length of arm for a pure-reaction
turbine of corresponding output. Fig. 4
shows the form of packing used to
minimize leakage between the guide-blade
diaphragms and the moving drums. The
admission being partial, the guide blades
occupy only a portion of the total area
of this diaphragm, which consists for
the main part of a solid ring 0.04 inch
thick, and in the case of the turbine
shown in Figs. 1, 2 and 3 about I'i
inches deep in the radial direction. At
certain symmetrically arranged points the
ring is cut away and a foundation strip
carrying 10 or more nickel-steel guide
blades inserted; this foundation strip is
calked into place. A shrouding of L-

tlic nearest points of the opposed fixed
and moving surfaces.

The impulse blades. Fig. 5, are of the
usual symmetrical pattern, let into a
foundation ring. This ring is secured
to the drum by double calking strips, one
of a soft brass and the other of steel.
Fig. 4 shows diagrammatically the joint
ready for calking, and after this opera-
tion has been finished, when the steel
key piece is bent over as indicated. The
rim which connects the outer ends of the
impulse blades and whose cross-section
approaches the form of a sickle, is riveted
to the blade tips, increases their stiffness,
keeps them in proper distance and closes
the channels of the rotor, thereby reduc-
ing windage losses. The glands at each

468

POWER

September 26. 1911

end are also fitted with labyrinth pack-
ings, the clearances of which are adjust-
able in the same way as those between
the diaphragms of the impulse section
and the rotor drum. These glands are
packed with the steam e.xhausted from
the governor relays, which is admitted to
the annular channel shown round the

Drum-'' Uoubie Caii\int^ Foundation
Foundation Ring Strip Ring ''•'■'■

Fig. 4 Blahe Att.'vchment; Left, Im-
pulse; Right, Reaction

center of each gland. In order to prevent
troubles arising from differential expan-
sion of the rotor and of the casing, the
gland bush at the low-pressure end is
itself adjustable in the axial direction.
The clearances here are adjusted with
the turbine running, after which the bush
is locked in place. When cold the clear-
ances here naturally increase, but with
the rotor warm and running they are so
small that there is very little gland leak-
age. For details of blade attachment, see
Figs. 4 to 7.

In some turbines, glands with adjust-
able clearances are employed at the high-
pressure end only, larger and nonadjust-
able clearances being used at the low-
pressure end. This arrangement has, how-
ever, the disadvantage that the steam lost
by gland leakage becomes at low loads a
very considerable fraction of the total
steam passed through the turbine. On a
2000-kilowatt turbine the loss at the low-
pressure gland alone may thus amount
to 500 pounds per hour, or about 5 per
cent, of the total steam supph' at quarter
load. A 600-horsepower Melms & Pfen-
ninger turbine, built by the firm of Breit-
feld, Danek & Co., in Prague, whose
packing consists of 18 labyrinth cham-
bers of the kind shown in Fig. 8. has a
clearance when cold of 0.008 inch, which
increases to 0.01 inch during operation.
Hence with a diameter of 96 inches the
clearance area through which leakage
may occur is

(96 X •^ X 0.0 n — 0.46 = 2.56
square inches
The smallness of this area and the large-
ness of the number of labyrinths em-
ployed make leakage losses through
gland packings a negligible quantity.

The main journals of the turbine shown
measure 7.1 inches in diameter by 14.96
inches long. The bearings are of white
metal in spherical-seated cast-iron bushes,
and are lubricated with oil under pres-
sure in the usual way. Provision is also
made for the water cooling of these bear-
ings, but this really is only in the nature

of a standby, since the oil draining away
from the bearings is passed through the
cooler, shown to the left in Fig. 1, before
being pumped again into the bearings.
The temperature of the latter, when the
turbine is running, is normally not more
than 105 to 120 degrees Fahrenheit. The
thrust block is of the pattern usual in
reaction turbines, the upper and lower
halves being independently adjustable in
the axial direction, so that by moving
the one or the other by the micrometer
screws fitted, the axial clearances of the
labyrinths and diaphragms can be ad-
justed. At its outer end the shaft car-
ries an emergency governor. Should the
speed ever become excessive, the pivoted
arms fly out, thrusting to the left the
small central spindle, which operates a
knock-out gear, releasing the spring-op-
erated shutoff valve, shown below the
turbine at /, Fig. 1.

This valve is of the single-beat type,
and constitutes also the main steam stop
valve, being operated by bevel gearing
as indicated in Fig. 2. The spindle is
screwed and works in a nut formed in
the bushing shown at H. This bushing is
normally locked against movement in the
axial direction by stops. By means of
the emergency governor acting through

ment of the weights controls the position
of the eccentrics which govern the valves
admitting the exhausting steam from the
relay cylinder shown above the main gov-
ernor valve in Fig. 1. The throw of the
eccentrics is further adjustable by the
handwheel shown on the left in Fig. 3,
thus affording a means by which the num-
ber of revolutions per minute of the tur-
bine shaft can be speeded up or down.
Provision is also made for speeding the
turbine up or down from the switchboard
by means of a small motor driving the
worm and wheel shown in place in Fig.
3. At the opposite end of the transverse
shaft an oil pump is fitted, and beyond
it a hand pump used for priming the
bearings with oil in starting up.

The arrangement of a turbine as fitted
in place at Riga is shown in Figs. 9 and
!0. The output of the Riga unit is 1700
kilowatts, and the short length of the tur-
bine as compared with the generator is
very noticeable. The condenser is. as is
usual, arranged immediately under the
turbine. The inlet measures 40x27'^
inches. A large gate valve is provided
for cutting out the condenser when it is
necessary to run the turbine noncondens-
ing. The main steam pipe is arranged
below the floor level and is fitted with a

Fig. 5. Impulse Blades

Fig. 6. Guide Blades

Fig. 7. Reaction Blades

gear teeth the bush can be so rotated
as to clear these stops, and can then
move axially. thus allowing the valve to
close under the combined influence of the
steam pressure and the spring showm in
position around the valve spindle in Fig.
2. From valve / the steam travels through
two pipes arranged symmetrically on both
sides of the turbine to the governor valve
F. The form of the casing is thus sim-
plified and becomes free from harmful
strains which otherwise would occur
owing to unequal heating. In order to
retain the impurities the live steam has
to pass a sieve before entering channel
D and the blades.

Throttle regulation as employed in the
Melms & Pfenninger turbine is essential-
ly the same as in all Parsons turbines.
The ordinary governor is mounted on a
transverse shaft, as indicated at J, Fig. 3,
which rotates at some 200 revolutions per
minute. It consists of spring-controlled
weights sliding in guides, and moving in
or out as the speed, and consequently the
centrifugal force, varies. By sliding col-
lars and bell cranks the movement of
these weights is transferred to the relay
valves. In the present case the move-

separator as indicated. The circulating
and air pumps, shown in plan in Fig. 9,
are both motor driven.

For small machines up to about 500
kilowatts, the type of turbine illustrated
in Fig. 1 1 is supplied, particularly where
space is cramped and low rotary speeds

Fic S. Labyrinth Chambers

are required. There is a demand for a
machine of 300 horsepower running at
2000 revolutions only, and for 100-horse-
power turbines running at but 3000
revolutions. These low rotary speeds are
best secured by at least a partial adoption
of the principle of velocity compounding.
In the machine illustrated the high-pres-
sure end is constructed on what is com-

September 26. 1911

POWER

469

Fir.s. 9 AND 10. Plan and Elevation ofTurbine Installed at Rica

monly known as the Curtis principle. It
consists of a single wheel carr>'ing three
rows of moving blades between which
are two rows of fixed blades, these latter
extending only partially around the cyl-
inder. The steam enters the cylinder
through the symmetrically placed sets of
nozzles, from which it issues at a high
velocity, and then, without further change
of pressure, passes on through the suc-
cessive rows of fixed and moving blades.

Though the efficiency of a three-stage
velocity-compounded wheel is only about
three-quarters of that possible with a sin-
gle wheel doing the same work, it will
develop this efficiency at a blade speed
equal to between one-sixth and one-
seventh that of the steam, while with a
single wheel to get the best efficiency the
blade speed should be between one-half
and one-third that of the steam. Run at
one-sixth the velocity of the steam, a
single wheel will develop only three-
quarters as much power as a three-stage
velocity wheel run at the same speed,
so that the arrangement has great ad-
vantages when a low speed and compact-
ness of design are the essentials.

In this type of turbine the drum con-
sists of two parts riveted together, the
high-pressure part with its cone-shaped
hub being keyed on to the shaft, while
the hub of the low-pressure part lined
with a bushing slides on a thickened
portion of the shaft. The interior of the
drum is heated by steain, there being a
tube on the high-pressure end for drain-
ing the condensate into the exhaust space.

The nozzle block shown in Fig. 12 is
made of Siemens-Martin steel, being in-
serted into the turbine casing and closed

Fir,. II. Melms & Pfennincer Turbine »f .SOO Horsei'"<aip (,M■^rITY

!70

POWER

September 26, 191 1

by a cover on the side. For capacities
of from 150 to 400 kilowatts four to six
nozzles are provided in one chamber,
while in a second chamber are two noz-
zles for higher loads. By removing the
cover all nozzles can be inspected at
once. The construction of the stuffing
boxes is the same as the one in the
other type previously described, with
the difference that live and not exhaust
steam is used for packing in case that

Overload Valve

Fig. 12. Nozzle Block

at varying boiler pressures, governing by
oil under pressure instead of by steam is
resorted to. Both the main steam and
the main governing valves are located
side by side on top of the turbine cas-
ing. The valve shown to the left in the
longitudinal view of Fig. 11, is at once
the main stop valve and the emergency
valve, being tripped by a special gov-
ernor in case of a runaway. The main
governor valve at the right is operated
by an oil relay controlled by a governor
on the transverse shaft. This valve is
shown in detail in Fig. 13. The distribu-

piece with the main casing, and rest on
a rigid foundation frame.

The following is the resume of a test
recently made by Professor Schroter, of
Munich, on a 200-kilowatt turbine built

during the test being in the position
planned for their final erection in the
power station.

The peculiarity of the condensing plant
is that one condenser is so arranged that

TESTS (IF .\ 20U-KII,OV. ATT .\;i;i..\LS i PFE.\.\I.\GER TCHBI.NE

-No. of ttst

Ixjad in pi-r ccm. of full load

Duration of test in minutes

(.Absolute pressure in f Pressure
pounds per scjuare Temperature,
inch and temperature ) Temperature
deg. F. at the turbine saturated steam
inlet [ Superheat

Inches of mercury

.■\bsolute pressure in
pounds per square
inch and temperature
deg. F\ at t he exhaust
pipe

Electrical and effective
power

Condensed-water data.

per

Pressure in pound:

per square :nch .
.Saturation tem

perature

Barometer

Per cent, of the

absolute vacuum
Revolutions

minute

\'oltage

.■\mperes. . . .
K i 1 o w a 1 1 1

switchboard
Electrical power in

brake horsepower.
Efficiency of gen

erator

Effective brake

horsepower

Total in pounds .
Duration in min-
utes

Condensed water (in

pounds per houri
Condensed water

per kilowatt-hour
Condensed water

per brake horsi

power per hour .

24.97
163.5
J78.8

113.8-
1.23

o.6o;

8r> . s

.3022
241.2
10S3.3

2177
24. 9^

.5230
20.0:

100

60.28

446

360
88
1.04,

0 . .508

306
4360

4340
21.02

13.43 14.1.5

_3_

4
50

25

45.35
158.5
441

44.15
1.59.5
408.5

42.32
160.7

382

362
79.3

362.5
46

368
14

0.88

0.83

0.855

0.431

0.409

0.419

nches

73.7

74 3

96.9

97.1

97

3025
-> 43 6
521

3022
240.7
423.2

3025
243.1
216.4

151.2

101.8

52.6

205.5

138.4

71.5

89

85

74.7

230.8

162.7

95.7

2620

1960

1308

45.35

44.15

42.32

3475

2660

1850

22.9

26.15

35.2

15.28

16.35

19.35

0.449
76.6

for the Imperial Torpedo Shops in Fried-
richsort, near Kiel. In view of the fact
that most builders are somewhat reluctant
to publish the results of tests with small
turbine units, because the leakage and
other losses are proportionately of more
importance in the smaller sizes and the
steam consumption is higher than that of
the larger, this test is of special interest.

either turbine or both can exhaust into
it. But during the test the exhaust branch
connected to the turbine not in use was
hermetically closed. The air pump and
circulating pump had electric drive, but,
as is usual, the work absorbed by these
pumps is not included in the results.

The power output of the direct-current
generator was absorbed by a water

200

250

Fig. 13. Govkrnor Valve and Oil Relay

Fig.

50 100 150

Kilowatt Output

14. Curves Show Actual Values Obt\ined in Tests

tion of the steam to these valves and
their connection with the overload valve,
as well as the conduction of steam to
the nozzle chest, is shown in Fig. 12. The
turbine casing is divided horizontally and
carries a safety valve on the low-pres-
sure side. The bearings are of the con-
centric-sleeve type, being cast in one

The object of the test was primarily
to measure the economic efficiency of
the turbine at various loads. Shortness
of time did not allow arrangements for
the observation of other data of scientific
interest, as the turbine was dismantled
the next day for delivery. The plant
consisted of two turbines, both of them

rheostat, which worked well and per-
mitted a regulation of the load with but
small variations. The voltage was meas-
ured with a standard instrument belong-
ing to the technical high school, while
the switchboard ammeter was compared
with the standard instrument of the city
electric-power works laboratory. The

September 26, 1911

POWER

471

pressure and temperature were measured
with the usual instruments, the vacuum
with a mercur>' column in terms of the
percentage of the barometric hight. The
revolutions were obtained by timing 200
strokes of the eccentric rod 'vith a one-
tifth-second stop watch.

The condensed water was measured in
tanks belonging to the outfit of the test
room, which were carefully gaged by
ing with weighed quantities of water,
-. with due regard to the temperature.
\ constant time interval between the
F>'-Ssage of the water level past each 50-
;iter mark showed without doubt when
the equilibrium aimed at before each test
V as obtained. In the accompanying table
results only the average of the read-
-? is given. The temperature of the
perheated steam is not constant, as is
usual with built-in superheaters, the tem-
perature varying with the change of the
load, although great pains were taken to
keep the temperature constant. The nor-
mal steam temperature required at the
inlet is 446 degrees Fahrenheit, but since
in actual service constant steam tempera-
ture can no more be obtained than in
this case, a calculation of the results re-
duced to a constant temperature was not
made. The vacuum showed only small
\ariations with a change of the load, and
no allowance was made in the calcula-
• on for these variations; the high degree
\acuum of the condensing plant is to
noticed.
In calculating the effective work in
brake horsepower, the results of tests
r rformed in the testing department of
Berliner Maschinenbau Aktiengesell-
ift, vorm. L. Schwartzkopff, Berlin,
were used for estimating the efficiency
of the generator. The data given by
the above company with regard to the

'^ S'f'eam

Convenient Oil Pumps

The illustration, Fig. 1, shows a home-
made oil pump which saves considerable
manual labor and works to perfection.
It consists of a brass pump cylinder.
One end is screwed into a tee connec-
tion and the other end is fitted with a
packing nut for the plunger. To the
tee connection two nipples are secured
upon which two check valves are placed
as shown. One acts as the suction valve
and the other as the discharge valve
of the pump. The discharge valve is
fitted with a pet cock so that the line
between it and the oil tank can be re-
lieved of air and oil if desired.

To the check valve a tee connection
is fitted by means of a nipple and an air
chamber secured to the side outlet of
the tee. This air chamber is made of
an old copper float soldered to a short
nipple. The pipe extension beyond the
air chamber is connected to a hose which
can be inserted in a barrel and the oil
may be pumped into the oil tank located
in the engine room above; the pump and
check valves are in the basement. The
pump derives its motion from the wrist-
plate of the exhaust valves on the steam
engine, so that the pump is always in
operation and ready for use so long as
the engine is running. The pipe C is
for the purpose of blowing steam on the
check valve in cold weather to heat the
oil and facilitate its flow.

In Fig. 2 is shown a second pump that
is operated from the same wristplate

To Exhaust
Wrfst Plate

i

1-

■ ¥

:^__ -_ ^.

U-

To Oil Barrel

resistances of the generator were used to
calculate the work supplied to the gen-
erator at no load with the field magnets
excited. And with these data and the
interpolation of the graphic representa-
tion of the curve of steam consumption
per brake horsepower-hour the steam
consumption of the turbine with no load
was obtained with considerable accuracy.
The graphic representation. Fig. 14, of
the main results, both as to kilowatts and
to effective power, shows throughout the
regularity of the data.

Fig. 1. Oil Pump for Pumping Oil from
Barrel Into Tank

and is used to lubricate the condenser
located in the basement.

Attached to one side of the pump is a
pipe which connects with a small oil
reservoir to which is fitted a sight glass.
The discharge of the pump is connected
to the steam pipe running to the con-
denser. A check valve is inserted to
prevent the steam from blowing into the
pump.

The feed of oil is regulated by means
of a needle valve in the sight glass, and
as the oil flows to the pump cylinder

the plunger in its downward movement
forces the oil into the steam pipe leading
to the condenser. As soon as the plunger
has dropped below the inlet pipe the
oil cannot, of course, be forced back
into the oil tank.

This device saves many steps from
the engine room to the condenser to see

Fig. 2, Condenser Llbricatinc PuAtP

that it is being lubricated, as it is only
necessary to note the flow of oil through
the sight glass.

A pertinent illustration of the effect
of high temperature upon cast iron was
given in the course of the discussion on
a paper on "Superheated Steam in
iVlarine Engines" recently read before
the Northeast Coast Institute of Engi-
neers. One of the speakers mentioned
as a well authenticated fact that where
superheated steam was used in turbines
the growth of the turbine casings at the
dummy end had been in some cases so
marked that the steam consumption was
increased to such an extent that new
dummy plates in many rases have had to
he put in. The same speaker also men-
tioned another effect on cast iron pro-
duced by exposure to high superheat
for several years, the iron occasionally
1 ecoming so deteriorated that it can be
CMi with a knife like plumbago, which in
appearance it very much resembles. This
kind of decay is not unfamiliar to tho.sc
who have had experience of the working
of economizers, the upper portions of
which are sometimes found decayed in
l.iis way. Investigation has shown that
it gencrnlly occurs in installations where
the apparatus has been exposed to high
temperatures and has not been kept filled
with water. No satisfactory explanation
has. wt believe, been offered to account
foi this chemical change, though it has
obviously a practical bearing, and we
suggest the matter as one well deserv-
ing of research by chemists and metal-
t'lrgists. — The Mechanical Engineer.

POWER

September 26, 1911

Design of Steam Power Plants

Condensers

In power plants having water available
in sufficient quantities for condensing
purposes, the horsepower of the main
engines may be increased and the fuel
cost per horsepott-er materially reduced
by installing efficient condensing appa-
ratus. The real saving made possible
by the installation of condensers de-
pends on the cost of fuel, cost of con-
densing water, cost of pumping, upkeep,
repairs, etc., on the condensers, and the
cost of boiler- feed water.

The main object of a condenser is to
remove a large part of the back pressure
from the exhaust side of the engine pis-
ton, thus increasing the power of the
engine without increasing the fuel con-
sumption, or by decreasing the fuel con-
sumption with the same power output.
In noncondensing engines where the
steam exhausts direct to the atmosphere,
at least, the pressure of the atmosphere
must act against the exhaust side of
the piston, but in practice the back pres-
sure is seldom less than 17 or 18 pounds
absolute; whereas the back pressure act-
ing against the exhaust side of the pis-
ton of a good condensing engine is often
as low as 2 pounds absolute.

If an engine is running without a con-
denser, at a mean effective pressure of,
say, 50 pounds per square inch, and a
condenser is added, removing, say, 14

By William F. Fischer

Ilcjus to be considered in
the selection of a condenser;
saving effected, and method
of calculating necessary cir-
culating water.

added
formu

where
G

A
R

S

The re
engine
lows:

by the condenser, the following
la may be employed:
^^ ARS
33,ooo

= Gain in horsepower due to the

condenser;
= Area of piston in square inches;
=: Reduction in back pressure in

pounds per square inch;

= Piston speed in feet per minute.

duction in back pressure R on the

piston may be estimated as fol-

= «-(^)

where
B

Absolute back pressure in
pounds per square inch on
the engine piston when run-
ning noncondensing;

steam, and the mean effective pressure
will remain constant.

Suppose cutoff occurred at !4 stroke
when running noncondensing and at ]4,
stroke when running condensing, neg-
lecting clearance, the saving in steam per
stroke is the difference between J4 and
Yd the piston displacement, or

0.2S — 0.166

X 100 = 33 Per cent.

O.J5 ■'■^ '^

Neglecting friction and other losses,

the theoretical mean effective pressure

may be determined as follows:

(l + hyp, log, r)

M.e.p. = P X

-P

where
P

Absolute initial pressure in
pounds per square inch;
p =^ Absolute back pressure in
pounds per square inch;
and

r = Ratio of e.xpansion =

Length of stroke -\- clearance
Distance to cutoff -f- clearance
Table 1, showing the mean pressure
per pound of initial pressure, with dif-
ferent clearances and cutoffs, is in con-
densed form as taken from "The Steam
Engine Indicator," by F. R. Low.

Assume a simple noncondensing en-
gine having a clearance of 6 per cent.
and cutting off at 0.25 of the stroke. Let
the steam pressure at the throttle be 150
pounds absolute and the back pressure

T.^BI.E 1. MEAN PRE.-^srRE PER POUND OF INITIAL, WITH DIFFERENT CLEARANCES AND POIXT.S OF CUTOFF

PERCENT.tGE OF ClE.UIAXCE

Cuto

T in Frac-
s of the

tior

Stroke

0

1

1 .5

2

2.5

3

3.0

4

4.5

^

0.0

6

6.5

7

A

0.1

0.3303

0.3439

0.3505

0.3568

0.3630

0.3690

0.3750

0.3808

0.3864

0.3919

0.3974

0.4027

0.4076

0.4126

0.1 2,T

0.:iS49

0 3966

0.4023

0.4078

0.4132

0.4187

0.4237

0.4287

0.4338

0.4386

0 . 4433

0.4480

0.4527

0.4571

i

0 167

0.4662

0.4757

0.4802

0.4844

0.4890

0.4933

0.4973

0.5014

0..5056

0.5096

0.5134

0.5173

0.5210

0.5245

■I

0.188

0.5013

0 . .5097

0.513S

0.5181

0.5217

0.5259

0.5295

0..5332

0.5367

0.5405

0.5440

0.5474

0.5511

0.5546

V

0.20

0.521U

0 . 5298

0.5336

0.5376

0.5414

0.5449

0..54S2

0.5517

0.55SS

0 5623

0 . 5656

0.5687

0.5716

0.25

0.5966

0 6025

0.6059

0 6090

0.6120

0.6148

0.6174

0.6207

0.6229

0.6258

0.6286

0.6312

0.6336

0.6359

to

0.30

0.6609

0 . 6663

0.6684

0.6712

0.6729

0 6755

0.6779

0.6803

0.6825

0.6845

0 . 6864

0.68S2

0.6911

0.6927

i

0.333

0.69SS

0.7029

0 7047

0 7076

0 . 7092

0 7106

0,7132

0.7144

0.7168

0.7190

0 7212

0.7219

0.7239

0.7'57

0.375

0.7433

0.7458

0.7476

0 7494

0.7510

0.7525

0.7539

0.7569

0.7582

0.7593

0.7603

0.7630

0.7639

0.7646

i

0 40

0.7665

0.7691

0.7719

0.7729

0.7738

0.7765

0.7772

0.7778

0.7802

0.7806

0.7829

0.7831

0.7853

0.7S74

f

0.50

0,8466

0 . S484

0 8492

0 . 8503

0.8513

0.8522

0.8530

0.8539

0.854S

0.8556

0 . 8565

0.8.573

0.8582

0.S590

?

0.60

0.9064

0.9076

0 . 9081

0.9087

0.9092

0.9097

0.9102

0.9107

0.9112

0.9117

0.9122

0.9127

0.9132

0.9iSo

0.625

0.918S

0.9194

0.9201

0 . 9206

0.9210

0.9215

0.9220

0.9224

0.9-'2S

0.9233

0.9237

0.9241

0.9245

0.9249

0.667

0.9371

0.9378

0 . 9382

0.9385

0.9389

0.9392

0.9396

0.9399

0.9402

0.9405

0.9408

0.9411

0.9415

0.9418

0.70

0.9497

0.9502

0 9505

0,9508

0.9511

0.9513

0.9516

0.9518

0.9521

0.9524

0.9526

0.9528

0.9531

0.9533

0 75

0.9657

0.9661

0.9663

0.9665

0.9667

0.9668

0.9670

0.9672

0.9674

0.9675

0.9677

0.9679

0.9680

0.9682

pounds of the back pressure, the mean
effective pressure would be increased
theoretically to 64 pounds and the power
of the engine would be correspondingly
increased.

If the work done by the engine, after
installing the condenser, remains the
same, the mean effective pressure may
be reduced again to 50 pounds by cut-
ting off the steam earlier in the stroke
and thus effecting a saving in steam con-
sumption. Therefore, if the mean ef-
fective pressure produced by the con-
denser is known, one may readily esti-
mate the horsepower added by the con-
denser.

If it is desired to find the horsepower

V = Vacuum in inches of mercury
(referred to a 30-inch barom-
eter) produced by the con-
denser.

Saving in Steam Due to Condenser

Generally speaking, a noncondensing
engine requires from 20 to 30 per cent,
more steam per horsepower-hour than a
condensing engine of the same power.
If a condenser be added to a noncon-
densing engine of, say. 200 horsepower,
running at 100 revolutions per minute
and the load and speed be kept the same
after adding the condenser, the governor
will produce earlier cutoff, thus lower-
ing the mean forward pressure of the

17 pounds absolute. It is also assumed
that the initial pressure in the cylinder is
the same as the pressure at the throttle.
In the column headed "6 per cent, clear-
ance," opposite '4 cutoff, the mean pres-
sure per pound of initial pressure will
be found to equal 0.6312. This multiplied
by the initial pressure is

150 X 0.6312 = 94.68 pounds
which is the mean forward pressure of
the steam. Subtracting the absolute back
pressure,
94.68 — 17 = 77.68 pounds per square

inch
as the mean effective pressure on the
piston.

September 26, 1911

POWER

473

Let it be required to find an approxi-
mate point of cutoff which will maintain
the same power of the engine when run-
ning condensing, with a vacuum of 26
inches, it being understood that the speed
and load, and consequently the initial
and mean effective pressures, remain the
same.

Dividing 26 inches of vacuum by 2.04
gives 12.7 pounds per square inch, and
subtracting this from the atmospheric
pressure leaves 2 pounds as the approxi-
mate absolute back pressure on the pis-
ton. The mean pressure ratio for the
foregoing conditions may be found by
adding the mean effective pressure to the
absolute back pressure and dividing by
thfe absolute initial steam pressure.

Substituting the actual values

-7.68 4-:^^ .,^,
150 ■^-'

as the mean pressure ratio required.

Referring again to the table and fol-
lowing down the column headed "6 per
cent, clearance." 0.5.^12 will be found to
be between the values 0.5173 and 0.5474.
Taking 0.5474 as the nearest figure in
the table, it is found to correspond to a
cutoff of 3/16, or 18.8 per cent, of the
stroke.

The approximate saving in steam is

rt -»r r» iSR

X 100 ^ 24.8 per cent.

0-5

due to adding the condenser and thereby
shortening the cutoff.

If the saving in fuel is assumed to
be In direct proportion to the saving
in steam the condensing engine in this
case will require 24.8 per cent, less fuel
than the same engine would when run
noncondensing.

Gain in Ther.mal Efficiency

The gain in thermal efficiency due to
adding a condenser may be calculated as
follows: Let

£ = Thermal efficiency of the en-
gine;
T, — Absolute temperature at which
the steam is received by the
engine;
T: — Absolute temperature at which
the steam is exhausted from
the engine.
Then for a perfect engine,
,- 7-, - T,
T,
The efficiency of an engine may be
increased by raising the boiler pressure
and thus Increasing 7", or by reducing the
back pressure by adding a condenser,
thus decreasing T,, or by doing both. It
is evident from the formula that by re-
ducing the back pressure a much greater
gain in efficiency results than by raising
the boiler pressure a like amount. This Is
shown in the following examples:

Suppose a noncondensing engine Is
supplied with steam at I. SO pounds ab-
solute, as In the previous example, and
exhausts at 17 pounds absolute. The

absolute temperature 7":, corresponding
to 150 pounds, is

358.5 -f 461 = 819.5 degrees Fahrenheit
and the absolute temperature 7",, corre-
sponding to 17 pounds absolute pres-
sure, is

219.4 + 461 = 680.4 degrees Fahrenheit
Hence the thermal efficiency is

_ 819.5 — 680.4

E = — 2_i 2::= 0.17

819-5
or 17 per cent.

Now suppose the boiler pressure be
raised from 150 pounds absolute to 200
pounds absolute, and the exhaust pres-
sure kept the same. Then the absolute
temperature 7", corresponding to 200
pounds absolute, is 842.9 degrees Fahren-
heit, and the absolute temperature T:,
corresponding to 17 pounds absolute, is
680.4 degrees Fahrenheit. Hence, the
thermal efficiency is

842.9 — 680.4

84-' .9 ^•'

or 19.3 per cent.

Suppose instead of raising the boiler
pressure a condenser be added, reducing
the back pressure from 17 pounds to
2 pounds absolute. The absolute tem-
perature 7"., corresponding to 2 pounds
absolute, is 587.15 degrees Fahrenheit,
and the absolute temperature T, as al-
ready found was 819.5 degrees Fahren-
heit. In this case the thermal efficiency
would be

8.9 5-587-.S^„_,g
819-5
or 28.3 per cent.

From the foregoing it is evident that
by lowering the exhaust pressure 15
pounds a much greater gain in efficiency
is effected than if the boiler pressure had
been raised 50 pounds. Owing to the
fact that part of the heat is lost by radia-
tion, conduction, cylinder condensation,
leakage, imperfect valve action, etc., the
efficiencies herein shown are never
realized in the actual engine; the cal-
culations apply to a perfect engine only
and are merely for comparison.

It should be kept in mind that com-
pound condensing engines are usually so
designed that the exhaust valves open
when the back pressure is from 6 to 8
pounds absolute in the low-pressure cyl-
inder. This is due to the fact that it is
not practical to proportion cylinders to
take care of the excessively large vol-
umes of steam produced by expansion
to the lower pressures. By consulting
the steam tables one can readily see
how rapidly the volume increases as the
pressure decreases below the figures
given. If the exhaust valve opens at,
say, 6 pounds absolute (corresponding
to a vacuum of approximately 18 Inches).
It Is readily seen that a higher vacuum
In the condenser will serve only to
diminish the back pressure on the en-
gine piston without afTeciIng the com-
pleteness of expansion in the low-pres-
sure cylinder. The exhaust steam after

leaving the engine cylinder will expand
in the exhaust pipe and condenser from
release pressure down to condenser pres-
sure.

Even if it were found practical to ex-
pand to a much lower pressure in the
low-pressure cylinder, the low tempera-
ture of the exhaust would cool the cyl-
inder walls to such an extent as to cause
a very rapid increase in cylinder con-
densation.

Cooling Water for Condensers
In the previous examples no account
was taken of the quantity of cooling
water required to condense the steam.
In any case, the cost of supplying the
condensers- with cooling water, and the
cost of operating the dry-vacuum pump
and hotwell pump, the cost of upkeep
on the condensing apparatus and the in-
terest and depreciation should all be
taken into account when figuring the
actual saving due to a condenser.

As the cost of pumping the cooling
water depends upon the quantity pumped,
and this in turn depends directly upon
the amount of heat imparted to each
pound of water leaving the condenser, it
is desirable that the discharge tempera-
ture of the cooling water be close to
that of the steam. Also, if water avail-
able for condensing purposes is limited,
or in localities where the temperature of
the water is very high during a large
part of the year, it is advisable to dis-
charge at as high a temperature as pos-
sible without decreasing the vacuum be-
low the desired figure. However, where
water is plentiful there is a tendency
to use an excess to take care of maxi-
mum-load periods, thus producing a com-
paratively low discharge temperature.

Where the condensing apparatus is im-
properly designed to suit the given con-
ditions it may be found necessary at
times to operate at a much lower vacuum
during the summer months than would be
necessary if the condensers were prop-
erly selected.

The approximate qua;itity of condens-
ing water required to condense one pound
of steam with a jet condenser may be
obtained from the following equation:

Q V (T - /) - (W -^ 32) - r
where

Q :~ Pounds of water required to
condense one pound of steam;
T =: Temperature of discharge water,
leaving the condenser, in de-
grees Fahrenheit;
/ = Temperature of the injection
water entering the condenser,
in degrees Fahrenheit;
and

H = Total heat above 32 degrees
Fahrenheit in one pound of
steam to be condensed.
Transposing In the equation.
{H + .^2) - T
t- - ^T- I)

From the foregoing it Is readily seen

474

POWER

September 26, 1911

that the quantity of water required de-
pends chiefly upon its initial temperature,
which may vary from, scy, 40 degrees
Fahrenheit during the winter months to
80 degrees or more during the summer
months, depending upon the location of
the plant and the source of water supply.

Table 2 is based on the new steam
tables by Marks & Davis and is given
here as a guide in figuring the condensing
water required per pound of steam in
condenser installations. In column I is
given the vacuum in inches of mercury
referred to a 30-inch barometer. Column
2 gives the corresponding absolute pres-
sure in pounds per square inch, above
vacuum. Column 3 contains the corre-
sponding temperature of the mixture of
steam and water at the condenser pres-
sure and in column 4 is given the total
heat in one pound of steam at the given
pressure, to which has been added 32
B.t.u.

For example: With a vacuum of 28
inches of mercury referred to a 30-inch
barometer {H + 32), is found from
Table 2 to be 1137 B.t.u. Substituting
in the formula,

T-l

for a 28-inch vacuum. In column 5 the
volume in cubic feet per pound of steam
is given, and in column 6 the weight of
one cubic foot of steam at the given
pressure and temperature corresponding
to the given vacuum.

In determining the proper value to sub-
stitute for T, the temperature of the dis-
charge water, care should be taken to
allow a suitable drop between the steam

Surface Co.ndensers

When estimating the quantity of water
required per pound of steam in surface
condensers it is custoinary to take into
account the temperature of the condensed
steam; that is, the hotwell temperature.

Hence for surface condensers

Q =

(H 4- .V) - Tc
T t

where Tc equals the temperature of the
condensed steam and Q, H, T and t
represent the same quantities as in the
formula for jet condensers. In the or-
dinary surface condenser of the single-
or double-flow type, Tc may be taken
from 10 to 20 degrees lower than the
temperature due to the vacuum.

How the Engine Was
Wrecked

BV W. F. BURDICK

On a recent morning, in the mill where
the writer is employed as chief engineer,
a center-crank engine, 15x16 inches, op-
erating under 150 pounds pressure at a
speed of 150 revolutions per minute, sud-
denly began to make strange noises at
the head end of the cylinder. The en-
gineer tried to locate the noise, but failed,
and the pounding so increased that it
jarred the engine severely.

As he was afraid to take any further
chances, the engineer shut down. He
thought that when the engine was stopped
he could locate the cause of the pound-
ing, but just as he closed the throttle
valve the engine went to pieces. The

T.\BLE :>. Il.\

lA I'Uojr WHICH TO detkhmixe con

HENSIXC \V.\TI

:i! UK(.iriUEI>

PEK POIND OV STE.\M

Vacuum in

Inclh's of

MtTcurv Re-

.\l)solute Pres-

ferred to a.

sure in Pounds

Temperature

Volume in Cubic

per Square
Inch

in De|rree.s

(H-f-32)

Feet per Pound

Fahrenheit

B.t.u.

of Steam

per Cubic Foot

29 . 82

0 . 0!)

32

1105

3294

0 0003

0 , 2.".

.59

1117

l->49

0.0008

0 .'lO

1127

636 . 8

0 0016

(1,74

92

11. 52

442,2

1 0(1

102

1137

331.5

0.0030

I 2-1

109

1140

'>72 9

27.00
26.50

• 1 .il

116
121

1143
1145

225. S
197.9

0.0044

1 ,99

126

1147

173.9

n 0057

130

1140

157.1

2 17

134

1 150

142.2

0 0070

1 1 52

128,9

141

1153

119,9

0 . 0083

1155

111 6

3 4.5

147

1156

104.0

0 0096

1157

97.0

0 0103

3 96

152

11 58

93,0

0 0108

155

1 1 59

.S6,4

0.0116

157

1160

82 6

1 70

159

1161

78.0

20.00

1 90

162

1 1 62

73.8

,-> SO

169

1165

63.3

16.00

0 .S.l

176

1 1 BS

54 5

0.0183

182

1171

48.12

I) 0207

26 79

0.0373

in the condenser and the temperature of
the discharge water. In practice the
temperature of the discharge water is
assumed to be 15 degrees lower than
the steam temperature and it is customary
to allow for 10 per cent, more water than
the estimated quantity where actual con-
ditions are unknown.

frame and shaft governor were the only
parts left intact.

The strap on the wristpin end of the
connecting rod broke first (see A, Fig.
I), but it did not open enough at first
to free the box and crosshead. As the
clearance between the piston and cylinder
head was only .j^ inch, the opening of

the strap allowed the piston to strike
the cylinder head, thus causing the
pounding.

Perhaps one minute elapsed from the
time the pounding was noticed until the
accident. Every time the engine took
steam at the crank end the strap was
opened wider until finally it broke loose
and separated the piston rod and cross-
head from the connecting rod, knocked
out the cylinder head and broke off every
stud which held the head to the cylinder.

The cylinder head was afterward found
28 feet away from the engine, and

Fir. 1. Connecting Rod

as the piston was out of the cylinder
about 6 inches it would have accom-
panied the head if the crosshead had not
brought up against the opposite head.
The spool pieces which supported the
upper crosshead guides were also broken
and the bolts were so badly bent and
twisted as to be useless.

As the momentum of the machinery
had kept the crank shaft moving, it threw
the connecting rod to the front part of
the frame. When in that position the
counterbalance could not pass, and it

Fig. 2. Flywheels of Wrecked Engine

therefore broke off the straps of the
crank-pin boxes and sheared off the bolts
and key as well as the counterbalance
(see Fig. 2>.

Though the counterbalance weighed
460 pounds, it was found tightly wedged
between the frame and the flywheel, one
spoke of which was broken. The con-
necting rod was discovered in front of
the engine, where it had fallen after
breaking loose from the crank pin.

As this engine was placed out in the
factory, with its cylinder head just clear-
ing a passageway where the help were
almost continuously passing to and fro,
it was remarkable that no one was hurt.
The engine only was damaged.

September 26. 191 1

POWER

Using Compressed Air in Steam Hoists

One of the most unsatisfactory fea-
tures of compressed-air practice up to the
present time has been in the inadequacy
of the means provided for storing the air
between its compression and its use, or
for maintaining a full and constant pres-
sure under a varying rate of consump-
tion. It may be said that compressed air
wherever employed, is always used more
or less intermittently, and never at any
constant rate except in cases where the
entire output of a compressor of a large
ccmpressing plant is employed in a single
water-pumping operation.

The air receiver usually provided with
an air compressor has a total air capacity
not exceeding the output of the compres-
sor for a single minute, so that if the
compressor stops or is slowed down to
below the capacity to supply the con-
sumption the pressure instantly begins to
fall. To insure somewhat reliable main-
tenance of pressure and volume it is the
practice to provide a maximum com-
pressing capacity somewhat in excess of
the maximum demand and then to auto-
matically reduce the speed of the com-
pressor as the rate of consumption dimin-
ishes. Even this arrangement usually
does not completely satisfy the fluctuat-
ing requirements, and so we have various
unloading or choking contrivances which
will still more reduce the output without
actually stopping the machine. How-
ever satisfactory the results thus obtained
may be. it is evident that they are secured
only by more or less complication of ap-
paratus and a sacrifice of the essential
conditions of power economy in the run-
ning of the machine.

A magnificent opportunity for the solu-
tion of this air-power storage problem
opened to the engineers of the Anaconda
Copper Mining Company, at Butte. Mont.,
when it was proposed to find a cheaper
means of driving their great mine hoists
than by the use of steam. There were at
Butte 25 large steam-driven hoists with
an aggregate capacity of 40.000 horse-
power, but the service required of the
hoists was so intermittent, and the actual
time of working of each was so short,
that It was estimated that 4000 horse-
power in constant operation would be
sufficient for all the requirements, but it
was imperative that the power should be
always ready and always sufficient for
c^ch individual hoist.

The cost of steam had been about S80
per horsepower per year, while electric
horsepower per year could be had for
about S25. There were, however, serious
objections to the adoption of the electric
drive for each .separate hoist, besides the
enormous first cost of such an installa-
tion. Here, also, there could be no power
storage, so that it would be necessary ?:
limes to have current available for nearly
si! the hoists at once.

By Frank Richards

A I the Aiiaccmda copper
innies compressed air is
used to drive 25 steavi hoists
u'ltJi a)i aggregate capacity
of 40,000 horsepower, al-
though only 4000 horse-
poncr is required in co)i-
stant operation. A battery
of air receivers in connec-
tion with an open water
tank afford storage capacity
and keep the pressure con-
^ta)il.

So far as the steam hoisting engines
were concerned, they could be adapted to
the using of compressed air at compara-
tively slight cost, if only the power-stor-
age problem could be solved, so that a
constant drive of sufficient average capa-
city could be made able to take care of
the peak loads whenever they should
occur, even up to the running of all the
hoists at once. The problem has been
solved with a success and completeness
seldom surpassed in great engineering
undertakings.

The electric current which drives the
compressors is transmitted 130 miles
from the new plant of the Great Falls
Water Power and Townsite Company, at
Rainbow falls, just below the Great falls
on the Missouri river. There are three-
compressors, each with a direct-connected
Westinghouse motor of 1500 maximum
horsepower. The compressors, furnished
by the Nordberg Manufacturing Com-
pany, are two-stage machines of the high-
est class, with low-pressure cylinders 5U
inches diameter and high-pressure cylin-
ders 30 inches diameter, and a common
stroke of 48 inches. The combined free-
air capacity of the three compressor.-s I
would estimate roughly at 20,000 cubic
feet per minute (not knowing the build-
er's specifications as to speed, etc.).

Thk Aik Receivers

From the compressors the air passes
to the battery of air receivers. There are
32 of these, vertical, each 10 feet diam-
eter and 30 feet high, their combined
cubical content being, say, 70,000 cubic
feet, which, at PO pounds gaec pressure,
may be said to equal .'>0<l,00fl cubic lect
of free air. a volume which it would take
thi combined compressors nearly half an
hour to compress and deliver. This :<=

very different, to begin with, from the
less than one minute capacity of the air
receiver usually provided.

But the more important particular is
that whereas in the established and
familiar air-receiver practice, as soon as
any air is withdrawn from the receiver
in excess of what the compressor is de-
livering, or if for any reason the com-
pressor stops, the pressure in the receiver
begins to fall rapidly and constantly with
the drawing of the air, it is as different
as can be under the arrangement here
being considered. Instead of a drop of
pressure rendering the remaining con-
tents of the receiver ineffective and use-
less, the pressure is maintained and the
entire contents of the whole battery of
receivers, including the original inert
filling of air at atmospheric pressure, can
be used at full pressure and effective-
ness until the receivers are emptied. In
practice the withdrawal of the air never
goes as far as this. As these compres-
sors run all day and all night, when there
is at any time a simultaneous call for
operating an unusual number of hoists,
there is always the full capacity of the
working compressors and also the entire
contents of the battery of receivers to
draw from until the unusual and exces-
sive demand for air ceases. When there
is such an unusual simultaneity of hoist-
ing it is necessarily succeeded by a period
when the hoisting and the demand for air
are less than the compressor output, and
then the receivers are automatically filled
again.

How THE Air Pressure Is Maintained
The device by which the air pressure
is maintained in the receivers notwith-
standing the diminution of the contained
air is essentially a simple one. It is ac-
complished by the use of a standpipe
01 its equivalent, the same as in water-
works service. On a side hill at an ele-
vation sufficient to give the required gage
pressure of 90 pounds, there is an open
water tank 100 feet in diameter and 15
feet deep. A depth of 10 feet in this tank
gives a water capacity somewhat greater
than the total cubic capacity of the bat-
tery of air receivers. As 2.3 feet of
water gives 1 pound pressure, the mean
elevation of the tank above the receivers
should be

90 • 2.3 -^ 207 feet.
There is a large pipe connection from the
bottom of this tank to a horizontal pipe in
free communication with the lower ends
of all the receivers. No valves of any
kind are required, and little, if anything,
r.ecd be allowed for the friction of the
Mater in the pipes, it being free to flow in
either direction, according to the changes
of the volume of air in the receivers.
No safety valves are required, and it is
impossible to produce any pressure in the

476

POWER

September 26, 1911

leceivers greater than that due to the
head of water.

The compressed air as it is delivered
from the operating compressors does not
pass through the receivers, and, indeed,
does not enter them at all except when
the air production is greater than the
consumption at the moment, when the
surplus passes into the receivers, driving
out and up into the elevated tank some
of the water at the bottom of the re-
ceivers. When the call for air is greater
than the compressor supply then the de-
ficiency is made up by a flow of air from
the receivers, the water from the tank
displacing it.

The contact of the air with the water
does not make it any wetter, as after
compression it is quite certain to be satu-
rated with water in any case. In the ser-
vice for which this air is used, there
is no call for "dry" air, as special
means are provided for heating the air
before it enters the hoisting engines,
and moisture would be an advantage
rather than otherwise.

The plant is unique as it stands, but
in the use of the elevated tank it
sets an example which in time should
be widely adopted. For the mainte-
nance of a constant air pressure with
considerable storage capacity it seems to
recognize and fill a long persisting re-
quirement. The elevations which will
give gage pressures of 50, 60, 70, 80, 90
and 100 pounds are, respectively, 115, .
138, 161, 184, 207 and 230 feet. These
hights can, of course, be secured as well
by sinking the receivers as by elevating
the tanks, or by a combination of both
until the vertical difference is secured.

Centrifuj.^al Force- and Fly-
wheels
By H. D. Odell

While it would be a hard matter to
get a majority of operating engineers to
"acknowledge the corn," there is no doubt
in my mind that a goodly percentage
of flywheel explosions are caused by
ignorance on the part of the engineer
in not knowing how to find the safe
speed for a given wheel. To increase the
working capacity of his engines many
a man will increase the speed, taking
chances on the flywheel standing the
extra strain. In some cases this is like
putting the extra straw on the proverbial
camel's back. I have known of instances
where second-hand engines were bought
to pull generators (direct connected)
where the speed of the generators was
greater than the speed of the engines;
the engineers would say, "Guess they'll
stand it," and go ahead and speed them,
up, never figuring on the bursting speed
of the flywheel.

I know of one case where the man-
ager of a company bought a generator
in one place and the engine in another.
That he had some common sense is

shown by the fact that after contracting
for a certain type, he made arrangements
with the engine builders to have the
armature of the generator brought to
their shop and pressed on the engine
shaft. The capacity of the engine was
exactly right for the generator; he was
particular to see that no mistake was
made in the size of the shaft, in order
that the armature would fit. And he was
particular to make sure that the space
between the main bearings was sufficient
to accommodate the generator. But he
never once thought of the speed of the
generator, and the result was that the
machinery was placed and ready to run
before the oversight was noticed. Rather
than acknowledge his mistake to head-
quarters the manager gave the engineer
orders to increase the speed of the en-
gine 25 revolutions per minute. As far
as I know, nothing serious ever hap-
pened, but it was not due to good judg-
ment on his part.

Illustration of Centrifugal Force

The foregoing serves to illustrate the
importance of realizing the influence of
centrifugal force and being able to cal-
culate the safe speed for a given fly-
wheel.

If a body is fastened to a string and
whirled so as to receive a circular mo-
tion, there will be a pull on the string
which will be greater or less as the
velocity increases or decreases. Assume
that the body is revolved horizontally,
so that the action of gravity on it will
always be the same. According to the
first law of motion, a body put in motion
tends to move in a straight line unless
acted on by some other force, causing
a change in direction. When the body
moves in a circle, the force that causes it
to thus move instead of in a straight line
is exactly equal to the tension of the
string. If the string were cut, the pull-
ing force that drew it away from the
straight line would be removed, and the
body would then move in a straight line
tangent to the circle, as in the accompany-
ing figure. Since, according to the third
law of motion, every action has an equal
and opposite reaction, the force that acts
as an equal and opposite force to the

pull of the string is called the "cen-
trifugal force" and it acts away from
the center of motion. The other force,
or tension, of the string is called the
"centripetal force," and it acts toward
the center of motion. It is evident that
these two forces, acting in opposite di-
rections, tend to pull the string apart,
and, if the velocity be sufficiently in-
creased, the string will break. It is also
evident that no body can revolve without
generating centrifugal force.

The value of the centrifugal force, ex-
pressed in pounds, of any revolving
body is calculated by the following rule:
The centrifugal force equals the con-
tinued product of 0.00034, the weight
of the body in pounds, the radius in
feet Uaken as the distance between the
center of gravity of the body and the
center about which it revolves), and the
square of the number of revolutions per
minute. Let

F = Centrifugal force in pounds;
W = Weight of revolving body in

pounds;
R — Radius in feet of circle de-
scribed by center of gravity
of revolving body;
N = Revolutions per minute of re-
volving body.
Then,

F = 0.00034 W RN'
For example, we will say that the string
in the accompanying figure is 5 feet
long. If the ball weighs 5 pounds and
is revolved at the rate of 500 revolutions
per minute, what will be the tension in
the string? Using the rule just given,
F = 0.00034 X 5 X 5 X 500" = 2125
pounds

In flywheels, belt wheels and pulleys
the centrifugal force tends to tear the rim
asunder. This tendency is resisted by
the tenacity of the material of which
the wheel is composed. Since the cen-
trifugal force increases as the square of
the number of revolutions, it will be seen
that an apparently slight increase in the
number of revolutions per minute may
be sufficient to burst the wheel. For
solid cast-iron wheels and for built-up
wheels of cast iron where the strength
of the joint is equal to the strength of
the rim, the greatest number of revolu-
tions per minute that practice has indi-
cated to be safe may be found by the
following rule: Divide 1930 by the diam-
eter of the wheel in feet. Thus

where d equals the diameter of the wheel
in feet and N equals the number of
revolutions per minute. For example,
for a cast-iron flyw-heel 25 feet in diam-
eter, what would be the maximum num-
ber of revolutions allowable? Using the
rule just given, we have

X-

1930

= 77 rc-.olulions per minute.

September 26. 1911

POWER

477

Why Central Stations Catch
Isolated Plant Business

By Henry D. Jackson

That the central station has been able
in the past, and will he able in the future.
to get much of the isolated-plant busi-
ness, is not hard to understand if one
takes time to investigate. In the first
place, the sales agent of a central sta-
tion is a trained engineer. He knows
not only the cost of producing power in
his own plant, but also what the aver-
age manufacturing plant is paying for it;
his training and experience in gathering
information from the isolated plant en-
able him to place before the owner or
manager of the isolated plant, figures
showing what it costs them to produce
power, and unfortunately he is also able
to add unnecessary figures to these costs
which will make them very much higher
without fear of their being contradicted
in most cases. Owing to his presence.
his training and the lack of knowledge
on the part of the manufacturer, the cen-
tral-station agent can usually get a hear-
ing, and will frequently make such a
favorable impression that his figures are
swallowed whole.

On the other hand, the engineer of the
isolated plant is frequently looked upon
by the manufacturer as a necessary evil,
his sole duty being to keep the plant in
operation. He is not expected to make
a careful and accurate report of what
his boilers and engines are doing or what
the machinery requires in the way of
power; so long as he keeps the plant
moving he is considered to have done his
duty. This is an unfortunate condition.
No manufacturer would consider hiring a
man as the head of his department who
could not give him accurate figures re-
garding the cost of all material and labor
in his department, and, in general, the
entire manufacturing cost, that the manu-
facturer may know whether this depart-
ment is showing results.

The power plant is as important a part
of the business as any other, and the en-
gineer should be the manager of this de-
panment and be able to deliver to the
owner such a report as is delivered by
the head of any other department. He
should be trained to keep an accurate
record of everything entering the power
plant and its operations, these reports
' be in such form that the owner at any

•nc may determine what the cost of

■ wer might be from day to day, week to

ek. month to month, and year by year.

!!ierest, maintenance and depreciation

should be charged off against the plant,

and a careful record kept of everything

ruering into the cost of power.

To do this requires that the engineer
. t more than a mere engine-runner. It
requires that the plant be fitted with ap-
paratus necessary for weighing the coal,
measuring the water, keeping track of the
oil, waste, general supplies, repair parts.

etc. The engineer should be provided
with indicators and all that is necessary
to determine the amount of power re-
quired in various parts of the factory;
if the plant be equipped for electric
drive, recording wattmeters should be
installed. Report blanks .should be pro-
vided for the engineer, and daily reports
should be rendered to the clerical depart-
ment giving the condition of the boilers,
the number of boilers in service, the
amount of coal fired, the character of the
coal, the amount of water evaporated,
the labor costs and supplies used; in
short, the information which would en-
able the manufacturer at any time to
compare his power costs.

In many plants where apparatus is so
arranged that the engineers could keep
such records, the salaries are so low
that an engineer capable of keeping these
records will not accept the position. The
lesson is plain; men should be employed
who are capable, and they should be paid
enough to warrant their getting satisfac-
tory results. They should be paid in
proportion to the value of their ser\'ices.
as is any other department head. De-
mand records from them which are of
service, and rely upon these records.
When this is done the central-station
agent will have hard work to prove that
he can supply power at a price that is
comparable with a properly run isolated
plant.

As it is now, the central-station solicitor
can give cost figures for the operation of
the isolated plant that are manifestly
absurd to those who are trained in power-
generation matters, and the only recourse
isolated-plant owners have is to refer
such matters to a consulting engineer,
and rely upon his judgment. To depend
upon the central-station man for such
figures is unwise as he is unavoidably
prejudiced, and frequently worse than
that. The isolated-plant owner should
take the same ground here that he takes
in the purchase of any other of his sup-
plies. When he purchases goods for his
business, if the concern is large enough,
he employs a purchasing agent to see
that he gets what he pays for. Materials
are submitted to his department head,
who is a trained specialist, and he re-
ports as to whether the goods arc suited
to the purposes. As a rule, he knows
nothing about prices, as he is simply a
judge of the materials offered. This
report then goes to the purchasing agent,
who compares it with the cost of the ma-
terials and purchases those materials
which for the price will give the best
results.

The power plant should be handled in
exactly the same way. The study of a
number of power plants shows that this is
not done in very many cases, even in large
establishments. Coal is often purchased
at the lowest price, regardless of its heat-
unit value, and materials are usually
bought regardless of whether they will

properly serve their purpose. Coal should
be purchased on the heat-unit basis, or
on the basis of that coal which will
evaporate the largest amount of water
per unit of cost, and supplies should be
purchased on the basis of that price
which will result in the lowest cost.

Until some such method of handling
the power plant is devised, the power de-
partment will continue to be operated at
an excessive cost, and the central-station
agent will continue to have an excellent
opportunity for securing business which
otherwise would be unobtainable.

Oil in \\ yoniing

The United States Geological Survey
has just issued, as Bulletin 452, a report
on "The Lander and Salt Creek Oil
Fields, Wyoming." by E. G. Woodruff
and C. H. Wegemann.

Practically all the development in the
Lander field, says Mr. Woodruff, has
been confined to the southeastern dis-
trict, along Little Popo Agie river in
the vicinity of Dallas. The history of
this oilfield is far more interesting than
that of any other in Wyoming, for here
Bonneville discovered oil in 1833. From
the date of his visit to 1867 the oil
spring was unknown except to hunters
and trappers who frequented the locality
to procure the oil for medicinal purposes.
In 1883 and 1884 three oil wells were
drilled, all of which were productive,
but on account of keen competition from
the Eastern oil producers the first
Wyoming oil company had to abandon
its enterprise. For some time the wells
remained packed, but the oil that flowed
from the wells through leaks was utilized
to some extent by the ranchers for miles
around as a lubricant and by the gold
mines and fiour mills for steam making.
Recently operations at the wells have
been resumed on a more extensive scale.

The oil is adapted to several uses. It
forms an excellent fuel, comparing
favorably with the Texas or California
oils, and is now employed for that pur-
pose in practically all the development
work in the Little Popo Agie district.
Some of it can be used in its raw state
as a lubricant, though in general it is
not suitable for that purpose. As the
oil contains a heavy asphalt base, it is
good for oiling roads.

Perhaps one of the most interesting
wells in the Salt Creek oilfield is one
drilled in 1910 which struck oil under
pressure in shale at a depth of 1176
feet. This well yielded an unusually
large amount of oil for a shale well.
Oil travels much more slowly .hrough
shale than through sandstone, and where
large quantities are produced from shale
a slight crevice or fissure is generally
present. This fissure may be a fraction
of an inch in width and yet be of suffi-
cient extent to contain large quantities of
oil and to allow the oil to reach the
well rapidly.

P O W F R

September 26. 1911

Power Dc\cl()pnicnt on the
Los Angeles Aqueduct

By LeRoy \V. Allisotj

In connection with its aqueduct project,
Los Angeles, Cal., is afforded an excep-
tional opportunity for the development of
electrical power. This aqueduct under-
taking is a notable example of municipal
enterprise; Los Angeles, with a popula-
tion of a little over 300,000, shows im-
plicit confidence in its future by incurrinT;
a bonded debt for this work which wii!
ultimately total about 530,000,000.

A few features of the topography of
the aqueduct route, shown in Fig. 1. and
of its construction, will aid in understand-
ing a general description of the plans for
hydroelectric development. Owens river,
the source, about 240 miles from Los
Angeles, is fed from the mountains of the
Sierra Nevada range, which form the
eastern boundary of the Yosemite Nation-
al Park. It flows southerly through the
valley formed by these mountains and
the White and Coso ranges, emptying into
Owens lake, in Inyo county, about 100
miles from its rise. This lake covers an
area of about 175 square miles and has
no surface outlet. Except for a distance
of approximately 60 miles of mountain-
ous territory, the route of the aqueduct
lays through the Mojave desert, offering
many difficulties to construction work of
this character. For the first 20 miles,
the aqueduct is a canal about 50 feet wide
and 10 feet deep; then it is in the form
of covered and uncovered conduit, tun-
nels through mountain rock and steel si-
phons, as the natural conditions require.

Mountain water, at the rate of 260
million gallons net per 24 hours, will be
delivered to the city by means of reser-
voirs situated in the San Fernando val-
ley, about 20 miles distant. Including
reservoirs to be placed along the route
for the conservation of the supply, the ca-
pacity of this impounding system will be
about 370 million gallons. The elevation
at the aqueduct intake is 3812 feet, at
the reservoirs in the San Fernando valley
about 1165 feet, while the average in Los
Angeles city is close to 300 feet. Hence,
the system throughout will be one of
gravity flow, eliminating any expense for
pumping machinery and affording greater
simplicity of operation as well as reduced
maintenance cost. It is expected that the
aqueduct will be in service by December,
1912.

Development

The feasibility of developing electric
power in conjunction with the aqueduct
was reported upon by a consulting board

Di\^t5ion Creek

Power House,

600 Kw.

/ San Froncistjuito
PowerHouse No.l, 51,750 Kw.

''^ San Francisquifo
' - Power house No. 2.
32,000 Kw.

. ^ Fernando Power House
^ ^,^and Switching Sfatton,
XT 7250 Kw.

Los e^-A'?? Los A ngeles Sub Stn.

Angeles =g* Total Capacity

a 90.000 Kw. • ■'•

90.000 Kw.

Fig. 1. Route of Aqueduct and Trans-
mission Line

of three experts, Prof. W. F. Durand and
Prof. H. J. Ryan, both of Leland Stanford
University, and O. H. Ensign, of the
U. S. Reclamation Service.

The available head of water above San
Fernando valley is 3812 less 1165, or an
approximate total of 2647 feet; this is es-
timated to afford a total generating ca-
pacity of 48,000 kilowatts. The location
of power plants, switching stations and
transmissions lines along the aqueduct is
shown in the accompanying diagram. Fig.
1. Division Creek power house of 600
kilowatts capacity and Cottonwood plant
No. I of 1500 kilowatts have been com-
pleted and put into commission, taking
water from two of the mountain streams
near the aqueduct intake. Transmission
lines have been strung for a distance of
about 150 miles, making power available
for construction purposes and for lighting
the town of Independence, in Inyo county.
Cottonwood power house No. 2, of 2500
kilowatts capacity, is now being built,
and the four other stations will be con-
structed as rapidly as possible, making
a total of seven generating plants, with
the respective rated capacities noted on
the diagram. The ratings are based on
an average aqueduct flow of about 400
cubic feet per second, a flow at the Divi-
sion Creek plant of 8 cubic feet per sec-
ond, and a rate at the Cottonwood sites
of 20 cubic feet per second.

In the San Francisquito canon, about
40 miles from Los Angeles, one of the
finest points in the course is offered for
power development by a "step" in the
aqueduct grade of 1500 feet. At this site
the two largest plants will be erected.
They will be provided with storage reser-
voir facilities for impounding, so that
power can be generated as needed. This
power will be available in two large
blocks, of about three-fourths of the ca-
pacity output, giving a maximum peak de-
livery at the Los -Angeles substation of
approximately 90,000 kilowatts. The res-
ervoirs will serve to prevent interruption
of service through any failure in the
aqueduct north of the canon, and are also
expected to eliminate the usual draw-
backs to hydroelectric development, such
as irregularity of stream flow due to an-
nual low-water period, the effect of sea-
sonal changes, etc., thereby making aux-
iliary steam equipment unnecessary. An-
other excellent feature is the proximity
of the main plants to the central distribut-
ing station in the city, a distance of only
40 miles; this will permit of ready repairs
and improvements to the generating
plants.

Steel pipe and concrete tunnels will be
used for such sections of the line as are
under pressure, fully protected by safety

September 26. 191 i

POWER

479

relief valves and regulating devices to
prevent rupture from shock.

The transmission lines will be carried
on steel towers, and the first 40 miles, be-
tween Division Creek and Cottonwood,
will be operated at 30.000 volts; for the
-emaining 185 miles, the potential will be
increased to 80,000 volts.

The initial cost of this development is
unusually low, being from S60 to S80 per
kilowatt, delivered at the city station.
From tables compiled by the Ontario Hy-
droelectric Power Company, such devel-
opments range from S67 to over S200
per kilowatt.

Utilization of the Power

It is natural that the three large power
companies now established in Los An-
tieles and vicinity do not regard this mu-
nicipal enterprise with particular favor.
These organizations have invested many
millions in properties; they employ a

rge number of residents, and they pay

ose to SIOOO a day in city and county
:jxes.

Inclusive of power for all purposes, the
nverage city peak load may be estimated
:;t ,^(1,000 kilowatts, a 24-hour period giv-
ing; an average load curve about as shown
in Fig 2. Including neighboring com-
munities, the peak demand is approxi-
mately 58,000 kilowatts.

One of the most important problems
confronting the consolidation commission
of the city, a board organized to consider
the water and power question, was the
distribution of the power to be available.
Some of the city officials were in favor
of disposing of the power to private com-
panies in blocks for a certain term of
years at a price offering a fair rate of
profit on the investment, with an equit-
able charge to consumers. This would
save the city the expense of a distribu-
tion system and afford a period in which
to replenish its resources.

Accordingly the power companies were
invited to present a proposal to be placed

about 15 years, to pay the city S35 per
kilowatt-year at the switchboard, if the
rate to the consumers remained as now,
7 cents; or S30 if the consumers' rate
became 6 cents, or S25, if 5 cents. The
highest rate would net the city S480,-
000 a year, but E. F. Scattergood,
chief engineer of the city power bureau,
replied that the city could make a net
annual profit of S700,000 by charging the
same rate (7 cents), using but one-sixth
of the total power generated; an excess
of S220,000 more than offered, and leav-
ing five-sixths of the power still to be
sold.

At the election in March. 1911, a so
called "straw vote" was taken on the two
propositions: (1) Shall the city dis-
tribute directly to its inhabitants the elec-
tricity to be generated by it on the Los
.Angeles aqueduct, or (2) shall the city
sell to the lighting companies for a term
of years the electricity to be so gener-
ated. The former proposition was car-
ried by a vote of ten to one.

It is estimated that a distributing sys-
tem capable of reaching all consumers
within the present city limits, an area of
100 square miles, and serving the street
lighting (now costing the city S2 1,000 a
month), can be installed for about S4,-
500,000, exclusive of any railway service,
which is governed by private interests.

As provided for in recent city-charter
amendments, a Power and Light Bureau
will be organized, having under its juris-
diction all features of the work, including
city distribution. E. F. Scattergood, chief
electrical engineer of the aqueduct and
head of the present power bureau, will
be in charge.

A Novel Commutator
Lubricant

By L. M. Johnson

Having had a great deal of trouble and
annoyance with direct-current commu-
tators and brushes becoming dry and

40P00

yumuiuij

EBffl

ilj|ii|uniiiiaBBg

Fic. 2.

A.M. Noon P.M.

An Average Load Curve for Lo-; Angeles

before the people at a coming election, a
two-thirds vote being necessary for the
ratification of any such sale. The power
companies, however, claiming insufficient
time to make an intelligent estimate,
failed to submit a positive proposition. A
tentative proposal was sugeestcd at one
of the conferences, based on a lease of

scratching, I cvperimcntcd with numerous
methods of lubricating the brushes, but
with very little success. One day, when
I happened to have in my hand a piece
of flax rod packing, I stopped to look at
a large motor that was making a great
deal of noise from the brushes scratch-
ing; remembering that flax packing con-

tains a large amount of oil, it occurred
to me to tr>' rubbing the packing against
the commutator. Upon doing so I was
surprised to note that the commutator
at once brightened up and that the
brushes stopped scratching. I then cut a
piece of square flax packing the length
of the commutator face and laid it on
the commutator in front of the brushes

A NfAl L COM.MI'TATOR LUBRICANT

so that the rotation of the commutatoi
would crowd the packing against the
brush holders, as shown in the accom-
panying picture.

After a day's run the packing was
taken off for examination, and it was
found that the side next to the com-
mutator was quite smooth and coated
with fine copper dust and dirt that it had
collected from the commutator. This
treatment was then applied to other
motors and generators, and after a trial
over a number of months it has proved
very satisfactory both in keeping the
commutator clean and making the brushes
run quiet. The commutators of two
heavy-duty motors, which it was formerly
necessary to sandpaper every morning,
do not now have to be sandpapered
oftcner than about once a week.

The packing should bear on the com-
miitator heavily enough to collect all
dust and dirt and it should be turned
over every day or so until all four sides
have been used; then a new piece should
be put on.

Several power-supply undertakings are
now operating successfully at 110,000
volts, and a few l40.(X10.vnlt lines are
projected. A voltage of 200,000 is con-
sidered to be within the region of prac-
ticability; in fact, it is now regarded at
much more practicable than was one ol
100,000 volts a decade ago.

480

POWER

September 26. 191!

The Reniinijjtoii Kerosene
Engine

A very simple form of internal-combus-
tion engine intended to burn kerosene
has been brought out by The Remington
Oil Engine Company. Stamford. Conn.,
and is illustrated by the accompanying
engravings.

The engine is of the automatic-igni-
tion type — that is, the charge is ignited
without the use of auxiliary devices —

Fig. 1. Sectional Vie* of Remington
Engine, Also Showing Ports

and operates on the two-stroke cycle.
Ignition of the fuel is caused by a nickel-
steel rod C, which is located in a circular
pocket in the cylinder head and retains
sufficient heat from each combustion to
enable the heat in the air compressed on
the succeeding upstroke to raise its tem-
perature above the igniting point of the
fuel. The cylinder head is hooded to
conserve the heat developed in the com-
bustion chamber and also to provide a
sort of heater for starting.

The control of the air and products of
combustion is effected by means of ports
in the cylinder wall which are covered
and uncovered by the piston, as is com-
mon with practically all small engines
working on the two-stroke cycle. With
the piston at the bottom of its stroke,

as shown in Fig. 1. the exhaust port A
and the inlet port on the opposite side
of the cylinder are uncovered and air
which has been compressed in the crank
case rushes through the transfer pass-
age and inlet port into the cylinder, ex-
pediting the exit of burned gases through
the exhaust port A. When the piston is
pushed up by the momentum of the fly-
wheel, the air in the cylinder is com-
pressed to about 125 pounds, gage, and
thereby heated, of course. The heat of
compression restores the temperature of
the ignition rod C, which has been low-
ered during the expansion stroke, and as
the piston reaches the upper end of the
compression stroke, a small pump de-
livers a spray of kerosene through the
nozzle shown in Fig. 2 against the end
of the ignition rod. The charge is there-
by ignited, combustion being supported
by the air previously compressed in the
cylinder, and the hot gases expand and
force the piston down, in the well known
manner. At the end of the downstroke
the exhaust and inlet ports are uncovered,
releasing the burned gases and admitting
air from the crank case again, starting
another cycle.

When the piston travels upward, a
partial vacuum is formed in the crank
case, which is entirely closed in as soon
as the piston covers the port at the end
of the transfer passage. When the pis-
ton reaches the end of the upstroke it
uncovers the port shown beneath the ex-
haust port A. This third port admits air
to the crank case, the atmospheric pres-
sure forcing the air in to "fill up" the
vacuum there. When the piston descends
again, the air just admitted to the crank
case is compressed to about 5 pounds
above atmospheric, so that when the
inlet port is uncovered by the piston the
pressure in the crank case drives air into
the cylinder.

The quantity of air taken into the cyl-
inder is the same for every stroke, no
matter what the load may be. The quan-
tity of fuel oil delivered to the spray
nozzle is varied by a centrifugal gov-

ernor which controls the stroke of the
kerosene pump. The governor consists
of an L-shaped weight £, Fig. 2, pivoted
to an arm of the flywheel at P and pro-
vided with an extension finger at its free
end; this finger shifts a cam G along the
shaft. This cam actuates the pump
plunger and the stroke of the plunger
depends on the position of the cam along
the main shaft; when the cam is moved
inward, toward the crank case, the pump
stroke is shortened, thereby reducing the
quantity of kerosene delivered to the
spray nozzle. Centrifugal force in the
governor weight tends to move the cam
inward and a helical spring opposes this
effort.

The long lever /, pivoted to the bracket
H. is used to control the maximum speed
of the engine by hand and to shut it
down. The lower end of the lever en-
gages the cam G and determines the
point to which the governor spring can
pull the cam outward, and thereby the
maximum possible travel of the kerosene-
pump plunger. When the handle of the
lever / is pulled out as far as it will go,
the pump is put out of action and the

Fig. 2. Sectional View of Re.mington
Engine. Also Showing Governor

.Mechanis.m

fuel supply is therefore cut off. stop-
ping the engine. This is necessar>- be-
cause the ignition is automatic and can-
not be shut off.

To Stan the engine, the hollow hood
on the cylinder head is heated by a kero-
sene torch furnished with the engine.
When it is hot, a single charge of oil

September 26, 191 1

POWER

481

is injected into the cylinder by working
the hand lever connected with the pump;
the flywheel is then pulled smartly back-
ward, thereby compressing the charge,
which ignites before the piston reaches
the highest point, and starts the engine
in the forward direction.

Preventing Boiler Corrosion
in Bituminou,s Gas Pro-
ducer Plants
By C. B. Geoffrey

In operating a bituminous coal-gas
producer of the down-draft type a great
deal of trouble is experienced in most
cases through deterioration of the waste-
heat boiler.

In an equipment under the writer's
supervision the boiler trouble was so
serious that it was about decided to tear

ranged to take care of both generating
sets.

For starting a new fire, a steam ejector
was provided, as shown, above the top
tube sheet of the boiler, which drew the
gas through the latter while starting up.
Before cutting in on the line this ejector
was closed off and the main gas valve
opened into the scrubber.

A new set of tubes had just been in-
stalled and the usual test indicated no
leaks. The fires were started as usual,
but before cutting in on the line the man-
hole cover was removed from the top of
the gas space above the tube sheet and
every^thing was found to be thoroughly
wet; water completely covered the top
tube sheet to the hight of the beading
on the tube ends and was running down
the tubes. The strong smell of am-
monia and knowledge of the perfect job
of retubing which had just been tested

i^inal Iccation of tjc. ■

Arrangement of Generators and Boilkh

out the water space, line up the shell
and supply steam for water-gas runs and
the exhauster engine from a hand-fired
boiler, at considerable expense for boiler
equipment, added labor and continuous
loss from nonrecovery of the sensible
heat of the gas.

The arrangement of the apparatus con-

•■■d of duplicate generating sets, each

uding two generators and a wastc-

hcat boiler, arranged as shown in the

accompanying sketch; only one set of

scrubbers and one c\hausicr were ar-

indicatcd that the water or liquid had
been precipitated from the gases of com-
bustion being rapidly cooled in contact
with the cold boiler tubes; and as the
velocity of the gases was considerably
reduced In the large space above the
tubes they had been apparently creating
an artificial rainsiorn. It was further ob-
scr\'ed upon opening the cleaning door
at the bottom that an inch or so of this
fluid had collected in the bottom space.

I endeavored to remedy this condition
by fllline the boiler with hot water

through an injector before starting the
fire, and this improved conditions to
some extent. The chief improvement,
however, was accomplished by removing
the ejector from the scrubber end of
the boiler and applying h on the bottom
gas connection between the generators.
Afterward, upon starting new fires the
gases were not passed through the boiler
until the fire beds w^ere at their normal
high temperatures; under these condi-
tions and by treating the boiler to warm
water initially no further trouble was ex-
perienced than would have been with
an ordinar\- hand-fired boiler.

In cutting in a producer with this ar-
rangement it is particularly advisable to
open the purge valve for a moment be-
fore allowing gas to go to the holder, as
a considerable volume of air may be en-
trapped in the boiler space and piping
which should be blown out, especially
when a holder of small capacity is used.

Coal in California
California's production of coal in 1910
was 11,164 shon tons, with a spot value
of S18.336, according to E. W. Parker, of
the United States Geological Survey. In
1909, California showed the largest per-
centage of increase among the coal-pro-
ducing States, and in 1910 the largest
percentage of decrease.

From January to September of that
year the Stone Canon mines had produced
75 per cent, of the State's output for the
entire year. No coal was produced at
this mine in 1910 and the production de-
creased about 75 per cent. All of the
lignite coal produced in 1910 came from
Amador and Riverside counties, princi-
pally from the lone mine in Amador
county. The Stone Cation coal is a non-
coking bituminous coal of good quality
and should make an excellent domestic
fuel. It stands exposure well and with
favorable freight rates would compete
successfully with foreign coals in the
markets of San Francisco and other cities
of the State.

LRTTER

Ca.solene in the Lubricating
Oil

A 30.horsepower two-cylinder marine
engrne working on the two-stroke cycle
gave trouble very soon after its installa-
tion, the trouble being that the wrist
brasses became hot and cut very rapidly.
It was discovered that the heating was
caused by gasolene in an unvaporized
state getting into the crank case and
washing the bearings clean of nil.

Steam-engine cylinder oil was tried as
a last resort and it proved very cITective;
just enough gasolene got into the case to
thin the oil to about the right degree for
lubrication.

Llovi) V. Beets.

Nashville. Tcnn

482

POWER

September 26, 1911

Kerosene Oil ;i l-'rotection to
Pipes and Pumps

Those having charge of pumps in and
around mines will find that if they place
a kerosene drip on the suction pipe they
will have no more trouble with the pipe
corroding and will also save the pump
from the grit and sulphur water. Tap
the suction pipe close to the sump for a
■4-irich pipe and valve. Then bush it
up to 2y2 inches and place a piece of
2'j-inch pipe 2 feet long on it, or a pipe
according to the size of the suction. I
use 1 gallon every 10 hours for a 6-inch
suction pipe. I find that in using kero-
sene I can prolong the life of the pumps
and pipe about three times as long as
when no oil is used.

L. B. Scott.

Clarksburg, W. Va.

Erecting a Steel Stack

The stack to be erected was 127 feet
high, 66 inches in diameter and was
built to supply draft to two 300-horse-
power water-tube boilers. It could not
be hoisted into place without being cut
up into sections because the boiler house
was completed and hemmed in on three
sides by three buildings and on the other
side by a mass of telephone and tele-
graph wires, and three lines of railroad.

The stack was shipped in three 30-foot
and one 15-foot breeching sections. The
first thing done was to place the breech-
ing over the boilers; this was a compara-
tively easy matter. The first section was
then cut into 5-foot lengths and sent up
one at a time by block, tackle and a gin
pole, without very much trouble. The
limit of the gin pole was then reached
and other means had to be provided.

It was decided to cut the other two 30-
foot sections into 5-foot lengths and then
cut those in half to enable the work to
be carried on around the pole and tackle.

Starting inside the breeching, a scaf-
fold was built; a length of 2x4-inch tim-
ber was placed vertically in the center of
the stack and crosspieces of the same
dimensions were cut to make a snug fit
against the side of the stack. These were
then spiked to the vertical timbers and
made a very strong scaffold. Cleats were
then nailed to the vertical timber to aid
the workmen in going up and down the
stack.

A 12-foot section of 2' '-inch pipe was
then bolted to the upper section of the
stack by means of 3'/.-inch bolts, three
rivets having been left out for the pur-
pose. An eyebolt was placed at the

upper end of the pipe, to which was fast-
ened the block and tackle.

A half section of the stack was then
hoisted and bolted temporarily in place
until the next section was hoisted, when
they were riveted together. The pole
was then raised to the section just
erected and the same operation repeated,
the scaffold, of course, being added to
as the sections went up.

The riveter's stage was made of !!_■-
inch angle iron and lx6-inch oak boards,
the top of the stage being supplied with
a grooved wheel which enabled the
riveter to swing around the stack.

One would think that this was a slow
method of erecting a stack, but the whole
operation took only seven working days,
including the riveting, and half the time
the men were nearly suffocated by the
smoke coming from the other stacks at
the same plant.

F. W. Fischer.

Knoxville, Tenn.

Combination Turbine Gen-
erator and Pump Unit

There has been installed recently by
the West Boylston Manufacturing Com-
pany in its cotton mill at Easthampton,

Flexible couplings are employed be-
tween the two machines so that it is
possible to cut out the pump and run
the generator alone. The tandem ar-
rangement is employed as there is no
occasion to run the pump without the
generator.

The pump circulates the hot water of
the mill-heating system; the generator
furnishes excitation for the main gen-
erators which provide the power for
the mill motors during the. day. At
night the generator is switched onto the
lighting circuit of the mill and thus the
turbine carries a 24-hour load at prac-
tically all seasons of the year.

During the winter it is necessary to
run both the generator and pump at all
times; but in the summer months the
pump is disconnected and the generator
is operated alone. This set runs at 2500
revolutions per minute and the turbine
is operated noncondensing, the exhaust
being used in the summer for heating
the boiler feed water and in the winter
for heating the water of the hot-water
heating system.

W. H. WlLLH.MS.

Easthampton, Mass.

Sampling and Analyzing
Coal

As the purchase of coal on a B.t.u.
basis seems to be coming more general
every day, perhaps a description of the
system employed in a plant burning from
000 to 1000 tons of coal a day may be
of interest.

The coal is received at the dock in
barges and is hoisted to the top of the

Elevation of Turbine, Generator and Pump Unit

Mass., a combination pumping and elec-
tric-generating set which embodies some
unusual features. The unit consists of
a 75-horsepower steam turbine directly
connected to a 30-kilowatt direct-current
generator and an 8-inch double-suction
pump. The generator is situated next to
the turbine with the pump connected
bevond.

coal tower where it is run through a
crusher and is broken up into lumps of
uniform size. From the crusher it passes
to two weighing hoppers where the sam-
ple for analysis is taken. Each weigh-
ing hopper has an automatic sampling
device that takes about a 6- or 7-pound
sample from each hopperful and deposits
it in a can reserved for that purpose.

September 26, 191 1

POWER

483

When the boat is light and the last ton
has been weighed out, the samples from
both hoppers are spread on the floor
and thoroughly mixed in one pile, this
being quartered down until about 20
pounds of the original sample remains,
which is the official sample of coal, no
other being recognized.

The sample is then broken up into
lumps of about '4 inch in size and
quartered once more. Part of the sample
is put in an air-tight glass jar and is
used in making the moisture determina-
tion; the remainder is run through a mill
and ground up as fine as possible, put
in a canvas bag, labeled with the neces-
sary information pertaining to the boat
from which it was taken, etc., and sent
to the laboratory for analysis together
with the moisture sample.

Upon reaching the laboratorj' the fine
sample is again quartered and then passed
twice through a 60-mesh sieve. A portion
of it is placed in a small glass tube for
■ analysis and the remainder is kept for a
reserve sample or for a check analysis
in case one is needed. The system of
analysis employed is the one recom-
mended by the American Society of
Chemical Engineers, a brief description
of which follows:

About 100 grams of the coarse mois-
ture sample is weighed out into a glass
crystallizing dish and then subjected to
a temperature of about 110 degrees Fah-
renheit for three hours in the drying
oven. It is then reweighed and the per-
centage of moisture calculated from the
loss in weight. This moisture determina-
tion is very necessar>' as oftentimes the
bill of lading and the coal-tower weights
do not agree. The allowable moisture is
4 per cent.; anything over this amount is
deducted from the contract weight.

To get comparative results a fine mois-
. ture determination is also run; approxi-
mately one gram of the fine sample is
weighed out and then placed in the dry-
ing oven for one hour, when it is re-
weighed and the moisture in the sample
thus determined.

Another gram of the sample is weighed
out and placed in a platinum crucible
for the proximate analysis — the deter-
mination of the fixed carbon, volatile
matter and ash. The volatile gases are
first driven off by placing the covered
crucible over a bunsen burner for seven
mtflufes, when the sample is reweighed.
The sample is then placed uncovered over
a burner and burned down to ash. Then
100 per cent, minus the sum of the per-
centages of volatile matter, ash and mois-
ture gives the percentage of fixed car-
bon.

The B.t.u. determination is made in an
Atwatcr bomb type of calorimeter and
the percentage of sulphur is found by
titrating and filtering the washings of the
calorimeter.

The chemical analysis is practically
positive, but there is always a question

as to the method of sampling and any
new ideas from the readers of Power
will be welcomed.

Ho^s•ARD Barr.
New Rochelle. N. Y.

Retubed the Condenser

In a chemical works a condenser was
used to cool a certain vapor from 600
degrees Fahrenheit to a liquid state at
approximately 20 degrees Fahrenheit. The
vapor came intermittently, so that the
condenser had time to cool down to the
temperature of the refrigerating bath
passing through the tubes. After being
subjected to five or six successive heat-
ings and coolings every day for a week,
the condenser leaked at every tube end
and a mixture of condensed vapor and
refrigerating liquid was the result. Re-
expanding the joints was not productive
of lasting benefit.

It was out of the question to get a
suitable condensing apparatus inside of
three months, because of the isolated lo-
cation of the plant, and as there was
plenty of tubing on hand the condenser
was fixed as shown in the sketch. By
leaving a few tubes out here and there
and plugging the holes, double-bent tubes
were used, the bends being introduced
to take care of the expansion. The tubes
were expanded tightly and when, four
months later, apparatus designed for
the work was received, the condenser
was still tight.

Similar cases do not present them-
selves very often, but when a surface
condenser leaks at the tubes it is gen-
erally very difficult to maintain a proper
vacuum. If the condensing water is used

Water Tank. Signal System

I had the problem of a tank signal to
solve some months ago and the results
may be of interest.

The chief feature lies in the use of a
heavier than water body to operate the
contacts instead of the usual float.

A galvanized-iron rod, or a galvanized-
iron pipe of a length about equal to
the depth of the water, is sus-
pended in the tank, either from a
helical spring, as shown at A, or from a
counterbalanced lever, as shown at B.

( "^ 1

Water-tank Signal Syste.ms

The upper end of the spring, or the
lever, is placed at such a hight that
when the tank is empty the suspended
rod or pipe will just clear the tank bot-
tom.

On filling the tank the rod will rise,
allowing the spring to close or lowering
the counterbalance weight an amount
depending on the weight of the rod and
the stiffness of the spring or the ar-
rangement of the counterbalancing ap-
paratus. This rising of the operating
rod is because the rod is lighter when

How TMH Tl'BFS WpKL BiNT

in the boilers it may carry alftng some
cylinder oil to the boilers with the usual
results.

Therefore some scheme similar to the
above should be adopted to keep the
lubes tight. The condenser may be some-
what larger, but it will prevent some un-
anticipated troubles.

P. P. Fenaun.

Lynn, Mass.

immersed in water. A little experiment-
ing will enable one to arrive at the
strength of spring or form of lever re-
quired.

The spring application of the foregoing
principle is viriuallv frictionless; the
lever device introduces only the friction
of a single roller bearing. Either of
these devices will therefore operate sig-
nals capable of the most minute ad-

484

POWER

September 20, 1911

justment, a feature hardly obtainable in
any of the usual devices, which ordi-
narily move by more or less irregular
jerks.

The electrical end of this interesting
problem has been already well discussed
in other articles, and needs no further
comment. The mechanical advantages
of this apparatus, as well as its cheap-
ness, are obvious.

George A. Main.

Daytona, Fla.

Cost of Steam to the Con-
tractor

I was recently asked to estimate the
cost of steam supplied to a contractor
for operating a hoisting outfit, which con-
sisted of a 7xl0-inch duplex hoisting en-
gine and a steam turbine for swinging
the boom.

Steam from the boilers at a pressure
of 125 pounds gage was supplied through
200 feet of 2-inch pipe to the engine
and turbine, which exhausted to the at-
mosphere. The capacity of each bucket
was one cubic yard and its weight 700
pounds; the hook and pulley weighed 200
pounds. As 1 cubic yard of gravel weighed
2800 pounds the total weight lifted each
time was 3700 pounds. The average
hight the buckets were lifted each time
was 40 feet. A record of several days
showed that the average number of buck-
ets lifted daily was 100, or 10 buckets
hourly. The work done per hour was
therefore 1,480,000 foot-pounds, or prac-
tically -kl horsepower.

Allowing 33'} per cent, for friction of
the pulleys, cable and engine, the power
developed by the engine for hoisting the
loaded buckets averaged one indicated
horsepower per hour, and another indi-
cated horsepower for operating the boom.
As the amount of steam for this engine
and turbine is about 50 pounds per indi-
cated horsepower per hour, the consump-
tion of steam for power purposes was
100 pounds per hour.

The heat loss per square foot per ho.ur
per degree of difference between the in-
side and outside temperatures of the pipe
is 3 B.t.u. As the temperature of steam
at 125 pounds gage pressure is 353 de-
grees Fahrenheit and the estimated out-
side temperature drop during the work
would be 63 degrees Fahrenheit, there
would be a difference of 290 degrees Fah-
renheit.

The radiating surface of 200 feet of
2-inch pipe, including a few feet of 1-
inch pipe, is approximately 130 square
feet, and the heat loss per hour was esti-
mated as 113,100 B.t.u.

The latent heat in one pound of steam
at 125 pounds is 868 B.t.u.; therefore, the
condensation of steam was 130 pounds
per hour. As Kent's rate of condensa-
tion in an 8-inch bare steam pipe for 130
square feet of radiating surface with
an average temperature difference of 272

degrees Fahrenheit is 110 pounds of
steam per hour, it would appear that,
with proper allowance for a greater tem-
perature difference and smaller pipe, 130
pounds per hour is conservative. An
allowance of 20 pounds must be made
for leakage in the pipe line. This con-
densation and leakage loss was therefore
150 pounds per hour, or 1650 pounds for
the 11 hours per day. The steam for
power purposes being 1000 pounds per
day, the total steam used by the con-
tractor was approximately 2650 pounds
per day.

The total boiler-house expense aver-
aged SHiSO per month and the amount of
steam furnished the mill is 3,575,000
pounds per month; therefore, I figured
that a rate of 0.46 per 1000 pounds
would be about right. For 2650 pounds
of steam per day the cost would be $1.22.

Twenty per cent, is a conservative fig-
ure to add to this cost to allow for in-
terest, depreciation and covenience of the
steam plant, making the total cost of
steam per day supplied to the contractor
SI. 46 or, in round numbers, SI. 50.

L. L. LOO.MER.

Waterbury, Conn.

Boiler Feed Pump Regulator

The accompanying illustration shows a
device for regulating the water level in
a boiler, the power-feed pump of which
is automatically controlled by a series of
electromagnets which increase or de-
crease the speed of the motor driving the
pump.

A sectional view of the casing is shown
at A. The phosphor-bronze corrugated
diaphragm B is connected by means of
a flexible joint to a brass stem passing
through a long stuffing box. It is con-

ment can be made through the lengthen-
ing or shortening of the stem by means
of a long thread and a lock nut. Steam
and water connections are made in the
same way for a regulator of the piston
type.

C. A. Mayer.
Hoboken, N. J.

Emergency Check Valve

Repair

Some time ago a 2; j -inch check valve

failed on a feed line leading to a boiler.

The boiler was temporarily cut out and

the bonnet of the check valve removed,

Ho'x THE Valve W.as Repaired

when it was found that the valve seat
had worked out of place, the threads hav-
ing all been worn smooth.

How to repair this valve while in place
was a puzzle, but finally the scheme of
holding the seat in place by the bonnet
was suggested. After taking several
measurements, a short section of 3'4-inch
boiler tube answered the purpose. The

;3333U^S^o/7

"Rr3333^5to«

Feed-pump Regulator

nected at the upper end to the rod con-
trolling the magnets.

The distance from the fulcrum to the
center of the stem is small compared to
the length of the arm; thus a very slight
displacement of the diaphragm will give
several inches of upward or downward
movement at the panel. The brass blocks
are movable and can be easily adjusted
to the proper position. A closer adjust-

section of tube was made with three
openings in its sides, as shown at A.
When placed in position in the check
valve, it came between the bonnet and
the seat, holding the latter in position
with the disk working inside the tube sec-
tion, the water passing through the three
openings on its way to the boiler.

Charles E. Nigh.
Morgantown. W. Va.

September 26. 1911

P O W b R

485

Babcock 6c Wilcox Headers,
Tubes and Baffle Walls

In the issue of July 18 appears an
article on page 105 entitled "Babcock &
Wilcox Headers, Tubes and Baffle Walls,"
by R. E. Pairman, who asks for the opin-
ion of Power readers. It so happens
that I have had charge of Babcock &
Wilcox marine boilers, 18 tubes wide and
12 high, fitted with single headers; that
is, each one holds the ends of 12 tubes
4 inches in diameter. These headers are
made of a very high grade of steel. Two
or three small cracks have shown on dif-
ferent occasions near the edge of a
handhole, but were very small, and had
been caused by severe "setting up" on
the plates and afterward the use of a
hammer and piece of steel bar to calk
around the edges of the plates that
did not seat well. This operation had
been a regular thing after cleaning the
tubes, and was practised even while pres-
sure was on the boiler, varying from 200
to 240 pounds, by a former chief engi-
neer.

Of course, I stopped this practice and
such few slight leaks as developed were
temporarily stopped by peening lightly
over the crack. Later these were welded
with the electric process and they gave
no further sign of trouble.

Tubes which bow have been remedied
by regulating the draft to prevent cold
air from entering the furnace. Lack of
water or of proper circulation and the
consequent overheating sometimes cause
bowing of tubes. Flaring the nipples
is a good plan but not necessary with
tubes. With horizontal baffles I have
experienced no trouble whatever.

J. A. McVay.

San Francisco. Cal.

Co,st of Furnace L pkeep

The article by Mr. Howard in the
August 15 issue, concerning the "Cost of
Furnace Upkeep," is quite complete.

We make it a business never to renew
a side wall or furnace lining until at
least 4 inches or one course of firebrick
has been either burned or broken out.
If small holes are burned or broken
out of the linings, pulverize old
pieces of firebrick, and mix them with
a shale mortar into what bricklayers call
ganister, a very thick mortar, and with
this thoroughly pack up all holes. It is
surprising how this will glaze over and
add to the durability of the wall. Shale
mortar, if a little salt is added, is equally

as good as a great deal of the fireclay
on the market and less expensive. The
shale, of course, should be thoroughly
pulverized before being wet and then
mixed to the consistency of a thin batter
or grout when used in laying up fire-
brick.

Blowoff pipes must be protected from
the fire, especially where cast-iron el-
bows are used. This can be very ef-
fectively and economically done by build-
ing a single-course firebrick wall on three
sides of the pipe, leaving the side next to
the rear end open for the inspection of
the pipe. A pier should be built from
the bottom of the combustion chamber
up to the elbow and then the wall should
be carried up tight against the bottom of
the boiler.

Where cast-iron or other rear-end
doors prove troublesome from warping
and letting in air, we find that to remove
these doors entirely, leaving the iron
frame in the wall and filling the space
with a single-course wall of ordinary
brick laid in shale mortar, is a stunt worth
trying. This wall can be kept plastered
in case cracks appear. It will last a
surprisingly long while and is very easily
removed in case any work is found nec-
essary on the rear end of the boiler, and
if the least bit of care is used the brick
can be used over and over again. For
convenience in cleaning the combustion
chamber and inspecting, we have an I8x
2-)-inch cast-iron door on either side of
the blowofT pipe. With this arrangement
it is easy to ascertain whether there is
any work required on the rear end with-
out bothering the wall of brick above.

In conclusion. I wish to say that the
do-it-now idea should not be overlooked
in keeping up furnaces.

Thomas M. Sterling.

Middlebranch, O.

Mr. Howard's letter in the August 15
issue on the above subject is interesting.

A few weeks ago wb had a discussion
on this same subject in Illinois Associa-
tion No. 28, National Association of Sta-
tionary Engineers. The consensus of

opinion was that it cost from 40 to 75
cents per boiler-horsepower per year to
maintain the furnaces and the brickwork
of the settings. These figures were the
averages covering several years.

It cost me for a 1950-horsepower plant
— Stirling boilers, extended-front Murphy
furnaces— S900, SI350, SI 120 and S1460
for four consecutive years. This makes
a total of S4830, or 62 cents per horse-
power per year, average. The plant con-
tained three 500- and two 225-horsepower
boilers. The cost of maintaining the
brickwork proper amounted to 80 per
cent, of the total expense. The figures
quoted cover only the work done by regu-
lar masons and do not include such work
as was done by firemen and water tenders
in making repairs of small breaks.

Some of the members claimed to be
able to maintain boiler settings for SS'/;
cents per horsepower per year and one
man said that it cost him almost SI.
Of course, these figures are affected by
the nature of the plant, the kind of work
it is doing, the nature of the fuel, etc.
C. W. Naylor.

Chicago, 111.

Need of Well Informed
Engineers

Considerable space has been devoted
of late in the columns of Power to arti-
cles dealing with isolated-plant manage-
ment and the inroads that have been and
are being made on it by the central sta-
tion.

Various suggestions have been made
for the keeping of suitable records and
data, which can be readily referred to if
needed; the cost of production per kilo-
watt has been dealt with at some length,
as has the importance of selecting the
right kind of supplies.

The machinery in a plant may be the
finest, but there are very few plant own-
ers who stop long enough to consider
that their fine machinery ought to have
the best men to care for it. In nine cases
out of ten, low-priced labor is hired and
in the course of time things begin to
happen and everything in the plant
stands badly in need of repair. The con-
sequence is that rather than spend the
amount of money required to place the
plant in working order central-station ser-
vice is installed, and. although the owner
is not aware of it, he is annually paying
out about three times as much as it
would cost him to put his plant in shape
and run it, because he is compelled to
pay more for his current than if he made
it himself.

486

POWER

September 26, 1911

The reason that so few engineers are
able to compute the cost of production
is not so much their lack of knowledge as
their lack of information along such
lines, as the cost of the original
outfit, the cost of insurance, taxes, de-
preciation, interest on the investment and
a few other things which are included in
the costs of running a plant.

Why do not the owners of plants realize
that the engineer ought to have this in-
formation and present it to him? Then
the engineer could prepare himself for
his fight with the central-station intruder
and wallop him so hard when he puts in
an appearance that he will gladly walk
on the other side of the street whenever
he has occasion to pass that way.

H. H. BURLEY.

Brooklyn. N. Y.

Emergency and the Man

The article on "Emergency and the
Man" in a recent issue interested me
very much.

Mr. Leslie says he was "both severely
criticized and highly praised," but he does
not say what the critic would have done
under like circumstances. My strong im-
pression is that he could not tell just
what he would have done at the moment.
To say that one should do this or do
that when an emergency arises is no
argument, and yet how common it is to
hear and, for that matter, for oneself
to say, "I would do" this or that, when
viewing a case in cold blood. As a mat-
ter of fact, you or I would as likely do
just the opposite when confronting an
emergency.

Did you ever have a boiler tube blow
out with 125 pounds steam behind it, and
a heavy fire in the furnace, when you
chanced to be in the immediate vicinity?
If you have not, you may.

I am not saying but what you would
do the proper thing, but it will all depend
on the condition of your nervous system
at that moment.

The presiding officer, as Mr. Leslie
states, who changed the topic from "what
to do" to "what did you do?" in an
emergency showed wonderful good sense.
Some years ago the writer made a
business visit to a planing and molding
mill not a thousand miles from the Bronx,
and was surprised to find the workmen in
a state of confusion. Some were run-
ning one way and some another; others
were shutting down their machines and
joining the excited men about the place.
All I could learn was that there was
trouble in the boiler room, as they put
it.

Curiosity prompted me to ask for the
foreman and I was told that he was
dow-n in the boiler room. Hastening in
that direction I found a man coming up
the stairs much excited and I asked him
what the trouble was. He informed me
that the engineer had gone down town

and the fireman had reported that he
would have to shut down as the engine
was lifting off its foundation. I followed
him into the basement, where I found a
high-speed engine of perhaps 100 horse-
power literally suspended from a heavy
driving belt which ran vertically up to
the line shaft in the mill above.

I suggested that they tighten down all
the anchor nuts to start with. It was
stated that this had been done several
times, but the trouble soon returned.

It was manifest that the whole equip-
ment was unstable and could not carry
its load except with a heavy tension on
that vertical driving belt.

The foreman was worried because he
could not maintain the necessary speed
on the machines and had to shut down
until the engineer returned. I told him
if he would furnish some timbers and
some help I would keep him running all
right. He did this and then went up
to start what mills he could.

In an hour or so I had securely shored
down and braced the whole business fore
and aft and the mill was again in full
swing.

After sitting around for quite a while
to see that the timbers did not work loose
and fall over on the belt, or start some
steam pipe leaking, and also to give the
engineer an opportunity to return and
thank me — which did not happen — I left,
taking with me the satisfaction of having
rendered a good service.

O. C. Wilson.

New York City.

Lubricator Condensing
Chamber

In the August 15 issue. J. W. Dickson,
in reply to Mr. Wallace, says regarding
the lubricator condensing chamber that
it will condense a greater volume of
steam in a given time in its present posi-
tion than it will if placed 2 feet above
the lubricator. I do not see how the
position will make any difference.

I agree with Mr. Dickson that there
is no advantage in the operation of the
lubricator by placing the condensing
chamber in any other position and that
there is no need of draining the water
from the condensing chamber in refill-
ing; on the contrary, it should not be
drained.

If the lubricator is filled before it is
entirely empty it will start at once if the
condensing chamber is not drained, and
the condensing chamber will keep cool
and will not tarnish the polish.

I do not think the lubricator would
look as well with the condenser placed
2 feet above the lubricator, as Mr. Wal-
lace suggests, and there will be little or
no difference in the operation either way
so far as the position of the condensing
chamber is concerned. The chamber was
originally intended to be ornamental.

Many lubricators have no condensing

chamber, and are very good ones at that;
therefore, I do not believe the condensing
chamber is necessary. If it is used it
should be left where the makers put it,
on the lubricator. No trouble will be
had in starting after refilling if the water
valve is closed before the drain is opened,
and opened last before regulating the
feed.

J. C. Hawkins.
HyattsviUe. Md.

Teaching the Boy a Trade

Your editorial in the July 11 issue on
the above subject certainly contains much
food for thought, and impels me to make
a few suggestions.

There is no doubt but that if more at-
tention were paid to the boys' natural
inclination by the parents and greater
opportunities were provided by employers
and educators to properly shape and di-
rect their latent abilities, more bright
boys would endeavor to become skilled
mechanics than is now the case.

The old apprentice system of our fore-
fathers has practically ceased to exist,
a condition to be sincerely regretted as,
so far, nothing has been brought forward
to take its place. This loss had not been
felt until recent years, because the im-
portant positions have continued to be
held by the skilled men produced under
this system. Too much credit cannot be
given to those old-time master mechanics
who felt their responsibility to their ap-
prentices and made every effort to im-
part their knowledge to them. There are
many successful men of this generation
— now rapidly passing away — who laid
the foundations of their success under
such conditions.

M the present time there are very few
apprentices because, except in a few in-
stances, no effort is being made to teach
the boys a trade. Generally all that
these apprentices learn is what they can
absorb by personal contact with the work,
as the foremen and managers are too
busy and too much interested in increas-
ing the output and decreasing the cost to
consider the future welfare of the ap-
prentice and of the industry. That ap-
prentices do sometimes acquire sound
information is due more to accident than
to design; as to teaching them the knowl-
edge necessary to a thorough craftsman,
that seems to be out of the question.
These conditions have been in force so
long and the apprentice system has fallen
into such ill repute that it would take
years of patient effort to- bring it to the
position it had occupied if such a course
were considered to be advisable.

The present system of works manage-
ment is also a large contributing cause
for the scarcity of skilled mechanics. The
old system taught a trade .from the
ground up ; the new system, by its mani-
fold divisions of labor, frequently teaches
each mechanic only a single operation. It
does not require the ability to look far

September 26, 1911

POWER

487

into the future to see that such a narrow
system cannot produce broad-gaged fore-
men and managers. Since it is impos-
sible to find skilled mechanics when
needed, it is necessary to formulate some
plan that will appeal to boys of ability
and will give them the opportunity of
thoroughly learning a trade. This may
be done by the employers alone or in con-
nection with the public-school system.

It will be found upon further con-
sideration that no mere system for in-
creasing the number of skilled mechanics
will suffice to settle this problem unless
they are suitably rewarded. Unless the
reward is made in proportion to the ef-
foil demanded, few young men will un-
dertake the years of preliminary training,
and of these few the majority will after-
ward desert.

To come down to hard facts, the low
rate of compensation is the real cause of
the scarcity of skilled mechanics. An
increase at this point will be a step in
the right direction that will do more to
attract bright boys to the trades and to
keep them there than anything else that
can be said or done.

Guy Wise.

Philadelphia. Penn.

Jet Condensers

The writer was interested in the edi-
torial "Condensers," appearing in the
August 8 issue of Power. It calls at-
tention to the statement often made that
there is an element of danger in the op-
eration of a jet condenser because it is
possible under certain conditions to flood
the engine cylinder.

A few years ago I happened to be
employed in a street-railway power plant
which had cross-compound condensing
engines with jet condensers. The en-
gines, being direct connected and having
heavy flywheels, would run some five or
six minutes after the steam was shut off.

One night when all the cars were in
and the steam had been shut off the en-
gine that was running, there was a mis-
understanding of signals between the en-
gineer in charge and a new fireman who
was on duty. It caused the steam sup-
ply to the condenser to be shut off. The
engineer, who was at the switchboard,
which was on one side of the engine
room, the condenser being in the -base-
ment on the other side, noticed nothing
wrong until a severe pounding started in
the low-pressure cylinder.

This condenser was provided with an
automatic vacuum-breaker, but enough
water got into the engine to completely
wreck the low-pressure cylinder.

Automatic vacuum-breakers, as ordi-
narily furnished with jet condensers, will
break the vacuum in time, but not soon
enough to save the engine under these
conditions.

Therefore I advise engineers to tap
the exhaust pipe close to the engine and
put in a valve, so that the vacuum can

be quickly broken in case of need. A
1,'j-inch globe valve will do the trick.
A. S. Specht.
Belmont. Mass.

Steam Drum to Prevent Wet
Steam

Mr. Gilbert, who referred to a cement
plant in his letter in the issue of .August
15, will be pleased to hear that we have
entirely eliminated the priming trouble.
Mr. Gilbert and I spent many months
in investigating and experimenting on the
boilers and feed water to stop the prim-
ing, and as the trouble was considerably
lessened when using three boilers instead
of two, we came to the conclusion that
there was insufficient steam capacity in
the drums of two boilers, hence Mr. Gil-
bert's idea of an auxiliary steam drum.

The greatest cause of the priming and
burning of flues was the organic matter
in the feed water, which was at its worst
when pumping into the reservoir and at
the end of the year, when the water in
the reservoir was low and we were draw-
ing from the bottom valve. This organic
matter and mud were found, on opening
a boiler, to be so near the specific gravity
of the water that they might almost have
been-said to be in solution, and were cir-
culating with the water in the boiler, mak-
ing the use of the skimmers and the
blowing down of the boilers of very
little benefit. It also necessitated the
forcing of the boilers. After the priming
the engine valves would be choked up
with sodium chloride and mud, the former
being so much in excess as to lead us to
believe that it was this salt which caused
the priming. But even now that we have
eliminated the priming and are running
the boilers at 25 per cent, overload con-
tinuously, an analysis of a concentrated
sample still shows NaCI to run as high
as formerly.

To get rid of the organic matter, tem-
porary coke filters were installed until
we have completed our settling tanks,
and the water will then be treated with
lime and iron sulphate similar to the
system employed in the St. Louis water
works.

Another means of preventing our
trouble is by the use of an electrical ar-
rangement by means of which we syn-
chronize th? valves of our engines so
that one takes steam while the other is
exhausting.

These de-ices, together with the fact
that we run our boilers a shorter time
when possible and blow them down more
frequently, have entirely gotten rid of
the priming trouble.

Mr. Gilbert's idea would certainly help
in the case of other boilers in use in
this part of the country where the an-
alysis of the water shows no organic
matter but a considerably high amount of
alkaline salts.

W. J. Price.

El Paso, Tex.

Pager Gaskets

In reading the practical letters which
appear in Pow er from time to time, one
is frequently reminded of something sim-
ilar, or relatively similar, in his own
career, which otherwise would, perhaps,
remain forgotten. Many a valuable idea
has become lost because no association
of ideas occurs to restore the memory
concerning it. But men who read
Power every week are given plenty of
ideas to call back things that they had
done at some time or other, and they
should be glad of the opportunity of giv-
ing valuable information to a fellow en-
gineer.

Leroy D. White's letter, in the August
15 issue, on "Tarred Paper Gaskets"
made me think of the time that I used
up all the old drawings in the company's
drawing office, to make gaskets for the
tube plates of National water-tube boilers.
The asbestos jointing which we had been
using was not so satisfactory as might
be desired for that particular service, so
we conceived the idea of using old and
otherwise worthless drawings.

The gaskets were made of the proper
size and soaked in boiled linseed oil.
They never leaked in eight years, al-
though they were always made of draw-
ing paper and treated with linseed oil.

If the metallic surfaces are in fair
shape, drawing paper so used will make
an enduring joint. I offer this experi-
ence to readers for whatever it may be
worth. It is at least worthy of a trial.
CH.^RLES J. Mason.

Scranton, Penn.

Water Hammer

C. J. Harden, in the issue for August
8, gives a good explanation of the causes
of a boiler exploding when cut into a
steam line having a lower pressure than
that in the boiler. He also shows how
such accidents may be prevented.

However, he claims that the explosion
is not caused by water hammer and it
seems to me his whole argument is
against him in this respect. I think the
simplest and most practical way to knock
a hole in a boiler is to hit it with a ham-
mer, and as a water hammer is usually
about the only implement one will find
lying around inside a boiler with steam
up, it certainly must be the tool that
does the business. He is right when he
says that the water is lifted with great
force.

Now. if this water holds together in
an even sheet it will simply compress
the steam and there will be no explosion
provided the boiler is reasonably sound.
But. the water is more likely to burst
through the steam cushion, cspecislly in
the vicinity of the steam outlet, and there
results a powerful water hammer against
the boiler plate.

Fred Boone.

Vernon, Tex.

POWER

September 26, 1911

Trouble with Leaking Tubes

I read with interest Mr. Beaton's arti-
cle in the Septeinber 5 issue. Burnt
plates, tube sheets and tube ends, usually
caused by neglect to keep sufficient water
in the boiler or to remove the scale and
mud around the tubes are the cause of
many leaks. I once took charge of four
boilers which had been used only two
years. When I came the tube ends leaked
badly. There was much scale to remove
from these boilers at each cleaning, but
this should not have caused the beads
to wear away. The tube ends were found
to be very brittle when rolled with the
expander. Most of the men were new
to the plant, so it was hard to get any of
the history of the boilers. However,
after a few months I learned that one
of my predecessors on taking charge of
the plant had found the tubes to be filled
with one solid mass of scale. The scale
was removed but the tube ends were
badly affected. The only way these tubes
could be kept tight was to put into the
boilers, after each cleaning, 12 pounds
of bran or meal.

In some parts of the country the fuel
obtainable is very severe on the fire
sheets and the tube ends of internally
fired boilers. Also, the water may be of
the artesian-well kind and, being very
hard, has an injurious effect on the tubes,
making it necessary to expand and re-
calk them every year.

1 see no reason why through braces
should cause tubes to leak, for they could
not be badly affected by expansion or
contraction unless it were exceptionally
severe, as when feeding cold water di-
rectly into the braced part of the boiler.
If Mr. Reimers should place a scale or
straight-edge across the head near the
brace when the boiler is cold and again
when it is hot. he could determine with
the aid qf thickness feelers the amount
the braces draw in the heads by con-
traction. Gusset braces have been found
to cause leakage and fracture of plates
on account of their being too rigid.

One of the most stubborn cases of
leakage of boiler seams and tubes was
in a large office-building plant. The
plant had been in operation 18 years and
the boilers were replaced by six new
ones 66 inches in diameter and 18 feet
long. They were made in two courses,
making but one girth seam just back of
the bridgewall with the back sheet lap-
ping outside the front sheet.

After being installed for 10 weeks they
began to leak around the girth seams and
the tube ends. A boilermaker calked
the seams and expanded and beaded the
tubes. In less than a week the boilers
were leaking worse than ever. Grease
deposit was suspected and opening the
boilers a very small amount was found,
although every joint along the steam
main and piping throughout the engine
room showed signs of grease oozing
through the gaskets.

.^n examination of the return tank was
made and a little oil was found along
the water line. The grease separators
were all examined and the drip traps
were cleaned, but the only oil visible was
a few very small spots on the water in
the return tank. Finally, the oil and the
returns were analyzed and it was found
that the oil after entering the boilers
with the water, and even before entering
the boilers became thoroughly mixed with
it. This was overcome by putting in a
filtering system on the end of the return
pipes. Strange as it may seem, the oil
appeared to dissolve and settle in the
form of mud to the bottom of the boilers.

Here is a mystery. The old boilers
were in service 18 years land never
showed any signs of grease deposit or
leakage at the girth seams. If the grease
separators were in bad working condition
or the float valves stuck in their seats
this would allow the oil to accumulate
in the separators and fill them up; it
would then be carried through the heating
system back to the boilers. I think a
discussion of the effects of oil in boilers
may be of interest.

R. A. CULTRA.

Cambridge, Mass.

Installing Oil Tanks

W. W. Warner asks if any reader of
Power will give him an idea on how to
transfer fuel oil cheaply from tank cars
to storage tanks. The tank cars are 3
feet below the bottom of the storage tanks
and "it must be borne in mind that oil
is somewhat more difficult to handle in
freezing weather than in warm."

My experience has been with gold and
silver mines in the mountains, where
there were hillsides on which I could
build "switchbacks" in the railroad track
to get the tank cars above the storage
tanks. Mr. Warner might accomplish
the desired result by a trestle, in which
case gravity would help; but even with
the cars above the storage tanks, in
freezing weather the demurrage on the
car would likely be heavy without some
assistance by gravity.

Manifestly, Mr. Warner will have to
force the oil up hill through a pipe, and
in freezing weather it needs some force
to make it run down hill even. I have
tried putting steam coils into the tank
cars and heating the oil in that way for
two or three days to let it run out of a
4-inch opening at the bottom; it would
then have to be pumped up to the stor-
age tanks while warm if the storage was
above the car outlet. While the warmth
facilitates the pumping and the passage
of the oil through the conduits to the
storage tanks, this method takes too
many heat units and too much steam
energy. I have seen a "car house" built
over a tank buried in the ground. The
building was kept warm with stoves and
by the exhaust steam in heating radiators.

and the car was shoved into this house.
Possibly Mr. Warner might pump the
oil from the warm car house up to his
tanks in the same manner as is done with
any other method of heating.

Both of these methods of heating oil
in tank cars will accomplish results if
the expense is no object, but at the mines,
where we use compressed air under 80
pounds to 110 pounds gage pressure, I
have found it convenient and economical
to tap a small air line into the top of the
tank car and set the pressure up, on top
of the oil, as high as desired. The oil
will then flow through the 4-inch opening
in the bottom of the tank, and probably
would flow up to the storage tanks if the
pressure was high enough. This method
cannot be used with steam direct from
the boilers on account of the condensa-
tion. It is satisfactory only with air
pressure, and in warm weather will un-
load a car in a surprisingly short time;
even in winter, where the cars are above
the storage, the time of unloading a tank
is greatly shortened over any other
method.

The economy of it lies in the fact that
what air is put in the tank Is never
lost until the tank is empty, and it re-
quires just one tank of air to unload a
whole car. A small compressor run off a
countershaft or pulley could be installed,
using the car for an air receiver, and a
few minutes' run every hour would keep
the gage pressure at any desired figure.
Perhaps even a hand pump compressor
could be used, or if hydraulic pressure
can be had a water motor might keep
the pressure up on the tank. The prin-
ciple of the blow torch and the oil burner
is carried out one step further. Put the
pressure behind the oil and it will flow.

LeTSON B.^LLIET.

Tonopah, Nev.

Engine Runs with Steam
Valves Closed

The letter in the September 5 issue
by O. Lantz in regard to the engine run-
ning with both admission valves closed
is interesting and I would like to see a
couple of diagrams from the engine.

The expansion lines of the diagrams
undoubtedly should show very plainly
a serious leak in the valve.

I suppose the engine under discussion
is noncondensing, and I think it would
have been better had Mr. Lantz stated
the conditions a little more plainly, giv-
ing the details of the piping, etc.

If the steam valves admit steam after
they have been closed, the following
are the most common causes: Leaky
valves or seats, steam passing by the
ends of the valves, insufficient lap or
probablv, if the valves are double ported,
there is too much lap, admitting steam
over the top edges of the valve.

J. W. Dickson.

Memphis, Tenn.

September

1911

POWER

I.^Mie.i Weekly by tl.e

Hill Publishing Company

John- A. HiLL, Pres. and Trcas. ROB*TMcKEAS,Sec'y.

505 Pearl Street, New York.

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ter den Linden tl— Berlin, N. W. 7.

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Entered as second class matter, De-
cember 20, 1910, at the post office at
New York, New York, under the Act
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Of thi}i issue 31,000 copies are printed.

yone sent free regularly, no returnii from
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'ore Ifff. net eirruiatinn.

Contents iaoe

The Steam Turlilno in Girmnny 4(;i;

Convenient Oil I'linips 471

iJeBlgn <pf Steam I'ower I'lants 472

How the Engine Was Wrecked 474

t'sing Compressed Air in Steam Hoists,. 47.1

Centrifugal Force and Flywheels 47ti

Why Central Stations Catch Isolated

Plant Business 477

on In Wyoming 477

Power Development on the I.os Angeles

Aqueduct 478

A Novel Commutator I.ulirlranI 470

The Itemlngton Kerosene Engine 480

Preventing Holler Corrosion In Ritiiminous

fias Producer Planlt 481

Gasolene In the Lubricating Oil 481

Practical I.etlers :

Kerosene Oil a Protection to PIpos
and Pumps .... Erecting a Steel
Stack. .. .Combination Turbine Gen-
erator and Pump I'nII. .. .Sampling
and Analyzing Coal . . . . Keiuhed the
<v,ndenser .... Water Tank Signal

System Cost of Steam to the

Contractor .... Boiler Feed I'ump
Regulator .... Emergency Check

Valve Bepalr 482-484

DiitciisMlon l^^lters :

Ralicoek & Wilcox Headers. Tubes
and P.alUe W.ills Cosl of Fur-
nace I'pkeep. . . . Need of Well In-
formed Engineers. ... Emergency and
the Man. . . .I.iibrlentor Condensing
Chamlier .... Teaching the Boy a
Trade. . , ..let Condensers. . . .Steam
Kriim to Prei-ent Wet Steam...
Paper f;askels .... Water Hammer
. . . .Trouble with Leaking Tillies. . . .
Installing Oil Tanks.. .. Engine Uuns

with Steam Valves flosed 48.%-488

Kdllorlnis 4N!I-4!I0

Troubles of a Hot Water System and

Insperllon 4ii;;

Elevating Returns from Healing Colls. . . 41i.-,
Prime M.iver on Newly Applied Principle 4f>«

I'nionding Coal Cars 4nfi

rompniind Engines 407

Failure of Mlxe<I Pressure Turtilne In-
stallation 4Ji7

Give the Gases Room

Several years ago a boiler builder sent
a pair of boilers to a Southern manufac-
turer who used wood fuel. After a time
another pair of boilers was ordered.
When these boilers were shipped, by
some blunder a pair of cast-iron fronts,
having the firing doors and grate-sup-
porting brackets a foot further from the
shell than standard practice, were sent
with them.

It was not discovered until several
days after the boilers had gone that the
wrong fronts had been sent and the best
course of action to be taken in the case
was not clear. It was finally decided to
wait until the purchaser complained and
then send him the right front castings,
with profuse apologies for the error.

In due course of time a check cover-
ing the final payment was received, ac-
companying a letter asking for a price
on two more boiler fronts similar to the
last pair, to be used in replacing the
first ones. The letter said that the new
arrangement gave the fire more room to
burn, made less smoke and required a
great deal less wood for the same work.

This is just what should have been
expected. Wherever the flame comes in
contact with the comparatively cool sur-
faces of the boiler it is immediately ex-
tinguished, and that portion of unburned
gas goes up the chimney without giving
up all of its heat.

With anthracite and other short-flame
fuels containing only a small percentage
of volatile matter, the gases are all
burned without coming in contact with
the shell and the ordinary boiler setting
gives a fair degree of efficiency.

But for coals of the long flaming
variety, with a large volatile content, the
distance from the boiler shell should be
such that contact of the burning gas with
the shell is at least improbable.

Probably the best furnace for burning
ordinary bituminous coal with hand fir-
ing is the plain flat grate with a fire-
brick arch for the purpose of maintain-
ing a high combustion-chamber tempera-
ture. In short, the dutch oven in some
fonn will be found the most economical
furnace.

That furnace construction to be avoided
above all others for the burning of
coal having twenty per cent, or more of
volatile matter is the one with the boiler
directly above the grates and so near to
it that the flames touch the iron.

Gains in power-plant efficiency in the
future must come largely, if not almost
entirely, from the boiler room, and with
the improvement that will come when
the intelligent fireman feeds a furnace
intelligently designed for an intelligent
owner, the municipal smoke inspector's
occupation will be gone or the office will
become a sinecure.

Chimneys

Very tall chimneys have been char-
acterized by one writer as monuments
to the folly of their builders, and the advo-
cates of mechanical draft have endeavored
to prove that the chimney is practically
useless. However, in the face of this
and despite all arguments to the contrary,
the number of chimneys is increasing
and the number of them which are higher
than one hundred and fifty feet, and
whose increased hight and cost are not
justified by their efficiency according to
some writers, is rapidly increasing.

In the modern power plant the function
of the chimney is twofold: It supplies
draft and carries the waste gases to such
a hight that they will be dissipated in
the atmosphere without damaging the ad-
jacent property. This latter function is,
in many cases, the most important reason
for the existence of the chimney and
the draft it produces is a useful bypro-
duct. The biggest and highest chimney
in existence — fifty feet in diameter at
the top and five hundred and six feet
high — was constructed to carry off the
waste gases of the Washoe smelter. This
extreme hight, which later may be in-
creased to five hundred and fifty-six feet,
was adopted in order to discharge the
gases at such a hight that damage to sur-
rounding property would be eliminated;
furthermore, the base of this chimney is
on a high hill several hundred feet above
the smelter.

In and near cities is the natural loca-
tion of the large steam power plant. In
such localities real estate has a large
potential value for residential and busi-
ness purposes and it is absolutely neces-
sary to conduct the gases of combustion
to a sufficient hight to insure their
thorough dissipation without damaging
the surrounding property.

The difficulties which may result from
real or fancied claims for damages are by
no means imaginary. In Alontana the
Anaconda Copper Alining Company has
encountered nuitierous claims from
neighboring ranchmen for damages hased
upon the destruction of vegetation by the

490

POWER

September 26, 1911

waste gases from their smelters. A com-
mission, composed of three members, one
selected by the company, one by the State
of Montana and a third selected by these
two, has been appointed to investigate
the trouble. In Pittsburg the Jones &
Laughlin Steel Company has had con-
siderable trouble from claims concerning
the escape of ore dust from their blast
furnaces, which are located in the
Monongahela valley just below Oakland's
residential district. This dust is carried
into Schenley park and has caused con-
siderable trouble at the Phipps Conserva-
tory. The Carnegie Institute in Pittsburg
has found it necessary to adopt a very
extensive system of air filtration for the
ventilation of its museum and library in
order to eliminate dust and soot.

Numerous power and manufacturing
plants in various parts of the country
have found that claims for soot damages
to residence property were readily traced
to their chimneys. In many of these
cases while the individual claim was
small, their aggregate was large and
troublesome. One of the results of
soot distributed over the neighborhood
is a hostile public sentiment which may
make its influence felt in many devious
ways by the concern which has fallen
under the ban.

A tall chimney is not necessarily an
architectural monstrosity, but severe sim-
plicity is more effective than thistle-top
effects.

Making Good

One of the common complaints of chief
engineers against their assistants has
been that they -will not take responsibility
_ when difficulties arise, but at once call
for the chief, regardless of the hour or
the circumstances. Generally the trouble
amounts to but little. In one instance it
was the stopping up of the bottom con-
nection to a water column, a matter that
any engineer should have been able to
deal with without calling for assistance.
In another instance a flywheel worked
loose on the shaft and the chief was
called to superintend the tightening of
the nuts on the bolts in the split hub of
the flywheel.

The man who makes good must produce
results on his own initiative and he must
not confine his efforts to working out
problems along old. well beaten paths.

One engineer made good when he in-
stalled a line of steam piping in the con-
struction of which he incorporated ex-
pansion loops of his own design and
placed drop legs in the line to provide for
suitable drainage and assist in taking
care of the expansion of the pipe, in
spite of the assertion by other engineers
that the loops would not work, or if they
did. the joints would leak because of the
expansion and contraction.

In a certain small plant the engineer
wanted a damper regulator, but the firm

would not purchase it. He thereupon set
about making one which, when put to
work, kept the steam pressure within
a three-pound limit. This engineer is
now operating a larger and better
equipped plant and receives a higher
salary.

Another engineer desired to present
facts and figures to his employers and in
order to do so intelligently and accurate-
ly he worked out a system of report
sheets which were most complete and
would be a credit to any engineer. Thou-
sands of engineers have read of his
method of keeping his plant records. This
man would have no trouble in obtaining
a better position should he so desire.

The Lighting of Power
Stations

Power-station lighting is an old and
threadbare topic, and the only excuse for
referring to it again is the fact that, like
the strain of original sin said to have
been planted in the race some centuries
ago, its defections continue to make
trouble without any limit as to place and
person. One cannot explain why it is
that some of the lighting companies, most
progressive in equipping their customers'
establishments with first-class layouts of
lamps and shades, are such persistent
violators of the rudimentary rules for
illumination, not to mention good taste,
inside their own stations; but such is the
fact. With all that has been written
lately concerning illumination there
should be no need of again going over
the old ground and pointing out the abso-
lutely necessary practice of placing
lamps so that their direct and insistent
rays cannot glare into the human eye.
Screening the lamp or at least putting
it outside the range of normal vision
is one of the fundamental principles of
good illumination, and beyond this the
problem is merely one of detailed meth-
ods of obtaining the maximum illumina-
tion for a given cost, so far as the work
may be done in good taste. Yet the con-
tinued use of bare lamps in front of
switchboard instruments threatens the
eyesight of the operating engineer, handi-
caps him in taking readings rapidly and
accurately, and at a critical moment in
the synchronizing of generating units
or the handling of rheostats in connection
w-ith frequency changes may lead to
serious consequences.

The whole question of station lighting
is assuming more importance as the
value of machinery under the super-
vision of each employee increases. Sooner
or later it will be recognized that good
lighting is an instrumental factor in the
precision and efficiency of the administra-
tion of a modern generating station.
.Money is now spent in large amounts
to insure the utmost refinements of
switching service, remote control and

operating flexibility in general, and that
is as it should be; but without an ample
supply of properly controlled illumina-
tion the service is bound to fall short,
more or less, of the modern require-
ments of continuity and regulation. Par-
ticularly in important substations hand-
ling high-voltage service is rapid action
necessary in times of line difficulty. In
dealing with extra high potentials it is
necessary to spring to the station switch-
board at the first instant trouble ap-
pears outside the plant, and the correct
handling of the machinery so as to keep
the largest possible percentage of the
load from falling out demands a standard
of instrument illumination that is fre-
quently not in existence. Only less im-
portant is the use of reflector lamps in
front of pressure gages and water col-
umns in boiler rooms, and in connection
with all thermometers and important in-
dicating instruments used in auxiliary
operation.

The amount of electrical energy re-
quired for switchboard and other station
lighting is ordinarily comparatively small,
but in the course of a month it runs up
into a noticeable total of kilowatt-hours.
There ought to be a chance to economize
here by the use of tungsten lamps of low
candlepower and possibly of low volt-
age. In the latter case the filaments are
thick enough to promise long life, and
the activity of such lamps in station ser-
vice is distinctly of the long-hour class.
Very little has as yet been done with
the tungsten lamp of small size in power-
house service, but there is certainly a
chance to secure illumination by its use
at low expense, combined with a genuine
improvement in the character of the light
delivered. With all the recent progress
in electric-sign construction for sen'ice
by low' candlepowered tungsten lamps
there ought to be something done in bet-
tering switchboard illumination. It is
surprising what a couple of four-candle-
power lamps taking five watts each will
do in front of a good reflector when
placed above the scale of an important
indicating instrument.

.^^n engineer recently took charge of
a plant, the engine room of which was
one of those "show places" that so de-
light the eye. Turbines, engines, every-
thing, were decorated with an abundance
of brass pipe, railings, etc., and kept
highly polished. Within a week the new
chief changed all this, and two coats of
black paint took the place of the brass
polish. "I will find work in the boiler
room for the men who have been rub-
bing brass," said he. Possibly he went
a little too far, but he has cut 20 per
cent, off the coal bill. The boiler room
is now more comfortable and the work
easier, and it will not be so difficult to
hold first-class men. There is a hint
here worth a little thought.

September 26, 191 1

POWER

' -r^^. -t'- .

Boi/er Specifications

Give specifications for a 150-horse-
power boiler, to carry 150 pounds pres-
sure; diameter and length of the boiler,
the thickness of the sheet, diameter of
the tubes, thickness and tensile strength
of the sheet. The efficiency of the joint
is to be 87 per cent.

H. D. M.

The dimentions should be: Shell, 6
feet 6 inches diameter by 16 feet head
to head; shell plate, ,.-, inch tlnick; butt
straps, ;> inch thick; diameter of rivet
holes, It^t inches; tensile strength of
shell, 56,000 pounds; factor of safety,
5. There should be ninety-two 4-inch
tubes, twenty-two 1 '4-inch crowfoot
braces on each head above the tubes,
two ll<-inch through braces and two
lj<4-inch crowfoot braces on the rear
head below the tubes, and llxl5-inch
manholes in the top of the shell and in
the front head below the tubes.

Boiler Horsepoiver
What is a boiler horsepower?

H. E. H.
A boiler horsepower is the ability to
evaporate 34'/. pounds of water per hour
from and at 212 degrees.

Safety l\ihe Calculations
The area of a safety valve is 3 inches;
the lever is 36 inches long by ■}^xl'l^
inches; it is 3 inches from the valve to
the fulcrum; the cast-iron 6-inch ball
has a hole through the center '.■x2 inches
and is placed on the lever 30 inches from
the valve; what pressure will it take to
make it blow?

A. D. B.
Cast iron weighs 0.26 pound per cubic
inch; wrought iron. 0.27 pound. The 6-
inch ball contains

I13.0<1 — 6 — 107.9 cubic inches
and weighs

107.09 X 0.26 = 27.84 pounds
The lever weighs

0.375 y 1.5 X 36 X 0.27 = 5.46
pounds
The weight of the valve and stem are
not given and so will be neglected.

The pressures tending to hold the valve
to Its seat are the weight of the ball
multiplied by its distance from the ful-
crum plus the weight of the lever multi-
plied by the distance of Its center of
gravity from the fulcrum.

27.84 ^ 27- 751.68
5.46 y 18= 98.28
751.68 -f 98.28 = 849.96 pounds

Questions 3 re/

not answered unless

accompanied by the^

name and address oF the

inquirer. This page is

for you when stuck-

use it

tending to hold the valve to its seat. The
upward pressure per square inch neces-
sary to balance the valve is found by
dividing 849.96 by the product of the
area of the valve multiplied by the dis-
tance from the valve stem to the fulcrum,
844.06

3 X T,

■■ 94-44 pounds

Boilers for Given E?igi?ie

Give dimensions of a boiler for a 100-
horsepower throttling engine; a 100-
horsepower automatic engine; a 100-
horsepower Corliss engine.

B. G. E.

For a 100-horsepower throttling engine,
a boiler 66 inches by 18 feet with sixty
4-inch tubes; for a 100-horsepower au-
tomatic engine, a boiler 66 inches by 16
feet with sixty 4-inch tubes; for a 100-
horsepower Corliss engine, a boiler 60
inches by 18 inches, with forty-six 4-inch
tubes.

,^ ,- I. • r' • tlitckncss X strength. X e

Duty 0/ Pumping hngwe = — ^,d„7.^,actoF^n.

A double-acting pump has a plunger
26 inches in diameter and a 44-inch
stroke; the plunger has a piston rod 4
inches In diameter extending through
both cylinder heads. During a 12-hour
duty trial, the total heat supplied to the
engine was 188,765,300 B.t.u. The pump
made 64,800 strokes. The pressure in
the discharge pipe was 160 pounds. The
vacuum In the suction pipe was 10 Inches,
and the difference In level between the
gage was 12 feet. What duty was de-
veloped ?

D. P. E.
Neglecting the slip In the pump cyl-
inder and valves, there were

64,800 X 12 V 62.3 = 48,444,480
pounds of water
pumped against

160 y 2.3 4 12 4 11= 391 feet of head
48,444,480 v 391 - 18.941,791,680
foot-pounds
The duty of a pumping engine Is ex-
pressed by the equation

Foot pounds of -uork done X 1,000.000

Tolid liitit units consumed
then

18,941,701,680 X 1,000,000

^88:7^300 = ■°o.345,703

foot poutids duty
per 1,000,000 heat units supplied.

fi-^re Draiin Steam
What is meant bv wire-drawn steam?
J. O. C.

Steam is wire drawn when it is passed
from a higher to a lower pressure through
a restricted passage, as a partially opened
valve, the valve of a throttling governor
or pipes of too small area.

Safe M'ortiing Pirssnre
What Is the rule for finding the safe
working pressure of a boiler 6x18 feet,
J^ J -inch plate, 50,000 pounds tensile
strength, 70 per cent, efficiency of seam
and a factor of safety of 5?

F. G. J.
The safe working pressure of a boiler
is found by multiplying together the
thickness of the plate in inches, the ten-
sile strength of the material in pounds
per square inch and the efficiency of the
seam, and dividing the product by one-
half of the diameter of the shell multi-
plied by the factor of safety. As a for-
mula It is written:

Safe uorking pressure

thickness X strength X efficiency

radius X factor of safety
Substituting the numerical values and
solving

0.5 X 50.000 X 0.70

.^C' X 5

= 97.2 pounds

Vfiect of Inside Lap
What effect will an increase of the in-
side lap have on a plain slide-valve en-
gine?

H. T. C.
Compression is increased by adding in-
side lap to a plain slide-valve engine be-
cause the addition of lap brings about an
earlier exhaust closure and a later release.

Pump Air C.hamher
What change in the pipe connection
can be made between the feed-water
pump and the boilers to prevent the vi-
bration and pound In the pipe?

S. L. W.
Put a sufficient air chamber on the
pump or on the end of the boiler-feed
main and keep air In it.

POWER

September 26, 1911

Troubles of a 1 lot Water
/stem aiul I nsncttioii*

Sys

i\ IlM N. I:VANS

In the design and installation of hot-
water heating systems certain precautions
are necessary to prevent deterioration of
the piping and insure immunity from
leaks. The practice followed in the in-
stallation of piping for low-pressure
steam systems should be so modified as
to prevent annoyance and subsequent
expense, which can easily be avoided if
proper care is exercised. The main points
to be avoided are leaks, air pockets and
bypasses or short-circuits.

Leaks can be eliminated by proper test-
ing, inspection and selection of the ma-
terial entering construction. The fittings
should be of the heavy water pattern,
such as are required for sprinkler work,
of good iron and tapped solid with no
bushings as they invariably are the source
of leaks. The pipe for hot-water work
should be strictly wrought iron and own-
ers and contractors should be sure they
get it. It is policy to buy from the man-
ufacturer who rolls nothing but wrought-
iron pioe, inasmuch as when mills roll
both they are apt to ship either as it is
very difficult to determine between
wrought iron and very mild steel. Each
mill, besides the tags, has its peculiar
roll marks and if the pipe selected comes
from a mill manufacturing wrought-iron
pipe only, the easily inspected roll marks
will be a sure indication. Steel pipe is
much tiiore liable to pitting than wrought
iron, and the slight difference in cost
more than pays in better threads.

Where the heating surface is in the
form of coils it is sometimes advantage-
ous to order the pipe without threads,
with the couplings separate. The mill
allows something for pipe with blank
ends and where a sufficient quantity is
used to warrant a power pipe-threading
machine on the job, the cost will be in
favor of blank-end pipe.

Adjustable dies only should be used
on work of this character as it is impos-
sible to cut proper threads with solid
dies with the wide variation in the sizes
of pipe to be tapped. When the pipe is
so seamed along the weld as to damage
the threads, it should be discarded. All
nipples should be made of extra-heavy
pipe, and when the cutter leaves a bur on
the inside, the pipe should be reamed out

•<'ii|i.vriKlit('(l. I'.in. li.v Ini .\. I'.Viins.
TConsullln!; I'liKineor, liPtitlns.' mid powrr.
].-)(-. liiciiulwn.v. Now York Cll.v.

to reduce the friction. When the pipe
is furnished with mill threads and
couplings, tl-e latter should be reversed
to the opposite end of each piece when
used for coils or in full lengths and
each coupling leaded and made up tight.
All stretched couplings should be dis-
carded and all joints should have two or
three threads appearing when made up
as they are apt to leak if the threads go
to a shoulder.

When inspecting a job of this kind it
is a good plan to try a few joints at
random with a pair of tongs or a wrench
to find out if they can be turned. Work-
men are often careless, and these trials
will show the amount of sinew used in
making the joints. Loose joints are often
found to be the cause of leaks when the
job is tested. The steamfitter will de-
pend on a loose joint taking up after the
plant is in operation from his experience
with steam, but it is never the case as
the joint will leak worse after the water
commences to circulate.

A good lubricant should be used, as
white and red lead mixed with boiled oil
or some standard pipe grease. Nothing
in the nature of a substance to fill the
spaces of a loose joint should be used
as the joint will leak eventually.

Cast-iron radiators should be tapped
solid without bushings, although some
radiator companies claim that they can-
not furnish screw-nipple radiators with-
out bushings on account of assembling
the sections. Good push-nipple radiators
are preperable to screw-nipple radiators
with bushings. If bushings are used they
should be flush, with machine-cut threads
put in with a bushing driver.

All water radiators have a top and bot-
tom connection to each section, and the
supply connection is always made at the
top of the radiator. In this type of radiator
steain circulates 50 per cent, better than
in the regular steam radiator with a
single bottom connection, and the differ-
ence in price is very little. Owners and
architects would do well to insist on the
use of double-connection radiators,
whether steam or water were used, as

the system would be interchangeable at
slight expense and the circulation would
be better.

If push-nipple radiators are to be used,
the form of nipple and joint should be
carefully examined. The nipple should
be smooth, with a proper taper, and the
casting and nipple should be milled to
correspond. The metal used in the nipple
should be as nearly immune from cor-
rosion as possible. The thickness and
character of the metal comprising the
nipple whether push or screw will deter-
mine this to a large extent. It may be
advisable to break one of the sections
to find out the grain of the iron and the
position of the core; this will be unneces-
sary if the water test is made, as defects
of this character will show.

All radiators should be tested to 100
pounds water pressure before being dis-
tributed in the building independent of
any manufacturer's test or guarantee.
This can be done with a hand test pump
at very little expense. All radiators show-
ing evidence of leaks should be rejected
and if many sections break, showing in-
dications of the use of a poor grade of
iron or displaced cores, the whole ship-
ment should be rejected; inasmuch as
these defects may not cause some of the
individual radiators to fail under test,
nevertheless it would be taking a risk
to install even one radiator of a lot de-
veloping the above faults. If the above
precautions are observed, trouble from
leaky radiators or broken sections will
be unknown, and experience usually
proves that there is no trouble, but the
cost of testing is an exceedingly small
percentage of that engendered by replac-
ing ten or twenty thousand feet of de-
fective radiation when the system is in
operation and the building is occupied.

When the piping mains and runouts
are completed, and before the radiators
are connected, the system should be given
an expansion test with 50 pounds steam
pressure. The gage should be placed at
the return end farthest from the steam-
supply connection. The job should be
thoroughly inspected for faults, and all
places where expansion has not been suf-
ficiently provided for should be so rear-
ranged that the piping will be free to
move.

After the expansion test, 100 pounds
water pressure should be used as a pres-
sure test and all leaky joints taken apart
and fixed. In case the hight of the
building requires a greater pressure than
100 pounds, the radiators will have to
be designed specially for the lower floors.

September 26, 1911

P O \V E R

493

This pressure is close to the limit of
what the commercial cast-iron radiator
will stand without special construction.
The working pressure is reduced as the
top of the system is reached.

After the radiators are connected a
final test should be made with the same
pressure, viz., 100 pounds, care being
taken to remove all air from the system
as completely as possible. The water
should remain on the system under pres-
sure three or four days to determine
the rate of leakage by the drop in pres-
sure. The apparatus may be taken in
sections or one building at a time if there
are several. Sal ammoniac placed in the
system or calking threaded joints and
various other devices are only makeshift
remedies for a leaky system of piping as
the leaks will reappear again in time.

Where coil surface is used it may be
tested with the piping or when possible
the coils may be built at the bench and
tested in the same manner as the radia-
tors. If steam pressure is available, an
efficient method of testing is to connect
each coil and let the warm condensation
from the steam accumulate, filling the
coil with water under pressure.

All valves should have large stuffing
boxes with a follower in the gland to
hoW the packing. The metal in the body
should be of sufficient weight so that the
steamfitter will not strain the body in
connecting the valves. All radiator and
riser connections should be made with
right and left threads; no unions should
be used either on the radiators or the
piping. Screwed joints with couplings
are preferable on the main pipes with a
sufficient number of bolted flange unions
for disconnecting without an excessive
labor expenditure; flanged fittings are
unnecessary except for plant connection.

Heaters will give very little trouble
from leaks if proper instructions are
given the builders as to the steam and
the water pressure under which fhe sys-
tem will operate. A test at 200 to 250
pounds will be ample for the steam and
water spaces in the live-steam heater,
depending on the boiler pressure. The
exhaust heater should be tested to 150
pounds in all water spaces and 50 pounds
in the steam spaces. At the same time it
should be air tight if used in connection
with a condensing engine. Boilermakers
as a rule are faithful in making these
tests as they can be held responsible for
leaks and it is expensive to repair them
after installation.

If desired, the heaters can be tested
with water pressure when the final test
is made on the system by disconnecting
the drip from each heater and noting if
water appears when the pressure is ap-
plied. A leaky heater should be repaired
at once as the boiler or system is liable
to be flooded, depending on the dilTcrence
In pressure between the water and steam
spaces.

Feed-»'ater heater manufacturers gen-

erally prefer to put the water through the
tubes with the steam outside. In build-
ing iron-tube heaters it is customary to
reverse this order on account of con-
struction. The exhaust heater has a large
diameter; therefore it becomes expensive
to make it tight so that the lighter pres-
sure is within the tubes, and the heavier
water pressure is held between the tube
sheets with the expanded tubes. In the
live-steam heater the same practice is
followed, but as the diameter is much
less the practice can be reversed if de-
sired. Two-inch charcoal-iron boiler
tubes are found to be the most economical
size for surface in these heaters unless
they are exceptionally long.

The large area around the tubes allows
a high velocity through the heater with a
minimum drop in friction head. This is
a contrast to passing the water through
very small tubes at a high velocity with
a corresponding drop in friction head of
10 or 20 feet.

If the foregoing methods of testing and
inspection are followed faithfully the re-
pair bill on the piping system of a water

Fig. I. Am Trap

job will be less than for any other sys-
tem.

All mains should grade up in the di-
rection of the flow of water, as the air
will not work back agfinst the current.
Provision should be made to relieve the
air at all high points by automatic air
traps, but using as few as possible. Any
good drain trap turned upside down and
so constructed that the valve is above
the water level when closed will answer
the purpose. If the trap valve is not
out of the wafer when closed, a slug will
be blown out each time it discharges;
It should be sn connected that a
vacuum cannot be produced in the trap
when it is closed and hold the water level
higher than that in the system, thus pre-
venting its operation. The discharge
should in any case be connected to some
point so that if it docs leak it will do
no damage.

A sketch of a common form of .'ir trap
is shown in Fig. 1. These must be care-
fully tested before being put in place
as they are very liable to leak and not
seat properly.

Dirt will tend to accumulate in the out-
let when the traps do not operate for a
considerable time; this dirt works down
on the seat of the valve and prevents
it from tightly closing. For these rea-
sons the reversed steam-drain trap with
its float and lever will give greater sat-
isfaction, there being more pressure to
seat the valve.

When risers are connected to the sup-
ply main the runouts should be taken
from the bottom and be so graded down
that an air pocket cannot be formed at
the top of the riser and shut it off. This
trouble may be further aggravated if the
riser expands upward. Radiators can be
connected to mains where convenient and
thus relieve the system of air, and, al-
though not automatic, the remainder of
the job is not interfered with beyond the
one radiator. All radiators should be
provided with key air valves whether
needed or not. Where mains are reduced,
eccentric fittings or reducers should be
used so that the level of the top of the
pipe will be maintained without air
pockets.

The piping should be so arranged and
sized that no bypasses or short-circuits
occur. The velocity necessary on a proper
working hot-water system should be some-
thing over 5 feet per second in the
mains, depending on the size, distance
and total head on the pump.

It is good practice to run individual re-
turns from each building of a grouo sep-
arately to the pump, using a common
flow pipe. This gives an opportunity of
separate regulation for each building, and
the cost of the separate returns over one
large main will not be sufficient to offset
the advantages gained. A valve and
thermometer should be provided at the
header for each return.

The return from any section should
start from the first unit connected to
the supply main and increase in size as
the supply main diminishes. The above
features are very important in designing
a system of this type inasmuch as it
equalizes the flow where the exact size
of pipe cannot be used because of the
large differences in capacities between
some of the commercial pipe sizes.

Lock stop valves should never be used
to equalize the flow for different sections
or radiators; it cases where this is made
necessary the arrangement of mains is
at fault. On a large job it is impossible
to set these lock-shiela valves to give
perfect satisfaction under all conditions
and any change in the setting throws the
whole system out. Individual regulation
of the different sections should be at the
main header in the engine room.

If the mains arc properly designed
according to the friction head, quantity

494

POWER

September 26, 1911

of water and distance, the lock-shield
valves will be unnecessary.

The placing of these valves is the same
thing as using resistance in an electrical
line to obtain the proper voltage for in-
dividual lamps when the wiring design
is defective. The most frequent mistake
in designing this class of system is the
use of too large mains and pumps with
too little capacity. At the same time,
the high velocities increase the liability
•of bypassing and require a more careful
•design in piping arrangement.

When additions are made to a hot-
water plant care should be taken that
the drop in head for all sections is as
nearly equal to that of the pump as is
possible. When too large a main is used
on an existing plant it acts as does a
short-circuit on a dynamo; the head and
speed of the pump are constant and
the increase in gallons due to enlarging
the main overloads the machine. When
the large branch is throttled to equalize
the flow, that particular building will
have a sluggish circulation, due to the
low velocity. If the building added is too
large for the existing plant the pump
should be modified to suit the changed
condition.

The same velocities cannot be used
for the mains throughout on a hot-
water system on account of the wide
range in loss in head per unit distance
of length for the different pipe sizes. The
mains cannot be designed properly ac-
cording to a constant number of square
feet of heating surface for each com-
mercial size, as the drop in temperature
on the system, head on the pump and
distance vary the discharge of water. A
2-inch pipe may take care of 2000 square
feet of surface in one portion of a plant
and be too small for 1000 square feet
in another section.

These points are mentioned as many
plants have been laid out on this basis
and may have worked fairly well, but
due to poor and unequal circulation the
main advantages of the system are lost,
viz., small drop in temperature, low
temperature of outboard water in ex-
treme weather. The entire system may op-
erate on 10 degrees higher temperature
of water just to meet the requirements
of a small percentage of the heating sys-
tem.

The proper discharge in gallons and
total head should be carefully deter-
mined in advance so that the pump man-
ufacturer may furnish a properly de-
signed pump. It is then good practice
to see that he delivers what is called
for by measuring the head and gallons
after installation. Many cases have oc-
curred where the manufacturers' test
curves showed proper design and when
the apparatus was installed an overload
was found on the named capacity and
head. A well proved friction formula
should be used to detemiine the capacity

and the head for the different mains in
all hot-water systems of this class.

One of the frequent objections ad-
vanced against the hot-water system is
the deterioration and pitting of the iron
in heaters and piping, due to the action
of the water. This can be avoided by
using the same water over and over with
the minimum of waste and leakage pos-
sible. If the water from any cause is
changed in the system to any consider-
able extent it will cause rapid deteriora-
tion in the piping. Attaching a hose to
the system to obtain warm water for
washing purposes should be prohibited
for the above reason and the fact that the
heating capacity of the heaters would be
interfered with to the extent of the
amount of new cold water introduced to
replace that drawn off.

Leaks from automatic feeders and
leaky draw-off cocks connected to the
sewer are a prolific source of trouble, as

into the system, additional air in solution
is driven out of the water and peroxide
of hydrogen is formed which is a very
active oxidizing agent.

Due to the possibility of leaking draw-
offs, it is safer practice to place the ex-
pansion tank in the engine room at the
base of the system under the immediate
supervision of the engineer. The latter
will then be cognizant of any change
in the water level of the system whether
the system is losing water or not. In
small installations and places where
the construction compels the use of the
overhead expansion tank with the water
feeder, it should be arranged as in Fig.
2 and be frequently inspected after it is
in operation.

The city water pressure should be
tested carefully to see that it is great
enough to flow into the system against
the static head as it sometimes fails, leav-
ing the system partially empty. The expan-

F'G. 2. Overhead Expansion Tank

the leaks cannot be observed. The auto-
matic water feeder is a device to supply
water to the system, and is placed on
the expansion tank when it is at the
highest point of the system to keep the
water level constant and the system full.
This combination would keep the system
full when at the same time a Jj-inch
stream of w-ater may be passing through
the system for months. In all cases of de-
terioration of piping or heaters that have
come to the writer's attention the trouble
could be traced to outside water enter-
ing the system for a considerable period.
The water, after being used in the sys-
tem for some months, becomes charged
with hydrogen gas which will burn at the
air valves when the system is drawn
down. This hydrogen gas. in small
amounts, comes from the dissociation
of the water under the continued action
of heat. When new water is introduced

sion tank in all cases should be con-
nected to the return or point of lowest
pressure when the pump is in operation
as any other point is liable to give a
false water level.

Experience has proved it to be the
best practice to keep the system full dur-
ing the summer as the water, with all
air excluded, will act as a protection to
the piping against deterioration. The
system should be drawn off and flushed
out once a year, say two or three weeks
before the end of the heating season.
The few days' operation after refilling
will give an opportunity to exclude all
possible air, and the system is then ready
for instant operation. It is desirable
sometimes, even in summer, to start up
the heating system with a low tempera-
ture for a few hours, especially during
a long period of damp weather. This is
easily done with a water system, while

September 26. 1911

P O ^' E R

495

with steam it would be a lot of trouble and
would cause almost as much discomfort
from excessive heat as from dampness.
Due to the practice of using low water
temperatures and large differences be-
tween the supply and return on gravity
water systems, the idea has become
prevalent that hot-water systems require
more radiation than for low-pressure
steam. This is not so as the circulation
of steam, even when vacuum is applied,
is apt to be hindered by air at times, or
if the pressure is very low and the con-
nections are small, a vacuum may be
produced in the radiator, thus cooling a
portion of the surface because of the
heavy condensation and inadequate
steam supply. This occurs often on in-
direct radiation with cold air supply.

In the case of hot water with forced
circulation, due to the high specific heat
of the water and a positive and rapid
circulation, the transmission of the heat-
ing surface is greater than with steam
for the same temperatures. If the water
is operated at a temperature of 200 de-
grees average, with a drop on the system
of 20 degrees or less, the same amount
of radiation will be ample that would
be required for a steam system operated
at atmospheric pressure, or 212 degrees.
The temperature of the circulated water
is determined entirely by that of the
gases or steam used in the heaters. If
high-pressure steam is used with no ex-
haust the water may be circulated up to
280 degrees and a corresponding reduc-
tion made in the amount of heating sur-
face installed over a system designed to
operate on 200 degrees and below.

It is safe to calculate the radiation
for water systems of this type in the same
manner as for steam systems with the
same temperature and corresponding
pressure, with the added assurance of
a positive circulation.

It is advantageous to operate water
systems at about 10 pounds greater pres-
sure than the static head of the system.
If the water is to be operated above 212
degrees, say 280 degrees, this pressure
would have to be increased slightly be-
yond that corresponding to the steam
pressure to keep the water in a liquid
state.

All hot-water jobs should be protected
from excessive pressure by a nickel-
seated, brass, water-relief valve on the
return set at the maximum pressure al-
lowable on the system. Under no con-
dition should the outlet of the valve be
80 connected as to prevent annoyance,
as when it operates the system requires
immediate attention. Separate pop valves
are sometimes placed on the pump cas-
ings for additional protection. These
pop valves should be tested at intervals
and only the very best of valves should
be used for this purpose as the seats
are liable to stick on the cheaper grades.

In the design of the pump casings suf-
ficifint metal should be used to stand the

greatest static head on the system. The
standard pump may be all right for the cir-
culating head and too light for the static
pressure. These data should be given the
manufacturer that he may strengthen the
casing if necessary. Solid follower
pumps are very inefficient and it is prefer-
able to use high-speed hollow bronze fol-
lower turbine pumps with motors or
steam turbines for prime movers.

The necessary repairs to radiator con-
nections and returns of steam-heating
systems are well known, also the noise
from water hammer when the steam is
turned on. The repairs are made neces-
sary by the sudden heating when steam
is turned on a cold pipe, which causes
expansion strains. The condition is ag-
gravated by the water from ihe con-
densed steam flowing on the bottom of
the pipes with the steam on top. causing
sudden and unequal strains on the joints.
Due to the above occurrences water ham-
mer on a steam job is often associated
with the possible damage of flood from
the hot-water system. In the latter case,
as the system is full of water heated
gradually under pressure, there is no pos-
sibility of sudden expansion strains,
water hammer or noise at any time.

The question of the possibility of freez-
ing is invariably introduced when hot-
water systems are under discussion. As
the water is under considerable pres-
sure and free from air. it would require
a somewhat lower temperature than 32
degrees to freeze it. When circulation
is maintained, even if no heat were in-
troduced, the water would not freeze.
Water has a density 1700 times that
of steam at atmospheric pressure and
each pound weight of steam has 1000
B.t.u. in latent heat which is available to
prevent freezing. The chance of a water
system freezing would compare with a
steam system as the temperature of the
water above 32 degrees multiplied by

the system can be drained quickly if de-
sired. The return pipes on steam sys-
tems have been known to freeze while
the apparatus was in full operation.

The hot-water system has more or
less circulation after the pump is stopped.
due to the inertia of the water and the
cooling effect at different points in the
system, which cause an added flow to
regain its equilibrium; this would tend
to prevent freezing for at least 48 hours.
In a certain case in an open shop-build-
ing plant the pump on a new system
broke down before the relay pump had
been delivered. The heat was off the
system 48 hours, and, although the ther-
mometer outside was at zero and the
water was not drawn off, it did not freeze.

It is not recommended that these
chances be taken, but it was expected
that the pump would be repaired at
any minute during the interval of the
shutdown, and if the system had been
drawn down it would have been danger-
ous to fill it with cold water until the
weather moderated. A new system should
not he tested or filled during extreme
winter weather because no circulation can
be produced by the pump until the piping
in full.

LETTER

Elevating Returns from Coils

It was desired to return the condensa-
tion to the boiler room from steam coils
located in a dry kiln about 200 feet dis-
tant. It was naturally supposed that a
pump would be required as it was nec-
essary to elevate the condensation 15
feet before it would flow into the tank
in the boiler room.

The tank carried a pressure of about
four pounds against which it would be
necessary to discharge, and a back pres-
sure of only one pound or so could be
carried on the coils in the kiln.

Trap CoNNfcrinNs for Rli:vatinc Re, urn?

1700 is to 1000. These figures are all
in favor of the water system. True but
the amount of water in the steam system
would be proportionally small and this
would freeze in a shorter space of time.
A water system left for a long period
of time without heat would freeze and
would burst with corresponding damage
in the same manner as the plumbing or
sprinkler work; therefore drawoffs should
be provided in the same manner so that

A high-pressure trap failed to work and
the arrangement shown in the accom-
panying illustration was finally devised.
The condensation was passed through
a bucket trap into an old-style Curtis
ball trap and discharged through a back-
pressure valve to the tank. The ar-
rangement of the piping is self-explana-
tory.

W. D. LaBadie.

South Bend, Ind.

496

POWER

September 26, 1911

Prime Mover on Newly
Applied Principle

Dr. Nikola Tesla is giving considerable
publicity to the exploitation of a newly
applied principle in the design of tur-
bines, centrifugal pumps and other ap-
paratus of a similar nature.

It has been demonstrated that to obtain
the maximum economy in the employ-
ment of a gas or liquid as an agent for
converting energy into mechanical power,
changes in velocity and direction should
be as gradual as possible. To reduce
the losses due to impact which occur
in the present design of steam turbines,
waterwheel, centrifugal pump and the
like. Doctor Tesla substitutes plain disks
for the bladed disks and vanes now used.

Every fluid, whether a liquid or a gas,
has the two physical properties of co-
hesion and adhesion and it is due to these
that the new apparatus can be made to
work. The accompanying figure illus-
trates the design of a centrifugal pump
based on the new application. The im-

nature of the fluid to be pumped and the
head against which it is to be forced.

In a steam, water or air turbine the
conditions are precisely the same only
the operation is reversed, the fluid com-
ing to the machine under pressure and
passing through at a high velocity causes
the disks to rotate.

According to Doctor Tesla, some- of the
advantages of this new type of apparatus
are, extreme economy, simplicity of con-
struction and operation, low maintenance
and, what is most important in marine
work, reversibility.

Unloading Coal Cars

By a. D. Williams

In thousands of places may be seen
a gang of men shoveling coal over the
side of a car or a wagon. In a small
plant the expense from this item may
not be large, but as the fuel bill grows
the cost of shoveling becomes a serious
item. Usually, the coal must not only be
shoveled out of the car but it must be

LONCITUnlNAL AND TRANSVERSE SECTIONS OF PlI.MP

peller consists of a number of plain cir-
cular disks keyed to the shaft and re-
volving in a volute casing which is not
dissimilar to the casing of an ordinary
centrifugal pump. Parts of the disks
are cut out so as to form curved spokes
at the center. The object of cutting out
these portions is to allow the liquid
which is being pumped to penetrate
readily to the center of the impeller.

Due to adhesion, particles of the liquid
tend to stick to the surfaces of the disks.
But, due to the centrifugal force im-
parted to the water by the rapid revolu-
tion of the disks, there is a tendency of
the particles to fly out toward the rim.

The result is that the particles are
made to flow with increasing velocity in
a spiral of increasing diameter until they
are flung off at the rim of the impeller.
Because of cohesion, particles not in di-
rect contact with the disks are thrown
off in the same way. The number and
size of the disks and the speed at which
they run as well as the distance between
adjacent disks are determined by the

thrown through a door in the side of the
building over a sill 8 or 10 feet above
the ground. Now, the question is, where
does it become economical to do away
with the shoveling? A carload of coal
usually weighs from 40 to 50 tons (89,-
600 to 112,000 pounds), and will run a
100-horsepower plant about one month
on day turn. The car, however, must
be unloaded in 48 hours to avoid the
demurrage charges of about SI per day.

Shovelers are generally paid from $1.50
to Si. 75 per day of 10 hours. Under or-
dinary conditions, one man will handle
from 50 to 60 pounds of coal per min-
ute over the side of a car, or from 3000
to 3600 pounds per hour and 30,000 to
36,000 pounds per day. Under a com-
petent foreman, the rate of unloading will
increase to 50,000 pounds per day, or 83
pounds per minute, and a picked gang
will exceed this rate, though the rate per
man will be increased about 20 per cent.

Even this last figure is not the inaxi-
mum when firing a locomotive, as the
coal is pulled down from the tender and

thrown on the fire; and one man, opening
and closing the fire door himself, will on
some runs handle 117 pounds of coal
per minute, or 7000 pounds per hour.
This work is strenuous while it lasts, but
a run fired at this rate rarely lasts over
four hours and the fireman has a 24-hour
layover at the end of the trip. The
locomotive fireman is also paid more than
SI. 75 per day of 10 hours.

The best shoveling record for handling
coal from a high-sided gondola which has
come to the writer's knowledge was made
by six men, who unloaded 80,640 pounds
of coal into a hopper in 44 minutes. This
was at the rate of 305 pounds per min-
ute for each man, or 18,300 pounds per
hour. This coal had to be placed in a
track hopper intended for use with bot-
tom-dump cars, which did not tend to
facilitate the speed of handling. This
rate probably will not be greatly ex-
ceeded, though the men were not played
out by any manner of means.

Assuming that 4000 pounds per hour
can be unloaded per man, the cost will be
4.375 cents per 1000 pounds of coal. As
there are approximately 300 working days
in the year the annual wages of one
man will be S525, which is the annual
interest upon SI 0,500 at 5 per cent. But
as there are other charges besides in-
terest the saving due to the displacement
of one man would only justify an in-
vestment of about S2000 in coal-handling
equipment.

Where one man can unload all of the
coal required for a plant he is probably
the cheapest and most economical un-
loader which can be employed. At least
one man is required to operate a coal-
handling machine even of the simplest
kind, though this duty may only require
a portion of his time, but a man intelli-
gent enoiigh for this purpose is usually
paid from S2.50 to S2.75 per day. Gen-
erally two or three men are necessary to
operate a coal-handling plant, one to take
care of and operate the machinery and
one or two laborers to clean up after
the machine.

Track hoppers sufficient to permit the
unloading of several cars at a time will
not cut down the number of men re-
quired much below three, as coal will
frequently be delivered in hopper-bot-
tom gondolas instead of bottom-dump
cars, which require a large part of the
load to be shoveled into the hoppers. In
winter the coal will freeze in the cars
in northern latitudes and may even have
to be broken up by explosives or thawed
by a steam hose. Where the coal is
handled with grab or clamshell buckets
one man must operate the hoist and an-
other trim up after and guide the bucket
when cleaning up the cars. While these
buckets will not work in close corners,
they will take out from 80 to 85 per cent,
of the coal under favorable conditions.

The several elements which affect the
cost of coal-handling equipment are:

September 26, 1911

POWER

497

Hourly capacity necessary, storage capa-
city to be covered, and vertical and hori-
zontal distances covered.

Storage capacity will cost from S2 to
S15 per ton of 43 cubic feet. The hourly
capacity wiil be fixed by the sizes of
the buckets and belts and their speed
limitations, while the hight of lift and
the distance the coal must travel will
fix the length of the conveyer units.

Locomotive cranes with grab buckets
are often employed, but their maximum
effectiveness can only be realized when
they can be spotted at one point and
limited to lift and swing.

Gantry bridges with buckets are sub-
ject to similar limitations, hoisting and
racking being their effective service.
When either of these devices is used to
transport coal along the runway the use-
ful load is such a small proportion of
the dead load and the speeds are so low
that the amount of useful work will be
extremely slight.

Belt, bucket and scraper conveyers are
used for horizontal and vertical trans-
port. Each has its special province and
overlaps the others. The type to be used
will depend entirely upon the local diffi-
culties to be overcome.

Compounding the Steam

Engine

By W. H. Booth

The early compounding of steam en-
gines in Great Britain differed from the
practice in America in that the British
custom consisted almost entirely in the
addition of a high-pressure cylinder to
an old engine, no change being made
in the low-pressure cylinder and the
power of the engine remaining the same.

Some of the earliest compounding was
done by a man named McNaught and
was always termed "AlcNaughting." He
took in hand the old factory beam en-
gines as he found them at work in the
earlier cotton mills. Many of these en-
gines had been originally designed to
work with boilers carrying only seven
pounds of steam pressure. He found
them working with 30 pounds, consid-
erably throttled, for the engines would
not stand 30 pounds on their pistons; as
it was, many of them lifted their founda-
tion walls. Sometimes the heavy pier
of weighty masonry under the cylinder
would lift as the steam entered the top
of the cylinder; at others, it would be
the crank wall that lifted, and more often
, the cross wall under the columns which
supported the entablature beam under
the rocking beam center would lift as
it was exposed to a double effort of the
beam's leverage.

McNaught added a small cylinder
which he placed half way between the
beam center and the connecting rod.
Thus, when the low-pressure cylinder

tried to lift the beam wall, the high-
pressure cylinder would pull it down-
ward. One cylinder counteracted the
other and the beam-center bearings were
relieved of stress. So popular was this
method of compounding that it was quite
a usual practice to make new compound
engines on the McNaught plan. An-
other system of compounding was to
place an inclined cylinder the rod of
which took hold of the crank pin of the
beam engine, and another common ar-
rangement was to employ a quick-run-
ning horizontal engine, the exhaust of
which passed to an old beam engine. The
horizontal engine might or might not be
intergeared with the beam engine.

At one place familiar to me an old
Boulton & Watt side-lever marine en-
gine, by HO means an uncommon type of
engine in cotton mills, took its steam
from the exhaust of a pair of vertical
engines.

In all these various compoundings it
was always the addition of high-pres-
sure cylinders, and many old engines
were thus worked from boilers carrying
80 pounds pressure. The compounding
thus enabled one to obtain the economy
of higher pressures and it also saved
the outlay for an entirely new engine,
giving an extended lease of life to an old
and weak engine at a time (1860-64)
when cotton manufacturing was passing
through a nonprofitable period.

Failure of Mixed Pres.sure

Turbine Installation

By C. a. Tupper

The disastrous consequences of rush-
ing into the use of mixed- or low-pressure
steam turbines without first ascertaining
with reasonable certainty whether the
conditions are suited to such an installa-
tion, are illustrated by a case recently
reported from one of the mining districts.

The company operates a large property
which includes a number of very deep
shafts; and for these there have been
provided in past years some of the most
powerful hoisting engines built. Not long
ago it was decided to equip the mine
with electric haulage for underground op-
erations, and the first idea appears to
have been to purchase the necessary
current from a local power company.
There were no generating units directly
at the mines, and, besides the steam
hoists, the company had only compressors
in service. No pumps were required, as
very little water penetrated the workings,
and this was baled out and hoisted in
buckets.

While the matter of electric power was
under consideration, it was suggested that
the exhaust from one of the big hoisting
engines be utilized in a mixed-pressure
turbine driving an alternating-current
generator. Turbine manufacturers were

very much interested, and they appear
to have made a careful examination of
the operating conditions with the result
that all but one refused to put in a pro-
posal, stating that the scheme was com-
mercially unfeasible. The mining com-
pany also was not sufficiently impressed
with its practicability to warrant its pur-
chasing a low- or mixed-pressure tur-
bine; and, for reasons of its own, which
were probably connected with plans for
future extension, it did not care to install
a standard high-pressure unit of any
description.

The engineer who conceived the idea
of using a mixed-pressure turbine was,
however, not to be discouraged; he hit
upon the novel expedient of organizing
an independent operating company to in-
stall the turbine unit, purchasing from
the mining company the exhaust steam
and whatever live steam might be needed,
and selling to the latter company the re-
sulting electric power.

The turbine selected for the service
was a mixed-pressure machine to operate
condensing at a steam pressure ranging
from 16 pounds to 100 pounds absolute
and a back pressure on the hoisting en-
gine of 5 pounds. It was coupled direct
to a three-phase, 60-cycle, 2300-volt, al-
ternating-current generator, running at
1800 revolutions per minute. The ex-
haust steam was taken through a r.. gen-
erator and live steam was automatically
shut off or admitted as the exhaust steam
became available or not.

The hoist operated in balance with
very heavy skips, and when the loaded
skip had ascended part way the steam
was shut olT from the cylinders of the
engine. Meanwhile, the exhaust was con-
siderable and it puffed into the regen-
erator with cyclonic violence. There was
enough to run the turbine for a very
brief period; then the machine had to
depend on live steam until the exhaust
from the hoisting engine commenced
again. Taken altogether, the power of
the unit was developed almost wholly
on live steam. Furthermore, the back
pressure on the hoisting engine, instead
of being only 5 pounds, as predicted,
was about double that amount, thus ma-
terially lessening the power developed
in its cylinders. Under the circumstances,
the use of the turbine would appear to
have resulted not only in no economy but
in an actual loss.

The facts were soon spread abroad and
have caused unwarranted injury to the
legitimate claims of low-pressure tur-
bines in the extensive district affected, for
the reason thaf the power-using public
does not take into account the circum-
stance that this unit was installed in a
place for which it was not adapted. Re-
cently the lurbo-gcncrator was put out
of commission by an unavoidable acci-
dent and it is slated that some changes
will be made in the arrangement of the
plant before the plan is tried again.

498

POWER

September 26, 1911

"Inertia" Corliss Valve Gear
and Improved Dashpot

A new type of admission-valve mech-
anism, the "inertia gear," is built by the
Bates Machine Company, Joliet, 111., and
is now regularly used on all Bates Cor-
liss engines. With this inertia gear the
disengaging parts, instead of being forced
into and held in their path by springs,
rollers or other devices, travel in the de-
sired path by natural forces involved in
the movement.

Referring to Fig. 1, the dashpot arm
is of bell-crank form, one arm carry-
ing the dashpot rod and the other the
catch block. The dashpot arm is keyed
to the valve stem and a sleeve on its
inner side fits into a bored recess in the
steam bonnet, thereby gaining bearing
surface.

The steam arm has a liberal bearing
surface on the bonnet and is driven by

fVhat the in-
ventor and the manu -
facturer are doing to save
tjwe and money in the en-
0ne room and power'
house. Engine room
news

is controlled by the governor and car-
ries the knock-off cam and safety cam.
The operating movements are as fol-
lows: In opening the valve the valve
rod moves to the left, the latch shaft en-
gages with the block and continues in
this path until the knock-off bar comes
into contact with the knock-off cam and
is forced outward', raising the latch until
the block is released. The dashpot then
comes into action and returns the arm to
which the block is attached to the original

Inertia Corliss Valve Gear

the valve rod in the usual way. A sub-
stantial boss on the steam arm carries
the latch shaft on the inner end of which
is firmly mounted the knock-off "bar,
these two parts forming practically one
solid piece of steel. The knock-off ring

position. The follower pin is firmly fixed
to the steam arm and acts only in the
event of the dashpot failing to close the
valve.

The construction and balancing of the
latch shaft and its knock-off bar attach-

ment are such that the inertia due to
the reciprocating motion and the gravity
of the parts assures an automatic latching
action at the end of the return stroke
between the shaft and block without the
use of any spring or other mechanical
device, and in turn assists the unlatching
at the point of cutoff, thereby reducing
the reaction on the governor.

Cylinder ^ |^k_e

■l:-:i'.^-
-o ■•.•■.-„-.•

Fig. 2. Details of Dashpot

The depth of the latching and the
amount of clearance of the catch blocks
may be set with the greatest ease while
the engine is running at full speed and
is accomplished by the two adjusting
screws.

This valve gear has been thoroughly
tested and found to work positively and
quietly up to the limit speed of vacuum
dashpots, which is considerably over 250
revolutions per minute.

The dashpot now used on Bates Cor-
liss engines is also of special design and
is claimed to be remarkable for quick
action, noiseless operation and durability.
It is set beneath the soleplate. is made
without packing or leather, and the meth-
od of cushioning enables it to act over
the wide range of lifts without requiring
adjustment.

Referring to Fig. 2. the dash-
pot cylinder and plunger are of two diam-
eters with a ground fit on each. With
the plunger at its lowest postion, there
remains an annular internal chamber
which is full of air. An air passageway
is provided from the chamber to a point
underneath the plunger, and the area of
this passage may be varied by the needle
valve to regulate the amount of air trans-
ferred to the lower chamber.

September 26. 1911

POWER

499

In operation, the air is displaced from
the annular chamber to the vacuum cham-
ber below the plunger exactly in propor-
tion to the lift of the plunger, the air so
transformed forming the cushion. Thus
the cushioning effect is always propor-
tionate to its work and the air is driven
back and forth without noise within the
pot.

These improvements in valve gear and
dashpot afford positive operation of the
valves at slow speeds, but their import-
ance is greater as the speed increases.

Goulds Centrifugal Pumps

The Goulds Manufacturing Company,
Seneca Falls, N. Y., has just placed on
the market an entirely new and improved
line of centrifugal pumps. These pumps
are furnished in both the single-stage,
single-suction and single-stage, double-
suction types. Either type may be ar-
ranged for belt drive or direct connection
to electric motor, gas, gasolene or steam
engines, and steam and hydraulic tur-
bines. Both the single-suction and
double-suction pumps contain special fea-
tures. The impeller in the single-suction
pump is of the open type and is ma-
chined to minimize the clearances between
the impeller and the side covers; this
feature influences the high efficiency ob-
tained in this pump. The vanes are so
designed that maximum economy is had
under normal conditions.

Although of the single-suction type,
the impeller is so designed that end thrust
is eliminated.

The shaft stuffing box has a brass

on a horizontal joint. Dividing the cas-
ing permits quick and ready access to
the interior parts of the pump for in-
spection without disturbing the pipe con-
nections; this feature is illustrated here-
with. The impeller is of the modern in-
closed type and develops a high effi-
ciency under the conditions for which
the pump is designed. The bearings are of
the ring-oiling type, independent of the
stuffing boxes, and are provided with re-
movable shells lined with anti-friction
metal. The stuffing boxes are provided
with brass water-sealing rings.

The double-suction pumps are made
for heads up to 150 feet and the single-
suction pumps operate against maximum
heads of 100 feet.

"Sea" Rings Automatic Pis-
ton Packing

"Sea" Rings packing, recently purchased
by the H. 'V. Johns-Manville Company,
100 William street. New York City, is so

Construction of the Ring

Rotor of Goulds Centrifugal Pump

water-sealing ring which prevents air
from being drawn into the pump at this
point.

The single-stage, double-suciion cen-
trifueal pumps are designed with the cas-
ing made of two castings boiled together

constructed tiiai it hugs the piston rod,
during such times as high-steam pres-
sure is in contact with the stuffing box.

These rings are molded of laminated
asbestos, !l.i\ or duck in wedge form,
with their thin end turned inward. There

is a hollow space in every ring, between
the lip and the heel, as shown in Fig. 1,
into which the steam follows, so that the
steam itself and not the gland pressure
forces the rings against the rod.

Several rings are used in a stuffing
box, as shown in Fig. 2, but no one cup
leather takes the whole strain, as it is
divided among the three, four or more

/it — -it»li pmr

Fig. 2. Rings in Stuffing Box

rings, each taking its share in the work
of preventing leakage to the atmosphere.
It is claimed that these rings will
withstand 600 degrees Fahrenheit super-
heat. They work just as well on hori-
zontal as on vertical rods; and are for
use on pumps, steam hammers, air com-
pressors or for any other purpose.

New Diagrammeter

The accompanying illustrations show a
new device designed to measure steam-
engine diagrams. It is used with a scale
which is based upon a spring set at 50
pounds; the lines represent inches and
fractions of inches which when multiplied
by the weight of the spring will indi-
cate the mean effective pressure in
pounds.

A diagram with the instrument in a
position ready to commence tracing is

Fig. I.

Placing the Instrument on the
Diagrams

shown in Figs. J and 2. In Fig. 3 is
shown the scale employed.

When measuring a diagram the instru-
ment is placed as in Fig. 1. The fixed
point A over the diagram is placed over
one perpendicular and the adjustable
point fi is placed over the other perpen-
dicular of the area to be measured, and
is then secured in such adjusted posi-
tion. The fixed point A has a supple-
mentary point C. When in cither of the
positions shown in Figs. I or 2, one or

500

POWER

September 26, 1911

the other of these points forms a pivot
upon which the balance of the instrument
may be swung, such points being pro-
vided with a movable thumb-piece pivoted
to the bracket holding the points.

Mounted on the bar D is an adjustable
bracket E, carrying a sharp-edged roller
the periphery of which is in the same
plane as the point C. This adjustable

Fir,. 2. Ready to Jr.ace the Diacra.m

bracket is connected to the adjustable
point B by means of links and the ad-
justment of this point is by means of
the member £, the latter being provided
with a setscrew to hold it in the ad-
justed position. The bracket F may be
set at any position on the bar D to ac-
commodate the size of the diagrams to
be measured.

Fig. 3. Scale Used with Instru.ment

The instrument is used as fol-
lows: It is first employed in the
position shown in Fig. 1 in measuring the
distance between the perpendiculars of
the diagram. The instrument is then re-
versed and placed in the position shown
in Fig. 2, with the point C at the junc-

tion of the base of the diagrams and a
line X drawn through the center of these
diagrams, the wheel being placed di-
rectly on the line. The point C is then
traced around the boundary lines of one
of the diagrams in the direction of the
toe. When the tracing of the boundary
line has been finished the instrument will
rest at an angle to the base line of the
diagrams and the center line X, and when
in this position the marking point or pin
H is depressed, making a perforation
in the paper. The distance from
this mark to the center line of the
diagram is the mean hight of this dia-
gram, and if such distance be measured
off on the scale shown in Fig. 3 the mean
effective pressure of steam in pounds
may be determined. The opposite dia-
gram on the card will be measured in
precisely the same manner, and by this
means the mean effective pressure of
steam for each stroke of the piston may
be readily determined.

This device is the invention of Rudolph
Schierbeck, 2620 Master street, Phila-
delphia. Penn.

Sharood's Automatic Injector
Vahe

This device is designed to act as a
check valve in automatically preventing
the escape of vapor or steam and to al-

Fic. 1. Exterior of Valve Body

low the passage of liquid as it accumu-
lates.

Water in passing through the valve

rriB

casing maintains a high velocity, creating
a vacuum in the pipe to which the valve
is attached, and thus rapidly relieving
the pipe of condensed water.

In Fig. I is shown a longitudinal sec-
tional view of the valve, both ends being
threaded for connecting to a pipe line.
In Fig. 2 is shown a sectional view of
the valve as connected to a pipe. In this
view /4 is a common pipe tee with a plug
B on top and C is a union connection.
The cones or jets E, F and G are also
shown as located in the valve. The strainer
D keeps the valve free from dirt or sedi-
ment. The inlet of the valve is at the
right and the water and steam find an
outlet through the valve H at the end of
the valve body.

In the valve are arranged a series of
cones so placed that a space is left be-
tween the outer face of one and the
inner face of the ajacent cone. This ar-
rangement forms a space around the
small end of the two cones. The large
ends of these cones fit the inside of the
pipe and are secured by means of threaded
ends and are made tight by means of
packing rings. The general arrangement
is evident in the sectional view.

Under normal conditions steam will
till the pipe and will be projected through
the several cones against the check valve
H. Steam, it is said, does not open the
check valve, but when the steam con-
denses water fills the pipe and will
pass out through the cones. The force
of the water will open the check valve
and the water will escape through it.

When the valve is to be used with
high-pressure steam a disk containing
three small openings is inserted in the
orifice L, thus reducing the orifice and
preventing the high-pressure steam from
opening the check valve.

This valve is the invention of S. V.
Sharood. 263 North Main street. Brock-
ton, Mass.

Fic. 2. Details of Valve

September 26. 191 1

POWER

501

National Convention
N. A. S. E.

The twenty-ninth annual convention of
the National Association of Stationary
Engineers was called to order at the Music
hall in Cincinnati at ten o'clock on Tues-
day morning, September 12, by John A.
Kerley, chairman of the local committee.
After an invocation the convention was
welcomed to Ohio by Attorney-General
Timothy S. Hogan on behalf of Governor
Harmon, who was in the East. Mr.
I Hogan pictured the developments of the
I past century and pointed out the im-
: portant part which the engineer had
; played in them. A century ago Wash-
ington was further from Boston than it
is from Japan today. How grateful one
should be for the conscientiousness and
I devotion of the man at the throttle, the
man who ie behind the industries of
America, the greatest industries of the
world.

Mayor Louis Schwab welcomed the
convention to the city in an address which
showed an understanding of the aims, ob-
jects and methods of the association quite
unusual in the public official. He gave
much of the credit for the progress of
recent years in steam engineering and in
the conservation of the fuel supply to
the organization then in convention.

President Carl S. Pearse responded
fitly to the addresses of welcome. He
reviewed briefly the development of the
section in which the convention was held,
the beneficial things which the general
government is doing for the people and
expressed the belief that it is only be-
cause we are new at lobbying and apt to
neglect the duties which we owe to our
profession that some of these govern-
mental activities are not exercised in our
behalf.

Walter Draper, president of the Cham-
ber of Commerce, followed with a review
of the accomplishments and the hopes of
Cincinnati. He paid a tribute to the
bravery of the engineer of the Chamber
of Commerce, who stuck to his post in
the basement of the burning building and
kept the elevators running until every-
body was safely out.

Vice-president Edward H. Kearney,
responding to Mr. Draper's remarks,
pointed out the opportunities of the real
engineer and showed how he had de-
veloped from a small to an important
factor in the industrial scale and from
a workman had become a man of affairs.
Charles S. Wirmel, State labor com-
missioner, was the nevt speaker. It is
rumored, by the way, that he is slated for
the chief examinership of engineers. He
has often attended these conventions as
« delegate. He spoke interestingly and
undersfandlngly of the work of the as-
sociation and gave statisiirs regarding
the industries of Ohio and the condition
of labor therein. There are 16,000
licensed engineers In the State.

Past President William J. Reynolds
responded to the commissioner in a brief,
witty sally which brought the introductory
exercises to an end.

The president's address, presented in
the afternoon, dealt with the apathy of
the State deputies and local secretaries
and expressed approval of recommenda-
tions by deputies for the removal of
secretaries who do not attend to their
duties. He approved the work done by
the State associations and recommended
submission of the dates proposed for
State conventions to the national presi-
dent for approval in order to facilitate
the attendance of national officers and
representatives of the official organ. He
recommended the employment of an
educator "to act as a bureau of informa-
tion and to assist local associations in
educational work"; also, the adoption of
a uniform log or daily report for plants.
He urged the importance of continued
effort for license legislation, but pointed
out that each bill must be submitted to
the license committee of tne national
association for approval before the as-
sociation can lend it financial or moral
support. He reviewed at length the pro-
ceedings leading to the suit filed against
the association by the former publishers
of the National Engineer and approved
the social activities which have done so
much to advertise the association and
hold the members together.

The report of the secretary showed
the receipts of the year to amount to
nearly Sol, 000, about half of which was
profits upon the National Engineer. During
the past year there have been organized
11 new associations, while 13 of the old
have surrendered their charters, 2 of
these on account of consolidating with
other locals. There have been 1626 mem-
bers initiated, 1290 dropped out and 31
were expelled. Per capita tax has been
paid on 18,402 members, but the total
membership, including 821 honorary and
associate members, is 20,167. New York
State leads the list with 2574, with Ohio
a close second at 2461.

The report of the treasurer shows that
the total disbursements for the past year
have been .^22,515, of which S12,632 was
for mileage to the Rochester convention.
A resolution providing for an organizer
at S2000 a year and expenses was voted
down.

On Thursday morning the real work
of the convention commenced with the
report of the credential committee seating
378 delegates.

The educational committee had of-
fered prizes of SlOO, S.SO, S25, and three
of SIO each to the associations sending
in the best set of answers to a series of
questions submitted, and recommended
that the first and second prizes be divided
between Denver No. 1 and Lowell No.
17, which tied with 716..'^ points out of
a possible 720. Hamilton No. 4, of
Ohio, won the third with 689.3; Omaha

No. I, the fourth with 678.9; Butte City
No. I, the fifth with 666.5; and Newark,
N. Y., the sixth with 661.4. A gold-
plated Lippincott indicator, donated by
A. C. Lippincott for award to the author
of the best essay on "The Utility of the
Steam Engine Indicator as an Essential
in a Steam Plant," was given to E. J.
Rose, of Detroit No. 1. A Horn planim-
eter, presented by E. B. Skinner, of the
Skinner Engine Company, to be given to
the author of the best essay on "The Iso-
lated Steam Plant vs. The Central Power
Plant," was awarded to A. W. Miller, of
the same association. There were, how-
ever, but two contestants for the last
prize and these were both Detroit men.
The committee says, with regard to
the general contests, "From the small
percentage of replies it would appear
that the vast majority of the associations
either have not the time or inclination to
give to progressive work serious atten-
tion."

The license committee acknowledged
its inability to secure during the past
year sufficient data to compile a satis-
factory publication of license and boiler-
inspection laws now in force, and recom-
mended that some method be sought
whereby the committee may render as-
sistance to State committees without wait-
ing for the approval of their bills by the
national committee and president, as this
is usually prohibitive on account of time.
Proposals to appropriate .S5000 for
educational and license work, and to re-
duce the per capita tax from 75 to 60
cents, were defeated.

The national secretary read the roll
of members who had died during the
year, and a quartet with organ accom-
paniment rendered several appropriate
selections.

The mileage for the present convention
was found to amount to SI 1,976.

It was decided to hold the next con-
vention in Kansas City.

The officers elected for the ensuing
year are: President, Edward Kearney, of
Boston; vice-president, John F. McGrath,
of Chicago ;-secretary, Fred W. Raven, of
Chicago; treasurer, S. B. Forse, of Pitts-
burg; conductor, Fred L. Ray, of Louis-
ville; doorkeeper, Anthony Deutsch, of
Cincinnati; trustee, George Brownhill, of
New York. The president appointed
Joseph Carney, of . New York, as
trustee in place of J. H. Van Arsdale,
of St. Louis, resigned.

The social program commenced with
an informal reception at the Sinton on
Monday evening, at which an opportunity
was afforded for the older delegates to
enjoy a reunion and for the newcomers
to get acquainted. On Tuesday even-
ing. The Goldenburg School, presented- an
original musical play, "A Royal Mas-
querader." the book of which was written
by Grace Delaney Goldenburg, daughter
of past national treasurer Dan Delaney,
and the music by her husband, William

502

POWER

September 26, 1911

Smith Goldenburg. The large stage of
Music hall was effectively filled by a
company and chorus aggregating some
150 persons and the light and catchy
music and witty lyrics made a decided
hit.

On Wednesday the visitors were the
guests of the Lunkenheimer Company,
which had chartered the steamer "Island
Queen," in which the party to the num-
ber of nearly 3000 were conveyed down
the river to the Fernbank dam, and then
back past Cincinnati to Coney island,
where a barbecue with burgoo and ice
cream accompaniments was served. Danc-
ing, bowling, the annual baseball game
between the engineers and supplymen,
races, games, a band concert, etc., made
a pleasant afternoon and the party was
returned to the city on schedule time.
The hosts had anticipated every possible
wish and need of their guests, even to
providing hospital attendants and facili-
ties in case of accident, but the day
passed off without a single mishap and
their unobtrusive concern for everybody's
comfort and amusement brought to the
managers of the Lunkenheimer Company
the satisfaction of a thoroughly happy
and contented party and many warm ex-
pressions of appreciation.

On Thursday evening there was an-
other entertainment at the Music hall
at which local and visiting talent united in
a successful vaudeville program. A grand
ball at the Sinton concluded the week's
amusement.

The exhibition held in connection with
the convention under the auspices of the
National Exhibitors' Association was the
largest and best in the career of the as-
sociation. The Music hall, in one wing
of which the exhibition was installed,
stands upon historic ground from an ex-
hibition standpoint. Here in a building
erected for a sangerbund was held, about
the middle of the last century, the first
industrial exhibition in this country.
These exhibitions were continued until
interrupted by the Civil War and resumed
in 1871. In 1875 an interesting series
of engine tests was conducted at one
of these exhibitions by John W. Hill,
C. E., and others. Mr. Hill and several
of the participants in these older ex-
positions were present. The large hall
was divided into a series of booths uni-
form in arrangement and decoration,
lighted with large electric globes and with
an effective color scheme. The delegates
spent much of their time among the ex-
hibits, and there was a large attendance
of local engineers.

In the Life and Accident Association,
Past National President James G. Beck-
erley was reelected chairman of the board
of trustees; J. D. Taylor, secretary-
treasurer, and John M. Lynch, trustee.
The salary of the secretary-treasurer was
fixed at SI200 for the coining year.

The officers elected by the National
Exhibitors' Association for the ensuing

year are: President, H. H. Ashton, of
Boston; vice-president, M. B. Skinner,
of Chicago; secretary. Homer Whelpley,
of Cleveland; treasurer, William T. John-
son, of Buffalo; executive committee,
Louis B. Mann, of New York; H. A.
Pastre, of Pittsburg; J. W. Peterson, of
New York; Harry Raymond, of Boston;

F. E. Sly, of Milwaukee.
Resolutions of sympathy were passed

and sent to the family of Edward Mc-
Carthy, whose death occurred on August
18 last. Mr. McCarthy was a representa-
tive of the George W. Lord Company, of
Philadelphia, and had attended many of
the National Association of Stationary
Engineer meetings in the interest of the
company.

Carl S. Pearse, the retiring national
president, was presented with a handsome
diamond ring, William D. Purcell, the re-
tiring president of the Exhibitors' As-
sociation, with a gold watch and chain.
The Exhibitors' Association presented
John A. Kerley, chairman of the local
committee, with a handsome stickpin.

The winners of the four prizes offered
by the Ashcroft Manufacturing Company,
of Cincinnati, 0., were; First prize.
Tabor steam- and gas-engine indicator,

G. W. Boothe, of Ironton, O.; second
prize, Ashcroft averaging planimeter, J. A.
Murray, Denver, Colo.; third prize. Coffin
averaging planimeter, C. Williams, Provi-
dence, R. I.; fourth prize, Ashcroft com-
bination valve grinder, L. A. Henderson,
Clinton, la.

C. M. Schneider, by a score of 208,
won the bowling trophy offered by the
Supplymen's Association for the highest
score in the bowling contest, and for the
first time the Supplymen won the base-
ball game.

The following firms and companies
were represented:

.Albany Lubricating Company, Allis-
Chalmers Company, American Fabric
Belting Company, Huhn Metallic Packing
Company, American Radiator Company,
American Ship Windlass Company,
American Steam Pump Company, Ameri-
can Steam Gauge and Valve Manufactur-
ing Company, Anchor Packing Company,
V. D. Anderson & Co., Arctic Ice Ma-
chine Company, Armstrong Manufactur-
ing Company, Arrow Boiler Compound
Company, Ashton Valve Company, Atlas
Rubber and Belting Company, Bird-
Archer Company, Bishop-Babcock-Becker
Company. Black Diamond Company, S. F.
Bowser & Co., Builders' Iron Foundry
Company, Burr-Oak Belting Company,
A. W. Cadman Manufacturing Company,
Cancos Manufacturing Company, The
Philip Carey Manufacturing Company,
Chapman Valve Company, A. W. Chester-
ton Company, Clement Restein Company,
Cling-Surface Company, Crandall Pack-
ing Company, Crane Company, Creac-
head Manufacturing Company, Crocker-
Wheeler Company, Dearborn Drug and
Chemical Works, Desmond-Stephan Com-

pany, Diamond Power Specialty Com-
pany, Eagle Oil and Supply Company,
Eagle White Lead Company, Evans,
Almirall & Co., Evans Oil Works, Fair-
banks Company, Federal Metallic Pack-
ing Company, Ferguson Publishing Com-
pany, Fisher Governor Company, Frank-
lin Oil Filter Company, France Pack-
ing Company, Garlock Packing Company,
Greene, Tweed & Co., Gutta-Percha
Rubber and Manufacturing Company.
Hartford Steam Boiler, Inspection and
Insurance Company, Hawkeye Com-
pound Company, Hawks Boiler Com-
pany, Hill & Griffith Company, Hills-
McCanna Company, Hill Pump Valve
Company. Home Rubber Company,
Hoover-Owens-Rentschler Company, In-
ternational Acheson Graphite Company,
International Text Book Company, Jen-
kins Brothers. Joseph Dixon Crucible
Company, Kent Lubricating Company,
Keystone Lubricating Company, Knopf
& Johnson Company, F. & F. Koenig-
kramer, Lagonda Manufacturing Com-
pany, Laidlaw-Dunn-Gordon Company, P.
D. Lawrence Electric Company, A.
Leschen & Sons Rope Company, Liberty
AlanufacturingCompany, Elliott Company,
George W. Lord Company, The Lun-
kenheimer Company, Lytton Manufactur-
ing Corporation, McCord Manufacturing
Company, James McCrea & Co.. Mc-
Donough Automatic Regulator Company,
McLeod & Henry Company, W. B. Mc-
Vickar Company, Manning, Maxwell &
Moore, Marion Machine, Foundry and
Supply Company, Mason Regulator Com-
pany, Mechanical Rubber Company,
Michigan Lubricator Company, Mining
World, Mineral Products Company,
Charles H. Moore Oil Company, Murdock
Manufacturing and Supply Company, Na-
tional Engineer, National Tube Company,
New Era Manufacturing Company, George
M. Newhall Engineering Company, New
York Belting and Packing Company, New
York and New Jersey Lubricant Com-
pany, The F. W. Niebling Company.

F. A. Nusbaum Company, Ohio Blower
Company. Ohio Grease Lubricant Com-
pany, Osborne High Pressure Valve Com-
pany, Otis Elevator Company, Peerless
Rubber Manufacturing Company, Penn-
sylvania Oil and Supply Company,
The Perolin Company of America.
Peterson Engineering Company, Phila-
delphia Grease Manufacturing Company,
Pittsburg Gauge and Supply Company,
The William Powell Company, Power,
Practical Engineer, Quaker City Rubber
Company, Revere Rubber Company.
Richardson-Phenix Company, Ridgway
Dynamo and Engine Company. River-
side Metal Refining Company, John
A. Roebling & Sons, Safety Equipment
Manufacturing Company, Scandinavia
Belting Company, Schaeffer & Budenberg
Manufacturing Company, S. C. Regu-
lator Company, W. H. Simmons & Co.,

G. L. Simonds & Co.. Southern Engi-
neer, The C. E. Squires Company, Stand-

September 26, 1911

ard Oil Company, L. Steigert & Co.,
Strong, Carlisle & Hammond Company,
Terry Steam Turbine Company. Thermoid
Rubber Company, Toledo Pipe Thread-
ing Machine Company, Trill Indicator
Comipany, Triumph Electric Company,
Under-Feed Stoker Company of America,
; Universal Lubricating Company, United
I States Graphite Company, The Vanda
I Company, Henry Vogt Machine Com-
I pany, R. G. Von Kokeritz & Co., War-
I ran Webster & Co., Westinghouse Air
I Brake Company, Westinghouse Machine
' Company, Wickes Boiler Works, Willcox
Engineering Company, The D. T. Wil-
' liams Company, Williams Gauge Com-
' pany.

Ohio N. A. S. E.
Convention

State

The Ohio State Association of the Na-
tional Association of Stationary Engi-
neers held its convention at Cincinnati
on the day preceding the national con-
vention. The sessions were held in the
Sinton hotel, where John A. Kerley, chair-
man of the local committee, conducted
the introductory exercises.

After an invocation, Scott Small, di-
rector of public safety, welcomed the
convention to the city in behalf of Mayor
Schwab and was responded to by Presi-
dent Eichhorn. National President Pearse
then said a few words and the conven-
tion went into regular session with 37
delegates qualifled.

The secretary reported that there were
41 associations in the State association
on June 1, 1910; that one had been ad-
mitted since, two had withdrawn, and
two dropped from the rolls. There was
a net increase in membership of 157.
Much of the time was devoted to the dis-
cussion of legislative and educational
methods and a resolution submitted by
the Kentucky State Association favoring
the expenditure by the national associa-
tion of SvSOOO per year for educational
work and in behalf of State license laws
was indorsed.

The officers for the ensuing year will
be John J. Coughlin. of Hamilton, presi-
dent; Thomas F. Synnett, of Oayton,
vice-president; Joseph J. Ahlers, of Cin-
cinnati, secretary; John E. Radlgan, of
Cleveland, treasurer; Casper Geise, of
Delphos, conductor; T. J. Kolb, of Mid-
dletown, doorkeeper; T. E. McFadden,
of Cleveland, State deputy.

The retiring president was presented
with a past president's jewel, and votes
of thanks were tendered to Governor Har-
mon and Chief Inspector W. E. Haswell
for their support of the boiler-inspector
law and to the mayor, press. Personal
Liberty League and the local committee
for attentions bestowed. Lima was se-
lected as the next place of meeting by
one vote. Toledo tying nn the first
ballot.

POWER

Evening Technical Courses at
Pratt Institute

Practical evening courses for young
men employed during the day will be
conducted, commencing September 27 and
concluding March 22, by the School of
Science and Technology, of Pratt In-
stitute. The classes will meet on Mon-
day, Wednesday and Friday of each week
at 7:30 p.m.

The courses will include practical
mathematics, technical chemistry, in-
dustrial and elementary electricity,
mechanics, electrical machinery, electrical
design, machine design, mechanical draw-
ing, mechanism, steam and steam en-
gines and strength of materials.

Full information regarding these
courses may be had by writing to the di-
rector of the School of Science and Tech-
nology, Pratt Institute, Brooklyn. N. Y.

PERSONAL

Manning E. Rupp, formerly on the
Panama canal work, has accepted a posi-
tion as mechanical engineer with Stanley
G. Flagg & Co., of Philadelphia.

503

Cliet Richland for butter, his sloivs to in-
crease :

The one wanted grease fof to inn Ihe "ma-
chine."

And the other some butter for his cuisine.

The grease did not come: llie cliief made a
liicli:

To run without grease would raise tlie Old
Nick.

Harry H. Atkinson, proprietor of the
Economy Lubricating Company, of Bos-
ton, Mass., sailed on September 19 from
New York for an extended tour of Europe
in the interests of the company.

"We sent It, you got It : look 'round in the

store."
Wrote the makers. XJp rose the chief with a

roar :

' .\vast 1 ye tiremen, deckliauds and oilers.
Search all the ship, from the decks to the

boilers.
If the tub is on the 'Asliury Park.'
I swear I'll have it it we hunt till dark :"

While in the kitchen an oiler judicious
Found in the Icebox a tub most suspicious.
Said the garrulous cook : "Wot's aJI this 'ei*e

fuss?"
"Why." howled the oiler. "Ihis stuff lyiongs

to us !

W. E. Haswell, who has been the chief
examiner of engineers and chief of boiler
inspection in Ohio, has been appointed
secretary of the Ohio Board of Adminis-
tration. This is a consolidation of the
administrations of nine important State
institutions. It is said that Charles H.
Wirmel, at present labor commissioner,
and one of the first examiners to be ap-
pointed upon the passage of the license
law, is slated for the position which Mr.
Haswell is leaving.

How the Luhricant Made

Ciootl

By H. E. Hopkins

Ilils is a yarn from Ihe "Asbiiry I'ark"
In which Ihe proceedings are somewhat dark.
"Iwonld be hard to prove its veracity,
liiil Ibis Is the way II was spun lo me.

This iTiifl piles the waters of New York bay.
And carries for passengers each week ilny
The men who own railroads and bonds and

shared —
Kings of nnance and large business alTalrs.

mily ttlchmond. sir. was Ihe clilrf engineer,
Itelnved bv his men. to Ihe pARaengers dear:
And the' bead chefs name was e<inally

rliylbmlc.
nilly lllchland was bis patronymic.

"Itllly" did answer for elihers flrsl name —
It was from the last ones disaster came
To Ihe engine-room crew 'nealh the proud

ship's deck.
And Ironlile there was for a lime, by heck !

f'blef Ulcbmond bad sent lo the makers' for
grease.

"This Is not butther. 'tis the grease. If ye

plaze ;
(11 s'pose ye've used ut in all the ongtrays.
If ut made good cookin', ye've done yerself

proud.
Take it from me. Mister I'athrick O'Dowd I"

And thus it turned out that the chief's grease

was sent,
Rut. alas and alack ! 'twas welinigh spent.
'Twas used, it Is said. In soup, salad and

roast
.\nd also to "butter" the passengers' toast.

It certainly had a proper consistence
To be put wllhin Ihe pifTc tir r/nin1ancc :
Tliat grease »ii(«t i>e good which will serve

;he mc'nn
And keep the maehlnery running loo !

So here's to both mils: may their luck In-
crease.

And we hope In fnlnre each gets his own
"grease."

They've llckled nornr palates with this kind
of "lie."

And here we will leave Ibeni with handshake
and smile

POWER

September 26. 1911

$ i> r-, ?; .«

That our advertisers
are telling the truth in
their advertisements is
really not such a new
thing.

Read this letter which
we received last year from Mr. E. J.
Kearney, of Kearney & Trecker Com-
pany, regarding his advertising in one
of our papers:
Hill Publishlmg Company,

New York.
Gentlemen :

Under separate cover, we are sending you
nine half-page and five full-page proofs pre-
pared for the AiMEKiCAN Machinist. On three
of the full-page advertisements we have sub-
stituted in place of "vibration is eliminated"
"vibration is reduced to the minimum."

Your Mr. Britton gave the writer a little
talk on the advisability of making conserva-
tive and true statements in advertising. We
would, therefore, wish to avoid making a
statement of this kind in connection with
our product, although we have great confi-
dence in its rigidity.

Some 1 5 or 20 years ago there was published
in all of the Technical Papers a description
of a mammoth steam hammer, made for, and
probably by, the Bethlehem Steel Co., of
Bethlehem, Pa. This was the largest and last
of its kind, and one description of it stated
that when it struck a blow on an armour
plate, considerable vibration was set up in
the Allegheny IMountains. You will, there-
fore, see how impossible it is to say vibration
is absolutely eliminated from any machine
tool.

Yours very trulv,

Kearney & Trecker Co.

Milwaukee, Wis.

ri

It is significant as the
honest attitude of mod-
ern advertisers.

Truth in advertising
loses nothing, but gains
much, by being correctly
printed. It's the only way that pays.

Nowadays, manufacturers cannot af-
ford to get business any way except by
giving full value for the money.

Advertising serves its main purpose in
distributing information, creating con-
fidence and getting people started to
buying.

If you are not satisfied with what you
buy, you will not be caught again.

The business which is conducted on
the basis of a hope for permanency
must give value received, or it will die.

That's why only reliable products can
be continuously advertised.

Good advertising is the worst enemy
of graft, the foe of trickery salesman-
ship, the conqueror of unfair competi-
tion, the promoter of right dealing.

Our readers are more and more real-
izing this.

We intend to retain this faith by con-
tinuing our policy of keeping our ad-
vertising columns reliable and clean.

To buy from them is a guarantee of
satisfaction.

Vol.

M;\\ ^ORK. OCTOBER

No 1.

JUST as the Old .Man was saying: •'Ves, Mc-
Clatchy, we have had our eyes on you for some
time. When we want facts about oiu- plant, we
have only to come to you and we get them; you know
your business; you are the best engineer we ever had;
you are industrious, faithful to your duties, ever ready
to do more than we pay you to do ; you do not grumble,
and we are satisfied with you; you deserve some sub-
stantial apjjreciation. Now, beginning next week, your
wages will be increased to — "

McClatchy woke up! His faithful Ansonia had
called the turn just when Mac dreamed that some
real appreciation was heading his way.

Old Noah Webster has a good many short, but
pointed, stories in his dictionan,-, and in one of them
he relates that a "dream is that which is presented
to the mind by the imaginative faculty; to have indefi-
nite thought or expression."

( hir thoughts arc far from indefinite and our facul-
ties keen these days when the alarm on our mental
clockwork wakes us up to the fact that, somehow, we
must increase our weekly
stipend if Johnny is to stay
in school, and Lizzie to be-
come a teacher, and Mamie
to keep on at the business
college

If we would better our
condition, we must look on
our work in the light of a
business problem ; we must
regard our skill, ex|)erience
and intelligence as purchas-
able commodities, and ask
the old man to pay us what
(lur services are worth to
him

Of course he will say: "Show me how I can profit
by such an investment and I will willingly put up the
money."

What Jock McClatchy only dreamed has come true
to many a live-wire engineer who tackled his job from
the business side and knew just uhat he was doing, and
why.

He was not backward in letting his superiors know
what he knew, either, and they were willing to pay him
good money for his services, because the company
made a profit by the transaction.

To successfully run a power plant these hustling
days, one must have business as well as mechanical
skill. In almost ever^' issue of this paper is told the
experience of men who say they never could have made
good if they had not conducted their plants according
to business princi])les.

Wake up! That the old plant has heretofore man-
aged to keep its head above the business waters without
strengthening the banks of the levee, is the best of
reasons for piling up new sacks of method, energy and
push.

Some fine day — perhaps
not so very far off, either —
something is going to burst
alongside the old standstill
plant, and the inrush will
engulf it.

Wake up! But wake up
to the fact that to win out
you must fight with every
bit of eneru'v that is in you.

Get into the front ranks
of the army of General
Hustle and hike for the top
of Success Hill.

^■^^

506

POWER

October 3, 191 i

Producing Power from the Sun's Rays

It has long been recognized that all
forms of energy owe their existence to
the sun, but the ways in which this solar
heat is converted into useful energy are
many and often complex. For instance,
the potential energy in coal may be
traced to the action of the sun upon
growing vegetation centuries ago. The
coal is burned in a furnace and through
its chemical union with the oxygen of
the air, the energy is liberated in the form
of heat which, in turn, converts the
water into steam capable of performing
useful work.

Again, through the action of the sun,
water is evaporated and lifted from lower
levels to be deposited at higher levels in
the form of rain. From these higher
levels the water descends and its energy
of flow is utilized in waterwheels for
performing useful work.

Still another familiar instance of the
indirect action of the sun's rays is the
wind, which is employed for propelling
ships and for driving windmills.

The direct utilization of the sun's rays
for producing useful work, however, has

By A. D. Blake

By ihe use of stationary
mirrors the sun's rays are
directed against a sheet-iron
vessel containing water.
This is changed into steam
(it atmospheric pressure,
jcliich is used in a low-pres-
sure condensing engine for
pumping water. The com-
mercial practicability of the
apparatus depends iipon
its performance in tropical
regions ivhere fuel is expen-
sive.

that, theoretically, the maximum heat ob-
tainable from the sun's rays at the

Fig. 1. Ge.neral View of Absorbers

equator is about 204 B.t.u. per square foot
of heat-absorbing surface. This would de-
crease with latitude north or south and
at Philadelphia would be only about 40
per cent, of the solar constant.

V/ith a heating surface perpendicular
to the sun's rays as high as 90 per cent.
of the theoretical heat may be obtained,
but such a heater requires an expensive
mechanism which will revolve it as the
angle of the sun's rays changes. In the
present case a stationary' heater of the
meridian type is used, and, although
about 70 per cent, of the solar constant
is the maximum obtainable, the construc-
tion is such as to render the cost com-
paratively small.

In actual tests at Philadelphia, obtained
by weighing the water and taking tem-
peratures, as high as 88 B.t.u. were ab-
sorbed per square foot of absorbing sur-
face. From the foregoing it would ap-
pear that close to 150 B.t.u. per square
foot of heating surface might be ex-
pected in the tropics. This would be
equivalent to an efficiency of about 70
per cent., which compares favorably with
that of an ordinary steam boiler.

The plant in its present development
consists of an absorber or low-pressure
boiler, a low-pressure steam engine, a
condenser and auxiliaries.

The absorber, as shown in Fig. I, is
made up of a number of units each
consisting essentially of a rectangular
chamber for water and steam, inclined at
an angle with the horizontal, and two
flat mirrors for reflecting and concen-
trating the sun's rays. The steam and
water chamber, which is of sheet iron
painted black to absorb the heat, is set
on a flat wooden box covered with two
layers of glass with a 1-inch air space
between, and a 2-inch layer of granulated
cork on the under side. This is to pre-
vent conduction and convection of heat

teen tried from time to time and, al-
though proving feasible, heretofore has
not been commercially successful. In
most cases the cost of the necessary ap-
paratus has been so great, in proportion
to power developed, as to make suc-
cessful competition with other methods
of producing power impossible.

The most recent sun-power develop-
ment is that invented by Frank Shuman,
of Tacony, Philadelphia, who now has a
plant erected at that place for testing pur-
poses. Early in his investigations Mr.
Shuman recognized that to obtain the
maximum power from the sun's rays
would necessitate apparatus of such com-
plexity as to render the cost prohibitive.
He therefore decided to sacrifice efficiency
for cost and designed a plant which would
operate at a mean between the two.

It has been calculated by scientists

Fig. 2. Engine and Pumps

October 3, 1911

POWER

507

away from the absorber. It is obvious
that the greater part of the heat utilized
from the sun is radiant heat.

The boxes are mounted in fra.Ties and
are arranged on a quadrant so that their
angle with the horizontal may be altered.
These adjustments are made once a week.

The feed water is led into the bottom
of the water chambers and steam is
taken from the top and conducted to an
8-inch main. All the absorbers are con-
nected in multiple as regards both the
steam and feed-'"ater lines, and a con-
nection between the two permits any con-
densation in the steam to drain back into
the feed water. The individual connec-
tions to each absorber are lead pipe in
order to afford flexibility when adjusting
the angle of the frames. All the piping
is insulated with hair-felt covering.

The entire system is closed and a back-
pressure valve blows off when the pres-
sure rises above atmosphere. While the
temperatures attainable in the absorber
are such that pressures much higher

An ordinary surface condenser is em-
ployed and vacuums up to 28 inches have
been obtained. The air pump and the
circulating pump are belted to the main
tngine and for starting up the air pump
is thrown onto a small gasolene engine;
this arrangement, however, is only tem-
porary.

The condensed steam after leaving the
condenser passes through a separator,
then to a settling tank which removes any
entrained oil. However, should any oil
clog up the small space between the
plates of the absorber, these plates may
be easily removed and cleaned.

The engine at present is connected
through a chain drive to a reciprocating
pump which delivers water to a stand-
pipe against a head of 33 feet.

From actual tests made at Philadelphia
in August, 1911, it is reported that from
the absorber of 26 banks of units, each
containing 22 single units and having a
light absorptive area of 10,296 square
feet and an actual area of 5148 square

steam- or gas-engine plants except in
tropical regions where fuel is expensive.
In fact, these are the conditions which
the device is designed to meet and no
claims are made outside of this field.

It is stated that the plant now operating
at Tacony is soon to be taken down and
shipped to Egypt, where it will be erected
for irrigation work. It will then be work-
ing under the conditions for which it was
designed and its commercial value will
then be put to test.

All EmtTij;encv Pump Arrano;e-
iiient

The service pump which handles the
feed water in a certain power plant ob-
tains water from a river, but it can be
cut out entirely and city water used if
necessary.

.As the pump is used continuously day
and night it sometimes fails to furnish
sufficient water. It also happens that
occasionally the city-water supply is shut
off. Should it happen that both the city
supply and the pump fail at the same
time the plant would be forced to shut
down.

To prevent this, the chief engineer ran
a connection from the top of the air
chamber A, placed on one end of the
suction pipe of the pump, to the suction
pipe of the condenser, as shown in the
accompanying illustration. In case the
pump packing wears and fails to supply
sufficient water, a valve in the connection
between the air chamber and the vacuum

Disciharge fp Heater

1 To Pond

A><RANr,r.:ViENT OF Pump Piping

than atmosphere might be employed, such
pressures would have required stronger
construction which, in turn, would have
made the cost much higher and rendered
the device commercially impracticable. It
has been found that the pressure can be
regulated to a large extent by the level
of the water in the absorbers and this is
controlled by the feed pump.

The engine is of the single-cylinder
condensing type, 36x.^6 inches, running
at 150 revolutions per minute and es-
pecially designed for running on low-
pressure tteam. Separate inlet and ex-
haust ports are employed with large
port areas and the clearance is reduced
to a minimum, thus materially reducing
the cylinder condensation and permitting
the engine to be run with very little com-
pression.

feet of steaming surface, there was
developed during eight hours 4825 pounds
of steam, the amount per hour varying
with the time of day. The present plant
is rated at 100 horsepower based upon
tropical conditions, where not only is a
greater percentage of the solar constant
available but the temperature difference
between the outside air and the steam
is so much less as to reduce considerably
the condensation. The maximum indi-
cated power developed at Philadelphia
has been about ,1.3 horsepower when de-
livering approximately 3000 gallons of
water per minute.

The estimated cost of the entire plant
is .S20f) per horsepower. This, together
with the large area covered in proportion
to the small power developed, would
render competition impracticable with

pump is opened and the vacuum pump
forms a partial vacuum in the suction
pipe of the pump, thus drawing the water
in such quantities that the pump is en-
abled to force a sufficient supply of water
into the feed-water heater, from which it
is taken by the boiler- feed pump.

This arrangement has saved the plant
from three shutdowns since it was in-
stalled.

A small vertical boiler which was part
of an artcsian-wcll drilling outfit ex-
ploded the other day, killing a fanner
by the name of Jones, who was driv-
ing by at the time. At the coroner's
inquest a verdict was rendered placing
the entire responsibility for the accident
on the farmer, on the ground that he was
the only one killed.

POWER

October 3, 1911

Centrifugal Pump Capacity and Speed

Problems which often come up in prac-
tice and which seem to bother a great
many practical men. are how to make
calculations relating to the capacity and
speed of centrifugal pumps. In the de-
sign of centrifugal pumps there are so
many variables that it is impossible to
give formulas for capacity and speed that
would give accurate results for every
case. In fact, extremely accurate re-
sults are not necessary in work of this
kind as the capacity of a centrifugal
pump may be increased slightly by a
small change in speed without affecting
the efficiency of the pump to any ap-
preciable extent.

Capacitv

The size of a centrifugal pump is al-
ways designated by the diameter, in
inches of the discharge opening, and. as
a general rule, the pumps are so de-
signed that the velocity of flow through
the delivery opening is about 10 feet per
second. With this velocity of flow the
highest efficiency is usualh' obtained, but
some centrifugal pumps that are designed
for a velocity of flow of 10 feet per
second through the delivery opening are
capable of delivering water at a rate of
12 feet per second with but very little
change in efficiency. When calculating
the discharge of a centrifugal pump the
discharge velocity furnished by the build-
ers should be employed, but if this is
not known a velocity of 10 feet per sec-
ond should be used.

A simple approximate rule for calculat-
ing the discharge of a centrifugal pump
when the size of the delivery opening is
known is as follows:

Multiply the area of the delivery open-
ing in square inches by the velocity of
flow in feet per second and by 720 and
divide the product by 231. The result
will be the capacity in gallons per minute.

Expressing this rule as a formula.
i A V

0 =

(0

in which

(2 = Capacity of pump, in gallons

per minute;
A = Area of delivery opening, in

square inches;
K = Velocity of flow through de-
livery opening in feet per sec-
ond.
Example: What will be the discharge
of an 8-inch centrifugal pump?

Solution: Assume the velocity through
the delivery opening to be 10 feet per
second since it is not known. The area
of the delivery opening is

0.7854 X 8= = 50.265 square inches
Substituting in formula (1),

„ _ 720X50.265 X 10

Q — =,566

gallons f>rr vtitiulf
If the velocity through the delivery

By T. W. Holloway

C 'dh iihitions f^crtaiiiiiig
lo llic ( cipacity (uul speed of
renin J iigcil pumps, em-
bodying problems frequent-
ly met by the praetieal luaii.
Ill the soiiitioii of these, the
fundamental working for-
mulas eomnionly employed
III pump design are applied.

opening had been given as 12 feet per
second," the capacity of the pump would
have been about 1880 gallons per minute.

If the size of the pump is desired for
a given discharge, the diameter of the
delivery opening may be found by the
following rule:

Multiply the desired discharge by 231
and divide the product by the velocity of
flow in feet per second, by 720, and by
0.7854; then extract the square root of
thi's result.

Expressed as a formula,

^ = Nl <^:^xyio X V = °-^+

in which

D = Diameter of delivery opening in

inches;
Q and V have the same meaning as
in formula ( 1 I.
Example: .\ centrifugal pump is to
handle 5000 gallons of water per minute.
What size of pump should be installed?
Solution: .'\ssuming a velocity through
the delivery opening of 10 feet per sec-
ond and applying formula (2),

V

(-)

D:

: o.r,4

5000

,. = o.fi.

\ 10

64 X

14.;, uiiih s

14-inch pump would be

Probably
installed.

A 14-inch centrifugal pump was re-
cently installed to handle about 5000
gallons of water per minute under nor-
mal conditions, the capacity of the pump
having been calculated by formula ( 1 ).
After the pump was installed the dis-
charge was measured by means of a
rectangular weir, the nature of the basin
which received the discharge being such
that this could be easily done. The width
of the weir used was 42 inches, and
when the pump was operating under nor-
mal conditions the depth of the water
measured from the bottom of the weir
to the level of the water in the basin was
found to be 12 inches. A practical for-
mula for the discharge from a rectangular
weir was then applied. This formula
was as follows:

28S b y d=

is)

'.n which

Q = Quantity of water discharged, in

cubic feet per second;
& = Breadth of weir, in fee;;
d = Depth of weir, In feet.
Applying formula (3) to the case at
hand,

(? = 3.288 X .3 V I T^ = 1 1.5 culric jccl per
second
Since there are 7.48 gallons to the
c-:bic foot, the discharge in gallons per
r inute is

11.5 X 7.48 ;< 60 = 5161 gallons
This value is very close to the cal-
culated discharge when the velocity
through the delivery opening was taken
as 10 feet per second, showing that the
calculated discharge agreed fairly well
with the measured discharge. Of course,
both methods give approximate results,
but the comparison shows that the cal-
c'.'lated discharge, on t'^e assumption that
the velocity through the delivery opening
is 10 feet per second, agrees as well as
can be expected with what actually hap-
pens in practice.

Speed

The speed at which a centrifugal pump
should run will depend upon the design
of the runner and upon the head against
which the pump is required to work.
Theoretically, the circumferential speed
of the periphery of the runner, or. in
other words, the tangential or rim speed
of the runner, should be equal to the
velocity that a body would have after
having fallen through a distance equal to
the total head; that is, the static head
plus the head due to frictional resist-
ance.

The theoretical velocity of a falling
body is expressed by the formula

!< = 1 2 gh

in which

!• ^- Velocity, in feet, per second;
g = Acceleration due to gravity =

32.16;
h =z Might, in feet, through which
the body falls.
The velocity of the periphery of the
runner expressed in feet per minute then
becomes

V = Co X I 2 gh = 480 1 T
in which

V — Velocity in feet per minute.
Since h represents the total head, let h'
represent the static head and h" the head
due to friction. Then

h = h' -^ h"
Now. n' is known since it is the ver-
tical distance in feet between the water
level and the point of discharge and, ac-
cording to the laws governing the flow of
water in pipes.

i,=iM

2gd

October 3, 1911

POWER

509

in which

h" = Head, in feet, due to frictional
resistance;
f = Friction factor which is ordi-
narily taken as 0.02;
/—Length of pipe, in feet;
r, — Velocity of flow, in feet, per

second;
g =^ Acceleration due to gravity —

32.16;
d^ Diameter of pipe, in feet.
Substituting the value for h",

:/. +

2 ijd

and when substituting the value of h in
the formula for V the formula becomes

V = 480 ^

I' +

111
•g,l

(4)

This formula may be used for finding
the velocity of the periphery of the pump
runner, or, in other words, the tangential
or rim velocity of the runner. Having
found the velocity of the runner, the
number of revolutions per minute may
readily be found by dividing this velocity
by the circumference of the runner.

The results obtained by the method
just given for finding the speed at which
a centrifugal pump should run, should
be considered approximate as conditions
may be changed somewhat by the angle
which the tip of the vanes makes with a
tangent to the circumference of the run-
ner, and by the radial velocity of the
water issuing from the runner. An e.\-
a-nple will best show the method of ap-
plying the foregoing formulas for finding
the speed of a centrifugal pump.

Example: An 8-inch centrifugal pump
is discharging at the rate of 10 feet per
second through a pipe 300 feet long
against a head of 30 feet. If the diameter
of the pump runner is 24 inches, at what
speed should the pump be run?

Solution: Applying formula (4),
h- 30 feet;
f r 0.02 fool;
/ ^ 300 feet ;
I'. 10 feet per second;
p 32.16;
,/ = ,», = ij U, I .

Substituting,

,. 0 I 1 oo-' X M"' X (10)-

.^iBs jfrl p, r miiiuir

The circumference of &.c runner is

2 y 3.1416 6.28.32 feet

Therefore, the number of revolutions per

minute is

3185 -^ 6.2832 = 507,
or 500 approximately.

A general approximate rule which is
often used in practice for finding the
tangential velocity of the runner is to
multiply the theoretical velocity which a
body would attain in falling through a
distance equal to the static head by 1.25.
By this method the friction head does not
enter into the calculation, the friction
head being assumed to be 25 per cent.

of the static head, and is taken care of
by multiplying the theoretical velocity
due to the static head by the constant
1.25. Expressed as a formula,

1' = 1.J5 1 2 gli \

in which

1' =r Velocity, in feet, per second;
g = 32.16;

h = Static head, in feet, that is. the
distance in feet between the
supply and the point of dis-
charge.
The tangential velocity of the runner,
in feet per minute, is

r = 60 1' = (jo X I -'5 1 2 gli

from which

V = 600 1 h (s)

This general approximate formula
gives good results in most practical cases
where the discharge pipe is of usual
length, but if a very long discharge pipe
is used or if more accurate results are
to be obtained, it is usually better to take
the friction head into consideration as
was done in the first case instead of
using a constant, for all cases, to take
care of the friction head.

Applying this general approximate for-
mula (5 1 to the foregoing example,

V = 600 V 30 = 3286 jii'l per minute
which is the tangential velocity of the
runner.

The number of revolutions per minute
equals

3286 ^

2 X 31416"' ^"^

It will be seen that this result obtained
by the use of formula (51 differs only
slightly from the result found with for-
mula (4).

Although the exact capacity and speed
of a centrifugal pump cannot be definitely
determined by calculations, results which
are usually accurate enough for most
practical purposes can readily be obtained
by the formulas given.

E.vpcrientf with a Second
Hand Boiler
By William F. Joy

In a Southern city, some time ago, the
old "shot-gun" boiler which Jones was
operating, blew up and then Jones was
in the market for another boiler. He
accordingly went to a second-hand deal-
er and negotiated for a first-class, sec-
ond-hand boiler.

Now Jones had a friend named Allen,
representing an insurance company,
to whom he had fold his troubles. Allen's
advice was not to buy a second-hand
boiler, without having expert opinion on
it. He suggested that one of the in-
surance company's inspectors look over
the boiler before Jones purchased it, and
if it was found to be in good condition
the company would be glad to insure it.

"Oh, no!" said Jones. "Smith, the sec-
ond-hand dealer, and I went to school
together. I have every confidence in him;

I know he is on the level and he will
give me a square deal."

Later Jones thought better of the ad-
vice of his friend Allen and decided to
insure the boiler. When the inspector
visited the plant to examine it he found
it to be of an old type such as was used on
towboats a generation ago, with a fore-
and-aft steam drum. To get into the
boiler from the top, one first had to
enter the drum, then squeeze down
through the neck into the top of the
boiler itself. A number of braces on
both heads were broken, the tubes were
pitted and the sheets corroded, but the
outside of the shell was nicely adorned
with a thick coat of tar. Jones wondered
what good the tar did, but was told that
all second-hand boilers must be covered
with tar to preserve them.

When the inspector saw the tar he at
once became suspicious. He heated a
hrick and with the aid of a pair of tongs
began removing the tar. This showed
the shell to resemble a sieve. The boiler
was guaranteed by the dealer to be safe
for 1 10 pounds pressure. After calculating
the probable strength and considering its
condition, the inspector told Jones he
would allow 50 pounds and no more.

This decision annoyed Jones and caused
him to say, "If you don't want to insure
it. there are others, and I'll get a com-
pany that will." Accordingly an in-
spector from another company was called
in and was requested to examine the
boiler. A further application of the hot-
brick treatment disclosed more trouble,
making matters look still worse and add-
ing "insult to iniury"; so a third in-
spector was tried, hut with the same re-
sult.

Jones became angry when he realized
that no one wanted to insure his boiler;
so back he went to Smith.

"Say, Smith, I don't want that old boil-
er; no one will insure it. You will have
to take it back, and return my money."

Jones had paid part cash and given
his note for the balance. Of course.
Smith could not see it that way and re-
fused pomt-blank.

"That's a good boiler," said Smith,
"because Kelly says so, and he knows
more about boilers in a minute than those
inspector chaps know in a month."

"Well, I'll sue you," replied Jones.

"Go ahead and sue," said Smith; so
the controversy came to trial.

For reasons unknown to the uninitiated.
Jones lost his case and was compelled
to pay the costs of the suit, besides
losing the amount he paid for a bond,
to protect his note to the dealer, and as
Jones had already paid .S.SOO cash to
bind the sale, that went too, and he had
to make his note good for several huti-
dred dollars more. All he had left was
his first-class, second-hand boiler, and
that was useless.

Finally the boiler was relegated to the
scrap heap, and Jones bought a new
boiler.

510

POWER

October- 3, 1911

The Steam

The S. M. F. turbine, built by the
Sachsische Maschinen Fabrik, formerly
Richard Rartmann, in Chemnitz, is of the
pure multiple-stage impulse type, having
from 6 to 18 runners. The original type
of S. M. F. turbine, which is illustrated
in Fig. 1, had the runners divided into
three groups, there being two wheels in
the high-pressure, three in the middle,
and five in the low-pressure division. The
latest type brought out by the firm, of
which a front view is shown in Fig. 2,
has only two groups of runners, like the
Zoelly turbine, there being five wheels
in the high-pressure and six wheels in
the low-pressure division. The runners
are made of Siemens-Martin steel and
are forged in one piece with the hubs.
They are finished to a polish all over to
insure both quiet running and small
steam friction and are mounted from both
ends of the shaft toward the middle,
which is larger in diameter than the ends.
The dovetail blades are cut from pro-
filed nickel-steel bars and inserted
through two diametrically opposite open-

Turbine in Germany

F. E. Junge

By

Description of S. M. F.
kirbine, which is of pure
imptdse type. Latest de-
sign has eleven ivheels —
five in the high-pressure
and six in the low-pressure
division. Results of tests
to determine effect of shrouds
covering blade tips and the
effect of varying pitch of
blades.

Originally the runners had a blade
pitch of 0.55 and 0.66 inch respectively,
and no shrouding was employed. Later
the pitch was reduced to 0.39 and 0.47
inch respectively, and a shroud was
added. Still later, the shroud was
strengthened against the centrifugal force
by winding a layer of nickel-steel wire
around it. The shroud proper, which is

are packed by means of loose bushings, f
which are grooved after the manner of
the labyrinth packing. These bushings
are ground on the hubs, being pressed
by the steam pressure against a ground
and polished shoulder, which is provided
on the diaphragm. This arrangement
has the advantage that the bushings can
partake of and yield to small movements
of the shaft and hub, without harming
the packing. Owing to the fact that there
is no pressure difference between the
two sides of the runner and that the
expansion of the steam takes place in
the guide diaphragm only, the play be-
tween fixed and movable parts can be
kept amply large. Openings in the disks
serve to make the equalization of pres-
sure upon the two sides of the runners
complete.

At the passage from the high- to the
low-pressure part, in the latest construc-
tion, an especially long bushing with
labyrinth packing is employed. Besides
the purpose of packing, it serves as a
stop and shoulder while the shaft is
running through the critical speed. Live
steam is fed to the first guide diaphragm
through an annular channel which sur-

FiG. 1. Longitudinal Section of Original S

Turbine

ings of the wheel rim into the groove,
being held in place by distance pieces
in the ordinary manner. The long blades
of the low-pressure division decrease in
thickness toward the outer end, thus re-
ducing the centrifugal force and the
stress on the wheel disk. Their form
and manner of attachment are illustrated
in Fig. 3, which is very instructive as
showing the development of the wheel
and blade construction.

of U-section, is composed of three or
four segments, stiffens the blades, con-
fines the steam in a radial direction, and
reduces steam friction in the casing. The
wire layer serves to connect the blades
and shrouding into one rigid unit, and to
guard the system against blade fracture.
The guide wheels are made of
cast iron, and the guide blades of sheet
steel. Where the hubs of the runners
pass through the guide diaphragms they

rounds the casing. An overload valve
serves to admit live steam from this an-
nular channel directly to the third guide
diaphragm. In the latest construction
the turbine casing is divided in the hori-
zontal as well as in the vertical center
plane.

Both casing and bearings can move on
the foundation frame in the axial direc-
tion, thus allowing for variations in
length through heating and cooling. These

October 3, 1911

POWER

ill

variations are considerable, especially in
the high-pressure part, where tempera-
tures of 572 to 6S2 degrees Fahrenheit
occur. This precaution, as well as the
even distribution of material by proper
design, is necessarj' because, if neg-
lected, fractures are apt to occur when
high superheat is employed. The two
water-cooled main bearings are arranged

Fig. 2. High-pressure Side of 600-
HoRSKPO^ER S. jM. F. Turbine

separately from the casing, being mounted
directly on the frame. They are lubri-
cated by cooled oil under pressure, which
is supplied by a rotary pump. In addi-
tion, there is a hand pump for starting
and a steam-driven oil pump for reserve
purposes. The latter is automatically
switched in if the rotary pump gets out
of order.

To secure the exact position of the
turbine shaft in the axial direction and
to counteract the inconsiderable but un-
avoidable axial thrust, a collar thrust

adjusted to any speed limit. Usually it
acts when the number of revolutions of
the turbine surpasses the normal by 15
per cent. The oil-pressure regulator acts
by first switching in the reserve oil pump
when the oil pressure drops below a cer-
tain limit; and in case that the pressure

purposes of paralleling the generators is
accomplished either by a hydraulic rel.ay
from the switchboard or by means of a
handwheel provided on the turbine. Be-
tween the turbine and the generator an
elastic coupling is inserted, which com-
pensates the radial as well as the axial
inaccuracies of alinement of the two
units.

Special attention is devoted to the con-
struction of the stuffing boxes, which are
illustrated in Figs. 4 and 5, which show

Fic. 4. Stukfinc Box for High-pressure Sioe

drop should continue it throws the tur-
bine out of operation. The main steam
valve cannot be reopened by hand unless
the normal speed and the normal oil pres-
sure are restored.

Speed regulation is performed by
means of a spring governor, the action
being transmitted through a hydraulic
motor which acts on the throttle valve,
as shown in Fig. 2. \ combined ad-
justable-spring oil dashpot serves to
dampen any sudden fluctuations of the
governor. The throttle valve and the main
valve arc located in a common housing.

n

Pitch -OSS 0.66

J"'

the details of the packing on the high-
pressure side. Located at the inner end
of the packing is a bushing A, equipped
with labyrinth grooves. Adjoining it are
carbon rings consisting of three segments
which are lightly pressed around the
shaft by means of helical springs. The
packing in the axial direction is per-
formed by means of a number of small
spiral springs B, which are held in dis-
tance rings and transmit their pressure
to the carbon rings by means of wash-
ers. They also compensate for the ex-
pansion of the rings through heat and
permit a certain amount of sliding, ac-
cording to the condition of the
shaft. The circumferential helical springs

( — (~<M- r~ "4 —- — 7

Stog«;-S &-'0 1-5 n-,o 1-5 6-jO

Fig. 3. Development of Wheel and Blade CoNSTRt'CTioN

J::as> ^

Fig. 5. Details of Packing in High-
pressure Stuffing Box

bearing is provided on the nign-pressurc
side, but outside the main bearing. From
the prolongation of the shaft beyond the
thrust bearing, the safety governor and
the worm gear for operating the speed
governor are actuated. The latter runs
in an oil bath. The safety governor acts
by means of springs and levers on the
train steam-admission valve and can be

which is arranged either horizontally or
vertically beside the floor stand, the ar-
rangement depending upon the capacity
of the turbine. The balanced main valve
is combined with a bypass valve and is
opened cither hy a handwheel or lever.
The latter is used after sudden disen-
(■agement hy I'lc r.n'ety governor. Speed
variation within predetermined limits for

have lugs engaging projections and
recesses of the carbon rings, pre-
venting the latter from revolving v -th
the shaft. Bushing A and the three ..d-
joining carbon rings are inclosed in a
cast-iron casing which, at one end, is
surrounded by a bipariilc easing. The
latter has an annular space ('. in front of
which another stuffing box iv provided.

512

POWER

October 3. 1911

It consists of three more carbon rings,
which are pressed radially around the
shaft and axially against the packing
shoulder provided in the space E. If

300

Institute, of Charlotten'ourg. The pur-
pose of the tests was to ascertain, be-
sides the general economic efficiency, what
results attend the employment of shrouds
15

. -. i*eam Preisjre behind Governing Valv

Fig. 5. Results of First Series of Tests; Pitch 0.55

Imch: Blapes without Shrouds

necessary, packing steam can be admitted
through the tube D. A propeller ring,
seated on the shaft outside the packing
box, prevents the leakage of steam along
the shaft by aspirating air and pressing
it together with the steam into the water-
jealed drain pipe. The construction of
the low-pressure packing ring is sim-
ilar, with the difference that five carbon
rings are employed.

When the turbine is running at nor-
mal load the high-pressure stuffing
box has to pack against a pressure dif-
ference of five atmospheres within and
one atmosphere without, and the steam
entering the antechamber is conducted to
the low-pressure stuffing box in order to
guard it against the influx of air. In this
case the antechamber, by a valve-con-
trolled passage, is connected with the
space behind the fifth runner, in which at
normal loads a pressure slightly above
atmospheric prevails. If the waste steam
of the high-pressure stuffing box does
not suffice, the required packing steam
for the low-pressure side is taken from
the middle stage of the turbine. When
the carbon rings are new the stuffing box
is tight. When the rings are worn out
the influx of air into the turbine at pres-
sures below atmospheric, as when start-
ing, is prevented by using live steam
for packing purposes, as mentioned in a
previous paragraph.

A series of very interesting tests was
recently made with S. M. F. turbines by
Professor Josse, of the Royal Technical

or rings covering the blade tips in the
various stages, and what are the effects
on the efficiency of the turbine when
the blade pitch is reduced as described

tween the amount of the latter and the
density of the steam. A short summary
of the results of these tests follows:

In the first series of tests no shrouds
were employed, but a blade pitch of 0.55
and 0.66 inch respectively, was employed.
In the second series shrouds were used
and the blade pitch was reduced to 0.39
and 0.47 inch respectively. Otherwise
the conditions of the two tests were, if
not identical, yet sufficiently similar to
make a comparison between the results
interesting. Fig. 6 is a graphic illustra-
tion of the results of the first and Fig. 7
of the second series of tests. There are
differences in condition and differences
in result, the former of which refer to
the load, to the temperature and the
pressure of the steam, and to the electric
output, 700 kilowatts in the second against
640 kilowatts in the first series; also, to
the moment of inertia of the rotating
parts, w-hich increased by the change.
The latter refer to the steam consump-
tion, to the utilization of heat, and there-
fore to the economic efficiency; also to
the losses, both internal and external,
which influence the said efficiency.

Of the greatest interest is the effect of
the change of construction on the gen-
eral economic efficiency, which is the
ratio of utilized to available heat drop.
At full load the economic efficiency in
the second series of tests is 61 per cent.,
or 2 per cent, higher than in the first
series; at three-fourths load the efficiency
is also 61 per cent., or 4 per cent, higher
than it was at two-thirds load in the first
series. At one-fourth load the efficiency

Oi 234567 S9I0II

S+eam Pressure behind Governing Valve rcNvtn

Fic. 7. Results of Second Series of Tests: Pitch 0.30 .\nd 0.47
Inch; Blade Provided vs'ith Shrouds

and illustrated in Fig. 3. In addition, the
friction of the bearings and the windage
of the different stages was to be deter-
mined, and a relation established be-

is 60.5 per cent, against 57 per cent, at
one-third load in the first tests. Thus by
covering the blade tips and reducing the
blade pitch, a considerable improvemeiA

October 3, 1911

POWER

513

in the utilization of lieat is realized, es-
pecially at three-fourths and one-third
loads. The improvement is still more
remarkable if the different groups of
stages per se are considered. Thus the
economic efficiency of the high-pressure
group at full load was 46.3 per cent.
against 40.5 per cent., at three-fourths
load, about 50 per cent, against 44 per
cent, with the old construction. In the
itiiddle group the economic efficiency at
full load was 65.6 per cent, against 56
per cent, formerly, an approximate rate
of improvement being realized for all
loads, whereas the efficiency of the low-
pressure group shows a slight decrease
at all loads; for example, at full load.
57.3 per cent, against 59.7 per cent.; at

17
16

15
14

—

—

—

—

—

—

—

A

'

/

\

?I0

V

^_

_

_

_

o

% 9
o 8

7
b
5

4
3
2

—

4

^

7-

N

V

—

—

—

—

^

^

N

__

Stoge p~.»

Fic. 8. Friction in thb Various St.\ges

three-fourths load, 51.5 per cent, against
53.7 per cent.; at one-third load, 54 per
cent, against 54.8 per cent. Possibly this
decrease is explainable by inaccuracies
in the test. This much, however, is
certain: the employment of shrouds in
the high-pressure part — on account of
the short hight of blades — effects very
marked improvements in economy, while
the low-pressure part does not materially
profit by the change. Here the addition
of another runner brings a probably
greater advantage, owing to the high vac-
uum employed, than the covering of the
blade tips.

Regarding the influence of the pitch,
the researches of Briling — referred to in
the theoretical part of these discussions
— make it evident that with stetm veloc-
ities of about 1300 feet per second and
a width of blade of 0.P7 inch, the most
favorable coefficient of velocity occurs
when the pitch equals the radius of the
blade slope, while with an increase or
decrease of the pitch the coefficient grows
smaller, first inconsiderably, afterward

faster. From the results attained by
Briling it appears that there must be a
most favorable or standard pitch for
every condition; because the smaller the
pitch, the better the guidance of the
steam; hence the smaller, also, the
losses due to eddying. On the other
hand, the smaller the pitch, the greater
the surface of metal exposed to the steam,
and also the greater the losses due to
steam friction. Since in the above tests
the efficiency of the low-pressure stages
was not improved either by the covering
of the blade tips or by the smaller pitch.
Professor Josse concludes that in the
low-pressure part shrouds are super-
fluous and, with the increased section
of the steam jet, the diminution of blade
pitch has, if any, a harmful effect.

Regarding losses, it was found that the
external losses were approximately the
same — 13.8 horsepower at 3000 revolu-
tions per minute; that is, the friction
work absorbed when the turbine is run-
ning idle, the difference of 1.1 horse-
power in the second series against the
amount formerly obtained, being, perhaps,
explainable by the different conditions of
the bearings. The internal losses, es-
pecially those due to friction and windage
of the steam decreased, there being a
saving of 16 horsepower in the second
series. The friction work of the different
groups of stages is graphically shown in
Fig. 8. It is seen that the friction w^ork
in the high-pressure group is very high
but decreases with decreasing density of
the working medium. When the economic
efficiency, as determined above, is used
for calculating the steam consumption of
the S. ,M. F. turbine under the ordinar\'
steam conditions: temperature, 300
degrees Centigrade (597 degrees Fahren-
heit I ; vacuum, 94 per cent.; pressure,
13 atmospheres i 191 pounds absolute i ;
output. 800 kilowatts; the result is 7.15
kilograms (15.7 poundsi per hour per
kilowatt.

Smoke Ahatfiiieiit

In a paper read before the British As-
sociation for the Advancement of Science.
Dr. J. S. Owens contended that, from
the point of view of smoke emission, the
present position of the manufacturer who
burns bituminous coal is that entire ab-
sence of smoke is practically impossible.

The present legal standard of "black
smoke in sufficient quantity to be a
nuisance" is admittedly unsatisfactory,
as black smoke is rarely if ever seen
and blackness alone is no measure of
the amount of pollution nor even of the
amount of soot per ton of coal burnt. The
present standard is therefore out of date.
Aleanwhile the public have to breathe
polluted air, to suffer in health and
pocket, have their buildings injured and
disfigured, and their s'inshinc cut off.

A sound standard of maximum allow-
able amount of smoke should be fixed

and enforced. Two questions must be
answered before such a standard can be
fixed: What is the best and most prac-
ticable method of measuring smoke?
What is a fair fixed maximum of smoke
emission?

To answer the first question we must
set ourselves to find out: (II The total
quantity of soot emitted in a given time;
(2l the weight of soot emitted as a per-
centage of fuel burnt; (3) the density
or weight of soot per unit volume of flue
gas; (4) the ratio only of density to a
standard; (5) the color; (6) the opacity
or blackness.

In deciding the method of measuring
we must keep in view a fair comparison
between chimney and chimney or with
standard; ease of application and sim-
plicity; reasonable accuracy; the smoke
must be measured from the outside of
the factory; the method must be capable
of use by a single observer.

The standard suggested is one of maxi-
mum density for maximum time of emis-
sion, by which is meant the amount of
soot per unit volume of flue gas. A
smoke of great density would be per-
mitted for a short time only, whereas one
of less density might be permitted for
a longer time.

The method of measuring the density
suggested is by matching the opacity of
the smoke to that of calibrated smoked
glasses, each glass representing a cer-
tain density of smoke in a column of unit
thickness, the final figure for compari-
son being obtained by dividing the den-
sity represented by the glass by the diam-
eter of the chimney. By careful con-
struction and the elimination of certain
errors an instrument can thus be made
to give a fair basis of comparison w'ith a
standard density. Doctor Owens has
devised and experimented with an instru-
ment of this type, with promising re-
sults. Certain objections will always re-
main to such a method of measuring, but
he believes that it is only along such
lines that the necessary conditions can
be fulfilled.

The Alkalies act of 1906 fixes a stand-
ard maximum of , grain of muriatic
acid per cubic foot in smoke or noxious
fumes, and it appears to the author of
the paper that the time has arrived when
the soot from furnaces should be dealt
with on similar lines but modified to suit
the location of the plant in which the
furnace is installed.

One Ion of refrigeration is the amount
of heat absorbed by the melting of 2000
pounds of ice at 32 degrees Fahrenheit
into 2000 pounds of wafer at 32 degrees
Fahrenheit, or the amount of heat that
must be extracted from 2000 pounds of
water at 32 degrees Fahrenheit to reduce
it to 2000 pounds of ice at 32 dfcrees
Fahrenheit, or 2000 < 142 = 284,000
B.l.u.

POWER

October 3, 1911

Construction Costs of Power Houses

Cost statistics, although having a cer-
tain value, often involve an element of
uncertainty as to their accuracy; that is,
there are some factors almost certain to
be overlooked in arranging the detailed
costs and summarizing them. It is true
that some of the cost is due to the fact
that it is impossible to construct a power
plant in a day or two, the construction
period usually ranging from a few months
to three years or more. During this
time it is inevitable that a portion of the
investment be tied up and there is no in-
come whatever from the plant, as the
contracts for building and apparatus
specify that certain payments must be
made from time to time during the pro-
gress of the work. There are also other
elements which affect the cost statistics
to a greater or lesser degree.

The following data have been gathered
from a variety of sources and as far as
each tabulation goes it is accurate. It is
interesting, however, to note the wide
variations which result from local condi-
tions and features of design:

By A. E. Dixon

80nO-KlLO\VATT PlJ
SE.VSHORE H.Ml.IU

JF TiiF, West .Jersev *t
AT Westville. N. J.

(H. F. Wood'.s paper before the .\merican Insti-
tute of Electrical Engineers!

liuildlne. stack.s, coal and asli-

handling machinery §.'554,000.00

Equipment 640,000.00

Total isuyj.ooo.oo

Total cost per kilowatt SllO.OO

S.'iOD-Kii.owATT Plant or the Fort Wavne &

Wabash Valley Traction Coiipany, at

Spy Run. Fort Wayne, Ind.

(Paper before American Street and Intorurban

Railway Engineers' .Association,

by J. R. Bibbins)

Cost per
Total Kilo-
Cost uatt
Building, including general con-
crete and st.fe! work, sailer-
ies, coal bunker, smoke fiur,
condenser pit, coal---tiii;ige
j>it, I'll' .?ii:!,217 IJIO 97

C'.ener.itui^' pl.ini , iiirliKhn;; tur-

bine

1.1. ■>,

M>.

rililatin!,'iliK'ts L>5ii,711 30,55
Boiler iiL.iu, iii.'In.linL; boilers,

SUp.'lli.',!!.]-., ^li.k.TS. pii.ing.

puirii-, h.'it.'i,. .s..tting,

bre.-.'hi.i-. ,.11.1 t,l!li^s llS.:il:j l.'i.02

Uondi-ii,-''. Ill, ml, iiiiluiling eon-

derisi'i^ |.iiMi|i,, piping, free

exhiiii^i^, \\,iiii tunnels and

intake screen 33,7(10 3 , flS

Coal-iiaiidling plant, including

crane, crushers, motor and

track 7, '.I'M) 0,94

Erection. .superintendence,

engineering and miscellan-
eous .".0,500 5 , 49

SOOO-KiLOWATT Plant of the Youngstovvn

& Oaio River Railroad at

We.st Point, Ohio

(C. W. Ricker's addendum to paper by .f. R.

Bibbins before the .\merican Institute of

Electrical Engineers. July, 1908)

' Total kilo-
Cost watt

General discussion of
the relative cpsts of differ-
ent parts of the plant, to-
gether with actiial data
taken from the construction
records of several 'well
kno"C)i plants.

tunnel, steel frame and
building superstructure, a.sh-
handling apparatus, coal
trestle, chimney, smoke flue
and crane 864,204 S21 . 40

Boiler plant: six 400-horse-
povver water-tube boilers,
settings, furnaces, pumps,
heater, piping and covering. 42,726 14.24

flenerating plant: three 1000-
kilowatt, three-phase, 25-
cycle, 400-volt, turbo-gener-
ators, six 375-kilowatt.
22.000-volt, step-up trans-
formers, duplicate exciters,
switching and protective
.ilipaialus 112,764 37,59

Conili'n,si'r |ilant: three baro-
iiiilni condensera with cen-
trifugal pumps, water intake
and dam, including the deep-
ening of the channel 19,224 6 41

General expense: including the
expenditures which could
not be distributed easil.v and
part of the expense of super-
vision 7,252 2 42

Complete $246,170 SS2,06

Substation equipment in power
house; two 300-kilowatt syn-
chronous converters with
five-panel switchboard 12,600 4.20

Total .S2.5.S,770 S86 . 26

30,000- 10.000-
Kilo- Kilo-
watt watt
Plant Plant
Excavation and foundations, in-
cluding condenser intake and

outflow S 8,97 S 4,89

Superstructure and steelwork . , . 19.04 3.57

Turbo-generators and condensers 26.13 24.83
Boilers, stokers, chimneys and

flues 11.11 15,75

Coal- and ash-handling equip-
ment 1,62 1 40

Boiler-feed pumps, heaters, etc. . 0 52 2 SO

Piping and valves 3.17 6 58

Exciters, etc 1.01 ..,.

Crane, air compressor, etc 0.33 0,67

Switching equipment 6.02 1.24

Water supply 0 , 83 0 38

Engineering 3 , 90 , , , .

Building and fixtures: found.a-
I ion, general excavation, con-
crete work, including con-
denser wells, overflow, ash

Totals .SS2 65 .<$62 11

In Koester's "Steam-Electric Power
Plants" the following are given:

Cost per
Kilowatt

Boston Edi.son. L sfeet plant S125.00

Interborough, Fifty-ninth street plant.

New York City 150,00

Superstructure of latter plant only , 32 00

The itemized costs in the table on page
515 are also from the same hook.

The cost of foundations will vary
greatly and is one of the elements which
local conditions affect to a greater de-
gree than most others. The conditions
vary from liquid mud to solid rock. Rock
may be desirable owing to its high bear-
ing value, but it is very expensive to ex-
cavate and the depth of excavation is
frequently fixed by the local water level.
The cost of the foundations will vary

from 2 to 12 per cent, of the total cost
per kilowatt of generating capacity. The
lower costs hold where firm sand or some
other readily excavated material with a
high bearing value is found upon the site
and the water level does not fluctuate
very much. The higher costs will be
found with rock excavation where the
character of the rock is such that it
breaks out very roughly and leaves a
large excess of the excavation to be re-
filled with concrete. Similar high costs
will be found where the underlying
strata are such as to involve the use of
long piles and a heavy concrete mat built
within a cofferdam. In some localities
it is possible to use a concrete raft, and
by keeping the bearing pressures down
the structure can be floated upon the
soil. A raft of this kind must be so
designed that it will distribute the pres-
sure, and this calls for the use of re-
inforced concrete and careful proportion-
ing to carry the heavy local loads.

Steel framing must be so proportioned
as to carry the loads, and these will vary
greatly. In many plants double, and in
one case three decks of boilers are used,
and if a heavy bunker must be supported,
the steel framing will be proportionately
heavy. The length of the span between
columns in the boiler room will be fixed
by the size of the boilers, and it is aa-
visable to keep the column spacing below
20 feet. This spacing, or a little less,
will accommodate nearly all types of
boiler. Where longer spans are used
the heavy girders increase the cost. The
minimum amount of steel will be re-
quired when the roof trusses are sup-
ported upon the walls and carry the roof
alone. This construction is objectionable
as the steel work must be held back to
suit the masonry and the masonry will
then be delayed while the steel is being
placed. This procedure will generally
cost more than when the steel is so ar-
ranged that it can be erected entirely in-
dependent of the walls. The independent
steel skeleton also permits the use of
thin curtain walls, which results in a
saving in masonry as well as in the cost
of erection.

The modern double-deck power plant.
with the boiler room at the bottom and
the operating floor above, seems designed
to get the maximum amount of power
concentrated in a possible minimum floor
space. This type of plant is an inversion
of the original double-deck plant in
which the boiler room was located above
the operating floor, as at that time this
type of construction was adopted to suit
reciprocating engines owing to the diffi-
culty 25 vears ago of handling the heavy
engine parts and erecting them on the
second floor.

One of the objections made to the
double-deck plant and the plant with a

October 3, 1911

heavy overhead bunker has been the use
of columns passing up through the walls
of the boiler settings. In one or two
cases water cooling has been employed
for the columns placed in the division
wall between the two boilers of a bat-
tery, owing to the fear that these columns
might expand unduly and irregularly
from alternate cooling and heating. The
coefficient of linear expansion of steel or
iron is about 0.00000(3 per degree Fahren-
heit; hence if such columns became
heated to a temperature 300 degrees
higher than the atmosphere they would
expand 0.001800 part of their length.
With a column 35 feet high, this would
amount to about -ji inch and might be
very serious.

The cost of boilers and stokers ranges
from 10 to 15 per cent, of the total. Brick
settings may or may not be tight at the
start, but they are rarely permanently
light, and this leakage is by no means
unimportant. Internally fired boilers or
marine settings will entirely prevent leak-

POWER

vestment than a turbine. The engine can
be used as a reducing valve and operated
with a low back pressure. The turbine
operates better with a vacuum, and this
would entail the use of live steam passed
through a reducing valve, which is a
rather expensive way to secure low-
pressure steam.

In regard to the ground area occupied,
there are a number of charts which have
appeared from more or less interested
sources, most of them demonstrating the
economy of the turbine in this respect.
It is true that the actual number of
square feet occupied may be less for the
turbine than for any other type of prime
mover and generator, but in many cases
the actual area occupied by the unit
itself is not the governing feature. When
it comes to a question of crowding the
most generating capacity into the least
possible ground area the reciprocating
engine is not very far behind the turbine,
even in large units. Vertical-inverted
and grasshopper-type marine engines

i!r.i..\Tivi: COSTS nv tikbixk and exgini-;

Excaration and fouiuiatinn

Building

Tunnel*

Fluo anfl .'itack.s

Boil*'r* an»i stokers

SiUKThealt-is

KconomiZTs

Coal- and a.sh-handling system.

Blowers and ducts

Pumiw and tank-s

PipinE. complete

Turt>o-et-neratois

Enein*^

<ien<Tator>*, engmc type

Condcn.-er?. .lurfac-

C<ind<n<'Ts. jet
Exciteis
Cran<«i
.Switclllioard
Labor .

TotaN

2 00
1 .iO
1.00
1 00

15.00
4.00
3.50

12.00

1.00
0.50
.t . .50

1.00
1.00
2.50

0.25
2.00
1.00

20.00
2.75
3.50

2.25
3.00
1 . 50

1.00
0..50
3.50

S104.5II

age Into or out from the setting. Why
they are not used more extensively it is
difficult to say.

An engine-driven unit costs more than
a turbo-generator, but the type of unit
to be selected will depend upon local
conditions. When a liberal supply of
cooling water can be secured for the cost
of pumping it is possible to maintain a
high vacuum, and the turbine may be
the most economical prim? mover. Where
cooling water is scanty and a high vac-
uum cannot be maintained, the recipro-
cating engine has many points in its
favor. The turbine is inherently a high-
speed proposition and is better suited to
the driving of alternating-current gen-
erators than it is to driving a direct-cur-
rent generator. High speeds with direct-
current machinery introduce certain corn-
mutating difficulties, particularly when
dealing with heavy loads.

In plants where a large ponion of the
exhaust steam can be utilized, a recipro-
cating unit may be a better paying in-

have been built in very large sizes and
occupy very little floor area.

The coal-handling equipment is an-
other factor and the local conditions in
some cases permit the coal to pass by
gravity from the car to the Dunker and
thence to the fire and the ashpit and the
dump. There are. however, not many
cases where this scheme is feasible. The
important factors are to simplify the ma-
chinery as much as possible and at the
same time arrange it so that it can be op-
erated by the fewest attendants. Each
case presents its own peculiarities. This
portion of the equipment will range in
cost from 2 to .=> per cent, of the total.

The last point to be considered in most
plants is the switch gear for controlling
the electric power. In many ways this
part of the equipment is the weakest
link in the chain. Some of the biggest
generating st.ilions, those which would
normally be supposed immune from seri-
ous interruptions, due to this portion of
their equipmenl. have been completely

515

put out of service for periods of time
ranging from a few minutes to several
hours or more. This part of the equip-
ment will cost from 2 to 10 per cent, of
the total plant cost.

Where continuity of operation is of
greatest importance the double-busbar
system is advisable. True, this method
duplicates a part of the control apparatus
and is more costly than the single-busbar
system, and its entire value depends upon
the price one is willing to pay to mini-
mize possible shutdowns. The Seventy-
fourth street power plant of the Man-
hattan Railway Company, now the In-
terborough Rapid Transit Company, New
York, was upon one occasion tied up
completely for some time by a piece of
wet newspaper which landed where it
cojld cause the greatest amount of
trouble.

The barometric or jet type of con-
denser costs about 60 per cent, less than
a surface condenser and the cost of main-
tenance is less. The local water-supply
conditions will have to be considered in
connection with this question. Where
salt cooling water must be used the con-
denser discharge cannot be utilized for
boiler feed and the large amount of water
required may under such conditions make
the surface condenser the c'-.eaper. In
many localities it is possible to arrange
the circulating system of a s .rface con-
dsnser so as to take adva-tage of the
siphon effect of a balanced \.ater column
and in this manner reduce to a minimum
the amount of power required for cool-
ing water; for after the water has been
set in motion the circulating pump has
only the friction head and the slight dif-
ference in head between the intake and
outfall chambers to overcome.

The question of the relative advantages
of steam or electrically driven auxiliaries
has been threshed out a number of times.
The steam from auxiliaries can be used
to heat the feed water, and this is one
of the most powerful arguments in favor
of the steam-driven unit; in fact, within
reasonable limits, the more steam used
in the auxiliaries the hotter the feed
water, and the relative economy of the
steam auxiliaries combined with the
heater will far surpass other methods of
drive as all of the heat units which are
not used in the auxiliary engines are
returned to the boiler. Klectrically driven
auxiliaries, on the other hand, increase
the load upon the main units, and should
any serious electrical disturbances arise
these vital parts of the equipmenl may
fail at the moment when their continuous
operation is absolutely necessary to keep
the plant going. The only way an elec-
trically driven auxiliary can be rendered
absolutely safe is to insure for it a sup-
ply of current which docs not depend
upon the operation of the main gen-
cr.itors. A special generating unit might
be installed for this purpose.

POWER

October 3, 1911

The Salesman and the Engineer

The requirements for a successful en-
gineering salesman differ in many re-
spects from those for the man who
handles real estate, dry goods, etc. Igno-
rance of the goods handled is one of
the most startling characteristics of the
engineering salesman; it is perhaps less
conspicuous in men handling other lines
of goods, but is probably observed by ex-
perts in those lines as well. Intentional
untruthfulness does not appear to be
common, but misstatements arising from
ignorance are frequent.

Ten or fifteen years ago the purchaser
was usually a business man, the owner,
manager or even purchasing agent, with
little, if any. technical knowledge. Then
the salesman's ignorance of his subject
did not put him at such disadvantage as
it does today. Now the technical engi-
neer is at least consulted, if not given
full sway, by the better class of pur-
chaseis — those operating large plants.

The salesman should have a thorough
knowledge of the goods he handles and
be able to answer intelligently all pos-
sible questions regarding thetri. Such
complete knowledge is not easily obtained
— in some lines it may be impossible to
give a correct answer — but an intelligent
answer showing familiarity with the sub-
ject, should be at the salesman's com-
mand.

The representative of the "Old Reliable
Manufacturing Company" informs the
prospective purchaser that the name in-
sures the goods as being the best on the
■market. To a suggestion that the price
seems high, he replies: "It is better to
pay for the name than for repairs."
The careful purchaser is not especially
anxious to do either, and he may even
suggest that he has seen an equally good
article made by the "Up to Date Com-
pany" at a considerably lower cost. This
puts any salesman in a rather difficult
position; most of them realize that it is
not good policy to run down a com-
petitor's goods and yet they are loath to
acknowledge the merits of a cheaper
article. If familar with the article
handled he may be able to demonstrate
that it has strong points other than the
name; he may lay especial stress upon
those points in which he knows the other
article to be inferior to his own, and may
even compare the two, point by point,
taking care that his statements are not
only correct but that their correctness
can be proved in a logical manner. In
some cases he may show wisdom by de-
clining to discuss the merits or demerits
of the ot'-er man's goods, conlining him-
self to the merits of his own.

The typical salesman, however, is not
equipped for a discussion of this kind;
he talks generalities, and does not realize
that the only logical conclusion which
can be arrived at from his discourse is

By H. M. Phillips

'flic average engnieernig
.uiUmikui is not .s'lijfictciitly
versed ni the details and the
operalio)! of the article he is
selling to iiitclligeiitly ini-
sjcer the (jiicstioiis ojloi
<iskcd hy the prosf^eetire
purehaser, and a bad nii-
pression results. I'urtlur^
more, sxtravaga>it elui>ns
are frequently made icJiieJi
cannot be met. Several in-
stances of siich cases are
related.

that the customer does not know a good
article from a poor one. Upon being
questioned as to the principal good fea-
tures of the article, he is likely to reply:
"It is made by the O. L. Company; there-
fore it must be the best." The purchaser
may add: "The machine appears some-
what light for our work, which is un-
usually severe. Are you sure that it will
stand the racket?" To this the sales
manager replies: "It has the O. L.
guarantee behind it; what more can any-
one want?" ".lust what is your guaran-
tee?" you ask. "To replace free of charge
any part found defective in material or
workmanship within one year from date
nf purchase."

The guarantee, to which the salesman
points with pride, will be given by any
responsible manufacturer; in most in-
stances it is of comparative!'- little value.
Material and workmanship may be per-
fect, yet the machine may break dowm
on the heavy work referred to, and loss
of life may accompany the failure. In
any event, the cost of repairs, except in
the case of very heavy machinery, would
be comparatively small and the pur-
chaser would do the work himself, or
rush the machine to the nearest properly
equipped repair shop, rather than wait
weeks for a new part from the factory
while hours or even minutes may be
worth money.

Again, the prospective purchaser may
wish to procure a steam engine. The
agent of the O. L. Company will guaran-
tee the engine to deliver its rated horse-
power on a steam consumption of 30
pounds per horsepower-hour at 100
pounds initial pressure. He can hardly
fail to know that, but if asked how much
the steam consumption will be when the
engine is run for considerable periods

with no load, or at one-quarter load, or
what the horsepower will be when the
steam pressure drops to 80 pounds, sat-
isfactory answers will be few and far
between. If the prospective customer
knows the correct answers to his ques-
tions, why does he ask? Perhaps he
does not know, but he can readily see
that the answers he receives are absurd;
he knows the O. L. Company to be a
reliable firm and asks for its bid in the
hope that it will furnish some informa-
tion as to what the apparatus can do, or
that he may be able to learn from other
sources before making a purchase.

Next comes the man representing a
firm whose reputation is yet to be es-
tablished; his strong point is the guaran-
tee which is much broader than that
usually offered, so broad, in fact, as to
excite suspicion. In some cases there
will be loopholes for escape, but fre-
quently an exceedingly rigid contract will
be offered. The apparatus may be re-
turned at the option of the purchaser at
any time within three months from the
date of delivery, no payment being re-
quired before the expiration of the three
months. It is claimed that the apparatus
will do the work at least 10 per cent.
cheaper than by the purchaser's present
method. If it has to do with the power
plant, a 10 per cent, saving in fuel (a
very popular figure) is guaranteed; fail-
ing to meet guarantees, the apparatus will
be removed and everything restored to
its former condition without cost to the
owner of the plant. How can the engi-
neer decline such a liberal offer? He
talks with the salesman and finds that
the latter is ignorant of the conditions
under which the apparatus is to be used
and knows but little of the theory and op-
eration of the apparatus itself; the strong
point is the guarantee. But unless the
engineer can be shown some logical
reason why the apparatus will give sat-
isfaction he will not purchase it; he is
more afraid of trouble and delay in the
operation of the plant than of the loss of
a few dollars, and no one will offer a
contract which will fully recompense him
for possible trouble and delay. He does
not wish to tr\' experiments which he
considers doubtful; it is his business to
know beforehand whether the apparatus
will be successful, and the installation of
an unserviceable device, even though at-
tended with no financial loss, does not
speak well for his ability.

Another point worth mentioning is that
testimonials on power apparatus are
about as trustworthy as those on patent
medicines, although many of the latter
are doubtless written in entire good faith.
What may apparently give satisfaction in
one plant under certain conditions will
be entirely unsuited to another plant
where different conditions exist.

October 3. 1911

POWER

517

To further illustrate the salesman's
ignorance of rudimentary principles, the
following examples, taken for the most
part from the writer's personal experi-
ence, are given; A prominent dealer in
electrical supplies made a bid on some
insulated copper wire and the figure was
much higher than that offered by several
competitors. He stated that it would be
economy to give him the order as he
used "Lake Superior" copper only, which
costs more than the other kinds but is
cheaper in the end because it has greater
conductivity and therefore less of it is
needed to carry a given current. He was
not certain just how much greater the
conductivity of his copper was than that
of the others, but thought it was about 30
per cent. Could this man have been
ignorant of the fact that in wire speci-
fications a conductivity of 98 per cent.
is almost universally required and that
this requirement is so easily met that an
actual test is seldom made? Some wire
is slightly better than. the standard and
shows 101 or 102 per cent., while in rare
instances it might drop to 97 or 96 per
cent, but one would not be likely to find
copper wire on the market which does
not lie between these values. Incredible
as it may appear, this statement was
made by the head of the firm to a man
whom he knew to be an electrical engi-
neer and who therefore could not be sup-
posed to be ignorant of the properties of
copper wire. If this man had claimed
superior insulating material to account
for the higher price it would have been
more difficult to deny his claim.

A salesman of a large electric company
visited a customer who already appeared
to have formed a favorable opinion of its
transformers. In the course of conversa-
tion the customer remarked: "I have been
told that there is more hysteresis in your
transformers than in any others on the
market; is that true?" For a moment the
salesman was dazed, but he soon re-
covered his self-possession and replied:
"Yes, sir, we spare no expense to make
ours the best on the market, but you will
find that they cost no more than many in-
ferior makes." Telling his experience on
his return to the factory he remarked :
"That fellow nearly had me. but I pulled
out all right; say, what is hysteresis, any-
how?" He was informed that hysteresis
is a serious loss of energy which oc-
curs in all transformers but is greatest
in those using an insufficient amount or
an Inferior quality of steel.

Another salesman encountered a cus-

Itomer as deficient in electrical knowledge
as himself; one alternating-current dy-
namo had already been purchased and
had given excellent satisfaction. As the
load had increased, another dynamo sim-
ilar to the first was desired to help sup-
ply current to the same wires. The cus-
tomer, however, desired to use a different
type of engine for the second machine
and to run it at a speed about 12 per

cent, greater than that of the first. He
asked the salesman if that would make
any difference. The salesman assured
him that it would not and took the order.
The company's engineers were fortunate
enough to learn of the proposed condi-
tions before shipment was made and
averted trouble. There was some trouble
with the customer, to be sure; but what
it he had received the machine and had
attempted to operate it?

A certain factory in New York City
has a large, well equipped and well
handled power plant. To this plant come
the 10 per cent, men, and others. The
man with a damper regulator, an ex-
cellent mechanism which really might
save 10 per cent, in many plants but
would be useless under the operating
conditions of this one, does not stop to
find out what the conditions are but is
perfectly willing to make his guarantee.
Grate bars, chemicals for sprinkling the
coal, cleaning devices for the boiler,
chemicals for preventing scale in the
boilers, ball bearings for the shafting,
compounds to prevent the slipping of
belts, patent lubricants; all are offered
with the guarantee of a large saving in
fuel, generally 10 per cent., and no in-
quiry as to the operating conditions. The
engineer of this plant recently remarked
that if he were to adopt all the devices
that are offered he would have coal to
sell, for he would surely save much more
than he is now using.

An interesting exception to the general
rule was found in the man who examined
the blower system of a s;na!l plant and
was anxious to replace it 'cy a more effi-
cient one; one that would save a large
amount of power. As a modest man. he
did not like to say just how much would
be saved, but after some urging he stated
that it should be between 50 and liO
horsepower. It was conceeded that this
would be doing very well, as the system
which he examined was using only 30
horsepower. Why did he not follow the
example of the others and give a per-
centage?

One company, through sad experience,
has found it best to issue strict orders to
its salesmen to forward all engineering
questions to the factory. This may be
safe in a way but the customer docs not
like to wait a week, or possibly several,
for the answer to some simple question.
Few people like to deal with a man who
docs not know his business, and the
salesman with these instructions must
tacitly admit the fact whenever a question
is asked.

Another recruits its sales force from
young men who have taken a long ap-
prenticeship course at the plant and have
been actively engaged in the manufac-
turing of the articles they arc to sell.
This is good, hut not complete; the edu-
cation is largely that of a mechanic and
too narrow. The man. comparatively
young, can tell just how the thing is

made, which is good ; but he knows com-
paratively little of the conditions govern-
ing its design and under which it will be
used after it leaves the plant. Manufac-
turing conditions change rapidly, and un-
less he is careful to keep his laboriously
acquired knowledge uptodate it will be of
little use. The time spent in preparation
seems hardly commensurate with the re-
sult.

Others engage such salesmen as they
consider desirable and give them from
two or three weeks to as many months
at the factory to learn the business. The
salesman himself, however, generally
considers that keeping a man of his
caliber from active work for this length
of time is time and money wasted, which
appears to be the case in many instances,
although not in the sense intended by the
salesman. The man is self-satisfied from
the start; he does not want to become an
engineer, he wants to sell.

The agent whom the purchasing en-
gineer longs for but seldom has t'.ie
pleasure of meeting is the man who is
familiar with the mechanical construction
of his goods, with their operation under
the varying conditions found in actual
practice and with the general theory gov-
erning both. A man with a mind which
through education and experience will
readily grasp such new problems as the
purchaser may present; with the faculty
nf expressing his views clearly and con-
cisely and of sticking to the subject at
hand, will not guarantee a machine to do
the work before he knows what the work
is to be. After learning just how a re-
sult is accomplished with the machinery
already installed, he may guarantee a
saving of 10 per cent, in fuel or labor,
but he will not do it blindly; moreover, he
will be able to show the engineer just
how and why the saving is to be accom-
plished.

As has already been stated, not much
confidence is placed in a guarantee alone,
and the salesman who can show how and
why will hardly need to offer one. In-
stead of 10 the saving may be 1 per
cent.; the purchaser may know that it
can never be detected on the accounts
but he is nevertheless convinced that the
apparatus will accomplish it as it has
been proved to him that it will. A saving
of 1 per cent, on the fuel hill of even a
small plant is no small item, and the
same may be said of labor where a con-
siderable number of hands are employed.

A pleasing personality, tact, fluency,
perseverance, an effective entrance and
exit, a knowledge of the psychological
moment, are, of course, desirable qualities
in all salesmen, but a full equipment of
these lines will in many cases be counter-
acted by an insufflcient knowledge of the
subject on which he is speaking. The
buyer has in many cases learned to sicel
himself against the former qualifications,
even to regard them with suspicion, but
the latter takes him by surprise.

POWER

October 3. 1911

W_^ ^i^

Why the Electric Drive Has
Not Always Given Satis-
faction

By Henry D. Jackson

During the past fifteen years I have
had opportunities to investigate power-
plant installations, particularly those con-
• nected with factories, and have had an
excellent opportunity to see why the elec-
tric drive in many cases has not proved
satisfactory. The causes may be divided
into three distinct classes: First, the
motors; second, the wiring; third, the
cost of power.

Motors

The principal trouble due to the motors
has been the use of very high-speed ma-
chines, with the main object of reducing
first cost. This has led to the necessity
of very large pulley ratios or special
methods of drive, such as chain or gear,
none of which has worked out satisfac-
torily from the operating standpoint. The
belt drive, properly installed, proves more
satisfactory and economical than either
gears or chains, besides being very much
more quiet and flexible when changes of
speed are required.

Most establishments are more or less
limited either in head room or space be-
tween shafts, so that the diameter of the
driven pulley is limited, as is also the
center-to-center distance between the
motor and the line shaft, with the result
that with moderate-speed shafting, the
driving pulley on the motor is frequently
very small, so that with the large pulley
ratio and short distance between centers
the arc of contact on the driving pulley
is so small that the drive cannot be op-
erated unless the belt be exceedingly
tight. This brings about a great deal of
trouble with motor bearings and exces-
sive friction, both on motor and line shaft,
particularly the latter, as it frequently
happens that the line shafts are so light
that they are somewhat deflected. In ad-
dition to this there is frequently a great
deal of trouble due to belt slippage, par-
ticularly on those machines where the
load is fluctuating, making the operation
of the machines very uneven, and there
is also trouble owing to the high starting
torque of the motors and the inertia of
the shafting or the machinery, which re-
sults in the small pulleys slipping in the
belts, causing burning or throwing the
belts oft' the pulleys. The life of the
belts under such circumstances is very
short; they become either badly stretched

or "burned out" in a comparatively short
time, entailing considerable expense for
replacements and the loss of one of the
principal advantages of the electric drive,
which is uniformity of speed.

It might be said with a grain of truth
that the same general features are found
!n many belt-driven plants, namely, small
pulleys, too narrow belts, short center
distances and light shafting; but the con-
ditions are not nearly so bad in most
cases as those frequently found where
electric motors have been installed with
the principal idea of saving in first cost,
although I have found a number of plants
where the loss in speed due to belt slip-
page has been in the neighborhood of 25
per cent. There also are cases where the
wrong types of motors have been in-
stalled, such as the squirrel-cage type
where very high starting torque is re-
quired, or the slip-ring type where very
high starting torque is not required, and
where alternating-current motors have
been used when direct current would
have been far more satisfactory. Each
type of motor and each condition of fur-
nishing power has its application, but no
one is universal.

Wiring

The question of wiring reduces itself
very largely to the proper voltage for
distribution. In many plants the dis-
tances over which power may be trans-
mitted may be considerable; and if al-
ternating current is used, which is ap-
parently considered the most satisfactory,
although there is no real reason for it —
the voltage is of very considerable im-
portance, as, with large powers to be
transmitted at low voltage, the size of
the wire and the relation of the wires to
one another are matters of great import-
ance as is also the method of installation.
For example, if three-phase transmission
is used, it is of vital importance that
the three wires should run in the same
conduit, especially if metal conduit is
used; and if, owing to any special condi-
tions, lead-covered wire is necessary, the
three wires should be inclosed under the

same lead covering. This is to avoid in-
auctive effects. If large conductors are
used, it is exceedingly important that
they be located very close together and
preferably in one cable, as the mutual
induction between the wires themselves
has a very bad effect upon ■the regulation
of the circuit.

The bad effect of running a number
of single-conductor cables in lead covers
was particularly marked in one case
which came under my observation. There
were six cables in a circuit approximately
1000 feet long; each cable was of 500.-
000 circular mils section and ths six
were separated approximately 6 inches,
with no attempt to arrange them so as
to avoid inductive effects. The voltage
drop over these cables, with direct cur-
rent, would be approximately 2.5 volts,
but the actual drop (with the alternat-
ing current) during average load was
considerably over 55 volts, resulting in
a very marked effect on the speed of the
motors which were connected to the far
end. The use of a three-phase cable of
500,000 circular mils in each conductor
would have caused a voltage drop of only
5.5 volts with the same current.

The same reasoning holds true in two-
phase work, although it is not necessary
to inclose all four wires under the same
covering. The pairs composing each phase,
however, should be inclosed either in the
same conduit or same lead sheath. If a
large number of circuits are to be run, it
is particularly advisable to use three-
phase cable for three-phase circuits and
two-conductor cable for two-phase cir-
cuits in order to prevent induction be-
tween the wires.

Since the torque of an alternating-cur-
rent motor varies with the square of the
voltage, it is evident that the power de-
livered is seriously affected if the line
conductors are not arranged so as to pre-
vent or minimize induction in them and
thereby keep down the voltage drop.

For variable-speed motors, direct cur-
rent is far more satisfactory than alter-
nating, and with the use of three-wire
generators and balancers, wide ranges of
speed can be secured at a moderate in-
stallation cost.

Cost of Power

.A frequent cause of dissatisfaction
with electric drive is the cost of central-
station service. I have found that in the
average plant where electricity is pur-
chased the cost has been much greater
than the owners anticipated. This has
been due to two causes: First, the df

October 3, 1911

POWER

519

sire of the company supplying the power
to have the motor installation cost the
owners as little as possible, in order to
induce them to adopt it; this incites them
to recommend high-speed motors, with
the consequent troubles already men-
tioned. Second, because the cost of the
power supply has been far greater than
was anticipated. This latter has been
true largely owing to a mistaken idea on
the part of the supply company as to how
much power had been costing the plant
owner, and also to the plant owner not
knowing what his power was actually
costing him.

When the electric drive was installed.
it cost a considerable sum of money, and
naturally the interest. maintenance and de-
preciation on the installation are charged
up as power cost. In addition to this,
there is a charge by the power company
designated the "service charge"; that is,
a charge based on the total horsepower
of motors installed, this being fixed re-
gardless of the electrical power used.
For a plant operating at full capa-
city, this is a very small item and is not
serious; if, however, the plant is partly
shut down or operating on a light load,
the service charge amounts to a good
deal and is a very considerable sum per
unit of manufactured product. Besides
this there is usually a charge based on
the maximum demand, that is to say, a
charge for a certain number of hours per
month based upon the power used during
a stated period at any time during the
month, and anything beyond this is
charged at a very much lower rate. This
"'requently works a hardship, for it may
be that during a very few days out of
each month the plant is operating at full
load, with a large maximum demand.
During the rest of the month it may be
operating at light load, so that the power
cost per month based on the maximum
demand is large, although the amount of
power used may be small compared to
those months where the plant is operat-
ing continuously at full load; and the
total charge per unit of output would be
much greater. These Items are usually
entirely lost sight of during the talk with
the central-station man, and the impres-
sion is gained that the cost per kilowatt-
hour will be small or will be whatever
may be his minimum-demand charge.
The central-station man as a rule em-
phasizes the cost of power as shown by
his minimum rate and not his maximum,
so that the impression gained by the
purchaser is that all of the power will
be paid for at the minimum rate. A num-
ber of plant owners have found that their
total power demand has been so small
that they never reach the minimum-de-
mand rate, with the result that their
power bill is double or treble what they
had expected; in addition to this they
have to pay for the healing of their build-
ings which formerly, to all intents and
purposes, they had obtained for nothing.

With purchased power, it is, therefore,
advisable to investigate very carefully in-
to the wording of a contract, study care-
fully the maximum demand, the service
charge and other phrases of the contract
as to what they mean, and add to the es-
timate of power cost what it will cost for
heat, since when power is generated by
steam, a large portion of the heat at any
rate can be obtained from the exhaust
of the engine.

Where the owner installed his own
generating plant it has not been uncom-
mon to find that alternating-current gei-
erators have been put in where direct
current would have been far more satis-
factory, both as regards first cost and
operating cost; also, that the power fac-
tor of the alternating-current plant had
not been seriously considered and, con-
sequently, the generator was not suffi-
ciently large for the purpose and the
regulation was exceedingly poor, result-
ing in great variation in speed of the
machinery — a result which is directly op-
posite to what should naturally be ex-
pected from the electric drive and gives
rise to much dissatisfaction among the
employees as well as causing a reduction
in the output of the machinery. Belted
units are frequently found installed with
altogether too short belt centers, result-
ing in a great deal of trouble with the
belts, besides increasing the losses; and
the type of engine is not always satis-
factory, a high-speed slide-valve engine
of verj- poor steam economy frequently
being found, which though cheap in first
cost was very expensive in operating cost,
particularly during the summer months
when steam was not required for heating.

In other words, the principal reasons
why the electric drives have in many
cases not proved satisfactory are a lack
of thorough investigation by the owners
into the power conditions, a lack of
knowledge of what could or could not be
done in their plants, or either the ab-
sence of engineering advice or unfortun-
ate selections of consulting engineers.

A Switchboard Sujjgestion
By a. E. Dixon

In many plants the rheostats or con-
trollers are operated from the front of
the switchboard by means of handwheels,
the connection from the handwheel spin-
dle to the controller spindle being made
by sprocket wheels and a chain. It is a
good plan to inclose the sprocket and
chain in a light housing of wood or some
other insulating material adapted for the
purpose. This housing will prevent any
danger of the chain coming in contact
with a live portion of the circuits behind
the board, should it accidentally part. It
is not very much trouble to apply the
housing and if may save a shutdown of
the unexpected variety, accompanied by
fireworks, or a dangerous and perhaps
fatal shock from the handwheel spindle.

Similar means can be advantageously
used for inclosing the operating levers
of high-tension oil switches, etc.. or catch
hooks should be provided to prevent the
rods from falling if a pin drops out.

Electric Drive for Textile

Mills

By W.. H. Booth

It is doubtful whether electrical driv-
ing has yet shown any advantage, when
applied to a new factory, as compared
with a modern rope-driven one. A cot-
ton mill is, of course, the last place for
electrical driving to show results, for
there is so little machine-driven shafting
that it is not probable that the abolition
of shafting can compensate for the
miter-toothed gearing and electrical dis-
tribution losses. But there is one thing
electricity can do which cannot so easily
be done by mechanical means; the speed
of the ring spinning frames can be main-
tained at a maximum proper to the full-
ness of the bobbin and the output can
be increased. This is a strong point in
favor of the direct driving of each ring
frame by its own motor as against group
driving.

There have been some unfortunate ex-
amples of electrical driving and many
claims for economy and improved turn-
ing that had no basis in fact, or rath;r
the comparisons were wrongly drawn,
for it was obviously absurd to compars
the driving of an old factory forty or
fifty years old with the same factory
.when driven electrically from a modern
quick-running engine. An instance came
under my observation where a man placed
a ring frame in the cellar of his old mill
and drove it by belt from a pair of old
beam engines running at 40 revolutions
per minute, badly out of balance, and
with a light flywheel. The frame was
next driven electrically from an engine
with three cranks instead of two. at a
speed of 125 instead of -10, and, of course,
with many times the flywheel effect, and
the spinning frame showed a better out-
put. But the increased production of the
frame per spindle was fairly well
counterbalanced by the reduced number
of spindles necessary to allow for the
space at the frame end occupied by the
motor. Advocates of electricity should
pay attention to the improvements that
electricity can efTcct which are beyond
the power of mechanical means, for it
is in such special directions that elec-
tricity must justify itself.

Obviously if is no comparison to say
that there are electrically driven niiils
in America or in Italy when such elec-
tricity is watcr-gcncratcd. So there might
be in England if there were any wafer-
falls. There are the equivalent of water-
falls in the shape of blast furnaces pour-
ing to waste the gas that would produce
a million horsepower, and against elec-
trical driving from water or waste gas

520

there is no argument unless a certain
recent Italian practice be accepted. There
electricity will not be acepted if it can be
avoided. More direct methods are used,
for little water turbines are built into the
ends of the spinning frames and driven
direct by high-pressure water brougnt
into the factory, thus avoiding the heavy
cost of dynamos and motors. Such a
system is not perhaps possible at a very
long distance from the waterfall, but it
is one solution of the mill-driving prob-
lem that shows us that we cannot or
must not dogmatize in these matters.

Selectinjr the Right Motor for
the Job

By Frank Williston
In small plants, it is generally the
custom for the "old man" to come to the
engineer for advice regarding the proper
motor for any given job. Hasty con-
clusions and approximations will go for
a while, especially in alternating-cur-
rent work, because the modern induction
motor is credited with being able to
do almost anything. But later on when
the factory has grown, the "old man"
will call in an "expert" who will criticize
the entire layout, justly, by using a few
simple rules which the engineer could
have applied himself in the first place.
My experience has been that next to

P O W E R

speed motors give higher efficiencies and
better power factors as well as lower
first cost.

Another consideration is the selection
of speeds which are standard for motors
carried in stock or easily turned out by
ihe manufacturer. A brother engineer
recently experienced considerable delay
and loss by insisting on buying 15-horse-
power motors to run at 1800 revolutions
per minute instead of the standard speed
of 1200 revolutions per minute, though
the motors do not differ much in cost.

Whatever combination is selected, the
pulley on the motor should be of the
standard diameter selected by the manu-
facturer, as better belt speeds and ulti-
mate savings when changes or replace-
ments are made will invariably follow.

LETTERS

Preventing Rotor Bars from
Loosening

Mr. Fuetterer's letter in the September
5 issue of Power, on the trouble he has
had from the loosening of the rotor bars
of squirrel-cage motors, interested me
because I have experienced this trouble
in several types of motors that have
come under my charge. The remedy that
Mr. Fuetterer suggests, of bolting the
bars to the end rings, is not always

T.vpt-

Direct connected

Chain drive

Belt drive

Belt drive

Distance

between ) Cost of
Cenfens I Motor

Cost of

Con-
nection Total Cost

517T 00 [ S 1 00 SI'S. 00

130 00 64 .50 I 194 50

97 20 11.50 t lOS 70

64.00 13.00 ! 77 00

.3 feet
6 feet
9 feet

the errors in size, which are never very
large on the part of the engineer who
uses his steam indicator or moves around
an old motor for a tryout, the greatest
errors in judgment come in the selection
of the speed of the motor. A recent case
in hand illustrates the wide range of
speeds from which the purchaser is re-
quired to choose the best. An overhead
shaft with a load of 5 horsepower at
500 revolutions per minute required a
motor drive. The various drives possible
are as specified in the accompanying
table.

The problem started with the elimina-
tion of those drives which are not ad-
visable owing to weight (in the case of
the slow-speed motor) or the long dis-
tance required between centers (the 1800-
revolutions per minute drivel. Both were
eliminated in this case. The next de-
cision, between the two medium-speed
drives, was decided in favor of the one
at 1200 revolutions per miniite on the
basis of first cost and the fact that the
inclosed chain drive would not bring in
any added financial return in this case.

In cases similar to the foregoing it
is well to remember also that the higher-

successful because the heat that is gen-
erated in the bars will cause the bolts
to expand and allow unsatisfactory con-
tact between the bars and the short-cir-
cuiting rings. The ill effects of this loose
contact are much aggravated when the
motor is in operation, because the cen-
trifugal force in the bars tends to throw
them away from the end rings. I have
reason to believe that the capacity of
many an induction motor is greatly cut
down due to the fact that imperfect or
even open circuits develop when the
motor is heated up and in operation.
These defects never show up when the
motor is cold and stationary; therefore
they are exceptionally hard to locate. I
have seen induction motors in which
spring washers are put under the boh
heads and on top of the rotor bars, but
this arrangement does not seem to serve
the purpose as the temper of the washers
is soon drawn and centrifugal force
again comes into play and causes the
bars to break contact with the end rings.
Upon taking one of my motors apart
recently. I was much interested in the
construction used in the rotor. .Accom-
pan\ing this letter is a photograph of this

October 3, 191!

construction which, however, does not
show the details very clearly. In this
motor, the rotor bars seem to be set in
slots milled in the end rings and heavy
copper shrouding rings are shrunk around
the outside of the end rings after the
rotor bars are in place. I have frequently
tested this construction when the motor
was hot and the outside shrouding rings
always seemed to be perfectly tight on
both the rotor bars and the main rings.

This construction seems to be exactly
along the lines that Mr. Fuetterer has

Per.manently Tight Rotor Bars

suggested for remedying the troubles he
has experienced with loose contacts, and
I thought it might interest other readeri

of Power.

Sol SiECEL.
New York.

Mr. Altnian's Displaced
Bru.sh Holder

In reply to the letter of Edgar Alt-
man, in the .August 22 number of Power.
inquiring as to what caused the displace-
ment of one of the brushes on a 35-kilo-
watt machine now used as a motor. I
should say that the screw that holds the
clamp collar to the stud jarred loose and
the pressure of the spring forcing the
brush against the commutator threw the
brush over to the position indicated by
ihe diagram.

Herbert Hill.

.Middle Falls. N. Y.

.■\n .Australian invention to overcome
corrosion and pitting in metals, especially
boilers, due to electrochemical action of
the impurities in water appears to have
met with success in Sydney. It intro-
duces, by means of dynamos, weak elec-
trical currents through the metals in-
tended to be protected, thus neutralizing
the galvanic action of the corrosive sub-
stances contained in the water. The pro-
cess was recently tested at Melbourne
University on metals immersed singly
and in connected pairs in sea water, both
hot and cold, and in dilute acids. It is
reported that all hurtful galvanic action
was suspended by a small expenditure of
electrical enersv.

October 3, 1911

POWER

521

The Diesel Oil Eni;;inc-

By Charles Day
The great difficulty most buyers ot
power-plant machinery find is in securing;
reliable figures of power costs from
people engaged in trade, except in the
case of electric-supply stations. The
writer does not know of any "body of

arge power users who systematically
; repare accounts showing their power
.osts on a uniform basis, and publish
them. This practice in connection with
electric-supply stations fortunately does
L-ive an independent and authoritative

asis, from which valuable deductions
can be made. The figures published in

Everyth ing"
n^orth while in the^as
engine and producer
industry will be treated
here in a way that can
he of use to practi-
cal men

From the averages it is clear that a
substantial gain is obtained by the adop-
tion of Diesel engines as against either
gas or steam engines, the figures being
beyond doubt substantially accurate. It

TABLE 1. AVEIiAGE (-OST PEl! KILOWATT-HOt'R SOLD

Tvpp of ,
Engine

Fuel

, LiilirifatiHK
Oil. Wasl.-
1 Storf.«, and
; Water

Wages

Hejjairs ami
Maintenanee

Tolal Opir-

ating Costs,

Pence

Load Factor

.■<leara

Gas

Diesel

0 45
0 43
0 23

(1 IIR
II 119
0 04

0.2.T
n.2.s
0 19

(1 26
(1 24
II 07

1 02
1 04
1) .13

14 7

l.T 3

U 3

the Electrical Times cover practically al-
most all the supply stations in Great
Britain, and this information combined
with information obtained direct from sta-
tion engineers has enabled the author to
determine the average results obtained in
such stations. With different types of
plant these averages for stations having
a plant capacity not exceeding 1000 horse-
power, are as stated in Table I.

The limit of 1000 horsepower was fixed
owing to there being as yet no large elec-
tricity-supply stations equipped solely
with Diesel engine or gas engines. Of
course, better results are obtained when
driving machinery which gives a better
load factor, but the causes which pro-
duce loss are. as a rule, the same, though
modified in extent. The general conclu-
sion formed from a study of electricity
stations holds good for the great majority
of power users, though perhaps not ap-
plicable to some special trades, where en-
gines can be run continuously on almost
uniform loads. It is also necessary to
point out that the figures include some
items which should not strictly he charged
against the power plant. For instance,
the wages items include figures for men
working on cables, street lamps, and in
substations, and the repairs items include
repairs to such parts. Also it is neces-
sary to mention that the figures give the
costs per unit of energy sold, not per
unit generated.

•K»lrn(l« frnni n |infifr r'-ail liefnre Sertinn
fif the Rrlltfh A««o«-Intlfni nt T*ort»imoitfh.

is also noticeable that the gain is not only
on fuel consumption, but is practically
in the same proportion on the other items
of expenditure.

The great saving shown by these aver-
age figures is confirmed by repeated ex-
periences of the author. In many cases,
although the figures guaranteed with
Diesel engines have been no better than
figures previously guaranteed and ob-

gas or steam had not been sufficiently
taken into account when considering the
guaranteed figures.

When going through cost records to
prepare the average figures previously
given, the author noticed very wide dif-
ferences of cost per unit, particularly in
the case of the steam plant. He there-
fore had the average cost calculated for
steam stations of different capacity, and
as the results are interesting, they are
given separately in Table 2.

It is to be noted that, even with the
largest steam stations, the costs per unit
generated are no better than for quite
small stations using Diesel engines, and
this in face of the improved load factor.
This is a most important point, and
shows that small Diesel stations can
profitably supply current at prices hither-
to thought to be obtainable only in
densely populated centers having large
power stations.

In all cases the figures which have
been given are operating costs and do not
include anything for interest on capital
or depreciation. It is hardly possible
to give a definite statement showing the
cost of constructing and equipping power
houses of different types, as there are so
many variable factors. However, the
author's experience of a considerable
number of estimates indicates that up to
a capacity of, say, 1000 kilowatts there
is generally little difference between the
gross capital expenditure required.

I'KliATINi; CO.ST P
STATIONS OK 111

Kli KII.OWATT-HOII!
1- IK I! I .NT SIZI<

>I.I). KOK ,sTi;\M

Station 'Capacity not
lOxcivding

Fuel

l.ilhrical-

ifiE Oil.

Waste.

Water and

Stores

Wages

lii'iwirs
and .Main-
tenanee

Tolal.
IViiee

Ixiad Kaelor

0 63
0 .Ifl
0 43
0 40
(1 42
II 37
II 33
11 10
n 34
II 3B
II 20
n .30
0 23

II on
0 Ofi
0 o.-i
0 0,1
0 04
0(14
0 04
0 03
II 03
II 04
0 03
0 (W

n 02

0 .3.')
0 27
11 2,';
n 23
0 17
0 16
0 1.-.
0 M
1) 11
0 13
0 Oil

nil

0 10

II 36
II 29
II 24
II 21
II IS
0 21
11 17
11 20
11 Ifi
II 20
II 13
0 16
II II

I 13

I IS

II "l.-i
0 K'.l
11 .SI
0 "S
11 69
11 77
0 64
II 73
(1 .M
0 lUl
0 16

.•iO(l kilowatts

7.'.li kilowalts

I.ooii kiliiHatl*

I..'illll k:lil»alls

U.IIIMP kilmwill-

:i.iii«i kil.iv.ili-

I.IHIII klll.u.ill- , ,
■..IFIIII kll(iu.,ll~
7.IMIII kll..u;,ll-

KI.IHIII kilii\(;>ll-
20.(KIII kiloHUlts
.Ml.fKHt kililU'Blts

13 3
1.-. 4

16 K
16.0
17.7

17 4
l.S s
IS. 7
17 9
22 6
10 6
20 .16

tained on tests, with existing steam and
gas engines, the Diesel engines have
shown over extended periods a saving
of .SO and fiO per cent., and in some cases
an even greater percentage, the result
being due to the fact that the Diesel
engine's average working results were
very much nearer to the guaranteed flg-
tircs than with gas or steam engines,
combined » ith the fact that the relatively
high cost of working at light loads with

whether steam, gas, or Diesel engines be
adopted.

Having now dealt with what may be
termed the commercial aspect, it may be
well to consider briefly the construc-
tional features desirable in engines for
dynamo driving. In the first place the
dynamo should be coupled direct to the
engine shafts, and not be driven by belts
or ropes, as the upkeep cost of these
is considerable; also, with belt or rope

522

drive, the space occupied is considerable.
Direct coupling of dynamos means that
slow-speed engines are to be avoided;
otherwise the cost of the dynamos is very
high. For speeds which are not slow,
engines of the multi-crank type become
desirable; otherwise serious vibration is
likely to be caused. For the same reason
it is important that the distance between
the center lines of the cylinders of an
engine be reduced as much as possible.
If far apart, as, for instance, in the case
of a cross-compound steam engine with
dynamo between, then each cylinder or
line of parts will produce its own vibrat-
ing effects on the foundation without be-
ing materially influenced or counteracted
by the other.

For multi-crank engines with cylinders
close together the vertical construction
is much more suitable than the horizontal,
and gives much better accessibility. Also
any unbalanced inertia forces do not
tend to slide the engine about, but merely
increase or decrease the pressure on the
foundations.

The vertical design is also better from
the point of view of piston wear. Multi-
crank engines are also advantageous as
regards speed regularity during each
revolution, which is a point of importance
when driving alternators in parallel.
When high-speed engines are adopted,
the multi-crank vertical type becomes im-
perative, and experience has shown that
forced lubrication to all bearings is very
much better than any other system of
lubrication. Also, with high speeds the
crank chamber should be completely in-
closed; otherwise a lot of lubricating oil
is thrown about. This complete inclosing,
combined with forced lubrication, is, in
the author's opinion, an absolute es-
sential for high-speed engines, whether
steam, gas or oil.

With the first few oil engines to which
forced lubrication was applied a portion
of the lubricating oil got drawn up into
the cylinders. Detailed improvements in
construction have, however, completely
overcome this, and now the oil consump-
tion is quite as low with the forced lubri-
cation as with the ordinary systems. For
moderate speeds of revolution, ring lubri-
cated main bearings are thoroughly sat-
isfactory combined with centrifugal lubri-
cation to crank pins. With such an ar-
rangement less complete inclosing meets
all requirements of cleanliness.

The heat efficiency of the Diesel en-
gine, though far from perfect, is still
much better than any other heat engine,
as is readily seen from the fuel consump-
tion, which is 0.44 pound of fuel oil per
brake Iiorsepower per hour. The fuel
consumption is also low at partial loads;
being 0.45 pound at three-quarters load,
0.47 pound at half load and 0.62 pound
at quarter load.

These are not "records" but everyday
figures, and for engines of moderate size.
With larger engines the fuel consumption

POWER

is rather lower, but increase of size does
not give anything like the improvement in
fuel consumption that occurs with steam
engines.

Owing to the high economy at light
loads it is often found distinctly ad-
vantageous to run a Diesel engine in
preference to using a storage battery.

The oil generally used is residual
petroleum; that is, the residuum left from
petroleum after the lighter oils have been
distilled off. The increased demand for
gasolene will certainly tend to increase
the further supply of residuum, while
the opening up of new oilwells in various
parts of the world is steadily increasing
the oil supply.

The fuel oil used can be almost any
of the fuel oils which are used for boiler
firing, and a wide variety of oils can be
used with no alteration of the engine,
this being probably explained by the fact
that an atomizer which will sufficiently
atomize a thick viscous oil can easily
atomize the thinner oils. The use of oil
fuel carries with it obvious advantages
in the way of ease of handling and of
cleanliness.

The question may naturally be asked
whether Diesel engines are suitable for
long periods of continuous running. In
reply to this the following instance may
be quoted:

.At the Birkdale Electricity Works a
Mirrlees- Diesel was installed a little over
four years ago. The station engineer
recently made a report which showed
that the engine had, on the average,
worked 23^1 hours out of every 24 hours
throughout the four years, or an average
stoppage of about Im hours each Sun-
day.

CORRESPONDENCE

Trouble from Long Exhaust
Pipes

In reply to H. H. Delbert's letter in
the issue of August 22, asking why a
long exhaust pipe prevented a 3-horse-
power engine from running, I would say
that the cause was back pressure di-
rectly due to the use of such a length
of pipe. The velocity at which the gases
start out of the cylinder at the instant
the exhaust valve opens is very high;
the gases should therefore be allowed
to escape as freely as possible in order
that equalization of pressure may be
practically established by the time the
outer dead center is reached.

The use of an extremely long exhaust
pipe might readily prevent this condition
from being realized. Before the exhaust
gases can be discharged into the at-
mosphere they must set in motion the
entire column of air in the exhaust pipe.
The heat of the gases also causes the
air in the exhaust pipe, nearest the en-
gine, to expand very quickly, while the

October 3, 1911

air at the far end of the pipe would be
still cold, thus increasing the back pres-
sure that the engine would have to over-
come.

From the foregoing, it is evident that
in the case of a small engine the back
pressure might prevent the engine from
running.

Donald Renshaw.

New Orleans, La.

[Air. Renshaw's argument is sound
except as to the alleged increase in back
pressure due to the heating of the air
in the exhaust pipe. The specific heat
of air is very nearly equal to that of ex-
haust gases. Consequently, the loss of
heat by the exhaust gases would cause
them to shrink about as much as it
caused the air to expand, and the back
pressure would not be increased serious-
ly, if at all. It might possibly be de-
creased by reason of the fact that the
quantity of air is much greater than that
of gases, and the transfer of any quan-
tity of heat to the air might cause more
shrinkage in the gases than e.xpansicn
of the air. — Editor.]

I have had difficulty in operating an
engine with a long exhaust pipe, some-
what like the trouble described by Mr.
Delbert. My engine is a little one, gov-
erned on the hit-and-miss principle and
provided with an automatic inlet valve
and an arrangement whereby the gov-
ernor holds the exhaust valve open when
an explosion is to be missed; this pre-
vents the suction of the piston from
pulling the automatic inlet valve open.

The exhaust pipe is 25 feet long and
1 found that when the governor came into
action the intake valve would be sucked
off its seat just as though the exhaust
valve were closed. When I disconnected
the exhaust pipe, the engine worked all
right, so I came to conclusion that the
inertia of the exhaust gases in the long
pipe was the cause. I put a suction valve
in the exhaust pipe, right at the engine,
w'ith a spring weaker than the spring of
the intake valve of the engine, and after
this change the engine ran without any
trouble. Whenever the governor came
into action, the valve on the exhaust pipe
opened, proving that my view of the d ffi-
culty was correct. The suction valve
also lifted slightly from its seat £t every
exhaust of the engine, showing that the
column of exhaust gases in the long pipe
had considerable inertia.

Charles A. Street.

St. Louis, Mo.

Energy from Niagara falls, including
operation on both sides of the river, is
being used at the rate of 126.000 horse-
power for electrochemical purposes, 56,-
200 horsepower for railway ser\'ice, 36,-
400 horsepower for lighting and 54,540
horsepower for industrial ser\-ices, the
total being 273,140 horsepower. This is
about 5 per cent, of the power available.

October 3. 1911

POWER

Keep tlie Heater Clean

It is surprising how much dirt a good
heater will separate from the water in a
day's run. For economic reasons a heater
should be kept clean.

I have an open heater and every morn-
ing after starting up I open the blowoff
valve, and allow the city water to enter
from the top and mix with the exhaust
steam, thus thoroughly heating the water
and flushing the heater. Then for fear
there might be some dirt left at the bot-
tom of the heater I open the city pres-
sure valve on the suction side of the
pump, thus forcing the water through
the pump into the bottom of the heater;
by so doing I have a clean heater for the
day.

A closed heater can be treated in a lilce
manner. With a clean heater the soda
solution will act on the remaining scales,
while before it was simply a hand-to-
hand fight between the mud and the com-
pound.

Some time ago I >as working in an of-
fice building where it was the rule to run
boilers six weeks before washing out.
When looking in the boilers for the first
time I was amazed to see how fairly
clean they were, which I later attributed
to the fact that the returns from the ex-
haust were used and the same water
was used over and over.

John Wallin.

Chicago, 111.

Engine Room I/Og Book
I have seven large Corliss engines lo-
cated in different parts of the mill, and
have had considerable trouble because
the engineers neglected to report diffi-
culties and stops they have had on the
night turn. In several cases, knocks
that occurred the last of the week have
developed into serious trouble when start-
ing Monday morning, with the consequent
shutdowns of the different departments,
whereas if I had been notified in time
the engine could have had a thorough
overhauling on Saturday and Saturday
night. To overcome this difficulty I in-
stalled a log book in each engine room.

It consists of a Ox 12-inch Standard
diary, with a page for each day. In this
book, both day and night engineers enter
all happenings during their turn, even
the most trivial items. I also have them
make a note in this book whenever re-
pairs take place, when new brasses are
put on the crosshead or crank pin or when
the main bearings are babbitted. In fact, if
is a reference book of that engine rooiTi.

Practical

information from the.

man on the Job. A letter

dood enough to print

here will he paid forp

Ideas, not mere words

fvsntcd

When I make my dai'y rounds each
morn-ing I always look at this book as
it keeps me better posted than I would
be otherwise. The engineers also take
a great deal of pride in this book, and
by putting down the . daily happenings
and not trusting to memory they can tell
exactly how long a part has worn, and
what service it has given.

Since starting this book I have noticed
that we have had fewer stoppages than
heretofore, as my attention is called to
defects and they are fixed up at the
end of the week.

A. Rai'ch.

Swissvale, Penn.

Improved Stop Valve*

Almost every valve used in pipe con-
nection in an engine room leaks more or
less. I have had troubles with valves in

Improved Stop Valve

boiler rooms which I found were caused
by faulty construction of the valve and
not poor management on the part of the
engineer.

In the nrdinar>' stop valves I have
used the bearing surface between the

tlip llliintrntlnn.

Ilil« li-lti>i'

valve and its seat is one conical sur-
face and if the valve wears irregularly
or a bit of dirt gets in the bearing sur-
face, the valve will soon begin to leak.

To remedy this defect I designed the
valve shown in the accompanying illus-
tration, which is a sectional view.

The valve disk is made with an annular
inverted V-shaped groove which fits a
corresponding elevated surface on the
valve seat.

This construction gives the valve disk
and seat two bearing surfaces, so there
is little chance for steam leakage. If
the valve leaks at the inner surface, the
steam expands in the cavity of the groove
and forms a water packing, and thus
prevents further leakage.

The distance of the center of the groove
from the center of the valve differs
slightly from that of the center of the
valve seat's head. When the valve disk
is pressed against the seat on the outer
edge it springs in to some extent and
gives a uniform pressure on the valve
seat, thus keeping the valve nonleakable.
Yaekichi Sekiguchi.

Tokio, Japan.

Running; C'orli.s,s Engine with
One Steam Naive

Some time ago I had a discussion with
a number of engineers and later with the
senior engineering students at the Wor-
cester Polytechnic Institute as to what
would happen if the connections to one
of the steam valves of a simple Corliss
engine should break and leave the valve
open and, if the engine ran at all under
these circumstances, what kind of indi-
cator diagraiTis it would give.

There was so much dilTcrence of opin-
ion that the experiment was tried on the
I0x30-inch Corliss engine, running at 84
revolutions per minute, the test taking
place in the power laborator>' of the
Worcester Polytechnic Institute. Dia-
grams with an 80 spring were taken while
running under normal conditions; the en-
gine was then shut down, and after the
head-end steam valve had been removed,
very much to the surprise of some, the
engine was started again. The engine
could not be started by admitting steam
to the crank end, but started easily from
the usual head-end starting position. The
illustration shows the diagram taken with
the valve out. With but one steam valve
the engine would not carry as much load
as before, but the total load had to be
kept above that shown hv the head-end
diagram to prevent the engine from

524

POWER

October 3, 1911

running away. There was a large drop of
pressure between the boilers and en-
gine and in a few minutes the boiler
pressure commenced to drop.

The automatic feed-water indicator and
recorder had been showing a water rate
of about 8000 pounds of feed water per
hour, but after running some 30 minutes
without the valve the pen was off the
chart at 17,000 pounds per hour and the
fireman was complaining that he could
not keep the water level. All of the
change in water consumption was due to
taking the valve from this engine as there

Corrosion of Hot Water
Heater

I would like to ask Power readers
what is their opinion of a trouble I am
having. I believe the matter deserves
careful analysis as it may mean a good
deal to any plant; in fact, to any and
all hot-water heating service.

Some two years ago I had to replace
the hot-water heater, which is a tank 36
inches in diameter and 96 inches long,
made with a r;i-inch shell and two ii-
inch convex heads, carrying a house

DiAGRA.MS Obtained with One Stea.m Valve Removed

had been no change of load on the other
engine that was running at the time. The
pressure in the exhaust pipe fluctuated
rapidly between 10 and 25 pounds.

Members of the mechanical depart-
ment, attracted to the boiler roorri by the
evident attempt to use the exhaust head
for a steam whistle, seemed to think that
it was rather a fool trick to play on an
engine. I would fully agree with them if
it were not that its very foolishness
served to arouse the interest and enthu-
siasm of a large number of men, and in
the discussions, before and after the ex-
periment, many of them got a much bet-
ter idea of the action of the valve gear
of the engine.

In the experiment the only change
made was that of removing the steam
valve. What effect would it have on the
engine if, in addition to the above change,
the head-end exhaust valve were discon-
nected and fastened shut? What kind
of diagrams would you get from the en-
gine under these conditions?

C. A. Read.

Worcester, Mass.

Engine Knocks

.As I cannot locate a knock in a tan-
dem-compound engine, I would know
what some of the more experienced en-
gineers of Power have to say regarding
the trouble.

The knock seems to be in the low-
pressure cylinder, and when the load is
light, as it is when first starting up, it
does not sound very plainly, but as the
load picks up there is a very annoying
rap in the cylinder as it completes each
outward stroke.

W. A. Mills.

Kingwood. W. Va.

pressure of 90 pounds at a temperature
of 160 or 170 degrees. This water is
taken from the city water supply and is
heated during the winter by vacuum re-
turns, being passed through 36 feet of
4-inch brass coil in one end, the heater
lying horizontal and suspended overhead
in the boiler room. If the vacuum re-
turns do not heat sufficiently there is
36 feet of 3-inch either exhaust or high-
pressure steam coil in the opposite end
controlled by a thermostatic valve.

This tank shell, heads and iron fittings
went to pieces, all being eaten entirely
through; the edges of the plates at the
seams were all gone, the rivet heads in
places nearly gone and the shell covered
with big red rust blotches, which if
cleaned off reached well into the shell,
many times nearly through. Cast iron
could be cut with a knife as easily as
carbon, and in appearance looked very
much like it. The tank was replaced by
a ,V;-inch shell with K>-inch heads of the
same pattern now in service. I am troubled
at times by a red, rusty water which is
hard to clear up.

Plumbers are having a good deal of
trouble with water fronts and range boil-
ers, and I see no reason why it should
not affect all hot-water service.

I have had trouble with my 2-inch hot-
water meter. The iron parts went m
exactly the same way as the water heater,
and the iron inner parts are covered with
a growth similar to moss or little nee-
dles standing out all over it. By some it
is pronounced electrolysis, which I be-
lieve is wrong. Others think it is due to
boiler compound; this I also think is
wrong as I have used this compound for
years and I know it has had no injurious
effect. Further, the compound does not
reach the meter in any way as it passes
to the feed line after the water has passed

the meter. The compound could in no
possible way touch the house hot-water
apparatus. What is the cause of my
trouble and how can it be prevented?
Asa p. Hyde.
Binghamton, N. Y.

Bushed the Cyhndcr

In anticipation of rapid growth in busi-
ness, the new owners of an old shop in-
stalled a first-class 250-kilowatt auto-
matic engine and generator. Some years
later, the expected increase of business
not having arrived, the generator was
only delivering 30 to 40 kilowatts most
of the time and never more than 50.
With such light loads the governor had
a bad knock and the economy of the
engine was poor.

A bushing which reduced the diameter
of the cylinder 3 inches and made it
more in proportion to the power required,
did away with the knock in the governor
and improved the economy of the engine
very greatly. Of course, a new piston
had to be put in also.

F. D. BUFFU.M.

Scottdale, Penn.

Crank. Pin Oiler

The accompanying illustration shows
a simple oiling device. A small hole is
shown drilled longitudinally in the end.
and another in the side of the crank pin;
the holes meet. Into the longitudinal
hole a small pipe is screwed which is
made of such length that a pipe B would
be in line with the center of the crank
shaft.

Crank-pin Oiler

A pipe union C is fitted with a leather
gasket so that the pipe B can revolve
around in the main part of the union.
The pipe D and short pipe connecting
the two are stationary and supported.

An oil cup with a needle valve regu-

. lates the number of drops in a given

time. Oil flows down the vertical pipe

through the union C into the crank pin.

When the crank is down the oil will
flow to the crank pin, and at all times
the flow is assisted by centrifugal force.
Daniel Ashworth.

Wappingers Falls, N. Y.

October 3, 1911

POWER

525

Homemade Feed Water
Heater

The accompanying illustrations show
an open-heater arrangement which I have
built and which I have been using over
a year. As I was not able to get suit-
able sheet iron with which to make a
heater, I adopted the scheme of heating

This heating arrangement supplies hot
water for two 80-horsepower boilers and
there has not been any sign of oil being
carried in with the feed water. The water
is regulated by an ordinary globe valve
which has had the threads on the stem
removed.

In Fig. 2 is shown a scheme by means
of which the steam end of an engine may

Fig. 1. Arrance.ment of Pu.mps and Htaters

the cold water by using four oil barrels
after first burning out all of the old oil.

The cold-water pump A, Fig. 1. is used
to fill the tank barrels E E. By the use of
a beer barrel D, partly filled with water,
which acts as a float and actuates the
lever on the valve C. the water level
in £ £ is thus kept constant. The barrel
heater K contains sheet-iron pans and
wooden strips, about 1'4 inches thick,
which are placed between each pan, and
holds them firmly in the barrel. The
top and bottom pans are made long
enough to touch the sides of the barrel,
thus wedging the pans together. The
barrel T contains the hot-water supply
and after passing through the packing
of excelsior shavings or hay at H, it flows
to the feed-water pump B. The engine
exhaust is shown at P.

During light-load periods the cap X
can be lowered, thus allowing more steam
to pass through the heater and out
through the exhaust /,. N is an oil sep-
arator made from the body of a 7-inch
gate valve. O and S are overflows con-
nected to the waste pipe. The water
level in O should be higher than shown
in the sketch. G is a small wooden bucket
used for a float. L is an exhaust head to
keep the water from being forced out
of the exhaust pipe. With this arrange-
ment I was able to get an average tem-
perature of l!>0 degrees and when the
engine ran lightly the temperature would
rise as high as 204 degrees Fahrenheit.

be converted into a pump. I had no
means of raising the cold-water supply
for my heating arrangement, but I had a
four-hand, double-acting force pump and
an old 5x9-inch engine which I put to-
gether without the use of an auxiliary
steam valve, common to all single-cyl-
inder pumps. I removed the lap of the
valve A as shown. The arm B was at-
tached to the valve rod. The weight W
was used as a balancing weight. D and C
are catch rods which actuate the arm B.
The crosshead blocks F and G engage
with the lug E which pulls the crank arm
R from one side to the other of the

The vacuum cup may be improved by
using an air-cushion plunger, as on Cor-
liss engines. It was necessary to have
springs placed on all the valves in the
water end. Although this arrangement
may not be of the best design, it shows
its feasibility when using a vacuum cup.
C. W. Allcom.

Bellaire, O.

Scrub Engineers

When is a man an engineer?

I know of two steam plants which have
recently been erected and equipped with
the best machinery on the market. One
of them is valued at S300,000, and after
it was put in operation a carpenter who
had been working on the job was given
complete control of this plant. There
are 30 steam traps, and 10 of them are
out of working order; a 'j-inch bypass
is used to drain the systems. The valves
in the bypass pipes are kept wide open.

The traps have been operating a scant
three months. The engineer did not have
the slightest idea as to how much steam
passed through the traps in a day's run.

The other plant has a l.SO- and a 300-
horsepower engine, and a SI. 50 night
watchman was given entire control over
the engine and boiler room as soon as
they were put in operation. The engines
have never been indicated, and were in-
stalled by the laborers about the mill. I
have been in the plant on several oc-
casions, and invariably find one of the
three engines out of commission. The
managers of these two plants seem to be
perfectly satisfied with the ability of their
engineers.

It is steam plants operated by such
men which fall an easy prey to the cen-
tral station.

,1. W. Dickson.

Memphis. Tenn.

I lot Bearing.s

I have had success on most all oc-
casions by using cylinder oil and water
on hot bearings. I arrange where pos-

7~XZLL1

Fic. 2. Combined Pump Cylinders

rocker shaft, the vacuum cup pulling sihic to feed the cylinder oil to the bear-

down on the arm H, thus operating the
valve. By means of a swivel connection
to the dashpoi phingcr the rod H can be
shortened or lengthened by screwing it
in or out of the head.

ing in a small stream and feed the water
in the same way and at the same time.
This treatment will bring a bearing down
to a running temperature in a few hours.
Water should not he applied to hot

526

POWER

October 3, 191;

crank pins or main bearings in large
quantities as it may cause the cranks or
crank pins to become loose. If the heat
has had time to travel out into the crank
disk from the shaft so that it becomes
quite warm and water is applied to the
bearing in large quantities, the shaft will
contract more rapidly than the disk, and
as the engine is operating under load, it
has a tendency to loosen the disk on the
shaft. Owing to the large body of metal
in a crank disk, heat does not radiate
rapidly and they will carry heat for sev-
eral hours after once becoming hot.

Graphite, sulphur and white lead can
be used to good advantage in cooling a
hot bearing, but they should be used in
small quantities and mixed with a liberal
amount of oil; otherwise the oil grooves
in the bearings are liable to fill up. Where
the construction of bearing caps will per-
mit, it is a good plan to put a quantity of
raw beef, suet or tallow on top of the
shaft. On a rise of temperature of the
shaft it will be protected by the grease.
E. P. Baum.

Pittsburg, Penn.

• Erosion of Pump Runner

The accompanying figure shows part
of the runner which was recently taken
out of one of the circulating-water pumps
in the plant in which I am employed.
The outer end of all of the vanes in the
runner were badly eroded. When I took
the photograph herewith reproduced I
placed sheets of white paper behind the
vanes so as to bring out the nature of
the erosion as clearly as possible.

The pump is 16 inches in size and of
the double-suction, vertical-shaft sub-

electrolytic action by stray currents or
something of that sort.

But as it is claimed that alternating cur-
rent does not produce electrolysis, my
theory does not seem to hold because no
continuous current is used anywhere in
the vicinity of the pump.

I would be glad to hear from those
who have had similar experiences as to
what their explanation is and how they
overcame the trouble.

John James.

Portland, Ore.

Adjusting the Mercury
Columns

One peculiar thing concerning a mer-
cury column not usually noticed is that
the surface of the mercury in the pot
at the lower end of the glass tube varies
in hight; that is, the heavier the atmos-
phere the higher the mercury rises in the
column, hence the quantity of mercury
in the pot is reduced.

The scale is fixed securely to the

To Condenser

in reality a 28-inch vacuurri existed. I
was constantly being deceived by this
defect until suitable adjustments were
made and correct readings were ob-
tained.

Soon after this the boss, after look-
ing at the column and noting the hight
of the mercury, said, "Good for you!"
He knew what economy an additional
inch of vacuum meant, particularly
those "precious" final inches. In reality,
the error in the column was corrected
and not the vacuum.

In Fig. 1 is shown the condition of
the mercury column before adjusting
the screw at the lower end, shown at A
in Fig. 2; B, Fig. 2, is the glass tube
and C the pot of mercury.

Luke J. B. Marier.

Fall River. Mass.

Makesliift Pump \';ilve Crank

Recently my feed pump broke down
at a time when something had to be done
in a hurry to keep the plant running, as
it was the only source of feed-water
supply.

On entering the pump room I saw one
of the valve levers A on the floor, the
shaft having broken off just where it
enters the standard. I drove the key and
broken piece from the lever and cut a
piece of \s-inch pipe, which was of the
same diameter as the shaft, but 1 ; S
inches longer. I then got a piece of
maple wood and bored it to fit the pipe
to serve as the crank A. For the pin B

i

Eroded Pump Rlinnhk

Fig. I Fic.

Mercury in Columns

Pump-valve Crank

merged type, the runner and casing be-
ing completely under water all of the
time. The pump is driven by an al-
ternating-current motor. The suction pit
in which the pump is placed communi-
cates directly with the Willamette river,
water from which is used for circulating
in the condensers.

I do not think that the erosion is due
to mechanical conditions or to oxidation
or other chemical reaction between the
elements in the water and the iron be-
cause the trouble is confined to the ends
of the vanes. This fact leads me to
think that the erosion is the result of

frame, and does not move. Therefore,
the surface of the mercury should just
touch the lower end of the scale, when
the tube is filled, say, with a 28-inch
.vacuum. Then the reading would be
correct. Thus, when the vacuum is de-
stroyed the mercury in the column
lowers and the hight of mercury in the
pot rises and conceals a portion of the
scale at its lower end.

This variance in hight of the mercury
escaped my notice until recently. The
level in the pot was fully an inch be-
low the lower end of the scale, and
when the column registered 27 inches,

I bored a ' -inch hole and drove in a
hardwood doweling 3 inches long through
it.. I next filed a fiat place on the end
of the pipe to act as a keyway and at
the other end I drilled a Vs-inch hole
through the pipe. I put on the wooden
crank, drove a 10-penny nail through the
end of the wood and the hole in the pipe
at C, to prevent the crank from turning.
Then I put the pipe through the stand-
ard, put the lever on the end and drove
home the key D. The pump ran for three
weeks, until a new shaft had been made.
Fred W.\gner.
Chicago, 111.

October 3, 1911

POWER

527

fv"^ ,^f^

y ''^^^**^ ^-=^:i=^ w ^wJ-'-^-s^-'^

1^

Leaky Boiler Tubes

Some engineers seem to have trouble
with leakage at the boiler-tube ends.
Leaky tubes always Indicate to my mind
improper care, especially with horizontal
tubular boilers. 1 have charge of boilers
of this type that have run for years
without signs of tube leakage and they
are worked up to their rated capacity.

Probably the greatest cause of tube
leakage is badly scaled tube sheets; an-
other is pumping in cold water; especially
when the fire is low, one must always
have a brisk fire when pumping up;
otherwise the water will not have the
same temperature in all parts of the
boiler and will cause severe stresses in
the shell and tubes, with leakage at the
seams and tube ends and possibly cracks.
Keep the damper closed ; cold air drawn
through the furnace is harmful when the
fire is low or banked.

If possible, always fill the boiler with
water at a temperature of 140 degrees
or more. It is not of much use to ad-
vise an engineer to keep his boilers free
of scale if his employers do not furnish
him the proper facilities, but cleanliness
is the main requisite in doing away
with boiler troubles.

J. O. Benefiel.

Anderson, Ind.

Central versus Isolated Plant

In all of the recent discussions on

above subject, one point seems to

conspicuous by its absence. In many

nts great wastes occur which might

stopped at little cost, but the centra!-

ition solicitor, knowing his business,

is to point them out.

This was forcibly brought to my atten-

n some time ago, when I was called

• ■ a plant which could not carry its

iJ. and at times would have to shut

AH for several minutes until steam

'lid be raised to running pressure. The

ncr said that he had almost decided

let the central station in, as they

would guarantee to give him his power

for less than half his present cost, and

he figured he could furnish his own heat

I be money ahead.

A short inspection revealed amazing
conditions. The feed-water heater, of
the closed type, had been cut out of
8er\ice three years before because of
leaks and had never been repaired. If
was also almost completely filled with
•cale. The heating pipes refused to warm
up sufficiently with exhaust steam and

Comment,
criticism, suggestions
and debate upon various
articles.letters and edit-
orials which have ap-
peared in previous
issues

live steam was used to help out. A
foundry blower, running at 128 revolu-
tions per minute with the relief valve
blowing constantly, was driven through
four belts and a pair of cast gears. The
master mechanic ( ?) explained that by
first speeding up and then down he was
saving power. When asked why he did
not add a few more belts to the line
and run without power he was insulted.

Steam was used for heating the water
tanks and for other industrial purposes
but only one steam trap, and that not
working, was found about the plant. Al-
most all the steam lines were uncovered.
There were a lot of other equally evident
causes for loss which any self-respecting
engineer should have noticed.

The heater was cleaned, repaired and
again put in use; the heating system was
overhauled, numerous so called vapor
pipes were plugged up, and one back-
pressure valve installed. The shops were
then heated better than before, and with
exhaust steam only. The speed of the
foundry blower was cut from 128 to 65
revolutions per minute and the pressure
remained as before, the relief valve work-
ing only when some of the furnaces
".ere shut down; the belting was changed
so that one belt took the place of four
and a pair of gears; traps were installed,
the steam lines were covered, and other
glaring faults were remedied.

The coal consumption was so much
reduced that the owner was induced to
install new boilers and furnaces which
would burn a cheaper grade of fuel and
do it without smoke. This was absolute-
ly necessary as the boilers were over 20
years old— how much more nobody
seemed to know — and were of the lap-
seam species. The boiler inspector had
already cut them down to 75 pounds.

After this installation the cost had
fallen to practically the same amount as
the central-station estimate, and this in-
cluded the healing. While the electric
drive was considered, the expected sav-
ing would not warrant the investment
required for motors and an electric gen-
erator.

The central-station solicitor, when
shown the results after a six months'
run, did not bother the management fur-
ther. Had the central-station service won
out, the above wastes would have been
cut out and they would have made good,
but certainly they would not have told
anybody just where the saving w.as made.

It seems to the writer that in many
cases where the central station has won
out, they have done so not by fur-
nishing power cheaper per kilowatt-hour,
but by cutting out these , inexcusable
wastes and then furnishing less power
than was formerly required at a lower
total cost.

John Bailey.

Milwaukee, Wis.

Prevention of Wet Steam

After reading Mr. Gilbert's article con-
cerning the trouble he is having with
priming boilers, I would like to offer a
few suggestions which may prove of as-
sistance in overcoming the difficulty.

First, I note that the feed water is
had, and that different treatments have
been tried. There are lots of compounds-
that will cause priming if used to ex-
cess. I find that soda ash w-hen used
alone or, in fact, any boiler compound
containing soda ash or caustic soda — and
a great majority of them do contain it —
will cause violent priming and foaming.
The safe remedy is to use a little less
compound and give the boiler washer
more time when the boiler is off, and
see that he gets the dirt out. There is
nothing like "human" compound when
getting the dirt out of a boiler.

Second, the location of the feed-pipe
nozzles on the inside of "Mr. Gilbert's
boilers may be too close to the steam
nozzles or outlets. This arrangement
will cause priming or the pulling over of
water in case of a sudden increase of
load or the sudden starting of an engine.

Third, the construction of the dry pipes
may be at fault. They should be of suffi-
cient size and length and the perforations
rhould all be on the top half of the pipes
and of sufficient number to be equivalent
in area to the area of the steam outlet.

Fourth, a surface blowoff might be in-
stalled advantageously.

Fifth, the question of- installing steam
drums according to Mr. Gilbert's idea
raised by the insurance and inspection
companies should be looked into. There
arc certainly some commendable fea-
tures about the idea.

Sixth, some of the trouble may pos-
sibly be due to pockets in the steam

528

P O W R R

October 3. 191!

header. The proper drainage of the
header by installing traps and separators
may go a great way toward eliminating
the much dreaded shutdowns. In pur-
chasing traps, look closely to the con-
struction and be sure that all valves in
connection with the trap have the same
area of opening as the pipes used in
connection with them.

Seventh, I would suggest that even
though it is possible to carry the load on
two boilers, three boilers be used. This
will eliminate the possible necessity of
crowding the fires and will increase the
steam-making capacity with less violent
circulation.

Thomas M. Sterling.

Middlebranch, O,

Lifting Water in Boilers

In the September 12 issue, F. J. Mc-
Mahon takes exception to statements in
a recent letter of mine. He brings out
some theories on boiler operation that
are new to me. For instance, he states
that "it is the generally accepted theory
among engineers that practically all the
water in a boiler is at the temperature
corresponding to the pressure of the
steam."

If that is the case I cannot account
for the circulation in a boiler, for if there
is no difference in temperature there will
be no circulation.

I have heard that theory advanced to
explain the absence of locomotives that
have been left standing for some time
with a hot fire, and suddenly started.

Personally, I should not care to have
charge of a boiler with all the water at
or very near the flashing temperature.

As for the water in a boiler condensing
the steam, it may to a small extent. But
the amount of heat which can be trans-
mitted downward is very small in any
case and where the temperature differ-
ence is only a few degrees it can be
neglected.

Again, he says, "the amount of
feed is so small that it has practically
no effect on the temperature of the water
in the boiler."

When the fires are in bad shape, or at
clean-out time, many engineers shut off
the feed as long as they can and imagine
that it makes quite a difference with the
steaming of the boilers; in most of the
plants the feed water goes into the boiler
at a temperature of 210 degrees Fah-
renheit.

In several types of water-tube boilers
the continuity of the feed is very im-
portant; the feed is started when the
engine is and is kept on as long as the
engine runs.

Exception was also taken to my state-
ment that the pressure rises under the
conditions of a bursted steam pipe or
opening to a lower pressure.

What bursts the boiler if the pressure

does not rise; it cannot be the lower
pressure r

Large' steam pipes have burst and boil-
ers have been cut in at almost any pres-
sure over the line pressure with no dam-
age to the boilers. In other plants under
practically the same conditions, bad ex-
plosions have resulted.

It is my opinion that the amount of
water in the boiler near the flashing
point determines if the boiler will explode
when the pressure is reduced suddenly.

In my first letter what I wanted to know
concerned the water-hammer theor>'
which we have heard so much about
lately.

A few years ago, when a boiler let go,
everyone looked wise and said, "low
water," and if the engineer maintained
that the boiler had plenty of water in
it, he was not believed. Now when a
perfectly good boiler lets go, they say
water hammer.

Never having had any personal experi-
ence with a boiler explosion, but from
closely observing those boilers that have
come under my charge, in some trying
times, I cannot see the water-hammer
idea, but am open to conviction.

C. G. H,\RDEN.

Chicago. 111.

Locating Key\\ays in Corliss
^'alve Stems

In the September 12 issue, L. Johnson
gives his method of locating keyways
in Corliss valve stems. Some time ago I
had a new set of valve stems made to
replace the old ones, which were badly
worn, and the exhaust valve stems were
also bent due to pieces of a broken pis-
ton being caught in the ports by the
valves.

The valve stems were turned in the
machine shop and fitted to the valves
which were then put in place in the cylin-
der; the valve-stem crank was put on and
the valve rod screwed in about half way;
the wristplate was set central and the
steam valves set with 's-inch lap and
the exhaust valves with ,V.-inch lap; the
valve rods were screwed in about half
way to allow for lengthening or shorten-
ing, as might be required.

A combination square with center-head
attachment was then placed across the
end of the stem and crank and a line
drawn through the center of the keyway
in the crank and the center of the end
of the stem. The stem was then taken out
and as the key was ;4x/'^ inch in size, a
line was drawn on each side of the center
line '•; inch from and parallel to it. A
' J -inch hole was drilled at the proper
distance for the end of the keyway,
which was then cut out in the shaper.
.^fter the valves were assembled and the
engine started up, several indicator cards
were taken at different loads and only a

smalU amount of adjusting was found
necessary.

I believe this is a quicker and more
accurate method of locating the keyways
than that used by Mr. Johnson, especial-
ly if the stems are bent.

J. C. Hawkins.

Hyattsville, Md.

C'liri-stit- Air Steam Lngine

The description of Mr. Christie's en-
gine as published by Power is worth the
attention of engineers because it clearly
points out absurd promises of perform-
ance and suggests that a loss instead of
a gain may result in spite of the complex
design and "round-about way of getting
at it."

Without delving into the matter mi-
nutely, on the surface it appears that no
more work w-ill be accomplished per
pound of steam than if compression of
steam were carried back to initial pres-
sure, in which case the loss due to engine
clearance vanishes, as nicely proved in
Kent's pocketbook.

A mixture of steam and air may have
magic properties heretofore unknown, but
all engineers know that about one-fortieth
the volume of the medium now used,
called steam, consists of air, and trouble
enough is had with that 2' 2 per cent.
in getting it out of the condensers. How
will this engine operate with a con-
denser? How can it expand to a pres-
sure below atmospheric economically?
Why not compress air with a real air
compressor, allow- it to mingle with its
"critical" percentage of steam at the
same pressure and use the mixture in
a steam turbine or steam engine on
trial? Why build an expensive engine to
verify an absurdity? ,

W. F. SCHAPHORST.

Brooklyn, N. Y.

Mr. Rockwell's Questions

One question in particular in H. R.
Rockwell's letter, September 12 issue,
attracted my attention because, not very
long ago, I had occasion to ask a sim-
ilar question: "Will turning cold w-ater
into a red-hot boiler cause an explosion,
and if so, why?"

Two years ago I saw an article in the
September, 1909, Railway and Locomotive
Engineering bearing on the matter of
pumping cold water into a red-hot boiler.
Boiled down, it said: "Experiments were
made in Philadelphia with overheated
plates, under the supervision of the
Franklin Institute. Several boilers were
overheated and cold water was pumped
upon the red-hot sheets. The experi-
ments were ver\- conclusive that the whole
mass of the boiler, if heated red hot,
does not contain heat units enough to
raise the water to a -dangerous steam-
making pressure. All men operating
boilers should remember not to let the

October 3, 1911

POWER

529

water get low. But if by accident it should
become low, hurry to put water inside."

I wrote to a boiler company in Phila-
delphia about the foregoing quotation and
asked the opinion of its engineers. This,
in part, is what they said in reply:

"We quite agree with you that it is
better to smother the fire and let the
boiler cool to a certain extent before
pumping in cold water. For, even admit-
ting that it might not cause an explosion
to pump cold water into an overheated
boiler, there are other reasons why this
practice should not be countenanced. In
other words, our boiler experience has
not confirmed the value of the suggested
practice."

Again, the Locomotive of March, 1893,
has this to say: "* * * But we may feel
pretty confident that a longitudinal strain
of somewhere in the neighborhood of
8000 to 10,000 pounds (referring to a
certain case I per square inch may be
produced by the feed water striking di-
rectly upon the plates; and this, in ad-
dition to the normal strain produced by
the steam pressure, is quite enough to
tax the girth seams beyond their elastic
limit, if the feed pipe discharges any-
where near them."

Charles J. Mason.

Scranton. Penn.

Lubricator Coiulen.scr

In the issue of August 15, Mr. Dick-
son criticizes an article by Mr. Wallace
in the July 4 number wherein the latter
states his belief that a lubricator con-
denser should be placed at the top of the
siandpipe instead of in the usual place
at the bottom.

We are all aware that a lubricator
works properly with the condenser in its
usual position, but. just to take your mind
off the current ball scores for a few
minutes, is there not a better place for
it?

HavinR held the same view as Mr.
Wallace for a long time, I was interested
in Mr. Dickson's attempt to prove that
there was no advantage in the suggested
change. Instead of submitting any proof
of his contentions, he simply makes some
assertions which evidently we are sup-
posed to believe.

For instance, "The condenser will con-
dense a greater volume of steam in a
given time in its present position than it
would 2 feet above the lubricator." Why?
Ani again, "Mr. Wallace leads his read-
•o believe that this chamber is to con-
~e steam continuously." At least.
Mr. Dickson will surely admit there is
steam condensed "continuously" some-
where at a rate equal in volume to the
oil fed; it certainly is not condensed in
the so called condenser.

Also, let us be charitable and believe
Mr. Wallace is not the type of engineer
(?t to habitually blow out the lubri-
cator at each filling. If Mr. Dickson has

ever had the care of several engines in
a power plant he will realize that trouble
comes in bunches at times, and the filling
of a lubricator at the proper time is
sometimes neglected; at such oversights
it is handy to get the oil feed started
again without waiting for the requisite
condensation to take place.

Because makers have adhered to the
custom of placing the condenser immedi-
ately above the lubricator is no reason
why there is not a better place for its
attachmeiit.

,1. A. Carruthers.

Hosmer, B. C.

On \'ariou.s Subjects

Referring to the issue of August 22,
there are several letters on pages 291
and 295 which in my opinion are open
to discussion.

I think Mr. McCahey could have
saved some time and labor by drilling a

letter has been used for years by the
Ide Engine Works.

Mr. Beets' rig is much too elaborate.
Those shoulder bolts were made in a

Ft. 1. METHon of BurLoiNC Up Crank-
pin Shells

number of 3'16-inch holes in the sides
of the shells, as shown in Fig. 1, here-
with, and filling in the required amount
of babbitt, to build them up and prevent
side play.

While I do not wish to criticize Mr.
Hodges' piston-rod drift outfit as it is
a good idea. I do wish to point out that

r"

'i

Fir,. 2. L'sKAi. DEsir.N of Drift-pin
Ol'TUt

ii cannot always be used conveniently.
For instance, on the job he illustrates,
without taking out the wristpin, or on a
sleeve coupling. Fig. 2. herewith, shows
the outfit I use.
The keeper shown in Mr. Handley's

Fic. 3. Arrangement for Pressing in
Crank Pin

lathe and the end pieces are forgings.
The jack screw is a fifth wheel, so to
speak. Fig. 3 shows the rig used by poor
people.

Charles Bennett.
Chicago. 111.

Flvw lieel Explosion at West
Berlin

In the article under the above title
in the August 29 issue the statement is
made that the inspector, after making
an examination of the wreck, "expressed
himself as being satisfied that it was not
caused by either neglect or carelessness
on the part of anyone."

Such a finding could only be correct
if the accident had been caused by some
flaw in the material of which it was im-
possible to learn until after the accident
had brought it to light. Further in the
article the writer states that the prob-
able cause of the trouble was that "the
circuit-breaker had been expanded from
the heat of the few days past and would
not open."

If this were so, it would tend to show
that the circuit-breaker was in very poor
condition and had not been so well looked
after as the engines, whose governors
and belts, we are informed, were in per-
fect condition. The circuit-breaker should
have been considered as much a part of
the safety apparatus as were the engine
governors and kept in such condition that
it would not have failed in the manner
it did.

The article seems to indicate that there
was carelessness either by the man who
look charge of the switchboard in not
keeping the apparatus in first-class con-
dition if he had the parts with which to
do so, or else by someone else "higher
up" or in the office in not seeing that
those parts which were defective were
replaced by good ones before they were
too much worn to operate safely.

G. H. AIcKklway.

Brooklyn, N. Y.

530

POWER

October 3. 19! i

Boi/cr Room Whiteiiash

How can a good whitewash for boiler-
room walls be made?

C. E. N.

Take ; .• bushel of freshly burnt lime,
slake it with boiling water and strain the
liquid through a fine sieve. Add to it 7
pounds of salt, dissolved in warm water;
3 pounds of ground rice boiled to a thin
paste and stirred in boiling hot; Vi pound
of powdered Spanish whiting; 1 pound of
clean dissolved glue. Add 5 gallons of
hot water, stir well and let stand a few
days covered from dirt. It must be put
on hot.

IVorkiug Prcssior in Cast
Cyluider

What pressure would be allowed in
a cast-iron cylinder 36 inches in diam-
eter and J^s inch thick?

S. H. P.

The bursting pressure of an ordinary
cylinder would be calculated by the for-
mula

tensile strc n qlh X thickness
Hur sting pressure = -^^^^^

Assuming the strength of the iron to be
14,000 pounds per square inch and in-
serting the numerical values in the equa-
tion, it becomes

14.000 X 0.875 ^o t J
-21 — ^ 680 pounds

The working pressure depends on the
factor of safety used. In some cases,
such as mangle cylinders, the factor
should be high.

DyiuDiio Voltage
If a dynamo, direct current, is sup-
posed to be run at 110 volts, will it hurt
the dynamo if it is run any length of
time at 50 volts, or at anv low voltage ?
J. F. R.
It will not harm a llO-volt direct-cur-
rent dynamo to run it at a lower voltage,
but it would be impracticable with a self-
exciting machine, and if the dynamo was
separately excited the machine would
spark badly at the brushes.

Ct'fiti-ifugal Pump ivith Closed
Discharge
A centrifugal pump has a valve on
the end of the discharge pipe. If this
valve is closed while the pump is run-
ning, will it take more or less power to
drive it?

U. W. D.
The power absorbed by a centrifugal

pump is that required to take the water
which comes in at the center, practically
inert, to overcome its inertia and get it
into motion at' such a velocity that its
centrifugal force will overcome the head.
When the discharge valve is closed no
new water comes in at the center, and it
takes comparatively little power to keep
the water inclosed within the case re-
volving after it has been gotten into mo-
tion. A trolley car, for instance, would
pull much harder if a stream of men were
continuously getting in upon one side and
getting off upon the other, for every man
who got on would pull backward upon
the car with a force sufficient to over-
come his inertia.

Duplex Pump Cushion

What prevents the pistons of a duplex
pump from striking the cylinder heads?
D. P. C.

At each end of the steam cylinder
there are two ports, steam and exhaust.
As the piston approaches the end of its
travel it covers the exhaust port, prevent-
ing the escape of steam and forming a
cushion in the clearance space which
stops the piston. The larger sizes of
pumps are equipped with valves by which
the amount of compression may be regu-
lated.

Effect of J^acuHin on Turbine
Efficiency

What increase in efficiency may be ex-
pected in turbine operation by a change
of vacuum from 22 to 28.5 inches?

W. J. H.

The effect of change of vacuum upon
the water rate depends upon the type of
turbine employed, the design of the par-
ticular turbine with reference to the use
of high vacuum, the connection between
the turbine and the condenser, the load
factor and the point of departure of the
change; that is, the effect would be
greater, with a turbine adapted to utilize
the difference, if the vacuum were
changed from 28 to 29 inches than as

though it were changed from 10 to 11
inches.

S. L. Naphtaly, in reporting a test of a
10.000-kilowatt Westinghouse double-flow
turbine (see Proceedings, American So- (
ciety of Mechanical Engineers, volume i
32, page 1251 ) says, "From this and other |
tests it was found that 1 inch of vacuum I
affected the steam consumption 3 per
cent, and 6 per cent, .at full load and half
load respectively." ■

The General Electric Company's engi- '
neers figure a variation of from 1 to 1.2
pounds in the water rate per kilowatt-
hour for each inch of vacuum. R. M.
Neilson, in "An Investigation as to the
Most Economical Vacuum in Electric
Power Stations Employing Steam Tur-
bines and Cooling Towers." read before
the Institute of Electrical Engineers in
1909, assumes the effect of departure
from a 27-inch vacuum as follows:

26 27 27.5 28 28.2 2S.5

Vacuum . 25 26
Variation

in water

ratt^. per

CPJlt -f-7.3 +4.1

.1 — fi.'.'i —8

Speed of Machinerx at Xight

Why do engines, waterwheels and other
machinery seem to ran faster at night
than during the day?

L. A. F.

All natural forces act the same at night
as during the daylight and produce the
same results, and there is no foundation
for the statement that machinery seems
to run faster at night than in the daytime
for it dees not.

Gearing for High Rate of Speed

What is the best form of gearing to
run at 1800 revolutions per minute trans-
mitting 25 to 30 horsepower without jar
or noise?

L. A. M.

It is not possible to make gearing which
will run silently or anywhere near it at
high rates of speed. Inclosed in oil-
tight cases and well lubricated, accurately
cut spiral gearing similar to that used
in the DeLaval steam turbine will run
with less noise than any other.

Foaming Boiler

What makes the water in a boiler foam
and go over to the engine in large quan-
tities?

G. K. E.

Foaming in a steam boiler is caused
by foul or dirty water. The water should
be changed often and kept as clean as
possible by blowing both on the surface
and at the bottom every day.

October 3. 1911

POWER

531

Issued Weekly by the

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505 Pearl Street. New York.

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Entered as second class matter, De-
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Cable address, " Powpcb," N.
Business Telegraph Code.

CIRCULATION STATEilENT

' Of Ihia issue .30,000 copies are printed.

Sone sent free regularly, no returns from
fietcs companies, no back numbers. Figures
ere live, net circulation.

Contents

Producing Power from the Sun's Rays..

Aq Kmergency Pump .-VrrauKement

CentrifuKal Pitmp Capacity and Speed..

Experience with a Second Hand Boiler..

The Steam Turbine in Oerniany

Smoke Abatement

Construction Coats of Power Houses....

The Salesman and the Rnelneer

Why the Klcctrlc Drive Tlas Not Always
(ilven Satisfaction

A Switchboard SuKgestlon

Electric Drive for Textile .Mills

SelccllnB the Klfhl Motor for the .Tob. . .

Preventing Kotor Bars from Ixiosenlng..

Sir. Altmnn's Misplaced Brush Holder...

Th« Diesel on Kn^'lne

Trouble from I-one Kxhaust Pipes

Practical letters :

Keep the Heater Clean. .. .Engine
Room I,oe Book. . . . Improve<l Stop
Valve .... Iliinnlni: ''orliss Engine
with One Steam V-ilve. .. .Engine
Knocks .... Corrosion of Hot Water
Heater. .. .Bushed the Cylinder. .. .
Crank Pin Oiler .... Hf>memade Eeed
Water Heater ... Scrub Engineers
.... Hot Itenrlngs .... F!roslon of
I*ump Runner. .. .Adjusting the Mer-
nirr Columns. .. .Makeshift Pump
Vnlve Crank .■;23

Discussion I.ellers :

I>>flky Boiler Tubes. .. .Central ver-
sus Isolated Plant .... I*reventlon of
Wet Steam .... Lining Water In
Boilers .... Iiorallng Keyways In
Corliss Valve Stems .. .Christie Air
Steam Engine .... Mr. Rockwell's
Questions ... I.ubrlentor Condenser
On Various Subjects .... Flywheel
Explosion at West Berlin ."i27

Kdllorlals ."5.11

Wiemeld Enrms Companies' New Plant..

The Steam Turtilne for Future Work

Efficient Lubrication

While a material reduction in the an-
nual oil bill of a power plant may mean
quite a sum in itself, the total oil bill
may be so small a part of the operating
expense that even a large saving may ap-
pear negligible when expressed in per-
centage of the total cost.

Fuel is the largest single item of ex-
pense incurred in the operation of a
steam-power plant and a saving of one
per cent, in the quantity needed for a
given output may, and often does, amount
to more than the entire oil bill for the
same length of time. In the operation
of moving machinery the lubrication has
a marked influence on the power re-
quired to move it, and, next to the fuel
question, that of lubrication is the most
important apart from labor.

There are well authenticated instances
in the use of oil where changes in the
methods of lubrication and in the quality
of oil have resulted in the saving of thou-
sands of dollars per year in the cost of
operation, while the cost of the oil used
was only a few hundred dollars. It was
in the boiler furnaces that the saving
was made by the substitution of an oil
that reduced the friction of the machinery
throughout the plant.

Where one part of a machine moves
upon another, it is necessary that the
moving surfaces be separated by some
substance which shall, while preventing
the contact of the moving parts, have a
movement within itself which allows the
molecules to slide, one over or by an-
other, with the least possible resistance.
It is a fact too well known to be re-
peated that any oil is better than no oil,
but so long as to many engineers and
plant owners oil is oil, and the cheapest
is the best because it is cheap, good
money which might go to increases in
profits and salaries or to the hiring of
better men, will be wasted in unneces-
sarily large coal bills.

Good lubrication i.-. an art which is
founded on the science of common things.
There is nothing mysterious about it. and
it may be mastered in a short time by a
little patient, intelligent observation.

If a heavy body is to he moved it is
usually put on rollers, and the greater
the number of rollers used and the better
their condition the more easily the body
moves. If the rollers touch each other
there is surface friction between them,
and the smoother the rollers the less will

be this friction. If balls are substituted
for rollers the result is the same.

When a shaft has a film of oil between
it and the bearing it is as if it were sup-
ported by balls which rub against each
other as the shaft revolves, and that oil
in which the balls move most easily
against each other will allow the shaft
to move with the least friction.

As a heavy body requires larger and
stronger rollers to support it while being
moved than a lighter one, so a large
shaft carrying a heavy weight requires a
more viscous oil, one in which the mole-
cules will not so easily slip from one
another and be crushed or forced from
between the surfaces.

Viscosity is the quality of stickiness or
resistance to internal movement, and in
its use for lubrication that oil which of-
fers the least resistance to flow within it-
self, and which is heavy enough for the
work to be done, will be found to be that
which will allow the machinery to be run
with the lowest coefficient of friction.

Power from the Sun •

Direct utilization of the sun's rays for
producing power is not new; it has been
the subject of more or less experimenta-
tion for centuries, but up to the present
time it has failed to attain a position of
commercial value. It has been in some-
what the same class as the wave motor;
both are practical so far as producing
power is concerned, but the great draw-
back in both cases has been the great
initial cost and the large amount of
space occupied in proportion to the power
developed.

The sun-power plant, however, has one
advantage over the wave motor. The
latter, owing to its nature, must be set
up on the coast and is thus forced to
compete against coal where the trans-
portation rates are low. The sun-power
plant, on the other hand, finds its greatest
field for application in tropical regions
many hundred miles from the coast and
where, owing to the difficulties of trans-
portation, the price of coal is almost pro-
hibitive. In such regions the extra area
covered by such a plant is of no import-
ance and if the first cost can be kept
within moderate limits there seems to be
no reason why a sun-power plant should
not be a commercial success, especially
for irrigation purposes.

The plant described elsewhere in this
issue appears to have been designed with
the foregoing points in view; the cost is

532

POWER

October 3, 191!

not excessive and the whole installation
is easily made portable, being so ar-
ranged that it may be packed for easy
transportation. Aloreover, its inventor
has made no extravagant claims for the
plant, but admits its limitations.

The tests recently conducted at •Phila-
delphia are not conclusive; in fact, they
did little more than to demonstrate that
the plant would run and to indicate its
possibilities under the conditions for
which it was designed. Furthermore,
certain features of the equipment are
more or less crude and it is reasonable
to assume that, as the development pro-
gresses, refinements will be made tending
toward a reduction in cost and greater
efficiency.

Calculations based on the experiments
thus far made seem to point to the suc-
cess of the system; but, of course, its
commercial value can be proved only by
actual service.

The Factor of Safet}^ in Steam
Piping

In the following table is shown the
thickness of the shell in standard-weight
steel pipes and also the pressures at
which they will burst. This table em-
braces sizes of four to twelve inches in-
clusive :

Size of Pipe, Thickness of Bursting Pressure,

Inches Shell, Inch Lb. per Sq.In.

4 0 23 5880

5 0.25 5130

6 0.28 4614

7 0.30 4290
S 0 . 32 4000
9 0.34 3846

10 0.36 3648

12 0.37 3120

On the basis of two hundred pounds
static pressure it may be noted that the
factor of safety against bursting the pipe
is so high that the question of the
strength of the pipe in this respect is
eliminated. The factor of safety against
rupture from longitudinal strains due to
the same internal pressure is more than
double that for bursting.

This is based on the pipe being full
weight and having flanges which will de-
velop the full strength of the pipe.

In steam piping, however, there are
other strains than those due to the in-
ternal pressure, and unless provision be
made to take care of them the factor of
safety of the system will be seriously
affected. They are those incident to the
operation of the plant, and it is not the
pipe but the fittings which suffer from
them, and unless the layout is properly
designed they will far exceed those
strains due to static pressure.

Variations in temperature during the
operation of the plant produce movements
in the piping, and in order to preserve its
integrity, the piping between fixed points
must bend back and forth. If it does not
bend, something will break.

Records have been taken of the move-
ments of certain points on a steam main
for a period of one year, and they made

a sawtooth line. One of these records
showed that the point moved back and
forth from five to ten times per minute —
the length of travel being approximately
one inch. This movement is continuous
throughout the life of the plant.

The effect of this upon the fittings is
obvious. They must be sufficiently strong
to bend the pipe as the main moves back
and forth. It is in the fittings therefore
that the factor of safety must be most
jealously safeguarded. They not only
must be of great strength, but the pipe
must be as flexible as possible to reduce
the strain on the fittings to a minimum. '

Extra-heavy pipe will increase these
strains on the fittings and thereby de-
feats the purpose for w-hich it is installed.

From this point of view the factor of
safety with full-weight standard pipe is
higher than with extra-heavy pipe.

In the design of steam piping for mod-
ern power houses it is the usual practice
to have all fittings very heavy and strong,
and the pipe of full weight standard with
either Van Stone or welded-on flanges.

Hitjh Vacuums

When steam flows from a region of
higher to a region of lower pressure a
maximum velocity of flow is reached
when the lower absolute pressure be-
comes about fifty-eight per cent, of the
higher. After this it makes no difference
how much the delivery pressure is de-
creased, no more steam will flow per
second because the energy due to the
next increment of expansion is not suf-
ficient to get up the increase of velocity
which would be required to pass the in-
creased volume.

This fact is of prime importance in
turbine design, but it is only recently
that its bearing upon condenser practice
has been noticed. If the engine cylinder
be considered the region of higher and
the condenser that of lower pressure, and
it is recognized that the pressure in the
throat of the connecting pipe can never
be less than fifty-eight per cent, of that
in the cylinder and the velocity of flow
only that due to the expansion from the
cylinder pressure to fifty-eight per cent,
of that pressure, the futility of striving
for a high vacuum in the condenser and
then connecting it by small and crooked
pipes and restricted ports to the cylinder
becomes apparent. If the ports and pipes
are large, the pressure in the cylinder
will run down more swiftly, but it will
always be at least 1.7 times the abso-
lute pressure in the condenser so long
as the steam is flowing.

The greater vacuum will not pull the
steam out of the cylinder any faster, but
to utilize it properly ports and pipes
must be increased in proportion to the
increased volume of the low-pressure
vapor. A pound of steam in a twenty-
nine-inch vacuum occupies 3.78 times as
much volume as in a vacuum of twenty-
six inches.

Offhand Verdicts

When an accident occurs in a power
plant sometimes the cause is easily de-
termined; sometimes it is never known,
and in this case there are always those
who, even from afar, can tell offhand
just where to place the blame.

When the engineer is dead the blame
for an accident is usually placed upon
him and the matter is dropped. When he
escapes and is in a position to deny
charges of neglect or incompetency, the
complexion of things is changed and gen-
erally the facts of the case are available.

Recently a flywheel accident occurred
which, according to one contributor, was
caused by the governor belt running off
the pulley and the safety device failing
to operate. This diagnosis was evidently
the result of "absent treatment," because
later on the chief engineer, who had not
been injured, proved that this deduction
was erroneous and that the engines were
in proper condition. He found after a
very thorough and careful investigation
that the accident was due to one of the
generators becoming motored, and that
the circuit-breaker failed to operate as the
latch had expanded from abnormal heat.
The facts were no sooner known than the
long-distance verdict was rendered that
the engineer was responsible for the cir-
cuit-breaker sticking and that it was his
business to have it in working order.
Such a verdict is unreasonable.

This plant was old, the machinery was
old and was being taxed beyond its capa-
city. The company knew all the condi-
tions under which it was being run, and
it is not known that they have censured
the chief engineer. When they do. it is
time for others who are ignorant of the
facts to take the stand and give forth
their adverse opinion.

In stating the performance of an en-
gine or steam turbine, the figures are
usually given in the pounds of steam
consumed per kilowatt or horsepower per
hour. Now, while the statement may be
absolutely correct as to the quantity of
steam used and power developed, it does
not give exact information unless ac-
companied by definite information as to
the quality of the steam used. This being
known, the work done may be readily
translated into B.t.u. per unit of power
developed, which is the rational basis,
and the only one upon which intelligent
comparisons of different types of heat
engine can be made.

Some astonishing engine speeds were
noted in a recent automobile race in Eng-
land. One engine made 2490 revolutions
per minute and 1794 feet per minute pis-
ton speed as an average for the race, the
maximum speeds being considerably
higher. — Ex.

-Mcohol has not been a success in
Germany as an industrial fuel.

October 3, 1911

POWER

533

Sheffield Farms Companies'

New Plant

By \t'ARREN O. Rogers

Concentration of power-plant machin-
ery is one of the factors which permit
economical operation. In power plants
in which the output is electrical energy
the generating units and boilers are
placed as near together as conditions
will permit, and all unnecessary waste
from auxiliaries is eliminated as much
as possible.

In constructing a combination power
and refrigerating plant the concentra-
tion of machinery becomes more com-
plicated and of a different nature than
in the case of the simple power plant. The
matter of auxiliaries exhausting, either

New York City. The plant is designed
in duplicate and in order to reduce the
steam consumption all of the generating
and refrigerating machinery is driven
;rom two main steam units.

This power plant is located in the
basement of the brick building occupied
by these companies. To be in general
keeping with the cleanliness demanded by

tected by a suitable covering which is
also painted white. The combination gives
the engines a neat, clean appearance.

There are two 1(5 and 30 by 42- inch
cross-compound Fishkill Corliss engines
which are run condensing and each is
belted to a line shaft which runs the
width of the engine room at the back.
These engines run at a speed of 80 revo-
lutions per mmute and each is equipped
with a 14-foot flywheel, having a 50-
inch face. The piping between the high-
and low-pressure cylinders of both en-
gines is so designed that if the load on
one engine becomes too heavy, but not
enough for both engines to operate at
their point of greatest efHciency, the crank
on the low-j ressure side of one engine
can be disconnected and the valve gear
unhooked anri the high-pressure cylinder

Fir. 1. Partial Vifw of the Engine and CowPRF^sriR Room

to the atmosphere or into a condonser.
must be considered, and if a better meth-
od can be worked out to eliminate the
steam auxiliaries, so much the better.
These problems came up in the installa-
tion of the new re frige rating and power
plant of the Sheffield Farms-Slawson.
Hccker Companies, which has recently
been erected at 170 Manhattan street.

the nature of the work, the enjiine-room
walls arc built nf stone which are
plastered and then painted white, with
black block lines at what would be the
ioint were concrete blocks used. The
floor is made nf concrete and the founda-
tions of the engines and compressors arc
lined with dazed brick. TTie ceilinR is
painted white and all piping is pro-

nn the disconnected unit made to exhaust
into the condenser.

In the engine room arc also installed two
RO-ton double Pcnncv ammonia com-
pressors, each side having a Hx.^fi-inch
cylinder. A 1 4- foot fivwheel is fitted to
the shaft of each machine, each wheel
havinp a .V)-inch face. The machines arc
belt driven at a speed nf 60 revolutions

534

POWER

October 3, 1911

per minute from a pulley on the line
shaft. Fig. 1 presents a view of the en-
gine room.

The line shaft is quill driven, divided into
seven sections by clutches which are of
such size that they are capable of carry-
ing twice the load that the engine will de-
velop. This feature eliminates any trouble
from clutches slipping when starting up
the compressors with a high back pres-
sure on them. In the center of the shaft
are placed the two main clutches which
separate the shaft into two sections, each
section being driven by one of the two
engines. A portion of the line shaft is
shown in Fig. 2.

All pulleys are keyed to the line shaft
and the ammonia compressors are run as
long as the section of shaft carrying the
driving pulley is clutched in to the section
being driven by the engine driving that
half of the shafting. In case it is de-
sired to stop a compressor the clutch
driving that section of line shaft which
drives the machine must be thrown in
an off position. This, of course, stops
everything beyond the compressor-driving
pulley.

Two 110-kilowatt 250-volt generators
are set between the line shaft and the
engines and compressors. Both of these
machines are belt driven from the shaft
by a fixed pulley. If the generator is not
required in operation, a clutch on the
armature shaft is thrown and the gen-
erator stopped regardless as to what is
done with the shaft. This arrangement

are mounted the main switches and cir- are placed the two brine pumps. One is

cuit-breakers. a simplex steam pump and the other is a

At the extreme ends of the line shaft triple-plunger pump, belt driven from the

are two belt-driven air compressors. An line shaft.

Fig. 3. Belt-driven Cener.\tor and Clutch

adjustable idler pulley controls the op- There is also a simplex steam pump

eration of each machine. If a machine which supplies circulating water to the

is not wanted the idler pulley is lifted surface condenser from a well and one

from the belt and the belt is then easily centrifugal turbine-driven pump which is

Fig. 2. Line Shaft. Show i\r Ci

is shown in Fig. 3. These generators
furnish electrical energy to the building
for lighting and motors. The three-wire
system is employed. Each unit has its
own switchboard at the machine on which

removed from the driving pulley, or the
clutch driving the section of shafting to
which the compressor is connected can
be thrown, cutting it out.

At the back side of the engine room

held as a reserve unit for the same pur-
pose.

The two simplex boiler-feed pumps are
set in a corner of the engine room next
to the boiler room. One is held as a

October 3. 1911

P O W E R

reserve. Both have 12 and 7 by 14-inch flows through six pipes in each stack of
cylinders. coils. These coils and brine-cooling pipes
Passing to the boiler room there are are placed in a room separate from the
three 350-horsepower Babcock & Wilcox main building and are located on the sec-
boilers. Two are set on one side of the ond floor. The cooling coils are each pro-

Fic. 4. Two OF THE Three Water-tube Boilers

boiler room and the other is set on the
opposite side. These boilers are set in a
concrete pit or pan 9 feet below the en-
gine-room floor. The concrete pan was
necessary on account of the flow of water
from underground sources. Natural draft
is used and the furnaces are equipped
with dumping grates. Fig. 4 shows a
portion of the boiler room.

Coal is delivered from the street into
a storage bin under the sidewalk and is
conveyed to the boiler room in a 1-ton
coal car. which runs on an industrial
railway. The car is pushed in front of
the boilers and the charge of coal is
taken from it and fired to the furnace.

One surface condenser serves both
steam engines, although with the present
load but one engine is necessary. The
condenser contains ItKK) square feet of
cooling surface and is connected to a
6 and 14 by lO-inch steam-driven dry-
vacuum air pump. The circulating water,
57 degrees Fahrenheit, is supplied from
the well under the engine-room floor,
and after passing through a double-pipe
ammonia condenser it flows through the
steam condenser and is then elevated into
a standpipe on the outside of the
building to be used for scrubbing
and general washing purposes. The
well water is not used for ice making
on account of the quantity of magnesia
contained in it. The water of condensa-
tion is pumped from the hotwell and is
used in making ice. A plan view of the
plant is shown in Fig. 5.
There are double-pipe ammonia con-
densers, made up of 2- and 3-inch extra-
heavy pipe, 12 pipes high, and the water

vided with bottom drains. The wing in
which they are set adjoins the room in
which the can freezing takes place. The
plant has a capacity of 100 tons of ice
per da\ , which is a side issue, as the the pipe coils opposite eaCh can are pro-

Soc-Uch

535

The cooling process is to run the hot
milk down over two sections of cooling
pipes which are covered by a corrugated
easing. The bottom and third row of
tubes contain brine and the passage of
milk over the pipe casing brings the tem-
perature down to about 35 degrees Fah-
renheit, when the milk is in a fit condi-
tion to bottle ready for delivery to the
consumer.

Under ordinao' circumstances it would
be necessary to have two ammonia com-
pressors as the back pressure used in
making ice and cooling milk differ. In
this plant it requires 20 pounds back
pressure for cooling the milk and but 15
pounds for cooling the brine. These two
pressures are obtained from the same
machine as the two ends of the ammonia-
compressor cylinder are connected to a
separate line, one running to the brine
cooler and the other to milk-cooling tubes.
In case the milk-cooling tubes are not in
use an equalizing valve is opened be-
tween the two ends of the cylinder and
the same pressure is used on both sides.

In filling ice cans it frequently happens
that the can will hang up on the coils in
the brine and the man attending to the
filling will in most instances give the can
a kick to move it away from the pipe.
The can, being one-half or two-thirds
full of water, falls with considerable
force on the coil below and in time a leak
will develop. To prevent this taking place

OiHho'nf *o Condensef From Condenser

Fig.

Plan Virw of the Engine, Compressor and Boiler Rooms

main work is that of sterilizing milk, of tected by a flat strap and as the can
which I2H,000 pounds is sterilized and fills with water it rubs against the band
cooled from a temperature of 140 degrees and slips into place without catching on
to between .VS and 40 degrees. It re- the pipe coils. This and other ideas
quires but eight hours to handle this quan- were incorporated by George F. Hill, who
lity of milk, which represents 1400 cans, is the designing engineer for the corn-
each weighing f»0 pounds. pany.

536

POWER

October 3, 1911

The Steam Turbine for Future Work

The increasing volume of turbine worls.
reaching upward of 20,000,000 of horse-
power in the short time elapsed since its
advent, truly establishes the permanency
of this type of prime mover in relation
to our econoinic power problems.

For electrical supply, the turbine has
become commercially available in sizes
ranging from a fraction of a kilowatt up
to as high a power as 30,000 kilowatts
in a single unit, from the diminutive lo-
comotive headlighter to the gigantic en-
gine now demanded by the metropolitan
service stations.

(A) Complete Expansion Turbines es-
sentially rank first owing to the pre-
dominance of their use. These turbines
receive steam at the highest steam pres-
sures and temperatures, and expand it
continuously to the highest vacuum.

Where high boiler pressures (ordinarily
above 175 pounds gage) are used, but
a very small part of the turbine is re-
quired to withstand the accompanying
stresses, as high pressures are confined
within small nozzle blocks. With the
piston engine, the high-pressure cylinder
must safely accommodate these forces.
Turbine design involves no rubbing sur-
faces, so that lubrication under high
temperatures requiring special valve and
packing design and lubricants' is no
longer a factor.

The profitable use of a moderately high
vacuum is another commendable feature
of the turbine, and is readily accom-
plished without impractical or uncom-
mercial proportion of parts, such as would
become necessary with low-pressure cyl-
inders of piston engines.

(B) Low Pressure Turbines, up to
date, hold a position second to that of
the complete-expansion type, since they
are capable of receiving steam at ap-
proximately the pressure at which a
piston engine would exhaust the steam
after expanding it throughout its most
economical range of operation (boiler
pressure to atmosphere) and complete
the expansion to high vacuums with the
same degree of efficiency — doubling the
output of a noncondensing reciprocating-
engine plant without increased coal con-
sumption. The actual improvement in a
reconstructed engine plant will usually be
from 10 to 50 per cent, or more, accord-
ing to whether the plant was condensing
or noncondensing prior to including the
low-pressure turbine. The low-pressure
turbine is valuable on the following
counts:

r 1— Fuel.
)(>r- J 2— on
. . . i a- Lalior.
1^ 4— lifM'ftlrs.

( 1-Hy restoring the
utility of the engrlneB,
ng thus preserving their
aut ■! existing rated worth.

2— Ot'taining Increased

1 cjip-n-ltv at the loweat
1 iicwsilile unit cost.

By Edwin D. Dreyfus

Steam turbines are now
aza liable in units of 30,000
kilowatts capacity and near-
ly 20,000,000 horsepower
capacity have been built.

The paper deals with
early difficulties and the
modifications made, especi-
ally in the Westinghotise
practice to overcome them.

It argues for the turbines
as against the piston en-
gine, and for the reaction
as againt the impulse type,
and discusses the questions
of ratnigs a)id guarantees.

•AI)Stract of paper rend h lore the Indiui
Electric Light Association at South Hind.

f 1— By simplifying oper-
ation, "educing the
number of condensers,

I or for a former n«ui-
oi'iidensing plant prn-
viiliiig a good source

I i.r iM.iler feed.

. J— In securing better

I cyclii-al regulation, an
inli'ii-ut quality of the

;i— Tlirc.ugh the small

rise In water rale tm

1 overloads, mitigating

(^ the peak tax on boilers

The engineering features which may
surround the installation of low-pressure
turbines assume various forms, based
upon plant conditions and methods of
operation, and thus introduce these dif-
ferent provisions:

(a) Without governor. Electrically
controlled through synchronizing force
of generator.

(b) Governor control, with auxiliary
live-steam admission.

(c) Interlinking turbine and belted
engines through synchronous motor.

(d) Automatic bypassing of low-pres-
sure steam to condenser.

(e) Use of a reserve high-pressure
element.

(f) Heat regenerators, accumulators
and storage systems.

(C) Noncondensing Turbines have al-
so found a field of usefulness, to a
limited extent, however, as main units.
They are extensively used for auxiliary
service. Where exhaust steam is used
abundantly, this would prove the proper
sphere for the noncondensing design.
Should the heat supply become an im-
portant element of the utility service or
of an industrial company's operations, a

strictly noncondensing unit, or perhaps a
number of them, may be recommended,
providing the electrical load reduces in
the warm-weather months in a fair pro-
portion to the heating demand occasioned
in winter.

With the recent advance in turbine de-
sign, it is most difficult to show cause
for the use of a reciprocating engine
on the ground that it consumes less
steam when operating with atmospheric
exhaust or higher back pressures.

In the results obtained with a drum-
type Parsons turbine, with 7 pounds back
pressure, the disparity is only about 5
per cent, at full rating, compared with
an engine in excellent order, the water
rates being 39.8 and 38 pounds per kilo-
watt-hour for the turbine and engine
respectively. This difference vanishes
on loads less than one half. The
fact should be borne in mind that
with maladjustment and leakage of
valves and pistons, the steam engine may
not be constantly maintained under these
so termed test conditions. A well de-
signed turbine should not perceptibly suf-
fer in operation, and impartial tests con-
firm this fact. Further, it should be re-
membered that there is a saving in oil,
labor and investment with the turbine,
and a considerable reduction in main-
tenance expense of the distributing mains,
with entire freedom from oil, which will
greatly overshadow the slightly better
fuel economy of the piston engine. And
inasmuch as the exhaust is fed to heating
mains, the somewhat greater consump-
tion of the turbine may in no sense repre-
sent a disadvantage, but, on the con-
trary, may prove most desirable.

(D) Bleeder-type Turbines owe their
existence to the necessity for a mixed
lighting and heating supply from a cen-
tral power station. While in some plants
— chiefly large ones — the complete-ex-
pansion turbines and the noncondensing
type may be successfully coordinated to
produce the highest economies in all
directions, both the moderate- and small-
sized stations, with a dissimilar fluctua-
tion of light and heating loads throughout
the day, month and year, would find it
virtually impossible to regulate their
equipment for constantly attaining the
most efficient results. It would, more-
over, probably call for a greater station
investment to provide adequate flexibility.
In compound-condensing engine sta-
tions, it has been a very general prac-
tice in cases of this kind to draw steam
from the receiver, which becomes prac-
tical at all loads with engines having
the cutoff on the high- and low-pressure
cylinders parallel. In early turbine de-
signs, an improvised expedient was fol-
lowed to a partial extent by tapping
steam from a given stage in which the
pressure under any reasonable load

October 3, 1911

POWER

537

would not fail below that maintained in
the heating system, thus guarding against
any interference with the supply or ser-
vice. This method of operation was ac-
companied by two disadvantages: First,
a limited low-pressure steam supply only
being available through this means; be-
cause with light load the pressure at the
stage which is bled will fall below the
pressure in the heating system, and, sec-
ond, a pressure-reducing valve was nec-
essarily introduced between the turbine
and heating system, thus producing a
loss in throttling the steam.

Such diversified requirements in joint
heat and electrical demand led the tur-
bine engineer to devise a method by
which both the heating and electrical
supply would be automatically and eco-
nomically delivered in accordance with
the demands of the systems. The most
effective and dependable solution has
been the location of a pressure-controlled
valve between the high- and low-pres-
sure sections of the turbine, automatical-
ly diverting to the heating system the
exact amount of steam required and at
precisely the predetermined pressure.

This design is commercially designated
the "automatic bleeder" turbine, and in
moderate capacities promises an interest-
ing issue in the new era of utility ser-
vice.

Through the employment of a special
constant-pressure valve between a sys-
tem of reciprocating engines and a low-
pressure turbine, an exactly similar func-
tion to the bleeder turbine is secured
which deser\'es careful thought in the
extension of the older plants containing
steam engines.

Electric-power production has created,
as is well known, a demand for the tur-
bine far in excess of all other stationary
uses combined, and this result is obvious
for dual reasons: First, the turbine is
preeminently high speed and its general
adoption was realized through the suc-
cessful development of high-speed and
direct-coupled generators, and, second,
the significant growth of electricity as a
modern convenience.

Lighting, being the greater necessity,
has brought the higher-frequency (60
cycles) units forward in moderate-sized
stations. Large plants with a heavy di-
rect-current load and rotary substations
mainly employ 25 cycles. Railway and
general power apparatus have heretofore
operated at 2.S cycles, with occasional
exceptions of 15 cycles, or direct-current
generation, it being understood that as a
rule direct current for railways is ob-
tained through rotary conversion.

The foregoing partial classification, in-
cluding 60- and 25-cycle service chiefly,
comes within the realm of compatible
speeds of the turbine and generator.
Lower speeds, necessitated by 15-cycle
and direct-current work, compel a com-
promise of the efficiency and the mechan-
ical structure of the two elements.

Through improvements in design and
manufacture, large reduction gears have
become feasible, thus interpolating be-
tween the most desirable speeds of the
turbine and generator, respectively. How-
ever, direct-coupled generating units of
about 300 kilowatts and under are be-
ing suitably fitted to the needs of ex-
citation sets and corresponding direct-
current service where low amperage ob-
tains and high economy is not essential.

Centrifugal boiler-feed pumps for
plants of about 2000 boiler horsepower,
ranging in size from 15 to 100 brake
horsepower, establish another class
wherein direct connection of the turbine
proves commercially practical.

The wisdom of immediately coupling
the turbine to large direct-current gen-
erators and centrifugal pumps, screw
propellers in marine practice and other
slow-speed applications has now been
fairly decided by the successful large
flexible gear, giving rise to unrestricted
latitude in design of the component parts
with respect to each other.

A single-reduction gear, or else a train
of gears, has also brought the rolling-
mill requirements within the bounds of
the steam turbine.

An obstacle in early turbine construc-
tion was the involved cylinder design
which militated against uniformity in ex-
pansion and contraction of the parts. This
was unrelentingly assailed by adversaries
of the reaction type and was really pro-
ductive of occasional blade trouble, the
reason for which was very plain in the
study of the old line of turbines. While
the explanation is very simple in its re-
trospect, it obviously required this ordeal
in its commercial development stage to
bring it to the point of success which
it has now attained. Early difficulties
were due principally to the equalizer
ports and supports being cast integral
with the cylinder in all important sizes,
producing variation in the depth of metal
at different points, thus causing the cyl-
inder to slightly camber with tempera-
ture changes. This trouble has been
eliminated in all improved designs by
separating these exterior parts from the
cylinder proper. As this practice has
now been in effect for three years, there
has been ample experience in the opera-
tion of a great many units of this ad-
vanced construction* to prove its merits.

Evidently there were cases in the early
days of numerous blade mishaps from
contact due to the distortion above noted.
Also different qualities of blades have
been employed until a successful compo-
sition and quality were secured. Steel-
and copper-clad blades, which were used
in certain stages of turbine history, soon
gave out where the steam possessed any
corrosive properties. However, a great
many turbines so equipped have not

*Hff pRppr hpfnrf V'naJnoi*rn Hoc\piy of
Wpslorn IVninvlvanla an'l llio I'lltKlnirK Rail
wny r'liiti.

shown any perceptible signs of blade de-
terioration after several years' constant
operation where the boiler feed was un-
contaminated. A case in point occurs
right here in South Bend, where a 1500-
kilowatt Parsons turbine having steel
blades has just been opened up and found
in excellent condition after four years'
constant service.

Heavy blade and disk construction
may, to the lay mind, be construed as
prima facie evidence of strength and
rigidity, but any attempt to unduly rein-
force its construction may defeat the end
in view.

No abnormal strains should be intro-
duced in the turbine in changing from
condensing to noncondensing operation
and vice versa. Should the outer rim of
a disk be more quickly lowered in tem-
perature in converting to condensing ser-
vice, the plate may buckle, thus render-
ing the unit not only unserviceable but
unsafe.

If the feed water is chemically active,
it is important that the design freely
allow lining the cylinder because of wall
corrosion.

Inherent Characteristics of Types

The elementary distinction between
"impulse" and "reaction" design is that
the former employ high relative velocities
across the blades with equal pressure on
either side of the rotating buckets, where-
as in reaction blading low relative veloc-
ities obtain and a drop in pressure — or,
in other words, expansion — also pro-
gresses in the blades themselves, which
really constitute small nozzles.

Use of low velocities entails the least
abrasive action of blade surfaces from
steam jets, the wear being some function
of the square of the relative steam speeds.
The effect becomes more serious in the
presence of moisture and provides a
logical reason for establishing reaction
blading in all low-pressure stages. To
offset the effect of high-velocity moist
steam in the impulse type, increased
superheating is being recommended to
delay the occurrence of saturation, or the
dew point, to the last stage -in other
terms, to insure dry steam throughout
the expansion. This naturally requires
more costly boiler outlay and piping sys-
tems with the attending liability of greater
maintenance expense. A gain may be
derived from the viewpoint of repairs,
but not in the sense of fuel economy.
Prominent European builders of impulse
turbines in taking cognizance of these
facts largely subdivide the low-pressure
stages to attain low steam velocities.

Since in the reaction type the greater
part of the work is performed as the
steam issues from the blades, the neces-
sity of a sharp and well preserved en-
trance angle is of comparatively little
moment. But in the impulse type the
greater part of the dynamic energy in
the steam jet is exerted on entering the

538

POWER

October 3, 1911

buckets, so that it is very necessary that
Uie blades and direction of the jet be
correctly maintained. Thus it is manifest
that the reaction turbine will show greater
permanency as regards efficiency, either
in case of slight wear or scale deposits
on the blades.

Unequal pressure on the sides of the
rotating blades in the reaction type
creates an end thrust which must be
properly counterbalanced. Large capa-
cities induced the development of the
now well known double-flow turbine
which not only solved the balancing
problem but enabled the use of higher
rotative speeds and provided large blade
areas in the final stages, both factors of
economy. Although the impulse type
does not ordinarily experience any un-
balancing of pressures on either side of
the disks, an accumulation of foreign
matter upon the buckets may restrict the
steam sufficiently and produce a consider-
able force in an axial direction, due to
resulting impact. Being without means
for counteracting heavy unbalancing, the
thrust bearing may become dangerously
overloaded. More advantages accrue from
the use of a great many small blades
in reaction turbines than are at first
apparent. An accidental collision of the
rotating and stationary elements may only
result at the most in stripping a small
number of blades, but even under this
slightly crippled condition it may be
safely continued in service, a practice
generally prohibitive with the disk type
with heavy blades and thin shafts due to
the lurking danger of vibration from an
unbalanced rotor.

There is a misleading idea that one
type of turbine may be designed for a
greater degree of efficiency when high
vacuums are used, but it is a fact that no
actual difference exists, as may be easily
demonstrated graphically. However, the
change in economy of any particular
type with change in vacuum will depend
to some extent upon the number of
stages or rows of blades which it con-
tains; therefore, the turbine of fewer
rows or stages is more sensitive to
changes under operating conditions and
will more rapidly decline in efficiency if
the auxiliary equipment is not maintained
up to the original standard. Besides,
the striving and expense warranted in
maintaining high vacuums is plainly de-
batable when the greater auxiliary power
and investment are fully reckoned. It is
simply an economic problem which in
reality settles itself in any particular in-
stallation.

Regulation and Operating Qualities

Stability in operation is essential in
all power stations, large and small.
Swinging of load between various units
may, if not corrected, become so ag-
gravated as to impair or jeopardize the
service rendered by the plant. While
v.'ide regulation from no load to full load

is preferred in the parallel operation of
alternators, it does not relieve the gov-
erning mechanism from the duty of
promptly responding to load changes. To
effect smooth regulation and obviate the
tendencies to race and hunt, the "fly-ball"
regulator must be sufficiently powerful
to overcome any momentary sticking or
binding, and the inertia and friction of
rest without hesitancy. In hydraulically
operated valves, the relayed action of
the governor should not be retarded
through the necessity of accelerating the
long columns of oil communicating be-
tween the pilot valve and the operating
cylinders.

Simplicity in valve and governor mech-
anism is paramount to insure instant
action at any critical moment. Gradual
steam admission has the advantage of a
smooth regulation curve, and the gover-
nor must control but a single valve.
Where each step in valve operation- repre-
sents, say, 300 horsepower, the sluggish
action or sticking of any one valve may
bring about unfortunate results.

The governor or regulator should be
supplied by forced lubrication and in-
cased for the safety of the operatives.

When in service, the turbine should re-
quire a minimum of attention under any
and all variations in load. It has largely
scored over the reciprocating engine in
the matter of small attendance.

In large stations chiefly, and in other
plants where the loads remain very uni-
form for long periods or change gradual-
ly, these features may not assume such
importance as indicated. But, allowing
that the swings on the station are of an
appreciable amplitude, as occurs with
interurban-railway loads and in industrial
plants having rolls, bulldozers, elevators
and similar intermittently operating ap-
paratus, sensitive regulation is demanded
where office lighting is furnished from
the same source of current.

Efficiencies

Scarcely any reference to the compara-
tive economics of the reciprocating en-
gine and the turbine need be made; their
relationship is already well established.
In strictly condensing service the tur-
bine, as previously noted, is more effi-
cient, excepting perhaps in the smaller
units. For noncondensing work the en-
gine may show a somewhat higher heat
efficiency, but it is often the reverse when
final capital economy is considered.

There is much to be said, however,
regarding the performance characteristics
of different turbines. Various builds could
not be expected to coincide in the re-
sults they produce for important reasons,
since blading formation and proportions
are the governing factors. The superior
efficiency of nozzles over buckets has
been thoroughly settled; hence turbines
employing the reaction principle, being
all constituted of nozzles, should surpass
other types by from 5 to 15 per cent.,

notwithstanding radial leakages. Accord-
ing to all records, this type has developed
the best results thus far obtained. The
proper measure of turbine performance
is the efficiency ratio or Rankine cycle
efficiency; that is, the ratio of the equiva-
lent energy transformed into effective
work to the heat energy actually avail-
able. Water rates alone do not exhibit
the true economy of the turbine, as low
steam consumption may be obtained by
sacrificing the other station equipment.

Ratings

Within the last three years a new
reference for rating generating units and
other electrical power apparatus has
come into use to a limited extent. This
has taken the form of basing the full-load
capacity on the greatest amount of power
which may be delivered by the machine
continuously without dangerous heating
or strains or seriously falling off in
speed. The capacity thus determined is
termed a "maximum rating." Previously,
t'ne more conservative practice provided
all important machinery of this class with
a continuous marginal overload of 25
per cent., which was distinguished as
the "normal rating." Each method of
rating is to be respectively indorsed un-
der appropriate circumstances. Only
where there is definite knowledge that
the unit will not be compelled to operate
constantly at some greater capacity than
fixed upon should maximum ratings be
employed. This removes the conservatism
so essential in important service and
should therefore be confined to special
cases.

Turbines rated on a maximum basis
are incapable of carrying full load should
the vacuum be accidentally lost, which
might embarrass the operation of the
plant. Boilers possess sufficient over-
load capacity to provide the increased
steam required to run the turbine non-
condensing, and the boiler plant should
not be rated at its maximum output as
a higher efficiency obtains at a lower
rating.

For the different ratings the design of
the turbine would not be necessarily
changed to produce better light-load
economy for the normal rated turbine as
no advantage would accrue even with a
swinging load. It would mean, though,
in the maximum rated turbine that all
the power possible was being forced from
the same frame used for the machine
when normally rated at lower capacity.

The unit cost per kilowatt of a maxi-
mum rated turbine is necessarily lower
than the normal rated machine, while it
may be identical in every respect. De-
lusions of this nature have frequently
caused real misapprehensions.

An allowance for system power factors
is also very important, its neglect in
many plants having very unfortunately
resulted in burning out the generator and
disabling the unit.

October 3, 1911

P O W E R

New power House Equipment

Gelser Automatic Check
\'alve

The Gelser automatic water-gage check
valve is designed to shut off the steam
and water the instant the gage glass
breaks. It consists of an outer casing in
which there is a plunger valve and a
shaft for resetting the valve after the
glass has been replaced.

The plunger valve is pivotally mounted
as shown in the illustrations, and is so
located that its ball nose is directly op-

Fic. 1. Ready for Service

posite the tapered opening in the tubular
stem, which is screwed into the wall of
the regulator. The tapering inlet hole
increases the velocity and so directs the
discharging steam and water against the
back of the plunger valve, the instant
the gage glass breaks, that the latter is
instantly forced shut to its seat. In Fig.
1 the valve is shown ready for service.
Under normal operating conditions the
pressure is equal on both sides of the
plunger valve. When the gage glass
breaks, the full boiler pressure is directed
against the pocket in the plunger valve

Banks Gate \^alve

The accompanying illustrations show
a new type of gate valve of the double-
disk, internal-wedge parallel-seat type.
This valve is designed for exposed line

ccck and then the other. In case the
plunger valve should stick after auto-
matically closing, it may easily be opened

Closed Position

and forces this valve closed to its seat.
Instantly shutting off the steam and water,
as shown in Fig. 2.

The check valves are cleaned of sedi-
ment by blowing off with first one drain

^-^

^

MMMi-]

l^nl

■r

^// M^

~~A

■^ ^^ ■

f

Fic. 3. Ready for Resetting

and reset by turning it into position ready
for service with the operating shaft, as
shown in Fig. 3.

Fir,. 4.

Device Attached to Feed-water
Regulator

A side elevation of the check valve
attached to a feed-water regulator is
shown in Fig. 4. This device is manu-
factured by the Long Grate Bar Com-
panv. Buffalo, N. Y.

Banks Gate Valve

work. The chief advantage lies in the
accessibility of the inside moving parts,
all of which may be removed through the
opening created by the removal of the
bottom cap on the rising-stem type by
rotating the handwheel until the spindle
is disengaged from the threaded collar.
Renewals of any worn or broken internal
parts are thus easily effected and the
valve is out of commission but a very
short time if a new body ring is needed.
The opening in the bottom of the body
is brought up close to the flange of the
ring, so that a special wrench can be
easily inserted in the port opening of
the ring, and by means of three small
lugs cast on the ring, it is easily re-
moved.

540

POWER

October 3, 1911

The wedging surfaces are placed on
the inside of the disks to prevent any
wear from the flow of the vapor or liquid
passing through the port openings. The
casting of the body and bonnet in one
piece is made feasible by providing an
opening in the bottom of the body proper,
and it tends to greater strength in the
casting and the general construction.

This valve is suitable for use with
superheated steam, as the casing, cap
and disks arc of steel, and the body
rings, disk rings, spindle and spreader
of inonel metal. On the brass valves
the cap is screwed in place, no bolts
being used. This valve is the invention
of Frederick R. Banks, Paterson, N. J.

Pasadena Municipal Lighting
Plant

In the annual report of the Pasadena,
Cal., municipal lighting plant, recently
filed by City Auditor Kellog, it is stated
that the plant, established at a preliminary
cost of about $200,000 and now valued
at $500,000, has, with a 5-cent lighting
rate furnished revenues of 8110,900.71
to the city for the fiscal year ending July
30, 1911. Of this amount $70,268.20
represents the sale of commercial power,
and $40,632.51 as saved by the city for
street-lighting and public building ser-
vice.

During the past year $71,631 has been
expended in extensions to the system.
Within the next two years, the present
valuation is estimated to increase 50 per
cent., or to $750,0(K), by proposed addi-
tions to the plant and distributing lines.

Water Rights in Washington

When the dam across the mouth of
Rock lake, in Whitman county, Cal., was
planned by the Palouse Irrigation and
Power Company, of Palouse, to provide a
storage reservoir of approximately G600
acres for use during the summer season,
property owners in the district brought
legal action to enjoin its construction.
They claimed that it would prevent the
flow of flood waters which annually sub-
merged their lands, and renewed the soil
with a rich silt. They were granted an
injunction in the lower court, which was
sustained by the State Supreme Court in
the following decision:

"A riparian owner has the right to the
natural flow of the waters in their natural
and accustomed channels, without diminu-
tion or alteration, subject only to the
same right and use in every other
riparian owner. Water may not be
gathered into reservoirs for the future
use, when it may best suit the conveni-
ence of one riparian owner, and thus de-
prive other riparian owners of their use
and service of the stream in its natural
condition, unless such right is exercised
under a valid prior appropriation. This

court has always recognized the doctrine
of prior appropriation of water on public
lands, as superior to all other claims,
while it has also recognized the com-
mon law right of the prior owner against
all but bona fide prior appropriations."

Polytechnic In.stitute Lectures
on Power Plant Design

Fifteen lectures on "Power-plant De-
sign" will be delivered during the even-
ing technical courses of the Polytechnic
Institute, by George A. Orrok, the con-
sulting professor of power engineering
at the institute and mechanical engineer
of the New York Edison Company.

These lectures will be given every
Monday evening, commencing October 2,
at 7:30 o'clock, and will include the fol-
lowing topics: Results obtained and re-
strictions governing power-plant design,
ratings, centers of load, distribution,
types of industrial power plants, archi-
tecture; boilers, materials and construc-
tion; furnaces, grates and stokers; chim-
neys; fuels and ash-handling devices;
valves, pumps, heaters and meters; steam
piping, engines and auxiliaries, con-
densers, indicators; estimates, specifica-
tions and power-plant operation.

Sale of Rogue River Electric
Company

One of the largest transfers of prop-
erty in Oregon took place when the
Rogue River Electric Company, of Med-
ford, was purchased by the Siskiyou
Electric Power and Light Company, of
Yreka, Cal., for $3,300,000. The pur-
chasers come into control of power plants
and a lighting and power system which
covers the Rogue River valley territory,
together with a hydroelectric power plant
now under construction on the Rogue
river, near Prospect, which is estimated
to cost $800,000.

The Siskiyou Electric Light and Power
Company, of which J. W. Churchill is
president, owns the Oregon properties
of the Ashland Power and Light and the
Klamath Power companies. With its
recent purchase, the company's power
plants now have a generating capacity of
about 80,000 horsepower, at low water,
tied in with a transmission system of
800 miles.

Large California Power
Project

Permission having been granted to daiu
the Colorado river, work has commenced
on one of the largest power and irriga-
tion projects yet attempted in the South-
west. The initial dam will be constructed
at the Bullhead site in Pyramid canon,
about 40 miles north of Needles, Cal.
It will be of the "arch dam" type, con-
structed of reinforced concrete, about 140
feet high and 400 feet wide, and will

'form a lake approximately eight miles
wide, with an average depth of 100 feet.
This lake will be used to irrigate the
Chuckwalla valley and Palo Verde Mesa,
120 miles distant.

Electric energy is to be developed from
the impounded waters, and power plants
of many thousand horsepower will be in-
stalled. A series of electrically operated
pumping stations will be erected at eight-
mile intervals to lift the water in a dis-
tance of 27 miles, 300 feet above the
river bed into an irrigation system formed
of distributing canals, thus providing suf-
ficient volume to reclaim nearly 300,000
acres of land.

Power will also be furnished to vari-
ous mining interests in this section, and
an extensive system of transmission lines
is planned. The work will be done on
the unit plan, each item as completed
being placed in operation. About five
years will be needed to accomplish the
entire project.

The Chuckwalla Development Com-
pany, BIythe, Cal., of which R. M. Teague,
San Dimas. Cal., is president, has in-
augurated this enterprise and several
million dollars will be spent to complete

BOOKS RECEIVED

The Soil Soll'Tion. By Frank K. Came-
ron. The Chemical Publishing Com-
pany. Easton, Penn. One hundred
and thirty-six pages. 5;'ix9 inches;
tables. Price, $1.25.

Testing of Engines, Boilers and Au.xil-
lARY Machinery. By W. W. F. Pul-
len. The Scientific Publishing Com-
pany, Manchester, England. Seven
hundred and twenty-one pages, 5'4X
8' J inches; 733 illustrations. Price,
12s. 6d.

PERSONAL

At 202 Equitable building, Boston,
Mass., the Oil City Boiler Works, of Oil
City, Penn., has opened headquarters for
looking after the sale of Geary water-
tube boilers in the New England States.
George P. Flinn has been placed in
charge.

Peter Eyermann, known to our readers
through various contributions, largely up-
on gas-engine subjects, and situated at
Witkowitz Mahren, Austria, has been ap-
pointed to read a paper on American
blast furnaces, steel works and rolling-
mill equipment before the Austrian So-
ciety of Mechanical Engineers and Archi-
tects in Vienna. He will be very much
pleased to receive at the above address
photographs, prints, descriptions, etc.,
which would be useful in this connection,
especially those showing the use of blast-
furnace gas under steam boilers, and
those descriptive of blowing and roll-
ing-mill engines.

\o\. .U

M-:W YORK. OeTOBKR In, l^^l

\n.

• '"P^ID it ever occur to you, Ed, what a mass of
IJ information and instruction there is bound
u\) in a copy of Power?"

"Xow that you mention it, no. But I do know
that it is a big nickel's wortli of reading for anyone
in our line."

"As an experiment, I sat down the other night to
read my paper in a scientific way. \A'e have been
hearing a lot about scientific this and scientific that,
and I decided I'd try a little science in my way of
reading. I picked up a copy of the latest issue (Octo-
ber 3) and as I idly glanced at the cover, wondering just
what would be the most scientific way to start my
reading, my eye fell on the words, ' Outline of Tojiics
on page 74,' printed on the cover. I had never noticed
it before and. thinks I: 'Your Incle Bill is not so well
acquainted with his paper as he thought he was.
I must look to see how long this thing has been going
on.' Looking through the back numbers, I found
September 19 was the first issue.

"I turned to the 'Topics' page in the issue I was
going to read and found a table of all the titles in
the magazine and a neat note of explanation for each
big article.

"'This is all right,' thinks I; 'here is the place to
begin to get scientific' I skimmed over the titles and
checked off four articles to read first, as these seemed
'm be most worth my lime. Of course, I always read
'he 'Readers with Something to Say' department,
(Questions before the Hcmse ' and the ' Inquiries of
General Interest' page. These three are bread and
butter to me, being, as I am, a man on the job.

"My idea of scientific reading is to read first every-
thing that is important to me. Then, if I have any
time left over, I read the stuff not f|uite so vital.

"I get a lot of fun out of reading the 'Inquiries'
page like this: I cover the answer with a slij) of paper,
read the f|ucstion and then try to answer it myst-lf.
Then, I compare my answer with the printed aiiswer.

Sometimes my guess is a th()u>und miles off the right
track.

" In the part for readers «-ith something to say,
the idea about an engine-room log book is a mighty
fine one, although it isn't verj^ new. If more engi-
neers would keep such books it would be better for
them. The letter about running a Corliss with only
one steam valve is ver)- interesting. The cause of
Mr. Hyde's trouble with corrosion seems to be bailing,
as does Jlr. James' case of erosion. There seems to
be verA' little generally kno^-n about these two fonns
of destruction. Mr. Dickson is rather rough on the
fellows he calls scrub engineers, although I guess there
is lots of ground for his complaint.

"The most important general article I checked off
was 'Centrifugal Pump Capacity and Speed.' When
I first looked at this article it seemed rather fonnidable
on account of all the fancy-looking formulas it has.
But, after I bit into it, so to speak, I found nothing
to stump me at all. The article is along good practical
lines and just what men like you and me need occa-
.sifmally. I know more now about centrifugal pum]is
than I ever did and if I happen to need a new piunp
some time, I'll have some sane ideas to work with and
I'll be able to put my hand on the rule for finding the
capacity or speed in no time, for I filed that article
with my other engineering literature.

" What I liked particularly about the article was the
fact that in the mathematical work the nile was stated
first, then the formula was given and finally an actual
example in figures was worked out. Xow. any man
who understands arithmetic at all ought to be able
tf> use those formulas after that.

"As it is getting a bit late now T wr.n't make v»ur
car sore by talking to you any more I'll simply ■^ay
that after getting through with the more important
articles I started to read the others and found that,
although they were sometimes a bit out of my line,
and in spots over my head, they were inlerestinj;, in
'i|)ite of this, and served to increase niv general store
t'S knf)wledge."

P O W E R

October 10. 1911

A Light, Heat, Power and Ice Plant

The Lee Electric Light Company, in
Clarinda, la., operates a small combined
light, heat, power, refrigerating and
water-pumping plant which is interesting
in many respects. Clarinda is a going
little town of 4000 inhabitants, typical
of the West.

By virtue of the variety of service
which the plant performs, its load factor
is exceptionally high. In the summer
time, when the ice business is good, the
lighting load is less than in the other
seasons when little artificial ice is needed.
The water-supply system includes a
standpipe which is filled by the pumps
of the plant; thus the pumps may be
run at almost any period of the day
which is best suited to conditions.

During the heating season practically
all of the exhaust steam is sent uptown
and sold to the company's numerous
customers.

The present equipment of the plant
consists of the following:

Buildings

The power-plant building is of brick
60x100 feet, of which 40x60 feet is boiler
room and the remainder, 60x60 feet, is
engine room, of which 20x40 feet is re-
served for future equipment but is at
present occupied by the company's office.
The basement of this building contains
the feed pumps, exhaust-steam sep-
arators and the return tanks of the
steam-heating system, also a quantity of
steam, water, air, oil and ammonia pip-
ing, electric conduits, etc.

The ice-making and cold-storage build-
ing is of concrete construction for the
first story with hard red brick and hollow
building tile for the two upper stories.
This building is 52x140 feet. There are
30 feet of vacant ground between the
two buildings, but the two are connected
by a concrete tunnel in which are racks
for all the piping and conduits leading
from one building to the other. There
is also an inclosed passageway above
ground. About two-thirds of the build-
ing are taken up by cold-storage rooms;
the walls, ceilings and floors of all rooms
are insulated part with two layers of 2-
inch nonpareil cork and part with two
layers of 2-inch xylolith ; the sharp freezer
has two layers of 3-inch nonpareil cork;
all insulation is plastered with Portland
cement. Direct expansion in 2-inch pipe
coils is used throughout. The tempera-
tures held are from five degrees below
zero up according to the goods stored.
The remaining one-third of the building
is occupied by a 240-can ice-freezing
tank using 300-pound cans, an electric
store room and shop, pipe shop and fit-
ting racks, and a barn for four ice-de-
livery teams, etc.

By J. O. Olson

^4 small central station
containing Corliss engine-
driven generators and ice
machines. Light, heat,
poiver , ice and water are sup-
plied to Clarinda, a typical
Western town in Iowa.
Because of the variety of
service furnished, the load
factor is exceptionally high.

'Sul.mittfd to the Institute of Opei-atiny
Knffineors as thesis to (jualify for degree of
Mastei- Operating Engineei-.

Boilers

There are four 60x1 6- foot return-
tubular boilers equipped with Jones un-
derfeed stokers.

All four boilers are set side by side
in one battery. A 36-inch smokebox or
breeching extends across all four up-
takes and connects with two 36-inch by

for the ammonia compressors. These
are all of the simple noncondensing type.
One is 16x30 inches in size and of the
heavy rolling-mill design, direct con-
nected to a 150-kilowatt, two-phase, 60-
cycle, 2200-volt revolving-field. National
Electric Company generator running at
120 revolutions per minute. One is 16x
36 inches in size and of the same type
but belted by rope drive to a 100-kilowatt,
two-phase, 60-cycle, 200-volt, revolving-
field Warren Electric Company induction-
type generator, running at 600 revolutions
per minute while the engine speed is 80
revolutions per minute.

The other two engines are 12x30
inches, and 12x24 inches in size and of
the girder- frame type. These engines
are each direct connected to a 1 0*4 x 17-
inch Wolf-Linde ammonia compressor
rated at 30 tons each when running at
77 revolutions per minute.

A small high-speed engine 5x6 inches
in size and of the American Blower Com-
pany's make, drives the fan and the
stoker mechanism. The speed of this
engine is governed by the steam pres-
sure. The governor consists of a dia-

1. Cold-storage Building in Fork
Right

iNE House to the

100-foot steel stacks, one at each end of
the breeching. Dampers in the smoke-
box are so arranged that either stack
can be cut out or both may be used at
once, or one for each two boilers. The
pressure carried is 115 pounds (gagel
and seldom varies as much as 5 pounds.
The fuel used is mostly slack, very low
in heat value. No trouble is experienced
in burning it. however, and the stacks
are for the greater part of the time al-
most smokeless.

Engines

There are four Murray Corliss engines.
two for the electric generators and two

phragm valve so connected that it will
close as the pressure increases and open
as the pressure decreases; thus the speed
of the engine and stoker equipment in-
creases inversely as the steam pressure.
This arrangement is quite sensitive and
and results in a ver>' steady steam pres-
sure.

Pumps
The feed pumps are three in number,
one 8 and 5 by 12-inch outside center
packed Burnham pump; one 5^1 and 3
by 6-inch duplex Canton pump; one 5'j
and 3' J by 6-inch March pump. There
is also a small March pump for the oil-
ing svstem.

Octobsr ID. 1911

P O W E R

543

The water supply for the plant is fur-
nished by two Cooks deep-well steam
pumps. The steam cylinders of these
pumps are 10x36 inches, having 6-inch
working barrels about 60 feet below the
pump heads.

leave the power station and form a com-
plete circuit around the business square.
One 5-inch main is run in the opposite
direction into the residential district, sup-
plying both sides of the street for four
blocks. This main has no return pipe,

Fic. 2. The Boiler Equipment

Thereare also three motor-driven Go"Ids
deep-well pumps located about a mile
from the plant. These are used for city
water pumping only. These pumps have
24-inch strokes and 6-inch working bar-
rels down about 50 feet below the work-
ing heads. There is also one pump of
the same type which is doing railroad
pumping. The city water system is of
the standpipe type and the railroad has
a large supply tank, consequently we are
enabled to do most of the pumping dur-
ing the hours^when the other load is the

J h test.

The water for the plant itself is used
to advantage step by step. It leaves the
wells at a temperature of about 54 de-
grees and is sent through the double-
pipe ammonia condensers. This, of course,
raises its temperature some 10 to 15
degrees. What water the plant does not
need itself is sold to the city; the re-
mainder is run over the steam condensers
which make the distilled water for ice
manufacturing. The condensing water
now is about 1.50 degrees and goes tn
the Baragwanath open feed-water healer
from which it leaves at a temperature
close to 212 degrees, besides having got
rid of many of its impurities and much
■cale-forming matter.

Stf.a.m Hf.atino

The steam heating amounts to about
35.000 square feet of radiation. Two fl-
inch mains and two 2' '-inch returns

the st,;am traps discharging through con-
densation meters to the sewers, the
charge for heat being based on the num-
ber of pounds of steam condensed. The
heating supplied in the business district

and feed pumps in the station basement.
This water has a temperature of about
165 degrees and as it is perfectly free
from any scale-forming matter it makes
a good boiler feed. Part of it is used for
tilling ice cans as considerable ice is
made during the heating season. This
makes it possible to send the exhaust
from the ice machines also uptown for
heating. It also results in quite a saving
in well water as the atmospheric con-
densers for the making of distilled water
are cut out altogether. Finally, it saves
boiler-feed water and boiler compound.

The pressure carried in the heating is
from atmospheric up to 3'j pounds, ac-
cording to the weather and the demand
for steam. AH engines and auxiliaries
have their exhaust piping so arranged
that any one, or as many as necessary,
can exhaust either to the heating system
or to the atmosphere through the ex-
haust feed-water heater or to the at-
mospheric condenser for distilling water;
thus no engine need work unnecessarily
against back pressure. In case the ex-
haust is not sufficient to keep up a pre-
detennined pressure, live steam is auto-
matically supplied through a very sensi-
tive regulator. A back-pressure valve
is provided which acts as a safety valve
against overpressure.

The heating mains and returns are all
insulated with Wyckoff wood lagging. All
pipe lines are carefully graded and given
as much pitch or fall as possible so as
to drain perfectly at all times and under
any pressure. This point the writer has
always considered as being very im-
portant in order to prevent waterhamnier,
to reduce back pressure on the engines

Fir,. ^ ThI- niHFfT-rOMNKCTFI) I'nIT ^N^ Tlir Sw IT( lllloVRn

is charged for mnstiv on a basis of the and to get the full capacitv of the pipe

number of square feet of radiation served, lines with as low a pressure as possible.

In this case the customer's steam traps Expansion is another factor in connection

discharge into the return main and the with the heating and return mains as well

water returns by gravity to the receivers as with the branches that calls for close

544

POWER

October 10, 1911

attention. Wherever possible, the expan-
sion is taken care of by long sweep
bends. But on long straight lines slip
joints are installed and in a few cases
swing joints are used. The greater part
of the system has been in operation seven
years, and has. as yet, not had a leak,
break or rupture in any underground pipe.

Svi ITCHBOARD

The switchboard consists of six marble
panels as follows: One exciter and regu-
lator panel, two generator panels and one
panel for incandescent lighting, one for
power and one for arc lighting. This
board has all of the latest equipment,

such as integrating and indicating watt-
meters on the generator panels, besides
the regular voltmeters, ammeters, etc.
The exciter panel carries the Tirrill
regulator, the synchroscope, ammeters,
voltmeters, switches, rheostat wheels, etc.,
for the two exciters.

The back of the board has two sets of
l-.usbars arranged for either running
parallel or independent; all high-tension
current is handled through oil switches,
all circuits are equipped with automatic
circuit-breakers, all wires come and leave
the board in iron conduits, and no high-
tension current appears on the front side
of the board.

Electric power is supplied to practically
every power user in Clarinda. An eight-
mile line to supply light and power to
another town (New Market) is now under
construction, and the prospects are that
several other small towns and villages ia
the neighborhood will be supplied in the
near future. This plant was not all built
in a day, but has had a steady growth
from the start. The writer is at present
making plans for a new generating unit
and an additional switchboard, a sub-
merged coal-storage and coal-handling
equipment, additional cold-storage rooms,
and auxiliary equipment incidental to
these installations.

Boiler Efficiency of 83.69 Per Cent.

The Southern Pacific Railroad recently
put its Fruitvale, Cal.. power station into
sen'ice. This station furnishes current
to the company's electrified suburban
lines which run between Oakland and
the numerous suburbs of that city and
San Francisco. The plant is laid out
according to the latest approved practice,
and high economy might naturally be ex-
pected of it.

The possibilities of the station for de-
veloping current economically are sug-
gested in the following abstract of the
report of two boiler tests which were re-
cently conducted under the direction and
supervision of R. F. Chevalier, consulting
engineer and specialist in steam power-
plant economy.

The object of the tests was to deter-
mine the efficiency of the boiler under
normal load. The first test was made in
compliance with a guarantee clause in
the contract between the manufacturer
and the purchaser, and as the indicated
efficiency was so high it seemed advisable
to check it by conducting another test.
The second test was conducted in the
presence of Prof. W. F. Durand, of Le-
land Stanford University, and W. C.
Miller, engineer of power stations for
the Southern Pacific company.

The boiler tested is a Parker water-
tube, rated by the builders at 645 horse-
power and designated as a compound
three-pass tj'pe. It contains 280 four-
inch tubes, 17 of which are 20 feet, 6
inches long. 17 are 22 feet, 6 inches long
and the balance 20 feet; two steam and
water drums, 54 inches in diameter and
22 feet long, and one superheated steam
drum 18 inches in diameter and 20 feet
long.

The superheater originally consisted
of 40 loops of I'J-inch tubes and con-
tained K34.4 square feet of surface; later,
this was cut down to 107.5 square feet
by the removal of eight loops.

The steam and water drums are divided
by a horizontal steel diaphragm riveted
to the shell and extending from the

Description of luv tests
made of a Parker boiler at
the Fruitvale station of the
Southern Pacific Company
which indicated efficiencies
of 83.69 and 83. 1 7 per cent.

Oil iL'as used as fuel.

rear head to within a short distance of
the front head. To the front end of this
diaphragm and to the lower part of the
drum is riveted a vertical steel plate
forming a pocket at the front to collect
the scale discharged from the tubes and
dividing the drum into two separate

chambers. In this plate is a manhole
having a hinged cover on the inside wnich
when closed makes a water-tight joint.
The pivot on which this cover swings is
at the top of the manhole and the weight
of the door keeps it closed under normal
conditions. This swinging manhole plate
acts as a nonreturn or antipriming valve.
Its function is to allow the water dis-
charged into the upper compartment to en-
ter the lower compartment of the drum but
to prevent the return of any water to the
former. The upper section in the drum
is known as the steam space, the lower
as the water space. The bottom of the
drum below the level of the nipples
leading to the tubes forms the sediment
paa or mud drum. An inverted angle
iron with closed ends is placed over the

1. Sectionm \'ik\\. Showing Design of Boiler Tested

October 10, 191 1

POWER

545

blowoM opening, thus making the blow-off
effective over a considerable area.

The tubes are divided into three banks,
each bank forming a pass. The upper
bank is known as the feed element and

>r,-ifti^-rS^^j s ^rnvTrS-rt^rv-^"

Pic. 2. Plan and Section of Furnace

'■i as an economizer through which the
cd water must pass before entering the
urns. The intermediate and lower
nks are termed steaming elements. The
nk of tubes comprising the economizer
20 tubes wide by 4 tubes high, and is
the third pass of the gases. This
nank is divided into two parts, each 10
• ibes wide by 4 tubes high, each of these
irts* discharging into the drum above,
c feed water enters the front end of
.,it first tube in each of these parts,
which are the upper wing tubes. At the
rear of each of these tubes a connection
is made betwee* the junction box and
the respective drums with an expanded
nipple. In the junction box is placed a
nonreturn valve which prevents the feed
from goiiig the wrong way and entering
the drum through the inlet connection.
The flow in the economizer elements is
forward and backward alternately through
the tubes in the top row, then down to the
next row, and so on, finally discharging
through two vertical upcasts into the rear
head of the drum above the diaphragm.
The water then flows along the diaphragm
into the front pocket, through the swing-
ing manhole and into the lower or water
chamber of the drum, whence it flows
by gravity to the steaming elements.
If the feed Is shut off. the drum connec-
tion furnishes the economizer elements
with water.

The intermediate bank of tubes is in
the second pass of the gases and is com-
posed of rive elements, four tubes wide
and four tubes high. The water from
the drum enters these elements on the
upper or induction end through a down-
cast ti'be which is expanded in an inlet
hov '''inplyinc two elements. Fach ele-
ment has a nonreturn valve in the inlet
box which prevents the reversal of the
flow of water. The water in these ele-
ments passes four times across, thence
down to the next row. and so on through
the remaininc tubes to the lower end of
each element which is connected to the
steam chamber by an independent up-
east discharging info the steam space of
the dri'm.

The lower bank of tubes consists of
10 elements, two tubes wide and six high.
The tubes in these elements, with the
exception of the lower row which are in
the furnace, form the first pass. The
upper ends of the elements are con-
nected to the drums by means of down-
cast tubes and inlet boxes in the same
manner as before mentioned. The water

cubic feet. Three burners, equally
spaced across the width and with the
tips extending 2 inches into the furnace,
enter through the boiler front. In front
of each burner a rectangular area on the

JUJf

1^^

Fig. 3. Design of Fuel-oil Burner Used

entering these elements passes across
two tubes, thence down and across two
tubes, and so on to the last tube,
whence it is discharged into the drum
through an independent vertical upcast.

Furnace

The furnace is of the ordinary type,
having grate bars such as are used for

Fic. 4. Arrangement for Measuring
Steam to Burners

grate bars. 37 inches wide by 42 inches
long, was left uncovered. On this area
were placed soap firebrick, laid in loosely
and arranged so as to allow the admission
of air for combustion through small
openings running crosswise to the di-
rection of the flame. A large rectangular
opening was left beneath each burner.
The ashpit is subdivided into three com-
partments, each of which supplies air to
the individual setting for each of the
burners. For arrangement and details
see Fig. 2.

An internal mixing type of burner,
manufactured by P. ]. Owens and illus-
trated in Fig. 3. was used.

Fig. 5. \j,

Sami'Lino Tubl

burning coal; the hridgcwall has been The apparatus for wcighinc the feed

left out. The furnace is 10 feet wide by wafer consisted of two pairs of platform

If! feet R inches long, with an average scales placed upon a staging. On these

hight of 4 feet between the tubes and the scales were placed the tanks in which

furnace floor, making a volume of 666 the water was weighed. After being

546

POWER

October 10, 1911

weighed the water was emptied into a re-
ceiving tank beneath, from which it was
delivered to the boiler by a special pump.
A hook gage was placed in the receiving
tank and at the beginning of the test the
tank was filled so that the point of the
hook just broke the surface of the water
and at the end of each hour the water
lever was brought to this point. The
water in the boiler was maintained at
as near a fixed level as possible. The
outlets from the blowoffs were discon-
nected and blanked. The outlets from the
water column and gage glasses were
carefully watched; no leakage occurred
from either. At the end of each hour
the actual amount of water used was
checked. . The scales were standardized
by representatives of the manufacturer.

The apparatus for handling and weigh-
ing the fuel oil consisted of a standard-
ized platform scale placed upon the same
staging that carried the scales for weigh-
ing the water, and upon this scale a tank
into which the oil was pumped as re-
quired. From this tank the oil, after be-
ing weighed, was run by gravity into a
receiving tank beneath, from which it was
taken by a pump, passed through a heater
and thence to the burners. The oil pump
was fitted with a governor and an auto-
matic relief valve. Thus, a constant pres-
sure was maintained in the oil line to
the burners. The discharge from the
relief valve led back to the tank from
which the supply to the pump was taken.
As the oil was emptied from the weighing
tank a small sample was collected four
times each hour. The samples thus col-
lected represented a fair average of the
quality of oil used.

At the completion of the test of January
5, the samples of oil were thoroughly
mixed and divided into four portions, and
placed in small tin containers and sealed.
One sample was delivered to the South-
ern Pacific company, whose chemist
made an analysis; one was used in Mr.
Chevalier's laboratory for analysis and
the other two were placed in storage for
future reference if necessary. The re-
sults of the analysis by the Southern
Pacific company's chemist showed a
lower heat value than that determined by
Mr. Chevalier. For the test of March
18. a sample was sent to Prof. Edmund
O'Neil, dean of the department of chem-
istry of the University of California,
Berkeley, for determining the heat value
and water contained in the oil. As the
results obtained by Mr. Chevalier were
confirmed by those of Professor O'Neil
they only are given in detail in the pres-
ent report. A Parr calorimeter w'as used
by Mr. Chevalier in determining the heat
value. Two determinations were made
on each sample and the results aver-
aged. The water contained in the oil
was determined by distillation, and the
specific gravity was determined with a
Westptial balance.

Steam Used by Burners
The steam supplied to the burner was
measured during the test of March 18.
The method of measuring this steam is
as follows; A diaphragm with an orifice
0.5 inch in area was placed in the steam-
supply line. On either side of the dia-
phragm holes were drilled and tapped for
two '4 -inch pipes, these pipes being

amount of such steam being determined
by condensation and weighing. The
amount of steam used by the burners
was found to be 4.16 per cent, of the
total water evaporated.

All of the thermometers, gages and
scales used in the tests were calibrated
and proper corrections were made in the
final computations.

liE.'^ll.TS OF EV.\POU.^TIVE TESTiS ON A 645-HOR.SE POWER PARKER BOILER AT
IlilTTVAI.E POWER STATION

■ 'I'

u-f te
ion I
■ of humer .

1 ype

MaKe of burner.

NiimbtT of burners u.-iett

Water-heating surface, square feet

.-Superheating surface, square feet

.\VEK.\GE PrES-SURES;

Barometer, inches of mercury

Steam pressure b.v gage (saturated), lbs. persquare inch.

Oil pressure at burner, pounds per square inch

Force of draft in flue after damper, inches water

Force of draft between damper and boiler, inches water.
Force of draft in furnace near superheater, inches water.
Force of draft in ashpit, inches water

.AvER.\r,E Te.mperatures, Degrees Fahrenheit:

E.\ternal air .•

Fire room

.\ir entering ashpit

I'urnace (6 feet from bnrner tip)

(jases entering first pass

tiases leaving first pass and entering second

Ua-ses leaving second pass and entering third"

Clases leaving third pass and entering fourth

Gases escaping from boiler

Oil at burner

Feed water entering boiler

.Superheated steam

.-Saturated steam due to pressure

Degrees of superheat

F>'El.:

ICind

ilravit.v of oil at 60 degrees F., specific

(Iravit.v of oil at 60 degrees Fahrenheit, degrees Beaume.

Percentage of water in the oil

Calorific value of dr.v oil per pound, B.t.u

Weight of oil as fired , lbs

Weight of oil consumed corrected for moisture, lbs

X'olume of moisture-free oil consumed, bbls

Fi-i

.\VERAGE PER Hoi'R:

( )il consumed per hour as fired, pounds

< )ii consumed per hour corrected for moisture, pounds ....

N'olume of dry oil consumed per hour, barrels

oil per hour "corrected for moisture per cubic toot of furnace

volume, pounds

I )il per hour corrected for moisture per square toot of heating

surface, pounds

\V.\TER:

Total weight fed to boiler, pounds

Factor of evaporation

llfiuivaient evaporation from and at 212 degrees, pounds.

W.\TER, Average per Hour:

Water evaporated per hour

Fquivalent evaporation from and at 212 degrees, pounds. .
ICciuivalent evaporation from and at 212 degrees per square

foot of water heatiiiK surface, pounds

Horsepower develoi'cil. A.S.M.E. rating .,

iiuilders' rated hor-.ipowi-r

Percentage of builders' rating developed

KcoN'OMic Results:
Water evaporated under actual conditions per pound of oil as

lired , pounds

ICq iivalent evaporation from and at 212 degrees per pound of

(111 as fired, pounds

l-MUnalent evaporation from ami at 212 degrees per pound of

ml corrected for moisture, pounds

EFFiriEN'rv;
F.lficieney of the boiler, per cent

.VXAI.YSIS OF THE Dry Gases bv Voldme:

t'arbon dioxide (CO,), per cent

Percentage of excess air al>ove amount theoretically required

.Ian. .i. 1911

March IS. 1911

8

10

interna

I mi.ter

Ow

ens

S

3

6,-157

6.457

i:!4.4

107.5

30.4

30.1

178.5

179.7

78

92

0.31

0.294

0.165

0.15

-1-0.01

+ 0 016

0 02

0.02

610
400
3S4
128
165
539
379
160

690

420

394

113

123.4

561.2

379.5

181.7

crude oil
0.9700
14 43
1.2
18,513
11,841
11,699
34 . 5

crude oil
0.9627
15.37
0.6
1S.6.S1
14,093
14,008
41. 56

1,480
1.462
4.31

1^09
1,401
4.15

2.195

2. 1 ■

0.226

0.21T

156,974

1.19
1S6,79'J

180,240 •

1.244
224.2 IS

19,621
23,3.W

18,024
22.422

3.62
676.7

3 4Y

630

15.775

1.-. 91

15.967

16 01

83.69

S3 17

13.11.')

13 -.

connected to the legs of a manometer
filled with mercury. In the steam pipe,
ahead of the diaphragm, was placed a
pressure gage and beyond the diaphragm
a thermometer w-as inserted to determine
the temperature of the steam. The ar-
rangement of this apparatus is shown in
Fig. 4. After the test the orifice was cali-
brated by passing steam through under
a series of observed conditions, the

To determine the amount of airenter-
ing the furnace, an analysis of the gases
of combustion for carbon dioxide was
made by the use of the standard form
of Orsat apparatus. Samples were taken
where the gases leave the first pass and
enter the second. The sampling tube was
inserted at L, Fig. 5.

The following obser\'ations were taken
every 15 minutes: Steam, oil and draft

October 10, 1911

P O W' E R

547

pressures; temperature of the super-
heated steam, steam to burners, feed
water, fuel oil, boiler room, air entering
ashpit and escaping gases. The tempera-
ture of the furnace and that of the gases
passing through the boiler were taken
every 10 minutes. For determining the
:i:rnace temperature, a Fery radiation
r rometer was used. The temperature
of the gases through the boiler w-as taken
with a Bristol electric pyrometer, several
couples being used and placed at points
where the gases left one pass to enter
another. The positions of these couples
are shown in Fig. 5.

The fires for the first test, January 5,
were lit on the evening of the fourth
and the boiler was maintained in a stand-
by condition throughout the night. At 8
a.m., January 5, steam was drawn from
the boiler so that the fires might be
burned at normal intensity. The test was
started at 9 a.m. and continued until 5
p.m. During the test, the fires were
tended by a regular fireman, who ad-
justed them according to instructions.
The draft regulation was attended to by
.Mr. Chevalier. The boiler had been in
operation since November 30, 1910.
Prior to the test, the water had . been

drained from the boiler and the internal
surfaces inspected. In the lower and in-
termediate steaming elements there was
no deposit of scale, but in the feed-
water element a slight scale was found,
the thickness of which was about 1 32
inch. Both drums had a soft, slushy
mud covering the bottom about 6 inches
deep for its full length. This mud was
removed and the drums washed. None
of the tubes was cleaned internally. The
soot was thoroughly blown from the heat-
ing surface on January 4.

Test of March 18, 1911

In the interval between January 5 and
March 18, the boiler had been operated
intermittently at about one-half of its
rating. Prior to the test, the. boiler was
opened and the tubes in the feed-water
element were scraped; the tubes in the
intermediate and lower elements required
no cleaning.

Fires were started under the boiler
on the evening of March 16 and moderate
fires were maintained through the night.
A test was made on March 17, but owing
to the irregularity of the load on the
boiler it was deemed advisable to make
another test on the following day. Light

fires were again kept under the boiler
during the night. At 9 a.m., on March
18, steam was drawn from the boiler so
that the fires could be burned at normal
intensity. The test was started at 10 a.m.
and continued until 8 p.m. At 1 :33 p.m.
a strainer in the steam line to the oil
pump filled with scale from the steam
pipe, necessitating a shutdown of three
minutes until the strainer could be taken
out. The fires had to be extinguished,
but the flow of steam from the. boiler was
not interrupted, thus causing a drop in
the pressure. The soot had been blown
from the tubes on March 16, and thus
the boiler had been operated for about
30 hours before the time of the test with-
out further removal of soot.

Although the heating surface of the
superheater had been decreased, the de-
gree of superheat was more in this test
than in that of January 5. This was due
to the fact that the opening through the
baffles between the furnace and the first
pass had been shortened, causing a
greater volume of the gases to sweep
over the heating surface of the super-
heater. In all the tests conducted, no
blisters or signs of distress appeared on
arv of the tubes.

Engine and Machinery Foundations

The first and most important purpose
for which foundations are employed is
to insure that any settlement which oc-
curs will be uniform; the second is to
• vide an anchorage. This last purpose
be accomplished in combination with
first, but an anchorage is only nec-
•iry where the energy developed in
machine is not absorbed or utilized
::; a direct-driven machine, as in the
i.ase where the power is taken off by or
delivered to the machine by belts or
ropes. Anchorage is also required by re
tirrocating machines which are improp-
balanced or in which the direction
notion is reversed abruptly, the mass
•he foundation serving to absorb and
pen vibration. There are some classes
machines which can be safely set
■;iout either foundations or holding-
■ n bolts, as rotar>' converters and
^^o-generators or similar combinations
unted upon rigid bedplates. The only
uirement in these cas-is is that the
: porting structure shall have sufficient
Jity and be capable of meeting tne
centrated loadings imposed,
'•"ock bottom is most desirable where
rs supporting heavy machinery are to
rut in. but it may introduce complica-
• s in getting rid of vibration. Rock
a tendency to transmit shocks or
rations to all surrounding structures
•ing upon the same bed, and where
re is any chance of vibration a bed
Jry sand from 6 to 12 inches thick

By A. E. Dixon

Iliil yoik makes the Ih'sf
natural foundation. Dry
sand or gravel comes next.
(Juieksand. ulien in thick
beds, requires failing. Piles
should be cut off hcloic the
leater line and capped icith
concrete. Direct-con nected
machinery docs not need as
massive joundations as
other typc\.

must be placed between the rock and the
foundation. This sand bed can be made
within a pocket excavated in the rock
or. where a flat bed exists without natural
retaining walls, by building a pocket of
concrete to hold the sand in place. Min-
eral wool and felt cushions have been
utilized under light foundations, but they
do not possess the lasting qualities of
sand.

There are many different grades of
rock and the natural bed if the stone
may be at any angle between the hori-
zontal and the vertical. The most favor-
able conditions arc those in which the

rock has a horizontal bed and does not
disintegrate upon exposure to atmospheiMC
influences. Some rock is called "rotten"
because it deteriorates and softens upon
exposure, while in other cases beds of
rock are found which upon, their first ex-
posure are soft enough to excavate with
a pick and shovel but harden rapidly
and must be blasted after exposure.
Alany other outcrops require blasting,
while in still other cases the natural
cleavage permits its removal with wedges;
in some of the softer rocks this method
of breaking up into derrick or one-man
or two-man sizes is less expensive than
Mock-holing and using powder.

The safe loading upon rock depends
entirely upon its nature, and ranges from
5 to 200 tons per square fool. In cities
having building codes the safe-load limi-
tations of the natural soils found within
their limits are specified. Where there is
no building code the safe loadings can be
qnvcrned by the values given in Baker's
"Masonry Construction." This table has
been widely copied and may be found in
many handbooks.

Sand or gravel, particularly when dry
and well drained, is next to rock in de-
sirability, and in some respects is the
best substratum. It is easy to excavate,
and if free from clay and loam the ex-
cavated material can be utilized in mak-
ing mortar or concrete, thus reducing the
expense of masonry construction. Other
soils have to be removed and used for

548

POWER

October 10, 1911

grading low places or back filling, and
the disposal of the surplus soil may
considerably increase the expense of ex-
cavating.

Mud, soft alluvial soil, quicksand, etc.,
often make foundation work difficult, par-
ticularly where heavy concentrated loads
are to be carried. Piling or raft founda-
tions then become necessary. Where the
water level is permanent, wooden piles
cut off below this level will endure as
long as the structure above them.

There are two methods of capping a
wood-pile foundation. One is to excavate
between the piles for a depth of 2 feet
or a trifle more; then fill in around the
piles to a depth of a foot with clean sand
and upon this a bed of concrete is laid.
The depth of this concrete over the heads
of the piles will depend upon conditions
and the load. An interesting example of
concrete mat over piles is found in the
foundations of the Long Island City
power plant of the Pennsylvania Rail-
road. This mat is 6 feet 6 inches thick
at all points except under the four stacks,
where it is 2 feet thicker. The site of
this foundation is inclosed within sheet
piling. In this case the thickness of the
mat was partly dictated by the tidal con-
ditions of the East river, on which the
plant is located. The floor of the power-
house basement had to be above high
water while the piles had to be cut off
below low water. Sheet piling is neces-
sary in building foundations of this kind
in order to prevent the earth about the
excavation from caving in, and to prevent
damage to adjacent structures. It also
serves to limit the quantity of water flow-
ing into the excavation and reduces the
expense of keeping the pit dry. Where
the surrounding soil is subaqueous, cof-
ferdams constructed of sheet piling or
cribwork are required.

The earliest method of capping a pile
foundation consisted of laying heavy
squared timbers on top of the piles to
which they were secured by drift bolts.
On top of these and at right angles to
them another layer of squared timbers
was laid. These two layers were usually
of 12xl2-inch material. The interstices
between the timbers were then filled with
sand, gravel or concrete and a flooring of
6x6-inch timbers was laid over the area.
These timbers were solidly drift-bolted
together and upon the surface thus pre-
pared was laid the stone or concrete
masonry for the foundation. This method
was very expensive as the piles had to
be cut off low enough to keep all of
the timber work below the water line.

There are a number of formulas for
determining the bearing power of piles.
Most of these depend upon the distance
the pile sinks under the last few blows of
the pile-driver drop. These are very poor
ways of determining how much the pile
will sustain, though they are widely used
by engineers who should know better.
The writer has seen a pile sink 3 feet and

more under one blow of the hammer and
then come up nearly the same distance
as soon as the hammer was lifted off
its head. Holding this pile down with a
heavy weight for a short time resulted in
its becoming so firmly fixed in position
that repeated blows with the hammer
could not drive the pile down '4 inch;
when the endeavor was made to pull the
pile the heaviest tackle available could
not stir it. The use of formulas based
.upon the distance the pile sinks under
one blow has often resulted in driving
the piles down into themselves until they
split and lost strength.

Quicksand, when it reaches a consider-
able depth, can be overcome by driving
piles down to the firm underlying stratum.
Thin layers can be removed by placing
sheet piling around the area lo be ex-
cavated; inflow will also be prevented by
this means, as this is t'le main trouble
in such cases.

Medium beds occasionally present
themselves. The writer once put in a
heavy foundation for a twin reversing
engine with 55x60-inch cylinders driving
a 34-inch blooming mill, the entire area
of which was underlaid by a bed of.
quicksand about 12 feet thick. The meth-
od adopted in this instance was to drive
two rows of sheet piling about 3 feet
apart, inclosing the area for the founda-
tion. The space between the sheet piles
was then excavated, the piles being held
in position by heavy bracing. This ex-
cavation was carried down 2 feet into
the firm layer of hard pan underlying the
quicksand and then filled with concrete,
this forming a concrete cofferdam around
the foundation area. The space inclosed
was then excavated to the required depth,
which left 10 feet of quicksand below
the foundation. This sand was so fluid
that a man could not stand in it unless
supported by a plank. The surface of
the quicksand was then covered with two
layers of tar paper at right angles to
each other and a thin layer of concrete
was deposited on the tar paper; then a
2-foot layer of concrete was deposited
to form the foundation footing. This
method of doing the work saved nearly
1000 cubic yards of concrete, and the
foundation proved all that could be de-
sired. No appreciable settlenient had
occurred when the elevations were
checked up by a bench mark after the
machinery had been operated several
years.

The holding-down bolts in these founda-
tions were from 1 to 3 inches in diam-
eter and from 4 feet 5 inches to 16 feet
in length, 241 bolts being required for
the engine, mill, tables and shear. Tem-
plets, made from drawings, were made
in sections to locate these bolts and
all holes were laid out by measurements
from center lines, a hole being bored
in the templet for every bolt. The templets
locating the heavy bolts were so sup-
ported on a scaffold that their lower sur-

faces were slightly above the elevation
of the top of the foundation. A transit
was used to line up the templet and
after it had been accurately located it
was nailed fast to the supporting scaf-
fold. In the meantime the bolt pockets
in the lower part of the foundation were
brought up to the level for the founda-
tion washers. These washers were set
in- position and located by plumbing down
from the templet.

Sheet-steel galvanized-iron tubes 5
inches in diameter were provided for the
3-inch bolts and 4-inch pipes for the 2-
inch bolts. The blocks turned to fit these
pipes had been nailed to the under sur-
face of the templet for holding the tops
of these pipes in place. These tubes were
then placed in position and their lower
ends were built in with brick laid on tcp
of the foundation washers. In setting
these tubes care was used to get them
centrally located with reference to th,;
bolt holes in the washers and templet.
.After the tubes had been set the location
of the templet was carefully checked.

The smaller and lighter bolts were lo-
cated by hanging them in the templets,
which were so built and supported that
this could be done. Old 3-inch boiler
tubes were rescued from the scrap pile,
cut into 2-foot lengths and used to pro-
vide adjustment space at the top of the
bolts. Newspapers were employed to
center the bolts in the tubes and to pre-
vent the concrete from rising in them.

This foundation was brought up and
finished about I'i inches below the bot-
tom of the bedplates. After the bed-
plates had been placed, lined up and
leveled, the bolts were sufficiently set up
to hold them in position, care being taken
to avoid springing. The tubes around the
bolts were then filled with fine dry sand
to within a short distance of the top of
the foundation. A dam was next built
around each bedplate and the space be-
low it with the tops of the tubes was
filled with grout. Steel wedges made
from 2x'j-inch flat iron drawn down to
a point under a steam hammer were
used to raise the bedplate, the finished
wedge being about 6 inches long, .\fter
the grout had set, the steel wedges were
knocked out and the holes left were filled
with pointing mortar. An ample supply
of these steel wedges and 3x1 -inch steel
blocks for use as fillers below the wedges
is a great convenience, especially when
lining up heavy machinery. Hardwood,
maple or oak wedges can be used with
light machinery, but they are useless in
working with machines having bedplates
weighing from 40 to 50 tons.

Direct-connected sets, such as steam
turbines and generators, motor-generator
sets, rotary converters or well balanced
reciprocating engines with generators can
be mounted on structural foundations.
Care, however, is necessary in the case
of reciprocating units to insure that their
cyclical period of vibration does not co-

October 10. 1911

POWER

549

incide with that of the supporting struc-
ture or is not a harmonic of it. When
these cyclical periods harmonize the en-
tire structure will be thrown into vibra-
tion. Should this occur the first remedy
to be tried is slight alterations in the
speed of the machine. A bucket of water
should be set on the floor close to the
machine and the vibration ripples on the
water will show the effect of the changes
in the speed. When it is impossible to
cure the trouble in this manner, additions
can be made to the weight of the ma-
chine by filling in the hollow portions of
the bedplate with cement concrete. If
enough weight cannot be thus added, a
platform can be suspended under the
machine in the floor below and a founda-
tion built on it. The rods or bolts carry-
ing this dead weight should be threaded
to permit their load being clamped up
solidly against the ceiling below the ma-
chine.

When properly constructed, a rein-
forced-concrete structure furnishes a
favorable foundation. It is rigid and
heavy and thoroughly tied together.
Structural steel framing with concrete
floor slabs makes the next best arrange-
ment, particularly if care is taken to tie
the steel frame with portal and "X"
bracing. Tile or tile and concrete floors

its reason for being in the position as-
signed and no liberties can be taken
without endangermg the structure. Once
there was a country millwright who read
in the daily papers about reinforced con-
cretes and saw some wonderful pictures
of rei.iforced-concrete dams. It fell to
his lot to build a small dam for , the local
authorities and it was decided to use re-
inforced concrete. So this millwright
bought all the old horseshoes and scrap
from the local blacksmith and mixed the
mess with sand, cement and gravel and
placed it in the forms. The life of this
dam was very brief; in fact, it collapsed
as soon as the forms were taken partly
down, but, fortunately, before any amount
of water had accumulated. Steel scrap
mixed in the concrete does not act as
reinforcing, and it is not wise to attempt
a reinforced-concrete structure \Vithout
competent advice.

Coal Haiullinir at iMuncie
Electric lAght Plant

Bv F. O. Whiting

In the American Gas and Electric Com-
pany's plant at Muncie. Ind., is installed
a complete system for handling coal from
the railroad cars to the stokers and for

COAL-HANDLINC EQUIPMENT AT MllNCIE Pi ANT

arc not as good as heavy slab conslruc-
'■ in The design of this type of founda-
<ihould not be lightly undertaken, as
not a case where "most anything
Jo" and an improper design will re-
in trouble, perhaps a serious disaster.
Tuctural reinforced concrete, some-
- called steel concrete, is not the
•M aeelomer.;tion it is sometimes im-
cd to be. Every piece of steel has

discharging the ashes from the furnaces.
The railroad cars containing coal are run
into the yard under a 70- foot span, open-
girder type of crane operated on an ele-
vated track approximately 70 feet from
the top of the crane rail to the ground.
This is shown in the illustration. The crane
is equipped with a man-operated trolley
from which is suspended a grab bucket
having a capacity of S4 cubic feet, or

about 1 'A tons, and traveling at a speed
of 250 feet per minute. By means of this
machinery the coal is delivered from the
cars at the rate of about 60 tons per
hour either to the ground storage or
to a traveling crusher located upon the
roof of the boiler house. Here it is
crushed and delivered into the overhead
bunkers in the boiler house to be fed to
the stokers at the will of the fireman.

The bucket is of the four-rope type,
using two ropes for closing the bucket
and the other two for closing and lower-
ing it. The operating mechanism for the
bucket in the trolley is arranged so that
the bucket is hung directly from three
drums, the two holding ropes being fast-
ened to the center drum and the two clos-
ing ropes to the outside drums. The
closing drums are geared direct to a 50-
horsepower series crane motor and the
holding drum is geared to another motor
of the same type and size, thus provid-
ing two motors entirely independent of
each other for the manipulation of the
bucket. These motors are fitted with
solenoid-operated brakes and are con-
trolled by means of a magnetic switcn-
control panel operated by a master con-
iroller which also operates the brakes and
is arranged to give the following opera-
tions of the bucket:

One point of power on the closing
motor with the brake released on the
holding motor to allow the bucket to sink
into the coal while closing.

Four points of power with both brakes
released to hoist the loaded bucket, the
two motors equalizing under the strain of
the loaded bucket.

One off position with both brakes set
for holding the loaded bucket while the
crane or trolley is traveling.

One kickoff point with the holding
brake set for dumping the bucket.

Four points on the dynamic brake for
lowering the empty bucket.

As all the operations of the bucket
are entirely controlled from one master
controller, the operator has only three
controller handles to manipulate when
operating the crane; these are: the buck-
et controller handle, the trolley controller
handle and the bridge controller handle.

The weight of the trolley complete with
the loaded bucket is approximately 25,-
000 pounds and it is driven along the
bridge by a 10-horsepower series crane
motor. The traveling crane is propelled
in either direction at a speed of 300 feet
per minute by a 25-horsepowcr series
motor. This motor is fitted with a solenoid
brake for bringing the crane to rest, also
for holding it against the effect of
weather conditions.

The bridge and trollev controllers arc
fitted with a special point nn cither side
of the off position, which cuts off the
power from the motor without releasing
the solenoid brakes and allows the crane
to drift before coming to rest.

550

POWER

October 10, 191 1

The coal is delivered to the plant in
the run-of-mine size, and a Jeffrey sin-
gle-roll crusher reduces it to stoker size.
This crusher is mounted on a steel frame-
work placed on four 12-inch double-
flanged truck wheels which run on a track
the full length of the boiler house. It is
equipped with a receiving hopper hold-
ing about three bucketloads of coal and
is belt connected to a 20-horsepower
shunt motor. The coal is delivered
through openings in the roof to the over-
head bunkers in the boiler house and

the crusher is then moved along the track
by placing the grab bucket alongside the
hopper and moving the traveling crane in
the desired direction.

The plant has a capacity of approxi-
mately 3200 boiler horsepower, being
equipped with eight Stirling boilers of
100 horsepower each; these are fitted
with chain-grate stokers. The capacity of
the overhead bunkers is approximately
500 tons of coal.

Under each grate are two hoppers;
that under the forward end being the re-

claiming hopper, which is used to catch
the unburned coal falling through the
grate and which is fed again to the
stokers. The ashes are dumped over the
rear end of the grate into the ash hopper
where the contents are discharged into
small dump cars which carry them out
of the building through an underground
passage to a concrete ash hopper lo-
cated in such a position that the ashes
can be reclaimed by the bucket and dis-
charged into railroad cars for shipment
bv rail.

The Steam Turbine in Germany

Since the fuel economy of steam tur-
bines has reached a figure which will not
be greatly surpassed in the near future,
the attention of designers has been di-
vested to increasing the output or ca-
pacity in order to effect economies in
floor space, weight, construction, attend-
ance and other items, the aggregate of
which is superior in importance even to
the fuel consumption. It is interesting
in this connection to note that the capac-
ity of Allgemeine Elektricitats Gesell-
schaft turbines has increased between
IP04 and 1911. for the 3000-revoIution
type, from 1250 to 4400 kilowatts; for
the l.=^00-revolution type from .^000 to
11,800 kilowatts; for the 1000-revolution
type from 5000 to 21,400 kilowatts per
unit. The 20,000-kiIowatt unit is the
largest built on the European continent
todav.

Such an increase has been made possi-
ble by a corresponding increase in ojj-
erating reliability of steam turbines. To
■install a 20,000-kilowatt unit as the sole
source of power in an industrial estab-
lishment or central station without any
provision for reser\'e — except such as is
offered by connection to an overland
line — would be impossible if the proba-
bility of breakdown was not now almost
entirely eliminated. Much of the earlier
trouble was due to a lack of understand-
ing of the relative merits and qualities of
materials employed in the different parts
of the turbine and condenser. Other
troubles were due to unclean steam, to
pooi foundations, to unreliable auxil-
iaries, etc. As to some of these prob-
lems, O. Lasche, chief engineer of the
steam-turbine department of the Allge-
meine Elektricitats Gesellschaft, of Ber-
lin, has just communicated the results
of his experience to the Verein deiitscher
Ingenieure for publication, and the fol-
lowing is an extract from his views.

Blade Material

The material emploved for blades in
the first stage which has to deal with
high pressures and temperatures is for
the most part nickel steel. The tem-
peratures and blade lengths occurring in
the following stages permit the employ-

By F. E. Junge

Increased reliahiUty of the
si earn turbine. Steel, brass
and bronze as blade ma-
terial, condenser ttibes and
turbine foundations.

meiu ot brass, while the long blades of
the last wheels necessitate the employ-
ment of a special bronze. These three
materials, each used exclusively within
its own temperature range, give together
complete satisfaction for all conditions
under which steam turbines nowadays
have to work; but in order to ascertain

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Special Steel

these respective limits the chemist and
metallurgist had to come to the aid of
the engineer and designer, since the
old methods of testing materials were
no longer sufficient. By far the simplest
of all materials with respect to analysis
and determination of characteristics is
brass. Its use is governed solely by
factors or terms which are well known
or can be ascertained bv easy methods of
test. Its resistance to rupture, relative
elongation, flexibility and hardness in
cold and heated condition, are all known,
so are the results of the impact or drop
test on notched bars. The numerical
values of the various items are graphical-
ly shown in Fig. 1. Brass retains its full
tensile strength up to 200 degrees Centi-
grade (418 degrees Fahrenheiti. The
figures for bronze are considerably higher,
and the behavior of nickel steel, especial-
ly when it contains a low percentage of

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N!ckel5i-eelw!ihZ5FkrCent Nicktl Brass — ,

•iG. 1. Properties of Various Blade Materials

October 10. 1911

POWER

551

nickel, is even superior to that of brass.
The numerical values of the yield point
correspond, approximately, to the above,
while the cur\es for the relative elon-
sation for the different materials and
temperatures intersect at various points.
The determination of the limits within
which elongation is still permissible is
j:reatly facilitated by the results of the
impact test.

Less simple is the correct determina-
tion of the lower and upper limits of
hardness of blade materials. A certain

Fig. 2. Connections to .Avoid Elec-
trolysis

surface hardness is necessary in order to
provide against the erosive action of the
steam. On the other hand, if the mater-
ial is too hard its tendency to fracture
^ecomes so great that it is no longer suit-
able for blades. Especially is this the case
if the hardness of the material is caused
bv cold-drawing of the metal. The fol-
lowing are considered good mean values
for hardness: Brass, 100; bronze, 125;
nickel steel. 150 to 200. The compo-
sition of the brass alloy is 72 copper, 28
zinc, with permissible traces of lead.
This compound metal is emploved suc-
cessfully lip to -100 degrees Fahrenheit
for blades, and for distance pieces and
shrouding up to almost fiOO degrees Fah-
renheit. The limits for blades is set low-
er because there is an additional heating
of the surface through steam friction,
which can hardly be measured. A note-
worthy feature is the capability of re-
sistance of brass to the action of steam
which is chemically impure. Bronze is
used for blades on account of its super-
ior hardness and its high tensile strength.
When the Curtis wheel was first
adopted by the Allgemelne ElektricitSts
Cesellschaft people there was a general
belief prevalent among German manu-
facturers that the high speed of the
Impincirrg steam would quickly destroy
the blades of the first row, but the ad-
vantage of emploving high steam fem-
peratures and yet having low tempera-
ture? in the turbine casing was so great
that the majority of builders have adopt-
ed the combination. Since the limits with-
in which the different blade materials
are preferably used have been ascertained
there has been no more trouble with the
blading, and there are a number of tur-
bines in actual ser\'ice which, after 25.-
000 operating hours, show no sign of In-
creasing st'-am consumption.

A\uch of the former trouble was due to
impurities in the steam. Deposits from
the boiler, driven by the heat into
hard and granular particles of dust,
caused a rapid wear of the sharp inlet
edges or cavities of the blades. These
troubles, of course, never occur in tur-
bine-driven central stations where the
condensate is used for feeding purposes.
It is iust as much in the interest of the
boiler equipment as in the interest of the
life of the turbine to insist upon the use
of pure feed water. If this precaution
is taken there is no fear of any consid-
erable wear of the blading for several
years.

A second method of failure observed
was due to the outer skin of the bronze
blades showing a tendency to jar off at
excessive temperatures, while with nickel
steel and brass this kind of wear never
happened. Therefore, the upper limit of
temperature for the employment of
bronze blades was set at about 400 de-
grees Fahrenheit, though the decomposi-
tion of the material does not actualh be-
Kin until at almost 600 degrees. This is
proved by the fact that the nozzle heads
of Mlgemeine Elektricitats Cesellschaft
turbines, which in manv installations are
exposed to the full steam pressure of 12
atmospheres (176 pounds per square
incht and to temperatures of 300 degrees
Centigrade or 600 degrees Fahrenheit,
are in perfect condition after 25,000 op-
erating hours.

In contrast to brass there are bronzes
of great tenacity and strength, which, on
account of a small admixture of alum-
inum, are subject to chemical reaction
within certain temperature ranges. These
allovs must be avoided in plants where
the feed water contains magnesium
chloride or calcium chloride or ammonia.
Chemical decomposition does not, how-
ever, begin at temperatures of 400 de-
grees Fahrenheit, but rather within the
range of saturation, namely, between 130
and 70 degrees Centigrade (266 and 15S
degrees Fahrenheit), while below this
limit signs of decomposition were not
apparent. Contrary to the destruction
of blade material through high temper-
atures or mechanical effects, the chemi-
cal decomposition of materials is less
marked at those places which are con-
stantly impinged by the steam jet than at
others where the steam adheres to the
solid particles of sediment carried in.

Nickel steel of various compositions has
been employed for high-pressure blades
since 1907. Blade fractures— most of
them in the full cross-section of th»
material- -did occur at parts which were
subject to stress as well as at others
which were not. After some experiment-
ing the Allgemeine Elektricitats Cesell-
schaft has succeeded in finding an alloy
of nickel steel, the composition of which
is not given, which is used for the guide
diaphracms in all pressure stages and at
all temperatures, and has given complete

satisfaction in six years' service. As
blade material a steel with 5 instead of
25 per cent, nickel is being used. A low
percentage of nickel makes a better ma-
terial than a high percentage, especially
when the carbon content of the steel is
low. and a small percentage is sufficient
also to protect the blades against rust-
ing. Summarizing the foregoing, it is
seen that brass occupies by far the fore-
most place as blade material, the limits
of its adoption being fixed by its tensile
strength, which can easily be ascertained
in its cold and heated condition. Above
this range a suitable nickel steel finds its
field of usefulness, while below it a
bronze of great strength gives satisfac-
tion.

Condenser Tubes

The principal condition for continuous
service is a sufficiently soft material. The
occurrence of transverse fractures or
longitudinal cracks is due exclusively to
faulty manufacture and hardness of the
metal. Another cause of destruction of
condenser tubes consists in the decompo-
sition of the tubes from within, whereby
the material is gradually eaten up all
along the inner surface. There remains
a thin film of solid material which cracks
on some occasion. It is peculiar that
those tubes which contain the warm

Fic. 3. Various Metals Placed in Sea
Water

water are more easily affected than those
through which the cold water flows. This
rotting of the whole material is largely
due to the chemical action of the cooling
water, especially if acid mine water is
used or water which contains ammonia.
These harmful effects can at times be
neutralized by adding chemical com-
pounds to the water.

There is a third kind of destruction of
condenser tubes, the cause of which is
not so easily ascertained as in the above
cases. It occurs frequently when sea
water is used in the condenser and ex-
hibits itself in the form of corrosion
utarting from within. This mode of cor-

552

POWER

October 10, 1911

rosion has given rise to the thought that
an alloy which is not quite uniform in
composition contains in itself infinitely
small galvanic elements; but trials made
with various alloys in sea water for a
year have not so far given evidence of
the correctness of this assumption. Like-
wise it was not proved that an addition of
1 or 2 per cent, of tin to the zinc-copper
alloy meant an improvement of the ma-
terial, or that there is an advantage in
providing brass and copper tubes with a
coating of tin. nor, finally, that pure
copper tubes or those consisting of an
alloy of brass with an admixture of 70
per cent, copper were superior to the
same alloy with only 60 per cent, copper.
In power stations which are located
on the seashore, using sea water for the
surface condensers, and which supply
current for electric railways, or in plants
which are situated in the neighborhood
of such roads, there are potential differ-
ences of several volts, due to stray cur-

current passes into the water is destroyed
through this process. In order to avoid
this kind of destruction of condensers it
has become the practice to provide pro-
tecting plates of zinc and aluminum, the
zinc plate forming the electropositive part
of a galvanic element, which is destroyed
through the generation of the electric
current. With this precaution taken, de-
composition of tubes can occur only when
the bottoms of casings or tubes consist
of. an alloy containing a high percentage
of copper. These researches for the
causes of condenser trouble are to be
continued by the Allgemeine Elektricitats
Gesellschaft.

The chief advantages of surface con-
densation, next to superior operating re-
liability, consist in a low demand for
power, and in the regaining of the con-
densate as practically pure feed water
without the purifying devices which are
used with reciprocating engines for sep-
arating the oil. The rapid introduction

Fig. 4. Turbine Foundations — Old and New Methods

rents, measurable between the metallic
bodies of the plant. These currents can
be eliminated by short-circuiting through
a heavy cable, and, if necessary, by con-
necting the condenser with the negative
rail of the road, as shown in Fig. 2. It
is known also that the metals used about
a steam plant, such as aluminum, zinc,
iron, tin, brass and copper, are attacked
by galvanic currents as soon as they are
brought into metallic contact with each
other. These currents flow in the man-
ner shown in Fig. 3 from any one of the
materials named in the above series to
any named later in the list, and back
through the water as indicated in the
sketch. The material from which the

of surface condensers for land work con-
sequent upon the development of the
steam turbine naturally involved new
problems which required some experience
for their solution, but this experience is
now available and there is no fear of new
surprises.

Foundations

With turbines of 20,000 kilowatts capa-
city, having movable parts weighing 50
tons which revolve at high speed, it be-
comes of paramount importance for the
operating reliability of the plant to pro-
vide absolutely rigid foundations. Even
though the revolving masses are nicely
balanced, there may occur vibration at

one point or another of the system when
the foundation is soft or elastic, and when
the fixed masses of the unit do not cor-
respond to the movable ones. Fig. 4
gives a comparison of turbine founda-
tions built on the old and new methods.

The old way was to erect brickwork
pillars, connect them by means of I-
beams on top, and to fill the hollow
spaces between them with a mixture of
cement, sand and stone. This filling,
however, did not always give a satisfac-
tory connection between foundation frame
and beams.

The new way is to erect a heavy
concrete structure, which is solid through-
out, with an arched vault on top, which
serves as a receptacle for the condenser
and as a base for the turbine. This con-
crete foundation, if properly constructed.
is rigid, and affords the best possible
rest for the frame plate. Of course,
changes such as would be necessary if
the plant was to be enlarged are very
difficult to make; and provisions for prob-
able changes should be made when laying
out the plant. But the main thing is that
the frame plate, which in former times
was subject to being bent and brought
out of alinement when tightening the
holding-down bolts, now finds a rigid
base upon which to rest and in turn af-
fords a true base for the various de-
tachable parts of the turbine.

Dr. H. Loebell, in the Chemical Trades
Journal, warns against too hasty con-
demnation of a lubricating oil because of
deposits which occur in the cylinders,
bearings, etc., where it is used. An ex-
amination of the deposit should always
be made before resorting to an exhaustive
examination of the oil. If the deposit
dissolves for the most part in benzole
(or chloroform), a complete examination
of the oil is called for, and in particular
it should be examined 'as to its tendency
to resinify, using Kissling's method. But
if the greater part of the deposit resists
solution by benzole (or chloroform), the
original oil need only be examined at
first as to its constituents insoluble in
benzine. If the original oil is found to
be almost completely soluble in benzine,
there is no sufficient ground for abandon-
ing its use. The probability is that the
deposit has some other origin; in fact,
in some cases it may be found to con-
sist of inorganic matter (largely silica
and silicates) holding, like a sponge,
unethered or partially resinified oil. The
parts of the machine and lubricating
appliances should be cleaned and a fresh
start made. Should a gummy deposit
mostly soluble in benzole result this
time, the original oil calls for investiga-
tion as to its tendency to resinify, using
Kissling's method. A word of warning
is issued as to paying too much atten-
tion to the reports of greasers whose
"palms may have been oiled." — The En-
gineer.

October 10. 1911

POWER

553

Waste of Power in Unalined Shaftins

A poorly hung line-shaft wastes much
more coal than is usually realized.
Many of the best authorities have de-
clared that the greatest waste of power in
the average manufacturing plant is due
directly to the poor alinement and level
of the line shafts. Up to about two or
three years ago there was no practicable
method of determining the exact condi-
tion of the line i>hafts and of making them
correct. Today, however, there is such a
device and hundreds of progressive plants
are cutting down a big item of waste.

In this connection it is surprising to see
how little the executives of a company
know about the power conditions. They
do not go over their line shafts any more
than is absolutely necessary to keep them
up. I have found in any number of in-
stances plants that have not had their
shafts gone over in three years. The
hundreds of tests of the condition of
line shafts in manufacturing plants which
the Kinkead Manufacturing Company has
conducted have opened the eyes of many
factory managers and the experience
gained in this matter should be of inter-
est to all mechanical men.

In a certain large shoe manufacturing
concern it was found that the shafts
were all in a bad state, varying from Z'A
inches out of level, to 1'4 inches out of
line. This was on shafts about 100 feet
long and from 3 7/16, to 1 15 16 inches
diarrieter. It was taking 85 horsepower
to turn the shafts with all belts on
but no work being done on any of the
machines, while it took approximately 125
horsepower on full load, or 68 per cent,
friction load. This shoe company has
three factories within a radius of fifty
miles and it would pay it very handsome-
ly to line up the shafts of the different
plants with a modern appliance. This

Fic;. 1. SAMPLE REPORT OF SHAFT
MISALFNEMENT TE.'<T

Date March Ul. Kill

A'ltlrt-ss Aulmrn, ,V. )

MM

i>f

in

HanK-

er

.\orth-

soiilh-

So.

lliKh

l/v«l

i«»

(•am

I.I

np

wcst

1

31*

■i

.■« u-

3 1)

3

4

' -^I'l 1

h

21 1

A

1 21 1
21 1

7

H

2|

n

in

1 1 1 1

II

• 1 ^

1^

r

1

1.1

,'.

'

u

v

' . '

Thcsr .1 roliimns dnal Thr«<- :« ml

imnn flfal

with Ihf Irvrl of wild Ihr

alitirment

Khan. of !<hari

10 frH hrlim-n hang-

er: 1

By H. Prime Kieffer

Some results of tests to
determine the alinement oj
shafting in various import-
ant mannfacturing estab-
lishnicnts, showing bad con-
ditions prevailing.

Great savings in friction
load effected by rcalinenicnt.

need be done only two or three times a
year at a very small labor cost, and fVie
shafts kept nearly correct.

Another point which is frequently
brought up is the varying floor load and

FIG.

.sa.mple hepout of shaft
.misai.inf",.mf:.\t test

Date Drr. IS. I9n«

MM

I)L

m.

IlaiiR-

North-

South-

No.

HiRh

Level

Ix)w

east

Line

west

1

-'J

t

:^

'$ f

(■

1

B

A

A

c7

A

A

s
'.t

A

A
H

10

II

•

*

its influence on line shafts. A series of
tests was made in one of the largest
manufacturing plants in this country to
determine this effect. The lines were
found to be in very bad condition. The
buildings were of heavy mill construction
and the argument was advanced that the
condition of the shafts was due to the
changing loads, shrinkage of timbers, set-
tling of the building, etc. To prove that
such was not the case, two lines were
put in absolutely correct condition with
the Kinkead device and the hangers fast-
ened very securely. Then the floor loads
above, and especially those around the
floor columns, were all changed both as
to position and weight. Where the shafts
had previously been out of line as much
as l"» inches and out of level as much as
3'/; inches, after rearranging the loads
and waiting thirty days, at no hanger
was the line out as much as ' i inch cither
way. Monthly readings showed that this
condition remained practically the same
and it was but a few moments' work to
change the hanger which was getting out
of line and level. The idea that the bad
alinement nf shafts is due primarily lo

changing conditions in the plant is noth-
ing in the world but a fallacy.

As far as time of doing the work is
concerned, it is remarkably short, so
much so in fact, that it is always neces-
sary to actually conduct some tests
before people will believe that the work
can be done so rapidly. In the case of
a plant in Indianapolis, at five minutes
to twelve the superintendent took an am-
n;eter reading on a 65-foot shaft, and
found that it was requiring just 15 am-
peres at 110 volts to turn the shaft. All
belts were on but no work being done on
the machines. The line shaft was liter-
ally covered with pulleys, clutches, col-
lars, etc., so that it would be almost im-
possible to level this shaft with t-he or-
dinary carpenter's level. Yet in 55
minutes the shaft was put into per-
fect line and level without having re-
moved a belt, and when the shaft was run
for five minutes after one o'clock, it took
just eight amperes continuously on fric-
tion load, or almost 50 per cent, re-
duction immediately. The shaft was not
nearly as bad, as far as line and level
was concerned, as is found in nine out
of ten plants.

In another instance, that of a paper
mill where they were having trouble with
a line shaft placed on concrete piers, the
line being 260 feet long, the shaft was
found to be 3' • inches out of level from
end to end and as much as ]'•< inches
out sideways, with big jumps at each
successive hanger. With all belts and
pulleys on, that shaft was lined and
leveled absolutely true in five hours. This
was in a dark room too, but the work
was made easy by the illuminated targets
employed. The general superintendent
stated that it usually took the men a full
week to get the line in what they thought
was "good shape."

Most managers and other officials will
be especially interested in tests to deter-
mine the exact amount of saving due to
lining and leveling their shafts. It can
be stated specifically that a saving on
each line shaft of from 10 per cent, to
50 per cent, of the friction load which
that line takes can he guaranteed. Of
course, there arc a number nf elements
which govern the amount that the line is
requiring, such as length, diameter of
shafts, distance between hangers and, of
course, the amount that the line is out of
true, as well as how firmly the hangers
are set. As an illustration of the condi-
tions found in the average plant, a few
readings taken at random from over a
thousand are given. Alany companies
are now vitally interested in this matter
of shaft alinement and have regular in-
spectors who attend to it. taking motor
readings at staled intervals and keeping
the line in perfect condition.

POWER

October 10. 1911

Pulley Faces and Belt Speeds
for Medium SpeedMotors

By H. M. Nichols

The accompanying table gives the belt
widths and speeds and the corresponding
pulley-face widths that are usually ern-
ployed for motors running at medium
speeds.

Pl'LLKY F.\CES AND BELT SPEEDS
For Medium Speed Motors

Width

PiiUev

Belt Speed in

Horsepower

Belt

Face

Feet per .Minute

1 to 4

0"

Oi"

2000

■, to 10

.3"

■M/

2500

10 to 15

4"

4i"

2500

15 to 20

.5"

6"

2500 to :iOOIl

20 to 25

6"

7"

:«100

ao to 40

S"

!)"

:iOOO

40 to 50

10"

11"

nooo

50 to 60

12"

IM"

:iOO(i to :i5ii(i

60 to 75

14"

l.")"

:!5()(i

75 to 100

16"

17"

:i500 to 4000

100 to 125

16"

17"

1000

125 to 1.50

IS"

19"

4000 to 4.500

150 to 200

20"

21"

4500

Starting Rotary Converters

from the Direct Current

Side

By Leonard Freed

The starting of rotary converters from
the direct-current side involves certain
difficulties, depending a great deal upon
the inherent characteristics of the ma-
chine itself. To start a converter from
the direct-current side, it must be treated
as a shunt-wound motor; therefore, if
the machine is compound-wound it will
be necessary to short-circuit the series
field winding or else use the equalizer
lead for starting, in order to leave the
series field winding out of circuit. If
the series winding were left in circuit,
the machine would be differentially ex-
cited and the starting current would be
very large, due to the weakening effect
of the series field winding.

The accompanying diagram shows the
connections used for starting a 1000-
kilowatt 600-volt converter in a certain
plant. A special feature of these con-
nections is the single-pole double-throw
field switch S, which is constructed in
such a inanner that one contact cannot be
opened until the other one is closed. The
object in providing this switch is to
obtain full field excitation during the
starting period and to maintain full ex-
citation should the inain circuit-breaker
open. Without this switch, the voltage
drop in the starting resistance would

reduce the field excitation if the field
circuit were connected directly to the di-
rect-current brushes, or, if the field cir-
cuit were connected outside the starting
resistance, the opening of the circuit-
breaker would disconnect the negative
field terminal from the negative brush
and prevent the machine from exciting it-
self. In the latter case the machine
would be left running as an induction
motor, taking a large lagging current at
the alternating-current side. In order to
excite the converter from the busbars in
the ordinary way it was found that the
design of the converter panel and gen-
eral layout of the switchboard would
have to be changed about to prevent the

cut out of the field circuit by means of
the rheostat, and the starting switch R
is closed in the first step, as shown in
the diagram, starting the machine as a
direct-current motor. The starting switch
is closed gradually as the machine speeds
up and when all the resistance is cut out
the main negative switch is closed and the
starting switch R opened wide. When
synchronous speed is indicated, by syn-
chroscope or lamps, the alternating-cur-
rent switches are closed in the usual way.

With the field connections as described,
it is obvious that if the circuit-breaker
or negative switch were opened, the field
circuit would be dependent on the bus-
bars for exciting current and if it hap-
pened that the other machine or ma-
chines had also thrown their circuit-
breakers the field circuit would be dead.
To avoid this, the switch S is closed up-
ward, connecting the negative field ter-
minal directly to the negative commu-
tator brush. Then the positive switch is
closed and the load adjustment made in
the usual way.

A large rotary converter connected to
the transformers while starting on the

Starting Swifch

Connections for Obtaining Full Excitation under All Operating
Conditions

field circuit of the converter from being
broken after the machine was in ser-
vice, by the opening of the circuit-
breaker; hence the arrangement here
shown was adopted.

In starting up, the negative field lead
is connected to the negative busbar by
closing the switch S downward. Then
the equalizer switch is closed, connecting
the positive brush and positive field ter-
minal to the positive busbar and thereby
exciting the field. All resistance is then

direct-current side (the trarhsformer
primaries are not connected to the sup-
ply circuit, of course), takes a consider-
able starting current, owing to the fact
that the converter armature is practically
short-circuited through the secondary
windings of the transformers. In some
cases it is found advisable to disconnect
the secondary transformer leads at start-
ing, by means of switches in the leads.

Varying voltage at the direct-current
busbars sometimes causes trouble in syn-

October 10. 1911

P O ^' E R

555

chronizing. If the voltage changes sud-
denly just as synchronism has been ob-
tained and the operator is in the act of
closing the switch to connect the al-
ternating-current supply circuit, this will
usually change the speed of the converter,
throwing it slightly out of phase and
causing a large rush of current between
the alternating-current and direct-current
sides of the machine, possibly causing
the brushes to flash over. When a stor-
age battery is floated on the busbars, this
condition is avoided and it is an easy
matter to synchronize a converter started
on the direct-current side, because there
Is a steady voltage at the busbars.

CORRESPONDENCE

Quick Repairs on a Pitted
Commutator

Some time ago 1 was employed as elec-
trician for a hydraulic mining plant where
the centrifugal pumps used were driven
by 500-volt direct-current motors. A
large motor (100 horsepowerl became
splashed with water on one occasion and
the results of the splashing were some
not serious looking pits in the mica
strips between the segments of the com-
mutator— pits in which it would have
been possible, perhaps, to put the head
of an ordinar)' pin.

However, as the machine continued to
run, carbon dust from the brushes filled
these pits. This formed a carbon bridge
across the mica from segment to segment.
and in due season the electric current
would travel across this bridge, burn the
bridge behind it. destroy some of the
nearby mica and carbon, and then things
would run along as before. Each time
this happened the pits were increased in
size, and also, as was to have been ex-
pected, the explosions due to a further
accumulation of carbon became rarer but
more destructive. At length the flame
from the arc formed at the time of one
of these explosions became so large that
it would sweep clear around the com-
mutator and establish short-circuits from
brushholder to brushholder. This would
open the 600-ampere circuit-breaker
which took care of that part of the elec-
trical system and profit taking would be
stopped for some minutes. By this time
the pits were considerably enlarged ; they
would have held a cough drop without
impressing an obser\'er that the situation
was at all cramped.

Oiiick repairs were in order, so I de-
cided to go to the nearest town, about
eieht miles away, and tir to get a suit-
able filling for the pits. After some
thought I decided to try to use the same
cement employed by dentists, which con-
sists of a putty made of glacial phosphoric
acid and oxide of zinc. There was a
dentist in the village who proved to be
very willing to help out. He sold me for

a trifle the quantity of the ingredients
needed and also gave me full directions
for mixing and handling.

In preparing to make the repairs, I
first cleaned out the pits to receive the
fillings. Knowing that the centrifugal
force tending to throw out such a mass
of material was very great. I made the
bottoms of the pits larger than the open-
ings. To enlarge the bottoms of the
pits I upset the end of a small piece
of steel rod '« inch in diameter, until it
had a sort of head on it about 3 '16 inch
in diameter, and filed some cutting edges
on this head, making a tool somewhat
like a rose countersink. After hardening
the piece I used it in a common breast
drill to ream out the bottoms of the pits.

Following the dentist's directions. 1
made the putty by pouring the acid on
the pulverized oxide of zinc until the re-
sulting mixture was just soft enough to
be kneaded between the fingers. I packed
this mixture into the pits solidly, leaving
it high enough above the general surface
to permit a good smoothing down with
sandpaper after it had hardened. In
about two hours it had set hard; I then
sandpapered it well and started the ma-
chinery. The motor never gave any more
trouble in the eight months subsequent
to this, which was the length of time dur-
ing which I had it under further observa-
tion, and the fillings never cracked in the
slightest degree; neither did they wear
excessively or appear to do thfc next most
objectionable thing — wear too little and
thereby cause the brushes to jump when
passing over them.

J. O. Barnwell.

Pasadena. Cal.

The iMaiuijitr (jets Some
Experience

The manager of a certain electric-light-
ing plant was long on managing ability
but short on practical electrical experi-
ence. He knew enough about it to wire
up sockets, fan motors, etc., and fre-
quently came down to the station and
spent an hour or two tinkering around at
some such work.

He came into the station one evening
and proudly exhibited to the engineers
a fine new pair of nickel-plated pliers
which he had just purchased, remarking
t^at when it came to pliers he guessed
that none of us had anything on him.
Before leaving, he remarked that he
vapted a socket and a few feet of lamp
cord to wire up another drop light in the
office. The engineer pointed to a drop
hVbt in one corner of the engine room
which was not in use. telling him to cut
if off as far above the socket as he likf-d
and take it along for the purpose. While
this lamp was not in use. it was still
connected to the circuit through a fuse-
less rosette, the cord, of course, being
"alive."

The manager took a chair and started
over to get it. Climbing upon the chair,
he reached up and took hold of the cord
with his new pliers; but instead of sep-
arating the two cords and cutting one
at a time, he cut them both at once.
There was a loud snap, a blinding flash,
and the manager, chair and all came
down onto the floor in a general mix-up.
He got up, eyed his ruined pliers sadly

and remarked: "Well, any d d foo!

that don't know any better than to do a
trick like that ought to get killed any-
how."

Samuel Kirlin.

New York.

Mr. Edge'.s \\'iring Pointers

In his article. "Practical Points on
Electric Wiring." published in the Septem-
ber 12 issue. Mr. Edge seems to ignore
the fire underwriters' requirements. For
example, a snap switch should not con-
trol more than three lamps; further,
the two-light circuits in Figs. 4 and 5 are
shown without any fuses, which would
rot be allowed.

^Smtch

i; 0 0 0 0 0 0 0 0

J J

2J'

<m:m^?ivemi^^;mmi!K^;;.i%

m Switch

m^ 9 (> (> 6 <) o

_w^

315

Fic. 5.

His paragraph on grounding conduit is
rather restricted and vague. There arc
well defined rules for grounding a con-
duit correctly.

E. ROPETER.

Pottsville. Penn.

Bags arc caused by overheating por-
tions of the sheet while under pressure.
Sediment, mud or masses of scale settle
on the sheet, preventing access of water
and the metal, being softened by the heat,
yields to the pressure and stretches into
the form of a pocket or bag It can b:
prevented by keeping the boiler clean.--
F.x.

P O ^' E R

October 10. 1911

L Akl C^ 1 1 I

Sarii;ent COmliiiied Gas En-
jrine and Air Com-
pressor

With the increasing demand for com-
pressed air for industrial purposes and
its economical compression in large or
small quantities, there have been many
improvements and refinements in com-
pressors which have increased their effi-
ciency and reliability, yet the thermal
and volumetric efficiency of many air
compressors is still too low. Moreover,
on account of the high cost of electric
power and low mechanical efficiency of
compressors belted frorn gas engines, air
compression on a small scale is not
feasible in many cases where it would
otherwise be employed. It was with these

Fir,. I. Combination Engine and Com-

I'RKSSOR

conditions in mind that the self-contained
gas engine-air compressor illustrated here-
with was designed. It consists of a
vertical gas engine with a differential
trunk piston, the larger diameter of the
piston being used for compressing air in
the annular space around the smaller
trunk. As there is but one piston
structure, one connecting rod, one crank
and one shaft for both the gas engine
and the compressor, the mechanical effi-
ciency of the unit is naturally high.

On the upstroke, air is drawn into the
crank case through the port K, Fig. 2,
when it registers with a corresponding

port on the crank disk J. On the down-
stroke, air is compressed in the crank
case and flows through the automatic
valve E into the annular chamber around
the trunk of the differentia! piston. On
the return stroke this air is forced through
the automatic outlet valve H and outlet
/ to the storage tank or receiver; during
this stroke the crank case is again filled.
On account of the large surface sur-
rounded by cold water and the short
distance the heat has to travel when gen-
erated in the annular space by compres-
sion, it is said, the thermal efficiency
should be higher than in compressors

riG. 2. Valve Mechanism and Cylinder Construction

October 10. 1911

P O W E R

557

having a small cooling surface per unit
of volume.

.As the pressure is always downward,
a clearance of 1/100 of an inch is said
to be maintained easily, and discharge
pressures of from 60 to 140 pounds, ob-
tained with high volumetric efficiency.
The upper end of the connecting rod is a
large steel ball; therefore the piston and
rings may revolve and produce uniform
wear of the cylinder wall.

The engine works on the four-stroke
cycle and as air is compressed on ever\-
stroke the two flywheels and crank disks
are made heavy in order to maintain a
sufficiently uniform speed. The valve
gear is highly ingenious. A cam L on
the half-time shaft oscillates a rocker
yoke pivoted on the stud G and thereby
opens the inlet and exhaust valves suc-
cessively. When the cam strikes the
roller M, the exhaust valve B is lifted; a
quarter of a revolution later it engages
the roller N and lifts the admission valve
A, a link Z from the valve rod W to a

Fig. 3. Open for Inspection

vertical arm of the rocker yoke holding
the blade Y in the path of the block X.
Should the speed exceed the normal rate,
the inertia weight S will lag behind the
exhaust-valve rod in its downward travel
and pull the blade U to the right where
it can engage the plate V and hold the
exhaust valve open. This also holds the
rocker yoke tilted in such a position that
the link Z pushes the blade Y out of
reach of the block X and prevents the
inlet valve from being opened when the
cam /, engages the roller N. The next
time the cam L engages the roller M,
if the speed has fallen to normal the
governor weight S does not lag behind
the valve rod in falling, and the blade U
misses the plate V. allowing the val.vc
gear to resume normal operation.

Either gas. gasolene or kerosene may
be used for fuel. When gas is used it is
adtnitted through a graduated valve to
the space /? from which it flows to the
explosion chamber with the air when
the supplementary disk Q on the admis-
sion-valve stem rises. Gasolene or kero-

sene is taken in through a mixing valve
on the air pipe, shown in Fig. 1.

Compressed air from the storage tank
filled by the compressor is used for
starting. It is admitted through the valve
C which is positively opened at the be-
ginning of each working stroke as long as
compressed air is turned on and the pres-
sure is greater than that in the combus-
tion chamber. The valve rod d passes
through the end of the stud G, which
serves as a guide for it, and carries at its
lower end a roller e located in the path
of the cam f. When the cam lifts the
rod it merely relieves the spring pres-
sure on the valve stem O, allowing the
air pressure to open the valve if the
internal pressure will permit.

The crank pin is accessible through
the handhole plates, or the piston rod
and crank may be adjusted or removed by
turning back the cylinder on a hinge, as
shown in Fig. 3. Ignition is effected by
jump spark; the primary circuit of the
induction coil is closed once in two revo-
lutions by a pin on the secondary gear.

Compressors of this type will com-
press air to 200 pounds gage or to any
lower pressure at which unloader is set.
This outfit was designed by C. E. Sargent,
136 West Lake street, Chicago. 111.

The Heat Equivalent of the

Conden.sate from a Gas

Calorimeter

By J. .Ai.BKRT Al. Robinson
There are various means of determin-
ing the heat value of the condensate or
drip from a gas calorimeter. The meth-
od herein described is one not commonly

The accompanying table gives the heat
content of 1 to 10 cubic centimeters of
condensate, at temperatures from 35 to
100 degrees. For any other quantity of
condensate than those stated, the heat
content may be found by direct propor-
tion.

Example

For one cubic foot of producer gas
burned in a calorimeter, the average tem-
perature of the exhaust gases was 70
degrees, and the quantity of condensate
was 6 cubic centimeters. The gross or
high heat value of the gas was 136.8
B.t.u. as metered. Required, the net or
low heat value of the gas as metered.

From the table, in the 70-degree line
and in the column under 6 cubic centi-
meters, the heat content of the condensate
is found to be 14.7 B.t.u. Therefore,

136.8 — 14.7 ~ 122.1 B.t.u.
low value, as metered.

Oil Engines for Warship
Propulsion

There is a probability of the British
Admiralty ordering oil engines for a
thorough practical test of their suitability
for warship propulsion, says Engineering
I London I. Several torpedo-boat-building
firms are to submit designs either for a
destroyer to be propelled solely by in-
ternal-combustion engines or by oil en-
pines in association with turbines sup-
plied with steam from oil-fired boilers.

The designs are under consideration,
and it is probable that of the 20 vessels
of this class provided for under the navy
estimates, two will have internal-com-
bustion engines. One has been ordered

TABI,E FOR DETEItMlNlNi; TIIP: HEAT EQEIVALE.NT OF THE roMIENSATE FRO.M
A OA.-i CAI.OIiniETEl! — HUITISH THEHMAE IXIT.<

Cniir Centimeters of

('OVOEN-S

\TE

Tt-mp..

Fahr.*

1

2

.■(

4

•'

6

7

8

9

10

.3.1

2 .5^

.5 04

7 .56

10 OS

12 60

15 r2

17.64

20.16

22 . 68

25 20

40

2 .51

.5 02

7 .5.)

10 04

12 .5.5

15.06

17 .57

20.08

22 .59

25 10

4.5

2 .50

.5 00

7 . .V)

10 00

12 .50

15 00

17 .50

20 00

22 .50

25 00

.50

2 49

1 9S

7 47.

9.96

12 4.5

14 94

17.43

19 92

22 4 1

24 90

5.5

2 4S

4 >M

7 44

9 92

12 40

14 S8

17. .36

19 84

22 32

24 SO

60

2 47

4 94

7 41

9 8S

12 3.5

14 82

17.29

19.76

22 23

24 70

65

2 46

I 92

7 .ts

B S4

12.39

14 76

17 22

19 68

22.14

24 60

70

2 4.5

4 90

7 .'t.5

9. SO

12.2.5

14 70

17.15

19 60

22.05

24 .50

75

2 44

4 .HK

7 .t2

9 76

12 20

14 64

17.08

19 .52

21 96

24 40

80

2 4.)

1 H«

7 29

9 72

12.1.5

14 .58

17.01

19 41

21 .87

24 30

85

2 12

1 S4

7 20

9 OS

12 10

14 .52

16 94

19 :J0

21 78

24 20

90

2 41

4 S-2

7 2.)

9 04

12 05

14 46

16 S7

19 2S

21 69

24 10

a5

2 in

1 SO

7 20

9 60

12 00

14.40

16. SO

19 20

21 60

24 (M)

100

2 3H

4 7K

■'"''■

9 .58

11 . 9.5

11 34

16.73

19 12

21 51

23 90

*Ti.'inp<Talurc of the pxhatist i;a.sc!! from the calorimeter.

in use; it is based upon the assumption
that when the gas is burned, the water
vapor it contains is condensed and low-
ered in temperature from 212 degrees
to the temperature of the issuing pro-
ducts of combustion.*

♦The formiiln for Ihe ticBt Elvpn up In
U.t.u. l8

r f97n 4 '^212 — 0

" " 154

r = riililr rrnllmelnrfi of rondrnMtP.
f — Tempprntiire of (tin riilorlmpt<"r exhnii»t
Ka«en. F.ihrpnhnll de(frp«*«.

in which it is intended to have a com-
bination system of engines. This is the
more convenient arrangement as the
same oil is used as fuel in the boilers and
in the internal-combustion engines, and
makes possible the attainment of the
normal cruising speed with these engines
alone working.

With this arrangement ihc advantage
of high economy will be attained at low
speed and the radius of action of the
destroyer at cruising speed will be ncarlv

558

POWER

October 10, 1911

doubled, exceeding 4000 miles. Oil fuel
for the boilers and the turbines for driv-
ing the wing shafts will still provide for
full speed when necessary, which can
be had within a very short time from
the steaming up of the boilers.

Although this is a limited application
of the internal-combustion engine for
warship propulsion, there is every prob-
ability that complete data will be ob-
tained to establish the suitability of this
prime mover for larger vessels and for
greater powers.

Diesel Enj^ines for Rome

The city of Rome, Italy, has contracted
with Franco Tosi, of Legnano, for three
6-cylinder Diesel engines of 2000 brake
horsepower each and two 3-cylinder en-
gines of 1000 horsepower each for cen-
tral-station service. These engines are
of the vertical form and will operate on
the two-stroke cycle at 136 revolutions
per minute. They will be coupled to al-
ternators which will deliver three-phase
currents at 8200 volts. The guaranteed
consumption of fuel oil of 18,000 B.t.u.
heat value is as follows:

age (
Fuel, pounds
■ brake hp.-

per t)i
fiour

1 139 0 ae.i 0 884 0.831 0 8,57

LETTERS

The Gas Turbine Problem

Mr. Blaisdell's suggestion of a two-
Huid turbine, presented in the September
5 issue, is extremely interesting and in-
genious but there are several drawbacks
which he apparently overlooked. One
serious mistake that he makes is the
assumption that the gas and air will
remain at the compression pressure when
delivered into a combustion chamber

Of course, I understand that the cham-
ber is filled with steam at 200 pounds
pressure before the explosive mixture
enters and that this steam is expected
to "back up" the inflow of gas and air
and keep the pressure up, but that ex-
pectation may easily fail to be realized.

A third oversight by Mr. Blaisdell
seems to be indicated by his assumption
that enough steam can be generated at
200 pounds pressure by the waste heat
in the exhaust gases. Assuming an ex-
plosion temperature of even 2500 degrees
absolute and adiabatic expansion in the
turbine, the gases could not leave the tur-
bine at more than 1160 degrees ab-
solute or 700 degrees above Fahrenheit
zero. The temperature of saturated
steam of 200 pounds gage pressure is
388 degrees and to make a pound of that
steam from water of, say 176 degrees
temperature {raised to that by jacket
heat from the compressor! requires 1050
B.t.u. The gases cannot possibly drop
more than

700 - 388 =312 degrees
in making the steam, so that in order to
make one pound of steam 13' i pounds
of exhaust gases would be necessary,
assuming 100 per cent, efficiency for the
boiler; at 84 per cent, efficiency the quan-
tity would be 16 pounds. In other words,
each pound of exhaust gases, and there-
fore of initial mixture, could make only
one-sixteenth of a pound of steam of 200
pounds pressure under the most favor-
able possible conditions. This would
not go far toward cooling the machine.
George W. Malcol.m.

New York.

I was very much interested in the arti-
cle entitled "A Suggested Solution of the
Gas Turbine Problem," by Benjamin H.
Blaisdell, which appeared in the Septem-

saturated steam. Still adhering to Mr.
Blaisdell's plan of cooling by means of
steam, I would suggest a mechanical
change in the apparatus to permit the
use of a steam turbine with the inter-
mittent gas explosion superimposed. That
is, have the steam continuously enter at
an individual nozzle, retaining the feature
of saturation regulation, and have the
combustion chamber jacketed with the
feed water and connected to a nozzle
of its own, separate from the steam
nozzle of the turbine. This arrangement
would obviate any objections due to the
flash-boiler effect, and it would increase
the possible number of cycles per unit
of time, because of the continuous steam
How and the resultant continuous cooling.
Walter Knapp.
Plainfield, N. J.

Performance of an Oil En-
gine Pumping Plant

A new pumping unit recently installed
at the Artichoke pumping station of the
Newburyport waterworks consists of one
50-horsepower De la Vergne oil engine,
type "H. A.." direct connected to a 12x12-
inch triplex single-acting plunger pump.
On a 9-hour test this outfit showed the
following results:

Kevolutions made by the pump

.shaft during test

Theoretical gallons of water

pumped (17.62.5x22,14y ).

.\llo\vaiice for slippage in pump . .

Ivstnnated gailons jiumped

Kstunalfd weight of water

I)uini»ed. pourid>

Tiital head against pump. feet. . .
Kstiniated foot-pounds of work

22,147
390.341
382,534
3,187,-

130

414.412,000

36i

11.353.7,50

The builders guaranteed a duty of 10,-
400,000 foot-pounds per gallon of fuel,
which was exceeded by a considerable
amount, as shown by the above figures.

otai fuel consumed (34 degree
liKtillatei. gallons

oot-pounds of pumping dutv per
gallon of fuel

-^■-

iMk. Blaisdell's Proposed Co.mbustion Chamber for a Gas Turbine

which opens into the turbine without
restriction. Another is the assumption
that the combustion chamber will fill
up with mixture at the compression pres-
sure before any of the mixture ignites.

ber 5 issue of Power. It seems to me When it is considered that the load fac-

rather doubtful, however, that the com- tor was around 50 per cent., the results

bustion chamber would be mechanically obtained are highly satisfactory.
able to withstand the flash-boiler effect L. C. Tucker.

due to intermittently introducing super- Newburyport, Mass.

October 10, 1911

POWER

Keg Tank. Float

Metal floats often cause trouble when
used to indicate the water level in a tank,
due to the cord sticking or to a leaky
float. I have successfully used a small
beer keg.

A flat bung is used to plug the bung-
hole. A hole is bored through the bung
and the stave exactly opposite to the
bung, and a piece of -^s-inch brass tub-
ing passed through them. The bottom
hole must be a little smaller than the tube,
so that the latter can be screwed in from
the top hole. The threaded ends of the
tube should extend '. inch on either side
of the keg. A socket hook is screwed on
to the upper end of the tube, and a
washer slipped over the tube on the other
side of the keg, followed by a nut, which
serves to tighten the rod to the keg. Such
a float is good for years.

William L. Keil.

Philadelphia, Penn.

Double .Eccentric Corlis.s
Valve Setting -*^

The object in having two eccentrics is
to give the engine a longer range of cutoff
which, in a single-eccentric engine, is
limited by the exhaust valves as the ec-
centric must be set ahead of the crank
about 115 or 120 degrees in order to give
the proper compression and release. My
method for setting the valves on a
double-eccentric Corliss engine is as fol-
lows :

Place the wristplates in the center of
travel. A mark will be found on the
wristplate hub and another on the stud.
If not, one can find the center of travel
by dropping a plumb line so as to coin-
cide with the center of the hook pin and
the center of the stud. Be sure that the
rocker arms are also plumb when the
wristplates are hooked up and are at the
center of their travel.

Now, adjust the valve rods until the
proper amount of lead is had (which is
1/64 inch for an 8x24-inch engine and
3/64 inch for a 30\72-inch( and adjust
the exhaust valves to the proper amount
of lap (3/64 inch for the 8x24-inch and
3/16 inch for .30x72-inch». Then,
with the crank on the head-end center
movt the steam eccentric ahead until
the hook rod just hooks up to the wrist-
plate, with the wristplate at the center
of lf« travel. This will place the eccentric
90 degrees ahead of the crank minus the
angularly of the Connectlne rod. With
the steam wristplate honked up. turn the
engine over to the crank center and see

if the same amount of steam lead is
had; if not, make up one-half of it by
moving the steam eccentric and the other
half by changing the length of the con-
necting rod.

Next, move the engine over until the
crosshead has reached a point about I'j
to 3'-4 inches from the end of the stroke
(according to the size of the engine! and,
with the exhaust wristplate hooked up,
move the exhaust eccentric ahead until
the exhaust valve on that end is just
closing. This will give about the right
amount of compression. Next, move the

centric, it will be necessary to change the
keyways in the steam-valve stems so that
the steam arms will be on a level when
the lead is had; if not, they will raise
too high. This can be done with an offset
key, but 1 prefer to turn the valve stems
over and cut new keyways and fill up the
old ones. The reason for changing the
position of the keyways is that the lead
is obtained with the wristplate in a dif-
ferent (earlier) position than that on a
single-eccentric engine.

Fred R. Hawk.
Kansas City, Mo.

Poorly Designed Bearing

\C'hen an engine is designed with the
bearings made as shown in the accom-
panying illustration, there will be a strain
and a heating of the shaft, because the
distance from the center of the bear-
ings is too great from the center line of
the crank rod.

The line A B, in the case of one en-
gine, has a vibration of at least 3'16
inch, and one of the two heavy wheels,
running at 240 revolutions, went to pieces
due to the strain placed on the spokes.

Faulty Design of Bearing

engine over to within the same distance
of the other end of its travel and observe
if the other exhaust valve is just closing;
if not, make up one-half of it with the
exhaust connecting rod and the other
half with the eccentric as was done with
the steam valves. After putting the valve
covers back in place the finer adjustmertts
with the indicator can be made.

If another eccentric has been added
to an engine which was built for one ec*

How long will the new wheel last under
this condition ?

The supporting surface at C D is too
small and too far from the force applied to
the crank's face, and ihc accident shows
that this form of bearing is not the best
suited for heavy loads: a bearing having
a support close to the face of the
crank is more desirable. Making the
crank shaft larger does not remove the
entire cause of vibration and the new
wheel will eventually give way from the
side springing motion as the slightest
play on the surface at /I R will cause
trouble.

C. R. McCahev.

Baltimore, Md.

560

POWER

October 10, 1911

Fixed Eccentric

The- engine in question had an 8x16-
inch cylinder and evidently the maker
did not conteinplate any change in the
valve setting as the eccentric was cast
solid with the hub of the crank.

Shortly before I made its acquaint-
ance a new valve had been made for it
and it required constant attention to keep
up steam. On e.xamination it was found
that on one end of the cylinder the steam
followed the piston 15 inches and on the
other stroke 15' S inches. As the eccentric
could not be changed, measurements were
taken and a pattern made for casting
a new one. The old eccentric and crank
were removed and the eccentric turned
down to form a hub on which to mount
the new one.

After fitting the new eccentric and
strap in place and setting the valve
to cut off steam at 7 inches of
the stroke, the eccentric and hub
were marked for keyways. When the en-
gine was started up it ran smoothly and
it only required about one-half as much
fuel as before to keep up steam. In
this case it was the late release, no com-
pression and late port opening that caused
the trouble; it was remedied by advanc-
ing the eccentric.

J. C. Hawkins.

Hyattsville, Md.

Condemns License Laws

For five years I have held a license as
a stationary engineer and have had
enough experience to reach a fair under-
standing of the advantages and disad-
vantages of such a law. It has a few
good points. In studying for examina-
tion, the applicant naturally becomes
more interested in his line of work and
becomes acquainted with new ideas, laws
and rules which, otherwise, he would not
have known. But many of these men
lose all interest after getting a license.

As for wages, they are no higher in
licensed States than in those not licensed,
and the hours are no better.

I know of a case where a licensed man
gave 10 days' notice of resignation to a
company and, upon his leaving, a non-
license man of extreme ignorance was
given the plant, although he had been
refused a license the third time. The
district examiner was verbally informed
and was asked to take up the matter and
see that a licensed man operated the
plant, but he was allowed to run over a
month and the company took its time in
putting in a permanent man.

Violations of this law are very com-
mon, but there are but few prosecutions
for its violation. If there were more
prosecutions the law would meet with
more favor.

Engineers must take the examination
and pay their S2 whether they pass or
not, and in some States and cities they
pay $2 for the renewal of the license.

They are held liable for violations and
run the risk of losing their jobs; what
benefit do they receive from the law?

One contributor recently asked how
some of the kickers against license laws
would like to see laborers taken out of
a trench and put in charge of steam boil-
ers as has been done in no-license States.

I know of men holding licenses who
worked in a trench and ought to be
there now. A capable man, having charge
of nearly 1000 men in a license State, in
discussing licensed engineers, said that
he could take any one of these men dnd
get them a license inside of 30 days.
Judging from some of the engineers he
had they must have been 30-day men.
Ray Gilbert.

Virginville, W. Va.

Painting Engine-room Floors

Various methods are in vogue for the
treatment of concrete floors of engine
rooms, and 1 have tried most of them
with various degrees of success.

A concrete floor is in itself very porous
and readily absorbs grease, dirt, lubri-

scrubbed by the use of a live-steam hose,
caustic-soda or an acid solution. The
floor should have time to dry before ap-
plying the paint with a brush; then be
sure that it is well worked into the con-
crete.

The first coat should be allowe'd to dry
for 48 hours and be hard before apply-
ing the second coat. The paint renders
the concrete floor impervious to water or
oil, as it closes the pores; it also pre-
vents concrete dust which is a nuisance
in an engine room.

I have also put into each engine room
a strip of woven-wire matting as it in-
creases the life of the painted floor.

In cleaning the painted floor, waste
and soft rags can be used to wipe up;
never use caustic soda or hot water.

A. Ralch.

Swissvale, Penn.

Compression Unnecessar}

The diagrams shown herewith were
taken from a cross-compound Corliss en-
gine with cylinder diameters of 22 and

Fig. 1. High-pressure Diagra.m

eating oils, etc., so that it is an endless
task to keep an engine room neat and
clean.

I finally painted the concrete floor with
a dark slate-colored paint, and after six
months' wear the experiment was so sat-
isfactory and the improved appearance
of the engine room so remarkable, that
I have painted six other engine-room
floors in the same manner. There are

40 inches, stroke 36 inches. The am-
monia cylinders were driven tandem with
each steam cylinder. The engineer of
the plant would like to have the read-
ers of Power suggest any changes that
might be made in the valve setting to
give better results.

S. KlRLlN.

Mobile, Ala.

[When ammonia compressors are ar-

Fic. 2. Low-pressure Diagra.m

several manufacturers who furnish con-
crete-floor paint and will send color cards
and samples to those interested.

Before applying .the paint the concrete
floor should be thoroughly cleaned and.

ranged in tandem with the steam cylin-
der of an engine no compression is re-
quired in the steam cylinder, as the com-
pressor will furnish all that is necessary.
— Editor.1

October 10, 1911

P O \V E R

5(1 1

Piston Rod Packing

I recently had occasion to remove the
plungers from a duplex vertical com-
pound boiler-feed pump and true up the
rods on a lathe because ridges had been
worn in them by sand. etc. A cut of
about 0.026 inch was taken off, and when
the pump was assembled and tried out it
leaked badly at the stuffing boxes. This
was due partly to the water coming from
a heater at a temperature of about 180
degrees which affected the packing, and
partly because of the cut taken from the

Brass Ring ^

'm-j^

Hovi- THE Rod Was Packed

plunger rod which left the stuffing box a
little loose.

The stuffing boxes were adapted to
metallic packing, which was put in when
the pump was assembled. Nearly every
kind of packing was tried, but it was in-
effective. A cylindrical piece of brass
8 inches long was used which was large
enough in diameter to tit the stuffing
boxes of the pump when the brass was
turned down.

Four rings were made, each about 5^
inch thick outside, 'i inch inside, m inch
wide and about 9 inches in diameter.
Each ring was beveled from the outside
toward the center. Four bolt holes were
then scribed on the face of each ring
and drilled and tapped for ;4-inch bolts,
thus making it easy to lift them from
the stuffing boxes by screwing two 'j-
inch bolts in each ring. These rings were
sawed in half because the pump was so
designed that it would have been neces-
sary to take it apart in order to put them
in whole.

Some M-inch flav packing coated with
graphite was at hand, and after placing
one of the brass rings in the bottom of
the stuffing box with the beveled side
toward the gland, we put in these rings
of flax packing, leaving room for the
other brass ring; the rings were placed
in the opposite position to the first and
having the flat side next to the gland, as
shown in the illustration. The same treat-
ment was given to the other three stuff-
ing boxes. The gland was tightened, thus
forcing the packing toward the plungers.

With an occasional forcing in the gland,
the stuffing boxes have held tight for 10
months.

If trouble is had with sand in the
pumps, I advise the use of a ring of
woven copper packing in the bottom of
the stuffing box before placine the first
brass ring.

Waltkr a. Cox.

West Orange, N. J.

Jacobs-Sluipert Locomotive
Firebox

The Jacobs-Shupert locomotive-boiler
firebox possesses the novel and com-
mendable feature of being constructed
without staybolts. At least, my impres-
sion is that it is so built.

Why could not this type be adapted to
stationary boilers to good advantage?
Lloyd V. Beets.

Nashville. Tenn.

Homemade Indicator Reduc-
ing Motion

The accompanying sketch illustrates a
homemade indicator reducing motion. It
is a neat arrangement and accurately
transmits the crosshead motion, as it has
not the error due to the use of an arc.

Pl _ E -u

-3

Indicator REni'ciNc. Motion

This device is attached by two studs
A to the guide barrel of the engine, and
is placed as near as possible to the cen-
ter of motion of the crosshead. The sup-
port B is made of Ix'i-inch flat steel,
forged to the required shape and then
polished. The pieces C and D constitute
a slide and its guide. They are made of
brass and polished. The pin £ is screwed
into the slide D and has a groove to
which is attached the cord leading lo the
indicator, and the frame H is slotted at
F and (1 so that C can be raised or low-
ered, thus shortening or lengthening the
stroke of E, according to the stroke of the
engine.

The arm // is made of flat steel and is
polished. The slots at .S and K must be
carefully made so that there will be no
looseness in the pins F. and /.

The two nuts at /. and M clamp the lop
pin to the frame, and the outside nut
prevents the arm H from working off, but
it must be loose enough to allow the ann
H to swing freely. Pin J is attached
rigidly to the crosshead, usually by
screwing it into a hole made for that

purpose. As the crosshead moves for-
ward and backward the arm H transmits
the motion to the pin E. and to the indi-
cator by the cord.

The device may seem more complicated
than is necessary with no decided ad-
vantages, but with all the parts polished
it makes a very attractive addition to the
engine. When not using the indicator
the arm H can be easily disconnected.
There is no figuring for any special size
as the device will fit any engine by ad-
justing C.

Earl Lyon.

Oakland. Cal.

Keyed Piston Gave Trouble

While working as an operating engi-
neer some years ago I had an experience
with a tandem-compound engine which
I will long remember.

The pistons were made with a taper fit
on the rods and were held in place by
keys.

A pound, which only came once in a
while, would sometimes disappear for a
week at a time, but when it did come
the whole engine would shake.

Bent Key

After trying all kinds of adjustments
on th? pillow block and connections I
still got the same pound at times, al-
though the indicator cards showed good
valve adjustment.

Then 1 decided that the pound was in
the low-pressure cylinder. I backed the
piston rod out of the crosshead, and
started to drive the key out of the low-
pressure piston, when I found that the
piston was upside down on the rod.

The only thing to do was to swedgc
the key out a little and drive it back
in again. I then tried the key on the high-
pressure piston and found it offset as
shown in the accompanying illustration.

The high-pressure piston had been
pounding by being driven up on to the
taper of the key. I chipped out the key-
way so as to allow the key to draw up
the piston on the rod and made a new
key. The engine was then put together
and gave no more trouble.

S. H. WiNTON.

Woonsocket. R. I.

A locomotive of 100(1 horsepower driven
by a Diesel engine has just been set lo
work on the Prussian State Railways.
The drive is direct to the axles, and the
outward appearance is similar lo that of
an electric locomotive. Nearly S60.000
have been spent in experimenting with
this engine.

562

POWER

October 10, 1911

1

C: ^ ' '

ri 'i S 4. >

1 I^^^^^J.O^^

Central Station vt-rsus Isolated
Plant

Not realizing at the time I wrote the
article published in the July 11 issue
that so much interest would be shown
in my case, I did not make myself as
clear as I might have, so I will use John
Bailey's questions in Power, for August
29 to clear up my former statements.

I am not in possession of the central-
station prices; besides, the power will
be used in all three buildings, X, Y and
Z, shown in Fig. 1 herewith, whereas but
two were supplied by the steam plant.

There are no other plants in the
vicinity. The shop was located on the
present site in 1790 to get the use of the
water right.

The central station already has poles
by and beyond the shop for town street
lights and only had to extend its high-
tension lines three miles to connect up.

Building X is the only one heated by
steam and 2 pounds pressure is sufficient.

The plant is already motor driven. All
that was necessary was to step the high-
tension current down to 550 volts and
install a double-throw switch in place of
a single-throw, current in both cases be-
ing three-phase, so that feature was
easily taken care of.

The high cost of coal is due largely to
transportation and to transmission losses

it and the waterwheel might operate the
same jack shaft. As to the 25-pound
drop, the pipe is 5 inches to the last ell,
which is a reducing ell 5x4 inches. Also,

Fic. 2. Main Bearing Design

there is present a large amount of con-
densation with no separator to take care
of it.

The feed-water heater is a Patterson-
Berryman, but as the feed pipes prac-
tically follow the line of the main steam

"'/.■,y,;':Y//VSZZ

Now I am aware that on the face of
the inatter there is chance for criticism,
so I wish to state some of the various
improvements I recommended. One was
to cover the ells on the main line, and
to cover the feed-water line. Then I
tried to induce the manager to let me use
buckwheat and install proper furnaces
to burn it economically. Then there was
talk of putting the engine close to the
boiler, discontinuing the waterwheel
(there is not water enough for it 10
months in the year) and running con-
densing. Another suggestion was to com-
pound the engine as there are 20 pounds
at the point of release.

The key to the situation is just this:
the former management, which lasted for
17 years and ended a year ago, was of
the old school and could not appreciate
the importance of present-day practice;
also, the business was run nearly into the
ground. When the new man took hold
there was so much to be done in the way
of repairs, remodeling and reviving
the business and so much expense
to put the power plant on an economical
basis that everything could not be
done. The production end had to be
considered first for without that no power
would be needed, so my department had
to be the one dropped. Another item of
expense would have been the rebabbitting
of the main bearings of which Fig. 2 shows

FuU Load

Fig. 1. Arrangement of Buildings

No Load
Fig. 3. Indicator Di.\gra.ms

of the steam. The straight pipe is covered;
the elbows are not. The necessity for
148 feet of pipe and 7 ells lies in the
fact that the engine was placed so that

line and are bare the gain is not much.
The gages are correct, according to the
Hartford Steam Boiler Inspection and
Insurance Company standard.

the design. They are just simple bearings
with no takeup other than liners, and so
badly worn on the side toward the cylinder
that the piston and valve ends were taken

October 10, ISll

POWER

563

up to the limit in order to keep the clear-
ance and valve setting right. As will
be seen from the indicator diagrams in
Fig. 3, there is still an inequality.

All in all. the central station has had a
very good chance, and for myself 1 can-
not blame anyone. 1 must say that had
the general manager and myself ex-
changed places, I should have done as he
did. I think.

Em.met Baldwin.

Sturbridge. Mass.

To Prevent Standpipe
Freezing

In response to Mr. Nicholson's in-
quiry in the September 12 issue I sug-
gest the following arrangement to prevent
a standpipe from freezing:

Use an ejector, size about 1 inch; the
suction side of the ejector to be con-
nected with the standpipe. the discharge
side of the ejector also to be connected
to the standpipe. Both connections should
be made c'ose to the bottom, the holes
for the two connections being about 3
feet apart. Then, when the steam con-
nection is made to the boiler and the
steam is turned on. the warm water will
circulate through the ejector, thus warm-
ing the water in the standpipe and caus-
ing a circulation.

The office of the ejector is to quiet the
noise of the steam when coming in con-
tact with the cold water, which noise
would be objectionable if the steam were
turned directly into the standpipe. It is
understood that the discharge must enter
at the lowest point of the standpipe as
all water below this point would be
likely to freeze, and the warm water
would never go downward except by force.
If the bottom of the standpipe is not
accessible, theii the discharge from the
ejector must be projected inside and
downward to the bottom and there turned
horizontally.

D. M. Sullivan.

Camden, N. J.

Potblyn, Pump Doctor

Referring to Mr. Watson's excellent
story in the issue of September 19 unlSer
the above caption. I have had many
•-oubles such as he describes. In one
-tance we were using live high-pres-
;rc steam for glue kettles and drying
apparatus. The returns from these passed
through traps to a receiver tank and
when the pump was not steam bound the
gravity low-pressure heating syslen
would be air bound. There was a vent
pipe with a stop valve on it connected
to the top of the tank. With this valve
closed and the gravity returns shut off,
unless some of the traps were discharc-
ing, there would be a vacuum in the lank.
The suction pipe of the pump was con-
nected at the bottom of the tank and rose

about 2 feet to the pump. With the tank
half full of water at 212 degrees, giving off
vapor, the pump became steam bound.
Cooling it with water worked well if the
water in the tank was cooled and a proper
amount of air admitted or a small steam
pressure put upon it to break the vacuum
in the tank. A small valve closed by a
small spring and opening inward admitted
air and prevented a vacuum forming.

The vent valve opened whenever the
low-pressure return pipe became air
bound, and cold water was admitted to
the suction pipe when the pump became
steam bound. Either of these troubles
would cause the pump to run fast or run
with a jerking stroke and pound.

I tried to get a trap to put on the heat-
ing system. This would permit taking
the pressure off the tank by leaving the
vent open. But the management could
not see the benefit to be derived.

In a plant where there was an indirect
heating system and where live and ex-
haust steam were used for various pur-
poses traps were employed, which dis-
charged into a return tank. This tank
had all of the return pipes connected into
or near the top. and a gooseneck water
seal at one end. With the tank full of
water, when the engine stopped the two
heater coils would immediately be filled
with water. These coils, consisting of
four radiators each, discharged through
one large trap. This was the first case
1 had experienced of a vacuum in the
coils drawing the water back through
the trap. With the tank only half full,
the water being below the discharge pipe
from the trap, only air would pass
through the trap to the coils.

There are some traps, such as those
with valves of the piston type, which
would prevent this trouble.

The feed pump would occasionally get
steam bound due to the returns being
too hot.

The closed heater had a 1-inch drip
pipe without a stop valve in it. draining
the heater of condensation which carried
with it much cylinder oil that would other-
wise go up into the heating system.

When I took charge of this plant I re-
marked the waste of steam through this
pipe as if it had no stop valve on it. What
I could not understand was why this
pipe did not supply the coils with air
enough lO destroy the vacuum forming in
it. I was told that the pipe was to be
left open to insure the drainage of the
oil from the heater. On my search to
find out why the air did not go back
through the pipe, down in a comer under
a pile of old grate bars and other junk
I found a il-inch check valve, the pipe
having been reduced to this size, and
the drip from above the throttle connected
to the I'l-inch nutlet, beyond. This told
the story. The check valve closed against
the inrush of air and consequently the
air had to pass through the return lank
to the manifold coils.

In another instance, I was called by
my fireman to attend to a pump which
seemed to run well hut would not feed
the boilers. The pump rested on a founda-
tion about 18 inches above the floor while
the tank was below the floor. Most of
the return pipes entered at the bottom of
the tank. The 4-inch suction pipe passed
down to within 6 inches of the bottom.
There was no pounding to mention, but
the pump did not discharge any water.

After studying a while I concluded that
the pump was air bound, although the
tank was full of water. So, closing the
discharge valve and opening the drip
from the discharge chamber, I ran the
pump slowly and the air was soon ex-
pelled. The fireman admitted later that
the tank had been pumped dry. The air
in the suction pipe had filled the pump
cylinders and the pistons would simply
compress it against the discharge valves
without opening them.

What 1 would like to know is this, why
will an air pump work with a vacuum in
the suction pipe while a boiler-feed pump
will not take water from a heater in
which there is a vacuum?

R. A. CULTRA.

Cambridge. Mass.

Massachusetts License Laws
and Examiners

The letter of J. A. Levy in the August
1 number has opened a discussion of
much interest to engineers in this State.
Most of the letters in answer to his have
made no defense of the present license
law or method of examination other than
to belittle him, thereby drawing attention
from the real issue, which is the method
of examination.

That I may escape being called "sore-
head" and other undesirable names. I
wish to say that I have held a first-class
license for ten years. Perhaps 1 should
join with certain other engineers who
have "got by" and denounce everyone
who makes a protest against present con-
ditions; anyone can easily see that if
the number of first-class licenses is
limited those who have "got by" will
benefit.

T believe the Massachusetts license law,
especially after the recent amendments
go into effect, is the best I have heard
of; but that is no reason why it should
not be criticized. Engineers' license laws
are supposed to be for the protection of
the public — not to raise the wages of the
engineers or to provide jobs for inspectors;
therefore the examination should be t"
determine if the applicant is capable of
operating a steam plant safely, and when
an inspector goes further he oversteps
his authority. The law expressly says:
"The applicant shall be given a practical
examination," etc.

It seems to mc that the trouble with
the examination is in the interpretation of

564

POWER

October 10, 1911

the word practical. The dictionary de-
fines the word thus: "pertaining to prac-
tice, action or use; not merely theoretical;
that reduces knowledge or theories to
actual use; derived from practice or ex-
perience; skilled in actual work," How
can certain examiners square their ques-
tions with that definition?

If every first- or second-class engineer
is required to design a boiler, why do we
have need of a board of boiler rules in
this State to lay down rules as to how
every boiler shall be built (the boiler-
!nakers having to conform to these rules) ;
it would seem that the engineers' ex-
amination should cover the care and op-
eration of boilers and not their design.

I am a member of an organization of
engineers that has a membership of over
200, and there have been questions dis-
cussed at the meetings that have been
asked applicants for second- and third-
class licenses that could not be answered
by first-class engineers. These engineers
are advised by one writer to "take down
their dust-covered books and magazines
and get busy and that 'something wrong'
spoken of by Mr. Levy would disappear."

The most of us are too busy studying
how to keep down the cost of power as
the price of coal mounts higher to waste
tiine with a question asked by some ex-
aminer which has no bearing on the safe
operation of a steam plant. I do not wish
to be understood as criticizing all in-
spectors or examiners.

There is one here in the west end of
the State of whom I have never heard a
complaint; he has held his job for many
years; everyone speaks well of him; but
every applicant he examines is satisfied
when he comes out of his office that the
examiner has found out all he knows
about engineering and that he has not
been attending a pink tea. This examiner
uses tact, judgment and patience, gives
the applicant a practical examination and
does not bulldoze him.

The inspectors say they have orders to
stiffen up on the examination. Where
did these orders originate? We are sure
the legislature has not ordered a more
thorough examination, so the order must
come from somewhere within the boiler-
inspection department. Why should the
department wish to make the examination
harder? Have accidents been caused which
could have been prevented by a stifFer
examination of someone? I think not.
Many stories are in circulation as to why
the e-xaminations are harder than former-
ly; some think certain engineers holding
first-class licenses have brought pressure
to bear on the boiler-inspection depart-
ment in some way, that they may limit
the number of first-class engineers. That
hardly seems possible, yet we remember
a few years ago there was quite a stir
about the special-license clause in the
law. An amendment was presented to
the legislature and adopted, limiting the
issue of special licenses to have charge

of plants to those not exceeding 150
horsepower (the second-class limit).

It does seem peculiar that the special
license should apply only to second-class
plants and below. If I held a second- or
third-class license, I should feel that
someone was "putting it over," especial-
ly, since the legislature has been.in ses-
sion four times without any attempt at
relief for the second- arid third-class
men. I have heard chief engineers say
they preferred men with special licenses.
One said lately that he would fill the
next vacancy with a special-license rrian,
and gave as his reasons that a special-
license man would stay with him, but a
man with a regular license was always
looking to better himself and might leave
him. It seems strange that steam plants
up to 150 horsepower are safe in charge
of special-license men while those above
that size are not. There are those who
say that the trade schools and those hav-
ing books for sale have something to
say about examinations. People who thus
criticize the method of examination may
he "soreheads," but it is a fact that their
number is growing rapidly. If the ex-
amination is made harder, to protect the
public from men' operating dangerous
machinery who are not competent, why
do the examiners grant men special
licenses ( with practically no examina-
tion), to have charge of a steam plant
who they claim are not competent to
carry a classified license covering the
plant?

If special licenses must be issued, they
should be limited — that is, the holder of
a special should be required (say in six
months) to pass the examination for a
regular classified license covering the
plant. At the present time, if an accident
happens, the boiler-inspection department
steps in, and if the engineer is found
negligent his license is revoked. This is
as it should he, but it is far more neces-
sary to prevent accidents than to punish
someone for negligence afterward. Every
steam plant should be visited at least
once each year by an inspector whose
duty it is to see that all boilers, engines,
piping, etc., are in a safe operating con-
dition; the owner would then learn that
because a man holds a first-class license
it is no proof that his plant is in a safe
condition.

Visit some of the 'arge electric-light
or street-car power stations about 6 p.m.,
when the peak load is on, and you will
find many engines running with the pin
in the governor column which means
a runaway engine if the governor belt
breaks or slips off. Look at the boilers
and piping, many of them are running
on the "ragged edge" till a more favor-
able time for repairs. Never mind the
danger to life or serious injury, the wheels
must be kept turning. I mention these
types of plant particularly as they are al-
ways in charge of men carr>'ing first-class
licenses.

I wish to call attention to the need of
at least annual inspections of all steam
plants by competent men. Mr. Levy
says he "hopes to see this vitally im-
portant matter liberally discussed in the
columns of Power." I fear he will not
hear from many of the second- and third-
class engineers, the men who are most
interested in the subject; they are afraid
to criticize existing conditions because
they will be "spotted" by the examiners.

I have talked with a number in this
section and they agree with Mr. Levy,
but they fear to come out openly. I be-
lieve in license laws, in the Massa-
chusetts law if we can get no better; I
believe the second-' and third-class li-
cense holders, are not getting a square
deal, and that the examinations given by
certain examiners are not practical.

C. C. Harris.

Springfield, Mass.

.After reading the various criticisms in
the September 5 issue on Mr. Levy's
letter in a previous issue under the above
title, I am moved to take up the cudgel
in his behalf for I think he has been
brought to task a bit unjustly. I am
quite familiar with the particular case
of which he wrote. In fact, I had the
opportunity of giving the applicant in
the case a preliminary examination, at
his request. It seemed certain to me that
he would pass the examiners' ordeal with
flying colors.

I believe it is the duty of the examiners
to ascertain how much an applicant
knows about engineering rather than to
try to confuse and disconcert him. The
law has always explicitly stated that
an applicant should be given a practical
examination.

S. F. PUSTUN.

Springfield, Mass.

Status of the Engineer

I have read with much interest the
editorials and articles which from time
to time have been published in Po>xer
on this subject, and I have long ago come
to the conclusion that if an engineer per-
mits his employers, or supervisors to
treat him with just about as much, if
not less, respect than is given to the or-
dinary laborer, it is more or less his own
fault; in my opinion, an engineer who
does not uphold the dignity of his posi-
tion at all costs degrades the whole pro-
fession in a greater or lesser degree.

With this in view. I would like to re-
late an experience I had a couple of years
ago with an employer who thought his
engineer should be his loblolliboy and
to whom he gave less respect than to the
commonest laborer about the plant. It
was an ice-making and cold-storage plant
of about 120 tons capacity per day, run
on the ammonia-compression system; a
.^5-ton Linde machine had been installed
by the then chief engineer who had with

October 10. 1911

P O ^X' E R

565

his own men put in the concrete founda-
tions, assembled and erected the engine,
compressor, condenser, etc., and started
the machine without any outside help.
This was done in addition to his other
duties, for the other portion of the plant
was running continuously. The manager.
who was also a shareholder and director
of the company and posed as an amateur
engineer, although he had been a captain
on a Nova Scotian brig, thought he had
reason to be dissatisfied with the per-
formance of the new machine, as well as
the work of his engineer. Consequently.
he wrote back East asking the makers
to send him a first-class engineer, as he
could get nothing but "shovels" on the
Pacific coast.

As luck would have it, I was asked if
I would go out to the Pacific coast to take
charge of this plant. I demurred for a
considerable time, as I then had a good,
comfortable position as engineer in one
of the largest bank buildings in the
East; however, after a correspondence
extending over some four months. I came
out here to the coast, with the promise
of my transportation being paid and S150
per month salary.

Immediately upon my arrival I reported
to the manager, whose character became
apparent before I had had 15 minutes'
conversation with him, and I knew there
was trouble coming. As I had to get my
license, he took me over to a neighboring
town and introduced me to the boiler in-
spector, who gave me a special three
days' examination for a first-class certifi-
cate, which I secured.

Before I had had charge of the plant
a month the manager and I were at log-
gerheads, as he had the habit of wander-
ing about the engine room, and altering
the ammonia-expansion valves on the
headers to the coils in the brine tanks,
and to the different rooms for fish freezing,
meat storage, egg and butter rooms, etc.

At last I could stand it no longer, and
I ordered him out of the engine room,
quietly informing him that the plant was
run on my certificate, and that I was the
responsible engineer. After this, he got
very friendly with my assistant, who kept
the night watch from 7 p.m. to 7 a.m.
He pursued the same tactics after I had
gone for the night, with the result that
on one occasion when I came down in
the morninn. I found that not one pound
of ice had been made in the 12 hours, and
the temperature of the brine was stand-
ing at 2S degrees Fahrenheit.

I immediately charged my assistant
with collusion with the manager, with
whom, when he put in an appearance I
had a battle royal, for I had found all
the expansion valves had been altered
again. The manager demanded my resig-
nation, which I refused: he then said he
would be obliged to discharge me that
evening, to which I submitted, merely re-
tnarking that he might prepare himself
for the consequences.

The next day 1 put the matter into the
hands of an attorney, and commenced a
suit for a month's salary in lieu of notice
of dismissal, etc.

The manager denied owing me any-
thing and further wrote he had to dis-
charge me for incompetency. I immedi-
ately entered action for SIOOO damages.
The case was tried in the superior court
and took four days, as the manager
brought 19 witnesses, all, of course, in
his employ, while I was alone and 3000
miles away from friends. However. 1
won my case on every point, and got
my salary, damages, transportation, etc.,
the other side having to pay all court costs.

Now for the sequel. My former as-
sistant was appointed chief; and before
he had the position three weeks he burnt
both boilers and brought down the fur-
nace crowns through letting oil get into
the boilers. This happened in the very
hight of the summer season when the de-
mand for ice and cold storage is greatest.
The whole plant was shut down for six
weeks to make repairs to the boilers. To
keep their trade, ice had to be bought
at another factory 30 miles away and
shipped in for distribution; several thou-
sand dollars worth of beef, mutton and
produce were also spoiled through not
being able to keep the temperature of the
cold rooms down. Altogether, it cost the
company some SI2,000 because their
manager and director thought he knew it
all.

It does not always pay to interfere with
a properly qualified and competent engi-
neer when he is attending to his duties
in a proper manner.

John Creen.
Seattle, Wash.

Indicator Diagrams

Some time ago there was an article in
Povt ER dealing with indicator diagrams.
Among others was shown a valve-gear
diagram, or one made with the drum
motion taken from the eccentric rod.

I submit the accompanying diagrams
taken from a 16x36-inch Fitchburg en-
gine having a cam-motion valve gear and
running 100 revolutions per minute.

All of the diagrams were taken with
a 60 spring and with the same reduc-
ing motion, but as the travel was not
the same at the different points where
the string was attached the lengths of
the diagrams differed as might naturally
be expected.

Notice tliat the compression curve and
the point of admission show very plainly
on the diagrams in Figs. 2 and 3.

L. A. FiTTf.

West Fitchburg. .Mass.

Testimonial Letters

In a recent issue there were two testi-
monial letters regarding a well known
and reliable make of indicator. They
were written by a Mr. Cole who "upon
applying the instrument" found he "was
pulling almost one-fifth more load from
one end of the engine than from the
other, which naturally caused a pound."

DlAC.R.\.MS FRO.M UNBALANCED ENGINES

( Incidentally, it may be stated that about
a month after indicating the pound Mr.
Cole was advanced from engineer to man-
ager of the plant. I

It would be quite interesting to see the
"before" and "after" diagrams, accom-
panied by a description of what lost mo-
tion was taken up before the pound was
eliminated.

Several times I have secured diagrams
from engines which were unbalanced to
such an extent that the lights showed
plainly the uneven action, but there was
no pound when the bearings were all in
good condition.

The accompanying diagrams were taken
from a generator engine supposed to run
at 250 revolutions per minute, and, al-
though the indicator proves the engine to
have been in an almost single-acting con-
dition, yet there was no sign of a knock.

If Mr. Cole is still a reader of Power
I would be pleased to have him estimate

\l

Fig. 1. Diagrams Taken
IN Usual Manner

Fig. 2. Diacra.m.s Taken
WITH Drum Motion Re-
ceived FROM Cam Rori

Fig. 3. Drum Mo-
tion Taken from
Exhaust Eccen-
tric Rod

The diagrams in Fig. I were taken in
the usual way. Those in Fig. 2 were ob-
tained with the drum motion taken from
the rod which connects the lower ends
of the cam levers. The diagrams in Fig.
y were taken with the drum motion from
the exhaust eccentric rod.

the pound that ought to synchronize with
the accompanying diagrams.

By all means, keep the engine bal-
anced but do not overlook the rod brasses,
etc.

J. A. Carruthers.

Hosmcr. B. C.

566

POWER

October 10, 1911

Tf "S "^ T*?'^ -'€'.?

. O

\d:

-f-f

Relation of Belt Sf^eeti to Pulley

l^iai/ieter

Does the diameter of a pulley control
the speed at which the belt travels?

W. A. W.
. At a given belt speed the revolutions
of either driving or driven pulleys are
proportional to the pulley diarneter. The
diameter of either pulley multiplied by
3.1416 and by the revolutions per min-
ute of that pulley will give the belt speed.

Belt for Given Horsepower

A 4-inch single belt transmits 14 horse-
power, the driving and dri\'En pulleys be-
ing of equal diameter and revolving at
400 revolutions per minute, neglecting
slip. Find the size of these pulleys.
A. D. B.

Any one of a number of rules may be
used for this problem, depending upon
the working tension allowed per inch of
width. Selecting formula 4, page 877,
"Kent," in which the working tension
is taken as 45 pounds per inch of width,
for single belts,

„ . WTl

rtorscpowcr =

733

where

»= Width of belt in inches;
i'=Velocity of belt in feet per min-
ute, which is equivalent to

TT X d X r.fy.m.

12

in which d is the diameter of the pul-
ley, in inches, and r.p.m. represents the
revolutions per minute.

The formula may be expressed as,

„^, w X T X (I X r.p.m.

ttorscpouer = — — !- ;

7.« X 12

Substituting the known values,

4 X 3.1416 X d X 400

733 X 12 —^^

j_ 733 X 12 X 14 . ,

— . ^ .„„ -^ ? = -4-'S inches

4 X 400 X 3. 14 1 6 ^ '

A 24-inch pulley would suit the purpose.

S/ze of Corliss Engine Governor

How could one tell by simply looking
at it if the governor on a Corliss engine
was large enough for the work? This
question was asked me at a recent ex-
amination.

E. H. H.
The question is intended to test the
familiarity of the applicant with the func-
tions of the Corliss-engine governor. It
has practically no work to do. It simply

The horizontal distance from the load
to the mast is 19.15 feet. The moments
about the point of support G must bal-
ance.

3000 X 19.15 = G' X 24
--.. .3000 X 19.15

= 2400 pounds

horizontal pressure at G'.

adjusts the cutoff. .Any governor which
a builder of Corliss engines would put
on would be large enough.

Strrss in Crane Members
If a load of 3000 pounds is supported
by a crane of the dimensions given in
the figure, what is the stress in the strut
S, in the rod T and the horizontal pres-
sure against the top support of the mast'
P. J. F.
The compression in the strut is com-
puted by multiplying the load in pounds

Sketch of Crane

by the length of the strut in feet, divided
by the horizontal distance from the base
of the strut to the point of attachment
of the tie rod.

3000 X 7^ = 3428 pounds

compression in S.

The tension in the tie rod is found by
multiplying the weight in pounds by the
length of the tie rod in feet divided by
the horizontal distance between the point
of attachment of the tie rod to the mast
and the base of the strut.

3000 X ^^ = 2857 pox^nds

tension in 7.

Diameter of Stay bolts

The pitch of the staybolts in a boiler
is 6 inches each way and the pressure
carried is 100 pounds per square inch.
What diameter of staybolts will be re-
quired if the stress allowed in the bolts
is 6000 pounds per square inch?

F. L. H.

If the pitch of the bolts is 6 inches,
each bolt will support 36 square inches
and at 100 pounds pressure per square
inch the total pressure supported by each
bolt will be 3600 pounds. If a stress of
6000 pounds per square inch is allowed
upon each the area will be
6000

3600

1.666 square inches

at the bottom of the thread. The nearest
commercial size will be I-vg inches diam-
eter.

Advaiitat^es of Butt and Strap
Joint

What are some of the advantages of
a butt and strap joint over a lap seam?
C. A. S.

The lap seam will not permit truly
cylindrical construction and hence a bend-
ing action or flexure occurs along the
seam which frequently results in an ex-
plosion. The butt joint, double strapped,
allows truly cylindrical construction of
the shell and no flexure takes place with
pressure changes. The longitudinal seam
is the weakest part of a boiler. Double-
riveted lap seams usually are 70 per cent.
as strong as the solid plate, while butt
joints are from 85 to 94 per cent, as
strong as the whole plate.

The electrification commission of the
Chicago Association of Commerce, which
is just beginning a comprehensive in-
\estigation of the municipal problem indi-
cated by its title, has determined, as
one of its first deliberative acts, to adopt
the Ringelman chart system as a basis
of comparison to determine the density
of smoke. The next "act" will be the
choosing of competent inspectors.

October 10, 1911

POWER

567

Issued Weekly by the

Hill Publishing Company

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505 Pearl Street, New York.

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Entered as second class matter, De-
cember 20, 1910, at the post office at
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of March 3, 1879.

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( lucuLA rio\ ST A ti:mi:.\ r

Ot thi» issue 30,000 copies are printed.

Xone tent free regularly, no returns from
fleici companies, no back numbers. Figures
ere live, net circulation.

Contents pagb

\ Light, Heat. Power and Ice Plant 542

i'.'.iier Kfficlency of 83.69 Per Cent 544

:in;ine and Machinery Foundations 547

'":i\ Handling at Muncle Electric JAf:\it

Plant 549

• Steam Turbine In Germany 550

^^tc of Power In T'nallned Shafting... 553

Iny Faces and Belt Speeds for Medium
Spend Motors 554

rling Kotaiy Converters from the Di-
rect Current Side 554

1 -k Repairs on a Pitted Commut.ilnt. . 555

Manager (Jets Some Experience 555

Edge's Wiring Pointers .555

_ont Combined fins K:nglne and Air
Compressor .550

r^nglnes for Warship Propulsion 557

-'•I Engines for Rome 55H

f;nB Turbine Problem 558

f'lrmnnce of an Oil Engine Pumping
Plant .558

ITarllcnl l.ellprs:

Keg Tank Float . . . .Double Eccentric
Corliss Valve Setting. ... Poorly I)o-
slgni'd Hearing. . . . Flxe<l Eccentric
, . , . Condemns License I_iws ....
Painting Engine-room Floors ....
Cfimpresslon l'nneccssar.v. . . . Pislrm

Rod Parking Inc.ibs .'Ihiiperl I»

comollve Fireliox. . . . Ilomemflde In-
dicator Reducing Motion. ... Keyed
Piston linyo Trniibln 5.5n-.5<!I

I -mission U-llers:

'■•■nlrnl Station versus Isolated Plant

To Prevent Slnndplpe Freejiing

Potblyn. I'umii IXMtnr Mass

nchuselts License Laws and Ex-
aminers. ... Status of the Engineer
... Indlrntor DlaRTams Testi-
monial I.«>tters .502-5(15

' ''"rial 5n7-.50S

Kan Hyslem rs. Direct Radiation nnu

Connections of Range Boiler .175

Receiver Pressure

Receiver pressure is probably as often
discussed as any other question connected
with steam-engine operation. It is claimed
by many engineers that the load should
be equally divided between the cylinders
of compound engines, and that the re-
ceiver pressure which equalizes this dis-
tribution is the best. It is the cutoff on
the low-pressure cylinder which deter-
mines the distribution of the load between
the cylinders, the receiver pressure, and
to the extent to which it influences the
efficiency of the engine the cutoff on the
high-pressure cylinder. It is the cutoff
on the high-pressure cylinder which de-
termines the quantity of steam used by
the engine. This point is indicated ap-
proximately by the hight at which the
governor revolves. But the clearance, de-
gree of compression and the receiver
pressure modify the quantity of steam
admitted to the cylinder at each stroke.
Either compression or the receiver will
fill the clearance space with steam at the
corresponding pressure.

Without either clearance or compres-
sion the volume of steam admitted to the
cylinder up to the point of cutoff will be
the piston displacement up to this point.
With clearance, if the receiver pressure
could be made equal to the initial, no
steam whatever would enter the cylinder
until after the piston had begun to move
forward and thereby lowered the pres-
sure in the cylinder, and the volume ad-
mitted would equal the piston displace-
rnent.

Engines are not built without clearance
and in addition to the piston displace-
ment the clearance space must be filled
with steam at initial pressure and it is
here that compression may modify the
volume required from the boiler. If the
compression is carried to initial pressure
the clearance is filled with steam at initial
pressure and temperature and only the
volume of the piston displacement can be
taken from the boiler. If the compres-
sion is less than the initial the effect will
be equivalent to th.it of filling a portion
of the clearance with steam at initial
pressure, and this portion will be directly
proportional to the degree of compression.
From this it may be seen that a short
cutoff as indicated by the high plane in
which the governor revolves may admit
more steam to the cylinder at each stroke
than an apparently longer one, because
more steam is required to fill the actually
larger clearance caused by the lower

receiver pressure, and consequent lower
compression in the high-pressure cylinder.

In the above argument no account has
been taken of cylinder condensation.
About twenty per cent, of the steam which
is taken from the boiler is condensed as
it enters the cylinder to be reevaporated,
for the most part, only after the exhaust
valve opens. The lower the pressure in
the cylinder when the admission valve
opens the greater will be this condensa-
tion and the greater the amount of steam
admitted even for the same point of cut-
off and position of the governor.

While it may not in all cases be so, it
is, however, generally true that the higher
the governor revolves for a given load
the smaller the volume of steam required
for that load, and that receiver pressi're
which will carry the governor the highest
should be chosen.

Ik)iler EtHciencv

When the results of a boiler test indi-
cate an efficiency of eighty per cent, or
more, the calculations are usually car-
ried out to three or four decimal places
for at least two reasons: First, those
w ho make the test wish the accuracy of
the calculations to be so impressive that
the results will not be open to undue
suspicion; second, they do not wish to
risk the possibility of the efficiency fig-
ure being diminished by dropping too
many fractional parts.

.lust what boiler efficiency constitutes
the world's record we do not know. Oc-
casionally, an efficiency above eighty-four
per cent, is announced; in such cases
the majority of at least the unavoidable
errors made are probably in favor of the
boiler. An efficiency of eighty-four per
cent, is so close to the theoretically pos-
sible attainment that a higher figure
naturally engenders doubt as to its ac-
curacy.

Experienced engineers disagree as to
just how exact the results of a boiler test
may be made. Some contend that within
three per cent, of absolute accuracy is as
close as it is possible to bring them;
others are of the belief that within one
per cent, is not impossible. It seems safe
to assume that a large majority of the
ordinary eight-, ten- and even sixteen-
hour tests do not come within five per
cent, of absolute accuracy.

It is more difficult to approach accuracy
in a test with coal as fuel than with
oil or gas, especially in "short tests, say
under forty-eight hours, for if is quite

POWER

October IG, 1911

impossible to measure the depth of the
fire with any exactness and it is more
troublesome to measure the fuel ac-
curately. Where the boiler superheats
the steam the test results are likely to
be more accurate than where the steam
is given off in a saturated condidon, for
in the latter case the errors applying to
the calorimeter are brought in.

Of course, the personal element has
everything to do with the reliability and
worth of the reported results. The man
who conducts a test must be e.\perienced
and capable and his integrity must be
above suspicion; moreover, he must be
fair-minded enough to settle uncertain
points with absolute impartiality and not
allow his judgments to be colored by
his desire to obtain certain results.

In this issue will be found an account
of two boiler tests and the results ob-
tained. All of the circumstances sur-
rounding these tests are conducive to the
belief that the results are as nearly ac-
curate as could reasonably be expected.
The fuel was crude oil and superheated
steam was generated — two factors which
are in favor of close determinations —
the scales, thermometers, gages, etc.,
were painstakingly tested and one of the
boiler tests was conducted under the
scrutiny of Prof. W. F. Durand, who en-
joys eminence as an authority in engi-
neering circles and an enviable reputa-
tion for fairness and carefulness. The
reported efficiency of 83.43 per cent,
(the average for the two tests under
discussion I is a notable figure.

Power Plant Supply Analyses

No power-plant equipment is complete
until it includes the apparatus necessary
for the analysis of the three important
materials of consumption: coal, oil and
water. This apparatus, for the average
plant, is not necessarily either elaborate
or expensive. It may include only such
instruments as will answer the one or
more important questions that are of in-
terest to the operator regarding their
chief qualities. For a coal analysis that
will suffice for most purposes, such as
finding the content of moisture, volatile,
carbon and ash. a single graphite crucible
or on a pinch an iron ladle and the com-
mon platform scale are sufficient, as
small quantities of any substance may be
weighed on the beam of the scale.

In a turbine station where surface
condensers are supplied with sea-water
circulation the chief requisite so far as
water is concerned is that there shall
be no salt in the condensate, which is
returned to the boilers. Salt makes its
presence known, when burned, by an
crange-colored flame, and even a trace
of salt in the water is eastly found by
burning a single drop on the end of a
clean iron wire in the flame of a spirit
lamp or a bunsen burner. The nitrate
of silver test for salt is quite easily and

inexpensively made and has the advan-
tage of being much less delicate, for salt
must be present in a measurable amount
to be revealed by the silver test, while
with the burner test the slightest trace
of salt is shown distinctly. Percentages
in this case are not material, for any
appreciable quantity of salt at all is too
much.

In the matter of oil much or little
knowledge may be considered necessary.
But those qualities which most interest
the engineer are viscosity and acidity.
Viscosity is a term used to designate. the
comparative fluidity of oils and it con-
veys no information whatever unless the
instrument by which the results were
determined is known. The viscosity of
an oil is given as the number of drops
that will flow through a given orifice in
a given time at a given pressure and
temperature as compared with the flow
of water or of some other oil. There
are elaborate viscosimeters on the mar-
ket, but the mentally alert engineer need
not forego a reasonably accurate knowl-
edge of the viscosity of his oil because
the plant manager will not purchase an
outfit for his use. because a dairy ther-
mometer and a tin cup with a small hole
in the bottom may be made to give re-
sults closely approximating accuracy. It
is more often the man than the tools
which determines the value of any work.

State Regulation of Water
Rights

The law governing the appropriation of
water for hydroelectric or other power
development, passed by the California
legislature in April of this year, is now
in effect. The act is intended to sys-
tematize the State's water rights, and
place them under the jurisdiction of a
board of control at Sacramento.

The law provides that no appropriation
cf water for generating electricity or
electrical or other power can be made
for a period longer than twenty-five
years, with the -privilege of renewal of
license for a second term of like duration.
Its use is made subject to the right of the
State to regulate and establish all power
rates, and if appropriated for other than
power development, it cannot be used for
such development except under a sep-
arate and distinct filing.

It classifies as unappropriated all
water which, having been duly appro-
priated, has not been put to some use-
ful or beneficial purpose or leased for
such service, and any such water which
is not at this time in course of being
used with proper magnitude in propor-
tion to the work. Under a granted ap-
propriation, actual construction must
commence within six rHonths from date
and be reasonably prosecuted.

.Applications for water appropriation
must be made on blank forms supplied
by the board, with detailed informa-

tion. An application does not lose priority
of filing through any defect if it is pre-
sented again within thirty days after
rejection. Any rejection by the board
is to be made within six months, allow-
ing due time for investigation. The ap-
plication fee is ten dollars and the li-
cense for water appropriation costs one
hundred dollars. An additional tax is
levied, to be paid to the State annually,
of ten cents per theoretical horsepower
developed in excess of one hundred.

Evidently California has made a good
start in the right direction and if other
States would fall in line there would be
no need to fear the so called water trust
about which there has been a great deal
of agitation during the past year.

Engineers' Wages

Most general topics apparently travel
in circles, occupying the center of the
stage periodically, and. after being sub-
jected to much discussion, with perhaps
some gain to the cause, are relegated to
the rear to make way for some question
of newer interest. Such is the oft dis-
cussed question of "Engineers' Wages,"
utterances regarding which are now
audible from certain quarters.

It is easy enough to preach upon this
subject, but such preaching is apt to have
little if any material effect; it is like try-
ing to apply "absent" treatment to a
broken leg. And in spite of all, the fact
still remains that the engineers as a class
are underpaid.

From time to time we tkave pointed
out how an engineer may make himself
more valuable to his employer and much
has been accomplished by the various
engineermg societies toward advancing
the interests and raising the prestige of
the engineer. While this is a decided
step in the right direction, it is not the
whole solution to the problem.

Like many other lines of business, the
standard of compensation is largely fixed
by the supply and demand, and as long
as a certain class of employers can find
engineers willing to work at laborers'
wages they will continue to employ them,
regardless of the fact that more com-
petent men could be had by paying a
few extra dollars. The employers are
apparently willing to take the chances.

Closely allied to the subject of low
wages is the charge of "graft" so often
hurled at the engineer. Now, frankly,
we do not believe that five per cent, of
the engineers would accept graft, but
imfortunately the majority is often
wrongfully judged by the standing of a
very small minority.

It is safe to say that the greater part
of those who do resort to graft are to
be found among the underpaid. While
this is no justification of such practice,
it certainly is contributory to it, and the
raising of wages would certainly do much
toward stamping out the graft evil.

October 10, 1911

POWER

569

Fan System versus Direct
Radiation^'

Bv Ira N. EvANsf

From the following discussion the con-
clusion should not be drawn that any one
of the methods should be used to the ex-
clusion of the others as there are condi-
tions such as size, use, location and con-
struction, besides cost of installation and
operation, which may have an equally im-
portant bearing on the choice. When
the physical conditions are favorable, the
author will try to show the relative econ-
omy of each method.

When air is required for ventilation in
schools, office buildings and shops, the

•Cop.vrightfd. 1911. by lia N. Evaus.
■M'onsulting enginoer. heating and pi
l.^iC Broadway. New York City.

heating system in the form of direct sur-
face in the various rooms should be
capable of operation independent of the
ventilating system, although heat may be
supplied to both from the same source.
This point is well understood in school
work where the standard method for
economical operation is to heat the rooins
with direct radiation and operate the
blower to furnish fresh air at 70 degrees

sufficient tor the number ot occupants
during school sessions only. The dirttwi
radiation may be omitted in chnia'es
where the coldest known temperature 'S
above 20 to 30 degrees outside, reducing
the first cost without interfering with the
economy of operation.

A system of ventilation is rendered un-
necessary in many large shop buildings,
due to the large ratio of cubic conttntb vo
the number of operatives. When direct
radiation only is used in this class of
building, as the heated air has a teiidency
to rise in proportion to the difference
in temperature of the room at difterent
levels, the roof may be several degrees
higher in temperature than the floor, in-
creasing the radiation of heat througn the
roof to the outside. The difficulty of ob-
taining positions for coiis without inter-
fering with the machinery and trenching

Fic. 1. Ahra.ncement of Coils in Painiinc OtFAKiMtNi oh int Lackawanna Kailkoad's Kinlmanm bailors

570

POWER

October 10, 1911

for the returns in central portions of
shop buildings, is a serious matter.
Overhead coils are useless when placed
any distance from the floor, as the space
necessary to be heated of a high shop
. building is that section about 10 feet
from the floor. The leakage from doors
and windows all falls to the floor, making
the zone of greatest heat requirements
the coldest part.

The fan system of heating for all
classes of work is so generally under-
stood as to need no description as to its
arrangement in its general application.
The specific heat of air is about 0.24

initial temperature of the entering air to
the extent of the drop.

The low density and specific heat of air
render the boiler power in extreme
weather very excessive when the hot-blast
apparatus only is used for heating. The
operation of the fan in circulating the air
increases the natural leakage of the doors
and windows, requiring greater heating
capacity in proportion to the difference
between the initial temperature of the
entering air and the outside temperature.
This initial temperature varies inversely
as the amount of air circulated in pro-
portion to the cubic contents.

suits with a hot-blast system. Larger
apparatus with corresponding increased
first cost is the result.

Notwithstanding the above difficulties,
the flexibility of the hot-air system due
to the ease with which the change of
the temperature of the circulating medium
is effected makes it a desirable method
of heating in many respects. TTiis is
especially true when the fan heaters are
supplied from a general exhaust-steam
system operated at nearly a constant tem-
perature of 212 degrees. A wide range
in regulation to suit variations in the out-
door temperature may be had by shutting

Fig. 2. Biower System in Locomotive Erecting Shop

that of water and its volume about 780
times; therefore its capacity to convey
heat is limited as to distance and amount.
A comparatively few units of heat will
raise its temperature materially and a
reduction in temperature liberates a cor-
respondingly limited quantity of heat.

The radiation of heat from necessarily
large ducts is a serious factor, and, al-
though they may he entirely within the
space heated the loss by radiation occurs
at a disadvantageous point. It amounts
generally to about 10 degrees per 100
feet of length, necessitating a higher

In large shop buildings it is sufficient
to recirculate the air through the fan and
heater as the use of outdoor air would
make the operating expense prohibitory.
In high open buildings it is difficult to
make the heated air diffuse and come
in contact with cold walls and windows in
order to give up its heat. Its tendency
is to rise in proportion to the difference
in temperature of the entering air and of
the air contained in the room. This re-
quires the circulation of large volumes
of air in order to reduce the initial tem-
perature and to obtain satisfactory re-

off portions of the heater coils and vary-
ing the speed of the fan. Where a hot-
water system of distribution is employed
and the water temperatures are properly
regulated at the plant the same necessity
of manipulating the heater valves and
speed of fan does not exist.

Many fan systems in industrial plants
are in reality live-steam propositions a
large portion of the time. The engine
operating the fan furnishes sufficient ex-
haust steam to heat the building in mod-
erate weather, rendering the exhaust-
steam connection from the main engines

October 10, 1911

POWER

571

unnecessary except in extreme weather.
According to data on hours taken from
a previous article the period of exhaust
operation would be less than 265 for the
whole season.

Fan engines have a high steam con-
sumption and a reduction in speed in-
creases the rate per horsepower-hour
proportionately. On the other hand, when
the fans are operated by motors con-
nected with the main plant the heating
system becomes inoperative nights, Sun-
days and holidays if the main engines
are not running. In a plant embracing
several buildings, it would be economy
to install an auxiliary unit for this pur-
pose in the main engine room.

The combination of heating and ventila-
tion in a fan system is commonly advo-
cated by manufacturers of that type of
apparatus to reduce the first cost, but the
combination of a direct-heating system
with the fan arrangement is seldom con-
sidered.

The line is sharply drawn between the
recommendation of a blower system on
the one hand and that of direct radia-
tion on the other. This is due in part to
business conditions, the blower manufac-

10.000

requisite size of heater and fan to ac-
complish results and lack of knowledge
of the data on the design of a proper
fan heater to meet the varying require-
ments of water temperature.

On account of the conditions just
enumerated, several shop plants were de-
signed to be heated from a central plant
with forced circulation of hot water,
utilizing the steam from the main en-
gines under partial vacuum. The method
of heating adopted for some of the build-
ings was a combination of direct radia-
tion on the outside walls sufficient to
counteract the loss of heat through the
glass and wall areas, and a blower system
recirculating the air over hot-water coils;
the capacity of the components of the
combined system being about 50 per cent,
of what would be required if either sys-
tem were used alone. The direct radia-
tion was sufficient to maintain the proper
temperature without the aid of the fan
system at night, and when the weather
outside was above 35 degrees. A higher
temperature of water was used at night
and a slightly lower temperature in the
rooms. This arrangement allowed the
fans to be operated by motors as they

J> 4000

5 10 15 20 25 30 35 40 45 50 55 60

Oj+;.ide Tempera+ure

Fic. 3. Steam Consumption Curves for the Various Systems

furer selling his product direct to the
owner, when possible, without ducts or
steam piping, and the steamfitfer proper
being obliged. ..i case the fan system is
adopted, to buy that portion of the ap-
paratus from his competitor.

Due to the comparatively low tempera-
tures of water required for condensing
conditions on a hot-water systeiti. blowers
have seldom been used on account of the

were not necessary at the times when the
main engines were inoperative. The live-
steam heater in the boiler room was used
for night heating with a slightly higher
temperature for the circulated water when
the engines were inoperative and with
the reduced heating surface in the build-
ings rendered the cost of night and Sun-
day operation a minimum. All water
pipes and coils, as well as all trenches.

were eliminated from the central por-
tions of the buildings.

The fans, heaters and motors in all
cases were supported in the roof trusses
overhead, and arranged to take the hotter
air at the roof level and blow it through
the heaters and main distributing ducts
in the central portion of the building to
the drops at each column where the air

0

dlowerS^

^f C •

L-A.

CuneD

Combination Svsteni
10950 M'S)l7T^f/86l

I I I

Curved \l545 Hours

-CrvcB' 2646 ' —

Total [4191 -

Fig. 4. Chart Showing Relative Oper-
ating Costs

was delivered to within 8 feet from the
floor; see Fig. 2.

It was found that the air diffused much
better and the efficiency of the direct
radiation was increased when the fan
was operated. The high peak in extreme
weather due to the use of a fan system
alone was reduced and, although more
steam was required at times than for di-
rect radiation, the system operated on a
lower temperature which enabled a higher
vacuum to be carried on the main engines,
and thus increased the total economy of
the plant.

The Kingsland shops of the Lacka-
wanna railroad afford an opportunity to
compare the results of the direct system
with that of the combination system as
some of the buildings were equipped with
either system on the same hot-water cir-
cuit.

The shop plant comprises about twelve
buildings for the repair of cars, locomo-
tives, etc. These are all heated and
supplied *'ith power from a central plant
which contains six Stirling boilers ag-
gregating 1500 horsepower, three Buck-
eye compound-condensing engines, two
of 350 kilowatts capacity and one of 2,50
kilowatts, with the usual auxiliary ma-
chinery. There are also two air com-
pressors requiring about 300 horsepower.
All of the units have two separate ex-
haust connections to two mains under the
floor, with floorstand valves. Any unit
may be exhausted into the main connect-
ing the large exhaust heater under partial
vacuum for heating, or to the condenser
direct with full vacuum without shutting
Ihc engine down.

The vacuum on the exhaust heater is
regulated by a valve in the return be-
tween the heater and the condenser. Two
automatic relief valves are used; one
forming a bypass on the condenser be-
tween the two exhaust mains, and the
other is installed at the point where the

572

POWER

October 10. 1911

main exhaust enters the heater. The
heater connection is taken from the out-
board exhaust main inside the second
relief valve.

The live-steam heater is connected with
a gravity return with an injector tee di-
rect to the boilers as heretofore described
lor night heating, when the main engines
are inoperative. This arrangement gives
about 10 to 15 per cent, greater economy
than when the condensation is handled
bj traps, pump and receiver or other
methods. The boiler steam is surrounded
in the; heater by the circulated water and
except for the slight radiation from the
efficiently covered shell any loss by re-
leasing the pressure from the condensa-
tion is impossible. Both water and steam
circuits are hermetically sealed and what
heat is not passed into the heating sys-
tem must go back to the boiler in the
condensation under nearly the same pres-
sure and temperature as the boiler steam,
only the latent heat being utilized.

This is in direct contrast to the method
of reducing the boiler steam to nearly
atmospheric pressure and handling the
condensation by a pump or other method
involving a release of pressure and loss
of vapor and condensation. If the boilers
were operated at 100 pounds pressure,

from 70 to 210 degrees, or 140 degrees
on each pound so lost. This might amount
to much or little dependent on conditions,
but with the arrangement recommended
such losses are impossible.

These losses are due largely to the
conditions of practical operation and in
many cases would not appear in a theo-
retical discussion. They may be con-
siderable when the vacuum pump of an
exhaust-steam apparatus requires a
stream of injection water as large as
1'4 inches, to cool the return, as this
is entirely overflow with reference to the
heating system itself.

If a live-steam heater of a hot-water
system is connected with pumps or traps
its economy is destroyed and the live
steam may just as -veil be turned directly
into the exhfust heater.

The pumping apparatus of the hot-
water system consists of two 8-inch De
Laval turbine pumps connected so as to
operate singly or in series, one direct-
connected to a motor and the other to
a DeLava! turbine of the gearl&ss type.
The mair water pipe is 8 inches in diam-
eter, reducing as branches to the build-
ings are taken off, with separate returns
to the header in the engine room. The
mill building, carpenter shop, large loco-

Arr.\nce.ment of Pit and Colu.mn Coils [N the Loco.motive
Erecting Shop

or 337 degrees, and the steam were used
at nearly atmospheric pressure, or 210
degrees, with the return about 170 de-
grees, there would be the following
losses: A loss of 40 B.t.u. on each pound
of steam used for heating, the loss due
to wiredrawing in the reducing valve, the
possible loss of the heat in the exhaust
steam of the pumping apparatus. In ad-
dition all water overflowing or lost through
traps or in vapor would have to be raised

i-iotive shop and two passenger-car shops
are heated by the combination system
of blowers and direct-radiation system
to 60 degrees in zero weather. The
paint shops, lavatories, office building,
paint and oil storage, and paint and
coach annex are heated by direct radia-
tion only; the paint shops and offices to
70 degrees and the remainder to 60 de-
grees.

In Fig. 1 is shown the arrangement of

coils in the paint shops. Fans were not
used here on account of the dust being
stirred by the rapid movement of air and
settling on the varnish. These shops were
kept at 70 degrees night and day and the
problem was not so much a question of
heating as of reduction of the relative
humidity to give a proper atmosphere for
drying. The heating surface is in the

~^pph

X

zrrrfL rr^rrp

rrrrrr tn

\Vr\^ WrV?^

Fig. 6. Window Coils in Paint Shop

form of two eight-pipe coils placed ver-
tically on each column with an overhead
supply and the return pipe in a floor
trench. The side walls were provided
with six- and eight-pipe coils around the
windows, as shown in Fig. 6.

One side of the building opened with
large sheet-iron doors on the transfer
table and eight-pipe double coils were
placed vertically on each pilaster between
the doors. In the floor near these doors
one trench is provided with open gratings
with several 2'_.-inch return pipes to
counteract the draft and air leakage from
'this source. The heating surface was
about one square foot for 125 cubic feet
of space and at 70 degrees it gave satis-
factory results.

The windows in the lantern were ad-
justed to meet conditions so a slight up-
ward movement of air was created from
floor to ceiling, at the same time curtail-
ing the number of opened windows so
as to prevent a down draft. The air was
supplied mainly by the door and window
leakage, which was sufficient in this case
as none of the doors was tight. The large
amount and vertical position of the heat-
ing surface furthered this method of pro-
cedure and gave a satisfactory drying
atmosphere without the dust attendant on
the use of a fan system or the unsanitary
trenches to contain the heating surface
in the floor, which was the scheme origi-
nally proposed. Excessively high tem-
peratures were unnecessary to accomplish
results and the plant was operated often
in damp weather.

In the other buildings heated by direct
radiation only, the surface was in the
form of coils or radiators distributed in
the regular manner on the outside walls
under the windows with an overhead sup-
ply r^ain. The return pipe was exposed
on the side walls under the coils and
trenched whci passing under doors.

In the high ^hop buildings the com-
bination system \vas used. Fig. 2 shows
the arrangement of ducts, etc.. in the lo-
comotive-erecting shop. The air was re-

October 10, 1911

POWER

573

circulated over a hot- water coil of 1-inch
pipe built up of cast-iron bases with el-
bows and nipples. A complete air change
was made once in 30 minutes, and the
direct radiation, placed on the outside
walls only, was proportioned on the
ratio of about 1 square foot to 300 cubic
feet of space. The water circulation
remained on the fan coils continuously
whether the blowers were operated or not.
The fan motor was controlled by a
switch at the floor and the only operation
necessary to start the entire fan system
was to throw the switch. The type of
coil used for heating the air was made up
in sections of 1-inch pipe and hoisted
into place as a single radiator. The
largest section contained 3000 lineal feet
of pipe, arranged as the regular type of

ing through the doors from the transfer
table. The projection of the pipes from
Ihe sides of the pit rendered the fittings
and hook plates liable to be broken by
heavy weights. To obviate this difficulty
the concrete was recessed on each side
as shown, and the hook plates, reversed,
v ere fastened to the side walls by heavy
iron cleats, arranged so as to make the
side of the pit and the pipe coils flush,
with no projections. This arrangement
proved very satisfactory, and is recom-
mended for roundhouse work when sup-
plemented with a hot-air supply. On
the side walls of the machine-shop por-
tion of the building the window coils
were made and connected as shown in
Fig. 6.

The curves in Fig. 3 show the relation

without involving the transmission losses
from the main plant or the steam con-
sumption of the engines when using ex-
haust steam; the general relation would
be true whether exhaust or live steam or
hot water were used.

Table 1 gives all the data for Figs. 3
and 4, the number of hours being taken
from a table in the September 12 issue, as
in Table 2.

Curve A. with pounds of steam as
ordinates, and outside temperatures as
abscissas, gives the steam consumption
per hour of a blower system. The data
are taken from Sturtevant's "Heating and
Ventilation." This involves an air change
every 14 minutes and 140 degrees as the
temperature of the entering air necessary
to hat a building to 70 degrees in zero

lABI.E 1. COMP.\U.\TIVI-: D.\TA OX Bl.OWlOU SVSTKM. DIUKCT UAl»I.\TIOX AND TIIIO COMHl NATION SVSTKMS

ni.nwKR .<vsrE\r

l.n.K.T UAOIATIOS

OutsidP

Temperature,

D-'grees F.

TempiTature
Factor

sieain per

Hour, Pound-i.

Curve A

Hour.f

Steam per
Season, Pounds

A verage
Water
Temper-
ature.
Degrees F.

Vacuum

Teinp.T-
aliire Dif-
ference of
Pipes ami
liooin

Hours

.Steam per

Honr.

Pounds.

Curve D

Steam p.-r
Season. Pounds

0-10
10-20
20-30
30-40
40-.50
50-60

0 S5
0 65
0 47
0 ■.!
0 2
0 1.-.

fl,282
7, DOS
5,132
3,276
2.184
1,63S

66

264

S29

1.471

1.131

1.27.-.

612.612
l.s.-,o,112
1.2.-. 1.42S
I.'-IX.'.IM
.'. 1711,104
J.OSS.150

205
195
185
175
160
1.35

3'

12''

135
125

)1.-.

10.-.

'.Ill
6.-.

66
264

.S2il
1,171
1.131
1 .275

4.131
3,,S25
3,519
3,213
2,754
1,98!)

272.646
1,009,800
2,917,251
4.726,323
3,114,774
2. .535,975

Tolal.x

.-..036

16,094,702

. , ,

.-..(136

14,576 769

('..\

mxvn

,N SV.IKM

(Da.v HeatinK)

(■

o.MniNATiON System (NiKht Heating)

Ik-

m

c -

5S

=ei

1

55-

So
7«

'"' C 3

So

w

ai

K

5.5

iy

>

^^

■i i'^

■ri5

£a

^■i

f:

-

0-10

19(1

4

120

50

10

1.944

3,9(WI

5,844

58.140

215

155

3.348

56

1.87,488

10-20

180

1(1

no

10

.•.0

1 .782

3.120

4.902

215,100

205

145

3.132

214

670,248

JO 30

170

IK

KKI

.30

20.1

1 .620

2.340

3,960

81 l.,S(l(l

195

135

2.916

624

1.819,584

111 III

i.'iO

14

80

2.-|

.-.00

1 .296

l.'.I.Ml

3,246

1. 623.01 10

1.811

120

2.592

971

2,516.732

1II-.-.II

IGO

20

9(1

3.50

1.94 1

1.914

080.1(1(1

1611

100

2,100

781

1,686,960

50- 60

140

22

7(1

13(1

1.512

1,512

6.'.. I.I 60

I III

811

TolaN

1.545

4.068,900

2,6 16

6,.S81,012

blower coil but modified to relieve the
air automatically and give a positive
water circulation.

Considering the efficiency of transmis-
sion of pipe coils over cast-iron radiator
sections, the labor of assembling and
making the latter tight, it is the writer's
opinion that the pipe coils will prove
the more satisfactory, notwithstanding a
slightly increased cost. Where weight
is an item of consideration the pipe coil
has the advantage.

The arrangement of coils in the pits
and on the columns of the locomotive-
erecting shop is shown in Fig. 5. The
main supply is placed overhead in Ihe
trusses supplying each coil on the col-
umn, the return from these column coils
forming the supply to the pit coil, which
later was connected into the main return
in the floor trench.

The locomotive shop was of the regu-
lar design, with pits in each track enler-

of the hourly steam consumption of a
blower system, a system of direct radia-
tion and a combination system. The
data shown in Table 1 were obtained from

Combina-

lionSVHlem

Nuhl

Operation,

Deeri-cs

Hours

0-10

.-lO

10 20

214

20 30

624

w-io

071

i(t-ao

781

.-IO-60

Conliniioiis

Comliina-

Operation
of Hlouer

lionSvHtein

Day ()pi ra-
Mon, Houn.

and Direri

Kail lat ion

10

06

.Ml

204

20.5

829

.MKI

1171

3S0

1131

430

127.^

experience on several Installations where
hot water was u«cd. A log was kept for
several months during the heating sea-
son, so the quantities given are fairly
accurate. The curves arc worked out
for the actufll steam required for heating

weather. If the air is recirculated the
rise is 70 degrees and if outdoor air is
used it would be 140 degrees in zero
weather. In the book referred to a series
of curves give factors showing the per-
centage of this amount of heat required
in weather above zero, regulation being
effected either by reducing the speed of
the fan or by lowering the temperature
of the entering air by shutting off part of
the heater coil. For this comparison the
building is figured to be heated to 70 de-
grees, the air is recirculated in each case
and continuous operation is intended. All
fan-heating guarantees arc based on con-
tinuous operation. The building taken as
an example has 2,080,000 cubic feet of
space and is the passenger shop at Kings-
land with the apparatus changed to give
70 degrees instead of (io degrees. A
change once in Ifi minutes gives 130,000
cubic feet of air at 140 degrees as the
amount required in zero weather per min-

574

POWER

October 10, 1911

ute. The factors and other data are given
in Table 1 and plotted as described; 50,-
000 cubic feet is the amount of air one
pound weight of steam will raise one de-
gree. Thus

ing the same quantities as before, would
require

65,000 ,

50,000

X 60 = 78 pounds

130,000

X 70 X 60 = 10,920 pounds

50,000

of steam per hour are required in zero
weather. This quantity multiplied by the
factors in each case gives the data for
curve A, Fig. 3, and Table 1. The hours
for the different periods for the whole
season were determined as shown in a
previous article.

To operate this fan with an engine, al-
lowing for friction and other losses, will
require approximately 100 horsepower,
which at 50 pounds per horsepower-hour
would mean 5000 pounds of steam per
hour, plotted on line E, Fig. 3.

Curve D shows the requirements for
direct radiation applied to this building
•from data of the paint shop, which is
practically part of the same building. A
transmission is used of 1.8 B.t.u. per
hour per square foot per degree differ-
ence between the temperature of the
pipes and the air of the room heated to
70 degrees.

The direct surface will be taken at 17,-
000 square feet, or at the same ratio
(1:1251 as for the paint shop for 70 de-
grees, with continuous operation for 5036
hours. Thus

( 17,000 X 1-8) H- 1000 = 30.6 pounds.
of steam per hour per degree difference
in temperature between the pipes and the
room gives the data for curve D,
Table 1. The latent heat is taken as 1000.

Curves B and B' were plotted from
data on the combination system of direct
radiation on the outside walls and a
blower system recirculating the air. The
water and air temperatures shown in
Table 1 are the actual readings on sev-
eral jobs with the same proportion of
heating surface. An air change of once
in 30 minutes requires 65.000 cubic feet
of air per minute, and tne direct radia-
tion totals 9000 square feet or one square
foot to 230 cubic feet of space.

The power required to operate the fan
was about 50 horsepower, which at 35
pounds of steam per horsepower-hour
would mean 1750 pounds. This was
based on a 40-horsepower motor operat-
ing on current from the main engines,
including all losses — line M, Fig. 3.
Steam for fan operation is disregarded
unless it can be considered as exhaust
steam used for heating. It has been in-
dicated in Fig. 3.

The transmission for the direct radia-
tion and steam rate for raising the air
temperature are taken as before and
shown in Table I under combination sys-
tem. Thus, as before,

(9000 X 1.8) H- 1000 = 16.2 pounds.
per hour for each degree difference be-
tween the air of the room and the pipes
when the fan is operative. The air, us-

cf, steam per hour for each degree rise
in temperature. The total number of
hours of day operation is 1545 from the
table previously referred to. The sum
of the pounds of steam for the direct
radiation and the air supply for each
10-degree period form the ordinates for
curve B, Fig. 3 and Table 1.

The night operation and the last two
items in the column of total steam for
combination day heating. Table 1, when
the fan is inoperative, include the fan
coil of 3000 square feet as direct radi-
ation, making a total of 12,000 square
feet. There is a gravity circulation of
air through the ducts and coil when the
blower is shut down sufficient to warrant
this method of figuring.

The direct radiation under these con-
ditions would require with the same
transmission

(12,000 X 1.8) -=- 1000 = 21.6 pounds
of steam per hour per degree difference
of temperature of room and pipes.

In the case of the night heating the
room is allowed to cool somewhat be-
low 70 degrees. The transmission is
taken at a room temperature of 60 de-
grees and the system discontinued be-
low 50 degrees outside temperature.
This gives a higher steam consumption
for a given amount of surface than if
70 degrees were used. The hours for
sight heating total 2646.

The fan system shows high economy
in moderate weather, but the peak of the
load in extreme weather shows a great
increase in the necessary boiler power.
The ordinates of cur\'e A, Fig. 3, would
be doubled if outdoor air were used. The
high peak is due to the high temperature
and large volume of air increasing the
building leakage in extreme weather. De-
creasing the volume requires a higher
temperature of air and its tendency to
ascend to the roof level is greater, en-
dangering the efficient operation of the
system. At the same time this is one
way of reducing the first cost of a blower
system by installing smaller apparatus.
Decreasing the size of ducts and increas-
ing the velocity of air is another method,
but this increases the power necessary
to drive the fan.

When the first cost of an apparatus is
the main object rather than operating ex-
pense, it might pay to operate the fans
with engines, condensing the main en-
gines and using live steam on the fan
coils in conjunction with the exhaust from
the fan engine. This would give a very
flexible plant and except for the high
peak a small percentage of the time and
the fact that the exhaust from the main
engine could not he used would be
nearly as economical in use of steam as
a hot- water system operated with live

steam. In industrial plants operating
days the exhaust is only available 30 per
cent, of the time against 70 per cent,
when live steam is required in any case.
The first cost of this plant with small
high-pressure mains makes it very at-
tractive in some cases as there would be
plenty of pressure to remove the air
and return the condensation.

In arranging a fan system to operate
on a forced hot-water circulation system.
Curve A would remain the same but the
fans and heater would have to be in-
creased in size to enable the tempera-
ture of the water to be reduced within
the limit of the exhaust steam when taken
under partial vacuum from the main en-
gines.

Some high shop buildings have been
arranged with a hot-blast system for
heating in the basement with under-
ground ducts discharging at the floor
level. The radiation losses from under-
ground ducts are very great and if the
air is recirculated through gratings in the
floor, the arrangement is apt to be un-
satisfactory. The warmer air will rise
to the roof to stay, and the air supply
to the fan will probably be the leakage
from open doors and windows. This
rush of colder and heavier air over the
floor to the fan inlet will tend to make
the working zone of the building uncom-
fortable when the apparatus is operated
at its greatest capacity.

In curve D note the reversed shape for
direct radiation. This is caused by the
humidity of the atmosphere which ps
maximum at about 30 degrees outside
temperature when snow is at the point
of melting. This humidity would be the
determining point between 25 and 35 de-
grees outside temperature whether the
•fans on the combination system should
be operated or not, as the dampness
would cause a chill even when the radia-
tion might be at the proper water tem-
perature for this outside condition.

This humidity within the building would
disappear immediately on starting the
fans.

The cost of operating the fans on the
combined system is about one-half that
of the blower system and the peak is also
materially reduced. The use of the di-
rect radiation at night and eliminating
the fans in moderate weather make these
periods a minimuir for operating expense.
The maximum temperature of the air on
the combined system is not over 120 de-
grees in zero weather and 50 per cent.
in amount as required tor the hot-blast
system. This combination allows lower
water temperatures and higher vacuums
to be carried on the main engine, as
shown by Table 1. For a temperature
of 0 to 10 degrees the direct radiation
requires 3 pounds back pressure while
the combination system shows 4 inches
of vacuum.

With the combination system it is pos-
sible to raise the temperature of the

i

October 10, 1911

POWER

575

building quickly as soon as the exhaust
is available in the morning as the ducts
are full of warm air due to the fan coil
being in continuous operation. This en-
ables the heating in the morning to be
done by exhaust steam rather than with
live steam without appreciably increas-
ing the water temperature and reducing
the vacuum as would be the case with
the other two systems.

A study of the curves in this and in
previous articles will indicate that many
systems of heating by direct radiation,
on low pressure or vacuum, are inade-
quate to give a comfortable temperature
in extreme weather unless a prohibitive
back pressure is produced, in order to
raise the temperature of the heating sur-
face. Therefore the buildings are cold
during the few hours of extreme weather
or are overheated in moderate periods.

The same is true where the blow-er sys-
tem is used without direct radiation, al-
though overheating in moderate weather
is a more common experience and un-
doubtedly due to carelessness in not shut-
ting off the heater coils.

The hot-water system of circulation en-
ables the main engines to be operated
more economically under condensing con-
ditions and the radiation can be regulated
by changing the temperature of the water
at a certain point in the engine-room.
Where the direct radiation, however, is
limited, as in the combination system on
low-pressure steam, there would not be a
very great change in the steam consump-
tion of the direct radiation; see curve B'
under the combination system. Table 1.
The main regulation would be in the fan
system.

The conclusion would be drawn that
the major portion of the saving in Fig.
4 outside of the engine question, could
be made on any blower job by adding
direct radiation to be operated on live
steam, nights and Sundays, or 70 per
cent, of the time, and reduce the speed
and power of the fan one-half, shutting
off a portion of the fan coil and only
operating the latter by motor 25 per cent,
of the time when exhaust steam was
available from the main engines.

Where a plant is equipped with direct
radiation part of the heating surface
could be removed and a fan system as
described added to make up the differ-
ence and a corresponding saving would
be effected.

tn the case of additions to a plant,
this method would enable extensions to
be made and sufficient exhaust steam
would be available to the extent of the
saving.

In Fig. 4 the total areas represent the
pounds of steam per season, or cost of
operating the four systems. The ordinate
in each case is the average pounds of
steam found by dividing the total amount
per season in Table 1 by the total hours.
At 17 cents per 1000 pounds of steam
(from a previous article based on S3 per

ton for coal and nine pounds of evapor-
ation) the costs are found to be as fol-
lows:

Direct radiation, low-prf>,ssurp steam, 21'2'"

Ccurv» P) $:i7i;7

Blower system, curve A 2736

Direct radiation, hot water, curve D 2I7S

Combination system, curves B and B*. . . . 1S61

The system of direct radiation would
cost about the same as the blower system
when all items of flues and steam piping
were included. The combination system
would cost not over 15 per cent. more.
The two points are again emphasized,
that the system which can save nights
by varying the temperature of the medium
to suit outside weather conditions is the
one which will show the greatest econ-
omy; also, that the saving due to using
exhaust steam is only incidental due to
the few hours of operation in the ordi-
nary plant. The introduction of two
shifts, night and day, would change the
whole aspect of the problem and increase
the importance of exhaust-steam op-
eration. It must be understood that
these savings are indicated for live steam

I'omliination sys
lem over direct
steam. 212°

Combination sys-
tem over blow-
er system

Combination sys-
tem over direct
radiation, hot
water

Direct radiation,
hot water, over
direct sleam
212 dei^recs

Direct radiation
hot water, over
blower s.vstem |

Blower system
over direct
steam 212°. . .1

ncinal on

Which

Saving Pays

15 Percent.

per Year

2,.iOO
!i.8,-?0

H.fiOO
1 .720
G.UOO

only and that the true saving on the plant
could not be determined until these curves
of operation are combined with the con-
ditions of engine operation as discussed
in a previous article.

Line P shows the steam consumption
of a low-pressure steam system with the
medium at 212 degrees and all surface
turned on. The hours of operation may
be curtailed due to overheating, but the
ccneral custom is to open doors and win-
dows, thus increasing the cost for steam.
Many large plants shut down nights,
using high-pressure steam a few hours
in the morning to heat up the buildings
before the engines are In operation, but,
except for labor, there is no saving in
this method.

The water circulation relieves oper-
atives of the necessity of going to each
building to shut off fan coils or radiators,
which would have to be done if economy
were desired.

With the reduction of boiler power at
the peak load and a more economical

vacuum on the main engines, the combin-
ation system will show a handsome sav-
ing over any increased cost.

The data in Table 3 show the amount
of money which it would be policy to
spend to obtain the advantages of sav-
ing of one system over another and
pay 15 per cent, interest and deprecia-
tion on the investment.

LETTER

Connections of Range Boiler

I think Roy V. Howard, whose letter
appears in a recent issue, is mis-
taken when he states that it is the usual
practice to connect the discharge pipe
from the heater to the side hole in a
range boiler. As for his statement that
the hot-water pipe from the heater is

Arrangement of Heating Boiler

usually connected to the bottom of the
reservoir, he is certainly making a mis-
statement, no doubt unintentionally. I
have seen hundreds of heaters connected
to reservoirs in private houses, public
buildings, factories, etc., both in Canada
and in the United States, during the past
25 years, and I have yet to see one sys-
tem with the discharge pipe from the
heater connected to the bottom of the
reservoir. If a man attempted to connect
a system in this manner he would show
himself to be entirely ignorant of the
first principles of hot-water heating.

I agree with your correspondent that
many heater discharge or circulating
pipes, especially in private houses, were
at one time usually connected to the
side hole about half-way up the range
boiler, the cold water going to the heater
from the bnitom of the range boiler. The
usual and proper way to connect up a
water heater is shown in the accotnpany-
ing illustration.

.lA,Mr<; E. NoBi.E.

Toronto, Ont., Can.

576

POWER

October 10, 1911

An Unusual Pumping Set

There has recently been installed by
the West Boylston Manufacturing Com-
pany in their cotton mill at Northampton,
Mass., a combination pumping and elec-
tric-generating set which embodies some
unusual features. The unit consists of
a 75-horsepo\ver Terry steam turbine di-
rect connected to both a 30-kilowatt Diehl
direct-current generator and an 8-inch
double-suction Jeanesville pump. The
generator is situated next to the turbine
with the pump connected beyond.
Flexible couplings are employed be-
tween each two machines so that it is
possible to cut out the pump and run
the generator alone. The conditions are
such that no occasion arises for running
the pump without the generator, which ac-
counts for the tandem arrangement.

The pump is employed in circulating
the hot water of the mill-heating sys-
tem, while the generator furnishes ex-
citation for the main generators which
furnish the power for tlje mill motors

formation regarding water-power rights
instituted before the adoption of the
State water code and water-power tax
law of 1909, applying only to such plants
as have appropriated water to advantage-
ous use prior to May 22, 1911.

The law requires that all such plants
file statements with the State engineer
by January 1. 1912, giving complete in-
formation of the extent of the claim of
water appropriated. Commencing from
that date, the following graduated fee
becomes due and must be remitted aii-
nually to the State: For each theoretical
horsepower up to and including 100, ten
cents: from 100 to 1000, five cents; in
excess of 1000, one cent. This tax be-
comes a lien upon the plant through non-
payment, and is collectable with propor-
tional additional sum as penalty by the
attorney-general.

The fee is waived where the total
claim does not exceed 25 horsepower,
provided a statement has been filed, and
in cases where the water is appropriated
for development by the United States,

Tlrsi.ne. Pu.mp and Generator Unit

during the day. .At night, the generator
is switched over onto the lighting circuit
of the mill and thus the load on the tur-
bine is a 24-hour one at practically all
seasons of the year. During the winter
it is necessary to run both the generator
and pump at all times. In the summer
as soon as the heating load goes off, the
pump is disconnected and the generator
operated alone. This set runs at 2600
revolutions per minute and the turbine is
operated noncondensing, the exhaust be-
ing used in the summer for boiler feed
and in the winter for heating the water
of the hot-water heating system.

Oregon Water Power License
Law

The law for the regulation of water-
power appropriation in Oregon, known
as the Water- Power License Act, passed
during the recent session of the legisla-
ture, has become effective. It is pri-
marily for the purpose of securing in-

the State or any municipal corporation.
The sum derived from this law will be
applied to a general survey fund for
State h\draulic-engineering work.

Historic Enfrine Sold for
Scrap

One of the largest transactions in sec-
ond-hand machinery in Chicago in many
years was recently reported by the Iron
Trade Review. The Pullman Company
sold to the Oakdale Iron Company, Chi-
cago, 23 old engines, making about 30
carloads in all. In this purchase made
by the Oakdale Iron Company, there
was included a large Corliss engine that
was exhibited at the Philadelphia Cen-
tennial in 1876 and was used for many
years at the Pullman Company's works.

Thousands of people have seen this
engine in operation, which, although
rated at only 1400 horsepower, weighed
over 650 tons. The engine will be re-
moved to the yards of the Oakdale Iron

Company at Ninety-first street and the
Belt railway, where it will be broken up.
Many of the parts of this engine will be
sold for use again and the rest will find
its way to the scrap pile. This no doubt
is one of the largest transactions in this
line in Chicago since the world's fair
material was sold. It has been suggested
that this engine ought to be preserved
intact in the Field museum, as the Pull-
man Company might donate it in the
interests of science instead of selling it
for scrap.

BOOKS RECEIVED

Power Plant Testing. By James Am-
brose Moyer. McGraw-Hill Book
Company, New York. Cloth; 422
pages, 6x9 inches; 271 illustrations;
tables: indexed. Price, S4.

Practical Thermodvna.mics. By For-
rest E. Cardullo. McGraw-Hill Book
Company, New York. Clotjj; 411
pages, 6x9 inches; 223 illustrations;
tables; indexed. Price, S3.50.

Machine Drawing and Sketching for
Beginners. By J. H. Robson. D.
Van Nostrand Company, New York.
Cloth; 196 pages. 5.\8 inches; 314
illustrations; indexed. Price, S2.

The Design of Static Transfor.mers.
By H. M. Hobart. D. Van Nostrand
Company, New York. Cloth; 174
pages, 5'_x8'_^ inches; 101 illustra-
tions; tables: indexed. Price, S2.

Direct and Alternating Current
Manual. By Frederick Bedell. D.
N'an Nostrand Company, New Yor!:.
Cloth; 360 pages. 5'4x8'S inches;
illustrated; tables; indexed. Price,

Electric Traction and Trans.mission
Engineering. By Samuel Sheldon.
D. Van Nostrand Company, New
York. Cloth: 307 pages, 5'4x744
inches; 127 illustrations; tables; in-
dexed. Price. S2.50.

Electric Central Station Distribu-
tion SvsTE.MS. By H. Barnes Gear
and P. Francis Williams. D. \'an Nos-
trand Company. New York. Cloth;
347 pages, 5'ix8'4 inches; 139 il-
lustrations; tables: indexed. Price,
S3.

PERSONAL

H. W. Deininger, formerly Iowa rep-
resentative of the Globe Machinery and
Supply Company, has accepted the posi-
tion of general manager of the Sac City
Electric Company, Sac City, Iowa, suc-
ceeding R. W. Richardson, who goes will"
Byllesbv & Co., at St. Paul, Minn.

Vol. 34

NEW YORK, OCTOBER 17, 1911

Nn. 16

WHEN the political spell-binder appeals
to the honiy-handed son of toil
for his support in the near-by elec-
tion, he prates earnestly of the dignity of
labor. But nobody thinks of the engineer,
for no comprehension of the importance of
his work in modem industry has entered the
public mind.

By many he is regarded as a necessary,
unavoidable evil in greasy overalls, and by
others as a man with a "soft" job, whose
hardest work is to turn on the steam or watch
the wheels turn around.

In the great majority of cases the engi-
neer's work is solitary', and the problems that
come to him under sidewalks, in close, hot,
illv ventilated basements and in all isolated
plants have to be solved alone, and often
without a moment's hesitation.

Steam engineering is not an exact science
that can be taught from textbooks, but in
every plant, from the little water-tank pump-
ing station with its single boiler to the great
central plant with tiers of boilers and engines
developing thousands of horsepower, dilTcrent
conditions obtain.

Fuel and feed water, steam jjressure and
character of the service rec|uired, electric
light, perhaps for a few hours, or it may be
power for the entire year without a sto]) of
one second; these and a thousantl other
forms of engineers' service arc his to give,
and, when it is realized that he meets every
question in the operation of his plant alone,
some idea may be had of what an all-roimd
man a real engineer must he, and of his

more than ordinary gifts in mechanical ability
and fertility in resource.

His importance is evidenced by the pages
of mechanical and technical publications
loaded with advertisements of instruments
and appliances that he alone uses.

More books and papers are published for
him than for the man of any other trade
or profession, and his organizations outnum-
ber those of any other vocation.

With the commercial introduction of the
electric light and the transmission of power
by electricity, the high-speed elevator and
the increase in steam pressures, came also
an increase in the responsibility resting on
the engineer, and in no calling has this
increase been so ra])id or so adequately met.

The Centennial standard for a boiler
horsepower typifies the conditions. Thirty
jiounds of water per hour into steam at
seventy pounds ])ressure was the average
engine consum])tion and average pressure
for that time.

Engines and steam pressures of then are
the exception now, and the big plant with
its big engine of that day is among the small
ones. The man has grown too, and many
a one may be foimd who used to nni a little
slide-valve engine and do his own firing,
but now manages a great i)lant nnd draws
a congressman's salary.

He earns it.

The public neither knows nor appreciates
these things, but the engineer can start a
little thought in the right direction by looking
the part he plavs in modern industrial ]iro-
d net ion.

578

POWER

October 17, 1911

Power Plant of Curtis Publishing Co.

The Curtis Publishing Company, pub-
lisher of the Saturday Evening Post,
the Ladies Home Journal and other well
known periodicals, has about completed
its new 10-story building, facing Inde-
pendence square at Sixth and Samson
streets, Philadelphia.

Although still receiving some of the
finishing touches, the building has been
occupied for several months with the
presses running night and day. To fur-
nish power for these and for lighting
the building a very complete plant has
been installed.

To afford sufficient space at the street
level for the shipping department and
for a courtyard at the rear of the build-
ing, the double-deck type of power plant
was adopted with the boilers situated
over the engines. As a precaution
against the engine vibrations being trans-
mitted to the building, the engines are
carried on a concrete slab which is en-
tirely independent of the steelwork of
the building. This slab is carried on I-

By A. D. Blake

.4 2 2 ^o-kihnvatl phnit
It sing exhaust steam for
lieatiiig. Remote control is
employed for the electrical
apparatus, and meters are
installed on all service lines,
feed-7t'ater lines and circtiits
to all departments; thus per-
mit! iiig accurate operating
records to be kept.

direct connected to Westinghouse direct-
current generators. Their sizes are as
follows: one 18x30x32-inch cross-com-
pound engine driving a 500-kilowatt gen-
erator; three 16x26x32-inch cross-com-
pound engines each driving a 400-kilo-
watt generator; two 12x20x30-inch cross-
compound engines driving 200-kilowatt

the features of the boiler room is its
good ventilation, abundance of light and
ample space around all piping and boil-
ers.

Coal is delivered from wagons to a
conveyer which elevates and distributes
it to a 1200-ton reinforced-concrete bin
located above the boilers. This has a
hopper in iront of each boiler, which
empties into one of two traveling chutes;
these are designed to weigh and hold
1000 pounds of coal each, and discharge
onto the floor in front of the boilers.
Hand firing is employed and the ashes are
discharged into hand cars through hoppers
located under the grates. These empty
into a large ash hopper extending out
into the courtyard and the ashes are
carted away by wagons.

The gases from the boilers are carried
away by a 150-foot steel stack lined with
firebrick and carried on special steel sup-
ports. The natural draft is supplemented
by forced balanced draft which is fur-
nished by a Sirocco blower delivering

teams which rest on concrete piers placed
between the footings of the building col-
umns.

Main Units and Boilers

The total present capacity of the plant
is 2250 kilowatts, furnished by seven units
of various sizes, thus permitting such
combinations as will handle the load most
economically. These units all run at 150
revolutions per minute and consist of
Rice & Sargent noncondensing engines

Fig. 1. General View of Engine Room

generators, and one 14x24-inch simple
engine driving a 150-kilowatt generator.
The engine room is designed to permit
the future installation of an additional
1200 kilowatts capacity.

Steam is furnished at 180 pounds and
125 degrees superheat by four 350-horse-
power, and one 297-horsepower Stirling
boilers. These are arranged as shown in
Figs. 2 and 3 and space is provided for a
duplicate set of boilers along the other
side of the boiler room. Notable among

air under the grates. A second source
of mechanical draft which may be used
instead of the blower, if desired, is
McClave steam blowers, fitted to each
ashpit.

Feed water is handled by a Worthing-
ton outside-packed steam pump and by a
motor-driven Deane pump. Ordinarily
only one of these is used, but when the
load increases to the point that one pump
cannot maintain the water in the boil-
ers at a certain level, the other pump is

October 17. 1911

POWER

579

automatically thrown into service. In- the other. The flues are arranged so that
jectors are also provided to supplement the gases may be bypassed around these
the feed pumps. economizers and discharged direct to the

Fic. 2. View of Boiler Roo.m
The pumps take the feed water from a stack. A venturi meter with an

auto-
feed-

Cochrane heater and deliver to two matic recorder is placed in the

Sturtevant economizers, there being three water line.

boilers on one economizer and two on All high-pressure steam piping is of

steel with welded flanges, and is of such
sizes as to employ high steam velocities.
The general arrangement of piping lead-
ing to the engines is shown in Figs. 3 and
4. With the exception of one 8-inch and
one 6-inch main from the boilers, all
the piping and receivers to the engines
are under the engine-room floor.

Heating System

With a volumetric content of 10,000.000
cubic feet and the building exposed on
three sides, the problem of heating be-
comes an important factor. Both an in-
direct and a direct system of heating are
employed, the former calculated to take
care of ordinary conditions and the latter
to supplement this in extremely cold
weather.

The exhaust from the engines passes
to a 36-inch exhaust main which leads
to the roof. Here it discharges into
a series of heating stacks over which
washed air is drawn by electrically op-
erated Sirocco fans and delivered through
a system of ducts to the various rooms.

For the direct heating the Paul vac-
uum system is used. This also takes
steam from the exhaust main and is a
one-pipe system with the air valves on
the radiators attached to a vacuum pump,
the condensation returning in the ordinary
manner. A Johnston thermostatic control

■ -- ^^ -' ^iTv 5^-

Fic. 3. Section through Boiler Room and Engine Room

580

POWER

October 17, 1911

automatically puts the radiators in service
if the room temperature falls below a
certain predetermined point.

For heating the building when the en-
gines are not in service, or when the
load is not heavy enough to furnish
sufficient exhaust steam, a live-steam con-
nection with a reducing valve is provided.

The returns from the heating system

protection. A large storage tank on the
roof is provided for this purpose in ad-
dition to a steam-driven fire pump cap-
able of delivering 750 gallons of water
per minute. These are connected with
sprinklers on every floor and fire nozzles
on the roof. There is also an outside
sprinkler system which can place a cur-
tain of water between the building and

are furnished by two York refrigerating
machines, each consisting of an 8x12-
inch horizontal Corliss engine connected
to two 9x1 2-inch vertical single-acting
compressors. The brine is circulated by
two triplex motor-driven pumps. The
cooling water for the ammonia condenser
is handled by a deep-well pump which
draws its supply from an artesian well

i iji M

drain into a hot-water tank in the base-
ment and from here pass to the feed-
water heater. Two hot-water tanks are
also provided for service supply.

Fire Protection

Although the building is of fireproof
construction throughout, considerable in-
flammable material, such as paper, ben-
zine, oil, etc., is handled within it; hence
every precaution has been taken for fire

any exterior fire. Fire-engine connections
are also provided outside the building.

Services

Service water throughout the building
is supplied by two motor-driven triplex
pumps each capable of delivering 300
gallons of water per minute against a
head of 198 feet.

Ice for the kitchen service and brine
circulation for cooling the drinking water

driven under the building. An auto-
matically operated valve throws city
water into the line should the deep well
fail.

The drinking water, which is taken
from the city mains, is first passed
through a Forbes sterilizer having a capa-
city of 150 gallons per hour; it is then
pumped up to a glass storage tank on
the roof and from here flows by gravity
to the coolers.

October 17, 1911

POWER

581

A very complete vacuum-cleaning sys- the storage tank. Two systems of dis-
tem is installed throughout the entire tribution for cylinder oil are provided,
building. This is handled by two lotary one for use with high-pressure super-
vacuum pumps of the Platt-Rotrex type, heated steam and the other for the low-

Refrigeratinc Machines and Service Pumps

each capable of discharging 256 cubic feet
of air per minute when maintaining a 10-
inch vacuum on the system.

A 650-gallon oil-storage tank is
situated on the boiler-room floor just
back of the boilers. From this the oil
flows by gravity to the engines, thence to

pressure engine cylinders.

Electrical Equipment

The lighting is at 110 volts and the
power for running the presses, pump
motors, elevators, etc., is at 220 volts. To
provide the 110-volt current the usual

each machine are mounted on an in-
dividual panel located close to the ma-
chine. These are all handled through
remote control from a central bench-
board, shown in Fig. 6. The main
switchboard is divided into two groups
of panels, those on the right for power
circuits and those on the left for lighting
circuits; the three central panels are de-
voted to the balancer sets and instru-
ments.

Each machine is supplied with a watt-
meter and there is a similar instrument
on both the positive and negative bus-
bars with an additional instrument to
show the unbalanced load. Also, the cir-
cuits leading to each department are
metered, thus permitting each department
to be charged with its proportionate cost
tor power and light. An ammeter switch
will throw the instrument on either the
positive or negative side and thus indi-
cate any ground, should one occur.

An auxiliary switchboard, fed from
the city service, is connected with
emergency lighting circuits in the boiler
room, engine room and stairways. This
is automatically thrown into ser\'ice by a
no-load release switch should anything
happen to the plant so as to put the
electrical equipment out of service.

In addition to the installation of meters
on all circuits and the venturi meter on
the feed-water line, both indicating and
recording gages are placed on all water
lines, steam lines, etc. Many of these
are located upon the wall of the chief
engineer's office, which overlooks both
the engine room and the pump room.

Main Switchboard and Benchboard

•1 settling tank and Filters located in the
basement, at which point there is addi-
tional storage for 7.V) gallons of filtered
oil. From here it Is pumped hack to

three-wire system Is employed with bal-
ancer sets, the current being generated
at 220 vnlli.

The circuit-breakers and rheostats for

The plant was designed by and con-
structed under the supervision of Frank
C. Roberts & Co.. consulting engineers,
of Philadelphia.

582

POWER

October 17, 1911

Transmitting Capacities of Pulleys

In order to transmit power from one
pulley to another there must be a differ-
ence in the tensions on the tight and
slacl< sides of the belt. This difference
depends upon the nature of the two sur-
faces, the measure of their friction and
the arc of contact. The latter, however,
is generally fixed by conditfons in the
particular installation, such as diameters
of pulleys, distance between centers, etc.

The tests were all made with a single-
ply oak-tanned leather belt, 5 inches wide
by 0.224 inch thick, 1.12 square inches
in cross-section and 33 feet long. The
pulleys were all nominally 24 inches in
diameter by 8-inch face. A constant
belt speed of 2200 'feet per minute or
348 revolutions per minute of the driving

By Prof. W. M. Sawdon

The variation oj the co-
efficient of friction with slip
jar various kinds of pulleys;
the influence of cork in-
serts; and the relative trans-
mitting capacities of the dif-
ferent pulk\\s.

*Kxieipt from paper delivered at the semi-
mii;il meetins; of the National Associaiion of
fittnn Maiuif.ictiirers at Manchester. Vt..
■jiti'iiilnM- •-'7-.'!ii, 1911. The tests were con-
iclfd hy ilii' inirhor in the laboratories .of
lilev I'l'illpgc. Cornell University.

Kind of Pulley

Cast iron

Cast iron with corks projecting 0.04 inch. . .
Cast iron with corks projecting 0.01.5 inch

Wooden

Wooden with corks projecting 0.075 inch.
Wooden with corks projecting 0.03 inch . .

Paper

Paper with corks projecting 0.008" inch . .

Paper with corks projecting (about) 0.01

inch

per cent, li percent
Slip Slip

2.69
2.89
2.47

Comparative
Transmit-
ting
Capacity at
2 per cent.
Slip

100.0
124.5
133 8
114.3
120.4
118.1
252.8
165.3

218.5

Kind of Pulley

Cast iron

Cast iron with corks projecting 0.04 inch. .
Cast iron with corks projecting 0.015 inch.

Wooden

Wooden with corks projecting 0.075 inch . . •
Wooden with corks projecting 0.03 inch . .

Paper

Paper with corks projecting 0.087 inch

Paper with corks projecting (about) 0.015
mch

per cent. IJ per cent. 2 per cent.
Slip Slip Slip

2.36
2.26
2.26
2.78

2.52
2.41
2.37

Comparative
Transmit-
ting
Capacity at
2 per cent.
Slip

2.33
2.49
2.61
2.46
2.44
2.44
3.20
2.84

100

107.0

112.1

105.6

104.8

104.8

137.5

122.0

133.2

mates average practice more nearly than
does any of the single tensions.

These curves show that for slips of
from 1 to 2 per cent, as commonly used
in practice, the plain cast-iron pulley
has the lowest coefficient of friction and
the plain paper pulley the highest. The
values of the plain uoud pulley lie be-
tween these limits. An interesting fea-
ture of the curve of the wood pulleys •
lies in the fact that up to one-half of 1
per cent, slip it follows very closely that
of the paper pulleys, after which the slip
increases rapidly and at 1 per cent, the
coefficient of friction is only approxi-
mately a mean between those of the
cast-iron and the paper pulleys. As the
slip further increases, the curve be-
comes even flatter and beyond 3 per cent,
the coefficient of friction is less than that
for cast iron. This condition explains
in part a commonly accepted objection
to the use of wooden pulleys; that is,
a decidedly small capacity for carrying
an overload.

The introduction of cork inserts into
the faces of the pulleys resulted in each
case in a general change in the char-
acter of their coefficient of friction. The
wooden and cast-iron pulleys tested with
the cork inserts were the same as used
in the plain-pulley tests. The cork area
was from 37 to 39 per cent, of the total
pulley face and two complete sets of
tests were made, one for a aV'-inch pro-
jection of the corks and the other for a
5t-'nch projection.

In the case of the cast-iron pulleys,
each of the cork-insert curves shows a
material increase in the values of the
coefficient of friction at lower slips and
running up to 3 per cent. For the longer
corks the values of the coefficient of fric-
tion between 1 and 6 per cent, slip are
close to those of the plain wood pul-
leys. Below 1 per cent, slip the wooden

pulley was maintained throughout. Ob-
servations were made on belt slips for a
series of different initial tensions, each
covering brake loads from a minimum
of 20 pounds to the maximum that the
belt would carry or that could be safely
put on the driving motor. In each set
of tests six different initial belt tensions
were used, as follows: 37.5, 75, 112.5,
150, 187.5 and 225 pounds per square
inch of cross-section.

The accompanying curves show the
results of the tests with reference to rela-
tive values of the coefficient of friction
and belt slip for all the pulleys tested.
These curves were plotted by taking
values corresponding to initial belt ten-
sions of 150 and 175.5 pounds per square
inch and averaging them. This range of
tensions was chosen because it approxi-

1

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2

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8

Per Cent. 5lip

V.\RiATioN OF Coefficient of Friction with Slip

October 17, 1911

POWER

pulleys have the higher values. With
the shorter corks, considerable advantage
is shown over plain cast-iron pulleys as
well as plain wooden pulleys up to about
4 per cent, slip, after which the coeffi-
cients are but little higher than for the
plain cast-iron pulleys. Either of the
cork-insert cast-iron pulleys, however,
shows a large overload capacity at high
slips.

In the wooden pulleys the cork inserts
slightly increase the transmitting capa-
city for very low slips and up to about
one-half of 1 per cent. Between 'j and
1 >j per cent, slip, the plain wooden pul-
leys have the higher values, while be-
yond 2'i per cent, the cork inserts again
show an advantage.

With the paper pulleys, however, the
cork inserts proved detrimental to the
transmitting capacity for practically the
entire range of slip, this being more
marked in the longer cork projections.

A simple method of comparison is that
afforded by Table 1, which shows the
relative transmitting capacity of different
pulleys at various practical slips.

These values hold for a belt speed of
2200 feet per minute and an initial ten-
sion of approximately 170 pounds per
square inch of belt cross-section. The
transmitting capacity of the cast-iron pul-
ley was taken as representing 100 per
cent.

While these values represent exactly
the power transmitted by the different
pulleys in the tests, a comparison on this
basis is not fair in that it does not take
into consideration the variations in the
arc of contact of the belt on the different
pulleys, nor the greater stress occasioned
in the tight side of the belt by the pul-
leys carrying the higher loads. One of
the observations of the tests was that
with increasing loads, the arc of contact
on the pulleys also increased. For some
pulleys this was more marked than for
others. Furthermore, it is an accepted
fact that the higher the working stress
in the belt, the shorter is its life. A fair
comparison then should be based on both
these factors remaining constant. This
is a difficult comparison to make directly
from the tests. It can. however, be made
with a large degree of fairness by usinc
one of the formulas commonly used fnr
belt drives. Table 2 was therefore pre-
pared giving relative transmitting capa-
cities of the various pulleys at different
slips, when based on constant arcs of
contact and constant belt tensions.

These values do not represent actual
*" nervations from the tests but were cal-

.ited by means of Naglc's formula.

ng an arc of contact of 180 degrees

I a maximum belt tension of 250

inds per square inch of cross-section

1 the values of the coefficient of fric-

■1 from the results of the tests as given

!he set of curves.

Recent Explo.sions in England

Among the recent British Board of
Trade reports on explosions are the fol-
lowing:

Cast-iron Blowoff Pipe
At the Londonderry collieries, New Sea-
ham, a cast-iron elbow piece fitted in

Fig. 1. Elbow Piecc in Blowoff Fails

the blowoff pipe failed. The pipe was 22
inches long horizontally and 9 '4 inches
vertically, with a rib 1 inch thick and 2
inches deep extending from the upper
flange to within 6 inches of the smaller
flange. As will be seen in Fig. 1, the
fracture of the elbow pipe occurred be-
tween the bottom of the boiler and the
blowoff valve.

As the waste pipe immediately beneath
the boiler was unsupported for a length
of 23 feet, there was considerable bend-
ing moment upon the elbow when the
blowoff valve was opened; therefore the
pipe was so weakened that it could not
withstand the strain.

On the day of the explosion the fire-
man of the boiler, noticing that the
water level was above the top of the gage
glass, went below to blow off. When he

Fmlhrh Oh Stop Valve

opened the valve the explosion occurred
and he was severely scalded.

The boiler was emptied in about 15
minutes and on examination it was found
that the pipe had been carried away.
Steel pipes will replace the cast-iron el-
bows and the waste pipe has been more
securely blocked.

Stea.m Stop-valve Chest

The explosion of a steam stop-valve
chest, which occurred in the works of
Richardson, Westgarth & Co., Middles-
borough, was due to the inefficiency of the
valve chest and to the condition of the
cast iron caused by the difference in
temperature above and below the valve,
the chest being of such unequal thickness
that it fractured when the valve was
opened.

The chest (see Fig. 2) was fitted with
a brass spindle, a 4-inch valve, and the
inlet and outlet branches on the chest
were of 4-inch bore. To the flanges. 9
inches in diameter and 1 inch thick, the
steam pipes were secured by eight frj-
inch bolts; the cover was secured by the
same number of '»-inch bolts; the chest
was S'l inches internal diameter and
varied from "s to ,'.:■ inch in thickness.
The valve was occasionally reground, but
no other repairs had been required.

A hydraulic test of 250 pounds per
square inch was given the valve chest
before it was delivered by the makers;
they did not appear to know that it was

Fic. 3. Water Hammer Caused This
Rupture

required for a working pressure of 200
pounds.

When the fireman on the boiler re-
ported that he had I7,S pounds pressure,
he was ordered to connect up, as the
pressure on the steam gages on the main
boilers corresponded. The fireman went
on top of the boiler and had just eased
up on the valve when the explosion oc-
curred.

No evidence of water hammer was
found after the explosion, but the in-
clined position of the pipe, the globular
form of the valve chest and the posi-
tion of the drain were all favorable to
the accumulation of water. It is be-
lieved that the slightest internal blow
on a chest of such unequal thickness
would be sufficient to cause fracture.

A short length of copper steam pipe
has been fitted in place of the exploded
chest and the intermediate stop valve has
been omitted.

Stop-valve Chest

This explosion, in a print works near
Clossop. was caused by the failure of a

584

POWER

October 17, 1911

stop-valve chest, due to water hammer,
no drain being fitted to the chest to re-
lieve it from water of condensation when
it was closed.

The valve was of the mushroom-coned
type having a central spindle beneath, its
seat and branches being of 4-inch bore.
The spindle was Ijx inches in diam-
eter in the gland with a square-threaded
I's-inch screw, four threads to the inch,

working in a nut in the boss of the chest
cover. The globe-valve chest (Fig. 3)
was made of cast iron, the valve, seat,
gland and spindle being of brass, with
5-inch internal diameter at the top. From
flange to flange the chest was 12' j inches,
the flanges being 9 inches in diameter,
'' :i inch thick, and secured to the steam
pipes by four S/^-inch bolts; the maximum
pressure was 50 pounds per square inch.

When the works were closing for the
day the attendant noticed a steam-pipe
joint leaking at a valve near the bend.
He shut down the stop valve instead of
closing the steam-supply valve and went
home. He did not mention what he had
done, but the next morning tried to
tighten up the leaky joint and in attempt-
ing to reopen the stop valve, caused the
explosion almost immediately.

Purchasing Coal under Specifications

A very interesting and instructive dis-
cussion upon "The Purchase of Bitumi-
nous Coal under B.t.u. Specifications,"
by F. P. Crecelius, is contained in the
annual report of the committee on power
generation of the American Electric Rail-
way Engineering Association.

After reviewing the various publica-
tions upon this subject as gotten out by
the Bureau of Mines, Mr. Crecelius sum-
marizes the advantages of purchasing
coal under definite specifications as found
by the Government. These are:

1. Bidders are placed on a strictly
competitive basis as regards quality as
well as price.

2. The field for both purchaser and
dealer is broadened, as trade names can
be ignored and comparatively unknown
coals offered by responsible bidders may
be accepted without detriment to the pur-
chaser.

3. The purchaser is insured against
the delivery of poor and dirty coal, and is
saved from disputes arising from con-
demnation based on the usual visual in-
spection.

4. Experience shows that it is not al-
ways expedient to reject poor coal, be-
cause of the difficulty, delay and cost of
removal. Under definite specifications,
rejectable coal may be accepted at a
greatly reduced price.

5. A definite basis for the cancelation
of the contract is provided.

6. The constant inspection and an-
alysis of the coal delivered furnish a
check on the practical results obtained in
burning the coal.

The Government cautions further that
the aim in purchasing coal for any power
plant should be to obtain a fuel which
will produce a horsepower for the least
cost, "all" things being considered. The
most careful attention should first be
given to the nature of the existing fur-
nace equipment, draft and load; the
character of coal best suited to the plant
conditions, the number of heat units ob-
tainable for a unit price; the cost of
handling the coal and ash; and the pos-
sibility of burning the coal without smoke
or other objectionable features.

The usual and customary element upon
which premiums and penalties are based
is the heat content expressed in British
thermal units. The justification for this
is based upon the fact that coal which

B}' purchasing coal un-
der definite specifications
the Bureau of Alines claims
that bidders are put on a
strictly competitive basis;
the purchaser is insured
against poor quality; re-
jectable coal may be ac-
cepted at reduced prices,
and there is a check on the
practical results obtained.

gives up the most heat per pound is
the most valuable. And if it were not
that other elements, such as ash, sulphur,
volatile matter and moisture are pres-
ent in varying amounts in different grades
of coal, requiring altogether different fur-
nace equipment to burn economically,
the matter of drawing up specifications
would be comparatively simple.

However, because of the presence of
the other disturbing elements mentioned,
and because of the further fact that in
any market a number of grades of coal
can be had at different prices, which vari-
ation in price is usually all out of pro-
portion to the respective steam-making
quality of the various coals offered, it
follows that other restrictions must be
added to the specifications.

The most disturbing elements in coal
are ash, sulphur and moisture.

The presence of an excessive amount
of ash in any coal manifests itself in the
nature of a reduction of capacity because
of its occupying a relatively large amount
of effective grate area with inert matter.
It is also the source of additional ex-
pense as regards cost of removal and
extra wear and tear on ash-handling ap-
paratus. It should therefore be restricted
to a certain limited amount, no premium
being allowed for a minimum. Penalties
for amounts in excess of the allowable
limits should be provided, and these pre-
ferably should become excessive after a
certain value.

Sulphur, either free or in combination
with other elements, in excess of 3.5 per
cent, is decidedly disadvantageous, es-

pecially when burned in certain types of
furnaces. It is the principal source of
formation of fusible clinkers, which clog
the fire, adhere to the grate bars and In-
crease enormously the cost of maintain-
ing the furnaces. No premiums for a
minimum should be provided.

Moisture is a matter entirely beyond
the control of the dealer, depending upon
weather conditions, distance of transpor-
tation, etc., and if the heat determination
is made upon samples either "dry" or "as
received," it has been compensated for.

If coal bills are settled according to
weights at the receiving station this value
should be determined and the B.t.u. de-
termination made upon samples "as re-
ceived." If bills are paid according to
railroad weights at the loading station the
B.t.u. determination should preferably be
made on a dry sample.

Volatile matter, more than any other
element, provides the means for deter-
mining the source of the fuel supply. The
amount of volatile matter in coal in-
creases with the distance from the At-
lantic coast to the Mississippi river and
furnishes an indication of the section in
which the coal was mined. The presence
of volatile matter is not necessarily detri-
mental to the coal; however, because of
existing furnace equipment and severe
smoke regulations, it may be necessary
to restrict a fuel containing excessive
amounts of volatile matter.

In some cases the premiums and penal-
ties provided in coal specifications can-
not be proportional with respect to the
B.t.u. values, but must be of an accelerat-
ing nature, either above or below stand-
ard. This is the case in the specifications
of the Cleveland Railway Company, and
a short outline of the underlying condi-
tions responsible for this is as follows:

There are available in the Cleveland
market three grades of slack coal, at dif-
ferent prices, and of different steam-mak-
ing qualities. These, for present pur-
poses, may be designated as grade I.
grade 2 and grade 3. The market prices
are according to quality and depend also
upon the freight rates, but in no case is
the market price anywhere nearly pro-
portional to the relative value of the dif-
ferent grades when based upon evapora-
tion.

After a thorough study of the relative
value of these coals, results obtained after

October 17. 1911

P O W E R

585

careful and prolonged tests indicated that
grade 2 coal was the best suited. On ac-
count of a loss in effective plant capacity
when burning grade 3, due to its poorer
qualities, this fuel had to be cut out of
consideration. Grade 1 coal is very sat-
isfactory and is received, but payment
is made according to its value as com-
pared to grade 2 coal, which has been
made the standard in the contract.

The value of the relative fuels, the
prevailing market price and settling price
are shown in the following table:

Kind of Coal <jraij.' 1 i;ra(l>-i' <;rade.3

B t.u 13,3JO 12,700 12,130

Vsh 11. 60^1, l.'S.SO':; 18.11%

Sulphur 2.03% 3..i0<.; a.lo%

Moisture 1 . 52% 2 . TO'Jo 3 . .55%

\'olatile combust-
ible matter ... 31.33% 35.62% .35.03%

Fi.xed carbon .53.52% 44.38% SS.ier;

, , .Market price per

ton deUvered. . .$1 7.5 SI 60 .?1 in
Settling price ac-
cording to con-
tract $1 r.7 SI 111) SI :iL>

Statements and conclusions relative to
the unfairness of arbitrary penalties and
premiums, which are not based upon real
or proportional variations, abound, and
lately considerable stress has been laid
upon the supposedly excellent results to
be obtained from a combination method
of purchase based upon an evaporation
basis and an analysis basis. It does not
seem proper to make an outside party
responsible for the economical perform-
ance of equipment not in his control, sim-
ply because he happens to supply a nec-
essary commodity. This is the circum-
stance when the coal dealer is called upon
to supply fuel on a basis of evaporation
and this disadvantageous practice will
continue to the mutual dissatisfaction of
both parties so long as doubt and uncer-
tainty shroud the matter of a proper basis
of fuel purchase.

The report contains tn detail the coal
specifications of the Cleveland Railway
Company and those of the New York In-
terborough Rapid Transit Company. In
the specifications of the former company
the standard for heat value per pound of
dry coal is 12,610 to 12,759 B.t.u., in-
clusive. The premiums range upon a
graded scale as high as 21 cents per ton
above standard price for heat values of
13,960 B.t.u. and above; whereas the
penalties range as high as 50 cents per
ton for heat values of 10,660 to 10,809.

The standard for ash is placed at from
0 to 15 per cent., with no premium for a
minimum amount. For excess ash, how-
ever, the penally reaches 50 cents per
ton for 29.1 per cent, and over. Likewise
a heavy penalty Is provided for sulphur.
The standard is placed at from 0 to 3.5
per cent, and the penalty increases
gradually until it is 45 cents per ton, cor-
responding to ash of 10 per cent, and
over.

It is further stipulated that if the con-
tractor should fail at any time to supply
coal of such quality or quantity as stipu-
lated in the contract, the railway com-
pany shall have the right to purchase coal
in such quantities as may be needed, at

the market rates and fn the open mar-
ket, and collect the additional cost, if
there be any, from the contractor. Also,
the railway company shall have the right
to cancel the contract and relet the work
should the contractor fail to fulfil all
the terms of the contract.

The specifications of the Interborough
Rapid Transit Company provide for the
acceptance, without penalty, of coal con-
taining 20 per cent, or less volatile mat-
ter, 9 per cent, or less ash and 1.5 per
cent, or less sulphur. This is designated
as the standard with no premiums for
minimum amounts, but with penalties
ranging as high as 18 cents a ton for 24
per cent, or more volatile matter, 23 cents
per ton for 13.5 per cent, or more ash
and 12 cents per ton for sulphur up to
2.5 per cent. The premiums for an ex-
cess in B.t.u. over the standard of 14,201
to 14,250 run as high as 26 cents per ton
for 15,505 B.t.u. per pound of dry coal
and the maximum penalty is 45 cents per
ton for a heat value of 12,000 B.t.u. or
!ess per pound of dry coal. The average
premium and penalty is about 1 cent per
ton for each 50 B.t.u. in excess or short
of the standard.

New I'se for Deep Well

Pump

Bv W. T. Griffith

The Big Sandy river is a stream which

varies from about 2 feet of water to 35

feet at extreme high water; and during

is situated some distance from the river,
and to carry a steam pipe that distance
was not thought practicable.

The writer conceived the idea of set-
ting a deep-well pump on top of thi.
river bank, at such an angle as to run
the drop pipe parallel with the sloping
bank of the river and place the working
barrel at low water. This would avoid
any trouble of priming the pump and at
the same time the motor and working
head could easily be got at and at all
times be out of the way of flood waters.

When this proposition was presented
to the difterent pump manufacturers,
none of them could show any good rea-
son why it would not work, but all with
one exception seemed to be afraid of it.
The worst objection presented is that
the sag of the rods against the drop pipe
would wear them out. The rods are
made of wood and the pipe of iron. The
wear is not great and, even if the rods
do wear out, the drop pipe is easily ac-
cessible and it can be uncoupled and a
new rod put in. This wear only comes
on the downstroke, as on the upstroke
the rods are taut.

The pump installed is a Piatt Iron
Works, designed for a working head of
151 feet, with a stroke of 24 inches and
a 6'4-ineh working barrel. The pump
makes 30 strokes per minute. The set-
ting of the working head at an angle ne-
cessitated some changes from the regu-
lar pattern in order to connect the 15-
horsepower motor.

To avoid some rock excavation the
working barrel was placed above ex-
treme low water but below the average

Low Water Line
ARR\Nr,l:MKNT OF PuMP AND SUCTION LiNE Strainer

the heavy rains of spring and fall the
rises often come suddenly. During
high water the river carries large quan-
tities of mud and sand, which as the
river falls is deposited along the banks
and on the bars.

Heretofore the general way of obtain-
ing water for power plants and railroad
water tanks has been by means of a
steam pump mounted on a truck which
can be raised and lowered on a track laid
up and down the banks, the main dis-
charge line having several openings pro-
vided for attaching the discharge of the
pump. Moving the pump and changing
the pipe connections require consider-
able lime.

The power plant of the Colonial Coal
and Coke Company, at Prcsfonsburg. Ky.,

stage, and from the working barrel a
suction pipe is carried out into the river
and at the end is placed a 100-mesh
screen Should the river deposit silt
around the suction or other obstructions
gather around the screen, there is pro-
vided a 2-inch bypass from the main dis-
charge to the suction, which on being
opened will force anything away from
the screen.

The pump discharges into a 20,000-
gallon tank placed on the hillside 145
feet above the level of the check valve
of the pump. When the pump was first
started considerable trouble was caused
by fluctuations in pressure. This has
been practically overcome by increasing
the size of the air chamber, which is
now 12 inches by 7 feet.

586

POWER

October 17. 1911

Power Derivable from Ocean Waves

Dynamic theories of water waves have
been the subject of inquiry by many
eminent engineers and scientists. The
results of their researches tend to show
that the energy created by ocean waves,
whether derived from the action of tides,
winds or other forces in nature, is event-
ually expended in lifting, tossing and
driving the water in innumerable forms
of motion. During periods of extraor-
dinary disturbanees, the water's surface
and subsurface energies are extremely
complex. In many places these disturb-
ances are augmented by combinations of
local conditions and neither the surface
nor subsurface waters hold to a uniform
degree of activity for any considerable
length of time. These features are true
of localities where during times of or-
dinary ocean storms the impulses of
waves have been known to exceed 3000
pounds to the square foot; but such
places would be entirely unsuitable for
the location of wave motors, because of
the great difficulty in securing stability
of mechanism and regularity of the
propelling power.

Modern methods have made possible
the storage and long-distance transmis-
sion of power developed from irregular
sources; hence the problem of obtaining
power from ocean waves is an encourag-
ing one. But in view of the inconstancy
of the energy, the doubtful efficiency and
hazard attending the construction of
plants designed for utilizing energies of
the deep sea, it is fair to ask that prac-
ticability of wave motors should first be
demonstrated in shallower waters, where
all elements are under greater control.
Although subsurface activities are usual-
ly concomitant with surface activities,
one may exist without pronounced de-
velopment of the other. Water in an or-
dinary tank may have its surface dis-
turbed into the formation of waves without
creating a perceptible subsurface disturb-
ance beyond the body of the surface wave
form itself; or, on the other hand, the
whole body of water in the tank may be
agitated and may be brought to rest
again, without a perceptible formation of
surface waves. In the latter case the
particles act and counteract on each other
and on the sides of the containing ves-
sels, assuming swirls and eddies or set-
ting up a churning action which is ac-
companied by surface froth and foam.

When subsurface energies resolve
themselves into surface forms, it is the
result of unbalanced kinetic energies
recovering their equilibrium by overcom-
ing the force of gravity in lifting some
of the water and thus storing potential
energy in the wave form above the gen-
eral level. When conditions are favor-
able to this manner of forming the sur-
face w'ave, its propagation continues in
the same manner until complete equilib-

By Franklin Van Winkle

A disciission of the wave
forms in shallow and deep
waters a)id the limitations
met with in attempting to
convert the energy of the
waves into useful work.

rium is established by one-half of the
original subsurface kinetic energy being
converted into potential energy. But
when conditions are not thus favorable
for the transformation of one-half of the
kinetic into potential energy, the subsur-
face forces, in seeking equilibrium with-
out having parted with any of their
original intensities, when opposed, as by
coming in contact with stationary objects,
naturally assert themselves with double
the violence. Hence, havoc is frequently
wrought by the pounding and boring
action of the sea at times when surface
waves are insignificant. Many people
have the mistaken idea that surface and

Fig. 1. App.\rent Rolling Effect

subsurface energies are in direct propor-
tion to the hight of the surface form of
the wave.

Before passing to a consideration of
the energy of the ordinary forms of
waves a few further observations may
not be amiss respecting subsurface en-
ergy. Until subsurface disturbances
have worked themselves into some uni-
formity of wave form, the kinetic forces
are exceedingly complex and confused.
When the kinetic energy is in the form
of a steady stream, as in the instance of
a tidal current flowing through a narrow-
channel, then the energy of practically
the whole body of water continues as
kinetic energy, and the problem of obtain-
ing power becomes identical with condi-
tions that are met by the installation of
current waterwheels. This is not only
one of the oldest methods of obtaining
power from water, but also one of the
most expensive, in proportion to the
amount of power obtained.

In view of the energy with which waves
are hurled against cliffs and masses of
masonry, it might seem probable that an
area placed normal to the general wave

action would present favorable oppor-
tunities for the development of power.
The fact remains, however, that whea
kinetic activities of the w-ater are thus
expended they are extremely irregular.
In localities where wave action of this
kind is continuous, the task of installing
a plant for intercepting the energy of
the water would be very hazardous and
of doubtful permanency. But assuming
that the difficulties of construction and
maintenance are overcome, the kinetic ac-
tion has to be received and absorbed in
the form of irregular impulses varying
from violent, impacts to negative hydro-
static pressures due to the "suction-like"
action of receding volumes of water.

The simplest forms of ocean waves
are those which are propagated in deep
water and they are referred to in this
connection mainly because the funda-
mental theories of the simple wave mo-
tions are based upon deep-water condi-
tions. It may be said in passing, how-
ever, that the leading characteristics of
shallow-water waves, which are most
likely to be considered for imparting en-
ergy to wave motors, are analogous to
those of deep-sea waves.

Extensive and critical observations of
ocean waves made by officers of the
French and English navies and by inde-
pendent ^.experimenters on wave motions
produced in large glass tanks, appear to
confirm the leading principles of wave
motions that are deducible from what is
termed "the trochoidal-wave theory."
This theory is based upon the motions
which are set up in deep-sea waves or-
dinarily known as "rollers" when such
waves are propagated uniformly and in
a regular and uniform series. When a
simple deep-water wave passes over a
point, each surface particle and the
particles of all the water to a consider-
able depth describe circular or elliptical
orbits in vertical planes which are perpen-
dicular to the ridge of the wave. Under
normal conditions it is assumed that the
particles describe orbits which are true
circles; that they travel in their circular
orbits at uniform rates of speed once
during the passage of a complete wave
form measured from the center of a crest
to the center of a succeeding crest; and
that the profile of the wave surface takes
the form of a trochoid.

The term "roller," commonly used with
reference to wave motions, is undoubtedly
derived from a popular but erroneous
notion that wave motions consist of pro-
gressive rolling over and over of a body
of water in the form of a cylinder or
roller partly submerged below the gen-
eral surface, as indicated in Fig. 1. There
is some excuse for this opinion; for the
crest of the wave and its rounded form
of breast and back down to about half
of the total depth of the wave, partake

October 17, 1911

POWER

587

of motion in the direction of travel of
the wave form, resembling the upper part
of a rolling cylinder. From a geometrical
analysis of the motions of the particles
it will be seen that in the ordinary, fully
developed deep-water wave, the "rolling-
cylinder" idea is not confirmed but that
the particles move in orbits whose cen-
ters are fi.xed, except for a lateral mo-
tion which they may assume along with
shifting of the whole body of the water,
which is very small in comparison with
the speed at which the form of the wave
travels over the surface of the water.

Oirection of Travel of Wave for.

Fic. 2. Successive. Positions of Float

Special attention is called to the fallacy
of the "rolling-cylinder" idea to guard
the reader against receiving any such
impression from hasty perusal of the dia-
grams of wave motions. The orbits of
individual particles, drawn as complete
circles or ellipses, are often wrongly con-
strued as illustrating solid cylindrical
bodies of water.

Actual Motion of Particles

Assuming that the actual motions of
a small group of surface particles of
the wave are the same as that of a small
float carried on the wave, a study can
then be made of the motions of the sur-
face particles from observations of the
motions of the float. By photographing the
float, from a stationary position, allowing
the exposure sufficient time to get the
complete passage of a wave, if the float
affords good reflection of light in strong
contrast with light received from the sur-
face of the water, a view may be had of
the path of the float in a single exposure.
If there were no general forward motion
of the whole body of water, an exposure
continued during the period of two or
more wave lengths would show the path
in the form of a continuous curve, re-
peating once for each wave length. But
the form of curve and the velocity with
which the float passes over different
parts of its path could be best ascer-

tained by taking a series of instantaneous
photographs at equal intervals of time.
Such a series of photographs of con-
secutive positions of the float, and corre-
sponding positions of the wave, would
resemble the series shown in Fig. 2, in
which a small float is represented in the
successive positions at P, P,, P;, Pj, etc.,
finally assuming the position P., identical
with the original shown at P. One would
expect that if the wave crest had a uni-
form advance in the direction of the ar-
row V, the form of wave in each case
would be the same, excepting that the
crest would be uniformly advanced as at
Pi in the successive cases, until the wave
crest has passed over a full wave length
as at P, in the last case. If a series of
views such as shown in Fig. 2 are super-
imposed, one over the other, in such man-
ner that views of stationary objects, like
the piles S and Si register over each
other, then successive positions of the
wave's crest and corresponding positions

finally falling at At and, continuing, will
follow in the curved path A,R.R,R.R„
By finding successive positions occupied
by the point R for a large number of
points of tangency, such as /!,, A^, A;., the
continuous path is determined which
would be described by the point R when
the circle A R \% rolled along the line A B.
The curve thus described by a point in
the circumference of a circle rolled along
a straight line is called a "cycloid."

By extending the radius C R to a
point 7" outside the rolling circle, suc-
cessive positions of the point 7" can be
determined, as it describes the path indi-
cated by the dotted line for successive
positions of the center of the rolling cir-
cle. This curve is called a "curtate
cycloid." In the same manner one may
determine the successive positions of a
point P which is within the circumfer-
ence of the rolling circle. This cur\'e
r*! P. P.. . .P. is called a "prolate cycloid."
The term "trochoid" is used to denote

FoR.MS OF Wave Superimposed upon One Another

of the float would be brought together
as shown at 1, 2, 3, etc., in Fig. 3, and
lines connecting adjacent points will show
the path described by the float during one
full wave length.

Referring to Fig. 4, A B represents a
straight line and A R is a circle tangent
to A B at A. If the circle A R is rolled
along the line A B in the direction indicated
by the arrow W, and the distance from A
to B is equal to the circumference of the
rolling circle A R, then in half a revolu-
tion a point R at the extremity of the

<-. Length of Trochoidal

i T+

both the curtate cycloid and the prolate
cycloid, although the "trochoidal-wave
theory" almost exclusively deals with
properties of the prolate cycloid.

The Trochoidal Motion

As previously stated, the trochoidal-
wave theory is based on the assumption
that the profile of the surface wave is
in the form of a trochoid. It can be
shown, as assumed by this theory, that
dynamic equilibrium is satisfied in this
form of wave when the moving particles
Wavt .3H

Fig. 4. Development of the Cycloid and Trochoid

diameter A R will fall on -4 8 at ^. mid-
way between A and B; in a complete
revolution the point A of the circle A R
will again touch the line /) B at the point
H and the point R would fall vertically
under B. If the original semi-circle
/1-1-2-3-/? be divided into four equal
parts, /1-I, .1-2, 2-3 and 3-W, and A A, be
divided equally into the same number of
spaces, then point 1 will fall on A, and
when il does, the center of the circle will
be at C, in the vertical line A, C. and will
be similarly rotated for succeeding points
of tangency A,. A^. etc. The point R will
be carried to the positions R,, R:, etc.,

of water describe orbits which arc cir-
cles whose centers are fixed with refer-
ence to the uniform movement of the
wave form, and that each particle, travel-
ing at uniform speed in its orbit, makes
a complete revolution once during the
passage of each complete wave.

It has been observed that these condi-
tions are usually characteristic of natural
deep-water waves, but the same general
relations of wave form and motions of
particles have been found to exist in
artificially formed waves.

A deep-sea wave of this form may be
assumed to travel over the general sur-

588

POWER

October 17, 1911

face at a uniform rate of speed within
its own length, although, taken as a series,
oncoming waves may increase in length
or hight from the action of the wind or
may die down into a calm. The same
trochoidal conditions exist, though the
properties may be different and there is
reason for the belief that not only do
waves take on other forms as a result
of initial disturbances, but upon running
out into deep water they quickly work
down into the trochoidal form.

According to the trochoidal theory, if
the wave form, shown by the successive
positions in Fig. 2, is an ordinary deep-
water wave, then the curvature of the
profiles in each case will be that of a
prolate cycloid; and if the path of a
particle such as P has been correctly de-
termined, as shown by points 0-1-2-3-4-
5-6-7 in Fig. 3, then these points will be
found to lie on the circumference of a
perfect circle; and having been observed
at equal intervals of time they will be
equally spaced around such an orbit
circle.

It is of interest to trace the geometrical
relations between the wave form and the
oibital motion of a particle, showing their
conformity to the theory. These relations
may be understood by reference to Figs.
2, 3, and 4. In position a. Fig. 2, P, P
represents the profile of a half wave
length from the center of the crest to the
center of the trough of the wave, the
curvature of profile being drawn in the
same length, hight and form of trochoid
as the semi-trochoid P P, P, P= P> in
Fig. 4.

Assuming that the horizontal direction
of travel of the wave form is in the direc-
tion of the arrow V in Figs. 2 and 4, the
crest for half the whole depth of the
wave travels forward with the wave mo-
tion, while the surface of the trough, up

DirecTicn of Form of Wave

P4

Fig. 5. Orbit Circles Diminmshing v(ith
Increased Depth

to about one-half the depth, travels back-
ward, as indicated by the small arrows.
As the surface form goes forward, a
surface float dropped in the trough as at
P is lifted, but moved backward until it
reaches half the hight of the wave, as at
P:; next it is caught by the forward mo-
tion of the breast of the wave and carried
forward and upward to the very top as
P.; then descending on the back of the
wave, continues in a forward motion to
P-. and to P,. In falling with the trough
of the wave from the latter position it

moves backward with the trough through
position P- and then resumes position P
ready to repeat the cycle.

In Fig. 2 the successive positions
are of the same trochoidal form as
P P, P= Ps P, Ps P.. P: P> in Fig. 4, but each
with the crest of the wave advanced one-
eighth of a wave length. The relations
which the circular orbit bears to the
trochoidal form will be better understood
from a reexamination of the construction
of the trochoidal form. Fig. 4. Refer-
ring to Fig. 4, the trochoidal form P. to
P, was understood to be the curved path
that would be traced by the point P being
carried along with the rolling circle A R
in rolling along the line A B from A to
Ai. Assuming C P to be the radius of
the orbital circle of a surface particle,
the distance A Ai being equal to one-
eighth of the circumference of the rolling
circle and equal to the arc A-\, the point
1 falls at Ax so that when the center of
the rolling circle comes into the same
vertical line as /I,, the radius CP has
advanced to C Pi. It is apparent, there-
fore, that if the center of the rolling

Fig. 6. Circular Orbits Changing to

Elliptical Form in Shallow Water

circle and orbital circle were stationary,
a revolution of one-eighth of a circumfer-
ence would carry the point P up and
around on the orbit circle which would
be in the line Pi / at the same elevation
as P,. As C 7 is parallel to C, P, the dis-
tance from Pi to ] equals the distance
from Ci to C and this is equal to one-
eighth the total wave length A B. Hence,
with the center of the orbital circle fixed,
a horizontal movement of the trochoidal
form toward P in direction of the arrow
V through a distance PJ would be coin-
cident with the movement of the particle
through one-eighth of its circular orbit.
After being raised as high as the center
of its orbit, as shown at P-, then in rising
to a higher position as P-, the particle
has a horizontal motion in the same di-
rection as the wave, until it has again
fallen to half the hight of its orbit circle,
as at P, and then falls again with the
backward motion of the trough of the
wave, as previously described.

To satisfy the trochoidal equilibrium
of the surface, the body of water under
the surface divides into an indefinite
number of trochoidal subsurfaces, each
of which must have been originally com-
posed of horizontal surfaces which, by
passage of the trochoidal wave, are con-
verted into trochoidal subsurfaces. Thus,
in Fig. 5 the trochoidal surface form be-
ing P, Pt P,, the original horizontal sub-
surface layers fci b, b,, c, c. c, di d, ds, etc.,
become trochoidal surfaces, the orbit
circles of each diminishing in diameter

in geometrical progression as the depth
increases in arithmetical progression.
Particles at the greater depths follow the
same law as the surface particles. The
subsurface trochoidal surfaces are con-
sidered as generated simultaneously with
the same angular displacement in all
circular orbits whose centers are in the

Fig. 7. Elliptical Orbits Distorted on
Sloping Beach

same vertical; and, as in the case of
orbits of surface particles, the centers of
the subsurface orbits lie a little above
the position that the particle occupies
before it has been disturbed.

Circular orbits, thus established, con-
tinue, so long as the depth of water ex-
ceeds about one-half the length of the
wave; but as the wave comes into shal-
lower water, the whole system of cir-
cular orbits become elliptical, with the
longer axes horizontal, as indicated in
Fig. 6. Vertical motion decreases more
rapidly than horizontal motion at the
greater depths; hence the deeper a par-
ticle is situated, the more flattened is its
orbit, so that a particle in contact with
the bottom simply moves forward and
backward, without any vertical motion, as
shown at C — C, C — C, etc., in Fig. 6.

The trochoidal curves thus developed
by elliptical orbits tend to make the crest
of the wave sharper. When the orbits
are thus converted from a circular to an
elliptical form, the tirhe occupied by each
particle in making one revolution in its
flattened orbit is the same as it required
in traversing its orbit in a circular form.
Hence, when a series of waves advance
into water gradually becoming shallower,
their periods remain unchanged, but their
speed and consequently the lengths of
the waves diminish and their slopes be-
come steeper. The elliptical orbits be-
come more and more distorted, so that
the breast of each wave gradually be-
comes steeper than its back and the ad-
vancing change of form continues as if
the crest of each wave was overtaking
the trough in front of it. This is indi-
cated by the approach of A toward B, and
B toward C in Fig. 7, until finally the
front wave curls over beyond the ver-
tical, its crest falls forward on the beach
and breaks into surf.

The ordinary deep-sea wave, from its
formation to the time it is broken up into
surf, may be said to have passed through
three distinct stages:

( 1 ) The trochoidal form with circular
orbits of its particles, while in water of
greater depth than one-half the wave
length.

(2) The trochoidal form with el-
liptical orbits of its particles, while in
shallower water with reduced length,
hight and speed of wave.

October 17, 1911

POWER

(3) The shallow-water wave, with no
regularity of trochoidal form, with ellip-
J tical orbits becoming rapidly distorted and
the motion of the particles following no
law but accidental combinations of local
circumstances of wind, tides, currents
and countercurrents combined with the
chance influences of irregularities of the
bottom.

Once the deep-sea wave has passed
beyond the second stage, no reliance can
be placed on the motions that are taken
up by the particles and it is equally
impossible to conclude how much of the
energy of the wave while in the trochoidal
form has been transmitted to the final
surf wave. The energy of motion of a
given wave form, which advances into
shallow water or through a narrow
inlet, is successively communicated to
smaller and smaller bodies of water and
there is a tendency to throw the whole
body of water into more and more violent
agitation. Energy thus expended may
occasionally be transmitted forward in a
stated wave form, but the chance is that
it is counteracted by losses of energy
which take place in the formation of
eddies and surge at sudden changes of
depth and irregular friction of the
bottom.

The dynamic principles of the tro-
choidal-wave theory, now so generally ac-
cepted, were first advanced by Professor
Rankine, but the credit of extending the
results to formulas of the horsepower of
deep-sea waves belongs to Lieutenant
Stahl,* United States Navy, from which
formulas he has constructed a table of
the total energy of deep-sea waves in
terms of horsepower per foot of breadth
for waves 25 to 400 feet long, and for
ratios of lengths to bights of waves vary-
ing from 50 to 5.

In referring to this table it should be
borne in mind that it is intended to ex-
press the gross theoretical horsepower
resulting from computation of the com-
bined kinetic and potential energy of
deep-sea waves. For reasons already
stated the full energy of the deep-sea
wave cannot exist after the wave has
come into shallow water. One must not
overlook the fact that the wave motions
in shallow water so completely neutralize
each other as to obliterate the relative
amount of energy obtainable in shallow
water from deep-water waves of different
sizes. Therefore the table of horsepowers
of deep-water waves can hardly be re-
garded as a measure of energy resident
in shallow-water waves. Hence, in con-
struction and application, wave motors
which are to be used in shallow watei^
depend almost entirely upon the lifting
power of the waves, their hight, frequency,
chance circumstances of locality and
weather conditions.

•rrn»ii«nrf(on«. Amfrlmn BotIpIv of Mo-
rlmniriil Fneln«wr«. Vnl Xflt. pnir<> 4.''.».

Any energy received from lateral mo-
tions, being the resultant of other mo-
tions which in the main tend to neutralize
each other, can only occasionally produce
energy suitable for transmission in the
form of useful power and this with but
feeble effect. The total energy obtain-
able as power from shallow-water waves
per foot of shore line can, therefore, be
but a small fractional part of the energy
per foot of breadth of the deep-sea waves
out of which the shallow-water waves
originate and the power derivable from
shallow-water waves is practically con-
fined to the utilization of their lifting
power. This statement applies most par-
ticularly to wave motions in waters where,
from shallowness or irregularities of the
bottom or other causes peculiar to the
location, the trochoidal orbital motion has
disappeared.

The proportion of original kinetic en-
ergy which may have passed into poten-
tial energy and which is available as
lifting power will vary with different
locations and will be variable for a given
location. Nothing can be predicted gen-
erally of the lifting power which can be
realized under these conditions. In
determining the feasibility of installing a
wave motor in waters of this kind, con-
ditions peculiar to the locality should be
studied separately. Observations of the
site should extend over a number of sea-
sons.

There are some locations where the
orbital characteristics of the deep-sea
wave continue on into waters that are
shallow enough for establishing wave
motors. This may be at depths of 20 to
40 feet where, as illustrated in Fig. 6,
the upper trochoidal layers have had
their circular orbits of the deep-water
wave converted into elliptical orbits and
most of the orbital energy of the deep-
water wave may be regarded as con-
tinuing in the elliptical orbits. It has
been proposed to utilize this orbital en-
ergy by intercepting the "to and fro"
motion of the "distorted verticals."

One of the main difficulties attending
this proposition would seem to lie in the
fact that in depths where it would be
reasonable to erect and maintain wave
motors, a large proportion of the original
deep-water orbital energy is at or near
the bottom and the upper trochoidal
layers have only about the same orbital
energy which they had before the orbits
psssed from circular to elliptical forms.
Under these circumstances, an intercepter
of the orbital energy, in the form of
a "paddle" or other resisting surface,
would have to be hinged at its lower end,
or be guided in some manner causing it
to move parallel with the motion of the
wave. In cither case, it is difficult to
conceive of a mechanism by which more
than about one-half of the orbital energy
of the wave could be thus intercepted,
even though the direction of waves were
constant.

Mathematical discussion of the energy
of the complete trochoidal wave goes to
show that one-half of the total energy
is kinetic and one-half potential. Hence
not more than one-fourth of the total
wave energy per foot breadth of wave
could in any probability be opposed by
mechanism designed to receive the kinetic
energy of subsurface particles. Un-
doubtedly the most efficient form of sur-
face for thus receiving the kinetic en-
ergy would be plane surfaces placed nor-
mal to the motion of the wave and mov-
ing with it; hence if constrained to
operate on fixed guides or to swing on
fixed pivots they would lose orbital en-
ergy for any change of direction in the
travel of the waves.

There are two additional considera-
tions: Efficiency of the surface for re-
ceiving the kinetic wave energy and effi-
ciency of the mechanism for conver-
sion of the effect into useful power.
As to the former, it is generally con-
ceded by hydraulic engineers that the
kinetic energy of a current, received on
a submerged surface, varies according
to no known law for a given depth of
submergence, velocity of current and size
or form of surface: the efficiency has to
be determined by experiment for each
particular case. At best, the greatest en-
ergy to be derived is from the surface
particles or those at very moderate depths
of submergence, traveling at uniform
velocity, and by plane resisting surfaces
placed normal to the current and travel-
ing with the current at half of its veloc-
ity. Poncelet determined that with plane
surfaces submerged and moving in this
manner he could realize 40 per cent, of
the kinetic energy of the intercepted cur-
rent.

Applying this to the interception of
one-half of the kinetic energy of the
wave, under most favorable circumstances
only 20 per cent, of the kinetic energy of
the wave for propelling the intercepting
surface would be realized. Any rugged
form of apparatus likely to be adapted
for a wave motor could hardly be ex-
pected to convert more than three-fourths
of this energy into useful power; that is,
not over 15 per cent, of the kinetic en-
ergy of the wave. Hence, with means for
harmonious absorption of kinetic energy,
no more than 1' .■ per cent, of the total
energy of the trochoidal wave can, in any
probability, he utilized. The chances of
obtaining power from "distorted verticals"
are therefore founded on a very narrow
margin which is much too small for
commercial encouragement in the de-
velopment of wave motors designed to
obtain power from subsurface energy. It
must be concluded that the feasibility of
obtaining power from ocean waves is
practically limited to their lifting power,
but, in any event, the power available per
foot of shore line will depend upon
peculiarities of the location and weather
conditions.

590

POWER

October 17, 1911

The Best Standard Voltage and

PVequency for Three Phase

Turbo Alternators

Bv L. P. Crecelius

The present tendency toward in-
creasing the speeds of turbines for the
dual purpose of better steam economy
and lower cost, requires of a relatively
small amount of iron and copper a large
l<ilowatt capacity, because the high speed
demands a reduction in diameter of the
elemental revolving parts. Therefore,
designers find it difficult to provide the
necessary space in large generators for
high-voltage insulation, and this situation
becomes more and more acute with the
increased capacities now demanded and
has brought up the suggestion from
builders to limit the voltage of large
generators to 6600 volts and to use step-
up transformers.

The first step in analyzing this ques-
tion is to determine the most economical
and satisfactory transmission voltage for
general utility on power-consuming sys-
tems which are so situated as to require
the power plant located within 50,000
feet of the substations. Included in
this class are those systems supplying
centers of population of 200,000 or over
in which it is not only desirable but
advantageous to generate directly the
transmission voltage. Excluded from
this classification, obviously, are those
systems depending upon a power supply
so remote from the substations as to
require transmission voltages higher
than are ordinarily considered safe for
underground transmission. In the latter
case it is only necessary to determine
the most economical transmission volt-
age, then to select the generators of the
voltage corresponding to lowest cost, be-
cause step-up transformers must neces-
sarily be supplied to take care of the
difference in voltage between the two.

In the systems included in the first
case, the average length of transmission
cables is less than 30,000 feet and none
averages more than 50,000 feet in
length, although in a few cases a small
amount of power is transmitted over
greater distances. Accordingly, the ac-
companying tables have been prepared
to determine the most satisfactory stand-
ard transmission voltage. In arriving at
the relative costs, the cost of three con-

•1 Toni a impor rond at the mpelins of tlip
Ameilcnn Klc<trlc Uailwav KiiKinpeiins; .\s-
sociation. October n to 13, 1911.

ductor, paper-insulated cables has been
used, based on 5 per cent, energy loss,
unity factory power, and 30 degrees
'Centigrade I rise in temperature, cor-
rected to comprise the nearest commer-
cial size, and due allowance has been
made for spare cables and conduits.
For comparison the usual and standard
generator voltages have been used.

These figures indicate that 11,000
volts is the most satisfactory standard
transmission voltage for most power-
consuming systems requiring large
steam turbo-alternators. The small gain
in cost noted in favor of 13,200 volts
does not seem to be enough to justify
its use solely from the standpoint of
economy or cost of the transmission sys-
tem.

Having established the proper trans-
mission voltage, it becomes necessary to
determine the voltage of the generators,
and considerations of simplicity and
economy demand that it be the same
as the line voltage if possible. To
eliminate damage from short-circuits
and to improve the stability of the sys-
tem as a whole, operators are now seri-
ously considering the introduction of
some form of reactance between the
generators and the distributing cables.
It has been suggested that this protec-
tion would be secured by voltage com-
pensators designed to include the neces-
sary reactance, and within reasonable
limits this is possible; also, that the
generator windings consequently would
not be subjected to potential stresses
caused by line disturbances. However,
this offers no protection in case of in-
ternal trouble in the transformer. On
the whole it does not seem desirable to
add voltage-changing transformers for
the purpose of introducing more reac-
tance to the circuit.

The proper protection can be best se-
cured by connecting the necessary cur-
rent-limiting reactances (with nonmag-
netic cores) between the generator and
busbars and this reactance should have
a value of approximately 6 per cent.

The consideration of cost' has a de-
cided influence on limiting the voltage
of large turbo-alternators directly
coupled to turbines, while the engineer-
ing features involved in considerations
of the efficiency of the steam end *at
speeds required for 25-cycle work con-
stitute the limits between which the de-
velopment of large directly coupled
turbo-generators at 11,000 volts must
stop.

In the reaction type of turbine the
difficulty caused by the effect of the
weight of the rotating member in deflect-
ing the long shaft required for slow-
speed machines has been largely over-
come by substituting a short impulse
section in the revolving element for the
longest and least efficient section con-
taining principally the small blading.

REL.\TIVE CO.ST OF TR.XNS.MISSIOX
.■^VSTEMS UNDER DIFFERENT

CONDITIONS

liislaiu- from
C-Uf rating
station to
Sulistations

Transmission
Voltage

Relative Cost
of Transmis-
sion S.vstem,

Including
Cables and

Conduits

L'O.OOOft

6,600
9,000
1 1 ,000
13,200

126^r

L>i) 000 ft

L'0,000 ft

103'-r

6,600
9.000
11.000
13.200

:so.ooo ft

:io,ooo ft

■■iO.OOO ft

102'-f
100 '7

10,000 ft

40,000 ft

6,600
9,000
11,000
13.200

161^^

117"-;

10.000 ft

IDS'-;

.".O.dOll ff

.-ill. 11(11) ft

.-.11.11(10 ft

.-.11,11(111 ft

6.600
9,000
1 1 .000
13,200

I86<~r

135<~-c
104<-r

100'-;

Another change was made by dividing
the flow of the steam and directing it in
opposite directions from the point of in-
troduction, which eliminates the neces-
sity of some of the dummy pistons re-
quired to balance the end thrust, thus
substantially decreasing the weight of
the revolving element. In the impulse
type of turbine large diameters required
by slow speeds have been successfully
used in a design peimitting the use of a
long shaft operating vertically, the
weight being taken up by a step bearing.
In reference to frequency, little can
be said in this report which would in
any way affect the situation as it now
stands relative to this question. For
purely railway work the use of 25-cycIe
rotary converters is decidedly preferable
and outweighs every other consideration.

October 17, 191 1

P O VC' E R

591

In fact, large lighting and power com-
panies have found the frequency of 25
cycles most advantageous and, therefore,
consideration of the specific advantage
resulting from the use of' a higher or
lower frequency is entirely immaterial.
The use of a three-phase star-con-
nected 11,000-volt 25-cycle generating
system, with grounded neutral, seems
particularly advantageous for conditions
existing in the average American city of
over 200,000 inhabitants where the
power is generated by means of steam
turbines, and it is a debatable question
whether this does not constitute one of
the principal limitations of large turbo-
generators.

Induction Motor Troubles
By H. M. Nichols

The failure of an induction motor to
operate properly may be due to troubles
occurring either outside or inside of the
motor.

Of the first class, troubles occurring
most commonly are incorrect frequency
or voltage, wrong connections, overload.
broken leads or blown fuses. The two
latter might occur in unsuspected places,
such as inside of the compensator or the
motor frame.

Low voltage is the most frequent ex-
ternal source of trouble. This may be
due to any of several causes, such as
too small a transformer, too small wires
leading from the transformer to the
motor, or low voltage at the transformer
primary terminals. In testing for low
voltage, measure the voltage at the motor
terminals as soon as the motor is thrown
on the line; although the no-load voltage
may be all right, when the motor is
thrown on the line the heavy starting cur-
rent taken may pull the voltage down too
low if there is not carrying capacity
enough in the transformer windings and
the line. In considering the sizes of
transformers and lines for induction
motors, allowance must be made for the
excess in starting current as compared
with the running current. In some makes
of single-phase motors the starting cur-
rent will exceed the running current by
as much as 200 per cent.

The troubles that occur within induc-
tion motors are more numerous than the
external troubles, but they are not as
likely to develop as the latter. The most
common of the internal troubles are
faulty insulation, uneven air gap due to
springing of the shaft or shifting of the
motor bearings or to excessive wear In
the hearings, which allows the rotor to
run closer to the lower half of the siator.

Loose laminations may cause the motor
to give out a disagreeable hum. To test
for this, try pushing the blade of a pocket
knife between the laminations.

Vibration may be due to a sprung shaft,
unbalanced magnetic pull caused by an
uneven air gap. or eccentricity of the

rotor; in the case of direct-connected ma-
chinery the vibration may be transmitted
from the driven machine to the motor.

If a wound-rotor machine refuses to
start, the rotor may be open-circuited.
This can be distinguished from blown
fuses. and open circuits in the stator or
leads by connecting an ammeter in the
line; if it shows current flowing in each
of the phases, the trouble is in the rotor.
If there were open circuits in the stator
or one in one of the leads, no current
would flow in the affected lead.

In a three-phase motor if one phase of
the rotor winding is open-circuited when
the motor is running light, the currents
in the three main leads will be nearly
balanced, but if the rotor is held sta-
tionary and a voltage of about 25 per
cent, of the normal is applied, an un-
balancing of the currents taken in the
three stator leads will be observed. The
amount of this unbalancing will depend
on the exact position of the rotor. It will
also be noticed that when starting the
motor it has a decided tendency to re-
main at one-half the rated speed.

If one phase of the stator is open-cir-
cuited in a Y-connected three-phase
motor, the motor will not start by itself
and if started mechanically it will operate
as a single-phase motor, with a pro-
nounced lack of powfer. Current read-
ings can be obtained in only two of the
three-phase leads. If the motor is delta-
connected, currents will flow in all three
leads but they will be unbalanced.

A short-circuited coil in the stator will
cause it to buzz and hum, and if the
motor is run for any length of time the
coil will overheat and smoke.

If one phase of the stator winding is
reversed, the motor will probably refuse
to start under a load, because the torque
will be reduced to about one-third what
it should be, and. when the motor is run-
ning, the currents in the three leads will
be badly out of balance.

Motors requiring extra resistance in
the rotor circuit for starting will not start
with all of this resistance cut out of the
circuit.

Direct Current Turbo-Gener-
ators F,ar^er Tban 500
Kilowatts Capacity

By R. a. Dyer

Information on this subject was re-
quested of the various electric companies,
and the reply of the Westinghousc Elec-
tric and Manufacturing Company covers
the situation very thoroughly. It Is as
follows:

This company has constructed a num-
ber of .SOO-kilowatt direct-connected
units operating at I.VKI revolutions per
minute, but has not built any 600.volt

•Kxlnirn frnin n pii|>iT r>-ni1 licfnrc 111"
Amprlrnn f;i.rirlr llnHwnv Knidn^rlng A.-
porlnll'in. <irl«it«T l> lo 1.1. IIHI.

railway sets of greater capacity, nor ever
entertained any serious requests for bids
on the same. According to information
taken from the technical press, units up
to 750 or 800 kilowatts at 250 volts, and
up to 1500 kilowatts at 600 volts have
been built by European electrical con-
cerns. The average speeds of such size
units are in the neighborhood of 1500
and 1200 revolutions per minute, respec-
tively. The fact that such machines are
built, and are running, disposes once for
all of the question of the possibility of
these sizes. On the other hand, the
small number of such machines in oper-
ation and the experience of the manu-
facturers in this country, seem to indicate
that the demand for them is not great.
This, again, would indicate that there is
no particular improvement over slow-
speed apparatus in one or more of the
essential features, that is. price, floor
space, economy and maintenance.

There are several difficulties in the
way of building direct-current units of
large size. It is essential that carbon
brushes be used on all direct-current ma-
chines, and experience has shown that
the limiting commutator speed for car-
bon brushes is in the neighborhood of
tiOOO to 7000 feet per minute. This at
once fixes the outside diameter of the
commutator for a generator for any given
running speed. The radiating surface of
any commutator fixes the current-carry-
ing capacity. With the best grade of
carbon brushes and a peripheral speed
of from 6000 to 7000 feet a minute it is
known that about 1'4 amperes per
square inch of commutator surface is
about the safe upper limit. To show
briefly how this works out, consider the
case of a 750-kilowatt, 250-volt machine
at about 1500 revolutions per minute
with 6000 feet per minute peripheral
commutator speed. The periphery of the
commutator would be four feet and at
1'4 amperes per square inch of surface,
it could handle 60 amperes total per inch
of commutator length. For 3000 am-
peres, the machine would require two
commutators, each 25 inches in length
on its working face, or from 30 to 35
inches in over-all length; therefore, the
distance taken up along the shaft for
the commutators alone would be six feet
approximately.

Adding the armature core and its con-
nections, a distance of 10 feet 6 inches
to 1 1 feet would be necessary from cen-
ter line to center line of the bearings.
The commutator diameter would be ap-
proximately 15 inches, and it is evident
that the shaft could not be made more
than 10', to II Inches in diameter. With
the center distance fixed, this size ol
shaft would be probably too weak foi
safe operation and it would undoubted^
be necessary lo Increase the commutator
speed to 7000 feet per minute.

The above shows that we are very
near the limiting figures in every par-

592

POWER

October 17, 1911

ticular in order to obtain a speed of
1500 revolutions per minute for a 750-
kilowatt direct-current generator at 250
volts. The speed of 1500 revolutions
per minute is not high enough, however,
to give the most desirable working con-
ditions in the turbine, from the stand-
point of steam economy. Such a unit
is, therefore, a compromise at both ends.
The speed is higher than is desired for
the generator, giving increased friction
and windage losses and reducing the ef-
ficiency somewhat, and also increasing
the cost, while a cheaper and more ef-
ficient steam end could be built if oper-
ated at a higher speed. There is no
doubt that direct-current turbo-gener-
ators of larger capacity than 500 kilo-
watt can be built. How much larger
capacity depends upon the voltage at
which they are to be built; 3000 amperes
is in general about as large a current as
it has been attempted to handle.

LETTERS

Using a Direct Current Ala-
chine as a Generator or
as a Motor

Mr. C. C. Hoke's switching arrange-
ment described in the August 15 number
of Power is used to a considerable ex-
tent for starting alternating to direct-cur-

•■cga-;.e
Equalizer
Posifive

and if it is desired to change an existing
panel so that a generator can be properly
connected as a motor, it will probably be
cheaper to add the three additional con-
tact jaws than to buy new single-pole
blades and handles to replace the old
blades and cross-bar. It is usual to use a
multi-point starting switch and separate
resistance, except occasionally for capac-
ities below 100 amperes, when the stand-
ard starting rheostat is used.

The generator connections are made by
closing the circuit-breaker and three
single-pole switches, when the machine is
at the proper voltage; the starting switch
is left open. The connections for using
the generator as a motor are made by
closing the circuit-breaker and switch in
the negative lead, and then cutting out
the resistance, step by step, with the
starting switch. The switches in the posi-
tive and equalizer leads are left open.

Fig. 2 shows the difference in con-
nections when using three single-pole
switches, as just described, and a three-
pole double-throw switch.

The ammeter, if of the permanent mag-
net type, should be made double reading,
with the zero point in the center of the
scale, because the needle will deflect one
way when the machine is used as a gen-
erator and in the opposite direction when
it is used as a motor.

If used as a motor frequently, and it is
desired to have protection in case the
power goes off the busbars, a low-voltage
release attachment can be used in con-
nection with the circuit-breaker.

.^s equalizer leads are frequently in-
stalled of smaller capacity than the posi-

Sfarfin^
Switch and

Resistance

Field Rheostat

Fig. 1

rent motor-generator sets and rotary con-
verters from the direct-current end, in or-
der to avoid the line disturbances due to
the heavy current required for alternat-
ing-current starting. The connections
usually are considerably simplified as
compared with those given by Mr. Hoke,
and only one panel is used, with the
connections arranged as indicated in the
diagram. Fig. 1.

It will be noticed that three single-pole
switches are used instead of a three-pole
switch. A double-throw switch would be
required if a three-pole switch were used,

Fig. 2

tive and negative leads, it will be well to
see that they are of sufficient capacity if
a change is made.

If the intention is to make a temporary
installation to take care of some emer-
gency condition, the change can very read-
ily be made by using the connections as
given by Mr. Hoke. This will not make
necessary any change in the switchboard
apparatus and will therefore avoid spoil-
ing the appearance of the panel.

The two methods of connection given
are but few of the many combinations
that are frequently of value in various

installations. For machines of large ca-
pacity, one arrangement permits the use
of a starting switch of one-fourth to one-
third the ampere rating of the motor, the
switch being short-circuited after the mo-
tor is up to speed.

A. L. Harvey.
Wilkinsburg, Penn.

A Reversal of Polarity

One Monday morning, on being called
to the nickel-plating room to investigate
some trouble, I found that the current
in the tanks was flowing in the wrong
direction. It was plain that the polarity
had reversed and as the 6-volt generator
which supplied the current was separate-
.y excited from the 110-volt lighting cir-
cuit, I remedied the trouble by simply
exchanging the leads to the field-magnet
coils.

Our factory occupies three buildings
and the power equipment consists of two
Edison machines of 60 and 25 kilowatts
respectively, belted to a Corliss engine,
and one 50-kilowatt direct-connected gen-
erator. The Edison machines carry the
load of two buildings, in one of which the
nickel-plating room is situated, the other
generator taking care of the third build-
ing. A switch is provided on the panel
board by means of which the whole load
may be thrown on either pair of busbars;
this is used in an emergency, should any
of the generators break down. On the
day before, some repairs had been made
to a line shaft in the building where the
nickel-plating room is situated which ne-
cessitated the use of lights, and the en-
gineer had found it expedient to run
the 50-kilowatt direct-connected gener-
ator, using the emergency switch to con-
vey the current to the busbars of the
other building.

Having drawn my conclusions, I
pumped the engineer until he admitted
having forgotten to pull the main switch
of the 60-kilowatt Edison machine, which
caused the current generated in the
direct-connected machine to flow back-
ward through the field-magnet coils of the
belted one, reversing its polarity. The
armatures were not injured because our
practice is to lift the brushes off the com-
mutator at every shutdown, and that had
been done on the belted machine. Of
course, the "problem" turned out to be
no problem at all. but it kept me puzzled
for some time.

R. DUPRE.

New York.

In the demolition of an old gasometer
in Hamburg, Germany, built about 1852.
the iron anchor bolts encased in cement
concrete were found to be as fresh and
bright as new iron, and having no traces
of rust. This is an attestation of the
preservative qualities of concrete and
is a remarkable record.

October 17, 191 1

POWER

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TV %.

A Producer Gas Canal
Tugboat

Many attempts have been made to dis-
lodge the ancient and more or less honor-
able mule from the one job in which he
has seemed to be impregnable — that of
towing canal boats. Even the flexible
and potent aid of electricity, in many
modes of application, has been invoked
vainly. The mule has continued to enjoy

Everything"
n^-orth while in the gas
engine and producer
industry will be treated
here in a way that can
be of use to practi-
cal men

JLMk

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1

Fic. 1. Producer-gas Tugboat

his tranquil supremacy as a canal-boat
prime mover.

Within the past four months, however,
a serious dent has been made in mule-

is a tugboat propelled by producer-gas
power.

Fig. I, giving a broadside view, indi-
cates the simplicity of the outflt by the

gives an idea of the arrangement of the
power plant within the hull. The boat is
41' J feet long, overall, 10'.. feet beam
and floats 5'.. feet above water, over the
engine-room ventilating hatches; the
draft is 4' J feet.

The power equipment comprises a
four-cylinder vertical engine with cylin-
ders 8'_.xl2 inches each, working on the
four-stroke cycle; a gas generator 54
inches in diameter (outside I, a hori-
zontal wet scrubber, a dry purifier and a
water-circulating pump. The generator
is of the simple updraft type, with a
vaporizing "pan" in the top, as shown
in Fig. 5. and the wet scrubber is built
with vertical baffles and is filled with
coke; see Fig. (5. The fuel is anthracite
pea and the engine develops 65 horse-
power at 300 revolutions per minute,
using the gas made from this fuel..

Coal is carried in a little bunker near
(he bow of the boat and the generator is
charged and poked from the deck. The
coal bunker and the charging hopper
of the generator may be seen in Fig. I.
When this picture was taken the attendant
was in the act of poking down the fuel
bed.

There is nothing radical in the design
of the apparatus; the horizontal disposi-
tion of the wet scrubber is the only im-
portant departure from established prac-
tice in stationary plants. The engine is
connected to the propeller shaft through
a clutch and reversing-gear transmission,
but the gear is used only to reverse the
propeller; speed changes are obtained by

Fig. 2.

Gas-pom PR Ti '. in Siwvk.i:

Fig. 3.

power monopoly by the unassuming, even absence of stacks or other evidences of throttling the engine. On the occasion
commonplace-looking, craft illustrated machinery; Figs. 2 and 3 show the illustrated by the photographs, when the
by the accompanying engravings; this "critter" in actual service and Fig. 4 writer was on board, the engine was re-

594

POWER

October 17, 1911

peatedly throttled down to about 100
revolutions per minute. An ordinary fly-
ball governor, arranged exactly as in sta-

vhich is capable of winding in 100 feet
of line a minute.

Two of these tugs have been in regu-
lar service since May 30 on the Lehigh

Malleable Iron Company, and built by
the Salisbury (Md.) Marine Construc-
tion Company. Both of the boats made
the trip from the shipyard to Bristol un-

FiG. 5. The Generator

Fig. 6. The Wet Scrubber

tionary practice, is provided to take care
of the speed when the clutch is thrown
out.

The water for the engine jackets and
the producer is supplied by a four-cylin-
der pump driven from the engine shaft
by bevel gears. The pump cylinders are
3x3' J inches and the speed is one-fourth
the engine speed. There is also a small

canal between New Hope and Bristol,
Penn., a distance of 26 miles. Each tug
hauls four or five 100-ton barges over
the route at a speed of about 4 miles an
hour and consumes 56 pounds of pea
coal per hour. The "schedule" time for
the round trip of a single barge towed by
two mules is about a week.

The tug equipment w-as designed by

der their own power and pulled through
some rather heavy weather in Chesapeake
bay with no operating difficulty.

.■\ locomotive of 1000 horsepower driven
hy a Diesel engine has just been set to
work on the Prussian State Railways.
The drive is direct to the axles and the

Fig. 4. Showing the Arrangement of the Power Plant in the Hull

air pump which maintains the pressure Wilhelm R. Huttinger and was built by outward appearance is similar to that of

in two tanks containing compressed air the Trenton Malleable Iron Company, an electric locomotive. Nearly 560,000

for starting the engine, and a power The boat was designed by W. H. Walton, have been spent in experimenting with

winch, driven by a Morse silent chain, of the gas-power department of the this engine.

POWER

Important Engine Tests

Most engineers admit the importance
of tight valves and pistons when economy
is desired, but they neglect to make the
few simple tests of ascertaining the real
conditions.

The engines may be indicated regular-
ly, the plant run in a supposedly intelli-
gent manner, all of the recording de-
vices carefully watched and yet the op-
erating costs mount up. The owners call
in a specialist and he traces the trouble
to the engines and finds them leaking
badly; he discovers a situation of which
the engineer should have been cognizant.

Engineers should make these tests at
least once a month. An engine piston
may be tested for tightness by placing
the crank at either dead center, the valve
gear remaining hooked in. As the en-
gine cannot move off its center, the throt-
tle may be opened wide, and the head of
the valve will admit steam behind the
piston into the clearance space. To prove
that steam is there, merely open the in-
dicator valve at that end of the cylinder.
Then close this indicator cock and open
the one at the opposite end of the cyl-
inder. If steam appears at this end it
must have passed the piston and there-
fore proves a leakage. As this is a very
severe test, a gentle flow of steam should
not be considered seriously, but should
a strong head be emitted it is positive
proof of a leaky piston.

The remedy is to set out the piston
rings or renew them. For bad cases, re-
boring the cylinder and fitting it with new
piston rings may be necessary.

To test admission valves for tightness,
unhook the valve gear and place the ad-
mission valves so as to cover the steam
ports at both ends of the cylinder. This
will prevent steam from getting into the
cylinder if the valves are perfectly tight.
Either indicator connection will show
whether the foregoing condition obtains.
This test does not require that the piston
should be on a dead center; it may be
made at any point in the stroke. There-
fore, the tests can be made at any time
when the engine is not in operation and
should be made weekly.

When testing the exhaust valves, place
each valve so that it will cover the
port on the end of the cylinder be-
ing tested and then admit a full head of
steam into the cylinder. If any steam
appears in the atmospheric exhaust, the
valves arc leaky. This lest can also be
made in a few minutes at any shutdown.

Any operating engineer can make the

foregoing tests without rendering the en-
gine inoperative for more than a few
minutes. As valves and pistons must
necessarily wear and become leaky in
continuous operation, these trials of en-
gine valves and pistons for tightness
should always supplement the other im-
portant engine-room test^

Charles Thomas.
Jersey City, N. J.

Temporary \'al\e Repair

The accompanying sketch shows how
a disabled valve was made to do tem-
poran,' service. One morning the watch-
man informed me that one of the valves
in the boiler-feed line would not close,
and. as a consequence, he had to blow
down the boiler several times in order to
maintain a proper water level.

How THE Valve Was Made to Work

I examined the valve and found that
the thread in the valve stem was so
worn that the stem would not hold the
valve disk to its seat. I obtained a
piece of ^-i-inch round -iron and bent it
as shown in the sketch. It was sawed
lengthwise about one-half its length and
the end was spread wide enough to fit
on over the valve bonnet back of the
stuffing nut. The valve wheel was re-
moved and the point of the threaded
screw was seated in the end of the
valve stem. As the screw fitted in a
tapped hole in the outer end of the clamp
I could close the valve at any pressure
by turning the screw and the pump pres-
sure would open the valve when the
screw was backed out.

M B. Warbp.r.

Providence. R. I

Loose Bushing Caused Pound

A cross-compound vertical engine di-
rect-connected to a 500-kilowatt, alternat-
ing-current generator developed a bad
pound which was hard to locate, and the
"doctor" came from the shops to see
where the pound was. He stayed three
days, set the valves and finally said that
the high-pressure crank disk was loose
on the shaft.

We bored a 1-inch hole 6 inches deep
in the center of the shaft, heated the
shaft and drove .n pin into the hole. This
tightened the crank disk but did not stop
the pound.

The chief said that the high-pressure
cylinder had been rebored and I sug-
gested that a possible cause for the
pound was a loose bushing.

The cylinder head was removed and
it was found that the bushing had
sheared the \s-inch dowel pin and was
working with the piston; a i',;-inch space
was also found between the head and
the bushing. The head of the cylinder
was turned down even with the bushing,
and eight ~s-inch holes were drilled and
tapped throughout the walls of the cyl-
inder and bushing, four at the top and
four at the bottom, and pins screwed in
them. This removed the cause of the
pound.

B. Browne.

W.itcrford, Conn.

Experience w ith a Cut Cyl-
inder

A new cross-compound, horizontal con-
densing engine, having a 48-inch low-
pressure cylinder, was recently installed.
The engine was to run at a piston speed
of 800 feet per minute, and great care
was exercised when starting up and a
large amount of cylinder oil of good
quality was used.

In a few days it was noticed that the
cylinder and junk ring were cutting. Upon
examination it was found that the cylin-
der had a number of ugly looking
scratches in the botoni side and that the
junk ring was correspondingly scored.

Not caring to try to operate it further
in this condition, a portable boring bar
was rigged up and the cylinder was bored
out sufficiently large to remove the
scratches, making the cylinder 'j< inch
larger in diameter than it was before. A
new junk ring and packing rings to fit
the rebored cylinder were made. T.-iking
pains to sec that all foreign particles
were removed from the cylinder and

596

POWER

October 17, 1911

steam passages, an abundance of cylin-
der oil was supplied and the engine
started for the second time. In a day or
two about the same kind and depth of
scratches appeared.

The cylinder was again rebored, mak-
ing it % inch larger than the original
size and new packing rings were made to
fit the cylinder. The damaged junk ring
was taken out, turned down '/. inch
smaller than the cylinder and some ir-
regular shaped grooves were cut in it
while it was in the lathe. A ring of
good babbitt metal was cast on the junk
ring, and turned to fit the cylinder.

The engine was put together and ?s it
has been kept going without any diffi-
culty for some time it begins to look as if
a good job had been made of it and that
the cause of the trouble has been re-
moved.

Almon Emrie.

Chicago, III. 1

Low Pressure Cylinder Lu-
bricator

A great deal of trouble was experi-
enced in lubricating the low-pressure cyl-
inder of a large cross-compound Corliss
engine driving a street-railway generator.
Various grades of oils and many dif-
ferent methods of admitting it to the cyl-
inder were tried. The engine, however,
could only be operated with any degree
of success by feeding an excessive
amount of oil, the quality and method

^eceiyer, 10 -to i

Lubricator for Low-pressure Cylinder

of admitting the oil to the cylinder ap-
parently making little difference in its
operation.

The chief engineer finally hit upon the
method shown in the illustration. This
consists of a tee fitted with a nozzle sim-
ilar to that of an injector, the side out-
let of the tee being connected to the oil
tank through the sight-feed glass. A small
amount of live steam only is necessary
to completely atomize the oil which is
blown into the entering steam coming
from the receiver, completely saturating
it before it reaches the low-pressure
steam chest.

The sight-feed attachment was taken

from an old lubricator, and all other parts
were picked up in the junk pile, making
the cost of the complete outfit very small.
Since this was applied the lubrication of
the low-pressure cylinder has been per-
fect, with a minimum consumption of oil.
S. Kirlin.
New York City.

Milling Baffle Plates

An easy way to overcome the bulging
of the baffle plate on the inside of a
furnace door is to run a milling cutter
through the middle of the plate, cutting
it as shown in the accompanying sketch.
These slots are each about 3/16 inch
wide, and allow for the expansion of
the plate; they do not reduce its effi-
ciency materially.

The usefulness of most of these plates
in my case was formerly limited to a
period of not more than three months.
With the changes made in them as noted

Milled Baffle Plate

above, this period has been more than
doubled. Some of the plates which were
put in seven months ago are now doing
duty and are in good condition.

George F. Read, Jr.
Newark, N. J.

Engineer's Reference Book.

I am anxious to develop an engineering
reference book for my own personal use
and I would like to get a few ideas on
how best to go about it. From time to
time I run across facts which are worth
recording for future use. For instance,
I may hear of a particularly high boiler
efficiency. I would like to preserve some
information as to how that efficiency
was obtained, when and where. Again,
I may read of some new type of engine
showing high economy. Then, there are
many items such as the characteristics
and the heat value of the various kinds
and grades of fuel; also, numerous for-
mulas which should be recorded in such
manner and shape as to be quickly avail-
able.

The book should be, I think, of such
size that it may be carried easily in the
coat pocket and it must be of the loose-
leaf variety so that it may be revised and
enlarged with facility.

The chief problem seems to me to be
in arranging the contents and indexing
it so as to be able to find what one is
looking for with the least loss of time.
Phil Lighte.

Brooklyn, N. Y.

Steam Ejector
The accompanying sketch is of a home-
made ejector that I have found very use-
ful. In a certain plant some of the

Design of Steam Ejector

water pipes would invariably freeze and
burst, and cause needless expense.

I did not use steam to blow out the
lead water pipes, but rigged up the de-
vice shown. The steam jet created a
vacuum in the lines and the water was
drawn from them.

H. Prev.

Montreal, Can.

Taper Piston Fit

Some engine builders take extreme
pains to set the piston tight on the rod.
The rods are tapered at the end and the
piston is pressed on as tight as though
the job was to stay finished forever.
There are cases, especially in marine
practice, where the rod end is riveted
over so that the piston can be removed
only after cutting off the battered end of
the rod.

Offhand, many would say that a taper
pin is more easily removed from a hole,
and that a piston can be easily removed
from a taper fit. The idea, however, is
entirely wrong. When a mass of metal
is forced onto a taper fit, it generally
bites and stays fast in a most exasperat-
ing way when one wants to separate the
parts. For small work this bite can be
loosened by quickly heating the sur-
rounding hub or collar and then giving
it a sharp blow. For large pistons heat-
ing is not practical.

One prominent engine builder has
never used the tapered hole in piston con-
struction; he makes the hole in the pis-
ton straight and the rod end enters wit*^

October 17, 1911

POWER

597

an easy, sliding fit — just tight enough
not to wabble. The rod end is turned
down so as to form a ;4-'nch shoulder
for the piston to bed against, and a sin-
gle large nut holds it on. A setscrew in
the nut prevents it from working loose.
This construction made it possible to
easily remove the piston; in every way
this method of fitting seems admirable.
F. W. Brady.
Scranton, Penn.

Shortening Belts in Damp
Weather

While employed as chief engineer in a
large cotton mill in the South, the gen-
eral manager informed me that he had
ordered the millwright and his assistant
to put in a week taking up all of the
belts in the mill, the main driving belt
along with the rest, although there was
but one or two belts which needed tak-
ing up, and very little would do.

All the belts were doing good work.
Not one was slipping, although all
sagged a little, owing to three weeks of
rainy weather. I tried to show that there
was less friction on the shafting bearings
and that the belts would do better work
running a little slack than when too
tight.

He did not like to see them sag, as it
looked bad to visitors from the other
mills who came in to see us quite often.
I tried to induce him to wait until the
weather cleared and the belts dried out
before taking them up for then he could
tell just how much each would stand.
But he would not hear of waiting and
gave the millwright orders to start on
the belts the next morning, and take out
what he thought they would stand.

The bad weather continued during the
two weeks' shutdown, but cleared the
day before the mill started up.

The millwright, by the way, was no
mechanic, merely a laborer who had
helped the millwright before him and
got his job when he left. He cut out
from 6 to 10 inches out of each belt,
or until each was as tight as he could
get It. When I started up, the fun be-
gan. The engine had run but a short
time when both main hearings went hot.
The manager would not have the engine
stopped, but turned water on the bear-
ings and flooded them with oil. He said
that he never had to shut down for a
hot bearing and he was not going to have
me begin; it was carelessness on my
part in not seeing that they were prop-
erly oiled before starting up, or they
would not run hot so quickly, and that
it was no fault of the belt.

He left the engine room to go to his
office, and had only been gone a short
time when he came running back, yelling
at the top of his voice to stop the en-
gine. I had the throttle only half closed
when the engine stopped with a groan.
The boxes on the main driving shaft had

melted out and hot metal was scattered
over the fioor; the main bearing on the
engine stuck fast, one 10-inch belt broke
and several others ran off the pulleys;
and all of the boxes on the main line
shaft, excepting one, had burned out the
babbitt. The owner of the mill chanced
to pay us a visit a few minutes after
the engine stopped and promptly fired
the manager and hired a practical man
in his place.

He put me in full charge of the ma-
chinery and all of the men connected
with its care. I hired a first-class mill-
wright and kept the other as a helper.
It took three and a half days' work in
rebabbiting the boxes and letting out and
splicing the belts before the mill could
be run again.

I have made it a rule that if I have a
belt to shorten, I will do it in dry weather
if possible. Then they are dry and not
stretched out to their full length.

W. V. Ford.

Norwich. Conn.

Macliinerj' Guard

The accompanying sketch shows how
a guard may be made to go around ma-
chinery. The posts are of l.>:tx4-inch
dressed pins. The side strips are ^^-6
inches and are of the same material. For
a 6-foot wheel the frame is made 6 feet

flattened ends for ^x2V2-inch carriage
bolts to secure them to the frames. After
the frames are made they should be
painted to match the color of the engine
and, when dry, cover them with steel-wire
fencing 48 inches wide. I use a fencing
having a mesh of 2x4-inch of No. 12
wire, which can be purchased of any
dealer in fencing.

In case of any work on the machinery
the frames can be moved out of the way,
and there are no projections on the floor
to be stumbled over.

J. P. COLTON.

Ohio City, O.

Graphite Reduces Oil Con-
sumption

In a steam plant where there were a
number of vertical boilers, considerable
trouble was experienced from feaky
tubes and opening of the seams.

Investigation showed that practically
all of the internal surfaces of the boilers
were coated with deposits of cylir ■
oil and scale. The load upon the engine
had been gradually increased until the
limit had been reached, and the engineer
found that to give this cylinder the proper
lubrication no less than y- gallon of the
best cylinder oil must be used. The sug-
gestion that graphite be used as a means

Construction of Machinery Guard

long, 4 feet 4 inches high, and the lower
side strip is set into the posts S inches
from its lower edge to the floor. The
top strip is fastened to the top of the
posts as shown.

For the floor irons use I'i-inch pipe,
cut to the desired length, and after drill-
ing the concrete floor, set the 1 '.4 -Inch
pipe sleeves and cement them in place.
The irons used on the frames are I -Inch
pipe drawn out flat for about one-half
their length. Holes are drilled in the

of reducing the excessive demand for
cylinder oil was adopted. It was used
mixed with the oil in a force-feed lubri-
cator. As a result, the oil consumption
has been reduced .SO per cent.

The oil separator in the exhaust line
is now able to handle practically all of
the oil and there is no more burning of
tubes and plates in the boilers from be-
ing coated.

Edward T. Binns.

Philadelphia. Penn.

598

POWER

October 17, 1911

Stopped the Leaking Tubes Cooling a Hot Crank Pin

There are four 72-inch by 16- foot
fire-tube boilers in tlie plant where I am
employed. Shortly after the boilers were
installed the lower tubes next to the shell
began leaking. They were rolled so
often and got so thin that it was impos-
sible to keep them tight, and new ones
had to be put in.

As the other tubes did not leak, some-
thing was wrong. The sides of the tubes
next to the shell were only 1'/. inches
from it, and this was thought to cause
the trouble; they prevented proper cir-
culation of the water, and the tubes be-
came overheated and expanded unequal-
ly-
Having consulted other engineers and
two boiler inspectors, I took out the bot-
tom outside tubes and put stub tubes in
their places. They were made by taking
tubes of the proper size and about 2 feet
long and welding one end. The welded end
was put in the boiler and the other end
was expanded in the tube sheet just as
though it were a new tube. I have had
no further trouble with leaky tubes.
E. V. Chapman.
Decatur, 111.

Wire in Sight Glass

I always had considerable trouble in
keeping lubricator sight-feed glasses
clean, caused usually by opening the
feed valve before enough water had ac-

WiRE IN Sight Glass

cumulated under the oil to give it a
steady feed.

The accompanying sketch shows an
idea I am now using. I inserted a small
brass wire A, bent as shown, and al-
lowed it to project about os inch above
the top of the feed nozzle. The drop
will always travel to the top of the wire
and never hangs over the sides of the
nozzle.

Edvcard Sobolewski.

Cincinnati, O.

I recently succeeded in cooling off an
obstinate crank pin in the manner shown
in the accompanying illustration. The
engine was slowed down to about 70
revolutions per minute, then the oil cup
was removed and a piece of '4 -inch pipe
about 4 inches long was screwed in its
place. One end of a length of '4 -inch
rubber tubing was slipped over the pipe

Hose Attached to Crank Rod

and the other end was attached to a
funnel. By this means the crank pin
could virtually be given an oil bath and
the normal temperature was soon re-
stored.

E. Hurst.
Boston, Mass.

Wedged the Pipe in Place

The discharge pipe of a steam pump
stripped the threads and blew out of the
flange, as at the point A, shown in the
accompanying illustration. As it would
have taken a day or more to get the nec-
essary nipple and flange to repair it, and
as the pump must be kept running in the
meantime or the mine would be drowned
out, I "spragged" or wedged it. as
shown.

One of the braces was inserted be-
tween the pump and the heavy mine

^77777777777:

How THE Pipe Was Held in Place

timbering and wedged snugly, but not
enough to tilt the pump. After pushing
the discharge pipe back into the stripped
flange, another brace was put in place
and tightly wedged. The wedges were
then nailed to prevent them froin slip-
ping.

Although the joint leaked some, the
mine was kept free of water until the
proper repairs were made.

W. E. Bertrand.

Philadelphia, Penn.

lank Gage

Some time ago the company I work for
erected a new water tank 70 feet high,
and as the gage was attached to the tank
it was difficult to tell how much water it
contained. Therefore I got a piece of
'/. and 2 by 17-inch iron and drilled and
tapped holes for pulleys, studs and wall
bolts. One pulley was made 7 inches in
diameter with a 2-inch pulley fastened
to it. There was also one pulley 6
inches in diameter with another 2-inch
pulley fastened to it; another pulley was

Tank Gage

made 6 inches in diameter to which an
18-inch sheet-iron circle was fastened.

Two shafts were screwed into the iron
hanger and the pulleys revolved loosely
on them. Wire from the tank telltale
was then wound around the 7-inch pulley
and a wire was run from the 2-inch pul-
ley to the 6-inch pulley on the other
shaft. Another wire ran from the 2-inch
pulley over the other 6-inch pulley and
a weight hung to it. This made a reduc-
ing motion, and by pulling the wire out
foot by foot the dial can be marked, the
hand set and then the length of wire
running to the float gage on the tank
adjusted.

J. J. Warner.

New Comerstown, O.

October 17, 1911

P O W E R

599

%1 H^^^^l'T^-'-g-^j ^

Jl

/ ^^i,>

Bleeding Receiver to Heat
Feed Water

George M. Peck, in the issue of Septem-
ber 19, page 445, thinks the article on
"Bleeding a Receiver" is "misleading"
because it says that 903 B.t.u. would
be "available for evaporation" whereas
the heat necessary to evaporate a pound
of water at 24 pounds is 953.5.

Each pound of steam carries into the
high-pressure cylinder 1194 B.t.u., of
which 85 are converted into work in that
cylinder, leaving 1109 B.t.u. to go to the
receiver at 24 pounds pressure. Since
the steam was only dry saturated to start
with, the conversion of some of its heat
to work will result in condensation. The
substance which goes into the receiver
will be a mixture of steam and water.
How much will there be of each?

It will all be at the temperature corre-
sponding to 24 pounds pressure, so that
206 of the 1109 B.t.u. would be used up
in heating it to that temperature. This
leaves

1109 — 206 = 903 B.t.u.
"available" for latent heat or heat of
evaporation, "available" for keeping the
water in the form of steam. It takes
953.5 B.t.u. to evaporate a whole pound
of water at 24 pounds, and since there
are only 903 B.t.u. available there will
be only

—— = 0.947
933-5

of the pound remaining in the evaporated

condition and 100 — 0.053 of the pound

will be in the form of water. If cigars

cost S8 a box and you had only S6

"available" for the purchase of cigars,

you could only buy - = 0.75 of a box

if you stuck to that brand. If it takes
953.5 B.t.u. to make a pound of steam
and you have only 903 B.t.u. to work
with (that is, available), you can make

only ^-^ of a pound. I thought the

95 3 5
former article made this clear, but per-
haps others have, like Mr. Peck, failed
to grasp the meaning.

The division of the load equally be-
tween the cylinders is to secure prac-
tically equal temperature ranges and thus
minimum cylinder condensation. When
the whole amount of steam is allowed
to work in both cylinders, the amount
of work done in each is nearly propor-
tional to the temperature range. It would
be exactly for the Carnol cycle. When
a part of the steam is taken out at the

receiver the work done in the second
cylinder will be proportionately less when
the conditions of equal temperature range
are preserved. The thing to do is to
make the low-pressure cylinder enough
smaller to keep the work sufficiently
equally divided for mechanical consider-
ations with equal temperature ranges. I
have seen a compound engine run back-
ward— that is. with the larger cylinder
connected to the boiler and the smaller
to the condenser — for the reason that so
much steam was taken out of the re-
ceiver that there was only enough left
to run the smaller cylinder with a proper
ratio of expansion.

F. R. L.
New York City.

Lifting Water in Boilers
In the August 8 issue, C. J. Harden
states that he believes the average
boiler explosion is due to the rapid evap-
oration of the water and not to water
hammer when cutting in a boiler having
a higher pressure than carried on the
line.

I believe that in nine out of ten cases
of explosions occurring through cutting
into a line with lower pressure, the acci-
dent would be due to a combination of
these conditions. There is a large quan-
tity of steam liberated from a boiler when
the pressure is suddenly reduced, but
there arc three paths in most boilers for
the egress of this excess steam, the
formation of which is not instantaneous,
although it is rapid. These paths are the
two safety valves and the main steam
main communicating with the other boil-
ers attached to the line.

It may be said that these paths would
be insufficient to carry away all of the
excess steam, but in many cases of ac-
cidents with boilers being cut in on a
line with a lower pressure, with only a
slight difference of pressure between
the boiler and the line, these paths wouli
be ample. If. however, water hammer
occurred at the moment of maximum
pressure in the boiler, due to the sudden

generation of steam, the e.xtra stress im-
posed upon the boiler would probably be
too much for the structure and would
cause an explosion. The stress due to
water hammer is, moreover, an impact,
the effect of which is said to be double
that of a gradually applied load.

John S. Leese.
.\\anchester, Eng.

Further Fxperiences with
Managers

Mr. Case's letter in the September 5
issue is a good example of how thick-
headed and self-important some man-
agers and superintendents are even when
the results of their orders come back
on them. It is only another instance of
the "powers that be" overruling all things
that are right because they do not coin-
cide with their own ideas, and while, as .
Mr. Case says, the owners did not blame
him, yet such proceedings were verj' dis-
couraging, to say the least.

I recall a similar instance of freezing
pipes in a small factory which caused
considerable damage, and if the engi-
neer's warning had been heeded it need
rot have happened.

The mill in question had been operated
under various managements for many
years so that each regime had left some
arrangement of piping or machinery to
remember it by; as all these appliances
had fallen into disuse, they did noth-
ing but occupy valuable space.

Among tnem was an arrangement of
coils of pipe in the chimney so that the
gases would pass through it and heat
either the feed water or that used for the
mill. Not having been used for some
time, it had fallen into the lower part of
the chimney where the soot began to ac-
cumulate upon it.

When the new engineer inspected the
chimney, he saw that if not attended to
in time it must stop up the smoke pass-
age and cause a shutdown. It being
warm weather he wished to remove the
piping and clean out the soot.

When he stated the case to the man-
ager, he was told that they could not stop
now and therefore nothing was done.
Nothing happened until the latter part
of the month of November, when the soot
rose enough to stop the draft, which was
never very strong, and the fires had to be
pulled and the cleaning commenced. The
engineer drained all the pipes in his de-
partment and wished to drain the
sprinkler system, but the manager re-
marked that he guessed that it would

600

POWER

October 17, 1911

not freeze, so the water was allowed to
remain in it. Tlie worl^ on the chim-
ney occupied several days, during which
the weather was very cold. The steam
had not been through the mill but a
short time when the water began to break
out from burst pipes on the ceilings and
most of them had to be renewed.

Later, in the same plant, it became nec-
essary to repair the arch over the large
door in the boiler room and make a new
door. The new frame was put up and
the brickwork finished while the weather
was warm, but the door was left until
some future time. The manager's atten-
tion was called to the matter in ample
time, but nothing was done until one
morning in December. It was then cold
enough to freeze the pipes leading to the
steam gages and one of the boilers, hav-
ing no fire under it, had its blowoff valve
burst. Then the superintendent showed
surprising activity in having a new door
made and hung.

In this instance, as with Mr. Case,
the engineer's advice was sound; but the
manager believed his opinion to be on
such a high plane that no argument could
be advanced by his subordinate to show
that he was wrong. All these unneces-
sary risks were taken wath the resultant
loss of time and money to prove the
fallacy of the employer's directions.

G. H. Kimball.

East Dedham, Mass.

Heat Transmission in Boilers

In the September 12 number, V. L.
Rupp gives an interesting article, which
leads me to explain a simple method to
prove a statement he refers to about more
heat going through the upper flues of a
return-tubular boiler than through the
lower ones.

I sawed a piece of pine board about a
foot long into as many strips as there
were tubes in the central vertical row
in one of our 150-horsepower boilers,
containing 3K'-inch tubes, 18 feet long,
and placed at the smokebox end one of
these strips in each tube all the way up.
At the end of 24 hours I found in the
top tube a strip of charcoal not over one-
half the size of the wood, and in the bot-
tom tube a strip of smoked pine. This
only proved what I had been told, but it
gave me a more comprehensive notion
of the difference, and a pretty definite no-
tion that putting a thermometer in the
breeching only gives an idea as to the
average temperature at which the gases
leave, but no knowledge of the tempera-
ture at which the gases through the up-
per tubes were leaving.

To change this condition, I designed
and had made cast-iron curtains to hang
on the smokebox end of the tubes, cut-
ting off about three-quarters of the upper
row, five-eighths of the second, one-half
of the next, and so on, and a four weeks'
test, alternate on and off, showed .S per
cent, gain with them on. This would

have proved quite satisfactory, had it not
been for the sequel. Thinking to ask
about how it worked a few months after,
nothing could be found of the contrap-
tions, and inquiries showed that they had
to be removed to clean the flues, as I had
known, and, little as it took to hook them
on, that little was a little too much for
the fireman to do, so long as he did not
have to do it.

John E. Sweet.
Syracuse, N. Y.

Boiler Room Repairs

Referring to Mr. Jahnke's letter in
Power for September 19, I have had
many troubles such as he describes with
the through braces. The copper washers
were put on, smeared with a thin mixture
of red lead and oil, and the nuts were
drawn up as tightly as possible. No
further trouble from leakage was noticed.

The door-arch plates in a battery of
six boilers had to be renewed every six
weeks or three months. This was ex-
pensive, so I had the mason use one set
of the old arches and cheek plates as an
experiment, building a solid double-row
firebrick arch over each door above the
plate and not imposing any weight on it.
This gave ample room for the plate to
expand, and as it was not badly burned
it did not weaken, but the fireman acci-
dentally knocked it down and pulled it
out, leaving the firebrick arch entirely
unprotected. The idea was to see whether
the plates would burn back any further
than they had burned already. The arch
held so well that I had the plates taken
out of all of the furnaces.

The iron dead plates would burn out,
and to overcome this each dead plate was
lowered enough to allow a firebrick to
stand on edge upon it, the top edge of the
brick being flush with the bottom of the
fire door and the grate bars. Although
the firing was very heavy in this plant
the door-arch repairs were decreased to
less than one-half of the former cost.

In my present plant I have the arches
made of rounded-corner, or jamb fire-
brick. These make a very good arch and
they last in this plant from two to two
and one-half years. Jamb brick are bet-
ter than the square-corner brick, as the
latter will usually burn off or accumulate
a clinker which must be broken off, leav-
ing the corner jagged. The life of fire-
door arches depends a great deal on the
fireman's care in keeping the fire pushed
back from the doors. In most cases the
fires are carried too heavy and when
slicing the coals will naturally fall out.,
and as the fire is very hot the door is
usually closed as soon as the bar is with-
drawn. This lea^'es a bright fire close
to the lining on the inside of the door
which usually burns out the door lining
as well as the arch.

R. A. CULTRA.

Cambridge, Mass.

Turbine Accident at River-
ton, 111.

Referring to the recent turbine accident
at Riverton, 111., I do not understand how
a turbine of this size may be kept run-
ning at half speed for 10 minutes. It is
not an impossibility, but it seems to me
very improbable. I should want to be
very certain of the evidence of this speed
before accepting it.

I have had considerable experience
with all classes of operating men and
their reports following accidents are fre-
quently erroneous, probably not inten-
tionally so in a great many cases, but
because of their failure to understand all
of the conditions involved and to look
at all of the evidence before arriving at
conclusions. Most of them are very un-
willing to change a decision after hav-
ing once made it, even in the light of ad-
ditional evidence.

I do not quite see how it would be
possible for a bolt or nut to get past the
small clearances of this type of machine
to the shaft, and even though it did get
there the centrifugal force would more
than likely throw this foreign body to
the outside edge of the wheel where it
would damage the buckets instead of the
hub at the center. I am assuming that
the rotors and disks were not disturbed
in the repairs to the machine. For the
burst rotor to get out of the machine it
would be almost necessary to crush the
metal at the packing of the next dia-
phragm.

W. E. Stannon.

Chicago, III.

Sand for Hot Boxes

I was much surprised and enlightened
by the editorial in the August 29 issue
under the above title. It was news to me
that a box of sand is part of the en-
gineer's emergency outfit.

I have spent several years at sea in
the engine rooms of some of cur largest
ocean liners, and I can say that I never
saw or heard of sand being used for
hot propeller shafts. I have often used
graphite, white lead and oil, castor oil
and even sulphuric acid (H^SO. I. I
quite agree with the writer of the editorial
as to the use of Sapolio to tune up new
bearings, as it is only a mild abrasive.
But, when it comes to using sharp sand I
draw the line. Sand contains fine particles
as hard as steel, and its use for a bab-
bitted bearing would be disastrous as
these hard particles would be embedded
in the babbitt and ruin it; in fact, it
might easily mark the shaft.

I am ';fvaid that if the writer of the
aforen.t;itioned editorial was employed
on some of our ocean liners and used
•;iiarp sand on the propeller-shaft bear-
ings to cool them off, he would have
the chief down on him with a vengeance.

R. HOWARTH.

Centerdale, R. I.

October 17, 1911

POWER

601

Mr. Bullard's Diagrams

In the issue for September 19 are
shown a pair of diagrams, from a Whee-
lock engine, submitted by W. H. Bullard.
The crank-end steam valve opens and
closes too soon. The early opening can
. remedied by increasing the distance
tween the catch plate and the center
the pin by which the crab claw is at-
.,;ed to the wrist lever, in the following
anner: If Mr. Bullard will examine the
rin just referred to. he will find that it
carries an eccentric, which can be re-
volved, for the purpose of adjusting the
length of the crab claw. To cause a later
opening of the valve, the length should
increased. No doubt this can be done
.Mr. Bullard with no further instruc-
ts, provided that in making repairs a
-.light pin has not been substituted for
_ eccentric one; otherwise the remedy
IS to replace the eccentric pin so that
proper adjustment can be made.

After this adjustment has been made,
r. Bullard should adjust the length of
... rod between the governor and the
knock-off cams to equalize the cutoffs.
He will find that this rod should be
shortened. Just how much adjustment
will be required, can only be determined
by experiment in connection with the in-
dicator.

From the exhaust lines of these dia-

ims, I am led to believe that the econ-

y of the engine could be improved by

earlier release, as the condenser does

not take hold as promptly as it should.

This can be had by advancing the ec-
centric in the direction in which the en-
gine runs, after which a slight adjust-
ment of the eccentric rod to equalize
compression should be made. The steam
valves also will probably require ad-
justment to avoid too early admission.
Charles F. Prescott.
Philadelphia, Penn.

To Prevent Standpipe
Freezing

Referring to the query in Power of
September 12, page 411, the most effective
way to prevent freezing of water pipes
exposed outdoors is to apply sectional
cork pipe covering.

If the pipe is rather large, a good
homemade, inexpensive job can be done
by building a wooden box or casing around
the pipe, keeping a distance of 6 inches all
around by means of split wooden col-
lars, closing in the rianges, fltlings and
bodies of valves the same way. There
must be no possibility of pipe joints
leaking; all must be dry and preferably
painted. The space between the box and
the pipe is then filled with dry. regranu-
latcd cork, with grains of about '4 inch,
packed to a density of 7 to 8 pounds
per cubic foot, leaving no spaces unfilled.

When exposed to the weather unpro-
tected, shrinkage cracks form In the cas-
ing, thus allowing the moisture to reach

the insulation and rendering it ineffective.
It must therefore be made water tight
by inclosing it in a heavy cemented roof-
ing jacket; or better, in sheet metal,
soldered up.

Charles H. Herter.
New York City.

Mr. Rockwell's Questions

I believe no one man can answer, with
absolute certainty of being correct, the
questions asked by H. R. Rockwell in
the September 12 issue. I will try to
answer one.

.\t the Canadian General Electric Com-
pany's plant, some years ago, a blowoff
cock on one of the boilers was lo-
cated in a position very difficult to reach;
it was between the back wall of the
boiler house and that of the boiler set-
ting. One day after the cock had been
opened to blow down a couple of inches
of water my attempts to close it were not
successful. The plug had become stuck
and as there was only about 14 inches
of space between walls, very little pres-
sure could be put upon the valve handle
on account of the position in which I
had to stand in the narrow space.

Failing to close the valve, I hustled out
and drew the fire. In a short time the
boiler was empty. The cock was re-
moved and another one was put on in a
few minutes after the boiler was empty
and the superintendent gave orders to
fill up the boiler and get up steam danger
or no danger, his reason being that
several departments were idle, including
about 100 men.

Inside of half an hour water was going
into the boiler. All the inside brickwork
was red hot and, although the bottom
sheets of the boiler were not red hot,
they were very hot. The boiler was filled
and 100 pounds of steam pressure were
raised. A few days later I noticed a drop
of water at a rivet where a diagonal brace
was fastened to the bottom sheet. The
boiler was emptied and it was found that
the boiler sheet was slightly cracked at
each side of the boiler where the braces
were riveted to the shell. The braces
were removed, a piece of the shell 8
inches square was cut out at each side
and hard patches were put on, and
through braces were put in when the
others were removed.

The damage was undoubtedly caused
by filling the hot boiler with water, which
caused unequal contraction and left the
boiler in a very dangerous condition.

So far as steam pressure was con-
cerned, there was none formed when the
water was admitted to the boiler, the
sides of which were practically red hot.
Therefore. I do not believe that if would
be possible to cause an explosion by
steam pressure by admitting water into a
red-hot boiler. Of course, if a small
stream of water was penmittcd to run into
a red-hot boiler, and a hot fire was kept
burning under the boiler, an explosion

would certainly take place, but with no
fire and a good stream of cold water
entering, no explosion would occur. How-
ever, I would advise that someone else
try the experiment.

James Ellethorn.
Toronto, Ont.

In reference to H. R. Rockwell's ques-
tions in the issue of September 12, I
would say that letting cold water into a
red-hot boiler will not cause an explo-
sion, providing there is no pressure in
the boiler, but it will rupture the boiler
whetfier the water is hot or cold.

Cutting in two or more boilers with
unequal pressures is not dangerous, but
it is bad practice as it is neither prac-
tical nor economical.

If a battery of boilers are jointly con-
nected and rest on the same foundation
and one boiler explodes, the others are
liable to follow, but they will not go as
high in the air as the first boiler.

A condensing engine or any steam en-
gine should not increase its speed after
the throttle valve is shut tight unless
there is a bypass left open, thereby ad-
mitting steam to the cylinder. A steam
engine is run by steam or air pressure
and it will not increase its speed by its
own momentum, or by perpetual motion,
after the steam pressure is taken off the
piston.

Patrick Molloy.

New York City.

In the September 12 issue, R. H. Rock-
well asks, "Will turning cold water into
a red-hot boiler cause an explosion?"
I do not think so. I once had to replace
54 out of 90 four-inch tubes which were
burned badly, due to lack of water. Al-
though I do not claim that the shell of
this boiler was not injured, it is still
carr>'ing the same pressure as before.
Water was turned in while the boiler was
hot and empty. It has never been proved
that low water or cold water on hot plates
was the direct cause of an explosion,
although it may be the indirect cause of
one.

In regard to the second question, I
cannot see how connecting two boilers
together with the pressures unequal can
cause an explosion providing the nozzles
and header are free from water and or-
dinary care is taken, any more than can
two or more safety valves on a battery of
boilers lifting at the same time or a
couple of engines taking steam from
the same header at the same time. But,
with a slug of water In the pipe, unless
great care Is taken, a hurstcd pipe or
perhaps even a boiler explosion might
be the result.

Referring to the third question, it has
been proved that one boiler in a battery
letting go may carry its m.Ttcs with It, but
the explosions will be so close together
as to merge them info one.

In answer to the fourth question, I
would sav that if an engine is racing

602

and the throttle is closed, the engine will
surely come to a stop unless the throttle
leaks, for the simple reason that a vac-
uum does no work but simply removes
the pressure from one side of the piston
and allows the pressure on the other side
to exert itself.

A. W. Grisvc'Old.

Adams. Mass.

Answering Mr. Rockwell's questions
in the September 12 issue, I will say that
in my opinion turning cold water into a
red-hot boiler will cause an explosion.
The reason is that the plates suddenly
contract to such an extent as to produce
rupture.

Cutting two or more boilers in together
without having the pressure equal will
not be liable to cause an explosion, pro-
vided that ordinary care is used and
the valve is opened slowly. Of course,
it is advisable to have the pressures of
the boilers about the same, but with
due care, and with a boiler capable of
carrying the pressure desired, no explo-
sion should occur.

If one boiler of a battery of several
explodes, it is likely to cause the others
to explode, for the reason that the sudden
rush of steam from the boiler into the
discharge pipe reduces the pressure in
the boiler very rapidly; the reduction of
pressure causes a sudden formation of
a great quantity of steam within the
water, and the heavy mass of water is
thrown toward the opening with great
violence. This strikes the portions of
the boiler near the opening and breaks
it open.

If a condensing engine should be sud-
denly relieved of its load and attain a
dangerous speed and the throttle valve
is closed tight but the condenser con-
tinues to operate and maintain the usual
vacuum, the engine will not increase in
speed, but will eventually stop, providing,
of course, air does not leak into the cyl-
inder, in which case the pressure of the
atmosphere would be on one side of the
piston and a pressure less than that of
an atmosphere on the other.

R. G. Cox.

Milwaukee, Wis.

Efficiency Engineers

I read with interest the letter "Effi-
ciency Engineers," by Alfred Williamson,
in the September 19 issue. As to the
ov.ner being a nontechnical expert, I fail
to see why he need be a technical expert
to know that any material reduction in
operating expenses is being made.

If there are careless or incompetent
firemen or engineers on the job it might
be possible to reduce the operating costs
by careful management, but the plant
would have to he in bad condition which
would allow any man, no matter how
capable, to reduce costs 50 per cent.
Most owners have a fair knowledge of
how rr.uch they pay out for oil, fuel, etc.,

POWER

and I fail to see how the efficiency en-
gineer can accomplish much by making
false statements. Furthermore, I have
never heard of this class of men being
employed where a careful and capable
man was at the helm.

I believe that plant owners are few
and far between who will discharge their
engineers upon the bald statement of
some stranger. The engineer can de-
fend himself if any defense is possible,
for it must be confessed that some en-
gineers have absolutely no claim to such
a name. There are engineers who' call
at plants where no indicator is used, and
who offer to indicate the engine and ex-
plain where changes should be made to
prevent losses. The majority of them
have positions and do the indicating in
spare time or on holidays. They are per-
fectly within their rights. I have heard
of expert firemen who visit owners of
small plants and offer to teach their fire-
men how to fire to get the best results
possible with a certain quantity of fuel.
As a rule they guarantee a saving over
the inexperienced fireman, but I never
heard of one of them taking the other
man's job; there is not enough money in
it to tempt them.

James E. Noble.

Toronto. Can.

Firebrick Arches

I will say for the benefit of H. A.
Jahnke and others that I have not used
iron fire-door linings or mouthpieces in
years.

Firebrick jambs and arches last me
from one to four years, but the cast-iron
pieces were a constant source of trouble.

I have used certain fire-clay blocks for
the firebox part of the furnace, but they
did not do very well for a 10-hour run
as they cracked from the contraction and
expansion. I have no doubt they would
give satisfaction on 24-hour runs.

J. O. Benefiel.

.\nderson. Ind.

Loose Crank Pin

L. A. Fitts' trouble with a centrifugal
oiler on a loose crank pin, as described
in the September 5 issue, seems to me
to be quite a natural occurrence.

With the crank pin loose enough to
turn in the disk and the oiler tightly
screwed to the pin, the pin becomes a
center around which the oiler revolves
in the opposite direction to that in which
the engine is running. If the engine nms
over, this direction must be to the left.
With the oiler turning to the left the
weight on the end must travel faster
than the pin; therefore the inertia of this
weight will tend to cause it to travel
ahead of the pin; this, together with the
jar due to the pin being loose, is suffi-
cient to make it unscrew.

I had t^e same trouble with a small
Corliss engine in a paper mill about a

October 17, 1911

year ago and could find no other ex-
planation.

Ho^J( ARD R. Taylor.

Norwich. Conn.

Safety Stops

In the July 18 issue of Power there
appeared an editorial under the above
caption, which touches the spot exactly.
It brings to my mind an instance which
occurred about a year ago.

I was preparing to take a vacation and
had engaged an engineer (?) to take my
place. He came to the plant the day
before I was to leave, and stayed a whole
hour. While I was telling him where
certain pipes, valves, etc., were to be
found and explaining things in general,
I was very much surprised to hear him
say: "You do not need to go to all this
trouble. I can handle her as good as
anyone."

Upon my return the boss said: "It
took that engineer about one-fourth of
his time getting the engine off the center
and started in the right direction."

The engine is a Hamilton Corliss of
125 horsepower which handles very
easily. As this man claimed to be an
expert who had been doing relief work
in numerous plants, and had been recom-
mended to me, I expected him to be equal
to a job of this size, but it was quite
necessary for me to call him down upon
my return to the plant, when I found the
automatic safety stop weighted on the
light side to hold it in position to save
him the trouble of placing it when he
wished to shut down.

At the present time this "engineer" has
the title of instructor of a local organiza-
tion of engineers, but let us hope for the
safety of those under his instruction, as
well as the general public, that he will
not lead them to believe that it is proper
to incriminate themselves by weighting
an automatic safety stop so that "it will
not auto as it ought to."

Henry A. Stewart.

Toledo. O.

License Laws

In my opinion the license laws are not
as strict as they should be in Ohio. The
law only covers above 30 horsepower
and, as I understand it, is mostly to pro-
tect life and property. If that be the
case, I think we have what I would call
a half law. Take a 30-horsepower boiler
carrying, say, 60 pounds gage pressure
and figure up the energy it contains.
There will be quite enough, I think, to
efface a large patch of landscape near
the boiler.

Engineers, and the public generally,
should insist that laws be passed to cover
all boilers carrying a high pressure. In
some of the cities in this State a water
tender has to have a license and I think
this requirement should be universal.
W. T. Hlrd.

Beliefontaine, O.

October 17. 1911

POWER

603

Issued Weekly by the

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Contents

Power Plant of Curtis Publishing Com-
pany

TransmittlRR Capacities of Pulleys

Iti'ceni K.xploKioDS in ICngland

Purchasing Coal under Specifications. . . .

New Cse for Keep Well Pump

Power Iierivable from Ocean Waves

The Best standard Voltage and Fre-
quency for Three Phase Turl)o Al-
ternators

Induction Motor Troubles

Iilrrct Current Turbo-Generntors Larger
Than '<»<) Kilowatts Capacity

I'siog a Direct Current Maclilni' as a
^lenerator or as a Motor

A Reversal of Polarity

A Producer Gas Canal Tugboat

Practical Letters:

Important Engine Tests. .. .Tempor-
ary Valve Hepair. .. .Loose Bush-
ing Caused Pound .... Experience
with a Cut Cylinder Low Pres-
sure Cylinder Lulirlcator. ... Milling
Bame I'lates. .. .Engineer's Refer-
ence Book .... Steam Ejector ....
Taper Piston Kit .... Shortening
Belts In Damp Wfnthcr. ... Machin-
ery (Jnnrd. . . .Gr.'i|ihlte Reduces Oil
Consnmpllnn .... Stopped the Leak-
ing Tubes. .. .WIr.' In Sight Glass
....Cooling a Hot Crank Pin....
Wedged the Pipe In Place. .. .Tank
ffflge ."O."

Dliicusslon l.ei(ers :

Bleeding Receiver to Ili'nl Feed
Water. . ..Llfllnu' Water In Boilers
....Further Exiierbnces with Man-
agers. . . Heat Triinsmls'slon In Boil-
ers. . . Boiler Room RepBiru. . . .Tur-
bine Accident nt RIverlon. Ill

Sand for Hot Boxes... Mr. Bol-
lard's Diagrams .... To T'revent
Sfandplti'' Freezing. . . .Mr. Rock-
well'. Quoollnns .... Kffleleney En-
gineers ... FIrelirIrk Arehen ....
I^oose Crank Pin . . . .Snfety Slons

.... License Laws "'>'>

Rdltorlals flOS

Thermal and Stnfir TTenrls nnrt fhP Flow

of rient to T tnnltls

The mirlsll" Air Steam Engine

Prime Movers for AuTlIIary Machinery..

Operating Maintenance Expense Accounts
The Manometer an a Lung Tester

The Austin Disaster

Doubtless most of our readers are
familiar with the great destruction
wrought by the failure of a dam at Aus-
tin, Penn., on September thirtieth. Now
that the excitement of the moment has
subsided, the matter may be viewed from
an engineering standpoint, for the adop-
tion of such measures as will make the
recurrence of such a disaster improbable.
Stated briefly, the history of the dam
is as follows: The structure was of re-
inforced concrete, five hundred and fifty
feet long, forty-two feet high, and was
designed to afford a storage capacity for
two hundred million gallons. It rested
on a rock foundation the formation of
which consisted mostly of sandstone
strata interspersed with shale and clay,
and the footing of the dam was carried
into this rock for a depth of only four
feet

It is rumored that the designing en-
gineer wished to carry a cutoff wall
a considerable distance down through
the soft-rock strata to insure against
seepage under the dam, but that the com-
pany would not consent to this, owing to
the additional expense involved.

The dam was completed in December,
!909, and one month later caused con-
siderable alarm by developing several
large cracks and a sliding forward of a
section about ninety feet long. At this
time water was observed coming up
through the ground several feet below
the dam, thus indicating seepage under
ir.

Investigation revealed the fact that the
section which had slid had remained fast
to the rock foundation but that seepage
and the pressure against the dam had
caused one stratum of rock to slide upon
another.

To lower the water and thus partly
relieve the pressure, a small piece was
blown from the top of the dam at one
end, and the cap was also blown from
the drawoff pipe, located at the bottom.
This, however, soon emptied the reser-
voir, so a new cap was put on and the
dam filled again.

Shortly after this the consulting en-
gineer was requested to prepare plans
for strengthening the dam. These plans
were submitted, but apparently no ac-
tion was taken by the company; mean-
while, the dam was continued in daily
use.

On September thirtieth, with but slight

warning nearly the whole foundation slid
forward, breaking the dam into seven
sections, some of which were displaced
from their original positions as much as
twenty-five feet. The water rushing down
the valley practically wiped a whole town
out of existence and resulted in the loss
of over a hundred lives.

From these facts it would appear that
the dam was unsafe from the start, the
necessary precautions having been neg-
lected in order to save expense. For this
both the company and the engineer ap-
pear to be to blame. However, w'hen the
mistake was discovered and the danger
became apparent, the engineer evidently
did all in his power to rectify it, but the
alleged attitude of the company prevented
his recomrnendations from being carried
out.

There is no State supervision over the
construction of dams in Pennsylvania;
in fact, there appears to be none which
amounts to anything in any of the States.
The time has arrived for taking such
measures as will make it impossible for
the policy of private individuals to
jeopardize thq lives of a community. No
doubt such steps will be taken by many
of the States as a result of the present
awakening.

To make such supervision effective,
only the best and most experienced men
should be employed to pass upon the
work. The services of high-class engi-
neers are expensive, but it is better to
spend a few dollars and make the super-
vision adequate. With State inspection
the individual is sure to hide behind the
inspector; consequently inadequate su-
pervision would be worse than none at

The Chii.stie Engine

Our analysis of the thermodynamics
of the Christie air-steam engine in the
September 5 issue has brought many
communications. One of these, of pe-
culiar interest, is from a gentleman who
occupies a prominent position in the en-
gineering world and who says that some
twenty-five years ago, when he was in
the employ of the Acticn-Gcsellschaft
fijr Eiscngiesserei und Maschincnfabrl-
cation, vormals J. T. Frcund & Co., of
Charlottenburg, he was experimenting
upon an engine of exactly the same prin-
ciples. These works had acquired a pat-
ent of a C. Schimniing on an air-steam
engine working exactly the same as

604

POWER

October 17, 1911

Christie's and an engine was built on
the four-stroke cycle principle with the
landem cylinders just like the Waterloo
engine, only with drop valves moved by
cams instead of a Corliss gear.

He is unable to tind any record of or
diagrams from the engine, but the dimen-
sions were approximately one foot cyl-
inder diameter by two feet stroke. The
idea was that by the air being com-
pressed to a high pressure and tempera-
ture before steam was admitted, there
would be practically no initial condensa-
tion, and that during the expansion of
the mixture the steam would give up heat
to the air by condensation and thus in-
crease the work done by the engine and
utilize part of the latent heat otherwise
exhausted through the condenser.

The engine was tested in 1886 or 1887
with a separate boiler connected to it and
proved a complete failure as the steam
consumption was something enormous,
so much so that it exhausted consider-
able quantities of water with the steam
and air mixture. Our correspondent be-
lieves that the air was subsequently
heated by steam before entering the cyl-
inders, but this proved of no advantage
whatever. The engine was dismantled
shortly afterward and the cylinders were
thrown upon the scrap heap.

On another page of this issue will be
found the rejoinder of Mr. Christie to
our criticisms of September 5. This we
are making public out of fairness to him
and in order that the other side of the
question may be heard. .Unfortunately,
however, the reply is taken largely from
the prospectus and reiterates (without
proof) just those assertions which we
refuted in our analysis. Typical of these
is the following statement:

"In the condensing steam engine, great
volumes of cooling water are pumped
through the condenser in an attempt to
create a vacuum and only a partial one
is formed, w-hile in the Christie air-
steam engine a 'perfect' vacuum is ob-
tained without the use of the condenser
or of water for condensing purposes."

Evidently Mr. Christie's conception of
a perfect vacuum does not coincide with
ours.

The only definite information contained
in the rejoinder is that set forth in the
certified report of the test made on
August twenty-sixth. Although these
figures apparently fix the economy of
the engine at first glance, a closer study
of them will fail to satisfy those who
have been following the subject.

To the engineer, the all-important
question is: With a certain power to de-
velop, how many pounds of steam per
hour will be required? A direct answer
to this question is completely sidestepped
by the report of the test. After stating
that the load was furnished by a prony
brake and that runs were made at a
constant brake load, the water rate is
given in terms of indicated horsepower.

With an expanding mixture of steam and
air in the cylinder, it may be possible
to determine from the indicator diagram
just what work is due to the steam; how
accurately we are unable to say. How-
ever, the figures would certainly mean
much more if given in terms of brake
horsepower developed, which would in-
clude the efficiency of compression.

We are led to ask. Why was this not
done when ample opportunity was af-
forded for doing so?

Impos-sible Guarantees

When one is about to purchase a piece
of engineering apparatus he naturally
inquires not only the price but the effi-
ciency. He can buy an engine for fifteen
dollars per horsepower and another for
thirty; but if the more expensive engine
will run upon fifteen pounds of steam
per hour per horsepower while the
cheaper requires thirty, it may be real
economy to pay the higher price. The
seller is therefore asked not only to give
his price but to guarantee performance,
and the purchaser is guided in his selec-
tion by this guarantee of what the ap-
paratus will do.

In the case of large contracts, and es-
pecially upon public work, an acceptance
test is usually made to determine if the
vendor has met his guarantee, but private
purchasers, especially of moderate-sized
installations, are usually content to rest
upon the guarantee.

They are impatient to get the apparatus
into service, not anxious to have their
judgment in its selection demonstrated
at fault; a test is expensive and bother-
some, the guarantee has been a spur to
the builder, and if the apparatus works
satisfactorily and fulfils its purpose they
are quite apt to forego the test and ac-
cept and run the apparatus, the subse-
quent work of which is not apt to be so
closely scrutinized and recorded as to
demonstrate whether the guarantee has
been met or not.

When the guarantee is made in good
faith this course is perhaps the best to
follow. Tests are interesting and valuable,
and the more of them there are made
and published the better we like it. But
it is an expense that a manager might
well spare his record if he were fairly
well satisfied that he was getting what
he was paying for. Unscrupulous, over-
confident or daring manufacturers too
often discount this disposition on the
part of the buyer and guarantee per-
formances which are impossible under
the conditions specified or obtainable
only under the most fortuitous combina-
tion of circumstances.

"How did you dare to make the guar-
antees that you used to make?" was
asked of a manufacturer of, let us say,
feed-water heaters, at a meeting of one
of the leading engineering societies.
"Why, they never tested more than one
in a hundred," was the response, "and

we could afford to take that one out."
These excessive guarantees are some-
times based upon overconfidence or upon
an assumption, unchecked by real engi-
neering ability, that the efficiency ob-
tained under one set of conditions can be
obtained under all. In other cases it is
the result of a cold determination to beat
the other fellow in guarantee if not in
price and to wiggle out of it in the best
way possible if the bluff is called. It
would go hard with some of these engi-
neering adventurers if the German law
were operative here. Under their unfair-
competition legislation anybody publish-
ing a false statement with respect to his
product even in an advertisement is
liable, upon conviction, not only to a
fine but to imprisonment.

Central Station Solicitor Wjll
Not Tell

The majority of engineers look upon
the central station as a menace to them
and to their plant, and upon the central-
station solicitor as a man who is after
their bread and butter.

On the other hand, the central-station
solicitor is out for all of the business he
can get for his company and there is no
reason to suppose that he advances any
argument in getting business which does
not throw weight to his side of the ques-
tion.

When the solicitor is looking over a
proposition he may in some cases see
opportunities where the engineer could
make a saving that would prohibit cen-
tral-station energy being used, because
it would be impossible to meet the iso-
lated-plant production cost. He naturally
does not point out the avenues through
which excessive operation costs leak, but
states to the management that he can
sell it electrical energy at a less cost
than it is making it; he does not say
can make it.

If the engineer does not know where
the leaks are which enable the central-
station energy to put his steam plant
"down and out," he cannot expect that
the representatives of a rival company
are going to take the time and the trouble
to point them out to him. Neither can
he find fault with anybody but himself
when his job has vanished.

The thing for the engineer to do is to
get his plant in such condition that
central-station prices cannot compete
with his cost of operation, to know what
his costs are and to be prepared to argue
the whole question of power costs and to
state his side of the case intelligently and
convincingly when the question is before
the owner. The ability to do this on the
part of the engineer would have pre-
vented the shutting down of many an iso-
lated plant where the management has
found out only by expensive experience
what competent engineers ought to have
told it before the change was made.

October 17, 1911

POWER

605

Steam Pipe Arnviirewent

What is the best way to run the steam

pipe from a boiler to a rock drill at a

distance of 800 to 1000 feet? Should

' there be any difference in the pipe size

and should a separator be used?

A. L. S.
The steam pipe should be one or two
sizes larger than would be required for
the same service at a shorter distance.
It should pitch downward continuously
so as to prevent the pocketing of con-
densation, be covered with the best in-
sulation possible and have a separator
near the drill end.

Boiler and Furnace Efficiency
If a pound of coal gives off 13.000
B.t.u. in combustion, if the boiler utilizes
9000 B.t.u. per pound of coal burned,
and the engine delivers to the band wheel
20 per cent, of the heat value of the
steam, what is the efficiency of the whole
plant?

F. .\. S.
The efficiency of the furnace and boiler
would be

oooo X lOO ,_ o t

^ =: 68 . 1 8 per ccjil.

The efficiency of the boiler plant and en-
gine combined would be
0.6818 • 0.20 -- ion = 13.64 pi-r cent.

Attaching Lubricator to Steam

Pipe

What is the best way to attach a lubri-
cator to a horizontal steam pipe leading
to an engine?

L. H. P.

It makes no difference whether the
lubricator feeds into the top or the side
of the pipe so long as it works properly
itself. The self-feed cylinder-oil lubri-
cator, or any other type, will work equal-
ly well when properly piped, whether on
a vertical steam pipe or on top of or at
the side of a horizontal one, and the en-
trance of the oil to the steam pipe at one
point or another is a matter of indiffer-
ence.

LjOSS in Engine Eriction
Does all the force exerted on a piston
reach the band or flywheel of an engine?
If not, what are the sources of loss?
J. A. F.
If the engine were perfectly fric-
tionless, every foot-pound of energy
exerted against the piston would be
available at the flywheel rim; that is,
the brake horsepower would be equal to
the indicated horsepower. But losses by

Questions .are-

not answered unless

accompanied by the^

name and address of the

inquirer. This page is

for you when stuck-

use it

friction in the mechanism of the ma-
chine reduce the available power to less
than that developed in the cylinder by
about 10 per cent, on the average.

Ejfect of Excessive Clearance
What will be the difference between
the indicator diagrams from an engine
with too much clearance and one with
the right amount?

E. E. C.
An indicator diagram from an engine
cylinder having excessive clearance will
show a higher terminal pressure than one
with a reasonable amount for the same
point of cutoff. The cutoff will appear
to be the same in both instances, but
there will be a difference in the expan-
sion line, and also in the compression
curve, as with the added clearance the
compression curve will not rise so high.

Economy of I ^sing Steam
Expansively

Why is it more economical to cut off
high-pressure steam early in the stroke
than to use steam of a lower pressure
for the full length of the stroke?

E. S. E.

When steam is cut off early in the
stroke, a large' part of the force moving
the piston is derived from the expansion
of the steam admitted up to the point of
cutoff. If used full stroke there is no
expansion and a cylinderful of steam
at the lower pressure would weigh more
than the partial cylinderful necessary
for the same mean effective pressure at
a higher initial pressure. A steam cyl-
inder of 4 cubic feet capacity taking
steam at 100 pounds pressure and cut-
ling off at one-fourth stroke would, neg-
lecting clearance and condensation, use
I cubic foot of steam per stroke and
have a mean effective pressure of about
53 pounds per square inch. The weight
of the steam used would be 0.26 pound.
If 4 cubic feet of steam at a pressure of
53 pounds were used its weight would
be 0.54 pound, or more than twice as
much as would be needed for the higher
pressure used expansively.

Inertia Governor Weight

What will be the effect of adding to
the weight on the long arm of a Rites
governor?

W. G. W.

It will diminish its sensitiveness, and
the engine will not regulate as closely as
before.

Discharge through 24-inch
Pipe

What would be the rate of flow through
a 24-inch cast-iron pipe 3000 feet long
with four 90-degree elbows and a head
of 2 feet?

E. H. G.

The flow of water through a clean cast-
iron pipe is expressed by the formula

Imp

where

K = Velocity in feet per second;
L — Length of pipe in feet;
H = Head in feet;
D = Diameter in feet.
If the pipe has long-radius bends —
that is, of a radius not less than five
diameters of the pipe — the flow will not
be affected materially. However, a short
90-degree elbow on a 24-inch pipe will
be equivalent to adding about 125 feet
of straight pipe; hence the four elbows
are equivalent to 500 feet.
Substituting in the formula

V

=^°\ni

S.soo

= 1 .69 jcct per second
The cross-section of the pipe is 3. 1 416
square feet, and there are approximately
7'^ gallons in a cubic foot. Therefore
the discharge per hour is
1.69 X 3.1416 \ 3600 X 7.5 = 144,(XH)
gallons.

Nitrate of Silver Test for Salt

How is nitrate of silver used to de-
tect the presence of salt in the discharge
from a surface condenser?

N. S. T.

Take a few crystals of silver nitrate,
moisten them with one or two drops of
chemically pure nitric acid and dissolve
in half a glass of fresh water. Into a
glassful of the water to be tested put
three or four drops of the nitric acid and
then an equal number of drops of the
silver and water solution. The presence
of salt is indicated by a whitish, cloudy
appearance of the water. •

606

POWER

October 17, 1911

Thermal and Static llcatlsaiid

the Flow of Heat and

Liquids

By F. E. Matthews

In following out the comparison of
thermal and static heads and the flow of
heat and liquids, it should be remembered
that coal is simply the vehicle for carry-
ing heat radiated from the sun lo the
earth ages ago. The absorption of solar
heat produced a chemical process by
which carbon dioxide from the atmos-
phere was broken up in the plant cells
of the vast prehistoric vegetable growths
and formed fixed carbon in the plant
tissues and free oxygen exhaled into the
air. In the process of combustion of
coal, free oxygen from the air again
combines with the fixed carbon of the
plant, forming carbon dioxide, and the
long imprisoned solar heat is liberated.
Not only is solar heat of former ages,
stored up in coal, now made to do use-
ful work through the evaporation of
water in boilers, but the solar heat of
the present day evaporates the moisture
which, precipitated from the rain clouds,
collects to form the cataracts that turn
the turbines. In raising the vapor from
the surface of the earth to the clouds
a certain amount of energy is expended.
In passing the steam from the boiler to
the engine there is also an expenditure
of energy.

When the two forms of vapor have
leached their respective destinations they
possess considerable potential energy
and when pressed into service 'n ap-
propriately designed machines will be
able to perform useful work. When •'he
atmospheric vapor has been divested of a
sufficient amount of its latent heat it con-
denses into rain and were there a suit-
able machine at hand a part of the foot-
pounds of work developed by the falling
rain could be utilized.

Enormous amounts of power are stored
in the torrents of water precipitated on
the great watersheds that feed the North-
ern lakes and finally flow down the
Niagara river, a part to turn the wheels
of industry and a part to dissipate the
acquired energy on its way to the ocean.

In the accompanying figure is shown a
conventionalized machine for utiliiiing a
part of the energy in a small stream of
water diverted from the Niagara river
above the falls. While theoretically a
modern vertical turbine might have been
employed in this analogy, for simplicity
of detail and similarity of comparison a

bucket conveyer is shown. Water from
the duct leading from the river is dis-
charged into the buckets near the top of
a sprocket wheel. The weight of the
descending water in the upper chain of
buckets turns the lower shaft carrying a
second chain of buckets so arranged as
to elevate the water accumulating in the
shaft below the level of the river, and
discharge it into a trough near the point
of discharge of the upper chain at such
a hight that it can flow away by gravity
into the river.

The power available in any machine is
the product of the force applied and the
space through which it acts. In the pres-
ent example the distance between the
point of charging and that of discharg-
ing the buckets is about 60 feet, so that
every thousand pounds of water dis-
charged per minute will have exerted
60,000 foot-pounds, every 33,000 of
which is equivalent to a horsepower of
work, and every 778 of which is equiva-
lent to 1 B.t.u. of heat (60,000 foot-
pounds per minute equals 1.82 horse-
power, or 77.1 B.t.u.). In this example
iv is obvious that the higher the point at
which the weight can be received and
the lower the point at which it can be
discharged, the more power will be de-
veloped.

The amount of power to be expended
in raising the water from the shaft de-
pends not only on the number of pounds
of water to be raised 'n a given time,
but also on the number of feet through
which it is to be raised. If the water is
running into the shaft at different levels
it is obvious that less power will be
required if it is collected and conducted
into the conveyer at about the levels at
which it enters than if it were all al-
lowed to flow to the bottom of the shaft.
If the hight of the point of discharge
be more than just sufficient to allow the
water to flow away to the river, work will
be unnecessarily expended. Similarly, if
the point of discharge of the water from
the upper buckets is higher than neces-
sary to enable the water to flow away
freely, loss of power will result. Since

the water discharged from both sets of
buckets must all flow into the river, the
points of discharge may be on the same
level, as shown, or at different levels,
providing both levels are above that of
the river.

The analogy of lifting and discharging
water and of absorbing and rejecting heat
is now apparent. The source of the
water available for producing power is
60 feet above the point at which the
water is discharged from the buckets,
representing the heat energy of steam
available at a temperature of 370 degrees
Fahrenheit. This steam may be expanded
to the lowest pressure, or the heat may
be allowed to flow to the lowest tempera-
ture, at which it can still flow away into
the river of condenser water. If this
temperature is 126 degrees Fahrenheit
the corresponding pressure will be 26
inches vacuum.

This falling of temperature resulting
from the conversion of heat into work,
in the steam engine shown en the left
in the accompanying figure, is repre-
sented by the steam-indicator diagram
shown on the right, temperatures at any
point of which are approximately indi-
cated by the thermometer.

The water to be removed from the pit
represents heat to be removed from the
lower levels of temperature found in
cold-storage compartments. This heat
has to be elevated almost to the same
level at which heat from the engine is
exhausted, because of the fact that the
most satisfactory disposition of the heat
from both sources is to let it flow into
the same river of condenser water. The
lower the point of discharge the more
power will be available in driving the
chain per pound of water, and the less
power will be required to raise a given
quantity of water in the driven chain.
The lower the temperature of the con-
denser water the more power will be de-
veloped in the driving steam engine per
pound of steam expended and the less
the power required to raise a given quan-
tity of heat in the driven refrigerating
machine. In other words, the efficiency
of the driving machine depends directly
on the difference in head of the water
entering and leaving the buckets, just as
that of a steam engine depends on the
difference in temperature between the
steam in the boiler and that in the con-
denser.

Similarly the efficiency of the driven
machine increases directly as the differ-
ence in head between the water leaving

October 17. 1911

POWER

607

and entering the buckets decreases, just
as that of a compression refrigerating ma-
chine increases as the difference in tem-
perature between the gas in the con-
denser and that in the cooler decreases.
Since the temperature of steam at the
lowest point to which it is practical to
expand it is considerably above that of
the refrigerating medium liquefying at
the lowest temperature that available
cooling water will allow, it is found
economical in practice to first permit the
heat from the refrigerating medium to
few into the cooling water, after which
its thermal level, or temperature, even
after being raised by heat from the re-
frigerating-machine condensers, will still
be sufficiently low to allow heat from the
steam-engine condensers to flow into it.
The diagram illustrates this to the ex-
tent of showing that the point of dis-
charge of the water from the driving con-
veyer is slightly above that of the driven

through the walls of the shaft into the
driven conveyer. The operation of the
compressor of the refrigerating machine
shown on the left is also represented in
the compressor-indicator diagram shown
on the right, hights in feet, temperatures
in degrees, and corresponding pressures
in pounds, being represented on the three
scales also shown at the right.

In some cases in which a single com-
paratively high cold-storage temperature
is to be maintained, it is not necessary
in the analogy to keep the water pumped
down to the bottom of the shaft. If coil
£=, for example, is shut off, there being
no demand for the temperature of — ^5
degrees Fahrenheit shown on the ther-
mometer scale opposite level A, and only
coil El is in ser\'ice, producing a tempera-
ture of about 24 degrees Fahrenheit, cor-
responding to level By the logical method
of operation would be to let the back
pressure of the evaporating refrigerant

ciently below that level to allow the out-
side water to flow by gravity into the
conveyer buckets at that level.

The foregoing conditions; namely, of
producing a single temperature, un-
fortunately has to do only with the most
economical conditions of operation of
which the system is capable. It more
frequently happens that two or more
v.idely different temperatures, 26 degrees,
— 5 degrees, etc., such as would be
produced by coils E,, £., etc., are re-
quired. If the two refrigerating loads
from coils £i and £: happen to be so
proportioned that the vapor coming from
each can be compressed separately in
one cylinder of a two-cylinder machine,
or one end of a double-acting compressor,
the operation of the plant may be put on
the most economical basis by dividing
the suction lines to gain this end.

To complete the analogy it is neces-
sary to remember that in the operation

Diagram Illustrating Similarity of Flow of Heat and Water

conveyer. The cooling water containing
the heat from the steam condenser is
shown in the diagram flowing away with
the water from the driving conveyer and
that from the refrigerating-machine con-
denser with the water from the driven
conveyer.

The two sets of expansion coils, E,
and £;. located the one above the other,
represent the different thermal levels or
temperatures at which the heat is ab-
sorbed in two cold-stnraec rooms. The
different temperatures at which these
two storage rooms are to be maintained
is also represented by the hight of the
•pouts which deliver the water seeping

rise until its corresponding temperatures
have risen from — 5 to 24 degrees Fah-
renheit, or if these be the actual cold-
storage temperatures required, until a
temperature is reached sufficiently below
the required cold-storage temperature to
provide the thermal head necessary to
produce the flow of heat from the lir of
the refrigerated compartment to the evap-
orating refrigerant in the expansion coil.
This increase in hack pressure, from 10
to about .Vi pounds, as indicated on the
scale at the right hand of the accom-
panying fleure. corresponds to a rise in
wafer level in the shaft from 10 feet
above the bottom to 3fi feet, or just suffl-

ol the driving as well as the driven chain
of buckets there are losses by friction in
the bearings as in a steam engine and
compressor; losses in capacity due to
imperfect filling of the buckets corre-
sponding to imperfect cylinder filling in
a compressor; losses due to leaks in the
buckets all along the line corresponding
to leaks by valves and pistons of the
steam engine and compressor, cylinder
condensation and any other means by
which a unit of heat can escape contribut-
ing its share to the general cause of de-
veloping power to produce refrigeration.
In the case of the best steam-power
plants, all but about 1."^ per cent, of the

608

POWER

October 17, 1911

lieat "leaks away" without performing
any useful work. In the average steam
plant all but about 6 or 8 per cent, is
lost, so that it is of the utmost import-
ance that this small remaining percentage
of heat be utilized to the best possible
advantage in the refrigerating machine.

The next most important detail to be
considered after that of keeping the
compressor in good mechanical rep.iir, is
to see that the condenser pressure or
point of discharge of the water is as low
as possible and that the evaporating or
back pressure is as high as possible, or
that the buckets pick up the water at as
high a level as possible. Assuming that
the point of discharge of the water be
100 feet above the bottom of the shaft,
100 foot-pounds of work must be e.\-
pended in a theoretically perfect ma-
chine to elevate a single pound of Afater.
At the efficiency of the average ammonia
compressor, from 25 to 35 additional
foot-pounds would have to be supplied
to look after leaks and other losses. If
all the water enters the shaft at A, a
point only 65 feet below the point of dis-
charge or 35 feet above the bottom of
the shaft, and means of directing it into
the buckets at this level be devised, only
65 foot-pounds in a theoretically perfect
machine, or only from 81 to 88 foot-
pounds in a machine of the efficiency of
an ammonia compressor, need be ex-
pended to do the same amount of work.

Assuming, similarly, that the refriger-
ating machine, represented by the chain
of buckets, discharges the heat at a tem-
perature 100 degrees Fahrenheit above
that of the colder refrigerator coil corre-
sponding to the bottom of the shaft, which
temperature, for the sake of similarity,
may be taken at 0 degree Fahrenheit,
the horsepower per ton of refrigeration
would be 1.2194.* Interpolating to find
the temperature from which heat equiva-
lent to a ton of refrigeration can be
raised by the expenditure of half that
amount of power, or 0.6097 horsepower
per ton, a cooler temperature of approxi-
mately 42' J degrees Fahrenheit is ob-
tained.

If a refrigerating plant is so operated
that the heat which enters the refriger-
ator at such a temperature that it can be
absorbed by a refrigerant at 42 'j de-
grees Fahrenheit has to be absorbed at
0 degree Fahrenheit, in other words, if
the plant is operated at 16 pounds back
pressure when it could be operated at
61 pounds, one-half the power will be as
needlessly expended as would be the case
if the water entering the shaft 50 feet
above the bottom were allowed to flow
to the bottom, requiring the buckets to
lift it 100 feet instead of 50 feet.

The example just cited need be none
the less significant because of the un-
usual back pressure of 61 pounds gage.

F.xcept for selecting temperatures to
agree with the feet-head of water already
mentioned in the analogy, lower tem-
peratures might just as well have been
considered, for example:

The horsepower required per ton of re-
frigeration when the back pressure is 4
pounds gage, corresponding to a tem-
perature of — 20 degrees Fahrenheit,
and the same head pressure of 200
pounds gage, corresponding to a tem-
perature of 100 degrees Fahrenheit, is
1.6090. Again interpolating the table it
may be found that half this power per
ton would be expended when the back
pressure is 38 pounds, corresponding to
a refrigerator temperature of 24.4 de-
grees Fahrenheit.

For convenience in comparison the
foregoing figures are shown in the ac-
companying table.

POWER TO PRODUCE REFRIGERATION

Refrigerator

Condenser

Horsepower

Pres-
sure,
Lb. Gage

Teraper-

ture,
Deg. F.

Pres-
sure,
Lb.
Gage

Tem-
pera-
ture,
Deg.
F.

Per Ton

Refri-
geration

Per

Cent .

16
61

0
42i

200

100

1.2194
0.6097

100
.")0

4

:fs

—20
24.4

200

100

1.6090
0 , 8045

100

•See tnhle of horsepowei' per tim of refrlj;-
elation — Seliniidt, "Compendium of Mecluin-
ieal Refrigeration." page 440.

While from the foregoing it would
seem inexcusable to operate a refrigerat-
ing plant at a lower back pressure than
is actually required to produce the de-
sired temperatures, yet it is probable
that not over 10 per cent, of the plants
in commercial operation today are op-
erating under anywhere near the ad-
vantageous conditions with regard to
back pressure that they should.

The problem becomes less easy of so-
lution as the number of different tem-
peratures increases. Again following out
the chain-pump analogy, let an extreme
case be assumed in which 90 per cent,
of the water flows into the shaft at a
hight of 50 feet from the bottom, and
the remaining 10 per cent, at the bottom.
The theoretical amount of energy re-
quired to raise one ton, or 2000 pounds,
of water from the levels at which it
runs in woufd be
(2000 X 0.90 X 50) -f (2000 x 0.10 X

100) = 110,000 foot-pounds
If all the water be allowed to flow to the
bottom of the shaft it will take

2000 X 100 = 200,000 foot-pounds
or 81.8 per cent, more power than by
the former method. If 90 per cent, of a
ton of refrigerating duty be performed
at 24.4 degrees Fahrenheit, and 38
pounds back pressure and the remaining
10 per cent, of the ton at — 20 degrees
Fahrenheit and 4 pounds back pressure,
the actual amount of power required will
be

(0.90 X 0.8045) + (0.10 X 1.609) =
0.8849 horsepower

but if the expansion coils for producing
both temperatures are connected into a
common suction line so that all of the
work of refrigeration has to be done at
— 20 degrees Fahrenheit and 4 pounds
back pressure, the power required will
be 1.6087, or, as in the case of the water,
81.8 per cent, more than by the former
method.

To avoid expending this additional
amount of power the same solution pre-
sents itself in both cases in question.
Two separate machines may be installed,
one to perform the more difficult work
of raising the lesser amounts of water or
heat through the greater distance, and
the other to perform the less difficult
work of raising the larger amount of
v/ater or heat through the lesser dis-
tance. Either two compression or two
absorption machines may be detailed to
the two duties, or, on account of the
higher efficiency of the absorption over
the compression machine when operating
on very low temperatures, the work may
be allotted to one compression and one
absorption machine; or a unit may be
employed of the proper capacity for
raising all of the water or heat from the
higher level, while a second unit is em-
ployed to raise the lesser amounts ot
water or heat from the lower level to
the middle level where the other machine
begins to operate.

If in refrigerating plants equipped with
a single double-acting compressor, or two
single-acting compressors, the high- and
iow-temperature loads are so propor-
tioned that one end of a double-acting
compressor can be made to handle the
high-temperature load and the other the
low, or in the case of two single-acting
compressors, the load may be similarly
divided between the two compressors, the
maximum efficiency of operation may be
obtained.

Still another way out of the difficulty,
and one which avoids many complications
arising in the preceding case, is to allow
the buckets to run to the lower level
and pick up such load as there may be,
whether large or small, after which the
additional load is taken on at the higher
level. By this method the load is picked
up at whatever level it happens to oc-
cupy.

When applied to the compressor of a
refrigerating machine, the method is to
admit the low pressure feas returning
from the coldest expansion coils directly
into the cylinder. When a sufficient part
of the stroke has been completed to
provide for the low-pressure gas, a sec-
ondary suction valve is opened and the
higher-pressure gas from the higher-tem-
perature expansion coils is introduced.
The low-pressure gas is prevented from
returning through its suction line by the
closing of the low-pressure suction
valves or simply a check valve in the
low-pressure line.

October 17, 1911

POWER

609

The Christie Air Steam Engine

Your article of September 5 on the
Christie air-steam engine was grossly
unjust and especially to Prof. E. J.
Christie. He is not an officer nor a di-
rector in the company and so far as he is
concerned the publication under the Iowa
law is a libel.

Professor Christie has taught thermo-
dynamics in three different colleges and
a university. His first announcement of
'the theory over two years ago was un-
derstood and published by some of the
best informed men in this country, among
them H. B. MacFarland, M. M. E., and
Frank Richards, author of "Richards on
Compressed Air." You have been grossly
misinformed and we trust that you are
willing to ai^ us in giving the truth to
the public.

We recognize that the engine must
stand on its merits. It takes time and
money to make tests and we are doing
the best we can and will furnish data
as we get them.

The engine is especially designed for
the work in hand and can be operated
with a 28-, 30-, 32-, 34- or a 36-inch
stroke. This changes the clearance. The
engine has four speeds: 80, 100, 125 and
150 revolutions per minute. It is built
for steam pressures up to 200 pounds
per square inch and this should be borne
in mind in computing its maximum horse-
power.

The steam is the source of power. The
air itself neither produces nor absorbs
power, except to the losses due to fric-
tion and radiation in handling it. By
noting Fig. I it is at once plain that
while air is expanding (with steam) in
one end of the cylinder, a like volume
of air is being compressed in the op-
posite end. These two air forces are
thus balanced, subject to losses to fric-
tion and radiation. While air is enter-
ing one cylinder head with the pressure
of the atmosphere forcing it in, the ex-
haust is being pushed out against the
back pressure of the atmosphere. These
two forces are likewise balanced and
thus the exhaust is expelled at the mere
cost of friction and radiation. In the
regular noncondensing steam engine the
piston is pushed forward by the steam
and the cylinder is left full of steam
which must be pushed out against the
back pressure of the atmosphere. This
requires 14.7 pounds of steam pressure
per square inch of piston area up to the
point of closing the exhaust valve. A
piston with an area of 100 square inches
requires a total of 1470 pounds of pres-
sure to expel the exhaust. In the or-
dinary steam engine, steam balances the
external pressure of the atmosphere,
while in the Christie air-steam Corliss
engine the air balances the external pres-
sure of the atmosphere.

By John T. Christie *

Mr. Christie replies to
our criticism of his engine
in the September 5 issue.
The reply is taken largely
frovt the original prospec-
tus and contains mostly
generalities. For further
comment see the editorial
pages of this isstie.

♦Secrotar.v of the Cliristio Engine Comp.Tuy.

The Steam from the boiler rushes in
and does the work of pushing the piston
forward to the point of cutoff C, Fig. 2,
and a mixture is thus formed at or very
nearly the same temperature as the
steam. If we compress the air into a
clearance space of 1 cubic foot and the

Steam Valve
Open
[~| First Stroke

at 100.6 pounds pressure and at nearly
328 degrees temperature. In the mixture
the pressures will be in the ratio of the
volumes or two-thirds air pressure and
one-third steam pressure. The steam in
the mixture will have an approximate
pressure of ZZ pounds and the same tem-
perature as the mixture, 328 degrees.
The temperature of saturated steam at
33 pounds is 255.8 degrees. The steam
in the mixture cannot condense until it
falls to less than this temperature. The
difference between the two temperatures
is 73.2 degrees, which represents the
degrees of superheat produced by thus
mixing steam and compressed air. Hence
the engine has the benefit of initially
superheated steam.

In the condensing steam engine, great
volumes of cooling water are pumped
through the condenser in an attempt to
create a vacuum and only a partial one
is formed, while in the Christie air-
steam Corliss engine a perfect vacuum
is obtained, without the use of the con-

First Stroke

Exhausting 14.7 lb.

Steam Vahe Open
Second Stroke {~f

Exhnustina 147 lb

■ Valve Open

[~| Second Stroke

::^3=r

Exhaus t Valve Open

Compressing Hi

3 L

^

Exhaust Valve Open
_Q Third Stroke

13 cr

AirValveOpei
Steam Valve Open

Y~| Third Stroke r~|

TZT
Air Valve Open

Exhaust Valve Open

Fir,. I. Diagram Illustrating Cycle op Operation

pressure is 100.6 pounds and the tem-
perature the same as saturated steam,
328 degrees Fahrenheit, and if the steam
enters at the same pressure and tem-
perature and pushes the piston forward
until the total volume of steam and com-
pressed air is increased .SO per cent., we
will then have l^> cubic feet of mixture

denser or of water for condensing pur-
poses.

The compressed air recxpands on a
higher line of pressure than it costs to
compress it because of its increased tem-
perature when mixed with the steam. If
at the point of beginning compression
the air has a temperature of 125 degrees

610

POWER

October 17, 1911

and if at the end of the expansion stroke
the steam has a pressure of 7.3 pounds,
then both the air and the steam will
have a temperature of 179 degrees (see
Fig. 2, in which O B represents the com-
pression line and B M the expansion line
of air. The shaded space represents
the relative pressure of the steam in the
mixture). This added work of the air is
l)roduced from the heat borrowed from
the steam. The specific heat of steam
being twice that of air, if a volume of
steam is lost in this way, approximately
two of air are returned. For this reason
the steam must enter the cylinder at the
same or a higher temperature than the
compressed air. If the heat of the com-
pressed air is transferred to steam, the

^Steam Valve Sfeam Valve
d.B, C D(^

'' (Q)K L lero Pressure Line W '0
pb«w -Exhaust Valve £■

■Exhaust Valve Exhaust Valve

Fig. 2. Showing Expansion of Air and
Steam in Cylinder

total volume is shrunk, instead of being
increased.

It will be noted that the air, when re-
expanding with the steam, has a higher
temperaf^re and consequently a higher
pressure than during compression, per-
forming more work in reexpanding than
it cost to compress it. To perform this
extra work, heat is transferred from the
steam over to the air. The direct work
done by the steam in the mixture, to-
gether with the extra work done by the
air with the heat borrowed from the
steam, is exactly equivalent to the work
which the steam would perform if it
were expanded alone to the same final
absolute temperature as that of the mix-
ture. The extra work performed by the
air in the mixture is exactly equivalent
to the extra work the steam would per-
form if expanded alone to the same final
temperature. The total work from the
heat of the steam in the mixture thus is
net, subject of course to the losses suf-
fered to friction and radiation.

The net result is that the work of the
steam has been condensed into a shorter
stroke with a higher terminal net pres-
sure than if it had been expanded alone
in a perfect vacuum to the same ter-
minal temperature.

It must be borne in mind in ex-
panding steam from a high pressure to
a low terminal pressure in a single cyl-
inder that the cylinder volume must be
approximately the same as the total vol-
ume in the high- and low-pressure cyl-
inders of a compound-condensing engine.
If the reader will consult "Peabody's
Steam and Entropy Tables" he can find
the expansion work of steam (after cut-
off) to any final pressure, together with
its final volume. In the Christie air-

steam engine cylinder, this final volume
will not be so great because a part of it
will have been condensed in reheating
and reexpanding the air.

In the work so far we have demon-
strated that the highest pressure at which
saturated steam can be worked with
economy is at or near 110 pounds from
the boiler. Above this pressure the tem-
perature of the compressed air rises more
rapidly than the temperatures for corre-
sponding pressures of saturated steam,
in which case the compressed air is
cooled by the steam, so that the air can-
not return in work what it cost to com-
press it. In going to higher pressures,
superheated steam must be employed. To
get the best results even with super-
heated steam it would seem that the
temperature of the steam should be but
little higher than that of the compressed
air.

Engine Tested

Waterloo, la., August 26, 1911.
To Whom It May Concern:

This is to certify that on Saturday,
August 26, 1911, a five-hour economy
test run was made on the Christie air-
steam Corliss engine at the Christie En-
gine Company's plant in North Water-
loo, la. The engine was loaded by means
of a prony brake. The indicated horse-
power of the engine was determined by
using an improved American-Thompson
indicator. Readings were taken in each
cylinder every 15 minutes.

The length of stroke in each of the
two cvlinders was 32 inches and the

Fig. 3. Indicator Diagram

diameter of each cylinder 14 inches. The
engine was run at a constant speed of
104 revolutions per minute. The steam
pressure in the boiler was maintained at
from 115 to 125 pounds. The water used
by the boiler, which furnished steam
for this engine only, was very accurately
weighed. The run being of five hours'
duration was sufficiently long to furnish
data for quite accurate results.

The results obtained are as follows:
The temperature of the exhaust, meas-
ured not over 12 inches from the cyl-
inder, remained constant at 184 degrees
Fahrenheit. Referring to the steam tables,
this temperature corresponds with an ab-
solute pressure of 8.19 pounds. The
temperature of exhaust of noncondensing
steam engines at the same distance from
the cylinder would be 212 degrees Fah-
renheit, with atmospheric pressure at
14.7 pounds.

The indicator cards showed an average
of 66.6 indicated horsepower. In secur-
ing this result a constant and fixed load
was maintained on the brake. The water
used by the engine per hour was 1750
pounds or 26.35 pounds per hour per in-
dicated horsepower.

John T. Christie.

Prime Movers for Auxiliary

Machinerj-

By W. J. a. London

The increasing use of the small steam
turbine for driving the auxiliaries in large
power plants raises the interesting ques-
tion as to why this is taking place. There
are at the present time three types of
prime movers for auxiliary machinery,
the electric motor, the reciprocating en-
gine and the small steam turbine. The
main factor to be considered in auxiliary
machinery is the question of reliability;
the efficiency, owing to the small percent-
age of power absorbed, being a secondary
consideration. It must be borne in mind
that station costs are quite a factor, as
modern plant managers do not contem-
plate skilled labor for attendance, so that
the question resolves itself into the con-
sideration of reliability, economy, mini-
mum amount of attendance necessary and
elimination of accidents.

While the motor drive is often the most
efficient, it may not be if the auxiliaries
are run noncondensing and there is
capacity in the heaters to use all of the
exhaust steam. The electrically driven
auxiliary is clean and can be installed in
a simple manner; the wiring is more
flexible than steam and exhaust piping;
it is easy to start and stop.

But condenser pits are not the driest
places on earth. The dangers to the at-
tendants from electrical leakage are often
serious, and should the main current
fail for any reason, all the auxiliaries
are put out of commission.

When steam-driven auxiliaries are
used, they take the motive power direct
from the boilers which are generally ie
last units to fail in a power station, thus
eliminating the possibility of failure of
any intermediate apparatus.

Steam-driven auxiliaries may be
divided into two classes: reciprocating
engines and steam turbines. The re-
ciprocating engine naturally requires
more attention than a motor, and cylin-
der lubrication is necessary; it results in
a discharge of oil to the heater or to the
condenser and therefore to the boiler.
The wear which takes place in reciprocat-
ing engines is naturally greater than in
an electric motor, and the renewals of
parts is more frequent.

The growing tendency to use superheat
is a factor and this is responsible for
the supplanting of many reciprocating
engines by small turbines. The recipro-
cating engine is in some cases superior

October 17. 1911

P O \X' E R

611

to the steam turbine in steam economy,
but there are many cases where the re-
verse is true.

With regard to motor drive and recip-
rocating engines, there is the simplicity
of the motor as compared with the re-
ciprocating engine, but the turbine very
nearly approaches the simplicity of
the motor. There is the steam piping
the same as with the engine, but the dan-
gers of insufficiently warming up and of
forgetting to open pet cocks is eliminated
in the case of the turbine. A steam tur-
bine properly designed for the work is
not Injured by a slug of. water as is the
case with a reciprocating engine. There-
fore in this respect it requires less atten-
tion than an engine and ver>' little more
than a motor. The question of oiling is
almost identical with that of the motor,
so that the regular attendance is prac-
tically the same in both cases.

The simplicity of construction of the
modern small turbine is in itself indic-
ative of its fitness for work where re-
liability, minimum of attendance, main-
tenance and repairs are important fac-
tors. Some engineers express the view
that there will be no excuse for having
anything but turbines for driving power-
plant auxiliaries in the near future.

Opcratiiii^ MainteiKince Ex-
pense Accounts

At the annual convention of the Ameri-
can Electric Railway Accountants' and
Engineering Associations, held at Atlantic

19)0 Report
Arcoi*NT .Nfi. 30. — Maintenance of Power
Plant Eqiipmen-t:
.'JOOI .Maintenance of engines, turl>ines anil

pnmps
.■J002 Maintenance of lx>ilers, inclu'lini; fur-
naces, stokere and setting-^.

Maintenance of pipe system, includ-
ing .ateam, exhausi, oil. air and ga-s
pipes, all fillings, valves and cover-
ings.

Maintenance of auxiliaries, including
economizers, condensers, cooling
lowers, ash and coal elevators, other
elevators, etc.

300,'} Maintt-nanc<- of electric plant.

City, N. J., October 9 to 13, the sub-
committee on the review of the 1910 re-
port on operating-maintenance expense
accounts considered it advisable to elabo-
rate the subdivisions as there seemed to
be a lack of knowledge as to their flex-
ibility, and there were possibilities of fur-
ther subdivisions of the subaccounts of
the 1910 report.

The suggested changes for the mainte-
nance of power-plant and substation
equipment are included in the accom-
pany table.

The Manometer as a Lung

Tester

By John French

There were four of us seated around
the big fireplace in which a blazing
pyramid of pine logs was roaring. After
a silence of several minutes, interrupted
only by the crackling of the flames.
Newton Steers, who was purchasing
agent for a big engineering firm, burst
out with, "Say, fellows, I have a prob-
lem for you,"

"Fire ahead 1" came the chorus,
"Today a man came in trying to sell
me some gages, and just as he was leav-
ing, minus a couple of cigars and with an
order tucked away in his pocket, he
asked: 'How many pounds pressure do
you think you could maintain with your
lungs?' 'You have me there,' I said,
filling my lungs and trying to blow,"

I'.m .-iugeestions

MUD, Mi^oilaneous, including such il<'ms as
^team gag«*s. sl<*am anfl RaI<T
m<'lers. fe#*cl. water conlrollr-rs.
damiKT regulators and similar de-
vice*.

•OVKT No. ,11. MAISTKNASrE OP SlB-

■TATIOS EqIIPMKVT:

.1101 Mainlenanci' of electric plant

■3102 Misrellaneoiixiiubiitstlon malnlenanc>v

3001-.\
.300 1-B
30O2-.\

30O2-B
3002-<:
,3002-1)
None.

3l>04-.\
.3(KII-B
.300 l-C
.3001-1)
:iOOI-E
30(H-F
,30(1 l-r,
3<H1.".-A
30I).".-IJ

300."i-C

aoo.j-t)

300.-,-E

3O0.-P-H
.3o:).-,-I

.30IKI-B

Maintenance of engines.
>laintenance of turbines.
>Iaintei)ance of furnaces, including

grates and crate supports.
Maintenance of stoker^.
Maintenance of tioiler settings.
Misci-nuneoiK l.oil-r r.-pairs.

nliti.ince
nienanoe

Mainlt-nanre i
Maintenanc.' •
.Mainlenanrt' <
>iaintenan<'<-
Mise.llaneoM-

iili'tia

sysii-m-
Matnti-nauce of ■

tiusli;»rs. oil -"
Maint<'n;inc»' of

charging oiitlil
W iring
M.scrtanmus
rr.»ne-. hoists
.Miso'llani-oiis

)f pumps.

»f economizers.

if condensers.

if healers.

if a^li anil coni machinery.

aiixiliar.v re|inirs.
( ilirecl-current Eeneratoni.
if alternating-current gen-
comiM-n.sators.
>f ixciters.
rif rotary converhTs.
if transformers and cooling

nf switchboards, including

^uiirlii-s and insirumi-nts.

"torage li-.tlerii*s and

■le<'lrical items.

etc

•team instruments

.3101-,\

M.iii

I. u i;

3I0I-B

Man

li-n.ii

siom;

Mall
III

li'ti.ii

3101-1)

Main

tenar

rli

dinif

3101-E

Wiri

3101 -K

\}

3 102- A

(> .

3102-B

A ■

<• iif iran"former« and cooling

n- of sHilrhlioanl. including
ml -»itrh''s and inslnimpnlK.
(I- of storagi* ballerie«, In-
rliarging oiitnts

"Came kind of natural, didn't it?"
interrupted Russell Herder,

Newt continued without paying any
attention to the last remark, "'About
ten pounds, I guess.' "

"Gee," came from Jack Harrington,
who up to this time had maintained a
discreet silence, "I bet I could blow over
fifteen,"

"No, you couldn't!" cried Russ, "You
would be lucky if you could make it
eight."

"About twelve pounds is my style,"

Test Your Lung Capacity

I observed, as I blew out a big cloud
of smoke as if to back up my statements.

"We all agree so nicely. I tell you
what let us do," said Newt; "tomorrow
is Saturday so we will be free in the
afternoon. Let us go out to the 'lab' and
each take a blow on one of Russ' iner-
cury manometers; then the man that
made the nearest guess to our average
blow will be invited to a 'blowout' by
the rest."

"That's a go!" we all cried.

"You'll need one over three feet high,"
said Jack, "or we will blow the mercury
all out of it."

"Never you mind. Jack, old boy," re-
plied Russ, "I have a manometer that
will balance all you can blow, and more
too."

To make a long story short, the next
day we all had a try on the manometer
and that evening a bang-up dinner for
which one of us did not have to dig
down in his pockets.

If any of the readers of Power are
interested to know who got the dinner,
let thein tr>' and see how many pounds
they can blow. It won't be far from
what we did.

The total enrolment of students at the
University of Illinois on October 1 at
Champaign- Urbana was 3020. Of this
number, the College of Engineering is
credited with 120(), distributed as fol-
lows: Architecture and architectural en-
gineering, ,3<>f5; civil engineering. 251;
electrical engineering. 2StO; mechanical
engineering, 27,5; mining engineering. 21 ;
municipal and sanitary engineering, 27;
railway engineering, 36.

612

POWER

October 17, 1911

•^-Lis_ '■-^iirf-,^. ^_ ^^

Jeffrey Smgle Roll Coal
Crusher

The Jeffrey single-roll coal crusher,
Fig. 1, is designed to reduce run-of-mine
coal to 94-'nch size and under in one
operation, and can be set for any size
product from 8 inches to '4 inch. The
crusher is self-feeding and can be lo-
cated directly beneath the receiving hop-
per or bin, no other feeding device be-
ing necessary. It is strongly built to
withstand extra-hard continual service

Fic. 1. Single Roll Coal Crusher

and is equipped with a safety device
against destruction due to foreign sub-
stances getting into the rolls.

The crusher consists of a heavy cast-
iron frame in which are mounted a
crusher roll and a breaker plate. The
breaker plate is hinged at its inner edge
and is held in position by a pair of ad-
justing rods at the lower end by means
of which the clear opening between the
breaker-plate shoe and the surface of
the roll can be adjusted to give any size

Fig. 2. Crushing Roll and Tketh

of coal required. As the concave breaker
plate acts in conjunction with the roll, it
makes a form of maw with a ver>' small
angle; hence the machine will grip a
very large lump of coal and reduce it to
a size that will pass through the opening
between the roll and the plate.

The crusher roll is shown in Fig. 2. The
toothed segments are bolted to the con-

vex surface of the drum so as to com-
pletely cover it. The frame and hopper
are so arranged that by removing the
steel guard plates access may be had to
the bolt and the segments removed and
replaced by new ones without disturbing
either the roll or the hopper. The long
hooked teeth not only act as feeders, but
they grip the large pieces and break them
up to a size which will readily enter the
maw of the machine. Narrow gaps in
the shoe of the breaker plate enable the
long teeth to pass without dragging over-
sized pieces with them. By making the
smaller teeth on the segments of the
proper shape as shown, a proper reduc-
tion is made with a minimum amount of
slack coal.

The toothed segments are usually made

pins inserted in holes in the arms of
the pulleys. When any undue straia
comes on the machine from any cause,
these wooden pins shear off and the roll
stops while the pulley keeps on revolving.
This forms a ver>' efficient safety stop.
After the cause of the trouble is removed,
new wooden pins put the machine in
operative condition. A pair of heavy
springs are placed on the tension rod,
but the springs do not move under or-
dinary working conditions. When, how-
ever, undue pressure comes on the
breaker plate, the springs act as a cushion,
giving way slightly, taking up the inertia
of the parts and allowing time for the
pins to shear without breaking more im-
portant elements in the machine. This
coal crusher is manufactured by the
Jeffrey Manufacturing Company, Colum-
bus, 6.

Goulds High Pressure Triplex
Plunger Pump

The Goulds Manufacturing Company,
Seneca Falls, N. Y., has just placed a
new high-pressure single-acting triplex
power pump on the market. This pump
is in general use in mines, waterworks

Goulds High-pressure Triplex Plunger Pu.mp

of very hard iron, each segment being
in a single piece. When the work is ex-
ceptionally severe the long teeth are
made of cast steel and are inserted in the
body of the segment or the segments are
made entirely of manganese steel.

The driving pulley is not keyed to the
shaft, but is mounted on a separate hub
which is driven through a set of wooden

and with hydraulic elevators, fire-protec-
tion systems, hydraulic presses, oil-pipe
lines, etc. It is designed for pressures
ranging from 215 to 1500 pounds. As
shown by the illustration, the new pump
has only one gear and pinion, which are
located between the standards.

Placing the gearing between the stand-
ards necessarily lengthened one side of

October 17. 1911

POWER

613

the pump somewhat and increased the
distance between the two valve boxes on
that side. Instead of lengthening the
pipe connection between the valve boxes
on one set and making each set of a dif-
ferent shape, a distance piece is put in
as shown. In this way the three sets
of valve boxes are kept identical in form
and are interchangeable.

Richardson Electric Coal
Scale

/ The weighing mechanism of this new
electric coal scale, shown in Fig. 1, con-
sists merely of a cast-iron hopper sus-
pended from one arm of a cast-steel
weighing beam. The other arm supports
an inclosed conically capped weighing
receptacle for cast-iron weights. The
actuating power is that of gravity supple-
mented by electricity. The weighing is

Fic. I. Richardson Electric Coal Scale

performed on a closed electric circuit and
the discharge is the result of the open-
ing of the circuit. The operation of the
scale is as follows:

It requires but a I/16-horscpower
motor to feed the coal down the vibrat-
ing chute by means of the vibrator,
m'hich weighs about 2 ounces, and is all
that is needed to give the chute the nec-
essary vibrating movement. As the vibrat-
ing chute driven by the motor fails
to vibrate until a speed of about SflO
revolutions per minute is reached, the
motor does not receive its load until it
has attained a proper speed.

Presuming the weights for the prede-

termined quantity it is desired to weigh
are in their receptacle, the weight-box
end of the beam is depressed; the
main electric switch of the scale is in,
and the motor is started. This operates
an eccentric at the opposite end of the
chute, which causes the chute placed di-
rectly over the weigh hopper to vibrate.

Discharqe Unor
remains Open u
•Material Tallsr.

Fig. 2. Outline of Electric Scale anii
Parts

This chute is set at such an angle that
when the vibration ceases the material
lying in it ceases to flow.

The chute continues to vibrate until
the weighing hopper descends to the bal-
anced position, which action operates a
switch in the box immediately behind
the motor. When the switch breaks the
motor stops; therefore the vibration stops

also, and the flow of material into the
weighing hopper ceases instantly.

Swinging on the bottom of the weigh-
ing hopper is a valve which controls the
discharge of material from the scale.
While the hopper is receiving its load,
this valve, or cast-iron door, is held
closed by a magnet at the back. Sim-
ultaneously with the cutting out of the
motor the magnet is also cut out and
the scale discharges its load into the
spout below. The weight of coal is au-
tomatically registered by a mechanical
counter that is attached to the weighing
hopper.

The machine is not stopped or other-
wise interfered with by foreign matter or
large lumps within reasonable limits. It
has no actual cutoff gate or valve to be-
come choked or stopped in its action.
The cutoff is caused simply by relying
upon the angle of piling of the material.

In Fig. 2 is a diagrammatic sketch
showing an outline of the electric scale
and its various parts, also the path of the
electric current. The application of the
scale to a battery of boilers is shown in
Fig. 3.

This electric scale is manufactured by
the Richardson Scale Company, 5 Park
row. New York City.

Invjncihle Steel Asbestos
Gaskets

A new gasket for use on water-tube
boilers has been put on the market by
Everybody's Packing Company, Bourse
building, Philadelphia, Penn.

It is made of a heavy asbestos cord
which is covered by a thin seamless steel
jacket. A feature of this gasket is that

Fir.. 3. APPLICAtmN OP THE SCALE TO THE BoiLER

614

POWER

October 17, 1911

it does not stick on thie plates or header.
It can easily be removed with a cold
chisel, and no further cIcaninR of the
plates is required, thereby eliminating
labor.

These gaskets are now being made for
Babcock & Wilcox. Heine, Edge Moor,
Keeler, Geary and Murray boilers.

New Buffalo Exhaust Fan

The Buffalo Forge Company, Buffalo,
N. Y., has perfected a slow-speed multi-
blade exhaust fan which is said to have
proved exceptionally economical in power
consumption. The high efficiency of this
fan is attributed to the design of the fan
wheel, which is illustrated in Fig. 1. The
slow speed reduces the power consump-

ExiiAusTER Blast Fan Wheel

tion, minimizes the wear and the cost of
upkeep and it lengthens the life of the
fan.

The applications of the fan are almost
as numerous as those of standard de-
sign, as sawdust, shavings, spent tanbark,

Fic. 2. Double Reversible Steel-plate
Fan

grain, wool, cotton, dust, smoke, gases,
etc., are handled.

These fans are made' single or double
in sizes from 30 up to 80 inches in diam-
eter, and for pressures from 1 to 6
ounces. They are made with reversible
housing. A double fan is shown in Fig. 2.

Cloth Pinions

Cloth pinions which have been designed
to reduce noise and increase their life
are manufactured by the General Electric
Company, Schenectady, N. Y.

The blanks from which the pinions are
cut consist of a filler of cotton or similar
material confined, at a pressure of sev-
eral tons to the square inch, between

Huhn Flexible Metallic
Packing

This packing consists of packing rings,
garter springs, steam rings and a case
which contains the combined rings and
garter springs.

Each white-metal alloy packing ring
is made hollow and ia two segments.

Types of Cloth Pinions

steel side plates, the whole structure be-
ing held together by means of rivets, or,
in case of very small pinions, by threaded
sleeves. After the teeth are cut the
cloth filler is impregnated with oil. Cloth
pinions are said to be entirely impervious
to moisture, unaffected by changes in at-
mospheric conditions and absolutely ver-
min proof. Three kinds of cloth pinions
are shown in the accompanying illustra-
tion.

The teeth are sufficiently elastic to al-
low the meshing teeth to bear evenly
across the full width of the face, thereby

The hollow portion is filled with graphite
under hydraulic pressure, and the graph-
ite is fed through small holes and lubri-
cates the rods.

The halves of each ring are drawn to-
gether by means of garter springs which
are inserted in the grooves of the pack-
ing ring, as shown.

The steam ring is made of either
brass or bronze and in two or more
segments, varying with the diameter of
the rod. They are of sufficient diameter
to engage the annular grooves which are
made in the cage.

Huhn Metallic Packing Ring

enabling the combination to absorb
shocks. The pinions are self-lubricatinj ,
and have a wide range of applicatioi .
Ordinarily, the pinions furnished con-
stitute the smaller members of the gear
train, but practically any size and form
of gear can be obtained, including a gear
of large diameter consisting of a spider
with cloth-filled rim.

The joints of the segments are stag-
gered with those of the packing rings
and are maintained in position by lock
pins. Details of the packing are shown
in the accompanying illustration.

This packing is manufactured by the
American Huhn Metallic Packing Com-
pany, 416 East Thirty-second street. New
York City.

October 17. 1911

P O VC' F. R

Evening Courses at Lewis
Institute

The schedule of continuation courses
at the Lewis Institute, of Chicago, which
is being given evenings and Saturdays
and began October 9, includes engineer-
ing, chemistry, physics, mathematics,
drawing and languages.

These courses are arranged so that
they can be taken independently or in
connection with regular college work or
in series to form a logical development
of the subject, and are designed to af-
ford those who are employed an oppor-
tunity to continue their vocational studies.
Of the total enrollment of 3200 during
the past season over 1800 were enrolled
in the continuation classes.

The engineering series includes engi-
neering principles, electrical measure-
ments, direct-current machinery, rotary
converters in substation work, alternat-
ing-current principles, transformers and
transmission lines, alternating-current
motors and generators, steam-engine test-
ing, internal-combustion engine, struc-
tural-steel design and concrete reinforced.
The mechanic arts series includes me-
chanical and architectural drawing, ma-
chinery drawing and design, lathe and
milling-machine work, tool and die and
pattern making, foundry and forge work.
The mathematics series is especially
arranged for engineers and includes
algebra, geometry, trigonometry, analytics
and calculus. Work is also offered in
English, Latin, German, French and
Italian.

International Association for
Testing Materials

At the fifth congress of the Interna-
tional Association for Testing Materials,
held at Copenhagen in September, 1909,
it was voted, on the invitation extended
bv the American Society for Testing Ma-
terials, to hold its sixth congress in this
country in 1912. It will be under the .
patronage of President Taft and will take
place during the week beginning Septem-
ber 2, 1912. at the Engineering Societies
building, New York City.

One of the most important functions
of this association is the establishment
of standard specifications for materials
used in manufacture and construction;
improve the methods of testing; investi-
gate properties which are capable of in-
dustrial usefulness; unify the methods
of tcstinp throughout the world, and to
introduce standard international reception
specifications for materials with a view
to facilitating international trade. Twenty-
eight countries arc represented in the
association's membership.

Under the stirring inlluence of Ameri-
can industrial conditions the coming con-
Rress promises, through its interchange
of experience r.nd investigations, to act

with stimulating effect on these various
subjects.

.As these specifications are of great
value to engineers and others who are
engaged in the purchase and use of the
raw materials of the trades, H. F. J.
Porter, secretary of the organizing com-
mittee, urges that all concerned join the
association in order to attend the con-
gress and aid in establishing these speci-
fications.

Full information can be had by ad-
dressing H. F. J. Porter, secretary, 1
Madison avenue. New York City.

Educational Program, Chicago
Branch, L O. E.

For its monthly meetings from October
until May, the Chicago branch of the
Institute of Operating Engineers has
planned an interesting educational pro-
gram of lectures, the first of which,
"Some. Future Possibilities of Steam
Power," by Osborn Monnett, was de-
livered on October 3.

The following lectures will be given
during the season: November 7, "Steam
Boilers," by J. P. Fleming; December 5,
"Steam Piping," by W. L. Fergus; Janu-
ary 2, "Reciprocating Engine Practice,"
by F. J. Davidson; "Uses of Steam Tur-
bines under Special Conditions," by
Edwin D. Dreyfus; "Gas Producers," by
H. F. Smith; "Oil Engines," by J. C.
Miller; "Power-plant Economics," by
G. F. Gebhardt.

High Record for Continuous
Pumping

In his report to the general superin-
tendent of the Cincinnati waterworks,
S. G. Pollard, superintendent of opera-
tion, says that the average pumping duty
at the main pumping station, for nine
months, based on plunger displacement,
was the equivalent of 144,869,000 pounds
of water raised 1 foot high for each 100
pounds of coal.

This record stands alone for con-
tinuous pumping-station economy, and
Mr. Pollard says that, so far as he is
aware, it has never been approached by
any pumping station in the world,

Hiram Hawes' B'iler Laws
By H. E. Hopkins

It!i E'>l''llni: fnnnv for mo to iin.v.
I!nt n t>imlf<l lilliT |mvril lli>r wn.v
for nllrmplln' »onn- rf-illr'loiiii l«n»
On thi-r pnrt of nnnrr'lilc Illrnm llnw™.
Ilo'd ro|trO'U'ntp<l ii« (|iillo n spoil
An" tlior foll<<i fo Iiomo Iiml liooril lilm loll
Thiit In thor lloiiao of liln nnllvo HIato
TlioroVI l>o nomn i1oln*« ' Hiil I rnTlnto
Thor nolno HI inmlo nnx oiroodin' llclil.
An' llior folk"" linrk Iiomo «•«« i1l«eti"lo(t qiiHo.
Knr Ihov n roir fo 1,1m : "8oo lioro. Ill llnn-on.
Yo nin'r <lon<' nolhin' lo holp tlior obiko V
Tlion III (■onrohrd 'rounrt tor "omo vo-tilrlr
Tlinfd liRiit htm out of IhU I.in1 ploVlo.
Ill" wll" eot KorVIn". Ilkowl.o hi. 1nw< :
"I hov II" bI,o..i.i III: •••II. I.'llor lawii''^

\ l/ller had bust in his balliwicli —

In fac'. hiul soared to ther sk.v so quick

That it sent to glor.v yoims Zeke Stiuthers

.\n' more oi- less injured thirteen others.

•'.liminy crickets !'* sez old Hi Hawes."

"Ill draft a bill to perhlbit them flaws

From sending b'ilers inter ther skies,

So. wldders and orphens. wipe yer eyes I"

One line day HI riz from his chair

.\n* to his colieaKues did declare :

" This is act one-seventy-eight

Which is intended to regulate

.\n' run all IVilers by set rules

Itettern laid down by. books an" schools.

."^omo State rules may hev more eultur".

Hut these laws hev more ne plux ultra.

.\ll b"llers must use Iher B.t.u.

Whether they liev ther tube or flue ;

This is ther way to measure ther heat

.\n" for most b"ilers can"t be beat.

"l"here"s Centigrade and Fahrenheit

That some folks sez are out o" sight,

Hut these strange names might make confusion

In oTir new laws is my conclusion.

liilers that are allowed to rust

Soon get et up an" quickly bust ;

Ther same appertains to tulw an" bolt

.\s this glial destroyer takes its holt.

'When b"IIers show signs of r.p.m.
Its time to move away from Ihem."
"rhis Is a starter for Section 1 —
■'I'will slop so many risks bein" run.
Si'ctlon -' prescrilwR thet 'ther shell
Shall be made of steel an' riveted well.'
Most bllers are best when kep" indoors ;
I'lien Iher engineer kin do bis chores
.\n' lie piMlecled from rain an" sun.
Hllers Is queer, when all's said an' done.
I've hoerd of one of the wooden type —
Hut Iher time for them is not quite ripe—
Its trouble wuz not (hot she got rusted;
She swelled up so ihel ther dum thing busted.
Scr-tlon ;t : 'You must reduce ther pounds
When a h'iler grunts an' makes sirnnge sounds.'
Sumo things should lie said alioul b.p..
riior mcnuin" of which aln"t clear to m-.
It might 111" used as a sep"rale clause
An' later put In Iher rog'lar laws.
An lionir'lilo member wr. : 'High proof.'
Kul Mint means speerlts. I hold aloof
From things that favor ther demon mm.
An' I rlz my voice In protest high--."

.Iiisl when III llawos hod reached Ihls p'lnt
Thor memlHTs" no.ses got out of J"lnt,
\n' from them memliero. "wols" an' "drys."
I'nmo words Ihal eaiiseil quite some surprise:
"Wo ain't no use for yer b'iler laws !
Hhel up! Set down. Mister Illram Unwos I"
No man with sorh ro dir'inus Idoes
rould over hop.' hl« deesfrlC lo please.
An' now In lil« pineo .el. .lonadah .Ihiite.
A» for Illram. nolmdv glros a hoot:
lie slay, lo homo, nmlndlne' hl» cnwR
An* miTo. hl««rlf In nil inore row..

616

POWER

October 17, 1911

Moments with the J^.^dltor

In some direct, illuminat-
ino; words about the Hill
publications, the Old j\Ian
the other day said:

"As a matter of fact,
these papers of ours are not
newspapers or magazines at
all. They are engineering
tools to work with."

The truth could noL be better stated, and
ill the case of Power it has a particular
.application. For Power that statement
might be translated into:

" Power is a personal jackscrew to shove
upward with."

Power is built to furnish just that per-
sonal upward jackscrew • shove, once you
take hold of the handle and turn. As we
see it, it wouldn't be worth publishing other-
wise.

If you, for instance, happen to be a man
to whom the phrase "shove upward" isn't
chock full of significance and stimulus. Power
isn't worth while to you. You oughtn't to
subscribe. For the man who does that cheats
us into believing we have one more unit to
add to our argument when we talk to adver-
tisers about what Power can do.

Here's the reason:

The only thing that keeps a paper like
Power from being run at a money loss is the
advertising.

And firms buy space in Power to advertise
what they have to sell because it is represented
to them that Power is subscribed for and
read by men who are precisely the sort that,
bv their live-wire interest in and up-to-the-
ninute knowledge of everything hitting the
power plant are going to get after the Boss,
get a grip on him, swing him over to the
action they are convinced is right, whenever
"Which to buy?" "What to do?" turns
up in that department.

Take coal. You see a coal ad. in Power
that gets a hold on you. You have that coal
tested out. It "lives up to the ad." Then,

by persistent hammering on
the Purchasing Agent, and
through him on the Boss,
you make the next coal con-
tract follow the lead of that
test, and the new coal, in the
course of a month, proves a
money saver of ten big letters.

Suppose you are going to be disregarded
in the • plant any longer? Xot when the
calender reads 19 ii. For you have worked
yourself up longside, or even a little beyond
perhaps, the heads of some other depart-
ments— that have been making a showier
splurge about "scientific efficiency."

With Power as a jackscrew, you have
shoved yourself up.

In that you are a typical Power man.

So, when we tell the big advertisers that
the character of Power readers is what is
stated above, we represent truth. There's
a pull from somewhere that brings those
firms orders — and they know it's from you.
You can play your last dollar they wouldn't
keep on advertising in Power if they didn't
feel the pull and didn't know where it came
from.

If you weren't a Pow er man, in this jack-
screw-up sense, you wouldn't be reading
Power, so there's no use talking about
"happen to be'' at all.

But if ever one of the other kind got hold
of Power, by mistake, we would say to him
this:

Cut out Power.

Spend the time and money on Sunday
supplements or the picture magazines.

Tliev don't care icho reads them.

Power does care — most emphatically.

And knows that its readers believe in this
latter-dav advertising, read it and buv from
it.

Pin your faith in the advertised article,
and you can't go far wrong.

Vol. 34

NEW YORK, OCTOBER 24, 1Q11

No. 17

Do You Need an Engineer? Do You Want a Position?

Power has been dealing with the engineers of
the country for a third of a century'. It knows them
not only as a class, but out of its constituency many
individuals have come to our especial notice through
long association, intelligent interest evinced by corres-
pondence with the editors, contributions to our columns
and by especial achievement.

We have seen men grow from the time when
their awakening interest led them to come to us with
the questions which arose when they just began to
look for the "why?" of things, until they are in charge
of large installations and octnipy the highest plane in
their vocation.

\Vc know men who arc modestly folkiwing out a
daily round in small positions whose attainments
qualify them for better things.

We know good men who are temporarily out
of employment.

We know mediocre men for those who do
not care to pay for better.

If you are thinking of making a change, if your
engineer has left or is going to leave it, it will be a
pleasure for us to undertake to put you into com-
munication with a suitable man, to tell you what we
know about him and leave you to make your own
arrangements.

That we may do this intelligently it is neces-
sary that we should know the size and character of
your plant; the degree of authority and responsibility
with which the man is to be invested; the opporHinity
for advancement and for making a record; the salary
or wages which you are willing to pay, the hours
during which the plant is run, etc.

This may be given to us with the fullest confidence
that it will not be divulged or misused in such a way
as to causi- you any annoyance.

Power has recommended many men to situations
and in few, if any, cases have they failed to make
good. An increasing number of employers are coming
to us for such recommendations and we like to be
used in this way.

While we enjoy the acquaintance and are in-
formed as to the capabilities and aspirations of many
of our readers, we realize that there are very many
equally entitled to consideration and whom we .should
be equally glad to help of whom we have no jjer-
sonal knowledge.

Powi:r will best serve its purpose when it is
most useful to its readers ahd we shall be glad if we
can make it more useful by helping them to better
positions.

If you are out of a ]X)sition, if you feel that vou
are capable of greater things than your present situa-
tion affords or jiromises, write and let us see if we
can do anything for you. Tell us what your, experi-
ence has been, what sorts and sizes of plants you
have handled, whether you have been in resjionsible
charge or simply standing watch. What sort of a
record have you made? Where are you willing to
go? What is the minimum salary you will consider?
To whom can you refer for testitnoni.ils as to char-
acter and ability?

Vou can send us this information with the fullest
confidence that it will not become known outside of
our olTice. Vou need not worry ff)r fear your ])resenl
employer will learn that you are lr>-ing to imjirove
your conflition Keep in touch with us, keep us in
mind of you and kce)! your record with us complete
so that when we receive an inquiry for a man of your
tyiK- we shall find your name and the best argument
you can ])resent for your claim for consideration
in our file.

P O \X' E R

October 24, 1911

A Coney Island Power Plant

Of the thousands of visitors to Coney
Island during a season, but few realize
that there is but one large isolated-power
plant in operation on the island. This
plant is at Feltman's, which is said to
be the largest resort of its kind in the
world, and provides for the wants of
25,000 people in one day in the restaurant
alone; and as many as 36,000 frank-
furters and rolls have been sold in a day
during the past season.

This plant is in charge of James A.
Westberg and the thousands of engineer-
ing friends who have visited this resort
have doubtless wondered how the plant
can be kept in operation when competi-
tion by the central station is so strong. In
fact, most of the current supplied for
illuminating and power purposes at Coney
Island is taken from the central station.
It is said upon good authority, however,
that next season several of the plants
which were discarded for central-station
service will be put back into operation,
and that in one or more instances new
power plants will be constructed.

After the visitor has passed through

By Warren O. Rogers

One of the fezv isolated
pmver plants at Coney Is-
land which has not been
supplanted by the central
station.

Tivo of the engines are
1 9 years old and one has been
in service for 34 years, but
electrical e^iergy is delivered
to the switchboard for less
than 2 cents per kiloivatt-
hoiir.

during the open season. They are direct
connected to a 100-kilowatt and a 30-
kilowatt direct-current generator respec-
tively. Generally 115 volts is carried on
the switchboard, which is comprised of
three Vermont marble panels upon which

this it is necessary that the fresh meats
and other perishable provisions shall be
kept at suitable temperatures; therefore
various cold-storage rooms have been
built convenient to the kitchens. A 30-
ton brine Frick refrigerating machine is
located in the engine room and supplies
the refrigerant for the entire establish-
ment. There is also one 15-ton machine,
N.hich was the original installation, but
this unit is now held in reserve. They are
shown in Fig. 2. The machines are con-
nected with a triple-pipe cooling system
and after the brine has passed through
the 38 ice boxes it is used before return-
ing to the cooler to freeze the ice in the
ice cans.

There are two 6j4x6-inch brine pumps.
In case one should give out, the other
will take care of the brine and prevent
the system freezing.

The construction of the buildings at
Coney Island are of wood and other in-
flammable material and therefore fire pro-
tection independent of that supplied by
the town is necessary. To provide for
this, a 16 and 9 by 12-inch fire pump is

Fic, I. Partial View of the Engine Roo.m at Feltman's

the main entrance of Feltman's and
down by the various gardens, if he will
turn to the left through a passageway he
will see the steam plant which illuminates
this resort.

In the engine room there are two Ifix
16-inch Ames, and one 12xI4-inch Arm-
ington-Sims engines. Both of the Ames
engines have been in service 19 year's
and the small engine has been in service
for 34 years. All are used every night

the switches, recording instruments, etc.,
are mounted. There are five distributing
boards located at different points through-
out the establishment so that the several
gardens can be cut in or out as desired
without notifying the engine room. The
plant frequently runs with a load of 300
kilowatts, most of the current being used
for illuminating purposes. A view of
the engine room is shown in Fig. 1.

Naturally, in such an establishment as

kept under steam pressure both day and
night during the season. There is also
a 10 and 6 by 12-inch pump which can
be used for fire protection, but it fur-
nishes water for laundry, kitchen supply,
etc., at other times. Water can be put
on any part of the house in 39 seconds,
so thoroughly are the employees drilled.
There are 8000 feet of 2'. .-inch hose and
14 monitors on the roof, each capable
of delivering 250 gallons of water per

October 24: 1911

P O \(' E R

619

minute. This enables the fire fighters to
do excellent work, and in the case of a
recent Are in a neighboring building, they
had their hose playing on it some time
before the arrival of the fire department
upon the scene.

ton. An average of 8'_. tons of coal per
day of 24 hours is burned. The cost of
putting electrical energy on the switch-
board is less than 2 cents per kilowatt-
hour, which cost includes wages, supplies,
repairs and depreciation of the plant.

Fic. 2. New 30-ton Ammonia Compressor

All cooking throughout the establish-
ment is done by steam with the excep-
tion of roasting and broiling. There are
seven kitchens to be supplied besides the
department for steaming clams, lobsters,
etc.

In the boiler room. Fig. 3, there are two

Although the engines in this plant have
been in service over 19 years, and one
of them over 34 years, electrical energy
is produced at a lower rate than it can
be purchased from the central station,
which not only speaks well for the ability
of the chief engineer, but also emphasizes

new and the low cost of operation is due
to the management of Chief Engineer
Westberg. The plant is well worth look-
ing over by any visitor who happens to
be in the vicinity.

Passing of Anotlier \'eteran
By John S. Leese

The Brownsfield mills, of Manchester,
England, were built in 1820 and the mo-
tive power for the machinery was fur-
nished by a single-cylinder condensing
double-acting throttle-governed beam en-
gine made by the then famous firm of en-
gineers, Peel, Williams & Peel. Until a
few months ago this old engine kept the
wheels turning in the mills, and if excel-
lence of material, sound construction and
minimum wear are any criteria it would
have done so for many years to come.
One of the chief reasons for scrapping
the engine and replacing it by electric
motors was the discontinuance of wood-
working machinery by one of the tenants
in the mill, the chips fomierly having
been used as fuel under the boilers. An-
other reason was the small load factor
due to the different working hours of the
various tenants.

The bore and stroke of the engine
were 38 inches and 7 feet 6 inches re-
spectively, and the speed was 18 revolu-
tions per minute. The length of the beam
was 22 feet 6 inches and it was 3 feet
deep in the center across the bearings.
The hight of the cylinder casting was
9 feet from flange to flange and the valve
chamber, in which worked an old type
"D" slide valve, was cast integral with it.
The cast-iron connecting rod was 21 feet
long and the crank pin was 5 inches in

Fir,. ^. RoiLFR<; HwiNT. CoMBiNin CAPAriTV of S20 HnRcrpoirFR

lOO-horsepower. two 80-horscpnwer and
one 200-horscpower return-tubular boil-
ers; there i? also a 2fiO-horsepower
water-tube boiler. These boilers are hand
fired and pea coal is used at a cost

the fact that if an engineer has the cap-
abilities he will have no trouble in pro-
ducinc current at a lower rate than it
can be purchased from outside sources.
The plant is kept in a very neat and clean

delivery to the boiler room of S4.20 per condition, the machines look almost like

diameter by 7'' inches lone. This was
keyed into the 8' -inch thick oval-shaped
crank web. which, in turn, operated the
cast-iron crank shaft which had a maxi-
mum machined diameter of 10 inches and
a length of 8 feet. The shaft was only

620

POWER

October 24, 1911

machined at the journals and flywheel,
eccentric and spur-wheel necks. The
flywheel was 24 feet in diameter and
weighed about 14 tons. It was seg-
mentally built up of eight sections, the
spokes being tapered from 4>{>xl2 inches,
rectangular section, at the boss end to
3J4\9'A inches at the rim end.

Keyed to the crank shaft, outside the
flywheel and inside the outboard bearing,
was a spui wheel driving a wheel on a
second-motion shaft. On this second-
motion shaft was mounted a bevel wheel
meshing with another bevel wheel on an
upright shaft; this, in turn, extended to
the top of the mill, each of the seven
stories deriving its power from line shafts
driven by bevel gears off the vertical
shaft. The diameter of the vertical shaft
was reduced step by step as it ascended
from floor to floor.

In the early , sixties, one wing of the
mills, which are L-shaped in plan, was
gutted by fire and all the shafting in that
portion was destroyed, but, up to the time
of being discontinued, the whole of the
original gearing and shafting in the old
part of the mills was in operation, with
the exception of the old jaw couplings
in one of the weaving sheds which were
replaced by muff couplings.

The valve of the old packed "D"
slide type and the original hemp-packed
piston, more recently fitted with a Lan-

caster spiral-spring type ring, were un-
changed throughout the life of the en-
gine. All bearings and journals were

1

' m

i

Partial View of Engine

plain unbushed iron to iron and were

lubricated with ordinary heavy engine oil.

The engine was fed with steam at 60

pounds pressure by an 8-inch steam pipe

from two 28x7-foot patent two-flue Gallo-
way boilers which were installed in 1879.
These boilers replaced the original
wagon-type boilers which were installed
with the engine in 1820.

A 27-inch vacuum was maintained to
the last by the original jet condenser.
The feed and condensing water v.'ere
obtained from a branch of the Rochdale
canal, which runs outside the mills. This
branch gets all the dirt and scum from
the main canal washed into it by the
boats so that the builders suffered rather
badly from foaming and scaling. The
chimney was built into the middle of the
circular staircase leading to the several
stories of the mills and on the top of
the stack was a ring-shaped tank or
cistern which received the overflow from
the boiler-feed pump. Pipes from this
tank to the different stories of the build-
ing conveyed water for fire purposes and
to the boilers in case of emergency or
accident to the feed pump.

The photograph of the engine shows
the old cross-arm type of governor with
its vertical operating rod reaching over-
head, the cast-iron connecting rod, the
cylinder, part of the valve rods and one
of the columns in the background. It
will also be noticed that the crank pin is
cottered to the web in the old style with
the cotter pin right through both pin and
web.

Value of Engine Room Inspection

The "trouble man" who visits many
plants finds in the majority of cases that
if the operator in charge had used a
system of inspection, he could have
avoided trouble. Outside of steamship
operation and large power houses, where
discipline is enforced, there are hundreds
of plants in charge of men who never
had the proper training and who do not
see the necessity of systematic inspection.

What better name than "scientific man-
agement in the engine room" could be
applied to a system whereby the operator
upon shutting down for the day looks
over his engine and examines by sight
and touch every part. He feels all the
bearings to see if they are cool; tries
every bolt and nut to see if they are se-
cure, and then lifts the oil guards to be
sure that the parts out of sight are tight
and secure; moreover, he makes certain
that all drips are open, that the oil flows
freely in the pipes and channels and that
the lubricator is shut off with the oil. He
then examines the boiler before leaving
to make sure that the fire is properly
banked, the damper closed, the ashpit
doors closed and the fire doors open;
that the proper amount of water is in the
gage glass and that the valves to the
water glass are closed for the night. The
feed pump should also receive attention.

In the morning, the same man will en-
ter the boiler room and open the gage-

By Hubert E. Collins

A tJwrough inspection of
the entire plant by the engi-
neer when going on watch
will often avert serious
trouble, besides fixing the
responsibility should any-
thing wrong be discovered.
Several instances are cited
to show the advisability of
such a practice.

glass cocks, note the water level and then
start the fire; and while steam is rising
he will examine the engine again to note
that it is in the same condition in which
he left it the night before. He will also
take sufficient time to warm the engine
before throwing on the full load.

Some operators contend that after
working long hours in hot engine rooms
they should leave as soon as they can
stop the engine and see that the fires are
banked. The writer still contends that,
in the long run. the operator will lose
more time by this method than by a
proper system of inspection. The op-
erator often terminates his employment
by lack of this same system.

Again, when the plant is in operation, it
is well to regularly, once a day, test the
safety valve by raising it from the seat to
see that it is not stuck. Many explosions
could be prevented by this practice.

.Also, a log sheet plays an important
part in this system, and even though sim-
ple, it is an aid; one in which the steam
pressure is noted hourly, and the daily
consumption of fuel and oil is recorded.
If the steam pressure is notated hourly
it, if nothing more, insures the fire room
being visited just that often if the read-
ings are taken conscientiously; if they
are not, then there is no system. If the
operators have not the time to take read-
ings every hour, let them do so as often
as they can, and when they must skip a
regular reading, let them leave the space
on the log sheet for that time blank. The
recording of pressures on a log sheet
also serves the useful purpose of form-
ing habits of observation as do the in-
spections already mentioned. Observa-
tion is one of the most useful qualities
required of a successful operator and
manager.

kn operating engineer, who some 16
years ago was an assistant in a power
house in the vicinity of New York City,
had a series of experiences lasting over
a period of six months which aptly il-
lustrates the good of "scientific manage-
ment" applied to the engine room. He

October 24, 1911

POWER

621

had erected the engines in this plant, and
was then engaged by the management to
act as repair man and first-assistant en-
gineer. As in many places, there were
cliques formed in this plant among the
older men, who did many things to put
the younger newcomers in tight situa-
tions. The chief was a man who did
not believe men would play serious tricks
on one another, nor would he stand tale
bearing unless backed by absolute proof.
This is a good rule for any man in charge
to follow, and in the end it resulted in
the greatest good to the young first as-
sistant from the training he received.

This was a combined electric light and
railway plant, operating 24 hours per
day. and the work was divided into three
8-hour watches. The relief watches were
instructed to come on a half hour earlier,
and after changing his clothes, each man
inspected the plant in company with the
man he was relieving until satisfied that
he knew all he should of conditions, and
then accepted the plant to operate his
shift. It was this practice that the first
assistant had to cultivate thoroughly in
order to avoid trouble.

He stood a regular watch along with
the two other assistant engineers, and
performed much of the repair work and
keying up with some of the assistants
while standing his watch. One day he
came on watch, and after going the
rounds with the man he was to relieve
he accepted the plant and went about the
regular duties of operation. Soon after
the man whom he had relieved had left
the plant, one of the oilers came to him
and said that the main bearing of one of
the largest engines was hot, and that this
engine had been shut down a few minutes
prior to his coming into the power house.

It was intended that the first assistant
should start this engine and sandpaper
the commutator of the generator which
was belted to it. Too frequently do en-
gineers fall into the habit of starting en-
gines and sandpapering the commutator
of the generators without turning on the
oil. This is a bad practice, but was in
vogue nevertheless.

As soon as the oiler reported that the
main bearing was hot. the engineer felt of
the bearing, something he should have
done while he was making the rounds
with his predecessor. He found the main
bearing so hot that he could not hold his
hand on any part of the box, and the
main shaft was by this time also heating
to the same extent, some little distance
outside of the bearing. The engineer
then lifted the plungers of the oil cups
and allowed them to drop into their usual
notch; this showed that the men who
had been running the engine knew that
the main bearing was hot, for the feed
was so adjusted that the nil was running
from the oil cups in a stream into the
bearing. It also showed that the crew
which had just been relieved had a guilty
knowledge of the condition of the bear-

ing, and had gone off watch without re-
porting it, hoping that their relief would
start the engine and sandpaper the com-
mutator of the generator without going
near the bearing, and thus they would
be able to place the blame upon those
who sandpapered the commutator. Of
course, the engineer had the bearing
stripped and the babbitt was found to
have been "pulled." It necessitated the
whole main bearing being stripped and
the oil grooves chipped out at the top and
bottom and in the quarter boxes, and the
whole bearing rescraped.

.Another custom in this power house
had to do with the starting of the Corliss
engines. At this time, the first assistant
followed the custom of starting the en-
gine by admitting enough steam to just
turn it, and then taking the starting bar,
he would "rock" the piston backward
and forward a few times in order to
thoroughly warm the cylinder and work
out any water which might be entrained.
One day, he started the engine as usual
soon after coming on watch, and after
rocking the piston a sufficient number of
times, he hooked in the reach rod on
the wristplate and let the engine start
off on its travel. Just as he hooked in
the rod, however, and the engine went
over the first center, he noticed that there
was considerable play in the reach rod;
that it seemed to have much more lost
motion than he had ever noticed before.
He immediately brought the engine to a
stop and, looking over the valve gear,
found that the pin connecting the reach
rod with the rocker arm had backed off
so far that the nut on the reverse side
of the rocker arm was only holding the
pin by about one thread; and if the en-
gine had been allowed to come up to
speed, and before the load had been
thrown on. the nut would have worked
off and allowed the pin to fall out of po-
sition, probably resulting in a wrecked
valve gear. The amount of damage it
would have done would have depended
largely on how closely the engineer was
watching everything while starting up.

In this same plant were two vertical
cross-compound engines of 500 and 800
horsepower respectively. These had oil
guards on the sides of the frames which
shut out from view the crosshead as it
worked up and down between the guides.
The oil for all the pins and bearings was
supplied from a reservoir from which
pipes ran to the various points where oil
was needed: one pipe ran inside of these
guards and dropped the oil into a receiver
on the crosshead from which the oil was
carried through a pipe down the connect-
ing rod to the crank pins. The oil
catches on the crossheads were only \i
inch in width, and if the pipe was out
of line the crank pin was likely not to
get the proper lubrication.

After starting the engine one day. and
while still running it slowly before throw-
ing in service, the first-assistant engineer

looked under the oil guards up at the oil
pipes and found that they had been bent
several inches out of line, and that the
oil leading to the crank pin and also to
the crosshead guides was not running
anywhere near where it should. As these
were high-speed engines, it is evident
that much damage would have resulted
by running five or ten minutes in such a
condition.

These instances show that if the engi-
neer who was coming on watch had not
been careful to look over every part of
the engines before relieving the other
man, he would not have been able to
place the blame where it belonged. It
was his method of starting up cautiously
that saved him from more disastrous re-
sults for which he would have received
the blame from the chief engineer.

As previously mentioned, keeping a
log book not only furnishes data from
which rhe operating results can be com-
puted, but it also requires the engineer
to go about the various parts of the plant
at stated intervals.

This was deemed so important in the
plant under discussion that it was finally
made a rule that the engineer in charge
of a watch was to go into every part of
his plant at stated periods to take the
readings and inspect the plant.

At one time, soon after a new addition
had been put in, many of the flanges on
the high-pressure steam mains began to
give out, and the first discovery of a
cracked flange was made while the engi-
neer was going to a certain part of the
cellar to read a vacuum gage on a con-
denser. While passing along the pipe alley
to get to this gage, he heard steam hiss-
ing from some place from which he knew
it had not come before, and following the
noise, he discovered a cracked flange on
a 16-inch high-pressure steam main.

Another time he was going to a different
part of the same cellar and discovered
that one of the laborers who worked
around the plant during the day was
bound asleep in the bottom of a 20- foot
flywheel of a Corliss engine which was
to be started within a few minutes. As
the flywheel was covered over by the
flooring in a manner which permitted only
the spokes and rim to come through the
floor, it is evident what would have hap-
pened to the man; besides, the company
would have been liable to a lawsuit.

Most all large power stations and
steamships have a thorough system of in-
spection both at the time of changing
watches and during each watch, which
follows out the lines herein suggested.
But it is in the small plants in factories
and office buildings that there seems to
be the greatest lack of such a system,
and if every engineer who is in charge
of a plant would think this over carefully
and follow out the suggestion of careful
inspection at all times, there would be
fewer accidents and shutdowns would be
reduced to the minimuin.

622

POWER

October 24. 1911

Stresses in Locomotive Boilers

Herein are set forth a few of the for-
mulas and inetliods used by a prominent
Western railroad in complying with the
new boiler-inspection law of the Inter-
state Commerce Commission, which went
into effect on July 1, 1911. This order
requires a monthly inspection of every lo-
comotive boiler and a report of this in-
spection to be sent to Washington; also,
yearly reports of the condition of the
interior and e.xterior shell, braces, stays,
bolts and seams are required. At this
inspection the boiler is subjected to a
hydrostatic pressure of 25 per cent, above
the working steam pressure.

A specification card for each boiler is
required and this card includes the gen-
eral dimensions and stresses in the most
important members of the boiler. In cal-
culating these stresses, the work of com-
putation is considerably shortened by use
of the accompanying tables. Table 1
shows the area supported by staybolts,
crown stays and crown-bar rivets for
various longitudinal and transverse pitch,

By W. H. Burleigh

Under the new regula-
tions of the Interstate Com-
merce Commission, locom,o-
tives are required to be in-
spected at stated periods
and the reports forwarded
to Washington.

The computations con-
tained in these reports are
facilitated by the use of
certain tables and formulas

ichich are herein given.

Lowest efficiency of longitudinal

seam;
Efficiency of plate;
Efficiency of rivets;

c = Area of telltale hole in square

inches;
h = Pitch of stays, longitudinal a.xis

of boiler;
i = Pitch of stays, transverse axis
of boiler;
p' = Pitch of rivets;
p ^= Pitch of outer row of rivets;
* = Thickness of plate;
d = Diameter of rivet hole in inches;
n = Number of rivets in half the
joint.
To bring a boiler within the required
limits of safety, it is necessary to deter-
mine the maximum pressure at which the
boiler can be safely worked. The law re-
quires that on and after January 1, 1912,
the lowest factor of safety allowed will
be 4. Then in the following formula F
equals 4 and

T X t X E

P = -

(0

T.\BLE 1.

.\UEA .-^

IPPORTED BY ST.WBOLT

Pitch of Staybolts. Inches

H

3,',;

35

3H

3i

3H

31

3H

4

4A

4i

4ft

41

4ft

4 J

4rt

4i

<r

3i

12.3

H

Sft

12.5

12.7

u

3i

12.7

12.9

13.1

3ti
3}

12.9

13.1

13.3

13.5

13.1

13 4

13.6

13. S

14.0

3K

13.3

13.6

13. S

14. (]

14.3

14.5

■^

13.6

13. S

14.0

14.3

14. o

0

?li

13. S

14.0

14.3

14.5

14. S

15.0

15.3

.-

14.0

14.3

14.5

14 S

15.0

1.1. :i

1.5 .5

l.)..S

<

it

14.. i

14.7

15 (1

I.T ■-'

15.5

1,5. 7

16. U

16,3

.p

14 4

14,7

14.9

15 •>

15.5

1....

16.0

16.2

16.5

lb .

14.9

15.2

15.4

l.i.V

16. 1)

16.2

I * Ji I - .>

0

14.9

15. I

15.4
15 B

15.7
15.9

lo.y
Ifi o

16.2
16 4

16...
16,7

16 .

17 0

17.0
17,3

1, .;

17 r.

18.3

i.s.e

—

15.9

16.1

Ifi 4

16 7

16 9

IV 2

17.5

1, s

IS (1 IS .-;

p

16. 1

16.4

16.6

16 9

17 V

IV .-)

IV S

l.s 0

l,s :i IS, 6

IS.S

19.1

19.4

19,6

s

15.7

16.0

18.3

16.6

16.9

17.2

17.4

1V,V

IS.U

KS,.

18.6 1S,.S

19.1

while Table 2 gives the diameter of the
bolts and the areas at the root of the
threads, minus the area of the telltale
hole, which is i'.-. inch in diameter by 1'4
inches deep and is drilled from the out-
side in all short staybolts. This gives
the area at the smallest section of the
bolt and is calculated using the sharp
V-thread.

The following notation is used in con-
nection with the formulas:

P = Boiler pressure in pounds per

square inch;
S = Stress in pounds per square

inch ;
S' = Shearing stress on rivets in

pounds per square inch;
T = Tensile strength of plate in

pounds per square inch;
r = Tension in plate seam of lowest

efficiency;
D = Diameter of boiler in inches;
/ = Area in square inches supported

by longitudinal stay rods;
A = Area of longitudinal stayrod or
gusset plate in square inches;

),■ = Efficiency of plate and rivets;
F = Factor of safety — 4;

The value E may be determined by
analyzing the longitudinal joint for fail-
ure in various ways. In a double- or
triple-riveted butt joint as in Fig. 1, the
joint may fail by one of three ways:
First, a tearing of the plate along the
outer row of rivets; this section of the
plate, minus the diameter of the rivet
holes as compared with the whole section
of the plate, gives the efficiency, or
p ~ d

Second, it may fail by shearing all the
rivets in the joint,

aiiS
■ ptf

Third, by a tearing of the plate along
some inner row of rivets and a shear
of one or more rivets in the outer row, in
which case

Ep=^

Er

(-)

(3)

T.\BLF

2. .\RE.\ OF

.ST.WBOLT. ROOT OF THRE.\D, LES.-i TELI,T.\LE HOLE

.\rea at Root of

Decimal

Diameter at

Thread, I>ess

Equivalent.
Inches

Root of Thread.

Area at Root of

TeUtale Hole,

Inches

Area, Inches

Inches

Tliread, Inches

Inches

J

0.75

0.44179

0.6057

0.2881

0.2605

0.78125

0.47937

0.63695

0.3186

0.291

0,8125

0 51849

0 6682

0.3506

0.3230

^

0.S4375

0,55914

■ 0.69945

0.3842

0.3.566

0.875

0 60132

0.7307

0.4193

0.3917

f.

0.90625

0 , 64504

0.76195

0.45,59

0.4283

0.9375

0.69029

0.7932

0.4941

0.4665

H

0.96875

0.73708

0.82445

0..5338

0 .5062

1

1 . 0000

0.78.54

0.S557

0.5751

0,5475

lA

1.03125

0.83.527

0 , SS695

0.6178

0.5902

ift

1.0625

0,8866

0.9182

0.6622

0.6346

lA

1.09375

0.939.57

0.94945

0.7079

0.6803

IS

1 . 125

0.9940

0 9807

0 . 7554

0.7278

ift

1 . 15625

1 . 05025

1,01195

0.S0428

0.7766

1,'.,

1 . 1875

1 1075

1 0432

0.S547

0.8271

lA

1.21875

1 . 166.59

1,07445

0.90669

0. 87909

11

1.25

1.2272

1 , 1057

0.9602

0.9326

lA

1.2S125

1.2893

1 . 13695

1.01.52

0.98,56

ift

1.3125

1.353

1 . 1682

1.071S

1.0442

(A inch telltale h

ole= 0.0276 .squa

re inch area.)

hole

square

Area of rivet

inches;
; Area at root of thread in square
inches;

The lowest of these efficiencies is taken
s the representative strength of the

October 24. 1911

P O W E R

623

joint when compared with the whole sec-
tion of the plate. Some of the seams are
welded for a short distance at both ends,
but this is not considered in determining
the efficiency of joints.

In double- and quadruple-riveted lap
joints. Fig. 2, or in fact any lap joints,

o o o o o o o
o o o o o o q_o
'6"o'6"d'b"6 o o

o o o o o o o

o

<- _ P X A X t , ^

■=> a -c (5)

The quantities h \ i and a' — c can be
taken direct from the tables and thus
save much mathematical work.

In calculating the stresses in the longi-
tudinal stayrods, the area supported is
taken as the segment of a circle, the arc
of which is about 3 inches from the shell
and the chord 2'_. inches from the top of
the uppermost row of flues. By meas-
uring the rise of this segment and the
length of the chord, the total area can
be computed from the table of areas of
segments found in "Kent's Handbook."

where the diameter of the rivet holes are
taken from the whole section of the
plate.

The Interstate Commerce Commission
allows double shear to be taken as twice
that of single shear; hence for a longi-
tudinal seam.

5' = P X O X p
2 X n X a

(7)

o o o o

Fig. 1

there are two methods of failure con-
sidered, that of tearing of the plate and
the shearing of the rivets, and the effi-
ciencies are found by using formulas 2
and 3. In applying the formulas to the
lap joint, however, the total number of
rivets across the joint is considered.

A joint that presents a high efficiency
■s the Vauclain joint, shown in Fig. 3.
Here the pitch is taken as the distance
between the inner rows of rivets of two
girth seams and the efficiencies are cal-
culated by the same methods and for-
mulas as are used for double- and triple-
riveted butt joints.

The maximum stress to which a stay-
bolt is subjected at the root of the thread
Is given as

Fig. 2

The areas of all the rods are added to-
gether and the pressure multiplied by the
area of the segment, divided by the total
area of the rods will give the stress per
square inch in the rods; or the stress in
longitudinal stayrods or gusset-plate
braces, expressed by formula, is

5=^ (6)

The area A Is taken as the sum of the
areas of the rods or the least section of
the plate, in plate braces generally
through the angle fastening to the heads

Fig. 3

where n is the total number of rivets in
single shear, including each rivet in
double shear being considered as two in
single shear.

The quantity which in the majority of
cases determines the factor of safety of
the boiler is the tension in the plate seam
of lowest efficiency and Is calculated as
follows:

2 X ( X h ^ '

where E is the lowest efficiency of the
plate or rivets as compared with the solid
plate. From this the factor of safety Is
found by dividing the minimum tensile
strength of the plate by the tension in
the plate as found in formula (8).

By the use of the foregoing formulas
and tables. It becomes a comparatively
simple process to fill out the required
specification card for any locomotive
bniicr.

Causes and Prevention of Corrosion

Distilled water rusts Iron more than
do other kinds. Steam as such does not
attack Iron. Both water and oxygen are
necessary to produce rusting. If Iron is
suspended in a vacuum above water (as
in Fig. ll, no rusting will occur because
there is no oxygen present. Paint Is
the only agent available for protecting
iron against rusting.

Effect of the Supply of Oxygen on
Rusting

The rapidity of rusting of Iron In water
is proportional to the amount of oxygen
present. If the Iron is near the surface
of the water as in Fig. 2, rapid rusting
develops, whereas If the Iron is at a
greater depth below the surface as in Fig.
3, the rusting will he much slower. In
the first case, the oxygen of the air
above easily diffuses through the water
and attacks the iron, while in the latter
case, the greater head of water above the

By L. B. Taylor

General cotidition.s coii-
Irolling rusting. Prcsenee
of both oxygen ami uater
necessary.

CO 2 increases the rate oj
n( stint:,.

Diwimihir metals and
iliwiwilar alloys in pliysi-
(ol contact under water,
especially salt water, are
corroded hy galvanic action.

Iron diminishes the diffusion of the
oxygen. Similarly, the rapidity of rust-

ing depends on the surface of the water
exposed to the air. Thus, in Fig. 4, the
rusting will be relatively slow compared
to the case In Fig. 5. where the Iron is
at the same depth below the surface, but
the amount of water surface exposed to
the air is much greater, which permits a
greater amount of oxygen to diffuse
through the water and reach the iron. In
the latter case the rusting may he 30 to
40 per cent, faster than in the former.

Pure oxygen on the surface of the
water, in place of air. can rust the iron
as much as three times as fast. Spread-
ing a layer of oil over the surface of
the water offers no protection, as was
once supposed, since the nil has a great
solubility for oxygen.

If air is forced through the water (in-
fusion of air under pressure) the rapidity
of rusting can be doubled. Likewise,
if compressed air exists ahnvc the water
the tnjsling will be more rapid.

624

P O XX' E R

October 24. 1911

Rusting is naturally greatest at those
places where the supply of oxygen is
greatest; thus, for example, a suction
pipe protruding from the water, as in
Fig. 6, is attacked the strongest at its
point of entrance into the water; that is,
at the water level. Here a rust sponge
is formed, which in itself offers an
easier passage for the oxygen of the air
than is offered by the diffusion through
the water necessary to reach the other
parts of the pipe line.

Since water has a greater ability to
absorb oxygen than nitrogen, air sacks
are to be considered as places in which
a greater concentration of oxygen exists
than in the air, and therefore where more
intense corrosion occurs, especially if,
by a continuous supply of fresh water
containing air, there is a constant renewal
of the oxygen. A few often recurring
examples will illustrate this action.

On a vertical pipe the flanges deflect
the upward currents of water and air
sacks are formed at the places indicated
in Fig. 7; consequently more rapid cor-
rosion results at such places. In large
water pipes, if the bend is too abrupt and
the velocity high, the water does not
flow in parallel streams around the curve
but leaves'the pipe as indicated in Fig.

8, where an air sack or partial vacuum
exists. The greater concentration of
oxygen helps in attacking the pipe at the
inside of the bend and, as the place is
constantly washed clean of rust by the
flowing water, the bend is soon eaten
through. The remedy, of course, is longer
bends, or guiding ribs as shown in Fig.

9, for combing out the streams of flow
and keeping them parallel, a method for
which a patent has lately been granted.

Fig. 10 shows the arrangement of a
hot-water reservoir, the heating coil of
which was ruined in practical operation
by being eaten through in 20 to 30 days,
as shown in Fig. 1 i. The process of rust-
ing may be explained as follows:

The cold water contains air in solu-
tion, which, by the warming up of the
water, separates out to the same degree
as the decrease in solubility. Conse-
quently, deaeration is caused by the con-
tact of the cold water with the lower
coils of the heating coil. The rising air
bubbles so liberated, increasing constant-
ly in number as the cold water con-
tinues to circulate, stick fast to the iron
heating coil, especially at those places
where a roughness already exists. Air
and water act simultaneously on the iron,
and rusting begins. The air bubbles,
liberated by the further deaeration, stick
fast at the rusted places so formed,
which in comparison to the other parts
of the pipe surface become very rough,
thus causing a greater and greater spread-
ing and deepening of the rusted surface,
until finally, a complete rusting through
occurs.

A comparison of two pumping plants
using the same water developed the im-

portant fact that in the one where pump-
ing was done continuously the rusting
was slower than in the other, pumping
intermittently. The explanation of this is
that in the latter more air mixes with
the water during the pauses and this air
aids considerably in the rusting.

Recognizing that oxygen is the real
cause of rusting, means should be taken
to rid the water of it, or to render it
harmless by otherwise combining it before
it enters the water pipes. By boiling
the water or by pumping out, the oxygen,
can be entirely removed, or greatly re-
duced in quantity, but these means can
hardly come into consideration for large-
sized commercial plants since they are
too difficult and costly.

Tests made by suspending charcoal in
the water or by using charcoal for a
filtering material to remove the oxygen
from the water have led to good results.
Here the well known principle is utilized,
that charcoal induces gases to precipitate

the air in the water then changed the
dissolved ferrous oxide into insoluble fer-
ric hydroxide by precipitating the CO;,
which again attacks the iron.

Galvanic Action and Corrosion

It is known that in salt water the ma-
terials common in machine construction,
zinc, aluminum, iron, tin, iron-bronze,
pure aluminum-bronze, ferric aluminum-
bronze, pure tin-bronze (89 Cu 11 Sn),
bronze low in zinc (88 Cu, 8 Sn, 4 Zn),
copper, phosphor-bronze (94 Cu, 6 Sn
with Ph), are corroded by the galvanic
currents developed as soon as they come
into metallic contact with each other.
When metallically connected, a current
flows from any material listed toward the
end of the above series to any one pre-
ceding it, which flows back through the
water from the material nearer the be-
ginning of the series to the other metal,
whereby the material from which the
current flows on entering the liquid is

on itself and holds them fast. Naturally
it. is important to use the deaerated water
immediately or, in case this is not pos-
sible, to guard against resaturation with
air. Quantitatively, if it is assumed that
100 cubic centimeters of water saturated
with air contains 0.8 cubic centimeter
(that is, nearly 1 per cent, by volume)
of oxygen (at 0 degree Centigrade and
760 millimeters barometer), correspond-
ing to 0.00114 gram of oxygen, then
every million gallons of cold fresh water
can convert, in the ideal case, 45 pounds
of iron into ferric-oxide.

Effect of CO, on Rusting

This has in the past been overesti-
mated. Rusting can occur without C0>
Air containing as much as 15 per cent,
of CO. acts onlv twice as fast as air with-
out any CO-. Pure CO. alone cannot
rust iron. The previous theory why water
pipes rusted was that the CO; dissolved
in the water converted the iron into car-
bonic-acid-ferrous-oxide: the oxygen of

eaten away or corroded. Fig. 12 illus-
trates the principle, the plates being
labeled zinc and copper merely by way
of illustration. Thus, by a galvanic element
of two different metals and water, that
metal is as a rule most strongly attacked
which stands nearest the zinc in the
series given above. The arrangement of
the series of metals in the order of their
voltages depends on the liquid used. The
series must therefore be determined in-
dividually for each liquid. The fact that
when iron under water is in contact with
zinc (he rusting of the iron is consider-
ably reduced or completely overcome, has
long been used in practice for boiler
plants, especially on ships, as well as in
condensers and pipe lines.

An interesting discovery of the cause
of boiler plates corroding near the weld
is that if the plates are overheated in
welding and are not hammered until
they have reached red heat, when put
into use a current is set up as
indicated in Fig. 13. The current

October 24, 1911

POWER

625

flows from the normal part of the
plate through the water to the previously
overheated joint and back through the
plate. The metal is corroded as indi-
cated where the current passes from the
plate to the water.

Effect of the Composition of Metals
ON Galvanic Action

The following tests, conducted at the
German government laboratory, on the in-
fluence of the contact of different metals
with iron, show the general tendencies.
although they are only exactly true for
the special conditions under which the
tests were conducted.

Iron in contact with copper was rusted
in fresh water 25 per cent, faster and in
artificial salt water 47 per cent, faster
than if by itself. The conclusion is drawn
that by means of the copper the oxygen
dissolved in the water acts on the iron
electrode with a greater intensity than if
the contact with the copper electrode did
not exist.

With reference to the contact of iron
with nickel, tests conducted with dis-

tilled water showed that the iron was
coated with 14 per cent, to 19 per cent,
more rust than when not in contact with
the nickel. A homely illustration of this
is shown by the fact that the steel blade
of a safety razor rusts much faster, if
left wet, in contact with its nickel-plated
holder than it would by itself.

With cast iron in contact with a piece
of welded steel pipe, tests at room tem-
peratures showed that the steel was
strongly protected by the cast iron. With
air passing over the surface, the rusting
was reduced 50 per cent., and by air pass-
ing through the water it was reduced 28
per cent. The same tests at temperatures
between that of the room and 140 degrees
Fahrenheit, using well water, showed that
the rusting of the steel was reduced 16
per cent, on the average, at the cost of
the cast iron. The idea that cast iron
by itself rusts less than steel by itself
is not true. There is not much differ-
ence in the rapidity of rusting between
cast iron, wrought iron or steel. The scale
on iron castings and their greater thick-
ness of wall may make them last longer.

Phosphorus and Nickel in Steel

If a steel high in phosphorus is in
contact with one low in phosphorus in
salt water, the former will be protected
and the latter will rust faster. Nickel
in the steel has a similar effect. From
this the conclusion is drawn that steels
v.ith important differences in composition
should not be connected if external con-
ditions favor a galvanic element.

Copper .'\lloys

.An alloy high in zinc is attacked con-
siderably faster in salt water than in air,
and still more so if it is in contact with
other metals. The corrosion of copper
alloys with 24 per cent, zinc takes place,
by the galvanic current, if it is in con-
tact with copper or alloys high in copper,
almost as it would on other copper al-
loys, principally from the outside. With
28 per cent, or more zinc the corrosion
is considerably greater. By adding 15
per cent, nickel, copper alloys high in
zinc will be better protected against cor-
rosion.

Developments in Prime Movers

Steam Turbines

The steam turbine for power-plant
work has been developed in Europe with
great rapidity within recent years, so that
almost every large engine builder is now-
able to furnish steam turbines. In Ger-
many the impulse type of turbine is
built almost exclusively, while in Eng-
land and Switzerland the modified reac-
tion type seems to be in the lead. Fig. 1
shows a section of the Zoelly turbine,
which is characteristic of the German
impulse types. It is built by Escher,
Wyss & Co., Gorlitzer, Frazer & Chal-
mers, James Howden & Co., John Brown
& Co.. Oerlikon, Sautter, Harle & Cie,
and several other firms.

The Curtis turbine has been built by
a number of firms in Europe, but it has
been superseded to a large extent by
the combined type of turbine which is
now being largely constructed in Europe
and which has been very fully described
in recent issues of Power in the articles
by F. E. Junge and E. Heinrich. This
type of turbine, a sample of which is
shown in Fig. 2, consists of a Curtis
high-pressure stage combined with either
a Zoelly or a Rateau low-pressure ele-
ment. It is claimed for this type that
there is no high temperature inside the
casingf as the temperature is reduced in
the noz'Ics and in the first revolving
blades of the Curtis clement. Also, it is
not necessary to provide high-pressure
packing on account of the decreased pres-
sure in the turbine after the steam has
been expanded in the nozzles. The clear-
ance can be made quite large, hence the
machine will not be subject to mechanical

By A. G. Christie

C oiitiiiitatioi ()/ arliclc ni
the September 12 issue. In
the present insialDioil
European practice in steam
turbines, condensers, elec-
trical apparatus, gas en-
gines and oil engiiies is
rcviexved and compared with
A moh (III nil Ihinty.

defects or blading troubles. The Curtis
high-pressure section seems to have
proved the most economical construction
for the utilization of high-pressure steam,
while either the Zoelly impulse or the
Parsons type seems to be the most eco-
nomical in the low-pressure section. The
combined-impulse type, with the Curtis
high-pressure section, is now being man-
ufactured by the Allgcmeine Elektricitiits
Gesellschaft. the Bergmann F.lcktricitiits
Gesellschaft. the British Thomson-Hous-
ton Company, and the British Westing-
house Companv. The modified-rcaction
type is manufactured by almost all the
companies which formerly built the
straight Parsons turbine, and among
these arc Brown. Rnvcri & Co., Melms &
Pfenningcr. Willans & Robinson. C. A.
Parsons &• Son. Franco Tosi. Cebruder
Sulzer and the Rrste-Brunncr Company.
One of the officials of Brown. Bnvcri
K Co. recently stated that they had found
that the modified reaction type gave an

increase in economy of 10 per cent, on
low-speed turbines over the old Parsons
t\pe and an increase of about 4 per cent.
on the high-speed turbines. It is claimed
for these modified turbines that there is
less distortion of the cylinder due to high
temperatures than in the old Parsons ma-
chines; also, when the Curtis stage is
used in the high-pressure section the ma-
chine can be made shorter and is more
perfect mechanically since the distance
between centers is less, and the spindle
can be made rigid. The high efficiency
of the Curtis stage for high-pressure
steam is combined with the high effi-
ciency of the Parsons stage for low-
pressure steam, so that the resulting unit
is more satisfactory in operation than
either the straight Curtis or the straight
Parsons types.

The governors used on these turbines
are generally of the Hartung type, such
as is used in this country on the Allis-
Chalmers steam turbine. Governing is
cff'ected by throttling the steam through
the medium of nil-relay valves. On the
impulse turbine extra nozzles arc opened
bv hand for the heavier loads with the
exception of some of the newer Allgcmeine
Elektricitats Gesellschaft turbines, where
these arc opened bv the governor. The
writer did not notice any switchboard
speed-control devices on any of the tur-
bines in the power plants throughout
Europe. This is quite common practice
in America

The blading of nianv of the impulse
turbines is completely cut from solid
metal by means of milling machines and
their special cutters. This insures very

626

P O W F. R

October 24, 1911

homogeneous material and also overcomes
the difficulties frequently met with from
straining the material by forging it or
pressing it into shape. In the Bergmann
turbine, however, sheet-metal blades are
used throughout, the distance pieces be-
tween the blades being of drop-forged
brass. These sheet-metal blades are held
to the disk by rivets and form a very
rigid and apparently economical construc-
tion.

Turbo-generators

The tendency throughout Europe is to
utilize higher speeds for steam turbines
with a view to attaining more economical
results. As excellent steel forgings can
be obtained cheaply in Europe, the rotors
of the generators can be run at high
speeds. The stators in some machines
do not seem to be of very good construc-
tion as compared with American practice
as the windings appear to be rather
loosely put in and the installation is not

collected from various authorities and also
a number of tests made on American tur-
bines. The turbines showing the highest
efficiencies are the 2000-kilowatt and the
6000-kilowatt units built by the Erste-
Brunner company. These are of the
modified Parsons type. The next tur-
bine in the order of high efficiency is
the Dunstan-Parsons, which was built by
Brown, Boveri & Co. and is also a modi-
fied Parsons type. The fourth on the
list is an American machine, the AUis-
Chalmers unit at Richmond, Va. This is
the first straight Parsons unit on the
list. Following this comes the City Elec-
tric Company's Westinghouse machine,
a double-flow unit, and the Brooklyn
Rapid Transit's Westinghouse, double-
flow machine, which are also modified
Parsons units. From this it is seen that
the turbines which have shown the best
efficiencies in Europe and in America,
with the exception of the Allis-Chalmers
machine, have been those of the com-

not hold true for marine practice, where
most of the more modern ships are be-
ing equipped with high-pressure steam
engines and low-pressure turbines.

Condensers

In Germany a type of condenser
is largely used in which bronze tubes
are rolled into the tube sheets, the con-
denser shell being of boiler plate. It is
claimed that the bronze tubes are cooled
by water to a lower temperature than
the steam temperature in the condenser,
while the condenser shell is warmed to
the same temperature as the steam it-
self. Hence, the expansion of the steel is
relatively greater than the bronze tubes,
so that in operation these two equalize
one another and no trouble is experienced
with leaking tubes due to expansion. In
the Moabit station the writer was shown
a condenser on a 40C)0-kilowatt turbine
which had been in ser\'ice for three years,
and on which no repairs had been made

Fig. 1. Section through Zoelly Turbine

up to our standards. The Bergmann com-
pany manufactures a large number of
direct-current machines with heavy steel
rings shrunk on the commutators. Inter-
poles are also used to prevent sparking
at the brushes. However, these ma-
chines are extremely noisy and do not
seem to fulfil the ideal requirements of
a direct-current turbo-generator. An in-
teresting departure from standard prac-
tice is shown on the Westinghouse di-
rect-current turbo-generator, which is pro-
vided with a radial commutator so that
the evil effects of centrifugal force are
largely overcome. This commutator
runs very quietly and apparently has
given good satisfaction, the only difficulty
being to obtain sufficient commutation
surface without crowding the brushes.

The accompanying table, page 630,
shows the results of a number of recent
European turbine tests which have been

bined type. The manufacture of the
modified types of turbines with the ex-
ception of the Westinghouse double-flow
machine has not been taken up to any
extent in this country, but in view of the
success with which they have met in
Europe, it would seem that their manu-
facture must be taken up in earnest be-
fore long in America.

Low-pressure turbines are being built
to a large extent in Europe, but are be-
ing installed in old plants only or around
collieries and rolling mills where engines
have formerly been run noncondensing.
In a few plants they have been installed
where the engines are comparatively new
and where it was not desired to throw
the engines out entirely, but as a com-
mercial proposition it is not considered
desirable to install high-pressure engines
and low-pressure turbines where a new
plant is being built. This statement does

to the tubes. The water supply for this
condenser was taken from a neighboring
canal and was not ideal by any means.
On the Continent rotar>' air pumps are
used almost exclusively. Many of these
are of the Le Blanc type, while others
are of the type shown in Fig. 3, in which
the air is pumped by the injector action
of the sheets of water thrown out by a
small centrifugal pump. Fig. 4 shows an
installation in which rotar>' air pumps
of the Allgemeine Elektricitats Gesell-
schaft type are installed in connection
with the main steam turbines. In Eng-
land the three-throw Edwards air pumps
are still favorites and are used almost
exclusively in the larger plants. Many
of the steam-turbine plants are equipped
with Parsons vacuum augmenters and
some remarkably high vacuums are ob-
tained by this means, but the equipment
with this apparatus and with the Edwards

October 24. 1911

POWER

627

pumps takes up much more floor space
than the rotary air pumps of the Le Blanc
type; it is doubtful whether they are
more reliable or efficient in operation
than the rotary type.

Cooling Toixers

Cooling towers are very generally used
throughout Europe. The majority of these
are built to utilize natural draft. In Ger-
many a large number are being built of
reinforced concrete and are extended up
to a considerable hight to provide a
chimney effect which will increase the
draft. They look very substantial and are
quite in harmony with the architectural
design of most German plants.

Electrical Machinery

The electric drive has not been applied
so generally in England as in this coun-
tr>' because of the conservative attitude
of most of the mill people. The switch-
boards in the majority of power plants
are built along the same lines as those
employed in America. One station in the
north of England is building all the
switchboards of planished steel. The
switches, which are principally of the re-
lay type, are mounted on insulators on
these boards. This construction is not
only of pleasing appearance but is ser-
viceable, is easily kept clean and is said
to be cheap as compared with a marble
board.

matic voltage regulators in all stations
except those of very large size. On the
Continent practically all substations em-
ploy motor-generator sets instead of

place of flywheels and thus reduce the
floor space required by the gas-engine
unit. At one of the large steel works
electilc heaters are provided to heat the

Fig. 3. Section through Rotary Air Piimp

rotary converters. The electric motor rims for shrinking on car wheels. This

has not been introduced in steel-mill method is said to be much more rapid

practice to any great extent, although the and less costly than the former practice

Cockerill company has one rolling mill of heating with gas, besides producing

Fig 2. Combined Type of Turbine

One notices the lack of switchboard electrically driven. The Rencratnrs fur- a more uniform heat throuEhout the rim.

speed control of the main units in almost nished by several builders for conncc- The Sicmcns-.-^chuckcrt Company fol-

all European power plants. Another tions to gas engines arc provided with lows the practice, common in this coun-

noticeablc feature is the lack of auto- exfrctnely hraw rninrs. which take the try, of insulating the commutator seg-

628

P O W E R

October 24. 1911

merits of its direct-current machines for
only part of ttie deptl:, the outer radial
section of probably 'i inch between the
bars being left open without insulating
material. It is said that this does not
collect dirt as the centrifugal force throws
it out from between the bars; should dirt
collect there, it can be easily cleaned
when the machine is shut down. The
advantage of this constniction is that the
brushes wear the bars evenly and there
is less liability of sparking.

Another interesting construction fol-
lowed by this company where large cur-
rents are to be taken off the commutators
is to split the commutator in the center
of its length and to connect the two
halves by flexible copper connections. 1 he
outer half is built on a ring which stands
out from the main shaft itself, and is
provided with some small blades which
force the air through the split portion of
the commutator when the generator is in
motion and thus assist in cooling the com-
mutator segments. It is said that less com-
mutator surface has to be provided and
better commutation results than with the
ordinary construction of the commutator.

This company also employs the vac-
uum system for impregnating its elec-
trical machinery with the insulating com-
pounds. It has a cylindrical shell of suf-
ficient size to accommodate a large-sized

with a vacuum pump. The temperature
of the interior is raised to about 250 de-
grees so as to evaporate any moisture
which may be in the windings of the

for a sufficient length of time to insure
the removal of all moisture and air, the
air pump is shut off and the tank is al-
lowed to fill with the insulating com-

-iG. 5. Horizontal Type of Diesel Engine

electrical machine placed on the truck.
At the same time the vacuum produced
will cause any air bubbles or pockets
which may occur in the insulation to

Fig. 4. Power St.mion of A. E. G. Factory. Berlin, Showing Rotary Air Pomps

truck. Both heads of this shell can be
closed and hermetically sealed. The in-
terior of the shell is lined with the steam
pipes, and the upper portion connects

swell and expand and find a way to get
out from under this insulation and be
finally removed by the air pump. After
the machine has staved in this chamber

pound. The machine remains in this
liquid for a time sufficient to insure the
impregnation of all parts of the insula-
tion, after which the compound is run
off and the windings are dried. All large
transformers for high voltage are treated
in the same way.

The city of Schaffhausen, Switzerland,
has resorted to an interesting scheme in
connection with its hydroelectric plant.
There is a considerable fall of water
available at this place, but it has been
developed at several points by small
mill owners and others who have in-
stalled old-fashioned, inefficient machin-
ery in such a way that the full benefit
of the fall is not had. The city was
unable to arrange with these concerns
whereby it could dam the river and de-
velop the full head available; hence It
had to be content with a certain amount
of water at a small head to which it was
entitled by its charter. In order to carr\'
a maximum load with the flow available,
the city constructed a concrete reser\'oir
of 300,000 cubic meters on a hill ad-
jacent to the town. It also installed in
the plant some high-pressure centrifugal
pumps which can he connected to the
low-pressure turbines and which elevate
the water from the river into this reser-
voir during the night and at periods when
the load on the station is light. During
the peak loads in ihe afternoon the water
is drawn from this reservoir and passed
through a high-pressure hydraulic tur-
bine direct connected to a generator. It
is estimated that the efficiency of this
system is about 50 per cent,, but the
power costs in this neighborhood warrant
its installation, and satisfactor>' results
are said to have been obtained ever since
the plant was installed.

October 24, 1911

P O W E R

629

The Stumpf Direct-flow Steam Engine

Professor Stumpf, of the Charlotten-
burg Technical High School, has intro-
duced in Germany a type of steam en-
gine known as the direct-flow engine
which deserves careful attention. The
results obtained have been so remark-
able that the reciprocating engine is in-
sured a new lease of life, at least in the
smaller sizes. This engine was described
in the January 31, 1911, issue of Power.

Gas Producers

The suction-gas producer is very com-
mon in England, where anthracite coal is
used almost invariably. These producers
are nearly identical with those used in
the United States except in certain fea-
tures of detail and in the grate surface.
With the English anthracite coal it is
possible to use a much smaller grate sur-
face than can be employed with Ameri-
can coals. Several attempts have been
made to develop tar-free producers for
bituminous coal in England, but of these,
the only one which the writer noted in
successful operation was that built by
the Morton Gas Power Syndicate, of Man-
chester, England. This was a down-draft
producer with a secondary air inlet at
one side, which, owing to the construction
of the producer, seemed to be providing
tar-free gas. although a certain amount
of lampblack was formed. The producer
is built with rectangular sections, which
is not common practice in the United
States.

A considerable number of bituminous
producers are used throughout England
in connection with byproduct recovery
plants. On account of the advanced state
of chemical manufacture throughout
Europe, these byproducts are of con-
siderable value, especially the benzols,
tars and ammonium sulphate. In Ger-
many the gas producer is not nearly
as commonly used as one is led to be-
lieve from reports frequently published
in the technical press. In fact, the writer
saw only a few producer-gas plants dur-
ing his whole trip on the Continent. The
Diesel engine, to which reference will be
made later, seems to have replaced to
a very large extent the producers former-
ly used on the Continent. Peat and
li,gnite producers have been developed in
Europe and some were being constructed,
although none was seen in commercial
operation.

Gas ENGfNEs

The small-sized gas engines built both
in England and on the Continent em-
body many fine features of construction.
As a rule, the frame is massive and
heavy flywheels are also provided. The
valve gear is mechanically controlled and
the ignition is generally of the magneto
type with a battery for starting. Many
different methods of governing are em-
ployed, some of them of very interesting

and excellent types. The large-sized en-
gines built in England do not seem of as
good construction as those built in
America, and they compare most un-
favorably with the ones seen in Germany.
The large-sized German engines are
probably the best built engines of their
class in the world. Practically all of
the engines driving electric generators
are of the four-stroke cycle type. Many,
if not all, of the blowing engines in the
ironworks are of the two-stroke cycle
type, of which particular mention may
be made of the Oechelhauser, the Kort-
ing, the Siegener and the Ehrhart &
Sehmer engines. The design of the firm
first mentioned has been materially al-
tered within recent years. The construc-
tion which it formerly used and which
employed two pistons acting in opposite
directions with three cranks on the shaft,
has been abandoned in favor of a design
following very closely the original Kort-
ing type.

The gas-cleaning systems in the iron-

an equivalent B.t.u. value in coal at S2
per ton.

HuMPHREV Gas Puvtp

The most interesting development in
gas-engineering lines is the Humphrey
gas pump, which was recently described
in Power.

Diesel Engines

Probably one of the most impressive
engineering features in Europe is the
phenomenal development of the Diesel
engine. This is now seen everywhere, in
hotels, department stores, factories and
power plants. It is much more common
than any other recent type of engine.
In England the London Electricity Com-
pany has installed oil engines of the
Diesel type to carry the peak loads at
substations and thus relieve the power
plant of excess capacity. The Berliner
Elektricitats Gesellschaft is also said to
be considering a similar installation. Sev-
eral large ships, notably the "Vulcanus,"

Hl(.. (). KStKJ-HORSEPOVk ER T\X0-STR0Kt XlKilCAL DiESLL EnGINL

works of Germany have not been per-
fected to the same extent as those of
similar plants in this country. The Ger-
man engines seem to operate satisfac-
torily even with the much dirtier gas used
at their plants, so that one is led to ques-
tion whether the additional expense and
trouble taken to«clean the gas in Ameri-
can steelworks is justified by the results
obtained with the engines. It is common
practice in Germany to use grease lubri-
cation on all pin joints on the gas en-
gines and everywhere else that it is pos-
sible to use it.

The writer was furnished with figures
on the cost of producing power at one
of the large German steelworks, which,
when transformed to American money,
arc as follows: fl.12.'' cent per kilowatt-
hour, operating charges only; 0.2 cent
per kilowatt-hour, operating cost, with
cost of gas included; 0.4 cent per kilo-
watt-hour, including all costs, interest,
depreciation and taxes. The cost of gas
in the foregoing figures was based on

which has been described in recent en-
gineering publications, and a new Ham-
burg-American liner of 3000 horsepower,
have been fitted with Diesel engines. Al-
together, 250 ships have been or are be-
ing fitted with this type. It has been
rumored recently in engineering period-
icals that the German navy is at the
present time installing 10,000 horsepower
of this type of engine on one of its new
^attleships. When the writer visited the
Maschinenfabrik, Augsburg-Niirnberg,
a 2000-hcrsepowcr. six-cylinder, vertical,
double-acting Diesel engine of marine
type was on lest. This one was said to
be intended for a ship of the German
navy, although it was not made public
on which one it would be installed.

Among the leading manufacturers of
this type of engine in England are Wil-
lans & Robinson, Mirriless-Watson and
Richardson-Wcstgarlh; and on the Con-
tinent, the .lohn Cockerill Company,
Carels Frcrcs. Schneider & Cic. The
.Maschinenfabrik, Augsburg-NCrnberg

630

POWER

October 24, 1911

builds vertical two-stroke and four-stroke
cycle units, and it is said to have
built over 1700 Diesel engines up to
the present. Within the last year it
has developed a new horizontal type
of engine, shown in Fig. 5, which follows
the standard lines of construction of
European gas engines. Quite recently
the same company contracted for a 2000-
horsepower horizontal engine for Halle
on the Saale, Prussia. This unit will
be a four-stroke cycle, double-acting,
two-cylinder, tandem engine operating at
150 revolutions per minute and direct
connected to a direct-current generator,
coal-tar oil being supplied as fuel. The
compression will be between 500 and 600
pounds per square inch»

Gebruder Sulzer have probably taken
the leading position in the development of
the Diesel engine in Europe. They are
at present prepared to furnish vertical

1.2 to 1.5 times the volume of the work-
ing cylinders is required to produce the
proper scavenging and to provide a fresh
charge of air for the ne.\t stroke.

Almost any kind of oil which can be
pumped may be used in these engines as
fuel. On the Continent, coal-tar oils
are largely used, thus utilizing a bypro-
duct from city gas works and that which
had formerly been wasted by producer-
gas plants. On these engines it is cus-
tomary to start with kerosene or some
other light oil and run until the engine .is
warmed up, when the fuel-oil pump is
switched over onto the heavy oils. Only
one fuel valve has been found neces-
sary with all classes of oils, and only
one is now installed on the engines.

The marine Diesel engines are now
designed to correspond very closely to
the standard design of modern steam en-
gines. All parts are made accessible for

EGONO.MV TESTS OF E.NGINES AND TURBINES

Based on Marks and Davis Tables

In Calculatins Rankine B.t.u. an Efficiency of 90 Per Gent, is .\ssumed for the Turbine and Generator.

Turbines

Erste-Brunner

Erste-Brunner

Dunstan. Parsons

*Rictiraond, .\llis-ChaIniers. . .
*Citv Electric. Westinghouse .

*B.R.T., Westinghouse

Manchaster, Howden

*N. y. Edison, Westinghouse.

Zoelly, Charlottenburg

Bergraann

Brown, Boveri

*Boston Edison, Curtis

.4. E. G., Moabit

Carville, Parsons

Zoelly, .\ugsburg Niirnberg. . .
*New York Edison. Curtis No. 10

A. E. G., Rummelsburg

Varberg, De Laval

♦Chicago Edison. Curtis

2.000
6,000
6,257
4,328
8,563
11,601
6,383
9,870
2,052
1,545
3,500
5,195
3,169
5,164
1,250
8,921
2,177

161.5
191.0
204.0
186.0
183.0
192 0
203 . 0
192.0
200.0
195.0

>S

Ifi?

n

ISO

0

1S5

0

215

0

188

0

190

0

198

5

172

3

199

0

118.0
194.0
176.0
108.0

59.0
114.0
137 . 0

97.0
202.0
201.0
133.0
142.0
215.0
121.0
204.0
111.0
272.0
170.5
143.0

27 82
2S.12
29 . 02
27.97
28 . 10
27.82
27.40

27. 19

28 . 39
28 . 54
28 . SO
28.74
29.00
28 . 96
28.79
28.10
29.32
28.49
29 36

11

cu

13.84
12.58
11.95
14.02
14.43
14.23
14.30
15 . 05
13.05
12.97
13.72
13.52
12.70
13.18
13.10
14.86
11.77

w =

>« =

O.T

2 a?

~s

<3*^S

a

~B

274.5

218. 4

259.5

205.6

249.4

190.8

278.3

211.6

280.5

211.8

282.8

212.3

285.8

213.7

294.6

219.5

271.6

200.5

270.3

199.1

278.6

203.3

276.1

199.3

268.4

192.8

268.8

192.4

274.5

196.2

296.0

208.8

257 . 1

180.9

337.9

206 6

263.9

184.1

73.9
73.6
72.9
72.2
71.8

'-\merican built turbines

units ranging from 15 to 4000 horse-
power of both two-stroke and four-stroke
cycle types and also double acting. Fig.
6 shows one of these vertical engines
of the two-stroke cycle type.

The latter type will probably supersede
the four-stroke cycle type, especially on
large engines. The reason for this is
that the purging of the cylinder on a
Diesel engine does not entail any loss
of fuel even should a certain amount of
incoming air pass out through the ex-
haust pipe. This is because the fuel is
not added until the air in the cylinder has
been compressed to maximum compres-
sion. In the vertical cylinders it is com-
mon practice to have the lower part
of the cylinder act as an air compressor
for the upper part and to provide an
auxiliary compressor on the end of the
shaft to make up the extra air neces-
sary for the complete purging of the
cylinder. It has been found that from

repairs, and with no unnecessary weight.
The pistons are. as a rule, cooled with oil
instead of water, so that should any
leakage occur there will be no damage
done to any of the wearing parts. This
oil is cooled in a separate cooler be-
fore recirculation in the pistons. The
pistons themselves are now being made
very much like the standard steam-en-
gine pistons. In the land type of en-
gines considerable discussion has re-
cently taken place regarding the relative
merits of the trunk piston as compared
with the narrower steam-engine piston
provided with guides and crossheads. It
is probable that the latter type will be
adopted and the engines will be made
double acting. This avoids leakage of
gas into the engine room and also makes
the engine smaller for a given power.
The fuel consumption of these engines
ranges about 0.4 pound of oil per brake
horsepower-hour.

The development of the Diesel engine
in Europe has progressed much more
rapidly than in America, and the details
of the engine have been worked out so
carefully that engines can now be so
built and installed that no trouble will
develop as regards their operating qual-
ities. In every respect the reliability of
such a type of engine is no longer ques-
tioned to any great extent on the Con-
tinent. With the large supply of liquid
fuels in America and their low cost in
certain sections, it would seem imperative
that American engine builders consider
this new type more carefully and develop
it to the same extent that it has been
developed in Europe. Steps have already
been taken by several prominent com-
panies in America, and it seems prob-
able that in the near future engines with
as fine records as the German engines
will soon be common in American power
plants.

Oil Can Stand

A neat, convenient oil-can stand can
be made by getting a piece of iron plate
7 inches square and ',s inch thick, to
which four curved legs of >4-inch flat
iron are bolted. The legs are strengthened
by rods running through them as shown.

Oil Stand

The cross rods are held in place by a nut
on each side of each leg.

On top of the iron plate an oil tray
is secured, in which the oil cans are set.
This makes it convenient for keeping
clean and also for moving the stand from
one machine to another.

October 24. 1911

POWER

631

Y2 ^ '-:^ „^-. '--,'*. ~

''^

Induction Motor Repairs
By R. H. Fenkhalsen

The Stator Winding

The

motor

previous articles on induction-
repairs were confined to work
which was almost purely mechanical in
:haracter; therefore no electrical knowl-
edge or experience was necessary to
inake the repairs described. The repair
of stator windings involves work of a
distinctly electrical character, and, al-
though it is undoubtedly possible for any
mechanic of fair ability to successfully
rewind the stator of an ordinary induc-
•ion motor by the aid of the instructions
given in this article, the work will be
ereatly facilitated and its quality im-
proved if a fair knowledge of the ele-
•reniary principles of induction-motor op-
eration is possessed by the repair man.
A discussion of induction-motor phe-
nomena does not come within the scope
'.f this article, but a careful study of the
following brief description of the induc-
tion-motor field winding will aid the non-
electrical worker who through necessity
may be compelled to attempt repair work
of this nature.

The stator core of an induction inotor
(often called the field) is magnetized

Fig. I. Diwi.CT-cuwRENT Field Magnet

to Rive alternate "north" and "south"
poles exactly like a direct-current motor
field magnet, but unlike the direct-current
field magnet this polarity is only rela-
tive and its duration only momentary, be-
cause it is created by alternalinK cur-
rent, which reverses the polarity of each
pole .SO or 120 times per second, depend-
ing on whether a 25-cycle or a fiO-cycle
circuit is the source of current supply.

fectly symmetrical and the "poles" must
be formed by proper connections between
the coils.

CoN'CENTRic Coils

There is one type of induction-motor
stator winding which bears a marked re-
semblance to its direct-current prototype,
namely, the "concentric" winding. A sin-
gle-phase stator with this type of winding

Moreover, the bore of the field magnet
is a finely notched circle instead of being
broken up into a number of smooth but
widely separate faces, as in the direct-
current machine. In a two-phase motor
there are two, and in a three-phase motor
three, separate sets of polar faces or
zones, each set being symmetrically
spaced around the circle and alternately
north and south in polarity. For all prac-
tical purposes the repair man may regard
the winding of each phase as a separate

Fig. 2. Alternating-current Stator

direct-current field winding and make
his connections accordingly.

On all direct-current motor field mag-
nets, except the consequent-pole type,
each magnet pole is provided with a coil
containing many turns of wire, slipped
over an iron core projecting inwardly
from the frame, as shown in Fig. 1. The
induction-motor stator. on the other hand,
has nn projecting poles, but consists
merely of a perfectly symmetrical toothed
ring built up of thin iron sheets. The
slots between the teeth may be cither
partially closed, as shown in Fig. 2, which
illustrates the stator core before the coils
arc in place, or else wide open, depend-
ing upon the design.

Fig. .1 shows a stator with wide open
slots and with all the coils in place. It
Is evident from inspection of Figs. 2 and
3 that the frame and winding arc per-

Fig. 3. Distributed Stator Winding
Secured by Lacings

is shown in Fig. 4. The polar faces are
quite distinct, but arc distributed over
several teeth exactly as in the winding
shown in Fig. 3.

Overlapping of Phases

The several series of "poles" forming
separate phases on a two-phase or three-
phase stator will be found to overlap one
another by about one-half or one-third
of the pole pitch. This is very clearly
shown in Fig. vS. which illustrates a two-
phase concentric winding for ten "poles."

The coils of one phase are flat loops,
but the coils of the other phase are
bent outward at the ends to pass under
the flat coils of the first phase. It will be
noted that each pole group spans its full
share of the circumference of the stator
bore, and the span of each group in one
phase is from center to center of ad-
jacent groups of the other phase.

This overlapping of phases is char-
acteristic of all polyphase windings, and
does not cause opposition between the
poles of the different phases, as might
appear at first glance. The reason for
this is easily seen when the lime lag of
the phases is taken into consideration.
Thus on a two-phase motor when the

632

POWER

October 24. 1911

poles of one phase are at maximum
strength, the other phase is at zero, and
vice versa. It is this action which pro-
duces the "rotating field" which forms
the basic principle of induction-motor op-
eration. Fig. -S should be referred to
when endeavoring to trace the sym-
metrical windings to be described further

Fig. 4. Single-phase Concentric St.^tor
Winding

on, as it will aid the reader in his efforts
to locate the polar faces and phases.

Location of Faulty Coils

The first thing to do to a faulty stator
is to clean it thoroughly and wash off all
grease with gasolene and waste. The
next thing is to raise the stator on a
couple of horses, which will enable the
worker to obtain a clear view of all the
coils without lying on his back on the
floor. Some workers have a strong ten-
dency to assume this position, but it is
not conducive to either rapid or accurate
work.

The two phase windings of a two-
phase machine are independent, but the

loads. Another cause of open circuits
is grounds which clear themselves by
burning off a wire, opening the winding
at the same time. Tests for open cir-
cuits should preferably be made with
some source of low voltage such as a
vibrating bell and a few cells of dry bat-
ter>'. It often happens that a wire breaks
and pulls apart when the motor is in
service and hot. By the time the motor
is stripped it will probably have cooled
sufficiently to bring the ends into partial
contact. If the test is made with a high
voltage, it is very probable that no faujt
will be indicated, but if only a few volts
are employed, the relatively high resist-
ance of the imperfect connection will
either prevent the bell from ringing or
give only a very weak ring as compared
with an unbroken circuit.

Open circuits are most liable to occur
in the cross-connections between poles.
These should be carefully tried by bend-
ing, as a broken wire inside the taping
will be indicated by increased fiexibility
at the break. If no broken connections
are noted a coil to coil test must be made.
Much time will be saved by the use of an
insulated testing handle, made out of a
file handle in which has been driven a
wire brad ground to a needle point at one
end, as shown in Fig. 6.

One end of the test circuit may be fast-
ened to one terminal of the motor wind-
ing and the test point thrust through
the taping of each coil terminal in turn.
As soon as the open circuit is indicated
by no ringing of the bell, the fixed ter-
minal of the test circuit should be moved
to the other end of the motor w^inding
and a coil to coil test made to make sure
that there are no open circuits in that

Fic. 5. Two-phase Concentric Stator Winding

windings of three-phase machines are in-
terconnected either "star" or "delta"
fashion and it is necessary to open these
connections before the winding can be
tested.

In order to locate "open" places in the
winding, each phase must be tested sep-
arately. Open circuits may be caused
by vibration, which in time makes the
wire break, or to badly soldered joints
w-hich "blow" like a fuse under heavy

part of the winding. A magneto is un-
suitable for this test because it will give
a ring through from 10,000 to 50.000
ohms and would not detect a loose con-
tact. By far the best testing instrument
is that described in Power of May 11,
1909, for locating broken end connections
in direct-current armatures, but owing
to the higher relative resistance of an
induction-motor winding the bell and bat-
tery will give excellent results.

If broken end connections are found
they should be repaired but if the "open"
is in a coil the coil must be removed,
although for temporary operation it is
permissible to bridge over the faulty coil,
as this is not as harmful as in the case
of direct-current apparatus.

If an open circuit is found and re-

FlG. 6. Af-PLIA.Xchs FOR TESTING A StATOR

Winding

paired, all the other tests such as grounds,
crosses, etc., should be made; a motor
often is affected in several ways simul-
taneously. A careful series of tests may
therefore save dismantling the motor a
second time.

Grounds

Weak places in the original insulation,
extreme vibration, or oil spilled over tTie
coils often lead to grounds. Excess oil
soon rots the insulation and impairs its
insulating quality, allowing a small cur-
rent to flow from the winding to the
motor frame, which carbonizes the oil and
insulation until a breakdown occurs.
The ground test must be made with high
voltage, preferably double that of the
motor. The full line voltage will, of
course, do, but its use gives no assur-
ance that any factor of safety is pos-
sessed by the insulation.

It is the writer's practice to test all
J50-volt m.otors at 1000 volts between
the frame and winding for ten minutes
and 2000 volts on all 440-volt motors.
This gives ample assurance that the in-
sulation will not break down upon the
occurrence of a slight increase in line
voltage. If these voltages are not avail-
able, an old autotransformer out of a
2000-volt auto-staner may be rigged up
as a booster, or one may be made as
shown in Figs. 7 and 8. taps being taken
out at the proper points for the 1000-volt
test and the 1 10, 220 or 440 primary
as indicated in Fig. 9. For 2000 volts
the number of turns will be about 20.000
divided by the number of square inches
in the core. This coil must be well
insulated between layers and from the
core.

The full test voltage must never be ap-
plied between the winding and the frame
until a preliminary test in series with a
bank of lamps has been made, because a
violent short-circuit would result if a
heavy ground existed and the resulting
flash would be liable to damage a large

October 24, 1911

POWER

633

part of the winding. The lamps are also
valuable as an indicator, as they will light
up dimly even on a poor ground. Con-
trary to the opinion held by many elec-
trical workers, the presence of the lamps
in series does not materially lower the
applied voltage at the motor because in
most cases only about 5 per cent, of the

- «-»— 1^: : : -n

/

1
-f

/

^

^•'

Fig. 7. Transformer Data

voltage is across the lamps, the other 95
per cent, being available for the test. The
full voltage test may be made in series
with a small fuse, provided the lamp
test indicated no trouble.

Crossed Phases

This test must be made after the open-
circuit and ground tests and is made in
exactly the same manner and with the
same voltages as employed in the latter,
with the exception that the test voltage
instead of being applied between the
winding and the frame is applied between
the various phases. If either a ground
or a cross between phases is indicated
in the preliminary test, all the connec-
tions between the groups of each wind-
ing should b^ carefully moved away from
the frame and from each other to insure
that there is no trouble at these points.
Crossed phases usually occur between

Secordary
•r<-??OOV->{

^s^^fi^-Xiiooa

circuits seldom occur except as a result
of contact between end connections, in
which case their presence would natural-
ly be revealed and corrected when the
end connections are raised for the ground
test. Short-circuits of individual coils
are of rare occurrence, and do not result
in such extensive damage as on a direct-
current motor. Their presence is easily
detected by the partly charred condition
of the insulation. A heavy overload is
liable to char the entire winding so badly
that the insulation between turns is de-
stroyed, in which event the only remedy
is complete rewinding of the stator.

Finding the Faulty Coil

After the general nature of the fault
has been determined, the exact location
of the defective coil must be found. The
"cut-and-try" method is most commonly
used. The faulty phase is first cut in
two by unsoldering the cross-connection
between the central groups. The fault
is then localized in one half, and that
half is divided and subdivided until the
exact coil is found.

A method used by the writer will lo-
cate the faulty coil exactly without open-
ing any connections, and occasionally it
is possible to detect the fault and re-
pair it without even removing the rotor,
only one end bell being removed to give
access to the winding. Almost every in-
duction-motor installation is lighted from
a 110-volt single-phase circuit, and this
source of current and a voltmeter with a
125- to 150-volt scale are all that one
needs to locate a faulty coil accurately.

If the stator winding of the motor be
connected across the 110-volt circuit, the
flow of current will not be excessive,
especially if the rotor is in place, and an

r

<i-U40V

\,440V J XX

Pri-rar

Fig. 8

Fir.. 9

frame. It is evident that the voltage
indicated on the voltmeter will bear the
same relation to the line voltage that the
coils bridged by the voltmeter do to the
total number of coils.

Suppose, for example, there are 36
coils connected across the 110-volt cir-
cuit, and a voltage indication of 82'/';

the lop and bottom coils in one slot and
may be repaired by raising the lop coil
and after carefully taping the fault, in-
serting a new separator of micanite or
treated cloth between the coils.

Short-circuits

Short-circuits usually result from two
or more simultaneous grounds or crossed
phases and therefore may disappear when
such defects have been repaired. Short-

T G
Of Motor frame

Fig. 10

auloiransformer effect will occur, giving
a potential across the terminals of each
coil equal to the applied voltage divided
by the number of coils per phase; each
phase is tested separately, of course.
This effect may be utilized as indicated
in Fig. 10.

One phase of the stator winding is
connected across the 110-volt liRhiing
circuit and the voltmeter is connected
between one stator terminal and the

Fic. 11. Extra Meter Scale

110:82'/.;: :36:27, so that 27 coils are
bridged by the voltmeter.

This means that the ground is be-
tween coils 27 and 28, counting from the
terminal to which the voltmeter is con-
nected, and the exact value obtained indi-
cated a grounded end connection between
groups, especially as the value is exactly
three-fourths the full voltage, which
would only occur between poles on a
four-pole machine. As the voltage across
each coil equals 3.05 volts, any indication
nn the voltmeter not exactly divisible by
this number will indicate a ground w-ithin
.1 coil. Owing to the more open char-
acter of the voltmeter scale above half
voltage, due to the longer and more uni-
form division', tlie ungrounded voltmeter
terminal should be connected to that ter-
minal of the stator which gives the high-
est reading. When the reading is near
half scale the mean of the readings from
opposite ends should be taken.

Crossed phases are located in the same
manner as grounds except that one ter-
minal of the free phase is used instead
of the ground. The voltmeter will indi-
cate the coil (in the phase under test)
which is crossed with the other phase. If
desired a check test may be made with
the phases interchanged, the phase which
was used as a "ground" in the first
. test being connected across the line and
the other one left free.

If much testing is to be done a spe-
cial scale may be made to slip over the
regular voltmeter scale, divided according
to the number of coils per phase. In the
writer's plant .3(5, 48 and 64 coils per
phase cover all motors that fall below
100 horsepower, making 18, 24 and 32
divisions respectively, between the 55-
and llO-voIl marks on the scale. By
reading the proper scale the number of
the defective coil is indicated directly.
.'Vs the voltage scale is not evenly divided,
neither will the coil scale be, so the
voltage per coil must be calculated for
each scale and the values interpolated
from the voltmeter scale for each coil
division, as shown in Fig. II. In using
this auxiliary scale, the voltage at the
terminals of the one stator winding must
be maintained exactly at 110 during the
test.

634

POWER

October 24. IPll

, -

"^ nt

> — '

The Care of Oil Engines

By John S. Leese

Starting Up

When tne engine attendant gets to
know his engine it will be found advis-
able to always leave the control levers,
after shutting down, in the starting-up
position. The manipulation of these soon
becomes mechanical. To start the engine:

1. Light the lamp to heat the vaporizer,
if one is used.

2. Oil up all around, and in cold
weather see that the oil in sight-feed
cups is dropping freely.

3. See that the inlet and exhaust
valves do not stick in their guides, ap-
plying kerosene if they are at all sticky.

4. Engage the compression-release, if
one is provided.

5. If electrical ignition is used, retard
the spark; if tube ignition is used, see
that the tube is hot enough for a start
but not too hot or it will cause kick-backs.

6. Open the fuel feed and, if neces-
sary, pump up the pressure to force
the fuel into the vaporizer.

7. Turn the engine over by means of
the flywheel or a crank, or set into action
the starting gear, taking care that the
engine crank is in the right position be-
fore turning on the compressed air.

8. As the engine gets up to speed,
throw off the compression-release and
set the ignition- and fuel-control levers
at their running positions. (It will often
be necessary to "starve" the engine of
air at starting up, but as it gets up to
speed it should be allowed as much air
as possible consistent with good firing.)

9. Turn on and regulate the water
supply.

10. It is often advisable to let the en-
gine run light for a few minutes after
starting up from all cold in order to let
the parts get properly warmed up to their
work. In fact, where ignition is by tube,
it is, in most cases, sure to stop the en-
gine if load is put on before the tube is
properly heated up.

Running

To keep the engine running properly:
1. Keep the water-discharge tempera-
ture constant. In order to maintain the
water at the proper temperature, which
is about 140 degrees Fahrenheit, the
water should pass from the engine to the
drain in the open air and the temperature
kept under observation by permanently
setting a thermometer in the stream. On
hot days and with full loads, the water

in the cooling tanks, if they are used,
may begin to boil. In this case it w^ill
be advisable to run off some of the water
and replace it from the source of supply
with cold water, making sure that the
level is carried above the upper pipe
opening.

2. Keep the fuel supply up to the de-
mands of the load; if it is fed by pres-
sure, see that the filters and pump valves
do not get clogged.

3. See that lubrication is regular and
sufficient.

4. In cold weather and in all winter
months drain all the water out of the
jackets and the entire cooling system, in-
cluding radiators if these are used (not
the tanks, of course i. to prevent trouble
from freezing.

Shutting Down

To stop the engine:

1. Throw off the load.

2. Cut off the fuel supply.

3. Switch off the ignition or turn out
the lamp and open the compression-re-
lease if one is fitted.

4. Turn off all oil cups and other
lubrication feeds.

5. If the engine is connected up to the
exhaust pipe of another engine in such
a way that the other engine could blow
into its cylinder, turn the crank over into
such a position that the exhaust valve
will be shut. If the engine has a sep-
arate exhaust pipe, stop with the piston
at the end of the outward stroke with
the exhaust valve open.

6. Cut off the water supply after the
engine has cooled down. If the water
be allowed to cool down in the jacket
and is, on restarting, heated up again,
scale may be formed.

Cleaning Oil Engines

Always keep the outside of the engine
free from oily and greasy smears. If
oil is allowed to get on the concrete
foundation it will do it no good and
make the engine room no handsomer. If
the engine is not already provided at
the bottom of the bed with an oil channel.

sawdust should be laid around the bed-
plate to soak up the oil.

The best time for cleaning the outside
of the engine is immediately after or
just before shutting-down time, while it
is warm. Engine attendants with chil-
blains will have found this out for them-
selves in the winter time.

The amount of internal cleaning re-
quired depends largely on the type of
engine, the kind of fuel and lubricating
oils used and the load carried. It should
cover the combustion head, piston, valves
and ports, vaporizer, spark-plug points
(if any I, cylinder walls and oil passages.
Some system is advisable in these per-
iodical cleanings. The writer advises the
following order of procedure:

1. Take out, clean and replace all
filters and valves in the oil-supply sys-
tem, including the pump, if any; these
parts should be tightened down again
ready for running again as soon as they
are replaced.

2. Remove and clean the vaporizer,
inlet and exhaust valves and cages, and
internal ignition devices, but only the lat-
ter if they are easily removable.

3. Grind in the inlet and exhaust
valves if necessary.

4. With the crank on the inner dead
center and the exhaust valve in place,
clean as much of the deposit and dirt out
of the combustion space as possible
through the inlet-cage openings. This
tends to prevent the possibility of grit
finding its way onto the cylinder walls.

5. Remove the piston and finish clean-
ing out the combustion head and cylinder
walls.

6. Clean the piston, oil ways, rings,
etc., seeing that the rings are free in
their grooves and removing all deposit
with a scraper, preferably made of cop,
per. If all the rings are free they need
not be taken off, but if they are removed
see that the grooves receive attention.
The removal and replacement of the
rings should be done with great care. It
is not an infrequent occurrence to find,
after breaking a ring, that the stock
keeper has neglected to renew his supply.
Rings are best loosened by first soaking
in kerosene and then, if still obstinate,
they can be judiciously clouted with a
piece of wood. Another good but little
known dodge to ease the removal of de-
posit and piston rings is to stand the
piston, immediately after it is taken out
of the engine, in a bucket of hot water
and soft soap.

7. Replace the piston, inlet valve,
vaporizer and other parts, tighten uo all

October 24, 1911

POWER

635

nuts, and turn the engine through a com-
plele cycle in each direction to see that
all is free.

8. Start up to see that the running is
all right, testing the power, if necessary,
with a plank or flywheel brake.

Troubles

The following are the chief and most
troublesome of the irregularities in the
running of an oil engine. In diagnosing
complaints system must be used in order
to eliminate, one by one, the possible
causes of trouble:

1. Engine will not start.

2. Engine will not start, although ex-
plosions are heard.

3. Engine starts but soon stops.

4. Engine can only be started up after
much cranking.

5. Engine starts up but runs spas-
modically.

6. Engine stops after running some
time and then refuses to run again.

7. Explosions in the inlet pipe.
S. Knocking.

9. Engine does not develop its power
and will not carry its load.

10. Engine runs too fast.

Taking these faults in order, (1) re-
fusal of the engine to start may be due
to the vaporizer being either not hot
enough or too hot; too little oil; exces-
sive or insufficient air supply; electric-
ignition trouble. The remedies for all
these causes of failure to start are suffi-
ciently obvious with the exception of that
relating to electrical-ignition troubles.
These are so numerous and varied that it
is impracticable to discuss them ade-
quately here; they would require an arti-
cle to themselves.

2. If the engine will not start, although
explosions are heard, this indicates that
the exhaust valve requires attention. It
may be that the spindle is sticking due
to deposits or to being too tight in its
guide, or that the valve has some dirt
en its seat, preventing it from closing,
or needs grinding in. Here, again, the
remedies are obvious, although it may
be worth while to point out that to make
the valve spindle easy in its guide kero-
sene should be applied, not lubricating
oil, as the application of that would tend
to increase the trouble when the spindle
got heated up.

3. If the engine starts but soon stops,
ignoring the possibility of electrical-igni-
tion trouble, the cause of stopping may
be due to insufficient pressure on the fuel
or lamp supply: faulty mixture (too little
or too much air); an overload or too
early application of the normal load;
cooling of ignition tube; mechanical
trouble, or lubrication failures. The
remedies for all of these are obvious.

4. Difficulty in starting may be due
to a variety of causes, such as valves
sticking, valve springs being weak or
broken, actuating mechanism being dis-
arranged; loo little fuel or too much air;

ignition tube not hot enough. If any of
these causes exist, the engine will not
fire quite regularly immediately after
starting but may do so after missing a
few explosions. In the case of valve
trouble it may be that the constant heat
and stress to which the exhaust-valve
spring is subjected in the course of work-
ing has destroyed its temper. In case of
poor mixture the ignition tube must be
heated to a temperature which will ignite
poor charges. In general, the poorer the
mixture the hotter the tube must be kept.

5. Irregular running is not infrequent
with oil engines fitted with rotary gov-
ernors working on the hit-and-miss prin-
ciple. The cause can generally be traced
to sticking governor parts, excessive play
in the governor-mechanism joints or a
badly worn pecking blade. Governors
should be kept well lubricated with a
rather thin oil to prevent their sticking.
An occasional dismantling and cleaning
with kerosene is advisable. Inertia gov-
ernors are less likely to cause irregular
running because they have fewer wear-
ing parts.

Another cause of spasmodic running is
irregularity in the flame of the lamp,
generally due to the nipple being fouled
with carbon.

6. When an engine stops and refuses
to start, this may be attributable to igni-
tion failure; fuel-supply failure; loss of
compression, due to leaky valves, slack
valve-cage nuts or a leaky vaporizer or
igniter joint; defective lubrication, or ex-
cessive back pressure. The last men-
tioned trouble may be due to the gradual
accumulation of water in the exhaust
pipe or the muffler or to the shifting of a
piece of asbestos packing in the exhaust
line.

7. Explosions in the inlet pipe may be
caused by the ignition of the mixture
upon the opening of the inlet valve; the
explosion of the vapor given off by the
lubricating oil, or insufficient jacket cool-
ifig.

The first cause may be brought about
by the continued or protracted burning of
the previous charge until the inlet valve
opens for admitting the fresh one. In
this case the mixture is too weak, due
either to loo much fuel oil or loo little
air, causing slow combustion. Another
cause may be the incandescence of car-
bonized oil or thin webs or points of
metal in the combustion chamber, which
ignites the fresh charge as it is drawn
into the cylinder. If there is a joint in
the wall of the combustion chamber and
the gasket is not carefully trimmed on
the inside, the fibrous ends of the as-
bestos may remain red hot and cause
this trouble. If there arc any small
pockets or recesses inside the combustion
chamber, where gases could continue
burning more or less sheltered from the
currents caused by the opening and clos-
ing of the valves, il is very often the

case that these "fire pockets" ignite the
incoming charge.

The respective remedies for these cases
are, of course, to correct the mixture,
clean and scrape the combustion cham-
ber of dirt and projections and, where
possible, plug up recesses. If the ex-
plosions are traced to the vapor given off
by the lubricating oil it is time to change
the oil and get a kind suitable for oil-
engine work. A good-sized volume could
be compiled on the requirements and
properties of lubricating oils for gas en-
gines and oil engines. Many owners seem
to think that these can be interchanged
with impunity, and pay a big bill for
week-end engine cleaning in consequence.
8. Engine knocking. The trained en-
gineer will soon be able to distinguish
the sort of knocks due to slack bearings,
premature ignitions and too violent igni-
tions. Premature ignitions produce a
sort of dull, bumping noise and can, with
little experieiice, be distinguished from
explosions which are merely violent but
properly timed. Too early firing may be
occasioned by too hot a tube or too early
timing, too rich a mixture, too hot a
vaporizer, too much compression, insuffi-
cient cooling or an overheated charge
remaining in the cylinder because of a
previous misfire.

Violent explosions are in nearly all
cases due to too much fuel or an exces-
sively hot vaporizer.

While on the subject of pounding it
is worthy of note that the all too com-
mon knock of a loose flywheel is the most
deceptive of all. It should be corrected
at once, of course. If the flywheel key
be well driven in as soon as the knock
is located, damage to the keyway and
possibly fracture of the wheel hub may
be avoided.

9. Inability of the engine to carry
the load or run up to speed may be due
to any one of the following causes:
Faulty mixture; too early or too late
ignition timing; poor compression; dam-
aged or weak valve springs; sticking
valves, or damaged valve mechanism;
governor set too slow; lay-shaft gear
wheel meshed wrong with crank-shaft
gear.

Poor compression is the only cause re-
quiring discussion. The best way to lest
the compression is with an indicator but
if one is not at hand it should be noted
whether oil blows past the piston, through
the valve guides, etc. Grinding in the
valves will often make a quite unex-
pected difference in the running of an
engine. One method of finding leaks is
by applying soapy water to the sus-
pected parts and watching for bubbles.
A leaky piston has a peculiar hiss of ils
own, although the writer has found that
in engines with no "outside" piston
ring this hissing is only heard when the
leakage is excessive.

Other causes of loss of power and
speed arc general wear of the valve-gear

636

POWER

October 24, 1911

parts and back pressure in the exhaust
pipe.

10. Excessive engine speed is always
rectifiable by adjustment of the governor.
The remarks under the heading of ir-
regular running (trouble No. 5) apply
in this case. ■

Dangers

By way of conclusion it may be use-
ful to point out some of the dangers
arising from the use of oil engines. The
greatest is, undoubtedly, the inflamma-
bility of the fuel. All pipe and flange
connections in the oil lines must be kept
tight and the cover should never be left
off the fuel tank. In taking down an
engine it should always be seen that the
ignition, if electric, be switched off. When
either the valve cover or the ignition ap-
paratus has been removed from the cyl-
inder it is well to hold a lighted taper
in the combustion space to ignite any
inflammable vapor that may be lurking
there. -JChen doing this the piston should
be at the end of its outward stroke and
the operator's face should be kept well
away from the open apertures.

Many fatal accidents have occurred
through engine operators starting up by
putting their feet on the flywheel spokes
or gripping the rim in such a way that
their arms project between the spokes.
In swinging engines over the compres-
sion point the wheel should be released
as soon as it is found that the crank
will not go over with the one pull. Back-
fires have wiped out several attendants
who were overpersistent in this direction.

Porcelain ignition tubes should never
be closely examined when the engine is
under power as the bursting of one of
these, a not uncommon occurrence, gen-
erally results in the blinding of the in-
spector,

America's Undeveloped Peat
Bogs

The great peat deposits of the United
States seem destined to remain an unde-
veloped resource for some time to come
because of ignorance of their practical
value. According to Charles A. Davis, in
an advance chapter on the production of
peat from "Mineral Resources of the
United States," for 1910, which is issued
by the United States Geological Survey,
noteworthy progress was made in 1910
in the production of peat fuel in other
countries not only in the quantity actual-
ly marketed but also in methods of pro-
duction and utilization.

In a recently perfected European gas
producer it has been found that in con-
verting peat containing a good percentage
of nitrogen into gas a large amount of
ammonia, greatly valued as a fertilizer,
can be obtained as a byproduct. Mr.
Davis quotes from a report which shows
tVat where gas-producer plants using
peat are carefully managed so great are

the profits obtainable that it is often
possible, while taking no credit whatever
for the value of the power gas, to obtain
as much as 100 per cent, profit from sul-
phate of ammonia alone, after making
proper allowance for the cost of digging
the peat, bringing it to the plant, and
for labor, stores, fixed charges, etc. In-
deed, with peat comparatively poor in
nitrogen, it is possible in many cases
to produce the gas for nothing, the cos;
of power being then merely that of op-
erating the gas engines, together with
capital charges on the engine plant.

Although these claims may be some-
what optimistic, says Mr. Davis, it is
clear that if each ton of theoretically dry
peat gasified yields from 75,000 to 90,-
000 cubic feet of producer gas, the heat
value of which is from 125 to 135 B.t.u.
per cubic foot, and also gives 200 pounds
of sulphate of ammonia as a byproduct,
the operation of a plant consuming 10
tons of dry peat fuel a day would pro-
duce daily a ton of the ammonia salt,
worth S60.

Mr. Davis believes this process is of
practical application in the United States
and should be investigated carefully by
owners of American peat lands, many of
which are very rich in nitrogen; some
Government analyses show as high as
3.39 per cent, of combined nitrogen.

LETTERS

A Looped Diagram and
Late Ignition

In a recent issue of Power, J. C. Par-
mely gave the indicator diagram shown
in the figure, taken from a 100-horse-
power producer-gas engine, and stated in
explanation of the loop in the diagram. that
it "was taken with the igniter retarded
as far as possible from the normal op-
erating position, which was about 25 de-
grees ahead of the dead center," and that
"according to the diagram, the ignition
occurred slightly beyond the dead center
and I think the igniter was set about 10
degrees past the dead center." The loop
in the diagram, he said, "is probably due
to the cooling influence of the jacket
water, decreasing ,the volume of gas
until the moment when ignition oc-
curred."

I cannot agree with Mr. Parmely in
his analysis of the diagram. Whenever
the ignition of a producer-gas engine is
delayed as late as this one was, 10 de-
grees past dead center, the engine is
liable to backfire, or preignite, or both.
This is due to the fact that late ignition
makes the gas burn very slowly and it
frequently burns so long that a flame
persists in the cylinder during the suc-
tion stroke. If this flame is in a part
of the cylinder close to the inlet valve,
the incoming charge of gas and air is
ignited before the inlet valve closes and
the engine backfires with a loud report

in the air-intake pipe. This cannot be
detected in a diagram. If the flame is
in a part of the cylinder away from the
inlet valve, the ignition occurs after the
inlet valve closes and burning gases are
compressed instead of cold gases. This
can always be detected in the diagram
by the long, easy curve of compression
which reaches a peak and descends along
the same curve or a sharper one, and the

Scale. : 240 Pounds
per Inch

Retarded Ignition

expansion results in no power being gen-
erated. In this diagram the expansion
line is much sharper than the compres-
sion line, making a negative loop in the
diagram. The negative loop in a dia-
gram which shows preignition is due
to the influence of the cooling water
v.-hen the piston is standing still. This
diagram is unquestionably one showing
preignition due to the delayed ignition.
C. C. Austin.
Streator, 111.

Gasolene in the Crank Case

In the September 26 issue, Lloyd V.
Beets relates some troublesome experi-
ence with gasolene getting into the crank
case of a two-stroke cycle engine.

I was much interested in the article, as
I have seen and operated a great many
two-stroke gasolene engines on the river
at this point. But I have never had any
trouble similar to that described by Mr.
Beets, although I have nad cases where
gasolene got into the crank case, due to
trouble in getting an engine started,
when the carbureter would overflow. But
after the engine was in operation and had
got warmed up the excess gasolene soon
became vaporized. For a two-stroke
gasolene engine to work properly and at
its best economy, the gasolene should be
thoroughly vaporized -by the time it
reaches the crank case, and the internal
heat and compression should tend to dry
the mixture rather than permit it to con-
dense.

It is my opinion that the cause of the
trouble could be traced to the carbureter,
which might be defective or not closely
enough adjusted, and therefore was feed-
ing more gasolene than could be vapor-
ized, or that the carbureter overflows
and leaks into the crank case when the
engine is not in operation. Possibly if
the carbureter were more carefully ad-
justed it would eliminate the necessity
of using the heavy cylinder oil and the
economy in gasolene consumption would
be very noticeable.

L. M. Johnson.

Glenfield. Penn.

October 24, 1911

P O W F. R

637

'^^%r

a.

^^^i-^^ ^^jr'--: J' l--w-:■a,Oi-•■-T-

'5

Unbalanced Fields

I recently inspected a 500-kilo\vatt
vertical Curtis turbine which vibrated so
badly that bricks and mortar were
loosened in the walls of the building.

My report, "field needs balancing,"
did not meet with the approval of those
in authority and another man was put on
the job.

He went through the supposedly re-
quired stunts of taking down the step
blocks and guide bearing and renewing
them, inspecting the middle and top bear-
ings and transposing the governor bal-
ance weights, etc. The chief performer
then declared the machine to be all right,
but the operator thought otherwise, and
not without reason, for the old complaint
was still apparent when running with a
full load.

Shortly after, a batch of experts ar-
rived; then another, and finally the "last
resort" appeared on the scene. The
peculiar gyrations and acrobatic feats
practised by the electors of this office
suggested wireless-telegraph men. The
wireless man, nervous of step, walked
ten paces to the right, looking first at
machine, then at the operator: five paces
to the left and, as before, looking serious
all the while, with an air of one who
held the key to the undeveloped mysteries
cf t^ie tventieth century. He climbed
the ladder, and after salaaming three or
more times to the governor dome, looked
around the room once more and shook
his head. Then he nervously jerked out
a knife from his hip pocket and started
down the ladder like a streak of lightning.
This was too much for the natives who
had been following every move with mis-
givings, and they bolted for the door.
I intercepted the runaways and persuaded
them to remain, reassuring them that all
would be well, as the critical point had
now been reached.

Bebold! The wireless man took the
■ nife handle in his teeth, and pressed

'-• blade against the wheel casing, put a

ger In his ear, and thus completed his

J- nervations.

In due time the verdict came: "Proceed

10 and install new top bearing;

rolhing serious with machine, it always
'•as run pretty good; not much of a job,"

!C.

I knew that the machine did not need
a new top bearing any more than a dose
of castor oil. I knew that it was out
of electrical balance; for every time the
current was thrown on or off the field a
lar roiiM h" felt on the platform, and

Practical

information from the.

man on the job. A letter

^ood enough to print

here will he paid for?

Ideas, not mere words

wanted

the force of this kept pace with the
strength of the Held.

It was only a matter of determining
which field was- at fault. This was done
by measuring the drop across the re-
spective fields with a voltmeter and in
this case inserting a very heavy weight
diametrically opposite the field indicat-
ing the greater number of ampere turns.

This turbine has now been in oper,T-
tion Quite a while and no complaint about
the old trouble has been made.

The top bearing was left in the base-
ment and has been forgotten.

George Davis.

Lowell, .Ma?s.

Suction Lift of Pumps

The accompanying diagram shows a
series of curves which provide an easy
method of ascertaining, the maximum
suction lift that a pump is capable of
dealing with at various altitudes.

These curves are based on theory with
suitable corrections from practice for
mechanical efficiency, leakage and air
pressure and have proved very useful
to me in my work.

W. Vincent Treeby.

Kssex, England.

Lap Seam Fractured

I had been at work in a New England'
city for several days doing external in-
spection and was making my last visit
for the day. The boiler was of the two-
plate type, having a diameter of 54
inches: the plate was ,;. inch thick. When
I opened the furnace door the sound
of escaping steam and water could be
heard. I examined the tubes at the rear
end and found them tight. I inquired
of the engineer if he was aware that the
boiler was leaking and he said that he
was, and was going to shut down either
Labor day or Thanksgiving day and try
to find the leak. I immediately went to
the office and explained to the manager
that it would be necessary to close down
at once for an examination. He informed
me that the boiler would be ready the
next morning.

I then applied a hydrostatic test and
considerable leakage developed. As the
source of the leakage could not be seen,
the brick covering was removed and a
fracture about 18 inches long was found

Wafer h'mperaiure WaterTemp- Wafer le-vp. '/taterTemp. WaterTemp

ISODeq^Fnhr. iSODeg.Fahr. l?00iqF,ihr 90DeqFahr. 600eq.Fahr

Vfjpor Tepsiorj Vapor Tension VaporTension VaporTension VaporJensiori

7.5lb.persq.in. i.l06lb.persqm l.6S3lhpersq.in. 0.69}lhpersa.in atiblbiier^jn

5 K) 15 20 25 5 10 15 ?0 25 5 10 16 ?0 25 5 10 15 ?0 25 5 10 15 20 25
Feet '^"■

Chart Civinc. Suction Lift of Pumps

638

POWER

October 24, 1911

running through the rivet holes of the
longitudinal seam, and directly under
the rear lug on the right-hand side.

A new boiler was at once installed
and when the old boiler was cut up the
fracture was found to be over 36 inches
long on the inside and partially through
the plate. The working pressure was
80 pounds per square inch and furnished
power for a three-story building.

E. E. Edcett.

Bridgeport. Conn.

Pressure in Pump Discharfre
Pipe

A 16 and 10 by 14-inch duplex steam
pump discharges through a 6-inch pipe
C to an open tank A. The pressure in
the vertical pipe C, and against the check
valve D, due to the hydrostatic head, is
80 pounds per square inch. Between
the check valve and the pump is a 3-
inch pipe E which leads to another open
tank B. This pipe is fitted with a valve.

The pressure against the pump, due to
the hydrostatic head in the pipe E, is 20
pounds per square inch.

sure in the discharge pipe above 80
pounds per square inch, or enough more
than 80 pounds to lift the check valve D.

I would like to hear from Power read-
ers on this subject.

J. F. Murphy.

Sheboygan, Wis.

Burning Fuel Oil

When burning fuel oil the air should
be admitted directly under the flame and
the air opening should conform as nearly
as possible to the shape of the flame.
This air opening should also be sub-
divided into many small spaces to pre-
vent too large a volume of air striking
the flame in one spot.

After adjusting the burners so that the
fires are even and are burning intensely
enough to carry the steam at the desired
pressure, the dampers should be adjusted
until the fires are a trifle smoky or giv-
ing a light yellow haze. If the steam
pressure raises, as it probably will, owing
to the better combustion obtained, lower
the fires a trifle and adjust the damper as
before. An Orsat apparatus is most use-
ful in determining the damper positions.

Experience has shown that about 10
per cent. CO; is good average practice in
oil burning. In cases when two or more
burners are installed under one boiler,
the fires must be kept as nearly as pos-

LoCATiON OF Cages to Determine Pressure in Discharge Pipe

The question is, Can the pump, run-
ning at a piston speed of 100 feet per
minute, discharge enough water so that
the check valve D in the 6-inch pipe will
be lifted, and water be forced into the
pipe C, or is the 3-inch pipe £ large
enough to discharge to the tank B all
of the water the pump can deliver? If
it is, the pump cannot raise the pres-

sible of the same size and intensity. If
they are not so arranged, it will not be
possible to so use the dampers as to ob-
tain the most economical draft. When
the fires are found to be burning in a
satisfactory manner and the dampers
have been set at the correct position,
nothing remains to be done but keep
"hands off" and refrain from meddling.

The fires should be inspected every hour
or so in order to see that the burners
are properly working.

When the oil burners are supplied with
oil under pressure, it has been found
that a ratio of 2'., or 3|4 pounds of steam
to 1 pound of oil is about correct for
atomizing purposes. The steam used by
the burners for atomization of the oil will
range from 2 to 5 per cent, of the total
steam generated by the boiler, according
to the type of burner used.

The burner which atomizes the oil with
the least amount of steam is the more
economical oil burner. It does not matter
whether it be an outside- or an inside-
mix burner.

WiLLiA.M Pattern.

San Antonio. Texas.

Machine for Cleaning Oily
Waste

Economy in the consumption of cotton
waste in engine rooms may be easily
effected by the adoption of a cleaning ma-
chine built by our engineer, such as is
shown in the accompanying sketch.

The material used in its construction
was gathered from a nearby scrap heap
of car parts and consists of two cast-
iron flanges, two supports, a 5-inch pul-
ley, four 18-inch bolts and about 7
square feet of sheet iron. The fianges
were drilled to receive the four bolts and
turned down on their centers to be used
as axles. These flanges were old trolley
stands taken from discarded cars. The
supports, parts of an old exciter bed,
were drilled to act as bearings and are
held in place by being bolted to the floor.
The sheet iron forming the can was man-

^^

Waste Cleaner

ufactured from an old oil can and was
perforated by means of a nail and ham-
mer. This can was placed inside the
long bolts, which were run through pieces
of ' -inch pipe. The flanges could then
be drawn up tightly to the pipe without
buckling the can. A door in the can gives
access to the interior. Through one flange
a '^.-inch pipe is loosely fitted, which
carries the steam to the interior of the
can for the purpose of separating the
oil from the waste.

A speed of 1800 revolutions per min-
ute is maintained, which is sufficient to
remove oil from 3 pounds of waste in

October 24. 1911

POWER

639

15 minutes. A sheet-iron canopy covers
the entire machine and keeps the oil frorji
flying about.

T. T. LoGiE.
South Norwalk. Conn.

Connecting up CO.. Recorders

Where it is necessary to use three or
four CO: recorders on a total of 40 to
50 boilers I have found the piping ar-
rangement herein described to be quite
satisfactory. The system is cheaply in-
stalled and is easily blown out and
drained.

In Fig. 1 is shown an elevation of the
boilers and general layout of the piping.

This line from the junction A contains
the filter, as shown in Fig. 2. Each line
connected with the junction is provided
with a valve and inclosed in a box, so
that, if necessary, by manipulation of
the valves, the fireman may be kept in
ignorance as to which boilers or boiler
the machine is connected; hence he can-
not be partial to certain fires and must
run them all economically in order to
produce a good chart.

These lines become stopped up quite
frequently with soot. Therefore, a perma-
nent steam connection (compressed air
is better I is made to the lower extension
of the header B. All valves are closed
and the top of the filter is removed until
valves C and D are opened; then each of

TestLines.^

Header to Recorder

^ I

1

1

, 1

<?

II

5tejrv or Compressed Air
j[^ -J

Fic. 2. METHnn OF Connecting CO.. Recoroer to Several Uptakes

A '.-inch pipe runs from the middle of
the last pass in each boiler to a header
that is located at the center of the sys-
tem, and is easily accessible. The header
then runs to the recorder, which is placed
in front of the boilers where the mini-
mum amount of piping possible will reach
it, and in a cool, light place where it
cm be easily watched by the Hremen.

the valves in the headers is opened sep-
arately and the line is given a thorough
blowing out. As all the lines pitch to-
ward the left, the moisture of condensa-
tion is drawn off every few days by open-
ing the valve C until it has had time to
run down in the pipe; then it is closed
and the valve F is opened. In this way
no air is allowed to enter and the steady

flow of gas to the recorder is not im-
paired.

In like manner the condensation is
drained off at the recorder by means of
the extension fitted with valves G and H.
This seems to be just as handy as any
automatic moisture trap which would
have to be disconnected when the sam-
pling pipes were being blown out. The
valve } is used to close and protect the
machine when the pipes are being drained.

I would like to hear from any readers
who have any criticisms to offer or can
describe a better system.

Charles M. Rogers.

Detroit, Mich.

Using the Firm's Stationery

I recently visited a steam plant in
which were installed a couple of old slide-
valve and a Corliss engine about four
months old. The engineer in charge was
a pleasant chap and in the course of
our conversation related an experience
he recently had. He said: "I wanted a
complete indicating outfit, so 1 looked
over Pov ER and saw one advertised that
I liked. Here is a copy of the letter 1
wrote. the manufacturers on our letter-
head:

'Gentlemen: Please send me full
particulars and quote me cash price for
your indicating outfit as advertised in
Power. Include in your quotation a
planimeter of reliable make. I intend to
take the matter of purchase up with the
firm as soon as I have read up on your
instrument.

'Yours truly.

'John Doe.'

"Now, friend, here is the way the
company, an Eastern concern, treated my
letter. They wrote to a Western machin-
ery house to represent them in the sale
of an indicator to my firm. They in turn
sent a salesman who did not pome near
the engine room, but headed straight for
the office. He met the owner with, 'Good
morning; you are in the market for an
indicator and I've got the very one you
want.'

"The owner replied, 'No, young man,
we do not need a steam-engine indicator;
here is one we have had for years and it
has hardly ever been used,' to which the
salesman replied. 'Guess there's been a
mistake somewhere.'

"That indicator in the office, friend, is
an old McNaught and it has not been
used much."

We discussed advertising from an en-
gineer's point of view and before I ramc
away the engineer in charge had written
for another catalog on a plain sheet of
paper. I have since wondered how many
catalogs never come and how many man-
ufacturers miss sales to the engineers
who use the firm's stationery.

Paul Montague.

Seattle. Wash.

640

POWER

October 24, 1911

Die Stock

It sometimes happens that split dies
will not fit the die stocl<. To obviate this
trouble, I decided to make a die stock
to fit the dies. The accompanying illus-
tration shows its construction. The main

I could not put the new casting A on
the inside of the casting B, for when the
new crosshead came I found that the en-
gine company had changed the pattern,
making it so large that it came within A;
inch of touching A when flush with B.
I turned the casting down, leaving a thin

1

i

J ■ '!

Improved Die Stock

body /] is a brass casting and the ends
are threaded for 'i-inch pipe handles.
The dies are slipped into this, so that the
two 7/ 16-inch pins 6 will catch the half-
round slot on the dies and hold them in
place. Above this is the steel split ring
C and above this, a combined cap and
nut.

By screwing down the cap D on the
body A the split ring is compressed and
the dies are brought closer together.

A lip on the ring prevents the dies
from slipping out.

F. L. Stewart and H. L. Kohlberg.

Asarco, Durango, Mexico.

Repairing a Broken Engine
Casting

Some time ago the crosshead of a
9x 10-inch', high-speed engine broke while
running with about half a load. The en-
gine ran in oil and there is a packing box
in the position at the cylinder end of the
engine-bed casting containing the oil, be-
sides the packing box in the cylinder,
leaving a space of about 6 inches be-
tween the two.

In both illustrations, B represents a
part of the main casting of the engine
bed. The packing-box casting A was
originally put in as shown, the
right-hand side being the one next to
the crosshead. When the crosshead
broke, part of the casting remained on
the piston rod, and as the rod and piston
went hack it knocked the cylinder head
out and broke the casting A and the
flange £ off of the casting B.

As I cc'ild not make another casting
the size of A stay in, I filed off the broken
surface at E as best I could and ordered
the new casting sent with the outer rim
unfinished so I could turn it down to fit.

flange ], which could not make it any
thicker because the two packing boxes
came too close together. The piece P is
of wrought iron and of the same thick-
ness as the flange.

I put on a thin gasket at H, replaced
the two bolts U in the opposite way from
what they originally were and clamped

Hot Crosshead Pin

The crosshead pin of a 2200-horse-
power, vertical, cross-compound engine
ran hot for almost two weeks.

Before the trouble was located the ad-
justing wedge was loosened and by giv-
ing the pin plenty of oil it was made to
run for several days.

Then the pin was taken out and found
to be badly cut. It was turned off and
both brasses rebabbitted and scraped
to fit the pin, after which they were
replaced and a load put on the en-
gine.

After a few hours' run it began to heat
up again and get noisy. The brasses
were taken up after each run, but the
pin continued to run warm and wear away
the babbitt. The brasses were scraped
again and, when the load was put on, the
trouble was still there.

During all this time the pin was get-
ting all of the oil it needed; in fact, the
oil was fed in a stream.

This pin was lubricated by a telescope
oiler which consists of a pipe attached to
the crosshead and hollow pin.

Where the stationary pipe enters the
moving part on the crosshead the pipe
is bushed by a brass bushing which
must be a close fit.

The whole trouble was in this bushing,
which had become worn so that the oil

Where C^=TiNt Broke and How It Was Repaired

the flange -jp reasonably tight. It does
not leak oil. has been running over a
year and has given no trouble whatever.

If the casting B had been small I would
have gotten a new one, but as it was very
large it would have taken too much work
and time to have changed it.

E. V. Chap,man.

Decatur, 111.

worked up around the pipe instead of
going into the pin.

.•\ new hush was made and put in, and
the trouble was over.

This illustrates the importance of at
tending to little things about the power
plant.

Frederick L. Ray.

Louisville. Kv.

October 24, 1911

P O W E R

641

ir*%-.-

^.s

Condemns License Laws

H. J. Leiper, of Philadelphia, writing
in the September 12 issue of the license
laws of Philadelphia, calls attention to
a situation which seems almost incredible,
in that men who as a class are usually
considered very broad-minded, should
pass, or cause to be passed, laws as
despicable as the license laws of the
city in question. Why an engineer should
want to deprive another of the right to
earn a living I cannot understand.

I would like to see the constitutionality
of the Philadelphia license law tested in
the courts. I do not think that the courts
would uphold it because it virtually
makes an American citizen living out-
side the city a foreigner or an alien.

I believe that the American constitu-
tion says that each State or municipality
must extend equal rights to all Ameri-
can citizens, no matter where or in what
part of the Union they may reside, and
also that each State or municipality must
recognize the laws of other States. It
such is the case, a man who has a li-
cense to operate steam engines and boil-
ers in one State has a right to operate or
to receive a license to operate steam en-
gines or boilers in any other State or
municipality having a license law.

I understand that the Ohio, New York
and Massachusetts license laws all con-
tain a clause which provides that engi-
neers who are licensed by marine boards
or the license boards of any other State
or city, may receive licenses upon apply-
ing to the proper parties. In Ohio a
marine engineer must undergo the sta-
tionary examination in order to obtain a
stationary license, but there is no red
tape to go through and a man need not
ask favors of anyone.

License laws will not increase the en-
gineers' wages to any great extent nor
will they cause a scarcity of engineers,
because pay is a matter between em-
ployer and employee.

As to causing a scarcity of engineers,
when a man makes up his mind to get
a license he can gel one all right.

I think that the only way to settle the
license question is to make it a Federal
license law and take the whole thing out
of the hands of selfish schemers and put
it under the civil service; then unscrupu-
lous men cannot use the laws to further
their own ends and every man will have
an equal chance with the rest.

A A. Blanchard.

Oak Harbor, O.

Pump Trouble

I have not had the same trouble as
described in the September 19 issue by
Potblyn, "Pump Doctor." but I have been
up against something like it.

At this plant there is an outside-packed
tandem pump drawing water from a tank,
as shown in the accompanying figure;
the suction pipe is 2 inches in diameter.
The pipes shown at the top of the tank
indicate the drip returns froin steam-

Arr.n.nclment of Tank .nnd Slction
Pipe

cooking kettles: the tank is 4 feet square
and is covered with a loose iron cover.

If hot water only is coming from the
drips the pump will lift water no matter
how slowly it is running, but if some of
the drips are discharging steam the pump
has to be speeded up considerably to get
it to lift the water, although the tem-
perature of the tank water remains the
same as in the first case. There can be
f.o pressure of steam in the tank above
the water, as there arc holes in the side
where the drips enter and the cover is
a very loose fit. The temperature of
the water is never over 170 degrees at
the check valve,

I have been thinking since reading the
article above referred to, that possibly

the steam above the water and in con-
tact with the suction pipe might raise the
temperature a few degrees in the pipe
ami thus .;iake it a little more difficult
for the p.iiTip to handle the water, so I
tried an experiment. I got a piece of
sectional pipe covering and placed it
around the suction pipe inside the tank
above the water. Then 1 replaced the
cover, turned in a rush of steam, started
the pump, and away she went as good
as could be desired. Of course, I did not
leave the pipe covering on; I made an
outside connection for the suction near
the bottom of the tank. This will remedy
the trouble, and 1 thank Potblyn for put-
ting the idea into my head.

J. Ellethorn.
Toronto. Ont.

Massachusetts License Laws
and E.xaminers

I have carefully read the letters in
Power criticizing my letter which ap-
peared in the August I issue. Referring
to the criticisms from Massachusetts,
they are from men who have secured
their first-class license, and, therefore,
have no personal reason to complain with
the present conditions.

The letters are more in the nature ol
a personal mudslinging contest than an
intelligent discussion of a general sub-
ject, and they illustrate how much it is
possible for some men to write without
saying anything when the subject pre-
sents aspects antagonistic to their per-
sonal opinions; this latter is particularh
true of Mr. Ironside's letter in the
September 5 number.

He relates instances of malicious ac-
tions practised by some engineers. These
things are older than the license law.
and have no hearing on the subject.

I do not claim to have heard of all
the protests that have been made against
the Massachusetts license laws and ex-
aminers, but I have heard sufficient to
occupy all the space in Pou kr available
for discussion letters for several issues.
With this thought in mind, my letter of
August I was written in the hope ol
starting a campaign of clean agitation
by those who have justifiable grievances,
and there arc plenty of them. I thought
that sufficient pressure might be brought
to bear to cause an official investigation
into the abuse of authority practised by
some of the examiners on applicants for
license.

My letter was strictly general, both ir.
word and spirit, but some of the critical

642

POWER

October 24, 1911

replies are strictly personal. There are
some examiners who are fair-minded
men; there are chief engineers who do
all they can to educate and advance their
assistants, even recommending them for
higher positions, and there are assistant
engineers and firemen who, having failed
to secure the desired license, unjustly
ridicule the examiner, but these cases
prove the exception and not the rule. I
confess myself in error in that I failed
to note these exceptions in my first let-
ter, but with these exceptions I still hold
to the contents of that letter. When I
made the statement that some questions
made the chief engineers gaze dum-
founded, I had in mind three of the best
(irst-class engineers in the city of Spring-
field, Mass., and there are some others.

Mr. Smith seems to have the mistaken
idea that there are no uptodate chief
engineers in this part of the State, but I
believe we have some who could make
good even in Boston.

Mr. Smith speaks of visiting "Room
3" of the State house. An engineer
other than one holding a first-class li-
cense would stand about as much chance
of gaining admission to that room dur-
ing a business session as he would of
securing a personal interview with Presi-
dent Taft.

When an engineer anticipates making
a visit to the examiner he usually visits
other engineers, exchanging experiences
and asking questions, and he visits
plants where he can examine new or in-
teresting apparatus; he also does some
extra studying, but I fail to see how
these things indicate that a man is being
coached and crammed only for the sake
of getting a license, as Mr. Lyman says
in his letter.

The engineer referred to in my letter
of August 1, who had 14 years' experi-
ence, was turned down because he was
unfortunate in lacking the advantages of
an early education, and while thoroughlv
capable of taking charge of and operat-
ing boilers, he was not able to design and
build one.

Mr. Chadwick, in his letter of August
29, says, "that it is wrong to cease study-
ing after a license is secured." I heartily
agree with him. I subscribe to three
power-plant publications, two steam and
one electrical; I have a great number of
books and trade catalogs, and I read and
study them. I am also a member of an
engineers' organization, which takes an
■ active interest in its educational work,
and the watchword among my friends
and acquaintances in this business Is
"Learn more!"

Mr. Ironsides, in his letter of Septem-
ber 5, advocates making the examinations
more severe. I have heard that senti-
ment expressed before, but it was always
by first-class engineers. That the majority
of these men are indifferent to the in-
terests of their assistants and some even
opposed to them Is true. What stronger

evidence can one ask than the very at-
titude these engineers have assumed to-
ward the subject of my letter?

I have read with interest the letter on
"License Agitation in Rhode Island," by
Mr. Mclnis, in the September 5 issue,
and from experience I can verify the
truth of his statements regarding both
the conditions and wages In no-license
States. These conditions represent one
unreasonable extreme, but a law which
requires a man to design and erect a
plant in order to secure a license to op-
erate one represents the other unrea-
sonable extreme.

,1. A. Lew.

Greenfield. Mass.

Direction of Compressor
Rotation

In the August 10 issue it is asked if
there is any reason for running an air
compressor under. The answer states
that there Is none. If the question refers
to a straight-line, steam-driven machine,
I contend that running over is proper,
just the same as in other steam-engine
practice, as it takes power to turn the
heavy flywheel and valve gear, thereby
bringing the crossheads and bearings
down. Running under brings them up.
But in power-driven compressors it is
different. They should be run under as
the power begins at the main shaft; this
brings the bearings and crossheads down
and running over brings them up.

A. E. Peterson.

Pocatello, Idaho.

Air and Steam Bound Pump

I read with interest Mr. Watson's arti-
cle about that troublesome pump at the
Maddern mills. I had a similar experi-
ence with a pump in a plant where I
was employed. The heater was con-
nected up in a manner similar to Mr.
Clark's heater, excepting that there was
no float valve to keep the water level,
which was controlled by a globe valve
in the cold-water supply.

The cold-water pipe entered the heater
at the same end as the bleeder exhaust
from the engine. Back pressure \</as car-
ried on the engine for the heating sys-
tem and it quite naturally cau?ed some
steam to go to the heater and heat the
feed water to 212 degrees.

The feed pump would run smoothly
just so long as no cold water was turned
into the heater; but, as soon as cold water
was turned on, the pump would begin to
pound and show signs of getting air or
steam bound.

I finally decided, as "Pump Doctor" did,
that the cold water caused a vapor in
the pump-supply pipe. I ran a vent pipe
from the top of the heater through the
roof of the boiler room, which stopped
the trouble.

A. St..\ley.

.loliet, in.

Failure of Mixed Pressure
lurbine Installation

In the issue of September 26 is an arti-
cle entitled "Failure of Mixed Pressure
Turbine Installation," by C. A. Tupper,
which is misleading.

In the article it is stated that the tur-
bine manufacturers were very much in-
terested in this particular plant and that
after an apparently careful examination
of the operating conditions they all but
one refused to put In a proposal, stat-
ing that the scheme was not commercial-
ly feasible. It is very hard to under-
stand how such a statement could be
made when referring to two years back,
it is noted that a large number of installa-
tions were in successful commercial op-
eration, none of which was essentially
different from the plant mentioned In Mr.
Tupper's article.

In the installation referred to some
10,000 pounds of exhaust steam per hour
are wasted and It is difficult to under-
stand how it can be said that this avail-
able amount of exhaust energy had better
be abandoned.

The hoisting engine mentioned has an
exhaust of "cyclonic violence." This is
no way objectionable as regards the fur-
ther use of steam in a constantly running
engine if proper means to handle this
exhaust be employed. It is quite true
that the hoist shuts down for periods
as long as half an hour, an hour, or even
more. This can readily be taken care of
by the use of a suitable mixed-flow tur-
bine, which allows the use of some high-
pressure steam when the low-pressure
steam is deficient or runs entirely on
boiler steam when the low-pressure steam
supply is exhausted. Mixed-pressure tur-
bines can be made to have, when running
en high-pressure steam, as good a steam
economy as straight high-pressure tur-
bines. This is a question of design.

Mr. Tupper's article implies that steam
regenerators cannot equalize the exhaust
from powerful hoisting engines without
imposing on the hoisting engines undue
back pressure (in the case referred to,
10 pounds gage).

There are in operation some 500 or 600
regenerators, some of which have been
in operation for the last seven or eight
years, which handle intermittent fluxes
of steam compared to which the exhaust
of the engine referred to is but a trifle.
If 5 pounds variation of pressure be al-
lowed in a properly designed regen-
erator at the plant referred to I which Is
far in excess of steam-regenerator prac-
tice), a steam turbine could use the ex-
haust steam discharged by the hoisting
engine without any appreciable amount
being wasted.

The failure of the plant (which was
predicted by the writer) is entirely due
to the poor design of the steam regen-
erator.

October 24, 1911

POWER

The regenerator used at the mines re-
ferred to was described and discussed
in Power of November 8, 1910, by C. H.
Smoot, and the results of its operation
foreseen. The method of heat absorption
in the device employed is the same as in
the Rateau regenerators; that is to say,
is obtained by mixing water and steam,
the flow of steam in both cases being
used to promote circulation of water, but
the design of the apparatus is such that
instead of using a light pressure to dis-
place large masses of water, a consider-
able pressure is employed to displace
small amounts of water. For the ex-
tremely large zone of condensation of
the Rateau machine is substituted a re-
stricted zone, which is so disposed as
.to oblige the steam to force its way
through a head of water some 7 feet in
hight.

The writer agrees with Mr. Tupper that
under the circumstances the low-pressure
plant not only "would appear" but has
resulted in an actual loss. It is some-
what late to express any doubt as to the
commercial value of the use of mixed-
flow turbine plants operating on the ex-
haust of hoisting engines.

There are quite a number of mines
abroad where the mixed-pressure tur-
bines installed as stated drive electric
generators, high-pressure centrifugal
compressors or pumps, and on which
the mines rely exclusively for their op-
eration. These plants have made large
savings for their owners.

In this country, mine owners are
rapidly commencing to realize that it is
bad policy to waste the exhaust steam
from their hoisting engines; several
plants are now in operation or ready to
operate. In such installations the use
of steam regenerators having large heat-
storage capacity and so designed as to
be able to absorb excess steam prac-
tically instantaneously must be provided.

The use of mixed-pressure turbines hav-
ing high efficiencies when running on
boiler steam is necessary when complete
shutdowns of the hoisting engines are to
be expected. Straight low-pressure tur-
bines cannot be recommended in any
plant where the turbine is to run on
boiler steam expanded through reducing
valves for any length of lime. In other
words, 40 pounds of steam never should
be used to produce a kilowatt-hour when
20 pounds can do as much.

I do not agree with the statement that
"the facts were soon spread abroad and
have caused unwarranted injury to the
legitimate claims of low-pressure tur-
bines in the extensive district affected,
for the reason that the power-using pub-
lic does not take into account the cir-
cumstances that this unit was installed
In a place for which it was not adapted."
The facts well spread abroad are that
the plant was entirely experimental for
the people who undertook to place it in
operation, and that no steam regenerator

of the design used was ever built before.
The mine owners were fully informed of
all this, and the writer was told that a
bond had been required for protection
against patent suits and the performance
of the plant. The plant failed, due en-
tirely to the regenerator, which is so
designed that the rate of steam absorp-
tion is inadequate.

The writer's contention can readily be
disproved, if wrong, as engineers of great
ability have tested the regenerator care-
fully. The publication of any one of
these tests will, I think, realize the de-
sire of Mr. Tupper, which is to have the
mining engineers fully informed.

On the other hand, as regards the ad-
visability of such installations, I refer
to all the plants my company has placed
in operation in this country, some of
which handle the exhaust steam of re-
versing mill engines at the rate of over
350,000 pounds per hour.

L. Battl',

President, Rateau Steam Regenerator
Company.

New York City.

Loo.se Crank Pin

In the September 5 issue, Mr. Fitts
cannot understand why the loose crank
pin caused the centrifugal oiler to un-
screw from the pin when the pin turns
in the disk. He does not state whether
the engine is a right-hand or left-hand,
but that the pin turns to the left, or

Fic. I. Right-hand Fig. 2. Left-ha.nd
Engine Engine

counterclockwise, and at the same time
the oiler unscrews.

I believe there is some mistake here,
assuming it to be a right-hand engine
and running over as he says it does.
When the crank-pin brasses grip the pin
it turns to the right in the disk, or
clockwise, as shown in Fig. I. This would
cause the oiler to unscrew if it had a
right-hand thread.

If he has a left-hand engine the pin
turns to the left, or counterclockwise, as
shown in Fig. 2. As he says it does, this
would cause the right-hand threaded oiler
to screw in tighter as the pin turns to the
left, while in the first case the pin turns
to the right with regard to the oiler.

I believe his mistake is in assuming
the pin to turn to the left when if actually
does turn to the right and that he has a
right-hand engine. It would be interest-
ing to know if this is the case.

J. C. Hawkins.

Hyattsvillc. Md.

Why Central Station Catches
Isolated Plant Business

I note in your September 26 issue,
page 477, an article entitled, "Why Cen-
tral Stations Catch Isolated-plant Busi-
ness," by H. D. Jackson. There is much
truth in what Mr. Jackson sets forth as
to the reasons for central stations get-
ting the business which he claims is
justly due to be handled by the isolated
plant. The central stations do have
solicitors who are expert engineers and
know rather intimately the costs of power
both as produced by the central station
and by the isolated plant, but in suggest-
ing that these solicitors in general de-
liberately mislead the prospective cus-
tomer as to his costs from the use of the
isolated plant I think he is wrong. Not
all solicitors are paragons and some of
them make misrepresentations. I do say,
however, that the solicitors of the central
stations grade up in integrity and in
ability with men in any branch of en-
deavor, and that it is not the policy of
the central station (broadly speaking)
to get business on any basis except that
of strict integrity.

In soliciting the business of the iso-
lated plant frequently the operator or
owner has not taken into account all of
the expenses and it is a perfectly legiti-
mate practice to call attention to these
overlooked items. Frequently the iso-
lated plant could make changes and effect
economies which in themselves would
reduce costs to the same level of ser-
vice purchased from the central station,
but I am unable to see that it is the
solicitor's duty to teach the isolated-plant
man how to run his business nor that it
is sharp practice to sell his goods and
thereby save the consumer on his power
bill. This same thing is done in all lines
of business, and the salesman who
shows how to save money by using his
firm's product (although the use of this
product may not he e 'irely responsible
for the saving) is a benefactor.

One fact in the central-station proposi-
tion which must not be overlooked is that
unless they make good on the savings ef-
fected the business will be lost. That
they are not losing all of this business
shows that they are not failing to make
good.

If. however, the engineer in charge of
the isolated plant were on the job he
could frequently match the costs of cen-
tral-station service, but that he is not
alive and allows the central station to
underbid the costs of isniatcd-planf op-
eration is certainly no fault of the cen-
tral station. Then, too. there arc cases
of coal cartage, small-size installation
and other features incident to the iso-
lated plant which make it inevitable that
service can be purchased cheaper than it
could possibly be furnished by the iso-
lated plant.

644

P O \V E R

October 24, 1911

To the extent that they induce engi-
neers of isolated plants to keep definite
records and ascertain not only what they
are doing, but enable them to success-
fully reduce their costs, articles as that
above referred to will be productive of
great good. But it does not appear to
the writer that it is necessary to impute
any dishonesty to the central-station
solicitor in order to make out a case.

Whether service will be supplied by
central station or isolated plant will ulti-
mately be decided by the economics of
the case rather than by any appeal to
prejudice or sympathy.

R. L. Ellis.

Selma, Ala.

Sand for Hot Boxes

In the August 29 issue of Power ap-
peared an editorial, "Sand for Hot
Boxes," in which the statement is made
that on many ocean steamers a box of
sand is a part of the engineer's emer-
gency outfit. I have been a marine en-
gineer for the past 30 years and I have
never seen a box of sand on shipboard
and I hope that I never shall. When an
engineer is running marine journals the
only sand he needs should be in his own
makeup.

I would like to hear from engineers
who have used sand and in what class of
steam vessels.

I also noticed in a later issue an arti-
cle on refrigeration which stated that in
order to get the best results the con-
denser and suction pressure must be car-
ried as low as possible.

I get the best results by carrying my
condenser pressure as low and my suc-
tion just as high as I can and get the
temperature required; the higher the suc-
tion pressure the more ammonia the ma-
chine will handle and less power is used
to do the work.

Frank H. Coroner.

Niantic. R. I.

Value of CC)_. Recorder

It is not my intention to criticize the
previous writers on the above subject,
but when a man of E. A. Uehling's capa-
city makes two conflicting statements, as
he did in the June 13 issue, where he
says, "in all cases high or low CO.. means
high or low efficiency." and again in the
issue of .August 15, where he says, "since
COi by itself is not claimed to be. and in
the nature of things cannot be, a measure
of efficiency," etc., it seems to me as
though Mr. Uehling should write and ex-
plain clearly which of his two statements
he is ready to back up and why.

That the CO recorder is of any value
in measuring furnace efficiency is a ques-
tion to which no definite answer has as
yet been given in the articles that have
appeared in Power.

I agree with Mr. Uehling that "in all

cases high or low CO; means high or low
efficiency," for the higher the percentage
of CO; the greater the number of avail-
able heat units to be transferred to the
water within the boiler. If this tends to
efficiency then a high percentage of CO^
means a high efficiency. If in all cases
high or low CO- means high or low effi-
ciency, why is not the C0= recorder of
any value in measuring furnace effi-
ciency?

A combined CO; and draft recorder,
properly installed to draw an average
sample from the gases at a point where
they are leaving the heating surface of
the boiler, will certainly be of value in
measuring furnace efficiency.

For the sample I w-ould use a J j -inch
pipe, capped at the end inserted into the
path of the gases and having nj-inch
holes drilled about 3 inches apart, the
pipe being extended fully across the path
of the gases, .'^s the percentage of CO;
is to a great extent influenced by the
draft, it demands that a draft recorder
be installed with the CO.- recorder. A
combination apparatus if properly cared
for will show on the chart the percent-
age of perfect combustion, and will show
the draft employed at the time the CO::
was recorded; a study of the chart will
show just in what position to set the
damper to obtain a draft through the bed
of fuel that will give the greatest per-
centage of COl.

It is necessary to know whether enough
excess air is being heated to keep a dupli-
cate furnace running to its full capacity.
If the percentage of CO; is as low as 7
per cent., enough excess air is being
heated to keep a duplicate plant running,
and between 25 and 30 per cent, of the
heat units is lost in heating air from at-
mospheric temperature to the tempera-
ture of the leaving flue gases.

In locating these troubles and finding
their remedies the CO; recorder is prac-
tically useless, as it is limited to CO2,
while it would be necessary to determine
O and CO. The CO; recorder is too slow
for this work; it makes an analysis only
once every four or five minutes, when
it may be necessary to analyze a sample
every minute.

To measure and locate air leakage two
gas samples must be taken from two
different points in the setting simultane-
ously; then make a separate analysis.
Here again the CO; recorder would be
useless as it is not practical to connect
it anywhere but in the breeching at the
point where the gases leave the heating
surface of the boiler.

In working for higher efficiency with
the gas-analysis instrument every ob-
served furnace condition must be noted
at the time each CO; determination is
made; every such condition has its cause
for being so and any change in that con-
dition will effect an increase or decrease
in the percentage of CO; or the efficiency.
If, for instance, there is a bare spot

in the fire about 2 feet square, take a
sample of gas, analyze it. Then cover the
spot with fuel and analyze another
sample, and invariably a higher CO;
reading from the last than from the first
sample will be obtained. By applying
the draft gage, flue-gas thermometer and
flue-gas analysis instrument diligently to
the furnaces the indicator on the CO.
recorder will point to the percentage of
CO; that means highest efficiency, and
the coal bill will be reduced. Then make
CO; recorder keep watch over the im-
proved furnace conditions that they may
not gradually get back to the old point
of inefficiency.

R. S. WiLHEL.V.

Indianapolis. Ind.

Gage Glasses

In the September 19 issue, Mr. Bond
asks me to explain more fully about put-
ting in gage-glass washers.

The accompanying sketch will do that
better than words. The washer is for
the purpose of preventing the rubber
gasket sticking to the nut. If the washer

W.\snER IX Packing Nut

v;ere placed below the gasket, the rubber
would stick to the nut and it could not
be tightened without danger of turning
the glass in the opposite stuffing nut,
which would tend to break the gage
glass.

George R. Willia.ms.
Findlay. O.

Noiseless Corliss Valve Gear

My method of lessening the noise of
• the valve gear being different from either
.Mr. McGahey's or Mr. Mistele's in the
.August 15 and September 19 issues, re-
spectively. I will give it herewith.

Noting where the steel tailpiece came
in contact with the knockoff-cam collar,
I drilled a \<-inch hole 's inch deep at
that point and inserted a plug, which has
been renewed but once in 15 months.
W. A. Watson.

Marion, O.

October 24. 1911

POWER

645

Issued Weekly by the

Hill Publishing Company

.l-HN .>i. Hill, I'n-s. aiul Treac. Bob"t McKEAN,Sec'y.

50.') Fearl Street, New York.

122 South Mlchli;*!! Boulevard, Clilcaso.

6 BouTerip Stn-vt, Lnndou, E. C
i;titerden Linden 71— Berlin, N. \V. 7.

Correspondence suitable for the col-
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Contents I

A < onev Island I'MWcr I'lanI

1'as.slD;; ol Another \'eteraii

Yahie of EnL'lne Uoom ln.spocll"n

Slressesi In Locomotive Boilers

Caii.ies and rrevenlion of Corrosion

D^-veloimienls In Prime Movers

on Can Stand

Induction Motor Uepalis

The Cnre of III! Enclnea

America's I'ndevelopi'd Pent Bo>!'<

A Looped Kliiernm and l.ale lunillon...

Oawdene In iln' Crank Cas^-

I'racllcal I..-iii-r«:

rnhalnnind Fields ... .Sn. lion Lift
of p.nni.»....l.n|. S..,>ni l-ra. lured
.... Presnuie in Pump lilscli.inte
I'Ipe. . . .Biirnlne Puel nil... .Ma-
chine for Clennlnc Oily Wnslc . . .
Connecllni; fp CO. Itecorders. . . .
I"lni.' Ilie I'lrm'!! Stationery ... .Iile
Slock. . . Ui'pairlnL' a Uroki-n Knglne
Castlnu. . . .Iloi CnMnliead Pln...t;:i7

lilKOUfwIon L'il'r«:

Condemn" Llc.n«<' 1ji»« .... Pump
Trouble .... Mn-vniliUHcin l.l.en«e
Lawn and Kxamln-Ts .... IHreiilon

of Comprex'ior llolnllon \li- and

Slonm Itoond Pump . . . . Pallure of
Mixed Preaaiire Turbine Inolnllnllon
. . . , |,on-u' Crank Pin. . . .Why Cen-
Irnl SInilon cnlcheo Inolslod Plnnf
ttu«lne««. . . Snnd for Hot Hoxe«. ...
Value of cr>, fterorder . . . . Onse
• ilanwd. . . . Nol«elewi ('orllM VnlTe
<;piir «■»!

EdllorlaU O'l.".

llenlInK an Addition to n Karlory

Water Hammer In IFealInK S.TBlem

Venlllatliin of Rurklnetinm I'alare

Vapor I'nmp Trouble"

Pipe Flanges

The question of suitable flanges for
steam piping is of tfie utmost importance.
In a recent editorial attention was called
to the fact that of all parts of the pipe
line the fittings 'must be the strongest.
This is necessary on account of the
strains thrown upon them by the e.\-
pansion and contraction of the piping.

For pressures of 250 pounds or more,
extra-heavy wrought-steel flanges \ elded
on make the best construction, provided
the weld is properly made so that the
flange becomes a part of the pipe itself.
One is never certain, however, that this
has been done, and care must be used
in the selection of this process for this
reason. There are also several other
methods of applying flanges that have
been quite satisfactory.

For sizes up to and including three
•ind a half inches it is customary to use
threaded flanges and screw them upon
the pipe. This is also a common prac-
tice for larger sizes when the pressure
does not exceed one hundred and twenty-
five pounds. If the steam is not super-
heated, cast-iron flanges will answer very
well up to two hundred and fifty pounds,
although for the higher pressures the
greater safety resulting from the use
of ferrosteel or forged steel no doubt
fully warrants the slightly increased cost
of the latter materials.

In order to insure a good job of piping,
it is imperative that the flanges be faced
off after they have been put on the pipe
so that they will be true with the pipe
and have a good contact when put to-
gether. A cut should be taken the en-
tire width of the flange and, if it is
screwed on, the end of the pipe should
protude enough to allow its being faced
off flush with the face of the flange. This
will then give the gasket a bearing upon
the end of the pipe as well as on the
flange.

Nearly all manufacturers specify in
their catalogs that companion flanges will
he furnished with smooth faces unless
otherwise specified. Whether or not this
means that they recommend plain-faced
flanges as preferable lo all others is not
stated.

In this particular there are several
types of flanges, such as the above men-
tioned, namely: plain, male and female,
tongue and groove, raised, and flanges
v'ith a calking recess. In some plants
the plain or smooth face is preferred for

all pressures and it is universally used
for low-pressure work because of the
ease WMth which repairs can be made.
Others use exclusively a flange having a
raised face about one-thirty-second inch
high, extending the full width inside the
bolt holes. This projection is smooth
tool finished and is particularly adaptable
when using metallic gaskets. Probably
the safest kind is the male and female
which practically eliminates all danger
from gaskets blowing out. This type is
also more commonly used under high
pressures than any of the others.

Multiplicity of Head.s

Experience has demonstrated that con-
centration is one of the remedies for use-
less waste. Years ago the scheme of
appointing heads over the several depart-
inents was adopted. This has always
been successful as the heads of concerns
are not bothered with details, but can
turn their attention to outlining the gen-
eral policy.

As an illustration, many large manu-
facturing concerns have several separate
steam plants, each in charge of a running
engineer responsible to a chief engineer,
who makes his report to the agent of the
works. Holding the several acting engi-
neers responsible to a chief engineer is
productive of economic operation. Noth-
ing demoralizes the engine-room force
so thoroughly as to have several heads
over them; the men are then responsible
to no one in particular.

In a certain manufacturing coiripany
there are seven separate steam plants.
Fach has its chief engineer who has com-
plete control of his plant and is responsi-
ble to no particular head. Kach one does
his work to suit hiinscif, and if he finds
a metho.d of reducing operating expenses
he keeps it to himself rather than in-
form his associates; as a result the com-
pany suffers a loss.

What is everybody's business is no-
body's business, and this truism is evi-
dent in the case cited. If a chief engi-
neer were in charge of all of these steam
plants the improved methods adopted in
one would be applied to all and the com-
pany would be benefited. Further, each
acting chief would try to make a good
showing with the chief, and, although
there might be rivalry, it would, on the
whole, be beneficial.

.Jealousy among engineers is hannful.
It causes them lo become selfish and self-
centered and, what is worse, they lose

646

POWER

October 24, 1911

sight of ihe fact that they are supposed
to be working for the best interests of
the company. When there is no central
head there is no restraining influence over
jealous subordinates and the work is not
systematically performed.

The chief engineers of large establish-
ments are usually men who have e.v-
ecutive ability as well as engineering ex-
perience. They know how to prevent dis-
cord, and they aim to promote such good
will among the men that they will all
work together for the best interests of
their company.

Purchase Coal by Specification

Someone has said that the intelligent
farmer shows better business judgment in
the purchase of fertilizer than most man-
ufacturers in buying coal, for the farmer
insists upon a chemical analysis of his
proposed purchase. Until recently coal
has been bought in a most haphazard
manner, on the recommendation of the
dealer, on the reputation of the mine or
perhaps on the supposition that the min-
ing district from which it came could
furnish only coal of superior quality.
Under this system or lack of it, if the
purchaser found fault he was usually
assured that the quality of the coal was
equal to that of former days or years
for it came from the same mine and
must be good because the mine had es-
tabltshed a reputation which must be
maintained. Purchasers did not take ad-
vantage of the competition which usual-
ly exists when a number of dealers are
asked to bid on the price of a year's
supply, for they were shy of contractors
and dealers whom they did not know,
because, though each might claim that
his coal w-as as good as the best, there
was no standard for settlement if the
fuel delivered proved unsatisfactory.

Millions of tons of fuel are bought
every year upon terms that would be con-
sidered ridiculous if the commodity trans-
ferred were scrap iron or paving stones.
Where the products of mines other than
coal are sold in open market or by private
sale the price paid is based on chemical
analysis. This is true of coal to a limited
degree only but the number o'f yearly
contracts for coal based on its heat value
is rapidly increasing, for both dealer and
consumer are beginning to realize the
advantage of having a definite under-
standing regarding the quality of the
fuel delivered just as would be the case
if the contract was for hydraulic cement
or oak-tanned sole leather.

When a dealer is asked to specify the
quality of coal he proposes to furnish
he is placed on equality w^th all other
dealers and strict competition decides the
question of what coal shall be used.
Local conditions often cause a variation
in the quality of coal from a certain
mine; more care in rejecting slate is ex-
ercised at one time than another. The

mining companies are responsible for
this, but the sale of the output of the
mine on the basis of its quality will
stimulate the mine owner to furnish the
best available product. With the utmost
care, however, there will be some varia-
tion in the quality and no contract wil!
be satisfactory to either dealer or con-
sumer that fails to recognize and make
provision in an equitable degree for this
variation. A contract which fixes the
price for a certain heat-unit content with
deductions for inferior and bonuses for
superior quality will seldom fail to sat-
isfy all concerned in the transaction.

Coal is burned for the purpose of
utilizing the heat content. It is the com-
bustible that is wanted and it is that por-
tion of the combustible that can be burned
in the furnace that should be meas-
ured and for which payment should be
made. That fuel which will give the most
heat, all things considered, for each dol-
lar spent, is the fuel that will produce a
horsepower-hour at the lowest price.
With equitable deductions for the hand-
ling of extra bulk of coal and ash with
a low fusing temperature, making clink-
ers which complicate the firing problem,
and with bonuses on excess of heat con-
tent above contract specifications and a
nonclinkering ash, an entirely satisfac-
tory arrangement for both parties should
exist.

If coal is purchased under such speci-
fications, the buyer gets what he buys
and pays only for what he gets.

Indicate, Register and Record

Does a steam gage indicate or register
or record the pressure in a boiler? With
regard to the gage it would be perhaps
most natural to say that it "shows" or
"indicates," but we say of a thermom-
eter that it "registers" such and such a
temperature, when it does nothing more
than to indicate or show it, and there is
warrant both in the dictionary and in
usage for saying that the clock "records"
the passing hours.

Does an indicator indicate or register
or record what goes on in the cylinder
during the stroke? If it does all three,
in what does each consist?

By usage and common understanding
the word indicate, as applied to measur-
ing apparatus, is restricted to the momen-
tary indication or showing of the ap-
paratus, without any reference to the
marking down, registration or preserva-
tion of any record of this indication for
future reference or for comparison with
other indications. The hight of the pencil
of a steam-engine indicator "indicates"
the pressure beneath its piston at the in-
stant. By the marks which it makes up-
on the paper the pencil "records" the
pressure at each point of the stroke.
The record' may "indicate" that the
valves are late or early, etc.

To "record" has come quite generally

to involve the making of a permanent
record. Thus we have the recording
pressure gage which draws a record or
diagram showing the pressure existing
at any time of the day. This gage prop-
erly "records." The ordinary gage only
indicates; but how frequently one reads
that "at the time of the explosion the
steam gage 'recorded' one hundred
pounds," etc. In CO:: apparatus we have
the Orsat which enables us to determine
the COj in a given sample, the instru-
ments of the Econometer class, such as
the Hays analyzer, which have an index
"indicating" the percentage of CO. pass-
ing at the moment, and those that, like
the Uehling, Sarco, etc., "record" these
percentages upon a diagram which may
be preserved for reference and compari-
son.

The word of most uncertain use is
register. Although its derivation (re =
back, gcro = to carry, whence the Latin
regesta = records) and our use of it In
politics, business and law all imply a
marking down, a record, we have also
the frequent use of it recognized by all
the dictionaries, to signify simply indi-
cation, as when the thermometer "regis-
ters" 90 in the shade, the steam gage
"registers" 100 pounds, etc.

There is another class of measuring
apparatus which does more than indi-
cate but does not record. The counter,
for instance, which registers the strokes
of a pumping engine, tells how many
strokes the engine has made in a given
time but does not furnish a record of
how the making of these strokes was dis-
tributed. A gas meter registers the num-
ber of cubic feet of gas which pass
through it, but does not tell whether the
use was uniform or variable nor what
the rate of flow was at a given time.
One would hardly allude to the counter
as a meter, -nor to the meter as a counter,
but both do register.

On the face of a Venturi water meter
are three dials illustrating the three op-
erations referred to. First, there is a
hand or index which points to the num-
ber of gallons or cubic feet which are
flowing at that instant through the meter
per unit of time. It indicates the momen-
tary rate of flon'. Then there is a counter
which registers the total number of gal-
lons or of cubic feet which have passed
through the meter. Then there is a pen
which records upon a chart rotated by
clockwork the rate of flow for each in-
stant of the day.

Would it not be well for engineers
and writers upon engineering subjects
to agree upon some such restriction of
the application of these loosely employed
tenns ?

It is reported that a coalfield having
nearly 100.000.000 tons has recently been
discovered in Leinster, Ireland, and that
its quality is equal to that of the best
Welsh steam coal.

October 24. 1911

POWER

Ties of General Interest

^ horsepower

Horsepower of F.n^'me

An indicator pencil has a vertical
movement of one inch, which represents
a pressure of 00 pounds. The length of
the stroke of the engine is 20 inches; it
makes 90 revolutions per minute, and the
piston is 10 inches in diameter; what is
the horsepower developed ?

J. P. L.
If the average hight of the pencil
movement was 1 inch, it would repre-
sent a mean effective pressure on the
piston of 60 pounds per square inch. A
common forrnula for the horsepower of
a steam engine is
PAS
33.000
in which

P = Mean effective pressure against

the piston;
A = Area of the piston in square

inches;
S = Speed of the piston travel in
feet per minute.
Substituting the known values in the
equation and solving,

6o X 78.54 X .-^oo o , .

— - ~ = 42 .84 horse f>oucr

33.000

Cutoff atid Number of
Expansions

If the cutoff on the high-pressure cyl-
inder of a compound engine occurs at
quarter stroke and that on the low at
one-third, how many expansions will
there be in both cylinders?

C. N. E.

The number of expansions in a com-
pound engine is the product of the num-
ber of expansions in the high-pressure
cylinder and the cylinder ratio. With 4
expansions in the high-pressure cylinder
and a cylinder ratio of 4 — that is, the
low-pressure cylinder having 4 times the
volume of the high — the number of ex-
pansions would be 16. The cutoff on
the low-pressure cylinder does not af-
fect the number of expansions but is
used to distribute the load between the
cylinders.

Cruti^rade and Vahrcnheit T/wr-
tnoiiieter Scak

What is the difference between Fahren-
heit and Centigrade thermometers?

C. F. S.

On the Fahrenheit scale the space be-
tween the freezing and the boiling points
is divided into 180 parts or degrees, and
on the Centigrade into 100. Therefore, a

Questions are^

not answered unless

accompanied by theu

name and address of the

inquirer. This page is

for you when stuck-

degree Centigrade is 9/5 of a degree
Fahrenheit. To convert Centigrade read-
ings into Fahrenheit, multiply the read-
ing by 9 5 and add 32 because the zero
of the Centigrade is equivalent to 32
Fahrenheit. To convert Fahrenheit into
Centigrade, subtract 32 from the read-
ing and multiply the remainder by 5 9.

/y/if///" of Pump IJft

If 80 pounds steam pressure in a pump

cylinder will force water to a hight of

l.'^O feet, how high will it be forced by

pressures of 90 and 100 pounds re-

f pectively ?

H. P. L.

Neglecting the pump friction which

would be proportionally less for the

higher pressure, 90 pounds pressure

would raise the water

90 X 150 .. , ,
'— ^~= iOS.75 jeet

and 100 pounds

100 X I. so
80

= 198.75 feet

Steiiin iind IVater Tempeniture
If 25 pounds of steam at atmospheric
pressure were mixed in a barrel with
100 pounds of water at the boiling point,
how much would the temperature of the
water be raised ?

S. W. T.
Steam at atinospheric pressure having
the same temperature as the water could
not give up any of its heal and would
rise to the top of the water and pass off
as steam.

CiipOiitv of Cetitrifu{r(i/ Pumps

How many cubic feel of water will
be discharged per minute through a 9-
inch pipe by a centrifugal pump 36
inches in diameter running .300 revolu-
tions per minute and against a head of
90 fecf.'

C. P. C.

The head against which a centrifugal
pump will discharge depends on the
linear velocity of the lips of the blades.
At 300 revolutions per minute the tips

of the blades of a 3l5-inch impeller would
have a velocity of 47 feet per second
and with an efficiency of 100 per cent,
would impart this velocity to. the water,
which is equivalent to the velocity that
would be acquired by a body falling
through a hight of approximately 34 feet.
To rise to any hight the water must
leave the pump with a velocity equal to
that which would be acquired by falling
through the same hight; therefore a 36-
inch impeller nmning at 300 revolutions
per minute would raise water only to a
hight of 34 feet. To raise it to 90 feet
the velocity would have to be 76 feet
per second, which would require 400
revolutions per minute and an efficiency
of 100 per cerit.

C/hiiiirinir Le Machines

If while running one of two ammonia
compressors it is desired to change over
to the other machine, how should it be
done ?

C. I. M.

Warm the steam cylinder in the usual
way and when ready open the stop
\alves in both the suction and discharge
pipes. Bring the machine slowly up to
speed and reduce the speed on the other;
with it running slowly, close the suction-
pipe stop valve and then the one on the
discharge pipe. A compressor should
not be either started or stopped with
the discharge-pipe stop valve closed.

Factor of P.vaporation

What is the factor of evaporation?
W. F. E.

The factor of evaporation is the num-
ber by which the observed evaporation is
multiplied in order to convert it to the
equivalent of evaporation of feed water
at 212 degrees into steam at atmospheric
pressure. To evaporate I pound of water
imder these conditions requires the ex-
penditure of 970.4 heat units. For any
other conditions the factor may be found
by subtracting the total heat above 32
degrees in I pound of feed water from
the total heat in I pound of the steam
and dividing the remainder by 970.4.
With feed water at IS5 degrees made in-
to steam of l.'.O pounds pressure the
factor of evaporation is

1195 — iJ.'Sg

— 2:2 i! — i- 9 1.073

970.4

If 9 pounds of water were evaporated

per pound of fuel under the conditions

given, the equivalent evaporation fiom

and at 212 would be

9 X 1.073 - 9.657 pounds

POWER

October 24, 1911

Heating an Addition to a

Factory

By W. H. Wakeman

The original part of a certain factory
was but one story high, and quite long in
order to secure the required floor space.
A pair of tubular boilers were installed
for power and heating purposes, and an
indirect system of heating was in use.
The water of condensation from the coils
of steam pipes, around which air was
circulated by a fan, flowed to the receiver
nearest the boilers, and was used as
feed water which was handled by a pump
standing on the same base.

Later, a two-story addition was built
at the end of this factory farthest from
the boilers. The indirect-heating system

jections to the ordinary method of return-
ing hot water by gravity to the receiver
pro\ided for this purpose.

Steam from the boilers is delivered to
the reducing valve R and is reduced to
about 5 pounds pressure. The main sup-
ply pipe A is carried on suitable hangers
overhead in the factory where it does
not interfere with anything else. Water

through pipe E into the main receiver F
and it is returned to the boilers through
the feed pipe G. Steam to operate this
pump is delivered through pipe P and is
exhausted into the heating system through
an e.xhaust pipe, not shown.

This arrangement admits of heating the
two-story addition when the main one-
story building is not in use, which is a
desirable feature in this case. These two
pumps and receivers operate automatical-
ly in connection with each other, keeping
the entire system free from water at all
times.

Water Hammer in Heating
System
By C. B. Hudson
Some months ago I became interested
in the peculiar action of a steam-heating
plant, which was laid out as shown in
Fig. 1, and consisted of a vertical fire-
tube boiler 36 inches in diameter with 96
two-inch tubes 5 feet long.

The boiler, which was installed second-
hand, is located in the basement and
furnishes steam for 1000 square feet of
radiation, part of which consists of pipe

^&ij

rd^

^iW^

y;<m^<^<yMmmW//.

Section throi'ch Building Showing Piping

already in use was not sufficient for this
extra service, and it was found inex-
pedient to increase its capacity. There
was no cellar under the long building
and owing to the nature of the ground it
was not advisable to build one. .Also,
there were several doors in the sides of
this building; hence the return pipe could
not be carried above the floor, as it would
cross the doorways. The following plan
was recommended to overcome these ob-

from this pipe drains into the secondary
receiver, leaving dry steam for the radi-
ators on both floors. The water of con-
densation returns through the single-pipe
system and flows by gravity into the re-
ceiver C.

Steam at boiler pressure is supplied
through the small pipe D to operate the
secondary receiver pump, which exhausts
through separator S into the heating sys-
tem. This pump discharges hot water

coils and the remainder of radiators
which are located on two floors.

Connections were made to the boiler as
shown in Fig. 1. Steam was taken from
the top head through a 1 '4-inch pipe
and stop valve A.

The 1' 1-inch pipe led into a tee in
the 3-inch main, which supplied steam
to all radiators and coils. Connection B
is a drip for draining the pocket formed
in the 1 ' i-inch pipe.

October 24, 1911

P O W E R

649

As the building was not in use more
than three times a week, the system was
not in constant service. Each time it
was put in operation the water would
leave the gage glass entirely and would
return only when the pressure was low-
ered to the zero point or near it. At fre-
quent intervals water hammer would de-
velop in the coils.

Fic. 1. Original Connections to Boiler

Inspired by a desire to know the cause
of the trouble, the writer secured per-
mission to look the system over and
make the necessary repairs. A brother
engineer was called in and a change
was made as shown in Fig. 2. A hole was
cut in the boiler shell near the top head
and a 3-inch "pad" was bolted on and
connection was made with the main as
shown. The system now works perfectly
and the water level remains practically
constant.

First Floor Line

Fic. 2. New Arrangement of Piping

The water hammer was undoubtedly
caused by the loop shown in Fig. I, as the
water resulting from condensation in the
main would run to the lowest point, and
when the pocket was full the water would
be blown out into the coils and radiators.

Taking out the pocket, as shown in
Fig. 2, stopped the water hammer, and in-
creasing the size of pipe from the boiler
to the main eouali/ed the pressure and
allowed the condensation to return with
a head low enough so thai the coils were
kept free of water.

LETTERS

A'entilation of Buckingham
Palace

To keep the air in a room fairly sweet,
say not to contain more than from seven
to eight parts of carbon dioxide in 10,000
parts of air, there should be a supply of
,S00() cubic feet for each person per hour,
according to the British School Board re-
quirements. A room 30 feet square by
15 feet high contains 13,500 cubic feet
of air, and to change this 10 times per
hour will mean an hourly supply of 135,-
000 cubic feet. A cubic foot of air in-
creases approximately one grain in weight
for every degree fall in temperature. If.
therefore, the outside temperature is at
30 degrees and the inside at 60, a cubic
foot outside weighs 30 grains more than
the same volume inside, and to attempt
to ventilate a room by an open window
under these circumstances would cause

ing boxes and chambers to be cleaned
as quickly as possible, as the cotton-wool
screens are in use only six hours before
they are as black as the proverbial "ace
of spades."

A duplicate plant has recently been
added, the only difference being a glazed-
brick filter chamber to take the place of
the sheet-iron one first planned.

H. G. Boyle.

Cheshire. Enc

\'apc)r Pump Troubles

The article by John Watson on page
438 of the issue of September 19,
"Potblyn — Pump Doctor," calls to mind
a number of experiences I have had
with pumps and receivers in connection
with low-pressure heating systems. I
have been led to believe that the trouble
is due to a variation in pressure in the
receiver rather than to a variation of
the temperature of the water, and I have
reasoned it out in this way:

-1

' Connecting /

i

C7— J

Elevation .

General Layout of Ventilating System

a serious draff, as the air obeys the
natural law of gravitation.

The illustration represents a ventilat-
ing system which was installed in Buck-
ingham palace for the late King Edward
VII. Fresh air is drawn in by a motor-
driven fan having a 22-inch inlet and a
36-inch runner, rotating at from 230 to
350 revolutions per minute. The air pre-
vious to reaching the fan is brought in
contact with a spray of water, which
washes the particles of soot from it. It
then passes through brass screens of 144
meshes to the square inch and is de-
livered by the fan. The latter forces it
through two tubular heaters, cither of
which may be cut out as the requirements
necessitate. A bypass is also available
to pass air direct from the fan to the
filter chamber if the rooms arc too warm.

The air when in the filter chamber is
forced through 3 inches of cotton wool,
and may be perfumed if required, or pure
oxygen may be added from the tanks
provided for that purpose. The plant
has been designed to enable the connect-

Take a low-pressure heating system
working at five pounds pressure. The
receiver will be filled with steam above
the water level at a pressure anywhere
from five pounds down. Then if cold
water is admitted into the steam space,
the pressure will immediately drop, diie
to sudden condensation of the steam,
down to a point where the water begins
to boil, and this reduction of pressure
seems to be sufficient to overcome the
head of water, and any displacement
of the plungers will be filled with vapor
instead of water. It is a noticeaWe fact
that when trouble of this kind occurs
the water is usually very hot.

I have also had the same tiling happen
where no makeup water was used, the
cause being the irregular return of the
condensation due la an iti7properlv
drained heating system.

On attaching a low-pressure gage to
the receiver. I noticed that whenever one
of these slugs of water came, the needle
would drop back on the pin, and away
would go the pump. I have been able

650

POWER

October 24, 1911

to entirely overcome this trouble by put-
ting in an equalizing pipe between the
low-pressure header and the receiver.

In one case — that of a new installation
— this equalizer was made also to answer
the purpose of a drain for the low-pres-
sure header. In this case the make-
up water was introduced into the suction
pipe between the pump and the receiver.
The pump would operate continuously
without any noticeable variation in speed
whatever, but on closing a valve placed
in the equalizing pipe, the pump would
immediately show a tendency toward ir-
regular running. The pressure on the
header was kept constant by a reducing
valve. Upon shutting down the sys-
tem, the throttle to the pump had to be
closed as soon as the steam supply was
cut off. Otherwise the pump would race
as soon as the pressure went down,
though it could also be quieted by the
introduction of cold water to the suction
pipe through the makeup pipe.

E. W. Clinehens.

Troy, O.

Cold Water in Returns Causes
Pump to Pound

Potblyn, the pump doctor, brought up
a subject which interests me and also
gave me considerable trouble. One
plant of which I had charge had a cold-
water connection to a small receiver con-
nected to the pump suction. The re-
ceiver was also connected to the feed-
water heater, and to the return main
from the heating system.

We took a large amount of the boiler-
supply water from the heating main.
This water and the water from the heater
was nearly 212 degrees in temperature
but the firemen would rather let cold
water into the receiver than use the
heater properly. If they let the re-
ceiver get full of cold water while the
pump was idle, it would work without
pounding but if they turned the cold
water in while the pump was working it
would make a terrible noise.

It always seemed queer that the fire-
men would persist in disregarding orders,
even after I explained the injurious ef-
fects of using cold water in a boiler
and how it wasted coal and made more
work both in firing and in cleaning.

I never overcame the trouble fully for
it was necessary to have the cold-water
connection for another purpose. 1 be-
lieve that a 54-inch hose-spray nozzle
screwed onto the pipe inside of the re-
ceiver would have remedied matters, for
in that way the water would have been
sprayed through the steam and over the
hot water and would have then been at
the same temperature as the other water
in the receiver.

Roy V. Howard.

Tacoma, Wash.

Fatal Steam Pipe E.xplosion

in England

By John S. Leese

The bursting of the main steam pipe
in the Leigh Spinning Company's mills
at Atherton, Lancashire, England, re-
cently, claimed si.x victims.

The cast-iron pipe, 10 feet long, with
a boiler pressure of 145 pounds per
square inch, was a part of the line be-
tv.-een the boiler and the engine. Its
internal diameter was l^i inches, exter-
nal diameter 9 inches and it was S/x inch
thick. The pipe was covered with non-
conducting material and had been in-
stalled in 1902.

The accident occurred at 1 :45 p.m., six
mill hands being fatally injured and
many more severely hurt by the escap-
ing steam. Knocking or water hammer
had not been detected in the pipe line;
it had never been uncovered or examined
since its installation. The pipe burst in
the middle of its 10-foot length. An
examination of the point of rupture
showed that the metal was nearly lil
inch thick at one side while the other
was reduced to i\i inch. This was evi-
dently due to the core having shifted
from its central position during the cast-
ing process and to its presence the acci-
dent is directly traced.

New Zealand's Water Power
Development

It is reported by Vice-consul General
Henry D. Baker, who is on special ser-
vice in New Zealand, that the develop-
ment of the water resources of that coun-
try will soon be begun.

Parliament has empowered the minister
of finance to raise S2, 433,250 for the
establishment of electric-power works
and the utilization of New Zealand's
water power.

Evan Parry, a well known English en-
.gineer, whose experience has been con-
siderable in the United States, Canada,
the United Kingdom and Spain, has been
named as the first electrical engineer
for public works. He will make a spe-
cial study of the latest developments in
water-power works in this country be-
fore proceeding to take up his duties in
New Zealand.

Work Bet^un on Panama
Expo.sition

President Taft, on October 14, started
the work on the Panama Pacific Interna-
tional Exposition by lifting the first
spadeful of soil at Golden Gate park. A
crowd of 150,000 people witnessed the
ceremony, and as the President raised
the official exposition fiag, a thousand
pigeons were released, making a very
impressive picture.

Ground was broken in the Stadium,
one of the central points of the exposi-
tion.

Charles C. Moore, president of the ex-
position, officiated at the opening exer-
cises and promised that it would be the
greatest exposition that the world has
ever witnessed. The mayor of San Fran-
cisco, P. H. McCarthy, also spoke along
the same lines, after which Governor
Hiram Vf. Johnson introduced President
Taft.

At the close of the ceremonies, Mme.
Lilh'an Nordica, the well knowm opera
and concert singer, led the vast as-
semblage in singing the "Star Spangled
Banner."

. Economical Pumping

The Cincinnati waterworks have puri-
fied and pumped into the distribution
services during the nine months of the
year 1911, 13,028,752,750 gallons of
water at a total cost of $180,055.97; this
is .S13.82 per million gallons. The pro-
gressive increase in the economy of op-
eration is shown by the following fig-
ures: 1908, cost per million gallons,
$16.09; 1909, S15.74; 1910. $14.36; 1911,
based on the first nine months, S13.82.

SOCIETY NOTES

The annual meeting of the American
Society of Mechanical Engineers will be
held at the Engineering Societies build-
ing. New York City, on December 5 to 8.

The Engineers' Blue Club, of Jersey
City, N. J., will hold its tenth anniversary
banquet on October 28 at the Columbian
club in that city. Governor Woodrow
Wilson, of New Jersey, Mayor H. O.
Wittpenn, of Jersey City, and Judge
Robert Carey have promised to be pres-
ent. Tickets may be obtained from John
J. Calahan, Technical Industrial School,
Jersey City, or M. J. Hickey, chief engi-
neer, Scott & Bowne building, 409 Pearl
street. New York.

PERSONAL

Gano Dunn has just returned from
abroad, where, as a representative of the
United States Government, and as presi-
dent of the American Institute of Elec-
trical Engineers, he has been attending
the International Electrical Congress at
Turin and the m;eting of the Interna-
tional Electro-Technical Commission, the
body that has been organized to bring
about international uniformity of stand-
ards and practice in the electrical in-
dustry. Mr. Dunn, who for many years
was first vice-president and chief engi-
neer of the Crocker-Wheeler Company,
and is a past-piesident of the New York
Electrical Society, has been elected a
director and a vice-president of J. C.
White & Co., Inc.

Vol

NEW YORK, OCrOHKR SI, 1911

No. IS

THIS man is a steam filler. His standard
wages in Xew York are S5.50 per day.
He works eight hours and is careful
not to do too much in that time and thus
keep some other steam fitter out of a job.

The man who is superintending the steam
fitter's work is an engineer.

He has charge of the engines and boilers,
the electric generators and motors, the pumps
and healers and piping and radiators and
elevators of a large building.

A trained mechanic, he knows more about
steam fitting than the man who is working
for him, ancl is, besides, an electrician, under-
stands the intricate processes of combustion,
knows how to set valves, measure horse-
power, test boilers and keep machinery up
to its work, delect incipient failure and
foresee and obviate shutdowns and accidents.

He directs the activities of many men.
The difference between competency and in-
competency on his part may amount to thous-
ands of dollars a year in the cost of running
the plant.

Negligence or failure may result in ex-
pensive and annoying interruptions or even
in serious disaster. lie
works 1 2 or more hours
a day regularly, Sun-
davs and holidays us-
ually, and many even-
ings.

And for this he
draws three or four
dollars a day!

Why?

How much do vnii,
Mr. Employer, pay
your engineer?

P^t youi" ^v^cnch Jov/nl*
and MUppurt thatuknder|

How do his allainmenls and responsibili-
ties and hours and wages compare with those
of the responsible heads of other depart-
ments of your business?

Why do you pay him less than you do the
pipe filler who works under him?

Because you cannot get a pipe fitter for less 1

And vou cannot get a pipe fitter for less
because the pipe fitters have gotten together
and agreed not to work for less.

On the other hand, the engineers, recog-
nizing themselves as in the executive class,
have been trying for the past 30 years
to improve their condilion by increasing
I heir efficiency and their knowledge of their
business.

Their best supported organizations dis-
countenance strikes, and tolerate no inter-
ference between employer and employee.

Thev seek to educate and improve their
members in the faith that greater ability and
better service will win the recognition which
they deserve.

Do you. Mr. Broadminded Kmployer. wlio
see further than the
edge of the payroll,
want to see this policy
win. this faith fulfilled,
or do you want to
drive the engineer
from his present motto,

To EARN MOKE,
LEARN MOKE,

to the more trenchant
slogan,

To GET WHAT VOtl

EARN, ORGANIZE!

652

POWER

October 31, 1911

New Pumping Station for London

A notable addition to London's water-
works system is the new Walton pumping
station which has recently been placed in
service. This station is located a few
hundred yards from the south bank of
the Thames at West Molesey and sup-
plies several reservoirs of the London
Metropolitan Water Board.

As shown in Fig. 1, there are three
intake tunnels from the river, running
under the towing path, and discharging
into an open concrete-lined canal (see
Fig. 2) , the latter having a length of 1450
feet and terminating at the pumping sta-
tion. Each of the intake tunnels is fit-
ted with a hand-operated sluice gate
which gives access to a screen chamber
containing stout iron screens to prevent
any drift matter from entering the intake.

The discharge side of all the pumps is
connected to two 54-inch mains running
under the entire length of the pump room,
and by an arrangement of sluice gates
they may be supplied separately or to-
gether by any or all of the pumps. These
mains lead direct to the two Walton
reservoirs and further connect with the
Island Barn reservoir, nearly two miles
distant. From the Walton reservoirs,
which are 43 feet above the Thames
river, two 48-inch mains run to the south
bank of the river; here they join a tunnel
under the river and from the north bank
continue on to the reservoirs and filter

By J. B. Van Brussel

The Walton pumping
station ptimps water from
the Thames to the Walton
storage reservoirs from
which if flows by gravity to
the filters.

A difference in level of 43
feet between the storage reser-
voirs and the filter beds is
made use of in water ttir-
bines for pumping addition-
al water into the reservoirs
and thus supplementing the
work of the main pumping
engines.

The total capacity is 130
million gallons per 24
hours.

beds at Hampton. The latter are at about
the same level as the river.

When laying out the system it was
decided to make use of this difference in
level between the Walton reservoirs and
those at Hampton; consequently, the

pumping machinery at the Walton station
is in two groups. The river water is first
pumped into the reservoirs by four dupli-
cate units, each consisting of a 14, 23 and
38 by 30-inch vertical triple-expansion
condensing engine running at 150 revolu-
tions per minute and coupled direct to a
two-stage centrifugal pump capable of de-
livering 25 million gallons of water per
24 hours against a total head of 64 feet.

The other pumping units are of an
entirely different character and consist
of three centrifugal pumps, each driven
by a twin horizontal mixed-flow water
turbine utilizing the energy of flow from
the Walton reservoirs to the Hampton
filters. These are each capable of de-
livering 10 million gallons of water per
24 hours against a head of 64 feet and
are placed in parallel with the main
pumping engines. By this arrangement
it \3 possible to recover approximately
one-third of the power originally em-
ployed in pumping into the reservoirs;
that is, the main pumping engines are
required to operate only two-thirds of
the time which would otherwise have
been necessary. It is estimated that a
saving of 10 to 12 tons of coal per day
under average pumping conditions is thus
effected. Both the engine- and turbine-
driven units are shown in Fig. 3.

Steam for the main pumping engines
is furnished at 200 pounds and from 120

Fig. 1. Intake Tl'nnel and Gates

October 31, 1911

POWER

653

Fig. 2. Intake Canal from River to Pumping Station

Fig. 3. Engine Room, Showing Both STPAM-t.Hivi n and Water-drivfn Units

tj54

POWER

October 31. 1911

to 150 degrees superheat by ten Babcock
& Wilcox boilers arranged in five bat-
teries of two each, as may be seen from
the general plan, Fig. 5. These boilers each
have 1800 square feet of effective heating
surface and 37.4 square feet of grate
surface. They are provided with chain-
grate stokers fed from an overhead bunk-

an electrically operated traveling crane
(see Frg. I) carrying a grab bucket.
After transporting the coal a short dis-

y

Fig. 2, which carries the coal in skips to
the overhead bunker in the boiler house.
From here it is fed to the stokers by
chutes containing automatic weighing
hoppers.

Direct current at 210 volts for lighting

Chimney

a r:j^

i_Ja'lfeOf

Fic. 5. General Plan of Pumping Station

er. By reference to Fig. 6, it will be tance from the river, the crane deposits and operating the coaling crane, conveyer
noted that the roof of the boiler house it into a hopper erected over one end of and large valves is furnished by two
is designed so as to admit sufficient a continuous aerial conveyer, shown in steam-engine-driven generating sets,
light over the boilers in spite of the pres-
ence of overhead bunkers.

Fic. 4. Pipe Pit

The method of handling the fuel at this
plant is novel. Coal is brought up the
river in barges from which it js taken by

Fig. 6. Boilkr Roo.m

October M. 1911

POWER

Vibrations of the Indicator Pencil

The diagrams shown in Fig. 1 were
recently published for criticism in
Povx ER with especial reference to the ex-
pansion line. They are evidently taken
from a high-speed engine with an ex-
ceedingly rapid cutoff. They are excel-
lent diagrams and the engine from which
they are taken is without doubt econom-
ical in the use of steam. However, as no
accompanying data were given, the dis-
cussion here will be confined only to the
"lagged expansion line" and in but a
general way.

Too much should not be expected of
the indicator; it is a clever piece of
mechanism and a very useful instrument,
but its every whim and fancy must be
well understood to correctly interpret its
records. .An indicator diagram at best
cannot be relied upon closer than 3 per
cent. Engineers are too prone to be

Fic. 1.

fussy over an ideally formed diagram
even to the sacrifice of smooth operation
and economy of the coal pile. The dia-
gram, it must be remembered, is a means
and not an end.

Irregularities in the diagrams can be
caused bv leakage of steam into or from
the cylinder, but such distortions in no-
wise approach a series of waves. When
such leakage occurs on the expansion
line the general trend of the line is
decidedly altered and it will be noticed
in the figure that this is not the case,
for the expansion here is normal and
continuous.

TTie jagged evpansion line is due to

By J. W. Tavlor

.\)i iiiKily.sis oj the causes
oj the jas^gcd expansion line
oj 0)1 indieatoy iliagnuu
oik! the efjeet upon indi-
eoted results.

to vibration, which has an\ where near
this frequency.

The diagram in Fig. 2 is taken from
Fig. 1 with the crank circles added. It
will be noticed that the projection of
the waves upon the circle subtend equal
arcs showing a regularity of period
characteristic of a vibrating body. The
arcs subtended in this case are about 12
degrees. Assuming an engine speed of
150 revolutions per minute, or 2.5 per
second, would give

2.,s X .^6o .

= 7S oscilltiltoiif per second

Fig. 3 shows the formation of such an
expansion line by the combination of

Occasionally diagrams will show sev-
eral waves following admission, and if
these are projected to the crank circle,
as in Fig. 2, they will show the same
period of vibration as occurs following
cutoff. Generally, however, there is but
a partial vibration and that but indis-
tinctly shown if at all. That a pencil
overruns its mark is due to the inertia of
the reciprocating parts, and it leaves but
a rudimentary vibration or "horn," as it
is usually called. Still it is possible for
several vibrations to be penciled at this
position without showing otherwise than
as a single line, for the crank can swing
here through a decided angle without
moving the drum perceptibly.

The vibrations of the arm are set in
iTiotion by a sharp blow produced by a
rapid change of pressure; pressure from
a quick early cutoff drops very rapidly.

normal expansion and vibration curves,
considerablv enlarged for clearness. The
sinuous vibration curve A shows a grad-
allv decreasing wave amplitude such as
occurs when the cause of disturbance is
removed, the expansion curve R being
taken from the same point of cutoff as
in Fir. 1. The forward movement of

Fig. 3.

The pressure at compression rises very
rapidly also, hut the continually lowering
expansion line is more favorable to the
existence of vibrations than is the con-
stant admission line. It appears from
the usual diagram that the pressure
changes from the end of coiupression to
admission are even greater than those
at cutofl. They are not necessarily so,
however, lor the reason previously cited.
If a diagram is taken with the drum
cord driven bv an eccentric it will he

50 "p

ISO F. p.m. Locomolh

Fig. 4.

the vibrations of the indicator arm, the
frequency of the sinuous waves being
from 20 to V) times the impressed fre-
quency of the engine vibrations. The arm
is the rmly pan of the indicator, subject

both curve? is in step with the engine
piston The mode of combination is
quite evident from the illustration and
the familiar appearance of the resultant
curve C is conclusive.

seen that this rise of pressure is surpris-
ingly gradual in the majority of cases.
Such a diagram, called an "eccentric dia-
gram." is an excellent means of analys-
ing the cb.ingcs taking place af points

656

POWER

October 31, 1911

which are but poorly brought out on the
usual diagram.

In FiR. 4 is brought out clearly the
type of engine upon whose diagrams the
vibrations of the indicator arm are apt
to appear, and these are all at about
the same point of cutoff. The excessive
wire-drawing in the locomotive diagram
has the san\e effect upon the indicator
arm as does the cutoff in the four-valve
engine. The speed of cutoff at early
points in many four-valve engines is
even more rapid than in the Corliss en-
gine. While the pencil drops through

he performed by turning the indicator
arm. The diagrams in Figs. 5 and 6 are
taken from a 20.\20-inch four-valve en-
gine running at 170 revolutions per min-
ute. Each hgure. shows a friction and a
load diagram. All were taken within a
few minutes of each other, with the con-
ditions, as far as the engine was con-
cerned, as nearly alike as possible in
the two figures. Those in Fig. 5 were
taken with the regular indicator arm, and
the waves show a vibration frequency of
about 108 oscillations per second. In Fig'.
6 the arm was turned down to about

the distance S the piston travels the dis-
tance D, a projection of which gives the
corresponding angle passed through by
the crank. From this angle and the
speed of the engine the time occupied by
the pencil in dropping the distance S is
readily obtained. This time is equal to
the angle passed through by the crank
divided by the product of 360 and the
revolutions per second. In diagram No.
1 this time is 0.0085 second; in No. 2,
0.0200 second; in No. 3, 0.0225 second;
and in No. 4, 0.0093 second. From this
it is evident that the time occupied in
dropping the distance S is over twice as
great in Nos. 2 and 3 as in Nos. 1 and
4. .\s the energy of a moving mass is
proportional to the square of its velocity,
the disturbing effect set up in the arm,
while whipping through this distance, is
over Syi times as great in the first and
fourth diagrams as in the second and
third.

The frequency of vibration depends
upon the length and section of the arm
and the weight of the pencil holder. The
amplitude also depends upon these fac-
tors and in addition upon the severity
of the shock. This accounts for the
change in appearance of these vibrations
with the change in cutoff. Though the
intensity, location and number vary from
zero to maximum cutoff, the frequency is
constant. At the later points of cutoff
the pressure falls off much more gradu-
ally during expansion than at the early
points and in all single- and four-valve
engines the later cutoff is much slower
in action than the early cutoff, which
lessens considerably the whipping effect
of the indicator arm.

The initial amplitude of the wave in
Fig. 1 is about 9/32 inch, which gives a
deflection of 9/64 inch each side of the
normal. A very slight pressure on the
end of the arm will easily give this de-
flection and a sharp whip of the arm will
readily duplicate it.

With an engine giving this wavy dia-
gram, a very interesting experiment can

one-half the pitch by the addition of a
piece of lead near the pencil. The waves
in this case represent about 56 oscil-
lations and the additional weight not only
reduced the number of vibrations per
second but very naturally increased the
amplitude and wave length. The friction
diagram here is a striking example of
arm vibrations. The steam distribution
in these two cases is precisely the same
regardless of the appearance of the dia-
grams, for certainly the addition of a
little lead to the indicator has no influ-
ence upon the steam consumption of the
engines, nor would an indicator with a
stiffer arm giving a more nearly ideal
diagram alter the case at all.

It will be noticed in Fig. 3 that the
waves subtract from the normal expan-
sion line somewhat more, in subtended
area, than they add. However, as this

Bell Crank Repair

The bell crank on the head-end ex-
haust valve of the low-pressure cylin-
der of a 500-horsepower cross-compound
Corliss engine broke one morning while
the engine was running under apparent-
ly normal conditions. The fracture oc-
curred as shown in the illustration and
the cause is not known.

As it w^as necessary to use the engine
day and night a temporary repair was

Repaired Bell Crank

made which proved so successful that
the repaired bell crank will doubtless
be left in place as long as it will safely
operate. A piece of Sg-inch steel plate
was shaped to fit the inside of the hori-
zontal arm of the bell crank, and four
holes were drilled in one end and one
hole in the other. A stud was placed
through the single hole for the valve-arm
connection which secured that portion of

Fig. 6.

scalloped edge is but a small fraction
of the entire diagram area, the error
thus introduced is small; and having a
negative sign it is on the safe side and
can well be neglected. Even with a fric-
tion diagram as excessive as that of Fig.
5, the error introduced will be well with-
in the inherent error of the indicator.
This means that the actual mean effec-
tive pressure of the cylinder can be ob-
tained by following the jagged expan-
sion line.

These sinuous lines are very frequent-
ly observed. They appear on the dia-
grams of a number of both .American
and European engines. With such dia-
grams the actual steam changes can be
closely followed by drawing a median
line through the waves.

the fractured bell crank to the reinforc-
ing plate when the stud nut was turned
up tight. Four holes were then drilled
in the stub end of the crank and tapped
to correspond to the four holes in the
reinforcing plate; four tap bolts were
used to secure the plate to the arm.

A valve should be placed as close to a
pump as possible, in order to allow cut-
ting the pump out of service without
disturbing the pipe or interfering with
other methods of feeding. There should
be three valves in the pipe leading from
the pump to the boiler, one between the
boiler and the check valve; one con-
venient to the boiler front to be used in
the feed regulation; and one close to
the pump. — Ex.

October 31. 1911

POWER

657

Limitations of the Rope Drive

The adaptability of rope for alinost
evei>' condition of power transmission
has been so ardently urged by some and
so vehemently condemned by others that
one may well ask whether there is really
any place in which it is justifiable to
use the rope drive. In an effort to clear
away some of the confusion and to set
forth, if possible, the limitations to the
efficient use of rope transmission, inquirj-
was recently made in a variety of in-
dustries and among a considerable num-
ber of designing engineers. Each was
asked for an opinion as to whether the
use of rope was growing in relation to
belts, and when and why rope was to
be considered preferable to belts.

The replies to these inquiries may be
roughly grouped into the following
classes: Twenty-three from textile man-
ufacturers, twenty from paper manu-
facturers, five from workers of metal,
principally machinery manufacturers;
twelve from designing and consulting
engineers, and three from diversified in-
dustries. The total number of replies
represents only 63 per cent, of the in-
quiries sent out. The fact that the re-
plies received from the various classes
is not proportional to the inquiries sent
to each suggests that where the per-
centage of replies is low there has been
comparatively little experience in the use
of rope transmission. The letters pre-
sent such a wide diversity of opinions
that a casual reading leaves one as much
confused as at the beginning. But a
careful analysis and classification of all
of the letters disclose some interesting
and instructive groupings of opinions,
and reveal more or less logical reasons
for the differences in opinions.

First of all, it appears that all except
the most violent opponents concede to
rope a field of somewhat elastic propor-
tions in which it is recognized to be
better than belts, gears or chains. In the
second place, it is noticeable that there
is a relatively sharp distinction between
the attitude of the consulting or design-
ing engineer and that of the individual
who is in daily touch with the operation
of a rope drive. Doubtless because the
former views the subject in a broader
and more critical way, he sees imperfec-
tions which do not appeal to his less
technical brother. In fact, the man on
the job seems to encounter but a small
proportion of the troubles set forth by
the man who makes the plans. From this
it might be assumed that the imperfec-
tions of the rope drive are largely theo-
retical and that they have to do with
efficiency rather than with mere ability
to transmit power.

Because the rope has been so gen-
erally regarded as always the rival of the
belt as a medium for transmitting power

By Walter B. Snow

Inquiries among manu-
facturers, mill owners and
consulting engineers brought
forth diversified opinions
regarding the relative mer-
its of rope-drive, belt-drive
and electrical transmission.

The conclusion to be
drawn from the majority of
the replies indicates that
rope transmission has a good
field where large poicers are
to be transmitted atid the
distances lie betweoi j^ and
150 feet.

between rotating members, the real fact
that each has its distinct field has been
somewhat overlooked. True it is that
these fields overlap in many instances,
but this only emphasizes the point that
there are extremes in which only one of
the two means of transmission ever
rightly belongs.

It was freely predicted not long since
that the advent of the individual motor
drive would mark the passing of both
belts and ropes from the power-trans-
mission field. Indeed, many shops and
mills were changed over to accommodate
the all-conquering motor. But wider ex-
perience with the electric drive has de-
monstrated that it, too, is circumscribed
in scope and cannot be specified offhand
as the best. Its application is undoubtedly
widespread and some remarkable econ-
omies have been effected by its use in
places for which it is peculiarly fitted.
The situation with regard to the direct
drive was clearly presented by F. W.
Taylor in his address as president of the
American Society of Mechanical Engi-
neers, in which he said:

"Of late years there has been what
may almost be termed a blind rush on
the part of those who have wished to in-
crease the efficiency of their shops, to-
ward driving each individual machine
with an independent motor. I am firmly
convinced, through large personal ob-
ser\'alion in many shops and through
having systematized two electrical shops,
that in perhaps three cases out of four
a properly designed belt drive is prefer-
able for machine tools."

Here the motor competes only with the
belt, for the power to be transmitted is
small. With increase in load and dis-
tance the field for the rope broadens,
the opportunity for efficient use of belts

is practically removed and electricity re-
mains as the only rival. B\it except
where the mill is electrically operated
throughout, the main drives still fall to
the lot of the rope.

As between the two systems of rope
drive, American and English, opinion
seems to lean toward the use of the Eng-
lish system of a multiplicity of individual
loops for heavy transmission, as against
the American method of employing one
long rope looped again and again over
the sheaves and then carried over a ten-
sion sheave for lighter and especially
complicated drives. The essential ad-
vantage of the former and older method
is that the breaking of a rope will not
cripple the drive, the remaining ropes
dividing the work of the broken member
among them. In the American system it
is claimed that equal tension is obtained
in each loop and therefore perfect dis-
tribution of the power is transmitted
along the loops. All the loops being
equally loaded, the possibilities of a
break are greatly reduced, and it is
maintained that much longer life is as-
sured for the rope as well as greater
transmitting efficiency due to the steady
tension.

The variety of existing opinions re-
garding the use of rope for transmis-
sion which was revealed by this investi-
gation cannot be better displayed than
by quotations from some of the letters
received. The superintendent of a large
paper mill writes:

"We use but one rope drive in this
mill for the transmission of about 300
horsepower. We would like, however,
to have many more rope drives if we
could induce their further adoption. We
believe that th» use of rope transmission
is increasing and our experience is that
the rope transmission is receiving more
attention today than it has ever done.
Part of this may be due to the greatly
increased cost of rubber and leather
belting and to the usually unsatisfactory
results obtained by the use of cotton
belting on account of its inferior tractive
power. The first cost in connection with
the adoption of the rope is lower as com-
pared with belts and tlie subsequent up-
keep is smaller and the results obtained
where the rope drive is adequate for
the services put upon it are much better
than those obtained with belts.

"While much of the foregoing consists
of merely bald assertions, they are the
results of hard practical experience. At
the present time we arc installing con-
siderable new machinery in one part of
our mill and have arranged to use t^pe
drives instead of belts in a place and
for a service where rope has rrcver been
used before. We think so well of rope
drives that we arc contemplating using

658

POWER

October 31, 1911

them wherever possible in new installa-
tion in the future."

In distinct contradiction to the pre-
ceding, although qualified by limitations,
is this statement of a well known firm
of consulting engineers:

"We do not consider rope preferable
to belts. At best, rope transmission is
only to be used in exceptional cases. For
indoor work, such as the driving of ma-
chine tools, transmission of power from
line shaft to countershaft, and even from
the engine to the jack shaft, rope trans-
mission at no time has been and is not
now a serious rival of belts. The only
cases in which rope can be advantage-
ously used is where power is to be
transmitted, say more than 75 feet and
less than 150 feet. For greater distances
it is probable that electric transmission
would be the cheapest and best. For
shorter distances than 50 feet the use
of belts would be preferable."

Another paper manufacturer presents
a case for the exclusive use of rope in
these words:

"We use rope drives for several pur-
poses. The largest of these is used for
driving a 600-kilowatt generator, and has
proved very satisfactory in every case.
This is an instance where it would be
practically impossible to use belts as the
generator is connected direct to two
waterwheels. We have several other rope
drives for the transmission of power to
a point too far from the source of power
to be able to use any other method than
electrical transmission.

"The tendency seems to be to use rope
in preference to belt wherever the horse-
power to be transmitted is large and
where there is ample room for sheaves
on the driven machinery."

In contrast is this statement from a
textile manufacturer:

"We are not using rope drive. We
did use this system in our old mill, but
had so much trouble with irregularity
of the English system of rope driving
after the ropes began to wear out and
new ones had to be put on, that we aban-
doned the rope system, and have sub-
stituted belt drive instead. From our ex-
perience we consider belt drive prefer-
able, although it costs a little more in
the first place. Rope driving, according
to our experience, runs fine for a few
years, or until the ropes begin to give
out, when everlasting trouble commences
unless the mill substitutes a whole new-
system for every individual drive. New
ropes will not work well together with
old ropes which have worn down to a
smaller diameter."

A firm of consulting engineers sum-
marizes its opinion thus:

"In our opinion the use of ropes is not
growing. It is also our opinion that the
use of belts for transmitting power is
decreasing. While motors are not uni-
versally adaptable for power transmis-
sion, there are many points in their favor

in such plants as we have to do with and
we believe their use is increasing, with
a consequent decrease in the use of belts
and ropes. We have found it expedient
to use ropes instead of belts for trans-
mitting power from waterwheels and in
some other cases where dampness would
prevent the satisfactory use of leather
belts."

Some of the reasons for these wide
differences in opinion are to be found in
the following somewhat explanatory le;t-
ter from an engineer noted for his con-
servatism :

"So far as my observation goes, I
should say that with the introduction and
extension of the use of electric transmis-
sion, the use of rope transmission would
diminish at a more rapid rate than would
the use of belts. The reason for this is
that ropes have been used very largely
for main drives from engines, and in
nearly all cases the counterdrives have
been belts. With the use of electric
transmission, the main drives are done
away with, but the drives from the motors
and the counterdrives remain as formerly.

1.9

head shafts in a mill. Also, the use •/
ropes will avoid the extremely wide belt
wheels. Furthermore, in places where
power must be transmitted mechanically
from one building to another and around
corners, ropes are preferable to belts.
Electrical transmission enables the elimi-
nation of these awkward drives."

Manifestly, the limitations of the rope
drive are set by those of the belt, for
electric transmission may supplant either.
Within the field of efficient operation of
the belt the rope is a poor rival, but be-
yond the limits of practicable belt lengths
or widths the rope finds no superior;
here it reigns supreme. Such is the evi-
dent consensus of opinion.

Temperature Expansion

Diagram

By W. Vincent Treeby

The accompanying diagram shows the
amount of linear expansion for copper,
mild steel and cast iron. It should be
useful to designers in laying out steam

1

\

/

— -

/

/

/ ,

,

/

/

I

—

/

y

/

y .

/

/

/

y^

/

/

/

V

fi

V

/

i

1

\ M

f\

p

<^'

/

y^

&'

/

/

V

/

/x

y

/

/

^

y

!

/

/

f

,

/

O.

^

i

/y.

^

1

/

i

0 10 20 30 40 50 60 70 80 90 lOO HO leo 130 140 150 160
Temperature Rise in Degrees Fahrenhei+ '"""^

Diagram Showing Amount of Expansion in Copper, Steel and Cast
Iron for Various Temperature Chances

"I believe that rope transmission is
preferable to belts sometimes where
large amounts of power must be trans-
mitted, such as from large engines or to

piping and similar work where the ma-
terial is affected by changes of tempera-
ture and provision must be made for
expansion to take place.

October 31. 1911

POWER

659

Efficiency of Reciprocating Engines

In the development of the reciprocat-
ing steam engine there are to be noted
the gradual improvements such as in-
creasing steam pressure and the use of
inore perfect expansion gear; also, the
more rapid advancement resulting from
compounding and condensing and par-
ticularly superheating.

Table I shows the effect of vacuum on
the steam and heat consumptions in a

TABI.K 1. I.NFLUE.NCE OF V.ACUUXt ON
.STE.\.M AND HE.\T CONSUMPTIONS

,

~ i.

u

o

It

«ie|

£"l

r?^

c 'z

uu

si|

.= a.

%k

uii

=1""

ii-a

c

c ^

2 ;TI

t^-

u

>

^i

?S^I.

fc»<

l

K'-~

l.iS

4 06

20.2

S (M)

86.-,0

140

3 00

24.0

7.71

S4<)(l

122

1.84

26.2

7..il

S4(>!>

109

1 to

27 S

7.3S

S3S'.I

SO

0 03

2.S . 7

7 31

S42(l

an

0 37

2S,<)

' "'

S44;i

locomobile reciprocating engine with an
initial pressure of 220 pounds, a terminal
pressure of 8.8 pounds and an initial
temperature of 662 degrees Fahrenheit.

glSPOO

- ^''^ i /SS°r/>hr 'rterrnrJ'iTteSijptrherrt

%3 73 t» 103 ll.» 133"

Terminol tVffiio'*.

Pownd5 per SqiKJre Inch Ab5. **>-•*

Fic. I. Results op Tests with Hioh

Degrees of Primary ano Secondary

Superheating

The value of superheating is based on
the l(.3ser heat-conducting capacity and
the lesser flow friction of superheated
steam; and the consequent smaller loss
through heat interchange between the
Steam and its confining walls finds ex-
pression in the increase of cylinder efB-

By K. Heilniann

Performance of locomobile
engines, the influence of
primary and secondary
superheating and of vacit-
II III 11 pan the steam coii-
sumphou; also a study of
the heat losses in the cylin-
der.

•K.vlrailPd

an.l inuishii.-.l l.v \V. F. .\l..iia

Kban I'lom a

papiT read Ijolole vai-ioiis local

branches of

the \ ereins Deiitscher Inge-

nieme b.v K.

Heilman. who is chief enslneei

of thp K. \V

ilf estalillshnicnt at MaL'debnrg.

ciency.* The line of this latter efficiency,
for initial superheating, rises quickly to
7,S0 degrees Fahrenheit and from 120
degrees of intermediate superheating it
rises rapidly to about H60, to follow
thereafter a flatter curve. With these
temperatures the steam leaves the low-
pressure cylinder in a dry, saturated con-
dition. Up to the highest temperatures
the curves of steam and heat consump-
tion show a falling tendency and that of
thermodynamic efficiency a rising one.

The convergence of the Rankine cycle
curves, with and without secondary super-

heating is not insignificant; while, on
;hc contrary, with high initial superheat-
ing it constantly diminishes. The saving
of steam through an intermediate super-
heating of 120 degrees with 390 degrees
of initial superheat amounts to about 10
per cent.; with 570 degrees about 8
per cent.; with 750 degrees about 5.5 per
cent., and with 930 degrees about 3.5
per cent., and because of the heat re-
quired for the intermediate superheater
the average economy in steam consump-
tion, as before, is about 3.5 per cent.
less. In the case of the self-contained
type of engine, such as the Wolf "loco-
mobile," the secondary superheating by
waste flue gases is of negligible expense.

The curves shown in Fig. 1 are the
results of three series of tests notable
mainly for the high degrees of primary
and secondary superheating. The lower
set of curves show the dependence of
the indicated load on the terminal pres-
sure. The load curve lies higher as the
superheat is greater, and the resulting
difference, due to the amount of super-
heat, on the indicated load with a given
terminal pressure is considerable.

The middle set of curves show the
steam consumption for the indicated and
effective horsepowers, the latter by the
shaded lines. The curves are flat through-
out. The higher the superheat the lower
in the curve will be the point of most
favorable steam consumption, and from

I Temperature. Oqrces^ohrcfiheit

Fig. 2. Steam Consumption ANn Thermo-
dynamic Efficiency with Different
Steam Te.mperatiires

heating, indicates that the value of such
superheating with moderate initial super-

•The lirm 'vUlntlet efDclencv" l« n-ml here
nx Ih" e<|ii|\al<-nl of the (;4 rman flillrnrinl.
whleli .-xpr. oaci the frnrflonal value-
Str„,„ r„„',n„,ill„n In n 'niilntii- rnttlnr ,rith
_ lit. timplrtt rrprtn»fni,

Ulrnm r<.ll»7i,np»»o(i In lil^^Vlunt rmrinc

Output, Indicated Horsepower

Fig. 3. Results of Tests with Steam
AT 670 and 870 Decrees

this and from the steeper path of the
expansion line at the higher temperature,
it undoubtedly follows that high super-
heating yields a fuller expansion value.
Fig. 2 shows the subordination of
steam consumption, heal cnnsumpiinn and
thermodynamic etflcicncy to steam tern-

660

HOWEK

October 31, 1911

perature. With free exhaust, the theo-
retical influence of superheating is greater
than when operating condensing, but, on
the other hand, its effect on the losses
is less. This is noticeable in the path of
the thermodynaniic-efficiency curve.

and to the heat interchange resulting between the steam and the walls, were
from the greater temperature drops, par- taken together as residual losses,
ticularly in the low-pressure cylinder. As plotted in Figs. 4 and 5, the cylin-

ders are considered separately and are
supposed to have apportioned to them the
Figs. 4 and 5 show the dependence of actual pressure and temperature drops
When running condensing the saving the heat distribution on the load and referred to the theoretical work capacity
with steam at 660 degrees Fahrenheit is

High- Pressure Cylinder

Heat Distribution

27.5 per cent.; while when running non-
condensing the increased consumption is
37.5 per cent.

As regards the lesser steam-tempera-
ture drops with free exhaust, particularly
in the low-pressure cylinder, intermediate
superheating has but little economy sig-
nificance, and the heat consumption and
the thermodynamic efficiency are hardly
affected.

Fig. 3 shows the results from two
series of tests — one employing steam at
670 degrees and the other at 870 de-
grees. The influence of the load on the
steam consumjition is here somewhat
greater than when running condensing.

Influence of Vacuum

For vacuums from zero to something
less than 25.5 inches the steam-consump-
tion curve follows an almost straight
path; with higher vacuums it approaches
more closely the horizontal.

The efficiency of the high-pressure cyl-
inder is less than that of the low-pres-
sure cylinder, partly because the tem-
perature drop of the steam in the former
is the greater. With increasing vacuum

High Pressure Cylinder Low Pres:

39?

572

752

Low-Pre

^sure

C/I'nder

m^

Complete Engine

392

-r'

' \

^ -

/^

1 1

Util.zed

752

392

752

Temperature. Degrees Fohrenheit

Fic. 5. Heat Distribution in High- .and Low-pressure Cylinders and in
THE Complete Engine

on the temperature of the steam. Tlie
effect of throttling action on the work
capacity was determined from the MoUier
heat-entropy chart. To simplify matters
it was assumed that the actual quality

re Cylinder
Throtlling:

{Intermediate Superheate.
Inlet Fassages

Complete Enqine

Fahrenheit -

iSteam Temperatures S7S-634-Def}recs
\/ntermec/iate Superheat l^4-M5 -^ i
Initial Temperature 75Z-80T "
Intermediate Superheat 140-86 '"I
Temperature to High Pressure Cylinder 5S0-635 Degrees Fahrenheit,

194' IW Degrees oF Intermediate Superheat
Temperature to High Pressure Cylinder 750-80S Degrees Fahrenheit,—
■ 140-86 Degrees oF Intermediate Superheat 1 i

Cutoff. Per Cent.

7.J5 8.3 10.3
Terminal Pressun

Pounds per Squore Inch, Absolute

Fig. 4. Heat Distribution Depending upon Steam Temperatures

the proportionate load of the low-pres-
sure cylinder becomes greater as does
the cylinder efficiency of the complete
engine. The latter reaches its highest
value with about 80 per cent, vacuum.
With higher vacuums the losses increase,
due to the throttling effect between the
low-pressure cylinder and the condenser,

of the steam at the terminal pressure
represented the theoretical quality at a
like terminal pressure, a condition very
nearly true for the low-pressure cylinder;
also, that the loss through the incom-
plete expansion of the compressed steam
is negligible. The remaining losses, in-
cluding that due to the heat exchange

of the cylinders with complete adiabatic
expansion (Clausius-Rankine cycle). For
better comparison all values are ex-
pressed in hundredths of the theoretical
load. Finally, the losses in both cylin-
ders due to throttling action and to in-
complete expansion are taken together
and referred to the theoretical work capa-
city represented by the total pressure and
temperature drops.

The curve of utilized heat rises
rapidly and is in accord with the in-
crease of the working steam volume and
with the decrease in pressure and tem-
perature drops in the cylinder; these re-
duce the residual losses resulting from
heat interchange from about 13 per cent,
with 20 per cent, cutoff to about 5 per
cent, with 36 per cent, cutoff. It is note-
worthy that the solid-line curve of
thermodynamic efficiency lies higher than
the dotted line which refers to tests with
a higher superheat of only about 212 de-
grees Fahrenheit. In the low-pressure
cylinder incomplete expansion is the chief
source of loss.

Fig. 5 shows the heat distribution as
referred to a steam temperature corre-
sponding to a boiler pressure of 220
pounds and a terminal-expansion pres-
sure of 9.2 pounds. In the high-pres-
sure cylinder the chief losses are through
heat interchange through the cylinder
walls, and with saturated steam they
amount to about 19 per cent.; with in-
creasing superheat they fall to about 10
per cent.

The loss through throttling effect de-
creases with increasing temperature on
account of the decreasing friction of
flow. The loss through incomplete ex-

October 31. 1911

POWER

661

pansion is but slightly influenced by the
temperature. The thermodynamic effi-
ciency reaches its highest value with a
temperature of about 660 degrees.

Among the losses in the low-pressure

J

V;

V,

JV^

'■i. 1

-"■'^v.

Fic. 6. Showing Detrimental Effect

OF Unit Surfaces for the Uniflow

Cylinder

cylinder the greatest is that due to in-
complete expansion.

Nature of the So Called Uniflow
System

The heat exchange between the steam
and the cylinder walls, the chief source
of loss in reciprocating engines, grows
per unit of area with the greater time of
contact, with the greater temperature dif-
ferences between the steam and the walls,
and with the force of flow and the whirl
of the steam. The injurious effect is
greatest for those surface areas which
are in live-steam contact throughout a
re^'olution and which, moreover, are ex-
posed to the greatest temperature differ-
ences of entering and outgoing steam.
Such are those of the ports and steam
passages and of the heads and piston. Of
the greatest effect on heat loss is the
condition whether the steam retains its
superheat or becomes saturated even
during expansion. With this in view cyl-
inders operating under similar conditions
can be compared with reference to the
loss effect of the surfaces, though a

Fig. 7. Un

DER WITH Deep

Piston
comparison between a single cylinder and
a compound engine is not possible on
account of the other differences of steam
density, etc. The economy value of the
so called uniflow design is based mainly
on the fact that the injurious surfaces of

the exhaust passages in the end of the
cylinder disappear.

In Fig. 6 is shown the detrimental ef-
fect of unit surfaces for the uniflow cyl-
inder. The losses apportioned to the cyl-
inder walls through the unit surfaces Vi
— Fs are very small. If account is taken
of the important influence of the steam
flow on the heat loss through the walls,
especially in the passages, the advantage
of separating the exhaust channels from
the live-steam space becomes more ap-
parent.

Heating the Cylinder Heads

The extent of the clearance is in no
way important as to results. This is
proved by the favorable results in at-
mospheric-exhaust operation with from
10 to 12 per cent, clearance. The detri-
ment of surfaces depends, apart from
their own extent, on that of the tem-
perature differences, and particularly on
the continuance and force of the steam
flow. Consideration of the latter leads
to the demand for the highest possible
temperature for the steam-space walls

high compression of about 90 per cent,
of the stroke. This high compression is
a necessary evil of this design.

The disadvantages of high compression
are materially lessened through the high

Fig. 8. Uniflow Cylinder with Ex-
haust Ports Outside of Steam Space

nearest the incoming steam and the low-
est possible for the walls of the outlet
passages; a demand which, in part, is
met by heating the cylinder head with
live steam. From the heated cylinder
heads to the exhaust-cooled mid-cylinder
point a diminution of wall temperature
takes place in uniform direction with the
steam flow. The uniformity of direction
is of secondar>' import. A recognized
disadvantage of the uniflow cylinder. Fig.
7, is the low-temperature piston, because
of the excessive cooling of its surfaces
by the escaping exhaust, especially at
the moment of release, and because the
piston surfaces are open to condenser
pressure through 90 per cent, of the
stroke. This effect, though, in view of
the advantages offered by the location of
the exhaust ports outside of the steam
space, must not be overestimated. With
a short piston, such as is shown in Fig.
H, this is largely avoided, although a
valve is needed to govern the steam re-
lease. Such a design has the further ad-
vantage that the compression can be less-
ened some 60 per cent.

The uniflnw cylinder shown in Fig. 7,
with main piston release, is tied to a

Temperature. Degrees fohrenhelt

Fig. 9. Steam Consumption and Heat

Distribution of Uniflow Engine at

Initial Pressure of 220 Pounds

and Terminal Pressure of 13

Pounds

temperature of the surfaces of the heads
and inlet passages. The means toward
increasing the cylinder-wall temperature
is the heating and not the high compres-
sion. It seems useless, by means of high
compression, to produce temperatures
which lie far above that of the incoming
steam and through such temperatures to
obtain surface heating because the heat
transfer from the steam to the cylinder
walls during compression contradicts the
efforts toward an adiabatic curve.

8 8 Wi lU 133 147 16.? n.6
**"' Termmol Pressure. Pounds p*r Sq In Abs

Fic. 10. Showing Steam Consumption
Dependent Upon Terminal Pressure

The cylinder shown in Fig. 8 was con-
structed for high superheat and for that
reason was wholly unprovided with any
jacket heating. The tests with saturated
steam and moderate superheating arc of
scientific value because by comparison

POWER

October 31. 1911

with the results from such engines as are
provided with jacketing and head heat-
ing the influence of superheating is
shown.

Fig. 9 shows the steam consumption
and heat distribution of a uniflow en-
gine as dependent upon the temperature
at an initial pressure of 220 pounds and
a terminal pressure of about 13 pounds
absolute.

Fig. 10 shows the steam consumption
as dependent on the terminal pressure
with a boiler pressure of 220 pounds and
a vacuum of about 27 inches. The most
favorable steam consumption per indi-
cated horsepower-hour is reached with a
terminal pressure between 10 and 12
pounds.

From the flat path of the curve of
steam consumption per indicated horse-
power-hour with a terminal pressure be-
tween 8 and 17 pounds, and by compari-
son with Fig. 1 it follows that the uni-
flow engine utilizes expansion less favor-
ably than does the compound engine.
This is particularly so in the absence of
head heating. There exists a balance be-
tween the losses due to heat interchange
and to incomplete expansion which is to
be considered as a thermal deficiency
of the uniflow engine.

The behavior with free exhaust is the
same as when condensing. The most
favorable steam consumption per indi-
cated horsepower-hour is reached with
a terminal pressure of about 24 pounds
absolute. With a terminal pressure of
34 pounds per square inch the consump-
tion is about the same.

A set of comparative tests showed a
saving in steam consumption of about
27 per cent, through running condensing
with a regular compound engine, whereas
with the uniflow engine, utilizing about
60 per cent, compression, the saving due
to condensing amounted to only 18 per
cent.

There is not much difference between
the steam consumption of the uniflow en-
gine and the ordinary single-cylinder en-
gine with jacketed heads and head-con-
tained distribution valves.

Referred to the effective horsepower,
the consumption figures are a measure
of comparative economy as between the
compound and uniflow engines, where-
fore the mechanical efficiency must not
remain unconsidered. With free exhaust
this is of still higher importance.

Conclusion

With compound working, the highest
steam temperatures are proved to be ad-
vantageous. Through superheating, ex-
pansion is used to better advantage in
that the terminal pressure is advantage-
ously smaller as the superheat is greater.
The losses occurring in the high-pres-
sure cylinder increase the theoretical
work capacity and the low-pressure cyl-

inder efficiency; hence the loss through
heat interchange, referred to the com-
bined cylinders, is very small and be-
comes even smaller as the arithmetical
mean of the respective losses in the in-
dividual cylinders becomes less.

The economically favorable load for
the compound engine corresponds with
a terminal pressure of about 9.5 pounds
absolute, as against one of about 14.7
pounds for the uniflow engine.

In connection with the lesser expansion
in the uniflow cylinder is the result that
high superheating is of much less value.
The object of superheating is accom-
plished when the steam leaves the cylin-
der in a dry, saturated condition; there-
fore, with a lesser expansion, less super-
heating suffices.

The greatest thermal advantage reached
in the unifiow engine is that the exhaust
passages are remote from the heads, but
the flow direction is of little significance.

Notwithstanding its thermal advantage,
the uniflow engine does not equal the
compound engine in heat utilization. With
the uniflow cylinder, superheating is in-
dispensable, but high superheat seems

back pressure, the uniflow engine could
be improved.

The appearance of the uniflow engine
has affected steam-engine building in an
active and fruitful manner and has hap-
pily encouraged efforts toward a further
development of steam power.

A Practical Pow er Plant
Oiling System

By Frank S. Bunker

Both gravity and pressure oiling systems
are in general use and differ only in that
in the one the pressure is furnished by
gravity and in the other by pumps. By
proper pipe arrangement the two systems
may be so combined as to secure the best
features of each. Both systems should
have primary filters, washing filters, set-
tling and storage tanks. Boiling tanks
are not a necessity, though very useful
for a thorough cleansing of the oil.

Nearly all power plants have basement
space which can be converted into the
necessary oil department. Fig. 1 shows
a typical arrangement. At some place
high enough to cause the desired gravity

^-^A. , ,1 ,"i

Fic. 1. Rlevation of Typical Oiling Syste.m

useless; the thermal and mechanical dis-
advantages of the uniflow engine based
on high compression become more evi-
dent the higher the back pressure, and in

pressure, and preferably under the roof
truss near the side wall of the building,
the main storage tank should be placed.
This should be large enough to hold suf-

free-exhaust operation, especially under ficient oil for 24 hours' run. To allow

October 31, 1911

POWER

663

for cleaning and repairs it should be
divided into two or more compartments,
as shown at the upper left of Fig. 1. The
inlet pipes should go over the top of the
tank at the end, turn down and extend to
within a few inches of the bottom. Owing
to the large amount of oil in the tank
the circulation is slow and allows foreign
matter which may be present to settle
to the bottom. The pipe arrangement
shown allows either end of the tank to
be used alone or the two used together,
and if for any reason one compartment
is to be emptied it may be accomplished
either to the engines or through a sep-
arate pipe.

Telli ale
It is always advisable that the man
in charge of the plant or watch may know
at a glance the amount of oil that is in
the tank. The string-and-tloat method
is antiquated and often unreliable and
dangerous. Fig. 2 illustrates an arrange-
ment which not only shows the amount
but commands attention with its alarms
and danger signals. As the oil lowers
in the tank the electric brush shifts from
one of the contact plates to another on
the vertical wooden rod and lights a
series of lamps on a board corresponding-
ly arranged. Where the oil reaches a level
indicating one-third of a tank left, an 8-
candlepower green lamp lights as a warn-
ing signal. A further lowering of the
oil lights a 32-candlepower red lamp,
and at a still lower level, say, 2 inches
above the top of the sediment pipe, a 16-
inch gong rings.

Filters
The oil as it leaves the engines is
more or less heated by contact with the
frictional surfaces as it carries in sus-
pension some grit and foreign matter.
The most of this foreign inatter is dust

way to the top and are surmounted with
sheet-steel pans or bo.xes. These pans
rest on felt gaskets to make them nearly
oil tight and that half of the bottom of
the pan which is away from the inflowing

Fic. 3. Cross-section of Storage Tank

oil is perforated. Baskets made of fine
wire mesh are placed in these boxes and
are filled with curled hair through which
the oil is strained. Leading away from
the tops of the division plates are curved
baffle plates which extend entirely across

Fic. 2. Suggestion for Filtih (

and mrit which has settled from the air.
This must be removed by filtration.

The first or primary filter. Fig. 3. con-
sists of a steel tank divided into four
or more compartments. The division

the filter and which allow the oil to sink
easily inm the main body without creat-
ing eddies, whirlpools and other disturb-
ances.

There should be two of these filters.

plates reach about three-quarters of the which may be used singly or in series.

An Air Keccivcr Explosion

Bv Robert E. Newco.mb

The writer is familiar with a power
plant consisting, in part, of an old two-
stage duplex belt-driven air compressor
and an air receiver; the air is com-
pressed to 80 pounds.

One afternoon the engineer was
startled by a terrific report followed by
a long and loud screech. The engineer
examined the air receiver, where the dis-
turbance seemed to be, and found that
the spring pop-safety valve had burst.
The compressor was stopped and a fur-
ther investigation was made, when it
was then noted that the lower section
of the receiver was a dull red and that
the bottom head had been distorted so
that the receiver stood some 2 inches
off from its foundation, excepting at the
center portion of the lower head.

A hurried investigation showed no
rupture in the air piping or the receiver.
The relief valve was then replaced and
the compressor started. Everything was
then apparently in good order, except
the receiver, which showed a few small
leaks at the joints of the bottom head
and shell. These joints were soon corked,
and, up to the present, no further evi-
dence of injury has appeared.

A mineral lard oil diluted with a large
percentage of kerosene had been used
during the previous winter with reniark-
abh good results, and as its use was con-
tinued into the warm weather, the mix-
ture undoubtedly caused the explosion.

In this case it is fortunate that the
relief valve was weak and burst, as
otherwise much greater damage would
probably have resulted as the pressure
must have risen almost instantly.

Without doubt, compressed air is the
safest kind of power and there is little
or no danger in storing it, but the in-
troduction of kerosene or gasolene into
the oil to clean the cylinder and valves
generally resuhs disastrously. A solution
of soft-soap and water is an excellent
cleanser for an air cylinder and may be
used without danger: it is even recom-
mended where high-grade oils are used.

As the washing effect possessed by
steam is lacking in air, it will be found
that oil remains much longer in an air
cylinder than in a steam cylinder; hence,
a surprisingly small quantity of good
oil will lubricate an air cylinder without
difficulty. Only the best oils of high
flash and fine test should be used and
they are the safest and most economical
in the long run.

A frequent cause of explosion in com-
rresscd-air discharge pipes and receivers
is an accumulation of carbon in the
pipes or of oil in the receiver. Oil should
be drawn off from all air receivers at
frequent intervals.

Another cause of air-compressor explo-
sions is the high temperature caused bv
the churning or continued recomprcssing
of the air when the discharge valves leak.

664

POWER

October 31, 1911

Induction Motor Repairs

By R. H. Fenkhausen

Removing Coils

There are two methods of holding
stator coils in place in use by the dif-
ferent makers. The best method and the

Fig. 12. Wedge Fastening

one almost universally used on modem
motors is shown in Fig. 12. Hard-fiber
wedges are driven into dovetailed grooves
in the teeth and not only hold the coil
firmly, but protect it from oil and chips
which may be drawn into the airgap by
the ventilating fans on the rotors. With
the other method, shown in Fig. 13, there
is no protection over the coil, which is
held in place by lashings of twine looped
around an insulated iron ring and each
coil in turn. This method is no longer
used except as an anchor to prevent
movement of the overhanging portions of
the coils in motors designed for very
severe ser\'ice; in such cases it is used
in addition to the wedges, and the loops
are at the extreme ends of the coils.
See Fig. 3. October 24 issue.

When a coil is to be removed, enougli
wedges must be driven out to allow the

FiG. 13. Coils Held by Lacings

coils under which it lies to be raised
clear of the core. The lacings, if any,
must also be cut for a corresponding
distance. The number of coils which
must be raised to allow the removal of
a damaged one, varies with the type of
winding from the extreme shown in Fig.
4, which allows removal of any coil with-
out disturbing the adjacent ones, to the
other extreme represented by a bipolar

diamond winding which necessitates rais-
ing half the entire winding.

Practically all windings except the con-
centric require the removal of all the
coils spanned by one pole, but as each
winding will be treated in its proper
place, no further distinction need be made
here.

After the lacings have been cut away
for the proper distance the end must

Fig. 14. Starting a Coil

be made fast (otherwise the entire circle
of coils will loosen up, as the lacing
is in one continuous piece) and all con-
nections between coils carefully un-
soldered.

The coils must never be pried out of
the slots with a screwdriver or trouble is
sure to ensue, especially if the coils are
old and brittle. The first coil is the
hardest to start, owing to lack of work-
ing space, so a little time must be given
to its removal. If a strip of "4-inch
linen tape be slipped under the upper
half of the coil at each end and tied
into a loop, a screwdriver mav be in-

serted in each loop in turn and the coil
gradually raised from the slot, using a
small block for a fulcrum, as represented
in Fig. 14. The tape sling should be as
close to the stator core as possible in
order that no bending will occur if the
coil is tight in the center of the slot.

Fig. 15. A Safe Coil Pry

.-Xfter the first upper coil is dislodged
•':ere is room on one side of the next one
hich may be used for the insertion of a
coil iron of the form illustrated in Fig.
15. In making this iron great care must
be used to round all corners and edges
well in order that no damage will be done
to the coils in prying them out of the
slots. After the top parts of a number
of coils equal to the pitch have been
raised, the lower half of coil one is ex-

FiG. 16. Order of Re.moval

posed and may be removed from the
slot as shown in Fig. 16 and repaired.
If more than one coil must be removed
it is, of course, necessar>" to remove them
in a direction corresponding to the arrow
in Fig. 16 or else more top coils will
have to be raised to gain access to the
lower halves. It is therefore necessao'
to begin the raising of the top coils at
the proper place in the winding.

Ocober 31. 1911

POWER

665

Coil Repairs
After removing the damaged coil or
coils they should be carefully washed in
gasolene and given a minute inspection
to determine whether they can be re-
paired or not. It will be found as a
general rule that only one or two turns
of the coil have been damaged and new

Fig. 17.

Fig. 18.

wire may be spliced in to replace that
burned off or pitted.

As the space in the slots is limited,
it is not practicable to join the wire
in that part of the coil which lies within
a slot. The taping must be removed
as shown in Fig. 17 from a to b and a
new piece of cotton-covered magnet wire
cut to the exact length to fit neatly be-
tween the cut ends. A small sleeve con-
nector of thin sheet copper must be made
for each joint and rolled up to fit the
wire, as illustrated in Fig. 18, the edges
being beveled to protect the taping from
being cut while driving the coil into
place. All of the wire ends and both
connectors must next be thoroughly
tinned and a piece of cotton sleeving long
enough to cover the joint must be slipped
on each end of the new wire and pushed
back out of the way. The wire must
then be bent to conform exactly to the
shape of the coil, the copper connectors
slipped on, and the joints thoroughly
soldered, care being used that no acid is
present in the flux used. After the solder
has set, the joints must be carefully in-
spected for sharp projections of solder

Fic. 19. Finger Plate

which would be liable to puncture the
insulation; if none is found, the sleeving
may be drawn into place and stretched
tightly each way so that it will fit the
joint snugly. A coat of orange shellac
or Insulating varnish should be applied
to the repair and when dry, the taping
replaced in the original condition. A
coat of varnish should then be applied to
the entire coil, after which if may be
replaced in the stator.

Before the coil is replaced, however,
the slot must be carefully inspected for
high laminations or lumps of copper
burned into the iron by the ground. If
this precaution is neglected, the coil will
be almost certain to be grounded as soon
as It is driven into the slot, as the in-
sulation will be cut open by the rough
places should any exist.

If the entire stator winding appears to
be in bad shape and the coils are brittle
and bear evidence of having been over-
heated at some time, the only safe pro-
cedure is to remove the entire set of
coils from the slots for inspection, be-
cause the operation of raising the "throw"
coils to enable the faulty coil to be re-
moved is sure to crack the brittle taping
on the end connections. These cracks
will leave openings for the entrance of
oil and moisture which will cause the
destruction of the winding after a while.

After the coils have been washed in
gasolene, a dozen should be selected at
random from the lot and bent slightly
to test the insulation. If it appears brittle,
slit the taping off the coils with a sharp
knife, taking care to hold the knife at
such an angle that the cotton covering
on the wire will not be injured. The

and other parts of the coil lying outside
the slots are unprotected, and are liable
to damage both by careless oiling, and
from accidental blows. The only ad-
vantages of this method are its cheapness

Fig. 20. Unsupported Teeth

cotton should be tested with a knife and
if it is not charred and resists an at-
tempt to scrape it off, the coils are worth
retaping and the balance of the lot may
be untaped.

If, however, the cotton covering ap-
pears to be charred or if the copper wire
is brittle owing to crystallization, it will
pay to scrap the whole winding, because
the labor of winding the new coils is
only about 2.'^ per cent, of the total labor
required for the repair and as the other
75 per cent, is consumed in removing
taping, insulating, replacing and recon-
necting the coils, it is poor policy to risk
.1 failure for the sake of saving the extra
labor involved in rewinding.

If the old coils seem to be in good
condition they should be dipped in in-
sulating varnish and thoroughly dried
before retaping.
Slot Insulation and Coil Insulation

There appears to be an irreconcilable
difference of opinion as to the relative
values of slot and coil insulation, and
before retaping the coils, the various
claims made by the advocates of both
methods should be considered. When
slot insulation alone is used, the coils
are wound on forms and dipped in an
insulating compound which holds Ihcm
in shape. All of the insulation is placed
in the slots in the form of treated linen
cells reinforced by thin fiber cells for
mcchanicil slrcnglh.

That part of the coil lying within slots
is, of course, amply protected, both by
the cells and the wedges which hold the
coils in place, but the end connections

Fig. 21. Short Coil Wedge

and its adaptability to partially closed
slots in which coils can be inserted one
layer at a time if untaped.

When coil insulation alone is used, all
of the insulation is placed on the coil
itself in the shape of several layers of
insulated paper under the external tap-
ing, and the coil may be placed in the
slot without any delay due to preparing
cells, etc. The disadvantages inherent
in this method are that the coil is very
stiff and hard to insert in the slots and
it is liable to damage by the sharp edges
of the core laminations while it is being
put into the slots.

By far the best method, in the opinion
of the writer, is a combination of the
two; one or two layers of taping are
wound on the coil and the balance of the
total required insulation is put in the

<-Cun!rq frfges
Fic. 22. Groove Cutter

slot. The taping on the coil enables it
to hold its shape during the operation of
inserting it in the slot and protects the
end connections from oil and mechanical
injury, at the same time leaving the coil
sufficiently flexible to enter the slots
readily.

The actual insulation of the coil is
mostly furnished by a treated cloth cell
which may be left long to facilitate en-
trance of ihc coil, and cut off and lapped
over under the slot wedge afterward.
The treated cloth is protected from sharp
corners and high laminations by t cell
of exiremch' iniigh and thin paper known
n» "Icatheroid" or "fishpapcr."

If the combination method is adopted,
a sample pair of cells should be made
up and a coil taped and pressed between

POWER

October 31. 1911

a pair of fiber jaws in a vise. If the
taped coil fits snugly in tfie cells, the
entire winding may be retaped and a
full set of cells made. If the coil is too
tight, the thickness of the leatheroid cell
must be reduced; if it is too loose, more
taping must be used on the coil.

.'^fier the coils are taped they must
be dipped in varnish and after the var-
nish has set they should be either dipped
in melted paraffin or thoroughly "dusted"
with talcum powder, in order to facilitate
the work of inserting them in the slots.

Preparing the Stator Frame

On stator frames not provided with
"finger plates" (see Fig. 19), the toothed
portions of the laminations are not under
compression and the teeth spread out at
the top, as shown in Fig. 20, leaving
spaces between the laminations which
take up oil. If the coils are not in good
condition they will absorb this oil by
capillar^ attraction, just as a lamp wick
absorbs illuminating oil. Therefore, be-

To Line

ToMofoi

Fig. 1. Mr. Young's Substitute for a

Double-throw Switch

fore inserting the insulating cells and
coils in the slots of the stator core, it
is a good plan to compress the laminated
teeth between clamps in order to expel
any excess oil. When the teeth are com-
pressed, the oil will be driven out and it
must be washed off with gasolene while
the teeth are under compression; other-
wise, some of it will be drawn back be-
tween the teeth as soon as they are re-
leased.

After the pressure is removed, the
laminations should be given a coat of
orange shellac mixed very thin so that it
will fill up the minute gaps between the
teeth and prevent the subsequent en-
trance of oil. When the shellac has dried,
the surplus must be scraped out of the
slots and a careful examination made for
rough places and high laminations, which
must be smoothed off with a fine file if
found.

The coils in some types of stator do
not fill up the entire depth of the slots,
and in such cases it is possible to sub-
stitute wedges for the rings and lacings
which hold the coils in place. It is not
practicable to use full-length wedges in
stators of this type, owing to the diffi-
culty of chipping the long grooves re-
quired ; but a short wedge about one inch
long may easily be driven into short

grooves chipped into each end of the
slot (Fig. 21) by means of the special
grooving chisel shown in Fig. 22.

LETTERS

Substitutes for Double Pole
Double Throw Switch

A few months ago W. S. Young de-
scribed the use of plugs and receptacles
as a substitute switch, arranged as in
Fig. 1. This does not appeal to me as
being very "fool proof." If the plugs were
in sockets 2 and 3, which would cause
the motor to run in one direction, and I
were called upon to run it in the opposite
direction, it would be just like me to
remove the plug in No. 2 and insert it in
No. 1 receptacle before removing the
plug from No. 3 receptacle, and then
my hair would be upended while the re-
sulting short-circuits blew the fuses.

The arrangement indicated by Fig. 2
appeals to me more strongly. Two re-

To Motor Armaftire

Better Arrangement

ceptacles stuck up in any old place are
connected to the power leads and two
plugs connected to the armature leads.
By simply removing the plugs and chang-
ing them, each to the other receptacle,
the direction of current will be changed
and there will be no chance of a short-
circuit.

^X'. Farbing.
Fort Ward. Wash.

Trouble w ith Alternators
I have two cross-compound Corliss en-
gines direct-connected to alternators run-
ning in parallel. The load is equally
divided between the engines and they both
run at the same speed. The indicator
diagrams are very satisfactory, showing
that each cylinder develops the same
power.

Nevertheless, there is an uneven hum-
ming sound produced by the alternators
and the ainmeter of one unit is ven,' un-
steady, swinging through 50 to 100 am-
peres. Recently I replaced one set of
badly worn collector rings and put the

carbons in first-class shape, but there
v.as only a slight change. There is no
hunting of either of the engines as I
tried every eighth of an inch, setting the
counterweight of the governor for in-
crease or decrease of speed.

Can arJybody tell the cause of the
trouble and suggest a remedy?

Charles Fox.

Bay Ridge. O.

Curinjr Oil Throwinj^

The journal oil rings on a 5-kilowatt

Nciter dynamo under my charge gave

considerable trouble by throwing the oil

Lccd^lrip

Strip of Tin Touching Oil Ring

out on the floor. Thinking that the oil
was too heavy I tried lighter oil, with the
same result. Then I cut a piece of sheet
lead the width of the oil-well opening
and a little longer and fastened a strip
of tin to it by a piece of copper wire
so that the free end of the tin strip would
just touch the oil ring, as shown in the
sketch. The tin gathered the oil off the
outside of the ring and dropped it on the
shaft; it also retarded the motion of the
ring. Since then I have not been troubled
with hot boxes or oil on the floor.

C. C. Long.
Leesburg, Fla.

Sparking Commutator
Our tix6'..-inch single-acting ammonia
compressor is driven through a Morse
chain by a 7 '/j -horsepower shunt- wound
motor running at 155 revolutions per
minute. The head pressure on the com-
pressor is 160 pounds and the back pres-
sure 25 pounds. The motor takes from
2(1 to 29 amperes and 220 volts and is
rated at 30 amperes.

The commutator sparks very badly and
the whole motor runs very warm. The
brushes have been shifted, the commu-
tator sandpapered and turned down and
the brush tension adjusted. In two hours
after starting, the commutator sparks
as badly as before. I should like to
know the cause of the sparking. Does
the action of the single-acting compressor
have anything to do with it? The ma-
chine runs 15 hours a day and is located
in a damp place close to the brine pump
and suction line. Would a compound-
wound motor give better service in this
case than a shunt-wound motor?

,1. C. Hawkins.
Hyattsville, Md.

October 31, 1911

P O W E R

667

Heatini^ a Shop with Engine
jacket Water
By F. B. Hays
In a small shop operated by a gas or
gasolene engine considerable expense
can be saved in winter by utilizing the
cooling water from the engine for heat-
ing purposes. The method employed
Is shown in Fig. 1, where A is
the jacket-water outlet pipe, B and C
the heating coils, and D the cooling-water
return pipe. The pipes £ and F are the
circulating pipes connecting the engine
with the regular cooling tank. Valves
are provided to control all of the pipes.

half of this is available for heating.
Multiplying this quantity (1500) by the
brake horsepower and dividing by the
number of B.t.u. required per hour to
heat 1 cubic foot of free air from 20 to

SJ.l^»>- v,s

-jynt

~i-m^

^

Pig. 1. Plan of Engine Roo.m, Showing Piping

To secure the most efficient operation
of the system, the coils and piping should
he arranged as shown in Fig. 2. as this
arrangement gives better circulation than
when the coils are placed on the same
level.

If the volume of water passing through
the heating coils be regulated by the
valves in the supply and return pipes
the temperature of the room being heated
may be varied to suit the weather condi-
tions. If must be remembered, however,
that when these valves are partially
closed, the valves in the pipes £ and F
must be opened an equal amount to al-
low the engine to receive the required
volume of cooling wafer.

The amount of space that the system
will heat depends, of course, upon the
amount of cooling water passed through
the engine jacket, and the power and effi-
ciency of the engine. Under ordinary
conditions the quantify of heat carried
away per hour by the cooling water is
from 2000 to 4000 B.I u. per brake horse-
power. A fair average is .VX)0 B f.u. per
brake horsepower-hour and about one-

75 degrees Fahrenheit for ordinary
climates (or from — 25 to 75 degrees
for cold climates) gives the number of
cubic feet which the svstcm will heat.

heating and ventilating, and will var\
somewhat with the construction and ex-
posure of the building.

The heating coils should not be built
haphazardly, but should be figured out
beforehand by the use of some of the
simple formulas found in books and cata-
logs on heating and ventilatio"

Practical Points in the Opera

tion of Diesel Engines

By Hiram R. Low

For some time articles have appeared
in the columns of Pow er, relating to the
Diesel engine, its good and bad points,
its operation under various conditions,
etc. The writer, having had considerable
experience with this type of engine, is
led to believe that a few points picked
up in his experience might be of con-
siderable benefit to some other readei^
who may be called upon to run a Diesel
outfit. First of all, let me say that I
can heartily agree with W. F, Caton,
who says that the makers of this en-
gine make a grave mistake in claiming
that the operation of their engine re-
quires only cheap help; if there is any
engine that calls for close and intelli-
gent attention, it is this same Diesel en-
gine, if good results are to be obtained.
With a Diesel installation properly
looked after, good results are readily ob-
tained.

In some respects this engine is a won-
der; one of the astonishing things about
it (to anyone accustomed only to other
engines) is that it can be started and

Arrangement of On

AND Piping to Segiire Conn Circulation
Of VCater

The number of B.t.u. required to heal I
cubic fool nf air through the required
number of degrees of temperature can
be obtained from any standard book on

brought immediately into commission
without any previous warming up or
other preparatory work, and without any
apparent harmful effects, even when the

POWER

October 31, 1911

liermometer stands below zero and
everything about the machine is dead
;old. Neither does it seem to mal<e any
difference in the operation of the engine
whether it is a cold day in winter or an
extremely hot one in summer, notwith
standing that it is only pure air heated
by Compression that is depended upon
for the combustion of the fuel oil.

Many of the writers who have had
something to say regarding the Diesel
engine agree that it will run well if the
valves are tight and kept free from car-
bon. There is almost always an "if"
about engineering, and right here is
where cheap help doesn't fit the Diesel
engine. If the carbon is kept from' form-
ing, the battle is more than half
won.

It is well known that an overload will
cause a smoky exhaust, accompanied by
deposits on the piston, piston rings and
both admission and exhaust valves, but
not all operators understand why it does
so. The reason is that the cylinderful
of air contains just so much oxygen and
this amount of oxygen is sufficient for
the complete combustion of just so much
oil and no more. When the engine is
running at its rated load, this quantity of
oil is being fed and the exhaust should
be clear. If an overload is put on the
engine, the governor causes the pump
to increase its delivery of fuel and the
result is that more oil is pumped in than
the oxygen in the cylinder can burn com-
pletely; consequently some of the car-
bon in the oil is partly burned, thereby
producing smoke. There is no clearer
illustration of this than a common kero-
sene lamp. The wick is the oil pump
and when it is turned up to the proper
hight there is a clear light (without
smoke) for the reason that there is a
sufficient guantity of air being admitted
through the burner to completely con-
sume the vaporized oil. Now, "over-
load" the lamp, that is, turn up the wick
a little further and thereby increase the
supply of oil; there is no more air than
before, so that the excess oil cannot be
burned. The result is that part of the
oil supplied is completely burned and
part is partially burned, the latter pro-
ducing smoke.

An overload can be imposed on one or
more Diesel engine cylinders by a clogged
atomizer in the fuel-valve bracket of an-
other cylinder. The clogged atomizer
admits little or no oil to the correspond-
ing cylinder, which therefore cannot do
its share of the work; the work of the
other cylinders may thereby be increased
beyond their share of the full load, pro-
ducing incomplete combustion and its
consequent smoke. The only remedy in
this case is to take the faulty atomizer
apart and either thoroughly wash it out
, with gasolene or kerosene and run a fine
wire through the holes, or put in a new
one. Another cause of carbon deposit
is a leaky needle valve. This will admit

oil to the cylinder constantly, the
warmth within the cylinder distils it, and
the rising temperature during the com-
pression stroke causes it to become
heated enough to smoke. Usually a few
minutes spent in grinding in the needle
valve will cure it. Sometimes, however,
the needle valve will leak from another
cause which is due to expansion of the
"fuel rod" connected to the bell crank
that operates the needle valve. Expan-
sion of this rod will cause the bell-crank
end or tappet to press against the fiber .
on the needle-valve body and hold it off
just enough to leak. There is consider-
able pressure on the injection line under
running conditions, and a small leak here
shows up amazingly.

Other causes of smoke are leaky pis-
ton rings, which of course cut down the
pressure and temperature of compression
(this can usually be identified by the
smoke coming out of the crank-case
vent) ; leaky admission valves, exhaust
valves or safety valves, and on the one-
cylinder engine, a leaky starting valve.

The starting valve should be well
looked after and the stem kept free from
carbon with liberal doses of kerosene.
The writer knew a case where the whole
starting line of piping was ripped off by
an explosion backing up through a stuck
starting valve. Care should be exercised
lest too much oil is fed to the compres-
sor, on this account.

Another prolific cause of smoke, and
at the same time a loss of power, is late
admission of fuel. A good way to find
out at which point in the stroke the fuel
valve is opening is to slowly bar the en-
gine around until the crank of the cylin-
der fed by the suspected pump is within
a short distance of the top center. Hav-
ing previously lifted the admission pipe
out of its flange so as to be able to hear
the least escape of air, turn on the in-
jection pressure from the bottles and bar
around until the valve just "cracks,"
when the pressure can plainly be heard
going into the cylinder. This should oc-
cur when the main crank is 1 per cent,
ahead of dead center, and the center of
the roller that runs on the fuel cam
should just be in line with the opening
line which is plainly marked on the cam.
If it is not in this position it can be put
there very readily by shifting the cam
nose either ahead or back, as occasion
requires. It should be remembered, in
this connection, that too early an open-
ing of the fuel valve will cause a very
pronounced pound, owing to premature
ignition. Late admission will cause
smoke and loss of power owing to the
fact that the air in the cylinder is be-
coming rapidly cooled by expansion and,
also, the piston is rapidly moving away
from the head when ignition occurs, giv-
ing somewhat the same effect that late
admission would on a steam engine.

Should the injection pressure become
too low, that also will cause smoke; if

it is too high, a pound will be noticed.
There is a happy medium as to the
proper injection pressure to carry under
different loads and when found it will
go a long way toward the smooth run-
ning of the engine.

CORRESPONDENCE

A Diesel Engine Diagram for

Comment

The accompanying indicator diagram
was taken from one cylinder of a Diesel
engine driving a 300-kilowatt generator.
The load was 275 kilowatts and the speed
164 revolutions per minute at the time
the diagram was taken. The engine is a
twin unit, each half of which has three

Haximum Cage Pressure, 540 lb.
Mean Effective Pressure, GOIb.

Diagram from Diesel Engine

cylinders 16x24 inches. I will appreciate
comments on the diagram in Power by
other readers who have had experience
with Diesel engines.

William R. Caton.
Southbridge, Mass.

Coal Consumption of Pro-
ducer Plant

The gas engine and producer plant of
which I have charge consists of one 100-
horsepower engine and producer and one
50-horsepower engine and producer, the
engines being direct connected to elec-
tric generators. The larger unit is al-
ways in service, the other being kept in
reserve. The load averages 480 kilowatt-
hours for 9'S hours per day, or at about
the same rate for 54 hours per week, the
engine being shut down the remainder
of the time. However, the fire in the
producer is never out. Buckwheat coal
is used and some of it is of a poor
quality.

I would like to hear from some engi-
neers having had practical experience
with producer-gas plants as to what the
coal bill ought to be for this load and
load factor. The engines are in good
condition generally, although the pistons
leak some. Would it be possible to save
coal by speeding the engine above its
present speed of 200 revolutions per
minute? What temperature should the
gas have when it enters the engine, and
what should be the temperature of the
water from the scrubber where the gas
goes direct to the engine, as in suction-
producer installations?

A. A. Rice.

Chicago. 111.

October 31. 1P11

P O \X' E R

Turbine Foundations

A properly lined and balanced turbine
should not require that the base be en-
tirely surrounded by concrete, leaving
barely room to get at the step-bearing
bolts.

One turbine was installed on the floor,
which was supported by I-beams; and as
the turbine did not operate satisfac-
torily, of course the cause was attributed
to the foundation. But when the troubles
in the turbine were remedied there was
no further occasion to blame the founda-
tion.

The foundation was far from ideal,
however; the I-beams were tied in the
walls and fastened to them were steam
pipes running to trip hammers in the
blacksmith shop.

With the turbine stopped, the jar from
the trip hammer could be felt on top of
the shaft and the deflection of the shaft
indicator was 0.005 to 0.008 inch when
the turbine was stopped.

Notwithstanding all this, after the ma-
chine was fixed it ran smoothly.

G. Smith.

Lynn. Mass.

"Differential" Chain Block

It is probable that all who read this
are familiar with the simple "differential"
chain block, which consists of two
pocketed chain sheaves at the top, a
single sheave at the bottom and a con-
tinuous chain for operating. The yokes
and the hooks must, of course, be in-
cluded for sustaining the whole and
carr>'ing the load.

With the 1-ton block, as ordinarily con-
structed, the operator must pull 30 feet
of chain in order to hoist the load 1 foot;
in other words, the block has a velocity
ratio of 30 to I, and were it not for
friction — which, in spite of the simplicity
of the mechanism, generally amounts to
over 60 per cent, of the power applied —
the weight lifted would be .30 times the
pull exerted by the operator. Having
hoisted the load I foot, return it to its
original position; to do so. but 28 feet of
chain will have to be pulled. What has
changed the ratio from 30 to 1 to 28 to
1. and what has become of the remaining
2 feet of chain?

As is almost invariably the case with
.1 paradox, the solution of the problem
i^ easy — too easy to be considered a test
of the reader's mechanical ability unless
the time required to answer the question
be considered. Nevertheless, a good
many high-class engineers have been

puzzled for a time by the above state-
ment.

The solution may also lead to a sim-
ple rule for determining the velocity
ratio of a block of this type without
resorting to actual measurements of any
kind.

H. M. Phillips.

Pittsburg. Penn.

FintlinL!; Flash Point of Oil

Much discussion has arisen as to the
proper point to which oil should be
heated before being fed to oil bumers.
The first thing to do is to find the flash
point and then heat the oil within 5 or 10
degrees of the flashing point. The oil
will flow through the pipes more read-
ily when hot than when cold and will
burn better. Heating the oil will also
tend to precipitate what moisture it con-
tains to the bottom of the oil tank, from
which it may be removed by pumping.
A simple method for ascertaining the

/

Apparatus Used in Finding Flash
Point of Oil

flash point is given herewith. The ."p-
paratiis required is a Fahrenheit ther-
mometer reading to 300 degrees, a Sun-
sen burner tripod, a Bunsen burner, an
iron dish (sand bath I about as large as
a good-sized saucer and a copper cup
as per sketch.

Fill the sand bath two-thirds full of
common sand and place if on the tripod.
Then cover the sand bath with a piece of
sheet asbestos, leaving a hole in the cen-
ter of the sheet to admit the copper cup.
which has been filled with oil to the
level shown in the sketch, allowing the
bottom of the cup to rest on the sand.
Then take a small piece of sheet asbes-
tos H which has a small hole C cut,

ihrough which the thermometer is in-
serted, and cover the top of the copper
cup with it. Insert the thermometer
through the hole C until the bulb is im-
mersed to one-half the depth of the oil
in the cup. This can be done by sus-
pending the thermometer with a piece of
string from some convenient nail. Now
place a flame under the sand bath and
heat it gently.

A Bunsen burner is best for this pur-
pose, but any small flame will answer.
The oil should show a rise in temperature
of from 5 degrees to 8 degrees a min-
ute. When the oil reaches 100 degrees
Fahrenheit, pass a small flame over an
opening in the corner above the surface
of the oil at every 2 degrees rise in tem-
perature until a small bluish flame ap-
pears on the surface of the oil. Note
the temperature at which this takes
place and call this temperature the flash
point of the oil.

If gas is available, a small piece of
glass tubing may be heated in the center
until soft and then drawn out to make a
jet. When inserted in a piece of rub-
ber tubing this makes an excellent way
of obtaining a small flame ( ' \ inch long)
to pass over the surface of the oil when
testing. The method described will give
the flashing point of the oil closely
enough to enable one to judge the point
at which to heat the oil.

William Pattern.

San Antonio. Texas.

Water Wrecked Lou Pressure
Cylinder

At three minutes past six o'clock on
Wednesday. September 27, the low-pres-
sure side of a cross-compound engine
was wrecked by a dose of water. As is
customary in some mills, the main en-
gine is kept running some few minutes
after the whistle blows to keep the lights
on, and enable the operators to get out
of the building.

This engine has been running for four
vears under the same general conditions
without a mishap of any kind. The vac-
uum is maintained on the engine with
a jet condenser which will not siphon
over, on account of having a lift of about
3 feel; as a matter of fact, there is a
pressure of ^.F< pounds shown by a gage
attached to the priming pipe. The prim-
ing pump is kept running during the
time the engine is in service.

The boiler house, containing thi^e up-
right boilers, is situated across the river
from the mill, the main steam line being

670

approximately 150 feet long. It is pro-
vided with an ample separator situated
within 10 feet of the high-pressure cyl-
inder. The separator and receiver are
both drained of condensation by traps
of ample size which have always worked
satisfactorily. The water used in the
boilers is taken from the river and is
quite dirty; at some seasons it contains
more or less chemicals from dyeing es-
tablishments located further up the river,
and the boilers had a tendency to prime.
The load was practically all off the en-
gin- at the time of the mishap, the cutoff
being so short that the receiver gage
showed but 3 pounds pressure.

Here is a case where everything was
seemingly the same as usual, and within
one minute of the time for shutting
down, the engine got a dose of water and
was wrecked.

I am of the opinion that the water did
not come from the condenser; where did
it come from? Power readers have
solved other problems put up to them and
I hope to read what the engineers who
have had experience with condensers
think caused the wreck.

H. R. Low .
iMoosup, Conn.

POWER

of the top, on each side of the joint, and
put pieces of string in the holes. When
the rings were in place the joint was
pulled together with the strings and tied.
Then there was no difficulty about the
rings staying in place.

F. X. GOKHE.

Cambridge. Mass.

Difficult Packing; Job

Owing to an accident to a vertical,
compound engine of the riding-cutoff
type, it had to have new valve stems, and
also new metallic packing. After the
engine had again been running a short
time the packing began to leak, and
gradually grew worse. It was found that
the new stems had been made of very
soft steel, and the new packing was so
hard that it wore a shoulder on the stem.
As the engine could not be spared for
some time, a makeshift soft packing was
used instead of the metallic packing.
First, an asbestos ring packing was used,
but it would only stay tight a few days
and then the packing would blow out.
Two cup-shaped rings had been used
at the bottom of the stuffing box and
one between the packing and the gland.
The engineer who had put in the soft
packing had taken these rings out and
had filled up the stuffing box with the
rings of soft packing, depending on the
expansion of the packing to keep it tight.
I replaced the cup rings and put three
rings of the soft packing betv.-een them.
When the gland was screwed up in place,
it forced the packing into the cups close
to the valve stem. As a result there
was no more trouble from leaky stems
for about eight weeks. There was very
little room to put in the packing without
disconnecting the stem from the cross-
head and taking off the gland, and it
was also difficult to keep the rings in
place until the gland could be pushed in
place.

I drilled a small hole through the rings
diagonally, from the side to the middle

Emergency Bearing Repair

Recently in a large power plant in
which I was one of the engineers, I came
up against an emergency, through the
sudden heating of one of the main out-
board bearings of a compound engine,
which was used for the lighting of the
works and a small town in the immedi-
ate neighborhood. There was a dupli-
cate set, but it was dismantled and un-
dergoing an extensive overhauling; con-
sequently the other engine was running
continuously night and day. It was some-
what overloaded, especially at night,
when the full load was on. Ordinarily both
engines were in operation from sunset
until 1 o'clock a.m.. when one was shut
down at the end of each run. Both en-
gines were fitted with sight-feed, auto-
matic lubrication; the oil. after having
passed through the bearings, was run
through a filter, and again circulated by
a small pump attached to the engine.

It is impossible to sa>- whether sand
or grit got into the bearing with the oil,
or whether the oil supply had ceased on
that particular bearing, but in any case
the engineer noticed smoke coming from

October 31, I9ii

at the ends of the bearing where the
metal could run out were closed with
red-lead putty faced with oiled paper.

The metal was then poured into the
lower bearing until it was filled level to
Its top. Strips of oiled paper were then
laid on each side to divide the metal in
the upper bearing from that in the lower,
and also to pack up the bearing suffi-
ciently. Metal was then poured into the
upper half of the bearing through the
oil hole; as soon as the metal set, the
oil hole was drilled out and an oil chan-
nel cut three-quarters the length of the
bearing. The oiled paper was removed,
the bearing adjusted, and the engine was
started up and the usual load put on it
without showing any signs of knock or
heating.

Although the time of stoppage was not
taken, I think I am safe in saying that
the time occupied in making this repair
did not exceed 30 minutes. For emer-
gencies, and indeed at other times, this
is a useful method for babbitting bear-
ings in place, but great care should be
used to see that everything touched by
the molten metal is quite dry and warm;
as pouring it upon any cold or damp
surface will cause it to spatter.

J. Creen.
Seattle, Wash.

Bricking Furnace

Furnace repairs are expensive and my
experience has shown that the design,
workmanship and materials are the

U-16 ■'-->■<

//-I?"

Onr Method of Building an .Arch

the bearing. The throttle was closed,
but not entirely, sufficient steam being
given to keep the engine turning to pre-
vent the shaft from being gripped.

An examination showed that the bab-
bitting had run out of the bearing and
that the shaft at that end was down.

The engine was at once stopped and
the bearing stripped, preparations being
made for a hurried repair. The 5-inch
shaft was gradually cooled by the appli-
cation of water-soaked waste ; and in the
meanwhile the old babbitt was chipped
out of the top and bottom halves of the
bearing, and a pot of white metal got in
readiness to run into the bearing. In
order to give the necessary clearance
when finished, and to prevent the metal
adhering to the shaft, a piece of writing
paper well greased was tied around the
journal. The shaft was then packed up
to its original level, and held firmlv in its
true position by wedges, and the spaces

cheapest when the best to be had are
used.

Boiler settings having large arches
cause the most trouble and are common-
ly found in large power plants.

Many large power stations use auto-
matic stokers with main and coking
arches, especially if soft coal is burned^
Furnaces of this type may fail from
a high rate of combustion, high furnace
temperature and from an inferior quality
of firebrick.

Poorly designed furnaces and poor
workmanship in building up the furnace
affect its period of service. Some of
these troubles can be partly overcome,
others cannot.

Where a high rate of combustion and
high furnace temperature are maintained,
any quality of firebrick will fail in time,
but if a low grade of brick is used it is
not worth the time and expense of put-
ting them in. Such a furnace should

October 31. 1011

have not less than 13'; inches of fire-
I brick lining and more would probably be

better and cheaper in the end.

When clinkers adhere to the side
walls they must be removed with the
slice bar or sledge. In breaking the
clinker off, portions of the firebrick are
removed each time and this soon
weakens the side wall. If the side
wall gives, the arch will either crack
or sag. If a side wall has 9 inches of
firebrick lining and the balance of the
wall is red brick, when the lining is gone
and the heat reaches the red brick they
crack and melt quickly. I have found it
cheaper and better to make the bridge-
wall and drum arches entirely of fire-
brick.

Patching up the side walls and joining
the new and old work under an arch is
not advisable as it is almost impossible
to make the work stand.

Any furnace should be heated gradual-
ly and cooled in the same manner; cold
drafts should not be allowed to pass
through the furnace while hot. and leak-
ing tubes on the hot brickwork and
arches should not be allowed. Avoiding
such conditions will largely prevent the
cracking and falling out of the brick at
the end and underside of the arch.

! have recently rebuilt 16 furnaces,
using the best grade of firebrick. The
arches were built up of block, as shown
in the accompanying sketch, of the same
quality as the brick.

In rebuilding a furnace and laying
the side walls all the old wall was re-
moved. The brick in the side w'alls were
uniform in size and quality, were dipped
in water and carefully set. The ends of
the arch blocks were dressed and rubbed
to fit before placing. As much as was
practical of the coking arch was laid of
blocks, of the same size as the main
arch. The balance of the coking arch
was made up of brick.

These Ifi arches have been in service
about nine months and they are in as
good condition as when rebuilt.

Previous to building the arches, stand-
ard brick were used, and they would sag
and fall in from two to six weeks. Some
of them were rebuilt three times within
the year. These arches have an 11-foot
span and 22-inch spring.

In the sketch is shown the construc-
tion on the arch I have successfully
employed. It is impracticable to build
one side of a battery at a time.

To rebuild a battery of this class costs
between SfiOC) and S80fl. including ma-
terial, labor, etc.

The loss of service of the boilers would
depend upon conditions and the num-
ber held as reserve units. To operate a
battery with fallen arches and bad set-
tings for any length of time causes losses
probably near the cost of the rebuilding.
W. J. Maxwell.

Indianapolis. Ind.

POWER
Troubles Due to Carelessness

.An industrious oiler, seeing that the
temporary shed which inclosed a new
500-kilowatt turbine was dirty, set to
work to clean it up, using large quan-
tities of water, but he forgot that the
condensing and exciter set was in the
cellar. As a result the condenser motor
was burned out and the turbine was run
with atmospheric exhaust. The night the
load came on I had the time of my life.
A gang of laborers was set to work saw-
ing wood so that steam could be held,
the boilers, to begin with, being heavily
overloaded. We got the motor fixed up
by working all night on the three coils
which had been burned out

On starting the motor 1 was unable
to prime the centrifugal pump as the
foot valve was stuck open. The only
thing to do was to rig a scaffold over the
well and haul out the 8-inch foot valve
and 20- foot suction pipe with the block
and tackle.

When that was fixed up I congratulated
myself that there was nothing else to go
wrong. I had not been running 30 min-
utes when the turbine began to slow
down, due to the fixed and moving blades
rubbing.

It seemed to be pure cussedness, but
the real reason was that the change from
atmospheric exhaust and superheated
steam to a vacuum was too much for the
disks, and they just warped.

H. Prew.

Montreal, Can.

Concrete Compounti Tank

I have in my plant a concrete box for
holding a boiler-compound solution which
was made as follows: A dry-goods box
of the proper dimensions was used for
the inside form. The outside form was

'^c-^-^

^^^T

4~

I

Concrete CoMPOUNn Tank

made of rough lumber and was about 4
inches larger than the inside box. The
bottom was put in first, and the inside
form was then placed inside of the out-
side form and the space was filled with
cement. The mixture was I of sand fo
1 of cement. Old pipe or iron wire can
be used to reinforce the box. After re-

671

moving the forms a wash of pure cement
and water was put on which added to
the appearance, and also made it w-ater
tight. When placed and piped as shown
in the sketch, it is far better than a tub
or a barrel sawed in half, as it will not
dr\' out and leak if neglected.

Harry E. Koffel.
Doylestown. Penn.

.\u\iliary Lubricator Con-
nection

When an engineer drains a lubricator
it is difficult to get it to start to feed at

Auxiliary Lubricator Connection

once with the ordinary method of con-
necting.

When an auxiliary pipe is attached to
a lubricator as shown, the condenser will
be filled while the engineer is filling the
lubricator. The reason for this is that
there is always some water passing
through from the steam pipe on the bot-
tom, which drops out at the first open-
ing. This connection can be put on with-
out changing the ordinary connections or
the head of the water.

Fred N. Livingston.

Seattle. Wash.

Huniinj; Fuel Oil

I received the following interesting let-
ter from H. P. Porter, of La Fundicicin,
Peru, on "Burning Fuel Oil." It may be
interesting to other engineers.

W. A. Hamlin.

Paola. Kan.

Perhaps it may be novel to hear from
a Kansan now working among the clouds,
H.OOn feel above the sea, in South
America.

I read your inquiry in Power (May 23
issue) about fuel oil. You may expect
fo evaporate about 10 to 15 pounds of
wafer from and at 212 degrees per pound
of crude petroleum. For your case as-
sume 12 pounds of water actual evapora-
tion. If your .'^.''-horsepower engine is
fully loaded, it will use prnhahlv not less
than .V) pounds of water per hor-scpnwer-

672

P O \v/ E R

October 31, 1911

hour or a total of 1650 pounds of water
per hour. To evaporate this quantity of
water will require 137 pounds of oil. A
barrel of 42 gallons should weigh about
320 pounds and last 2'^ hours if the
engine runs under full load.

I would recommend that you elevate
the oil-storage tank so as to get not less
than 10 feet of head. A pump would
help you in case you do not use an ele-
vated tank. A very small duplex pump
will do. It should have a relief valve
on the discharge so arranged that it will
run the oil back into the suction.

Do not heat the oil unless it is too
heavy to run.

H. P. Porter.

La Fundicion, Peru.

Pumping Engine Governor

A vertical, cross-compound, condensing
Corliss engine, direct connected to a cen-
trifugal pump, was recently installed in
the pumping station where I am em-
ployed. The speed of the engine is regu-
lated, on the high-pressure side, by a
governor, arranged as shown in the ac-
companying illustration. It is driven by
a chain drive and has a hand adjustment
for variable speed and is equipped with
an automatic safety stop which is on
the back side of the governor column
and is shown by the dotted circle it is
connected to the steam chest by the
pipe C.

When the throttle is opened and the
governor balls start to rise, the steam
pressure causes a lever to lean to one
side, which allows the governor to
drop to its lowest position in case
the chain should break or run off,
thereby throwing the safety cams in
position and preventing the steam valves
from opening. When the throttle is
closed and before the governor comes to
rest the lever moves to a vertical posi-
tion and comes in contact with a stud that
projects downward from a boss in the
slot and prevents the governor from
dropping to its lowest position. The low-
pressure cutoff adjustment is by hand. It
is the duty of this unit to pump water
from the river to the settling basins.

One night it was necessary to slow the
engine down as the basins were full and
the consumption small. When slo'-iig
down the wheel A was screwed dov.'n,
which compressed the spring D and
raised the governor balls higher, making
a shorter cutoff. It ran all right for a
short time when suddenly it speeded up.
I saw that the governor had stopped, and
when the engine was shut down it was
found that the chain had run off the
sprocket wheel on the shaft and the
safety stop had not operated. I found
that the spring was strong enough to
hold the governor balls up, which kept
the safety cams from coming into action.

The chain was put on and the engine

started and adjusted to run a little faster
and it gave no more trouble.

The reason why the engine did not run
away when the chain came off was that
as the speed increased the pump dis-
charged more water, which acted as an
automatic protection to the engine. This
would work only where the discharge
from the pump is open and with this de-
sign of pump.

If it had been pumping direct to the
discharge pressure the speed would have
increased more than the safety limit and
would probably have wrecked the en-
gine. The safety stop would operate
when the engine was running several
revolutions below its rated speed.

A belt tightener was made and fast-
ened to the ceiling of the gallery as
shown. This took the slack out of the
belt and kept it from swinging sidewise
and running off when the engine ran at
slow speeds.

At a certain pumping station there is
another unit used for the same purpose
but made by anothei firm. The governor
is the same with the exception of the
springs D and G, which are substituted
by a lever and weight with a threaded

Governor of Pu.mpinc Engine

rod and wheel H for adjusting the weight
on the lever and fastened to the bell
crank, also a counterweight, as shown by
the dotted outline.

With this arrangement the governor
could operate the safety cams at any
speed if the belt should run off the pul-
ley or break.

L.^WRENCE KjERULFF.

Kansas City, Mo.

Efficient Machinery

If the managers and engineers of
steam plants would make a careful in-
ventory of their present plants and put
down in black and white the many leaks
discovered, they would be surprised at
their frequency. One -eason why a new
plant shows such a high degree of econ-
omy is because there are no leaks.

There are many engines, pumps, gen-
erators, etc., running today which, if
repaired here, had a new valve there and
there was less "cussing," would show
higher economy. A central-station solicitor
is rarely successful in getting well kept
plants.

James W. Hockaday.

Granbury, Texas.

Avoided a Shutdown

One time on an excavation job I noticed
that the key was loose in the flywheel
of the large centrifugal pumping set and
that the flywheel was working off the end
of the shaft.

To stop the pump and drive in the
key meant time lost in priming the pump
with the facilities at hand, and mean-
while 50 men would be idle.

I picked up a heavy hammer and
found that by holding it against the shaft
the wheel could not work off any
further. I then called a man out of the
pit and stationed him at the hammer for
three hours and kept things going.

W. Candlish.

Edmonton, Canada.

Dry Back Marine Boiler

Would not the internally fired, dr\-
back marine type of stationary boiler be
suitable for small mill and electric-light
plants? In some of the small northern
plants containing but one boiler it is
sometimes necessary to keep the boiler
under steam for three months at a time
during a cold snap. In plants using the
usual return-tubular boiler there is con-
siderable danger of burning, especially
if it is necessary to use a boiler com-
pound.

With an internally fired boiler it would
be an easy matter to keep scale from
forming by feeding the necessary amount
of compound, and the sludge so formed
would settle under the furnaces away
from the heat. By using the blow off two or
three times a day it would be quite safe
to run three months without cleaning.

There must be a number of these boil-
ers in operation, and I dare say many of
the readers have considerable data on
the kind of service they are giving.

I would like to know if they give much
trouble, due to poor circulation, and if
these boilers would not be satisfactory
in sizes up to 150-horsepower or even
200-horsepower units when fitted with
corrugated furnaces.

Charles Fenwick.

Wapella, Sask., Can.

October 31, 1911

POWER

Hot Bearings

E. P. Baums, in the October 3 issue,
page 525, advocates cooling a hot bear-
ing with cylinder oil and water. I have
tried this, also graphite and oil, but ex-
perience on an air compressor has taught
me that lava soap and water is best for
cooling bearings.

A few days ago I had to work on an
air compressor and had to put some
liners in between a bronze bushing to
bring it in line. When 1 got it started it
ran hot to the smoking point in just a
few seconds. Cylinder oil was poured
on in a stream, but did little good, so I
stopped the compressor and cut up a
cake of lava soap in small blocks and
put them in the oil hole and then poured
a fine stream of water on the soap. In
a few minutes, by the aid of two buckets
of water, the bearing was running very
well; then soap and oil was used for a
little while, and thin ordinary machine
oil. Now it runs just as cool as any
bearing around the plant.

Daniel Gould.

Statesboro. Ga.

Massachusetts License Laws
and Examiners

In the August 1 issue, J. E. Levy,
under the heading "Massachusetts Li-
cense Laws and Examiners," criticizes
quite severely everybody and everything
in general connected with the licensing
department of his State. Since then sev-
eral letters commenting upon the one
referred to have been published. I have
been quite interested in them, especially
the one by Albert A. Smith on page 334
of the August 29 issue.

I believe Mr. Levy is correct in his
stated views and if those holding radical-
ly different ideas, with a few exceptions,
will take a little time and read between
the lines in Mr. Smith's letter, they will
discover some reasons for Mr. Levy's
declaration.

Mr. Smith is quite closely connected
with the examining board, he has been
present at a number of examinations and
it will be noted that those employed in
the same plant with him have had no
tiouble in securing first-class licenses
and that one of them has even been ap-
pointed inspector.

A little further along I find that he
had considerable to do with "House bill
'10," to which Mr. Levy makes objec-
tions. As Mr. Smith continues In his
explanation relative to committee hear-

Cojnmenf,

criticism, suggestions
and debate upon various
articles, fetters and edit-
orials which have ap-
peared in previous
issues

mgs, etc., it sounds good to the un-
initiated, but to those who have come
in close touch with such matters, the
impression he wishes to make is not last-
ing.

With all due respect to Mr. Smith and

Air Compressor Running
Under

The letters which have been published
on this subject appear to be rather at
variance. In the four illustrations each
machine is supposed to be running
counterclockwise, and the forces which
seem to me to act at the various cross-
heads are indicated by arrows pointing
vertically upward or downward as the
case may be. Fig. I represents a tandem
machine; Fig. 2, two machines facing
each other; Fig. 3, a twin machine, and
Fig. 4, a compressor driven by the motor
or belt pulley A.

I may be wrong; if so, I should ap-

DiACRAMs Showing Direction of FoRcrs Acting on Crossheabs

those connected with the licensing sys- prcciate a full and correct explanation

tern of Massachusetts. I smell fish' of where and why.

A. K. Vradhnbiroh. John S. Leese.

Albany, N. Y. Manchester, Eng.

674

POWER

October 31, 1911

Flywlieel Explosion at
West Berlin

I was much interested in W. E. Clnand-
ler's theory as to the cause of the re-
cent flywheel explosion at West Berlin.
According to Mr. Chandler, this wheel
was 16 feet in diameter, ran 86 revolu-
tions per minute and was a very good
casting. With good cast iron a tensile
strength of 18,000 pounds should be a
safe allowance. The wheel had a rim
joint, probably half way between spolces;
giving this joint an efficiency of 25 per
cent., and reduces the available tensile
strength to 4500 pounds per square inch.

Using the formula for stress, due to
centrifugal force, in a pulley rim the
bursting speed of the rim would be 256.6
levolutions per minute, or about three
times the proper speed of the engine.

A generator operated as a motor will
not run at as high speed as when driven
as a generator, but it will not make much
difference if we assume that it runs at
the same speed. The speed varies in-
versely as the field strength and to in-
crease the speed three times the field
strength must be divided by three.

Mr. Chandler was running two ma-
chines in parallel and doubtless both
machines were connected by an equalizer
between the armatures and the series
fields. The current driving the motor
must have come from the other machine
and its path would split between the
equalizer on one side and the series
field of No. 2 generator, the busbar and
the series field of No. 1 generator. This
split in the current will be in an inverse
ratio to the resistance of the two paths.
The resistance of the equalizer would
probably be very low and the most of the
current should go through it.

It looks very doubtful to me if under
these circumstances enough current
would pass through the series field to
reduce the field strength to one-third of
its proper value.

.\nother thing. i.~ the generator motored,
the only load it would have would be the
friction of the engine, and this would
not require a large current and the am-
pere turns in the series fields would be
proportionally less. For the same rea-
son, a circuit-breaker set at 550 am-
peres should not go out. although from
what I have seen of small railway power
plants on holidays I am surprised that
the breakers did not go during the day,
which, from Mr. Chandler's statement,
it seems they du' not.

-Mr. Chandler believes that the out-
board bearing was first torn from its
foundation and that the bursting speed
was not reached. With the generator
running as a motor, the only pull on the
belt and bearings is that required to run
the friction load of the engine. This
would be nothing compared to a load
of 500 amperes.

Where then was the strain to tear up

this bearing unless the flywheel was
badly out of balance ?-■ One would not
expect it in a plant running every day.

It is always much easier to find flaws
in the other fellow's theory than to ad-
vance one. With this type of governor,
if either one of the gears or the gov-
ernor pulley should get loose the balls
would drop to a position where steam
would be taken at full stroke. This would
cause the engine to speed up, take on
load until the circuit-breaker went out
and then — good night!

This might very well happen to a gov-
ernor with a very careful man, even if he
looked it over in the morning. Mr.
Chandler states that he went over the
wreck carefully, and I do not doubt him.

I very well realize that there is a run-
away now and then for which the engi-
neer is not so much to blame as some
would have us think. I would be pleased
to read the opinion of others regarding
Mr. Chandler's theory.

Lester Fitts.

West Fitchburg, .Mass.

Priming of Water Tube
Boilers

Referring to the article in the issue of
September 19 on "Priming of Water-
Tube Boilers," the author seems to have
dealt very fairly with the boilers men-
tioned in the article. While there are
a number of makes which were not men-

■2

^

^

DiACR.\.M OF Water Circulation in
Parker Boiler

tioned, they are all similar to those de-
scribed with the exception of the Parker
boiler, which operates on an entirely dif-
ferent principle from all others, and sev-
eral details of its construction and op-
eration are of especial interest in this
connection.

The tubes in the Parker boiler form
continuous elements to which the water
enters at one end and the steam is taken
from the other end through direct up-
casts to the drum. There is absolutely
no counterflow. The principle of the
boiler is shown diagrammatically in the
accompanying illustration.

The boiler has a large longitudinal
drum, divided by a horizontal diaphragm
into separate chambers for steam and
water. The upcasts discharge the steam
and unevaporated water at the rear of

the drum into the steam space in a hori-
zontal direction, and the steam travels
about 15 feet through this large passage
before reaching the steam nozzle. This
affords ample opportunity for the sep-
aration of the unevaporated water.

The anti-priming valve between the
steam and water chambers prevents
priming on a drop in pressure.

Parker Boiler Company.

Philadelphia, Penn.

Ihc Salesman and the
ineer

Engii

I was very much impressed with H.
M. Phillips' article, page 516 of the
October 3 issue, dealing with the above
heading. His statements are well known
facts to engineers who come in contact
with the salesman. Engineers who are
buyers, as a rule, "come from Mis-
souri," and if an article with which they
are unacquainted is offered to them, they
want to be shown. The salesman offer-
ing the article should be thoroughly
tamiliar with his goods in every par-
ticular and under all conditions of op-
eration. No one article will operate suc-
cessfully under all conditions and yet
there are salesmen who will talk one off
his feet trying to clinch an argument.
In my opinion this is poor policy. If a
question is asked regarding a certain
article as to how it will work under cer-
tain conditions and the salesman is en-
tirely ignorant of that condition, he will
rarely admit it frankly, but will con-
fidently guarantee success for his goods.
These verbal guarantees by some sales-
men are, and have been, the cause of a
loss of business to manufacturers.

In my own experience I have met a
number of salesmen, and in one plant
in particular they were all referred to
me as soon as they appeared. As I was
always on the lookout for anything which
would increase the efficiency of the plant,
I would listen to their introductory talk
which usually included a general de-
scription of goods, and in the case of
apparatus usually concluded with the
usual guarantee (verbally given) of a
saving of 10 per cent, in fuel.

Now it so happened that the plants
under my charge at the time were new,
and I had about as modem and uptodate
equipment as could be purchased; in
fact, no money had been spared to make
them second to none in economical op-
eration and efficiency, and the fact that
our daily coal consumption was con-
siderably under 2 pounds per horsepower
per hour, shows that they were success-
ful. When a salesman would talk about
a 10 per cent, saving in my coal bill, I
used to think he was up against a pretty
stiff proposition, and I would make my
proposal about as follows: "Well, de-
liver your apparatus, make any and all
changes while the plant is not running
(which would be at night or Sunday),

October 31. 1911

POWER

675

furnish all help and tools, have the
plant ready to operate at the regular
time, and, if the device is not success-
ful, remove the apparatus and leave
everything as found. 1 to be the judge.
I will draw a contract to that effect and
shall expect your firm to affix its sig-
nature. If the 10 per cent, saving is
made, my firm will agree to pay the price
of your machine and also the cost of
installation."

I do not know how many offers and
verbal guarantees I had. but I do know
that I never found one salesman who
would or could get his firm's signature
to my contract, and yet if a salesman
understood the conditions at a plant he
ought to be perfectly willing to do so. if
he and his firm really believe they can
do what they claim.

WiLLlA.M N. WlNC.

Brooklyn, N. Y.
Central versus Isolated Plant

Mr. Bailey hits the nail right on the
head in his letter. "Central versus Iso-
lated Plant," in the October 3 issue, as
1 have found by experience. The prin-
cipal difficulty, however, is to combat the
claims of the central-station agent, as
plant owners frequently seem to be
hypnotized into being far more interested
in purchasing from the central station
than in making the proper repairs to their
own plant. One of the reasons is the
same old story of miscellaneous items
of misleading character which are
brought up by the central-station agent,
similar to the profit ratio.

"Profit ratio" is an item taken up b',
the central-station agents to justify their
claim that they can furnish power cheaper
than the isolated plant can produce- it.
but it is se'dom brought forward except
where they cannot justif\- their claims
without it. It is very doubtful if cen-
tral stations could sell power at the pres-
ent rate if they took the same attitude
regarding profit ratio on their own non-
productive plant, as. for mstance. their
office and power-plant buildings, the dis-
tributing system and large purchases of
real estate upon which they propose to
build in the future. If they put upon
these nonproductive items a profit ratio
equivalent to the usual profit they obtain
from operation, the cost of the power to
them and to the user would be greatly
increased, as I pointed out in the April 25
issue, where I applied the same profit
ratio in a specific case. I have as yet
seen no argument advanced by the cen-
tral-station agent as to why this profit
ratio should not be applied to his own
case as well as to the isolated plant.

So far as an isolated plant handicap-
ping the manufacturer is concerned, it
is entirely a question of how well an iso-
lated plant is installed and with what
knowledge and accuracy the estimate of
the future possibilities of the business
are judged. Even under the conditions

of purchased power, there is a great
possibility that the manufacturer may
underestimate the possibilities of growth,
and thereby be greatly handicapped by
his location as well as by his power
contract.

In the installation of the electric drive
with power generated in the plant itself,
there is quite as good an opportunity
for growth as there is through purchased
power. The central station is in many
cases no better situated for furnishing
power at a low price than is the isolated
plant, unless its load factor is of a char-
acter which will allow the use of its ap-
paratus continuously for power purposes
and the two peaks, power and lighting,
not coming together.

If the central station has a load with
marked peaks, requiring a very large
amount of apparatus during the peak

will be paid for in exactly the same way
as will the profit on the desks, chairs,
and extra fittings for the factory and all
labor, not including productive labor, all
nonproductive items; in other words, it
will be paid for out of the general profits.
Hknr'i n. .Iackson.
Boston. Mass.

Shock. Absorber

In the September 19 number, H. Prew
is perfectly right when he says his idea
appears too simple to be new; it is very
old.

In the illustration is shown a shock
absorber, which consists of a plunger P
working through a water-packed stuffing
box G. Springs are arranged on top of
the plunger which may be of rubber, as
shown, or helical coil springs can be

Another Shock Absorber

load, and during the average load only a
compararively small an.ount, the interest,
maintenance and depreciation (profit
ratio) on this apparatus have to go into
the cost of power somewhere, resulting
in a large fixed charge which does not
enter into the isolated plant. During
'hose periods when the isolated plant
requires a small amount of power, which
may occur during slack times, the cost
of power per unit would increase, owing
to the increased fixed charges on the
smaller amount of power used; but I
notice that the rates on power furnished
by the central stations are so arranged
that under similar conditions the pur-
chaser has to pay a larger price per unit
for the smaller amount of power.

The question is, can the isolated plant,
by means of proper installation and op-
eration of apparatus, produce power at
a cheaper price than the central station
can supply it under similar conditions,
the isolated-plant power being figured
on the basis of no steam used for heat-
ing purposes, and the cost of power as
furnished by the central station being
figured as the cost of power plus the cost
of coal, water, labor aad fixed charges
on apparatus necessary for supplying the
heat'-'

For the isolated-plant power there
should be taken into account the interest
on the investment necessary for produc-
ing power, the maintenance and deprecia-
tion, the value of the room required for
producing this power as compared to
what it would be worth in case power
were purchased, and all operating
charges, no attention being paid as to
whether the power plant earned a profit
on its installation. The profit on this

used. The tie rods E hold the rubber
buffers B B in place. The idea is shown
and no description is necessary.

James E. Noble.
Toronto. Can.

(Joinji; over the Chief's Head
Some years ago the writer was firing
in a small light and power plant in which
it becaiTie necessary for the management
to reduce the operating expenses of the
system. In doing this, several men were
dispensed with and the salaries of the
superintendent, chief engineers and sev-
eral other men outside of the station
were reduced. The superintendent, chief
engineer and assistant engineer quit after
a reasonable notice. These vacancies
were filled by men from a large station
some distance away. The chief engi-
neer was a good talker on the subject of
steam engineering, but would not put
his knowledge into practice; the superin-
tendent was of the same caliber, but his
word could not be depended upon and
he tried to do everything in the very
cheapest and most haphazard way. The
supplies were of the very cheapest and
were not ordered until the last minute.

These circumstances made it very dif-
ficult to keep the plant in good running
order, so it became necessary to go over
the head of the superintendent to the
general manager for the ncccssani' sup-
plies. Later, a new superintendent came
on duty and it has never been necessary
to go over his head for anything rea-
sonable. Kortunalclv. not many incom-
petent men are on the list, and they
usuallv go the wrong way on the ladder.
C. E. NicH.
Morganlown. W Va.

676

POWER

October 31, 1911

Erosion of Pump Runner

In the October 3 issue of Power, page
526, John .lames shows a view of an
eroded pump runner with which he has
had some experience. I have found sim-
ilar cases of erosion on the worms of
screw pumps which have been in op-
eration for a long time, and have also
seen it on other parts of machinery in
direct contact with moving water.

I have attributed the erosion in spots
as being due to the difference in grain
of the metal used in making the moving
parts. In the cases referred to I have
found spots pitted out, leaving a large
ragged, honeycomb-like hole, and the
spots in the metal, when broken, showed
a coarse, sandy-like grain, but when it
was of fine grain it was not affected.

The coarse grain is so porous that the
action of water in motion and under
pressure works into the pores and
oxidizes the particles until they gradual-
ly wear away.

The proper remedy for such a case
would be to have the runners cast from
an even, fine-grained metal. Electrolysis,
as I understood it, would attack the sta-
tionary part as well as the runner.

L. M. Johnson.

Glenfield, Penn.

Jet Condensers

A good suggestion is offered by A. S.
Specht, on page 487 of the September
26 issue. He advocates tapping the ex-
haust pipe close to the low-pressure cyl-
inder and putting in a IK'-inch globe
valve as a vacuum-breaker to use should
occasion require. My choice is a cock
in place of a valve, as one move will
pull it wide open.

The incident related in the letter re-
ferred to, where the automatic vacuum-
breaker failed to work properly, calls to
mind a narrow escape from an engine
wreck which happened a little over a
year ago. The night engineer in a sta-
tion of 20,000 horsepower reported to
his relief when going off watch that he
had tried all vacuum-breakers (five in
number) and that two failed to work.

All five engines were running with jet
condensers of the twin-cylinder, walking-
beam type, the vacuum-breakers being
operated by the usual copper-ball float.
Upon examination of the two breakers
which would not work, in one case it was
found that the ball had collapsed, and
in the other it had split entirely around,
filled with water and sunk. The night
following the putting in of a new ball
float, the bonnet and yoke were blown off
the throttle valve of the very engine hav-
ing the sunken ball float. This accident
was owing to a defect in the dashpot of
the stop motion on this engine and the
valve was slammed down onto its seat
with sufficient force to contribute to the
effect as stated above.

The engine was of the heavy-duty type.

direct-connected, with a heavy generator
and flywheel. In order to stop the engine
from running away, it was necessary to
shut the main stop valve from the header
which carried 160 pounds pressure. The
layout of the piping was such that both
air pump and engine were supplied from
the same line; consequently, when the
main stop valve was closed the air pump
was stopped long before the engine,
which was running at 94 revolutions per
minute, normal speed. What would have
happened to that engine had not the vac-
uum-breaker been put into good working
condition may well be imagined.

H. R. Love.
Moosup, Conn.

Indiaitor Diagrams
In looking over some back numbers
of Power, I chanced upon the accom-
panying diagrams submitted by Mr. Fry-
ant, and originally published in the
November 1, 1910, number. A writer
in one of the later issues, in discussing
these diagrams, expresses the belief that
the peculiar expansion lines are due to
a grooved cylinder.

This is the reason given by Thomas
Pray in his "Twenty Years with the In-

DiAGRAM Showing Wavy Expansion
Line

dicator." Others have ascribed it to the
momentum of the indicator parts.

There is little doubt that the engine
from which the diagrams were taken is
one equipped with a main valve, single
ported on the face next to the cylinder
and triple ported on its other face, where
a triple-ported cutoff valve rides. The
main valve is actuated by a fixed ec-
centric, while the cutoff valve is actuated
by an eccentric under the control of a
governor. This governor is almost purely
of the centrifugal type and possesses
little stability with which to resist dis-
turbing influences set up by the action
of the valves.

The motions of these valves are so
correlated that when cutting off early in
the stroke the valves move in opposite
directions.

At the instant when cutoff occurs the
cutoff valve is moving at nearly its maxi-
mum velocity while the main valve is
either standing still or its motion is
just being reversed. After cutoff has
been performed the pressure in the cyl-
inder begins to fall by expansion, which
creates a difference of pressures acting
on the two sides of the cutoff valve, as

the port in the main valve is still open
to the cylinder. This unbalancing of the
cutoff valve causes it to stick firmly to
the face of the main valve and its motion
is momentarily arrested by reason of the
fact that the main valve is either at rest
or moving very slowly. This stoppage
of the cutoff valve puts a strain on its
eccentric which overcomes the stability
of the governor, causing the weights to
assume an orbit for a later cutoff and
when the weights agarn assume their
normal orbit they revolve the eccentric,
thus causing the cutoff valve to reopen
the ports and admit more steam to the
cylinder. I can distinguish five points of
cutoff on the diagrams shown herewith.
The admission of steam in this manner is
not only verj' wasteful, but it must seri-
ously affect the regulation of the engine.

I believe that this condition could, in
a measure, be overcome by putting a
drag on the cutoff eccentric, in the shape
of a double-acting dashpot, or by fasten-
ing to it a heavy inertia bar.

The first would overcome the tendency
by holding the eccentric in its proper
position until the critical point was
passed, while the second would acquire
momentum tending to pull the eccentric
against the resistance of the unbalanced
valves, but I doubt that either remedy
would entirely eliminate the trouble, as
the drag of the valve extends until the
cutoff of the main valve occurs and it will
become greater as expansion proceeds.

It is possible that more copious lubri-
cation would also tend to smoother oper-
ation of the cutoff valves. I would ad-
vise that Mr. Fryant try this, and, if it
has a beneficial effect, not to be saving
of his oil, as the saving at the coal pile
would in all probability more than pay
for the quantity required.

Charles F. Prescott.

Philadelphia, Penn.

Nerve

Judging from Mr. McEnaney's state-
ments in his letter in the August 29
issue, the engine unaer discussion must
have been of the Corliss type. If that
was the case, it would be interesting to
many engineers to know just how he was
able to reach and "hold up the blocks or
hooks" without losing a finger or two,
possibly a whole hand.

If the means adopted by Mr. McEnaney
were necessary in order to save the en-
gine, it is plainly evident that the gov-
ernor was not properly adjusted, as it
should have brought the engine to nor-
mal speed, by doing practically the same
thing as he did. If it would not do so
then an engine thus equipped would
have a very brief career as a rolling-mill
engine, for manifestly an engineer could
not "hold the blocks up" every time a
billet passed through the rolls.

Joseph Stewart.

Hamilton, O.

October 31, 1911

POWER

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(■ir;cui..iTio\ STATr:MK\T

Of thin i.isiic .30,000 copicn are i>riiile<l.

Xone sent free regularly, no returnx iron
Hews companies,
are live, net cin

back numbers, Fi^iu

Contents

New I*umping Station for London

Vibrations of the Indicator Pencil

Bell Crank Repair

Limitations of the Rope Iirivi-

Temperature Expansion lilagrain

Efliiency of Reciprocating Engines

A Practical Power Plant Olliug System..

An Air Receiver Exidoslon

Induction Motor Repairs

Substitutes for Double-pole Double-throw
Switch

Trouble with Alternators

Curing on Throwing

Sparking Commutator

Heating a Shop with Ensilnc .lacket
Water

Practical Points In the Opeiation of
iJlesel EnBines

A Diesel Knglne Diagram for Comment..

Coal Consumption of Producer Plant ....

Practical Letters :

Turbine Koundatlons .... "lufferen
Hal" Chain Block .... Klndlng Klash
Point of Dll. , . .Water Wreike<l I/iw
Pressure Cylinder .... Dllllcnil Pack-
ing .fob. . . . Kmergency Bcirlng Re-
I.nlr. . . .Bricking Eurnnce. . . ,Trou-
i.les Due to Cnnd'ssness. . . .(.'oncreie

r.impound Tiink \uxlllary Lubrl-

f.Ttor Coiine, lion .... Burning Fuel
Oil .... Pumping ICnglne tjovernor
... Efflcleni Machinery . . . . Avoldeil
n Shutdown. .. .Dry Back Marine
Boiler 'ifin

Discussion Leiters :

Hot Bearings. .. .MBSsnchusclls Li-
cense. Laws and Examiners. ... Air
Cnmprevxir Running I'nder. . . . Ely-
whe.l KT|do«lon nl West Berlin., .
Priming of Water Tills. BolbTs ...
The Snle«"inn and the Engineer ..
Central ver"ii" Isolnletl Plant....
Shork AtisorlxT. .. .filling over the
c|i|<f« Head. ... Erosion of Pump

Runner lei Condensers. . . .Indl

cnlor Diagrams. . . .Nervo B73

Editorials B77

Protecting the Conipreiinofs

Cooling Hot Llnuor

f*pening on Ammonia .Totnf

A Case of Frost

Porous P.rlne Plii>«

Fatal Fl.rivheel Explosion In Baltimore

Boiler Explorles iindpr HIrtewflIk

Rate Discrimination

The question of rate discrimination, al-
leged to be practised so extensively by
the New Yorlc Edison Company, now
promises to be brought to an issue,

.As announced by us at the time, sev-
eral months ago a petition bearing the
signatures of several hundred consumers
and backed by the representatives of
several prominent engineering societies,
was presented to the Public Service Com-
mission for consideration. This petition
charged that nearly one-half the electric
current sold by the New York Edison
Company in Manhattan and Bronx is
charged for at a rate over three hundred
per cent, greater than the average rated
charge for the remainder. It was pointed
out that a large part of this current is
sold helow cost (including fixed charges)
and that the small consumer, paying nine
and ten cents per kilowatt-hour, is obliged
to carry the burden of the fixed charges
resulting from this discrimination. In
relief of these conditions the petition
asks that rates be established whereby
all consumers shall contribute fairly and
equitably to the charges and profits of
the business and thai discriminatory
rates be prohibited; in other words, that
a maximum and minimum rate be es-
tablished, the difference between which
shall repesent merely the physical dif-
ference in the cost of producing in small
and large quantities.

The first public hearing in answer to
this petition was held before Commis-
sioner Maltbie on Monday morning.
October 23. Little was done at this meet-
ing save establishing the fact that the
Public Service Commission had jurisdic-
tion in the subject at hand, and in out-
lining the method of procedure. In the
latter connection it was decided that a
definite case should be selected upon
which to base the charges of discrimina-
tion, and thus avoid introducing too many
generalities. In order to afford an op-
portunity for both the complainant and
the respondent to prepare" their cases,
the hearing was adjourned till 2:30 p.m.,
Wednesday, November 1.

The attorney for the New York Edison
Companv admitted the rates as set foi.h
in the petition but denied that they were
discriminatorv or that current is sold for
less than cost.

In commenting upon this attitude it
may be explained that the New York
Edison Company, like most central sta-
tions, contends that inasmuch as it is

obliged to maintain equipment of a cer-
tain capacity to supply its large number
of small consumers, who use power only
part of the time, it can supply a number
of large consumers during certain hours
without extra cost except for the fuel
and water used. Upon this basis it is
contended that current is not being sold
below cost but that a profit is actually
being made. Of course, the fixed charges
are borne by the small consumer.

In contrast to this attitude it will be
recalled that in a recent discussion upon
"Central Station versus the Isolated
Plant," a certain New York Edison repre-
sentative insisted that a high rental rate
be charged to the isolated plant for the
space occupied in the basement of a
building; yet the basement was there
as a necessary adjunct to the rest of the
building.

It seems hard to reconcile these two
diametrically opposite attitudes regarding
questions involving the same principle.

Generally speaking, why should gas
be treated differently from electricity?
They are closely analogous, both in pro-
duction and distribution; yet gas is paid
for at eighty cents a thousand cubic feet
whether the consumer uses one or fifty
thousand cubic feet.

The demands made in the present in-
stance have precedent in the decision of
the Wisconsin Railroad Commission in
the case of the Menominee & Marinette
Light and Traction Company. Here the
commission fixed not only a maximum
rate for light and power, based upon the
hours of ser%'ice, but also a minimum
rate of 4'j cents per kilowatt-hour. In
this connection the following is quoted
from the decision of the cominission:

"To put a rate schedule into effect for
permanent use, which is so low as to
hardly cover the output costs or that
yields so little in the way of revenues as
to leave little or nothing for interest, de-
preciation and taxes, would seem to be
nut of line with sound business practice
and discriminatory against other cus-
tomers,"

Again, in the report of the Public Ser-
vice Commission for the second district
of New York State, is to be found the
statement:

"Until ,Fune, lOlO, the jurisdiction of
this commission over rates enforced by
gas and electric corporations was limited,
so far as concerns express statutory pro-
vision, to investigate and determine upon
complaint the maximum price to be

678

POWER

- October 31, 1911

charged. In that month there became ef-
fective, by an act of the legislature,
amendments to the Public Service Com-
mission law by which the general and
specific powers of the commission were
greatly enlarged.

"That the question of just and equi-
table rates was not to be solved in the
exercise alone of the authority to fix the
maximum price, and that there exist
broader and more fundamental problems
to be dealt with, is now regarded in
these amendments."

Then follow some long extracts from
the amendments which in principle af-
firm the contention that not only a maxi-
mum but also a minimum rate must be
prescribed in the schedule of rates.

Ciraft

We are in frequent receipt of letters
from engineers expressing indignation
against the charges of graft now so often
appearing in the trade press and in en-
gineering assemblies; that they are dis-
honoring a body of men who are of
strictest probity; that such charges are
undoing the uplift for which so many
engineers are earnestly laboring.

These contributions would be unan-
swerable if there were not enough truth
in the charges of graft to make the whole
question too serious to be ignored by any-
body who is interested in the well-being
of the engineer.

There has been no charge that grafting
is universal. There are many engineers
who are unapproachable with bribes and
above the taking of tips. The reproaches
which are being heaped upon the prac-
tice are not for them. Let the galled
jade wince.

The honest engineer may find it hard
to remain silent under an inculpation of
his vocation which he considers may in-
volve him by implication, but if he must
speak let his voice be raised in con-
demnation of the practice, not in con-
demnation of the exposure of it. The
way to get rid of a festering growth is
to cut it open, expose and purge it, not
to cover it up with absorbent cotton and
scented talcum.

We have learned that one letter re-
ceived by an advertiser bursting with
virtuous indignation at the graft charges
published in one of his advertisements
was inspired by a competitor of the ad-
vertiser.

We have seen a salesman go forth like
a. paymaster with his pockets full of
little envelops each with its monthly
"perquisite" for one of his customers.
We have heard salesmen discuss en-
gineers with regard to their degree of
approachability, referring to them as
"straight," "cheap," "comes high," "takes
his," etc.

The practice of grafting is not confined
to the vocation of engineering, but Power

is. It is our concern to criticize and con-
demn anything which militates against
the standing and progress of the power-
plant engineer, and it certainly does put
him in an equivocal and humiliating posi-
tion to accept perquisites, especially in
the shape of money, upon the supplies
which he purchases for his employer.
.Any employer who detects such a prac-
tice would be justified in summarily dis-
missing the engineer, ordering the sales-
man off the premises and tabooing the
further use of his goods if anything else
can be had which will do; and there
usually can, for real and exclusive merit
does not need to buy its way in nor have
to pay to stick.

It is good law in this country that
every man is innocent until he is proved
guilty, but in common, everyday practice
suspicion of wrong often places an honest
man in a position where he is compelled
to prove his innocence.

Conditions are such today that rep-
utable manufacturers and owners are be-
ginning to doubt the honesty of engineers
whose records are clean and above re-
proach.

The honest engineer should disabuse
his employer and the business public
of this opinion, and it can be accom-
plished by every reputable engineer treat-
ing with disdain the salesman who of-
fers graft, refusing to use the products
of manufacturers who authorize it and
making it so hot for the grafting engineer
that he will be compelled to turn honest
and self-respecting if he would continue
in a vocation which as a whole stands for
honesty as well as skill and intelligence.
Expose graft often enough and strongly
enough and it will die of sunstroke.

Suction Pipes for Pumps

When pumps are installed with long
suction pipes the rise or slant of the
pipe from the source of supply to the
pump should be continuous if satisfac-
tory operation is expected. If there is
a vertical rise in the pipe and then, as
is often the case, a descent to the pump,
the elbow or bend at the highest point
and the length of more or less approxi-
mately horizontal pipe forms an air
chamber or pocket which is sure, even
with the use of a foot valve, to cause
much trouble.

If the volume of air trapped in the
pipe is large as compared with the pis-
ton displacement, it may he found im-
possible to start the water because of
the inability to discharge this air through
the pump. There is a great difference
between the air caught in the suction pipe
and that in a purposely designed suc-
tion chamber placed on a riser or tee on
the top of the highest point in the pipe.
The stream of water in the suction pipe,
if long, must not be started or stopped
suddenlv and the suction chamber is a

vessel into which the water may flow
continuously during the period of the re-
versal of the motion of the pump pis-
ton.

All water holds air or other gases in
solution in proportion to the pressure,
and under the reduced pressure in the
suction pipe some of the air escapes and
collects where the pressure is lowest.

It is therefore necessary for the suc-
cessful operation of all pumps having
long suction pipes, that the pump be
placed at the highest point in the length
of the pipe, and that the pipe have a con-
tinual if not uniform rise from the well
end of the pipe to the pump.

There should be an air chamber on
the discharge side of the pump as well
as on the suction side, as a volume of
confined air forms an elastic cushion
against which the intermittent action of
the piston is transformed into a steady
flow. Air chambers, particularly on boiler-
feed pumps, should be so arranged as to
catch all the air coming along with the
water and prevent its traveling onward
into the boiler where it aids corrosion.

The sufferers by the failure of
the Austin dam are determined that
there shall be a searching investi-
gation into the cause of the disaster.
.\ citizens' movement has been organ-
ized, counsel engaged and cooperation
with the authorities undertaken. This is
as it should be. If the failure was an un-
avoidable, unforeseeable accident, those
who are being inculpated for it should be
cleared of responsibility and reproach.
!f the weakness of the dam was evi-
denced in advance and somebody took
chances on it just to keep up dividends,
somebody ought to get the same treat-
ment which the man who runs a boiler
known to be weak until it explodes ought
to — and usuallv does not — get.

Rhode Island coal is being mined in
considerable quantities and sold in the
natural state and briquetted for domestic
use. .A circular recently issued says
that the company is turning out about
150 tons of briquets a day, that all the
steam for the different boilers at the mine
is generated from Rhode Island coal and
that 1012 will see about a thousand tons
of coal a day outside of the briquets
being prepared daily.

Our skepticism regarding the value of
the treatment with a homeopathic dose
of calcium chloride has turned out to
he well founded. The coal has been
found to burn just as well without it.

New York's long immunity from boiler
explosions has finally been broken. An
explosion has just occurred in Manhat-
tan. With the exception of the explosion
in Brooklyn a year ago. Greater New
York has been remarkably free from
disasters of this kind.

October 31, 1911

POWER

679

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.

Evaporation and C.ojuloisation

The condensation returned to the boiler
at 212 degrees is 712.27 pounds per
hour, which gives

■ = J 3. 7 4 boiler hone power

The evaporation is 10 pounds of water
per pound of coal, and 3'j pounds of
coal are burned per boiler horsepower
developed. But

23.74 X 3.5 = 83.09 pounds
of coal required per hour and

-=: 71.J2 pounds

10 '

of coal per hour. Why do these results
not check?

B. H. P.
A boiler horsepower is 30 pounds of
water evaporated from feed water of
100 degrees into steam of 70 pounds
pressure. This is equivalent to
(1179.8 — 67.97) X 30 = 33,355 B.t.u.
the difference between the total heat of
a pound of steam at 70 pounds pres-
sure and the heat already in the pound
of water at 100 degrees multiplied by
30. The values used are those of the
new Marks- Davis tables. If 712.27
pounds of steam are made per hour at,
say. 100 pounds absolute, from the re-
turns at 212 degrees, it will take
(' 1186.^ — 180) -12. 27 _
.■?3..^.=i.S

horscpouii

The 1186.3 is the total heat of steam of
100 pounds pressure, the ISO the amount
of heat in a pound of water at 212 de-
grees. If the pressure were different
there would be some other value than
1186.3 for the total heat and the horse-
power would be different. The statements
that there is an evaporation of 10 pounds
of water per pound of coal and 3.5
pounds of coal are used per boiler horse-
power are interdependent. If a boiler
horsepower is .■?3.,^.S.S B.t.u. and it takes
3..'> pounds of coal to make it, then each
pound of coal must furnish

=: gs ^o BJ.u.

V.5

If these evaporate 10 pounds of water,
each pound of water absorbs P.V3 B.t.u.
If the feed water is at 212. in which
case the heat already in it will be ISO
B.t.u. the total heat of the steam which
is making must be

180 J 953 - 1133 B./.U.
which is true only of steam at less than
6 pounds absolute pressure.

-= 21.49 l>oiter

If steam of 100 pounds absolute pres-
sure is made, having a total heat of
1 186.3 B.t.u. per pound and only 953
B.t.u. are used per pound to do it, the
feed water must have

1 186.3 — 953 = 233.3 B.t.u.
in it, in which case its temperature would
be about 265 degrees. The assumptions,
10 pounds of water per pound of coal,
3.5 pounds of coal per boiler horsepower,
do not agree, except under particular
conditions of steain pressure and feed-
water temperature.

Srze of Ctist-ifon I-heanis
What should be the size of a cast-iron
I-beam 12 feet between supports and
supported at both ends; the beam to
carrv a uniformly distributed load of 10
tons?

W. H. W.
The size of I-beam to be used may
be found from the formula:
hh- 2 hjil _ \Vl
6/1 ~ 8 />

where,

H'— Distributed load in pounds;
/ — Distance between supports in

inches;
p - Allowable tension in pounds per
square inch ;
and b, h, b, and b represent the dimen-
sions shown in the accompanying sketch.
Here h-'i.h= 20. b, - 3.2 and h, — 18.8.

hh* 2b,li» . ,
The expression —, is known

as the section modulus; it is de-
pendent entirely upon the size and shape
nf the beam and its values for various
beams arc given in the handbooks of the
steel companies, such as Cambria and
Carnegie.

Assuminc an allo«ablc tensile stress
of .VMM) pounds per square inch, and
substituting in the foregoing formula

_ . , , JO.flOO X 13 X 12 . „
Scdum moilulw "^ v.— ~ = 120

From the steel companies' handbooks a
20-inch. 70.pnund I-beam is found to
have a section modulus of 122. A 12-

foot beam of 70 pounds to the foot would
weigh 840 pounds. Adding this to the
distributed load and solving again for the
section modulus, we have

20.840 X 1 2 X

Sectii>7i nioJtilus ^

1-^5

8 X 3000

A 20-inch beam with a section modulus
of 122 would be sufficient if the cast iron
of which it is made can be depended
upon and if the assumed tensile strength
and factor of safetv fit the conditions.

:::x^:

Size of 20-inch, 70-pound I-beam

Since the depth of this beam is more
than .'tt of the span, the deflection may
be neglected. Furthermore, the cross-
sectional area of the web is about 10
square inches (it being customary to con-
sider only the web when figuring the
shear). This would mean a maximum
shearing stress of about lO(K) pounds per
square inch. But as 5000 pounds may
be allowed with safety for cast iron in
shear, this stress may be neglected.
Hence the only factor to be considered
is the maximum bending moment, by
which formula the size of beam was
found to be 20 inches.

If steel were employed instead of cast
iron, a lO-inch beam would carry the
load.

The failure of an engineer in a New
England brewery to close a valve caused
the blowing away in a few minutes of
'^25.(K10 worth of ammonia gas. After
the gas had begun to flow it was impos-
sible to get near enough to the valve to
riosc it.

680

POWER

October 3!, 1911

Protectiiii^r the Compressors
Bv H. H. Delbkrt

During the month of September we
had an accident to one of our com-
pressors from the same cause as the one
cited by Mr. Schindler in the August 22
issue. If I had given Mr. Schindler's
suggestion more consideration when I
read it, I would have saved the company
some money. Hereafter articles appear-
ing in Power, especially those pertaining
to accidents and new devices, will re-
ceive more consideration from me, and I
will try to benefit by them.

The photograph clearly shows the pip-
ing on my compressor, with the excep-
tion of the unloading device which is on
the opposite side of the low-pressure
cylinder on the intake pipe E. The long
bend is the discharge connected into the
main line under the floor. The unloader
is also connected to the main line under

x-kO*^'

jf^^^y

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V^ »b8H^^^^^Bh l^^^^^^5^'~'*

Arr.'^ncement of Piping to Compressor

the floor, and it will not act until there
is the required pressure in the main line.
On the day of the accident the second
engineer started this unit. As had been
his habit, he closed the relief valves A
and B before opening the main valve C.
Before he could reopen any of the valves
that part of the high-pressure cylinder
above the cylinder proper was blown
off and pieces of iron thrown all over the
plant. That no one was killed or even
injured was almost a miracle. After put-
ting on a new cylinder, I tapped a hole
at D and to it connected the unloader so
that it would act as soon as the pres-
sure was high enough, regardless of
whether the main valve was open or shut.
This arrangement works very well and I
think it is better than a safety valve.

Our unloaders are balanced with a
weight, and by sliding the weight back

on its lever the unloader will operate at
a low pressure.

I am of the opinion that I am not
the only reader who has neglected to
give articles in Power as much con-
sideration as they deserve, and I hope
that this article will be the means of
causing every one of them to more fully
benefit by the good suggestions and de-
vices shown from time to time, and not
wait for an accident to wake them up
as I have done.

Cooling Hot Liquor

By George H. Handley

An interesting experiment was tried
recently of trying to cool boiling liquor
through circulating from one tank to an-

n From CondenseK'

necessary to cool and at the same time
thoroughly agitate the liquor: .

A small air compressor was belted to |
the main shaft and air was compressed '
into a tank to a pressure of 150 pounds.
From this a pipe led into a large coil,
this coil being placed in a tank from
which water was constantly being drawn
off and replenished for mil! service. The
water in this tank cooled the compressed
air to normal temperature. After the air
left the coil it was led to a small vertical
steam pump and was used for power to
drive the pump. The exhausting air was
naturally expanded and was carried to a
large pipe placed into the bottom of the
boiling tank, this pipe being drilled with
a large number of 1 /'32-inch holes which
liberated the air to the atmosphere
through the liquor. The pump meanwhile
was pumping the liquor from one boiling
tank to another through a system of by-
pass valves and after it cooled sufficiently
the liquor was in turn pumped over to
the main supply tank.

While the installation gave satisfaction
inasmuch that the liquor was cooled off
in about 24 hours, still a later installa-
tion of an ice machine has proved more
economical from a running-cost stand-
point.

CORRESPONDENCE

Opening an Ammonia Joint

In the issue of June 27 my article on
"Opening an Ammonia Joint" was pub-
lished, and in the September 5 issue an
interesting discussion of it by William L.
Keil. I will admit that the article was not
written as clearly as it might have been
and on this account I am sending in

To Charglng-
ConnecfionT "

Fig. 1. E.\P-.\NsiON HE.^DER in Engine Roo.m

other and at the same time discharging
cold air into the bottom of the tanks. The
liquor in question was boiled in tanks
of 1500 gallons capacity. As it usually
took about three days to cool down suffi-
ciently to use and then had to be pumped
from the boiling tanks to the main sup-
ply tank, the following experiment was
tried to cut down if possible the time

additional details which will help to clear
things up.

I have five branch cold-storage plants
to look after and, of course, am ven,-
busy. The engineer who operated the
plant days was a new man, but from his
talk and actions I considered him "well
up" on ammonia and did not question
him when he claimed that he had pumped

October 31. 1911

POWER

681

;• the coil properly. Pumping out was
-ually done with a resel^'e compressor
■ >. 2. I was in the engine room. 50 feet
ay, when I heard the explosion, due
opening the joints, and rushed into
e cooler, w-here I found the conditions

To No. I Compressor

hold of the valve again had got No. 5
instead and closed it. Strange 'that he
should not have noticed the pressure ris-
ing on the gage. I lost possibly 20
pounds of ammonia. The fan which is
used for winter ventilation was started

S m «K

Fic. 2. Suction Header in Engine Room

as previously described. I got the engi-
neer out quickly and later found the
valve on No. 4 coil one-half turn
open and the valve on coil No. 5 had
been closed tightly, although I did
not know it at the time, for in the ex-
citement the helper had opened No. 5
again as he at once realized that the en-
gineer had closed the wrong va've and
wanted to save him if possible. The en-
gineer acknowledged later on that he
might have started to close No. 4, but in
talking had probably taken his hand from
the valve for an instant and in takini;

To Ho. I Compressor

To No. 2

Compressor

and within three hours ever^'thing was
restored to normal. There were three
low-pressure gages and two high-pres-
sure gages in use and no reason existed
for a blunder of this kind, but the human
element must be considered.

Fig. I gives details of the expansion
header in the engine room, Fig. 2 shows
the suction header and Fig. 3 indicates
the change made in the coil in the lower
cooler.

D. L. Faonan.

New York City.

A Case of Frost

Where I am employed we have a four-
ton De La Vergne tandem ice machine.
It was customar>' to carry frost clear
down to the machine and on an average
thirty 300-pound cakes of ice were pulled

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Fic. 3 Change Made in Lower Cooler

in 24 hours. This was all we could pos-
sibly make. This summer, when we
were rushed for ice, the manager sug-
gested that we experiment a little with
the expansion valve. This was done,
and when the frost would get down on
the machine, we would close the valve
a little. The frost would then melt off.
the valves would stick and it would be
half an hour before we could get them
to work normally. The result was a
rise of one degree in the freezing tank.
After that we kept the expansion valve
open enough to get frost on the suction
pipe coming from the freezing tank and
did not allow frost to get on the ma-
chine. When the frost started to melt
from the pipe just outside of the tank
the expansion valve was opened a little
and when we got dr>-, or live, frost the
valve was closed a little. The valves on
the machine never stick any more and
we have increased the capacity of the
machine from thirty 300-pound cakes of
ice in 24 hours to 38. A freezing tem-
perature of 16 degrees is maintained
with the compressor running at 90 revo-
lutions per minute.

.\ndre\i;' Blair, Jr.
Norborne. .Mo.

Porous Brine Pipes

Some time ago a lO-ton absorption ma-
chine of which I had charge was losing
the brine at a ver>' rapid rate without
leaving any sign of where it was going.
The covering of the return pipe, which
was 2-inch wrought iron, was of hair felt
and tarred paper applied in layers until
it took on the appearance of a 4-inch
pipe. The inlet was covered with heavy
cork insulation with all its joints sealed
with asphaliic compound.

The brine in the tank could not be
kept at a uniform level under any cir-
cumstance and it kept us busy adding
calcium chloride and water. To get at
the bottom of the trouble, we removed
the tank and tested it for leaks. Having
satisfied ourselves that the tank was
tight, we uncovered the brine pipes. The
canvas covering on these pipes was
heavily painted and the minutp we stuck
a knife into the canvas we were de-
luged with brine. Having removed all
of the covering, we found the pipe to be
quite porous; it was possible to push a
nail through almost any part of the pipe.
This condition was in all probability
brought about by Ihc alternate freezing
and thawing of the condensation on the
pipe.

All the piping was removed and gal-
vanized pipe and fHiings substituted, with
the result that for H\c months we have
been able to keep the brine nt a constant
level and density. I think that it would
be good practice to use more galvanized
pipe and fltlines in the brine apparatus
and less of the black pipe.

H H Bi'Rirv.

Bronklvn, N. Y.

682

POWER

October 31. 1911

Fatal Flywheel Explosion at Baltimore

On Monday afternoon, October 16, an
accident occurred at the power plant of
the Consolidated Gas. Electric Light and
Power Company, Westport, Md., which
resulted in the death of the engineer and
the scalding of two other men by escap-
ing steam. The fatality was caused by
the fragments of a bursting flywheel
severing two 4-inch pipes which branched
out from a 6-inch auxiliary steam pipe.

The flywheel belonged to a small ver-

1

j 1

1

r^

Fig. 1. Broken Flywheel Shown Back
OF THE Two Centrifugal Pumps

tical steam engine direct-coupled to a
12-inch centrifugal circulating pump
which was located in the basement. This
unit serves the barometric condenser
which was connected to one side of a
5000-kilowatt. twin, angle-compound
main-generating unit. A duplicate cir-
culating unit served the condenser used
with the other side of the main engine.

Both of these au.xiliaries were set in a
concrete compartment, formed on three
sides by the foundation of the main en-
gine, the other side of the compartment
being open to the basement. The engines
were set next to the end wall of the
compartment, with enough space to get
around them, and a passageway was pro-
vided between the two units and between
each unit and the side wall. A view of
the two pumps is shown in Fig. 1.

The large engine was not running at
the time of the disaster, and Engineer
William H. Messick, who was killed, as-
sisted by two others, was at work on the
small engine packing the throttling-gov-
ernor valve stem and making adjust-
ments.

It is not known what Messick was do-
ing just prior to the accident. He was,
however, standing on the guard over the

]]'aste catching in the
gear ivheels of a throttling
governor cansed the engine
to speed lip and lereck its
fly'ivheel.

The fiyivheel of a dupli-
cate engine icns also urecked
and a numln r of steam and
neater pipes leere sei'ered.

An engineer icas scalded
to death hy escaping sttin)i.

bottom part of the channel iron was
drilled and tapped for a V-pointed ad-
justing screw, the pointed ends of which
fitted in the countersunk hole at the
top of the governor stem. This adjust-
ing screw was set so that the governor
could not throttle the steam supply en-
tirely should the governor belt come off,
but would give the engine enough steam
to supply sufficient circulating water to
keep the main engine running under a
vacuum.

flywheel of the engine on which he was
employed, which would bring him at a
convenient working level with the gov-
ernor on which he was probably work-
ing. His assistant was on the floor in
the rear at or near the extension throttle-
valve stem.

It seems that the engine had been
started and was evidently running at full
speed, for after the accident occurred
the throttle valve was found open about
' J inch, and a bunch of waste was tightly
wedged between the governor gears, as
shown in Fig. 2. This waste was doubt-
less the direct cause of the accident. How
it got there is not known, but the chances
are that it was in the hands of Messick
and was accidentally drawn in between
the gears, which prevented the governor
from operating.

The governors on both engines were
Fitted with a safety stop, but a precau-
tionarv arransement to guard asainst a

Jlnch of Waste in the Gov-
ernor Gears

It is not known whether the adjusting
bolt had been changed or whether the
centrifugal pump had lost its water, or
both, but such a combination of events
would, with a clogged governor, have

Fig. 3. FragjMents of the Flywheels, Broken Pipes and Wrecked Governor
of Idle Engine

shutdown had been applied to each. This been sufficient to cause the engine to run

consisted of a piece of iron bent in chan- away.

nel form, the side ends of which were When the flywheel burst it not only

attached to the floor beams above. The severed the two 4-inch steam pipes, but

October 31. I91I

P O W E R

683

fractured a 16-inch condenser discharge
pipe and demolished another of the same
size, besides wrecking the flywheel of
the idle circulating-pump engine and also
smashing the hearings of the idle pump.
Being confined in the concrete chamber.

the rims on both flywheels were broken
into fragments, as shown in Fig. 3.

With the breaking of the two main
steam pipes, the pump compartment was

instantly filled with steam at 175 pounds
pressure. Messick was caught before he

could escape, and when found was lying
between the idle engine and the wall
with a lacerated scalp and was tiadly
scalded.

The main engine escaped injury and
the total monetary loss will be small.

Boiler Explodes under Sidewalk

New York City was the scene of a re-
markable boiler explosion which occurred
at midnight on Friday. October 20. when
one of two return-tubular boilers which

The 3-inch tube pulled out of the front
head first. This head was flanged out
and when the tubes gave way the head

bulged nMtu:ir.1 .Thn\)t (1 inches.

Fig. 1. Rear End of the Boiler and PRO.ihXTiNC Tubes

The 3-inch tubes pulled out of the front
and rear heads, but were not flared or
beaded. As the tubes drew out of the
front head the pressure within the boiler
bulged the rear head some ti inches or
more, and the stays which braced the
rear head above the tubes were fractured
or pulled apart. Several braces at the
front head of the boiler were also broken.

.About a dozen tubes were blown clear
of the boiler, but most of them were
forced partly out through the rear head
by the force of the pressure or by im-
pact as the boiler crashed into and
through obstructions, coming to rest
against the street abutments, as shown in
Fig. 1, and crumpling the end of the rear
course of the boiler shell as if it had
been so much cardboard.

The explosion wrecked the basement
and front of the building immediately
fronting the boiler room and tore up the
sidewalk for a distance of about l.'^O feet,
throwing the heavy flagstones, weighing
hundreds of pounds, out of place and
leaving the basement filled with debris,
as shown in Fig. 3. The second boiler,
which fronted the exploded one. was not
moved from its setting, but the brickwork
is considerably damaged and the side-
walk above it has caved in, practically
ruining the setting.

The exploded boiler in its flight under
the sidewalk passed through a 3-foot

were located under the sidewalk ex-
ploded. These boilers supplied steam
for the ammonia compressors of the
Greenwich Coal .Storage Company, 402
Greenwich street.

The exploded boiler was built in 1888.
and was 15 feet long and 60 inches in
diameter. The shell was made of '.s-
inch steel; the heads were ' _■ inch thick
and contained eighty-two 3-inch tubes.
The boiler was tested June <>, I9ll, at
120 pounds hydrostatic pressure and the
allowable working steam pressure was
80 pounds per square inch. The boiler
was equipped with a ball and lever safely
valve.

Such examination of the shell as is
possible in its present position and sur-
roundings, shown in Fig. 1, does not
revejl that the sheet has been distorted
by excessive pressure, and, so far as can
be seen, the shell is intact with the ex-
ception of being crumpled at one end
and bent along its side, due to striking
obstructions in its flight of approximately
\hO feet under the sidewalk.

Fig. 2. Wrecked Boiler Room i/nder the Sidewalk
THE Boiler Demolished

AND Brick Wall Which

684

POWER

October 31. 1911

brick partition wall and also wrecked the
water and gas inains. The broken water
main flooded the basetnent and the es-
caping gas caught fire, which was soon
extinguished. One piece of the flagstone
severed a girder of the elevated structure
above, when it was blown from the side-
walk. The ammonia pipes in the cold-
storage plants were broken and the
fumes made the work of searching for
the injured difficult.

Twelve persons were more or less in-
jured, the most seriously being a police-
man who was standing on the street cor-
ner. One leg was broken by a flying
tube and he was badly bruised.

A representative of the company stated
that the engineer, who did his own firing,
was in the engine room with several
other workmen when the accident oc-
curred. None was seriously injured.

This is one of the most remarkable

luminating and miscellaneous oils and
greases in use, of which ten are lubri-
cating, two illuminating, four miscellane-
ous oils; and five are greases.

All lubricants and oil are standardized
as follows: valve, air-compressor, cyl-
inder, marine, stationary, locomotive,
turbine and gas-engine oils; crank-case,
car, transformer, lard, ammonia, cylinder
and crude oil. Greases: nonliquid oil,
cup, gear, cable and crank pin. Illuminat-
ing: signal and kerosene oils; gasolene.

Of these oils, 12 are received by the
commission in 50-gallon steel drums, and
three in cases of two 5-gallon cans each.
Three kinds of greases are received in
barrels and two in 25-pound cans. Crude
oil is supplied to the different points in
containers convenient for the work re-
quired, drawn from the crude-oil tanks
located on the isthmus.

The approximate monthly consumption

Fic. 3. What Is Left of the Sidewalk. The Boiler Is Shown at the Extre.me End

boiler explosions which has ever occurred
in the city of New York, and it is most
fortunate that it happened when the
streets were practically deserted. More
details as to the direct cause of the ex-
plosion may be brought out at the trial
of the engineer, who has been arrested
charged with criminal neglect.

Lubricants Used in Canal

Equipment

By Don E. Erwin

The extensive canal, floating and plant
equipment necessary to carry on the con-
struction of the Isthmian canal has com-
pelled serious study of the lubricating
conditions by the canal engineers.

.As defining in a general way these
conditions, the following description of
the kinds of lubrication, the manner of
receiving it and its distribution and use
will be of interest:

There are 21 kinds of lubricating, il-

and use of each grade by the commission
and the Panama railroad follow: valve
oil, 5350 gallons; for internal lubrica-
tion of all steam valves and cylinders.
Air-compressor cylinder oil, 150 gallons;
for internal lubrication of air cylinders
of all compressors, pneumatic hammers
and drills. Alarine-engine oil, 4175 gal-
lons; for marine engines and block bear-
ings of suction dredges. Stationary-en-
gine oil, 2750 gallons; for general lubri-
cation of stationary engines and machin-
ery, electric motors and dynamos. Loco-
motive-engfne oil, 3850 gallons; for all
locomotives, running gears of locomo-
tive cranes, deck machinery of dredges
and for cold saws in machine shops.
Turbine-engine oil, 400 gallons; for the
step bearings of turbine engines in elec-
tric plants. Gas-engine oil. 150 gallons;
for the cylinders of internal-combustion
engines. Crank-case oil, 100 gallons;
for crank cases of Westinghouse vertical
compound engines. Car oil, 5175 gal-

lons; by the electrical division for the
generally, steam-shovel bearings, tripod
drills, etc. Transformer oil, 200 gal-
lons; by the electrical divisions for the
oil-cooled transformers. Lard oil. 50
gallons; various uses. .Ammonia cylinder
oil, 50 gallons; for internal lubrication
of ammonia compressor cylinders. Crude
oil, 1000 gallons; for steam-shovel chains
and special designated uses. Kerosene
oil, 10,000 gallons; for illuminating and
cleaning purposes. Signal oil, 100 gal-
lons; in railroad lanterns and cab lamps
of engines.

Gasolene, 3350 gallons; for motor
cars, launches, blow torches, cleaning,
etc. Nonliquid oil, 1850 pounds; used
on Gatun cableways and air cylinders.
Cup grease, 6000 pounds; for use in
compression cups. Gear grease. 6175
pounds; on gears, center and side bear-
ings, etc. Cable grease, 1000 pounds;
used on Gatun cableways. Crank-pin
grease, 40 pounds; on locomotive crank
pins where equipped for its use.

Method of Handling

All lubricants and oils are received at
the general storehouse located at Mount
Hope, and from there are distributed to
the division storehouses, including the
Panama railroad and the 10 outlying de-
pots, from which points they are sup-
plied to the local oil houses, situated
at places convenient to the work, whence
they are issued in daily, weekly or month-
ly quantities, as requisitioned on oil
tickets, by employees in charge of the
equipment or plant. Oils are delivered
to the local oil houses in 50-gallon drums,
which are used as containers by the in-
sertion of a faucet, and have a value to
the commission when returned to the
contractor in good order.

.All equipment and plants of the com-
mission and the Panama railroad are
placed on a monthly allowance, accord-
ing to the necessities and nature of the
work performed. A monthly report is re-
quired of the consumption of each indivd-
ual piece of equipment and plant, which
shows service days, and a satisfactor>' ex-
planation of amounts used in excess of
the monthly allowance must be made.

Monthly reports are posted at different
places for the information of all con-
cerned. All equipment and plants are
furnished with standard oiling equipment
and are kept in good repair, and are sup-
plied also with containers for oil drawn
for future use.

Oiling systems and drip pans are in-
stalled where required, and where suffi-
cient quantities of oil can be reclaimed,
filters are furnished. When the reclaim-
ing of oils through drip pans is not suffi-
cient to warrant the installation of a
filter, oil is filtered at a central station
for re-use. Careful attention is given to
every detail of the work in regard to the
issuing, handling and consumption of
lubricants and oils, and instructions have
been issued with reference to economy.

October 31, 1911

POWER

Double Piston Unidirectional
Flow Engine

One of the principal advantages of the
direct-flow steam engine of Professor
Stumpf is that the variations of tempera-
ture of the metallic cylinder walls with
which the steam finds itself in contact
during expansion are reduced to a mini-
mum and consequently the exchanges
of heat between the steam and these
walls, the losses of heat and the internal
condensation. It will be noticed that in
the single-piston engine designed by Pro-
fessor Stumpf there are two surfaces
by which considerable heat may be dis-
persed. These are the two cylinder heads.

In the model constructed by Kuhnle,
Kopp & Kausch, of Frankenthal i Pala-
tinsk), this is avoided. A partition with
a stuffing box through which the common
rod carrying two pistons passes divides
the cylinder into two equal parts. The
steam-inlet valves are arranged near the

ing boxes are improved since they have
to resist only low temperatures and pres-
sures..

Automatic Cu.shioned Angle

and Globe Valve

The automatic cushioned angle and
globe valves shown in the accompanying
illustration are lined with a bronze bush-
ing A made in one casting down to and
including the seat. The piston or valve

______ 111*— - ^'liJO-

J fp

Unidirectional Flovc Engine

B is of bronze and is fitted with a rubber,
leather or lead disk, according to the
service required.

The water coning under the piston or
valve B also enters through port C on top
of the valve owing to the greater area
above the valve B for building up the
head pressure according to the size of
the valve.

A pilot valve with a copper float at-
tached is fitted to the top, or this pilot
valve can be detached and placed at any
distance desired. When the water in the
tank reaches the required hight, the cop-
per float allows the pilot valve to close,
and the pressure builds up above the pis-
ton B, forcing it to close and shut off the
flow of water through the valve. Water
withdrawn from the tank or heater per-
mits the float to drop, which opens the
pilot valve, and allows the pressure above
the piston to escape just enough to per-
mit the flow of water to restore the re-
quired level in the tank.

These valves permit a small inflow of
water or a large inflow of the full capa-
city of the pipe, according to the amount
of water withdrawn from the tank. They
are manufactured by the Golden-Ander-
son Valve Specialty Company, Fulton
building, Pittsburg, Penn.

Triple Sbeet Packing

A new sheet packing has recently been
gotten out by the Gutta Percha and Rub-
ber Manufacturing Company, 12(3 Uuane
street. New York City, It is made up of
three sheets comprising a hard black-rub-
ber sheet between two sheets of red-rub-
ber compound. It is designed with the
idea of producing a strong, tough pack-
ing which will be tight and remain

middle of the cylinders as shown at B,
The exhaust escapes through the open-
ings at D, which are uncovered at the end
of the stroke.

As will be readily seen in this model,
the loss resulting from the contact of the
steam with the cylinder heads is much
reduced. As to the outer ends, an auxil-
iary exhaust port keeps them constantly
in contact with steam of the condenser
pressure, with the result that the differ-
ence between their temperature and that
of the surrounding air is relatively small.
The disadvantages of the system would
appear to be a more complicated con-
struction than that of the Stumpf, and
the difficulty of access of the stuffing box
in the central partition. On the other
hand, the conditions of the exterior stuff-

""""t^^^ll

Srctions of Cushioned Ancle and Globe Valve

686

POWER

October 31. 1911

permanent in the joints no matter how
rough the surface of the flanges may be.
It is said that it is not affected by expan-
sion and contraction of the piping, and
that it will not crawl but will remain in
place after being inserted between the
joints. It is suitable for use with steam,
hot or cold water, air, gas, ammonia and
for other uses.

Cooky X'alve Rotor

This little device, illustrated herewith,
has been designed to fit over a pump
valve tight enough to slightly rotate it
when water is discharged through the
valve seat.

This rotating cap is fitted with wings
which are cast slantwise to the outside
edge of the cap. When the pump plunger

'^llt

Coolly \al\e RfnoR

discharges water it strikes the projections
and the valve is turned slightly. This
rotating motion is supposed to keep the
face of the valve true and prevent leak-
age.

The device is manufactured by Cooley
& Milligan, 320 Ford building, Detroit.
Mich.

A Large Pumping Outfit for
Mine Drainage

The El Oro (Mex.) Mining and Rail-
way Company has just installed one of
the largest motor-driven pump equip-
ments ever built for unwatering a mine.
The pump, which was built by the Goulds
Manufacturing Company. Seneca Falls.
N. Y., has cylinders 6x20 inches and a
capacity of 500 gallons per minute. The
construction is such that the pump can
be readily dismantled and lowered down
an ordinary mine shaft and when as-
sembled it requires very little head room.
The motor to drive the pump is a 200-
horsepower three-phase machine of West-
inghouse make. It drives the pump
through double-reduction gearing, giving
the crank shaft of the pump a speed of
35 revolutions per minute. The equip-
ment is installed in the bottom of the

mine and pumps against a head »f 1300
feet.

This installation affords an excellent
illustration of the advantages of the elec-
trically driven pump in mine service. The
flexibUity of the equipment permits it to
be installed and operated in almost any
location.

Fatal Boiler Accident on
Torpedo Boat

On October 23, a water tender was
killed and a fireman badly scalded when
two boiler tubes blew out on the United
States torpedo boat "Tingey," off Charles-
ton, S. C. The accident is the second
of the sort within a period of four days,
the "Wilke's" boiler tubes being blown
out on October H'.

NEW PUBLICATIONS

Bulletin 49 of the engineering-experi-
ment station of the University of Illinois,
"Tests of Nickel-steel Riveted Joints,"
by A. N. Talbot and H. F. Aloore, de-
scribes tests of riveted joints of nickel
steel in tension and in alternated tension
and compression. The slip of rivets and
the strength of joints were determined.
From the tests, the general conclusion
is drawn that in riveted joints, designed
on the basis of ultimate strength, the use
of nickel steel may be of advantage; but
that in riveted joints designed on the
basis of frictional hold of rivets, while
it may be advantageous to use nickel
steel for the plates, rivets of ordinary
steel seem to resist slip as well as rivets
of nickel steel. Free copies of this bul-
letin may be had by writing to W. F. M.
Goss. University of Illinois, Urbana. 111.

SOCIETY NOTE

The educational committee of the In-
stitute of Operating Engineers is at work
on the lesson papers to be used in the
various years' studies by those who in-
tend to follow the courses of the Institute.
These courses have recently been adopted
in Armour and Lewis Institutes, of Chi-
cago, and the Y. M. C. A's. of New York
City, Buffalo and Denver. The educa-
tional bulletin, giving the facilities for
securing the courses in the several cities,
io ready and may be secured by applica-
tion to the secretary of the Institute,
Hubert E. Collins. Engineering Societies
building. West Thirtx-ninth street, New-
York City.

OBITUARY

\x the instant of going to press we
learn of the death of Robert Mather,
chairman of the board of directors of
the Westinghouse Electric and .Manufac-
turing Company.

How Fireman Cirimaldi Lost
His Job

By H. E. Hopkins

I "at luck \\;it I lu'v' makf-a iiif- seek!
it jump' ui)on iiic moocb-a too queek.
.lus" wpn I sen* for da famb' to come —
\\\ buy nio da home in da Hail Columb',
I'or Rosic. an' .loe, Giovanni, an' Mick —
I 'a l)CeK-a boss say: "Get out, d quick:

I'iptro .Micliaelo (irimaldi's my nam',

.\n wpn to da Ian' of da free I cam'

I l)iiy da hanan' an push-a da cart

An* makf-a moocli .soldi riglit from da siari.

lUit dat is no kin' of a l>eeziness —

I work da.v an' niglit an' get-a no res*.

So a fren' of mine from da ol' countree
Say lie know a job dafll jus' suit me:
■■|)e.v want a sood man at da power-house:
Ilright, steady man — no wat you call •sous.-.*
Wide in de should', an' strong in da muse',
one of dose wops dat is mooch-a da husk'."

Me tak' me rouu' to da engineer

\n say to heem : "I'ietro is here. "

I lat Imss say : "Alright !" — iike-a dis —

■ Von jus' da man for dis Ijeeziness.

1 need a feller wat I can trust

I'o keep dese boilers from makin' da bust.

^ ou 'tend to your work de bes' wat you know

.\n' you'll get tine wage" — wat you call dough.

.\ll da day long da fires me stoke

\-a dcig-a da clink' wid da long poke'.

I hoe out da ash' into da pile —

It make-a da heap one, two, t'ree mile!

I shov' da coal 'till I'm red in my face ;
Make-a me feel — Wat you call dat Imt

place 'i
I watch-a da gage an' da indicat' —
'Sapristi I " dat boss say : "You is firs' rate : "
"i'was den I was feelin' beeg by da chest.
I could sen' for my Rose, Mike an' da resi !

So I shov' an* poke. As da clink' I loose
I seeng out my t'roat jus' Iike-a Cams'.
But — one day dis countryman fren' of mine
Makes in a letter dis mooch-a bad line :
"I got .vou dis job; now, you'll hev* to pay
( me 'undred soldi by nex' Thursday I"

He tink I mus' be Giovan' Rockfellar.

Wid mooch-a da mon' heap' up in da cellar :

■Sapristi !" I say. "You try to do me?
-No ; dis is da countree wat is call' free.

lake it some straight from Meester (Jrimaldi ;

lis Uosic's bambinos gets da soldi \"

I feex it for jou.: I make-a vcndctf,"
Say 'I'oni to me : "I get-a you yet !"
He swell heemself up jus' lik' a iMiler
Till heem look mooch as a lobster broiler.
**1 get da revenge:" cry Toni to me,
.\n' T tell heem go chase: bully da gee!

I was hoping some day to get da lie',
.Kxi hev' in mv home evcryt'ing nice.
An' giv" da bambinos mooch educat' —
But liecaus' dis Toni did me so hate.
Heem sneak in da fire room — lay me out flat
Wid da beeg blow jus' back of my hat I

Hen I know not'lng for six-a week quite
Kor my head did dijes' too mooch daylight.
.\n' wen I go back to dat lirin' shop
l>M boss heem had hired anoder strong wop.
Heem tell me lik' dis: "Too mooch-a fight.
No good for da fire. Out of my sight !"

.\n' dis is da why dat luck mak' me sick !
P'raps I go get-a da shov' an' da pick :
Mebhe 1 'list in da White-a da Wing.
1 mus' mak' a liv" liy doing somet'ing —
Sapristi! I'll t>e one ijran' poleetirian :
-Mak' plenia mon' — don" need da poscetion !

Ul

\o\. .44

NKW YORK, NOVK.MHER 7, 1911

19

A representative of a contracting firm
was inspecting some repair work in
one of the large school buildings of
about 6o class rooms in a large Eastern
city when the temperature outside was about
15 degrees above zero.

The attendant was complaining that he had
to start the heating apparatus in order to have
the building comfortable, Monday morning.

The representative, hi great surprise, asked
the janitor if he was not in the habit of
operating Ihe heating system in this kind
of weather continuously, even wlicn Iherc
were no sessions? "Oh, no," he re])licd.
"except for banked fires, it is only in such
weather as this that we run for several
hours before school opens and, of course, dur-
ing school sessions."

Imagine a commercial building of this
size with the heating system practically
inoperative lor such a long jjcriod and esti-
mate the extra boiler power recpiired to
supply sufficient steam in a few hours to
replace the lieat radiated through the iloors
and walls. This explains why there were
three 54-inch boilers in the building, all o])c-
rating on a gravity-return heating system
with slow fires and a steam ]>ressure of from
o to .5 pounrls.

There seems to be a great aversion to
designing heating systems for school build
ings that require any skill to o]Krate, not
withstanding the fact that the horizontal
tubular boiler is built ])recisely the same,
whether to be operated at ,s pounds ])res
sure or ifX), and the fuel to be handled will
be greater in proportion for the low presstin-
arrangement.

It would be a large commercial building
that would require boiler cajiacity tf» the

above extent for the ])ower and heating
combined.

Why should large school buildings be
equipped with a])])aratus of the house-heat-
ing tyjjc and operated in the same manner,
any more than horizontal tubular boilers
should be used in large ])ublic-servicc power
stations?

Why not operate and equip large schools
with the same ]ilant arrangement as for
large buildings of other types, burning the
lo\ver-])riced grades of coal, and operate
tlie boilers at their full capacity under
higher j^ressure. with efiicient attendants on
duty at all times?

The enormous fresh-air supply recpiired
onlv during sessions is an added reason
why this method would prove more economi-
cal. The higher boiler pressure enables the
same boiler to carry loacls of wider variation.

In the school i)reviously referred to, large-
size anthracite coal such as is used in the
family furnace at 56 per ton is bunied,
aufl about twice as much boiler capacity is in-
stalled as would be needed at higher ])ressures.
The city pays for the extra boilers and at-
tendant repairs as well as the coal wasted
in handling and forcing the extra fires.

The janitor, who is a licensed engineer,
receives in some cases a lumj) sum for the
labor; the dav fireman is a cleaner most of
llie time and the night fireman is dispensed
with altogether, at a saving of about the
cost of one-lhird Ion of coal jx-r day.

The article on other jiages in this issue
shows how a school may be arranged at a
lower first cost to o])erate with the same
economy as a commercial building with the
exi)enditure of a very few dollars for efli-
cienl help in the fire room.

P O \V E R

November 7, 1911

A Modern Mine Power Plant

Witherbee, Sherman & Co., operating
magnetite mines at Mineville, N. Y., are
equipped to produce over 1,000,000 ton;-
of high-grade ore annually. A small
percentage of the output is shipped with-
out milling, averaging about 60 per cent.
iron and 1.3 per cent, phosphorus, while
a greater proportion of the ore hoisted
is concentrated electromagnetically, the
iron content being raised to 65 per cent,
and the phosphorus reduced to 0.75 per
cent. Special high-grade concentrates
can, if required, be milled to 71 per cent,
iron and 0.17 per cent, phosphorus.

To operate economically the several
mines, each so located that individual
hoists, compressors and concentratinr.
plants are necessary, it was deemed ex-
pedient to install new power plants
and electrify the entire surface and un-
derground equipment. With entire elec-
trification in view, the company has built
a two-unit turbo-generator plant, 800 and
1500 kilowatts respectively, at Port
Henry, N. Y., six miles from the mines,
and has further installed at a Corliss en-
gine, 750-kilowatt generator plant at
Alineville, a 750-kilowatt, low-pressure
turbo-generator set. Two hydroelectric
plants at Wadhams Mills and Kingdom
can be counted upon during a greater
part of the year for a 675-kiIowatt com-
bined load.

The Port Henry plant embodies the
latest practice in a strictly steam-tur-
bine plant operating condensing and
using superheated steam. The power
equipment is noteworthy because of its
magnitude and its thoroughly modern
design. The electrical installation at all
plants was furnished by the General
Electric Company, and was under the
direction of H. Comstock, assistant gen-
eral manager, and H. F. Pigg, electrical
engineer.

The building, roughly T-shaped, of
concrete and steel construction, was de-
signed by H. C. Pelton, of New York.
The floor space, 7500 square feet, in-
cludes 530 square feet of mezzanine
floors. Two-thirds of the area is oc-
cupied by the boilers and the remainder
by turbines and auxiliaries. The walls
are 49 feet high to the coping, and are
windowed to give a generous supply of
natural light. The cubtc contents of the
building are 373,173 cubic feet, and it
"■as erected at a cost of approximately
587,500, or 23''j cents per cubic foot.

Handling of Coal

No. 2 buckwheat anthracite coal is
used as fuel, of which 11 tons, with
proper draft and fired on suitable grates,
will equal the steaming value of 10 tons
of bituminous. The total cost of a ton
of this fuel delivered to the plant is
S2.65 (which includes 15 cents per ton

By Guy C. Stoltz -

and Samuel Shapiro

The new power plant of
]] itiierbcc, Sherman c"
Co., located at Port Henry,
\. y., is equipped with
18O4 horsepower of water-
tube boilers provided with
superheaters, turbine blow-
ers and damper regulators.
The »iaiii units are four-
stage Curtis turbo-genera-
tors.

•Chii'f .-n;;!!!.-,-!. Witlipl'li.-i-. Sh.iniall A: r.,..
-Mineville. X. V.

vMiniilir eii-ineer. Wiilieiljee. Sh'iman .V
Co., Mineville, .\. Y.

for unloading) while the cost for
bituminous is $3.92 per ton. The coal
gondolas from the Delaware & Hudson
main line are pushed up an eighth-mile
spur and dumped between the concrete
bents of a trestle 100 feet long, on the
north side of the building and 25 feet
distant from the front of the boilers.

Fig. 1. Port Henry, N. Y., Power Plant

At present no mechanical fuel-handling
system has been installed; several meth-
ods, however, are being considered. .All
coal is now bein^ handled in wheelbar-
rows of 400 pounds capacity, which pass
over scales to the boilers. Weighing is
necessary in order to determine the daily
fuel cost per kilowatt-hour so that an
intelligent charge may be made at the
station for power distributed from this
plant.

The Stack

Natural and forced draft are required.
The former is obtained by a circular, re-
inforced, monolithic, concrete stack. The
stack is situated centrally between the
line of boiler sets, stands 175 feet high,
a.nd has an internal diameter of 8 feet. A
4-inch air space is provided in the lower
;7 feet of the stack, the outside wall
being 7 inches thick and reinforced
longitudinally with 1 '4x1 '4x i';.-inch T-
bars; the inside wall is 4 inches thick
and is provided with the same reinforce-
ment, 16 lengths in all being used, while
the horizontal j-i-inch round iron bars
are spaced on 18-inch centers. The out-
side shell is reinforced with 80 vertical
bars, the number diminishing to 32 in
the interval of 65 to 85 feet above the
surface. The upper 90 feet, which is a
single shell 5 inches thick, has 16 ver-
tical bars, together with the V^-inch iron
bars on 18-inch centers, equivalent to a
reinforcement of 0.46 per cent. Around
the 3x8-foot breeching entrance to a
hight of 12 feet the stack is lined with
firebrick.

Boiler Roo.m

The boiler room, occupying by far the
greater part of the building, is 105 feet
long by 48 feet wide by 49 feet high. The
floor is of concrete and slopes from the
side walls to the pipe trenches.

The equipment consists of six sets of
Babcock & Wilcox water-tube boilers
with a combined capacity of 1864 horse-
power. Four sets of boilers are rated at
266 horsepower each and the other two
sets at 400 horsepower each, all being
equipped with superheaters. The floor
space occupied by this installation is
1745 square feet, or 35 per cent, of the
total boiler-room area. All the boilers
are provided with No. 3 McClave grates,
having :?j-inch mesh openings. The grates
are especially adapted to bum the small-
er sizes of anthracite, and are so made
that each row of grate bars is divided in-
to a front and rear series by means of
two separate connecting bars, operated
by twin stub levers and connecting rods,
with an operating handle adapted to grasp
either one or both of the levers in such a
manner that the front and rear series
may be operated separately or together.
In the shaking movement of the grates
there is no increase in the size of open-
ings. The grates have an area of 65
square feet, and a slope of '_• inch per
foot.

Blowers

Each boiler is equipped with Wing
turbine blowers to provide forced draft.
The 400-horsepower boilers are provided
with t"'o 20-inch blowers, while each of
the 266-horsepower boilers has a 20-

November

1911

P O W C R

689

inch blower. With the aid of the blow-
ers, 25 per cent, increase in boiler capa-
city is obfeined while using any fair
grade of fuel. Being operated by a bal-
anced valve, through a damper regulator,
the blower is in operation only on a fall
of steam pressure, thus keeping the pres-
sure constant within a few pounds. The
blower is installed in the side wall of the
boiler, and thus requires no floor space
or attention aside from oiling.

\ Davis damper regulator is used in
connection with the Wing blowers. All

working conditio.is, the two smaller
pumps are sufficient, the larger pump
being held in reserve. The water comes
from the condensers in the turbine room
to a large tank 20 feet diameter and
IS feet high, open at the top, which
serves as a storage tank and allows an
escape of the air which comes with the
condensed water. The tank is located
directly in front of the stack in the boiler
room and is supported on steel legs rest-
ing on a reinforced-concrete platform
10' J feet above the boiler-room floor.

Piping
Superheated steam from each of the
boilers is taken through a 7-inch, extra-
heavy pipe, inverted U-shaped, with 12-
foot spread, and delivered to a 10-inch
extra-heavy collecting header placed in
the rear of the boilers and extending the
entire length of the room. From this
main header, two 7-inch, extra-heavy in-
verted-U pipes take the superheated
steam to the turbine. This header is
equipped with five 10-inch, extra-heavy
bypass gate valves so placed that the

Fir.. 2. Layoit of the Witherbee-Sherman Power Plant

the blowers and main dampers of the
smoke breeching are connected to this
automatic regulator, which is guaranteed
to maintain a pressure within 2 pounds
of a flxed amount, 160 pounds in this
case.

Pr.MPs

Two main pumps. 10 and fi by 10-inch
Knowles, and one large Knnwics 16 and
5 by 12-inch compound, duplex, pot-valve
pump are used to supply the necessary
water to the boilers. Under ordinary

The water from this tank is divided to
flow to two Cochrane lOOO-horsepower
feed-water heaters, each having a .S-inch
suction outlet, a 10-inch exhaust outlet,
a 10-inch exhaust inlet and a 3', -inch
waste pipe, which also rests on the plat-
form. The Cochrane healers receive ex-
haust steam from all the auxiliary pumps
to heat the feed water. The remainder
of the feed water is supplied by two
small Knowles pumps. All pumps are
tied into the same supply system and a
4-inch pipe line is used for boiler feed.

steam may be taken froni any set of
boilers or all, according to the need of
the plant. Running parallel with the main
superhcalcd-sleam header is a 2' -inch
auxiliary saturated steam header, from
which proper leads are taken to the
auxiliaries. Extra-heavy piping and fil-
lings are used on all the superheated
lines, and heavy piping and fillings on
all other steam lines. The superhcated-
sleam pipes are covered with H.S per cent.
n;agncsia blocks 1 inch thick and ^ inches
wide, and with double sMndard thickness

690

POWER

November 7. 1911

sectional covering; the outer layer is of
asbestos sponge felt, and the total thick-
ness of the covering is 3'j inches. The
covering for the other steam pipes is
sectional asbestos fire felt of standard
thickness.

S.MOKE

The 4x9-foot smoke breeching is made
up of No. 10 gage iron plate laid on a
framework of 2x2.\l "i-inch angles.
Ii is supported by iron brackets from
the partition wall and is furnished with
two main dampers, one on each side of
the stack and near the stack openings.
These dampers are so hung on ball bear-
ings that there is the smallest amount of
friction, and they are free to open and
close when worked by the Davis regu-
lator, to which, by means of suitable
cords and pulleys, the damper arms are
attached. Besides these two main damp-
ers, each boiler is provided with hand-
operated dampers placed at the boiler-
flue openings and breeching connections.

At present, ashes are handled with
wheelbarrows and before dumping they
are weighed. A McClave-Brooks ash-
conveyer system is to be installed, and
this, with the proposed coal-handling
system, will make the boiler room upto-
date in every respect.

Turbines and Au.xiliaries
The turbine room, 38x52 feet, con-
tains two Curtis four-stage turbo-gen-
erators, one of 800 kilowatts, 6600 volts,
running at 1500 revolutions per minute
and a second of 150 kilowatts and the
same speed and voltage. Both run on oil-
step bearings and are controlled by
hydraulically operated governors. The
turbines are placed on solid blocks of
concrete standing 7 and 9 feet respective-
ly, above the main-floor level. Stairs
lead to an iron-grate walkway which sur-
rounds both turbines and extends to the
north partition wall where are situated
the oil pumps, separators and other
auxiliaries. A full-load water rate of 18
pounds per kilowatt-hour is guaranteed
on the larger unit and a rate of 18.2
pounds is given for the smaller turbine,
lunning condensing. Steam at 160 pounds
pressure and superheated 100 degrees
is delivered to the turbines, while all of
the auxiliaries operate on saturated
steam.

Excitation for the turbo-generators is
furnished by a 35-kilowatt induction
motor-generator set, and by a 25-kilo-
watt horizontal single-stage turbo-gen-
erator; either set has ample capacity to
supply excitation for both generators.

The condensing apparatus for the tur-
bines is of the surface type, and con-
sists of two circulating pumps and two
air pumps supplied by the Wheeler Con-
denser Engineering Company. A vac-
uum of 28 inches is maintained. The
centrifugal circulating pumps are direct
connected to vertical high-speed engines.
The air pumps are of the Edwards ver-

tical type, 8 and 20 by 12 inches, and
deliver the condensed steam to a stand-
pipe and finally to Cochrane heaters of
the open type.

The oil from the step bearings runs
to a collecting tank of 100 gallons capa-
city, from which it is delivered by a
Knowles pump to a Niles filter of 600
gallons capacity, where oil and water
separation is effected. If necessary, the
oil can be heated to lessen its density
before filtering. The filtered oil is then
delivered to one of two step pumps; both
are Dean, 4 and ZVz by 6-inch, outside-
packed plunger type, and operate at 350
and 425 pounds pressure respectively.
The oil from the tank is delivered to an
overhead reservoir at 130 pounds pres-
sure by two Blake 3x4-inch duplex oil
pumps, piston type. From the receiver
the oil flows to the hydraulic governor
and to the top and middle bearings of
the main turbines through bafflers.

The larger turbine is cooled by forced

being covered with' removable cast-iron
plates. One 30-ton Brownhoist crane
is installed in the turbine room. The
entire equipment in this room can be
operated by one engineer and one oiler
for each shift. The entire cost of equip-
ment at the plant was approximately
SI 60,000 installed.

Power Transaiission

Three-phase current at 6600 volts is
sent from the plant over a double trans-
mission line, two sets of three wires each
No. 000 and No. 00 Brown & Sharpe
gage. The lines are strung on wooden
poles fitted with standard crossarms. pro-
vided with locust pins and porcelain in-
sulators. All highway crossings are pro-
tected by safety aprons strung from pole
to pole. Leaving the main building, the
transmission lines run through a small
building of monolithic concrete which
contains lightning arresters of the shunted
multigap type.

Fic. 3. Turbines at the Witherbee-Sherman Plant

ventilation effected by a disk fan which
is mounted on the main shaft. The
stator and rotor on the smaller unit are
cooled by a fan circulation piped to the
generator.

A 20-kiIowatt horizontal single-stage
turbo-generator set provides for lighting
the building and yards. A mezzanine
floor 9 feet above the main floor is built
against the south wall of the room to re-
ceive the switchboard. One of the switch-
board panels is for the exxiter, one for
the regulator, two for the generators and
two for the lines. The cells for oil
switches, transformers for motor-gen-
erator sets, exciters and all high-potential
wiring are located under the switch-
board floor. All piping, where possible,
is distributed to the units through con-
crete trenches in the floor, the trenches

Transforming Station
At Mineville, before entering the trans-
former station, the high-potential lines
run through the A & B distribution sta-
tion, in which is installed a second set
of arresters of the multigap type. Be-
yond the arresters and disconnecting
knife switches the lines are carried
through automatic overload switches and
then to the main transformer station.

The station, of red brick and mono-
lithic concrete, is 20x20 feet. It con-
tains three 500-kiIowatt. 6600-3300 air-
cooled transformers, of the same type;
also four Sturtevant fans directly driven
by 2-horsepower, 110-volt induction
motors for supplying the cooling air.
From this station the lines are taken to
the main distribution station located in
the .\ & B hoist and compressor house.

1911

POWER

691

Pulleys for High Speed Belts

It is well known among those who
have had experience in operating belts
that when the belt speed is high, difficulty
is encountered in maintaining the proper
speed ratio between the driving and
driven pulleys. The speed of the driven
pulley falls below what it should be ac-
cording to the figures obtained from the
formula commonly used for figuring pul-
ley speeds.

As the correct operation of any ma-
chine is dependent upon its running up
to speed, this lagging of the driven pulley
behind its figured speed causes consider-
cble annoyance, to say nothing of loss in
machine efficiency. It is particularly ob-
jectionable because there seems to be no
rule by which just the proper allowance
for lagging can be made, thus bringing
the machine to the right speed, notwith-
standing the slippage. Then, there is, of
course, the matter of lost power to con-
sider.

There has been more or less difference
of opinion regarding the cause or causes
of this slippage, for so it must be termed,
and a number of theories have been ad-
vzt.^.ed in explanation. The one which
has gained the most general credence is
based upon the observation of the fact
that when a belt operates at a high speed
it seems to leave the driven pulley so
that it is often possible to see between
the belt and the pulley.

According to this theory the high speed
of the belt causes air to be drawn in
under the belt, forming an air cushion
between the pulley and the belt, upon
which the belt rides, skimming around
the pulley instead of coming into close
contact with its face. This theory holds
that the rotation of the pulley is due to
the friction between this revolving air
cushion and the face of the pulley.

If this theory is correct, obviously the
solution of the whole trouble is to do
away with the air cushion which pre-
vents the belt from coming into close
contact with the face of the pulley.

It would seem that the easiest way to
accomplish this would be the introduction
of a small deflecting shield in front of
the pulley, and so placed that the belt
would just pass without touching it. If
any air current existed this deflector
wruld surely break it up and prevent its
going under the belt, which it does ac-
cording to the theory. If this method
has ever been suggested, it does not seem
to have gained any foothold.

The most popular method of doing
away with this so called air cushion is
the use of pulleys the rims of which are
perforated to permit the air to pass
through, or grooved circumferentially to
permit the air passing out under the belt.
A number of manufacturers make and
exploit these perforated and grooved pul-

By Karl W. Knorr

Slippage uitli high belt
speeds is not due to an air
cushion being dra'dii he-
liceen belt and pulley hut
to the action oj centn'jugal
force -lehich stretches the belt
and tends to make it rise
o]j the pulley face.

leys, but they do so probably because
there is a demand for them rather than
because they believe there is any real
merit in the idea.

For a cushion of air to force itself be-
tween a belt and the pulley over which
this belt operates, it must have sufficient
pressure to overcome the pressure of the
belt on the pulley produced by the initial
belt tension and the load tension.

In the character of service where high
belt speeds are more generally used, viz.,
motor and generator work, both the ini-
tial and the load tensions are, as a rule,
very high, so that the air must be under
considerable pressure to lift the belt from
the pulley.

For illustration, take a 10-inch belt
running over a 16-inch pulley. An initial
tension of 40 pounds and a load tension
of 60 pounds per inch in width of belt is
a modest assumption, for in practice the
figures will run nearer 60 pounds initial
tension and from 90 to 120 pounds load
tension. However, for illustration, it is
desirable that the figures be conservative
rather than high. Taking the figures as-
sumed, it will be seen that the total pres-
sure on the pulley per inch in width of
belt is 140 pounds, this being the sum of
the 40 pounds initial, the 60 pounds load
tension on the tight side of the drive, and
4/1 pounds initial tension on the slack
side of the drive. The belt is 10 inches
wide, so that the total pressure of the
belt upon the face of the pulley is 1400
pounds, and as the projected area of the
pulley is 160 square inches, the pressure
of the belt per square inch of projected
area is 8' i pounds.

In order to form a cushion under the
belt, the air must not only overcome this
heavy pressure, but it must also have
sufficient extra pressure to produce the
added tension necessary in the belt to
straighten out the catenary curve in
which it hangs, and by thus reducing the
sag permit the belt to ride on the sur-
face of the cushion, or the extra pressure
must he sufflcient to stretch the belt

enough to allow it to ride on the
cushion. The cushion of air has the
effect of increasing the diameter of the
pulley so far as the belt is concerned, and
its presence, therefore, necessitates an
increase in the tension of the belt, re-
ducing its sag between the pulleys, or
causing a stretching of the belt.

The tension necessary to produce either
of the results mentioned is considerable,
so it will be readily seen that the pres-
sure of the air forming the cushion must
be extremely high.

If the belt w ill produce a current of air
on its under side which will attain the
extremely high pressure necessary to
produce the results claimed, why will
there not be a similar stratum of air on
the other side of the belt? That this is
not the case is shown by the absence of
results which would accompany a stream
of air at from 9 to 12 pounds pressure
per square inch, and of a width equiva-
lent to that of the belt. One would not
have to get very close to such a stream
to be made fully aware of its exist-
ence.

It would seem fair to assume that if
the current of air under high pressure
does not exist on the outside of the belt
it does not exist on the inside; but even
if it does, it is difficult to conceive why
this current will not rush out sideways
when it strikes the face of the pulley,
taking the line of least resistance instead
of overcoming all the resistance offered
by the belt and going under it.

Then, too, if the air does go under the
belt, why will it run through holes or
grooves made in the rim and not out the
sides of the belt?

Another point which seems strange is
that the cushion always forms on the
driven pulley. If the current of air
exists, would it not pcrfonn in the same
way on the driving pulley as on the
driven ?

A consideration of the effects of cen-
trifugal force develops what would seem
to be a rational explanation of the phe-
nomenon. The stretching of the belt is
due to centrifugal tension, the belt com-
ing in contact with the driven pulley at
frequent intervals, thus driving it, but
jumping away frequently enough to pro-
duce the illusion of running on air.

There is no question of the existence
of such a tension to figure the amount of
which Rankine gives the following rule:
If an endless band, of any figure whatso-
ever, runs at a given speed, Ihc centrifu-
gal force produces a uniform tension at
each cross-section of the hand, equal to
the weight of a piece of Ihc band, whose
length is twice the highl from which a
heavy body must fall, in order to acquire
the velocity of the band.

Fn the case of a leather belt, this ten-

692

POWER

November 7. 191 1

sion produced by centrifugal force can
be expressed by the formula

T = 0.012 V\

where T equals the centrifugal tension
per inch in width of belt, and V equals
the velocity of the belt in feet per second.
Using this tension and a fair average
value of the coefficient of elasticity of
leather, the formula for the stretch of
leather belting assumes the form

S = 0.00000049 L V,
where

S = Stretch in inches,
L = Total length of belt in inches.
F;= Velocity of belt in feet per
second.

That the trouble is due to the stretch-
ing of the belt produced by centrifugal
tension is borne out by the following:

The lower the belt speed the lower
will be the centrifugal tension, and, con-
.sequently, the less will be the belt stretch.
It is, therefore, necessary that the belt
be kept up to speed if there is to be any
stretch due to centrifugal tension so the
belt must necessarily hug the driver
closely and the stretch, if any, must all
be evident at the opposite end of the
drive. This agrees with observed facts.

As the centrifugal tension is reduced
with the speed, it is probable that there
should be a speed below which the ten-
sion will not be sufficient to produce ob-
jectionable results. It has been found
in practice that if belts are run at speeds
rot exceeding 4500 to 4800 feet per min-
ute, no trouble is experienced on account
of undue slippage.

If centrifugal tension causes slippage,
the clearance between the driven 'pulley
and the belt should increase with the
speed of the belt. This has been ob-
served to be the case in practice.

Also, if this trouble is due to increased
length of belt due to centrifugal tension,
it should be possible, after getting the
belt up to speed, to eliminate the clear-
ance between the belt and the driven
wheel by backing the latter up to the
position maintained by the belt. This is
also true in practice. Of course, when
the belt is stopped and the centrifugal
tension eliminated, the driven wheel must
be pulled forward again. When the belt
is in motion the centrifugal tension
stretches it, and when the belt is stopped
it tends to regain its original length. If
the driven wheel is not pushed forward
when the belt is stopped, the elasticity
of the belt tending to bring it back to its
normal length will produce an enormous
pressure on the bearings, and the belt
will be under excessive internal strain
while at rest. With generators and
motors it is no great trouble to run the
pulleys back into the belts, or pull the
belts into the pulleys, because thev are
mounted in sliding frames with adjusting
screws.

The foregoing is without doubt the
real solution of belt slippage with high-
speed leather belts.

A means of overcoming the trouble and
at the same time doing away with the
necessity of moving the pulleys would
be to use a belt made of some material
which does not stretch as easily as
leather. A steel-band belt is being ex-
ploited to some extent at the present time,
and considerable success in operation is
being claimed for it. As steel will stretch
only about one-thousandth as much as
leather under the same tension, it is ob-
vious that a belt made of this material
would be better for high-speed service
than one made of leather.

Firing Marine Boilers on the
Chicago River

Instructions for firing marine boilers
in vessels without making dense smoke
while in the Chicago river and harbor,
which apply to the average freight
and passenger boat, formulated by Os-
born Monnett, smoke inspector, and Ed-
win F. Oyster, marine deputy, have been
issued by the department of smoke in-
spection of the city of Chicago. While
the advice is given as specifically as
possible, yet there are instances when a
little deviation might bring better results.
What may apply to one boat might not
apply to others, but the instructions are
so general, that freight and passenger
boats having either Scotch marine or
firebox boilers can use them to advan-

reach her dock without again working the
fires.

All further firing while in the Chicago
river should be with Pocahontas coal.

Firing at the Dock

When steam is required, or the fire on
the rear of the grate gets low, push the
coked coal back and quickly charge the
front of furnace with fresh coal. Leave

hn

Fig. 2. Fire Ready to be Pushed Back

the door cracked for short time and keep
the blower on until the top of the fire
assumes a bright red color. Regulate
the steam pressure by the damper. Fig.
2 illustrates the condition of the fire
before pushing it back.

Cleaning Fires in Port

.■\void, if possible, the cleaning of fires
in port. If necessary to do so, clean
quickly and when convenient only one
boiler during an hour.

Throw broken coal in front wings of
the furnace on each side for a distance

Fig. 1. Fires in Condition to E.nter
Chicago Harbor

tage in the effort to eliminate dense
smoke. The instructions are as follow-s:

Coming into Port

Clean all fires before reaching Chi-
cago.

Before entering the harbor, shove the
fuel to the rear of the grates, clearing
about 2 feet of the front of the grate sur-
face; cover the burning fuel with about
4 inches of fresh coal and fill the cleared
space with broken coal almost to the
top of the furnace; leave door cracked
for short interval and put on the blower.
Have all fires in the condition shown in
Fig. 1 when abreast the life-saving sta-
tion. The vessel will then be able to

Fic. 3. Showing Fire after Coked Coal
Has Been Pushed Back

of 3 or 4 feet. Crack the door and use
the blower. Wait until the last charge of
coal is burning well, close the ashpit
door; rake out in front all the old fuel
on the central portion of the grate and
fill the cleared space with well broken-
up coal to a thickness of 4 or 5 inches.
If steam is not required, let the green
fuel catch and get well coked from the
live beds at the sides.

To raise steam more quickly, the burn-
ing fuel at the sides can be winged over
on top of the green coal, .^fter either
operation, open the ashpit door and put
on the blower until the fire gets action.

After the middle portion has ignited
well, rake out the sides, which will be
nearly burned out, charge with fresh,

November 7, 191 1

POWER

693

broken-up coal and allow this to bum
without winging over the center. Crack
the doors and use the blower.

Fig. 5 shows the condition of the fire
when cleaning by this method.

Give plenty of time for the fresh coal
to coke before again disturbing the fires.

Fig. 4. Method of Barring Fires

Do all the cleaning and charging as
quickly as possible in order to preserve
the furnace temperature.

While Shifting in River

A half-hour's notice or more should
be given the fireman before getting under
way in order to have steam enough to
shift without forcing the fires.

Raise steam by stirring the top part
of the fire with a rake and breaking up
the coked portion of the fuel bed; crack
the door and use the blower.

Allow the fire to burn brightly for a
few minutes; push back and put new
charge on the front of the grate. Repeat
as often as necessary to hold steam.

To make additional steam in shifting.
fuel beds may be barred if necessary.
but this should consist only of a slight
raising of the bed and not passing the
bar up through it, as clinkers will mix
with the fuel, spoiling the fire and mak-
ing smoke. See Fig. 4.

Lumps of fuel charged should never
be larger than one's fist.

A. rcnlrnl imrlloii of grnlp nfir'
rlvflnnl (lilt and fliiiri!«l with fii"<li loni /(.
wlnza "f fiirnnii- rli-nnml iiinl rhnrir'il wHIi
frcah roal nftpr contrnl iiorllnn of fnH l«<l
h«« litnlKHl.

Cracking of the doors consists in the
doors being opened not over 1 inch and
as they are opened for short periods
of time only, the flues will not be af-
fected.

While in the river, fires must be car-
ried very thick at all times. If the fires
are allowed to burn down to 3 or 4 inches

at the dock, it will be impossible to make
steam without making smoke.

Starting Fires

Cover the bare grate with well broken-
up coal to an average thickness of about
4 inches. Then put five scoops of live
coal on the top at the bridgewall as
shown in Fig. 6, and close the fire door
with the damper open. Fire will burn
from the back to the front with much less
smoke by this method than by any other.

Vi'hen the fire has covered the entire
grate, push the fuel bed toward the rear
and fill the front of the grate with fresh
coal to about one-half the hight of the
furnace. This should be left undisturbed
until mostly coked. Crack the door and
use the blower. Shove the coked coal
back and repeat the operation as often
as it is necessary to raise steam.

In all operations where the fire is dis-
turbed, give the fire a little air through
the doors and use the blower.

Burning Pocahontas Coal

This fuel cakes quite easily and to
get the required steam it must be broken

Fic. 6. Method of Starting Fires

up occasionally from the top; use a rake
or a hoe.

Blowing Flues
Flues should never be blown in the
Chicago river.

A Prohlfiii in Stutiis

Recently a quer>- was received as to
the solution of the following problem:

Three men carry a stick of timber, two
taking hold at a common point and the
third at the end. Where should the two
men take hold together so that the load
will be equally distributed among the
three?

The problem is an old one but it still
continues to puzzle many. As its solu-
tion embodies the fundamental treat-
ment of all beams, however, it is here-
with given.

FiG. 1. Timber Balanced

If a man supported the beam under its
center of gravity, it would balance on
his shoulder and he would cari7 the
whole weight, as in fie sketch, Fig. I.

A man standing at one end would bear
none of it. However, as the middle man
moved toward the other end more and
more of the weight would come upon the
end man, until when each was at an
equal distance from the center of gravity
ihe load would be equallv divided, as in
Fig. 2.

1^

u!

Fig. 2. Each Man Supporting Half
the Weight

In all cases the product of the load
carried and the distance of the point of
support from the center of gravity will
be constant. As it is stipulated that the
end man shall carry one-tnira the load
11^, and as his distance from the center
of gravity is half the length of the

timber, or -;, the product of this dis-
tance and his share of the load will be

The other two men are to carry two-
thirds of the load together. Letting their
distance from the center of gravity be
represented by the unknown value .v,
the product of this distance and their
load must be

J 11

X V
But since the product of the load car-

FiG. 3. Load Equally Distributed be-
tween THE Three Men

ried by a support and its distance from

the center of gravity is constant for any

II
given case, then

/. ,2 M
must equal

From which

117. iU

I.

Hence the two men support the tim-
ber at one-quarter its length from the
middle; in other words, three-quarters
of the length from the end supported by
the single man, as shown in the illustra-
tion. Fig. 3.

It is claimed that the first steam der-
rick was used by .lames J. Siivth in build-
ing the New York post oflflcc foundations,
in 1870. Knowing their wide use today,
how did we ever get along without them
up to this late date?

694

P O W E R

November 7. 191 1

Superheating and the Superheater

Recqnt tests on certain high-grade Ger-
man types of combined boiler and en-
gine, with about 200 degrees Fahrenheit
of superheat, showed as high as 25 per
cent, increase in plant power, 25 per
cent, saved in coal and 33 per cent, saved
in boiler-feed water, due to the super-
heating. For the ordinary superheats
used, in Europe at least, an average sav-
ing of 7 per cent, in coal may be as-
sumed.

LlCHTKNING THE WoRK OF THE BOILER

For new installations this saving in
coal ought to be effected without much,
if any, e.\tra cost of the boiler plant, for
the cost of a superheated steam plant is
approximately equal to that of a saturated
steam plant of the same power, since the
superhe?ted plant has less steam to gen-
erate. This will be clear by referring to
Fig. 1, which shows the relative prices
of water-tube boilers and their super-
heaters for different amounts of boiler-
heating surface. The superheaters for
large boilers cost from 20 to 25 per cent,
as much as the boiler itself, so that if
by the use of the superheater the power
nf the plant is increased in like pro-
portion to this extra cost, the super-

By L. B. Taylor

Sit per heat reduces radia-
tion loss and improves the
heat iitilizatiuH in the en-
gine. Another advantage
is reduction in necessary
boiler and condenser capac-
ity with consequent reduc-
tion in feed and condensing
water. A formula is given
for estimating the super-
heating surface required for
a given degree of superheat
and a given set of condi-
tions.

which is another point in favor of low
plant cost.

Since the water space in a boiler is a
measure of the energy reserve, the rela-
tive disadvantage of the small volume
of water in the water-tube boiler is

0 1000 2000 3000 0

Bo'iler Hea+ing Surface.

lOOO 2000 5000 400O

Boiler Hea+ing Surface fo-ia

Fig. 1. Approxi.mate Cost (in Germany) of Boilers and Superheaters

heated plant will cost no more than the
saturated plant of the same power.

.Mthough the advantage of superheat-
ing is principally due to the engine or
turbine operating on the superheat, under
certain conditions there is aiso an im-
provement in the heat utilization in the
boiler, for when saturated steam is heated
at constant pressure its volume increases,
hence a boiler with the same amount of
boiler-heating surface will generate more
superheated steam, measured by volume,
than saturated steam. It is a common
error, however, to assume that with super-
heating a better heat utilization in the
boiler is obtained under all conditions,
for this is not always so. The better
heat utilization depends- greatly on the
boiler load and is sometimes very small.
■ This should be considered in determining
the size of the boiler. A boiler for super-
heated steam may be smaller than one
for saturated, to give the same power.

diminished by the employipent of a
superheater, for this helps to store en-
ergy. Internally fired boilers \yith their
large water space have less to gain in
this respect. Superheaters are useful
with water-tube boilers in drying out
the moist steam generated, since this
type of boiler has a relatively small
steam space which is the measure for the
dryness of the steam. Another advantage
of superheating is the elimination of
loss due to condensation in the piping.

The reduction of the pipe loss and
the thermal loss in the engine, which is the
same as increasing the thermal efficiency,
is obtained because the loss due to cool-
ing until the steam reaches the saturation
limit is taken from the superheat and not
from the latent heat; hence no con-
densation is caused. This is clearly the
principal economic reason for using
superheat. Superheated steam has the
same economical importance for long

steam-pipe lines as it has for the prime
mover. By using high pressures and high
superheats, and then by stepping down
with reducing valves at destination, small
pipes and high velocities (twice that for
saturated steam) can be used, resulting
in a low first cost and in small heat
losses, so that transmission of steam for
distances of from 6000 to 10,000 feet has
recently been made possible.

Increasing Thermal Efficiency of the
Stea.m Engine

Superheating, besides increasing the
volume of the steam, results in an im-
proved steam consumption in the engine,
especially at fractional loads. This im-
provement is explained in Schule's
"Thermodynamics" as follows:

In a steam engine working on the
ideal process, by the use of superheat a
somewhat larger part of the total heat
supplied by the steam is converted into
work, for the same initial and final pres-
sures and the same back pressure. For
steam pressures between 90 and 120
pounds per square inch, the difference in
the thermal efficiency is from about 6 to
about 4 per cent, in favor of the super-
heated steam. With increasing steam
pressures this difference decreases still
more. Such slight saving would in gen-
eral be too small to make it worth while
to install a superheater and to warrant
the expense necessary- for operating on
superheated steam.

The actual improvement is, however,
considerably greater than would be ex-
pected from theoretical reasoning. This
is true because of the much smaller
losses due to the cooling of the super-
heated steam as compared with saturated
steam. The superheated steam loses
heat to the cylinder walls during admis-
sion, but so long as the whole superheat
is not lost, no moisture formation occurs.
The steam contracts during the cooling
down, but the loss in work produced
thereby is much smaller than if a part of
the steam, as with saturated steam, went
over into the liquid state and thereby en-
tirely lost its capacity for work. The
much smaller heat conductivity of the
more gaseous superheated steam, com-
pared to the moisture-laden saturated
steam, results in a decrease in the cool-
ing-down losses. Consequently, with
otherwise similar conditions, the opera-
tion with superheated steam gives a bet-
ter engine efficiency and, in general, a
higher commercial efficiency. Even a
moderate superheat, which can be used
in an engine originally built for saturated
steam, may produce such an important
saving that it will warrant the installa-
tion of superheaters in a plant already
existing.

In practical operation a steam cylinder
of a given size with a given point of

November

1911

POWER

695

cutofr and a given initial pressure will
develop less power with superheated
steam than with saturated steam be-
cause the expansion line for super-
heated steam falls more rapidly. This
fact does not conflict, however, with the
fact that better utilization of the heat
is obtained with superheated steam.

To overcome the effects of cylinder
condensation, steam jackets, requiring a
weight of steam amounting to from 10 to
12 per cent, of the operating steam, are
used when running on saturated steam.
Only low-speed engines are improved by
these jackets. With medium and high
superheat the jacket is not regularly re-
quired and is used only for starting up.
as otherwise the lubrication of the piston
guiding surface is endangered.

Cylinder and pipe condensation is
avoided because of the fact that super-
heated steam is a poor conductor of
heat; the coefficient of heat transmission
at 100 feet per second steam velocity
amounts, on the average, to only 1/12
of that of saturated steam. Furthermore,
superheated steam can give up a part of
its heat (from Fig. 2 1 for a superheat
of 650 degrees, about 10 per cent, be-
fore it becomes satrrated and begins to

■~0 50 100 150 eOO 250

Si-eom Pressure. Pounds Absolute *~"

Fic. 2. Total Heat in Saturated and
Superheated Steam

deposit as moisture on the cylinder or
pipe walls.

An experiment proving how poor a
conductor of heat superheated steam
really is can be made with a sr'.all copper
flask the bottom of which is first heated
red hot over a bunsen burner. The flame
is then removed and -i test tube full of
water is poured in and the opening
closed lightly with a cork. It will be a
surprisingly long time before the layer
of superheated steam immediately
formed between the water and the flask
will allow enough heat to pass to boil
the water, which finally flashes complete-
ly into steam, blowing out the cork with
considerable force.

The reduction in the quantity of cool-
ing water required with condensing en-
gines and turbines, made possible by
the improved steam consumption, means
much if the cooling water is difficult to
obtain. It is true that the steam on

leaving the engine or the turbine will be
drier (up to perhaps 8 per cent.! if
originally superheated, but the quantity
of steam used will be reduced in a con-
siderably greater ratio, so that the total
quantity of heat to be abstracted by
the cooling water, and consequently, the
amount of cooling water required, will
be considerably reduced.

Since a drop of water acts like a
solid body on the steam-turbine blading
when entering with the steam, super-

•5

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!

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s

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i
j.-4aooo

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Cast Iron

Sjcuxx)

—

H ICKXW

1

-.,

1

->

0 I00 20O3O04O05OO6OO700 8OO
Temperature. C>e9rees Fahrenheit '^'*^

Fig. 3. Effect of Temperature on Ten-
sile Strength of Various Metals

heating, by avoiding the moisture, pre-
vents erosion of the blades. Turbines
running on superheat have been operated
for as much as 25,000 hours without
showing any noticeable wear or any in-
crease in steam consumption.

Depending on the type of engine, low
superheat, up to 50 degrees is used if
it is simply desired to dry the steam;
medium superheat, up to 150 degrees
may be used in engines with sliding
valves, and high superheat up to 250
degrees in turbines and special recipro-
cating engines. Impulse turbines with
their ample blade clearances allow some-
what higher superheats than do reaction
turbines.

The 250 degrees of superheat means
an actual temperature of nearly 650 de-
grees. This is the highest superheat thus
far attempted, for referring to Fig. 3,
which shows the effect of high tempera-
tures on the tensile strength of certain
metals, it will be seen that a rapid re-
duction in the strength of steel and cast
iron would result if the temperature were
carried any higher. Fig. 4 shows the
effect of high temperatures on the resist-
ing force between lap-welded steel pipes
and their flanges of cast and open-hearth
steel.

Types of Superheaters

The separately or directly fired super-
heater, one superheater for many boil-
ers, is used but little today; when fired
with coal due to its large radiation loss
(bad heat utilization) and the difflculty
of opcraling on Ructualing loads. This
diflflcullv is due to the large amount of
heat stored in the brick walls surrounding
the superheater, which continue to give

up the same amount of heat, to the re-
duced quantity of steam in the super-
heater, regardless of any reduction in the
heat of the flames. The temperature of
the steam may thus rise beyond control
and completely burn out the lubricatior
of the engine or fatally distort the tur-
bine casing. This type, however, is still
used in steel mills where waste gases are
to be utilized, or where oil firing is used.
The boiler-draft superheater, placed in
the current of hot gases in the boiler, is
cheaper in first cost and in operation, and
adapts itself more automatically to the
fluctuations in the power demand, so that
this is the modern arrangement of the
superheater and the only one here to be
considered.

Superheater Construction

The Schwoerer type of superheater
with cast-iron pipes 7'.. inches inside
diameter, provided with cross ribs out-
side and longitudinal ribs inside, is sim-
ple and reliable, being but little affected
by uneven heating (by warming up and
by sudden shutting off of steam). The
greater area of the outer ribs is re-
quired because rhe transfer of heat from
the hot gases to the wall is more difficult
than from the wall to the steam.

The seamless-tube type, with tubes
usually 1 inch to 1 1 inches inside diam-
eter and 0.16 inch to 0.20 inch thick, is
more common of late and is cheaper than
the cast-iron type; but it must be started
up with care. The circular form, wound
in a plain spiral or in a helical coil,
brings the steam particles to whirling,
so that the moisture is thrown against

£6(i(X»

Esoooo

?3Q0OO

-jaooo,

2j22hi2i-

S2S^

\

■>,fj

R^.

s

->

N

N

600 600 TOO 800

TcmperoturcOegrfres Fahrenheit. '•'"**

Fig. 4. Force Required to Remove

Flanges Pressed on Hydraulically

FROM Lap-welded Steel Pipe

the heating wall. Change of lirection
improves the transfer of heat from the
wall to the steam. Straight and U-formed
tubes are also used. If vertical, they are
difficult to drain of the water, if hori-
zontal, volatile ash is apt to collect on
them. In all cases, they must be per-
fectly free to expand.

Twisted, cross-shaped bars rolled into
the tubes reduce by one-half the maxi-
mum distance of a steam particle from
the metal wall and increase the heat
transmission by 40 to 50 per cent.

Counter or Parallel Flo«
As long as the moisture carried over
with the saturated steam (about 2 per
cent, for a firc-tubc boiler and from 3 to

(396

P O W F. R

November 7. 191 1

4 ptr cent, for a water-tube boiler) ex-
ists, it is best to use a countercurrent
action. It tends to sliorten the life (dur-
ability) of the superheater, especially
with flue-gas temperatures above 900 de-
grees Tahrenheit, but reduces the heating
surface required by 15 to 30 per cent.
To insure effective action of the heat-
ing surface, dead corners of the hot-gas
currents should be avoided. For super-
heaters subjected to heavy duty, com-
plete elimination is recommended.

Attention REQUiRKn by a Superheater

Firing up causes great stress in a
superheater, because it is heated by the
hot gases without being cooled by any
flowing steam. If the superheater lies
in a compartment, the hot-gas currents
should be directed away from the com-
partment by closing a swinging or slid-
ing damper of fireclay or cast iron. Steel
superheaters not lying in compartments
can be protected against burning by
flooding with water. This should be care-
fully drained off so that no water is car-
ried over into the engine or turbine.

Cleaning is desirable once or twice
daily as soon as the temp.erature of the
superheated steam begins to drop; this
may be done by powerful jet blowers
which remove from the tubes the soot
and volatile ash which affect the heat ab-
sorption to a high degree. The clean-
ing holes in the brickwork must close
tightly. If the cleaning of the soot and
volatile ash from the main boiler tubes
is neglected, the hot gases reaching the
superheater will not be cooled as much
as they should and may overheat the
superheater tubes, thus causing them to
split. Even with the nia.ximum forcing
of the boiler, the hot gases on reaching
the superheater should not exceed 1500
degrees.

The pyrometer in the flue-gas draft
and the thermometers in the currents of
steam should be regularly observed and
the safety valve should be tested for
proper operation. If regulation of the
steam temperature is required, it may
be done either by adjusting the damper
shutting off the superheater compart-
ment or by mixing the steam from the
superheater 'with the saturated steam
from the boiler. For the latter, powerful
stirring is needed for both kinds of steam.
The method of injecting purified water
into the superheater is now but seldom
used.

Amount of Heating Surface

The proportioning of the heating sur-
face of the superheater is often done
from data obtained from practice, es-
pecially in case we deal with a plant
similar to several previously built. In
such cases it suffices to estimate the
superheater heating surface on the basis
O'f the boiler heating surface and the
grate area. Fig. 5 shows the required
superheating surface in percentage of the

boiler heating surface of a normally op-
erated water-tube boiler for any desired
degree of superheat. It is based on the
assumption that one-half of the boiler-
heating surface lies in front of the super-
heater. Here the percentages range from
10 to 40, while some authorities recom-
mend from 10 to 25, if less boiler sur-
face is previously used.

For internally fired boilers, a super-
heater heating surface of from 50 to 100
per cent, of the boiler heating surface
is required. For long-flaming, bituminous
coals with much volatile matter, the heat-
ing surface of the superheater can be
chosen somewhat smaller.

In respect to the grate area, the super-
heater heating surface for internally fired
boilers is about 30 times and on water-
tube boilers about 10 times the grate
area.

The heating surface of the superheater
will be smaller, the higher the tempera-

c 650

%y

y

/

Water

Tube Bo

ilery^

^

/

y^

'^

25

FerCen+. '•—^

Superheater Heating Surface m
PerCent.of Boiler Heating Surface

Fig. 5. Relation between Superheating
Surface and Boiler-heating Sur-
face

ture of the hot gases surrounding it;
that is, the less boiler heating surface
utilized before the superheater is reached.
The superheater, however, should not be
placed in the region of the hottest gases,
even if the superheater must be made
larger thereby, for it is then better pro-
tected and lasts longer. Enough boiler-
heating surface should be previously
utilized, so that the hot gases on reach-
ing the superheater, even by the maxi-
mum forcing of the boiler, do not exceed
a temperature of 1500 degrees.

Fig. 6 gives the probable range of the
temperature of the hot gases on entering
the superheater for normally loaded
water-tube boilers using anthracite, and
for any percentage of boiler heating sur-
face previously used. For internally
fired boilers of the usual length it can be
assumed that the entering temperature
of the hot gases is from 900 to 1100 de-
grees. For heavy forcing and for bitumi-
nous coal, the temperature of the hot gas
on reaching the superheater will he
higher.

Where the data derived from practice
do not suffice, it is possible to figure
the surface from the formula

K X tm

where

A = Required area in square feet.

Q = Total quantity of heat in B.t.u. to
be added to the steam per hour, deter-
mined by the aid of Fig. 2.

tm -- Difference in degrees Fahren-
heit between the mean hot-gas tempera-
ture and the mean steam temperature;
that is, the mean between the tempera-
tures of the saturated and the super-
heated steam. The preliminary deter-
mination of the mean temperature of the
hot gases surrounding the superheater is
somewhat uncertain. This will be dis-
cussed later in an example.

K = Coefficient of heat transmission;
that is. the B.t.u. passing through 1
square foot of surface in an hour for
each degree difference in temperature.
Its value is somewhat uncertain for the
different uses of the superheater, since
the infiuence of the various factors en-
tering into its determination are not as
yet sufficiently explained. It appears to
depend but little on the velocity of the
steam if this exceeds, as it usually does,
30 to 50 feet per second, but probably
it increases with the temperature of the
hot gases and therefore with the load
on the boiler. Powerful whirling of the
gases caused by a staggered arrangement
of the heating tubes increases the heat
transmission. Furthermore, the heat
transmission in actual operation is dif-
ferent from that of tests, since the super-
heater in operation is always covered
more or less with soot and volatile ash.

g> 1200
glllOO

■3 '^1000

j

7\

Water Tube BoiterjM

m

1

^^' ■ y

^"^ .^^^

<J o 800

|l700

E

^ 600

-"""^^ 1

G5

60 55 50 45
Percent,
r Heating Surface Used
eacninq

-W

before Reaching Superheater.

Fig. 6. Probable Temperature Range
OF Gases Entering Superheater
after Passing over a Given Per
Cent, of Boiler-heating Sur-
face

/C = 2 to 3 for cast-iron superheaters
for internally fired boilers.

/C = 1 to 5 for steel superheaters for
water-tube boilers, depending on the man-
ner of building into the boiler and the
intensifying of the boiler-heating surface.

K = 8 to 10 for locomotive and sep-
arately fired countercurrent superheaters.

Superheater for Water-tube Boiler
For the purpose of illustrating the for-
mula let it be required to determine the

November 7, 191 1

P O W E R

697

superheating surface for a given water-
tube boiler with the following data:

Steam pressure. 180 pounds gage;
boiler heating surface, 2500 square feet;
required temperature of the steam, 650
degrees; steam generated per square foot
of boiler heating surface per hour, 5
pounds; quality of the steam, 97 per
cent.; heat value of the coal, 13,500 B.t.u.
per pound; temperature of the hot gases
on entering the superheater. 1100 degrees.

The heat to be added per pound of the
steam for the superheat (see Fig. 2)
equals 147 B.t.u. Since there are

5 X 2500 — 12,500 pounds of steam
generated per hour,

12.500 \ 147 = 1.837,500 B.t.u.
will be required for superheating. To
do' out the 3 per cent, of moisture car-
ried over by the saturated steam (whose
latent heat equals about 851 B.t.u.),
0.03 X 12.500 X 851 = 319.125 B.t.u.

per hour
will be required in addition, so that the
total quantity of heat to be given up to
the superheater equals 2.156.625 B.t.u.
per hour. Increasing this by 8 per cent.
to cover the radiation lost from the brick-
work near the superheater, we have the
heat to be abstracted from the hot gases
1.08 X 2,156,625 = 2.329.155 B.t.u. per

hour
from which we can now figure the tem-
perature of the hot gases on leaving
the superheater as follows:

The coal consumption per hour (on the
basis of 8 pounds of steam per pound of
coal) equals

I2.SOO , ^ ,

— ; - = IS"-' />PH»«/,t per hour

The weight (referred to standard condi-
tions) of the combustion gases developed-
per pound of anthracite, when using ap-
proximately 70 per cent, excess of air.
will be 21 pounds with a specific heat of
0.24. The amount of excess air was
determined on a similar boiler without
superheat from the CO. recorder which
read 11 per cent, of CO. in the flue gas.
The flue-gas temperature, t.. on leaving
the superheater is figured from the equa-
tion

0.24 X <1100 — /:) X 1562 X 21 =
2.329.155 B.t.u.
from which

/; — 804 degrees

The average temperature surrounding

the superheater equals

I loo -f 804 r L L ,
^ 952 degrrrs l-iihrcnhrU

The average temperature of the steam
in the superheater equals

^^^ + fiso , r u I ,

^512 Jfgrcci r nhri nhcU

The mean difference in temperature
between the hot gases and the steam
equals

9S2 — 512 -- 440 degrees

Assuming a coefficient of heat trans-
mission of K 5, the heating surface of
the superheater will be

2.T,2<}.\'.S

Wrouj^ht Iron Castings

To meet conditions requiring lightness
combined with strength, wrought-iron
castings are now being used to a large
extent. As the name implies, they are
made by melting wrought-iron scrap and
then casting. The process has been em-
ployed in Germany for the past six or
eight years, but has only lately been in-
troduced here.

Recently a patternmaker's mistake af-
forded an opportunity for subjecting one
of these castings to a severe test

/

r

Ron BEFORE AND AFTER TURNING

In assembling and finishing the pattern
for a connecting rod, the bores of the
jaws and the eye for the crank pin were
placed at right angles. This error was
not discovered until after the rod was

It is claimed that these castings
possess all the properties of wrought
iron; that they are soft to machine; can
be bent hot or cold, hammered, welded
and hardened; and show a tensile
strength of 50,000 to 75,000 pounds per
square inch, with an elongation of 15
per cent, and a reduction in area of 35
per cent. They are made by the Wrought
Iron Casting Company, of New York
City.

Fireproof Oil Storage House
Bv F. B. Hays

The careless storing of oils, paints and
similar inflammable materials increases
the fire-insurance rates and exposes the
surrounding buildings to a constant dan-
ger of destruction from fire or explosion.
Fires of this nature are not affected by
water, and must necessarily be permitted
10 burn out. In so doing, they frequently
not only burn the materials themselves
hut also surrounding property, thus caus-
ing considerable financial loss.

A Western manufacturing company has
designed and built on the grounds of its
plant, an oil house for storing such in-
flammable materials, which it claims will
not only prevent the spread of the fire,
but will also put it out.

This structure is built entirely of con-
crete, except for an air-tight steel door
and a steel ventilator on top, as may be
seen by reference to the accompanying

o ^- ■

Plan and Eli;Vation of Stohage Hoish

.5 X 440

= 1059 iijliatr jirt

finished and hahbiited ready for assemb-
ling.

To save time and labor and without
any suggestion (mm the foundry which
made the casting, the rod was healed in
a blacksmith's fire and turned 90 de-
grees to bring the bores in line. There
was not the least »iRn of fracture and
the rod is apparently as strone as if it
had not been twisted.

Pipe fittings made by this process rc-
cenilv withstood severe tests siucccs«fully.

illustrations. The door is so hung that
its weight keeps it closed, and the only
possible ingress or egress nf air is through
the ventilator on thr roof This ventilator
is held open by a piece of fuse wire, and
in the event of fire starting in the house,
the fuse wire would melt and the venti-
lator would automatically close, prevent-
ing the escape of the gases and smoke
and the admis.«ion of air necessary for
further combustion, which, of course,
would cause the fire to soon die out.

(598

POWER

November 7. 191 1

Power from Compressed Air

In the transmission of compressed air
local conditions are the all-important fac-
tor, and these conditions will affect the
laying out of the pipe line to the same
extent as in power-station design in dif-
ferent parts of the country.

The loss of head or pressure has been
found to be proportional directly to the
density and the length of pipe, as the
square of the volume discharged and
inversely as the diameter in inches. In
other words, the economy of transmission
depends, exactly as in the transmission
of direct-current electricity, on how much
capital is to be tied up in the first cost.
For example, in driving the Jeddo mining
tunnel a 6-inch main was used to con-
vey air power to two 3 '4 -inch machine
drills over a distance of 10,900 feet and
the loss of pressure was only 0.002
pound, a practically negligible loss. How-
ever, it would not be economy usually
to design a pipe for such low velocity
of the air, as the interest and deprecia-
tion on the additional investment over
the cost of a smaller pipe line would
more than counterbalance the saving in
fuel, unless a future demand should
make a decided change in the conditions.
In designing the transmission line,
therefore, reasonably definite considera-
tion must be given to the future. The
pipes, as a rule, are run underground,
and are difficult and costly of access. It
costs to pass a certain volume of air
through a length of l-inch pipe over
three times the head necessary to carry
the same volume through the same length
of 2-inch pipe, for the periphery in-
creases as the first power and the area
as the second power of the diameter.
Therefore, as the demand comes on for
extra power and an extra pipe is re-
quired, the loss of head in the two pipes
would be greater than the loss occasioned
by a single pipe of an internal area
equal to the sum of the areas of the two
pipes. The ratio of the periphery to
the area of the transmission pipe is the
important point affecting friction loss of
head. Besides the diameter, the factors
affecting loss of head are: The condi-
tion of the inner surface, the kind of
lo.nt employed, the number of valves and
bends, and other factors of like nature.
Although a number of tests on the mains
in Paris and elsewhere have been made,
the data obtained have not been full
enough to enable any but approximate
calculations. The allowable velocity, how-
ever, was clearly brought out. In each
case with an initial pressure of 100
pounds, it was found that a loss of 2 4
pounds per mile in the pressure oc-
curred with a velocity of 25 feet per sec-
ond, 9.4 pounds per mile with 50 feet
per second, and 46.2 pounds per mile
with a velocity of 100 feet per second

By H. Macintire

Air transmission in pipe
lines. Developing power
from an air system. The
economy obtained and the
possible applications.

Many of the precautions taken in lay-
ing out a steam-pipe line are required for
air transmission. The joints must be
carefully made so as to prevent air leaks
and to eliminate friction as far as is pos-
sible; allowance must be made for ex-
pansion and contraction, especially if the
■pipe is carried above ground; pockets in
the line without means of emptying the
segregated moisture must be avoided, and,
finally, provision must be made for re-
pairs on the pipe should these be neces-
sary.

Some time ago, when the question of
air versus electric power was being con-
sidered, one important argument in favor
of air was that the steam engine could be
used with but slight changes in the valve
gear when operating with air instead of
with steam as the working medium,
whereas, of course, electric power re-
quires absolutely new machinery. The
indicator diagram for air is almost ident-
ical with the steam diagram. When used,
however, as is done now almost entirely,"
to drive special tools, this argument in
favor of air will not hold, as pneumatic
tools have been designed for air power
only.

In general, then, it can be said that
the air motor, or machine, is one spe-
cially designed for the working fluid. The
pneumatic tool cannot be easily described
because of the great diversity in the
varieties of makes. It uses, however, a
pump diagram; that is. it takes air for
the whole stroke, exhausts at the end of
the stroke, and in consequence is not
economical.

Moisture in the air has harmful effects
during expansion unless some means can
be had to prevent the temperature from
going below 32 degrees Fahrenheit. Dur-
ing expansion the temperature drops,
the expansion being almost exactly
adiabatic, td a greater or lesser degree,
according to the conditions. With an
initial pressure of 75 pounds, and using
a pump diagram, the discharge tempera-
ture will be —60 degrees Fahrenheit,
but when expanding to the back pres-
sure an economical diagram will be ob-
tained and the temperature will be — 144
degrees Fahrenheit. This reduction of
temperature is very inconvenient because

of the impossibility in practice of re-
moving all the moisture in the air, and
of the remainder freezing during ex-
haust. This fall in temperature can be
prevented by injecting steam into the air
at admission or by reheating. In the
case of the addition of steam, its latent
heat is given up during expansion and
the temperature of exhaust can be kept
above 32 degrees Fahrenheit. However,
in many cases steam is not available; if
It is available it can be used to drive the
motor itself.

The second method— that of reheating
—IS ver\' practical. A coil of pipe sim-
ilar to those used for superheating steam
IS usually placed over a coke or charcoal
fire and the air is increased some 300 to
400 degrees in temperature at constant
pressure. As, however, dry air is slow
in taking up heat from dry walls, water
IS sometimes sprayed in. The effect is
twofold: First, the troublesome fall be-
low the freezing point is avoided, and.
second, a great increase in efficiency is
obtained. The increase in work is about
six times what could be obtained from a
first-class steam engine at a minimum
first cost. Prof. J. T. Nicholson in ex-
perimenting with a 27-horsepower Corliss
engine, with air at 53 pounds, found
that 850 cubic feet of free air was re-
quired per horsepower-hour, and dry re-
heating to 287 degrees Fahrenheit re-
duced this to 640 cubic feet, or a gain of
25 per cent. The same test showed that
1.42 pounds of coke per hour were re-
quired for each additional horsepower, a
result which will compare very favorably
with good steam-engine practice.
Economics of Air Transmission

So far the discussion has been con-
fined to the means of obtaining power
from an air system and certain prob-
lems arising therefrom, but now the
economics of its use and an idea of its
possibilities will -be considered. The best
Idea of its economy can be obtained from
the plant in Paris, which has been ven-
carefully tested.

These tests have made the Paris plant
very economical. The compressor has
an effTciency of from 75 to 80 per cent.,
the transmission line of 95 to 98 per
cent., and the motor, of the best design
from 75 to 80 per cent. The poorer de-
signs of motors, or those badlv worn or
adjusted, will show as low as 10 per
cent. The Paris plant therefore shows
that good economy can be obtained with
air as the motive power.

Not only is the economy ver\- high,
hut the uses to which air power can be
put are almost without number. These
include all kinds of mining tools, the
pneumatic tools used in ship, bridge and
boiler construction: pneumatic engines
for mining and power-mill traction work.

November

1911

P O ^' E R

699

subway and tunnel work where com-
pressed air is used to prevent the ingress
of water; for refrigeration to a small
extent, and as a means of pumping water
(as in the Pohle air lift).

The advantages of using air are many:
It is cheap; there is no danger of ex-
plosion from air alone; it is reliable; no
insulation is required, nor will the trans-
mission line heat its surroundings. In

Cylinder Oil

In many cases oil is bought entirely on
the basis of its physical test without due-
regard to its ultimate merit, which can he
determined only by its actual perfonn-
ance in the particular case for which it
is to be used. The following example
points out that an oil, although showing
a good "physical test." could not do the
work reasonably expected of it because
the service for which it was intended was
so out of the average that an actual op-
erating test alone was the only proper
way to explain why a large amount of
lubrication was necessary, and why fig-
ures consistetit with good average prac-
tice did not hold in this particular case.
The cylinder oil in question tested as
follows:

.Specific gnuity 26 111

Fla.ih point 560 deKrccs FahrrnliPit

Viscosity IVO si-conds

Cold lest 3.5 degrw.s FahriMituit

It was used on a 16xl8-inch single-
cylinder, noncondensing four-valve en-
gine, running at 220 revolutions per min-
ute, and direct-connected to a 135-kilo-
watt direct-current generator. The ob-
ject of the operating test was to deter-
mine the least quantity of oil which
would properly lubricate the valves and it
was a matter of considerable effort to ar-
rive at a fixed quantity which could be rec-
ommended for general running conditions.

The unit was one of three supplying
light and power to an office building. The
tests were run during two successive
days when the average lighting load was
around 300 amperes, but the elevators
when thrown in produced a swinging load
which often reached as high as 600 am-
peres for a few seconds at a time. Such
an irregular load made a lubrication
problem which was out of the ordinary.
Fluctuating loads reaching nearly 100
per cent, for a few seconds at a time
caused such a reaction on the governor
that the resulting increase in valve travel
demanded a greater quantity of oil than
when the engine was carrying the normal
load. These overloads, while irregular,
occurred at intervals ranging from 40
seconds to 2 minutes. Such conditions
led to a necessarily large oil consump-
tion which, on first thought, seemed lo
be very much against both the engine
builder and the oil man. It was because
the oil dealer saw no reason why mor.-
than one pint of oil in 10 houi^ should
be used that the tests were made.

mining or other confined quarters the
exhaust can be used for ventilation. Air
replaced steam at the Cleveland Stone
Company's works with a daily saving of
about 49 per cent.

The great difficulty is lack of flex-
ibility and large first cost. To design an
economical plant, either the demand for
power must be definite and unvarying
nr the gift of prophecy must be in evi-

dence. Besides this, the size of the pipe
line and the engine is verj' much larger
than electric power would require for
the same power, and the difficulty in
maintaining the transmission line is
greater.

Air power, however, has its own par-
ticular sphere, in mining and quarr>'ing,
and in all probability it will be found
there for some time to come.

Tested for Actual Service

By H. B. Langc

.1 ///;<>» i^// the oil silenced
up well under physical
tests, the load ivas so vari-
able thai the usiial quantity
leas not enough to keep the
valves operating smoothl) .

The amount needed had
to be determined from actual
tests.

In conducting the two tests which were
made on this oil the matter of first im-
portance was not to cut down the oil so
low that the valves would be cut or in-
jured in any way. The "feel" of the
valve rods and the sound of the valves
themselves were the only indications by
which it was possible to determine
whether or not they were getting all the
oil necessary. A distinct vibration or
grinding could be felt on the valve rods
the moment the valves were running dry.
this being caused by their rubbing in the
bore. There was no way of telling
whether an excessive amount of oil was
used; hence the only way was first to cut
the feed so low that the valves ground
slightly and then to gradually increase
it until these indications disappeared. It
was noticed at the start that, although
just sufficient oil was used to run the
valves smoothly for the normal load, the
moment an overload occurred, thus in-
creasing the valve travel and making a
larger rubbing surface in the bore, the
valves would grind at once. Then it was
necessary to increase the feed until the
valves ran just freely on the overloads.

Whenever there was any grinding It
was noticeable that the greatest friction
was in the crank-end exhaust valve, with
less in the head-end exhaust valve, while
the admission valves ran smoothly a' a"
times. For this reason the crank-end
exhaust valve was the one which had lo
be watched the closest.

In order to determine further whether
enough oil was used, the head and ad-
mission valve and the crank-end exhaust
valve were taken out before and after
each '•itn ind the Mcarint' iiirfaccs nf

the valves and the bores were closely ex-
amined for any marks of excessive wear.

Oil was fed by means of one of the
common forms of forced-feed cups, hold-
ing one quart, the stroke of the pump
being regulated by a thumbscrew and
Iccknut on the pump spindle. The com-
parative rates of feed were measured by
holding a rule against the lockout as it
moved up and down and the travel
noted. This travel was equal to the stroke
of the pump and varied during adjust-
ments from ,',; to i\: inch. The total
quantity of oil consumed was measured
by filling the cup to a certain mark when
the tests were started and refilling the
cup to the same mark at the end of the
tests, using a measure of known capacity.

The first test was largely experimental,
various feeds being tried, but a five-hour
run was made, during which time the
average stroke of the pump was ,'.; inch
and 1.928 pints of oil were used, which
was equal to 3.856 pints for a 10-hour
run. The valves on examination showed
no signs of wear after the test and the
oil was well spread over them.

The second run, conducted the follow-
ing day, lasted 10 hours when the aver-
age stroke of the pump was ;- inch, and
1.948 pints of oil were used. During
this run the feed was cut down to the
lowest limit and at times the crank-end
exhaust valve ground slightly. After the
test, when the two valves were removed
for inspection, the head-end admission
valve showed slight signs of wear, but
the oil was well spread over its wearing
surface. The crank-end exhaust valve
could not be removed without using force.
This showed that it was too dry and did
f.ot have enough oil spread over its sur-
face, and it had to be left to cool over-
night. In the morning the valve was
taken out and showed two distinct spots
of wear that were not there before the
run.

From these tests it was found that in
the first run 3.8,S6 pints of oil in 10
hours were more than enough, while in
the second run it was evident that 1.948
pints were too little. Therefore, the test-
ing engineer recommended that about
three pints in 10 hours be used. This
was equivalent to a pump stroke of about
'^ inch and with a hydrostatic sight-feed
lubricator would he about 3' ', drops per
minute.

POWER

November 7. 191 1

^r^
i ,

Oi ^i

^ All %.>

C'atecliism of Electricty
Incandescent Lamps

1 135. How is light produced in an in-
candescent lamp?

By passing a current of electricity
through a conductor so as to heat it white
hot. The conductor that is heated is
called the "filament," because it is in the
form of a thread. The filament is made
very small in cross-section in order to
make its resistance high and thereby re-
duce the current required to heat it.

1136. Does not the filament burn
uivay rapidly from being kepi white hot?

It would if exposed to the air. because
substances heated to a burning tempera-
ture in air are readily destroyed by
oxidation. In order to prevent this, the
filament is mounted within a sealed glass
bulb from which the air has been pumped
out.

the cellulose is forced. This is propor-
tioned according to the required candle-
power, voltage and current of the lamp
filament.

Fic. 381. Carbon-filamEjNt La.mp

1137. What is the usual construction
of the lamp?

Most incandescent lamps are made in
the form shown in Fig. 381. The lamp
comprises three parts, a glass bulb, the
filament and a metal base.

1138. Of what is the filament made?
The ordinary carbon filament is made

of cellulose — a sticky substance com-
posed of cotton and zinc chloride — which
is forced through a small hole to give
it the form of a thread. After being
hardened, it is cut to the proper length,
wound on a form to give it the proper
shape, and carbonized.

1139. What determines the thickness
of the filament?

The size of the hole through which

1 142. Why is platinum used for the
leading-in wires?

Because it does not corrode, and be-
cause the extent to which it expands un-
der the influence of heat is practically
the same as that of glass. There is
therefore no danger of the glass becom-
ing cracked or of its expanding away
from the wires and allowing air to leak
into the bulb.

1143. How is the base made?

This consists of a coarse-threaded
brass shell /;, Fig. 386, in the center of
which is a metal contact o fastened to,
but insulated from, the shell by a cir-

Fic. 382. Different Shapes of Fila.ments Used in Incandescent Lamps

1140. In what shapes are filaments
made?

The shape may be either a plain loop
as at a. Fig. 382, a circular loop as at b,
an oval loop like c, or there may be a
combination of two filaments joined in
series as shown at d, or three filaments
in series as at e, or again the filament
may be made in spiral form as shown
at /.

1141. How is the filament supported
inside the lamp?

Two thin platinum wires c and c, Fig.
383, are fused through a small stem of
glass which is solid at n but hollow at m,
and the ends of the filament are fastened
to c and e by carbon paste. Sufficient
of this paste is used to prevent the heat
of the filament when the lamp is lighted,
from harmfully heating the platinum
wires. To afford additional security, the
filament is anchored at a to a small
platinum wire fused into the glass n.
Small copper wires r and s are fused to
the ends of the platinum leading-in
wires c and e. for connection to the base.
The glass stem n m is fused into the neck
end of the lamp bulb and the air is
pumped out through a small tubular ex-
tension {c. Fig. 384) at the op-
posite end of the bulb, after which
the glass around the opening at
this latter end is fused together, leaving
a small tip projecting outward, as shown
at d. Fig. 385.

Fig. 383.

Method of Supporting Fila-
.ment

cular porcelain piece r. One of the cop-
per wires leading to the filament is
soldered to the brass shell of the base
and the other wire is soldered to the
center contact o so that the two metal
parts of the base form the terminals of
the lamp.

November 7. 191 1

POWER

701

1 144. Hou' is the base fastened to the
bulb .-

With plaster of paris or cement. The
rib / around the neck of the bulb. Figs.
384 and 385. prevents the glass from
pulling out from the base.

1145. How much light docs an incan-
descent lamp give?

From 'j to 100 candlepower, and even
more, according to the size of the fila-
ment. The smallest sizes are used only
for special purposes, such as the decora-
tion of rooms and the investigation by
physicians of throat and nose conditions.
The largest sizes are used for illuminat-
ing large rooms, halls, etc.

Fir,. 384.

Fic. 385.

1146. In what sizes are incandescent
lamps most generally used?

The common sizes are 8, 16, 32 and 50
candlepower. the standard size of carbon-
filament lamp being 16 candlepower.

1147. Are there other kinds of incan-
descent lamps in common use besides
those just described?

Fic.

386. Mfthoo of Fastening Bulb
TO Base

Yes. Besides the lamp with a cellulose
or carbon filament, there are metallic-fila-
ment lamps of which the tantaltim lamp.
Fig. 387. and the tungsten lamp. Fie. ^^■
are in regular use.

1148. What is the object in making
filaments of metal?

The metal filaments are much more ef-
ficient than the carbon filament; that is,
they give more candlepower for each
watt of electrical power.

1149. How do the efficiencies com-
pare ?

The high-efficiency carbon filament re-
quires about 3 watts per candlepower of
light; the corresponding tantalum fila-
ment requires about 2 watts per candle-
power, and the tungsten filament about
1 '4 watts per candlepower.

1150. If tantalum and tungsten lamps
are so much more efficient than carbon
lamps, why are they not used to a greater
extent?

Tantalum lamps and tungsten filaments
are not so satisfactory as carbon fila-
ments, especially where there is consider-
able vibration, because sudden jars and
rough handling are liable to dislodge the
filament from its mounting and cause the
loops to become tangled. Tantalum and
tungsten lamps also cost considerably
more than carbon lamps of equal candle-
power.

FaNTAI IIM-FILAMENT LAMP

1151. Are metal filaments different in
shape and mounting from carbon fila-
ments?

Yes. Owing to the comparatively low
specific resistance of tantalum and
tungsten filaments, they must be made
longer than carbon filaments in order to
make the total resistance of the fila-
ment high enough. This necessitates
mounting the metallic filament upon two
spiders each comprising a number of
small hooks radiating from a glass sup-
port. The filament is loosely wound back
and forth over these hooks so as to form
loops about 1 Inch long in the tantalum
lamp 'see Fig. .387) and about 2 inches
long in the tungsten lamp (Fig. .W8».

11.52. WoM' long does the fitamrnf nf
an Incandescent lamp last?

All of the filaments mentioned will last
.1 Inni' time if not ciiliirrtrd to iars or

excessive vibration, but as the candle-
power decreases with the length of ser-
vice life, the so called useful life is much
shorter than the possible mechanical life.
Up to the point where the candlepower
becomes reduced 20 per cent, (one-fifth
of the original candlepower), the carbon
filament has a life of about 400 to 500

Fig. 3SS. Tincsten-filament La.mp

hours, the tantalum filament about 800
hours on direct current or 600 hours on
aUernating current, and the tungsten fila-
ment about 1000 hours on either current.

1153. As the filaments arc in va.uum
and cannot burn, why do they give out?

They are weakened mechanically by
the expansion and contraction due to the
enormous rise of temperature when
lighted and the corresponding drop when
the current is cut off. There is also a
slow reduction in the thickness of the
filament due to minute particles becoming
detached from the surface and deposited
on the inner surface of the glass bulb
by a sort of electrostatic action.

1 154. What determines the choice be-
tween tantalum and tungsten lamps, be-
sides the efficiency?

Tantaluin lamps operate best on di-
rect-current circuits. The filaments are
better adapted than tungsten to withstand
vibrations and shocks because they are
not so thin or so fragile. Tungsten lamps
operate equally well on direct-current and
alternating-current circuits and give a
more nearly pure white light than tanta-
lum.

I l.S.S. For what voltages are the usual
Ivpes of incandescent lamps made?

Lamps used for ordinar\' illumination
arc made for voltages ranging from 27
to 125 volts, but those most used arc
for 100 to 125 volt« hccauKc that is the
stnndnrd ranee of lighliiig circuits.

POWER

November 7. 191 1

Generatiiif^ Plants at Wc-
toria Falls

The Victoria Falls & Transvaal Power
Company, according to the Daily Con.-
sular and Trade Reports, has three gen-
erating stations in South Africa, the old
one at Brakpan and two new ones at
Rosherville and Simmer Pan. while the
foundations for the station at Vereenig-
ing are now being proceeded with.

The Simmer Pan plant comprises six
impulse turbines of 4500 brake horse-
power each. The generation is three-
phase, 50 cycles at 5000 volts transformed
to 10,000, 20,000 and 40,000 volts, as
required. The whole system is managed
from the control room, which is in charge
of an engineer in telephonic communica-
tion with every part of the system.

The actual cost of generation is not
known, but at the station of the Rand-
fontein Central, where coal costs more
in consequence of 25 miles extra haul-
age, the cost has been Drought down to
below ' _. cent per unit at the switchboard
and to 0.8 of one cent into motors all
over the property. When the central mill
is in full operation and the amount gen-
erated increased, with consequent spread-
ing of the standing charges, it is con-
fidently expected that these figures will
be improved upon.

The stations of the Victoria Falls Com-
pany are being worked to their fullest
capacity, the Rand mines requiring con-
siderably more po.wer than they originally
contracted to purchase. At some mines,
consequent upon the scarcity of hammer
hoys, the old steam plants have lately
been started up to supplement the supply
of electricity and compressed air in bulk.

Powerful European Electric
Locomotive

A German technical journal reports
that the Maschinenfabrik Oerlikon has
just turned out an electric locomotive of
unusual size and character. It is an al-
ternating-current locomotive of 2000
horsepower, 13,000-kilogram tractive ef-
fort, and utilizes current at a pressure
of 15,000 volts and a frequency 13 to 17
cycles. The machine is thus larger than
that built last year by the Allgemeine
Elektricitiits Gesellschaft for the same
line; than that built for the Simplon tun-
nel by Brown, Boveri & Co.; than that
built two years ago for the Pennsylvania
Railroad, and also than the freight loco-
motive built for the Italian state railways.
It is to be run on the Spiez-Liitschberg-
Simplon line. It is from the designs of
the engineer, Thormann, and is described
by our contemporary as the first demon-
stration that with single-phase alternat-
ing current the highest requirements of
existing and projected lines can be sat-

isfied without exceeding the Continental
standards with regard to axle pressure. —
Railway and Engineering Review.

LETTERS

The Right Motor for the
Job

1 was very much interested in reading
the article on selecting the right motor
for the job, by Mr. Williston in the
October 3 issue, but I do not see why;
with the conditions outlined, he did not
use the chain drive and motor operating
at 1800 revolutions per minute. We have
a number of drives of this capacity ap-
plied to motors running at 1800 revolu-
tions per minute with ratios as high as
5 to 1 and with the center distances
varying between 18 inches and 3 feet.
Under the conditions as outlined there is
no reason why the drive should not be
installed with center distances of ap-
proximately 18 inches with a total cost
of $96 for the motor and the drive,
thereby saving S12 over the cost of the
equipment he used and obtaining a higher
drive efficiency as well as higher motor
efficiency. It is doubtful if a good belt
arive can be secured with the 1200-
revolution motor to a 500-revolution
shaft with 6-foot center distances. We
have found that it is inadvisable to use
center distances less than 8 feet with
ratios of 2 to 1. and 10 feet on ratios of
3 to 1, unless the belts be crossed, as
the belt speed and the standard sizes
of the pulleys sold with the motors do
not allow the best efficiency of drive,
requiring altogether too tight belts and,
therefore, comparatively short-life belts,
besides being hard on both the motor
and the shaft bearings.

I do not agree with Mr. Williston that
the standard diameter of pulley on the
motor as furnished by the manufacturer
should be selected. My experience has
been that the regular motor pulleys are
too small, giving an average belt speed
of 1200 to 1500 feet per minute. The best
results as regards economy of operation
and first cost are secured by using the
highest practical belt speed, up to the
point where centrifugal force tends to
reduce the adhesion between belt and
pulley. This in most cases is between
5000 and 6000 feet per minute. By the
use of high speeds the size of the belt
can be materially reduced, as can also
the face width of the pulleys, thereby
reducing the first cost and at the same
time, owing to the reduction in the re-
quired belt tension, reducing the main-
tenance cost.

In all belt drives it is advisable to
make a very careful study of the area of
surface available on the smaller pulley,
as this is the limiting feature in most
cases. If conditions are such that small
pulleys are absolutely necessarj', the

surface contact can be readily increased
through the use of special pulleys, such
as those with leather faces or cork in-
serts, but these conditions are usually
special and should be avoided if pos-
sible. The cork-insert pulley is working
out nicely, however, and can be relied
upon to transmit a very much greater
amount of power per unit of surface.
Long center distances are usually neces-
sary, particularly with large ratios, in
order to reduce the tension on both tight
and loose sides of the belts, and increase
the arc of contact on the driving pulley.
Henry D. Jackson.
Boston. Mass.

Rope Drive v.s. Electricit}' for
Textile Mills

1 quite agree with W. H. Booth in his
statements regarding textile mills with
reference to the relative advantage of
electric and the modern rope drive.* So
far as we have been able to determine,
in a new plant under conditions of op-
eration as originally installed, the rope
drive is slightly superior to the electric.
There is, however, always to be con-
sidered the possibility of expansion, and
it is doubtful if. under the conditions of
expansion, the rope drive can be so
readily adapted to the needs of the en-
larged mill as can the electric, with the
lesult that while originally the rope drive
was superior to the electric, finally the
rope drive would be very much more
costly in operation than the electric.
Therefore, it is well to figure carefully
what the possibilities are of expansion,
and in case rope drive is installed, any
future expansion, instead of being an ad-
dition to the original mill, should be a
complete new mill, thereby retaining all
of the advantages of the rope drive and
none of the disadvantages of attempting
to extend the original drive.

With the electric drive, however, no
such difficulty exists. The plant can be
jnstalled for an economical drive elec-
trically in the first place, and necessary
space left for additional units in the
power plant, and any additional ap-
paratus installed in the mill can readily
be driven by electric motors at good
efficiency, no matter where the addition
may come, the only requirement being
the installation of the motors and the
running of the necessary wires.

As Mr. Booth states, it is impossible
to make any hard and fast rules as to
what to use or not to use. but each par-
ticular plant must be worked out on its
own basis. It is manifestly unfair both
to the engineer and to the owner to make
comparisons between plants of totally
tmlike character.

Henry D. Jackson.

Boston, Alass.

Octo-

November

POWER

%^'^f CI c?

.,v.

"^^-'

•-.i 1

ir " ' :"■

:z-~'^'i "'" ~ ;

The Rayner Two Stroke
Engine

Since the adoption of the Knight
sleeve-valve gasolene engine by the
Daimler and Panhard companies for au-
tomobile equipment, there has been sud-
den activity on the part of engine build-
ers, designers and would-be designers,
with the obiect of producing a sleeve-
valve engine that will be a satisfactory
substitute for Knight's without infringing
his patents.

One of the latest of these efforts is
illustrated by the accompanying engrav-
ings, which give largely diagrammatic

Referring to the drawings, the power
piston P works within the sleeve exten-
sion S of the pump piston p. and is pro-
vided with the usual packing rings. The
sleeve S is attached to the trunk T of
the pump piston and the trunk slides in

representations of the construction in-
volved. The engine is really not a sleeve-
valve machine in the usual sense of that
term. It is provided with two concentric
pistons, one of which delivers power to
the crank shaft and the other pumps in
the charge. Both of them ovcrnJn ports
and thereby serve as valves in exactly
the same way as does the piston of a
three-poii engine workinu on the two-
stroke cycle. This does not mean, how-
ever, that the Rayner engine, here de-
scribed, is merely the equivalent of an
ordinar>- two-stroke engine.

Fic. 2.

the cylinder bore like an ordinal^' tmink
piston and is provided with packing rings
near the upper end. The trunk T sc(%'es
as an exhaust valve, covering and un-
covering the ports E, and the main pis-
ton P serves as an inlet valve cooperat-
ing with the inlet pons / in the wall of
the sleeve .S. This sleeve works in a
guide 0 which is attached to the outer
cylinder wall by a circular flange P.
thereby forming a closed chamber C in
which the pump piston p operates.

The sleeve S and, consequently, the
piston p are reciprocated by means of an

auxiliars' crank and connecting rod, as
indicated clearly in Fig. 1 ; the stroke of
the sleeve is one-half that of the main
piston P and the relative motion of their
contiguous surfaces therefore occurs
at one-half the rate of the piston
speed.

Fig. 1 shows the sleeve S at the bottom
of its travel, with the exhaust ports E
entirely uncovered. The inlet ports /,
however, are not yet uncovered because
the small crank is set slightly ahead of
the main crank, as shown in Fig. 2, and
the piston has not yet reached the .end
of its downward stroke. When it does
so. a little later, the inlet ports are un-
covered, as shown in Fig. 2. and the
fresh charge, which was compressed in
the chamber C by the piston p on its
downward stroke, expands into the cylin-
der, as indicated by the arrows. Its
direction being upward, it assists the
escape of the burned gases from the
interior of the sleeve S. On account of
the lead of the short crank, the exhaust
ports are covered before the inlet ports,
as represented in Fig. 3, and there is an
appreciable period during which the
charge expands into the cylinder after
the e.xhaust ports have been closed.

The continued upward motion of the
piston within the sleeve closes the inlet
ports and compresses the charge in the
cylinder in the usual way. The simul-
taneous upward travel of the piston p
draws another charge into the chamber
C through a check valve (not shown),
ready to be compressed on the next down-
ward stroke.

It is evident from the foregoing that
the engine operates on the two-stroke
cycle, the exhaust and inlet ports being
uncovered at the end of each downward
stroke. The operation differs from that
of the ordinary two-stroke engine, how-
ever, in that the inlet ports are open a
much longer lime, because of the slight-
ly differential travel of the sleeve S and
the piston P during that part of the
cycle; for the same reason, the exhaust
ports arc opened and closed appreciably
ahead of the opening and closing of the
inlet ports, and they remain open twice
as long as in the ordinary engine he-
cause the sleeve .S travels at one-half
the speed of the piston.

We understand that the engine has not
been built, and therefore no definite
information regardine its performance is
available The drawings were supplied
by Arthur .1. Herschmann. of Watchung,
N. J., who rcprcscnis the inventor in this
country.

POWER

November 7, 191 1

Chart for Reducing G-as Vol-
umes to Standard Conditions

By J. Ai.BKRT M. Robinson

In order to do away with the tedious
work of reducing gas volumes to standard
conditions, the accompanying chart was
calculated and plotted. Each diagonal
line shows the variation of volume with
pressure for a certain constant tempera-
ture. The range of the chart is from 32
to 100 degrees and from 27 to 32 inches
mercury pressure. It is calculated on
the basis of standard conditions of 29.92
inches of mercury and 62 degrees Fah-
renheit. The equation is

29.92 T~
where

p„i T= Absolute pressure observed, in
inches of mercury;
T = Absolute temperature observed
(Fahrenheit temperature -
460);
V = Volume under standard condi-
tions corresponding to one
cubic foot under the observed
conditions.

E.XAMPLK

In the wet-test meter of a gas calorim-
eter the temperature is 72 degrees and
the pressure is 1 inch water; barometer,
29.69 inches. The low heat value of the

then trace straight downward, as indicated
by the dotted line, to the scale of vol-
umes, where the value 0.976 is obtained,
fhis means that one cubic foot as metered
is equal to 0.970 cubic foot under stand-
ard conditions. Therefore, the low heat
value under standard conditions is
122. 1

B.t.u. per cubic foot.

The chart may also be used in the
reverse direction. Suppose it is desired
to find what pressure would be neces-
sary at a temperature of 32 degrees in
order that the volume should be the same
as under standard conditions. Trace up-
ward along the vertical line starting at
1 cubic foot until the 32-degree line is
reached; then trace the horizontal line at
the intersection until the pressure scale
is reached; the figure there is 28.2 inches,
which is the desired mercury pressure.
Conversely, the temperature can be found
if the pressure is known.

CORRESPONDENCE

Trouble from Long Exhaii.st
Pipe

Mr. Delbert's account, in the August
22 issue, of the failure of an engine to
start through excessive length of the
exhaust pipe, recalls an experience I had

Standard 6qs Volume, CublcPeet
Pressure-volume Chart for Gas

gas as metered is 122.1 B.t.u. Required,
the low heat value under standard condi-
tions. One inch of water equals 0.07
inch of mercury; therefore the observed
pressure is

29.69 -f 0.07 = 29.76
Inches of mercury.

From 29.76 on the side scale of the
chart, trace horizontally to the right until
the diagonal line of 72 degrees is reached;

a few months ago. In my case also the
trouble was caused by a straight-run ex-
haust pipe. It was not practicable to
shorten this in the manner indicated by
Mr. Delbert, but the difficulty was over-
come by substituting a 4-inch pipe for
the original 2' '.-inch pipe.

The speed of the engine was fairly
high and the excessive pressure in the
long exhaust pipe had no time to dis-

seminate before the next exhaust. Hence,
the pressure at the end of the exhaust
stroke and at the beginning of the suc-
tion stroke was considerable, and in-
stead of fresh gas being sucked in when
the inlet valve opened, the waste gases in
the cylinder blew back through the inlet
and air ports and prevented the admis-
sion of a fresh charge. The reduction
of pressure at the end of the exhaust
stroke, after the larger pipe was fitted,
was accomplished as had been expected,
and the trouble ceased.

Indicator diagrams taken with a light
spring gave the clue to the cause of the
trouble; the exhaust lines of these re-
sembled that shown in the illustration,
the pressure rising at the end of the ex-
haust stroke, presumably as the exhaust
gases going up the pipe caught up with
the previous exhaust charge.

JoH.N S. Leese.

.Manchester, Eng.

Mr. Caton's Die.sel Engine
Diagram

Tfie Diesel-engine diagram submitted
ty Mr. Caton in the issue of October 31
is subject to at least one criticism: the
power developed by the engine, accord-
ing to the diagram, was less than the
power delivered by the generator driven
b\- the engine. With 60 pounds mean
effective pressure and 164 revolutions
per minute, a 16x24 cylinder would de-
velop

60 X 2 X 201 X 82

■ = 60

Diagram from Diesel Engine

indicated horsepower. .-\s there were six
cylinders, the total indicated horsepower
would be 360. If the generator delivered
275 kilowatts, that is, equivalent to

1.34 X 275 = 368 J. <
electrical horsepower, or 8',' horsepower
more than that indicated in the engine
cylinder. There is evidently something
wrong somewhere. The output of the
generator should, of course, be less.

.Another feature of the diagram that
seems to be wrong is the pressure during
the exhaust stroke. This was below at- .
mospheric pressure, according to the dia-
gram.

Geo. W. Malcol.m.

Brooklyn, N. Y.

''They make engine wheels out of paper
now."

"That so? Use 'em for stationei^' en-
gines, I s'pose." — Cleveland Leader.

November 7, 1911

POWER

Repaired Economizer Mani-
fold

A manifold of a fuel economizer
cracked just around the fillet to the
flange.

The manifold was removed and fas-

HO\X- THE PaCKINO IS APPLIED

tened in a lathe and the inside smoothed
up as far as the branch. It was then
threaded, and a nipple screwed in place.
The nipple can be painted with either
red lead or smooth-on.

H. K. Blessing.
Philadelphia. Penna.

Tail Rod Stuffing Box

The accompanying illustration shows
the arrangement of a rear-end stufRng
box which an engineer placed on a high-
speed piston-valve engine. The rear tail

Stiipfinc Bok for Valve-stem Tail Ron

rod A is held in place by a stuffing box,
and holds the valve in a central posi-
tion; it also reduces the wear on the
bottom of the seat.

The engineer claims that there has
been less leakage past the valve since

the change was made and that the valve
will last longer because of it.

C. R. McCahey.
Baltimore. Md.

Grooved the Funnel

Tn prevent tanks, etc., from becoming

air bound when filling through a common

funnel. I hammered a groove in the side,

as shown in the sketch; the groove should

Section A-A

Grooved Fi;nnel

be wide and deep enough to prevent its
being sealed by the liquid.

P. P. Fenaun.

Lynn. Mass.

Accurate Indicator Connection
Numerous attempts have been made lo
obtain accurate connections between the
engine piston and the indicator driver.
Cords cannot serve, nor will chains, as
both stretch and a true registry is de-
feated.

About 4.'> years ago I discovered a
means of absolute accuracy for making

this connection and those who desire ac-
curacy can use the old design.

On the end of the crosshead a cut
rack was secured to move with the pis-
tcn. The rack operated on a gear
wheel whose axle carried a smaller gear
wheel that meshed with a toothed bar
which was long enough to operate on
one or two geared drums as desired. The
rack there gives a perfect registry with
every stroke.

Petkr Van Brock.

Jefferson, Iowa.

Emergency Die Stock

One way to use a solid pipe or holt
die where no die stock is available is to
take two pieces of oak and two '^-inch

Wooden Die Stock

bolts, and use as shown in the illustra-
tion.

J. .1. O'Brien.
Buffalo. N. Y.

A Twenty Four Hour Log

The accompanying data are from my
daily record. I would like to have the
expression of engineers as to the eco-
nomical operation of the plant.

The plant has a 500-kilowatt turbine
which operates with a very small load.
The plant, however, has a fair live-steam
load. The record for one day's run of
24 hours' duration is given herewith.

-Ill Ki

274 d<«r(vg

Avinmi- kiloHiiiis

Aviratrc wuliT ti'in|MTiiliin- wX

• ■rotHmii7.fr
A VI rate walcr ti'mtwraliin' al

l»»il<T<
AviT»e<- woliT iciniKTulim' »l

hoi weir ondpgTws

|..i;il «;il. r . \a|ioral.-.l. .. .1S2.M0O poiinil-

I ;|4..H(H) iHiiind-'

;(.in4 imnnil"

r poiiiHl "f coal 1 1 pounil-i

rlioiir. 1 ,4.-.0 imiincj!.

.„.r Imiii l.'i.ll.'iO poiiniU

oiitx. III! IndiiiL-
,„l „,| sun :iii

iN.iiii'l- "I "■«' |MT "umin' tiM'i
nf irmtf •iirtnr.- iht tiniir 1 H |«iin<l»

The plant contains two boilers of 275
horsepower each.

C. R. Ward.
Walerford. N, Y.

POWER

November 7. 191 1

Float Pump C'lMitrol

1 have had considerable experience
with float rigs for governing steam
pumps, and have found that the arrange-
ment shown in the inclosed sketch works
very well. The float is placed in a sep-
arate chamber and connected to the main
tank with small pipes after the manner
of a water coluinn. The float is made of
heavy material and the weight is bal-
anced by a proper counterweight on the
other end of the beams. In cases where

Design of Pump Control

the weight on the beam center bearing
is so great that the float is not sensitive,
the trouble is easily remedied by making
the beam center bearing 'i inch larger
than the journal and then filling the
space all around with pieces of 'i-inch
drill rod. thus making a simple and ef-
fective roller bearing.

The beam center bearing was bolted
to the bracket in order to facilitate lin-
ing; the gear must be accurately in line
if it is to work at all.

C. S. RUNION.

New London. Conn.

Removiiii;^ Piston Rods

There are numerous ways of remov-
ing a keyed piston rod from the cross-
head. In one plant of which I was chief
it was necessary to disconnect the piston
rod from the crosshead of one engine
several times, the jack shown in Fig. 1
being used to draw the rod out of its
seat.

The side pieces were hooked back of
the crosshead and the screw which pushed
ifgainst the rod was turned with a pipe
wrench. This worked well but necessi-

tated removing the crosshead pin, which I
did not wish to do. While the key was
nut 1 took exact dimensions for a set
of gibs and key to fit the slot in the
crosshead and rod with which to draw the
rod without removing the pin. Thpy were
made as shown in Fig. 2.

up suddenly compresses the springs,
thereby causing the spider and shaft to
start slowly.

The key in this case was ".s inch thick,
3H inches wide at the top and 3^-^
inches at the bottom. The wedges and
gibs were made so that when they were
in place they would be the exact taper of
the key in the gib A, the shoulders of

"7 '(C:>

Fig. 2. Wedge and Gib Arrangement

which bore against the crosshead, and the
part B was cut out 's inch at both ends,
as shown. The center part bore against
the bottom of the slot in the rod, but
the parts C C clear the crosshead. The
v.edge and gibs are given a draw of "i
inch to the foot.

It only requires a few blows with the
sledge to loosen the rod. The advantage
of this method is that the crosshead pin
does not have to be removed when re-
moving the piston rod. The gibs and
key are made of machinery steel and
were finished upon the shaper.

J. C. Hawkins.

Hyattsville. Md.

Spring Drive

In order to reduce the shock to a
machine when suddenly started, a spring
drive will be found of benefit.

The accompanying illustration shows a
motor with a pinion A secured to the
armature shaft. This pinion is geared
to a large gear B which runs loose on
the shaft D. The spider C is secured to
the same shaft by setscrews.

As the current is turned on, the gear B
revolves and trarfsmits its power to the
spider C by means of springs E, F, G and
H. These springs are held in position
by lugs, cast on the arms of both the
gear and the spider. The gear starting

A Spring Drive

This method of reducing the shock vrill
prevent trouble and increase the efficiency
of the machine to which it is applied.
G. B. Tanis.

Paterson. N. J.

Oil Cup \'ent Guard

The ordinary glass-sight oil cup has
a slide on top to permit filling and the
slide has a hole for a vent. To pre-
vent dirt and grit working in through the
vent hole, bend a piece of smaH copper
tube having a 1/16-inch hole into U-

.AiR Vent in Gl'ard

shape and solder it to the slide with the
hole in the U-tube over the vent in the
slide. This will gwe the necessarj' vent
and the dirt and grit falling on the eiler
can be wiped off — not in.

Charles H. Franklin.
Schenectady. N. Y.

POWER

707

Adjusting Nut Lock

In cases where the studs in the crank-
pin strap are used for tightening the
brasses, the scheme illustrated herewith
is good.

It is often difficult to tighten the jamb
nuts enough without disturbing the ad-

^ ffl

(2) m

Tx;

Lock-nut Keeper

justing nuts. A yoke is made from a
piece of sheet iron and placed between
the nuts as shown. The lock nuts may
then be drawn as tightly as desired with-
out even putting a wrench on the bottom
nuts to hold them in place.

Edviard T. Binns.
Philadelphia. Penn.

Replacing Crank Pins

.A method employed quite extensivelr
in putting in new crank pins, especially
in the larger types of engines and when
gas is available for heating purposes, is

Heating Device

herewith described. Thv old pin is re-
moved by chipping off the bead on the
back end of the pin and driving out with
a heavy sledge. After reboring the pin-
hole with a portable boring bar, a new
crank pin of proper size is made. The
usual allowance in present practice for
a shrink or press fit for crank pins of
from 8 to \h inches in diameter is from
0.007 to 0.012 inch, and it would requir."
approximately 45 to 12.^ tons pressure
to force them in place if they were put
in with a hydraulic press as is the usual
practice in most shops.

As in most cases it would be too ex-
pensive 10 rig a portable press even if
one were at hand to pu*. in a new crank
in the field, most new pins are put in
by heating the disk to expand the hole
enough to allow the new pin to be put
in place and the disk to shrink on the
pin.

A method used quite extensively and
successfully for heating the disk is
shown in the cut. A ring is made of '_•-
inch iron pipe and bent to form a ring
6 inches larger than the diameter of the
crank disk. Small A. -inch holes are
milled around the inside diameter of the
ring to allow the gas flames to be di-
rected onto the disk. A gas pipe or hose
is connected at A. The gas burner shown
at B is made from a short piece of I'l-
or 2-inch pipe, a pipe coupling cap and
bushing and is drilled full of i'„-inch
holes. It is used by inserting it into the
crank-pin hole, a gas connection being
made at C. It is best to let the gas ring
outside of the disk burn two or three
hours before applying the burner to the
crank-pin hole. This allows the disk and
counterbalance to become heated up all
around, and eliminates the danger of
cracking the disk, which would be liable
to occur if heat were applied locally to
the crank-pin hole.

When it is necessary to put on a new
crank disk in the field it is good practice
to use the crank-pin hole in picking up
the disk, and when the disk is in place
put in the crank pin, the same heat an-
swering for both operations.

E. P. Bal.m.

Pittsburg, Penn.

'rrc)uhlt^,st)nie Back Pressure
\'alve

Several years ago 1 experienced con-
siderable trouble with a back-pressure
valve that would pound on its seat every

Iv.pRr.vrn Back-prkssiirf. Vaivf

time it was opened to the atmosphere,
although it was fitted with a dashpnt and
bypass. It was so designed that when
the stem A was screwed in the valve and

the dashpot piston would rise, it would
allow the condensed steam to flow down
through the bypass B. past the valve C
and up into the chamber D, thereby
forming a cushion for the piston £ and
thus preventing the valve F from pound-
ing. Although this arrangement looked
all right, it did not work satisfactorily.

I proceeded to alter the valve in the
following manner: The drip valve G was
removed and a hole drilled through it
and threaded at the lower end for a
packing nut H. I then drilled and tapped
one side to receive the setscrew X.

I then replaced the drip valve in its
former position, and passed the stem J
up through it until it touched the bottom
of the piston E. as indicated by the
accompanying sketch. The setscrew X
was screwed in the side of the drip valve
as shown.

All that was necessary to do now was
to slack off on the stem A, push up the
stem J with one hand, and at the same
time tighten up on the setscrew X, with
the other hand. This kept the valve from
off its seat and there was no further
trouble from pounding.

George J. Little.

Passaic. N. J.

Concrete I'ipe joitit

When about to make some repairs to
a headgate it was found that the job
could iiot be done without shutting down
the plant, on account of no condensing
water. I decided to build a small dam

, . . Pv

I

' I

Pipe Joint Made of Concrete

upstream and lay a 6-inch pipe down to
the condenser intake. 1 had 45 feet of
pipe, but there was one long piece with-
out threads on one end and no way at
hand to cut them.

A nail keg with the heads knocked out
was slipped over the pipe after cutting
a 2x3-inch hole in one side of the keg. A
second pipe was butted against the first
one and a piece of burlap 6 inches wide
that had been snaked in cement was
wound twice around the joint. The keg
was then placed over the joint, the ends
filled with burlap and cement mortar
poured into the hole until the keg was
full.

Ai MfiN Skinner.

Chadwicks. N V

POWER

November 7, 1911

Split the Stuffing Box Gland

Some time ago I was an engineer in
a plant where a breal^down occurred on
one of the low-pressure pistons of a
compound enRlne.

Before making the necessary repairs
1 was ordered lo prepare the packing. I

Split Stutfinc-box Gland

found that the men had forgotten to put
the gland of the low-pressure cylinder
on the piston rod when assembling the
engine. I suggested sawing the gland
through the bolt holes, as shown in the
sketch.

Two small brass liners were placed
between the halves of the gland in the
cut. The engine was soon running and
the gland gave no trouble; in fact, no
changes were made for over two years.
T. D. Parfett.

Claridge, Penn.

Governor Gave Faulty
Regulation

According to the old settlers on the
job, the diagrams shown herewith were
the best that could be obtained from a
14 and 26 by 30-inch Corliss engine of
the nonreleasing-gear type. It ran at a
speed of 150 revolutions per minute and
was governed by an automatic governor.

They said that the builder's experts
had given up trying to improve the run-
ning qualities of the engine which had
been hammering away for years.

The governor was pounding at an
alarming rate and it was found that the

Diagrams Showing Faulty Valve
Setting

oil gag pot was inoperative; the piston
in it was perforated with four ;4-'nch
holes.

These free oil passages permitted a
too free movement of the governor which
caused the gag-pot piston rod to wear.

The four holes in the piston were
tapped and plugged, with the exception
tliat a quarter section was cut out of
one of the plugs. A new rod was also

provided. These were the essential al-
terations, but they made the governor
stiff and yet sufficiently sensitive to give
close regulation.

When a governor requires so much
resistance against vibration, the logical
conclusion is that it is out of balance.
Although it may be nearly balanced in
respect to centrifugal force of the entire
mass of the wheel, it is out of balance
in relation to gravitation acting upon the
articulate parts.

The phenomenon presents a weight
rising against gravitation, and with a
spring in which a force is stored until
the weight descends, when the force
stored in the spring acts with the gravity
of the weight, thus striking a blow.
V. J. Ironside.

Boston, Mass.

Prevented Packing Blowing
Out

A simplex pump, after several years'
service underground, had become warped
in the planed joints, and on being over-
hauled in the shops the joint between
the steam chest and the cylinder was
overlooked. When steam was turned on,
the gasket would blow out at the ends.
By using different combinations of
double gaskets, lead strips and wooden
wedges, it could be made to hold for an

Pu.MP As Repaired

hour or two, but not long enough to keep
the water out of the mine.

Existing conditions made it impossible
to get another pump, so I devised the
scheme shown in the illustration.

After making the Hax-'^s-inch iron
cross bars B of suitable lengths, they
were flattened on the ends and drilled for
'.-inch side rods to form a clamp C. I
put in a new gasket and a narrow strip
of red rubber doubled, across each end
as shown at A. Over these rubber strips
were placed the bars B, which were drawn
up as tightly as possible by the side rods.

The pump ran in this manner without
trouble for 10 months.

W. E. Bertrand.

Philadelphia. Penn.

Babbitt in Crank Pin Box

About a year ago I was sent to a
mill where the engineer was having
trouble with the engine crank pin. I
scraped the brasses and polished the pin,
but it continued to heat. I then turned
the brasses larger and babbitted them,
and the trouble was over.

The governor also ran hot, which
caused the engine to race and run un-

Brass Washer Caused Trouble

steadily. The governor w-as fitted with a
brass liner, as shown at A in the illustra-
tion. It was removed and a cast-iron
liner substituted and there was no more
trouble.

A. L. JOHNSO.N.

Somers. Mont.

Burning Fuel Oil
Can any reader of Power give me an
approved plan for a horizontal tubular-
boiler furnace in which fuel oil is to be
burned?

In most of the plants I have seen, the
oil is burned with the aid of steam, the
atomizer extending horizontally through
the front of the boiler setting and in the
direction of the draft.

I have been told to let the flame im-
pinge against the bridgewall so that the
flame will be deflected toward the ash-
pit, the grates having been removed; see

Furnace for Burning Fuel Oil

illustration. Also, to burn the oil with
the ashpit door closed and the damper
opened a very little.

I would appreciate any information
relating to a reader's experience in burn-
ing oil, the quantity burned per kilo-
watt-hour in producing electrical en-
ergy.

D. A. Steiner.

Frankfort. Kan.

November 7, 191 1

P O \V E R

709

Engine Runs with Steam
V'alves Closed

In the September 5 issue, page 371,
iMr. Lentz states that he has a 16x32-inch
Corliss engine which will run at slow
speed when both admission valves are
closed, and that after reboring the valve
seats, fitting new valves and setting them
with the aid of an indicator, the en-
gine runs faster with the admission
valves closed than it did before re-
boring.

He also states that he knows of a
20x36-inch engine of the same type
which does the same, although it has
only been running six months, and he
suggests that the valves are not correctly
set; he has tried the latter in all positions
with no better result.

Perhaps the following experience will
be interesting, as it is a very similar
case to his own. The plant consisted
of a 20 and 36 by 42-inch engine direct
coupled to a dynamo and two small
high-speed vertical engines, all running
condensing and with 140 pounds boiler
pressure. The first extension of this plant
consisted of one 300-horsepower and two
1000-horsepower vertical triple-expan-
sion condensing engines. As this neces-
sitated a correspondingly large extension
of boiler power, the steam pressure was
increased to 180 pounds to obtain better
economy. When the Corliss engine was
run at this pressure the trouble be-
gan.

The parts stood the increased pressure
fairly well, with the exception of the
trosshead shoe which gave a little trouble
through heating. The chief difficulty,
however, was that the engine would run
above speed when the entire load came
off, although the steam-admission valves
did not open as the governor was in its
highest position.

As the engine had been working some
time the valve seats had become worn.
They were rebored and new valves were
fitted, but with no improvement, for with
ISO pounds boiler pressure the engine
still ran above speed, although the ad-
mission valves did not open.

If was at once realized that this was a
question of valve leakage and that the
setting of the admission valves would
not affect it as they covered the ports
correctlv wh'^n at rest. The admission
valves were then fitted most carefully,
with but Slight improvement.

Then it was decided fo nin the engine
for a lime so that the valves could wear

Comment,
criticism, suggestions
und debate upon vsriouf,
artides.letters 3nd edit-
orials which have ap-
peared in previous
issues

tighter. When the vacuum was reduced
4 or 5 inches the engine would govern
all right. This was done by cutting down
the circulating water, but it needed too
much attention as the amount of water
used varied with the load and there was
also the risk of losing the water, the con-
denser being of the ejector type.

The boiler pressure was then reduced
to 140 pounds whenever this engine was
running; at this pressure the governing
was quite satisfactory and after a few
v.eeks the engine was tried again at the
higher pressure. It still speeded above
normal, although the steam-admission
valves were not operating; then the mak-
ers of the engine were called in.

They sent a man to see what was
wrong and in a week or two their expert
came. After a week's work he reported
that the engine was not designed for
180 pounds steam pressure and must be
worked at the lower pressure.

He stated that all condensing Corliss
engines could run with their steam-ad-
mission valves closed If the engine was
first started and the steam pressure was
moderately high.' He illustrated this by
taking out the governor spring, starting
tip the engine with 140 pounds boiler
pressure and showing the engine run-
ning with the governor In Its topmost
position and the admission valves
closed.

The report staled that two factors pre-
vented the higher pressure being used
in this engine: the high vacuum ob-
tained. 27 to 28 Inches, needed very
little steam to run the engine light as
the condensing plant was not driven from
the engine; the other was that the engine
was only run at 9f> revolutions per min-
ute Instead of its designed speed of ll.'>
revolutions. As a consequence, the steam
leakage was sufficient to make the en-
gine overrun, whereas had the engine
speed been II-"" revolutions the govern-
ing would have been satisfactory.

Obviously this i:eport left only two al-
ternatives, cither valves iust large enough
for the engine speed of 00 revolutions

per minute had to be fitted to reduce the
steam leakage or the boiler pressure had
to be reduced; the latter was adopted and
the engine still runs with a boiler pres-
sure of from 140 to 150 pounds per
square inch.

Lest it should be thought that only
Corliss engines are capable of being run
by the leakage past the admission valves
the following experience of a vertical
condensing engine fitted with drop valves
is given:

The engine was a 20 and 35 by 20-inch
fitted with double-beat drop valves
actuated by a positive valve gear and de-
signed to run at 230 revolutions per min-
ute; it was sold for direct coupling to
a dynamo at 150 revolutions and had
an independent condensing plant. At
the maker's works it was run noncon-
densing and the governor acted satisfac-
torily. When the engine was started up
it was found that the governor would not
hold the engine when it worked con-
densing, or when the speed was at about
150 revolutions the steam-admission
valves were not lifted from their seats
but the speed of the engine gradually
increased until the flywheel was endan-
gered.

Many days were spent In the endeavor
to make these valves tight. They were
ground In cold, and under steam. They
were also motor driven and made to ham-
mer on their seats in the hope that they
would wear steam tight; then the en-
gine was run noncondensing for a time,
tut the engine would still speed up, al-
though the admission valves were not
lifted from their seats.

It was then decided to put new steam-
admission valves In the high-pressure
cylinder of just sufficient size to run the
engine at 150 revolutions per minute.
After this was done the engine was run
and the governor then held the engine.
Thus It was seen that the difference be-
tween the leakage of the larger valves
and that of the smaller ones was suffi-
cient to make the engine speed up when
there was no load on and when exhaust-
ing Into a high vacuum.

Mr. Lentz will sec from this that his
make of engine is not alone in running
?lowly with the sleam-admisslon valves
closed, but It is seldom that there Is a
combination of high steam pressure, high
\acuum. large valves and a Ilght-ninning
engine to demonstrate this fact; there-
fore it is not commonly known.

Jamrs Cannel!..

Stanford Ic Hope. Kngland.

710

P O W E R

November 7, 191 1

Show versus Efficiency

An editorial "filler" in the September
26 number, page 490, concerning the en-
gineer who polished his brass work with
asphaltum ought to be taken to heart in
more than one plant. Too often this
showiness in the engine room covers a
multitude of sins.

Neatness and cleanliness are virtues
to be insisted upon in any plant be-
cause clean machinery runs better and
because inspection and repairs are facili-
tated. But cleanliness is just as im-
portant downstairs around the filters,
condensers and pumps as it is in the
engine room.

The engineer naturally likes to receive
compliments upon the good looks of his
plant, so he proceeds to add polished
v\ork to dazzle tlie eye and draw out
more compliments. This is not neces-
sarily a bad thing; but there is always
danger that the care of this show work
will take time and attention away from
the main purpose of the plant, the eco-
nomical generation of power.

If one looks around in one of these
"show places" he will perhaps find a
big steam header drained into a well in
the rear and all of the water and heat
being thrown away. If not this, some-
thing equally as bad.

In a State institution some years ago
a new power plant was installed. A
double system of feed piping for the
three boilers was all of polished brass,
not even a valve or fitting being painted.
Nickeled steam gages were returned and
brass ones demanded. Everything pos-
sible was of brass, and the fireman was
to polish every bit of it every day. Two
of the best firemen they ever had left
at once on hearing this. One wonders
what sort of a CO, chart the plant would
show with the fireman putting in most
of his time rubbing brass. Efficient com-
bustion was evidently a very secondary
consideration in this chief's mind, for at
all costs things must look pretty.

There were some things that did not
look so nice. A 6-inch reducing valve
blew out its bonnet gasket and was left
in that condition six weeks, leaking
steam 24 hours a day. In the engine
room was a vertical separator with steam
going into the outlet and coming out at
the inlet; but how things did shine!

At another plant, one of the largest
of its kind in New England, an engi-
neer accidentally spilled a few drops of
cylinder oil on the floor. Now the snowy
whitness of that floor was an important
matter and a grease spot upon it did not
blend well with the polished turbines and
compressors, so the man was summarily
fired. But downstairs the "oiling system"
, would disgrace a backwoods sawmill.
The engines thump and pound, one fly-
wheel imitates the waddle of a duck;
but everything shines!

A power-station fireman was one day

obliged to paint two exhaust pipes run-
ning up the side of the engine room. The
next day the chief inquired of him why
the coal per kilowatt-hour had risen half
a pound above normal. "That," replied
the knight of the slice bar, "represents
what you saved yesterday by not hiring
a painter." He was right. It was im-
possible for him to fire carefully and at
the same time stand on a ladder and
paint.

Contrary to the evident belief of many
engineers, it is not the fireman who is al-
ways puttering at something who is
worth the most. Economical burning of
fuel demands constant and intelligent
attention. Do not distract the fireman;
do not think you must keep him on his
feet every minute.

The main purpose of a power plant is
the transformation of fuel into work in
the most efllcient manner possible. Then
if there is time to primp, go ahead.
While the tubes are covered with scale
and soot, while the settings are full of
cracks, while headers and drip lines and
blowoff pipes are leaking and the heater
is almost useless for need of a clean-
ing; while you are buying cold water
from the city and pouring hot water into
the sewer, no man about the plant can
be spared to make a show place of the
engine room.

William E. Di.xon.

Maiden, Mass.

Sand for Hot Boxes

Mr. Howarth's surprise and enlighten-
ment, as expressed in the issue of October
17, is only one of the many illustrations
of the value of Power as an educational
factor.

Like him, a great many of the younger
engineers have spent years at their work
without having become acquainted with
many of the common practices of older
and more experienced men, among which
was the use of sand for cooling hot
boxes. If any chief on an ocean liner
or of any other power plant objects to
the intelligent use of sand in an emer-
gency it is because he. like many others,
is lacking in knowledge and experience.

I first saw sand used on the S.S.
"Roanoke." of the Old Dominion line.
The aft journal of the low-pressure en-
gine had given trouble for some time
and one day it began to smoke. Water
was turned on and the engine slowed
down. The chief called for the sand box.
When it came the water was shut off,
and with one hand he poured a small
stream of oil into the box and with the
other fed in sand.

The smoke ceased almost at once. In
a few minutes the order for full speed
was given and the 16-inch journal soon
cooled to the normal temperature.

Since then I have often used sand for
cases of undue heating in both new and

old work, particularly on thrust bearings.

Sand is valuable to the engineer who
knows how to use it. It will not cause
a journal to heat if oil enough is used to
prevent the forming of a paste, but, on
the contrary, it will cool a bearing quicker
and better than any other remedy that I
have ever tried.

Engines are better built and installed
now than they were 40 or 50 years ago,
and many engineers pass years in ser-
vice without meeting with some of those
incidents which go to make up the sum
of a complete practical operating engi-
neer's experience.

W. G. Freer.

New York City.

Engine Knocks

In the October 3 issue, W. A. Mills
inquires about a knock apparently in the
low-pressure cylinder. If he will come
across with a few more data the quest-
tion could be answered more intelligibly.
Does the engine run condensing? How
much receiver pressure is carried? Is
there any end play to the valves? Is it
a Corliss, and what is its size? How
much compression is carried and what
kind of a diagram is produced ?

W. E. Cha,ndler.

Northbridge, Mass.

Lifting Water in Boilers

On page 528 of the October 3 issue,
C. G. Harden says in substance that, if
all the water in a boiler is of practically
the same temperature, he cannot account
for the circulation, for without tempera-
ture differences there can be no circula-
tion. Mr. Harden has a false idea of
the cause of boiler circulation and one
that is common among engineers.

The sluggish circulation in the hot-
water boiler connected to the kitchen
range, which is produced by tem-
perature differences, is certainly of a
very different character from that pro-
duced in a power boiler under full load;
the circulation is so strong in the latter
case that sheet-steel baffles or other steel
parts that may become detached are car-
ried along by the currents produced.

When first starting a boiler, the initial
circulation is due to changes in the
specific gravity of the contents, due to
temperature differences, as .Mr. Harden
assumes, but as soon as steam is formed
the changes in specific gravity become
very marked, and from an entirely dif-
ferent cause; namely, the production of
steam bubbles, whose weight is ver>'
much less than that of a similar volume of
water. The tendency is for the water to
flow from all points toward the one con-
taining the largest volume of steam
bubbles.

All of the water in a boiler under
operation is of practically the same tem-
perature unless the construction is such

November 7, 1911

P O >0C' E R

that pockets are formed away from the
paths of »he boiler circulation. This is
the case in the portion below the flues
in a Scotch boiler, unless especially pro-
vided with a circulating device.

If it weoe possible to operate a boiler
and maintain the temperature differences
of the water at various points, the same
as at starting up, the tendency to produce
circulation from this cause would be so
slight as compared to that produced by
the presence of steam bubbles that it
could not be considered a factor.

J. E. Terman.

Hartford, Conn.

In the October 3 issue, page 528, Mr.
Harden has replied to my letter published
in the September 12 issue, and 1 take
issue with him on some of his state-
ments. I -believe that more explosions
are due to improperly cutting in boilers
than to low water. But these explosions
are not due to the fact that the pres-
sure and temperature rise quickly when
the steam pressure is released; they are
due to water hammer. Of course, water
hammer causes a local rise in pressure
at some definite point on the boiler shell,
but this is due to the blow given by a
rapidly moving body of water and not
to any "rise in steam pressure."

Air. Harden says that my statement
that the temperature of the water in
boilers is practically constant is new to
him. This fact is not new to most engi-
neers. Professor Kent's "Steam Boiler
Economy" states that "by increasing the
rapidity of circulation in a steam boiler
we cannot vary the difference of tem-
perature, for the water and the steam in
the boiler are at about the same tem-
perature throughout. The circulation in
a boiler is due to a large number of
steam bubbles which are mixed with the
water. The specific gravity of the mix-
ture is lower in its upward than in its
downward movement, and this is what
causes the circulation in boilers and not
a difference in temperature.

In bolli of Mr. Harden's communica-
tions he has claimed that there is a rise
in steam pressure due to opening a valve
from a boiler into a header containing
a lower pressure than that in the boiler.
Il is improbable that there can be any
rise in steam pressure, as the steam space
in the boiler is connected with a header
of a low pressure. Therefore the steam
would flow from the high-pressure boiler
info the low header and prevent any ac-
cumulation of steam pressure. Further-
more, where are the heat and energy com-
ing from to "cause the temperature and
pressure to rise rapidly"'^

Mr. Harden has continually used the
expression "flashpoint" of wafer. This
is an exceedingly misused word in this
connection, for one would suppose that
if wafer were af the temperature corre-
sponding fo the steam pressure, if merely
needed a little shove to push the whole

mass of water into steam. But this is
not the case.

Boiler explosions have been caused by
opening the stop valve between the boiler
and header before the steam pressure in
the boiler was equal to that in the steam
header. In this case the higher pres-
sure from the steam main is admitted to
that in the boiler, but it is not this pres-
sure which causes the boiler to explode,
because the pressure in the main may be
lower than the normal working pressure
of the boiler and still cause an explosion.
The trouble is due to water hammer.

Since Mr. Harden wants some in-
formation on water hammer, I will add
the following: Water hammer has been
explained as follows: The steam dis-
charged into the boiler from the main
disturbs the surface of the water and
generates waves. The moment one of
these waves breaks so as to form a sort
of bubble and lose some of the steam,
the water-hammer action begins, because
the water in the boiler is at a lower tem-
perature than that of the steam (due to
lower pressure) and it follows that the
steam inclosed within the bubble will
condense, leaving a space there at a
lower pressure than in the steam drum.
The higher pressure acting upon the sur-
face of the water will then close the
bubble up almost instantaneously, and
the water forming the upper wall will
he brought down against the bottom with
great speed and violence.

The hammering action thus initiated
will increase the disturbance in the
water and larger and larger bubbles will
be formed in the same way, with the
production of increasingly violent shocks
when they collapse. Soon these waves
and shocks attain enough violence to
start a rivet and then the pressure within
the boiler does the rest. In fact, it is
always the normal boiler pressure which
does the most damage and it is only
necessary for some minor momentary
disturbance to start a rivet which th-;
normal pressure will pull apart and then
is had the entire range of pressure from
that of the boiler down to atmosphere
with a corresponding drop in tempera-
ture available for throwing the boiler
pieces around.

Some idea of this v ,»ter-hammer action
derived from blowing steam into a body
of colder water may be obtained by stick-
ing a hose into a barrel of water, and the
chattering and pounding which water-
hammer action will set up from a ''!-
inch opening will give some idea of what
would happen when a O-inch main is dis-
charging steam, although, of course, in
the latter case the conditions are not so
ideal as the steam would not he dis-
charged hclow the surface of the water
I'ntil it got the wafer surging about
violently enough to make its own steam
bubbles.

Frank J. McMahon.

New York City.

Steum Engine Lubrication

I read with interest the article by
R. D. Tomlinson on steam-engine lubri-
cation in the September 12 issue, page
396, of Power. It seems to me that the
oil companies should not only label their
oil barrels with the flash-and-fire test,
but they should also stamp on the head
of the barrel the temperature at which
the oil will properly atomize and mingle
with the steam. Then it would be a
very simple matter to choose the cylinder
oil best suited to the steam pressure
carried.

At one time I had charge of a tandem-
compound engine and I had considerable
lubrication trouble with it. I used the
very best cylinder oil that I could buy
but my trouble increased. Then I pur-
chased a cheaper oil and got splendid
results in the high-pressure cylinder, but
the low-pressure cylinder continued to
work badly. I then attached a plain
cylinder lubricator to the low-pressure
valve and my troubles were over. The
boiler pressure was 100 pounds per
square inch.

Charles Fenwick.

W.qpclla, Sask, Can.

Mr. Rockwell's Questions

Charles J. Mason's quotation from
Raibvay and Locomotive Engineering,
published in the October 3 issue, page
528, may be all right for locomotives,
but I believe it is entirely wrong as
regards stationary practice. While put-
ting cold water into a red-hot boiler may
not cause an explosion, it will do other
damage, especially in water-tube boilers.

About two months ago a water tender
in charge of a large battery of water-
tube boilers fell asleep and the water
dropped out of sight in the glass in No.
2 boiler. When he awoke he opened up
the feed valve and the result was that
14 front headers were cracked on a
line at the third row of tubes from the
bottom and the tubes were also burned
above this point, not below, which shows
just where the water was when the feed
was turned on.

I have seen several other cases sim-
ilar to this in wafer-tube boilers, which
leads me fo believe that water should not
be fumed into a boiler with low water
until it has been cooled down. Cold
wafer will not cause an explosion but
if will cause other serious trouble, which
in some cases might not extend beyond
leaking seams in a rcfnrn-fubular boiler,
but the sudden contr.ictinn may cause
the rivets fo be partly sheared and to
give way in an explosion .it some future
time. A much safer and s.Tncr way is
fo cool down the boiler before fuming
on the feed wafer.

J. C Hawkins.

Hvattsvillc, Md.

POWER

November 7. 191 1

Shaftintr Ca/ni/atto/is
If a line shaft is to transmit 100 horse-
power, how may the diameter be found ?
C. E. S.
For turned-iron line shafting a very
commonly used formula is

in which

d = Diameter of the shaft in inches;
R = Number of revolutions per min-
ute.
Assuming 300 revolutions per minute,

1^5

d -~ 3.44 inches.
The nearest commercial size is 3j',{
inches.

Htciun l^tscfwrged from Pipe to
Vessel

What horsepower of steam will be
discharged from a A4-inch pipe with 50
pounds at the delivery end discharging
into a vessel in which a pressure of 30
pounds is maintained ? The pressures
are gage; call them 65 and 45 absolute;
the end of the pipe is wide open.

J. O'D.

Dry saturated steam at 65 pounds pres-
sure has a temperature of 298 degrees
and contains 1172.9 heat units. At 44.67
pounds the temperature is 274. and the
heat content after adiabatic expansion
from the above condition is 1143.9 B.t.u.,
a difference of

1172.9 — 1143.9 = 29 B.t.u.
expended in acquiring velocity. Tliis is
equivalent to

29 X 778 = 22,562 foot-pounds.
The energy of a moving mass is ex-
pressed by the formula

2 (/
in which

£■ = Energy of the moving mass;

W z= Weight of the mass;

g = Force of gravity ;

r — Velocity of movement.
By transposition and substitution

2gE = v- where W = unity;

v- = 2 X 32.16 X 22,562;

v= 1 1,451,187.84;

v= 1204 feet per second.
The area of a M-inch pipe is 0.0037
square foot and the volume discharged
per second will be

1204 X 0.0037 = 4.45 cubic feet

Questions are^

not answered unless

accompanied by the^

name and address of the

inquirer. This page is

for you when stuck-

use it

or 16,020 cubic feet per hour. At 274
degrees the weight of steam is 0.1058
pound per cubic foot.
16,020 X 0.1058 = 1694.91 pounds per

hour
which at 30 pounds per horsepower per
hour would be

l694.qi

- = 50.29 liorsepouer

ii)-aphite as a Scate Preventive

Will graphite, used as a scale remover
or preventive, have any injurious effects
on a boiler?

C. B. S.

Several engineers have reported sat-
isfactory experiences with graphite as a
scale remover and preventive. There is
nothing in graphite which can be in-
jurious to the boiler itself. But in its
use care should be taken to prevent in-
jury from an accumulation of detached
scale on the heating surfaces.

Compressor Snction Pipe Covering

Is it necessary to cover the suction
pipe leading from a refrigerator to the
compressor?

J. B. C.

It is good practice as it tends to pre-
vent the absorption of heat by the con-
tents of the pipe and increasing the vol-
ume, thus reducing the capacity of the
compressor. Covering also tends to pre-
vent the drip of water which comes from
an uninsulated ice-covered pipe.

Ammo7iia Expansion Valves

Will one ^<;-inch expansion line and
cock- be sufficient for a brine tank con-
taining eleven l^-inch double coils 50
feet long?

L. A. O.
It will suffice if less than 100 feet
long, though for 1100 feet of I'^-inch
pipe two expansion valves would be
better.

Heat Va/ue of Lignites

In burning Dakota lignite I find a great
difference in the ash content. It is claimed
for one kind making about four times
as much ash and clinker as another that
its heat value is greater than that which
males but little ash. Can this be true?
L. R. D.

It is quite possible for a coal which is
higher in heat units or which will show
even less ash upon analysis to make
more ash or ashpit refuse in use. An
ash which has a low fusing point will
melt and run together in the furnace and
carry a lot of carbon with it, so that
the weight of stuff taken out as refuse
is not all ash, and may be greater in
quantity with a lower ash coal than it
would be with a coal having a higher
percentage of real ash which stayed in
a powdery form and could be sifted as
ash into the ashpit.

Burn a small sample of the coal thor-
oughly by itself, as in a porcelain dish,
completely to ash and find out in that
way what the percentage of real ash is
and how it compares with the ash in the
other. The heat value of the coal may
also be higher irrespective of its ash
content, depending upon its composition
otherwise.

Starti?ig Cross Compound Engine

How may an ordinary cross-compound
engine be started when the high-pressure
crank is on the center?

H. B. U.

By admitting steam to the low-pres-
sure cylinder. Such engines are usually
provided with means for admitting live-
steam to the receiver. When there is
nothing of this kind the throttle valve
may be opened slightly and the high-
pressure valve gear operated by hand, a
few strokes of which will pass enough
steam to the low-pressure side to start
it. If there is a vacuum in the con-
denser, the opening of one of the indi-
cator cocks will admit air enough to
start the piston.

B/ister on Boiler Sheet
What is meant when it Is said that a
boiler is blistered?

B. B S.
In the inanufacture of iron boiler plate
it sometimes happens that the layers are
not thoroughly welded and the heat of
the furnace causes thin, unwelded parts
to bulge outward from the plate in the
term of a blister, from which the name
is derived.

November 7. 191 1

POWER

713

Issued Weekly by the

Hill Publishing Company

John a. Hill, To*, aii.l Tivas. KoB'TMcKi£AN,Sec'y.

505 Pearl Street. New York.

122 Snulh Mlrhi;.-jiti Itoiilrvartl. Cbr<-aga.

6 Ikiuwrii' Slrwl, I>iii()an, E. C
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Correspondence suitable for the col-
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Name and address of correspondents
must be given — not necessarily for pub-
lication.

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Pay no money to solicitors or agents
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to the London Otiice. Price 21 Shil-
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Entered a.s second class matter. De-
cember 20, 1910, at the post office at
New York, .New York, under the -Act
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Business Telegraph Co<le.

Y,

CrSCVLATIOX STATEilEXT
Of thU iistic .30,000 copies are iirintfil.
A'one sent free regularly, no rctiirnx from
neics companicn, no back uumhers. FigiireK

\ilntl,

Contents

704
704

A Modem .Mine Powt-r Plant 688

Pulleys for High Spceil Bells 691

Firing Marine Boilera on the Chicago River. 692

A Problem in Statics 693

-uperheating and the .Superheater 694

Wrought Iron Castings 697

I ircproof Oil Storage House fi!i7

Power from Compressed .Air 6'.is

I Cylinder Oil Tested for .Actual ,Senicc fi9<.t

• atechism of Electricity 700

' :>'nerating Plants at Victoria FalU . 702

The Right Motor for the ,Iob 702

Rope Drive vs. Electricity for Textile .Mills . . 702

The Rayner Two Stroke Engine 70a

c tiart for Reducing Gas Volumes to Slamlard

Conditions 704

Trouble from Ijong Exhaust Pipe.
Mr. Caton's Dienel Engine Diagram
Practical Ivctters:

Repaired Economizer .ManUoid Tail
Rod Sturting Box. . . .tirooved thi' Fun-
nel Emergency Die .Stock . . A

Twenty Four Hour I>og. . . .Float Pump
Control. . . . Removing Piston Rodii. . . .
8pring Drive..,. Oil Cup Vent Giianl

Adjaiting Nut liock. . Replacing

Crank Pins. . . .Troublesome Back Prw-
Hure Valve. . . .Concn-te Pipe Joint .
.•<plit the SluMing Box Gland . . (iover-
nor Gave Faulty Regulation ... Pr<--
venl«| Packing Blowing Out ... Bab-
bitt in Crank Pin Box Burning Fuel

Oil 70.-.

liLxciuwion T«tteni:

Engine Runs with Steam Valve* Clo»od
. . . Show ver.<ui Ellici'ruy Sand for
Hot Boxes .... Engmc Knork.« Uft-

ing Water in Boilers. . > Steam Engine
I.iibricalinn .... Jlr. RockweH'a Quea-

tlon.« 70W-711

KililoriaL.. 71.1-714

Srho<il Heating 7),'i

r"< rft.rmnnre of thp Field Kn<7lne 7«1

V New Boiler Itatlni.- TJ2

708

Power Plant Records Nece.'^.sary

In many instances where a change has
been made from homemade power and
light to central-station service it has been
found, when too late, that instead of a
reduction in the cost of this service there
has been an increase of one hundred per
cent, or more.

It is somewhat difficult, if not quite
impossible, to apprehend the mental at-
titude of the business man who, whether
acting for himself or as the agent of
another, will make changes involving the
expenditure of thousands of dollars an-
nually without first engaging the service
of disinterested experts in the line in
which the expenditure is to be made.

If raw material is purchased for con-
sumption in any line of manufacture,
quality and price per unit of measure or
weight are among the specifications in
the contract, and the buyer gives intelli-
gent consideration to every paragraph in
the proposal he is asked to accept, going
at times to the length of employing chem-
ical or engineering advice before making
his decision.

But when it comes to the purchase of
heat, light and power the average busi-
ness man is all too often ready to accept
the unsupported statements of the cen-
tral-station solicitor without question.

There are badly designed, poorly
equipped and incompetently managed iso-
lated plants which cost the owner more to
operate than it would to buy the same
service from the central station. Such
plants, however, are the exception in-
stead of the average, and there are few
of the ver>' worst that cannot by the ap-
plication of power-plant common sense
be made to show results in the cost of
light and power that the central station
will hardly meet.

One of the items on which the solicitor
dwells at great length and with much
earnestness is the superiority of electric
transmission over shaft and belt where
power is used for machine driving. Its
superiority lies alone in the factor of
convenience, and the owner or user who
understands will not be deceived bv the
most eloquent plea along this line. HIec-
trie transmission is convenient, but it
is not cheap, as many have learned after
a change from one system to the other.

When an owner or manager is ap-
proached with a proposal to change Irotii
one system to another, sound business
instinct should dictate that not only
should the claims of the new system be

as rigidly investigated as would be the
commercial standing of a new customer
who wished to make a long-time con-
tract, or the merits of a substitute ma-
terial for manufacturing purposes. Power-
plant records, which should be kept as
scrupulously accurate as the accounts of
any other department, will show whether
a change is advisable.

If plant records are not kept the cus-
tom should be instituted at once. It is
highly probable that the information
gained in this way will pay for its cost
many times in the improvement which
invariably follows a change from a slip-
shod lack of method to business ways
of doing common things.

Boiler Efficiency

When the American Society of Mechan-
ical Engineers' committee on rules for
power-plant tests wakes up it might
profitably devote a few minutes to Rule
XXI of the "Code for Conducting Boiler
Tests." This rule states that the efficiency
of a boiler is the ratio:

Heal absorbed per pound oj combustible

Calorific value of i pound o] combustible
and that the efficiency of the boiler and
grate combined is the ratio:

Heat iiftxir/fi/ />. i pound of coat
Calorific valw oj i pound of coal

With no definition of "combustible,"
these two formulas give precisely the
same results. For example, if the coal
contains ninety per cent, of combustible,
both the numerator and the denominator
of the second ratio will be numerically
ten per cent, smaller than those of the
first ratio, but the results of th« two will
be exactly equal.

Of course, we are familiar with the
methods commonly followed in making
boiler tests, and in the light of such
familiarity it becomes clear that the
"combustible" in the numerator of the
first ratio means that part of the fired
combustible which is actually burned
that is. does not fall through the grate,
but the code docs not say so and that is
not the definition of the term for any
purpose other than boiler testing. There-
fore, the first ratio is nol stat"d "ith
abstract clearness. It should read:
Heat nhtntbed per pound eombuttihle burned

Heal : alur of I pound rombuttiNe
The second ratio, for overall cBlciency,
would be improved by adding the word
"fired" after the word "coal" In the
numerator.

POWER

November 7, 191 1

Btfilcrs umier Sidewalks

Nowhere is the inconsistency of city,
State or Government control over the
safety of the public more in evidence
than in the matter of boiler installation.
On the statute books of every town, city
and State are laws prohibiting persons
who have no regard for the safety or
welfare of others from doing certain
things, and such laws are based on sound
common sense. Why, then, should not laws
be enacted to govern the placing of steam
boilers?

Under the present laws of most cities
the owner of a steam boiler can put it
wherever he pleases, except in the street,
and permits are issued even for this
purpose. Thousands pass these boilers
every day who are ignorant of the dan-
ger to which they are exposed from an
explosion.

In hundreds of instances the steam
boilers of buildings are placed beneath
the sidewalk. They are thus installed
because they are convenient for coal de-
livery and because the owner of the
building secures a larger basement area.
No consideration is given to public safety
and few passersby know that the boilers
are so placed until the building has
been torn down or an explosion occurs.

An example of what may happen
at any time, and particularly in a con-
gested area, occurred in New York City
recently, when a return-tubular boiler
exploded, an account of which explosion
has been published.

It is true that for twenty-three years
this boiler had been under steam pres-
sure without accident, but one night it
exploded and demolished the sidewalk
for more than half a block, throwing
tubes, bricks and fragments of flag-
ging into the street and the adjoining
buildings. It is fortunate that the streets
were deserted at the time of the explo-
sion, save for a solitary policeman who
was standing on a street corner half a
block away, and he was injured.

What would have been the property
damage, what would have been the death
toll, and how many would have been
injured had the boiler exploded at noon
instead of at midnight?

Is it safer to put a boiler under the side-
walk than it is to place it in the base-
ment of a building? We do not believe
that it is. It is true that the destruction
of property might be greater when a
boiler in the basement explodes, for the
building would be partially wrecked and
strained. But when a boiler installed
under a sidewalk explodes during the
busy hours one might as well train a
gatling gun on the people.

It is good fortune that no lives were
lost in this explosion, but the lesson to
be drawn from it is that greater vigilance
should be exercised over all boilers so
located, though the chances are that the

old lap-seam boilers will continue to be
operated under the sidewalk as they have
for years past.

Smoke Inspection

Elsewhere in this issue will be found
reference to some of the activities of the
smoke-inspection department of the city
of Chicago. Although this particular in-
stance applies to the marine branch of
the bureau, similar steps have also been
taken relative to stationary plants.

The policy followed by this department
is established on broad and comprehen-
sive lines; instead of arbitrarily enforc-
ing the law and leaving the offender to
seek his own remedy, the department co-
operates with the latter and gives the
benefit of its extended experience.

A similar policy has been adopted by
the city of Boston. There the law has
established the standards by which the
density of the smoke is to be judged;
it prescribes what density is permissible,
and provides for a definite penalty. By
this means the owner or the engineer, by
exercising close supervision 'Over the
plant, is able to judge whether the law
is being transgressed.

Furthermore, the smoke-inspection de-
partment has made extensive experiments
in smokeless combustion with various
fuels and, as in Chicago, cooperates with
the plant owners, advising them as to
the type of furnace to be employed with
different fuels, the methods of firing best
adapted, etc.

It would seem that New York City
might profitably follow the lead taken
by these two cities in the enforcement
of such an important ordinance as that
relating to smoke nuisances. While it
is true that much of the coal in the
Chicago markets has more smoke-form-
ing qualities than that available for use
in New York, yet the latter does not dif-
fer materially from that used in Boston.

In New York there is no distinct smoke-
inspection department, the duties of such
being performed by the health depart-
ment. Furthermore, the law merely
states that no dense smoke shall be emit-
ted from any stack within the city limits,
and provides for fining the offender. The
question of density is left entirely to the
judgment of the inspector and the owner
is offered no assistance in relieving the
conditions.

It is now well known that practically
smokeless combustion can be obtained
with bituminous coal, providing the
proper type of furnace and the correct
methods of firing are employed. Different
coals and boiler equipment require dif-
ferent treatments, however, and the diffi-
culty lies in the fact that the average
owner or engineer of the small plant has
not had the experience which will en
able him to meet individual plant condi-
tions with smokeless combustion when
burning bituminous coal. Therefore, he

turns to anthracite, which, of course, pre-
cludes the use of mechanical stokers.

In view of this, cooperation of the
smoke-inspection department (which has
the facilities for making a thorough study
of all conditions) with the owner is most
desirable.

Terminal Pressure and
Compression

It sometimes happens that an engine
which runs quietly with a certain steam
pressure and load will begin to pound if
either are changed. This oftenest occurs
when the load is increased or the pres-
sure diminished.

.\s the piston approaches the end of
the stroke its velocity decreases rapidly
and at the end becomes zero.

While the piston is moving through
the cylinder with the steam behind it the
pressure on all of the pins and bearings
is in one direction and all of the lost
motion necessary for lubrication in the
reciprocating and stationary joints is
taken up in this direction. If near the
end of the piston travel the exhaust
valve is closed and steam enough is
caught in the clearance space to raise the
pressure in front of the piston above that
behind it, it will tend to reverse the di-
r£Ction of the pressure on the pins
gradually and the piston will start on the
leturn stroke quietly. If, however, the
compression is not enough higher than
the terminal pressure on the opposite
side of the piston to take up the inertia
of the moving parts, the reversal will be
accomplished suddenly by the steam
which enters the cylinders as the steam
valve opens and the engine will pound
unless very closely keyed.

If an engine is running quietiv with
normal load and steam pressure with a
compression sufficiently above the ter-
minal pressure to gently affect the mov-
ing parts as they come to rest, and either
the load is increased or the steam pres-
sure reduced the terminal pressure in
the cylinder will be increased. If the
increase in the terminal pressure is high
enough to nullify the effect of a slight
compression the engine will, unless close-
ly adjusted, change from a quietly run-
ning machine to a noisy one.

In the operation of cross-compound
condensing engines it often happens that
an increase in the receiver pressure will
make the low-pressure side pound on the
centers because the higher pressure in
the cylinder at the end of the stroke
brings about a more sudden reversal in
the direction of pressure on pins and
journal, taking up the lost motion with a
thump instead of gradually as is de-
sirable.

If will be found in a great many cases
that it is excessive lead rather than the
lack of compression that causes the
pounding that can only be cured by ex-
cessive compression.

November

1911

P O V(' E R

715

Heating and Ventilation

School Heating

By Ira N. Evanst

In schools of the high and manual-
training class, where rooms aggregate
more than 16 and the pupils over 500,
engines are included for power purposes
with increasing frequency in connection
with the use of exhaust steam for heat-
ing.

The peculiar conditions of school op-
eration make this arrangement econom-
ical, as the lighting and power are re-
quired during sessions, and the summer
vacation reduces the number of hours to
practically the heating season.

The site requirements for light and air
reduce the lighting load to periods of
school sessions in winter and the fresh
warm-air requirements for occupants in-
sure ample boiler capacity for power
purposes before utilizing the exhaust in
the heating system.

In the article of September 12, the
hours of operation for the heating sea-
son are given in Table 2 as 5036 for
the New York district with 10-hour day
periods. Deducting 31 Saturdays of five
hours each, or 155 hours, and taking
eight-tenths of the result, the number of

actually in operation 22 per cent, of the
time and outside of public uses, nights,
etc.. are closed 78 per cent, of the time
during the average heating season in
the New York district.

The law in most States requires that
school buildings be provided with a sys-
tem of air supply and removal which will
furnish a minimum of 30 cubic feet of
air per pupil per minute heated to 70
degrees Fahrenheit. In small buildings
this has been accomplished with a hot-
air furnace and a gravity circulation of
air with fair success. When the build-
ing in question has over six rooms and

lA. >'LTH High School, Wor-
cester, Mass.

hours for school children during the heat-
ing sea.'ion are obtained. This contem-
plates an operating-day period of from 8
I a.m. until 4 p.m. The hours deducted
> from day periods should be added to the
night and holiday periods and the per-
centages of Fig. 3 in the September 12
article applied to obtain the number of
' hours for each in. decree period of out-
' side temperature. This gives a day op-

eration of 1112 hours and a night and
holiday operation of

5036 1112 .3024 hours
Table 1 gives the number of hours as
described. This shows that schools are

•r<n,jrlcliti-<l. mil

Ira N. Krnnw

^ . .._ licnllni; iin»l

l.-.n Itr'Hiilw*r. N-w York r'tlr.

Fir, IB. BhiiCKTon Hir.H school

the inspectors insist on a proper air
supply, the apparatus becomes so bulky
and expensive to operate that this system
must be abandoned.

For six- and eight-room schools a
gravity steam system is employed with
indirect radiators to heat the air supply,
which in turn depends on gravity for its
operation, with the attendant low veloc-
ities and large flues. Auxiliary direct
radiation in the rooms may be used as
well. Aspirating coils are also used in
the ventilating Hues to produce a move-
ment of air in moderate weather. This
is a wasteful method except on a small
scale and at the time most needed- mod-
erate, damp weather — is likely to fail.
In cold, clear days the hot air in the

room will create sufficient draft without
the aspirating system.

In cases where public-ser\'ice current
is available, motors may be used to drive
the fan. This reduces the size of flues
.nnd gives a positive assurance of re-
sults.

In school plants there seems to be a
desire to eliminate all apparatus pos-
sible that would require knowledge and
intelligence in the man in charge, so that
the heating plant for large buildings is
often designed in the same manner as
for small schools. This involves heavy
operating expense in the number of boil-
ers, fuel and purchase of outside power.
-At the same time knowledge and experi-
ence on the part of the engineer will
be found a valuable asset in either case,
as the fuel and repair bill is apt to be
a greater expense than is the extra in-
vestment in management.

Spare boilers, which are unnecessary
in school work, are installed in many
cases; and no matter how many are in-
stalled, all are likely to be operated to
make easier work, thus increasing the
repair bill and expense attendant on op-
crating extra fires. Due to the general
durability of boilers and the frequent

Fic. IC. Salhm Hir.n School

intervals between school sessions, any
possible breakdown can be handled so
as not to interfere with the operation
of the plant if the boilers are kept in
any kind of general repair. With the
wide range in steam requirements for
heating, a properly designed system
should operate on .50 per cent, of the
boiler power required in extreme weather,
or SO per cent, of the time.

Many schools arc provided with low-
pressure gravity-return systems for the
direct radiation, with a separate high-
pressure boiler to operate the fan en-
gines, utilizing the exhaust steam in the
fan heater. This requires a greater num-
ber of boilers than if they were all op-
erated on high pressure and the steam

M6

POWER

November 7. 191 1

taken through a reducing valve; but the
use of a pump and receiver during non-
sessions is eliminated. Gas engines have
also been used to operate fans and do
away with operatinf^ the boilers under
high pressure. All of these schemes have
for their object the elimination of in-
telligent labor at the expense of coal
and proper apparatus and do not accom-
plish the result desired of a lower total
operating cost.

The following are the basic methods of
arranging the heating system for large
buildings in cold climates:

1. The heating proper may be done
by low-pressure steam returning to the
boiler by gravity or high-pressure steam
on the boilers with a reducing valve to
lower the pressure of the steam before
it enters the heating system. In the
latter case a pump and receiver are re-
quired to return the condensation to the
boilers.

2. Hot-water forced circulation with
high-pressure boilers and a live-steam
heater with gravity return for all con-
densation. An exhaust heater is also
provided in the water circuit for the use
of any exhaust steam from power. These,
with two pumps all in series in the water
circuit, constitute the hot-water system
shown in Fig. 5.

In many schools the radiation is very
near the water line of the boilers, thus
reducing the operating pressure in many
cases to 2 to 5 pounds, so that the
condensation will flow from the radiators.

Se.s

.■OKS

N'ON-.SK

.s,„xs

Temp..
Deg. F.

%

Hour.s

c-

Hours

0-10
10-20
20-30
SO-40
40-50
.50-60

0.6
3.25
13.25
32.4
22.7
27.8

7
36
148
360
252
309

1.6
6.13
17.83
27.82
22 . 42
24.2

63
241

700

1,091

.879

950

Totals..

100.00

1,112

100.00

3,924

The low-pressure steam system re-
quires the use of drain traps and ex-
pensive trench work to allow a proper
cradient, all of which is unnecessary on
the water system, due to the pump in
the circuit. The mains may be run over-
head and exposed as radiating surface,
reducing the temperature of the circulated
water by that amount. The expensive
covering required for steam systems is
eliminated except in the boiler and en-
gine rooms.

The live-steam heater arrangement al-
lows any pressure to be carried on the
boilers and a gravity return for the con-
densation is maintained. The boilers may
be operated at the same pressure for
both power and heating, the exhaust
heater utilizing the heat of the exhaust
steam.

In all school work the heating load is
in excess of any power requirements,
and a pressure above atmosphere suffi-

cient to remove the air is always avail-
able. With the higher temperature, due
to the greater pressure, less surface may
be used, and mechanical appliances to
produce vacuum and operate t'.ie system
below atmosphere are unnecessary. A
back pressure is not objectionable under
these conditions and automatic heat con-
trol will reduce the heating steam to a
minimum. In making the foregoing state-
ment it is presupposed that the system
of piping is properly arranged, as there
have been cases where a bad piping
layout has been remedied by the use of
a vacuum system.

The ventilation and fresh-air supply
may be arranged as follows, but one of
the above systems is necessary in con-
junction:

1. Plenum system with a central
stack to heat the outside air to 70 de-
grees and a supplementary heating stack

.A_,n

crating in conjunction with the several
thermostats.

4. In a few cases a system of ex-
haust ventilation only has been provided,
openings being made from the outside to
individual direct-indh-ecf radiators or to
indirect radiators in the basement with
heating flues leading to each room. The
operation of this system depends on the
suction produced by the exhaust fan in
the attic to cause a flow of fresh, warm
air into the rooms. This system is apt
to be unsatisfactory as there is no surety
when exhausting air that it will flow
from the point desired.

5. Direct radiation operated inde-
pendently in the rooms with either steam
or water circulation for periods of non-
session and a plenum system of air sup-
ply furnishing warm air at 70 degrees
during school sessions only. The fan
may be operated by engine or motor.

Iki

:^^^m.

ir~rirT

Fig. 2. General Plan of Base.ment at BfincKtoN School

for air at high temperature distributed
through a double-duct system to each
flue, with a mixing damper thermostatical-
ly controlled.

2. Plenum system with central stack
and individual auxiliary stacks at the
base of each flue thermostatically con-
trolled.

3. These rules may be modified by
concentrating the several individual stacks
at the base of each group of flues. A
switch damper is provided thermostatical-
ly controlled so as to take air at 70
degrees from below the stack or at a
higher temperature from above. The
thermostat in each room controls the
damper in each flue so that as they are
turned off the cold rooms have the con-
centrated power of the entire stack. When
the last of the series is taking air at
70 degrees from below, the steam is
shut off the entire stack by a relay op-

.All the above systems except No. 4
may include a system of ventilation com-
posed of vent flues with a fan and motor
in the attic or a system of aspirating
coils in the flues for exhaust ventilation.

The double-duct system does away
with distributing steam pipes to auxiliar>'
stacks, but the hot-air ducts require a
greater expense in insulation. The large
ducts and the low specific heat of the
air make the losses by radiation a serious
matter. Mixing dampers are almost im-
possible to adjust on account of mixing
air at different temperatures at various
distances from the source of heat and
attempting to maintain a constant tem-
perature in the room with the variable
mixture of entering air.

The system involving individual stacks
is very expensive, due to the large
distributing steam pipes and their
covering. Traps and trenches for re-

November 7, 191 1

POWER

717

urns are also expensive items. A pump
nd receiver would also be required, as
'. most cases, on account of levels, it is
•^possible to return the condensation to
/e boilers by gravity.
The modification of combining the

require power lo operate the fan during
nonsession periods, and this may mean
a greater steam consumption than is nec-
essary for the heating, especially in mod-
erate weather.

.Ml plenum systems are e.\pensive to

outdoor air, there is little difference in
the operating expense of all of the sys-
tems at that time. The occupants fur-
nish about 300 B.t.u. per hour each in
bodily heat, and with 40 or 50 in a room
this heat with the fresh-air supply is

r'

J

\ lnd!rect Sfacks ^ ^ I -j=ppfxAo(ysfM7?(:/7cA^.,| I -.^j^l

P — \ ' — t ^^ir'-'^l jr5^ Enqine Room .:

Air Shaft -\ i±i:L,z^l ,-€!■ '^-Jr.irJy^ ^-

Fic. .S. Plan of Sibbask.ment, Shoviing Pow er Plant

auxiliar>' stacks is open to the same ob- operate during nonsession periods, even sufficient to maintain the temperature, cx-

jeciions except for a reduction in the when provision is made to recirculate the cept in extreme weather,

number of indirect-radiator sections. In- air. The necessity for the system of There is quite a divergence of opinion

direct radiators are difficult to keep tight ventilation for each room causes a large as to the positions of inlets and outlets

"here the steam is turned on and off portion of the heated air to escape, and for air in class rooms. It all depends on

Fir,. \. StCTIONAI. ElEVATION THRniT.H PriWrR PiXNT

frequently with thennostalic control, due
to expansion strains. If very low steam
pressure is used, it is sometimes difficult
(n relieve the stacks of air and flII them
with steam quickly. All blower systems

all systems are open to the objection of
high steam consumption in extreme
weather and radiation losses in transmis-
sion. Due to the fresh-air requirements
during sessions and the use of entirely

the density and weight of the air, which
varies inversely as its temperature,
whether it is foul <!>x fresh. When heal-
ing alone is desired the entering air must
be warmer and lighter than the air of

718

POWER

November 7, 1911

the room and the exit should be at the
bottom. When the occupants exhale air
and heat is radiated from their bodies,
the foul air of any room containing a
large number of pupils per cubic con-
tents is lighter than the incoming air
and the outlet should be at the ceiling.
For a perfect system, both the top and
the bottom ventilation should be provided
with a register at the ceiling automatical-
ly closed when the room is below the
temperature of the incoming air and
opened when conditions are reversed.
This register may be operated in con-
junction with the automatic heat control
on the direct surface or the auxiliary
stack.

The size of the ordinary class room
and the frequent air change prevent the
temperature changing materially from
that of the incoming air and the top
register is generally dispensed with in
school work without serious results. It
is generally agreed that 8 feet from the
floor is the proper point for the air inlet.

The foregoing conditions are true for
any auditorium holding a large number
of people. The bodily heat is sufficient
to raise the temperature in conjunction
with the necessary volume of entering
fresh air which falls and diffuses to a
lower temperature without causing drafts.
The foul air is then taken through a
large ventilator in the ceiling. This con-
dition is reversed when the building is
cold and heat ic required with no audi-
ence present. The larger the building
or auditorium the more necessary is top
ventilation when people are present.

As to the position of the inlet and out-
let with regard to the sides of the room,
it makes little difference if the velocities
are low. The level and difference in
temperature of the contained and entering
air form the all important point. The
fifth method, being the most economical
of operation, will be described most fu41y.

Fig. 1 shows photographs of three
large schools in New England equipped
with direct radiation for nonsession heat-
ing and a fresh-air supply for periods
during sessions, all heated by a system
of forced circulation of hot water. The
boilers are operated at from 80 to 100
pounds pressure and all the exhaust
steam is utilized in the heating system.
The South Side high school at Worcester,
Mass., which accommodates 900 pupils,
requires an air supply of 45,000 cubic
feet of air per minute and an 85-horse-
power boiler.

The annual report of the superintend-
ent of buildings at Worcester debits this
school with ^521 for fuel for the year
ending November, 1910. The English
high school in Worcester, of the same
size and operated on steam from a high-
pressure boiler used for power, and em-
ploying a gravity-return low-pressure sys-
tem for the heating proper, is debited
with $1547 for fuel. Electrical energy
from an outside source to operate a 5-

horsepower motor on the direct-heating
system, nights, was charged at SI 15 for
the South Side school.

This is a difference of $900 in favor
of the hot-water school, and at that the
motor could easily be done away with
by operating the plant nights. The cold-
est weather known to Worcester is — 10
degrees and this school has never been
dismissed for lack of proper heating in
eight years, which is not true of some
others.

As the total cost of fuel from author-
itative sources is given and the number
of session-hours, it would possibly be of
interest to know the cost of operating
the fan by outside power. For the
school sessions during the heating sea-
son. Table 1 gives 1120 hours, and a
motor of 28 horsepower capacity, or 21
kilowatts, will furnish power for 45,000
cubic feet of air per minute against -U
to I ounce pressure. Assuming a charge
of 4 cents per kilowatt-hour, the cost
would be

21 V 4 :< 1120 r= 940.80 dollars
per year, or about twice the cost of the
luel. It is thus apparent that there would
be no profit in purchasing power for
school work and the saving would pay
for good talent to operate the plant at
liigh pressure to supply the engine equip-
ment.

Fig. 1, C, is a large high school at
Salem, Mass., with about 1500 sittings,
which is equipped with two boilers of
110 horsepower capacity each; one only
is operated except in very extreme
weather. The lowest temperature at this
latitude is — 15 degrees Fahrenheit.

Fig. 1, B, is the Brod^ton high school
with accommodations for 1500 pupils
and the same equipment of boilers as at
Salem. The Brockton school has two
direct-connected units of 25 kilowatts
and 50 kilowatts capacity for lighting and
operating motors for the manual-training
department. The air supply is 65.000
cubic feet per minute and only one of
the 1 lO-horsepower boilers is operated
except in extreme weather. The hot-
water plant consists of two De Laval
centrifugal pumps direct-connected to 15-
horsepower turbines of the gearless type,
having a capacity of 650 gallons per
minute against a 60-foot head; the water
connections are in series. The exhaust
heater is built of iron with a shell 5 feet
in diameter and contains 338 two-inch
tubes 6 feet long, which are capable of
condensing 4000 pounds of exhaust
steam per hour. The live-steam heater
is placed vertically in this school and is
built of iron with a shell 3 feet 6 inches
in diameter with 144 fubes 2 inches in
diameter and 5 feet long, capable of con-
densing 8000 pounds of steam per hour
as a maximum. In Figs. 3, 4 and 5 a
horizontal heater is shown; this should
be of brass tubes of the same capacity
on account of the horizontal position re-
quiring provision for expansion.

Fig. 2 shows the general arrangement
of the basement of the Brockton school.
Due to lack of appropriation, the entire
building was not constructed and two
front rooms, in the basement, were used
for a power plant. These rooms are
valuable space and besides the machin-
ery is badly crowded. Fig. 3 shows the
arrangement of the subbasement as or-
iginally intended before the appropriation
was reduced and is applicable to many
schools when built on the hollow-square
plan. Figs. 3, 4 and 5 show how by ex-
cavating 10 feet below the basement-floor
level and carrying the main walls of the
building down at slight expense, a light
boiler and engine room can be had and
ample coal-bunker space provided. This
gives the use of the basement rooms for
school purposes exclusively. It is a vital
point in designing an economical plant
to have plenty of space for repairing and
cleaning the boilers and engines without
too much effort.

Fig. 2 shows the air ducts in the cor-
ridors, which may be built inexpensively
by furring the corridor ceiling, leaving
only the branches to be built of gal-
vanized iron. The large coal bunker
takes up the dead space behind the front
steps. A corridor with tracks connects
with the boiler room.

The boiler and engine room is framed
with two large skyliplits between the
central and main walls of the building,
which will form a light shaft when the
additions are completed. There is a
passageway around the skylights and
two openings are left, one on either side
of the projection forming the fan and
heater room for light and air. One is
used for the fresh-air inlet to the fan,
which when the building is completed
will be practically taken from the roof
level.

In the general plan of boiler and en-
gine room are shown all piping and ma-
chinery. The live-steam heater is ar-
ranged high on the wall between the
boiler and engine room, with a gravity
return to the two boilers which are con-
nected to a self-supporting stack for
draft. The exhaust pipe is in a trench in
the engine-room floor, and the steam
passes through an oil separator to the
feed-water and exhaust heaters before
entering the outboard exhaust pipe. A
bypass is also formed around these heat-
ers that the latter may be cut out at
any time. The drip from this apparatus
drains to a small tank connected with
the feed pump. A blowoPf tank and
sump pump in the rear of the boiler room
take care of the blowoff from the boil-
ers and the drainage from the oil sep-
arator and oily drips. The automatically
operated sump pump empties the blowoff
tank to the sewer.

The fan may be operated by motor or
engine as desired. The air is discharged
through a vertical flue to the ceiling of
the basement corridor, as shown in Fig.

November 7. 1911

POWER

719

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720

POWER

November 7, 1911

able to supply sufficient heat, if the sys-
tem of direct radiation gets out of order,
until the latter can be repaired.

Fig. 5 also shows one wing arranged
with an overhead system which is adapted
to a building of over four stories. Supply
and return risers are run as shown- and
coils or radiators may be used for heat-
ing surface. The risers in this case
should have valves top and bottom with
drawoffs. These risers may be reduced
to l]4 inches with 1-inch connections to
the coils and radiators. Attention is
called to the method of connecting tlie
surface in the basement.

This building has the usual assembly
hall and gymnasium, and the fresh-air
supply is so arranged that it may be cut
out when these places are unoccupied.
Direct radiation is provided to keep them
warm when not in use.

A ventilating system is provided to re-
move the foul air with two fans operated
by motors in the attic. The toilet rooms
and chemical laboratories are ventilated
by a separate system on account of the
odors when the fan is inoperative.

The expansion tank may be placed in
the attic and equipped with a water-
feeder pop valve; it is shown in the
sketches of the boiler room to be handled
by air pressure. This arrangement may
be modified to suit any high school. With
small pipes and eliminating trenches and
expensive covering, the first cost and
operating expense should be low. No
school should have more than two boil-
ers, and when the horizontal tubular
units are too large, water-tubf boilers
will be found advantageous, as the
greater the number of fires the more is
the operating expense increased.

Thermostatic control is used on hot
water in the same manner as steain, but
with the division of circuits the water job
can be easily controlled by hand. Thermo-
stats may be arranged to control the
flow of water in the four circuits of the
building by taking the room of the group
supplied most likely to give the best
average temperature for the position of
the thermostat.

It must be borne in mind that in shut-
ting off a hot-water coil or circuit the
heat is not reduced until the water in
the coils and radiators cools. Fig. 5 also
shows the water connections for the heat-
ers, pumps, expansion tank and the fan
coil.

In the Brockton school there is 65,000
cubic feet of air supplied and 14,000
square feet-of direct radiation, and there
is little difference in the heating during
sessions when the- air supply is required.
A comparison of the nonsession periods
will show the saving of one system over
another.

In figuring the cost of heating, con-
tinuous operation is intended, although
many schools, including the South Side
school at Worcester, are not operated
nights except in extreme weather. There

is no saving in fuel by this method and
the low-pressure steam. The steam sys-
tem is expensive in operation, due to the
low-pressure boilers and vapor losses.
To raise the teinperature of 50,-
000 cubic feet of air one degree, one
pound of steam will be required. The
transmission of the direct surface will
be taken as 1.8 B.t.u. per hour per de-
gree difference in the temperature of the
pipes or water and the room. Take the
room temperature at 65 degrees for non-
sessions and the latent heat of steam at
1000 B.t.u. Then

14,000 X 1.8

= 2 5. J pounds

1000

for each degree difference in the tem-
perature of the water and the air of the
room. If coal is bought at $4 per ton, of
2000 pounds, and an evaporation of eight
pounds is obtained, then the cost for
1000 pounds of steam will be

4 X 1000

2000 X 8
The fan system

= 0.2,') or 2 J cents

will require a 50-

horsepower engine using approximately

S250, or a saving of 13 per cent, for
direct radiation over the fan system.

In a certain large city the janitors are
required to hold an engineers' license
and they receive a lump sum for the
labor involved in cleaning and operat-
ing the heating plant; the city furnishes
the coal. Some of these buildings con-
tain over a hundred class rooms and re-
quire a large boiler plant. Every con-
ceivable scheme is resorted to in order to
reduce night operation: gas engines,
extra high-pressure boilers and outside
power. It is customary to shut the heat-
ing plant down nights except what heat
can be obtained from banked fires and
thus get rid of a night man. In the morn-
ing about 20 or 30 pounds pressure is
put on and the fan started; 200 horse-
power for 10 hours is crowded into about
two hours, or into the shortest space of
time that the capacity of the installed
boiler plant will permit. This naturally
results in great waste of coal at S4 per
ton and the operation of more boilers
than necessary, just to get rid of the
$2 to S2.50 wage for a night fireman.

lABLE 2. NONSESSION>

Hours

Non-
sessions

1)11

T,..^

,

'l.KVIM Si

vrK.^,

Outside
DcK. P.

Av.
Temp.
Water,
Deg. Tt:

Dif

Temp.

be-
tween
Pipes
and
Roorn,
Deg. F.

Pounds

.Steam per

Hour

Pounds

Steam per

8.eason

Temp.

Factors

Pounds

Steam per

Hour

Pounds

Steam per

Season

0-10
10-20
20-30
;i0-40
40-50

63

241

700

1,091

879

190
180
170
150
140

125
115
105
85

3,l.itl
2.898
2,646
2,142
1.890

19S,4,-)0

698,418

1.852,200

2,336,922

1.661,310

0 . s.-,
0.60
0.5
fan
engine

4,309
3.295
2. .-.35
2,500
2,500

271,467

794.095

1.774,500

2,727,.i00

2,197,.50O

Total.. .

6,747,300 !

7,765,062

50 pounds of steam per horsepower-hour
and 2500 pounds per hour will be the
minimum for any period on the fan sys-
tem. The circulating pump will require
15 horsepower at a maximum of 70
pounds, or 1050 pounds, and this will
be the minimum for the hot-water sys-
tem on direct radiation. This pump must
have capacity for the indirect stack which
is inoperative at these periods.
For the fan system in zero weather

6.s,ooo
50,000

X 60 X 65 = .S070

pounds of steam per hour will be re-
quired. Table 2 gives the factors and
hours for nonsessions froin Table 1. also
the requirements for direct radiation on
hot water. The system is discontinued
at 50 degrees outside temperature.

As shown in the table, the saving of
direct radiation over the plenum system
is

7,765,000 — 6,747,000 = 1,018,000

pounds

of steam per season. At 25 cents per

1000 pounds, this means a little over

If a bonus was given the engineer-
janitor for each ton of coal saved one
season over another, this method of op-
eration would be abandoned, a less num-
ber of boilers would be required and the
engineer would find that there was a
much greater saving to be made in the
coal than in the labor.

As it is at present, the city pays ten
times as much for coal to operate the
schools intermittently as the night labor
would cost, and about double the boiler
capacity necessary is installed with the
attendant cost of inaintenance. Hot
water would be the favorite system of
heating for continuous operation.

Cheaper coal and better loading facili-
ties have led the White Star line to adopt
the practice of taking aboard coal in New
York for a round trip, and it is quite
likely that other transatlantic steamers
will adopt the practice. It is said that
domestic bunker coal is averaging higher
in quality than most of the bunker coals
of western Europe and is being supplied
at considerable less cost.

November 7, 1011

P O W F R

Performance of the Fi

My attention has been attracted by
what has appeared in some of the recent
issues of Power regarding the Christie
air-steam engine, in which connection
some of the readers may be interested
in another «rir and steam engine which
was built and operated about 17 years
ago in Scotland.

This engine operated on a mixture of
steam and air, employing the two-stroke
cycle, and was supplied with hot air
from an outside source. Test results of
this engine are available, and are stated
in terms of both indicated and brake
horsepower.

A brief description of the engine and
of the tests made by Professor Jamieson
forms the subject of a paper presented to
the Institution of Engineers and Ship-
builders of Scotland, on April 30, 1895.
Speaking of the engine under descrip-
tion. Professor Jamieson says:

"This invention is, 1 understand, the
joint design of Edward Field, inventor
of Field's \reU known tubular boiler.
F. Saunders Morris, working in con-
junction with Musgrave & Co.. of Bol-
ton, and George Dixon, their chief engi-
neer.

"It consists of a hot-air pipe connec-
tion to the jacket and to each end of a

By L. B. Lent

Dt

'scriplion

and

test re-

suits

of a steam-air

engine

hid If

in Scotland in

1894.

hi

spite of an apparently 1

javorable slioii

■ing

the cii-

S' "€

nei-er alia

ined

promi-

)lCIICi

mained open until compression com-
menced, being held close to their seats
by light spiral springs, as shown in the
sketch. Consequently, the whole in-
ternal surface of the cylinder was
heated to a temperature far exceeding
that of the steam, thus preventing the
possibility of condensation taking place
within the cylinder. Under these cir-
cumstances, I got the excellent result of
18.6 pounds of steam per indicated horse-
power-hour from a single-cylinder non-
condensing engine, a result which, as
far as I can learn, has never been
equaled by any other method of using
steam in a single cylinder, and without
subsequent condensation."

SeCTION THROUGH CYLINDER AND HEAD OF FlELD ENGINE

single-cylinder noncondensing engine.
A Roots blower, driven by the engine,
draws fresh cold air fiom the engine
room, and forces it through a series of
heating pipes placed in the main flue be-
tween the boilers and the chimney. This
heater, therefore, occupies much the
same position as a Green's economizer.
"In my experiments, the air was main-^
tained at a mean pressure of 1 >■ pound
per square inch, and delivered io the
end of the cylinder at a mean tempera-
ture of .'i,'^.3 decrees Fahrenheit, and to
the valve-casing jacket at about 38<1
degrees Fahrenheit. This hot air was
admitted to the cylinder ihrouch special
cylinder covers, each containing five in-
let valves, which automatically opened
inwardly as soon as the exhaust steam
commenced to escape. These valves re-

Without quoting in full Professor
Jamieson's description of the specific
arrangement of the boiler, heater, blower
and engine, and of all the test apparatus,
suffice it to say that the described
method of test showed that every care
Wis taken to accurately measure the de-
fed quantities and that all instruments,
''such as feed-water g.Tges, tanks, ther-
mometers, indicators, etc.. were rarefully
calibrated before and after the lest, and
all measurements were made in an ap-
proved manner calculated to insure the
greatest accuracy and correctness of re-
sults.

Quoting again from the paper:
"Steam was kept as steadily as possible
at an average pressure of 11.^ pounds
per square inch, and was supplied very
dry from the superheater to a Corliss

721

eld Engine

engine made by Musgrave & Co. There
was nothing special about this engine,
except the application of Field's arrange-
ment; in fact, the engine had not a high
mechanical efficiency, since the ratio of
its brake horsepower to its indicated
horsepower had been found by Professor
Kennedy to be only 83 per cent."

No reference is made in the paper to
the quality of the steam delivered to the
engine other than that stated. However,
I am inclined to believe, from an exami-
nation of the ordinary Cornish boiler
and a knowledge of its construction at
that date, that the steam was but slightly
superheated, if at all. Since the steam
quality is unknown it is impossible to say
how much effect it had on the economic
results obtained, but probably it was a
very small effect.

It is stated that in Professor Ken-
nedy's test of the same engine, under
nearly the same load conditions as those
existing in the tests under discussion,
and running as an ordinary steam engine,
the steam consumption v.as 31 pounds
per indicated horsepower-hour.

A summary of the principal results
of Professor Jamieson's tests is given
in the following table:

.<tM.\i.\i!Y oi- t;;sts

Novem- Uecom-

Daif ot ti'sl. her 30, ber I,

isn4 l.soi

(3 hours,
20 min-
utes

Mi-an cro?».'*-st*cl ional area of

cvlinder. square inches .. . 280.8 iSO.S

I.inclh of stroke, feel .. : . . 2.997 2.997

M>an revolutions per minute 81.6ti 82 23

Mvan Imilir pressure, b.v
Kace. [>ounds per squan'
inch 113.4 113 1

Mean initial tyliniliT pres-
sure b.v indicator carils.
Iiounds |H'r square inch,
eage 113.4 110.7

■[■(■rminal pressure b.v indica-
tor cards, pounds pt»r
M|uare inch cage

.Mean elTeclive prt»sstin*.

pounds IMT square inch 32 13 4

Mean pressun- of liol -air sup-
ply, pounds per squan'
ini li, Kace 1 .74 18

Mean leniperature of bol-atr
~U|ipl\ to insirle of cylin-
der. ili-i;re.-s I-alirenheii .Vi3 .•.30

Mean uiiliealeil liorveiiower I36.7."> .">7 «

Mean lirake horsepower 104.8 :J2 .i

Mi'chanieal elbciencv. per
ci-nl 76.1 87 «

>ii'ain per indicatetl Iiorse-

power-hour. pounds 18.6 2t 4

.■^tiain per brake liorse-

power-liour, pound- 24.26 37 II

< ottl per indicate<l hor*e-

imwer-hour. pounds 2-4.i 3-2

'>»al |HT braki* bors*'|»ower-

lioiir. iiound- 3 21 ."• OS

It is Stated that the several alterations
which had to be made on the original
engine, in order 10 convert it to the
Field's system, were very simple, as they
merely consisted in putting on new
covers with hot-air inlet valves and hot-
air pipe attachments as shown.

Regarding the amount of power ab-
sorbed in driving the Root's blower from
the engine and heating the air. the quo-
tation from the paper is as follows: "I

722

P O W E R

November 7, 191 1

understand that Professor Kennedy esti-
mated from his tests of this same engine,
both before and after its conversion into
Field's system, and under similar con-
ditions of load, etc., that about 5 per
cent, of the indicated horsepower was
absorbed in driving the Root's blower;
but that the heating of the air in the
pipes placed in the boiler flue did not
appreciably diminish the efficiency of the
boilers nor raise the coal bill per unit
of water converted into steam. As I
had an opportunity only of testing the
engine after conversion I accept Profes-
sor Kennedy's first results, and, compar-
ing them with my first day s test, I find
that the Root's blower lowered the me-
chanical efficiency of the engine about 6
per cent."

The low steam consumption at low
loads (21.4 pounds per indicated horse-
power at about ;4 load) is very properly
pointed out in the paper; but because of
the low mechanical efficiency the steam
consumption per brake horsepower is
proportionately higher. Discussion of
the paper brought out the fact that ap-
proximately 20 pounds of air per minute
was heated from 60 to 550 degrees and

It seemes strange, however, that this
engine has not, since 1894, attained the
prominence to which such a performance
should entitle it.

A New Boiler Rating

An interesting and important result
of the increasing efficiency of mechanical
stokers is the creation of what is prac-
tically a new boiler rating. Performance
has curiously outstripped theory, and
mechanically fired boilers are found
which give a horsepower on about 6
-^I'uare feet of heating surface, over
long periods, although boiler manufactur-
1 AULt 1

Flue Tempera-
ture, Deg. F.

TS7

ers and the engineering textbooks allow
10 feet per horsepower, or even more.

The first purpose of the mechanical
stoker was to secure more steady, effi-
cient and economical burning of coal
than was easily practicable with hand
firing and to cut down the cost of labor.

eating Surface
per Horsi'-

power,

Square I'eet

S.6

6.8

Plant

Type of Boiler

Heal
Surface,

per
Horse-
power

Flue
Tempera-
ture

Buildei-s'
Hating,
Percent.

Duration
of Test,
Hours

Narragan?ett Electric I.ightinE (;o

National Museum

Com.lionwfaltll Edi^nn Co

Ev.Tctt Mills

N. V. i:.iisou Wat'Tsiil.-
Olil i:ol(iiiv stiv.-t l;;i,ilu.i\

West .Alljaiiy .Slioijs

New York Central Katiroaci

B. .t W.

C.eary W. T.

n. & W.

Manning

n. & w';

B. & W.

\ Kranldinanrt \

J Edge Moor J

B. & W.

6 4
4.97
6
.i 4S

.".. 14

544.2

4m

588
599
550
599
543
485

ISO. 4

155

201

150

179

190

193

194.5

8
16

39
8
12
14
9

forced into the engine cylinder. This
is equivalent to an extraction of 2180
B.t.u. per minute from the stack gases,
or to the conversion of less than 2>i
pounds of water into steam per minute
from and at 212 degrees Fahrenheit.

Mo inferences can be drswn from the
pert'onnances uf ihc Field enguie re-
garding the probable performance of the
Christie engine, for the cycles on which
they operate are very different. The
Field engine used hot air delivered to it
under pressure and utilized what would
be waste heat passing up the boiler
stack. The introduction of air at a tem-
perature of 550 degrees .Fahrenheit at
the commencement of the exhaust stroke
certainly must have a beneficial effect in
keeping up the tnetal temperatures. And
with an initial temperature of 550 de-
grees, the temperature at the end of
compression must certainly have been
such as to superheat steam entering at
114 pounds pressure and thus largely
prevent loss by cylinder condensation
and other heat losses. And this is all
that was claimed for this engine.

But ability to carry a large overload was
a requirement which a stoker soon had
to meet if it was to be successful. Then,
from carrying a temporary overload to
take care of a peak in the power demand,
it became practicable for certain stokers
to carry an overload of 50 per cent, for
practically all the time. This steady ptr-
'ormance was equivalent to a new rating
for the boilers. Only the gravity under-
feed type of stoker can show this per-
formance throughout a reasonably long
test, for, although some types can carry
an overload for short periods, at the end
of about four hours the necessary hand
cleaning of the fires seriously cuts down
that all-day efficiency. .Therefore, the
interesting result is that an underfeed
stoker, capable of economically burning
fiO to 70 pounds of coal per square foot
of grate and automatically cleaning fires
without checking the combustion or low-
ering the furnace temperature, has given
a new boiler rating of about 6 square
feet per horsepower for continuous ser-
vice.

How far in advance of current theory

this is will appear from a comparison of
some actual boiler tests with the require-
ments as laid down in Kent's handbook
and as expressed in the rating basis of
the best builders.

Kent prescribes 11.25 square feet of
heating surface per horsepower, and he
quotes the requirements of the American
Society of Mechanical Engineers' com-
mittee of 1899 to the effect that on this
basis a boiler should be able to carry
an overload of at least one-third its
rated capacity when being pushed re-
gardless of fuel economy.

How far behind performance are these
requirements is shown by the two accom-
panying tables. The first is Kent's esti-
mate of the forced capacity of a series
of heating-surface units and the flue-gas
temperature which corresponds in each
case. It should be noted that with a
heating surface of 5.8 square feet. Kent
gives a flue temperature of 720 degrees
Fahrenheit, which means that the fur-
nace is wasting much fuel up the stack
in order to get the high rate of combus-
tion. Kent's figures are shown in Table 1 :

Then compare the results given in
Table 2 from Taylor stoker tests.

Several important features should be
noted. In the first place. Table 2 shows
that it is possible for a stoker to carry
from 150 to 195 per cent, of rated load
for periods which would include several
hand cleanings of the fire for any other
type. This is the first essential to the
ability of a stoker to carry a continuous
excess of rating. The next point is that,
even with 190 per cent, of rated load,
the flue temperature does not exceed 600
degrees Fahrenheit — that is, the waste of
fuel up the stack is not seriously detri-
mental. In several of these cases the
flue temperature is noticeably low.

Boiler Inspectors Meet at
Boston

The second semi-annual meeting and
banquet of the American Institute of
Steam Boiler Inspecfors was held at the
American house, Bosiun. Mass., on Tues-
aa\' e\ening, October 24, and was largely
attended.

Arrangements were made by the edu-
cational committee for outside talent to
speak, it securing the services of H.
M. Feldman, representing the Chandler &
Floyd Company, who gave a very inter-
esting talk on the manufacture of Pitts-
burg "pure brand" American ingot iron,
manufactured by the .Mlegany Steel Com-
pany. A. M. Lloyd, representing the Cen-
tral Iron and Steel Company, gave a very
interesting as well as humorous talk.
Frank S. Allen, chief inspector for the
Hartford Steam Boiler Inspection and
Insurance Company, was the next speak-
er, and the relation of his experiences
during 40 years of steam-boiler inspec-
tion was immensly enjoyed.

November 7, 1911

POWER

The American Institute of Steam Boiler
Inspectors is an educational and social
organization and has had a very rapid
growth. It has among its members,
boiler inspectors from all parts of the
United States, Canada and Alaska.
Thomas G. Ranton, 112 Water street,
Boston. A\ass., is secretary.

Engine Badly Wrecked
By E. B. Emerson

On the morning of October 8, at the
the plant of the Canton (Ohio I Sheet
Steel Company, a 20x36-inch Corliss en-
gine running at a speed of 100 revolu-
tions per minute was completely wrecked.
The engine was used to drive a 400-
kilowatt alternating-curre.it generator.

Steam was furnished by four water-
tube boilers. At the time of the wreck
there was only one boiler in service, it
being the one farthest away from the en-
gine. The boilers were connected to a
14-inch header and the wrecked engine
took its steam from the end of the header
through an ell, reducer and 7-inch pipe
which in a half-circle bend dropped to
the steam chest 10 feet below the level
of the header. The header had a slight
fall toward the engine and was not pro-
vided with a separator, trap or other
means of draining the condensing water.
It being Sunday, only the engine was
drawing steam from the header, and it
would appear that enough condensation
went over into the cylinder to cause all
the trouble.

The steam chest was cracked from end
to end. The wristplate stud was broken
off, the piston rod pulled out of the pis-
ton head and the connecting rod was
bent. The cap of the main bearing was
broken into two parts, the main-bearing
pedestal was split in half and broken
off, the outboard box was broken and
the eccentric cracked. The reach rod and
all of the steam- and exhaust-valve rods
and the trip collar and dashpot rods were
bent and there were several other minor
cracks and bends.

The entire trouble could have been
avoided by the instaiUiion uf a separator
at the engine. Also, the header should
have been properly drained.

OBITUARY

As briefly announced in Poi f.r of
October 31. Robert Mather, chairman of
the board of directors of the Westing-
house Electric and Manufacturing Com-
pany, died at his home in New York
City, on October 24, of acute peritonitis.

Mr. Mather was a fine example of that
group of American railroad men who be-
gan their busintss lives in the shops and,
thus equipped with a thorough working
knowledge of mechanics, rose by their
often unaided efforts and keen grasp on
opportunities to positions of great re-
sponsibility.

Born at Salt Lake City in 1859. Robert

Mather was educated in the Galesburg
UII.) public schools, leaving the high
school at the age of 13 because he had
to earn his own living. For three years
he was learning the manufacture of
telegraph and switchboard apparatus,
when he secured a position in the master
mechanic's office of the Chicago, Burling-
ton & Quincy Railroad at its Galesburg
shops. Having meanwhile prepared him-
self for college in his spare hours, he
entered the freshman class of Knox Col-
lege in 1877. His money being exhausted
at the end of his first year, young Mather
resumed his work in the railroad office.
Reentering Knox, he graduated in 1882

Robert Mather

with the degree of A. B.; in 1885 he re-
ceived his A. M., and in 1907 the honor-
ar\' degree of LL. D.

Having been previously admitted to
the bar, Mr. Mather, in 1889, became local
attorney and from 1894 to 1902 general
attorney of the Chicago, Burlington &
Quincy Railroad.

He held high positions in the executive
boards and directorships in several of
the largest railroads in the country.

In januarv, 1909. Mr. Mather was
made chairman of the board ct directors
of the Westinghouse Electric and Manu-
facturing Company, and thereupon sev-
ered most of his railroad connections.
He was also a director of the Equitable
Life Assurance Society of the United
States, the Mercantile Trust Company,
the Havana Electric Railway Company,
the Weslinghouse Lamp Company, the
Canadian Wcstinghouse Company, the
R, D. Nutiall Company, the Niagara.
Lockporf &• Ontario Power Company, the
Perkins Electric Switch Manufacturing
Company, the Bryant Electric Company,
the National Bank of the Republic, of
Chicago; the Chicago, Rock Island &
El Paso Railway Company and general
counsel of the Chicago & Alton Railroad
Company.

Mr M.Tihrr was married in Detroit in

1892 to Alice Caroline, a daughter of
Horatio .Jell, of Walkerville. Canada.

Isolated Plant N'ictory
It is said that the Henry Siegel Com-
pany, which has been using the Edison
service in its department stores upon
Washington street, Boston, will, as soon
as its present contract expires, put in
its own plant, and has already com-
menced to accumulate apparatus for that
purpose.

PERSONAL

William Scott Taggart, member of the
German Society of A^echanical Engi-
neers and the Textile Institute, has
opened offices at 22 Bridge street, Man-
chester, England, as a consulting engi-
neer in general-engineering and textile
work.

C D. Chasteney has resigned his posi-
tion as sales manager of the De Laval
Steam Turbine Company, of Trenton,
N. J., having acquired an interest in the
Turbine Equipment Company, of 30
Church street. New York, which company
represents the De Laval Steam Turbine
Company in New York State, parts of
New Jersey and Connecticut. Mr.
Chasteney was graduated from Stevens
Institute of Technology in 1901 and has
been with the De Laval Steam Turbine
Company since the organization of the
American cnnip.iny. over 10 years ago.

SOCIETY NOTES

In connection with the New England
textile exhibition, to be held in the build-
ing of the Massachusetts Charitable Me-
chanics Association at Boston, com-
mencing .^pril 22, it is proposed to run a
power section under the auspices of the
New England Association of Commercial
Engineers.

The largest and most successful en-
tertainment and reception yet held by the
Universal Craftsmen Council of Engi-
neers, of Manhattan and vicinity, took
place on Friday evening, October 27, at
Lexington opera house. New York City.
An interesting vaudeville pertormancc
was followed oy a long dance program.
There were present many prominent per-
sons in the field "f operating engineering.

The annual bani^uct of the Engineers'
Blue Club, of .Icrscy City. N. J., was
held at Columbian hall, on Saturday
evening, October 28. Seated at the tables
were about two hundred members and
guests. .lohn }. Calahan was the toast-
master and introduced the following
speakers: F. L. Johnson. James R. Coe,
Charles F. X. O'Brien, Patrick Flannery.
Mayor H. O. Wiitpenn. Hon. Robert
Carey. George F. Tenant, president of
the board of education. Edward A. Mur-
phy. Ph.M.. John H Fooie and Frank
Hroaker. Between the speeches mem-
bers of the New York "Bunch" enter-
tained.

724

POWER

November 7, 1911

'J'herc is a furl her side to
this rckilion of tlie re-ader
to the ads that wasia't
touched ou by the man wlio
wrote the letter on the scrap-
book idea the other day.

* "Jt is yen' interesting,"
says another man, "if yon
have a file of the paper to compare the ads

ot firm 2o years ago and see the

difTerence between the machine made by
it then and now."

This idea of studying the development
and evolution of a machine bv following the
ads through successive years, is a mighty
interesting one. It is only another way of
following the growth of the firm itself and
observing how it has developed by ado]:»tion
of the latest methods and has worked step
by step to its present position. One can see,
in an ad. study like that, how one firm has
outrun another in the race for higher ef-
ficiency, and again how a certain firm came up
2o or 30 years ago with a product so good that it
has led the field ever since with few changes.
(Jne can see how new firms have started up
with new products, products that have done
away with losses and exasperating troubles
in the power plant which
you, maybe 20 years ago,
thought you would have to
l)ut up with till the end of
lime. But always ilic in-
teresting thing ui that studv
of firms' growth through
the ads is to see who has
tjc/u ahead. Being a little
better today than yester-
day, and a little better yes-
terday than the day before,
is the real winner of belief
in anything — man, firm or
machine.

'I'here is another side to
this comparison, though,
quite as important. It's the
difference in the ads them-
selves.

What this is you can no-
tice at once by putting a
page of 20-year-ago ads be-
side a page of today's.

Then the firms adverti.sed their oivn names.
Noiv they advertixc llieir goods.

vSelling by advertising the firm name only
was and is a left-over from the day when a
proclamation that a firm was "Caterer to
the King" was enough to sell its goods, no
matter what the quality of the goods dished
out by that same concern to the people who
weren't kings.

But today most firms talk about their
goods, not themselves. And this is because
there is more and more pressure on what the
machine, the boiler, the lubricant, the valve
themselves can do — no matter who makes
them.

All that change in the way of writing ads is
due to a study of yon, the
reader and buyer. The as-
.sociation with the quick,
vigorous force of the up-
todate power-plant paper
has put you on the alert
for things full of ideas.
Well, the only ad. worthy
to he coupled with such a
thuig is itself //(// of ideas
— it's the only kind of ad.
that will get your eye.

Look through Power's
Selling Section, and see.

^7<z-^

X'ol

NKW ^ORK, NOVEMBER 14. \'>]\

A thousand miles, or two or throe, according to
where you now happen to be, in the direction
of the setting sun lies the great and wonderful
golden State California and her no less great and
wonderful sisters of beyond the Big Di\'ide.

Horace Greeley, years ago, said, "Go W'est, young
man, go W'est." Many who followed his advice can
testify today as to the soundness of it. That many
are still following it is shown by the extraordinary-
growth in population of the whole Pacific Slope.
According to the latest census retiims, the State of
Washington grew from about 518,000 inhabitants
to over i,i4i,cx3<) during the years between i<)<k>
and 1910. Los Angeles went from about loi.ofx)
to about 3i9,cxx) during the same jieriod. Although
these are vivid examples, they are by no means excep-
tional and they serve to show how rapidly the Pacific
Coast is growing in importance.

With growth in population and the industries comes
growth in the various branches of operating engineering.
For the right type of man,
opportimities are abundant.

Conditifms in the far West UIS

differ considerably from
those in the eastern and
middle sections of the
country.

In the West water j)ower
is develo]K-d extensively.
F.ver>- big city is servc-d
with water-generated cur-
rent. "White coal" is the
rather descrii)tivc term ap-
plied to the water which
turns the generator wheels.

The majority of the
water-p(»wer stations are
located in the coimtry
miles from the cities they
serve and often in iiui-t
picturcstiue settings F-Vir
the man who enjovs the
invigorating air of the

country' along with the peace and quiet also tu be
found there . who enjoys puttering in his little garden
patch, employment as an operator at one of these
water-power stations is most congenial. The work is
not arduous and the eight-hour shift is the rule.
The pay is fair, considering the service required.

And for the ambitious man there is room ahead!
He may advance to chief operator, ff)reman, superin-
tendent of the division, etc.

In the steam-power plants crude oil is the chief form
of fuel employed. Crude oil is much easier and more
convenient to bum than coal; also, it can be burned
more efficiently. The engineer who operates a crude-
oil burning plant is spared many of the trials and
annoyances of the man who must bum coal. In
olTice-building plants oil makes a jjarticularly desirable
fuel. It is space-saving, convenient to handle and
store, dustless, and it can be burned without smoke,
soot or cinders.

The far West being a yoimg and growing coimtry,

most of its power ])lants

are new and well laid out.

Such jilants are a pleasure

-' :;!:;:J£E^-; to operate.

£^^=^ ... As a general thing, the eii-

'^-^' _ ■ gineer in the far West is giv-

— '•'— '_._- - en more res])onsibility and,

" "; " -^^5=^ as a conseqtience, receive^

greater respect than the man

in a corres])ou(ling jilant

in the Fast. Due to the

rapidly growing condition

of the section, newly

created •)|)porttmities are

more numerous.

The West is certainly a
gcHxl '-ertion for the man
who has ability and energ>-.
No one should make the
mistake, however, of think
ing that he can go out there
and fall into a soft snap
withotit "delivering the
g«w.ds ■

726

POWER

November 14, 191]

An Office Building Central Station

Several of the hotel and office build-
ings in the business district of Los
Angeles are equipped with miniature
central stations which furnish, in most
instances, light, heat, power and hydrau-
lic-elevator service to outside buildings
in the immediate vicinity. They are not
strictly "block" central stations because
in some cases buildings across the street,
and even as far off as a block and a half,
are furnished with the aforementioned
services.

The Walter P. Story building, on the
southeast corner of Sixth street and
Broadway, one of the handsomest and
most modern office structures in Los An-
leges, contains a plant which at present
serves a hotel, one other large office build-
ing, and a small store and office build-
ing. The capacity of the plant is suffi-
cient, however, to serve ten or a dozen
other buildings and it is expected that
ultimately it will. The Story building
is I 1 stories high and contains some 300

By A. R. Maujer

All office -bit ilding plant
iL'Iiich is laid otit lo furnish
outside buildings with cur-
rent, exhaust and live steam
and 2vater pressure for ele-
vator service, through tun-
nels under street and alley.

The fuel used is oil; it is
burned in a furnace ■which
preheats the air supply.

The elevator pumping
apparatus is a compound
Corliss high-duty pumping
engine of 2,800,000 gallons
capacity per 24 liours.

tance between the Story building and the
hotel is about 70 feet. The Los An-
geles Trust and Savings Bank Building,
which is supplied with exhaust steam for
heating and hot-water service, is 1 1
stories high and contains 255 rooms; the
distance between the Story building and
the bank building is about 105 feet.

The William Garland building, which
•is supplied with light, heat and power,
is three stories high and contains two
stores and 60 rooms. The distance be-
tween this building and the Story build-
ing is 100 feet.

These three buildings are connected
to the Story building by concrete-lined
tunnels in which the service pipes and
conduits are run.

A plan of the subbasement fioor of the
Story building, showing the arrangement
of the power-plant apparatus, is given
in Fig. I. At present the plant contains
three 150-horsepower horizontal return-
tubular boilers, 66 inches in diamster

Fic. 1. Plan anh ,^RRANCE.^tENT OF THE Story Building Power Plant

offices. There are four plunger hydrau-
lic passenger elevators and two freight
elevators of the same type. The Hay-
ward hotel, which is supplied with high-

pressure steam for cooking and exhaust
steam for heating and hot-water service,
is nine stories high and has accommoda-
tions for about 350 guests. The dis-

and 18 feet long. The shells are made
of '.-inch plate and have triple-riveted
butt seams. The heads are of 9/16-
inch plate. The steam drums are 36 by

November 14, 1911

P O W E R

727

72 inches in size and built of 's-inch
plate. Each boiler contains 98 tubes 3
inches in diameter and has 1555 square
feet of heating surface. The steam pres-

enters the arched passageway and mixes
from all sides with the jet of oil.

The construction of the burner, which
is of the internal mixing type, is shown

^^^Hl

^^^^^^^^^^^K^^ <

m

FiC. 2. BOILEK;. ANU .AU.\IL1.\R1ES

sure carried is 150 pounds per square
inch.

The boilers are fitted with furnaces
of special design, as shown in Fig. 3.
for preheating the air supply to the bur-
ners. Firebrick slabs are laid on the
entire grate surface, with the exception
of the last quarter, in a bed of fireclay
mortar and with joints of the same ma-
terial. Another course of slabs is car-
ried on loosely laid fireblocks which arc
about 3 inches high and arranged as In-
dicated in Fig. 3. At the front of the
furnace and above the upper course of
slabs a firebrick wall and arch extend'
across the furnace. In the center of this
wall an arched passageway extends for-
ward to within a short distance of the
boiler front. The burner extends into
this passageway to a point just back of
the rear face of the "dividing wall. All
openings around the firedoor and bur-
ner are stopped up so that no cold air
can get into the combustion chamber.
The air supply is admitted through the
ashpit doors and passes to the rear un-
der the grates, up through the grr.les

in Fig. 4. Steam enters at the top and
is discharged through a double set of jet
holes in tlie nozzle into the mixing bar-

vary in each case with the capacity of
the boiler, width of setting, etc.

That this furnace and burner are cap-
able of yielding satisfactory results is
shown by a recently conducted test. The
oil fired during this test had a heat value
of approximately 18,000 B.t.u. per
pound of oil as fired. The results
showed an average evaporation from and
at 212 degrees of 14.41 pounds of water
per pound of oil. This is equivalent to
an efficiency of about 77.7 per cent.

Fuel-oil System
The manner of storing the fuel oil
and supplying it to the burners departs
a little from average practice. The
storaee tanks, two in number, are 2
feet below the engine- and boiler-room
floor, or 32 feet below grade, and just
outside the building line and directly be-
neath the alley which runs back of the
building. Each tank is 6 feet 6 inches
in diameter, 22 feet long and has a capa-
city of about 550 gallons. The arrange-
ment of the tanks and piping is shown
diagrammatically in Fig. 5. An air pres-

-4S0

m-

f

irr:.]'^
JTf-l ,1.

Fig. 3. Design of Oil-burning Furnaces

Design

and then forward between the two
courses of firebrick slabs, circulating
around the supporting blocks and be-
ing heated as it goes by the almost in-
candescent roof slabs; at the front it

BlRNKR

rel, where it comes in contact with the
oil which is supplied from below. The
size and width of the jet. which is fish-
tail in shape, are determined by the
opening at the end of the burner and

sure of about 40 pounds per square i Mh
is on a tank when it is feeding to the
boilers.

The filling pipe extends up to the sur-
face of the alley, where it terminates in
a suitable plug. The oil is brought to
the building in tank wagons and filled by
gravity into either tank as desired. The
small pipes A serve to rid the tanks of
any water which may settle out of the
oil or be carried into the tanks by the
compressed air. The open discharge of
these pipes to a funnel in the floor
makes it possible to tell exactly when
all of the water has been drained out.

728

P O W E R

November 14, 1911

The oil receives no preliminary heat-
ing but goes to the burners at normal
temperature. In the burners it mixes
with the steam and an increase in its
temperature takes place before the oil
and steam leave the nozzles.

Boiler Auxiliaries

The boilers are fed by two Davidson
simplex pumps, 7 and 4 by 10 inches in
size. The feed water is pumped to the
boilers through a Keystone pressure fil-
ter from the hotwell in the bottom of a
closed heater, described by its designer
and builder, J. F. Connell, of Los Ange-
les, as an automatic receiver, steam
drum and water heater. This heater is
shown in the background of Fig. 2 and
its design and construction are illus-
trated in another portion of the paper.

The hot water for the house service
is supplied by this same heater. All of
the exhaust from the various engines
and pumps in the plant is led to the
heater and that which is not required
for heating the water passes on through
to the radiators distributed throughout
the several buildings served.

Generating Units

The present electrical generating
equipment is shown in Fig. 6. It con-
sists of two Weslinghouse three-wire
direct-current 125-250-voIt generators;
one has a rated capacity of 80 kilowatts
and the other 110 kilowatts.

The generators are direct driven by
horizontal tandem-compound center-

Fic. 5. Diagram of Oil-storage System
crank self-oiling engines built by the
Buffalo Forge Company.

During the summer months, because
of the light load, the low-pressure pis-
ton and eccentric of the small unit are
taken off and the steam is bypassed from
the high-pressure cylinder direct to the
exhaust. In this way, with the engine
running simple, the steam economy is
better under the light load than if both
cylinders were employed.

Elevator Pumps
There are two elevator pumps. The
main one is a 2,800,000-gallon cross-
compound Monarch-Corliss pumping en-

gine, built by the H. N. Strait Company
and shown in Fig. 7, which gives a view
from the low-pressure side. The steam
cylinders are 17 and 27 inches in diame-
ter with a 36-inch stroke; the water pis-
ton is 9 inches in diameter. This en-
gine has the capacity to furnish water
for the elevators not only in the Story

attached to the diaphragm forces up the
lever E which, acting through the
mechanism shown, shifts the knockoft-
block rods and shortens the high-pres-
sure cutoff. When the pressure in the
tanks falls, the knockoff blocks are
shifted in the opposite direction and the
cutoff is lengthened.

Fig. 6. The Electric Generators

building but in a half-dozen others as
well and it is expected that ultimately
that number of buildings will be served.
To prevent the engine from stalling on
dead center during a temporary period
of no load, it has been fitted with an
automatic bypass valve, controlled in the
manner illustrated diagrammatically in
Fig. 8, which also illustrates the hydro-
static governor for limiting the speed of

If the governor belt should break, the
weighted rider pulley F would cause the
cock G to open and admit air pressure to
the under side of the piston H, which
would rise and force the governor to
its highest position and thus cut off the
steam supply.

To prevent the engine from coming to
a full stop and consequently stalling on
dead center everv little while, the aux-

The Main Elrvator Pimp

the engine in accordance with the work
required.

The water pressure from the eleva-
tor tanks acts against the under side of
the diaphragm C and the pressure of
the spring D is brought to bear on the
upper side in the manner shown. As
the pressure in the tanks rises, the pin

iliary governor H is belted to the main
governor as shown. As the speed of the
engine decreases and the weights of
this governor fall, they operate through
suitable levers and links to open the
four-way valve / so as to admit the air
pressure supplied through the pipe /
to the under side of the piston in the

November 14, 1911

P O \v' F. R

729

bypass valve K. The pressure forces the ing. of the funnel which connects that Each day the assistant engineer fills

piston up and thereby opens the valve, building with the Story building plant, out a duplicate report form such as is
This bypass valve is piped so as to con- The tunnel is 3 feet 6 inches wide by shewn in Fig. 10. This is inspected and
nect the fore-and-aft suction chambers 6 feet high to the top of the arch. signed by the chief engineer, who re-

j tains one copy for reference and sends

the other copy to the office of the build-
ing.

Fig. 8. Arrancemewt of Auto.matic Governor and Bypass Valve

of the pump. With the valve open, some
water surges from one suction chamber
to the other— just enough to keep the
engine turning slowly when no water is
being discharged.

As soon as wafer is required in the
elevator tanks the engine speeds up a
bit and the weights of governor H rise.
This throws the four-way valve / into
the opposite position and thereby admits
air pressure to the top of the piston in
the bypass valve K and at the same time
allows the air beneath the piston to
escape through the exhaust pipe of the
four-way valve. The bypass valve then
closes and cuts off the flow of water be-
tween the suction chambers.

The auxiliary elevator pump, which is
used at night and on Sundavs and holi-
days, is a Davidson compound simplex,
controlled by a Ford governor. It is 14,
24 and 12 bv 20 inches in size. This
pump is shown in Fig. 0.

A general idea of the construction of
the service tunnels may be had from Fie.
II. This shows the entrance, in the I.os
Angeles Trust and Savings Bank build-

FiG. 10. Engineer's Report For.m

The oil burner and the furnace used
in this plant, and the fuel-oil storage and
supply system, as well as the hydro-
static governor and automatic bypass
valve on the pumping engine, were de-
signed and patented by John P. Proper,
the chief engineer of the building.

Fit.. 0. Tm AixiLiARv Ellvatok Pi mi-

730

P O \V E R

November 14, 19! 1

Notes on Crude Oil Fuel

By F. S. Wade

In California, where crude petroleum
in one form or another is used ex-

It is evident that the cheapest oil
for steam making is that having the low-
est degrees Baume, provided it is bought
by the gallon. It must be borne in mind,
however, that the very heavy oils, say

Fig. 11. Showing Construction of Tunnels

taining an excess of sulphur, is the most
economical for fuel purposes.

Great variations in the calorific value
of oils of apparently the same gravity
are often found and are due to water in
the oil. which in many cases is unde-
tected and not corrected for on account
of the rather general use of the so-
called "gasolene test" for water. This
test is made by mixing equal portions
of gasolene and oil and allowing the
mixture to stand 24 hours. At the end
of this time the percentage of water
can, supposedly, be read off on a scale
at the bottom of the test cylinder. As
a matter of fact this test rarely with
any oil, and almost never with the
heavier oils, reveals the full and cor-
rect amount of . water present. The
widespread specification of this test in
oil contracts is, therefore, greatly to be
regretted. In the experience of the
writer, water in crude oil can be deter-
mined satisfactorily only by the use of
a high-speed centrifugal testing ma-
chine or by distillation.

It is very often necessary to correct
the gravity or volume of fuel oil for
temperature. A standard temperature
of 50 degrees Fahrenheit is almost uni-
versally assumed and a deduction in
gravity of 0.1 degree Baume is gene-
rally made for each degree Fahrenheit
in excess of 60 degrees. Where the oil
temperature is below 60 degrees Fahren-
heit, a corresponding addition to the
obser\ed degrees Baume is made. This
correction figure, giving an expansion
factor of 0.0006 for each degree Fahren-
heit, was undoubtedly derived from the
lighter paraffin oils of Pennsylvania, but
is in no way correct for the asphaltic
oils of California.

Repeated experiment has proved that
the expansion factors of California oils be-

clusively as a steam-making fuel, the
question of the relative fuel value of
different grades is often raised. Much
confusion exists on this subject on ac-
count of the practice of stating the calo-
rific value of oils in terms of heat units
per pound, while the oil is bought and
paid for by the barrel of 42 gallons.
The accompanying table, made up
of analyses published by the California
State IVlining Bureau, together with some
analyses made by the writer, is in-
structive as showing the relation be-
tween the calorific value per pound and
the calorific value per pint of typical
California crude oils. All analyses are
stated for oil entirely free from moisture.
From the figures in the table it is
apparent that the heat units per pound
of oil increase, and the heat units per
pint of oil decrease, as the degrees
Baume grow higher. Also an exces-
sive quantity of sulphur (see samples
6 and 11) lessens the calorific value of
an oil to a considerable extent.

PROPERTIES OF CALIFORNI.V CRCDE OIL-<

District

Specific

Uravii.v

Pound.s

per
(lallon

Sulphur.
Percent.

B.t.u. per
Pound

No.

Uegieis;
Baume

B.i.u. per
Pint

1

Ncwhall

0 . 9880
0.9818
0.9756
0.9709
0 . 9669
0.9576
0 . 95.56
0.9472
0 . 9428
0.9396
0 . 9333
0.9327
0.9272
0.9150
0 9091
. 0.9061
0 8946
O.SSll
0 8766
0 8679
0 ,8.537

11.7
12.6
13.5
14.2
14.. S
16.2
16 , 5
17.8
18.5
19 0
20.0
20.1
21.0
23.0
24.0
24 5
26.5
28.9
29.7
31.3
34.0

S 24
S.19
S.14
8.10
8 07
7 99
7.97
7.90
7.87
7..S4
7 79
7.78
7.74
7.64
7 . 59
7.56
7.47
7.35
7.32
7.24
7.12

0.69
0.90
0.7.S
1.18
0.62
4 . 43

0 85
0.49
0.77

1 09
2.08
0.32
0 62
0.94
0.51
0.82
0.38
0.4S
0.72
0.38
0 41

18,481
18.655
18,612
18,623
18.700
18,464
18,787
18,830
18.724
18.794
18.664
19.087
18,894
19.046
19,016
19,018
19,224
19,165
19,161
19,330
19,399

19.030

19.093
18,933

1

18.906

<i

Ntnvliall

18,847
18.433

s

Lo;; .\!iKeles

NcwlKllT

18.724
18.6CL-
18.400

III

KulllTlOIl

18,418

11

18,168

IL'

1S„">60

i:i

Pm-mc

11

FulliTton

18,176

l."i
ifi
17

Fullcrton

I.. .V. I'uel Distillate

I'licntt'

18.030
17.973
17,937

IS
W

.Santa Paula

."^aiita Paula

17,612
17.515
17,494

L'l

17.267

11 or 12 degrees Baume, are extremely
viscous and very difficult to handle un-
less heated to at least 150 degrees
Fahrenheit. All things considered, an
oil of about 14 degrees Baume, not con-

tween 12 and 22 degrees Baume is sub-
stantially 0.0004 per degree Fahrenheit,
which gives a correction in gravity of 0.06
degrees Baume for each degree Fahren-
heit of the oil above or below 60 degrees.

November 14. 1911

POWER

Pioneer Power Plant of California

The recent announcement that the
Nevada power house, the pioneer gen-
erating plant of California, is to be dis-
mantled by its present owners, the
Pacific Gas and Electric Company, lends
particular interest to this small but
notable power station. Its name is
prominently connected with hydroelectric
generation and long-distance transmis-
sion development, and its period of in-
ception marks one of experimental work
which has contributed its quota of bene-
ficial results for advancement of like
enterprises.

Location and History

Located on the South fork of the Yuba
river, at the base of a V-shaped cation,
about half a mile below the ridge of a
chain of the Sierra mountains in Nevada
county, the Nevada power house —
familiarly known as the "Rome" power
plant, through the association of Romulus
R. Colgate with its founding — has been
in active 24-hour service from the year
1896 up to a recent period.

The proposed harnessing of the waters
of the Yuba river extends back to 1891,
■when Eugene J. de Sabla. Jr.. largely
identified with mining and numerous
power enterprises in the State, organized
the Nevada County Electric Power Com-
pany. The initial attempt to construct
a dam across the river for a ditch and
Tume system met with failure through a
flood in 1892. The succeeding venture,
in the summer of 1895, proved success-
ful, work being carried to completion the
latter part of the year. The dam, con-
structed of logs bolted to t]ie river bed-
rock, was 28 feet high, with a length
from bank to bank of the stream of 107
feet. The wood flume. 6 feet wide, 4'i
feet deep and about 3.3 miles long, was
bi!ilt at a gradient of 2fi feet to the mile,
and delivered a constant flow of approxi-
mately 58fX) miner's inches into a 48-
inch steel pipe. Thij intake diminishing,
through a distance of 300 feet and a
perpendicular descent to the plant of f90
feet, to 42 inches in diameter to increase
the energy of the jet, di. charged into a
steel receiver for delivery to the water-
wheels.

The difficulty experienced in getting
the machinery to the plant may be readily
imagined. From Colfax to Nevada City
the diminutive Nevada county narrow-
gage railway was used, and from this
point it was hauled by team to the ridge
overlooking the site, a distance of about
5 miles, and entirely up grade, a special
road being constructed. Each generator
weighed nearly six tons, and twelve-horse
teams were often required to gain this
suipinif of 1700 feet elevation. The ma-
chinery was lowered about 1300 feet to
the bottom of the gorge by means of

By L. R. W. Allison

This plant of 6oo and
finally 1200 kilowatis ca-
pacity has been in active 24-
hour service sin^ce 1896.
// was California's first
hydroelectric plant and is
now being dismantled.

log rollers, hawsers and cables. The en-
tire contract for dam. flume and power
plant was carried out by John Martin,
prominently associated with electric-
power development in California.

Construction and Equipment

The power plant. Fig. 1, is built on a
small, cleared-off ledge on the border of
the stream. The foundations are of
solid granite. The plant is connected to

air, automatic circuit-breakers, was
placed at the end of the power house.
The two-phase circuit was carried to
Grass valley, about 8 miles distant, on
poles 30 feet high, cut from the right-of-
v.ay for use. With connection about mid-
way of this distance, a branch line was
constructed to Nevada City. At these
two places substations were erected to
step down the voltage from 5500 to 2200
for mine operation, and to 550 and 1 10
volts for industrial and domestic pur-
poses.

The great "demands made upon the
little plant soon necessitated an enlarge-
ment of capacity, and in 1898 a reser-
voir was formed at Lake Vera, about 3
miles southeast of the station. This new
impounding system comprised about 42
acres of land, with an average depth of
52 feet. It was indirectly fed from the
large watershed of the Sierra mountains
north, and capable of a constant flow of
1000 miner's inches for a 30-day period.
The water was conveyed to the plant by

I. Extkrior Vie\x' op California's Pioni-kr Plant

a boarding house, on the opposite side
of the river, by a suspension bridge; the
hanging stairway, at the extreme right
of the illustration, leads froin the canon
to the Nevada City road. The installa-
tion consisted of two .VX)-kilowatt Stanley
generators of 1,13-cyclc. two-phase, in-
ductor type, operating at 40f) revolutions
per minute and generating at ,S.SO0 volts.
The two generators were each direct-con-
nected to three and four Pelton wheels
respectively, each walcrwhecl being 3
feel in diameter and having two noz-
zles. The maximum output of the plant
at full overload capacity was 800 kilo-
wafts.

The switchboard, operating with open-

ditch, flume and steel pipe, as in the
former instance. A break in the Lake
Vera dam in 1905 reduced its hight to
10 feet, and proportionally reduced the
capacity to a 10-day flow. The supply
from the Yuba river was accordingly
diminished to a normal flow of .1800
miner's inches. To provide for this aug-
mentation in water power, an addition
was erected to the plant. Fig. 1 shows
the original building at the left, the con-
nection between this and the larger por-
tion, constructed later, being easily dis-
tinguished. The pipe lines shown from
left to right, convey the Yuba river and
the Lake Vera flows, known as the low-
head and high-head respectively, both

732

POWER

November 14, 1911

being firmly anchored at the base of the
incline.

The later installation comprised two
additional Stanley generators, of the
same size and type as noted, driven with
Tutthill waterwheels Tnounted on the
same shaft as the low-hetid Pelton
wheels. All machines were operated in
parallel, the remodeled switchboard. Fig.
2, in the new addition of the plant being
equipped with Martin open-air switches.
With this total capacity, an average of
1200 kilowatts, the plant has been in
continuous service up to a few months
ago, being closed down through the
.Tbolishment of the 133-cycle type of gen-
erator by its owners.

Historical Interest

Great historical interest is attached to
the plant. Following the organization of
the Nevada County Electric Power Com-
pany, the Bay Counties Power Company
was formed in 1900 by the combination
of this company and the Yuba Power
Company. In 1903, the California Gas
and Electric Corporation was organized
to take over this and other systems,
while in 1906 the entire properties came
under the control of the Pacific Gas and
Electric Company, tying the little Nevada
power house in with a general system
covering an area of over 32,400 miles of
California territory, and serving two
thirds of the population of the State.

During its period of operation the sta-
tion has netted total earnings exceeding
S1,000,000. While larger and modern
generating plants now hold the center

of attraction, the "Rome" power house
is destined to hold first place in the his-
tory of hydroelectric-power development
in this country.

Fir,. 2. Remodeled Switchboard in New Addition of Pla.nt

A Commercial Water Power Problem

There is a small water-power de-
velopment in this country, dating back
over a hundred years, in w-hich var-
ious manufacturing plants hold a more
or less absolute ownership. In con-
nection with one of these plants, the
following questions came before the
writer for investigation:

1. The amount of water (flow) owned:

2. Its value for producing power;

3. Its equivalent lease value;

4. Its value for other purposes than
hydraulic power.

The mill had the right to use all water
that would flow through an aperture 6
inches high and 6 feet wide in the side
of the raceway (see Fig. 1 1, provided that
it returned this water to the tailrace at
a 30-foot lower level. The power com-
pany was obliged to maintain at all times
a headrace water level 30 inches or more
above the top of the aperture.

Flow

The simplest way of determining the
flow through the aperture was by actual
measurement of velocity; but a simple
analysis serves to nicely check and con-
firm experimental values. This analysis
depends upon the fundamental law of
falling bodies as expressed by the for-
mula:

By Prof. W. I). Ennis

The flow, available horse-
power, power valite and
lease value arc co)iipitleil
joy a s))iall water-power de-
'eelopiiieiif used in conjunc-
tion with a .^teaiu plant.

where,

v^ Velocity in feet per second;

g := Acceleration due to gravity, or
32.2;

h — Head in feet.
This may be applied to the water fall-
ing from the headrace level to the aper-
ture; but the difficulty is encountered
that h has one value, namely, 2'_. feet,
at the top of the aperture, and another
value, 3 feet, at its bottom. Nor is the
mean velocity that corresponding to a
mean head of 2.75 feet; for the velocity
varies, not directly as the head, but as
its square root. Therefore, the mean
velocity for computation of flow quan-
tity will be that corresponding to a head

greater than 2.75 feet and less than 3
feet. To find this mean velocity the fol-
lowing computatiors are made:

Top .

Point of Aperture

Veloc-
ity in
Head, Feet per
Feet Siecond
12.7

1 inch below top 2 . oS33 12 . 9

2 indies below top 2.6667

3 iiiibe,s below top 2.75

4 inches below top 2.8333

.') inches below top 2.9167

Hottom 3

These values may be plotted as in Fig.
2, the area abed divided by the dis-
tance dc, or if the ordinates between a
and h be averaged the true mean head
will be found, from which the mean
velocity may be read directly. This mean
head appears to be 2.78 feet, and the
corresponding velocity 13.37 feet, or.

1' ^= I 64.4 X 2.78= 13-37 /<"£< />«»■ second
The quantity of water delivered through
the aperture will be equal to the mean
velocity multiplied by the area, or

13.37 X 0.5 X 6 = 40.11 cubic feet
per second

The actual velocity is always less than
a computation of this sort indicates, and
the aperture stream may be regarded as
somewhat contracted from the full di-
mensions of the opening. Assuming the

November 14, 1911

POWER

733

cofficient of discharge under these condi-
tions to be 0.6, the probable flow is
to. 1 1 >' 0.6 = 24.07 cubic feet per second
At 60 degrees Fahrenheit, 1 cubic foot of
water weighs 62.37 pounds; hence, the
weight of water flowing is
24.07 :■ 62.37 = 1504 pounds per second
The ma.\imum head of this water is 30
feet, but at least 4 feet of this head will
be lost in the arrangement of the w^ater-
wheels; hence the theoretical available
energy is
1504 (30 — 4) — 39,120 foot-pounds
per second
or

39,120 ~ 550 = 71 horsepower
With 85 per cent, turbine efficiency.

. Head Rou Lerel

Fic. 1. Opening in Tank

71 / 0.85 = 60.3 horsepower
would be obtained.

PouER Value

The plant was already equipped with a
steam plant and with the waterwheel. It
burned about 5 pounds of coal per horse-
power-hour, which, at ,S2.75 per ton, gave
a fuel expense of

^^^ ^ ^ — 0.687s cent per honepnuer-hnur
2000

With a conservative allowance for labor
and supplies, the operating cost for
steam power was close to 1 cent per
horsepower-hour. The plant operated
steadily, and 60.3 horsepower could be
used about 6000 hours per year. To
provide this from the stertm plant would
have involved a cost of about
6000 / 60.3 / SO.Ol = .S3618 per year
on the basis adopted. If the plant had
had insufficient steam power, or if it
were a question of installing water-
wheels, the fixed charges would have re-
<)uired consideration. Thus, suppose ad-
ditional steam equipment to have been
necessary, involving a first cost of S40
per horsepower, on which the fixed
charges (interest, depreciation, taxes, in-
surance, etc..) were 15 per cent.; the
cost of 60.3 horsepower in steam would
have been increased by
S40 - 60.3 / 0.15 = .S361.80 per year
making the water power worth (if ignor-
ing the slight attendance necessary and
the sale value of the old waterwheel 1
S.W18 361.80 ,W79.80 per year
On this basis the value of ownership
In the water was that sum of money
which, invested, would yield an annual
income of S3979.80. Taking the equiva-

lent rate of interest on such an invest-
ment at 6 per cent., the sale value of the
water rights would be

$3979.80 ^ 0.06 = $66,330.

Lease Value

The plant could, of course, afford to
pay S3979.80 per year for the water if it
had not the necessary steam plant, or
S3618 per year if it had. These figures
are equivalent respectively to $1326.60
and $1206 per square foot of aperture
per year. Actual leases were being made
at much lower figures, because the water
power had to compete with more eco-
nomical steam plants, using 3 instead of

5 pounds of coal per horsepower-hour,
and perhaps running only 10 hours per
day. The question then arises, at what
price is the plant likely to be offered for
a deed of its water rights? Clearly not
$66,330, for a good steam plant could
not show even a 4 per cent, return on
such an investment to replace steam
power. Assuming the leases to be made
at S500 per square foot per year, on a

6 per cent, basis the value of the right
is then not over

$500 > 3 -^ 0.06 = $25,000.

Improvement of Plant

As a matter of fact, money might be
borrowed for improving the present steam
plant to such extent as to produce power
at a total expense, including fixed
charges, of 1 cent per horsepower-hour,
or S60 per year. This, however, would
involve an annual expenditure of S3618

course, returned to the tailrace. If 30
pounds of steam be used per horsepower-
hour, when running noncondensing. and
23'_. pounds when running condensing,
the saving in fuel due to condensing
would be

u.

, ;j L: :_,

: L

^^-^ 1

■" e.750(i
■gE.6667

i ' ^'^^

^"^

; ..^^

2.5(X)0

'\-fxr

1

— 3yi

100

2 1.6 />(> cent.

The value of the fuel saved per horse-
power-hour would then be

0.6875 X 0.216 = 0.1483 cent
The condensing-water consumption per
horsepower-hour would be

23' 2 X 30 = 705 pounds
The value of this water is then

0.1483 ^ 705 = 0.0002102 cent per
pound

Velocity, FeeT per Second

Fig. 2. Chart for Finding Mean
Velocity

for 60.3 horsepower, which the water-
wheel now avoids. It is difficult to
escape the conclusion that the poor econ-
omy of the present steam plant make?
the water right about $66,000; that this
is more than twice what It Is worth com-
mercially, and that the owners cannot
realize on the assets by putting in a bet-
ter steam plant and selling the water
rights.

Wathr for Condensing

It was suggested that the water might
he more valuable if used for condensing
the exhaust steam from the engines than
for power. Consider all of the water to
be thus available and that .V) pounds of
water will condense I pound of steam,
the condensed steam and water being, of

Fig. 3.

Casting Attached to Orifice
IN Present Case

Since the available flow is 1504 pounds
per second, the revenue from the water
used for condensing would be, per year,

(lo X 60 X 1S04 X o.txxj2it)2 X =

■ 100

5'i.'>.f)r)o

li would suffice to condense the steam
from an engine capacity of

1504 ■ 60 V 60 ^ 705 = 7660
horsepower
However, the following additional factors
should be considered:

1. The engine capacity, which was
under 2000 horsepower;

2. The first cost of the condensing
equipment;

3. Higher-priced attendance neces-
sary.

All of these being taken into account, it
appears that the best plan would be for
the plant to use as much of the water as
it can for condensing purposes, generat-
ing power with the remainder; for the
economy of the steam plant to be im-
proved by better operation; and for the
idea of disposing of the title to water
to be abandoned, at least until better
steam-plant economy has been attained.

Title versus Rental

The power company desiring 'to ac-
qtiirc ownership in all the water, and
offering a permanent lease in lieu there-
of, the plant might consent to deed Its
ownership to the power company In con-
sideration of the granting of a perpetual
prepaid lease; but since the former
would then he surrendering property for
a covenant, it would be safer to arrange
for payment by the power company of
the capitalized value of the lease rates —
say at 6 per cent, and S500 per squar?

734

POWER

November 14, 1911

l'€L^D=^^^i

foot per year- the power company would
pay to the mill

$500 ■ 3 -^ 0.06 r^ $25,000
in cash, and at the same time contract
to perpeutally furnish the present stream
of 3 square feet of cross-section at an
annual rental of $KS()0. If suitable
guarantees could be furnished, this
might be as satisfactory to the mill
as its present tenure, and it would
provide it with some additional working
capital. If the contracted lease is of
99 years' duration only, the payment
should e.xceed $25,000.

Increase of Flow

The conduit attached to the aperture
shown in Fig. 1 was not an open weir,
but an iron casting of the shape indi-
cated in Fig. 3. Many centuries back, it
is said, when Roman peasants drew
water for irrigation from the aqueducts,
they employed this same device. Now
proceeding to consider its effect, let a
tank of water be provided with a con-
\erging orifice, as in Fig. 4, the area at

.b

Fig. 4. Tank with Nozzle for Increas-
ing Flow

the outlet a being one square foot. The
flow of water, in cubic feet per second,
is, theoretically.

On =^ a V -^ a ] 2 gh
If a diverging mouthpiece b be at-
tached to a, the velocity at that point will
be greatly increased, the head equivalent
to the partial vacuum produced at the
contracted section being added to the
visible head. The velocity at the outlet
of b will become 1 -; tih. Let the area
at this outlet be 3 a. from which the flow
at b is

Oh =30 "".Vi = 3 a I ; </ h
nnd as this must equal the flow at a,

3 (! ] 2 qh ^^ a \ 2 <i h„
from which /!,/, the head at a, may be
found; this will, of course, exceed h. If
It equals 4 feet, then, theoretically, h„
would almost exceed the physically pos-
sible limit, becoming

4 V 3- = 36 feet.
Under these conditions, the flow of
water might be tripled, if there were no
excessive friction losses. In the pres-
ent case, with a maximum head of only
3 feet, the theoretical increase of flow-
Is even greater. The principle is that of
the "vena contracta," and the presence
of the iron casting of Fig. 3 invalidates

all of the foregoing calculations. Whether
the use of this device is legitimate, or
whether by long toleration the right to
employ it has been established, are other
questions. It is interesting to note, how-
ever, that it has been in service for many
years with the knowledge of all parties
concerned.

Largest Corliss Engine on

the Pacific Coa.st

A recent addition to the San Fran-
cisco, Oakland & San Jose Consolidated
Railway, Oakland, Cal., has just been
completed. This addition consists of a
4050-horsepower Hamilton Corliss en-

compound condensing type, having tail
rods on both the high- and low-pressure
sides; the low-pressure piston rod is
forged hollow. The cylinders are 42
and 86 inches in diameter by 60 inches
stroke. The steam pressure at the throt-
tle is 175 pounds per square inch and a
vacuum of 26 inches will be maintained.
The engine will run at 75 revolutions per
minute. It is expected that this engine
will consume 1 1 pounds of steam per
indicated horsepower per hour with con-
ditions existing in the Oakland station.
Both the high- and low-pressure valve
gears are operated by double eccentrics
and all steam and exhaust valves are
double ported. The valve gear is of the
new Hamilton Corliss gravity type, which

Low-pressure Cylinder OF 4050- horsepower Corliss Engine, Weighing 50 Tons

gine which is direct-coupled to a 2700-
kilowatt General Electric interpole gen-
erator; new boilers, feed pumps, con-
densers, etc., have also been installed.
The boilers will carry a steam pressure
of 200 pounds per square inch.

This engine is said to be the largest of
the Corliss type in service on the Pacific
coast. It is of the horizontal cross-

is guaranteed to operate at speeds up to
175 revolutions per minute. The flywheel
is of the built-up segment type, 22 feet
in diameter and weighs 200,000 pounds.
Some idea of the magnitude of this
engine can be had from the accompany-
ing illustration, which is that of the
low-pressure cylinder. It weighs 50 tons
and is made of semi-steel.

November 14, 1911

P O \X' E R

735

Novel Features of Mine Power System

Much attention has been attracted by
the new steam power plant of the Ray
Consolidated Copper Company at Hay-
den, Ariz., which supplies power for
operating the mines and the 10,000-ton
concentrating plant recently erected at
that place.

Four engines have been installed ( see
Fig. 1), the largest of the type ever
constructed. These are horizontal four-
cylinder triple-expansion Corliss engines,
with 28-inch high-pressure, 52-inch in-
termediate and two 54-inch low-pressure
cylinders, all having a common stroke of
48 inches. The low-pressure cylinders
are bolted directly to the frames, and
the high and intermediate cylinders are
placed tandem to the low-pressure cyl-
inders. The distance pieces between the
low-pressure and the high- and inter-
mediate-pressure cylinders are of heavy

By C. A. Tiipper

The ncic power plant of
the Ray Consolidated Cop-
per Company, at Hayden.
Ariz., contains four hori-
zontal fonr-cyliiider triple-
expansion engines, the larg-
est of their ivt>e ever con-
stmcted.

The hoist at ilie mine also
is of novel design.

guides, after being properly lined up,
are doweled in place so that they can be
removed when necessary to open the
cylinders and can be accurately put back

practice and has proved very successful.
Both the cylinders and frames are of
entirely new design, and the frame and
guides are made in one casting with a
lip cast around the base to catch any oil
which may run down the sides. One
of the most striking features of the
frame is the massive jaw which retains
the shells carrying the shaft. The bot-
tom shell is made circular in form so
that it will aline with the shaft under all
conditions.

The quarterboxes are adjustable with
•wedges, both fore and aft. adjusting
bolts being brought up through the top
of the cap and so arranged that the
quarterboxes can be taken up while the
engine is running at full speed.

The crosshead guide and crank are
entirely inclosed with steel oil guards
and the front is provided with wire-

Fir,. I, GiNERAL View of Enoini:';

construction and are split horizontally
so that, by taking out the tap bolts hold-
ing the distance pieces to the cylinders,
these parts can be removed, the inter-
mediate crosshead taken out, the low-
pressure cylinder head removed and the
low-pressure piston taken out. The tail

by replacing the taper dowel pins in their
respective holes.

The piston rods on these engines are
made unusually large and rigid so that
they practically carry the weight of the
pistons. This method of construction is
the same as that employed in i^s-cngine

screen doors, which prevent the oil be-
ing thrown out and at the same time
allow air to enter for circulation and
to assist in keeping the pins cool.

The full-load rating of each engine is
26.^1 horsepower when '■cceiving steam
at I7,S pounds gage and .V) to 1^ degrees

736

POWER

November 14. 1911

superheat; but they are designed to hati-
dle heavy overloads, as shown by the
fact that for over three months after
installation the first two engines ran
noncondensing and the load frequently

and is also transmitted at 45,000 volts to
the company's mines at Ray, 20 miles
distant. Here the features of the
power system center about the hoist-
ing plant.

2. M.AiN Hoist at Mine

a depth of 5000 feet at a speed of 300
feet per minute. The hoist is driven
through a rope drive by a 300-horse-
power three-phase, 440-voIt motor, the
latter fitted with a 44-inch pulley hav-
ing grooves turned for thirty-two 1-inch
ropes which drive a 13-foot pulley on
the pinion shaft of the main hois*.

The object of this design is to have the
hoist motor operate continuously in one
direction, while the drums may be
started, stopped or reversed. One cause
nf electric loss in hoists operating by
alternating-current motors is occasioned
by the starting of the motor, which when
the motor is large, becomes serious. It
is, therefore, desirable not to be obliged
to start the motor at each trip, since
when the motor is running idly the cur-
rent required by it is limited, so that the
peak losses are very materially reduced.
In this type of hoist the load is grad-
ually accelerated by applying a power-
ful clutch.

As shown in Figs. 2 and 3, the power
is transmitted from the large pulley to
the hoist by means of a bevel-gear driv-
ing and reversing system. The pinion
engages in two cast-steel, machined bevel
gears running in opposite directions.
Both these gears are loose on the shaft.

swung to 2500 kilowatts. Although the
normal rating of the generator is 1750
kilowatts with 80 per cent, power factor,
the engine carried this load with only
150 pounds steam pressure, which was
a remarkable performance for triple-ex-
pansion engine running noncondensing.

The flywheels are 26 feet in diameter,
weigh 55 tons each and are made from
steel castings on account of the high rim
speed corresponding to 100 revolutions
per minute.

Each engine drives a three-phase, 60-
cycle, 6600-volt generator excited at 120
volts from a 60-kilowatt direct-current
engine-driven generator. These units,
complete, were built and installed by the
Allis-Chalmers Company.

Steam is supplied by fourteen Heine
boilers of 513horsepower each, equipped
with Foster superheaters. The feed
water is delivered by four compound
Blake pumps, through three Foster feed-
water beaters. The hot water from the
condensing system is pumped to three
cooling towers, constructed on what is
known as the "Ray Consolidated sys-
tem," and thence returned to an
8,000,000-gallon reservoir which feeds
both the power plant and the mill. All
of the water circulated is handled by a
Nordberg triple-expansion pumping en-
gine of 10,000,000 gallons capacity per
24 hours. The original source of sup-
ply is the Gila river, where three motor-
driven pumps are installed.

Current from the generators is sup-
plied to motors operating machinery in
the ore-reduction mill, repair shops, etc..

Hohfinq Drums

. ,

1

'

. ^J\

n

:—

1 -,

u

80 Clutches,

Controller Lever

Fig. 3. Hoist and Driving Motor

The principal unit consists of a Well- while on the back of each is a friction

man-Seaver-Morgan hoist for lifting in ring with which the band-friction clutch

balance a net ore load of 12' j tons, a engages. The clutches are securely

skip of 8 tons and a rope of 3 tons from keyed to the intermediate shaft, and are

November 14. 1911

POWER

set by weights and released by the
operating cylinders. These cylinders
operate on compressed air taken from
the air mains supplying the mine, but
there is an auxiliarj- motor-driven air
compressor in the engine house which
works automatically in such manner that
when the air is up to 100 pounds current
is shut off from the motor, and when
the pressure drops to 80 pounds,
the motor is started again. Both of the
clutch-operating cylinders are worked by
a single lever on the operating platform
and are so connected that either clutch
may be thrown in at will; but both
clutches can never be in at the same
time, and one clutch must be wholly
thrown out before the other can be
thrown in. With the motor running 'con-
tinuously in one direction and connected
by means of the bevel gears to the hoist,
it is possible through the operation of
these clutches to start, stop and reverse
the hoist.

The intermediate shaft is extended

and fitted with a pinion which engages
in the main driving gear for the two
drums. This gear is approximately 16
feet in diameter. The drums are 12
feet in diameter and are grooved to carry
about 600 feet of I'j-inch hoisting
rope. The loose drum is fitted with a
powerful band- friction clutch of the
modified Lane type. This is of mas-
sive proportions, with a 12- foot driving
ring, and is built for a possible working
load of 50.000 pounds. Lifters are pro-
vided for equalizing the distance of the
bands from the clutch ring when the
clutch is released. Each drum has a
powerful post brake.

The brakes, as well ae the main clutch,
are each operated by means of a com-
bined air and oil cylinder fitted with a
floating valve gear under control of a
lever on the operator's platform. Dial
indicators are provided, one being driven
from each drum for showing the posi-
tion of the skip in the shaft.

The skips are not provided with safety

dogs or appliances, on account of the
extreme weight and bulkiness of such
equipment for a load of this magnitude,
but an overwinding device prevents the
skips from being carried into the
sheaves through any neglect on the part
of the operator. This device consists of
two limit switches, one for each skip,
so placed that when the skip is carried
beyond the highest point for dumping, it
will come in contact with an extended
lever fitted with a roller, which lever,
moving through an arc of 35 degrees,
disengages the contacts. These limit
switches are connected by wires to sole-
noids operating quick-opening valves in
the supply pipes to the air cylinders, so
that if the skip passes a given point in
the shaft, the solenoids come into action
and at once release the pressure from
the operating cylinders, allowing the
weights to apply both the powerful
brakes and throw out the clutches, bring-
ing the hoist at once to a stop without
the necessity of stopping the motor.

Flywheel Explosion, Farmington, Utah

On the afternoon of September 14. a
disastrous flywheel explosion occurred at
the Farmington plant of the Salt Lake &
Ogden Railway Company. Owing to lack
of definite information, however, the ac-
count of the accident has been withheld
until the present issue.

The plant, which was recently put in
operation, contains one 500-horsepower
and one 750-horsepower Allis-Chalniers
compound-condensing engine, each con-
nected through a belt drive to a 400-
kilowatt alternatinc-current senerator.

By William E. Piper

Due to the racing of the
cngDic. an 18-/00/ ftywheel
exploded, tearing holes
through the roof and the end
of the building. A o oiu:
leas miured.

on the shaft, as shown in Fig. 2. while
the other broke out at the bolt holes and
dropped into the basement. Fig. 3 shows
the wheelpit after the explosion. Frag-
ments of the rim and bolts were hurled
in all directions, some breaking through
the roof, as shown in Fig. 4, and an-
orher large piece passing through the
end of the building (see Fig. 5» and
continuing slightly upward until it en-
tered the side of a barn nearly 400 feet
distant; it then passed through the barn,
cut the other side 1 sec Fig. 6) and

I. Engine Rixim as It Appearkd iffuri
THF. Explosion

2. SHo\t INC. HiB OF Flywhi-rl ANn Damage
Done TO Engine

These units are shown in the general
view of the engine room. Fig. I. taken
a few days previous to the accident.
There arc two exciters, one motor-driven
through a belt and the other a steam-
driven direct-connected machine, shown

at the extreme right of Fig I. iusi be-
yond the large unit.

The engine of the latter unit had an
18-foot flywheel built up in four sec-
lions. This is the wheel which exploded.
TTic hub of one-half the wheel remained

landed at the base of the old apple tree,
shown in Fig. 7

The universal rod on the governor,
connecting the valve gears of the high-
and low-pressure cylinders, was broken
iind several of the pins on the valve gear

738

POWER

November 14, 1911

were bent; otherwise, little damage was
done to the engine. The receiver, how-
ever, was overturned and a hole made
in the oil separator; also, the pipes lead-
ing to the receiver from the high-pres-
sure cylinder and those leading from
the receiver to the low-pressure cylin-
der were broken in several places.

Just prior to the accident the engineer
was standing by the st^am-driven ex-
citer, which was being cut out, the ex-
citation load being thrown upon the
motor-driven exciter. It is supposed that
the latter failed to excite; thus the load

was entirely shut off. An instant later
the explosion occurred, causing the dam-
age illustrated.

When the engine first started to race
there were three or four men on the
roof of the building, but feeling the
vibration as the speed of the engine in-
creased, they started down just in time
to reach a place of safety. At the
switchboard in front of the engine there
were standing the manager's son, the
chief electrician and the substation op-
erator, but each escaped without in-
jury.

Half a Billion Toils of Coal

According to a recent bulletin of the
United States Geological Survey, the
combined production of anthracite and
bituminous coal and lignite for 1910
reached the unprecedented figure of 501,-
576,895 short tons, with a spot value of
.S629,529,745.

This is the first time in the history of
this country that its coal mines have
exceeded half a billion tons. This great
output, according to E. W. Parker, the
Survey's statistician, was attained in spite

Fic. 3. Wheel Pit

Fig. 4. Holes in Roof

Fig. 5. Hole in End of Biildlm,

^Hl

w^B^^

^^^^ K! nJ^lM^U

v^M

R»'^

%«(^|^^^^^|

Hbb

W m '*

^^IK^^Mlp

mH|

Ci^

•».

H^:' *

%

K

-'mmmmrim-miam'msM-^^ '~^^^k

Fig. 6. Barn after Piece of Rim Had Pa

lASE OF Tree

dropped on the engine and the governor
did not control the steam. By the time
the engineer had closed the throttle on
the exciter unit and had reached the
throttle of the runaway engine, the latter
had gained considerable speed. The
throttle valve had been newly packed and
-turned hard. Seeing the speed of the
engine increasing so rapidly, the engi-
neer deemed it advisable to protect him-
self and ran to safety before the steam

Before being installed in the present
plant the engine had been in service al-
most continuously for six or seven years
at another plant. It might be remarked
that in the former installation it was
found necessary only to give the throttle
wheel a spin, from which it would close
itself, and unless the attendant checked
it the valve often became set so that it
required the combined efforts of two men
to open it.

of the fact that most of the mines in
Illinois, Missouri, Kansas, Arkansas and
Oklahoma were closed for nearly six
months by strikes.

The largest increases in production
were in those States which benefited
from the idleness of the miners in the
Mississippi valley. As showing the larg-
est increase, Pennsylvania ranked first,
West Virginia, Ohio, Kentucky, Indiana
and .'Mabama following in order named.

November 14. 1911

P O W E R

739

Rewinding a Direct Current
Generator

By R. H. Fenkhausen

It is very probable that engineers lo-
cated near the larger electrical manu-
facturing centers do not realize their
advantage over those on the Pacific
coast. The Eastern engineer has only
to decide what special type of apparatus
is required for a given motor applica-
tion and delivery can usually be obtained
from the factory within a few days.

The great diversity of demands in the
electrical industry makes it impracticable
for the manufacturers to carry a full
stock of special apparatus in all the
large cities, so that the Western engi-
neer is usually forced to adapt to his
needs the standard apparatus available
in the local stock, or else wait several
weeks for delivery from the factory.

It frequently happens that special
electrical processes must be placed in
operation at the earliest possible date,
and instead of ordering the apparatus
best suited to the process in hand, the
designing engineer must first ascertain
what machinery is available locally, and
design his other apparatus to suit the
speed and other characteristics of these
machines. It is this handicap of 'dis-
tance which forces the Western engineer
to adopt some of the peculiar engineer-
ing expedients which often startle the
Eastern visitor to the Pacific coast. The
fact that efficiency is sometimes sacri-
ficed should not detract from the ingen-
uity of the application, because it is
hardly necessary to call attention to the
careful study required before the avail-
able apparatus can be made to give even
moderately satisfactory results.

Lack of suitable machinery often com-
pels the engineer to rebuild a standard
machine, sometimes at a cost greater
than that of a new machine. Rebuilt
machines are quite common in the West,
and they often puzzle the original man-
ufacturers from whom repair parts are
ordered after the machine has changed
hands. The new owner does not al-
ways recognize the special character of
the machine and orders repairs as per
the serial number on the nameplatc,
occasionally with startling results.

The manufacturers themselves are
••omcfimcs guilty in this respect, as the
writer found to his inconvenience on two
occasions. In one instance several mo-
tors of a given type were ordered and

supplied from local stock by the manu-
facturers, nothing being said about the
machines having been rewound in their
local repair shop. The nameplates had
been changed for new ones but the fac-

Fic. I. Various Shapes into Which
Windings Were Bent

tory serial number was stamped on the
new plate, with the result that a new
set of coils ordered some years later
were not suited to the machine, and the
truth only came out after much wrang-
ling and loss of time.

A rather unusual problem of rewind-
ing came before the writer, last year. A
65-volt. 450-ampere. direct-current gen-

\ olt motor frame already on hand could
be altered. The on'.y doubtful point was
the ability of the commutator and
brushes to carry six times their rated
current for 15-minute periods, but it
was figured ^at this could be accom-
plished by using wider and thicker
brushes and directing a current of air
from an electric fan onto the commuta-
tor.

The original winding was of the pro-
j^ressive-wave type, with 94 coils (one
idle) arranged two per slot and connected
to a 93-bar commutator. Each coil con-
sisted of two turns of No. 10 wire, the
two turns being in parallel.

The new winding was also of ,the
progressive-wave type, but had only
47 coils, one per slot, and required a
47-bar commutator. Each coil consisted
of one turn of No. 2 wire. It was
intended that copper strap coils be used,
but a canvass of the local market re-
vealed nothing suitable; even the No.
2 wire finally adopted was bare,
hard-drawn trolley wire which had been
left over from the cranes and had to be
annealed before using.

The various steps in the process of
bending the coils are shown in Fig. I.
and the special tools used are illustrated
in Fig. 2.

The wire was first bent into two con-
centric U-shaped loops, shown crossed
at the left of Fig. I. These loops were

■^

Tools Used in Bi NniNO WiNniNcs

erator with a speed of 1120 revolutions
per minute was required at short notice
for some special electrolytic research
work, and no standard llO-volt machine
nl the proper characteristics was available
locally. A 4.'S0-ampere, llO-voIt machine
could have been run at reduced speed
and separately excited, but there was
no such machine to be had.

After some preliminary calculation it
was decided that a 20-horsepowcr, 220.

formed by bending the wire around the
forms shown at a and h. Fig. 2, and
squeezing in a vise. The hooked ends
of the forms held the wire in close con-
tact with the form and prevented dis-
tortion of the loops. The sizes of the
two loops were such as to permit the
insertion of cotton insulation between
them.

The two loops were then "nested,"
placed in the tool shown at r and pulled

740

POWER

November 14, 1911

out into the shape shown at the top of
Fig. 1, the slanting surfaces of the too!
being used to give the proper angle to
the coils.

The tool d was ne.\t clamped between
the jaws of a vise and the coils bent
to conform to the wooden templet e,
as shown in the center of Fig. 1, each
bend being marked off from the templet
in turn. As the end connections of the
coil had to span half the circumference
of the armature, it was necessary to

Ar'«r«

,.;et*

'f^^:ZM:^\^in/ /A

Fig. 3. Original and Final Method of
Attaching Windings to Com.mutator

bend them approximately to the form of
a semicircle. A hardwood saddle /
was cut out to the proper radius on a
handsaw and the end connections were
shaped to it with a fiber mallet, after
which cotton sleeving was slipped over
each coil and given a coat of varnish
to hold it in contact with the copper.

The original winding had a cross-
section of

4 X 10,404 = 41,616 circular mils
whereas the cross-section of the new
winding was

4 X 66,564 = 266,256 circular mils
It will be noted that the amperage
capacity is six times as great, while
the voltage is decreased to only one-
quarter of its original value, which is
equivalent to a 50 per cent, increase in
capacity for the same speed. This in-
creased capacity was possible on ac-
count of the extra copper, in the space
formerly occupied by the insulation be-
tween turns. Had rectangular copper
been available, 20 per cent, greater
capacity would have been possible.

Commutator Changes

The most difficult problem was the
commutator, as only 47 bars were re-
quired instead of 93, and the necks were
too thin to slot for No. 2 wire, even
had it been possible to bend the wire
down to the bars. Hence the method
shown in Fig. 3 was adopted. The com-
mutator was dismantled and an extra bar
was made of busbar copper and care-
fully filed to the exact shape. Each mica
segment was then slightly skinned until
enough mica had been removed to make
room for the new bar. As the latter
was only 0.25 inch thick and there were
94 mica segments, it was necessary only
to remove an average of about 2J< mils
from each segment. The new bar was

made with parallel sides and not tapered
like the other, because it replaced mica
which was parallel.

The commutator was then reassembled
with the copper and mica segments in
pairs, the copper surfaces between the
bars of each pair being rubbed to a
perfect surface on fine sandpaper glued
to a true surface plate.

Radial necks were made from 1/16x1-
inch copper and pressed into shape with
the tool g, Fig. 2. This tool was also
drilled to serve as a jig for drilling the
rivet holes in the necks. The copper
strips were riveted back to back in pairs
and after being tinned all over were
sweated into the original wire slots in
each pair of bars, as shown in Fig. 3.
making a soldered connection between
each pair of bars through the neck, in
addition to the contact between the bars
themselves. As the r.^cks came up flush
with the outside of the core, the coils
came straight out to the necks, and, being
on a much larger circle, left ample room
between necks for ventilation and in-
sulation.

Insulating cells were placed in the
armature slots, and the coils were in-
serted and soldered, after which the

amperes were carried with ease and 450
amperes could be carried for about 30
minutes by using an electric fan to cool
the commutator. There was no percep-
tible sparking, but the heating of the
commutator became so great after a
30-minute run as to almost melt the
leads out of the bars.

As 15 minutes at 450 amperes was
all that was required, no trouble was
encountered and although it cost con-
siderable money to rebuild the machine,
the cost was only a fraction of the
probable loss had it been necessary tn
wait for a new machine from the
factory.

In large bar-wound machines having
conductors over H inch thick it is cus-
tomary to use several thin bars, con-
nected in parallel at the commutator, but
insulated from one another throughoui
their length, to cut down the eddy-cur-
rent loss in the copper. It was feared
that No. 2 wire would give trouble
from this source when used on a com-
paratively small armature such as the
one under consideration, but although the
eddy-current loss was present as shown
by the no-load tests of the machine, it
did not seriously affect the capacity and

Fig. 4. Machine as It Appeared after Rewinding

bonding w^ires were replaced and the
commutator turned.

Owing to the large amount of metal
to be heated at the point where the
leads were soldered to the commutator
necks, it was necessary to use a heavy
electric soldering iron, with a tip slotted
to fit the neck, as shown at h, Fig. 2.

The original brushes were ;i inch, but
the doubled bars allowed the use of a
1-inch brush, and in making the holders
for the new brushes the width was in-
creased about 25 per cent., as the full
width of the commutator was not covered
by the old brushes.

When the machine was finally com-
pleted, the field was separately excited
from the 220-volt power circuit and
the machine was given a full-load test
together with its driving motor. The
results excelled the expectations, as 300

the machine was in daily use up to the
end of the writer's connection with the
company for which it was designed.

Fig. 4 shows the machine coupled to
its driving motor, and it will be seen
that there is nothing unusual about the
appearance of the installation.

A factor which militates against the
success of Chinese industrial undertak-
ings is their dislike of employing foreign
engineers. The Chinese are quick to
see the industrial and commercial ad-
vantages in the Western way of doing
things, but, as in plants and factories,
they go to great expense in erecting an
uptodate plant and installing machiner\-;
then they discharge the foreign expert
almost as soon as the machinery- can be
started and when anything goes wrong
they are helpless.

November 14. 1911

LETTERS

Mr. Ropeter's Comment on
Mr. Edge's Wiring

In the October 10 number, Mr. Ropeter
criticizes my article on "Wiring Pointers"
in which one snap switch is shown con-
trolling eight lamps, saying that the fire
underwriters will not allow more than
three lamps on one snap switch. This
statement really has no meaning, be-
cause the underwriters' requirements are
expressed in amperes or watts, and not
lamps; it is possible to put one lamp in
a circuit that will require as much cur-
rent as eight regular lamps.

Further, I would refer him to the fol-
lowing statement on page 40 of the
underwriters' rules:

"Up to 250 volts and 30 amperes ap-
proved indicating snap switches are sug-
gested in preference to knife switches

9^Sv,itch

0 0 0 0 0 0 O Oi

<m^^"^mmmmmmmmmmmmm'»z;:

l)s./.

^

0 (^ 0 o ;> 0 (^

i

mf""""" " "!

-5^', 0 6 ■

Fig. 5

on lighting circuits." This makes if pos-
sible to control one hundred and twenty
Ki-candlepower lamps with one snap
switch. Of course, this means a double-
pole snap switch, but nevertheless it is
a snap switch. Directly beneath the
suggestion quoted is the rule: "Single-
pole switches may be used in two-wire
circuits supplying not more than 660
watts." This rule enables one to control
twelve Irt-candlepower lamps with one
single-pole snap switch.

The connection of the two-light cir-
cuit in Figs. 4 and 5 is a mistake in
the drawing: the circuit should start from
inside the fuse block, so as to be pro-
tected by the fuses.

Regarding the paragraph on grounding
conduit being restricted and vague. I
would say that this paragraph was cut
short purposely, because I look it. for

P O W F R

granted that all engineers understood
such a simple thing as grounding a pipe
and if they did not they could easily find
cut by referring to the fire-insurance
code of rules and regulations.

Walter C. Edge.
Philadelphia, Penn.

Referring to Mr. Ropeter's criticism
in the October 10 issue of Mr. Edge's
wiring diagrams, I beg to say that the
underwriters allow single-pole switches
to control circuits carrying 660 watts or
less, and Mr. Edge's circuit had but
eight lamps which would require only
448 watts, with carbon filaments, and
much less with tungsten. Moreover, on
page 40, section 22 (b) of the "Under-
writers' Rules," it is suggested that up
to 250 volts and 30 amperes improved
indicating-snap switches should be used
in preference to knife switches on light-
ing circuits. As to the two-light circuit
without fuses, that would be all right
providing the size of the wire to the
two lamps was the same size as that in
the other circuit, and fused rosettes were
used, which could be done because No.
14 wire would be large enough for all
requirements in this case.

William T. Garlitz.
McKees Rocks, Penn.

Failure ot a CJenerator Due to
a Swinging Open Circuit

Recently the writer had an experience
with an alternating-current generator that
may prove of interest to others because
of the unusual and baffling conditions
existing, which obscured the real trouble
and had everyone guessing for a while.

The machine was a little alternator de-
livering single-phase current at 110 volts
.ind 60 cycles. It was an old type of ma-
chine with a stationary field magnet and
a revolving armature. The wires con-
necting the winding to the collector rings
were soldered to lugs on the back edges
of the rings.

The machine refused to generate on
several occasions before the trouble was
located, and the electrician reported that
each time the machine had refused to
show any voltage, after tinkering with
it a while it had "built up" all right
without any apparent cause. He also
said that he had tested the armature and
field circuits with a magneto and they
had tested out entirely clear of grounds
and open circuits.

Matters kept getting worse until one
day the generator refused to build up
its voltage and the usual tinkering failed
to produce any results. The writer and
the electrician went over all the connec-
tions and tested all the circuits, includ-
ing the armature, with the magneto out-
fit. Everything was apparently all right.

741

but the alternator still refused to gen-
erate any voltage.

After working around for half an hour
we finally started the machine up, dis-
connected the outside circuit leads and
attempted to ring through the armature
direct from the two collector rings, but
were unable to get a ring from the mag-
neto. This could only be due to an open
circuit, but we had just tested the arma-
ture standing still and the rfiagneto had
rung through all right. We shut the
machine down and tested the armature
again, standing still; the magneto rang
through all right. We then started it up
again, and the armature tested open.
This, of course, could be due only to a
swinging open circuit which swung open
when the armature was mnning and
closed when it stopped. Investigation
with this in view soon disclosed the
fact that the armature lead to the lug
on one of the collector rings was loose.
When the armature was standing still,
this lead made contact with the lug but
when the armature was rotating, centrifu-
gal force caused the lead to fly away
from the lug and open the circuit. After
the lead was resoldered to the lugs the
generator operated perfectly.

H. M. Nichols.

Kenyon, R. I.

Niagara and Victoria

What is the true comparison between
ihe power of Niagara and the Victoria
falls in South Africa? The answer is
that the flow at Niagara varies between
(i2.000,000 and 104,000,000 gallons per
minute; that at Victoria is as low as
about 5,000.000 gallons in August.

The mean available drop at Niagara is
160 feet and at Victoria 380 feet. Hence,
while the minimum Niagara flow repre-
sents about 3.000,000 horsepower, the
Victoria flow in August represents only
5*^0,000 horsepower, and, accepting the
statements of local authorities that in
November the flow at Victoria drops to
only 2,500.000 gallons per minute, the
minimum horsepower there can be onh
about one-tenth of Niagara's minimum.
The maximum of Victoria is not given.
Scicntitic American.

Work on the construction of a power
plant at Ihe Yakt falls, 20 miles north-
west of Libby, Mont., is to start at once,
according to J. H. Ehlers, of Spokane,
who recently visited Libby on business
in connection with the beginning of op-
erations on the project by the Milwaukee
Power Company. The plans and speci-
fications for the plant have been com-
pleted at a cost of SIO.OOO. It is the in-
tention to develop 3400 horsepower in
two units of 1700 horsepower each. A
portion of the electric power generated
will be used by the Lincoln Gold Min-
ing Company, which owns the .Sylvanite
mines.

P O "«' E R

November 14, 1911 •

Flywheel \\ rctk at Ha^^ert}-
Shoe Factory

During the forenoon of October 24,
two 72-inch flywheels of a 35-brake-
horsepower producer-gas engine, belong-
ing to the Hagerty shoe factory, of
Washington Court House, O., separated,
badly injuring the engine operator and
wrecking the engine, but causing very
little damage otherwise.

The unit is of the four-stroke-cycle
type with poppet inlet and exhaust valves
and auxiliary exhaust port, which is un-
covered by the piston on reaching the
crank end of the stroke. The engine is
a 14x24-inch with forged crank shaft 5
inches in diameter and crank pin 6 inches
in diameter by 5 inches long. To the
left flywheel (estimated weight about
20(X1 pounds), was bolted the driving
pulley for belt connection with a clutch
pulley on the line shaft at the rear of
the engine, shown in Fig. 2.

The unit, which had been in service
about four years, was installed to op-
erate on producer gas, developing .35
brake horsepower at 190 revolutions per
minute, and at the time of the accident
was running on a mixture of natural and
producer gas.

On the morning of the accident the
engine was started at about 6 a.m. and
lan smoothly until about 8:30 a.m., when
those working near heard an unusual
sound like that of scraping or grinding
going on in the engine. There was no
indication of an increase in speed on
the part of the engine. The operator
had just stepped from the producer room
to a position near the cylinder head,
when the flywheel on the left side let go,
immediately followed by the wheel on
the right. The engineer had no recol-
lection of just what happened after step-
ping through the producer-room door,
but when found he was lying across
the air-supply line with a rim section
of the right wheel, weighing about 800
pounds, resting upon him. This rim sec-
tion, shown at the left in Fig. 1, was
of about 160 degrees and clear of arms.
It struck the basement wall, causing
some damage, and then rebounded, catch-
ing the engineer. In its flight it tore away
the producer- and natural-gas connec-
tions and the air-supply line, destroying
the governor mechanism and displacing
the inlet-valve box as shown in Fig. 1.
A section of the left-hand flywheel tore
away the double-exhaust connection
which ran horizontally from the engine
cylinder and connected to a vertical ex-

haust line, shown in Fig. 2. Some part
of this wheel also struck the clutch pul-
ley on the line shaft, knocking out a
section of its rim.

A 12x1 2-inch wooden girder, located
just to the front of the engine, of 15-foot

increased by :n inch for the belt-pulley
side and '4 inch for the right-hand side.
The enlargement of the keyway may be
>een in Fig. 1. This change in dimension
of the keyway indicated a movement for-
ward on the shaft by the flywheels, plac-
ing the keys in shear and the hubs in
tension, this movement being greater on
the right side than on the left, due to
the pull of the driving belt.

With the exception of the keyways,
the crank shaft, the crank pin, connecting
rod, main bearings, bed and cylinder
seemed to be in good condition.

.'\n examination of the piston and rings
disclosed several new indentations on
the face of the piston, a small section

Fic. 1. Inlet-valve Box Displaced and Both Flywheels S.mashed

span and supporting the floor above, was
struck by each flywheel, displacing it 4
inches horizontally.

Each wheel rim broke into three pieces
and of the 12 arms belonging to the two
wheels, only one remained connected to
a wheel-rim section. Each of tfie hubs,
which broke into several pieces, fractured
parallel with the shaft and in each case
one of the fractures followed the keyway.

Each keyway of the shaft was carried
fonvard in the direction of motion so
that the metal of the shaft was raised
and the width of the keyway at the top

of metal broken from the edge of the
piston face exposing the first ring, and
about 2 inches broken from the end of
the first ring. This piston-ring end with
several small pieces of cast iron were
found in the cylinder crowded up against
the cylinder head. The ring portion
showed signs of having been under com-
pression and shear, and, therefore, these
facts with others cited above would in-
dicate that in some way this piece of
ring on breaking away got into the clear-
ance space, jammed between the piston
and .cylinder head and produced suffi-

November 14, 1911

POWER

743

cient sudden retardation of motion of acid which attacked the metal surfaces

the crank shaft to compel the flywheels,
their rims weighing about 1800 pounds
and having a linear velocity of about
3500 feet per minute, to break and to be
thrown from the shaft.

and also destroyed lubrication entirely,
allowing the mechanical wear to proceed
at an extremely rapid rate. Leaky cyl-
inder-head packing will produce exactly
the same results.

Fig. 2. Crank End of Wrecked Engine

Effects of Sulphur in Fuel Oil

or Gas

By Oi af Olafsen

Operating engineers have, no doubt, at
times been puzzled to account for an oc-
casional case of extremely rapid deteriora-
tion of pistons, piston rings and cylinder
bores of whatever types of internal-com-
bustion engine they may operate. The
writer has often been called out to In-
vestigate such difficulties, sometimes only
because the operator had discovered that
the lubricating oil worked out of the open
end of the cylinder In the form of a
rusty sludge which was not unctuous In
the least and had no "body."

One case of particular Interest was that
of a double-acting horizontal engine In
which one cylinder wore more than '4
of an Inch In diameter in about three
weeks. Another case was that of a smaller
single-acting engine with a trunk piston
In which the cylinder was enlarged 0.025
of an Inch In about three weeks, although
the engine was a new one.

The answer Is simple: The cylinder
walls In both cases were slightly porous
and the cooling wafer oozed through very
slowly but rapidly enough to combine
with the sulphur in the fuel gas or the
sulphur dioxide In the products of com-
bustion, forming sulphurous or sulphuric

Another part which is affected serious-
ly by this cause Is the piston rod of a
double-acting engine. Should a rod re-
ceive any water splash from the water-
discharge tubes which are attached to the
shoes, it will soon be corroded and the
wear will become quite serious, often
beyond the belief of those who have not
had the experience.

A similar trouble is caused by cooling
the pistons and rods of double-acting
engines with water which is at too low a
temperature. If the operator runs cold
water through the rods they will "sweat"
and the moisture will combine with the
sulphur in the combustion products and
produce what seems to be a mysterious
cause of extremely rapid rod wear.*

Still another Instance of this harmful
Influence Is that of engines provided with
splash lubrication In closed crank cases.
Some of these engines are operated with
a large amount of water In the crank
case, the oil floating on the surface of
the water, and when the engine is In op-
eration they mix in a sort of emulsion
which lubricates the reciprocating parts.

There Is always more or less "blow"
past the piston rings into the crank case
during operation; consequently, the crank
case Is filled with oil and water vapor and

•Thio pxplnnntlon of nlinnrmnl ro<l wonr
vrtm fnii:frf*"tf>rl fllnn by K. B. l><>ot. alKiiit (wo

products of combustion which have blown
past the piston. This is the best possible
condition for effecting the combination of
water and sulphur dioxide and acid is
soon formed; the crank shaft, especially
at the finished bearings, is attacked; the
finished parts become blackened and
often eaten away to a considerable depth.
For this reason, it is unsafe and inde-
fensibly bad practice to use water along
with the oil in the crank case of any in-
ternal-combustion engine using a fuel
« hich contains sulphur.

■Many Diesel engines are operated with
water in the crank case but the operators
are cautioned to have the fuel oil ex-
amined for sulphur and the use of water
is prohibited if the fuel contains more
than one-half of 1 per cent, of sulphur
compounds.

City or illuminating gas contains con-
siderable sulphur. Although the presence
of hydrogen sulphite in city gas is ex-
plicity prohibited by law. all illuminating
gases are allowed to contain from 150 to
300 grains of sulphur compounds per
1000 cubic feet and as the difficulty and
Ldst of absolutely removing the sulphur
from illuminatinggas are great, it Ismoral-
ly certain that in practice the legal limit
will be reached if not exceeded.

The natural gas of certain districts is
free from sulphur but it is said that old
wells, either gas or oil, give off a more
sulphurous product than newly opened
wells and it is well, therefore, to have
the fuel tested for sulphur from time to
time. The fact that a well once gave oil
of a low sulphur content docs not give
any indication of how long it will con-
tinue to do so. Certain oil companies
will furnish what they call a "desulphur-
ized" fuel oil.

Producer gas, blast-furnace gas, or. In
fact, any gas which is made by either
a dry-distillation or partial-combustion
process or both, is sure to contain enough
sulphur to be troublesome in case of a
water leak or with water in the crank
case.

The Grille C'rucle Oil Gas
Producer

There was installed some time ago In
the Fry pumping plant of the Union
Hollywood Water Company (Los Ange-
les, Cal.) a gas producer using crude
oil as "fuel" and operating on a prin-
ciple different from that which usually
forms the basis of operation of oil-gas
producers. The oil Is atomized In the
upper part of the generator by means of
a steam sprav and there subjected to
partial combustion. The products of this
partial combustion pass downward
through a bed of incandescent coke in
the bottom of the generator and the
heavy hydrocarbons arc thereby "broken
up," the tarry content Is "fixed." and
the portion of carbon which would ordi-

744

POWER

November 14, 1911

narily pass out as lampblack is deposited
on the coke bed and replenishes the bed,
partly making good the reduction due
to gasification of the coke.

The accompanying sectional elevation
of the generator and scrubber serves to

the quality of the gas and the rate of
production. The coke bed tends to re-
duce the extent of such effects by serv-
ing as reserve fuel. Morever, such im-
purities as get into the generator, as well
as the heavy hydrocarbons which ordi-

Grine Crude-oil Gas Producer

indicate the simple construction of the
former. The generator is about 4^
feet in diameter, inside, and 8 feet high.
The coke bed in the bottom is maintained
at a depth of between 3 and 4 feet.
The reduction of the bed by gasification
is very slow; the outfit under discus-
sion supplies gas to a 100-horsepower
engine running at practically full load,
24 hours a day, and the replenishment of
the coke bed requires about 800 to 900
pounds a month — approximately one-
eightieth of a pound per brake horse-
power-hour.

The provision of this bed of incandes-
cent coke fulfils several conditions
■which are of importance in the gasifica-
tion of crude oil. Commercial crude
petroleum contains a small amount of
earthy matter which is likely to be de-
posited in small openings and change the
rate of fuel delivery, thereby affecting

narily give so much trouble in the form
of tar or lampblack, or both, are stopped
by the coke bed. The heavy hydrocar-
bons are broken up, as previously stated,
by the heat of the incandescent coke,
the lighter portions being turned into
fixed gases and the solid carbon
liberated by the cracking process being
deposited .on the coke and subsequently

gasified slowly instead of passing out
as lampblack.

The gas is scrubbed and cooled in an
ordinary tower scrubber containing
water sprays and trays covened with
coke, brick or other material for giving
surface. Air for partial combustion is
supplied at a low pressure by a positive
blower, and oil is pumped from the reser-
voir and delivered to the burner under
pressure by a small rotary pump. We
are informed that the operation of the
apparatus is simple and that no burning-
out periods or periodic shutdowns for
cleaning out are required.

The plant has been in operation
nearly a year, the engine driving an
Ingersoll-Rand air compressor which
compresses air up to about 85 pounds
gage pressure for pumping water by
means of air lifts. The water, after be-
ing pumped to the surface by the air
lifts, runs into a large cistern from which
it is taken by a Dow duplex pump, also
driven by the gas engine, and forced into
the city mains.

The producer was designed by H. A.
Crine, engineer of the Gas Power Ma-
chinery Company, Los Angeles, and Mr.
Grine informs us that the Fry plant,
using crude oil at 95 cents per bar-
rel, or 2.3 cents per gallon, develops
the same amount of power per gallon of
crude oil that the ordinary distillate en-
gine develops per gallon of distillate,
which costs 7 cents per gallon in the
same locality. The cost of power in
this 100-horsepower plant, Mr. Grine
states, is 0.76 cent per brake horse-
power-hour, figuring fuel, labor, lubricat-
ing oil, waste, maintenance, deprecia-
tion, taxes and 7 per cent, interest on the
investment.

Properties of Heavy Oils

Letters are frequently received by
Power asking for the composition, heat
value, etc., of crude and other heavy oils
used as fuel in oil engines. The prop-
erties of such oils vary over a consider-
able range, even for oils taken from the
same field at different times, but the ac-
companying table gives what may be con-
sidered representative figures for the
composition, weights and heat values of
American oils.

PROPERTIE

■; OF cnroE 0

II,.S

CoMPOsmox BY Weic.ut

r^pecific
CJravity

Pounds

per
Gallon

B.T.r. PKR PorND

Kind of Oil

Carbon

Hydro-
gen

plmr

Oxygen

By Test

Com-
puted

Ohio

Pennsylvania, lislit ...
Penn.sylvania. li('av.\- .
West \'irKinia, light . .
^Ye.'^t Virginia, heav\'.

Texas . . .'

California

0.S.S4

0 . SL'O

0 si;;

n;,sio
0 . S52

0.147

n.iis

0.1.37
0.141
0.13:!
0.132
0.124

0,006
0.010

6 '.6(13
o.nos
0.010

O.OOo

0.(113
0 . 022
0.014
0.013
0.024
O.OIS
0.019

0..S00
0.S16
0.S.S6
0.S41
0.S73
0.92.^
0.9,59

6.6S
6. SO
7.40
7.02
T.2S
7.71
8.00

19,oS0
19,930
19,210
18,400
18,324
19,100
18,500

19,718
19,,")19
19.38.1
1S..S27
18,860
18,928
18,6,56

November 14. 1911

POWER

Wire in Compressor Piston

One of the most peculiar compressor
breakdowns with which I have come in
contact happened recently in the plant
in which I am operating.

The plant consists of one two-stage
compressor, the cylinders being set on
each side of a central belt wheel and
the cranks set at right angles to each
other. The power is furnished by a
single-cylinder 90-horsepower gasolene
engine.

One evening a severe knocking was
noticed in the low-pressure cylinder on
the crank end and the engineer in charge
immediately shut down.

The following morning I took off the
cylinder head, and upon removing the
piston found a collection of what looked
like headless ten-penny nails and a few
small pieces of cast iron.

Upon replacing the piston and tighten-
ing the nuts which held it on the rod, the
rod broke, showing it to be badly crystal-
lized. It also cracked, due probably to
the shock it had received the previous
day.

A new rod was made and put in, but,
before starting up, the intake piping was
gone over so as to prevent any further
scrap iron getting into the cylinder, al-
though this was unnecessary as the in-
take was adequately protected by screens.
Suspecting foul play, I left the intake
open above the compressor in order to
prevent anything being introduced from
outside the building.

I then started up, but in about an hour
I was forced to shut down as the low-
pressure piston was knocking again on
the crank end.

Imagine my surprise when, upon re-
moving the cylinder head, I discovered
another collection of scrap iron similar
to the first. This was a puzzle and I
lay off a day to thing it over.

While thinking over what I was up
ugainsf, and wondering if the machine
had turned into a scrap-iron factory, I
noticed a small sand hole in the face of
the piston. I poked into it and found
that if went clear through into the core.

This explained the mystery; some of
the wire used in reinforcing and support-
ing the core had not been removed, and
as soon as the sand hole was large
"enough (about 'i inch I some of the
pieces of wire had worked through into
the cylinder.

As the piston walls were too thin to
give a full thread I was forced to drill a

against the end of the car nozzle D. The
gasket between the collar C and the
nozzle is rather thick to allow for poor
alinenient. This device does away with
all pipe fitting, and the only tool needed
is a small wrench to tighten the set-
screws.

The coupling is first screwed on by
hand and the gasket is then compressed
by means of the setscrews. It is es-

, , , , , , pecially useful on cars in which the out-

hole through both faces of the piston

and put in a staybolt, riveting both ends

and finishing down flush with the piston

face.

The small hole in the piston also low-
ered the volumetric efficiency of the com-
pressor as it increased the clearance
volume on that end an amount equal to
the contents of the hollow piston.

The machine is again running properly.
If any engineer has run up against this
difficulty before, he has my profound
sympathy, only I wish he had told Power
about it so that I would have been "next."
Samuel S. Murdock.

Bannock. Mont.

SiiKstitiite Trap Bucket

I came to my present position about
two months ago and found one of the
bucket steam traps on the high-pressure
line leaking. I took it apart and dis-
covered that the bucket, which was 4
inches deep and 6 inches in diameter,
was badly corroded. I took a can 8
inches deep and 6 inches in diameter
and cut it down to the same hight as the
old bucket and then drilled a hole in the
center of the bottom and put it in the
trap. It worked satisfactorily until a
new bucket was obtained.

P. j. McEnaney.

Menard. III.

I'liion for Tank Cars

The accompanying sectional illustration
shows a union for connecting to the out-
let nozzle of tank cars. It is attached to
a long swinging length of pipe with a
swing joint midway of its length, so that
the cars do not have to be exactly placed
before connecting to them.

The union consists of a 4-inch cap A,
which is threaded loosely, so that it may

he easily screwed on by hand. It has I got a piece of a leather belt large
a hole drilled in it large enough so that enough to cover the heads and, fitting
the 2-inch nipple li may slide through this to the stud bolls, put the head back

Details of Union

let nozzle is up between the car timbers
or when the air-brake cylinder and truss
rods are in the way, making it almost
impossible to use a pipe wrench to tighten
up the fittings to prevent leakage. The
2-inch pipe runs to the suction of a
duplex pump, which discharges into the
storage tank.

S. M. Dunn.
Los Angeles, Cal.

Temporary Pump Repair

Once upon taking a job I found that the
feed pump had been left full of water
which had frozen in the water end and
had cracked the cylinder head as shown
in the sketch.

CRACKEn Cylinder Hfah

if. There arc also three holes tapped
for Vs-inch setscrews, which bear against
the thin collar C, which is screwed on the
end of the nipple li. and force it up

in place and ran the pump against 70
pounds pressure for 3(3 hours.

A. Blom.
Chicago, III.

POWER

November 14, 191 1

Handle for Furnace Door

Handles that have given satisfaction
for the past seven months on the fire
doors of a 300-horsepower water-tube
boiler were made by inserting a piece of
'/J -inch iron pipe in the holes intended
for the original wooden handle, as shown
at A. A second pin B, 8 inches long, was
connected to the first and a third piece C
was connected as shown. This extension

-:;:.'i

::.a

r-^n

f'-P

1

ik

Handle on Furnace Door

keeps the handle cool and saves several
steps when about to renew the fires.

M. C. Cook.
McCook, Neb.

Unequal Port Openintj

I have a slide-valve, cross-compound
engine of the traction-engine type. This
engine has a valve gear as illustrated
herewith, and owing to an accident it
became necessary to reset the valves.

I found that the eccentric was keyed to
the shaft, directly in line with the crank.
.After adjusting an equal amount of lead
on each end, which in this case was "_■
inch, by turning the engine over I had
about Is inch more port opening on the
crank end than on the head end, al-
though the point of cutoff was equal on
each end.

Can any reader of Power tell me how
to adjust such a valve gear so as to
get an equal amount of port opening on

Valve Gear

each end of the cylinder, and at the same
time have an equal amount of lead,
without rebuilding the valve gear?

When taking this matter up with the
dealer who sold this particular engine he
claimed that this was an excellent feature

in valve gears, but he was unable to
explain to my satisfaction the advantage
of this feature.

What is the efficiency of such a valve
gear? Would this be considered a prac-
tical engine?

Referring to the sketch, A is the en-
gine shaft, B the eccentric and C the
crank. The valve rod D gets its motion
by the combination of the sliding block
E, in the link F, and the action of the
eccentric, as it is connected to the ec-
centric arm G, between the eccentric and
the sliding block E. The reverse is af- '
fected by simply slanting the link F in
the opposite direction.

W. A. Mueller.

Bath, S. D.

Purchasing Hair Felt

Persons having to do with the pur-
chase of supplies may frequently find
it to their advantage to use the graphical

Showing Price of Hair Felt at Dif-
ferent Thicknesses

method to show the variation in price of
different sizes, weights or qualities, as
an aid in making an intelligent, econo-
nomrcal selection.

To illustrate the idea, I have plotted
the quotations received some time ago in
reply to an inquiry about hair felt. In
my case, it did not matter materially
what thickness was purchased, as it was
to be used for miscellaneous purposes.
If too thick, a layer can be readily di-
vided to any thickness desired. The
prices were as follows:

A glance at the plot which represents
this quotation shows a remarkable dif-
ference between thicknesses above and
below 1 inch. The heavy lines, repre-
senting the figures as quoted, cross on
the 1-inch thickness, and it is obvious
that one will get more of the material
for »he money by selecting 1 inch or
thicker. The price for thicknesses less
than 1 inch is expressed by the
equation,

P = 3'< + 314 /
and for thicknesses over 1 inch,
P = 7.3 (/ — 0.12)

where p equals cents per square foot,
and t equals thickness, inches.

K. L. Westcott.
Columbia, Mo.

Truing Up Rubber Pump
^'alvcs

I have a successful scheme for truing
up rubber pump valves. Glue a piece
of No. 2 emery cloth onto a steel disK
that is mounted on a short shaft and is
driven from any line shaft.

The valve is placed on the iron block,
with the stud in the center. The guides
are set square with the revolving disk.

Valve ^

I /:

©

-r^ 1

Rig for Truing Rubber Pu.mp Valves

When the valve is pressed against the
disk it is then ground true.

I have charge of four 40,000,000-gal-
lon pumps and grind over 1000 valves a
month in this way. It takes a man two
days to grind them.

A fair job can be done by securing the
disk to the end of any shaft and holding
the valve with the hand , it being mounted
on a wooden block similar to the iron
block.

This rig can usually be hooked onto
an emery wheel by putting it between
the safety collar and the nut and making
a guide as shown, bolting it to the stand
which carries the journals.

S. H. Farnsworth.

Chicasio. 111.

Repaired Economizer Mani-
fold

A manifold of a fuel economizer
cracked just around the fillet to the
flange.

The manifold was removed and fas-
tened in a lathe and the inside smoothed

Repaired Manifold

up as far as the branch. It was then
threaded, and a nipple screwed in place.
The nipple can be painted with either
red lead or smooth-on.

H. R. Blessing.
Philadelphia, Penn.

No%'ember 14, 1911

POWER

Two Designs of Oil Burning
Furnace

I am using oil and am getting good
results. I bum from 36 to 39 gallons of
oil per hour and develop from 155 to 175
horsepower.

The furnaces are also fitted for burn-
ing coal except that the grates are
covered with asbestos mill board to with-
in 18 inches of the back end. Bricks
are placed end to end from the bridge-
wall to the front, in rows about 3 inches

Effect of Temperature Change
on the Gravity of Crude Oil

The accompanying diagram shows the
results of a test for variations in gravity
of California crude oil by changing the
temperature, heating the oil from 40 de-
grees to 140 degrees Fahrenheit and al-
lowing it to cool; the readings were taken
at the points designated during the pro-
cess of both operations.

The curve drawn indicates the average
relation existing between degrees Baume,
gravity hydrometer and degrees Fahren-
heit and is applicable for conversion use;

Oil Extractor

The accompanying illustration shows
an oil extractor which I have perfected.
I; can be made out of any kind of tank.
I have a sump under my engine which
catches all of the drain water. This
water is then pumped into the tank by
a small pump.

I use ' J gallon of oil daily and reclaim
one-half of it. I think this is very good.
The sketch is self-explanatory. The brass

Design of Oil-bi;kning Furnace

apart, and are then covered from back
to front with bricks closely packed and
covered with clay and sand. This forces
the air from the back end of the grates
through the 18-inch opening and causes
it to travel between the asbestos covering
and the heated trick and clay above be-
fore reaching the fire. I have no bridge-
wall and find this to be the best furnace
I have tried.

Thinking to get better results, but fail-
ing utterly. I dropped the back end of
the grates, covered them as before, and
built a bridgewall to within 16 inches
from the boiler so as to force the pro-
ducts of combustion up toward the front
of the boiler. I also allowed some air
to come in at the bridgewall end of the
grates through a I -Inch opening. The
oil burner was turned downward so that
the flame was about 5 inches from the
bottom cf the furnace.

This produced so hot a Are that
the brickwork was melted and the
heat was fierce at the furnace front.
It took nearly twice the fuel to
get the same work done as was obtained
with the original furnace. The accom-
panying illustration shows how the fur-
nace was arranged.

Can anyone tell me why the second
furnace did not give satisfactory results?
P. H. Wavne.

Newton, Kan.

its plotting is based upon a mean center
of gravity of the points located.

The oil selected for the test contained

Oil Extractor

C

y1

y"

^

•

1.'^

^

y"

^

y

/

•

Readin

Simila

Heatir
Coolirii

?

V

y

^ ^

50 60

) 80 30 100
Degrees, Fohnerihci+

MO 120 130 I'lC

Diagram Showing Effect of Tfmperatiire Chances on the Gravity
OF Criidc Oil

close to 4/10 per cent, of moisture and Is sliding drain pipe is of the same length
regularly used in California for fuel on both sides of the U-bcnd. but the out-
purposes, let end is closed.

A. W. Lyons. W. I. Crawford.

Oakland. Cal. St. Louis, Mo.

748

POWER

November 14. 1911

Furnace Ard^es

On page 441 of the September 19 is-
sue, H. B. Jahnke writes of trouble with
furnace-door linings.

In the case of the ordinary size fur-
naces, say up to 6 or 7 feet wide, he can
have a firebrick arch built, with a rise
of 5 or 6 inches in the center, and sup-
ported entirely on the side walls. Piers
can then be built between the firedoors
and between the firedoors and side walls,
which have no supporting effect on the

Design of Furnace Arch

arch; these are easily and cheaply re-
newed when worn out. The illustration
shows the idea.

I have such an arch under one of
the boilers in the plant where I am em-
ployed which has worn out one entire
furnace lining, and is well along with the
second one.

A. G. Knight.

Omaha, Neb.

In reply to H. B. Jahnke's letter in
the September 19 issue regarding fire-
brick arch, I would say I have used the
dutch-oven type of firebox shaped like
a big arch and 6 feet square. Refuse,
such as sawdust and planer shavings,
fed through the top of the firebox by
conveyers, are burned mostly and very
good results are obtained. The arch will
stay up when well made until the bricks
melr away to almost nothing. I use the
best firebrick I can get and pay freight
for transporting it nearly 1500 miles.

I have a form made in the shape the
arch is to be, say two bricks lengthwise
and as near a half circle as practicable.
Ordinary arch brick is used with edges,
say, 2x2K> inches, and I build on over
the form with very thin fireclay as a
binder and use it sparingly; in fact, I
just dip the bricks and avoid working in
small pieces.

\Vooden blocks or bricks are employed
for supports under the form, and if the
bricks do not come tight over the form,
I lower the form enough to make them

tight without using split bricks. A second
arch is built over the first' in the usual
way. This holds the whole structure
together and should the first or main
arch get damaged from any cause. I can
continue to run until there is time to re-
pair it.

An arch like this made out of good
firebrick does not bend and warp like
iron lining, and will last a long time.

B. Zanadke.

Libbv, Mont.

Questions for Discussion

In reply to the questions asked by
H. R. Rockwell in the September 12 is-
sue, I wish to say that I do not believe a
single empty red-hot boiler will explode.

If a red-hot boiler were connected to a
battery under pressure, I believe that it-
would, if not protected by an automatic
stop valve, undoubtedly explode, because
when the water strikes the boiler shell
the seams would rupture, thereby releas-
'ing the steam pressure. The pressure in
the other boilers would be converted into
steam faster than it could escape, there-
by causing an explosion.

Cutting two or more boilers together
at unequal pressures will not cause an
explosion, provided care is taken in open-
ing the valve. If the difference in pres-
sure is great, say 50 pounds in one and
150 in another, a strain is put upon the
boiler shell containing the least pressure,
owing, to the steam space being heated
more rapidly than the part below the
water" line. I do not call this really dan-
gerous, but it is undoubtedly bad prac-
tice.

If one boiler in a batter^' explodes it
is liable to cause all to explode, unless
they are provided with automatic valves.
The reason is given in the first answer.

A condensing engine suddenly relieved
of its load win not increase in speed
when the throttle is closed, but will
run for some time if a vacuum is main-
tained. The vacuum will gradually drop,

as when steam ceases to enter the con-
denser it cannot maintain its usual vac-
uum.

C. E. Aldrich.
Patterson. Cal.

Sand in Bearings

Some engineers advocate using Sapolio
for cooling a hot box. It works very well
sometimes, especially if the parts do
not fit properly or" there is lack of aline-
ment, but I would not think of using
ii on a good machine as it will badly
score the pin and brasses.

What took my breath, was the editorial
favoring putting sand in a bearing. I
may be behind the times, but it makes
me uneasy to see sand anywhere near
the engine and I always feel like kick-
ing a man when I see him set his oil can
down on the floor or where it might pick
up grit.

J. O. Benefiel.

Anderson. Ind-

Pow er Plant Betterment

I was very much interested in reading
the article written by Mr. Bailey in the
September 5 issue under the above head-
ing, as well as others under the same
heading.

I agree with Mr. Bailey when he says
that very few of the engineers in plants
of 250 horsepower or under have indi-
cators. I have seen several plants where
the engineer did not know what an in-
dicator was, and many places where the
engine had never been tapped for an in-
dicator. One plant has been run for 40
years. I have heard some old engineers
say that they did not need an indicator
to set a valve for they could set it just
as well, or better, without it. I also
know of an engineer who can neither
read nor write. The people who employ
such men deser\'e to pay well for their
power.

In some of these poorly operated plants
an expert cannot better the conditions be-
cause the management will not listen to
bim. It seems to think it is cheaper to
run with a high operating cost than to
spend a little money for repairs or for a
new machine in order to lower them.
Usually they have no way of knowing
which would be the cheaper and they
just use their own judgment. In such a
place there is no chance for betterment.
E. V. Chap.man.

Decatur, 111.

November 14, 1911

POWER

Corrosion of Hot Water
Heater

In the October 3 issue of Power, page
524, is an inquiry from Asa P. Hyde, of
Binghamton, N. Y., who is having con-
siderable trouble with corrosion with a
hot-water heater.

Mr. Hyde says that the water in the
heater which is causing the trouble comes
from the city supply. We would also
judge from Mr. Hyde's letter that at no
time does the water come in contact with
steam or oil, but is heated entirely by
means of the brass coil to which he re-
fers.

We have on hand an analysis of water
from Binghamton, N. Y., marked "River
Water," which is given herewith:

ANALYSIS OK lUVEU WATEU

Incrusting Nonincrusting

Solids Pi-rCt. Solids PerCt.
Cjicium carbonate 2 :(."> .Sodium sulphate, none
Calcium sulphate . 0 2(1 Sodium chloride 0 40
CaVcium chloride. . none Sodium carbon-
Calcium nitrate. . none ate none

Magneoiura car- .Sodium nitrate. . none

bonale none

Magnesium sul- Total 0.40

phate 1 02

Magnesium chlor- Volatile

ide 0 14 Tree carbon di-

Iron and alum- oxide 0 29

mum sulphates, none Half-bound car-
Iron and alumina. 0 06 bon dioxide. . 1.03

Silica 0 20 Hydrogen sul-

Siispended matter 0 70 phide none

Total 4 67 Total 1.32

Hardness 3.50

Pounds in 1000 Alkalinity

gallons 0 . 67 .\cidity none

Free sulphuric

acid none

In this connection we call attention
to the presence of magnesium chloride
and to the fact that this river water is
fairly soft water, although the magnesium
sulphate in it would probably give rise
to scale.

The difficulty Mr. Hyde speaks of
would lead one to believe that the trouble
is due entirely to corrosion. This, if
caused by a water of the nature previous-
ly described, would undoubtedly be due
either to the presence of free carbon
dioxide in the water in sufficient amounts
to cause corrosion or to the presence of
magnesium chloride, which is accepted
by all chemists as being one of the most
objectionable salts which could be pres-
ent in a water used for such purposes
as Mr. Hyde describes.

It Is a very objectionable mineral when
present in boiler waters, being very cor-
rosive and quickly pitting and grooving
boilers.

Mr. Hyde's description of the effect
of corrosive water on cast iron, and also
the fact that he is troubled by red, rusty
water, which is hard to clear, is positive
evidence of direct corrosion. The fact
that other people in the town, plumbers,
etc., are having trouble with water fronts
and range boilers would go to confirm the
opinion that it could be attributed to a
corrosive water, and the best possible
way for him to arrive at some method of
stopping it would be to have an actual

sample of the water analyzed and a
recommendation made based on the ex-
act analysis as to what chemicals should
be used to counteract the effect of any
corrosive substances present.

The fact that the water in the same
locality has corrosive salts present would
certainly confirm the above opinion. It
is a problem which has been met and
taken care of many times.

The Kennicott Company,
By F. S. Du.nham.

Chicago Heights, III.

As to the article on corrosion of hot-
water heater, by Asa P. Hyde, in the
October 3 issue, I believe his trouble is
due to the water he is using. His boiler
compound or his fear of electrolytic ac-
tion occurring need not bother him, but
he should look after the water.

Chemically laden water will have dis-
astrous effects on iron, tending to set up
a corrosive action which, in a very short
time, makes it necessary to renew
parts.

The ingredients in the water which
tend to be so destructive when coming
into the heater and are deposited on the
metal are such that renewal of the cor-
roded parts is finally necessary.

I recommend that Mr. Hyde have the
water carefully analyzed and then put
in the new parts made up of a metal
which will withstand this action; of
course, this new metal must be such that
no possible electrolytic action can set up.
The combination of metals will always
tend to set up an action which is, and
has often times proved, to be as destruc-
tive as any kind of local conditions.
Nathan Owitz.

New York City.

Asa P. Hyde, on page 524 of the
October 3 issue, asks regarding the cor-
rosion of hot-water heaters.

I have had more or less difficulty along
the same line, not only with heaters, but
with boilers. In some cases the water
was so full of free carbonic-acid gas
that trouble was experienced in keeping
things tight; in others, the character of
the water was such that the scale pro-
duced acted on both the boiler shell and
the tubes.

The solution Is to properly purify the
wafer. In some Isolated cases too pure
water has brought about the same re-
sults. The remedy is obvious: add some
alkali to make the water slightly impure.
It is advisable in some instances to fre-
quently change the water In the boilers
so as to prevent the possibility of its
becoming absolutely a distilled water,
which might happen In a closed healing
system.

Hknry D. Jackson.

Boston, Mass.

Adjusting the Mercur}'
Column

In the issue of October 3, Luke J. B.
Marier describes how he put a screw
adjustment under the cup of his mercury
vacuum gage to keep the level of the
mercury in the cup constantly even with
the bottom of the scale. He may have
been perfectly right in doing this, but I
v.ould advise anybody desiring to fol-
low his example to first measure the
scale and see if it really is a scale of
inches or if each pound pressure on the
gage measures 2.04 inches on the scale.
If not, then the maker of the gage has
probably made an allowance for the level
of the mercury in the cup going down
as that in the tube goes up.

If, as in Mr. Marier's case, the level
of the mercury in the cup falls 1 inch
while that in the tube goes up 27 inches,
thus indicating a 28-inch vacuum, and if
the maker has made the proper allow-
ance, each inch of vacuum on the gage
will be found to measure Sj of an inch.
In this case it is not only unnecessary,
but wrong, to change the level of the
mercury in the cup, and the only adjust-
ment needed is to see that the mercury
in the tube goes to "0" when the vacuum
or the pressure is zero.

A. E. Mueller.

Mavville, Wis.

I was interested in Mr. Marier's ac-
count, in the October 3 issue, page 526,
of his experience with mercury columns,
as it reminded me of two points that
often escape the notice of the practical
engineer. One is the adjustment of the
scale as noted in his article, to give the
true hight of the mercury column; the
other, a point that may have as great
significance, is the presence of water
on top of the mercury.

Where the gage is connected direct
to the condenser, with no intervening
trap, water often collects in the tube.
Many an engineer does not realize that
this may introduce a serious error.
Thirteen and a half inches of water is
equal to an Inch of mercury in the pres-
sure it exerts, so the pressure of this
much water will cause the reading on
the mercury column to be an inch low.

Of course this error may be corrected
by a calculation, but the most satisfac-
tory way is to keep the water out of the
mercury column. This may be done by
putting a trap in the line leading from
the condenser to the gage. A trap may
be bought or it may be made.

The accompanying illustration shows
the design of a trap which can be made
easily by a pipe fitter. Take a piece of
2'''>-inch pipe about 12 inches long and
drill and tap it near the ends for a
pctcock and two '<-lnch nipples. The
nipples should he as short as possible,
and should have elbows with short nip-

750

POWER

November 14, 191 1

pies screwed on so that the two nipples
point at each other. Cut a piece of
glass tubing to the proper length and
fasten it to the nipples with short pieces
of rubber tubing, which should be wired
securely to prevent leakage. This ar-
rangement makes a simple water glass.
Screw a cap with a petcock in the
middle to the lower end of the 2'/.-inch
pipe, and another cap with two pieces of
J4-inch pipe screwed into it, one pro-
jecting downward about 4 inches. To
the upper end, connect the projecting
pipe to a valve in the line from the con-
To Gage -.

Trap for Mercury Column

denser, and run the other to the mercury
column.

When water collects in the pipe from
the condenser and fills the trap so that
it shows on the water glass, the valve
in the condenser line may be closed
and the two petcocks opened, allowing
the water to run out. This operation
takes only a few minutes and insures
a dry mercury column.

If no water shows on the mercury
gage, have all connections tisht. so that
there is no leakage of air. and have the
scale measure from the surface of the
mercury in the well. One may then be
sure that the gage will give a correct
reading.

J. F. iVlowAT.

Joliet. 111.

Taper Piston Fit

In the October 17 number, page 596,
F. W. Brady describes a method of put-
ting the piston on the rod with a straight
"easy-sliding fit — just tight enough not
to wabble." I would consider such a
job unsafe in an engine of large size.

Mr. Brady especially objects to the
practice in marine work where the pis-
ton is forced on tight and the rod end is
sometimes riveted over. A marine en-
gine must, above everything else, be de-
pendable. It is sometimes put to very
severe service, such as being reversed
and going full speed astern as soon as
possible after stopping.

When running • in a heavy sea the
wheel is often partly out of the water
and the engine races violently.

The stopping of an engine, even for a
few minutes in heavy weather, may cause
the loss of the vessel and her crew. I
think that the builders of these engines
are justified in putting the pistons on as
though the job was to stay finished for-
ever.

James H. Ca.mpbell.

Bloomington, 11!.

Engine Runs v\ ith Steam
Valves Closed

Referring to O. Lantz's letter in the
issue of September 5. the cause of his
engine running with the admission valves
closed is probably leaking steam valves
and tight exhaust valves. The steam
which leaks into the cylinder in front of
the piston escapes through the open ex-
haust valve, while that behind the piston
is prevented from escaping by the closed
exhaust valve on that side.

Newly fitted Corliss valves are not al-
ways tight; in fact, I believe, as usually
fitted, they are more likely to leak than
not.

I make it a practice to take these
valves out frequently and if they are not
wearing to suit me I drawflle the high
places, especially the head or part that
extends beyond the ports. This has a
tendency to cause the high parts to wear
faster and bring the low parts into con-
tact with the seat.

It has always seemed to me that there
was a tendency for the solid ends of the
valves to wear less than the part cover-
ing the front, owing to the greater surface
which the solid parts have.

With a double-eccentric engine in
which the steam valves are set with little
or no lap, when the steam wristplate is
unlatched and the exhaust wristplate
is latched, live steam might pass into
both ends of the cylinder and cause
the engine to run as previously de-
scribed.

J. O. Benefiel.

Anderson. Ind.

Engine Knocks

In the October 3 issue, page 524, W. A.
Mills requests information as to a knock
in the low-pressure cylinder of his en-
gine.

If he will remove the low-pressure
cylinder head and try the nut on the
piston rod, with a large wrench, he will
no doubt find it loose. A loose piston
will make a knock hard to locate, though
it is often attributed to a loose crank
pin.

After tightening the piston-rod nut. it
is well to mark the nut and rod so that
future movement can be detected. If the
nut is found tight, then examine the
crank and crosshead brasses to see if
they are cracked; at the same time see
if the crank pin is loose; an inspection
should also be made of the crosshead
pin.

The pins may have become smaller
through wear and they should be cali-
pered to see if they are true. If badly
worn it may be necessary to plane off
more clearance where the brasses come
together, so that the brasses can be
keyed to the right place.

Too much compression will also cause
a bump in the cylinders and should be
remedied by an adjust.Tient of the valve
rods. Indicator diagrams should be
taken to see if the trouble lies in this
direction.

The clearance space in both cylinders
should be looked after to see if the piston
touches the heads at the end of the
stroke.

A. Rauch.

Swissvale. Penn.

Flywheel E.xplosion at \\ est
Berlin

In the October 3 issue, G. H. McKel-
way takes exception to certain statements
in my letter concerning the flywheel
wreck at West Berlin, and practically
accuses me of carelessness in letting a
circuit-breaker get into such condition
that it would not open.

I want to ask Mr. McKelway if he had
worked day and night for three or four
months to get his plant into as good
condition as possible, would he sit up
until 1 a.m. to pull a circuit-breaker to
pieces when it had never before failed
to his knowledge?

After the flywheel explosion the plant
was closed down for a week and elec-
trical energy was supplied by another
company having its terminus in the same
town within a few feet of the tracks sup-
plied by my plant. These lines carried
625 volts while my station carried but
575 at peak. When I started up I had
not been informed of this; therefore I
cut in with 575 volts as usual at 9
o'clock Sunday morning. At 9:30 our
cars on both lines got to the end of their

November 14, 191 !■

■p O \V E R

751

respective lines. I was standing near
to the throttle watching to see how things
were going, and the night engineer, who
was about half way between the throttle
and the switchboard, was also watching
for whatever might develop.

The instant the car carried by my
plant reached the end of the line, as
shown by the ammeter, the generator
shot fire and the engine began to speed
up. The night engineer jumped for the
circuit-breaker and I closed the throttle.
This incident led me to think of my ex-
planation of the explosion of the other
unit. Thirty seconds had not elapsed
froin the time that load went off and the
engine started to speed up before it was
making double its normal speed (which
was 88 revolutions per minute), and I
will take my oath that the steam valves
did not open for two minutes after the
throttle was closed, the circuit-breaker
opened and the main switches pulled.

I got started up again after notifying
the superintendent of motive power of
my trouble and was informed that it
would be necessary to carry higher volt-
age. Twice that afternoon 1 saw the load
go to a point where the circuit-breaker
ought to have opened. I had never seen
it fail before so I reset the trip for 100
amperes less but did not get enough
load to open it the rest of my run.

I notified the night engineer when he
came on at 6 o'clock and told him to
watch it, which he did. The next day it
rained and the air cooled down about
■10 degrees. The first thing I had to do
after getting into the station was to put
that breaker back into place, and I had
to,,^jt it back several times that day and
the next, and have not known it to stick
since.

Now I would ask Mr. McKelway if
there was carelessness or neglect, and
what he would have done had he been in
my place?

W. E. Chandler.

Northbridgc. Mass.

Centrifii<jal Puinp Capacity
and Speed

T. W. Holloway, in his article "Cen-
trifugal Pump Capacity and Speed," in
Pott'EK for October 3, page S08, states
that theoretically the rim velocity of the
pump runner should be equal to the
velocity that a body would have after
having fallen through a distance equal
to the total head pumped against. This
statement is not borne out by a mathe-
matical analysis as will be shown.

A pump foinner forces water against
a head by virtue of the centrifugal force
it imparts to the water passing through
it. Now the centrifugal force acting on
unit weights at unit radius and at a
velocity V is

9

In the case under consideration F is pro-
portional to and equal to the head h.

Therefore,

;, = ';:

The head pumped against or hight of fall
in terms of j; and l" is

- !/

Now it is evident that h in the first
equation is of twice the value of h in the
second equation, since V and g have the
same respective values in each case; in
other words, a perfect centrifugal pump
will raise the water to a hight twice
that due to the velocity of the circumfer-
ence of the runner. As an example, sup-
pose the rim speed of the runner to be
46.8 feet per second; a weight would
fall freely through 34 feet to acquire
this velocity and the total lift of this
perfect pump would be 68 feet.

Mr. Holloway's equation

! ■ = 480 1 h
where V is velocity in feet per minute,
is very close to the equation used in
designing ordinary centrifugal pumps,
includes quite an efficiency factor and
therefore is some distance from the theo-
retical point.

N. C. Hurst.
.^spinwall. Penn.

Knjiineens' Waj^es

In the editorial published in the
October 10 issue under the above title,
there is much that is good. It is true
that engineers are working for laborers'
wages; in fact, for much less, if the
weekly wages are reckoned by the num-
ber of hours put in on the job.

In Massachusetts there is some pro-
tection, as the license law prevents un-
scrupulous employers from hiring ineffi-
cient help, who in reality are only "stop-
pers and starters."

The editorial speaks of the charges
of graft hurled at the engineer, and ex-
presses the belief that not more than 5
per cent, would accept graft. I believe
that 5 per cent, is high and that the
majority of engineers do suffer by the
acts of the few.

This charge of graft does not apply
to the engineer alone, but will he found
in any profession where the party is al-
lowed to purchase supplies. If there is
one thing more than another which tnakes
engineers angry, it is to have an ad-
vertiser continually harping on the sub-
ject of "graft." Surely the crusade of
"graft" must have reached all the "graft-
ers" by this time, and if the number is
less than S per cent., there ought to be
enough business among the other 9,S per
cent, of honest engineers to appeal to
them for their custom. This is not an
appeal from the "grafters," but a pro-
test from the others. The advertisements

of Power are read by managers and
superintendents as well as by the engi-
neer, and it is giving them the impres-
sion that they can hardly trust any en-
gineer in their employ.

It looks to me more like coercion than
anything else. That if an engineer is
not buying certain kinds of supplies he
is a grafter, because none of the other
supply houses are not crying down graft.
I, for one, do not care to see this kind
of advertising, and am sure that it makes
no appeal to the engineer, I hope this
letter will be published, for it is the
sentiment of not only myself but of
others who have discussed the matter
with me.

WiLLi.A.M J. Massey.

Cambridge, Mass.

Scrub Kngineens

Replying to the question asked by J.
\V. Dickson in his letter on page 525 of
the October 3 number, I would say that
a man is an engineer in Massachusetts
when he qualifies for his license at the
State house. When he gets that license
no night watchman or carpenter can
keep him out of a job by running it.

Such conditions as Mr. Dickson writes
of prevail in a number of places, but
not in any State which has an engineers'
license law.

The license has the effect of raising
the standard of the engineer and the ser-
vice and will protect a man who has
spent a lifetime at the business.

The only remedy for the conditions
which Mr. Dickson describes is a license
law.

WiLLiA.M F. O'Recan.

Brighton, Mass.

In.stallinir Oil Tanks

Referring to the many answers to my
inquiry regarding the unloading of fuel
oil, which was published in the August
1.^ number, I beg to advise that the
Standard Oil Company has informed me
that no pressure whatever will be allowed
on my tanks, therefore some other means
must be used. Who can suggest an ac-
ceptable method ?

W, W. Warner.

Kent. O.

Improved Stop \'alve

An excellent idea is shown in the valve
illustrated and described by Yaekichi
Sekiguchi on page ^2.^ of the October 3
issue, and is very similar to a valve got-
ten out several years ago by a well
known valve manufacturer whose valve
has merit beyond that mentioned by Mr.
Sckiguchi, inasmuch as it is a truly
"spring-seat" valve accompanied by all
the self-compensating features of such a
mechanism.

Franklin M. Patterson.

|.^r<;rv City. N. J.

752

POWER

November 14, 191 1

Flow of Air tlirou'^li iiii Orifice

Give formulas, for the flow of air,
through an orifice in a receiver, into the
atmosphere, under constant conditions of
pressure and temperature. Also, would
the coefficients of contraction used in
these formulas for various-shaped open-
infis apply equally as well to steam and
water?

C. E. S.

Numerous empirical formulas are to
be found for the flow of air through an
orifice; based largely upon the findings
of different investigators.

The theoretical flow of air through a
circular orifice, as given in "Kent," page
5S9, and considering the air to be at 60
degrees initial temperature, is

W

■ 0.000491

I r P-, v''--"^ /P-. x'-'i

where,

W — Pounds discharged per second;
flf — Diameter of orifice in inches;
Pi = Initial pressure, or that inside
the receiver, in pounds per
square foot;
?;:= External pressure in pounds
per square foot.
In practice this must be multiplied by a
coefficient of discharge which varies
slightly with the size of opening and the
head. However, for all practical pur-
poses this coefficient may be taken as
0.6.

The same coefficients for nozzles and
different-shaped openings would not be
used for air, steam and water.

Condensation in Bare Steam Pipe

How may the quantity of steam con-
densed in uncovered steam piping of vari-
ous sizes be calculated?

F. W. O.

Experiments by George M. Brill, re-
ported in the Proceedings of the Ameri-
can Society of JVlechanical Engineers,
volume XVI, page 827, showed a con-
densation of 0.846 pound of steam per
square foot of bare pipe per hour with a
pressure of from 109 to 117 pounds
gage and a temperature of the air of
from 58 to 81 degrees. This is 2.706
B.t.u. per square foot per hour per de-
cree of average difference of teinpera-
f've.

L'vperiments reported by H. G. Stott
in Pg -'ER, of December, 1902, give 2.708
B.t.u. tor the same quantity.

The quantity may be influenced con-

Questjons are^

not answered unless

accompanied by the^

name and address of the

inquirer. This page Is

for you when stuck-

use it

siderably by the flow of air over the
surface. If the conditions are such that
the heated air can get away readily, al-
lowing cooler air access to the pipe, the
condensation will be more rapid than if
the circulation is restricted.

The total heat in a pound of steam
at 165 pounds absolute (about 150
pounds gage) is 1195 B.t.u. Its tempera-
ture is 366 degrees. If the average tem-
perature of the room is 66 degrees, the
average difference will be 300 degrees.
Assuming that the transmission per de-
gree of difference will be 2.7 B.t.u. per
square foot per hour per degree differ-
ence of temperature, each square foot
of surface will radiate

2.7 •: 300 = 810 B.t.u.
per hour. The steam will be condensed
to water at 366 degrees, each pound of
which will contain 338 B.t.u. Each pound
of steam in condensing to such water
will give up

1195 — 338 = 857 B.t.u.
and each square foot of surface will
condense

810

-^-— = 0.94 pound

per hour.

The condensation for other pressures
and temperatures may be computed by
taking the corresponding values from the
steam tables.

Gas Engine Exhaust Heating

Water is injected into the exhaust pipe
of a gas engine to cool it and muffle the
sound. This water instantly flashes into
steam. Is there any practical way in
v.'hich this steam may be used for heating
purposes?

C. J. B.

It is not practicable to use steam made
in the exhaust pipe of a gas engine for
heating purposes on account of the cor-
rosion which will take place in the pip-
ing from the condensation of the gases.

The heat inay be utilized by passing
the gases through a heater similar to the
closed heaters used with steam engines.

Horsfpouer oj Belting ■
What horsepower will be transmitted
by a double leather belt 39 inches wide
running over a flywheel 16 feet in diam-
eter?

F. M. P.
For a double belt 45 square feet of

surface passing over a pulley in one
minute will transmit one horsepower.

The belt is 3.25 feet wide, and the
pulley is 50.26 feet in circumference.
Therefore, the belt will transmit

.1.25 X .so.2.5

: = 3.03 horsepower

for each revolution the pulley makes per
minute.

This is for a belt working under fair
conditions of tension and speed. By
excessive tension it may be made to do
a great deal more for a short time.

Collapsing Pressure of Cor-
rugated Flue

How is the collapsing pressure of a
corrugated furnace flue calculated?

B. W. E.
Multiply the square of the thickness

of the flue in thirty-seconds of an inch by
1200 and divide the product by the
greatest diameter in inches multiplied by
the square root of the length of the flue
in inches.

Shims ill Connecting Rod Ends

What are shims and for what purpose
are they used?

C. R. E.
Shims are thin strips, usually of metal,

used to fix or to limit the distance be-
tween parts of machines. In connecting
rods they are placed between the brasses
and the rod ends to preserve the correct
rod length and to aid in taking up the
wear of the brasses.

Efiective Pressure of a Scren.ii

How can I determine the force exerted
by a screw moved by a lever of a given
length and a known pressure at the end
of the lever?

G. P. P.
The effective pressure exerted by a

screw is modified to an unknown degree
by friction and is undeterminable by
calculation. In some cases the reduc-
tion due to friction has been estimated
at 75 per cent, of the power applied, and
in others at 50 per cent. It is a case
where the actual force exerted will have
to be estimated.

November 14, 1911

POWER

753

Issued Weekly liy tlie

Hill Publishing Company

JOHW A-HiLL, Pn?s. audTiva^. BOB'T McKKAS,Sec'j-.

505 Pearl Street, New York.

123 :?oatb Uichi^an Boolevanl, Chicago,

6 Bouverie Slreel, London, R C
Vawr d«n Linden 71— B«rUu, N. W. 1,

Coripspondence suitable for the col-
umns iif Power solicited and paid for.
Name and address of correspondents
must be given — not necessarily for pub-
lication.

.Subscriplion price S2 per year, in
advance, to any post ottice m the United
.States or tlio possessions of the United
.States and le.viro. S:i 10 Canada. So
to any other :v>reign t-oiintry.

Pay no iiioi'ey to solicitor.s or aEenIs
unless they can show letters of authoriza-
tion from this ofiice.

Subscribers in (!reat Britain, Europe
and the British Colonies in the Eastern
Hemisphere may send their sub.script ions
to the London Othce. Price 21 Shil-
lings.

Entered as second class matter. De-
cember 20, 1910. at the post oHice at
-New York, New York, under the Act
of Jiarch 3, 1S79.

Cable address. " Powpitb," \. Y.
Business Telegraph Code.

CIRCULATIOX .^T.iTBUEST
Of this itittfir 32.0iHt fo/n'cx an' jiriiitcil.
Xone sent fire rruularly, no returns from

neirs companiis, no hack nutnbers. Figures

arc lire. n>t clrculalimi.

Contents paub

An Office BniUllnir Central .station 720

Notes on Crude Oil Knel ToO

rioncer Power Plant of California 7:'.1

A Commercial Water I'ower I'roblem.... 7."2

Largest Corliss Engine on the Pacific

Coast 7:14

Novel Features of Mine Power S.vstcm... 7:i.'»

Kl.vwheel ETploston, EarininKton, Utah.. 7S7

Half a Billl.m Tons of Coiil 7ns

K^'windin;: a Direct Current Generator. . 7;!0

Failure n{ a (lenerator iMie to a Swiniring

Itpen Circuit 741

Flywheel Wreck nt llacerly Shoe Factory 742
Effprls of .'■iilphnr in Fuel Oil or Gag.. . 74:'.

The •;rine Cnule f»ll On.s Pro<Iucer 74:<

Properties of Heavy Oils 744

Pracllcnl I^-lters :

Wire In Cnmiiressor Plsdm . . . Sul»-
slilule TrH|i rsurk.'i. ., .Union for
Tank I'nr" T"'ni|Mirnrv Pump Ite-

pnlr. .. .Handle for Furnace Koor
.... Un.-.|un! I'..rt Openlns. . . . Pur-
■ ha-inir Il.Tlr Felt . . . . Tnilna I'p
Rnl.lK-r Pump V.nlvoN. . . . Nr-w Wav of
Parking :i Stunini; It.ix . . Itepiiired
Economizer Manifold .... ICfTect of
Temperntur*' *'hanire on the tlrnvltv
of Crude Oil . . .on Extractor. . .74.">-74T

niscusslnn l.el|,r» ■

Furnaii' Anlin. .... fjur-utlnns for
Ii|s,'u««lon. . Hand In Bearlnt'.x. . . .
I'nner Plnnl Tlotlermenl ... .Corro-
sion of llol Water Ilenler. . . . Ad-
Justlnc the Mercury Column . . .
TupT Piston Fit ...Rnelne Ituns
with Hienm Vnlves Closed . . , r'ntrtne

Knocks FIvwhnel Explosion nt

West Berlin . Cent rlfuen I Pump
Cnpnrlir nnd Speed Eni:lne<rs'
Waees .... ficruli Enelneers ... In-
•tnlllne oil Tanks. . . .lmprove«1 Stop
Vnlve 74«.7.'.l

MllorlBls 7.-.:»-7.'i4

rreeoollne Plant of the Snnfii Ffi R«ll-

The Panama Pacific Exposition The "Block" Central Station

A Tim-Iy n<-

.-.n

With the plans for the Panama Pacific
Exposition now well under way, it seems
opportune to call attention to the neces-
sity for having the engineering features
form a prominent part of the program.
This is especially fitting: first, because
the exposition is to commemorate the
building and completion of the Panama
canal, one of the greatest engineering
feats in history, and, second, because
through its application to engineering
it will be able to exert a potent and
lasting influence.

Going back to the records of the
Centennial Exposition at Philadelphia
in 1876, we find therein not only a large
amount of space devoted to the descrip-
tion of engineering apparatus, but also
the reports of very complete tests upon
much of the apparatus. For the purpose
of making these tests a board of promi-
nent engineers was appointed and the
importance of their work is evinced by
the fact that it is still the standard of
procedure, and the basis of the official
unit of boiler horsepower, which was
defined as equivalent to the evaporation
of thirty pounds of water into dry steam
at seventy pounds pressure from feed
water at one hundred degrees Fahren-
heit.

D'lring the intervening period between
1876 and the present, numerous exposi-
tions have been held, but, with the pos-
sible exceptions of the Chicago and the
St. Louis Expositions, they created only
a passing interest and left no permanent
effect. This was largely due to the fact
that they were little more than show
places in which the exhibitors advertised
their wares.

With the rapid development in prime
movers during the past few years and
the revision of certain engineering equiv-
alents as a result of more refined meth-
ods of scientific research, many of the
engineering standards are now in a
chaotic condition. Therefore, the lime is
ripe for some authoritative commission
to readjust these standards to meet the
needs of modern practice, A prominent
engineer. Charles C Moore, of San Fran-
cisco, has been chosen as president of
the Panama Pacific Exposition, and with
this start it is hoped that the work will
fulfil the expectations of the engineering
profession and make its influence in this
field lasting.

In many cities, especially on the
Pacific coast, there exist what for lack
of a better term may be called "block"
central stations. One such, located in
Los Angeles, is illustrated in this issue.
The "block" station may be described as
a station which serves anywhere from
two to a dozen or rr.ore buildings in its
immediate neighborhood as, for instance,
all of the buildings on a city block.

Such a station possesses possibilities
which the usual type of central station
does not. From the "block" station not
only electrical energy may be distributed
but steam for heating and other pur-
poses, water under pressure for elevator
work, and even vacuum-cleaning service
and brine for cooling purposes may also-
be supplied economically. The large
central station is unable to supply any-
thing but electricity to any of its cus-
tomers except those in its immediate
vicinity.

.4t the present time, in practically all
of the industries, every effort is made
to utilize the byproducts with profit. The
light, heat and power industry should
be no exception to the rule. The chief
byproduct in power generation is ex-
haust steam. In a great many localities
the most profitable use to which ex-
haust steam may be put is to pass it
through the heating coils. Hence, the
"block" station seems more logical than
the exceedingly large central station
which is the common type at present.

In the municipality of New York the
"block" station does not thrive. If an
individual, firm or corporation wishes to
lay conduits or pipes under the streets
of New York City for the purpose of
distributing for profit to outside parties
electricity, gas, steam or the like, a
franchise from the city must first be ob-
ti^ined, and a franchise is not always
easily obtainable. This may explain why
"block" stations are not numerous, but
it does not explain why Ihcy scarcely
exist at all. A franchise is not required
to pass conduits and pipes from one
building into those which stand along-
side nf it, and surely there must he many
groups of two or more adjoining build-
ings in the city which could be served
advantageously by a single plant con-
tained in one of them.

We all know that if the "block" sta-
tion were to become nuinerous, central-
station business would suffer. What this

754

POWER

November 14, 1911

fact has to do with the other fact, to wit,
that "block" stations are not numerous
in New Yorlt City, we do not know. We
only know the facts themselves. And
we also know that the city itself found
it most difficult in attemptinj; to make
one of its plants into a "block" station.
New York City's Hal! of Records con-
tains a well designed power plant of
such size as to be capable of lighting and
warming the City Hall and the city court
house which are less than one short
block away. Someone in the borough
president's office made the suggestion
that the Hall of Records' plant be made
to serve these buildings with heat and
light and thereby do away with central-
station service in them. The suggestion
being attractive, word was given to go
ahead.

In order to carry out the suggested
scheme it was necessary to extend steam
pipes and electric conduits under Cham-
bers street. It seems, however, that the
carrying out of this plan required the
sanction of another city department and
when the latter found out what was in
the wind, difficulties arose. We are in-
formed that practically no objection was
made to laying the steam pipes (which
was done) but the laying of electrical
conduits was successfully held up. As a
result the electrical load upon the Hall
of Records' plant is not great enough at
present to furnish exhaust steam for
all the buildings and consequently this
has to be supplemented with live steam.
.Another incident closely connected with
the foregoing relates to supplying light,
Iieat and power to the new municipal
building, located across the street from
the Hall of Records. Owing to the sub-
way passing through the basement of the
municipal building, little room is afforded
for a power plant. However, the plans
call for a heating plant in conjunction
vith central-station lighting and power
service. It is understood that, here again,
the suggestion was made to place some
additional units in the Hall of Records'
V'lant (for which there is adequate space)
and supply the new building from this
source. This would have made an ideal
arrangement, and we ask again. Why
was it not adopted?

Tile New York License Board

Whate\er may be the prevailing view
legarding the failure of the new charter
for New York City to pass the legislature
there can be only regret upon the part of
those who have to do with the examin-
ation and licensing of engineers that
the proposed change in that respect did
not materialize. At present this is a
function of the police department. Under
the provisions of the new charter the
licenses would have been issued by the
Commissioner of Licenses upon the
recommendation of a board composed of
one member suggested by the National
Association of Stationary Engineers, one

by the International Union of Steam En-
gineers and one other. It is certain that
a board constituted in this way would be
able to pass with the intelligent apprecia-
tion which comes of personal service in
the same line upon the capacity of candi-
dates, and that any attempt to grant li-
censes for any other cause than merit
or to withhold them for any other cause
than incapacity would meet with prompt
resentment by the qualifying associations.
It is to be hoped that the matter will
not be dropped, but that some way may
be found even yet to bring about this
desirable arrangement.

Feed Water Regulators

What is the use of a feed-water regu-
lator?

Ninety-nine men out of a hundred
would say: "To '.^eep the water level
constant."

Well, what is the use of keeping the
v.ater level constant? So long as the
water is not allowed to get so low as
to endanger the heating surfaces nor so
high as to be carried over with the
steam, what difference does it make if the
water level does vary an inch or two?

The answer is that a perfectly constant
water level is supposed to indicate that
the feed water is entering the boiler at
exactly the same rate with which the
steam is being drawn off. In other
v.-ords, that the rate of feeding is
graduated or variable. In average prac-
tice, however, an automatic feed-water
regulator is either wide open or tight
shut and there is no intermediate posi-
tion. It keeps the water level apparently
constant by varying the relative lengths
of the open and shut periods. It is just
this feature which might reasonably be
objected to on two distinct grounds: first,
the heating of the feed water, and, sec-
ond, the metering of the feed water.
Suppose a one-hundred-horsepower boiler
to have a water surface of ninety square
feet and to be evaporating at its rated
capacity of thirty thousand pounds per
hour. If the boiler-feeding capacity be
sixty thousand pounds per hour, it is
evident that the automatic regulator will
be open just half the time, and if the
regulator be adjusted to open and shut
with a variation of one-quarter inch in
the water level, the periods of feeding
and no-feeding will each be four minutes
long. Similarly, if the regulator permit
a water-level variation of one-half inch,
these two periods will each be lengthened
to eight minutes.

During the period of no-flow the water
in the feed-water heater will become
very hot, but during the period of flow
the water will not have time to take up
sufficient heat from the heater and will
enter the boiler at too low a tempera-
ture. The harmful effects of such varia-
tions in feed-water temperature are
noticeable both in the fuel consumption

and in the wear and tear of both boiler
and heater. The extent of injury gen-
erally increases with the temperature
range and also with the frequency of
temperature change.

There is at present a very pronounced
movement in favor of accurately measur-
ing the amount of feed water to boilers,
and this, of course means that the
metering devices must be capable of
handling very hot water. Numerous
satisfactory methods for measuring cold
v>ater have been upon the market for
many years, but the number of devices
that are permanently accurate with hot
water is quite limited and these give
the best results only when the rate of
flow is reasonably uniform. Constantly
recurring fluctuations in the rate of flow-
ranging from zero up to full capacity
are almost fatal to accurate hot-water
measurements.

Fortunately, however, there are at
least three different methods of reducing
the extent and frequency of fluctuations
resulting from an automatic regulator
jnd in most cases all three methods may
be used at the same time.

The first method consists in placing a
small bypass pipe containing a valve
around the regulator, thus allowing some
water to be fed during the period when
the regulator is closed. So long as this
bypass valve is not opened too wide for
the minimum rate of steaming there will
be no danger of flooding the boiler. In-
stead of the bypass pipe, a notch or hole
can be made through the valve disk or
seat of the regulator.

The second method consists in having
a throttling valve in the main feed pipe
either before or after the automatic regu-
lator. This valve can be throttled to
such an extent that the maximum flow
with the regulator open will be only
slightly in excess of the maximum rate
of steaming and consequently the dura-
tion "regulator-open" period will be in-
creased. This narrowing of the limits of
m.inimum and maximum velocities also
reduces the frequency of regulator action.
The third method consists in adjusting
the float of the automatic regulator so
as to make the device less sensitive, thus
permitting a somewhat greater variation
in the water level. This reduces the
frequency of regulator action.

These three suggestions may involve
an occasional sounding of the high- or
low-water alarm, but it will produce a
flow approximately proportionate to the
rate of steaming with the advantages al-
ready enumerated.

More or less successful efforts have
been made to produce an automatic regu-
lator that will permit a variable rate of
flow and to adjust this rate to approxi-
mate a rate of steaming. Such a device
might have to sacrifice slightly in the
maintenance of an exact water level,
but this in itself is not necessarily a de-
fect.

November 14. 1911

P O \V F. R

Precoolinj^ Plant of the Santa
Fe Railuav

R. W. Allison

Precoolinc

Precooling is a distinct departure in
refrigerating work. It is often erroneously
confused with tlie term cold storage,
but, while necessarily involving a central
refrigerating plant, it relates essentially
to transponation, inferring a "time-limit"
process. The problem of transporting
perishable products to a terminal market
many hundred miles distant without
losses has long seriously confronted the
railroads of the world, and vast sums
have been expended in experimental
work in an effort to discover an adequate
method for the adaption of mechanical
refrigeration to railway conditions.

The placing of such products in cold-
storage rooms to chill to the desired tem-
perature has proved unsatisfactory for
many reasons. This demands excessive
handling, the unloading and reloading of
trains and the necessary equipment re-
quired therefor; also there must be con-
sidered the great expense thus involved.
The time consumed in these labors, with
the addition of from 48 to 60 hours for
cooling treatment, as found under usual
conditions, places an almost indefinite
period of time upon shipments. Again,
the ultimate market becomes an issue,
the purchaser is left in doubt as to the
actual length of cold-storage treatment,
and the age of the product. The abuse
of cold storage in this instance, as in
many others, is evident; instead of being
used legitimately for preparing for ship-
ment, with reasonable time restriction, it
is utilized for holding the product for
ihe most valuable market.

Precooling accomplishes the desired
result in a much more efficient manner,
rendering an accordant temperature in
from four to five hours, without any
handling of the product. It is the im-
mediate reduction of the temperature
within the loaded refrigerator car itself,
under a scientific treatment of cold-air
circulation. Necessarily, this is attained
by the use of a refrigerating plant, sup-
plemented by a special balanced-air sys-
tem, equalizing the differential pressures
so established within the car. Consider-
ing the fact that refrigerator cars as
constructed are by no means air tight;
that to effect any change in such rolling
stock, even to a slight degree, would
represent an enormous expenditure, and
of the positive "short-time" allowance

for treatinent, it would seem that the
problem presented is of more than ordi-
nary interest. Owing to the great limita-
tions exacted, the really adequate pre-
cooling station is largely in the minority.

Santa Fe Plant

To minimize the excessive damage oc-
curring annually in the transportation
of fruits from southern California, the

Ha<tcrn destinations. Only occasional
subsequent icing, filling the car bunkers,
is needed en route.

General Plan

The general arrangement of the plant
is shown in Fig. 2. The main building,
comprising the power plant, tank room,
day storage and winter storage, is 511
feet 6 inches long by 132 feet wide. Con-
necting to the winter storage, the pre-
cooler coil chamber and icing dock ex-
tend for a distance of 737 feet 6 inches,
the icing dock proper being 693 feet
long. This gives a full length of 1249
feet for the plant, or approximately one-
fourth of a mile.

The structure is entirely of reinforced
concrete, with interior partitions and tun-
nels of the same material. The building
mav be considered as divided into two

Fir,. I. F.XTi-RiOR View ot- Pi ant

Atchison, Topeka & Santa Fe Railway
Company has erected at San Bernardino,
Cal., a combined ice-manufacturing and
pre-cooling plant which has attracted the
attention of the entire railroad and pro-
duce world. It stands as an example of
the highest type of development of cur-
rent-day precooling work, and is the
most efficient station of its kind in ex-
istence. The Gay precooling system is
employed, having been installed under
the direct supervision of the designer
C. M. Gay. of Los Angeles.

Located in the center of the citrus-
fruit district, the plant has been in con-
tinuous service since its erection, early
in 1910. Pick-up trains are operating
throughout the entire San Bernardino
valley, are taken to the precooling sta-
tion as fast as loaded, and, after a dels;'
of about four hours, proceed to their

portions, one devoted to ice manufacture,
the other to precooling. A reinforced-
concrctc reservoir has been built, partial-
ly underground. 30 feet away from the
power-house end. It is HO feet square
by 10 feet deep and is used in connec-
tion with an ammonia-condensing sys-
tem of the two-coil double-pipe type,
which is placed over the front section
of the basin coincident with the plant.
Adjoining this a pump house has been
erected for the ammonia system, consist-
ing of two circulating pumps, otie steam
and the other electrically driven. There
is a transformer station on a line with
the pump house, and a crude oil tank,
20\.«)xlO feet, has been consfucted sim-
ilar TO the water reservoir and parallel
to the boiler room.

Water for the system, including ice
manufacture, is obtained from an ar-

756

POWER

November 14. 1911

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November 14. 191 1

POWER

757

tesian well, which is connected to the
resen'oir by a 14-inch steel-pipe line.
This is at the surface of the ground at
the well end, and enters a measuring
weir at the basin end approximately 4
inches below the edge of the reservoir,
giving a gradient of but 1 per cent. The
flow from this well furnishes a supply
of 500 gallons per minute, the normal
flow being increased to this extent by
an air lift, for which purpose a 4-inch
air line is placed in the same trench with
the water line. The pumps for this

chutes, a Stevenson refrigerator door
and the usual storage-plant auxiliaries.
It has a daily capacity of 900 tons of
ice, when blocks of 300 pounds each are
placed on end in one tier.

The winter storage is divided into four
compartments by 6-inch concrete parti-
tions, giving a storage capacity of about
7000 tons for each such section. Each
room in the winter storage is provided
with an endless-chain ice elevator for
storing, and having an iron ladder for
.Tccess.

the winter storage and carries an endless-
chain ice conveyer which leads from and
through the day storage.

The entire storage plant, including the
brine chamber, is insulated with l'..-inch
double "Nonpareil" corkboard, with an
asphalt finish 1 ' ,■ inches thick on the
floors. The roof is insulated with
"Linofelt" and air spaces. Neither room
has any outside openings, all ice being
handled through the day chamber and
the central tunnel in the winter-storage
room.

Fig. 3. Tank Chamber

Fig. 4. Fans During Construction

system are located in the boiler room.
Fig. I is an exterior view of the plant.

Ice-manufacturing Plant

The installation comprises three 350-
horsepower Stirling boilers, set two in
a battery and one single. These furnish
steam to two 24x42-inch cross-compound.
Vilter Corliss engines, each direct-con-
nected to one 300-ton, 17x34-inch duplex,
double-acting Vilter refrigerating ma-
chine. Adjacent to the engine room is a
36x24-foot forecooler room containing
the forecooler tank, filters and ammonia
receivers, the latter being placed under
the filtering apparatus.

The tank chamber, shown in Fig. 3. is
115 feet 6 inches long, and extends
across the full width of the building,
having a ceiling hight of 21 feet, with the
floor line below grade the distance noted.
The floor is of concrete, covered with
2-inch corkboard over which there is a
finish of r -inch asphalt. Three 75-ton
ice-making tanks are here installed, giv-
ing a total capacity of 225 tons. The
cans used are of the regulation size, llx
22x44 inches, forming ,300-pound blocks,
and are handled, three at a time, by elec-
trically driven traveling cranes. One 300-
ton refrigerating tank is used for the
prccooling system and is equipped with
a Vilter flooded-animonia system of brine
coils, with an accumulator.

Storage Plant

The day-storage room is supplied with
five Stevenson recording double ice

Adjacent to the wall separating the
tank room and day storage, and below
the floor of the latter, is a 49x33x11-
foot brine chamber which is shown
in the sectional elevation, Fig. 5. This
compartment contains a 200-ton, two-
coil, double-pipe brine cooler and three
electrically driven circulating pumps. The
latter are interchangeable, two being
used for the storage plant, or two for
the precooling system, as the conditions

■Roof

Precooler Coil Chamber and Icing
Dock

Connected by the concrete tunnels, the
precooler coil chamber adjoins the winter
storage. It is '44 feet 6 inches long by
48 feet wide and is insulated with 3-
inch corkboard. The installation consists
of a brine coil of 2-inch galvanized pipe,
supported by 4-inch channel uprights
and small angle brackets riveted there-

'Brirte Chamber '

Fig. 5. Transverse Section through Dav-storage ano Brine Chamber

necessitate: by this arrangement it was
possible to omit a fourth pumping unit.
A concrete tunnel fi feet wide leading
from this cooling chamber extends
through both storage rooms. At the end
of the winter storage, the tunnel becomes
a double-deck structure, the added sec-
tion being of like size and construction
as the lower duct, as will be noticed in
Fig. 6. This lower tunnel is used for
the brine mains running to the winter
storage, and to the precooler coil cham-
ber: the upper portion gives access to

to. F.ight double-inlet Sirocco fans, each
about 10 feet in diameter, are arranged
in two banks of four each, as shown in
Fig. 4, which is from a photograph taken
during the course of construction. A
set of four fans, two upper and two
lower on each side, is driven by an 85-
liorsepower motor. One bank is used for
blowing, while the other is for exhaust-
ing, each function being capable of ex-
ecution by either set without reversing
the direction of rotation. A horizontal
concrete baffle, literally a floor, is placed

758

POWER

November 14. 1911

between the two banks, as shown in
Fig. 7.

Leading from the precooler chamber,
two longitudinal concrete tunnels or air
ducts extend to form the main support of
the car-icing dock. These are 7 feet 6
inches and 9 feet 6 inches high re-
spectively, and 10 feet 4 inches wide;
both are of the same length, continuing
the full distance, 693 feet, of the icing
dock. The lower tunnel is the pressure
duct, and the upper the vacuum duct,
both being internally insulated with 3-
inch corkboard. Refrigerating coils of
I'l-inch galvanized-iron brine pipe are
arranged on both sides of either duct, a
total length of about 50,000 feet being
required.

Connecting to these sections by liquid-
sealed revolving joints. No. 18 galvan-
ized-iron pipes 22 inches internal diam-
eter serve as laterals to couple the sys-

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Fic. 6. Section through Winter
Storage

tern to the refrigerator cars. This is il-
lustrated in Fig. 9, which affords a view
of the icing-dock arrangement.

Electric Syste.m

Purchasing electric current at high
voltage from a central station, and step-
ping down to a voltage suitable for op-
eration, the electric system offers no par-
ticular departure from ordinary practice;
that is, the electrical energy is obtained
at lO.OCK) volts and is reduced to 440
volts for motor operation, and again to
110 volts for a three-wire lighting sys-
tem. The alternation of steam-driven and
electrically driven auxiliary machinery, as
previously indicated, permits of a con-
tinuance of operation should trouble oc-
cur at the central station.

Oper.-\tion

The plant has a maximum precooling
capacity of 32 cars. 16 on either side of
the icing dock, in every four hours, or
approximately 150 cars every 24 hours.

The brine is taken from the ice tanks
by the circulating pumps in the brine
chamber beneath the day storage, sent
,through its refrigerating circuit and re-
turned to be cooled by the brine coils in
the same compartment. By this refrigera-

tion of the main ducts, the circulating
air is kept in a similar state throughout
its entire movement except when pass-
ing through the lateral connections to
and from the cars.

A large automatic equalizing valve
connecting the pressure and vacuum
ducts is placed near the terminals of the
tunnels. By regulation of this valve the
pressure of the air delivered to the cars,
and the suction at which it is withdrawn,
are positively governed. The opening of
this valve forms a bypass whenever the
differential pressure becomes excessive,
thus permitting the air to circulate
through the main ducts and main cool-
ing chamber even when no connections
are made for precooling.

.^n automatic intake valve is located
at the extreme outer end of the vacuum
or low--pressure duct, as noted on the
plan. Fig. 2, for the replacement of air
which may be lost from the system by
blowing the warm air from the cars. This

the pressure duct, practically equivalent
at all times to the vacuum below at-
mosphere in the return on the suction
duct. By this method a balanced differ-
ential air pressure directly at the ducts
is obtained without the overcoming of
any frictional resistance in the coil
chamber. The point of equalization of
the air current is thus rendered prac-
tically in the center of the refrigerator
car whenever such connections may be
made. Tests at the plant show that the
differential pressures so equally balance
during precooling as to allow the open-
ing of the refrigerator doors, in the cen-
ter of each side of the car, without any
apparent loss of air to the outside, or
the bringing in of any warm air. al-
though a current of from 6000 to 8000
cubic feet per minute of cold air is
passing through the cars.

Valves fitted to each lateral pipe, open-
ing into both the pressure and the vac-
uum ducts as noted, secure the effect of

Fig.

Showing Baffle between Sipply.and Exhai'st Tunnels

is regulated to open when the vacuum
falls below the differential pressure at
which the equalizing valve is adjusted.
The fresh air so taken into the system
travels the full length of the suction duct,
through the precooler coil chamber, and
if then delivered to the high-pressure
duct to be distributed through the cars.
This insures the proper cooling of all
air brought into the system from out-
side sources during operation.

Referring to the fan installation, the
upper bank is used to exhaust from the
low'-pressure duct, delivering the air to
the precooler coil chamber and thence
over the brine coils. The other set
draw's the air from the coil chamber
and discharges into the lower or main
pressure duct for circulation through
the system. The total air so handled is
about 260.000 cubic feet per minute. The
lower duct is held at a pressure corre-
sponding to from '/j to •>4 inch of water
above the atmosphere, and the upper at
a vacuum of ' {■ to 34 inch of water.
Accordingly, the air is supplied to the
former at a temperature of from 8 to 10
degrees, and is returned through the
latter at a temperature varying from 20
to 24 degrees.

The fundamental principle of the Gay
ssstem is to secure a balanced circuit
with the pressure above atmosphere in

cross connection and reversal of cur-
rent, without any interchange of the
laterals. These valves are of circular-
disk type and of heavy construction. By
employing the liquid-sealed revolving
joints, universal horizontal adjustment is
obtained for connecting the laterals to
the refrigerator-car openings. In this
manner the union can be made to an

Fig. 8. Section through Precooler
Air Duct

entire train without uncoupling or spot-
ting of cars, and regardless of their
various lengths. The closing connection
between the lateral air pipes and the
cars is accomplished by a bellows spring
and scissors-lever joint, comprised of
leather and iron rings, operated by a
crank, as will be seen by reference to
Fig. 9. This preser\'es the entire area
of the pipe under any adjustment and
makes the connection air tight almost

November 14. 1911

POWER

instantly. The pipes themselves are ab-
solutely air tight, being externally in-
sulated with two layers of ■'4-inch hair
felt, suitably covered. By means of the
universal joints they swing free of the car
track when disconected. No telescope con-
flections are employed in this system and
no internal valves, the valves used be-
ing visible for constant inspection.

In practice the cars are connected as
shown in Fig. 10. A funnel is placed
over the bunker opening and the pres-
sure air duct is first connected to the
car for about 20 seconds. The cold air
rushing in quickly displaces the warm
air and vapors cast off by the fruit;
these vapors are allowed to escape
through the ice-bunker trap door at the
opposite end. The lateral from the suc-
tion duct is then joined to the ice-bunker
opening at this end of the car. and cir-
culation is established. During the
cooler seasons of the year both con-
nections are made simultaneously. The
differential pressures, of course, control

through the day and winter storage. Here
it may be diverted or carried on to the
dock, the conveyer traversing the full
length on both sides and making the ice
accessible for immediate loading.

The plant is provided with facilities
for metering all the brine used in pre-
cooling. and in cooling the ice-storage
chambers, also with thermometers giving
the temperatures at all such places.
Barometric columns are installed in the
main air ducts and laterals, showing the
pressure at which the air is circulated
and returned. To afford a complete re-
frigerating record on ever\- car handled,
the velocity of air in both feed and re-
turn laterals is measured.

A brine system of refrigeration has
its advantages in precooling work. Dur-
ing the period of changing trains and
other intermissions the plant is given an
opportunity to store up cold brine, plac-
ing it in a position to properly handle
the large refrigerating demands made
when a full load is incurred. The origi-

A Timel}- Rescue

Bv D. L. F.\CNAN

I had just finished putting in a 100-
ton refrigerating machine. The plant
had been tested and accepted, and the
erecting engineer and myself were ready
for the return trip. It was about four
hours until train time, so we decided to
visit a brewery where machines had been
recently installed. While looking over
the plant a boy ran up to us and cried:
"The ammonia has busted!"

As we rushed to the engine room the
lad told me that the engineer was in
alongside the tanks (the receivers were
m an alleyway by the side of a brine
tahkl. I grabbed an old" jumper and
wetting it in a barrel which stood near,
started for the passageway. Groping
around. I got hold of the engineer and
dragged him to the door. He had inhaled
the green ammonia and was unconscious.
I soon had to drop my hold, but the
erecting man came to my assistance and

Fig. 9. Shovsing Method of Attach.ment to Cars

Fig. 10. Car During Prkcooling

the speed with which the air passes;
the violence of the current permeates to
the center of ever>' package, which is an
essential consideration in proper pre-
cooling.

The total amount of refrigeration con-
sumed by a car of fruit averages about
3 tons, or I ' j tons ice equivalent, de-
pending upon the initial temperature of
the fruit, which, varying with the sea-
son of the year, may cause this amount
to become as low as I ' .• tons or as
high as 4 tons. The amount of air cir-
culating through each car in a period
of four hours approximates I ' .• million
cubic feet. ^X'hen the plant is running
at maximum capacity the amount of air
circulated through each car p - minute
is about 8000 cubic feet, with an aver-
age loss not exceeding .S per cent. The
cars are cooled to about 40 degrees Fah-
renheit.

For icing the cars, upon the com-
pletion of precooling, or for such cars
is are not precooled, the ice is handled
by the endless-chain conveyer running

nal charge of ammonia at the Santa Fe
plant was about 13,000 pounds, and dur-
ing its period of operation this has been
added to hut slightly.

The plant represents an investment of
about S900.000. The special features of
the system installed are the combination
of an ice-manufacturing and precooling
plant in the same structure, the avoid-
ance of loss of refrigerated air either
by leaking out of the car, or by drawing
outside air into the car, and the applica-
tion to one or more cars at the same
time with identical treatment, with the
addition of effecting the precooling ser-
vice without any alterations in the stand-
ard refrigerator car.

The writer desires to mention the
courtesy of the Santa Fe Railway ex-
tended in an inspection of the plant and
the information accorded by C. M. Gay.

The Cunard liner "Aquitania" when
completed will be 86.S feet long, exceed-
ing the present largest steamship, the
"Olympic," by 12 feel 6 inches.

the engineer was finally pulled out. His
hands, face and eyes were burned, and
his chest was dripping with clear am-
monia. Some vinegar was found and
dashed in his face, mouth, eyes and
over his chest and hands; then cold
water was poured over him. When it
was seen that the man was recovering,
it was up to us to stop the leak.

As we did not know what had hap-
pened, it was decided to shut all the
valves. This was no easy task as the
odor was unbearable. In a few moments
all valves on the condensers, liquid lines,
expansion coils and section lines from
the cellars were closed. When it was
possible to get into the room where the
accident had occurred a siillson wrench
was found on the floor; the engineer in
attempting to screw down a valve nut
had stripped the thrtads. Barely two
threads had been caught properly, and
the strain was ton much. He had also
placed one ring of packing loo many in
the valve during erection. Nearly half'a
drum of ammonia was lost.

POWER

November 14. 1911

The Impro\ecl Glafke Oil
Burner

It is claimed by its makers that the
improved Glafke automatic vacuum oil
burner is the only one on the market
which requires no pump. This burner
is designed On the ejector principle; the
oil condenses part of the steam, thus
creating a vacuum in the suction line by
which the oil is lifted from the storage
tank.

The steam supply to the burner, and
hence the quantity of oil fed to the fur-
nace, is regulated by the steam pressure
in the boilers. The manner in which
this is accomplished is shown in the
accompanying figure.

The oil-suction line is at A and the
steam-supplS' line at B. The steam is
admitted to the mixing chamber through
the double-ported valve C. The stem of

fP7)at fhcin-
veniorand thetnanu-
fycturer are doing to save
time and money in the en-
gine room and power
house. Engine room
news

supply valve, thereby reducing the
fire.

The operation of the burner is regu-
lated by changing the tension of the
spring by means of the thumb screw G.
Once the burner is adjusted it requires
no further attention.

The auxiliary steam nozzle H serves
to better atomize the oil and to produce
the lifting vacuum more quickly when
starting up. The steam to this nozzle is
regulated by the valve /.

Connell's Automatic Receiver,

Steam Drum and Water

Heater

The combined automatic receiver,
steam drum and water heater illustrated
herewith was designed with a view to
economy of space and for this reason it
is especially adapted for use in the plants
of office buildings, hotels, hospitals,
apartment houses and similar buildings
where available space is often limited.
The heater supplies v.-ater for boiler feed,
house service or any other purpose as
desired.

Exhaust or live steam, as the case may
he, is admitted at the back of the steam
drum F after passing through the sep-
arator C. The relief valve £ prevents
the pressure in the drum from exceeding
the predetermined degree. Connection to
the house-heating system may be made
through valve D when desired.

The condensed steam falls through the
tubes H into the hotwell G to the botiom

Design of the Glafke Improved Auto.\i.\tic Fuel-oil Burner

this valve passes through a stuffing box
and connects with the diaphragm D.
The spring E acts upon this diaphragm
on one side and the full steam pressure
of the boiler, admitted to the diaphragm
chamber through pipe F, on the other.
Thus, as the boiler steam pressure de-
creases, the spring acts on the steam-sup-
ply valve, causing more steam to be ad-
mitted to the burner, which in turn in-
creases the quantity of oil fed to the
furnace. As the boiler pressure in-
creases it tends to overbalance the pres-
sure nf the spring and close the steani-

The following are some of the points
claimed for the Glafke burner by its
manufacturers, the Glafke Companv, 168
Second street, San Francisco, Cal.:

Exceptionally low cost of installation
due to the elimination of the oil pump
and the extra piping it requires. A sav-
ing in the maintenance and in the quan-
tity of steam chargeable to the burner
system for the same reason. Automa-
tic, close maintenance of predetermined
boiler pressure for wide range of load.

The burner Is sold under a broad
guarantee.

Connell's Receiver and Heater

of which connections are made with the
boiler-feed pumps. The part K con-
stitutes the water heater. The cold water,
supplied from either the house tank or
the city mains, enters through N. The
hot water for the house service leaves
through connection M and the returns
enter through V. Makeup water for boiler
feed is supplied to the hotwell through
the connection L. There is an atmospheric
float arrangement at X which if it is
desired may be connected to a suitable
valve in L so that the makeup water will
be supplied automatically.

November 14, 1911

POWER

761

Besides its simplicity and the economy
in space which it effects, it is claimed
that this apparatus makes the best and
most logical use of the steam because
the steam always comes in contact with
the hottest water first. The apparatus is
manufactured and marketed by its in-
ventor. John F. Connell, 324 Stimson
building, Los Angeles, Cal.

Macdonald Shakiiij^ Grates

The Macdonald shaking grate made by
the Robb Engineering Company, of South
Framingham, Mass., is so designed that

tion, the spaces betweer* the grate sec-
tions at the end of the stroke are exactly
the same as at the beginning, and dur-
ing the whole movement there is prac-
tically no variation in the size of the
spaces.

This grate is made up of small remov-
able sections which securely fit the rock-
ing bars and can be easily removed. These
sections can be furnished with any de-
sired air space and can be replaced, when
it is advisable to change the grade of
coal used, without altering the rocking
and supporting bars or operating mechan-
ism. When necessar\-, a few sections

ment unlocks the grate. Unlocking the
bell crank so that the grates may be
shaken locks the operating lever, and the
only position in which the cam may be
thrown down so as to disengage the
lever is when the grates are level.

.\ remarkably quick piece of repair
work was recently done by the Harris
Engineering Company, of Providence,
R. I. About 1 1 a.m., Friday, they were
notified by the Akela inills, of Pascoag,
that the frame of their engine had broken.
A man was at once despatched to Pascoag,
where he found the large two-ton frame
casting in the engine, a Harris-Corliss
of 200 horsepower, broken. The engine
had been running with a heavy load for
35 years. Fortunatelv the Harris com-

FiG. 1. Grates Tilted and Locked in Flat Position

Fic. 3. Locking Device

the tilting of the sections improves com-
bustion by giving a maximum irregularity
of surface for breaking up clinker and
the mass of unbumed fuel, but does not
open up wide spaces which would allow
unbumed coal to fall into the ashpit. The
detachable top sections may be easily
changed for altering the air openings or
for renewal. When in an operating posi-
tion the grate is flat and is locked in
place, as shown at the left of Fig. 1. The
surface of the grates cannot be left un-
even with points projecting into the fire
for it is only when they are level that
the lever can be disengaged.

To give greater irregularity of surface
the points of the triangles are made to
penetrate deeply into the body of the
fire, thus allowing proper air circulation.
The mechanism is so arranged that when
the lever is operated the top surfaces of
the triangular sections are (iO degrees
from the horizontal, as shown in Fig. 2.
and the lever can be swung through an
arc of about 60 degrees. Because of
the equilateral-triangle construction of
the sections and the fact that the tilting
of the sections is entirely in one direc-

may be replaced without renewing the
whole grate when perhaps only a small
part is burned out. This design minimizes
the cost of repairs and permits keeping

pany had an old engine of that type on
the floor of its plant, and the frame
was taken from it, placed on a five-ton
automobile truck and taken over the 25

F i>.. 2. How Triangular Section Can Be Tiitec

the grates in their best working condi-
tion.

This grate is locked in a horizontal po-
sition and cannot be moved until the
shaking lever is inserted and locked in
place, as shown in Fig. 3, which move-

miles of road to Pascoag. At midnight
Saturday the machinist was taken to
Providence by automobile to get some
fittings, returning at daylight, and the
engine was ready to start up Sunday
morning.

762

POWER

November 14, 1911

" Anybody who can wnlc. can
write an advertisement. But the
question is whether it will sell
anything or not," was the state-
ment of one of the biggest general-
magazine advertisers of the coun-
try the other day.

Is this a fact?

Is a set of rhymed words that
looks like a poem when printed on a page, but that
never stirs anyone to an iota of feeling, a poem? Is a
brain which never thinks, a brain? Is a salesman who
never sells anything a salesman?

We don't think so; neither do we think a half-page
or a page or a double page of words about something
that is to sell, but which never induces anyone to
buy it or investigate it, an advertisement.

An advertisemen means at core a thing that
makes somebody iitrn to something.

If the advertisement is worth its name, it will
iitr)i certain people who are interested in that class
of goods to the jiarticular representative of that class
it refers to. It turns them because it makes them
see in that product some certain characteristic that,
they think, would constitute it their most profitable
investment. And if the investigation verifies this
impression, such "tumings-to" mean sales.

That is an advertisement.

And herewith another thing becomes apj^arent:

A real advertisement cannot be arittcn about inferior
goods.

When you see an advertisement, so called, that
is all vacuous general statements, you can be sure
of one of a brace of things ;

Either the subject under discussion won t bear
scrutiny.

Or the author of the copy didn't know how to
write an advertisement.

Vou can't go to particulars about goods whose
makers have spent most of their time in building up
the glossed-over impression that their goods are as
good or better than the next man's "because they
are." It is the particulars behind the "because"
that the latter-day buyer is wrap|)ed up in.

Particulars sting down to those little differences,
and to the hit:, differences ahich the little ones hide, that
a])peal to the man who thinks before he acts, and
who pays small attention to an advertisement that
does not make him think. Such a man is quite apt
to believe that " wide-as-the-skj' " statements are
the refu"e of the la<?!;er.

foots the

( )f course they may not be.

Poor advertisements can be
written about good products, and
those same goods sell mightily,
too. They may have no compe-
tition, or no competition at all
in cjuality, or • else the sales
may be impelled by costlier ways
of publicity for which the buyer
)ill in the end.

All this gets us to our point: —

Power advertisements not only tell the truth,
&«/ most of them tell it so as to bring action.

"Two and two make four" is true enough; but
its repetition has no value — it doc's nothing.

"This machine is right for you because it is this
and this, and this, and does this" — that can he both
true and be written in such a way as to create instant
desire to see, to investigate, to buy that machine.

We, the Service Department men who write
Power advertisements, are trained to take advan-
tage of this one big opportunity — that, in the case of a
specialized paper like Power, every individual of
our multiplied jjrint-salesman goes direct to a buyer or
a person concerned or interested in the bm'ing of the
thing advertised. We know ever\- lost word may
mean a lost sale.

\\'e write these advertisements fully as much
to serve vou as to ser\-e the advertiser whose goods
they describe. There is where the full idea of "ser-
vice" comes in.

When we put together a convincing advertisement
that turns you to investigate something in Power
Selling Section and then, quite likely, to buy that
thing, we perform a service for you by getting you
to as efficient, or the most efficient machine, appli-
ance, whatever it be, that the market can give you
• — without the " exploration- worry" on yoiir own part
after a thing that is at tmce reliable and suited for
the immediate purpose.

Power advertisers hand over to us the writing
of their advertisements because they feel we can do
it most effectively; they give iis their confidence.

And just as this confidence is thro^\■n to the winds
unless we v.TJte these advertisements effectively, con-
vincingly, so this effectiveness goes to the Avinds un-
less the advertisements are read.

Power advertisements are for >-ou, and when you
read them and act on them, you serve yourself.

\\>\. u

NKW ^ORK, \()\ KMHF.R 21, 1'

No. 21

N

OTHIXG on this footstool stands still; in fact.
the stool itself does not stand still.

Even-thing either goes ahead — progres.ses — or
goes back — retrogresses.

The child, progressing froni total heljilcssncss,
creeps, then walks erect.

llie orphaned egg retrogresses from a sweet and
wholesome article of diet at first, tlirough successive
stages of increasing strength, tmtil it l)ecomes at last
a loud and boisterous outrager of the noses of all who
are not afflicted with a cold in the head.

Ever>-where, in cverv-thin
progress or its opposite;
there is no standing still.

and ever)'i)ody, is

There may be an aji-
parent standing still, but
close investigation will
show that in reality
there is either i)rogress ot
retrf)gression. An idle
steam engine is not actu-
ally standing still except
in the dynamic sense of
the word ; it is daily grow-
ing more ribsolete and,
hence, its selling value is continually decreasing.

Wine lying idle in the cask is idle onlv in the
physical sense. If left tmdisturbed long enough, it
will lieconie so rich and mellow that its bibbers will
declare it of immortal vintage.

In all science progress is the rule, because each
new pioneer takes uj) his work at the pf)int where
his predecessors left off. If this were nfit sfi, civili-
zation cfjuld not \x.

Each generation would have to fabricate its own
language, develop its own arts, industries, etc.

Because of the continually accelerating progress
in scientific knowledge, we are able to cross the ocean
in that man,-el of engineering effort, the steamshij)
"01}-mpic," within a hundred and four vears after
Fulton succeeded in making the "Clermont" paddle a
wheezing four miles an hour on the Hudson river.

The progress in steam engineering during the
last few score of years has been botli rajjid and wonder-
ful.

The truth of this is very forceftilly illustrated
by two articles in this issue. One is descrijnive of
Philadel])hia's veteran
steam engine and the
other (if the New York
Edison Cf)m])any's new-
est turbine generating
unit. It is a big, big
jump from a i2j-horse-
]iowcr machine to one
whose normal capacitv is
placed at 20,000 kilo-
watts or sfmie 26,666
i, horsepower. Yet this
jump has Ijeen made
within the space of sixtv-
r years, a period less than man's allot fetl span of

fou
life

The thoughtful perusal of these two articles
slvitild be as good as a scnnon basetl on the j>arablc
of the ten jiieces of money.

.Surely, many men have inrrcasefi their one
potnid's worth of knowledge anrl ability In five and
ten jMPimds" worth ere such impressive strides wore
finally bwnight within the limits <<f accomplishment.

P O W E R

Novemter 21, 1911

Witherbee-Sherman's New Station

Witherbee, Sherman & Co.'s central
electric-power plant is situated in the
western part of Mineville, N. Y., and its
power, together with that generated at
the Port Henry plant, described in a
previous article, and that of two hydro-
electric stations nearby, is used to op-
erate the magnetite mines of the neigh-
borhood. The building is of red brick
with steel trusses and corrugated-iron
loof. The main structure is rectangular,
96x55 feet and 30 feet high, with an
additional boiler-room extension 30x55
feet. All the floors are of concrete and
the building is practically fireproof. A
concrete transformer house, 28x18 feet,
joins the power house. The engine-
room floor is 14 feet above the boiler-
room floor and 9 feet above the engine-
loom basement.

Boiler Equipment

The boiler room is 45x81 feet, and
contains three Geary water-tube boilers
and one Babcoclc & Wilcox boiler. Each
Geary boiler is rated at 250 horsepower
and contains one hundred and sixty 3' j-
inch tubes 14 feet long, with water
drums 42 inches by 18 feet. The grate
surface of each boiler is 55 square feet.
The Babcock & Wilcox boiler is rated at
400 horsepower and has 4000 square
feet of heating surface which consists of
three steam and water drums, 36 inches
by 23 K? feet, placed above and con-
nected to a set of 21 sections of tubes,
each section consisting of nine 4-inch
tubes 18 feet long. The grate surface
of this boiler is 90 square feet. Each of
these four sets of boilers is provided with
McClave sectional, top-shaking grates,
fitted with twin levers for divided cutoff
movement. The boilers are also provided
with Wing turbine blowers for forced
draft. The Babcock & Wilco.x boiler is
equipped with two 20-inch blowers, and
the Geary boilers each have one 20-inch
blower, all side installed. A Davis regu-
lator is used in connection with the Wing
blowers.

The feed water for the boilers is sup-
plied by a 10x6xl0-inch Knowles pump
of the outside-packed plunger type. A
second feed-water pump, a 10x6xl2-inch
Dean, outside-packed, plunger type, is
held in reserve. These pumps are placed
one at each end of the boiler room.
Boiler water is obtained from a pond fed
by the Dalton reservoir, 3 miles north of
Mineville. The feed water is heated by
a Cochrane, open-type, feed-water heat-
er, placed directly back of the boilers.
Two pumps supply water to the Cochrane
heater; one is a Knowles 7x5-inch and
the other an Alberger 2 '/.-inch volute
pump, run by a 5-horsepower motor, and
taking water from the condenser in the
engine room.

By Guy C. Stoltz*

and Samuel Shapira f

.4 modern plant supply-
i)ig electrical energy to op-
erate magnetite -mines in the
neighborhood of Minei'ille,
N. y. -4 large recipro-
cating engine and mixed
pressure turbine with a
com,hined maximum output
of 1500 kiloivatts drive the
generating equipment.

'( lii.-r tMiKilu-.-r. Willleliji'.'. .-^heiluaii ,V l_...,
Mineville. X. Y.

tMininj; engineer. Witborbee, Sherman &
Co., Mineville. X. Y.

Saturated steam is led from the boil-
ers through 8-inch extra-heavy U-pipes
to the steam chests of the Nordberg
Corliss engine. \ 6-inch extra-heavy
pipe line extends to the steam chest of

is received from the Lake Champlain &
Aloriah Railroad over a timber trestle
348 feet long, which has an open con-
crete-storage bin of 2500 tons capacity
underneath. Ashes are delivered by the
.McCIave-Brooks system of scrapers to
an outside pit where they are loaded by
bucket elevator to a concrete storage bin.
From the bin the ashes are drawn off in
wagons and used for road building.

Turbine Generating Equipment

The engine room is 44;jx52 feet and
all the engine auxiliaries, except the ex-
citer and switchboard, are placed below
the engine-room floor. The generating
apparatus consists of a Nordberg hori-
zontal, cross-compound, condensing en-
gine with cylinders 23 and 46 inches and
48 inches stroke, and a horizontal, mixed-
pressure turbine. The Nordberg engine
develops 1000 horsepower at 150 pounds
pressure and 100 revolutions per minute.
v. is direct-connected to a flywheel al-
ternator rated at 750 kilowatts, 94 revolu-
tions per minute. 3300 volts. An ex-
citer is belted to the alternator shaft.

I

Fig.

Exterior View of Mineville Pl.\nt

the low-pressure turbine. All saturated-
steam pipe lines are covered with as-
bestos fire-felt covering of standard
thickness.

Smoke goes to the stack through a
5'/x7-foot steel breeching. The unlined
steel stack, which is outside the build-
ing, is 7 feet in diameter and 110 feet
high, is self-supporting and rests upon a
solid-concrete foundation 17x17 feet and
9 feet high.

The boilers are hand fired with No. 2
buckwheat anthracite coal, which is de-
livered to the boiler room by an over-
head track supported by concrete posts
8 feet above the boiler-room floor. Coal

The low-pressure turbine is of the
horizontal Curtis type, designed to run
condensing, and rated at 750 kilowatts.
It is run on the exhaust steam from the
Nordberg engine. When operated on
live steam at full rated load with not
more than 2 inches absolute back pres-
sure in the exhaust chamber of the tur-
bine, and with a gage pressure of 150
pounds at the throttle, the consumption
of dr\- steam does not exceed 26.5 pounds
per kilowatt-hour. The turbine develops
520 kilowatts on the exhaust steam from
the engine, when the latter is* carr»-iis
a load of 650 kilowatts, giving an oi'trut
from the combined units of 1170 kilo-

November 21, 1911

POWER

765

watts at a water rate of 18.05 pounds per
kilowatt-hour at the switchboard.

If necessar>', the output of the two
units can be increased to 1500 kilowatts
by admitting additional high-pressure
steam into the turbine. In case of ac-
cident to the engine, it can be shut down
and the turbine will then carr>- 750 kilo-

magnetite mines. The Kingdom plant
is operated by the flow in Beaver brook,
which has its source at Lincoln pond,. six
miles from Mineville, at 1150 feet eleva-
tion. The pond is supplied by springs,
but principally by the drainage of ap-
proximately 17 square miles of moun-
tainous country.

Fig. 2. Main Generating Unit of 1000 Horsepower Capacity

watts on live steam, with a consumption
of 26.5 pounds per kilowatt-hour, which
is approximately the same as the steam
consumption of the Nordberg engine.
Under ordinary conditions, however, the
turbine operates on the exhaust steam
alone from the engine.

The exciter used in connection with
the turbine consists of a 50-horsepower
induction motor and a generator rated at
35 kilowatts. An equalizer rheostat is
used between the field of this exciter and
the exciter used with the engine-driven
alternator.

The Curtis low-pressure turbine rests
upon a rein forced-concrete platform 18
x8xl foot, supported by six reinforced-
concrete columns 12 inches square and
13 feet high. The reinforcement for the
platform consists of 10-inch I-beams and
8-inch channels, the reinforcement for
each column being six strands of Ij-
inch wire rope. The space beneath the
platform is used for the turbine auxil-
iaries, consisting of an Alberger con-
denser having a condensing surface of
4500 square feet; an 8 and 20 by 12-inch
dry-vacuum pump, and a 12-inch stand-
ard volute pump having a 14-inch suc-
tion. The condensed steam is delivered
ty an Alberger 2''. -inch volute pump
to the feed-water heater in the boiler
room.

HVOROELFXTRIC PowKR STATIONS

The two plants here described are
owned by D. F. Payne, of Wadham Mills,
N, Y., and furnish power for adinining

The power house, a wooden structure,
is situated one miles from the pond. A
concrete dam above the plant delivers the
v.ater under a head of 316 feet througli a

plant at Mlnevnie, where three single-
phase, oil-cooled transformers step the
voltage down to 3300.

The Wadhams plant is situated on the
Black river, six miles east of the King-
dom plant. The overflow from Kingdom
dam and the discharge from the Pelton
wheel, together with the natural drainage
lunning to the river, are stored at this
plant by a concrete dam. The power
house is equipped with a 300-kilowatt,
0600-volt alternator, belt connected to a
turbine operating under a 48-foot head.
The penstock from the dam is 54 inches
dfameter and 350 feet long. Excitation
for the generator is provided by a 7!j-
kilowatt generator belted to the main
shaft.

The current at 6600 volts is transmitted
nine miles to the Cook shaft station at
the Smith mine, two miles north of Mine-
ville proper. Here the voltage is stepped
down to 3300 by oil-cooled transformers
connected in delta. From the trans-
formers the power is delivered to the
central plant at Mineville.

Power Distribution

The transmission lines from the Port
Henry plant, carrying 2300 kilowatts at
6600 volts; the lines from the central
plant, carrying 2175 kilowatts at 3300
volts; and the 675 kilowatts from the
two hydroelectric plants have their bus-
bars so connected at the A & B dis-
tributing station that any one of the
plants may be operated on any of the
feeder lines, or they may all be run in

Fir,. 3. Mixed-pressure Turbo-generator

.12-inch steel penstock to a Pelton wheel
tunning at .^00 revolutions per minute,
direct connected to a 37.S-kilowatt. 6600-
volt alternator. An ll-kilowatt. 125-
volt exciter is belted to a pulley on the
main-generator shaft.

Current for power at OflOO volts is
transmitted seven miles to the central

parallel, the voltage being maintained by
means of a regulator on each generator.
At the main distribution station the
lines are connected through automatic
overload oil switches to the 3.'<00-volt dls-
trihutlne busbars of an It -panel switch-
board, of which there are two panels for
4fl2-hnrsepower synchronous motors

766

POWER

November 21. 1911

driving two 2SO0-cubic foot compressors;
two for 200-horsepower motors driving
two 1200-cubic foot compressors; two for
the lighting of Witherbee and Mineville;
one panel for a 12-horsepower motor
driving one vertical triplex pump in A
shaft; one for a 30-horsepower motor
driving one horizontal triplex pump in
B shaft; one for a 300-horscpower motor
driving a Wellman-Seaver-Morgan four-
drum hoist; one for motor drives at con-
centrating mill No. 1 ; and one for motor
drives at concentrating mill No. 3. All
power from the switchboard at the main
station is delivered at 440 volts, except
to the lines for the synchronous motors,
and those for mills Nos. 1 and 3, which
receive power at 3300 volts. At the mills
the current is stepped down to 440
volts.

One of the synchronous motors is belt
connected to a 2500-cubic foot Nordberg
30 and 44 by 48-inch two-stage air com-
pressor. The second motor drives in
like manner an Ingersoll-Rand two-stage
compressor, \8' 4 and 30'4 by 27 inches.
The synchronous motors have recently
leplaced the induction type in order to
realize a higher power factor and to ob-
tain better regulation. These motors are
operated with an input of 360 kilovolt-
amperes and 80 per cent, leading power
factor. Both motors are rated at 400
horsepower at 3300 volts, and are ex-
cited by direct-connected exciters. They
are started as induction motors at 1650
volts, and when the speed is near
synchronism they are connected directly
to the 3300-volt lines.

Two 1200-cubic foot IngersoU-Rand
16;4 and 18' | by 25-inch two-stage com-
pressors are belt connected to two 200-
horsepower, 440-volt induction motors.
\ Wellman-Seaver-Morgan four-drum
geared hoist for A and B shafts of the
Harmony mines is driven by a 300-horse-
power induction motor. Three oil-cooled,
single-phase transformers are provided
for the smaller compressors, three-phase,
oil-cooled for the pumps, and one three-
phase, air-cooled for the hoisting equip-
ment.

Transmission System

The main transmission lines leading
from the central plant to A & B dis-
tribution station are tapped by sublines
vhich lead to mill No. 2, where the 3300-
volt current is transformed to 440 volts
and distributed through a three-panel
switchboard to the various motor drives.
A second set of branch lines carries
power to the .Joker & Bonanza hoisting
house, delivering it to busbars from which
it is distributed to the several transform-
ers through a panel switchboard and
thence to a two-drum hoist geared to a
500-horsepower induction motor, and also
to a 1200-cubic foot Ingersoll-Rand com-
pressor, belt driven by a 200-horsepower
induction motor. A third set of sublines

carries 3300 volts to the Barton Hill The Chief's Pav

mines, through transformers reducing

3300 to 400 volts, and delivering to an Ky H. M. Phillips

electric tram, an auxiliary hoist and a

_- . ■ J .• _ . J ■ • The A. & B. plant was experiencing

75-horsepower mduction motor driving ^ . '^ , , , ,

, 11 r> J 1 » ran u- 016 "' "s protractcd shutdowns. In
an Ingersoll-Rand two-stage, 650-cubic

r ^ A r iu 1 1- V order to avoid total disorganization of its

foot compressor. A fourth set of lines , . „ ^ , ,.

_ , working force a favored few were al-

carries the usual voltage to the Cook , . r • ^ ,. j j

, , , . , , c- ■ , ■ ' lowed to remain on the payroll and do a

shaft hoist station at the Smith mine, . ,, . , , ; r ■_ .o

... , full day s work, on repairs, etc., for half

where, after being transformed, it is de- „.,,, . ^. ,.„„,,,„ „„ .„ ,,« ,^r. ™^^

' Jt , ... pay, their regular pay to be resumed

ivered to two 75-horsepower induction u .u i . u u ■ u •

^ „ J ^..„ when the plant should again be in active

motors driving two Ingersoll-Rand 650- ^p^.^.j^^ ^s there was no other chance

cubic foot compressors, to one motor ,^^ employment in the vicinity, this

thriving a 100-horsepower, NVellman- ,((,^^3, ^pf^^ ^.^^ accepted with more or

Seaver-Morgan two-drum hoist, and last- ,^^5 enthusiasm, bv those who did not

ly to a 30-horsepower motor driving a ^.^^e to move; among the fortunates was

vertical triplex pump near the sump at j^^ ^.^jef engineer of the plant. As the

the foot of the Cook shaft. time for starting up approached, exten-

The compressor installation at the A & ^[yg alterations and repairs were rn order,

B distributing station, together with the many new men were taken on and, of

auxiliary compressors at the other hoist course, these had to be paid at, or near,

houses, consumes the greater part of the the rates prevailing in other plants, al-

power generated by the four plants. The though the old hands, much to their

total air equipment, which includes sev- dissatisfaction, still remained on half

eral emergency, steam-driven compres- pay. One of the new members was a

sors, can deliver about 12,000 cubic feet machine-shop foreman who, upon the

of free air per minute at 85 pounds gage death of the old chief, applied for and

pressure at the machines. obtained a temporary appointment as

An electric-locomotive haulage system chief engineer, pending a definite ar-

is installed in the Joker & Bonanza mine, rangement for filling the position. While

the tram cars being dumped at the acting in this capacity he had an in-

shaft pockets by electrically operated teresting experience with an engine gov-

tipples. ernor which furnished considerable

amusement but probably prevented his

Cost of Power receiving the permanent appointment, .^t

In 1910, the average cost of power 'he end of two weeks he returned to

from the four generating stations per '"^ machine shop.

kilowatt-hour was ,S0.009 for operating When the monthly payday came

only, or S0.013 for a total. The cost per around, a very indignant and aggressive

ton of ore mined was .S0.164 for operating foreman appeared before the paymaster;

only, or .S0.191, including fixed charges, the conversation that ensued was along

The consumption of power averaged 13.8 'he following lines:

kilowatt-hours per ton of ore mined. Foreman: See here, mister; you have

The distribution of load in kilowatt- ■"=>'le a mistake in my pay and I want it

hours during 1910 was: Compressors, '"ade right.

4,797,918; mills, 1,967,776; hoists, 755,- Paymaster: Why, certainly, if there is

599; pumps, 207,031; miscellaneous, a mistake we are here to correct it; let

475,867; commercial power, 575,579; ^^ ^^e your pay slip, please. What is

total, 8,779,800 kilowatt-hours. ^^^ trouble? It looks all right to me.

r- „ ■ r »u , r_ Foreman: It does, does it? Well, it

Comparison of the power costs for . .'

compressing and hoisting at the Harmony ^°°^' ^ ^°f ^^^^ 'T 'l^' '° ""'' '"''

electric plant and at the Joker & Bonanza |'°.^ ^« '^ ^^ ^^^^" ' forgotten seme-

steam plant, showed a saving of nearly ' ^'

-, ^ 1 r • J • f r Paymaster: Come to the point, please,

3 cents per ton of ore mined in favor of , ■ ,, . , , . , .

... r^ c . .u 1 and tell me just what you think is wrong;

the former. Costs for power at the elec- ,.,.., , , ,

,...,. .,„„,^, . . , this slip is the same as last months

trie plant totaled .s0.0451 per ton mined ^ '^ ^ , . ,

and you made no complaint then.

at the steam plant the items were: ^ _ , . , .u .

Foreman: Do you happen to know that

iKiiHTiNC for '\Y0 weeks of this month I was acting

(•,,.,1 .so.n.-.OT chief engineer of this plant, and that

'•"'"";, , : IIn,','IJ Mr. G., the vice-president, told me that

Siiipllps nncl ippnirs ii.00.)3 ' ^ , , .

while I was acting chief I would receive

coMi-uKSSiXG the chief's pay?

', 'Ji',],i, iiliiiiM Paymaster: Come to think of it. I

spppiii's mill lepiiiis o.oiiLM did hear a good deal about the acting

•i-,,i.,i sfTivrnii chief engineer, but the vice-president

said nothing to me about the pay; hence

The steam plant at the Joker & Bo- i have no authority to change your regu-

nanza mine is now being replaced by an lar rate. He is away now. but will be

electric hoist and electric-driven com- back in a week or 10 days and if \ou

pressors. wish I will speak to him about it.

November 21, 1911

POWER

767

Foreman: I want the money now. Mr.
G. told me, and I reckon that what he
says goes around this plant. You will
fix that up, and do it quick, or you will
wish you had after I see him.

Paymaster: I don't want to get into
any trouble with Mr. G. — he is a friend
of yours, I hear — and if he told you so
I suppose it must be all right.

Foreman: He did tell me, I have told
you before, and it is all right; so get a
move on.

Paymaster: You know I hav-e no real
authority in the matter, but still if Mr.
G. said so —

Foreman: I tell you he did.

Paymaster: It must be all right.

Foreman: It is all right.

Paymaster: All right, then; the chief
engineer was getting 25 cents a day less
than you are.

That ended the argument. Some read-
ers may be inclined to agree with the
foreman's concluding remarks — he did
not know about the half-pay arrange-
ment— -"A man that would do the work
for that pay ought to die."

Surface Combustion in a Boiler

William A. Bone. D.Sc, F.R.S.. pro-
fessor of applied chemistry at the Uni-
versity of Leeds, England, has been visit-
ing the United States for the purpose
of repeating before the American Gas
Institute at St. Louis and at the Chemists
Club, New York, his lecture upon "Sur-
face Combustion," which attracted so
much attention when presented to the
Royal Society this spring.

It has been known for some time that
the gases of a combustible mixture would

Fic. ]. Thf. First Experiment

unite below the lempcralure of ignition.
Hydrogen and oxygen will unite without
any sign of flame at about .S(K) degrees
Centigrade fP32 Fahrenheit) while the
ignition point at which the more rapid
combination generally known as combus-
tion occurs is 5^) degrees Centigrade or
90 Fahrenheit degrees higher. The rate
of combination below the ignition point
is slow, but can be greatly increased
when certain materials, such as porous

.1 combiistihlc mixture of
gas and air, introduced di-
rectly into the tubes filled
with broken fireclay, burns
witho-ui, flame and evapo-
rates 21 pounds of 7i'ater
per square foot of heating
surface. This is about
seven times the usual am-
ount and gives an efficiency
of over 93 per cent.

porcelain, fireclay and some of the metals
are brought within the mass of the com-
bustible mixture. An example of this
is the use of platinum for lighting a jet
of gas.

This stimulation is not confined to the
subignition temperature, but it has been
found that the presence of incandescent

form a chamber into which a mixture of
gas and air in the proportions necessary
for combustion, or containing an excess
of not over 1 per cent, of air, is intro-
duced under a pressure of between ',s
and 'I of an inch of water. The escap-
ing gas is ignited upon the face of the
slab, which soon becomes incandescent.
The flame disappears entirely, and the
combustion progresses at the surface of
the tile or at a depth of not exceeding
' V inch. One can put his hand upon the
casing at the back and Professor Bone
says he could with equal immunity put
it upon the back of the porous slab if
that were accessible.

Such a slab in an inverted position was
held over a dish of silicate of soda in
solution, showing the rapid evaporation
and the solidification of the water glass
by downward radiation onto the surface
of the liquid. A smaller plate was im-
mersed, while the combustion was in
active operation, in a glass jar of car-
bonic acid gas without any diminution
of the incandescence of its surface,
showing that the combustion is inde-

Fic. 2. Section and End View of Boiler

bodies in a burning mixture increases
the activity of the combustion; the com-
bination of its constituent gases takes
place more quickly than when it is not
there, more heat is generated per unit
of time and flame is absent.

Perhaps the best idea of the subiecl
may be gained by a glance at Professor
Bone's first experiment. A frame. Fig. 1,
surrounding a slab of porous refractory
material is closed at the back so as to

pendent of the atmosphere in which it
lakes place. Muffles are made by burn-
ing gas around the retort in a conglomer-
ate mass of finely divided refractory
material.

The most interesting application shown
from the point of view nf ihc power-
plant engineer was to a boiler. From
the report of London Engineering of the
original lecture is reproduced in Fig. 2
the section of such a boiler having \(.

768

P O W F R

November 21, 191 i

tubes, 3 inches in internal diameter.
Each of these has a bush £ of fireclay
and is filled for the rest of its length
viith finely broken refractory material.
At one end these tubes are covered by a
casing which, as is shown in the end
view, is divided into three compartments,
so that either 2, 4, (i, 8 or tO of the tubes
may be used at a time. The casing is
further divided as shown in the longi-
tudinal view into two chambers, C and D.
When starting up, air alone is admitted
to the chamber C by means of the tubes
A and gas alone to the chamber D, by
means of the tubes B. The small tubes
F convey the gas to the centers of the fire-
clay bushes in the several tubes and it is
ignited as it issues from the left-hand or
free ends of the boiler tubes, and the
gas and air supply adjusted until the
flame strikes back and combustion pro-
ceeds in the bed of fireclay. When the
mass has become incandescent the gas
supply to chamber D is shut off and
through the pipes A a combustible mix-
ture of gas and air is admitted. The
separate admission is necessary at first
to prevent the backfiring of an explosive

mixture during the starting-up process,
.^fter combustion is established the com-
bustible mixture can be introduced di-
rect if admitted at a velocity greater
than that of flame propagation so that
the fire cannot run backward into it.

The gas burns without flame in the
front end of the tube, the incandescent
mass being in direct contact with the
heating surface. When such a surface
has to absorb heat from a current of hot
extinguished gas, as from the products
of combustion in an ordinary boiler tube, .
the gas in immediate contact with the
lube becomes chilled and this film of
cool gas prevents the contact of the hot-
ter gases with the heating surface. Be-
ing a very poor conductor, it seriously
impedes the transfer of heat from the
gases to the water. Such a film is, how-
ever, entirely transparent to radiant heat,
and the heat from the glowing mass is
taken up by the water with great rapidity.
Observation shows that about 65 per
cent, of the evaporation occurs upon the
first foot of the tube length, about 25 per
cent, upon the second foot and only the
remaining 10 per cent, upon the last foot.

The evaporation in regular working is
over 20 pounds per square foot of heat-
ing surface, and this can be increased
.nO per cent, with a falling off in effi-
ciency of only 5 or 6 per cent. The gases
leave the tubes at a temperature not
much over a hundred degrees Fahrenheit
above that of the steam, and are fur-
ther reduced by means of an economizer.
The combined efficiency of the boiler
and economizer is over 93.4. Some test
figures follow:

Date, December 8, 1910
Pressure of mixture entering boiler

tubes 17.3 in. H,0

Pressure products entering feed-

watir lieater 2.0 in. H,0

Pressure steam 100 lb. gage

(Jorn-sponditig temperature 168 C. 334 F.

Temp, gases leaving boiler tubes. . 230 446

Temp, gases leaving heater 95 203

Temp, water entering heater 5.5 41.9

Temp, water leaving heater 58 136.4

Evaporat'.on per square foot heat-
ing surface 21.6 lb.

Heat Balance

Gas per pound water at 32** and

atmospheric pressure 996 cu.ft.

Net calorific value 562 B.t.u

Heat supplied to boiler per hour. . 559,830 B.t.u.

Water evaporated per hour 450.3 lb.

Water evaporated from and at 212*

per hour 550 lb.

Heat transferred to water per hour .i27.soo B.t.u.

CostSystem for Power Plant Operation

From tiine to time articles have ap-
peared in the technical press upon keep-
ing shop costs, but these articles have
dealt almost exclusively with the cost
of production of staple machines, arti-
cles, etc., explaining the various systems
devised to show the true profit or loss
and to furnish a foundation on which to
estimate for the future. These systems
are very effective and often result in a
decided saving.

The following, however, describes a
system devised by the writer for the
power and repair plant of Butler Brothers,
Jersey City, to ascertain the cost of up-
keep of the various parts of the equip-
ment.

Some system in all large plants is nec-
essary to keep a proper account of this
cost and the relation between mainte-
nance and repair, without involving much

Bv Charles W. Gill

By means of a card s}'s-
tcui a complete record is
kept of all labor and ma-
terial for both constriiction
and repair 'icork. In addi-
tion to tins, iceekly reports
are made concerning the
condition of all apparatus.

clerical labor. The starting point of this
system is with the "Requisition for Con-
struction or Repairs," shown in Fig. 1.
These cards are filled out by the foreman

of the different departments as to the
work required. They are then sent to the
writer, who gives the job a number; if
new work, an even number, and if re-
pairs, an uneven number. In case of new
work the card is O. K.'d by the superin-
tendent. The job is then assigned to the
proper mechanic and when the work is
completed it is O. K.'d by the workman
and by the foreman in charge of the
department in which work has been done.

On the reverse side of this card is
space for the cost of labor and material
which is entered each day from the work-
men's time cards. This cost sheet is
shown in Fig. 2.

The time card is filled out by the work-
man in the space or spaces according to
the number of departments he has worked
in, he inserting the letter of the depart-
ment in the first column. He then gives

Nrw Work No. r^^^,. No.

REQUISITION FOR CONSTRUCTION OR REPAIR WORK

New Work Aqihorited

Date

Sifl-n^rt.

Pftit nf I .V«^

1

lOUl 1

1

DATS

0

0

1

'

"^VllAMC

1

C.KFEKTERS

__L_

— ; —

—

—

--

—

—

—

—

.LECT.ICAN

PAINTBR

1

—

—

—

—

—

—

—

—

—

—

LU»B«

"■^"•PPUBS

PAINT. .C

H.KD.A.E

1

Fig. 1. Requisition Blank

Fic. 2. Cost Sheet for Individual Job

November 21, 1911

P O V(' E R

769

the nature of the work and the time.
This card is deposited at the office when
he leaves at night. The next morning the
time cards are looked over to note correc-
tions and to mark the items of new work

posited at night. The next morning the
cards are looked over to see if the word-
ing is sufficiently clear to describe what
was done, so that it could be understood
several months afterward. The cost of

Fig. 3. File Cards Showing Work Done on Engines, Boilers and Pumps

or repairs by the number under which
the work is designated. The time is then
transferred to the proper job card. Fig.
2. No attempt is made to keep the in-
dividual account of each man's time, but
instead a division is made according to
the trades. When the work is complete
the total labor cost is easily obtained.

At the time an order is made out for
material it is made in duplicate and the
job number is marked on the carbon copy.
When the invoice comes in for the ma-
terial, it contains the number of the
order, and the price of the material is
put on the duplicate order which, in turn,
is transferred to the card bearing the job
number.

Thus is obtained a record of the total
labor and material for repairs and new
work, but it gives us no record of repairs
on the separate parts of the equipment
unless such be transferred from the time
card. To avoid this there are separate
cards for each piece of apparatus. These
cards are shown in Figs. 3 and 4, and
are given to the workman to fill out with
the time card with which they are de-

labor and material is entered on the bot-
tom and the card is filed away under a
proper heading, each engine, boiler, ele-
vator, etc., having its separate guide card.

need not be preserved after the time is
transferred to the job cards.

It costs very little to employ this sys-
tem and a complete record as to the cost
of repairs and new work is always at
hand. It affords a means of locating the
principal faults in the equipment which,
ty frequency of repair, warrants chang-
ing. It also gives a record of the length
of time one packing lasts over another
on pumps, engines, etc.

A system of weekly reports on the con-
dition of the equipment is also used. Two
forms, Figs. 5 and 6, show the style of
report, the former being made out to
show the condition of all fire apparatus
in the plant. It is well to have these
reports made out by different men al-
ternating each week, as one is a check
against the other. Any trouble with the
.apparatus is immediately repaired so that
the system is always in working order.
The same style of report is used in re-
gard to elevator equipment. Fig. 6, so
that any repairs needed for any of the
elevators are brought constantly to the
attention of the proper person. A report
on water equipment, plumbing, toilets,
etc., is also made so that a correct con-

««

«.

cuvatIirs

...CT..C..

OUlWtNT

■—

■"• «-l.».~>.

""

•^ .»— f

Ml,

-~ •"*

"

"- •"- -"-

""

— -

—

i~"

ll^^i^^ii^ **" t ^"T^*"**", «,«

1

""

■~*~'

... »-. p« p..

1

_

""~""

— -s,^,^

„.-

E:_--

1

1

Fic. 4, File Cards Showing Work Done on Dynamos, Elevators and the
Electrical Equipment

These cards remain on file for refer- dition of the plant is always at hand,

ence at any time to see how often certain This in a large plant or building is diflfi-

repairs are made or what the cost may cult to obtain without some such sys-

be for any definite time. The time cards tem.

VrCEHLY REPORT ON FIRE APPARATUS DbI

BUTLEW BROTHERS' BUILPIWO.

CrvvHr TanKst LrrH «( >ktr

T^n-tkiM in 'w4f-

Vftlra cMrtr-iOinc tftUm «n Un
R«**ff-v«lri H««M vf watar in ■
•l**ai P«np«i Huw yriMwi

WEEKLY REPORT ON ELEVATOR EQUIPMENT

..Willi wlMMtMT

Dry V«lv*«« Drr v WM*

kam EMlfcrtMii?

rir* Alvmat

W»« VrtiM* AUm Mtif in tnmn pUtw*

** '*!■! ■twTiiii ill mil iiin'

llvAi fl«M tan m ptat* m4 m or4tr tni r*m4r i'w

An fn fiUi>o*fcM ■ •

Figs. .^ and 6 Weekly Rkj'ort Blanks on Fire Apparatus and Elevator Equipment

POWER

November 21, 191 1

The Largest Turbine in the World

On November 3, the largest turbine in
Ihe world was placed in service at the
Waterside No. 1 station of the New York
Edison Company.

The machine is of the Curtis vertical
type, having a rated capacity of 20,000
kilowatts, or about 27,000 horsepower;
sufficient to supply all the current for the
city of Providence or any city of about
250,000 population. Alone it would sup-
ply a chain of cities such as Albany,
Syracuse and Utica.

A striking example of the rapid develop-
ment in prime movers and the concen-
tration of power was afforded when the
new unit, in being thrown onto the line,
took over the load of seven large ver-
tical reciprocating engines, any one of
which occupied nearly as much space as

The prsi of three 20,000-
kilowatt Curtis turbines was
placed in service at the
1 1 'atcrside station of the Neic
York Edison Conipa)iy on
Xovember 3. The machine
is 35 feet high, covers an
area 0/297 square feet and
7c'eis^hs 420 tons.

and furnishing three-phase, 25-cycle cur-
rents at 6600 volts. In order to protect
the windings against the effects of a
short-circuit or a sudden rush of current

Ixjad.
Kilowatts
10,000
15,00(1
20,000

Steam, Pounds

per
Kilowatt-hour

15

14,4

15

Total Steam
per Hour,
Pounds
1.50 000
216,000
300,000

The exhaust steam is handled by a sur-
face condenser placed in the foundation
under the turbine. It is estimated that
about 86,000,000 gallons of condensing
water will be required per day when op-
erating under full load.

A large air duct leading from the
outside of the building to the upper part
of the generator conveys 80,000 cubic
feet of air per minute for cooling the
generator windings.

The illustration shows the turbine
about to he started by George B. Cortel-
\ou. formerly Secretary of the Treasury

20,000-KiLO\\ATT Turbine Being Placed in Service

the new machine. The latter stands 35
feet 7 inches above the base and is
approximately 17 feet in diameter, cover-
ing an area of 297 square feet. The
total weight is 420 tons.

The generator is of the four-pole (;ype,
running at 750 revolutions per minute

in the line, choke coils are inserted in
the leads.

The guaranteed steam consumption of
the turbine when running with steam at
175 pounds gage and 100 degrees super-
heat and a 28' _■ -inch vacuum, is as fol-
lows :

and now president of the Consolidated
Gas Company, of New York.

It is planned to install two more units
similar to the one described, the three
occupying the space formerly taken up
by four 3500-kiIowatt engine-driven
I' nits.

November 21, 1911

POWER

771

Philadelphia's Oldest Steam Engine

In striking contrast to the great 20,000-
kilowatt turbine of the New York Edison
Company, which is described on the op-
posite page and which represents the
latest development in prvre movers, is
an old beam engine which has bec" in
continuous service, pan of the time both
night and day, for the past 64 years.

This engine is doing duty at the plant
of Wetherill & Bros.' white-lead works
at ll^i South Thirtieth street. Phila-
delphia, and, so far as can be ascertained,

^^^^^^1

^

By A. U. Blake

Dcsoiptiofi of asiccnn cii-
giiU'icliichhasbec)iinconfi)i-
iioits service since 1847. //
IS of the single-cylinder slide-
valve type and dccelops 122
horsepower when runn ing on
100 poimds steam pressure.

Fic. I. Elevation of Engine

is the oldest engine in actual operation
in that city. The engine was built in 1847
by J, T, Sutton & Co,

It is of the plain slide-valve tvpe (see
Fig. 2), the valve yoke being worked
off the rocker shaft which, in turn, is
actuated by an eccentric on the main
shaft. The cylinder is 15x48 inches and,
although designed to develop 7.5 horse-
power, it is now carrying a lead of 122
horsepower when running on 100 pounds
steam pressure.

The beam is carried by a central col-
umn 14 feet high, which formerly served
as an open feed-water heater, the ex-
haust steam being led from the cylinder
through the engine frame to the column,
and the feed water flowing by gravity to
a plunger pump worked from the beam.
About two years ago, however, the use
of this heater was discontinued.

The flywheel is about 14 feet in diam-
eter and the connecting rod is attached
to the center crank by a drag pin.

In addition to the machinery driven
from the main shaft a vertical rod ex-
tending upward from the beam operates
12 plunger pumps through a system of
bell cranks.

The chief engineer of the plant is J, .M,
Todd, who takes great pride in this relic,
representing the engine practice 01 over
half a century ago, and who is always
pleased to show it to visitors.

Fic. 2, Showing Cylindkr and Valve Gear

Fic. 3. Crank End of Bnoine. The Small
Engine in Foreground is Another Unit

772

POWER

November 21. 1911

The Power of the Atlantic Fleet

From every standard of comparison,
the most notable fleet ever assembled by
the United States was that reviewed by
President Taft and Secretary of the Navy
Aleyer at New York on November 2. It
involved the greatest number of Ameri-
can vessels ever mobilized, and the great-
est total displacement and the maximum
in fighting effectiveness probably ever
gathered at one point by any nation.

Contrast in Displacement

As indicating something of the in-
creased strength of the Navy, it is in-
teresting to contrast the number of ves-
sels and their total displacement which
took part in other important American
naval reviews. In the international naval
review at New York in March, 1893,
there were 14 naval vessels of all classes
with an aggregate displacement of 39,-
436 tons. President Roosevelt, in Septem-
ber. 190fi, reviewed at Oyster Bay the
Atlantic fleet, then comprising 45 ves-
sels displacing 279,612 tons. During the
Jamestown Exposition there was mo-
bilized at Hampton Roads in June, 1907,
a fleet of 33 vessels, displacing 285,251
tons. When the Atlantic and Pacific fleets
met at San Francisco in May, 1908, they
combined a total of 46 vessels displac-
ing 407,924 tons, and in September,
1909, at the Hudson-Fulton celebration,
43 vessels were assembled with a total
displacement of 316,762 tons.

This latest review at New York in-
cluded 102 vessels of all classes, dis-
placing about 577,285 tons; this does not
include the eight submarines, of which
no figures were available. Concurrently
at Los Angeles a review was taking place
of 24 vessels of 1 16,000 tons displace-
ment, giving a grand total of 126 vessels
displacing 694,000 tons. Perhaps the
most striking evidence of the Navy's
progress is that of all the vessels in the
New York review, the only ones in com-
mission at the time of the Spanish War
were the battleships "Iowa," "Indiana"
and "Massachusetts"; the gunboats
"Castine," "Nashville," "Marietta" and
"Petrel," a few of the small torpedo boats
and some of the fleet auxiliaries.

An Analysis of the Fleet
The following table shows the num-
ber of vessels of each class in the
Atlantic fleet and their total displace-
ment:

C'1..\SS .VNli IiISI'l..\rTOIKNT

Tons

24 ImtdPMliips .•U56,8fi4

U armored cniisers "in. 0(10

2 cniisors O.fl.lo

22 dcstro.vors 1 .".4(i:{

1(> torpedo boats 2,!)!H

Vessels number 102 (uul
cost $123,000,000. The
total boiler capacity is i ,000-
000 horsepower. Propelled
at their full power all of
the vessels would consume
20,000 tons of coal per doy.

8 sul)inarinps

'A tenders to torpedo tleet.

4 p^mlioitts

0 miscellaneous

.S colliers

1 oil tanker

:t tiias

.s.4(!()

4.7:i7

4o.t:!:i

n:!.!is.s

(!.1.-.!)

102 vessels of all classes.

Wide Use of Water-tube Boilers

Exclusive of the submarines, these
vessels represent a total horsepower of
946,811. for the supplying of which there
are 567 boilers aggregating 46,360 square
feet of grate surface and 2,062,000
square feet of heating surface. All of
the battleships, cruisers and torpedo
boats except the battleship "Iowa" have
water-tube boilers. This is a reversal
of conditions during the Spanish-Ameri-
can War. when outside of the torpedo
boats there were only four warships
equipped with water-tube boilers.

Oil as Fuel

Seventeen of the destroyers burn oil
as fuel and the four latest battleships,
the "Delaware," "North Dakota," "Utah"
and "Florida," burn oil in conjunction
with coal. The fleet has a fuel-oil tank
ship to carry the reserve fuel for these
vessels, serving the corresponding func-
tion of the eight colliers carrying the
coal supplies for the other vessels.

Coal Capacity

The aggregate coal-bunker capacity of
the fleet is 81,450 tons. Adding to this
the coal-cargo capacity of the colliers,
58,813 tons, the fleet can sail away with
a total of 140,263 tons of coal. Propelled
simultaneously at their full power, all of
the vessels would consume coal at the
rate of 20,000 tons a day.

.Money Invested

The Government has invested in this
fleet S123,397.400. exclusive of the cost
of supplies of all kinds and the salaries
of the officers and crew.

With its full complement the fleet would
carry 27,344 men and 1650 officers, a
total of 29,004.

Over Five Miles Long

The average speed of the vessels is
21.6 knots. The fastest vessel is the
destroyer "Paulding," which is capable
of making 32.8 knots. Placed end to
end, touching, the vessels of the fleet
would extend 29,942 feet, or over 5;.;
miles. Placed in single file 300 yards
apart, the fleet would form a line nearly
23 miles long, and at an average speed

of 10 knots an hour it would take about
two hours to pass a given point.

Pumping Equipment

It is self-evident what such a fleet as
this means to the ship-building and
ordnance-manufacturing industries, but
there are also less intimately associated
industries that played an important part
in the fleet's equipment. For example,
the Blake & Knowles Steam Pump
Works have installed pumping equipment
on 65 of these vessels. This is a large
percentage considering that nine of the
remainder carry no steam pumps, includ-
ing the submarines and one sailing ves-
sel, and that eight of the others, princi-
pally colliers, were built abroad. The
number of pumps this company has in-
stalled on the fleet exceeds 1000, and
their cost represents nearly $1,250,000.

Pennsyl\;inia Produces One
Fifth of ^^'orld's Coal

In the combined production of anthra-
cite and bituminous coal Pennsylvania
outranks any of the coal-producing
countries of the world except Great
Britain and Germany, and in 1910, re-
ports the United States Geological Sur-
vey, it came within 10,000,000 shon tons,
or less than 5 per cent., of the output of
Germany. Pennsylvania's production in
1910 was more than four times that of
Austria-Hungary in 1909, more than five
times that of France in 1910, and nearly
20 per cent, of the total world produc-
tion. The industry, particularly in the
bituminous districts, has kept pace with
the manufacturing industries and has in-
creased in considerably larger ratio than
the population of the State and of the
United States as a whole.

From 1814 to the close of 1910 the
total production of anthracite had
amounted to 2,180,323,469 short tons.

Elektrotcchnika, of Budapest. Hun-
gary, states that a power plant will short-
ly be erected on the River Cetina near
.^Imissa in Dalmatia' for the "Societa
Anonima per la Utilizzazione delle Force
Idrauliche delle Dalmazia. Triest, Austria.
It is estimated that 200,000 horsepower
is available at the waterfall, but of this
only 40.000 horsepower will be at first
utilized. The central station which is to
be installed by Ganz & Co., Budapest,
Hungary, will contain two 20,000-hor6e-
power units and four 18,000-kilovolt-am-
pere three-phase transformers. The gen-
erators will be the largest in Europe,
and the transformers the largest in the
world. The distance from the falls to the
plant, which is situated on the Mediter-
ranean, is 16 miles. At the power house
55,000 volts will be available.

November 21, 1911

POWER

773

The Isochronous Governor

The duty of a steam-engine governor is,
first, to so proportion the expenditure of
steam per stroke as to maintain the nor-
mal speed constant, whatever the useful
load, so long as it remains between zero
and the maximum assigned; second,
to restore the speed to its normal
value when variations have been pro-
duced by changes in the load. To effect
this the governor is composed of two
parts, one a centrifugal apparatus, sen-
sitive to variations in speed and ordi-
narily called a tachometer; the other, an
organ which, under the control of the
tachometer, proportions the admission of
steam per stroke, either by throttling or
by varying the degree of expansion. For
simplicity let it be supposed that this
organ is a throttle valve. When the en-
gine runs with a given load, at the nor-
mal speed, the movable sleeve of the
governor must stand at the hight h ( Fig.
1 ), corresponding to the useful load pres-
ent, and when this load changes in such a
way as to require another hight h'. in
order to maintain the speed at the nor-
mal, it is necessary that the sleeve should
change its position to the h' plane.

The ordinary theory wrongfully as-
sumes that what is commonly called the
isochronous governor will realize this
ideal. It says that for the sleeve to rest at
the hight h when the engine is running at
the normal speed, it is necessary that for
all the positions between H . and H, the
centrifugal force of the balls shall bal-
ance the weight of the balls and the
sleeve, friction being neglected. It es-

By Prof. \'. Dwelshauvers-Dery

Hi"

Ui

Velocities ""

Fig. t.

tablishes, therefore, a relation between
the hight h and these three forces in
such a manner that, h being given, one
can deduce the velocity of equilibrium u.
Let it be supposed that for a given
governor the values of the speed of
equilibrium u for different hights h have
been so calculated as to pennit the plot-
ting of the diagram. Fig. I. as follows:
On the vertical H . H., starting from W ,
are laid out the ordinates as /: — H W.
From WW as a base lay out horizontally
the distances, as W u, proportional to the
velocities u as calculated. The location
in this way of the points u on the
curve will serve — after the ordinary

The covnnoii theory of
the pendulum governor as-
sumes that for eaeh partieu-
!(ir plane that the governor
assumes the weight of the
balls is just balanced by
their centrifugal force.

The author points out
that, owing to friction and
to the resistance of the mech-
anism to which the gover-
nor is conn^'cted, there are
two velocities of equiUtniii in
lor each position, and that
any theory which docs not
take both into account must
he in error.

theory — to describe the qualities of a
governor. For example: If the diagram
described by these points is a straight
vertical line, as u, in Fig. 1, the governor
is assumed to be isochronous and per-
fect, and it is this quality which so many
inventors have sought, happily in vain.
But one governor is known which is real-
ly isochronous — that of Rankine — and if
it were applied to an engine it would be

v; u, w,

u. vv;

found, instead of regulating it, to put the
jpeed out of order.

The ordinary theory takes into account
but one single velocity of equilibrium ii
for the hight h. and assumes that the
sleeve cannot maintain itself at that hight
imless the engine runs at that velocity ii.
It assumes that if the actual velocity
becomes ever so little more or less than
II the sleeve must rise or fall. It takes
account of the tachometer only, without
considering the resistance R that the
throttle valve offers to movement or the
resistance due to friction. There are,
therefore, in reality for each hight W
two velocities of equilibrium, one w for

the ascension of the sleeve and the
other V for the descent, and the velocity
II, which is greater than v and less than
«', is nothing of a velocity of equilibrium
for the governor.

In Fig. 2, indeed, suppose the sleeve to
be at the hight h and the engine running
at the normal speed u — H u. Suppose
that suddenly the load is diminished and
that in order to proportion the admission
of steam per stroke to the normal velocity
u, the sleeve must be raised to the hight
h'. At first the actual speed of the engine
will increase, but without raising the
sleeve, because of the friction and the
resistance R of the throttle valve, and it
is necessary that the speed shall be in-
creased and take a certain value w, in
order that the sleeve may commence to
rise. This speed w is, therefore, the
velocity of equilibrium for ascension for
the hight It. It is represented in Fig. 2
by the horizontal length H w. Operating
in the same way for various hights h.
the diagram H',, W, of the velocities of
equilibrium for the ascension may he
plotted.

If, on the contrary, the sleeve being
at the hight h, the actual velocity of the
engine is diminished by a sudden in-
crease of the load, the sleeve will not
immediately descend. It is necessary
that the centrifugal force shall be
diminished until the weights are suffi-
ciently in excess to put the throttle valve
into motion. Then the speed, which takes
the value i' — W r of the diagram. Fig.
2, is that which establishes the equi-

C

B

V,

■*',

«>

i

«

)k

%

I'H

-j—r

h h

. ..'V- ^v

w

H,

i i

V.

1

W

I

> e

Veloci+ies
Fic. 3.

librium of descent between the centrifu-
gal force, the weight and the inevitable
icsistance. This value v being known
for different hights h. one can plot the
diagram V V, of Fig. 2.

Therefore, there arc for each position
h of the sleeve two real speeds of equi-
librium, one w for the upward move-
ment, greater than ii. and the other r for
the downward movement, smaller than u.
and it can readily be seen that the sleeve
will remain wherever it is. whatever may
be the load upon the engine, so long as
the speed rests between u' and r.

In consequence, the difference w — v
gives the measure of the sensibility of

774

POWER

November 21, 1911

(he governor. The ordinary theory as-
sumes that this sensibility is infinite,
which is absurd. It wrongfully assumes
also that the qualities of a governor, as
revealed by the diagram of its tachometer,
are independent of the throttle valve.

It is desirable in practice that there
should be but a single velocity, that of
the normal operation, at which the
sleeve could remain at the hight
at which it finds itself wherever it
may be. In this condition a governor
could be said to be perfect. Its diagram
is given in V.. U,, W, U.. of Fig. 2. The
diagram of a governor rigorously
isochronous would be that represented in
Fig. 3 by H' = constant and v = constant.
The two diagrams, that of i' and of w, are
straight-line verticals, as well as that of
II, but it should not be supposed that be-
cause a governor has been calculated in
such a way that the velocity u is con-
stant it will for that reason be isochronous
in reality. Aside from the governor of
Rankine, among the immense variety of
governors invented to satisfy the condi-
tion u = constant, no other governor is
known which, with a constant resistance
k of the throttle valve, would be really
isochronous. All have diagrams proving

Velocities
Fic. 4.

that they operate at times in an inverse
direction. The most reputable have a
diagram such as that in Fig. 4, showing
that the governor operates very well
during the descent but in the inverse di-
rection during the ascent, since the veloc-
ity of equilibrium for the ascension W„
in the lower position is greater than the
velocity of equilibrium W, in the higher.
But there is more. A perfectly isoch-
ronous governor. Fig. 3, would derange
the engine instead of regulating it. Sup-
pose the sleeve at the hight h ( Fig. 3) and
the load on the engine corresponding to
the velocity u. Suddenly a part of the load
is removed, and in order that the speed
shall remain equal to u the sleeve must
be moved to the hight li'. The actual
velocity will increase, and the sleeve will
rise when that velocity has become equal
to II' ; but as soon as that value is at-
tained, the sleeve will rise with greater
and greater velocity and nothing will
stop it until it is arrested by the upper
collar at H,, and there it will prevent the
admission of any steam at all if the gov-
ernor is correctly set. But then the
actual speed will diminish as the engine
is no longer supplied with steam, and

will finish by becoming equal to v;
at this moment the sleeve will fall and
keep on falling until it is arrested by
the lower collar at H., opening the throttle
valve completely. Then the velocity will
increase and soon become equal to W„,
and the sleeve will precipitate itself again
toward the upper collar. There will thus
be established periods of greater and
less velocity, with a complete unsettle-
ment of the regulation of the engine, and
it would be impossible to foresee many
circumstances which might influence
these events in such a manner as to in-
terfere with and ameliorate the action
which we have described.

To recapitulate, the ordinary theory of
governors is false, because it does not
take into account the resistance of the
throttle valve and of the friction oppos-
ing the movement of the governor sleeve;
that it deals with but one velocity of
fictitious and not true equilibrium,
instead of the two velocities of actual
equilibrium; that it is incapable of de-
fining the sensibility of a governor; that
it does not offer a means of satisfying
the exigencies of practice. The real,
practical governor has for a diagram that
indicated in Fig. 2 by V.. U,. W, U... Or-
dinarily, in practice the resistance of the
throttle valve is variable, and it is by
guessing that the engineer regulates the
governor, without being able to explain
to himself precisely why. so as to realize
somewhere near this diagram.

The real theory of the governor was
given by Monsieur Ch. Beer, engineer at
Liege, Belgium (1877), and developed by
the writer.

Sampling Coal

By Ch.arles M. Rogers

Many methods have been proposed
and considerable difficulty has been en-
countered in arriving at the most ac-
curate and easiest way for sampling coal
and preparing it for analysis. To the
writer's knowledge, the sampling scheme
here described is not practised in many
places, although it proves to be inex-
pensive and satisfactory, especially where
the coal is received in cars and has to
be sampled and analyzed regularly each
day. Of course, this method of car
sampling could not be used for any
other than slack coal, or coal sufficiently
small to be admitted into a 1 ' >- or 2-inch
pipe.

A 2-inch iron pipe 5 feet long is closed
at one end and the open end is cham-
fered or sharpened on the outer edge;
this is driven vertically to, or nearly to,
the bottom of each car at six different
places. When drawn up the pipe is full
of coal which represents a sample from
top to bottom of the car, and it is easily
made to fall out into a bucket by a few
slight taps with a hammer.

The samples thus taken from all the

cars are carried to a convenient place
in the boiler room and thoroughly mixed
in a container which is of sufficient size
so that when it contains the samples
from all the cars it is about one-half
full. It is cylindrical in shape, is made
of 's-inch sheet iron, and is provided
with a bearing on each side for mounting
purposes, and a top which is easily held
fast by clamp screws. The spindle which
passes through the center and upon
which the mixer revolves is fitted with
arms which project to the sides so as to
insure a thorough mixture of the coal.

After the coal has been thoroughly
mixed, which is effected by about twenty-
five revolutions of the spindle, the lid i^
removed and it is dumped upon the plat-
form below. The laboratory sample of
approximately 4 quarts is then taken b;-
quartering down in the usual mannei.
The remainder is shoveled into the stoker
magazine or into the bucket conveyer
which passes within 5 feet of the mixer.

In the laboratory- the entire sample
is run through a crusher which delivers
it at '4 -inch mesh or smaller. This is
then quartered down twice, and the re-
maining sample, about one quart, is run
through a coffee grinder. About 200
grams are then used for the moisture
determination and a portion of the re-
mainder is properly labeled and put
away for further reference.

After the moisture is expelled and its
percentage detemiined. the coal is run
through a pulverizer, which, at one grind-
ing, delivers it at 100 mesh. About 25
grams of this final sample is then put
in a desiccator Tor determinations of
heat value, ash, volatile combustible mat-
ter, fixed carbo. ^''nd sulphur.

The heat value is determined by an
Atwater oxygen-bomb calorimeter, and
the sulphur by the Eschka-Fresenius
method. The ash, volatile matter and
fixed-carbon determinations closely re-
semble those recommended by the spe-
cial committee appointed by the Ameri-
can Chemical Society.

There should be no question as to the
accuracy of this method in furnishing
a representative sample. No matter how
large or how small a car is as compared
with the others, the same proportions ex-
ist in the final sample that exist in the
cars.

The time required outside of the labora-
tory work is less than one hour. In
the laboratory the coal can be reduced
from its original size to 100 mesh in
about 15 minutes, excluding the one
hour which is required for the moisture
determination before being pulverized.
The crusher, grinder and pulverizer are
driven by a small motor.

The chief engineer of a British en-
gine, boiler and electrical insurance com-
pany is reported by Engineering as say-
ing that out of every 45 engines insured.
20 are driven bv gas.

November 21. 1911

POWER

epartmen

The Bell Single Phase Mottir

With a view to meeting the require-
ments of heavy starting torque and mod-
erate initial-current rush, where only
alternating-current supply is available.
the Bell Electric Company, Garwood,
N. J., has brought out a line of single-
phase motors the construction of which
is indicated in the accompanying illus-
trations.

The motor starts on the repulsion prin-
ciple and upon reaching a speed slightly
below normal is changed, by the action
of a centrifugal governor, to the equiva-

as Fig. 3 indicates. The winding is of
the distributed type connected to a com-
mutator in the same manner as that of
a direct-current machine.

Fic. 1. Bell Sinxll-phash Motor

lent of a squirrel-cage induction motor.
This method is not new. of course, and
the electrical principles involved are
therefore not discussed in this article.

Fig. 1 is a perspective view of the com-
plete machine and Fig. 2 is an end view
of the stalor core and housing, which are

Stator Fra.me

At the speed where the machine is
changed from a repulsion to an ordinary
induction motor, the centrifugal gover-
nor overcomes a restraining spring and
forces a short-circuiting ring against the
end of the commutator. The construc-
tion of the short-circuiting ring is show-n

nng

governor and short-circuiting
position on the shaft.

Fig. 6 is a chart showing the perform-
ance of the 5-horsepower machine illus-
trated in Fig. 1. The free (synchronous!
speed is 1800 revolutions per minute and
the frequency 60 cycles. This chart

Fic. 3. Ar.mature of Bell Single-phase

Motor

does not show the starting current taken.
The builder states that it is less than
the current per phase taken by standard
pohphase motors of equal power.

Power and Current in Three
Phase Circuits

By Cecil P. Poole

The current per wire of a balanced
three-phase circuit depends upon the
power transmitted, the power factor of
the circuit and the voltage. The power
transmitted is determined, of course, by
the mechanical power delivered by the
motor or motors In the circuit and by
the efficiency of conversion from elec-
trical to mechanical power. With suit-
able instruments all of these various fac-
tors except the efficiency of conversion
can be ascertained at a glance and the
efficiency can be determined without very
much trouble. The relation between them.

CIRCUITING Mechanism Disassembled

Assembled

exactly like those of the ordinary induc-
tion motor. The coil slots of the stator
are partly closed and the winding is of
the usual single-phase type. The rotor
or arinature is very similar in appear-
ance to that of a direct-current motor.

in Fig. 4, which also shows the commu-
tator and governor. The ring is slotted
radially around its Internal circumfer-
ence, in order to provide good electrical
contact between it and each commutator
bar independently. Fig. .S shows the

however, even w^hcn all of the requisite
instruments are at hand, cannot be de-
termined without more or less tedious
figurine, and the tables will be found
of considerable convenience in reducing
the amount of such figuring.

776

POWER

November 21, 1911

Table 1 shows the electrical power in
kilowatts taken from the line for each
horsepower delivered at the pulley or
shaft of a motor, over the entire prac-

be used regardless of voltages, power
factors or other considerations, for the
reason that it deals only with power
and therefore involves merely the reduc-

the various efficiencies. Electrical power,
which is almost invariably measured in

tical range of efficiencies. This table may tion of electrical to mechanical power at

' ' ' ■ 1 1

\ ' 1 ! ; 1 ! <<

A'-'

'■ 1 r

L^_1_L-

1 1140

H.p.m

1

i

tWcienc

y

1

1

-— '-^

■ — '

4-

1 ' i

\yf^

oy

f'

---

■"^i

1

1

/

'

<<>'>

:

7000

_L_' /

ji'

</

''

\

/

9.4^

1

^

6000

i ,

/

A 1

^

y^

7l^

>--

\

500O

'/

7; 1

1

pr 'II

/ /

^

4000 40

L A-rtS^

^

J

^

^

t

,^

j

J

j

i

2000 20 8.
E

^

^

-

r^

.^

— -i — 1 —

r

1000 10

i;,>--7

^'"" \rv

1

! . ' :

\ \

1

i i 1

!

n n

Ho'iepo-~er "»""

Fic. 6. Test Curves of 5-horsepo>x'er, 60-cycle Bell Motor, at 220 Volts

Horsepower

Kiiowalts

Efficiency

Kilowatt

Horsepower

Efficiency

60

0.805

1.243

60

61 -

0.818

1.222

61

62

0.831

1.203

62

63

0.845

1.184

63

64

0.858

1.165

64

65

0.872

1.147

65

66

0.885

1.130

66

67

0.898

1.113

67

68

0.912

1.097

68

6!)

0 . 925

1.081

69

70

0.939

1.065

70

71

0.952

1.050

71

72

0.966

1.036

72

73

0.979

1.021

73

74

0.992

1.008

74

75

1.006

0.994

75

76

1.019

0.981

76

77

1 . 033

0.968

77

78

1.046

0.956

78

79

1 . 059

0.944

79

SO

1.073

0.932

80

81

1.086

0.921

81

82

1.100

0.910

82

83

1.113

0.898

83

84

1. 126

0.888

84

85

1.140

0.877

85

86

1.153

0.867

86

87

1.167

0.857

87

88

1.180

0.848

88

89

1.193

0.838

89

90

1.207

0.829

90

91

1.220

0.820

91

92

1 . 234

0.811

92

93

1.247

0.802

93

94

1.281

0 793

94

TABLE 2. AMPERES PER KILOWATT IN EACH LEG OF A BALANCED THREE-PHASE LINE

Pow-

Volts betweex

Any T

wo WmK.s

Fac-

tor

100

110

125

200

220

250

440

500

550

1100

1150

2200

2300

6600

13,200

50

11.55

10. 50

9.24

4.62

2.62

2.31

2.10

1.050

1.004

0.525

0.502

0.175

0.0875

.51

11.32

10.29

9.06

5.66

5.15

4.53

2.57

2.26

2.06

1.029

0.985

0.515

0.492

0.172

0.086

52

11.10

10.09

8.88

5. 55

5.05

4.44

2.52

2.22

2.02

1.009

0.966

0.505

0.483.

0.168

0.084

53

10.89

9.90

8.72

5.44

4.95

4.36

2.47

2.18

1.98

0.990

0.947

0 . 495

0.474

0.165

0.0825

54

10.69

9.72

8 . 55

5.34

4 86

4.28

2.43

2.14

1.94

0.972

0.930

0,486

0.465

0.162

0.081

55

10.. 50

9.54

8.40

5 -'5

4.77

4.20

2.38

2.10

1.91

0.954

0.913

0.477

0.456

0.159

0.0795

56

10.31

9.37

S.25

5.15

4.69

4.12

2.34

2.06

1.87

0.937

0 . 897

0.469

0.448

0.1.56

0.078

57

10.13

9.21

8. 10

5.06

4.60

4.05

2.30

2.03

1.84

0.921

0..SS1

0.460

0.440

0.1.53

0.0765

58

9.96

9.05

7.96

4.98

4. 53

3.98

2.26

1.99

1.81

0.905

0.866

0.453

0.433

0.151

0.0755

59

9.79

8.90

7 . S3

4. 89

4.45

3.92

1.96

1.78

0.890

0.851

0.445

0.425

0.14S

0.074

60

9.62

8.75

7.70

4.81

4.37

3.85

2. IS

1.92

1.75

0.875

0.837

0.437

0.418

0.146

0.073

61

9.46

8.61

7 .57

4.73

4. 30

3.79

2.15

1.89

1.72

0.861

0 . 823

0.430

0.411

0.143

0.0715

9.31

8.47

7 . 45

4.65

4.23

3.72

2.11

1.S6

1.69

0.847

0.810

0.423

0.405

0.141

0.0705

63

9.17

8.33

7.33

4.58

4.16

3.67

■>.os

1.83

1 67

0.833

0.797

0.416

0.398

0.139

0.0695

8.20

7 22

4 . 51

4 10

3.61

2.05

ISO

1.64

0.820

0.784

0.410

0.392

0.137

0.0685

65

S S.S

S.07

7 10

4.44

4.03

3.. 55

2.02

1 7S

1.61

0.807

0.772

0.403

0.386

0.134

0.0670

66

.S 75

7.95

7.00

4.37

3.97

3.50

1 .99

1 75

1.59

0.795

0.761

0.397

0.380

0.132

0.066

67

.S.62

7.83

6.89

4.31

3.91

3.45

1.96

1 .72

1 . 57

0.783

0.749

0.391

0.374

0.130

0.065

68

S.40

7.72

6.79

4.24

.3.86

3.40

1.93

1.70

1 . 54

0.772

0.738

0.386

0.369

0.129

0.0645

69

8.37

7.61

6 69

4.18

3.80

3.34

1.90

1.67

1.52

0.761

0.72S

0.380

0.364

0.127

0.0635

70

8 . 25

7 50

6.60

4.13

3.75

3.36

1.87

1.65

1.50

0.750

0.717

0..375

0.359

0, 125

0 0625

S. 13

7.39

6.. 50

4.06

3.69

3.25

1 . 85

1.63

1.4S

0.739

0.707

0.369

0.354

0.123

0.0615

72

S.02

7.29

6.41

4.01

3.64

3.20

1.83

1.60

1.46

0.729

0 . 697

0..J64

0 . .349

0.121

0.0605

7.91

7.19

6.33

3.95

3.59

3.16

1.80

1..58

1.44

0.719

0 . 6S8

0.359

0.344

0.120

0.0600

74

7. SO

7.09

6.24

3.90

3.54

3.12

1.77

1 56

1 42

0.709

0.678

0 . 354

0.339

O.lis

0,059

75

7.70

7.00

6.16

3.85

3.50

3.08

1.75

1..54

1.40

0.700

0,669

0 . 350

0.334

0.117

0 , 0585

6.91

6.08

3.80

3.45

3.04

1.73

1.52

1.38

0.691

0,661

0.345

0.330

0.115

0.0575

77

7.50

6.82

6.00

3.75

3.41

3.00

1.70

1.50

1.36

0.682

0.652

0 . 341

0.326

0.114

0.057

78

7 . 40

6.73

5.92

3.70

3.36

2.96

1.68

1.48

1.35

0.673

0.644

0.336

0.322

0.112

0.056

79

7 31

6.64

5 85

3.65

3.32

2.92

1.66

1.46

1.33

0 664

0.636

0.332

0.318

0.111

0.0555

80

7 '2

6.56

5 77

3.61

3.28

2.88

1.64

1.44

1.31

0.656

0.628

0.328

0.314

0.109

0.0545

81

7.13

6.48

5.70

3.. 56

3.24

2.85

1.62

1.43

1.30

0.648

0.620

0.324

0.310

0.108

0.054

6.40

5.63

3.52

3.20

2.82

1.6

1.41

l.-'S

0 . 640

0,612

0.320

0.306

0.107

0.0.535

. S3

6.96

6.32

5.56

3.48

3.16

2.7S

1.58

1.39

1.26

0.632

0,605

0.316

0.302

0.105

0.0525

5.50

3.43

3.12

2.75

1.56

1.37

1 , 25

0.625

0 , 59S

0 312

0.299

0.104

0.0.52

85

fi.79

6.17

5.43

3.39

3.09

2.72

1 .54

1.36

1 . 23

0.617

0.591

0.309

0.295

0.103

0.0515

86

6.71

6.10

5. 37

3.35

3.05

2.68

1.52

1.34

1.22

0.610

0.584

0.305

0 292

0.102

0.051

6.03

5.31

3.32

3.01

2.66

1.51

1.33

1.21

0.603

0.577

0.301

0.288

0.100

0.05

88

6.. 56

5.96

5.25

3.28

2.98

2.62

1.49

1.31

1.19

0.596

0.570

0.298

0.285

0.099

0.O495

5.19

3.24

2.95

2.59

1.47

1.30

1.18

0.590

0.564

0 , 295

0.282

0.098

0.049

90

6,41

5. S3

5.13

3.20

2.91

2.56

1.46

1 '8

1 .17

0 . 5S3

0.558

0,291

0.279

0,097

0.04S5

6.34

.5.7/

5.08

3.17

2.88

2.54

1.44

1 . 27

1 . 15

0.577

0.552

0.2SS

0.276

0,096

0.048

92

6.28

5.70

5.02

3 14

2.85

2.51

1.42

1.26

1 14

0 , .570

0 546

0.2S5

0.273

0,095

0,0475

93

6.21

5.64

4.97

- 3 . 10

2.82

2.48

1.41

1,24

1,13

0,564

0.540

0.282

0.270

0.094

0,047

94

6.14

5.58

4.91

3.07

2.79

2.46

1.39

1 23

1 12

0,5.58

0 . 534

0.279

0.267

0.093

0,0465

95

6. OS

5 . 52

4.86

3.04

2.76

2.43

1.38

1 .22

1 10

0.552

0.528

0.276

0.264

0.092

0.046

4.81

3.00

2.73

2.40

1.37

1.20

1.09

0.547

0.523

0.273

0.261

0.091

0.0455

5.95

5.41

4.76

2.97

2 70

2.3S

1.35

1.19

1.08

0.541

0.518

0.270

0.259

0.090

0.045

2.94

? fiv

•1 35

1.34

1.18

1.07

0.536

0.512

0.268

0.256

0.089

0.0445

5.83

5.30

4.66

2.91

-• 33

1.32

1.17

1.06

0.»30

0.507

0.265

0.254

0.088

0.044

November 21. 1911

POWER

kilowatts, is equivalent to mechanical
horsepower multiplied by 0.746. because
7-46 watts are the practical equivalent of
one horsepower. But for the losses in
the motor this simple multiplication
would be all that is necessary to trans-
late mechanical into electrical units. Tak-
ing efficiency into consideration, the pro-
duct of 0.746 and the mechanical horse-
power must be divided by the efficiency,
written in decimal form, to find the actual
kilowatts of intake. Thus, multiply Ihc
horsepower by 0.746 and divide the re-
sult by the efficiency in hundredths* For
example, if the mechanical horsepower
is 50 and the efficiency 90 per cent.,
0.746 X

will IclNC

kilowatts.

The two sections of Table 1 were cal-
culated by means of the foregoing for-
mula and its transposition. The object
in arranging the table in this way is to
facilitate working in either direction,
which will be made clearer later on.

Table 2 shows the amperes in each
leg of a balanced three-phase circuit for
each kilowatt of actual power transmitted
at any of the various standard voltages
and at different power factors from 50
per cent. up. For e.\ample, at 220 volts,
■ with a power factor of 80 per cent., the
current in each leg of the circuit will
be 3.28 amperes for each kilowatt of
power transmitted. This is found by fol-
lowing down the power- factor column to
the number 80 and then taking the num-
ber in the column under 220 volts which
is on the same line with it. Again, sup-
pose the power factor is 86 per cent,
and the voltage 250; following down the
power-factor column until the number 86
is reached, trace along that line into the
table until the 250-volt column is reached;
in that column is the number 2.68, which
is the number of amperes per wire for
each kilowatt of power.

The following examples will illustrate
the use of the two tables in combination.
Suppose a 20-horsepower 2.SO-voIt motor
is to be installed and the manufacturers
put its efficiency at 88 per cent, and its
power factor at 85 per cent. It is de-
sirable to know how much current per
leg the motor will require in order to
determine the size of wire to be in-
stalled. Referring to Table 1 and fol-
lowing down the efficiency column to the
figure 88, on that line in the kilowatts
column the number 0.848 is found; this
is the fraction of a kilowatt per horse-
power required by the motor. Multiply-
ing this by 20 gives 16.96. or practically
17. kilowatts for the electrical intake of
the motor. Now referring to Table 2,
- tailing at 85 per cent, power factor in

•In Mic fiircn of nil i(|iinllon :
n.~4»ly'iD.

nnd Ihp Iraniipoolrinn In
K,r vr/r.
0.740

= lew.

-h.p.

the left-hand column and following along
that line to the 250-volt column, the
number 2.72 is found. This is the cur-
rent per kilowatt, and multiplying it by
the 17 kilowatts taken from Table 1
gives 46.24 amperes per wire as the full-
load motor current. Adding 25 per cent,
margin for starting current, as required
by the insurance rules, the capacity of
each wire must be not less than 58 am-
peres.

The tables are also convenient in de-
termining the efficiency of a motor with-
out going through the tedious arithmetical
process which is necessarj' no matter
how many instruments may be available.
For example, suppose a 550-volt three-
phase motor is being tested with a prony
brake and when loaded to 30 horsepower
takes 30' j amperes in each leg of the
circuit with the power-factor meter show-
ing 87 per cent.; what is the efficiency
of the motor? Referring to Table 2, it
will be found by tracing from 87 per
cent, power factor in the left-hand col-
umn over to the 550-volt column that
1.21 amperes represent one kilowatt;
therefore, 30' , amperes represent 30.5
:- 1.21 — 25.2 kilowatts. Dividing this
ty the brake horsepower gives 25.2 -^ 30
= 0.84 as the fraction of a kilowatt
which the motor is taking from the line
per horsepower delivered. Tracing down
the third column of Table 1 until the
nearest number to this (0.8381 is reached,
the number 89 will be found opposite it
in the efficiency column; the efficiency of
the motor, therefore, is practically 89
per cent.

Suppose that a motor was driving a
load which could not be measured di-
rectly and it was desired to get an idea
of what the load was and what power
factor the motor was showing, no power-
factor meter being available. With a
wattmeter, ammeter, voltmeter and the
manufacturer's performance chart, which
may be had with any motor, the behavior
of the machine can be analyzed with
very little trouble. The voltage should
be normal in order to avoid troublesome
arithmetic and more troublesome correc-
tions. Suppose the motor to be a 15-
horsepower 220-volt machine, the elec-
trical intake 7 kilowatts and the current
per leg 23 amperes. Dividing 23 by 7
gives 3.29 as the current per kilowatt.
Following down the 220-volt column in
Table 2. the nearest number to 3.29 is
3.28, and this is in line with 80 per cent,
power factor in the left-hand column.

Now referring to the manufacturers'
chart, suppose that if shows that at the
load where the motor power factor is 80
per cent, its efficiency is 84 per cent.
Table 2 shows that at 84 per cent, effi-
ciency each kilowatt of intake is equiva-
lent to 1.126 horsepower at the pulley.
The intake Is 7 kilowatts; the power be-
ing delivered, therefore, is 7 ■' 1.126 -
7.882. or practically 7.9, horsepower^ Al-
though this method will not always give

absolutely correct results, it is close
enough for all practical purposes.

The right-hand portion of Table 2 is
useful for getting an idea of the power
factor of a line when no meter is avail-
able for that purpose. It is only neces-
sary to divide the current per leg by the
kilowatts and to find the result in the
table. For example, suppose the ammeter
in one leg of a 2300-volt circuit showed
200 amperes, and the indicating power
meter 625 kilowatts. The current per
kilowatt would be 200 -^ 625 = 0.32 am-
pere. The nearest numbers to this in the
2300-volt column of Table 2 are 0.318
and 0.322, which correspond to 79 and
78 per cent, power factors; as the exact
current per kilowatt is half way between
0.318 and 0.322, the power factor is
half way between 79 and 78, or 78 'j per
cent. Fractions of I per cent., how-
ever, are of no importance so far as the
power factor or its influence on the cir-
cuit is concerned.

LETTERS

Mr. Hawkins' Conipre.s-sor
Motor

Some time ago I had almost exactly
the same trouble with a motor operating
an ice machine as- that described by J. C.
Hawkins in the October 31 issue of
Pow KR. My motor was a 5-horsepower
shunt-wound 220-volt machine and had
had one new commutator in three years
and needed another. Stop its sparking
I could not, although I tried everything
1 knew and some things I did not. The
motor did not seem to be overloaded, yet
it sparked so badly and ran so hot that
I had to keep a little desk fan blowing
on it all the time. Finally, I built up
the foundation so as to put the motor
well up in the air (it is located in a
dark, damp basement) and on top of
the concrete I bolted two 6x6-inch pine
timbers and to these bolted a 10-horse-
power motor — and my troubles were
over. I have to wipe the commutator
of this motor occasionally and once in
a great while lightly sandpaper it.

A friend of mine had the same trouble.
He raised his motor farther up away
from the ground and used a soft graphite
brush; he thinks the soft brush did the
business. Mr. Hawkins might try the
soft brush; a compound-wound motor
would not help him any. I do not think
the actTon of the compressor has any-
thing to do with the sparking. 1 have
a good many motors on different kinds
of service and the one I have just men-
tioned was the only one to give me
trouble. I think it was the location and
a little loo heavy a load. If the bruslics
chatter, the mica is high and Mr. Haw-
kins needs to u*c a commutator stone.
C. A. Scott.

Wales. Wis.

778

POWER

November 21, 1911

A g>

Test of an Atlas Diesel Oil
Engine

The Atlas Engine Works, of Indian-
apolis, some time ago took up the manu-
facture of Diesel-type oil engines and
during the summer just closed a 300-
horsepower unit was put through a com-
prehensive test under the supervision of
C. E. Sargent, consulting engineer. Fol-
iowing is an abstract of Mr. Sargent's
official report:

The object of the test was to deter-
mine the quantity of fuel used per unit

Everything'
fvorth while in the gas
engine and producer
industry will he treated
here in a way that can
he of use to practi-
cal men

glass column. The hight of the oil was
noted at the beginning of each test and
the quantity of oil pumped into the tank

Seven runs of from 1 to 4 hours each
were made, varying the load from the
smallest that could be run in parallel
with the steam-driven generator to the
heaviest load the generator could carry
without overheating.

The variation in speed between the
lightest load and 25 per cent, overload
did not exceed 2 per cent., and the en-
gine showed no tendency to race with
light loads or overreach with a changt
of loads.

Table I is the log of one of the full-

T.\Br,E

1. I.n

; OF ONE OY

PHR IT

.1, r.O.\l) RIN'.-

i T.

^

o S 2

s

=

oS

:i

J§

g

SIS

s

y—

.1

(5

III

|3

3

Discharge '

5 M
o ^

It

li

111

50-

2
3

tz

No. 1

No. 2

Cyl.

^5

1.00

60

.S,.>80

173

93

186

180

340

225

90,364

47.269

18U

1:30

72

3,738

5,1.58

172

62

94

175

178

1,200

940

235

90,462

98

47,282

13

18.5

2:00

72

S,897

5,159

1 1 2

65

94

177

204

1 ,600

900

235

90.567

105

47,297

15

190

2:30

73

4,048

5,151

172

65

95

192

194

1,200

900

230

90,672

105

47.31'

\b

200

3:00

73

9,210

5,162

172

63

96

195

ISS

1,600

880

230

90,775

103

47.327

15

205

.■i:30

73

4,367

5,l.->7

172

62

96

192

192

1,200

875

230

90,.S78

103

47.342

15

218

4:00

73

9,530

5,16.-i

172

66

97

194

194

1,600

890

225

90,981

103

47.357

15

4:30

72

4,688

5,15S

171

67

97

194

190

1.200

,880

235

91,084

103

47,372

15

226

5:00

72

9,8,52

5,164

171

62

97

190

1.S5

1,463

800

235

91.187

103

47,386

14

230

Total

640

^1.272

41,272

1,547

512

859

1,695

1.705

11.063

7,405

2,080

823

823

117

117

1.856

.\vcrage...

71.1

171.9

171.9

171.9

128*

95.4

1SS.3

1.S9.4

2,765.7.5*

822 . 8

231 . 1

205 , 75t

205.7.-.t

29.25t

29.2.5t

206

•Per hour. vKilowatt.s

of output, the speed of the engine under
all conditions of load, and the cost of
fuel per kilowatt-hour delivered to the
switchboard.

The engine tested was a vertical, two-
cylinder, single-acting machine, with cyl-
inders 20 inches in diameter and a stroke
of 30 inches; it operates on the four-
stroke cycle. The engine was direct
coupled to a 250-volt, 175-kilowatt, di-
rect-current generator; the speed of en-
gine and generator was 175 revolutions
per minute.

The compressed air for injection and
starting was furnished hy a belt-driven
three-stage Ingersoll-Rand compressor,
driven by a 25-horsepower General Elec-
tric motor; this motor also furnished
power for a Gould triplex pump which
circulated the jacket water through the
engine jackets.

A shop load of lights and motors was
used in the tests, and it was maintained
as near constant as possible by hand
manipulation of the rheostat. The en-
gine had run about 2800 hours under
load when the tests were made.

The fuel oil was furnished to the en-
gine oil pump by gravity from an ele-
vated tank equipped with a sight-feed

to restore the level was weighed at each load tests and Table 2 is a summary- of

reading. A chemical analysis of the fuel all of the tests. The principal result:

oil used showed 19,149 B.t.u. per pound: of the tests are plotted on the chart, Fig.

the specific gravity was 29.9 degrees 2, for ready comparison and concise

Fic. 1. Representative Indicator Dl.^cR.^.MS Taken Dlring Tests

Baume, making the weight 7.295 pounds presentation. Fig. 1 shows exact fac-

per gallon. similes of some representative indicator

All readings were taken simultaneous- diagrams taken during this series of

ly, and a log of each run was made, tests.

November 21, 1911

POWER

779

SIMMARV OK ATLAS ENGINE TESTS

Duration of test in hours
Load in kilowatt-hours hy

switchboard meter

Kilowatts to compressor by

wattmeter

Transmission losses to com-
pressor, 23.6 per cent

Net kilowatts used by com

pressor

Brake horsepower used b.\

compressor

Net kilowatts delivered to

line

Net effective horsepower
Generator edicieney. per

cent, manufacturer's rat

ine

Net Drake horsepower

Revolutions of engine per

minute

Fueloil used, pounds per hour
Pounds oil per kilowatt -hour
Gallons oil per 100 kilowatt

hours
Pounds of oil |)er brake

horsepower-hour

Gallons of oil per 100 brake

horsepower-hours . . ,
B.t.u. per brake horsepower

hour

Thermal efficiency of en

gine 2.i4,">

100.
174.

B.t.u. per b.h.p-^

Fuel cost of 100 kilowatt

hours in cents oil at 2 cent

per gallon

132.0
23.6

18.1
24.25

173.13
Sl.O
0.71

9.73

0.47:

6.47

0,038.0

28.1,5

9.6
0.4
6.44
J,00O.0
28.2

200.4
29.6

6.9S
22.6:
30.31

177.71

23S . 2;

172.9
120.4
0.68

9.2'

0.48

6.3

8,808.0

28.9

205.7.5

29 . 2.5

6.91

22 . 35

29.94

183.4
245 . 75

9.115.0
28 0

249 0
31.0

10.15
0 . 503

9,632.0
26.4

Points of Observo+ion, Kilowatt's
115 155 178 185 E25_

Pounds ofFuelperB.Hp.-Hour^ ^ 19150 B.tu. per Pound

_l__l

-1— t-

50 75 100 125 150 175 200 225 250 275 300 325 350
BroKe- Horsepower

Fic. 2. Chart of Principal Results of Tests

distinct parts, as shown in Fig. 3; first.
the regular compression cui^'e C, to the
point of ignition; second, a sharply ris-
ing part E, during combustion, and, third,
a smooth compression curve F, of the
hot gases. As Mr. Pannely's diagram
has a continuously smooth compression

LETTER

Mr. Warmely'.s Looped In-
dicator Diagram

The indicator diagram in Fig. I has
appeared in Power twice with Ingenious
explanations of the loop. Mr. Parmely,
who gave the diagram originally, thought
that the cause was that the Ignition was
extremely late and the jacket water
tooled the gas, decreasing the volume
land therefore the pressure) of the gas
until ignition had occurred. That late
ignition does not produce a noticeable
loop from this cause is shown by Fig.
2, which was also taken from a pro-

curve, I must differ with Mr. Austin.
Besides, the definite combustion lines
shown would indicate that the mixture
had not been previously burned during
compression.

I should say that the loop in the dia-
gram was caused by a defective reducing
n:otion whereby the indicator drum was
lagginp behind the piston. When the
piston was at the end of its stroke, the
drum still had some distance to go; as
a consequence, the expanding charge de-
creased in pressure while the drum fin-
ished its stroke. This can be plainly
seen by looking at the diagram closely.
Had the reducing motion been in syn-

ducer-gas engine with ignition delayed
as far as possible.

Mr. Austin (October 24 issue) ex-
plains the loop on the prcignition hypoth-

Sc'Ole S40 Poundi
per Inch

Fic. I. Mk. Parmely's Diagram

csis. My experience with gas-engine
diagrams showing preignition leads me to
believe that a compression curve during
which preignition occurs always ha<» three

Fic. 3.

chronism with the piston, the expansion
line would have followed the compression
curve on the return and the combifstion
lines would have appeared much later
in the stroke, as was to be expected
with a spark 10 degrees after dead cen-
ter on an engine using producer gas.

Fig. 3 was taken from a two-cylinder
engine using artificial gas, the other cyl-
inder carrying the load and preventing
the engine from stopping.

G. W. MUNRO.

l.a Fayette. Ind.

For the purpose of studying the flow
of the more important rivers in Iowa,
the Stale geological sur\'ey has recently
entered into cooperation with the United
States Geological Survey. The pos-
sibilities of developing the water power of
Iowa have aroused much interest, and
the records now being made will be nf
value not only in planning for the utiliza-
tion of water power but also In devising
measures for preventing floods. TTic river
valleys are subject to severe overflow.
The subject of the pollution of the
streams by sewage is also becoming in-
creasingly important and in this connec-
tion the low-water records arc valuable
in indicating the allowable degree of
such pollution.

POWER

November 21, 1911

When about to blow down a horizonia
return-tubular boiler carrying a steam
pressure of 120 pounds per square inch, I
found that the pipe which led from the
bottom of the boiler through the rear
boiler-room wall into the cellar, where
the blowoff valves were located, was
clogged with mud and scale. The boiler
was equipped with a circulating pipe, as
shown in Fig. 1.

I closed the valve A and as the valve
B was open. I opened the valve C. Finding

Fig. 1. CoNNKCTioN of Circulating Pipe

I think the rods are a good thing as
the pipes are not always safe even if
the valves are, and while not always
practical they can in many cases be used
to the absolute safety of the attendant
from a painful if not fatal injury.

The gate valves do not leak and have
given no trouble whatever after five
years of hard service.

George Drewry.

Brantford, Ont., Can.

An Emergency Reamer

I was running a Corliss engine when
the crank pin began to work loose. It
was fitted into the crank disk with a
slight taper and was held in place by a
thin nut on the back side of the crank.

In the accompanying sketch plans are
shown of a draft gage that most anyone
can make out of scraps found about the
plant. Take a piece of heavy tin or
vanized iron about 15 inches square and
cut it out as shown to make a box 6 and
3 by 4 inches and bevel it on a straight-
edge through A R, B D, C D and A C.
Turn down the flaps M and securely
solder the joints. Then cut a piece to
form a middle partition and extend this
piece to within 14 inch of the bottom and
solder in place. When this is done turn
down the flap on the section M and bend
through F C to form the top of one side
of the box. Then solder it to the side
and partition. If tight, the box is ready
for the U-tube which is connected at one
end with the top outside of the closed
side of the box. Fasten a piece of }4t-
inch tubing to it for connecting to the
stack.

Take the dial, hand and gear from an
old steam gage and remove all of the old
figures. Then make a support for the
dial as shown and fasten it to the back
of the dial and the front of the gear
frame. Then attach the gear frame to

the pipe still clogged, I closed the valve
C. intending to force city water through
the pipes after the day's run. When
about to open the valve A to restore the
circulation if possible, the scale came
down with a chug, forcing the crown or
bonnet from the valve and badly scald-
ing the upper part of my body.

Homemade Reaaier

Fig. 2. Valve-stem Extension

I had plenty of time at the hospital
to plan a different blowoff arrangement
and when I recovered I made extension
rods, as shown in Fig. 2. each having a
crank at the outer end. The other end
was made with a Y-fltting which en-
gaged with the handwheel of the valve
with a washer and cotter pin placed on
the inside of the handwheel.

The nut was removed, and when the
pin was driven out it was found to be
cracked two-thirds of its diameter near
the middle of the tapered section. The
Iiole was calipered and found to be true
on the back side but was worn nearly
I 32 inch oblong on the front side. .\
new pin was obtained and an effort made
to grind it into a fit.

The job worked well for about a year
when evidences of the old trouble began
to show itself. I decided to make a
reamer, and having no tool steel of suffi-
cient size and being in a rather isolated
place, I took a piece of machinery steel
and made a reamer as shown in the ac-
companying sketch. It was case-hardened
and served to make a clean, round hole
in the crank. A new pin was put in and
has been giving good service ever since.
R. S. Livingston.

Deweyville, Tex.

the small pedestal so that the center
line of the gear will come upon the cen-
ter of the box and attach it to the bot-
tom of the gear where the expansion tube
was fastened. This extends to the cen-
ter of the open end of the box, and by
means of a link motion connect the lever
to the vertical float rod. The longer the
levers the better, as they will not have a
tendency to bind the rod against the side
of the guide as it moves up or down.
After the lever and links are attached to
the float rod, fill the box with water until
the float is a little above the center of
the box, and cover it with light, thin oil.
Then set the gage hand at the bottom of
the dial and calibrate to tenths of an
inch by comparing with a standard U-
tube. The intervening spaces may be
laid off in proportional parts, tenths or
twentieths, to suit the individual's fancy.
An ordinary 5-inch dial will give a scale

November 21, 1911

POWER

781

of about 14 inches to each inch of water
pressure, making about ',< inch to each
one-hundredth.

The float will not respond at once to
changes of pressure, owing to the large
column of liquid that must be moved,
but it will be found to be very accurate
if there is no friction or lost motion ex-
cept at or close to zero. The instrument
is readily portable as the contents may
be poured out at any time and need only

E

E

&

A

B

' 1

F

'c

D

n-tx.

E

E

Details of Draft Cage

to be set in an approximately level posi-
tion and filled with water until the hand
points to zero to be ready for service
again. It may be mounted in a dust-
proof wooden case and set up at any
convenient point in the boiler room. When
rvicely finished it makes a ver>- respect-
able aopearance.

E. P. Rice.
Asylum, Miss.

Improvised S!;ite Saw

The accompanying sketch shows an
improvised saw which was used to cut
a slate panel for a switchboard. A hack
saw was broken into a number of small

A

n

^^ e

«

e

s
c

•
•

^

y

y

X.

yr

Slate Saw

pieces and clamped between two 1x3-
inch strips of wood by means of screws.
The hack-saw pieces were set to project
from the edge of the boards in the form
of triangles of about Vi inch in htght.
Two guide strips were held by clamps
to the slate panel, as shown, and the

saw was worked back and forth between
them. Water was used in doing the work
of sawing.

J. J. O'Brien.
Buffalo, N. Y.

An Emergency Air Chamber
A blow with a sledge hammer, wielded
by a discontented laborer, demolished the
air chamber of a lOxlO-inch duplex,
boiler-feed pump and I was called in to
"do something." It was impossible to
get a new air chamber from the makers,
and. after taking a few measurements, I
had two i;<-inch steel disks bored and
tapped for a 4!<-inch pipe and turned up

Air Chamber for Pit\ip

to 10 inches outside diameter. These
rings were marked off for the bolt holes
from the flanges they were to replace.
Meanwhile, three 4'';-inch screwed nip-
ples, a 4''-inch tee and a 4!^- to 8'/-
inch reducing nipple were found and
fitted together with white-leaded joints,
as «hnwn at A, B. C and K in the ac-
companying illustration. A piece of 8' ,-
inch, outside diameter, steel steam pipe
was cut off 18 inches long and screwed

to fit the large end of the reducing nip-
ple, and was plugged by a brass plug,
which was turned with a slight taper.
The flanges were drilled for bolt holes
and screwed onto the nipples A and B.
The taper plug F was calked and burred
over with a blunt chisel and a peen
hammer, and secured in place by the
;ii-inch screws G. The air vessel was
placed on the pump and connected to
the feed line in something under 1 ' j
hours after the job had been commenced.
The pump is still running with this air
chamber, for a new one has not been
ordered yet, and is not likely to be.

A better job could have been made by
screwing a cap over the top of the pipe
instead of plugging it, but there was
nothing in the stores or about the works
to fit.

John S. Leese.

Manchester, Eng.

Controller Brush Holder

In the accompanying illustration is
shown a side view of an arm and brush
holder which I have made as a substitute
for the old form used on the Morgan
chain controller.

New Brush Holder

The old form had two small ears and
springs on the sides and as soon as the
brush wore down they started to arc and
burn oPF the ears and springs.

The brush holder illustrated herewith
has no such delicate pieces to give trouble
and will last indefinitely.

E. H. Marzolf.

Youngstown. O.

Remote Control of Water
Wheel Gate

Several years ago I was employed in
a textile mill operated by both steam
and water power. The wheel house was
at some distance from the engine room
and as it fell upon one of the assistant
crcineers to open and close the gates of
(he lurbincs, the engine-room force was
handicapped by the loss of a man just
at the times he was most needed.

After several unpleasant experiences.
It was decided that some method of con-
trolling the turbine gates from the en-
gine room was imperative. The master
mechanic easily solved the problem as
shown In the accompanying illustration.

782

POWER

November 21. 1911

The gate wheel in the engine room is
mounted on a shaft that is supported by
ordinary hangers. On the wheel-house
end of the shaft there is a bevel gear that
meshes with a gear on a shaft extended
up from the original gate-wheel shaft.

In order to tell in the engine room
just how much the gates are opened, a
graduated board is fastened to the wall
beside the gate wheel and an indicator

construction; the quality of labor em-
ployed, and the temperature of the fur-
nace.

A fourth factor would be whether the
furnace is used continuously, for every
time the brickwork' cools off it will be
racked, due to contraction. Firebrick
should be kept dry, both before and after
installation. One of the best methods of
laying brick in arches is to lay them

Arran'ce.ment of Waterwheel Control

finger moves up or down the side of this
board when the gate wheel is turned.
The. indicator finger is attached to a
we^t concealed in a groove at the back
of the gage board and a chain from the
weigfit passes around the gate-wheel
shaft in a spiral groove that prevents
it from creeping on the shaft.

The figures on the board are cut from
calendar pages and glued on evenly.
Then the whole board is gone over with
shellac. It is difficult to tell that the
figures are not nicely painted on, and the
result is much more pleasing than if
an amateur painted the figures.

This arrangement has proved success-
ful and it can be installed at little ex-
pense in almost any plant.

W. L. Whitmarsh.

Phenix. R. I.

Firebrick Arches

The best firebrick which can be bought
are the cheapest to use in build-
ing arches. A brick made of good ma-
terial will glaze over and not break
readily, but one of poor material, al-
though it might be perfectly made, will
chip, scale and waste away.

The life of an arch depends on three
factors: the material entering into its

dry, and dipped in thinly mixed fire-
clay for the side and bridgewalls.

Each row of brick should be gaged to
a certain thickness so that there may be
no loose brick in the arch, everj' brick
keying up solid.

The illustration shows an igniting
arch for a 500-horsepower water-tube
boiler fitted with a chain-grate stoker.
The key bricks are ready to be driven

Keys Ready to be Driven Home

down, no fireclay having been used. As
snon as the keys are driven, a thin wash
of clay and salt should be worked into
the cracks between the brick, making the
arch a solid mass.

Such an arch when made of the best
material and properly made will stay up
from 10 to 14 months, using the boiler
24 hours per day.

To rebuild the arch, side walls and re-
lieving arch the cost will be as follows:

LABOR AND .M.XTEKIAL.-

.580 9-inch brick.s at $.iO \>kt thousand ... 117.49

44 WR'Jge brick at $30 per thousand. ... l.'.'.i

300 pounds fireclay at %.i per ton 0.45

44 hours' labor at 60 cents per hour. ... 26.40

20 hours' labor at 30 cents per hour. ... 6.00

Tot;il $.-.l..S7

A rule I follow is to build all arches
dry and later fill in all cracks with salted
fireclay. I also gage all brick for the
arches so that all rows across the arch
are of equal size. I key an arch hard
enough to be lifted from off the form
when the keys are driven home. I never
mix different grades of brick in an arch,
but have them all of one grade and man-
ufacture.

I insist on having a perfect skewback,
for without a good foundation the result
vill be a failure.

Brick for side walls and bridgewalls
should be dipped in a salted batter of thin
clay and be hammered well in place,
making as thin a joint as possible.

Bricks, when subject to great heat, ex-
pand and provision should be made for
this expansion upward by building the
relieving arch independent of the main
arch.

I always warm up new brickwork
slowly and evenly to insure equal ex-
pansion and expulsion of moisture.

For estimating purposes on firebrick
work I have found that 300 pounds of
fireclay will lay 1000 brick when a close
joint is made; 85 pounds of fireclay is
equal to 1 cubic foot and I cubic foot
of fireclay brickwork weighs 150 pounds.
One cubic foot of brickwork requires 17
nine-inch straight brick, and 1 square
foot of 13'j-inch wall will require 21
brick. One square foot of 9-inch wall
will require 14 brick; 1 square foot of
4',; -inch wall will require 7 brick.
Frederick L. Ray.

Louisville, Ky.

Repaired Broken Cylinder
Head

A certain steam plant had, in addi-
tion to the electrical units, a 15-ton re-
frigerating machine and a piston-valve
engine.

One morning the assistant engineer
failed to drain the cylinder properly and
on starting, as the engine made its back-
ward stroke, it knocked the cylinder head
out, smashing it about as shown in the
accompanying sketch. I made a steel
band i^ inch wide and ' < inch thick. It
was '4 inch smaller than the head to al-
low for turning up in a lathe ?., inch
smaller than the head. I then filled the
cracks with No. 1 Smooth-On, and shrunk
the band on the head. After giving it a
little time to set, I replaced the head
and on starting the engine was somewhat
surprised to see that the head did not
leak.

When I left the plant a year later, the
head was still in sen'ice.

D. E. .\DEN.

Wilburton, Okla.

November 21, 1911

POWER

783

Engine Knocks

In the October 3 issue, page 524, W.
A. Mills asks for the cause of the knock
in the low-pressure cylinder of his tan-
dem-compound engine, which intensifies
as the engine picks up its load.

I would advise him to disconnect the
crosshead from the connecting rod, hav-
ing previously marked the limits of travel
on the guides. Then push the crosshead
to the ends of the guides as far as it
will go in either direction. He may find
that there is no clearance at the crank
end and that the low-pressure piston is
striking the head at the end of the stroke.

If there is clearance at each end
of the cylinder, there may be such
a difference that excessive compres-
sion is caused at the crank end. Un-
equal valve settings will also cause ex-
cessive compressions.

If there is nothing wrong with the
clearances and valve settings, next ex-
amine the valve gear for excessive wear
and slackness. This being found right,
the cylinder heads should be removed
and the piston, junk rings and follower
plate examined for looseness.

A prolific cause of mysterious knocks
is side play in the piston-ring groove.
Examine the cylinder surface for shoul-
ders or ridges which would catch the
piston or rings at the stroke end. If
nothing is wrong here, Mr. Mills can
dismiss the low-pressure cylinder and go
over the rest of the engine.

To go through the complete catalog
of whys, wherefores and possible causes
of engine knocks w'ould fill a complete
issue of Po^Jl■ER. Let Mr. Mills look up
his back numbers for causes of pounds
as they will mostly be found in them.
But, just a whisper: Is he overloading
the engine?

John S. Leese.

Manchester, England.

Crosshead Pins

In Power for September 5, page 371,
Lioyd V. Beets brings up the question
of the size of crosshead pins. Undoubt-
edly engine builders have often made
these pins much too small, sometimes
with a false idea of economy but more
often they are small because the engine
ij> sold to work with a higher steam pres-
sure than that for which it was designed.
Again, it often happens that an engine of
standard design is required to work with
a pressure 20 pounds higher than it was
designed to work with, and building an

engine with larger and stronger parts
throughout would make it too costly;
therefore the standard engine is sold.

In designing a crosshead pin only the
total load on the piston and the limiting
pressure per square inch allowable in
good practice are known; from these data
the diameter of the pin can be obtained
from the formulas found in most text-
books.

It is good practice to let the allow-
able pressure on the pin vary between
1300 and 1400 pounds per square inch;
the safe stress on the pin is about 5000
to 6000 pounds per square inch for
wrought iron, and from 6500 to 7500
pounds per square inch for steel. If
the pressure per square inch on the pin
is much in excess of these figures there
is the danger of the film of oil between
the pin and its brass becoming squeezed
out. Should this happen, excessive fric-
tion will result and cause rapid wear-
ing of the pin and brass, producing a
knock and necessitating the frequent ad-
justment of which Mr. Beets complains.

As to his statement that the crank pin
and the crosshead pin should be of the
same size, it will at once be seen that
the operating conditions of the two pins
are not at all similar; therefore the limit-
ing pressure per square inch would not
be the same for both pins; this would
cause a difference in the sizes of the
pins. As the rubbing surface of the
crosshead pin is small and when the
composition bearing works against
wrought iron or steel, the allowable In-
tensity of pressure per square inch of
bearing surface can be high, whereas in
the crank pin the velocity of rubbing is
much higher and the allowable intensity
of pressure per square inch of bearing
surface must be lower.

In designing a crank pin the same data
as for the crosshead pin arc available;
that Is, the total load on the piston and
the limiting pressure per square inch al-
lowable in good practice. The diameter
of the pin, if it Is overhung, can be found
from well known formulas.

Limiting the pressure per square inch
from 800 to 900 pounds for engines of
slow rotational speeds, is good prac-
tice, but for high-speed engines this
value should be between 500 and 600
pounds; the safe stress on the pin is
about 6000 to 8000 pounds per square
inch for wrought iron and 9000 to 12,000
pounds for steel; the length of the pin
is usually about 1.4 to 1.5 times its
diameter.

If the crank pin is formed in a crank
shaft then its diameter is usually the
same or slightly larger than the diameter
of the main bearings. In this case the
strength is ample and the length has
only to be obtained from the values of
the limiting pressure per square inch.

In an engine designed on these lines
for 170 pounds per square inch working
pressure, the cylinders being 12 and 20
by 21 inches and arranged in tandem,
the crosshead pin is 4 inches in diameter
by 6'4 inches long and the crank pin is
5 inches in diameter by 7'4 inches long;
thus the difference in the two pins is
seen and it is evident that had they been
made of equal size either the crank pin
would be too small or the crosshead pin
too large.

Unless the load is too great, it is usual
to put in smaller liners and pistons than
the standard for such engines as have
to work with a steam pressure higher than
that for which they are designed; in this
way the reciprocating parts do not have to
transmit too great a load ; therefore the
stresses and pressures are not excessive.
Ja.mes Cannell.

Stanford-Ie-Hope, England.

F",ngineers' Reference Book

In the issue of October 17, Phil Lighte
wants information on starting a reference
t-ook. He wishes a pocket-size book of
ti.e loose-leaf variety. The one great
trouble with books of this description is
that they are not made thick enough to
hold a great many pages. As material
for his book must be filed under the
proper headings, and as each heading
should have at least a whole page for
itself, the book will soon burst with
pages, most of which contain very little
information. The writer overcomes this
with an extra set of index cards and a
box to hold Ihcm. Anything which is
used often is kept in the book, but other
material not so important is filed in the
box where it may be found when wanted.

784

POWER

November 21, 191 1

Everything read should not be copied.
Many articles published, although written
in good faith, may not be the best prac-
tice.

Everything should be copied carefully,
thoroughly; many times I have picl^ed
out a formula to use only to be brought
up sharply as to whether a certain di-
mension should be feet or inches.

The great mistake in starting a note-
book is to try to copy too much. To copy
a long table or the gist of a long article
takes time. It may work at the start
but as a person's enthusiasm wears off
the value of the notebook is apt to de-
teriorate.

My practice is always to note down the
source of the information for future
reference in case of any doubt as to the
article. If the article is short the whole,
or the important part, may be copied.
As a rule, an outline of the article, such
as is printed in the Hill magazines, is
all that goes in the book. If the book or
magazine is my own it may always be
referred to later, and in any event it may
be obtained from a public library.

Occasionally I copy all of some article
into my book, but not unless it is of great
importance or something that cannot be
found in the handbooks. After all, the
handbooks contain a good deal of reliable
information and are hard to beat.

Many tables that I copied in the first
burst of enthusiasm have afterward
proved to be common copy matter for the
textbooks and catalogs. My advice to
Mr. Lighte is to take it easy at first and
not overdo it. The scope of the book may
easily be increased later if the owner
has the time and patience, but do not
start off at a pace too swift to hold.

John Bailey.

Milwaukee, Wis.

Water in Red Hot Boiler

Replying to H. R. Rockwell's ques-
tions as to turning cold water into a
red-hot boiler, I will relate an in-
cident that occurred with an over-
heated boiler.

The boiler was 9 feet 6 inches by 30
feet and carried steam at 160 pounds
pressure per square inch. One day the
boiler got red hot, due to low water. The
stoker started the feed pump full speed
and had got the water up to the bottom
gage cock. The following Sunday the
engineer examined the inside of the
boiler and found that in each flue the
seam just in front of the bridge had a
drop in at the top nearly 2 feet long
and was depressed about '/> inch.

Disastrous boiler explosions have oc-
curred by allowing the tops of the boiler
flues to get red hot and by their becom-
ing bulged in by the pressure inside the
boiler. If the cutting in of boilers is
carefully done and the pressures in the
boilers slowly equalized, there is no
danger, but unless this care is taken the

operation is very dangerous. It is com-
mon practice for a boiler to be opened
out on to the main when its pressure is
cither above or below that in the main,
but all steam valves must be opened very
cautiously so that the steam pressures in
the main and in the boiler will slowly
equalize. It is the accumulation of water
above the stop valve that forms one of
the dangers of opening a boiler stop
valve suddenly, and whether the pres-
sures be equal or not there is the dan-
ger of the water being driven violently
into the boiler or into the steam main.
There is a large volume of water in a
boiler which is at the same temperature
as the steam and if, by rapidly opening
the stop valve, the pressure is suddenly
reduced, a certain amount of this water
becomes instantly converted into steam,
and the steam generated at the heating
surface of the boiler in endeavoring to
escape lifts the water above it and the
result is a severe water hammer against
the top plates.

The reason the explosion of one boiler
causes the others to explode is be-
cause the steam in them is suddenly
liberated. This reduces the pressure in
the boilers, and causes the sudden gen-
eration of steam throughout the mass of
water, and the generation of such a large
volume of steam causes the water above
it to be projected with great velocity and
energy against the containing walls of
the boiler; this water-hammer effect is
responsible for the fracturing of the
boiler.

If a throttle valve shuts off steam com-
pletely and no steam gets into the cyl-
inder, an engine cannot increase its speed
and it will eventually stop. An engine
runs because there is a difference of
pressure on the two sides of its piston,
and if there is no leakage of steam into
the cylinder the condenser will establish
a vacuum on both sides of the piston,
it will be in equilibrium, and the engine
will stop.

V. E. Clarke.

Manchester, England.

In reply to Mr. Rockwell's queries in
the September 12 issue, I would give the
following as my opinion on the first ques-
tion relating to turning water into a red-
hot boiler.

The experiment has been tried several
times on this continent and in Europe,
but the boilers would not explode. As-
sume that the boiler is heated to a bright
red; as there is no pressure inside, there
is nothing to explode the boiler.

If feed water is fed to the boiler the
heat m the plate is readily absorbed by
the water, which will roll about in a
more or less violent manner. The boiler
will rapidly cool off, setting up all kinds
of strains in so doing, and the prob-
ability is that it would be ruined.

H. Powers.

Montreal, Can.

Retubed the Condenser

With reference to P. P. Fenaun's arti-
cle in Power of September 26, relative
to the method he employed in taking
care of the expansion of the tubes in
his surface condenser when it was op-
erating on intermittent loads, I recently
visited a power plant having a specially
built condenser, designed to handle in-
termittent loads. As in Mr. Fenaun's
plant, there would rarely be a constant
load, and it came to the condenser in
jerks.

The tubes were expanded into the
tube plates at both ends, doing away
with all tube packing. One end was
arranged with a standard water box, etc.,
but the other end was arranged with
a floating-head. The tubes are expanded
into the tube plate at the floating-
head end, which rests on the shell and
slides backward and forward as the load
differs, thus taking care of the expan-
sion and contraction of the tubes.

N. OwiTZ.

New York City.

FlyAvheel Explosion at West
Berlin

The editorial in the October 3 issue,
entitled "Offhand Verdicts," interested
me, especially the term "absent treat-
ment."

As already stated, the chief engineer
(who was more than a mile away from
the West Berlin plant when the accident
occurred) found that the accident was
due to No. 1 generator becoming motored
by the reversal of the current through it
from No. 2 generator, which carried a
slightly higher voltage; also, that the
circuit-breaker failed to open because the
latch had become expanded by abnormal
heat.

The theory that the engine was wrecked
by the generator to which it was belted
becoming motored by the reversal of the
current through it from the generator
of the other engine may seem plausible
at first thought, but the fact that the
;irmature windings were torn loose and
in a tangled mass radiating from the
center of the shaft explodes that theory
because the machine would cease being
a motor before reaching that stage of
destruction.

The theory is advanced that the circuit-
breaker failed to open, owing to the
abnormally high ctmospheric temperature
of a few days preceding, which had ex-
panded the latch. This is offset by the
fact that the accident occurred well along
after sundown, when the temperature
would be such as to contract the parts
of the circuit-breaker to their normal
size.

The plant was erected less than 13
years ago, and I have often seen one
engine furnishing all the power required.

November 21. 1911

POWER

785

I was the author of the first account
of the accident published in Power and
wrote the account, thinking the matter
would be of interest to the engineering
fraternity. No thought of censuring any-
body entered my mind, because from the
"jolts" received during many years of
experience with machinery I do not con-
sider any mechanical device infallible.

I still hold to the same opinion ex-
pressed in my first article, for what I
saw at the plant before and since the
accident leads me to believe that the
trouble was caused by the governor belts
running off the pulley.

J. W. Parker.

Clinton, Mass.

To Prevent Standpipe Freezing

Replying to Thomas Nicholson's ques-
tion, I would suggest that he keep the
surface of the water in continuous mo-
tion in the standpipe during cold weather
by allowing a stream of water to fall
upon it.

A covering, say 6 inches thick, of com-
mon straw all around the standpipe is
sufficient to prevent the water from fall-
ing below the freezing temperature. The
straw should be held in place by thin
boarding, covered on the outside by tar
paper. A less thickness of straw may be
sufficient, but this would depend upon
the exposure of the standpipe.

John Zetterlund.

Eskilstuna, Sw^eden.

Massachusetts License Laws
and Examiners

The letter by C. C. Harris, in the is-
sue of October 10, contains some ex-
cellent ideas regarding the Massachusetts
license laws, but he is mistaken in think-
ing that special licenses apply only to
second-class plants and below, as the law
only says that special licenses shall not
be given to one who is to have charge of
plants of over 150 horsepower, and many
first-class plants are operated by hold-
ers of special licenses. Why should it be
necessary to limit these licenses to six
months, or any other specified time, as
recommended by Mr. Harris?

Suppose, for illustration, that an en-
gineer is running a small plant consisting
of a horizontal tubular boiler and a 60-
horsepower slide-valve engine, with the
usual pump, etc. Being over 50 horse-
power, this would require either a spe-
cial or a second-class engineers' license.
Having been examined and found com-
petent to care for all parts of the outfit,
he is given a special license to have
charge ot and operate this particular
plant, and in all probability he is capable
of meeting any emergency which may
arise in connection with its operation.

Why does Mr. Harris believe it nec-
essary for the protection of the public
that this man should within six months

pass an examination covering all types
of engines, boilers, pumps and other ap-
pliances found in any plant of 150 horse-
power or under, to say nothing of the
"impractical" questions which we are
told form a part of every examination?

Failing in this, he would be obliged to
give up his position.

Personally, 1 know men who have op-
erated first-class plants on special li-
censes for a dozen years without caus-
ing either inconvenience or danger to the
public.

Roy W. Ly.man.

Ware, Mass.

In this discussion there should be no
confusion of the merits and imperfec-
tions of the law with its administration
by the inspectors. If the inspectors make
mistakes, that is not the fault of the law,
and to argue against the law on that
basis, as is sometimes done, is hardly
logical. I believe the law is a good one,
but not yet ideal.

Mr. Harris says there are many engi-
neers who would like to change the law
and abolish the special license. This
would seem to be an amendment in the
right line. But Mr. Harris and the many
others ought to know that kicking and
growling about this thing in the boiler
room will be of no avail. If these men
want the special license done away with,
why not go at it?

As for the inspectors, they are human
beings and therefore liable to error; but
I know they are subject to wilful mis-
representation, and that thereby their
errors are magnified and multiplied. I
know of cases where men lied about their
examinations — reporting questions and
conversations which never occurred.
When a man comes back rejected, take
his story with a grain of salt.

Mr. Harris thinks the examination
should be wholly practical. Possibly his
picture of an engineer is a man who
can open and shut valves, squirt oil and
shovel coal; but the engineer of that
type is a back number. In every trade
today the requirement is for a man who
knows the underlying principles of the
practice, who uses his brains and who
understands the relation of his work to
that of others. This is especially true
of the stationary engineer. He ought to
know boiler design, not because he has
to design boilers, but because he ought
to know that his boilers are designed cor-
icctly; and he ought not to have to wait
for an inspector to come along and point
out the faults.

A new plant just installed in Boston
has boilers designed for 180 pounds pres-
sure. The law requires two valves with
a drain between them upon boilers al-
lowed over 135 pounds pressure per
square inch. This plant was installed
with only one valve per boiler. A wide-
awake engineer would have seen this
fault and have pointed it out in time; but

in this case the boiler inspector was the
first to notice it. Most engineers have
seen serious mistakes in piping, in foun-
dations and in other items about the
plant, mistakes made by the designer
and left for the engineer to rectify. The
correction of these mistakes often calls
for keen intelligence and broad knowl-
edge. The "practical" rule-of-thumb
man is not able to meet the oc-
casion. In fact, the only man who
is practical in the best sense of the
word is the man who squares his prac-
tice with uptodate science. For this rea-
son the inspectors are perfectly right in
examining applicants upon "theoretical
matters."

Another claim that, at first thought,
might seem plausible, is that examina-
tions should be confined to matters of
safety. Upon second thought, most of us
will probably reject this, hut suppose
we do not consider the matter carefully
and safety turns out to be not such a
simple matter, after all. Disaster comes
in new and unexpected ways. Witness
the recent accident at West Berlin where
a generator motored and burst its fly-
wheel. A few months ago an examiner
wruld probably have been severely criti-
cized had he asked questions concerning
the parallel operation of generators or
the care of circuit-breakers. And yet, in
the light of what has happened, it seems
that merely on the ground of safety,
knowledge of such matters ought to be
required of applicants for second- and
first-class licenses. Because no one was
killed at Vest Berlin is no reason why
we should not heed the warning. There
are other plants where the same thing
may happen at any minute.

No man who does things without know-
ing why is really a safe man. Unless
he knows the theory of the operation he
may do very dangerous things. Receiver
pressure and its regulation might be con-
sidered theoretical questions, yet there
is at least one engine running in a dan-
gerous condition because a "practical"
engineer tried to adjust the receiver pres-
sure by lengthening the governor rod to
the high-pressure valve gear.

One regular examination question is,
"How does a pump lift water?" It is a
temptation to class that as a theoretical
question in no way related to safety.
Yet not until one understands the prin-
ciples underlying this action can he un-
derstand how an engine cylinder can take
water from the exhaust pipe and smash
things up. When it is recalled that one
engineer smashed three engines in 15
minutes In this way, it is seen how vital
this question is in relation to safety.

Sicam engineering is by no means on
the perfection level. It is going up and
rapidly, too. As it goes, new problems
arc being opened up, many of them re-
lating to safety. The man who is con-
tent to plod along the way grandpa did, is
hardly a safe man. A safe man will not

786

be found putting cast-iron valves and
fittings in lines carrying superheated
steam. He regards water hammer as
one of the most serious dangers in a
plant and will carefully avoid it in every
way.

Mr. Harris furnishes an amusing in-
stance of inconsistency when in one col-
umn he condemns the orders to "stiffen
up" the examination and in the next com-
plains that certain engineers are running
plants "on the ragged edge." Worse
cases than that are not hard to find, Mr.
Harris. A certain holder of a first-class
license cannot read an indicator card, and
when told that the card showed his Cor-
liss engine had too much compression
he was at a loss as to how to remedy it.
There is another engineer who actually
does not know the difference between a
primary heater and the receiver of a com-
pound engine — and worse yet might be
told, only it would seem unbelievable.
There are first- and second-class engi-
neers who are satisfied with jobs as fire-
men— a tacit admission of their own in-
capacity.

The orders to "stiffen up" were needed.
Mr. Harris wonders who gave the orders.
I will tell him: It was Common Sense.
Willi A.M E. Dixon.
Maiden, Mass.

Wire in Sight Glass

In the October 17 issue, page 598, is
a letter by Mr. Sobolewski, showing how
he placed a wire in the sight glass of
a lubricator, thus causing the oil to run
up to the top of the wire, thereby keep-
ing the glass clean.

I have had the same trouble with the
sight glass of a lubricator on a steam
pump. The oil would flow over the side

POWER
Trouble with Leaking Tubes

In the September 5 issue, under the
caption "Trouble with Leaking Tubes,"
William Beaton gives Mr. Reimers some
very good advice as to the prevention of
leaking tubes. Having had the same
trouble as Mr. Beaton and having over-
come it by changing the position of the
feed-water inlet, I quite agree with Mr.
Beaton's statements.

November 21, 1911

stroke, but in the latter part of the stroke
the air resistance is greater than the
steam pressure, and the flywheel to help
the running makes a pull on the con-
necting rod or a lift on the crosshead.

If the compressor runs under, the
crosshead is lifted for the first part of
the stroke, but at the other end of the
stroke the pressure is downward and
there is little to choose, either way. In
the belt-driven compressor the crosshead

Wire in End of Needle Valve

of the nozzle and cling to the glass,
sometimes filling it.

To overcome this trouble I flattened the
point of the valve slightly and drilled a
small hole about ~?r. inch deep and then
inserted a wire as shown in the accom-
panying sketch. The end of the wire
was soldered in the point of the valve
stem and was made long enough to pro-
ject a little above the top of the nozzle.
Frederick L. Johnson.

Paterson, N. J.

Scale Collector Attached to End of Feed Pipe

However, I think I have an improved
method of delivering the feed water. It
is discharged into a cast-iron trough
which is suspended above the tubes,
The accompanying sketch makes the ar-
rangement clear. The piping inside of
the boiler is made up of tees, nipples and
plugs. This trough gathers a large
nmount of scale and needs to be re-
moved and cleaned when cleaning the
boiler.

Charles Fenwick.

Wapella, Sask., Can.

pressure will be downward for the whole
of both strokes if the compressor is run
under, and the pressure will be upward
if it is run over.

Frank Richards.
New York City.

Direction of Compressor
Rotation

In the issue of October 24, page 642,
.A. E. Peterson mixes me up rather than
otherwise. I saw one of the earliest
Corliss engines — about 1855, I think—
and its running under astonished me
about as much as if ! had seen a clock
running backward. It has always been
understood, I believe, that steam en-
gines are run under to relieve the cross-
head and guides of some of their pres-
sure and wear by a difference of weight
equal to double that of the crosshead
and the connected ends of the rods. Mr.
Peterson seems to assume that it is de-
sirable to keep all the pressure down-
ward.

In the case of the direct steam-driven
air compressor the argument works both
ways in either case, and there will be a
transfer of pressure from downward to
upward, or vice versa, in ever>' stroke. If
the compressor runs over, the pressure
is downward for the first half of the

Setscrew Came Loose

Mr. Stewart's article in a previous is-
sue of Power on safety stops brings to
mind an experience I had with a 750-
horsepower Corliss engine when the set-
screw worked loose in the governor pul-
ley. It did not allow the governor to en-
tirely stop as the friction of the pulley
on the shaft maintained enough speed
to prevent the safety cams from being
disengaged from the hooks, but the speed
was not enough to maintain a proper
cutoff.

I was standing within 20 feet of the
engine when the valve hooked up, and
by the time I got the throttle valve closed
the engine was going in the neighbor-
hood of 200 revolutions per minute, which
did not look good for an 18-foot flywheel.
J. W. Dickson.

Memphis, Tenn.

"V;'e have reached our present high
standard of operating efficiency," says
S. G. Pollard, superintendent of opera-
tion at the Cincinnati waten*-orks. "sim-
ply by taking advantage of the conditions
of our service, by putting and keeping
our plant in the very best condition and
by looking after all of the details of op-
eration, none of which is too small to
merit careful attention."

November 21. 1911

POWER

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Contents i

Wltherbec-Sherman's New Station

The Chiefs Pay

Surface Combustion In a Boiler

Coat .System for Power Plant Operation

The Ijirgest Turblni- In the World

PMIadelphlas Oldest Steam Engine

The Power of the Atlantic Elect

The Isochronous Governor

Sampllns Coal

The Bell Single Phase Motor

Power and Current In Three Phase
Circuits

Mr. Hawkins' Compressor Motor

Test of an Atlas IHosol Oil Engine

Mr. Parmelya I,ooped Indicator DlaKram

Practical lyetlera :

Blowoir Valve Burst.... An Emer-
(fency Ueamer. .. .Homemade Draft
Gage. ... Improvised Slate .'*aw....
An Emergency Air Chamlier. . . .Con-
troller Brush Holder. . . .Kemote Con-
trol of Water Wheel Gate.... Eire
brick Arches .... Repaired Broken
Cylinder Head "80

Dlacnsslon I.etters;

Engine Knocks ... Crosshead Pins
....Engineers* Ueferenc* Book.
Water In Red Hot Boiler...
tubed the Condenser .... Elywheel
Explosion at West Berlin. . . .To Pre
vent Standpipe Freezing. ... Massa
Cbnsetis License I.aws and Exnmln

ers Wire In Sight Glass

Trontde with I.enklnc Tiit>e« . .
rectlon nf Compressor Rotation
Setsrrew Cnme t>K)se 7«3

Editorials 7S7

nesting and Ventilating a Fartorr

A Homemade Water Heater

Westlnehouse Msrlne Redtieflon Gear. . .

Failure nf Scotch Msrlne Boiler

Oil in Exhaust Steam

There are comparatively few steam-
power plants where an economy cannot
be effected by returning the condensation
from the feed-water heaters or surface
condensers to the boilers.

This is particularly true where the
feed water is bought instead of being
drawn from wells, streams or ponds, for
besides the heat conserved by using the
warmer water from the drips or hot-
well, the cost of the water itself is saved.

But there is, in those instances where
no provisions have been made for the
separation of the oil from the condensa-
tion, danger in its use for boiler feed.
There is practically no danger from the
oil as long as it remains oil, but this is
not for a great while after it gets into
the boiler.

Several things happen to it then.
Subject to long-continued heat, a
part of it is distilled, leaving be-
hind a sort of tar which readily
gathers to itself some of the loose scale-
making matter in the water and thus
becoming heavier than the water, it set-
tles to the bottom of the boiler where it
attaches itself to the sheet as soon as
the water becomes quiet.

Wherever this mixture of tar and scale
touches the metal it adheres closely,
preventing the access of water and, if
over the fire, a burned sheet or tube is
certain.

Sometimes the oil enters the boiler in
the form of an emulsion which acts like
a varnish to the inner surface nf the
boiler, preventing actual contact between
the metal and the water. In its first
stages this varnish is so thin that it
offers little resistance to the transmission
of heat to the water, but it soon grows to
a thickness that makes the bagging of
the boiler a certainty.

If the oil in the exhaust steam is thor-
oughly separated from the condensation
which is returned to the boiler as feed
wafer, it will result in a great saving in
water as all that will be needed beyond
condensation will be the small percent-
age of makeup required to replace that
lost through IcaVaee. As the condensation
will be considerably wanner than the
wafer from wells, ponds or city mains,
there will be a saving nf the amount nf
fuel necessary to make up for the dif-
ference in the temperature of the water.

Incidentally, there will be another sav-
ing which, while of great importance. Is
not so readily measured. Freed from oil

and scale-making impurities, all trouble
and expense resulting from scale, foam-
ing, leaking tubes, burned and bagged
shell plates and tubes will disappear and
the necessity for frequent inspection and
cleaning will be avoided.

It sometimes happens that the regular
water supply is shut off for hours at a
time, causing great annoyance unless
there is some form of tank or reser-
voir used in connection with the feed-
water system, but with an efficient meth-
od of separation such a tank will permit
the shutting off of the regular supply for
several times the duration possible with-
out the separator.

Surface Combustion

Attention is called to the interesting
demonstrations by Professor Bone, de-
scribed on page 767. The mode of com-
bustion there exemplified has been ap-
plied to several industrial operations, in-
cluding steam making; a nine-foot boiler,
about which we hope soon to have more
extended information, being in success-
ful operation in the Yorkshire district of
England.

It is interesting to recall that Dr.
Charles E. Luckc, of Columbia Uni-
versity, described practically the same
process in a paper entitled "Liquid Fuel
Combustion," presented to the American
Society of Mechanical Engineers at its
spring meeting in 1902. He called if
"explosive combustion." He was search-
ing for a process whereby liquid fuel
might be burned under pressure in order
that the products of combustion might
be used in an engine. The gasified fuel,
with the requisite quantity of air for
combustion, thus forming an explosive
mixture, was introduced into the small
end of a funnel and ignited in the cone-
shaped portion. The flame took the
shape of a section of a spherical surface,
but did not fill the section of the fun-
nel, and increasing the velocity of the
entering gases only carried the flame far-
ther info the cone. It was a natural step
to throw in a handful of refractory ma-
terial to break the flame up and the
flamcless comhtistion demonstrated by
Professor Bone was prodticed. Later
experiments developed the fact that the
shape of the chamber was immaterial
and led to the introduction of the explo-
sive mixture of gas and air into a mass
of broken refractory material, as Pi^-
fessor Bone docs in his steam boiler and
muffler. The proccsR evidently has some

788

POWER

November 21, 1911

possibilities in connection with the con-
tinuous internal-combustion engine prob-
lem upon which Doctor Lucke was ex-
perimenting.

Expert Advice

The managers or owners of an im-
portant project in the power-plant field
do not hesitate to engage a competent
consulting engineer to advise and assist
them with the plans and specifications
and to inspect the work and materials
when they have no man of sufficient at-
tainments upon their own staff. The
reputable power-plant engineer is likely
to be entirely unbiased except by the
reasonable desires of his client, and his
broad experience enables him to show
the adaptability or unfitness of any piece
of equipment to the exact needs of the
work in hand. He is not likely to be in-
fluenced by the extravagant claims of
unscrupulous or too eager salesmen. He
is able to execute the plans in a satis-
factory manner, and to so write the
specifications that his client shall be
protected from an inferior article both
in material and workmanship. His
knowledge of contract law should en-
able him to protect his client from an ex-
pensive and avoidable encounter in the
courts. His intimate knowledge of the
honesty, reputation and reliability of the
various contracting firms should enable
him to select those firms which are
able to do the work or tc furnish the best
equipment. He is prepared to conduct
the acceptance tests with perfect fairness
to all concerned. He is, furthermore,
able to protect the contractor from his
client's hasty or ill-advised actions, and
thus save grief for both the client and
the contractor.

The relations between the owner, the
engineer and the contractor should be.
fully and definitely understood by all,
and it is the first duty of the engineer
to make sure that they are understood.
In some cases the engineers are a cor-
porate part of the holding company, in
which event there is little to be said. In
the general case, however, where the
owner selects a reputable consulting en-
gineer, the first procedure should be to
carefully prescribe the services which
are to be performed.

It is unwise for the engineer to promise
to serve in any capacity but that of ad-
viser; that is, his reports should be
of facts and his actions should take the
form of recommendations only. Here
his authority ends and he is not justified
in taking any arbitrary action not pre-
viously specifically prescribed unless
such action is immediately necessary for
the best interests of his client; then the
engineer should immediately inform the
owner of the action taken together with
the reasons therefor. It is not only the
duty of the engineer to prepare the
plans and specifications, but he should
be ready to instruct the owner as to the

reasons for his policies should the owner
so desire. The fullest and freest con-
sultation is advisable in all cases so that
the mutual understanding shall be com-
plete. The owner should then invite the
opinions of his operating engineers and
present them to his consulting engineer
for his consideration.

It is the duty of the engineer to fairly
and firmly inspect the work and ma-
terials furnished by the contractor to
make sure that they comply with the
requirements and with the intent of the
specifications. It is a mistake to ar-
bitrarily enforce requirements which are
obviously unfair or unreasonable, and a
contracting firm should refuse to bid on
specifications which contain requirements
which would work a hardship upon it.
Notwithstanding these facts, it sometimes
happens that clauses which admit of un-
fair interpreaation are inadvertently in-
cluded in the specifications. It is then
the duty of the engineer to read the
intent of the specifications rather than
the letter.

The owner must expect some disap-
pointments; the most carefully executed
plans of the most competent engineers
are liable to result in minor disappoint-
ments. No two men will agree upon
a perfect result. Human labor merely
approximates a perfect standard and, in
an intricately complicated structure, such
as a power plant, it is practically impos-
sible for any man to completely foresee
the end from the beginning. The owner
has, however, by employing a competent
engineer, insured himself against a fail-
ure of his intentions; he has saved him-
self time, expense and an infinite amount
of trouble; he has secured the best re-
sults obtainable under similar conditions
for an equal outlay.

Many manufacturers of power-plant
equipment place their consulting depart-
ments at the command of anyone who
is in the market for equipment. No
charge is made for this service, the ex-
pense being assigned to the effort to
make a sale. Usually no attempt is
made to displace the consulting engineer,
as the free advice is offered to and ac-
cepted by those who would not ordinarily
employ a consulting engineer.

The results obtained by this arrange-
ment are not, in all cases, entirely sat-
isfactory. Naturally the opinions offered
and the type of equipment advised would
be favorable to the firm giving the ad-
vice. In the case of an open-market
purchase this would work no particular
harm, but it would be manifestly unfair
to other bidders should the job be let
by contract. There is also danger on
the manufacturer's side that, owing to
the extreme eagerness to make a sale,
equipment may be advised, purchased
and installed to do work for which it is
not properly fitted. The result will be
failure and disappointment. Advice which
is valuable is worth paying for.

Modern Tendencies

It is significant of the present trend
of thought among users of power equip-
ment that during recent conventions of
engineers and operating men the papers
presented on this subject have been
mainly from the standpoint of safety,
reliability and permanence of investment;
points which were emphasized in the
ensuing discussions. The terms "effi-
ciency" and "economy," which have or-
dinarily been very loosely used, were
also more sharply defined; and speak-
ers found it necessary to make precise
statements on these points, as interrup-
tions and queries were otherwise certain.

In this connection much interest was
displayed in any account of the changing
over to a new power system or the re-
arrangement of an existing plant to se-
cure better service. Auditors wanted to
know just what steps had been taken
to determine the exact gain to be ex-
pected from the change, what allowance
had been made for expansion and how
the probable useful life of the new ap-
paratus had been determined; whether
it was expected to retain and add to this
as the requirements of the service were
extended, or to discard it, after a certain
lapse of time, in favor of equipment
then developed which would show still
greater economy.

For the most part, the tendency seemed
to be to make plans on the "unit" sys-
tem, with the expectation that power
machinery now being provided will con-
tinue in service for a considerable per-
iod, serving toward the end as a reserve
possibly, but still retaining its usefulness.

It appears to have been felt by many
of those attending conventions that the
limits of engine and turbine steam econ-
omy, except as this may be improved
by further gains in the efficiency of con-
densers and other auxiliary apparatus,
have practically been reached, unless
there are developments now w-holly un-
foreseen. Therefore, equipment installed
during the near future may reasonably
be regarded from the standpoint of
permanent investment and the selection
of the various machines governed accord-
ingly.

How far this theory dovetails with
the facts only the future can determine.
The steam field is not without recent in-
ventions, particularly in Germany, which
may yet revolutionize some features of
power-plant practice

For extensions of economy beyond that
of single machines, the low-pressure
turbine unquestionably offers great op-
portunities; but no power user should al-
low himself to be carried away with
the idea that this provides a certain
means of getting something for nothing.
There are conditions under which it is
a paying proposition and others where it
is not. Hence, the matter ought, in all
cases, to be carefully gone into in ad-
vance.

November 21, 1911

POWER

780

Steam Consiuiiptio/i of Duplex
Pu/iip

What is the steam consumption of a
duplex pump with a steam cylinder of
12 inches diameter; water plunger, 8'..
inches; stroke, 10 inches, when pumping
500 gallons per minute, steam pressure
100 pounds, against a head of 110 feet,
static and friction?

P. S. D.

In first-class condition and working at
a fairly high rate of piston speed, a
duplex pump may develop a horsepower
on 100 pounds of steam per hour; while
with a low piston speed and in an aver-
age state of repair, the water rate may
easily be more than double this.

To pump 500 gallons of water per min-
ute against a total head of 110 feet re-
quires about 14 horsepower.

If the mechanical efficiency of the
pump is 80 per cent., the horsepower de-
livered to the steam cylinder to produce
this will be

14 X 1-25 — 17.5 horsepower
and for an efficiency of 60 per cent, it
will be

14 X 1.66 = 22.33 horsepower
At 100 pounds of steam per horsepower
per hour the steam consumption will be
1750 to 2233 pounds per hour, depend-
ing on the efficiency of the pump.

Receiver Pressure

An engine, 20 and 40 by 42 inches, is
to be started. Assuming that a 24-inch
vacuum will be attained in the con-
denser, and a boiler pressure of 125
pounds, gage, what will be the right re-
ceiver pressure and how is it to be
found ?

F. C. H.

The object of compounding is twofold,
to distribute the load between the cyl-
inder for mechanical considerations and
to reduce the loss from cylinder con-
densation by dividing the temperature
range.

The temperature of 125-pound steam
(140 absolute) is 353 degrees. The tem-
perature corresponding to a 24-inch vac-
uum is 141 degrees. The range is

353—141 212 degrees
If the temperature drop one-half of this,
or 106 degrees, in the high-pressure cyl-
inder, the temperature of the receiver
uill be

3.^3 — 106 : 247 degrees
corresponding to a pressure of 2S.37
Founds absolute, or 13.67 pounds gage.

To divide the loarl equally the re-
ceiver pressure should be 24.5 pounds

absolute. Directions and tables for cal-
culating this were given in Power for
July 18, 1911, page 88. Clearance, wire
drawing and compression would modify
this somewhat.

Carbon Dioxide in l-liie Ciases

.An account of the "High Duty Perform-
ance at the Cincinnati Waterworks"
slates that the flue-gas analyses show
from 10.5 to 11.7 per cent, of carbon
dioxide out of a possible 12.2 per cent.

The statement is something entirely
new to me inasmuch as I always sup-
posed that with perfect combustion the
percentage of carbon dioxide was nearly
2).

Will you give an explanation why it
would be possible to obtain only the 12.2
per cent.?

D. C. G.

Natural gas was the fuel used in the
test of the pumping engines conducted
at Cincinnati and the products of com-
bustion would, of course, be different
from those where coal was used. If
hydrogen gas had been burned under
the boilers, the possible and actual per-
centage of CO would have been zero.

Heating Surface of Corrugated
' Flue

How is the heating surface of a cor-
rugated furnace flue calculated?

W. E. O.

Find the average diameter by adding
together that of the top and the bot-
tom of one corrugation in feet and
dividing the sum by 2. Multiply rhis
by the length of the flue in feet and by
1 <»3. This will give the entire surface in
square feet. That portion of the flue
above the grate will be the heating sur-
face and will be such a proportion of
the whole surface as the portion of the
circumference above the grate is of the
whole circiinifcrcncc.

Air Lift Ca/( u/atioiis
In an air lift to deliver 200 gallons of
water per minute at a hight of 1.30 feci,

what should be the diameter of the water
and air pipes and the air pressure?
J. A. W.

To deliver 200 gallons of water per
minute at a hight of 130 feet above the
surface of the water in the well will
require a 3 -inch pipe submerged 260
feet. The diameter of the pipe should
be uniform throughout its length.

The air pipe should be IJi inches in
diameter with the lower end simply
turned upward inside the lower end of
the water pipe.

It will require about 175 pounds air
pressure per square inch to start to lift
and about 130 pounds pressure for con-
tinuous operation.

Steam Pressure and Temperature

In PovsER for May 16. page 783. under
"Steam and Air Pressure," it is stated
that air at 110 pounds will force steam
back to the boiler and increase its pres-
sure to that of the air. Is it a fact that
steam in the presence of w-ater can be
compressed to a pressure higher than the
temperature of the water from which it
v/as generated?

S. S. H.

Steam may exist at pressures higher
than that due to the temperature of the
confining medium, just as ice may exist
in water warmer than the ice.

Steam is warmer than the cylinder of
the engine it enters and may be com-
pressed in a boiler to a pressure higher
than that due to the temperature of the
water from which it is made.

Authority on Boiler Repairs

Please tell me where I can find de-
scriptions of boiler patching by an un-
disputed authority.

W. R. S.

Patching is a class of repair work on
which there can be no undisputed au-
thority, as conditions vary in every in-
dividual case. Only good mechanical
common sense is of value in this kind
of work.

At the River pumping station the Cin-
cinnati waterworks have four 30.000.000-
gallon pumping engines operating against
a variable head of from 101 to 1,30 feet.
Nut and slack bituminous coal was used
to obtain, in an average duty for nine
months. 120,37fi.000 foot-pounds per 100
pounds of coal, with but two engines
in operation.

790

POWER

November 21, 191 1

Heatin

Heating and Ventilating a
Factory

By John S. Nicholl

In every respect the factory of Brew-
ster & Co., Long Island City, designed
by Stephenson & Wheeler, of New York
City, is an example of modern factory-
building construction. Instead of having
a plain exterior, the appearance of this
six-story structure, surmounted by a
large tower, is not unlike a convention
hall. It is evident that much attention
has been given to the consideration of
the comfort of the occupants. The heat-

an indirect heater suspended from the
basement ceiling immediately below, this
heater being incased in galvanized-iron
ducts that connect to the main-supply
air ducts. For heating the tower and the

reverse, the same description applies to
both.

The fresh-air intakes for the fans are
made of copper capped with a storm-
proof hood and furnished with fine-mesh
copper screens and dampers. Leaving
the fresh-air chamber the air passes
over the tempering coils made up of 2448
square feet of American Radiator Com-
pany's "Vento" radiated surface and
then enters the air wahser. From this
point it is drawn through the reheater of
fil20 square feet of "Vento" radiated
surface and distributed by the fan to
the two main ducts, from whence it is
supplied to the various floors.

Each of the air washers has a capacity
of 85,000 cubic feet per minute. They
are built of galvanized steel braced with
2 and 2 by ui-inch angles. Extending
the full width of the spray chamber is
the spray device made up of brass water
pipe with .Va-inch holes on both sides.
Over this pipe runs a curved copper
hood. The water jets from the spray pipe
impinge on the inside surface of this
hood in such a manner that a double
sheet of water is formed through which
all the air must pass before being de-

1. Plan of Brewster Factory, Showing Heating and Ventilating System

ing and ventilating system includes ar-
rangements for cleansing and humidify-
ing of the air by Webster air washers.

Three systems make up the heating
and ventilating plant, though practically
the entire building is heated by the fan
system. In certain quarters on the sec-
ond and sixth floors, additional radiation
service is secured from a one-pipe sys-
stem. A two-pipe system of domestic
steam supply is provided for certain
domestic steam radiation, including glue
heaters, steam boxes and kettles. The
main-office vestibule is taken care of by

tank house on the roof, there are radiators
.connected with the one-pipe system.

Situated in opposite sides of the base-
ment are two sets of apparatus, making
up the fan system. Each of these sup-
plies to half of the building properly
cleansed and humidified fresh, warm air.
Each group consists of a tempering coil,
air washer, reheater and a fan, driven
by a direct-connected vertical steam en-
gine. Inasmuch as the only difference
in these sets is that one fan is a right-
hand top horizontal and left-hand bot-
tom discharge, while the other is the

livered to the building. Falling into a
tank below, the spray water is recir-
culated by a turbine pump direct-con-
nected to a motor. After leaving the
air washer, the air is drawn over the
reheater and then forced to the various
parts of the building. The inlets of the
fans are 68 inches, the discharge being
horizontal at the top and annular at the
bottom. The 12xl0-inch vertical inclosed
self-oiling steam engine Is capable of
driving them at 250 revolutions per min-
ute. A Powers system of temperature
control is used in connection with thg

November 21, 191!

P O W F. R

791

tempering and reheating stacks. This is
accomplished by a cold-air thermostat
operated at 38 to 40 degrees Fahrenheit
in such a manner as to guard the air
washer against freezing. If the tempera-
ture of the entering air falls below 38
degrees Fahrenheit the tempering coils
receive steam, the thermostat being con-

fan engine is used in the heating sys- the building is heated by recirculated air.
tern and supplemented by live steam An additional advantage of this arrange-
where necessary. ment is that it permits rapid heating of
The flues of the fan system discharge the building during the early morning
in general about 10 fedt above the floor hours by a rapid circulation of the re-

ef the room, and downward at an angle
of about 15 degrees. Screens of plain
lattice or diamond-design mesh are pro-

Exhaus f Heods^ >
ExhaustRis

circulated air.

Vertical Section through Building

nected to the supply and return valve
of the individual groups of the temper-
ing coils. In connection with this system
there is an automatic electric air com-
pressor with a suitable storage tank, au-
tomatic governor, indicating gage, etc.

The tempering stack is made up of
two groups of 60-inch "Vento" cast-
iron radiators, each group being 36 sec-
tions wide and three sections high. The
reheating stack is similar to this, with

vided. Above the register faces are
placed adjustable regulating dampers.

A recirculating flue connection is made
to each intake chamber so that during
the closed-down period of the factory

LETTER

A Homemade Water Heater

In an institution in this country- where
the management could not be persuaded
to install a steam feed-water heater, al-
though a large quantity of water was re-
quired for cooking and bathing, the en-
gineer received permission to get the nec-
essary supplies and install the arrange-
ment shown.

The exhaust pipe from the engine is
5 inches in diameter and exhausts to the
atmosphere. A coil 25 feet long was
connected, as shown, to a 250-gallon
range boiler. The outlet D is connected
to the difterent taps and fixtures in the
kitchens and bath and wash rooms. The
cold-water inlet is located at G. A
jacketed tank heater is connected at B
and C and /I is a drawoff cock.

When the connections were all made
it was found that the fire for the tank
heater could be dispensed with so long
as the engine was running. This meant
a saving in fuel of about one ton per
week. The total cost for material to do
the job was less than $5. Of course, it
must be understood that the range boiler
and tank heater were already installed,
the only cost being for the coil and the
connections to the reservoir.

James E. Noble.

Toronto, Can.

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Fir,. 3. Heater and Tempering Stacks

the exception that it is five groups deep
instead of two. Steam is supplied to
all the systems by three 1.50-horscpower
Heine boilers located in the basement.
The working pressure carried is 1.50
pounds, A reducing valve permits of the
domestic steam system using a pressure
of 30 pounds. The exhaust from the

^ A

Sketch

POWER

November 21, 1911

Westinghouse Marine Reduction Gear

Until recently, there have been but
few attempts to construct gearing for
the transmission of large powers at un-
usually high tooth speeds. The import-
ance of a system of noiseless gearing
to be interposed between a high-speed
turbine and the screw shaft of a vessel
involving the transmission of many thou-
sands of horsepower, has made the at-
tainment of this object an exceedingly
attractive field of investigation.

The most serious problem confronting
the designer of such a system of gearing
has been the development of a mechan-
ism to insure an elastic, uniformly dis-
tributed tooth pressure between gear and
pinion to avoid the concentration of an
excessive tooth pressure at any single
point of the working face, which would
result in rapid deterioration and ultimate
destruction of the teeth.

Fig. I is a perspective view, partly in
section, of the gear perfected by the
Westinghouse company. The illustration
shows one of the gears installed on the
U. S. S. "Neptune." Each gear transmits
approximately 4000 horsepower at a
speed of 1250 revolutions per minute
for the pinion shaft, and about 130 revo-
lutions per minute for the low-speed or
driven shaft. Naturally, double-helical
gears are used on account of the quiet-
running qualities of this type, and the
fact that the opposing helices automatical-
ly balance the end thrust.

The low-speed gear shaft rests in bear-
ings seated in the main casing, and up
to this point the design is fairly con-
ventional.

Hydraulically Supported Frame
The essential and distinctively novel
feature of the design is the hydraulically
supported frame which carries the pinion
shaft and its bearings, and by virtue of
which the pinion shaft is self-alining.

This methpd of suspending the pinion-
bearing frame is said to insure perfect
balancing of tooth pressures, and the
fluid cushion interposed between the
P'nion shaft and the main casing of the
g;ar silences in a large measure the
v.ihe usually associated with the opera-
tion of high-speed toothed gearing. After
a considerable period of operation, the
gear teeth take on an excellent polish
and show no signs of pitting or other
deterioration that usually accompanies
hard and continuous service.

The action of the frame may be more
easily understood by referring to Fig. 2,
which is a diagrammatic section stripped
of all mechanical detail that might be
confusing, and which illustrates the sim-
ple elemental principles of the design.
Fully elaborated detail sections are shown
in Figs. 3 and 4, and the symbols used
in the description refer to the same parts
in all of the illustrations.

Underlying principle oj
design is the supporting oj
the pinion shaft in a frame
7vhich floats on oil, the
pressure on the oil being
automatically regulated icith
the load on the gear.

Use of gear extended to
turbine-driven direct-cur-
rent generators and to cen-
Irijugal pumps.

Referring to Fig. 2, A represents the
frame carrying the bearings of the pinion
shaft, D is a portion of the main casing,
and £ is a right strut or beam secured
to the main casing by means of a series
of steel columns which are shown in
Figs. 1 and 3. It may be noted that A

low cylinders on the lower side of the
frame A, and 2 indicates a similar port
communicating with the corresponding
cylinders on the top side of A.

When the gear is working, the reac-
tion on the pinion teeth will tend to force
the frame A against the casing D or the
beam E, depending on the direction of
rotation. If the reaction on the pinion
teeth tends to force the frame A down-
ward against D, then if oil or other suit-
able fluid under sufficient pressure be
introduced at 1, it will be readily seen
that the frame A will be lifted clear of
the casing, and will actually float on the
fluid in the cylinders. Similarly, if the
direction of rotation be reversed so that
the tendency is to force the frame A
against the beam E, the introduction of
fluid under pressure at 2 will prevent
the frame A from coming in actual metal-
lic contact with E. Since all three cyl-
inders of the set that may be in action
are connected to the same source of
fluid supply, the slightest difference in

FiG. 1. Type of Gear Installed on U. S. S. "Neptune"

does not fit closely between the parallel
faces of D and £, but has freedom for
a slight upward and downward move-
ment.

On the upper and lower surfaces of A
are three circular pads bored out to form
shallow cylinders in which are fitted short
pistons C; 1 indicates a passage or port,
which communicates with the three shal-

tooth pressure on either side of the mid-
dle point of the pinion shaft F will cause
the frame A to yield at the point where
the pressure is unduly high. In thus
yielding, the excess pressure is relieved
and automatically transferred to the point
in the working face of the pinion at
which the tooth pressure was, on the in-
stant, below normal.

November 21. 1911

POWER

793

The broad underlying principle of the
design is, therefore, the supporting of
the pinion shaft in a frame which floats
on oil, and which has no metallic or other
rigid connection to the main casing. The
practical application of this principle in-
volves the accurate and automatic regu-
lation of the fluid pressure in accord-
ance with the load on the gear. The
means by which this is accomplished will

A to the casing D so that the slight ver-
tical motion of the frame is multiplied
at the end of the arm H which controls
the oil valves.

For many years it has been known in
a general way that if oil be fed to a
rotating journal at the point of minimum
pressure, it will be carried by the jour-
nal to the point of maximum pressure,
and if a means of egress is provided the

C DC

Fig. 2. Elemental Sketch of Gear

be understood from a study of the actual
detail sections. Figs. 3 and 4. In Fig. 3
is shown a section through the floating
frame at the middle bearing. The frame
is split in a horizontal plane for con-
venience in removing or inserting the
shaft and bearings. The longitudinal
oil passages 1 and 2 communicate with

oil may be discharged against a pres-
sure substantially equal to the maximum
bearing pressure. Heretofore, practically
nothing has been known regarding the
quantity of oil which might be pumped
through a properly designed bearing.

In the development of this gear, it
was found that b\ suitably proportioning

FtG. 3. Sf:CTK)N THROUGH FLOATING FRAME AT MinOLE BP.ARING

the supporting cylinders, and the duct 6
conveys lubricating oil at low pressure
throughout the length of the pinion frame
and distributes it by means of side out-
lets to the bearings and to the pinions.
An arm R projects into the valve box G
and contains passages communicating
with I and 2. A link H hinges the frame

the bearings and supporting pistons the
former could pump all of the oil re-
quired for floating the pinion frame.

Referring to the section through the
bearing, as shown In Fig. 3. it may be
seen that there are small passages con-
necting the top and bottom of the bear-
ing with the upper and lower cylinders

respectively. The bearings draw in oil
from the lubricating system and dis-
charge it through the check valves /.
into the supporting cylinders, and were
it not for the automatic regulating mech-
anism in the valve box G. they would
build up a pressure considerably greater
than is required to keep the pinion-bear-
ing frame floating in its normal position.
Fig. 4 is a cross-section on a larger

Fig. 4. Enlarged Section through
Valve Box

scale through the valve box G. If the
direction of rotation of the pinion is such
;is to bring the lower set of balancing
cylinders in action, the excess pressure
will tepd to raise the arm B slightly, and
as the ring valve N cannot follow it on
account of coming up against a shoulder,
the surplus oil will escape into the valve
box.

Referring back to Fig. 3, / is a floating
packing which prevents the overflow oil
from spilling directly back into the main
casing and compels it to run off through
the drain pipe K. This pipe discharges
into an open funnel, and the constant
overflow of oil is an unfailing indication

Fic. 5. Showing Method of Lubricat-
ing Gear Teeth

that the gear is functioning properly.
From this funnel the oil may be returned
to the main casing to be circulated again
through the lubricating system.

Oil from Outsidf, Pressure Source

When starting, it may be desirable,
though not absolutely neccs9ar>'. to sup-

794

ply the oil to the supporting cylinders
from an outside-pressure source until
the gear attains the normal speed, and
the pumping action of the bearings is
fully established.

In Fig. 4, oil from such an outside
source of pressure may be introduced at
S and led to the upper and lower valves
as indicated. If the direction of rotation
of the pinion is such as to depress the
frame, the arm D depresses the ring
valve N and the conical valve M, pushing
the latter from its seat. The stem of
the valve M is hollow, as shown in the
section through the upper valve. When
the valve M is opened the oil passes
through the hollow stem, as is clearly
shown, into the lower circular port in B
and thence to the passage 1, Fig. 3,
which connects with the lower set of
cylinders, and is prevented by the check
valves L from escaping into the bearings.
When the balancing pressure has been
attained, B rises to its neutral position,
allowing M to seat and prevent further
entrance of oil. If, by reason of a re-
duction of the load, the oil pressure in
the supporting cylinders becomes exces-

POWER

The connections to the pressure gages
are indicated at 4 and 5, Fig. 4. If re-
cording gages are used instead of sim-
ple indicating gages, and a graphic speed
recorder is connected to the gear, the
charts from these instruments would con-
stitute a continuous log of the power
transmitted.

Location of Pressure Gages
The pressure gages may be located
in any convenient position and as far
away from the gear itself as may be de-
sired. The direction of rotation is al-
ways evident from an observation of
which of the two gages is indicating pres-
sure at the time.

If the gages were placed at any con-
siderable hight above the gear, their in-
dications would have to be corrected for
the hydrostatic head of the oil column
Furthermore, if the gages were located
at a great distance from the gear, there
might be some annoyance from leakage,
solidification or air pockets in the oil
piping. For long-distance indications an
ingenious little device has been worked
out which translates the oil pressure to

November 21. I9i i

In Fig. 1, at the left of the casing is
shown a bracket through the upper end
of which is a screw-adjusted strut bear-
ing agamst the pinion frame. A similar
bracket and strut -not shown in the il-
lustration—are located at the other end
of the casing. These struts are for ad-
justing and maintaining constant thtf
depth of engagement of the gear teeth.
They do not interfere with the movement
of the pinion frame in a vertical plane
To obtain a fle.xible drive between the
turbme and the gear, and at the same
time to keep this gear in close pro.ximity
to the turbine, the pinion shaft is made
hollow, and the driving shaft passes
freely through this bore and is connected
to the pinion shaft at the end furthest
away from the turbine. This is an old
and fairly well known construction which
has been incorporated on account of its
making the apparatus more compact and
not that any novelty is claimed for it.

Adaptability

While the Westinghouse reduction gear
was originally designed for marine pro-

Fic. 6. Gear Used between Turbine
Direct-current Generator

Fir,.

Gear

sive, B rises slightly above its neutral
position, relieving the excess pressure
m exactly the same way as when the oil
is being pumped by the bearings. The
total movement of B for adjusting over
the entire range of load is only a few
thousandths of an inch.

When the direction of rotation is re-
versed, the operation is just the same ex-
cept that the necessary functions are
performed by the upper valves instead of
the lower ones.

From the foregoing description, it may
be readily seen that the oil pressure in
the supporting cylinders is always exact-
ly in proportion to the torque that is be-
ing transmitted. By virtue of this fact, a
snnple pressure gage connected inside
of the valve M will, if the speed in revo-
Uitions per minute be known, indicate the
instantaneous load on the gear, so that
the gear thus arranged is not only an
efficient transmission device but a most
accurate and sensitive dynamometer as
well.

a compressed-air supply, thence to be
conducted to the pressure gages wherever
they may be located. This translating
device is indicated by O, Fig. 3.

Lubrication of Gear Teeth

Fig. 5. a section through the floating
frame and pinion, illustrates the simple
way in which the lubrication of the gear
teeth is accomplished. The frame in-
closes the pinion except for a portion of
the circumference where the teeth engage
with those of the large gear. From the
passage fi, lubricating oil passes to the
pocket in which the pinion is located.
The shape of this pocket is such that
the oil cannot run out, but must be
picked up by the teeth of the pinion. The
oil when picked up is thrown off again
by centrifugal force, but owing to the
construction of the frame, it can escape
only by being discharged directly into
the teeth of the large gears just at the
point of engagement.

Used in Drivlnc, Cemriflcal Plmp

pulsion, in order to harmonize the high
speed which is the essential character-
istic of an efficient steam turbine, with
the comparatively moderate limiting
speed for an efficient propeller, its
adaptability for other purposes is open-
ing up a field even broader than the one
primarily contemplated.

The design of direct-current dynamos
of fairly large capacities to operate at
the high rotative speeds necessar\ for
direct connection to efficient steam tur-
bines has always presented difficulties
that were seemingly unsurmountable.
These difficulties have been eliminated
by interposing the reduction gear between
the turbine and the dynamo, so that each
element of the combination mav operate
at the speed for which it is best adapted
Similarly, centrifugal pumps for lar^e
capacities at moderate heads are not at
all suitrjble for direct turbine drive but
turbine and pump may be connected
through the reduction gear, constituting,
a highly efficient and attractive' unit.

November 21, 1911

POWER

Naturally, for this sort of ser\'ice in
which the direction of rotation is never
reversed, only one set of balancing cyl-
inders and regulating valves is required.

Figs. 6 and 7 illustrate applications to
direct-current generators and centrifugal
pumps. These are only two out of a
large number of new opportunities for
the steam turbine which will present

themselves as soon as it is realized that
the handicap of inherent high rotative
speed can be removed by a thoroughly
reliable and durable system of gearing
having an efficiency of over 98 'i per
cent., and that such a system is now an
accomplished fact.

In addition to the two 4000-horsepower
gears installed on the U. S. S. "Neptune,"

twelve 1000-horsepower and 2000-horse-
power sets have been sold for driving
direct-current generators and for other
purposes. A number of these have al-
ready been in service for some months,
running at speeds as high as 3600 revo-
lutions per minute, with results that are
reported to be gratif\ing in every par-
ticular.

Failure of Scotch Marine Boiler

At 7:30 a.m. on the morning of Octo-
ber 30. a failure occurred in the com-
bustion chamber of a Scotch marine
boiler at the plant of the Mount Clemens
Sugar Company, Mount Clemens, Mich.

The boiler which failed was one of a
battery of eight which were installed in

ber and forced it forward in some places
9 inches. The discharge of steam and
water tore off the tube cap, furnace doors
and the hoppers from the Jones stokers.
These missiles were hurled through a
window, 20 feet in front of the boiler,
and a brick wall on the outside was de-

about 260 pounds per square inch to
strain the stay sheet to its elastic limit
and about 500 pounds per square inch
to strain the staybolts to their elastic
limit. Therefore it seems that the cause
of the failure must have been other than
direct pressure.

'.i, proiuctin
Blown Off

1901 and were used for a period of only
three or four months each year during
the beet-sugar season. It was 1 1 feet in
diameter. 13'< feet long, with triple-
riveted huff joints along the longitudinal
«eam. The shell plate was '.'' inch thick
and the rear combustion-chamber sheet
»5 inch. Supporting the latter sheet were
one hundred and seventy-two I'-i-inch
staybolts pitched 7"ix7"5 inches. The
heads and tube sheets were '^ inch thick.
An inspection after the accident dis-
closed the fact that the staybolts between
the rear head and the rear sheet of the
combustion chamber stripped and the
pressure hurled the latter sheet against
the front part of the combustion cham-

molished. Two men were dangerously
injured from flying debris and a third
who was covering another of the boilers
was so badly scalded that he afterward
died.

The initial failure seems to have oc-
curred at the second horizontal row of
stays from the fop. The position of
the crown bars shows that the rear sheet
of the combustion chamber folded under
the crown sheet. The stayed surfaces
were clean and if is hard to account for
their bulging.

The boiler was connected to a com-
mon main with the other boilers, (he
safety valves being set at 10.^ pounds.
Calculations showed that it would require

Ki AW SuFFT OF Combustion
Chavbfr

POWER

November 21, 191 1

New power flo^se Equipment

The Lanza Continuous Dia-
gram Attachment for Steam
Engine Indicators

In the continuous indicator tlie prob-
lem is to move the paper forward with-
out distorting the diagram. The move-
ment of the paper must be proportional
to that of the piston, and any extraneous
movement is liable to distort the dia-
gram in its outline or area. In some
instruments the drum is given the
additional forward movement while
the pencil is drawing the usually straight
back-pressure line. In another case dia-
grams are taken for alternate revolutions
only, the paper being advanced during
the intervening revolution. Both of these
methods give a series of coirplete dia-
grams overlapping each other.

Prof. Gaetano Lanza, of the Massa-
chusetts Institute of Technology, has
adopted the method of making the paper
move continuously in the same direction,
and always proportionally to the piston
movement.

In the guide extending to the right
in Fig. 1 is a crosshead which is at-
tached to the crosshead of the engine
through a suitable reducing motion, and
with a rigid connection instead of by the
usual cord, as no spring is depended up-
on for the return stroke, and the cross-
head must be pushed back. This elimi-
ates any distortion from cord stretch or
overtravel due to momentum, and gives,
if the reducing motion is correct, a
travel to the miniature crosshead exactly
proportional to that of the crosshead of
the engine. The movement of this minia-
ture crosshead is communicated by
means of the cord attached to it and
running over the pulley at the extreme
right, to clutches below the paper bar-
rel of the instrument, and these are
connected in such a way that the paper
barrel will be revolved always from right
to left, whichever clutch is working upon
it; that is, in whichever direction the
crosshead may be traveling.

The result is the production of dia-
grams like those shown in Figs. 2 and 3.
Fig. 2 represents four revolutions
of a steam engine with varying cut-
off, and Fig. 3 a complete cycle
from a gas engine firing and missing al-
ternately. In the steam-engine diagram
the pencil traces the line A H C, as upon
the ordinar>' card, but the motion of the
paper instead of reversing when the di-
rection of the piston reverses at C, keeps
on in the same direction, drawing the
line C D E, which, being placed below

A B C, as indicated by the dotted line,
would produce the diagram for that revo-
lution as ordinarily taken. Ib the gas-
engine diagram the suction and compres-
sion lines are more distinct when each is
shown by itself than it would be if super-

The atmospheric line is put in by a
separate pencil point, seen in the repro-
duced photograph at the left of 'the
regular pencil. It is adjustable by the
nurled head, projecting above the top
of the paper drum. Still another pencil
point, shown just below that which traces
the diagram, makes the short vertical
marks at R, S, T, etc., which indicate the
end of the stroke. This pencil is brought
into contact with the paper and given
a short vertical motion by the contact
of the small crosshead with the blocks
shown on the upper guide, the position
of which blocks is adjustable by means
of the small gears shown between them.
The paper rolls are arranged so as to

Fig. 1. ViKws of iNtiicATOR, Showing Lanza Continuous Diagram Attachment

imposed, as shown by the dotted lines,
upon one card. The variations of the sev-
eral lines and points of the diagram can
be readily studied, and the mean effective
pressure measured either with an or-
dinary planimeter, or with an elongated
planimeter or integrator by using the at-
mospheric or any other horizontal line
as a base. With the integrator if the
negative areas are traced anti-clockwise,
the reading will be the effective area.
With the ordinary- planimeter, the posi-
tive and negative areas may be measured
separately and their algebraic sum used.

maintain the requisite tension on the
paper, however fast it runs, or however
the relative sizes of the delivering and
receiving spools may vary. The roll is
slipped upon the spindle by lifting the
keeper shown, and as much of the paper
as has been used at any time can be
removed from the receiving spindle, and
the free end of the unused portion
brought around to commence the taking
of another series of diagrams. In the
later model the keeper on the top of
the first spool is replaced by a flat re-
movable plate.

November 21. 1911

POWER

797

NOISS3UdnO0 i

In the large engraving the indicator is
shown as a complete instrument, but the
continuous-diagram apparatus is ordi-
narily made as an attachment to a regu-
lar indicator, in the same way as the re-
ducing motion. This can be clamped
upon any indicator, as shown in the
small panel, without removing the ordi-
nary paper drum or otherwise taking the
instrument apart. It is made by the
Crosby Steam Gage and Valve Com-
pany, 38 Central street. Boston. Mass.

Composition A'alve Disk

A new composition valve disk is being
offered to the trade by the Ohio Injector
Company. Wadsworth, O.

It is dark red in color. The manufac-
turer guarantees that it will not become
brittle and break and that it will last
until worn through. The disk can be
used with most makes of valves using
composition disks.

Duff Ball Bearins Jack

Among the late developments in lifting
jacks is an improved ball-bearing journal
jack recently placed upon the market by
the Duff Manufacturing Company. Pitts-
burg. Penn.

This jack facilitates the rapid and con-
venient lifting of weights and is especial-
ly adapted where a short, light and
powerful jack is required. It is said to
be the only inexpensive ball-bearing jack
providing a positive stop which abso-

Dl'FF BmI -BEARING .IaCK

lutely prevents raising the lifting bar out
of the jack.

An adjustable wheel-holding device has
been designed to hold down the wheel
when operating, but it may be easily de-
tached when not required.

All gears arc forged with machine-cut
teeth and the jack is light In weight and
is easily operated .is the load is raiiied
only on the downward and convenient
stroke of the lever.

POWER

November 21. 1911

Boiler Tube Bursts

On Friday forenoon, November 10,
one man was killed and three injured
when a tube blew out in a boiler in
Ellicott Square, the largest office build-
ing in Buffalo, N. Y. This is reported to
be the third accident of a similar char-
acter that has occurred at this plant
within a week. The first happened on
the Saturday preceding and the second
on Tuesday. In the latter case one man
was slightly scalded. The repair of this
boiler was just being completed when
the tube in another boiler let go. One
of Ihe boilermakers conducting the re-
pairs was killed and the other seriously
scalded. The chief engineer of the plant
and a boiler inspector who were in the
room at the time were slightly injured
by pieces of flying brick.

The boiler had been inspected only a
week before and no defect of a serious
character had been noticed. Further par-
ticulars, if any develop, will be given as
soon as they are available.

Award of Jolin Fritz Medal

At a dinner at the Waldorf-Astoria
closing the annual meeting of the So-
ciety of Naval Architects and Marine En-
gineers, held in New York City on Novem-
ber 16 and 17, Sir ^X'ilIiam H. White, the
British naval constructor, was presented
with the John Fritz medal for 1911. The
presentation speech was made by Onward
Bates, of the American Society of Civil
Engineers. The medal was awarded Sir
William for notable achievements in the
field of naval architecture.

News from the Institute

Colonel Goethals branch (Yazoo City,
Alias.), of the Institute of Operating En-
gineers, started its regular bimonthly
meetings the last part of September. The
following papers were read at the meet-
ing on October 14: "Safety Valve Cal-
culations," by J. Chisholm, junior ap-
prentice; "Safe Working Pressure of
Boilers," by F. C. Holly, master operat-
ing engineer; "Boiler Horsepower," by
W. G. Richardson, master operating en-
gineer. In this branch it has been de-
cided to conduct a full course in which
papers will be presented covering the
subject "The Boiler Room and Its Special
Attachments," and all the problems con-
nected therewith that an operating engi-
n."er should know. At each meeting the
members are given a subject for discus-
sion at the ne.\t meeting.

The New York branch held a meeting
on October 20 and voted to name the
branch after J. C. Jurgensen, the founder
of the institute. In this branch it has
been decided to give a course of lectures
during the winter on power-plant ac-
counting.

- The new educational bulletin is now
ready for distribution. It will give the
announcement of special rates secured

from the correspondence schools for stu-
dents who wish to take up the institute
work by the correspondence method.

Isometric Drawing Paper

From the Norman W. Henley Publish-
ing Company, 132 Nassau street. New
York City, we have received a pad of
isometric drawing paper, for the special
use of engineers.

It is claimed for this paper that any
knowledge of isometric projection is un-
necessary, as its isometric ruling makes
it easy to complete such a drawing with-
out arduous study or calculation; any
branch of mechanical drawing can use
the paper to advantage.

The paper could be profitably em-
ployed by engineers who contribute to
the technical papers and wish to illus-
trate their articles by drawings but are
not equipped with all the necessary draw-
ing implements. The lines are so ruled
that but little difficulty will be had in
plotting the figure desired.

OBITUARY

Henry W. Bulkley, the inventor of the
first practical injector condenser, died on
November 8 at his home in East Orange,
N. J., of heart disease. Although 70 years

Henry W. Bulkley

of age, Mr. Bulkley always enjoyed good
health until a week before his death.

Born in New York, in 1841, he re-
ceived a common-school education and
took a scientific course at the City Col-
lege. When the Civil War broke out he
enlisted in the Navy and served as a
junior lieutenant in the engineering corps
during the latter part of the war.

Mr. Bulkley started in the manufactur-
ing line in the late sixties and in a few
years invented his well known injector
condenser. He continued the manufac-
ture of the condenser up to the time of
his death.

He was a member of the American So-
ciety of Mechanical Engineers, American
Society of Mining Engineers and the
American Society of Electrical Engineers.

Mr. Bulkley is survived by a son, Henry
D. Bulkley, who will carry on the busi-
ness as formerly.

PERSONAL

O. D. Hogue has been appointed vice-
president and treasurer of the Goulds
Manufacturing Company, of Illinois.

W. H. Peterson, Ponland, Ore., has

been appointed chief engineer for the

Court House building, Portland, by the
board of countv commissioners.

Charles E. Hague has been appoint-
ed Philadelphia representative of the
Best Manufacturing Company, of Pitts-
burg, with headquarters at 1510 Land
Title building. He is to have charge of
ihe eastern Pennsylvania, Baltimore and
Washington territory.

C. L. Stickney & Co. have been ap-
pointed the representatives of the Best
company in the States of Washington
and Oregon, with headquarters at 108
NX'liite building. Seattle, Wash.

SOCIETY NOTES

The Eighth International Congress of
.Applied Chemistry has invited the Ameri-
can Society of Refrigerating Engineers
to take part in its proceedings on Septem-
ber 4, 1912, at Washington, D. C. The
congress is to be held under the patron-
age of the President of the United States.

Partial announcement has been made
of the program to be carried out at
the annual meeting of the National Gas
and Gasoline Engine Trades' Association,
at the Hotel Hollenden, Cleveland, O.,
December 5 to 8 inclusive. The morn-
ings of each day will be devoted to the
exhibitors, as at previous conventions
both exhibitors and engine manufactur-
ers complained that not enough time was
allowed for inspection of the accessories
shown. Wednesday, the sixth, has been
set aside as "engine manufacturers' day."
This meeting will probably commence
about 10 a.m., holding a session then
and another in the afternoon. Aside from
this there will be no programs for the
mornings of any day, leaving these free
for the inspection of such accessories
as may be displayed. Tuesday afternoon
will open the convention program, in the
usual form, followed by reports of of-
ficers, announcements of committees,
etc. Tuesday evening there will be an
open meeting for power users under
the auspices of the Cleveland Chamber
of Commerce. Wednesday will be man-
ufacturers' day. Thursday afternoon
there will be a program of papers, as
also on Friday afternoon. TTiis being an
annual meeting, there will be an election
of three members of the executive com-
mittee on Wednesday evening, followed
by the annual meeting of the executive
committee on Thursday noon, for the
selection of officers.

NKW ^()RK. N()\ TAIUKR 2X, 1M|1

N.I

o

W

1 n

t h

J () b—

H

ONESTLY, between ourselves,
if you were managing a power
plant where the engine room
was a source of pride to
you as its chief; where
the equipment was not
only highly efficient but
looked it — and

You advertised for an
engineer — and

* You lined up eight or

ten applicants — and

You ran your eye (ner the line —

What Woum) Be Y'»uk First
Imprfcssiox'

Why, the type of engineer pictured
above would look, good to you when
contrasted with the careless-looking
man in the next column — you'd think
his appearance an index of his proliable
carelessness in the engine room.

The first impression has many times
turned away the better of two good en-
gineers.

No man need be a tailor's dummy
to be neatly and plainly dressed.

No man need look like an animated
hunk of oily waste; running a steam
plant is often dirty work, but it earns
clean money.

Because a man has to clean boiler
tubes once a month he need not go
about looking like a chimney sweep.

Clean overalls stay clean in a clean
engine room.

Behold the salesman in all his glory!
Would he ever get by the office boy if
his appearance did not typify the pro-
duct he is trying to sell?

No! He looks the part. He looks
like good goods. He is the goods at
the startoff!

The ethics ot good
engineering business
contains this clause:

Be clean; be neat;
look just as bright and
snappy outwardly as
your mentality is in-
wardly.

Y c) u Must Look the Part!

POWER

November 28, 1911

City Sewage Flushing Plant

There has recently been put into op-
eration a novel method of pumping sew-
age water by the city of New Yorl<. This
plant is located at the foot of Douglas
street, Brooklyn, and is used to flush the
Gowanus canal. Originally the condition
of the water in the canal was not bad,
but the increased population and manu-
facturing industries have made this water
at present most foul.

At one time it was supposed that the
tide would clear the canal of all im-
purities, and storm water sewers were
run into the head of the canal through
which a large amount of surface water
was drained from the streets of the city

By Warren O. Rogers

An ordinary marine pro-
peller is used for sewage-
flushing purposes.

The propeller is driven
by a 4.00-horsepower induc-
tion motor, and has a cap-
acity of 500 cubic feet of
water per minute. The
plant is operated by the
city of New York.

- A steel circular motor pit has been
built 24 feet deep and 29 feet in diam-
eter. The plates are 'i inch at the top
and i4 inch in thickness at the bottom
and are set on a concrete foundation 5
feet thick. This concrete foundation
rests on sheet-steel piling which reaches
down to a depth of 10 feet.

In this motor pit is a 400-horsepower
induction motor which receives three-
phase alternating current at 550 volts; it
is shown in Fig. 2. The motor runs at
120 revolutions per minute, full load,
and is connected by means of an 8-inch
shaft to a 9-foot propeller, which has
four adjustable blades with a pitch of
5 feet 6 inches. The shaft runs through
a water-cooled thrust bearing placed be-
tween the motor and the stuffing box in
the partition between the motor pit and
the wheel pit. The shaft is supported in
the tunnel by two lignum-vits bear-
ings. The tunnel has an opening 50 feet
wide at the canal and is 12 feet deep,
but it narrows down to 9 feet at the
wheel, allowing for J-s-inch clearance,
and then diverges to 12 feet in diameter
beyond the propeller. The propeller is
56' J feet distant from the motor. It
has a capacity of 30,000 cubic feet
per minute. The water is delivered
into Buttermilk channel through a
sewer 6300 feet long. The water
handled by this propeller weighs ap-
proximately 64 pounds per cubic foot.
The motor is reversible, so that in case
the propeller becomes fouled it can be
reversed and made to free itself. The
blades are also reversible, and the flow
of water can be reversed should it ever
become necessary.

The speed of the motor is controlled
by a drum-type, rheostatic hand con-

FiG. 1. Gowanus Canal and New City
Pumping Plant

of Brooklyn. But this arrangement failed
to come up to the expectation of those
■who advanced this idea. As far back as
1880, the city engineers were engaged in
solving the problem of bettering the
■unsanitary conditions of the canal.

During recent years the condition of
the water has been so filthy and foul,
and a demand for a final solution so
great, that the city engineers finally de-
vised a plan for doing the work by flush-
ing the water from the dead end of the
canal into the East river, where it will
be swept away by the tides.

In Fig. 1 is shown an exterior view of
the pumping plant. The building is set
back from the street, covers a plot 67x63
feet and is fronted by a green lawn and
gatehouse. The building is constructed
of red brick with a concrete floor, with
green glazed brick around the lower por-
tion of the wall for the inside.

loLiK HUNllKKD-HOKStPOW KK IiMHiCTION AiOTOR IN MOTOR PiT

November 28, 1911

P O V!' E R

801

troller placed beside the motor in the
motor pit.

The tunnel on each side of the pro-
peller is provided with two 14-foot gate
valves which are motor-operated and are
raised and lowered by means of ver-

uses on all of the motors. There is also
a main switchboard on which are mounted
the power-factor meters, the frequency
meters, two ammeters, two voltmeters
and one recording wattmeter. There is
also a separate switchboard for operat-

FiG. 4. Main Floor of the Pumping Plant

tical screw stems. These gates permit
emptying the tunnel section between
them if it becomes necessary to get at
the propeller wheel. To do this a sep-
arate motor-driven pump is used to pump
out the sump into which the water in
this section of the tunnel is emptied. A
plan of the flushing arrangement is shown
in Fig. 3.

On the main floor of the building are
located three oil-cooled transformers
(Fig. 4), which transform the electrical
energy from 6600 to 550 volts for

ing the 10' .-horsepower m.ctors which
operate the gates, and one for controlling
the vertical centrifugal 12-horsepower
pump motor which is connected to the
sump. As in most other of the city plants,
Edison current is used, and there are
two switchboards for controlling the in-
coming electrical energy, one for the
central station, the other for the plant.

This flushing plant was first operated on
.June 9, for three hours. Beginning June
21, the plant was run for 108 hours and
obser\'ations indicated that the propeller

could be relied upon to change the
water content of the entire length of the
canal in eight hours. With the wheel
working at its normal speed, a current
toward the head of the canal of 4 inches
per second was created at a point one
mile away from the intake. The channel
bed, however, is so foul from the ac-
cumulated wastes of many years that it
will probably take several months' pump-
ing before conditions reach a satisfactory'
state.

The work of designing and building
the Gowanus flushing tunnel and pump-
ing plant has been carried out by the
bureau of sewers of the borough of
Brooklyn, under the direction of E. J.
Fort, chief engineer.

Pliilippine Coal for Home
Use

The Philippine Islands are commencing
to produce a considerable portion of their
own coal supply, according to United
States Consul-General G. E. Anderson,
at Hongkong.

.At East Batan the mine is turning out
100 tons daily and when its new chute
system is completed it is expected that
100,000 tons a year will be the output.

Over 400,000 tons were imported in the
fiscal year ending June 30, 1911. Up to
1909, Australia supplied most of the
coal used, but during the last two years,
owing to labor troubles in the former
country', Japan has furnished nearly one-
half of the total imports.

Aided by the government of the
Philippines in its advancing funds against
contracts for coal, it is believed that
the entire local output will be taken by
the government or by local consumers,
for the next year or more, and there will
be no necessity of importing coal.

Fic. 3. Plan of thf FtrsHiNr. Tunmel and Proph lfr Conni:ction

802

POWER

November 28. 1911

The Fusing Temperature of Coal Ash

Factors Govkrning Rate of Combustion

The rate of combustion depends pri-
marily upon the rate of air supply to
the heated surface of the fuel in the
furnace. The difference in draft pres-
sure across the fuel bed is generally con-
sidered to be a measure of the rate of
combustion. This, however, is true only
when other conditions, such as the re-
sistance of the fuel bed to the Pow of
air, surface of fuel exposed, etc., are
the same. Any difference in the condi-
tion of the fuel bed, such as its thick-
ness, closeness with which it packs or
cokes together, the accumulation of ash
or the formation of clinker, will cause a
change in its resistance by changing the
length of the restricted passages through
it or by reducing the available area for
the flo-v of air and thereby affecting its
flow for any given drop in draft pressure
across it. Sometimes a thin vitreous
clinker will form over the entire grate so
that no air can pass through the fuel
bed, and combustion ceases, even though
there may be a difference of a half inch
or more of draft between the ashpit and
the furnace.

The thickness and condition of the fuel
bed govern the area of fuel exposed
to the air passing through it and thereby
affect the rate of combustion as well
as the relative excess or deficiency of
air supply.

All coal contains more or less ash,
some of which was in the original vege-
table matter from which the coal was
formed; other ash resulted from the de-
posit of mud or silt in the water in which
this vegetable matter was submerged,
while a third source is from the water
which filters through the coal seams as
it passes from the surface to the sub-
terranean streams and springs. This
water is charged with lime, iron, etc.,
some of which is retained in the coal
seams and appears as ash when the coal
is burned. Ash usually contains alumina,
silica, lime, magnesia, soda, potash, iron,
phosphorus and sulphur, but the relative
amounts of each vary widely in different
coals. In general, the ash resembles
clay, but it varies more in its composition
and characteristics than do the clays used
in making red building brick as compared
with that used in making good firebrick.

The ash from different coals varies
widely in its fusing temperature, some
melting at a temperature as low as 2000
degrees Fahrenheit while other ash re-
quires more than 3000 degrees Fahren-
heit to fuse it. Clinker is nothing but
incited ash, and ash having a low fusing
temperature will form clinker much more
readily than will an ash of a high fusing
temperature when subjected to the same
fuel-bed conditions.

Seldom all the ash, even though having
a low fusing temperature, is melted into

By E. G. Bailey

The main factor in the
formation of clinker is the
difference between the fus-
ing temperature of the ash
and the temperature to
which it is subjected.

Any factor, such as ex-
cess air, rate of combustion
and thickness of fuel bed,
which will affect tins tem-
perature, may cause a cor-
responding change in the
amount and nature of the
clinker from any given coal.

*I!«i(l lietiin- II, e (ilii.. Sociptv of Mechan-
ical, Kli^ctrii'al and Stoam Kn^'ineois, at Can-
ton, November IT-lN.

a clinker in a boiler furnace. One rea-
son for this is that all parts of the fuel
bed are not hot enough to melt the ash.
Another reason is that the composition
of the ash in different parts of the seam,
and therefore in different lumps of coal,
may vary so that some of it melts readily
while the other has a fusing temperature
well above that of the fuel bed. In actual
tests it has been found that the percent-
age of ash which is formed into clinker
as well as the obstructed grate area per
pound of clinker holds a close relation
to the fusing temperature, of the ash
from different coals when burned under
similar conditions.

Formation of Clinker Dependent
upon Fusing Te.mperature of Ash

If there is a variation in the condi-
tions, such as fuel-bed temperature,
method of handling the ash, etc., dif-
ferent amounts of clinker will be formed
from the same coal. The real measure
of clinker formation is the difference be-
tween the fusing temperature of the ash
and the temperature to which this ash is
subjected. If an ash which melts at 2100
degrees is subjected to an actual tem-
perature of 2500 degrees, the ash will
not only be melted, but it will become
very fluid and contain a considerable
quantity of heat above its solidifying
temperature and, like overheated iron,
will run quite a di^ance against the in-
coming cold air before it hardens into a
clinker. Under these conditions it is
likely to form a very thin clinker and
obstruct a considerable portion of grate
area. On the other hand, if ash requir-
ing 2450 degrees to fuse it is subjected
to this temperature of 2500 degrees,

some clinker will be formed, but it will
be a smaller proportion of the total ash
and will be of the open, porous kind
which quickly cools as it gets into a
cooler zone; it will also have less detri-
mental effect in obstructing the passage
for air and reducing the rate of com-
bustion.

It is well known that a fireman who
bars and stirs his fire so as to lift the
ash up into the fuel bed, is only aug-
menting the formation of clinkers, and
he is doing just what he should not do;
that is, subjecting the ash to the hottest
part of the fuel bed instead of leaving
it as near the grates as possible, where it
wmII keep cool until it can be worked
through the grates into the pit or until
the fire is cleaned. The admission of
steam under the grates or merely the
presence of water in the ashpit has a
cooling tendency upon the lower part of
the fuel bed, and thereby reduces clinker
trouble.

Results of Tests

Two 24-hour boiler tests made on three
vertical fire-tube boilers for the purpose
of determining the relative commercial
value of two similar coals, show some
very interesting data regarding the rela-
tion between the fusing temperature of
ash, clinkers, rate of combustion and
boiler efficiency. All conditions were
maintained as nearly the same as pos-
sible on the two tests, and great care
was taken in regard to the weights of coal
and water, coal and ash samples, flue-
gas analyses, draft readings, etc.

The data bearing upon clinkers and
rate of combustion are given in Table 1.
The ash and heat value of the two coals
were practically identical on the dn,-
basis, and while there was a slight differ-
ence in the character of the two coals as
indicated by the volatile matter, the prin-
cipal difference was in the fusing tem-
perature of the ash. this being 2750 de-
grees Fahrenheit for A and 2390 for B.
The same two firemen fired during both
tests, and they were equally familiar with
the two coals.

On test No. 1 with coal A, all fires
had been cleaned three hours before
starting the run, and no further cleaning
was done except during the twenty-first
and twenty-second hours of the test,
when all the fires were cleaned. The
fire was sliced six times during the test
and no clinkers were taken out except
when cleaning.

On test No. 2. with coal B. consider-
able trouble was encountered on account
of the formation of clinkers. The fires
were sliced 1 1 times, and even though
all the fires had been cleaned three hours
before the beginning of the test, it be-
came necessary to pull out some clink-
ers during the sixth, twelfth and eigh-

November 28, 1911

POWER

803

teenth hours of the test, and all fires
were thoroughly cleaned during the
twentieth and twenty-first hours of the
test. There was difficulty at times in
maintaining the desired steam pressure,
which on the average was 5 pounds lower
than with coal A. The draft for coal A
was 0.22 inch, while for coal B it was
0.26 inch, and about 4 per cent. less
horsepower was developed.

T.\BLE 1. UESULT.S OF TWO
24-norU TESTS

Number of boilers S

Type of boilers Vertical fire tube

Total grate surface, square

feet , MO

Hight of furnaces, inches. 3S.5

\Vater-heat ing surface,

square feet 3367

Superheatine surface,

sijuare feet 1347

Type of grates stationary

.■\ir space in grates, per

cent J. . .in

^Villth of air space, iuch. . i

Test number 1 2

Duration of ti-st, hours. . . 21 24

Steam pressure by gage,

pounils 102.0 07.2

IJraft between damper and

boilers, inches of water. 0.22 0.26

])raft in firetjoxes, inches

of water 0.14 0.16

Temperature of flue gases,

leaving boiler, degrees

Fahrenheit .">7 f .'.Si

Coal u.sed .4 B

Sixe of coal nin-of-niine

Analysis of coal:

Moisture, iier cent 2.74 4.11

Volatile, per cent 10.06 21. S2

Fixed carlKin. percent.. 74.50 .68.-38

Ash, percent 5.80 5.69

Sulphur, per cent 0.71 1.27

I>ry ba,sis.ash 5.96 5.93

Dry basis, H.t.u 14,.S02 14,S06

Fusing temperature of
ash, degrees Fahren-
heit 2,750 2,390

Veight of coal burned,

pounils 24,974 24,603

\\ eight of ash and refuse

from grate, pound.s 804 1365

Weight of asb and refuse

from pit. pounds 1101 824

Total w.iu'ht of ash and

r>-fu3e, pounds 1905 2189

Total weight of clinker,

hand-pickiil from grate

refuse, imunds 294 746

IVreent.ige of aith and ref-
use to coal 7.03 8.90

1'iTtenI.ige of clinker to

eoal burned I. IS 3.03

I'errentage of Clinker to

a^h in <T>al burni-d 20.2 53.3

I'rojeoted area per pound

<if rlinker. -ipiare fwl . 0.076 O.lOtf

t'aleulalefl total grate area

obstriieled by clinker,

sipiare f.-et 22 79

IV-rn-ntage of combitstible

in total refuse 21.31 .35

<'<jal biirne*! jier sniiare

foot of grate jier hour,

IMiiinfN 12.5 12.4

Iloiler hor*e|»ower devel-

oixhI 279.4 268 1

I'eref'nlage of rat***! hor<e-

imwer develo|K-<l 90.2 86.5

Flue ga" anaiv~H:

Carbondioxide.pj-rcent. 10.73 lO.O.'i

(>xvK-n. p,.r eeni 8.12 8. 07

Carbon moiioxiile,|H'rcl. 1.08 0.88

.Nitrogen, p'T cent .... 80,02 80.10

Air •xci-ss, per cent. .. . 63.5 76.0

Ileal tinlance;

Ileal iisetl In evapora-
tion. IKT wnt . 62 4 61 7

1/xs line to latent heit 2 9 2 8

Ixwt flue to iiroflud." of
combu«tion Id s 10 2

lx>-s due to air «^o«». . 6 0 6 6

Ixws due to CO j.l 4 3

]jo>*^ due to oombiLiitiblc

in refiw 19 3 1

Ixws due to rv illation
anrj iinarmiintf^d for
(difference) 10 9 11 3

liKl.n 100 o

All of the difference between the action
of the two coals is traceable directly to
the formation of clinkers. With coal A
804 pounds of refuse were cleaned from
the grate, a large portion of which was
slate and such impurities, and 1101

pounds were taken from the pit. With
coal B the conditions were nearly re-
versed, 1365 pounds being taken from
the grate and 824 pounds from the pit.
All clinker larger than about 1 inch was
picked out of the refuse from off the
grate and weighed. This amounted to
294 pounds for coal A and 746 for coal B.
However, in both cases considerable
clinker had been broken into small pieces
during the cleaning and handling so that
these results do not represent the total
weight of ash which was fused to a
clinker, but the results are comparable.
The clinker picked out was 20.2 per cent.

1

1 ■;

30,000

^ c

2

o

P 20,000

! -- .CooTf^""^"-^

[■ •

.

10,000

1

"^J-i

1 .¥

^

1 hejifd

n

1 V

s

V 1 1

8 10 12 W 16 » 20 ez 24'
Holts of Test

Fig. 1. Effect of Clinker Formation
Upon Evaporation with Coals A and B

of the weigh* of ash contained in the
amount of coal A which was burned, and
53.3 per cent, of the ash in coal B.

Still further data were obtained rela-
tive to the thickness and area obstructed
by the different clinkers. A large num-
ber of clinkers of various sizes were
laid on paper and the projected outline
of each was drawn. From these areas
and the weight of each individual clinker,
the projected area per pound of clinker
was determined, and was found to be
0.076 square foot in the case of coal A,

2000

1500

o|ip 1000

500

to... " 123456789 10
Hours of Test

Fir,. 2. Results with Different Coals
AT Ohio State University

and 0.106 square foot for coal B. This
means that the clinker from coal B was
so much thinner that the same weight
would obstruct about one-third more
grate area than that from coal A. Multi-
plying these values by the weight of
clinkers from the respective coals gives
respectively 22 and 79 square feet of
obstructed area if all of the clinker were
on the grate at the end of 24 hours. The
clinker, however, is ffccumulalivc and the
effect of it can best be studied by re-
ferring to Fig. I, which is plotted from
Table 2. In this table the factor com-
puted by dividing the weight of water
fed to the boilers each hour by the
square root of the average draft for the
same period, is equivalent to the weight

">N^ 1 1 1 ' 1

:j^

>C6o^M-

±TL

^>£2aiV^

L_]_

1 s^~

-

Oooip ^ -^

^opT^

j j

1 1

cf water evaporated per hour with 1 inch
of draft, assuming that the rate of evap-
oration varies as the square root of the
draft for any given fuel-bed condition.
From the plotted results of coal A. it
is seen that the rate of evaporation per
unit draft is substantially uniform
throughout the test. In other words, the
accumulation of refuse on the grate
causes so slight an increase in the fuel-
bed resistance as compared with the re-
sistance of the fuel bed itself that prac-
tically no more draft was required at the
end of a 24-hour run than at the begin-
ning. On the other hand, coal B shows

i2 3200
J 3100
g>3000

1

1 1

1

< 2800

5 2600
o 2500

\

^

\l>

' > !

Vi^ 1 ' 1

Vs.!^"

^ 2300
O12200
■» 2100
•^ ?rtm

v^-

^.,

V

^^

--

20

30

40

50

€0

Perc«ntogeof Ash Fused into Clinker

Fic. 3. Results with Different Fur-
naces

a decided decrease in the rate of evap-
oration per unit draft as the clinker ac-
cumulates. The effect of taking out some
clinkers during the sixth, twelfth and
eighteenth hours is noticed by the in-
creased rate of evaporation per unit draft.
The effect of the thorough cleaning near
the end of each test is apparent in caus-
ing a reduction in the rate of combustion
while the fires arc being burned down,
cleaned and brought back into condition.

Conclusions
The conclusions to be drawn from
these tests are that more clinker of a
much more troublesome nature results
from the coal with the ash of lower fus-
ing temperature, and if a limited draft is
available so that all of it is required to
evaporate the desired amount of water
when thV grates are clean, coal A would
carry the load satisfactorily when clean-
ing the fires only once in 24 hours, while
coal B under the same conditions drops
off 25 per cent, in the evaporation in IS
hours, even though two partL-^l cleanings
have been made in the meantime. Hence
the plant with limited draft must give
due consideration to the clinkering prop-
erties of the coal used.

Tests at Ohio State Univkrsity
Table 3 gives data from several boiler
tests made by Professor Hitchcock at
Ohio State University. Most of these
tests were of 10 hours' duration, start-
ing with a fire which had been cleaned
one hour before the beginning of the test
and again during the forepart of the
tenth hour of the test. In the cases of

804

POWER

November 28, 1911

coals C and D, the draft used in cal-
culating the factors was that measured
between the boiler and the damper, while
the firebox draft was used in the others.
Coals C and D were burned on a plain
grate with 50 per cent, air space under a
dutch oven, while coals £ and F were
burned on shaking grates under a fire-
brick arch with a special horizontal re-
turn-tubular boiler setting.

When burning coal C there was a de-
crease of about 20 per cent, in the rate
of combustion during each of the second
and third three-hour periods as compared
with the one preceding, which was due to
the formation of a thin, vitreous clinker.

Coal D showed considerable variation
in the rate of combustion per unit draft
in the different periods of the various
tests. This may be due in part to the
peculiar coking action of this coal which
caused it to vary greatly in the resist-
ance of the fuel bed itself. The average,

same as coal E. Comparing the second
test of coal F with the first, it is noted
that the average rate of combustion was
nearly twice as much, the percentage of
ash fused to clinker was more than
doubled, while the rate of combustion
decreased nearly three times as fast as
on the first test with this coal. The
clinker formed from this coal covered
0.13 square foot of grate per pound of
clinker.

The relative rates of combustion dur-
ing the three periods of the tests of coals
C, D, E and F are plotted in Fig. 2.

From a careful study of the various
individual tests of Table 3, it is noted
that there is an indication that the per-
centage of ash fused to clinker increases
with a decrease in the air excess, which
means an increase in the fuel-bed tem-
perature. Also from the tests of coal C
there appears to be a decrease in the
percentage of ash fused to clinker as the

Results with Different Furnaces

As a further evidence of the relation
between the fusing temperature of ash
and the formation of clinker, reference
is made to Fig. 3, in which are plotted
the results of several tests on different
furnaces, several coals of various fusing
temperatures being tested in each fur-
nace. In these tests, like those previous-
ly described, all clinker larger than about
1 inch was picked out of the refuse and
its percentage to the total ash in the coal
burned was determined. The general con-
ditions prevailing in these furnaces dur-
ing the tests were as follows:

Furnace H K

.\verage coal burned per square

foot of grate per hour, pounds. .22 11
.Average draft in firebox, inches of

water 0. 12 0 39

Average air excess, per cent SO 133

The conditions in furnace H during
these tests were more as they should be,
while furnace K had a much stronger

TABLE 2. SHOWING EFFECT OF ACCUMULATIVE CLINKER

Test

No. 1. (GAL A

Test No. 2

Coal B

Percentage of

Percentage of

Draft in Flue

Time Damper

Draft in Flue

Time Damper

Water Fed to

b.v Recorder,

Was Wide

Water Fed to

hv Recorder,

Was Wide

Hour of Test

Boilers, Pounds

Inches

Open

\/ Draft

Boilers, Pounds

Inches

Open

V Draft

1

7,730

0.07

0

29,200

11,995

0.28

100

22.600

2

8,808

0.10

0

27,800

8,868

0.26

100

17,500

3

8.109

0.15

0

21,000

10,075

0.28

89

18,900

4

8,468

0 17

0

20,600

10,853

0.28

79

20,200

5

9.220

0 29

53

18,500

10,382

0.29

99

19,200

6

8,299

0.19

13

19,000

6,518

0.08

4

19,400

7

9.102

0 18

0

21,200

7,346

0.29

91

13,700

8

9.749

0 23

76

20,400

9.951

0.28

100

18,600

9

8.566

0 22

44

18,300

10,669

0.29

100

19,700

10

10,768

0.30

100

19,700

10.853

0.28

91

20,500

U

12,016

0 29

79

22,300

10,578

0.29

100

19,600

12

12,368

0,30

90

22,400

9,207

0.28

100

17,300

13

10,878

0.29

94

20,200

8,881

0.37

100

14,700

14

10,500

0 25

58

21,000

8,737

0.30

100

16,000

15

5,965

0.14

13

16,000

9,077

0 30

100

16,600

16

9,991

0.24

75

20,400

. 8.306

0.30

100

15,200

11,067

0.24

68

22,500

8.437

0 29

79

15,500

18

9,834

0.22

56

21,000

7,953

0.28

89

15,100

9,677

0.22

60

20,600

8,813

0.25

58

17,600

20

10,114

0.23

73

21,100

8,533

0.22

0

18,200

0.23

63

13,700

4,033

0.17

0

9,800

6,207

0.24

33

12,700

5,9.58

0.20

4

13,400

23

4.966

0.17

28

12,000

8.378

0.23

19

17.500

Average

10,369

0.23

58

21,600

6,223

CIS

0

14,700

9,139

0.216

47

20,100

8,735

0.261

71

17.100

however, shows practically the same rate
of combustion during each of the three
periods. This coal formed a fragile,
porous clinker which evidently offered
very little additional resistance to the
flow of air through the fuel bed.

With coal E a thin clinker which ob-
structed about 0.21 square foot per pound
was formed and had a decided influence
in decreasing the rate of combustion. The
difference between the second and third
periods was not so great as between the
first and second. This may have been
due to the greater use of the shaking
grates during the latter part of the tests.

Coal F had a higher ash-fusing tem-
perature than coal E, yet there was near-
ly three times as much ash in the same
weight of coal, and, being a free-burning
noncoking coal, it burned at a higher rate
with the same draft and therefore so
formed clinker that the rate of combus-
tion during the third period was 75 per
cent, of that during the first, or about the

intensity of the draft is increased. It is
plausible that the stronger draft and the
higher velocity of air causes the lower
part of the fuel bed to be enough cooler
to prevent the formation of so much
clinker, although it has previously been
assumed that the higher the rate of com-
bustion the higher the furnace tempera-
ture and therefore the greater the amount
of clinker formed.

The fact that the different conditions
under which the same coal may be
burned will cause different percentages
of its heating value to be utilized in evap-
orating water, does not argue against
the B.t.u. being considered in the pur-
chase of coal, nor 3oes the variation in
the factors affecting the formation of
clinker interfere with the fusing tempera-
ture of the ash being used in connection
with the purchase of coal, so that some
certainty and uniformity may be assured
in the all-important factor of its clinker-
ing property.

draft than was needed and the excess
air was correspondingly high. On ac-
count of the higher rate of combustion
and the lower excess air, furnace H was
much hotter than furnace K and as a re-
sult of this, more clinker was made from
ash of the same fusing temperature than
in furnace K.

One of the most striking points brought
out by these curves is that the percent-
age of ash fused to clinker increases
very rapidly as the fusing temperature
of the ash falls below 2500 degrees Fah-
renheit. Another imponant factor is
that with a lower fusing temperature of
the ash the character of the clinker
changes, so that much more grate sur-
face is covered per pound of clinker.

Formation of Clinkers with Mechan-
ical Stokers

In the case of mechanical stokers the
clinker trouble varies with the type of
stoker. Some make more clinker from

November 28. 1911

POWER

805

the same coal than would be formed in
a hand-fired furnace, while in others the
ash is continually being taken from the
furnace before troublesome clinkers are
formed. Ash of a very low fusing tem-

greater part of the sulphur bums and
leaves the furnace in the form of a gas.
From 3.!i the data accumulated so far,
there appears to be no relation whatever
between the sulphur in the coal and the

amount or nature of clinker formed, nor
is there any relation between the sul-
phur and the fusing temperature of the
ash.

Many users of gas coal have deter-

T.A.BLE 3. RESULTS OF

TESTS

\T OHIO

STATE uni\t:rsity

Coal Fired per Hoi-r Drv'i

DED BY i/ Draft

Ratio of

Percentage

Pounds of
Coal Burned

of .\sh

per .Square

Fused to

of Fire,

Coal

Test

1st 3 Hours

2d 3 Hours

3d 3 HoUrs

2d to 1st

3d to 1st

Clinker

per Hour

Inches Waler

Inches

Per Cent.

zj i i -: =

1

1105

785

513

0 71

0 46

34

24

0.30

.s

78

t^f^t-c

2

793

0 81

0 68

29

25

0 .30

10

62

.•?

1103

866

607

0.78

0.55

24

24

0 30

6

»^E5,?

4

SCO

708

624

0 89

0.78

12

19

0.30

4

127

,5

1180

754

462

0.64

0.39

42

17

0.20

8

72

O^ --. .

6

973

817

688

0.84

0.71

34

27

0.40

8

81

7

960

863

755

0.90

0.79

25

29

0.51

8

88

= o.-^Zu^

8

957

777

676

0.81

0.71

35

21

0.29

8

79

1007

745

692

0.74

0.69

22

28

0 51

6

95

1028

807

646

78.5

63 0

1

1

608

595

615

98

101

3

17

0.31

4

187

^•fa g - £

2

1125

1020

815

91

72

17

25

0.32

S

90

- &=•=

3

910

925

1130

102

124

14

31

0.30

12

67

4

782

758

705

97

90

28

32

0-50

10

112

.1

800

930

858

116

120

18

28

0.30

10

78

<5" -^

6

895

950

798

106

89

21

27

0.32

12

84

- I. = £ £.t;

7

650

866

728

133

112

19

18

O.IS

9

89

8

1070

1100

1260

103

118

07

20

0.15

9

76

9

740

768

768

104

104

18

36

O.Sl

14

80

842

879

864

104

102

i

oj.^ii

-' -cCs

1

1 .ilid

1177

11 HI

S6.5

83.8

58

16 3

0 20

6

42

2

i:il(i

1173

los.-.

89.5

82.9

51

16 2

0 19

S

43

3

107.-)

916

916

85.2

85.2

50

15.7

0 31

7

74

4

1125

857

693

76 0

61 5

67

15.9

0 18

u

54

5

1145

867

970

7.5 7

84 6

47

15 9

0.17

s

78

a S.2 ~ c i

6

1122

746

654

66.5

58.3

64

14.9

0.18 ■

7

41

1189

956

909

80.4

76.4

g£o|£-3

perafure will give some trouble on al-
most any kind of stoker, either by bridg-
ing over the dump grate, sticking to and
clogging the moving bars, or by cutting
off the inflow of air through the grate
and thereby allowing the grate to become
hot and burned. As a rule, the detri-
mental effect of clinkers on mechanical
stokers is not to gradually decrease the
rate of combustion per unit draft, but
results in the extra labor of cleaning
fires, cost of stoker repairs, or sometimes
by stopping the stoker.

Effect of Sulphur
There is a prevalent opinion that high
sulphur in coal is the cause of clinker
trouble. While there may be cases where
a coal high in sulphur will make a more
troublesome clinker than another coal
with a lower percentage of sulphur, yet
the sulphur usually has very little to
do with it. Some of the sulphur in coal
usually exists in combination with iron
as pyn'te, and in some cases the iron
tends to act as a flux to the remaining
ash and causes a reduction of the fusing
temperature of the mixture. Much the

TAHM: 4. .MISCEI.I.ANEOrS results showing EFFECT OF FUSING TEMPERA-
TURE. ASH. SULPHUR AND IRON

Fusing

Temperature
of Ash.

Sulphur in
Coal.

Iron Oxide

1 leprees

.\sh in Coal,

in A.'ih.

No.

Character of Coal

Fahrenheit

Per Cent.

Per C«nt.

Per Cent.

1

Anthracite

31.10
3070
2910

14.85
14.81
7.97

0 76

1 36
0 96

2

.T

S.'mibiliiminous

7 0

-1

.-MmilMtiiminoiiK

2880

7 33

0 70

10 0

.-i<-mibiliimmoii.i

2830

13.85

1 78

0

Hiliiminoiis

27.W

10 60

0 60

7

.■<<-mihiniminou.«

27.'.n

5 80

0 71

s

.s«.mihininiinoii,s

2710

7 84

0 96

7 90

9

.•vmihlliiininoiis

26S0

10 61

I no

in

.■v'miliitiiminoiiK .

2640

S 90

1 25

12 0

II

lia."

2640

9 84

0 72

0 0

12

.Semihiluminoiis

2610

8 93

2 14

13

.Semililliiminowi

2610

8 ei

J 2»

14

SemihltuminniM

25.V)

12 85

3 10

23 7

Gat

2.'.20

7 22

1 22

13 0

16

Anihracile

2520

10 08

0 61

6 1

17

nitiiminoii!!

2510

8 02

1 12

l.s

.><eniibitiiminnii«

2480

4 9-

0 70

19

Gai

2460

6 91

2 35

.-'1 7

20

Coke

2460

g 51

0 80

21

2A-iO

7 20

0 84

22

^•■mlhiliimlnond

2440

8 08

3 42

23

2360

9 .30

2 29

21

Semiliiliimlniiu-

2320

13 Ofl

0 92

7 1

2.%

23rifl

6 78

0 9R

10 6

26

KitiiminniH

22t«l

10 47

3 10

I .a~

22<W>

7 2.1

3 12

34 0

'*.

^' TriilMliirniniiii-

22.V)

7 II

n 73

12 9

"1

' 'ik.'

2100

in 22

1 to

13 9

:ll

-miMlmni -

Semihitiiminn'i

2170
210(1

5 .".n

11 71

32

nituminoiw

2140

21

806

POWER

November 28, 1911

mined the iron in the ash, thinking it
was an indication of the clinkering prop-
erty of the coal or coke, while other in-
vestigators have attempted to find a rela-
tion between lime and clinkers. A mis-
cellaneous group of results as to fusing
temperature, ash, sulphur and iron are
given in Table 4, arranged in order of
their fusing temperature. It is impos-
sible for any one constituent of the ash
to be the controlling factor when it is
the interrelation of each of the seven
or more constituents to all of the others
which affects the fusing temperature. It
may be possible to ascertain the relative
clinkering property of different coals
from the complete analyses of their ash,
but. so far, no one seems to be able to
interpret the results of the analyses after
they are made. Making them requires
considerable time and is more expensive
than is the detennination of the fusing
temperature of the ash. This one deter-
mination gives all the useful information
desired from the proper interpretation of
the complete analysis of the ash.

The color of the ash is often looked
i:pon as an indication of its clinkering
property, but there are so many excep-
tions to this rule that it cannot be con-
sidered a rule at all.

Much work has been done in connec-
tion with the preparation of coal at the
mines and its effect upon the clinkering
property of the coal. In some cases, the
better-prepared and lower-ash coals have
the higher fusing temperature, while in
many others the reverse is true. When
the impurities are of a slaty nature, con-
taining a high percentage of alumina,
they tend to increase the fusing tempera-
ture, while with others, such as lime, an
increase may lower the fusing tempera-
ture, but if a still larger percentage of
lime is added, the fusing temperature
may ultimately be raised. Thus it is
feasible that coal ash may be treated by
adding some material, such as alumina
or clay, to reduce the trouble due to
clinkers. A larger percentage of ash
that will not form clinker is often prefer-
able to a smaller amount that slags or
clinkers badly.

The seller of coal cannot guarantee a
certain evaporation in a plant because of
the varying conditions affecting the boiler
efficiency, but he can and does guarantee
to deliver coal of a certain heating value.
The seller cannot justly be held re-
sponsible for trouble due to clinkers
when it is the fault of the fireman, but
the purchaser can specify the fusing tem-
perature of ash desired and see that it is
delivered. This factor is of equal and
often of greater importance than the heat
value; for what is to be gained by paying
a premium for a few extra B.t.u. when
the formation of clinker may retard and
prevent their development, as clinker af-
fects both the capacity and efficiency of
the plant, as well as the repairs to the
furnace and its equipment.

Pipe Threading Dies*

No matter of what composition, the
greatest difficulty in threading pipe lies
in the use of dies which are often in-
adequate to perform the duties expected
of them.

Steel pipe can be threaded just as
quickly as iron, its wear is less on the
dies and it is preferred by the operator.
But to insure a good threaded joint be-
tween the pipe and the fitting, a clean,
smoothly cut thread must be had, aiid
this can only be secured through a die

A chaser of an improperly made die
is shown in Fig. 2; the square cutting
edge pushes the metal off, leaving a
ragged, torn thread. This die not only
makes a poor thread, but also causes ex-
cessive friction and is less durable.

Chip Space

This is the space required in the holder
in front of the chaser to allow room for
the accumulation of chips, Fig. 3, and
also provides means for lubricating the
chasers. This space should be provided
as in Fig. 3, which shows the chip spac;

Thread Cu i , i
Made Chaser

?ERLv Fic. 2. Result Obtai.ned with I.mprop-
ERLY Shaped Chaser

consisting of a frame and a set of chasers
with proper consideration for lips, chip
space, clearance, lead and a sufficient
number of chasers.

Lip

The lip is also known as a hook or a
rake, and is the inclination of the cut-
ting edge of the chaser to the surface of
the pipe, as shown in Fig. 3.

The lip may be secured by milling the
cutting face of the chaser, as shown by
the full lines, or by inclining the chaser,

in front of the chaser, with its back well
supported. A lack of chip space will
cause the chips to clog and tear the

threads.

Clearance

Clearance is the angle between the
threads of the chasers and the threads
of the pipe. This clearance may be
secured in various ways, depending. upo:i
the position in which the chasers are held
in the frame. The position of the cut-

• --^ Ppsifion

Fig. 3.

as shown by the dotted lines. The lip
angle should be from 15 to 25 degrees,
depending upon the style and condition
of the chasers and chaser holders.

In Fig. 1 is shown a chaser of a prop-
erly made die; the chips curl off clean
and leave a smooth thread.

•From tlie Septemljci' liullctiii ot the Na-
tional Tube Company.

Fig. 4.

ting edge of the chaser, in relation to
the center line of the pipe while working,
determines whether the chasers shall be
set "out" or "in" while the teeth are
being machined; see Figs. 3 and 4.

Lead

Lead is the angle which is machined
or ground on the front of each chaser to
enable the die to start on the pipe, and

November 28, 1911

POWER

807

also to distribute the work of making
the first cut over a number of threads.
The lead may be machined on or it may
be ground on after the chasers are
tempered. The proper amount of lead is
about three threads. As the heaviest
cutting is done by the lead, it should
have a slightly greater clearance angle
than the rest of the threads on the chaser.
When regrinding a chaser that has be-
come dull on the lead, care should be
taken to give each chaser the same
length of lead, as otherwise the work
will be unevenly distributed between the
chasers in the set.

Number of Chasers

To get good results in threading at one
cut, a die should have a suitable number
of chasers, the approximate number be-
ing determined by the size of the die.
Dies up to 1 ,'4 inches should have four
chasers; 1J4 to 4 inches should have ap-
proximately six chasers; 4 to 7 inches,
eight; 7 to 10 inches, ten; 10 to 12 inches,
twelve; 12 to 14 inches, fourteen; 14 to
18 inches, sixteen, and 18 to 20 inches,
eighteen chasers.

Oil

Use good lard or crude cotton-seed
oil in liberal quantities, as the best die
made will not produce good results with
poor oil.

A die made with regard to these points
by an experienced toolmaker will thread
both wrought iron and steel pipe with
equally good results.

Steel pipe is softer and tougher, and
consequently is more difficult to thread
with the old form of dies having the cut-
ting edge on the center, as shown in
Fig. 2; such a die pushes the metal out.
A better shape is Fig. 1, which has suffi-
cient front rake and relief to cut the
metal out with a clean finish without
waste of power or unnecessary friction,
similar to the working of a lathe tool.

Applying these principles to hand dies,
it is possible for one man to do the work
of two. In a paper by T. N. Thomson,
read before the American Society of
Heating • and Ventilating Engineers, in
IS06, certain tests are described on the
power required to thread pipe with hand
dies of the common pattern, and with
the same type of dies correctly made.
The author says:

"It shows that the power required to
thread mild-steel pipe with the new die
is not much more than that required to
thread wrought iron with the same die.
and much less than the power required
to thread wrought-iron pipe with the
cn-nmon die "

A patent has recently been granted
Henry P. White, of Kalamazoo. Mich.,
for a novel lubricating material which
includes crumpled sheet metal coated
with oil and powdered graphite and
folded and compacted together.

Steam Driven Air Compressor °"'y ^""^ through investment for increased

Economies

By E. C. Sickles
During the past it has been the prac-
tice to give but little attention to the cost
of operation in the medium-sized com-
pressed-air plants, and in some cases this

boiler plant.

Among steam-driven compressors which
have been used to a large extent may
be mentioned those employing the Meyer
valve on the steam end. This type of
valve is customarily used in conjunction
with a throttling governor, controlled by

Dollars per 1000 Cubic Feet
0.05 0.06 0.07 0.08 0.03 010

I { 1 1 1 1 { 1 1

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Dollars
Fic. 1. Cost of Fuel when Using Gas

250

300

holds true for the larger plants. First
cost has been the main consideration.

Single-stage machines compressing to
90 or 100 pounds have been purchased
with simple steam cylinders, operating
at 125 pounds steam pressure at the
throttle. These have operated for years
in localities where the fuel cost is high,
and where difficulties were encountered,
due to dust and carbonizing effects, with
consequent losses in economy and explo-

0.70 0.8

air pressure. As the valves are hand set,
under varying conditions of load without
constant attendance it becomes neces-
sary to arrange the valves to cut off at a
fixed point, necessarily so late as to prac-
tically eliminate all the economies which
might be expected if the compressor were
driven under fixed conditions and constant
output. If the Meyer valves are set at
an economical cutoff, and a heavy load
comes upon the machine, it will stop, and.

Dollars per Ton
090 1.00 Lie m LTO 1.40 1.50

'MM

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-Annual Fuel Co
on 10 Hours for

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Fic, 2. Cost of Fuel when Using Coal

250

sions due to extremely high temperature
conditions and troubles in lubrication.

Improvements have taken place more
readily in the air end by the adoption of
the iwn-stagc compressors, with conse-
quent economy, due to intercooling. and
case of lubrication because of lower
temperature. In the steam end, how-
ever, the most economical arrange-
ment of cylinders and valves has
not been followed ecnerally. and there
has been considerable loss in fuel econ-

the air supply may be cut off at consider-
able inconvenience. This type of valve,
if the attendant is not on hand to start it,
therefore, involves, under varying com-
pressed-air demands, either a loss in
economy or constant attendance. The well
known throttling type of governor, which
is the usual adjunct to this type of com-
pressor, does not permit the highest
steam economy.

It therefore hccnmcs necessary, even
where the fuel-supply cost per unit is

808

POWER

November 28. 1911

low, if the most economical commercial
results are to be obtained, to consider
carefully not only the design of the com-
pressor in detail, but also all the factors
entering into the cost of the compressed-
air plant. In the cost of a new plant this
would involve comparison of the cost of
the necessary boiler capacity installed,
the cost of the compressor foundations,
building and all other factors involved
in the complete installation. The annual
charges, based upon the total cost of the
compressor installed for the same capa-
city of output, added to the cost of fuel,
operation and maintenance costs, will

give the proper basis for comparison and
decision in the purchase of the most eco-
nomical compressor.

Since an air compressor is to deliver
a certain amount of free air, compressed
to a certain pressure, it is desirable in
securing bids that the steam consump-
tion be obtained, based upon 100 cubic
feet of air compressed to the desired
gage pressure.

On the accompanying charts are repre-
sented the annual fuel cost of compressed
air, based on 10 hours for 365 days,
when delivering 100 cubic feet of free-
air compressed to 110 pounds gage. Fig.

1 represents the cost when gas is used
for fuel under the steam boilers, and
Fig. 2 when using coal. The price of
gas is taken as varying from 5 cents to
12 cents a thousand cubic feet, and the
price of coal from 70 cents a ton to SI. 50
per ton. As a sample of what may be
expected from a compressor of approxi- .
mately 1200 cubic feet capacity, of com-
pound noncondensing steam end with an
economical valve gear and two-stage air
end, it might be stated that the steam con-
sumption per 100 cubic feet, compressed
to 110 pounds gage, is approximately 6.4
pounds of steam.

Confessions of an Engineer

Manager Woods, although kept busy
attending to his own department in the
factory, found time to drop into the en-
gine room from time to time.

After my experience with the CO:
recorder I began to look about for some
means of making a saving in the opera-
tion of the plant, but found no apparent
opportunity.

There had been some trouble with the
boiler-feed pumps failing, which neces-
sitated shutting down the entire plant
on several occasions and the condenser
had likewise been put out of service.
The frost had been manifest for several
weeks and the leaves were fast falling
from the trees into the pond from which
the boiler-feed water and condenser cir-
culating water were obtained.

When the Trouble Began

I was sitting reading the last copy of
Power (it came in almost newspaper
size in those days), when the assistant
reported that it was impossible to keep
the vacuum at 26 inches and that the
engine was running below speed. Al-
most at the same instant the fireman
reported that the steam pumps w'ere not
getting enough water to supply the boil-
ers and that he could not keep the plant
going much longer as the water was al-
most down to the bottom gage.

Here was a situation which would
make an engineer wish he were n hod
carrier. With a limping condenser, an
overloaded engine and the feed pump
refusing to deliver enough water to the
boilers, it was enough to cause the en-
gine-room crew to rush about as frantical-
yl as rat terriers.

Realizing from the action of the pumps
that they were not getting enough water,
I at once decided that the strainer on
the foot valve had become clogged with
dead leaves and grass. The reason that
both feed pumps were affected was be-
cause they were both connected to the
same suction pipe. The condenser cir-
culating pump was connected to a sep-
arate suction pipe which entered at the

By W. O

. Warren

Tlic pump

suction pipes

became clogged with dead \

leaves, which

shut down the

plant.

Engineer I

'arren failed

to prevent a

second shut-

down and the

manager de-

cided to purchase a double |

strainer for

eacli Slid ion

pipe.

same pit with the pump-suction pipe. The
gate was shut in the suction-pipe intake
pit and the foot valves were cleaned of
their accumulation of leaves. This had
necessitated shutting down a part of the
mill and Wood was running around as
busy as a bird dog.

Little "Rackets" Cost Money

When matters had been straightened
out and normal conditions obtained. Wood
came into the engine room and said:

"That little racket cost the company
over S200."

"Was it as much as that?" I exclaimed
in surprise. The fact is, I had never
given any time to thinking how much
the stopping of the machinery would
amount to in wages and decrease in fin-
ished products.

"All of that," replied Wood. "We have
over 1000 hands employed in the mill
and each will average 20 cents an hour.
The plant was shut down for more than
30 minutes. That makes a loss of SlOO
for wages alone and the other SlOO is in
the loss of output. Dead leaves are
costly."

"I should say so!" I exclaimed. "But
this has only happened once, or at most
twice, a year," I added, with self-satis-
faction.

"Once or twice a year is altogether
too often," replied Wood. "We have got
to find some means of getting over this

trouble at once. I suppose a duplicate
suction pipe for both the boiler-feed
pumps and circulating pump would be
about the best way out of the diffi-
culty. Then there will be two pipes to
depend upon instead of but one. I would
not like to go to the expense of a dupli-
cate line just to prevent trouble for two
or three weeks during the year."

"We might put in a screen and do way
with the new suction pipe," I suggested,
as I labored for something better to say.

"The trouble with such an arrange-
ment," answered Wood, "is that it is only
good for preventing large pieces of foreign
matter from getting into the suction
pipes. In the fall of the year the dead
leaves and grass clog them up about as
fast as they can be cleaned out, and I
do not see that w-e would be any better
off than we are at present.

"I have seen racks and screens used
in a great many cases, but they have
never been thoroughly satisfactory. I
suppose we might fit the intake pit with
two screens so that when one gets
clogged up it could be lifted and cleaned
while the other would be in service."

A Lost Opportunity

Shades of smoke! Why had not I
thought of this before Wood did? Here
I had been looking the plant over from
top to bottom for a chance to make good
on improvements and Wood had scored
again. I had read the description of a
straining device that had been placed
upon the market but a few weeks be-
fore, and it was just what was wanted.
There was no use in crying over sour
apples and so I said:

"Why not get one of those new double
strainers which have just been put on
the market? I know that one on each
of our suction pipes will remove the
trouble we are having."

"What are they like?" asked Wood,
pricking up his ears.

Why, they are just two strainers
placed in a metal casing. The casing
is fitted with two valves so that the

November 28, 1911

POWER

strainer which is being used can be cut
out of the path of the water going to the
pump."

"I do not see that this device would
help matters much," answered VC'ood.
"When one of the strainers gets clogged
up the whole thing has got to be taken
up out of the water, which, to my mind,
is no better than having a couple of
screens to fit in the intake frame and will
not cost one-tenth as much."

"Oh, no!" I hastened to reply. "You
have not got the right idea. This strainer
does not have to be submerged. It can
be placed in the suction pipe at any
place between the water supply and the
pump. When it is necessarj- to clean
one of the screens, just shut it out of the
line by means of the valve and then
remove the cover on the casing, when the

"Yes, but you knew the value of this
strainer device, didn't you ?" asked Wood.

"Yes," I said, "I sent for a catalog
which described it, as I do for everything
I see that is new."

"Well, you knew that we were troubled
with leaves clogging up the foot-valve
strainers of the circulating pump, didn't
you ?"

"Yes, I knew about that, but the trouble
only occurred once or twice a season and
the plant is shut down only about half
an hour each time. Besides that. I ex-
amine the foot valves about this time of
the year to be sure that they are clean."

"How do you clean them? I did not
know that you had taken the pipes up."

"I didn't; I used a long-handled rake
and scraped the leaves off the strainer,"
I replied.

I Felt Like Kicking Myself for Not Having Had Enough Gumption to
Reco.mmend the Purchase of Suction-pipe Strainers

screen is easily removed and cleaned
while the other strainer is in service."
"That sounds good, but why in Sam
Hill didn't you say something about
this thing before? You know that we
have had this same trouble year after
year and it has cost the company a lot
, of money first and last."

Seeing Ahead

Why? I do not know, unless it was
because I was like many other engineers;
I was not capable of seeing ahead. I
had to have the thing demonstrated be-
fore I could grasp the full significance
of its utility and value. Perhaps the
reason why I had never noted my short-
comings was because I never before had
a manager who took any interest in the
steam plant.

There was not much that I could say
in reply to Wood's question, but I lamely
replied: "I did not suppose you would
care to put out much money on any-
thing which would be used but once or
twice a year."

"Well, it did not do much good." re-
plied Wood. "I suppose you have done
the same thing each season?"

"Sure thing!" I answered with haste,
glad to be able to assure him that I
had been attending to my work.

"It seems to me that, after finding out
that the raking process did not work, you
would have looked after some other
means of taking care of the foreign re-
fuse matter in the water. I think we will
get a strainer for all of our suction pipes
and see if we cannot stop this shutting
down because a few leaves get into the
water. Is there anything better on the
market?"

"Nothing that I know of," I replied.
"1 do not see how anything could be more
simple than these strainers. It is simply
a matter of cutting the pipe, putting on a
Pange on each end and screwing these
flanges on the pipe to the flanges on the
strainer case. After that, as I have told
you. it is simply shifting the water from
one strainer basket to the other, and
then clean the dirty basket."

The Manager Acts

"Well, that looks good to me," and so
saying. Wood left the engine room and,
as I afterward learned, telegraphed for
two strainers for the boiler and one for
the condenser circulating-suction pipe.

Here was an opportunity to show that
I was capable and was looking out for
my employer's interest, but it had gotten
past me and had been picked up by Wood
while I was looking for something big
with which to make a saving.

I have since learned that there are
thousands of engineers who are in the
same boat; that is, looking for something
big to do instead of looking after the
small details of power-plant operation.

Leather Piston Packing
A service pump in a street-railroad
power plant gave considerable trouble
by water slipping past the plunger. The
engineer could find nothing that would
remedy this trouble until he tried ordi-
nary leather packing rings, six in num-
ber, which easily fitted in the water cyl-
inder when dr>'. These were placed on
the piston the same as ordinary packing
and the follower plate and nut put in
position.

Plunger Packed >xith Leather

Since using this method of packing
the water plunger, the pump will often
run 18 months without attention.

.\ combination of a steam turbine and
an internal-combustion engine has been
patented by John I. Thomycroft & Co.,
Ltd., of England, and .1. E. Thornycroft,
for the propulsion of high-speed ves-
sels, such as torpedo-boat destroyers, in
which it is desired to solve the problem
of propelling the vessel economically
under varying conditions. It provides
for an installation of turbine plant equal
to the maximum propulsive power re-
quired (say, 15,000 horsepower dis-
tributed on twin shafts), and for an in-
ternal-combustion engine of requisite
power to drive the vessel at low or
cruising speeds. The internal-combus-
tion engines arc preferably oil engines
of the Diesel type of 1200 horsepower, in
units of 600 horsepower, each on the
twin-shaft arrangement. The internal-
combustion engine is placed forward of
the turbine, and a clutch is provided to
couple the engine to the propeller shaft
— Mechanical World.

810

P O W B R

November 28, 1911

"Diamond" Soot Blower

A new design of soot blower has re-
cently been completed by the "Diamond"
Power Specialty Company, Detroit, Mich.

with a sufficient number of jets to
cover the entire boiler end. There
are angle jets on the end of each arm
to care for the cleaning of the outside
and lower tubes.

Fig. 1. New Tubf Blower Applied to a Return-tubular Boiler

This front-end blower when used on The new design of tube blower for

return-tubular boilers is made with four Stirling boilers is shown in Fig. 2. It

arms which swing in a quarter circle, consists of four units. Each unit is

and which are operated from the outside equipped with two nozzles and swings in

Fig. 2. Tube Cleaner Applied to a Stirling Boiler

of the setting by a handle, as shown in
'Fig. 1.

The blower is bolted through one of
the front doors and each arm is studded

and out of the cleaning doors. One unit
is operated at a time and when not in
use it is swung to the outside of the
boiler setting. Each unit is also provided

with a drain cock to free the pipe from
condensed steam before blowing the
tubes.

Belt Hook Tool

A new tool for inserting wire belt
hooks in leather belting has recently
been patented by A. M. Delvalle, 1432
Pacific street, Brooklyn, N. Y.

The tool shown in Fig. 1 consists of a
base upon which the belt is placed and
which also holds the belt hook, as shown
in Fig. 2.

Fig. 1. Hooks Ready to be Closed

The clamping head is actuated by a
handle and ball joint, shown in Fig.
1. When the head is brought down
against the hook the top and bottom
points are forced into the belting and

Fig. 2. Hooks as they are Placed in
THK Tool

the two ends are hooked over, one in-
side of the other. The hooks are held
in position in the clamp by a holding
plate and rod which passes through
the loop of each hook.

Fig. 3. How the Joint Is Made

The hooks are placed in the belt stag-
gered and the links of the hooks in each
end of the belt are held together by
either rawhide or brass pins, as shown
in Fig. 3.

November 28. 1911

P O \V E R

811

Strode Condenser Packing
Tool

A new design of condenser-packing
tool has recently been perfected by Ed-
ward P. Strode, 131 East Thirtieth street.
New York City. The tool is operated by
compressed air and is so designed that it

H a longitudinal finger J. It is grooved
at its outer end and has a spiral spring
insened in a hole, the arrangement being
such that normally this finger is held
at its outer end against the inner face
of the small end of the barrel. The
spiral spring K is for the purpose of re-
turning the reciprocating plunger to its

winds the packing cord around a spindle
and then pushes it into position around
the condenser tube when the operator
presses a finger and a thumb trigger,
which control the two operations.

The illustration. Fig. 1, shows a sec-
tional view of the device, A representing
the body part of the tool which is in-
tegral with the handle. The barrel is
made with a reduced outer end, and the
parts are secured by screw threads, as
shown. The tubular reciprocating plunger
E Is provided with a piston B which ac-
curately fits within the barrel C. A rotary
shaft fits within the inner guide tube
and is provided with an enlarged jour-
nal bearing at its outer end. The end of
this enlarged part is turned down into
the form of a frustum of a cone, as in-
dicated at F, and is provided with a
shoulder which fits against the end of
the tubes around which the packing is

Fig. 1.

Sectional View of Strode
Packing Tool

nonnal position after it has been actuated
by the compressed air.

A longitudinal slot to the small end
of the barrel constitutes an opening for

Fig. 2. Strode Condenskr Packing Tool

to be inserted. This enlarged part also
constitutes a cylinder around which the
packing cord is wound before the tool
i.o put into use. To secure this cord a
longitudinal groove is provided in the
body part in which is pivoted upon a pin

Ihc insertion of the packing cord. The
air supply is conducted to the handle of
Ihc tube through a rubber lube. In ihc
bottom of the handle is an opening /.
which runs to the body of the valve
where it is divided into two channels.

one conveying the compressed air to the
piston and the other to the driving motor.
The valve ,11 is held in a seated position
by a spiral spring, and the valve is'
actuated by means of the trigger N.

The operative part of a rotary motor is
shown at O. It is secured to the rear
end of the breech of the tool and the
shaft P actuates the rotating shaft R of
the tool. A detachable cap is secured to
the casing of the motor and is provided
with a journal bearing. A pinion carried
by the shaft P meshes with the gear
wheel which rotates on a bearing jour-
nal that is secured to the breech. An-
other pinion is carried by a shaft in-
tegral with the gear wheel and measures
with a second gear wheel that is secured
to the rotary shaft R. A second valve
is kept seated by the pressure of a
spring in the channel running to the
rotor of the motor. This valve is op-
erated by the lever T which is worked by
the pressure of the thumb. Air vents are
provided for liberating the air after it
has passed through the motor.

When using the tool one end of the
cord is inserted at the outer end of the
slot shown at the small end of the bar-
rel in Fig. 2. Air pressure is then ad-
mitted to the motor by merely pressing
a trigger with the thumb. The motor
rotates the spindle S, thereby drawing
the cord through the opening and wind-
ing it around the spindle. The cord is
I'len in a position to be forced on the
tube end by the reciprocating plunger.
The operator presses the finger trigger a
ni-mber of times in succession until the
cord has been driven home, the number
of blows depending upon the density to
be given to the packing. In this way
the operator passes from one tube to
another in quick succession. The aver-
age operator can easily pack a con-
denser at the rate of from 10 to 15 tubes
per minute, and as many as 28 tubes
have been packed per minute.

Ciraspit Belt Dressing
A new preparation has been placed up-
on the market for cleaning, softening and
restoring leather belting to its natural
condition. One grade is suitable for use
on rubber, canvas and cotton belting, and
another grade is made for rope transmis-
sion.

This dressing is also suitable for use
on oily bells, and after the application has
been made and the bell has absorbed
the dressing, further oil is prevented
from penetrating the leather as the belt
has been made water and oil proof. A
small quantity of the preservative is put
on the face of the belt while it is in
motion. If is said by the manufacturers
that sicatn or heal will nni affect the belt
after this dressing has been used. It is
made by the Graspit Manufacturing Com-
pany, 723 Hast Thirty-ninth street, Chi-
cago, III.

P O W F. R

November 28, 1911

Twinlok BlowofF Vah'e

The improved twinlok blowoff valve,
illustrated herewith, is manufactured by
the Twinlok Specialty Company, St.
Marys, O.

The improvement consists of the ar-
rangement of two valves of the rising-
stem type with their respective stems
parallel and an interlocking tumbler
pivoted at A, Fig. 1, which is placed be-
tween them. This tumbler has a pro-

FiG. 1. Sectional View of Twinlok
Blowoff Valve

jecting lug so arranged that the valve
stem, shown at the right of the illustra-
tion, cannot be unscrewed before the
stem at the left, upon which is mounted
a removable handwheel, is unscrewed to
its full hight. When the collar B has
risen with the steam until it has
reached a point opposite the de-
pression C in the interlocking tumbler,
the handwheel can then be shifted to
the right-hand valve stem after moving
the interlocking tumbler to the left until
the projecting lug disengages the collar,
when the right-hand valve stem may be
raised to its full hight. It is then neces-
sary to close the right-hand valve be-
fore the interlocking tumbler will pennit
closing the left-hand valve.

This device obliges the operator to
open wide the varlve nearest to the boiler
or high-pressure side before even partly
opening the other, and he is likewise

compelled to close the latter or throttling The wrench will take either square oi

valve before he can close the stop valve, hexagon nuts, and does not have to be

The valve is designed with the idea of taken off the nut in advancing, as it rides

around the edges or corners and the
grip is taken as desired. It is of the
quick-action, self-adjustable type. The
clamping effect of the pipe and jaws is
obtained through the rotation of a disk
which comes in contact with the pipe by
means of a spring pulling the saddle
toward the head. Pressure on the handle
causes the disk to rotate inw-ard, the
pinions attached to the disk on both
sides engaging the teeth in the handle,
thus causing traction toward the head.
The grip is, therefore, increased in pro-
portion to the pressure on the handle
and is readily released by suspension of
the pressure. As will be noted, a three-
point contact on the pipe is obtained.

Fic. 2. Exterior of Valve

bringing all wear upon the outside throt-
tle, the seat and valve of which are re-
newable.

Combination Wrench

The accompanying illustration shows a
wrench designed for pipe and other work
recently developed by the Atwood
Wrench, Tool and Stamping Company,
Conneaut, Ohio.

The tool is made of cold-rolled steel,
except the smaller parts which are made

Klie-Rite Pulley Covering
This pulley covering, which has been
on the market for a year or more in
this country, is being sold under the
American rights by the American Klie-
Rite Company, 919 Hippodrome building,
Cleveland, O.

The preparation, which is an adhesive
compound, is applied to the face of a
pulley to prevent the belt from slipping.

Duplex Akron Metallic
Gasket

The Akron Metallic Gasket Company,
Akron, O., is producing a new corrugated-
copper gasket which consists of two regu-
lar corrugated-copper gaskets which are
held together on the inner edge by a
double lap. The gasket is then annealed
until it is soft and pliable. It is then
coated with a graphited cement coating
to give contact with the flange, and to
prevent sticking to the flange when break-
ing the joint.

The new gasket is so held together by
the double lap that it cannot slip apart.

Combination Quick-acting Wrench

of tool steel, and the head is welded to
the handle after the latter is formed from
the flat, thus giving ample tensional
strength.

and the double lap on the inner edge
gives extra thickness at the place the
flanges pinch the least and where the
greatest steam pressure comes.

November 28, 1911

POWER

813

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Power House Lighting

By C. E. CLE^S•ELL

"We can make repairs much easier
and quicker with our new lights; they
don't go out just at the wrong time and
are steady and don't flicker.

"Our engineer can see all around the
machines as well at n:2ht or on dark
days as in bright daylight; the switch-
board man says he can read the instru-
ments quicker and can work on the bus-
bars and on the connections behind the
boards; also the fireman can see his
valves and gages easier. We can find
pending trouble before it happens and fix
it at once."

Such is the essence of the comments
of a station man who had a new lighting
equipment installed in his power house.
Why had the old arrangement been al-
lowed to go year after year when a
change, apparently very simple, had done
so much to increase the efficiency of op-
eration of the plant?

To answer this question would be to
record the phenomenal development of
the past few years in the remarkable in-
ventions of electric lamps and in the
great advancement in the methods of in-
stallation. These are the chief reasons
why lighting results are now possible
which hitherto could not be realized.
Minor reasons are the previous lack of
exact information as to how to distribute
lamps in order to illuminate certain ap-
paratus and instruments; how much
light was necessary for a given space,
and the hight at which lamps should
be placed. This article is intended to fit
the needs of the station man or superin-
tendent who is responsible for the light-
ing of his olant, by giving him answers
to some of the questions covering the
features just mentioned.

Artificial lighting has received little at-
tention in the past because people have
regarded lighting as a commonplace sub-
ject, devoid of any need for expert con-
sideration. Another reason has been the
limited sizes of lamps available. Take
the average small power house as an il-
lustration. If the ceiling was low, clusters
were used here and there, equipped with
carbon-filament lamps, or perhaps arc
lamps were utilized, with extension lines
for close work. The results of such
methods were usually unsatisfactory.

During the past 10 years, however,
tamps of intermediate power have been
introduced, notably the fungsten-flla-
ment, the Nemst and the Cooper Hewitt

Therefore it will be found advantageous
to control only a few lamps from one
switch, so that only those lamps actually
needed are burned at any one time.

lamps, all having candlepowers lying be-
tween those of the arc and the carbon-
filament lamp.

Si.vPLE BUT Important Principles

The station manager should realize
that the expense for adequate light is

General versus Definite Rules

Most practical men want definite rules
which will give definite results after the
work is done according to the rules. This
is difficult in lighting work on account of
the many variable factors which affect
the result. It would be almost as diffi-
cult as to specify the station wiring with-
out knowing the allowable voltage drop,
the distances involved, the current values
and the like. If the ceiling and the walls
are dark, more or larger lamps will be

Fic. 1. Showing Old Arrangement of Large Lamps and New Spacing of
Small Lamps

a small outlay when compared with the
indirect saving in labor and material in
the station upkeep as well as in im-
proved service brought about by time
saved in making repairs, locating trouble,
etc.

It is most important to choose a lamp
adapted to the surroundings and to the
cl.iss of work performed. Unshaded light
shining into the eyes makes it hard to
sec things even if they arc brightly il-
luminated, especially where the walls
and machinery are dark. The way to
avoid glare is to raise the lamps so
that one is not apt to look into the light
itself, and to use reflectors or globes
which shield the intense light from the
eve.

If all the lamps are on one switch,
some are likely to be on when not needed.

required than if they are light colored
It is perhaps best, therefore, to give
some of the items connected with suc-
cessfully lighted power houses from
which the practical station man may de-
termine for himself whether or not the
conditions and the arrangement apply to
his own particular case.

The lamps should be operated from
constant-voltage mains to prevent the
annoyance of unsteady light.

Intensity Required

The best and most commonsense test
of this item may be summed up in the
question; "How well can the work be
seen not in a passing glance, but when
working under the light for a con-
siderable length of time? After measur-
ing the amount of light found necessary

814

POWER

November 28. 1911

in the average power house it has been
found that from two to three foot-candles*
is generally sufficient. This does not
necessarily mean that this intensity is
needed at all times, but the lamps should
be installed so that by a suitable switch-
ing arrangement this much light is avail-
able at times of emergency when it is
imperative to make repairs.

The station man may not be concerned
about foot-candles but instead may wish
to know how many lamps must be in-
stalled to furnish the necessary light. It
seems advisable to give general hints
only, because cases may occur where ad-
herence to definite rules will produce re-
sults far from satisfactory. If the walls

wide with a ceiling hight of 65 feet.
Cooper Hewitt mercury-vapor lamps
were mounted along the walls 25 feet
from the floor. In this installation 0.31
watt per square foot of floor space was
used.

Another plant, 170 feet long by 59 feet
wide with a ceiling hight of 76 feet, was
equipped with Cooper Hewitt lamps
mounted along the side walls 15 feet
from the floor, and here 0.46 watt per
square foot was used.

In another plant 0.28 watt per square
foot was used in the installation of
Cooper Hewitt lamps.

The watts per square foot of floor
space required to furnish adequate arti-

the watts per square foot of floor space
were about 1.3. This value is not, how-
ever, necessarily an index to the power
consumption, for while the value is some-
what higher than those with the Cooper
Hewitt lamp, it will be noted by refer-
ence to Fig. 1 that the lamps are con-
trolled in such a way that for general
lighting every other row may be used,
while in case of emergency a given por-
tion of the floor space may be more
brightly lighted.

Size of La.mps

In one large factory it has been found
that the size of lamps is best governed
by the ceiling or the mounting hight.

Fin.

Ill pFi-irT 01- A Larti: Ni'.mef.r of Medil'.m-sized Lamps

and ceilings and general surroundings
are dark, more or larger lamps will likely
be required than indicated in the follow-
ing examples. It is advisable, therefore,
to consider them as averages which
should be used with judgment.

Practical Instances
In one plant 374 feet long by 55 feet

•The foot-candle is the nnit of illimiin.i-
tion intensity and is usiinlly measured on a
liorizontal plane from 2 fo '.". feet alinve the
floor. An incandesi-ent lamp tlirowins K!
candlepower direcily downward, if mounted
4 feet al)ove a desi,," will produee an intensity
of 1 foDt .■nodlepDwer on tlie surface of the
de.sli : if niomii.il 2 feet al)oye the desk it
will nrndiK-e :in inli'usltv of -1 foot-i-:indles on
Ihe d.sU -juvfaee. That is to say. the inten-
sity of ilhiminalion varies as the square of
the dislanee hetween the lamp and the plane
on which the Ilaht is to lie used. It is equal
numerically to inmllcponcr -^ hiijliP.

ficial light depend on the efficiency of
the lamp used. For example, more or
larger lamps, which give 1 candlepower
per watt, will be required than if lamps
giving 2 candlepower per watt are used.
If tungsten lamps are chosen, it is pos-
sible that a somewhat higher number of
watts per square foot may be required.

In one power plant having light walls
and ceiling, with a floor space 128x75
feet and with a ceiling hight of about 24
feet, 250-watt tungsten lamps were in-
stalled with a spacing of 12x16 feet, as
shown in Figs. 1 and 2, the lamps being
mounted about 21 feet high. The curves
in Fig. 3 showing the distribution of
light are plotted from observations taken
along the lines A and B, Fig. 1. Here

Thus, where the ceiling is low, it was
found best to use small lamps to reduce
the glare and also to be able to use
enough lamps for providing uniform light
over every portion of the floor space.
For high ceilings large lamps were found
to produce good results.

In this instance 60-watt tungsten lamps
were used to advantage where the ceil-
ings were 8 feet high or less; for ceil-
ing hights of from 8 to 14 feet, 100-watt
tungsten lamps were used in a number
of cases: from 14 to 20 feet, both 100-
watt and 250-watt tungsten lamps: from
20 to 30 feet, tungsten lamps from 250
watts to 500 watts, and for ceiling hights
over 30 feet, arc lamps were used ex-
tensively.

November 28, 1911

POWER

815

Spacing of Lamps

If the size of the lainp is chosen for
use in a power house having a certain
ceiling hight, the spacing is practically

Under Bow of lo'nps

li

II

10

Between Rows of Lamps '"^'^

Stations

Fig. 3. Showing Intensity of Light at
Different Points

in the manner just described, but it has
been found expedient to sacrifice sym-
metry in those cases where a symmetrical
placing in the center of bays brings the
lamps farther apart than is fitting. In
such a case, the spacing having been
determined upon equally in both direc-
tions, the lamps may be installed so as
to clear the girders but need not be sym-
metrical with respect to them.

Mounting Hicht

In power houses the crane often deter-
mines the hight at which the lamps must
be mounted, unless they are placed along
the side walls.

Where there is a light ceiling it is ad-
vantageous to mount the lamps close to
the ceiling if the lamp is of a type which
allows some of the light to be thrown
upward, since the ceiling will in turn re-
flect this otherwise useless light. When
the ceiling is very high and the lamps
cannot be reached for renewals and re-
pairs from step ladders, it may be best
to place the lamps some distance below
the ceiling so that they may be reached
from the top of the crane. In such a
case the ceiling reflection will be sacri-
ficed in favor of a lower maintenance
cost. In general, however, lamps should

ficial light is first needed toward the
close of the day in the center of the
room and later near the windows. With
100- watt tungsten lamps from four to
six lamps, and sometimes two lamps per
switch, have been used to advantage;

Fig. 6. Cooper Hewitt Lamps in Boiler
Room

Fic.

4. High Candlepower Lamps in Engine
Room with High Ceiling

Fic. 5. Good Distribution with Cooper Hewitt
Lamps

fixed after the total watts necessary have
been found. Consider the power house
illustrated in Figs. 1 and 2. If 1.3 watts
per square foot were deemed necessary,
then the total floor space to be lighted
by one lamp is

250 ^ 1.3 ^ 192 square feet
which is equivalent to a square 14x14
feet. In this particular case the arrange-
ment of the building made it advisable
to mount the lamps with a spacing of
12x16 feet so that the lamps might hang
in the center of the bays, the area per
lamp being the same as before.

The details of the building will often
he found to govern the spacing of lamps

be mounted high and well out of the line
of vision.

When every other place supplied by
the power house is in darkness, due to
a breakdown, it is important that the
power house itself be well lighted so that
the necessary repairs may be made with
despatch.

Switch Control

The number of switches installed for
controlling the lamps should be governed
by the floor area covered by one lamp,
by the total watts allowable per circuit,
•ind by the location of the windows. It
is advisable to control lamps in short
rows parallel to the windows since arli-

with the 250-watt lamp two lamps per
switch has been found a satisfactory ar-
rangement. In general, the larger the
lamps used the larger the portion of floor
space lighted by a single unit; hence the
smaller should be the number of lamps
m a single switch circuit.

Maintenance

Globes and reflectors should be kept
clean. Great losses of light occur when
these accessories are allowed in become
soiled. Frequent washing of the glass-
ware is therefore strongly advised. It
has been found in certain very bad cases
that nearly double the power is required

516

POWER

November 28, 1911

to furnish a given amount of light when
the lamps and reflectors are soiled as
when clean. Burned-out lamps should
be renewed systematically and promptly.

Hints for the Various Locations

In the boiler room a row of medium-
sized lamps mounted on a level with the
upper portion of the boilers has been
found advantageous. Individual lamps
are placed over the gages and are fitted
with metal half shades which throw the
light on the gage and at the same time

In the engine room the ideas and
principles set forth in the preceding notes
particularly apply, and the illustrations
show some of the typical power houses
which serve as an idea of the general
arrangement and the uniformity of the
light where the lamps are suitably in-
stalled.

As an illustration of an old and a new
installation reference is made to the en-
gine room, shown in Fig. 1. The old
installation, consisting of six arc lamps,
is shown by circles. The watts per square

lamp small enough so that a large num-
ber of them could be used economically
and also by the use of a reflector for
directing most of the light in a down-
ward and useful direction.

Summary

In summarizing, the following princi-
ples and hints should be considered:

Adapt the size of lamps to the ceil-
ing or mounting bight.

The lamps should be spaced sym-

FiG. 7. Clusters of Small Lamps Mounted High but
Spaced Too Far Apart

Fig. 8. Individual La.mps Located over Machines, Result-
ing IN Glare AND Poor Distribution

9. Light Distributed by Clusters of Small
La.mps

An Old Method of Lighting-
Machines

-Cluster? over

protect the eye from the glare of the
lamp. The wiring along the boilers may
be placed in approved iron conduit, this
making a safe and reliable method.

The basement is usually low and iron
conduit is likewise useful here where
the conditions are damp. If the ceiling
is fairly high, as is the case in some
large plants, tungsten lamps may be
used in the more open parts of the base-
ment and carbon-filament lamps placed
over the pumps, valves, etc.

foot of the old installation were about
0.4 while that of the new are about 1.3.
The trouble with the old installation lay
in the fact that the light was not suffi-
cient and furthermore was thrown side-
wise, so that only a small portion reached
the floor where it was needed; the lamps
were too far apart and as a consequence
the spaces between the lamps were poor-
ly lighted. The new installation, con-
sisting of forty 250-watt tungsten lamps,
overcame these defects bv the use of a

metrically on squares with respect to the
bays if possible and practical, but not
if this requires a spacing much in ex-
cess of that called for by calculation.

The lamps should be mounted high so
as to avoid glare, compensating for this
by the use of reflectors.

The lamps and reflectors should be
kept clean.

The ceiling and walls should be painted
a light color and kept light.

November 28. 1911

POWER

817

The Buckeye Gas Engine

The accompanying engravings illustrate
the type of gas engine now being built
by the Buckeye Engine Cotnpany, Salem,
O. The engine has passed through the
usual course of evolution in design and
the views here shown represent the prac-
tically final status.

Fig. 1 is a general view of a tandem
double-acting engine, from which it may
be seen that the machine is of the side-
crank type now generally considered the
standard for this country. Fig. 2 is a

mounted that they can slide in guides on
their respective sole plates. The method
of attaching the cylinder to the main and

known Buckeye steam engine; the tail
guide is also machined to a circular arc,
although there is only one guide surface.

The engine operates on the four-stroke
cycle, and as to the general features of
construction it does not differ essentially
from other American engines of its class.
The chief differences are in the valve
gear, the method of governing and the
arrangement of the piston-rod packing.

Fig. 3 is a cross-sectional view of one
end of a cylinder, showing all of the ele-
ments of the valve-gear and governor
mechanism. The main admission valve /

Fic. I. Tandem Double-acting Bickeye Gas Engine

longitudinal section of the same engine.
The main frame carrying the crosshead
guides and the main bearing is anchored
positively to the foundation, but the in-
termediate and tail frames are so

other frames is so clearly shown in Fig.
2 as to render a description unnecessary.
The main and intermediate crosshead
guides are of the "bored" type such as
has been used for years on the well

and the exhaust valve E are operaied from
a single eccentric through wiper cams in
the well known manner. To the end of the
admission-valve rocker arm is pivoted a
lever B and the outer end of this lever is

Fir,. 2. Longitudinal Section of Tandem Engine

818

POWER

November 28, 1911

pivotally attached to the stem of the gas
valve G. The lever B fulcrums on a
roller on the end of an arm C which is
oscillated by the governor so as to shift
the point of the fulcrum nearer to or
further away from the end of the lever.
That part of the lever which rests on the
roller is curved to a radius having its
origin in the center of the pivot upon
which the arm C is mounted, in order
that the governor may shift the position
of the arm C without changing the posi-
tion of the gas valve G; this construction
also avoids subjecting the governor
mechanism to any increase or decrease in
friction between the roller and the face

roller to the left to decrease the travel
of the gas valve it also lowers the throt-
tle valve T and thereby reduces the area
of the opening through which the mixture
must pass to the main inlet valve.

The butterfly valve A is adjusted by
hand to regulate the proportions of the
mixture if that should be necessary.
Ordinarily, however, the gas valve G
is made of such a size with relation to
the air passages as to form the proper
proportion of gas to air for the kind of
gas on which the engine is to run, and as
long as the gas quality remains fairly
constant the butterfly valve A is left prac-
tically wide open. The various levers

long bushing which is renewable when
wear makes this necessary. The valve
cage is also water-cooled.

The valve-gear shaft, which extends
alongside the cylinders as usual, is driven
through bevel gears and a drag crank
from the outer end of the main crank
pin. This arrangement is shown in sec-
tion by Fig. 4, which also shows that
the governor is driven by bevel gears
from the countershaft between the drag
crank and the gear of the valve-gear
shaft. This relieves the governor from
disturbances due to torsional deflections
of the valve-gear shaft.

The mixing chamber and the exhaust

Fic. 3. Bl'Ckeye Valve Gear

of the lever B when the arm C is being
shifted. As the travel of the main inlet
valve is always the same, the extent to
which the gas valve G is opened depends
upon the position of the fulcrum roller
on the end of the arm C; any motion of
the governor weights outward, due to an
increase in speed, shifts the fulcrum
roller over to the left and thereby de-
creases the extent to which the gas valve
is opened the next time the cam opens
the inlet valve.

The movement of the arm C by the
governor produces another result, name-
ly, the throttling of the mixture delivered
to the engine. The double-cone valve T
is mounted on a tubular stem through
which the stem of the gas valve G passes
and the tubular stem is attached at its
upper end to the arm D which is fastened
to the spindle of the anti C. the combina-
tion forming a bell crank; consequently
when the governor shifts the fulcrum

and the throttling valve 7" just mentioned
are so proportioned that the mixture is
not appreciably throttled until the load
decreases to about three- fourths of the
rated load ; between this point and maxi-
mum load, therefore, regulation is ef-
fected entirely by changing the quantity
of the gas admitted. Below three-quarters
load the fulcrum roller on the end of
the arm C has a relatively small travel,
due to the arrangement of the linkage
with the governor, and the throttling ef-
fect, therefore, predominates very great-
ly from this point down to no load.

The exhaust valve is water-cooled, of
course, and its construction is illustrated
in Fig. 3. The stem is tubular and a
small pipe extends through it into the
hollow head of the valve; cooling water
is admitted through the central tube and
passes out between that tube and the
wall of the valve stem. The guide sleeves
for the valve stem are provided with a

Fig. 4. Governor and Lay Shaft Drive

pipe are bolted directly to the cylinder
casting independently of the valve cages;
the latter, therefore, may be removed
without breaking any pipe connections.

The construction of the piston and rod
is shown more clearly by Fig. 5 than by
Fig. 2, on account of the larger scale.
The rod from the front crosshead to the
intermediate crosshead is continuous,
but there is a short length of enlarged
diameter at the center and an integral
collar at one end of this enlarged diam-
eter; the other end is threaded to take
the clamping nut which holds the piston
against the collar. The diameter of the
rod from the threaded portion to the end

F:g.

Piston Construction

is smaller than that of the threaded por-
tion so that the nut may be readily
slipped over the rod until the thread is
reached. After the nut is set up tightly
in place it is pinned to the face of the
piston so that it cannot back off. The

November 28, 1911

POWER

810

other face of the piston and the collar
on the rod are similarly pinned together
tn prevent the piston from turning on the
rod. This is necessary both for the
purpose of maintaining the alinement
between the inlet and outlet water pass-
ages in the wall of the rod and in the
core of the piston and in order to pre-
vent the nut from being backed off the
thread on the rod. The two piston rods
are exactly alike and therefore inter-
changeable.

The connecting rod is of the solid-end
type with mortises for the boxes cut
through the solid slab. Wedge adjust-
ment is provided for the boxes at both
ends. The crank, counterweight and
crank pin are all in one casting of steel.

twin form; in fact, they are built in any
combination from the single-cylinder
single-acting type up to the double-acting
twin-tandem type.

Fig. 6 was plotted from the results of
some tests recently made on a double-
acting tandem engine at the Flatbush
pumping station of The Flatbush Gas
Company, Brooklyn, N. Y. The engine
has cylinders 18 inches in diameter and
a stroke of 24 inches; it is used to drive
a gas pump and is rated at 335 indicated
horsepower at 175 revolutions per min-
ute. As the chart indicates, the load was
carried slightly beyond 330 brake horse-
power. The four observation points be-
low the left-hand third of the economy
curve indicate readings taken at the

.,-

35-

4,000.000

->^

eo,ooog

1 1

-ISOR.p

■

^

m.

\

^

18,000 1

1 1
'I^SR.p.m:

s,

s

^

16,000 &■

lOOR.p.m.

tr.

\

V

^

'■ 1

•■1

X<?. ! ^

°A

^

^?5

14,000 1

1 Slowbpeed \ , ^s;^^

^

rH

f

•

1

lests-^.^

I4S R\nlS^~^

^r-ot-

; J

'' 1

12,000-0

r i^"^ — -^^^

Orseon,,,'^, 'u-

L

0 2,000,000

,6^;

• ^.^

-

10,000 §.

^

!

r

I

o

j

-u

-o —

«.ooo-:

*"

^

>

1,000,000

!

1

I 1

1

ways been under the impression that it
was the best practice to leave all valves
shut for the protection of the valve seats.
S. G. Rose.

Brockville, Ont.

\\ hy the Engines Stopped

In a power plant consisting of six
14x18 three-cylinder vertical engines and
one 16x18 horizontal single-cylinder en-
gine, all of the four-stroke type and
operating on natural gas, the ignition cur-
rent is normally supplied by a motor-
generator set, and a set of battery cells
is used for starting the first engine.

At about 10 o'clock one morning, all

50 100 150 £00 250 300

Brake Horsepower
Fig. 6. Plotted from Test of Gas Pumping Engine

To Mcten '-^

The Pressure Regulator

The crosshead shoes are pivotally at-
tached to the crosshead block in order
that they may remain true with the
guides regardless of any bending of the
piston rods; this is true of both cross-
heads and the tail shoe.

In the application of the piston-rod
stuffing boxes a considerable departure
has been made from the original practice
of setting the packing-ring housings in-
side the rod guides. As may be seen in
Fig. 1, the packing-ring housings are
attached to the outside faces of the cyl-
inder heads and are, therefore, easily
accessible without disturbing the heads;
this also permits the cylinder heads to
be uniformly cored and cooled.

Ignition is effected by means of makc-
and-break igniters, electromagnetically
operated and supplied from a storage
battery which is kept charged by means
of a small dynamo driven by the engine.
An automatic cutout, operated by a
solenoid, disconnects the dynamo from
the battery when the dynamo voltage is
cither too low or too high for the stor-
age battery. In all of the double-acting
engines two igniters are provided in each
end of each cylinder and provision is
made for starting with compressed air.

The engines are also made in single-
.-icting form, both single cylinder and
tandem, snd each of the.se is made in

speeds stated, and show the influence
that reducing the speed exerts on the
friction losses.

LETTERS

Points in the Care of Oil
Engines

I have read J. S. Leese's article on the
care of oil engines, in the October
24 issue, with much pleasure and profit,
but there are three points on which I
should like more information.

(1) I can hardly see how the trouble
of an engine stopping a few minutes
?fter starting up can be laid to the igni-
tion tube not being hot enough. My ex-
perience has been that the engine will
not start at all if the tube is not hot
enough.

(21 With a properly designed bunscn
burner and tube which only allows the
n?ine to strike it in the correct place for
timing the ignition (though as a rule
an engine is provided with a timing
volve), I fail to sec how one can get the
ignition tube loo hot if one tried. I
have had quite as much trouble from
prcignition with electric igniters as with
the hot tube.

r3) Why should the exhaust valve
of the engine be left open? I have al-

of the engines stopped dead. We thought
possibly a fuse had blown on the motor
side of the motor-generator set, and at-
ttmpted to start up as usual on the bat-
tery, but could only get a few impulses,
after which the engine would stop. Upon
testing out the ignition system we found
we were getting plenty of current and a
good spark, so we investigated the gas
pressure. The pressure regulator in the
meter house indicated that the gas pres-
sure was very low, the spindle of the
regulating valve being in the full open
position. We sent for the "gas man," but
he could not suggest anything. He said
he had 18 pounds pressure on the main
line, so we figured the trouble must be
in the regulator. Upon taking out the
plug in the bottom we discovered that the
valve disk had become detached from the
stem and dropped down on its scat, there-
by shutting off' the supply of gas. Upon
taking the regulator apart it was found
that the nut which slips down over the
valve stem and screws into the valve
had come unscrewed.

The accompanying sketch clearly shows
the construction of the regulator, but no
one as yet has been able tn account for
the valve nut becoming unscrewed.

H. H Daniel

Titusville, Penn.

P O \X' E R

November 2S. 1911

Cooling Air of Buildings by
Mechanical Refrigeration

By E. F. TwEKnY

One frequently hears expressions of
surprise over the fact that the artificial
cooling of the air in dwellings, public
buildings and places of amusement is
not more general. Why is it that in mod-
ern social and industrial life there has
not been felt the necessity of maintain-
ing homes and places of business and of
pleasure at a temperature as conducive
to comfort during the heat of the sum-
mer as during the cold of the winter.

To begin with, the period during which
artificial cooling is required — at least
throughout the temperate zone — is very
much less than the time in which artificial
heating is a necessity. If it is assumed
that 70 degrees Fahrenheit is the tem-
perature which is most pleasing to the
vast majority of persons — admitting the
fact that one occasionally encounters an
irdividual who evinces a preference for
a temperature of 60 degrees Fahren-
heit or thereabouts — it may be noted,
from a glance at Fig. 1, how small that
portion of the entire year is in which
the average outside temperature is in
excess of 70 degrees Fahrenheit, and,
by comparison, how large the portion is
during which the outside temperature is
below 70 degrees Fahrenheit. The stepped
curves of Fig. 1 show the mean monthly
temperatures throughout the year of New
York City, Chicago, Portland, Me., and
New Orleans, respectively, the tempera-
tures as given being averages for a long
period of years. It may be seen that
in no month during the year does the
mean temperature of Portland, Me.,
reach 70 degrees Fahrenheit, while in
New York City and Chicago a higher
mean temperature than 70 degrees Fah-
renheit exists only during some two
months of the entire year. Even in the
case of New^ Orleans, only five months
in the year show a mean monthly tem-
perature in excess of 70 degrees Fah-
renheit.

Air cooling has already assumed com-
mercial importance in several industries,
notably in the inanufacture of chocolate
and in the operation of blast furnaces.
Before chocolate-manufacturing plants
were artificially cooled, it was difficult,
if not impossible, to continue the opera-
tion of such plants during the extremely
warm portion of the year. In the case
of blast furnaces, the air is cooled for
the purpose of removing its moisture,

thereby making it possible to reduce
slightly the amount of coke used, inas-
much as when moisture is present in the
air a small portion of the total fuel is
used in heating this moisture.

Coming to the physical considerations
involved in the cooling of air, the fact is

duct of the number of pounds of dry
air present, the specific heat of air. which
is usually taken at 0.238. and the range
of temperature through which the air is
cooled. A small additional quantity of
heat must bs removed in order to cool
the varying amount of vapor present
from its initial to its final temperature.
Ihis quantity is relatively so small —
probably averaging 2 or 3 per cent, of
the total heat abstracted in cooling the
air and removing the moisture — that it
can be practically neglected, although an
additional allowance of some 2 or 3 per
cent, is frequently made to cover this
item.

The method of air cooling now usually
employed is practically the same in prin-

80

■

New 0

- I =

■

60
50

70

H,^. - ! U-^

rie .

1'

' 1

i ; I

SO

40
30

70

1

60
50
40
30

70
60

1 1 '-..-.-,.

1 '

1 ' 1

L 1 n

r— f" ^ :

1 '

50

40
30

' 1

' 1

Jan. Feb. Mar. Apr. Moy June July Aug. Sept. Oc+. Nov. Dec.

Fig. 1. Average Monthly Temperatures

presented that air is. in reality, a mixture
of air and water vapor. When air is
warmed, this moisture is heated along
with the air, but its weight is so small
compared to that of the air that the pres-
ence of this moisture, so far as having
any effect upon the quantity of heat re-
quired, can usually be ignored. When air
is cooled, however, the moisture in the
air must be removed step by step, pro-
vided a condition of saturation is reached
— a condition always to be met with in a
practical case of air cooling. The re-
moval of this moisture in the air neces-
sitates the abstraction of an amount of
heat for every pound of vapor present
equivalent to the heat of vaporization of
water, which is, roughly, 1000 B.t.u. per
pound. In addition, a quantity of heat
must be removed from the air itself, and
this quantity is represented by the pro-

ciple as the indirect system of heating.
Air is forced by a fan through refrigerat-
ing coils, and frequently water is sprayed
over these coils as the air is passing
through them, the water thus serving to
wash the air and, at the same time, to
cool it. When ammonia is the refrigerat-
ing agent, it is usual to circulate re-
frigerated brine through the coils, but
when carbonic acid is the refrigerating
medium, direct expansion usually takes
place within these coils, thus dispensing
with the use of refrigerated brine. From
the cooling chamber the air is led through
ducts to the room or rooms to be cooled.
The quantity of air thus circulated in a
given time between given temperature
limits and from a given initial relative
humidity determines the capacity of the
refrigerating inachine.

November 28. 1911

POWER

Some idea of the amount of heat pro-
duced by a few of the more common
types of illuminants is given in the ac-
companying table, which is based upon
data compiled by various authorities.

HEAT PU'iln lED BY COMMO.N- TYPES OF
•" ir,I.l"MIXAXT

CoNStMKD
PER Hi MR

^ 1 ^

Tvpf of Illuminant

11 £!=>
f W

Tallow cuiidle

KiTosfiif oil

foal (ras. bai wing

2200
909

3.3

16 .iSOO
16 4100

16 { 4100

Oca! leas, \\>l>bacl

.50 :{ooo

6-Klower .\ern.-.t

EncIor^tKi arc lanio (6(Ki
waits) ■

o<l-watl, carbon fila-
ment incandescent
lamp

2.V\vatt, tunesten fila-
mi-nt incandescfnt
lamp

400 1 1800
2000

16 170

1

2.1 1 .so

While the values given in the table are
cnly approximate, the superiority of the
electric light as a nonheat-producing
form of illuminant is very clearly shown.
Moreover, the incandescent electric lamp
possesses the material advantage of not
consuming the oxygen of the air and of
not vitiating the air with any products of
combustion.

In order to show the application of
some of the principles which have been
enumerated above, a practical case of air
cooling, to meet certain specified condi-
tions, will be worked out in detail. We
will assume, for convenience, a large
room, 100 feet square and with a 30-foot
ceiling and e.xposed to the outside air
on all four sides. If the specifications
stipulate that the temperature of this
room shall not exceed 75 degrees Fah-
renheit when the outside temperature is
at 00 degrees Fahrenheit, it might readily
work out that the total amount of heat
entering this room through the side walls,
windows, floor and ceiling would amount
to some 200.000 B.t.u. per hour. The
following additional assumptions will be
made; The room is to accommodate a
maximum of 500 people; it is to be
lighted by 300 twenty-five-watt tung-
sten lamps, and the relative humidity
within the room is not to exceed 60 per
cent, when the relative humidity of the
outside air is 80 per cent, for the limits
of temperature as given above.

Upon the assumption that the persons
who are to occupy this room are to be
at rest, take a heat emission of 400 B.t.u.
per person per hour, which for a maxi-
mum of 50<1 people would amount to
200,000 B.t.u. per hour. Referring to the
table showing the heat given off by vari-
ous types of illuminants. take the value
of 80 B.t.u. as the amount of heat given
off per hour by a 25-watt tungsten lamp.
The total amount of heat emitted per
hour with the entire lighting installation

in use would, therefore, amount to 24,-
000 B.t.u. It thus appears that the re-
frigerating plant must be capable of re-
moving from the room under considera-
tion a total of approximately 424;0O0
B.t.u. per hour.

The next step is to select the range of
temperature through which the air shall
be allowed to warm while passing
through the room. It is desirable from a
refrigerating point of view that this tem-
perature range be as great as possible,
and thereby reduce the total quantity of
air which must be circulated, but, as
previously noted, there are certain prac-
tical limitations to such a procedure. As-
sume a temperature rise within the room
of 15 degrees, the air entering at 60 de-
grees and leaving at 75 degrees Fahren-
heit. As there will be an unavoidable
rise in temperature between the cooling
coils and the points where the cool air
enters the room, let it be assumed that
the air will leave the cooling coils at a
temperature of 55 degrees Fahrenheit.
Taking the specific heat of air as 0.238.
it will be found that approximately 120,-
000 pounds of air must be supplied per
hour to remove the total amount of heat
determined above, with a temperature
rise of 15 degrees within the room. This
would be equivalent to over five changes
of air per hour and would afford ex-
cellent ventilation for the maximum num-
ber of people which has been assumed.

The amount of moisture present for
each pound of dry air is calculated for
the assumed outside temperature of 90
degrees Fahrenheit and 80 per cent,
humidity, as may easily be done by con-
sulting a table showing the properties
of saturated air at various temperatures,
and if then a similar calculation is made
to determine the amount of moisture
present with each pound of dry air at a
temperature of 55 degrees Fahrenheit,
which is the temperature at which the
air is assumed to leave the refrigerating
coils in a saturated condition, it will be
found that approximately 15.5 pounds
of moisture must be condensed for each
1000 pounds of dry air supplied. As it
has already been found that the required
quantity of dry air is 120.000 pounds
per hour, it is evident that about 1860
pounds of moisture will be condensed
per hour, requiring an abstraction of heat
amounting, roughly, to 1,900,000 B.t.u.
per hour. Allowance must now be made
for the rise in the temperature of the
air during its passage from the refrigerat-
ing coils to the room outlets. As a 5-
degrce rise in the temperature of the air
while passing through the ducts has been
assumed, the total gain of heal from this
source will be

5 y 0.238 y 120,000 -= 143,000 H.i.u.
approximately. The total amount of heat
the refrigerating plant must be capable
of removing per hour is, therefore, as
follows:

Heat radiated through walU, win-
dows. Iloor and ceiling 200.000

Heat emitted b.v human occupants. - 200.01)0

Heal resulting from illuminants . 21.000
Heal of li(]uefactioii of vapor removed

by condensation I.HOO.OIIO

Heal gained in passage through rlucls

after leaving refrigerating coils. . . . 14;(.000

Heat between 90 and ".i" F 42.S.400

Total 2.89.5.400

The capacity of a refrigerating ma-
chine is expressed in tons of refrigera-
tion, a ton of refrigeration being equiva-
lent in cold-producing effect to the itielt-
ing of one ton of ice in 24 hours. One
pound of ice, in changing into water at
the same temperature (32 degrees Fah-
renheit I. absorbs from its surroundings
approximately 142 B.t.u.; therefore, the
melting of one ton of ice is accompanied
by an absorption of heat amounting to
284.000 B.t.u. The "ton of refrigeration."
or "ton of refrigerating effect," is, there-
fore, eauivalent to the removal of 284,-
000 B.t.u. in 24 hours, or of 12.000 B.t.u.,
roughly, in one hour. Hence, by divid-
ing the total number of B.t.u. which the
refrigerating plant must remove per hour,
as given, by 12,000, it is found that it
should have a capacity of approximately
240 tons of refrigeration. Allowing an
additional 2'j per cent, for the cooling
of the varying amount of vapor present
with the air, the required refrigerating
capacity would be about 246 tons.

One of the conditions assumed in the
foregoing problem was that the final
relative humidity within the room should
not exceed 60 per cent. For any given
temperature to which air is cooled, the
final relative humidity will depend upon
the range of temperature through which
the air is afterward allowed to warm,
assuming the air to be in a saturated
condition when it leaves the cooling coils
— a condition always to be met with in
problems of air cooling. This is due to
the fact that a given weight of air, when
leaving the cooling coils, carries with it
a definite weight of moisture, and this
weight remains constant inasmuch as the
air passes over no water and hence
has no opportunity for gaining any ad-
ditional moisture. Saturated air at 55
degrees Fahrenheit, if warmed to 75 de-
grees Fahrenheit, will have a final rela-
tive humidity of approximately SO per
cent. This is sufficiently below the limit
specified in the problem to provide for
the unavoidable increase in moisture
which would result from the people pres-
ent in the room.

The accompanying chart. Fig. 2, is re-
produced from a paper upon the subject
of air cooling read b\ W. W. Macon be-
fore the American Society of Heating
and Ventilating Engineers. It affords a
vcrv convenient method of determining
the approximate refrigerating capacity
required for a given case of air cooling
after the necessarv preliminary calcula-
tions have been made to dctenminc the
requisite volume of air to be supplied.
The chart was derived from another chart

822

POWER

November 28, 1911

showing the B.t.u. which must be re-
moved per pound of dry air tor cooling
the air and for condensing the accom-
panying vapor, the heat units per pound
of dry air being converted into tons of
refrigeration per 1000 cubic feet of air
by assuming an average value of 0.07
pound as the weight of dry air in a cubic
foot of a mixture of air and vapor. The
variation from this value is not great
for the range of temperatures and per-
centages of humidity found in an ordi-
nary case of air cooling, the actual
weights ranging from 0.0(559 for air at
102 degrees Fahrenheit and 100 per cent,
humidity, to 0.0737 pound for air at 72
degrees Fahrenheit and 50 per cent,
humidity.

To show the method of applying this
chart, it will be employed for determin-
ing the refrigerating capacity under the
conditions of the problem already worked
out. It was found that approxittiately
424,000 B.t.u. must be removed from the
room each hour, with the air entering
the room at 60 degrees and leaving it at
75 degrees Fahrenheit, a rise of 15 de-
grees. One cubic foot of a mixture of
air and vapor at a temperature of 60 de-
grees Fahrenheit with a relative humidity
of approximately 85 per cent., when
heated through 15 degrees will take up
I X 15 X 0.075 X 0.238 = 0.268 B.t.u.
The removal of 424,000 B.t.u. per hour
is equivalent to removing 7066 B.t.u. per
minute. Dividing this latter quantity by
0.268, 26,366 cubic feet per minute is
obtained as the quantity of air entering
the room. By referrring to the chart and
following out the course of the dotted
lines, it may be found that approxi-
mately 2.92 tons of refrigeration are re-
quired for cooling the air and 5.66 tons
for condensing the vapor, for each 1000
cubic feet of air supplied per minute.
The required refrigerating capacity is,
therefore,

8.58 X 26.36 = 226 tons
Increasing this amount by Z'A per cent,
gives a capacity slightly in excess of 230
tons, which is somewhat below the fig-
ure previously obtained. This is due to
the fact that in the chart the weight of
the dry air in a cubic foot of a mixture
of air and moisture is taken as 0.07
pound, whereas the actual weight of this
air, under the conditions of the problem,
is 0.075 pound. This is equivalent to a
difference of 7 per cent., which is, ap-
proximately, the percentage difference in
the refrigerating capacities as determined
by the two inethods previously given in
this article.

In conclusion, the writer will mention
certain features of interest in connection
with a few of the more important air-
cooling installations now in use in this
country. One of the most notable is
probably that of the New York Stock Ex-
change, which, at the time of its installa-
tion, was probably the largest air-cooling
problem ever undertaken. The refrigerat-

ing plant comprises three units of 150
tons capacity each. The refrigerating
capacity provided is such that a tempera-
ture of not over 75 degrees Fahrenheit
and a relative humidity not to exceed
55 per cent., shall be maintained when
the temperature of the outside air is 85
degrees Fahrenheit and the relative
humidity 85 per cent. The refrigerating
machines are of the absorption type and
it is stated that they are operated by
means of exhaust steam at a back pres-
sure of some four pounds.

The Auditorium hotel, in Chicago, is
equipped with an air-cooling system of
considerable magnitude. The total space

shop. Carbonic-acid gas is employed here
also as the refrigerating agent, the gas
expanding directly into the cooling coils.
Water is sprayed over these coils by
means of a small centrifugal pump, the
water being cooled to about 45 to 50 de-
grees Fahrenheit in passing over the
coils, while the gas within the coils is
usually expanded at a temperature of
about 20 degrees Fahrenheit. The out-
side air in being drawn through this cold
spray and through the cooling coils ex-
periences a drop in temperature of some
16 or 20 degrees, and leaves the cooling
chamber in a saturated condition, thor-
oughly washed and at a temperature

Intersect Oiaqonal Line cor-
responding to Inlfial Temperaiure
by Horizontal Line corresponding to
rinal Temperature; from the Point of
Intersection drop a Line to the Scale
to find the Number of Tons for cooling
the Air.

Find the Diagonal L ine correspond-
ing to the Weic^tof Vapor present in the
incoming Air Juppf/iintersectthis Diag-
onal by a Vertical Line corresponding to
Weight of Vapor present inthe saturat-

ed Air at final Temperature; from the Point
of Intersection run a Line horizontaUyto the
Seals to find the Number of Tons forcondens
ing the Vapoi

5 4 3 2 1

Tons of Refriqero+inq Capacity for Coolinq Aii
per 1000 Cubic Feet per Minute.

0.005 0.010 0.015 0.020 0.025 0.030
Vopor Mixed with One Pound of ■* —
Air. Pounds

Fig. 2. Chart Giving Refrigerating Capacity Required to Cool Air

cooled is approximately 500,000 cubic
feet and comprises the banquet hall, re-
ception rooms, etc. An average differ-
ence of some 14 degrees is maintained
between the temperature in these rooms
and that of the office and main corridor
during the summer season, while a dif-
ference of some 20 degrees is usually
maintained during hot weather between
the temperature within these rooms and
the temperature of the outside air. The
CO; system is employed — expansion of
the gas occurring within the cooling coils.
The CO; compressor is driven by an elec-
tric motor. It has been stated that the
cost of operating this system is approxi-
mately $20 per day, which includes the
cost of power, water and labor, but is
exclusive of interest and depreciation.

The new Blackstone hotel, in Chicago,
has an extensive air-cooling system
which takes in the main restaurant, ban-
quet hall, cafe, grill room and barber

ranging from about 60 to 65 degrees Fah-
renheit. Three separate cooling cham-
bers have been provided, each having
its own blower and connections by means
of ducts with the room or rooms which
it serves to cool. The blowers are of the
double-intake type and maintain a pres-
sure of from three-quarters to one ounce.
The ducts are made of sheet metal and
are provided with 1-inch asbestos air-
cell covering. The air enters the room
through ornamental registers located at
a distance of some 8 feet from the
floor, while the exhaust is taken from
both the floor and the ceiling in order
to promote the circulation of the air.
Rheostats automatically regulate both the
supply and the exhaust. It is claimed
that within the rooms which are equipped
with this system the average temperature
during extremely warm weather is main-
tained at least 20 degrees below the tem-
perature of the outside air.

November 28. 1911

POWER

823

Issued Weekly by the

Hill Publishing Company

JOBM A. Hill, Pre*, and Trefc.. Roil"T McKSAN,Sec*r.

505 Pearl Street. New York.

122 Sooth UlcbiCftn Boalevanl. Cliii-AStx

6 Boaverl*! Stn-cl. ly>ti<lf>li. K C
t7Dt«rdea Liudeu ;i— Bvrliu, N. W. 7.

Correspondence suitable for the col-
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ijiust be given — not necessarily for pub-
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Pay no money to solicitors or agents
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Entered as second class matter. De-
cember 20. 1910. at the post office at
New York. New York, under the Act
of March 3, 1879.

Cable address, " PonTCB." N. Y.
Business Telegraph Code.

CIRCVLATIOX STSTEilKST
Of this issue 30.000 copies arr printed,
yone sent free regularly, no returns from

eu-s companies, no back number*. Figures

re live, net circulation.

Contents pagb

city Sewage Flushing I'lant SOO

The Fusing Temperature of Coal Ash... .Sii2

Pipe Threading IMes 800

Steam Driven Air Compressor Economies 807

Confessions ol an Engineer Sii.S

l.<'Btber Piston PacKing 809

Power House Lighting S13

The Buckeye Gas Engine 817

Points Id the Care of Oil Engines 819

Why the Engines Slopped 819

fooling Air of Buildings by Mechanical

Refrigeration SiO

Editorials 82.S-824

■ 'radical I.<>tters :

Homemade r;iasH Float Xeedl" Valves
.... Adjusted the fiovernnr, ...Weld-
ing a Flange. .. .Inloresllng Belt
I>rlTP. . . .Gasket Cutler. . . . Improv-
ing Efficiency of Air Pump. .. .Gov-
ernor Repair .loh 82.'>-S27

IMu-iisKlon I^etters :

Prevent Rtnndpipe Freozing ....

Crank Pin oiler QiK-atlnno for

l>l»-usslnn. . . .poorly T>eslgned Hear-
ings. ... Vlhrnllon of the Indicator

Pencil Engine Knnrlo Value

of Engine Room ln«peetlon. .. .Im-
portant Engine Tnts . . . Englneern'

Reference Book T'slng (he Firm's

Stationery NZR-R.tl

Fntal Roller Tuhe Rlowont S3.T

Power Plant Belting

In the calculation of belting problems
there is little occasion for the use of
elaborate and perplexing formulas which
sen'e no useful purpose, but rather
mystify and puzzle those whose familiar-
ity with algebraic expressions is limited.
In the solution of belting problems, good
ji'.dgment and mechanical common sense
are the only mental requirements. Some
knowledge or experience with surface
friction is valuable but not a necessity.

In the installation of a belt-driven sys-
tem, good mechanical judgment and com-
mon sense on the part of the engineer
are of prime necessity, and each case
should be decided on its individual re-
quirements.

Probably one of the chief difficulties in
the way of understanding belt problems
is a lack of knowledge of the relation
which belts and pulleys bear to each
other. It is generally supposed that the
diameter of the pulley over which the
belt runs determines its load-carrying
capacity. But, as a matter of fact, it is
the linear velocity of the belt and it
makes no difference whether it runs
over a large or a small pulley; the tension
being the same the power transmitted
will be proportional to the speed.

Power is transmitted from a belt
through pulleys by virtue of the friction
existing between the surfaces. This fric-
tion depends on the tension and the speed
at which the belt travels, and is not di-
rectly effected by the pulley diameter. A
belt passing over a pulley at a given rate
of speed and tension will transmit a cer-
tain amount of power, and while the
speed and tension remain constant,
changes in pulley diameters will net
make any change in the power trans-
mitted.

Doubling the diameter of a pulley
doubles the surface contact, but with the
tension unchanged there will be but one-
half the pressure per unit nf surface
that there was and the frictional resist-
ance will remain the same.

Changes in pulley si-.es have been
made to increase the driving capacities of
belts which have resulted satisfactorily,
because, with the change nf pullcv diam-
eters there came an Incrcisc in the sprcd
of the belt, and this instead of the in-
creased surface contact, was the cause
of the increased transmission.

As a brick will offer the same resist-
ance to sliding, whether standing on end

or lying on the side, so will a pulley of a
given width offer the same frictional
resistance to a belt, whether of one diam-
eter or another.

It seldom happens that both pulleys
in a belt transmission are of the same
diameter, and the arc of contact varies,
and the frictional resistance is propor-
tional to the pressure per square inch
and the pulley surface covered, and the
longer the arc of contact the greater will
be the area subject to the phessure. This
being true, only the smaller of any pair of
pulleys in a transmission need be con-
sidered, for on this pulley the arc of con-
tact and consequently the total pressure
will be least. It is just as though
when the brick was turned on its
end its weight was diminished in
proportion to the reduction in its fric-
tional surface.

The power which a belt will transmit
is the product of the tension and the
speed, and the power that may be taken
is proportional to the arc of contact, be-
ing greatest for 180 degrees. For an arc
of contact of 90 degrees the power trans-
mitted is about 60 per cent, of that at
180 degrees and will increase with the
number of degrees embraced, not be-
cause of the increased surface, but be-
cause of the increased pressure per
square inch between the belt and the
pulley as the surface embraced ap-
proaches 180 degrees.

Hard and fast rules for belt capa-
cities are not possible, and there is prob-
ably more variation in the published for-
mulas of different authorities than for
any other power-plant equipment. This
may have arisen from the fact th"t the
difference between the load that a belt
may b« made to carry temporarily, and
what it should carry, is so great that dif-
ferent factors of transmission arc used
by authors with varying conceptions of
what constitutes best practice.

Among the many rational rules for
leather belling, probably the simplest is
that which says a single belt one inch
vide traveling SOO feet per minute will
transmit one horsepower. A double belt
ar the same speed will do FO per cent,
more. This rule contemplates a tension
of about 40 and fiO pounds respectively
for each inch of belt width.

tt Is somewhat approximated In an-
other which allows 70 and 4.^ square feet
of belt surface per minute per horst
power for single and doublt belts re-
spectively.

824

Hither of these rules, if followed, will
provide ample rebcrve capacity and in-
sure that the work will be done without
undue stress.

Efficiency in belting consists in getting
the largest number of horsepower-hours
transmitted for the money invested. In
some cases this may dictate a low-priced,
inferior and short-lived belt, carrying a
heavy overload with temporary construc-
tion. In others it means the best product
the market can supply, moderately loaded
and having a great reserve capacity for
temporary overloads or future increase
in requirements, and all phases of the
problem should be fully considered when
making an investment in belting.

P O U' E R

The Wage Question

Steam Consumption Guaran-
tees

It is the practice for steam-engine
builders to include in their proposals a
statement of the amount of dry steam in
pounds at the required pressure which
the engine will us.e per indicated horse-
power-hour. This statement is often
made, whether ca'led for by the pur-
chaser's specifications or not, in the hope
that the prospectixe purchaser will be
influenced by the claim of a low steam
consumption. Naturally the tendency is
to make this steam-consumption guaran-
tee as favorable as possible and such
claims are based upon the most favorable
conditions. Without actually realizing
it, the builder sometimes makes his
claims border on the extravagant and
gives such figures as are seldom realized
in actual practice.

In many cases these extravagant claims
will not often favorably influence the
well informed purchaser. Rather will he
be inclined to seriously doubt them, and
therefore weigh such a proposal but
lightly, if the figures are less than mav
be shown by actual tests of similar en-
gines working under similar conditions.
Reliable figures of this sort are not al-
wavs available.

However, the performances which may
be expected from the different types of
engines are fairly well known. When-
ever, then, a proposal is received con-
taining a guarantee of steam consump-
tion which is less than might be rea-
sonably expected under actual working
conditions, and which the builder is not
prepared to substantiate by actual and
reliable tests, the purchaser has every
reason to doubt the figures, and the re-
sult is likely to be unfavorable to the
bidder.

It is really better, therefore, for the
engine builder in such instances to use
figures which he can substantiate and to
rest his case, should others make more
favorable claims, upon his reputation for
reliahility. the successful operation of
his engine, and its proved economv.

There is something wrong when a man
who must spend years of time and study
in his effort to become a master of his
vocation is paid less per hour for the
work of his hand and brain than one
who, without mental attainments above
those of the common laborer, may master
all of the intricacies of the art of brick-
laying in three weeks.

If a young man desires to become an
engineer, he finds himself at the very
outset handicapped by educational re-'
quirements that are met in few other
callings.

At the bottom of the ladder, in the fire
room, he finds that he must understand
the elements of chemistry to burn coal
intelligently. He may become an expert
in the art of making clear, hot and
smokeless fires, but without some knowl-
edge of chemistry the why of his suc-
cess or failure is a sealed book.

While the bricklayer is well paid for
training a few muscles in a single direc-
tion, the engineer must train every fac-
ulty, for there are few arts or sciences
that do not in some form find an ex-
pression in the daily round of a real
engineer's duty.

In some States and municipalities he
is required to demonstrate that he has
had, not only the practical experience
necessary to enable him to safely operate
all types of power-plant apparatus, and
has in addition sufficient technical train-
ing to calculate its probable or pos-
sible performance under all conditions
of service.

To do this, requires more than ordinarv
mental attainments, more than common
mechanical ability and a fertility of re-
source beyond that of the followers of
any other calling. When the reward for
the service of such men is compared or
contrasted with that of the men in lines
of useful work where mastership in both
theory and practice may be had in a few
months, the conclusion must be that in-
telligent, brainy, alert and conscientious
men are at a discount as operating en-
gineers.

There is something wrong, but what?
What is the negative factor that fixes
the average engineer's houriy wage be-
low that of the digger of ditches, the hod
carrier and the truck driver?

There has been a great change for the
better since the days when the barber
competed with the doctor for the neigh-
borhood tooth pulling; but the advance
in dental science has not exceeded that
in steam engineering. The dentist is a
professional worker and the barber from
whom he evolved is nonprofessional, but
both are better paid than the engineer
whose work is as necessary to societv
and is as truly professional as that o'f
the dentist. Is it because the engineer
■s not unionized? Is it because he is
not more particular about his personal

November 28. 1911

appearance ? Is it because the employer
does not appreciate the value of his ser-
vice and regards his work as one of the
many expenses of the business that must
be kept at the lowest possible point?

Eaucation was the foundation on which
•he largest engineers' organization in
the V orid was built. Did the founders of
this great body reason from false prem-
ises when they adopted the motto "To

EAR.N .MORE, LEARN .MORE"?

Engineering Mathematics

It is surprising how many practical
men are unable to successfully apply
mathematics to the solution of simple
engineering problems. These men often
possess more than ordinary intelligence
and in the pursuit of their vocations show
a high degree of resourcefulness; yet
when confronted with a mathematical ap-
plication they are apparently helpless.

Just why this is true may at first seem
hard to explain; undoubtedly there are
several contributory causes; but one of
the main reasons will be found in the
manner in which mathematics is usually
taught. Figuratively speaking, mathe-
matical expressions are the tools for use
in the solution of certain problems and
they have a definite physical application
Without a knowledge of this application,
they are analogous to a set of machinists'
tools, each a fine instrument in itself but
utteriy useless when placed in the hands
of one who is ignorant of the purposes
for which they are intended.

Mathematics is usuallv classified as
cither pure or applied, the former deal-
ing with the abstract and the latter with
the concrete objects. The value of pure
mathematics as a means of mental train-
ing cannot be denied, but very little of
this as taught in the technical schools is
used directly in later engineering prac-
tice. Instead, it is the applied mathe-
matics that is constantly used, which,
for the most part, involves a thorough
grounding in arithmetic, and merely the
fundamentals of algebra. geometr>' and
trigonometry. In fact, verv few engi-
neering problems can be solved without
a knowledge of one or more of these
branches.

The practical man often finds, when at-
tempting to study the subject by himself,
that many of the books are not intelligible
to him. This is because most of the
books upon the subject are written as
textbooks with a view to being supple-
mented in the class room by the explana-
tions of the instructor. Unfortunately,
however, too often the latter are not best
adapted to bring out the application of
the principles involved, and confusion re-
sults.

Taught with the aid of simple, every-
day illustrations, such mathematics as
are used in the majority of engineering
problems could be grasped with very lit-
tle effort.

November 28, 1911

P O W E R

825

Homemade Glass Float
Needle \'alves

The sulphate of aluminum solution
ised for the coagulation of river water
before it passes through the sedimen-
tation basins and filters, attacks brass
and copper very readily, and one of the
most annoying and frequently occurring
petty repairs about our waterworks plant
has been the renewals of the brass float
valve, copper float and the brass dis-
charge valve of the orifice box with which

...I'j

fe

B

^

U J

Fig. I. Showing Glass Float Valve

the filter plant was equipped by the
builders.

After a few years of this annoyance
it wlis determined to remedy this in some
way. A hard-rubber float valve would
have cost S35, and not caring to spend
that much money it was decided to re-
place all of the brass and copper valves
and floats about the orifice box with
homemade glass ones.

For the float-valve stem a I. i -inch holt
was ground in the center of the bottom
of an ordinary 4-ounce acid bottle, using
a piece of brass pipe and flour of car-
borundum for the grinding, the bottle
being held in a wooden frame with guide
pieces to hold the revolving pipe cen-

P radical

information from the

man on the Job. A letter

^ood enough to print

here will be paid forr

Ideas, not mere words

wanted

tral with the axis of the bottle. A sec-
ond hole >s inch in diameter was bored
by the side of the first hole for the
passage of the sulphate solution into the

i'GlassRod Br^^sic.

Brass Plate

2 Brass Rod KlJ-i?

Brass Flange
Couptint^

Lead Pipe Conneciion to Suction of
Raw Wafer Pvmp

1 10. 2. Needle Valve in Orifice Box

orifice box after it had passed the valve
opening in the neck of the bottle, the
larger hole being used merely as a guide
for the vj-inch glass rod which was
ground into the neck of the bottle with
a short bevel and which acted as the
shutoff valve.

An ordinary spherical glass float about
7 inches in diameter, such as is some-
times found in flush tanks, was used.
The 4- ounce bottle was clamped to the
side of a wooden box which was placed
over one end of the orifice box and a
guide was placed in the orifice box to
keep the float central with the glass rod.
The top of the bottle was then connected
with the lead pipe from the solution tank,
using a short piece of 1-inch light rubber
tubing for that purpose and the trick

was done. The whole thing cost .SI. 50
and the time spent in making it was very
little. Fig. I shows the float valve in
section.

The device which was gotten up for
a needle valve for regulating the dis-
charge of sulphate solution from the ori-
fice box is shown in section in Fig. 2. It
is made out of a block of babbitt metal,
two pieces of -^4 -inch glass water-gage
tubing, a 'j-inch glass rod and a small
square of plate glass having a tapering
hole in the center, the whole being bolted
together with four brass rods taken from
an old water-column gage. The material

Fic. 3. Showing Special Joint

did not cost as much as that for the float
valve but it took longer to make on ac-
count of the machine work on the babbitt
metal. This glass needle valve has the
advantage over the brass devices or-
dinarily used in that the orifice will re-
main constant in size and will not in-

@

-^

Fir.. 4. Tool foh Forming Flange of

JoiNT

crease in diameter from the action of the
solution on the metal.

The brass unions used in connecting
the lead pipe about the sulphate-solution
tanks were also in need of constant re-
newals, so the joint illustrated in Fig. ,1
was designed, the flanges being made of
'. boiler plate bored nut with a fillet to
fit the pipe, and the flange turned on the
lead pipe by means nf the tool shown in

826

POWER

November 28, 1911

Fig. 4. The lead pipe was coupled to the
angle valve on the solution tank by
means of the same kind of flange joint,
using U-shaped bolts around the body of
the valve for bringing the flange of the
lead pipe to a joint against it.

There is a yellow deposit which ac-
cumulates in all pipes carrying sulphate
of aluminum solution that makes it nec-
essary to take them apart occasionally
for cleaning. This frequent handling and
the consequent and unavoidable binding
of the lead pipe cause it to increase in
length and to make bad connections. This
tendency was obviated by putting the
lead pipes through wrought-iron ones and
making each length not more than 12
feet long.

T. H. DeSaussure.

Milledgeville, Ga.

Adjusted the Governor

Some years ago I took charge of a
small electric-light plant containing an
Atlas engine. The man in charge re-
ported that the governor was practically
worthless.

I stood by during the first night's run
and controlled the engine as best I could
with the throttle. On the following day
I examined the governor and found the
weights set as shown at A in the sketch,

Details of the Governor

and the springs adjusted to a high ten-
sion. These two conditions required a
high speed to produce sufficient centrifu-
gal force to overcome the tension of the
springs. At a speed of from 325 to 350
revolutions per minute the weight arms
were thrown out to the limit, thus prac-
tically closing the steam ports. The en-
gine at once slowed down and when at a
speed of about 250 revolutions per min-
ute the springs would bring the weights
back to their original position with a
slam, and then the engine would race
again.

I moved the weights to the position
shown at B and relieved the tension on
the springs. These adjustments removed
all governor trouble with the engine.

R. S. Livingston.

Deweyville, Tex.

Welding a Flange
Some time ago 1 discovered that the
5-inch suction flange on a duplex pump
was cracked through on one side, and it
was necessary to operate the pump as
soon as possible. The space around the
outside of the flange would not permit a

Interesting Belt Drive

The accompanying illustration shows
a belt drive that was originally installed
to run a boiler shop. A 14x30-inch Cor-
liss engine drove an air compressor
which was arranged tandem with it. The
flywheel was divided and one 8-inch belt

1

Crack I Iron Plates

Hove THE Flange was Welded

band being put around it and I decided
to break the flange in two, opposite the
crack, and then try fusing the parts to-
gether. This I did by placing the two
broken halves on a couple of irons to
keep them level and then heating them
to a fusing heat in an ordinary black-
smith forge. When at a fusing tempera-

ran up to the line shaft and another 8-
inch belt drove a 23-kilowatt generator.
Later the demand for air and electricity
called for a change and a two-stage,
cross-compound air compressor was in-
stalled and the air compressor that was
attached to the engine was disconnected.
This left the engine with an underload

,.-New Position Pulley

.S' Belt Si

14x8° ,,, r

nywfiffl' -■-- !J

■16'Belt New Wheel, r t, J

•^ ^5 Kv/. /E0'x8'

Generator

Details of Belt Drive

ture I added a slow, steady pressure to
the solid part of the flange, thus forcing
the two broken parts together, as shown
in the illustration. It has been in use
for six months and has given entire sat-
isfaction.

H. L. Russell.
Keans Canon, Ariz.

and a 75-kilowatt generator was in-
stalled, in place of the small one. The
driven pulley on the line shaft was
moved and a new pulley was placed
alongside of the flywheel, as shown by
the dotted lines. The shop could not be
shut down long enough to turn a single
crown on the old flywheel, so the gen-

November 28. 1911

POWER

827

erator was ordered with a single high
crown and a 16-inch double belt was
put on. This has been running more
than a year and has never given a
moment's trouble. The change was
made by moving the old generator close
to the flywheel and shortening the belt.
A foundation was built for the new ma-
chine where the old one formerly stood;
and the new generator erected on it. The
switchboard was also changed without
breaking into the regular running hours
of the shop.

E. W. ASHENDEN.

Minneapolis, Minn.

Gasket Cutter

In the illustration is shown a gasket
cutter. It is made from a carpenters'
divider by cutting off one leg and drill-
ing in about 's inch with a 'x-inch drill.
The cutter is made out of the tail end

Homemade Gasket Cutter

of a nie and is fitted into the hole as
shown. The cutter is then tempered.

I have used a similar tool for many
years and would not be without it. A new
cutter can be made in a few minutes if
needed.

A. L. Johnson.

Somers, Mont

Improviii}^ Kffiiicruv of Air
Puinp

A wet-air pump connected to a surface
condenser failed to produce a high vac-
uum in the condenser within a reason-
able time when starting up, but Ihe
trouble was overcome as follows: A
hole was drilled In the top of each suc-
tion pipe between the condenser and
pump and tapped out for a '/^-inch pipe,
.lets were then made out of ''-inch
pipe, as shown at 7..

The portion of the pipe below the
thread li was turned down slightly smaller
than the diameter of the bottom of the

threads and staggered longitudinal slots
were milled in the pipe to preserve its
strength as much as possible.

The slots were milled on but one side
of the pipe and covered an angle of
about 150 degrees, as illustrated by the
drawing.

The distance X is slightly less than
the diameter of the suction pipe.

The nipples were then screwed into the
suction pipes with the jets facing the
vacuum pump, as shown in the eleva-
tion, and connected to a suitable water
supply.

A small quantity of water effectively
sealed the pump valves and caused the
vacuum to rise quickly in the condenser.

Connecting the pipe which supplied
water to the jets into the top of the
casing of the centrifugal-circulating pump
gave a very satisfactory water supply
and also proved a great help in starting

only 2 inches were broken off the end, I
decided to give it a shorter bend in order
to increase its length sufficiently to get
a bearing on the finger extending through
the fulcrum casting. This made it nec-
essary to remove the good spring on the
other side of the governor and bend it
as near like the broken one as possible.
I found two weights belonging to an-
other engine that were of the right diam-
eter but much heavier than the ones
smashed. They were drilled and tapped
for setscrews, but I needed two more. A
piece of 4iV. -inch shafting was obtained
and two more weights were made from
it. By gathering up all the pieces of the
broken weights I could find and weigh-
ing them I got an idea of the amount

Spray Nozzle in Suction Pipe

the circulating water when the pump re-
fused to pick it up.

G. B. Kamps.
South Bend. Ind.

Gdvernor Repair Job

In plants where it is necessary to keep
all the engines in continuous operation
from one week's end to the other, one is
sometimes confronted with some very
perplexing propositions. This is par-
ticularly true when it would be a matter
of a week or more before the repair
parts required could be obtained.

A few days ago the main eccentric
strap on one of the engines broke with-
out warning. The engine was making
210 revolutions per minute at the time,
and the broken part of the strap went
into the governor, breaking an auxiliary
spring. The weights on both weight arms
were smashed and moved nut nf place.

So far as the eccentric strap was con-
cerned. I had an extra part on hand, but
I had no extra auxiliary springs and as

of weight required, and by adding enough
of the smaller weights which were not
broken to the homemade heavier ones, I
was able to get within a few ounces of
the desired weight. After placing these
in position on the weight arms the en-
gine was going again in about six hours.

In another instance I had trouble in
holding the babbitt slmc on the bottom of
an old-style crosshcad. Brass shoes
were made to take the place of the
babbitt metal. It was necessary, how-
ever, to take the crosshcad out and plane
about '.■ inch off each end in order to
allow the brass shoe to fit up over the
ends and afford means of fastening them
by cap screws, as the crosshcad traveled
very close In the ends of the guides and
the original length had to be maintained
to prevent striking at their end against
the guide blocks. These brass shoes
have been running several months with
scarcely any signs of wear and with ab-
solutely no trouble.

Thomas M. Sterling.

Middlcbranch. O.

828

POWER

November 28, 1911

'

I *

Prevent Standpipe Kreczing

In reply to the question asked by a
correspondent, in the September 12 is-
sue, how to prevent a standpipe from
freezing, 1 submit a description of a
job used where the temperature is some-
times 25 degrees below zero. It has
been in use for years and has never had
a "freeze up."

The water pipe is 3 inches in diameter,
and the water in it is often at rest for
several hours at a time. The pipe is in
a double box having an air space between
the two boxes, which were made out of
I'i-inch lumber. No tar or other ma-
terial was used to make the joints air

.-

'py.-

i

'

■"'

Box Surrounding Pipe and Valve

tight, although care was taken to make
neatly fitting joints. The box is under
cover and rain cannot get at it. If it is
to be placed where rain or snow would
strike it, a couple of coats of liquid tar
or other weather-resisting material would
be necessary on the outside of the large
box.

The space between the outside of
the pipe and the inside of the sawdust
box is 4 inches. The air space between
the two boxes is 3 inches. The valve
box is made with a larger space and is
tightly packed with straw. A board pre-
vents the sawdust from falling from the
upper part of the pipe box to the valve
box. The valve handle is extended so
as to come outside of the box. as shown.
The covers are attached with screws.
J. E. Noble.

Toronto. Can.

Thomas Nicholson's query under the
above caption in the September 12 issue
recalls to mind an experience related to
me several years ago by an engineer
who had had a similar trouble.

His plant was situated in northern
Russia and the object, during the major

Comment,

criticism, suggestions
and debate upon various
articles. letters and edit-
orials which have ap-
peared in previous
issues

part of the year, was not so much to pre-
vent the water from freezing as to keep
it in a liquid state at all. The standpipe
was not so long as Mr. Nicholson's, be-
ing but 28 feet high.

This engineer was in charge of the
plant at the time the standpipe and stor-
age tank were installed, and he had the
14-inch pipe, which was constructed of
riveted-steel plates, carefully built around
with firebrick and fire-resisting cement.
A jacket made out of the sheets of dis-
carded boilers was erected around this,
leading a 3-inch annular space between
the jacket and the brick.

\ small brick stove for burning coke
was put in at the base of this arrange-
ment. The cost of the coke used figured
very small on the cost sheet and the
standpipe was successfully protected
from the effects of the cold. The coke
fire was kept going at night and during
light loads and prevented the water in

.mm
Protecting a Standpipe from Freezing

the tank at the top of the pipe from
freezing when the demand was light, as
the heated water in rising in the pipe
displaced the cold water in the tank
above.

I might suggest that baffles riveted to
the jacket might have helped to dis-
tribute and get more effect out of the
heat. They may be arranged as shown
in the sketch herewith, which shows the
idea.

John S. Leese.

Manchester. England.

Crank Pin Oiler

Daniel Ashworth's crank-pin oiler,
which was described in the issue of
October 3, is a very good one to use
where the speed of the engine is uni-
form and high enough to keep the oil
traveling toward the pin.

The high- and low-pressure crank pins
of a large Corliss engine driving a two-

¥ty^

Grease Cup Crank-pin Oiler

stage air compressor, were equipped
with similar oilers and they worked very
well while the compressor was working
ai its full capacity and speed, on the
day shift, but during the night, the air
demand being low, the air governor kept
the speed down very low; consequently
the pins would not get proper lubrica-
tion and would run dangerously hot.

The oil cup and pipe down to the
union were removed and a large grease
cup was put on, as shown in rtie accom-
panying illustration, which overcame the
heating at low speeds.

Fred L. Wagner.

Chicago, 111.

Questions for Discu.ssion

Replying to Mr. Rockwell's inquiries
in the September 12 issue, I would sug-
gest in answer to question No. 1 that
he heat a piece of pipe red hot on one
end and put the hot end in cold water;
he will then get some idea of what oc-
curs when water is put into a red-hot
boiler. The water will enter the pipe
and there will be a rush of steam from
the cold end. caused by the rapid ex-
pansion.

Regarding question No. 3, which re-
lates to a condensing engine being sud-
denly relieved of its load and attaining a
dangerous speed with the throttle closed
tight, and the condenser running, if Mr.
Rockwell has an engine which will per-

November 28, 1911

P O T F R

829

form this stunt he should feel like patting
himself on the back and saying, "Big
discovery, old man," for all plant owners
are studying economy and this looks like
a great coal-saving scheme.

C. M. Thompson.
Hurricane Isle, Me.

Poorly Designed Bearings

The October 10 issue of Po>xer con-
tains an article on poorly designed bear-
ings.

I formerly had a small fan engine, the
flywheel of which vibrated in the man-
ner shown on page 559.

sniJ

Lm

Fan Engine Bearing

When an engine having this type of
bearing is new, no trouble of this kind
will be noticed, but if the cap which holds
the shells in place becomes a little loose,
the shells will work back and forth in a
horizontal plane and some become so
worn that no amount of tightening will
stop the vibration.

The bearings should be put in good
shape with enough liners removed so
that there Is about 0.008 inch clearance
between the top shell and the shaft. A
piece of soft-lead wire laid on top of the
shaft before the lop shell is replaced and
the cap pulled down solid will do. If
the cap and shell are then removed the
thickness of the wire will show the clear-
ance.

The side of the shell in front of the
joint should then be chipped off flat, so
as to get a fairly good full bearing hori-
zontally for the plug C. -ihown in the
illustration, and equal to the full vertical
diameter of the setscrcw R.

Two holes should then be drilled and
tapped In receive the seiscrews. care be-
ing taken that the holes do not weaken
the pillow-block casting. The seiscrews
should be about the same diameter as
the studs which hold the cap down, and

the end turned or ground off down to
the bottom of the threads. The end
should fit rather loosely in the hole in
the plug so as to allow the plug to cant
slightly in case there are imperfections
in the chipping. The seiscrews with their
iamb nuts should then be screwed in
and the plugs put on their ends and set
up until they just touch the shells.

The cap should then be replaced and
screwed down tight. If the nuts are
marked where they came on the studs
when they were keyed and the lead taken,
they should be turned to these marks
and no farther or a hot bo.x will result.

After the engine is started and carry-
ing its load, the seiscrews should be set
up a little at a time, so as not to push the
shells out of line. This should be con-
tinued until they are solid and the wheel
stops wabbling.

If there is not enough stock in the
pillow-block casting to permit drilling,
two steel blocks should be made and
fitted as shown in the back of the shaft
at D. These blocks should be made with
a taper of about Vs inch to the inch.
Two holes must be drilled in the cap, and
lapped for seiscrews, which may be as
small as ' .'■ inch in diameter. After
the cap is replaced and the engine carry-
ing its load, the seiscrews are set down,
pushing the tapered blocks down and
wedging the shells. If one side starts
to warm up, slack the selscrew a little
and take up on the other side.

Charles Bennett.

Chicago, 111.

\ ihr.ition of tlie Indicator

Pencil

J. W. Taylor, in the October 31 is-
sue of Pow ER. has a very interesting arti-
cle on "Vibration of the Indicator Pencil."

lions within itself similar to the vibra-
tions of a tuning fork.

Now. a piece of tempered steel pro-
portioned and loaded like an indicator
arm will have a period of elastic vibra-
tion of more than 1000 beats per second.
Moreover, a deflection of 7?^ inch, if
considered an elastic deformation of the
arm, would mean a fiber stress of several
times the breaking point of the best
tempered steel. The important point
which seems to have been overlooked is
that the vibration in question is one of
the indicator spring itself together with
all the moving parts attached to it.

The statement is also made that "The
vibrations of the arm are set in motion by
a sharp blow produced by a rapid change
of pressure." It is not a rapid change
of pressure which causes shock, as wit-
nessed by the absence of vibration in
the compression line; in fact, there may
be no shock at all other than that due to
play in the pencil motion. The vibrations
are set in motion by the inertia of the
indicator parts which at any sharp cor-
ner in the true outline of the indicator
diagram arc unable to change their state
of rest or motion instantly, so that in
this case the pencil first lingers above
the true expansion curve, and then gain-
ing downward velocity, passes below it,
the vibration gradually dying out because
of friction in the indicator piston, etc.

I have indicated steam engines which
gave the type of diagram under discus-
sion and have had more interesting ex-
periences with the gas-engine indicator
in which the fundamental causes of vi-
bration are more accentuated by the
sharp point which occurs at the top of
the ignition line. At high speeds this
effect becomes quite prominent and the
two accompanying indicator diagrams
hear witness to the fact that the indi-
cator piston is a part of the vibrating

niACRA.ViS FROM SAME GASOLENE ENGINE

While Mr. Taylor's explanation of the
"jagged expansion line" is in the main
correct, there are certain minor respects
in which his reasoning is at fault and
which might lead a good many into error.
In speaking of the rapidity of vibra-
tion he says: "The arm is the only part
of the Indicator subject to vibration
which has anywhere near this frequency."
Again. "The frequcncv of vibration de-
pends upon the length and section of the
ann and the weight of the pencil holder."
From these statements one might infer
that the arm is subject to elastic vlbra-

system together with the pencil motion
and a piece of lead on the pencil point
if it is desired In put it there. These two
diagrams «cre both taken from the same
gasolene engine running at 500 revolu-
tions per minute, the engine carrying
.ipproximaicly the same load. The same
indicator was used but was furnished
with two sizes of piston, the smaller of
which was one- fourth the area of the
larger. There were two springs, one
registering IfiO pounds per inch in hlghi.
This spring with the large piston was
used to obtain the diagram B. showing

830

POWER

November 28, 1911

the smaller wave effect. The other spring
was of 60 pounds capacity and if used
with the quarter-size piston would give
a 240-pound pressure scale. It chanced,
however, that the small piston was
heavier than the large one. The result,
as shown by the indicator diagram A,
as would be naturally expected, was that
the heavy weight attached to the light
spring vibrated more slowly and with a
greater amplitude from the same provo-
cation than did the light weight attached
to the stiff spring.

Amos F. Mover.
Buffalo, N. Y.

Engine Knocks
I have had the same experience with
engine knocks as cited by W. A. Mills.
I found that the clearance of the piston
was not even at both ends, there being
but Js-inch clearance at the head end
cold; when heated up, a slight amount
of moisture in the clearance at the head
end caused a knock. A loose-fitting pis-
ton or exhaust valve will also cause a
knock when steam is admitted.

William Nottberg.
Kansas City, Mo.

A'alue of Engine Room
Inspection

I was very much interested in Mr.
Collins' article, "Value 'of Engine Room
Inspection," in the October 24 issue of
Power. A number of years ago, when
I was running a small plant, I would go
over everything to see if the man I re-
lieved was trying to "put" anything over
on me and also to see how much I could
find in order to "knock" on him. During
the past 10 years, however, I have been
going over everything daily, but with a
different object in view, the successful
handling of the load as it came on. It
is impossible to always leave everything
in first-class shape, but the relief should
always be told what is wrong or likely
to be.

For instance, if No. 1 main bearing is
running a little warm, tell him, or, better
still always have a pad on the desk and
put the thing down so that he can see,
and then you are sure that you have told
him. It matters not if No. 2 guide is
hot, if No. 3 condenser is dirty, if a tube
has just been lost in No. 28 boiler and
the man in the coal tower has a motor
that sparks badly and needs an elec-
trician for a few minutes. If you give
your relief warning he will get out of it
all right. If you do not, the chances
are he may have trouble and the come-
back will be bad for you.

It has been the custom in my experi-
ence for the water tenders and oilers to
change shifts about half an hour ahead
of the engineers; then they have time
,to make an inspection and report to the
engineer; thus if anything is wrong, both
the engineers know it at the same time.
The man you are relieving wants to

know these things, and he will not leave
you to get out of the trouble as best
you can.

There are always a few things I want
to do when I enter the engine room, as
find the temperature of the condensers,
how far the valves are open which sup-
ply the circulating water, so that I may
know what we have to go on each unit.
Next come the feed pumps and the
quality of coal. I also find out if there
is any extra load, due to a breakdown
in some other plant. This is important
to the water tender for a stoker cannot
be rushed like hand firing.

If oil is burned, see that there is plenty
in the supply tank. It is good practice
to find out if there is any trash in the
river, or whether much slush ice is com-
ing down, for there is nothing that will
put a plant down and out. especially if
there are two or three turbines, as trouble
with the condensers.

K. C. Jones.

Reno, Nev.

Important Engine Tests

Referring to Charles Thomas' article
in the October 17 issue, page 595, on the
subject of testing engines for leakage, 1
do not wish to be understood as criticiz-
ing any of the excellent methods he
recommends, but it occurs to me that in
case one wished to look into the subject
further, he would have to ask himself
the question, If the piston shows steam
tight on either dead center, is that a
guarantee that it is the same at all other
points of the stroke?

In reboring large cylinders and in
calipering others to see whether they
were worn materially, I have noticed
that they show the greatest wear at or
near the middle of the stroke. While
the steam ring would, if in good condi-
tion, adjust itself to this enlargement of
the bore, it stands to reason that the
leakage will be in proportion to the wear.

To get around this question, many able
engineers and erectors for the engine
builders recommend blocking the fly-
wheel at different points of the stroke
of piston, and then testing with steam as
outlined in Mr. Thomas' article.

It has occurred to me that a supply
of compressed air might be of service to
test out an engine cylinder and valves.
I have sometimes used it to test the
tightness of a globe or gate valve, and
have found that when a valve holds
compressed air well, it is not going to
leak steam to any extent. Has any reader
of Power ever tried this, and if so, with
what results?

As air does not condense, like steam,
one could pump up a tank of air. and
having ascertained that there were no
leaks from the tank or the line, close
the engine-throttle valve and connect the
air to the steam chest and to each end
of the cylinder in turn. The speed with
which the air pump had to run, or the

rapidity with which the pressure in the
tank went to zero, would be an indi-
cation of the tightness of the parts in
question.

I think the above would give a closer
approximation of leakage than in laying
out the theoretical cur\'e in the expansion
line of an indicator diagram, as described
and recommended by numerous text-
books.

L. F. Brown.

Winston-Salem, N. C.

Engineers' Reference Book

1 am using an engineering reference
book having every feature mentioned by
Phil Lighte in the October 17 number.

About four years ago I started to de-
velop an engineering reference book
which would not be too large for
the pocket, and would allow the re-
moval and addition of pages with ease.
I first bought a so called ring binder with
'4 -inch rings and a 3x5-inch page bound
on the side. I soon found this would
not do as the pages wore rapidly in the
rings so that they would come out and
I had a really "loose" leaf book.

The one I am using at the present
time takes a 4x7-inch sheet bound on the
end with a soft-brass rod that holds the
pages firmly without any wear. It is
made by Asa L. Shipman's Sons, of New
York, and is known as their No. 300
binder. It has a capacity of about 1 inch
of paper.

The paper I use is called glazed onion
skin; it comes in S'.^xll-inch sheets
and any printer will cut it to fit the book
for a nominal charge. This paper is very
strong, will stand hard service, is not
easily soiled and 500 sheets occupy a
space of only -"^s of an inch. At first I
wrote on the pages with pen and ink and
found that wherever the fingers touched
the paper the ink would blur; at the pres-
ent time all the pages are written on a
typewri'er.

In arranging the pages in the book dif-
ferent subjects may be grouped so that
additions may be made without disturb-
ing the arrangement. For instance, boil-
ers, page 200, dimensions of a return-
tubular setting, page 210, heating surface
of return-tubular boilers with different
tube spacings; any additional pages on
dimensions can be added and numbers
given up to 209; then a letter should be
added as 208A or 209B. In this way an
index can be arranged which will not
have to be changed much as the additions
are made.

Some of the subjects covered in my
book are, areas of circles, alloys, belt
formulas, beams, boilers, coal analysis,
combustion, condensers, chemicals, col-
umns, controllers, conduit-wiring data,
and all the way down the line to water,
weight of, at various temperatures, wind
pressure, wrenches, etc.

A little careful thought in arranging
the index will make it easy to find any-

November 28, 1911

P O ■«' E R

831

thing wanted; for instance, under C,
Conduit-wiring data and under W, Wiring
data, conduit.

This book can be easily carried in the
hip pocket and when you want to settle
an argument it is handy to have the
■ "dope."

I have often thought that some ar-
rangement could be made with the large
advertisers to issue sheets of this kind
and use the margin or back of the paper
for their advertisement.

R. J. Rivers.

Minneapolis. Minn.

In Power of October 17, Phil Lighte
asks for a few ideas on the above sub-
ject. The result of some years of ex-
perience is offered herewith.

A properly kept engineers' notebook
soon becomes an exceedingly useful tool
and the time devoted to it will bear good
interest. As the result of his own and
others' mistakes, the writer's experience
is that the notebook should be of the
loose-leaf variety. Do not use staples
or other fastening devices for holding
any kind of sheets together, in connec-
tion with some stiff paper cover or "com-
mon-sense" binder. This may do for
things of odd size, for photos, blueprints,
etc., but for a notebook it takes too much
time to fit in or remove sheets. Pro-
cure a standard loose-leaf binder, with
a good leather cover, preferably flexible;
front and back united. Select a binder
with rings, as the book will lie open per-
fectly flat, a feature possible only with
ring books. If the binder is not crowded
with too many sheets, has a strong card
front and back and is handled with care,
it will give satisfaction.

Sheets 6x9 inches are best because this
is the size of most publications, and
often one desires to insert valuable tables
from these papers or from catalogs.
Likewise, there appear full-page dia-
grams in such 9xl2-inch periodicals as
Po«ER, American Machinist, which, if
folded once, and the bottom margin
sheared off, can readily be inserted in
the notebook. For one's own charts or
drawings and tabular matter a 6x9-inch
page seems small enough when a fair-
sized volume is expected. The writer
has in use one loose-leaf book containing
2 inches of sheets, but prefers his books
having I-inch rings, supposed to hold 100
sheets; half-inch rings would be too small.
Loose-leaf manufacturers make binders
up to Sii'xBi-i inches in size with six
rings, and the larger sizes with but three
rings. They also usually omit to pro-
vide an envelop or pocket for holding
indicator diagrams, personal cards,
stamps, etc.

To carry the book in the pocket, flx9
inches will be too large, unless one is
satisfied to carry in a 4x10 envelop only
a group of the sheets temporarily re-
moved from the binder. The fix9-inch
binders are not listed in the "I — P"
series, but come under the name of

Walker's book. Cooke & Cobb Company,
Brooklyn, N. Y., are the only makers of
this size I know of.

The paper should be white, of good
quality, strong yet thin, and preferably
without a watermark, which shows when
the sheets are blueprinted. Quadrille rul-
ing of faint tint, with squares ^'2 to i)-.
inch are most- convenient for technical
work, writing on each line, on one side
of the paper only. For legibility, all
notes should be written with either water-
proof India ink or with Higgins' eternal
ink, which is sufficiently black to yield
good blueprints and yet liquid enough
to flow in a fountain pen. It is a good
plan to put aside a blueprint of each
sheet, so that a loss of the book would
not be felt too keenly. The paper ought
to be smooth and tested as to whether
it takes the pen readily, as rough paper
may be good for lead pencil only.

After experimenting with numerical in-
dices, the alphabetical index was found
to be simpler, quicker and more eco-
nomical in space. A set of guide sheets,
leather tabbed, from A to Z, can be had
with the binder.

In the arrangement of contents, one
must adopt a plan of his own, as strict
rules will not be followed. One man is
thinking of "engines, steam," the other
of "steam engines"; the first puts his
notes on a sheet back of letter E, the
second writes under S. When taking
notes of steam, gas and oil engines it is
preferred to keep them separately under
S, G and O. When in doubt as to whether
data on air compressors belong under
A or C, simply turn to either and see
how it was done before. Maintain the
same location and soon the place adopted
will be fixed in the memory. Do not
attempt to follow within a 1-inch book
the elaborate subdividing of subjects
practised in large libraries, for it is
wasteful in space and time. There arc
not likely to be more than two dozen
sheets under S, and as these are page
numbered consecutively 81, S2, or S1.1,
SI. 2, or SI a. S2a, etc.. so as to assist
in mamtaining their chronological order,
and as the various headings arc neatly
underlined, any particular memoranda
can be found quickly. A brief cross
reference, such as "see S18," on page
S3, for instance, connects new notes with
older ones on the same subject. This
will avoid using a lot of sheets with
only a few lines written on each. It is
only necessary to place the matter where
it naturally would be diverted by a key-
word if one had been assigned.

As to the importance of dating, men
will preserve a clipping from some pub-
lication hut neglect to write on it the
name and full date; draftsmen will pre-
pare plans and leave off the date; others
merely 'tatc the month and day. not the
year Always indicate the source of the
information and the date somewhere on
every sheet.

Some employers object to having any
record of experience, observations, prac-
tice, tests or prices in private custody,
or they will claim ownership to the book
and all its contents, even to items foreign
to their business, if they have been en-
tered during working hours. The em-
ployer had best be asked at the outset
what his pleasure would be if it should
ever come to a severing of connections;
each man must decide for himself. For
a private book one should not appropriate
binders and paper not personally paid
for. The owner's name and address
should appear in front of the book.

Do not use a loose-leaf book as a
receptacle for old letters, sketches, etc.,
converting it into a wallet. Use a letter-
filing case, as otherwise the note sheets
will be forced off the rings. Keep only
a few blank sheets in reserve in the
back, and preserve the stock of clean
sheets elsewhere until required.

Once the excellent habit of taking
notes has been acquired, one book will
soon be tilled up, when a second one of
exactly the same size can be started,
either distributing the one alphabet over
the two books, or, what is usually bet-
ter, keep in the one book all matter
which is referred to most frequently, or
which logically belongs together.

Charles H. Herter.

New York Citv.

Using the Firm's St;xtionery

In the October 24 issue, Paul Montague
writes of an engineer's discouraging ex-
perience in using the firm's stationery
when writing for catalogs, adding that
he has often wondered how many cata-
logs never come and how many manu-
facturers miss sales to the engineers who
use the firm's stationery.

Unless otherwise stated in the letter,
the advertisers will usually send their
catalogs and literature to the address
on the letterhead. Nearly all the cata-
logs which come to the firm's office which
do not directiv interest arc dumped
into the waste basket and the engineer
never gets them. I have found this out
through personal experience when going
to the office and seeing a catalog in the
waste basket which I had written for on
the firm's stationery.

I still use the firm's letterhead in
writing for catalogs and information from
advertisers, for it gives a letter an air of
responsibility and the advertiser will
quote prices more readily than if the let-
ter were written on plain paper. I al-
ways stale my position and whether I
have the authority to buy. and to address
me personally.

Since adopting this method of writing.
I usually get very courteous treatment
from advertisers.

M. W. IITZ.

Minster, O.

POWER

November 28, 1911

The distance between two pulley cen-
ters is 30 feet. One is 18 feet and the
other 18 inches in diameter; how may
the length of the belt be found?

R. F. H.

Subtract the radius of the smaller pul-
ley from the radius of the larger and
divide the difference by the distance be-
tween the shaft centers.

In a table of sines find the angle whose
sine corresponds to the above quotient;
call this angle A. Divide this angle by
90 and call this result B.

To result 6 add 1 and multiply the
sum by the radius of the larger pulley
and by 3.1416. Call this product I.

Subtract B from 1 and multiply the
remainder by the radius of the smaller
pulley and by 3.1416. Call this product
II.

Multiply the distance between the
shaft centers by 2 and by the cosine of
the angle A. Call this product III.

Add products I, II and III together
and the sum will be the length of the
belt. Applying this rule will give 95.56
as the length of the belt requir.ed to fit
the conditions of the problem. The for-
mula for the correct length of a belt is

J (f coi. a
in which

/? = Radius of the larger pulley;
r= Radius of the smaller pulley;
d -=. Distance between the centers of
the pulleys;

a = Angle whose sme is — -, — .

Tables of sines and cosines are contained
in all engineers' reference books.

De/iiH'trd Power, Li?ie Re-
sistance a?id Current

Knowing the power delivered at the
end of a line, the resistance of the line
and the voltage at the generator end,
can I calculate the line current and the
drop ?

G. A. H.

You can if you have the patience. The
process is as follows:

Divide the square of the generator
voltage by four times the square of the
line resistance; divide the delivered
power by the line resistance and sub-
tract the quotient from the first quotient
of squares; take the square root of the
result and subtract that from the quotient

of generator voltage divided by twice
the line resistance. The final result will
be the line current. Written as a for-
mula:

Volts
■ X A'ei

i HI rent

In this formula,

Volts = Generator voltage;

/?es. ^ Line resistance;

Watts = Delivered power.

Example:

( Irnerator voltagi; = oHi)
Line resistance = h ohm

Delivered power = 2:i.7ij() watts

Ctirrent =

500

•Ni(T/

Multiply line current by line resistance
to get the drop.

Hec7t U/iifs 1)1 Coal and
Natural Gas

How are the B.t.u. in coal, natural gas
and other fuels found?

H. L. S.

The number of B.t.u. per pound of
coal or other fuel is found by burning a
known weight of the fuel to be tested
in a calorimeter. The heat generated is
absorbed by a known weight of water,
the rise in temperature of which is a
measure of the heat generated. Such
calorimeters were described in Power
for September, 1905, and the articles
have been reprinted in a book entitled
"Engine Room Chemistry," by Dr.
Augustus H. Gill.

The heat value can be computed if a
chemical analysis of the coal is avail-
able as follows:

Divide the fraction of one pound
which consists of oxygen by 8 and sub-
tract the quotient from the fraction of a
pound which consists of hydrogen. Multi-
ply the difference by 4.28 and add to
the product the fraction of a pound
which consists of carbon. Multiply the
sum by 14,500 and the product will be
the number of B.t.u. in a pound of the
fuel.

What is water hammer and its prob-
able cause?

E. L. L.

It is caused by a plug of water getting
into rapid movement in the pipe and
bringing up against a dead end, a tee or
elbow, or something which suddenly ar-
rests its motion. If a plug forms so as
to cut off the steam on the far side of
it, the steam on that side will condense,
making a vacuum or reduced pressure on
one end, while the boiler pressure is on
the other, so that the plug gets into very
rapid motion and the hammering effect
is often sufficient to rupture a fitting.

Filling Pits in Commutator Bars

The commutator of a 300-kilowatt gen-
erator has a small pit between the com-
mutator bars. How may it be satisfac-
torily filled ?

C. D. B.

A common practice is to fill such a
pit with a paste made of plaster of paris
and pure orange shellac. If the pit is
deep, fill it nearly to the surface with
dry plaster of paris and apply the paste
on top. A better filler is made of powdered
asbestos, mixed with silicate of soda or
water glass to the consistency of a stiff
paste.

Heating Surface of Corrugatea
Flue

How is the heating surface of a cor-
rugated flue calculated?

H. S. C.

To find the surface of a corrugated flue
multiply the average diameter, that is,
one-half the sum of the larger and
smaller diameters, by the length and by
4.93, all dimensions to be in feet. The
heating surface will be that portion of
the flue above the level of the grates.

Vire FjXtinguisher Formula

Please give me a formula for a good
and cheap liquid fire extinguisher.

H. S. R.

There are a great many formulas for
n'aking liquid fire extinguishers. One
which is perhaps as good and as cheap
as any other consists of 2 pounds of
common salt. 10 pounds of chloride of
ammonia and 6 pounds of water. This
is thoroughly mixed and sealed in thin
bottles, to be thrown into the base of
the fire.

November 28. 1911

POWER

833

Fatal Boiler Tube Blowout

On November 16, at 3 a.m.. in a dredge
used on the barge-canal construction near
Cayuga, N. Y., one of the tubes of a
400-horsepower boiler burst, scalding to
death four men by the escaping steam.
The dredge was equipped with two boil-
ers of the same size and kind, Babcock
& Wilcox marine type, the one which
failed being located on the starboard side.
They had been running continuously
night and day and under full evaporation,
at the time of the accident. A new shift
had gone on duty, consisting of two fire-
men, Edward Whitlock and James Dal-
ton, of Seneca Falls. According to the
reports of the survivors of the crew of
the dredge, everything had been going
smoothly, when, without warning, one of
the tubes of the starboard boiler gave
way just as Dalton was in the act of fir-
ing. The outrushing steam blew the coal
bed into the boiler room, knocking down
Dalton and covering him with ashes and
live coal. There was no time for Whit-
lock to escape as the boiler room was
instantly flooded with steam. The room
was at the time tightly closed on ac-
count of the severity of the weather. The
two other men who were killed were Nor-
wegian employees of the dredge con-
tractor's company, who had stepped into
the boiler room only a few minutes be-
fore to get from its warmth a brief respite
from the weather. The engineer, operator
and oiler, who were elsewhere engaged
on the dredge, were not injured, nor was
any further damage done.

The Seneca Falls coroner conducted a
preliminary investigation into the causes
of the accident the morning it occurred,
after which the contracting company
adopted the policy of refusing outsiders
the privilege of examining the ruptured
boiler. Before this time, however, it had
been seen by the reporter of a local
newspaper and by numerous employees
of the company. From these the fol-
lowing facts have been received and au-
thenticated:

The tube which burst was one at the
end of the lowest row. The fracture
was as shown by Fig. I, and was on the
under side of the tube about 6 inches
from the bridgewall. The longitudinal
fracture was about 6 inches long, and
the transverse about 4 inches long. An-
other tube at a point near the fracture
appeared to be slightly blistered.

The boilers had been in use three
years. They operated at \1^ pounds
gage, and (he pop safety valve was set
to blow at 200 pounds. The feed water
was drawn from the Seneca river, which
is somewhat muddy and contains a small
amount of lime. A filtration system was
used to keep the make-up and the re-
turn from the condensers clean.

The boilers were overhauled by the
company the latter part of last September
ind part at the brick setting around the
furnace of the starboard boiler replaced.

They were passed upon by an insurance-
company inspector a few weeks later. The
story is current that one of the inspectors
made an examination only of the port
boiler, the one which did not fail. There
was a fire in the starboard boiler at the
time so he merely "looked it over" and
passed them both on the assumption that
if one was all right, the other, being
just like it, was in equally good condi-
tion.

F.mployees of the company say that
for some time past the boilers were
forced. It is fairly well established that
some of the tubes leaked. A neighbor-
ing resident told the writer that the fire-
man, Whitlock, declared a short time ago
he would give up his job "next week" —
he was afraid of the leaky tubes. It
was admitted by the foreman of the sec-
tion of the barge canal where the dredge
was in operation that there were leaky
tubes. "But," he said, "the leaky tubes
were in the port boiler."

In analyzing the cause of the accident,
one is first struck by the peculiar nature
of the fracture shown in Fig. I. If it had
been caused by overheating it would

Fic. 1.

Fic. 2.

very likely have been like Fig. 2. A
transverse fracture, if secondary in se-
quence to a longitudinal one, would be
expected to be at the middle of the first
one, since there the maximum bending
occurs to cause a cross tearing. That
the transverse opening is at one end of
the longitudinal suggests that it occurred
first, the force of the outpouring steam
then tearing the metal lengthwise from
this slit. This would indicate either de-
fective material or an overstrain pro-
duced mechanically.

The possible causes are :

First. Defective material in boiler tube.

Second. Material weakened by pitting
or corrosion.

Third. Material weakened by overheat-
ing due to low water or forcing.

The first cause seems likely from the
character of the fracture. On the other
hand, the boilers were worked three
vears. so that any inherent defect of ma-
terial would have probably shown be-
fore. The reputation of the boiler manu-
facturers, also, is agaiitst this theory.
But. of course, defective material may
appear in the best of products.

The effect of possible contaminated
feed water can be ascertained only after
examination of the ruptured boiler. In
view of the recent overhauling and care
in filtering the feed water, this explana-
tion seems unlikely. The peculiar trans-
verse break in the tube, however, may
be due to some such cause.

It was said that the water column
showed normal level at the time of the ac-
cident. This may have been and yet, of
course, there may have existed low water
in the boiler. A change of shift makes
this possibility more likely. The boiler
that gave way was in parallel with the
port boiler at the time; if overheating due
to low water caused the break, then the
port boiler furnished the steam that did
the damage. Nothing can be concluded
as to this without examination of the
broken tube. Forcing the boilers con-
tinuously, combined with some scale, may
have caused the blowout. The boilers
were undoubtedly forced, but, again, the
effect can only be judged after physical
examination.

The coroner's inquest, which will prob-
ably take place within a week, will un-
doubtedly bring some light upon the
causes of the accident.

An instance of pathetic heroism was
shown by the fireman. Whitlock. He re-
covered sufficiently to regain his feet.
When the doctor from Cayuga attempted
to benefit him, he was met with the
words. "I'm too far gone — do what you
can for the others." All four sufferers
died within four hours, despite help.

Large Hydroelectric Power

Project in Northern

California

The Northern California Power Com-
pany, of San Francisco, has inaugurated
one of the largest electrical enterprises
yet attempted in California on the "Big
Bend" of the Pitt river, in Shasta county.
The project has been contemplated since
September, 1902, when the original
notice of an appropriation of 2.^0.000
miner's inches of water was filed by the
company. With definite plans formu-
lated and surveys completed, articles
have been recorded specifying a change
in diversion of the water as first made
to a point about I '/■ miles further down
the stream, thus affording the develop-
ment of maximum power afforded.

A dam will be constructed across the
river at this point 120 feet long and 7
feel above the low-water level. By such
impounding the flow will be diverted intn
ditches and tunnels for a total distance
of .Si, miles to about I mile below the
Big Bend hot springs, where the power
plant is to be located, ft is estimated
that there will be 4 miles of open ditch,
the remainder of the distance to comprise
five tunnels, the longest being flOtVi feet.
These latter will be 24 feet wide by ap

834

proximately 26 feet high, thus pemiitting
the boring to be executed by steam
shovels, and offering a distinct departure
from usual practice. At the outlet the
fall of the water will be close to 15 feet,
with a width of 32 feet and 50 feet at
bottom and top respectively.

The power plant will have a total gen-
erating capacity of about 90,000 kilo-
watts, and with its diversion dam, pipe
lines and flumes will represent an in-
vestment of ,S4,000,000. The power de-
veloped will be transmitted in three cir-
cuits on steel towers, traversing the en-
tire northern section of the State, and
tying in the plant with the company's
other generating stations. The transmis-
sion system is estimated to cost 510,000
per mile.

Power for construction purposes will
be delivered from the company's Kilarc
power house and all machinery and sup-
plies will be hauled by team from Red-
ding by way of Ingot and Montgomery
creek, a distance of nearly 70 miles.
Manager E. V. D. Johnson estimates that
it will require two years to complete the
entire project.

POWER

Morrisville offers free sites and ex-
empts from taxation those industries
which will fmd the town suited to their
needs.

November 28, 1911

Municipal Plant Makes
Money

Morrisville, Vt., a town of 2700 in-
habitants, owns an electric plant which
is run at a profit, and is offering power
to the local industries at S20 a horse-
power per year.

More than 20 years ago, according to
the daily press, municipal ownership was
obtained by the purchase of a small
private water system, and the authorities
were soon able to reduce the price of
water and raise the standard of service.
In 1895 a municipal lighting plant was
installed and the water system was ex-
tended. The plant cost about S25.000.
«-hich, added to the indebtedness incurred
for the water system, made the total
.V-)8,000. This was continued until 1906,
the income from the plants paying the
interest, repairs and upkeep.

Anticipating future needs, the commis-
sioners bought part of the power rights
of a manufacturing plant at Cadv's falls
and a concrete dam 1100 feet above the
old dam was constructed which increased
the head from 17 to 40 feet. The new
structure was 330 feet long, 20 feet
wide, had a shore line of five miles and
developed several hundred horsepower

Approximately, the dam and its equip-
ment cost 870,000, making the cost of the
two systems .Si 68,559.82.

The plant furnishes electrical energy
for 8000 incandescent lamps and power
>s supplied to many small manufacturing
Plants. The authorities have contracted
-to furnish power to the Waterbury &
Stowe electric-railroad companv at half
the cost that company hitherto paid

Annual Meeting of Me-
chanical Engineers

The annual meeting of the American
Society of Mechanical Engineers will be
held as usual in the Engineering So-
cieties building. New York City, from
December 5 to 8.

Some noteworthy papers have been se-
cured by the committee on meetings, and
an important feature this year will be
contributions by three of the first sub-
committees appointed by the committee
on meetings, those on textiles, cement
manufacture and machine-shop practice.
One session is to be devoted to foundry-
practice, another to steam-boiler perform-
ance. The gas-power section will as usual
have a session, at which oil engines, at
present a subject of so much importance,
will be discussed.

The program of entertainment, as ar-
ranged by the committee on meetings,
contains many interesting features, among
which will be an inspection of the SS.
"Olympic," visits to the Navy Yard, Bush
Terminal buildings and other points of
interest.

Semi Annual Meeting of
Ohio Engineers

The Ohio Society of Mechanical, Elec-
trical and Steam Engineers held its twenty-
fourth meeting and celebrated the tenth
anniversary of its organization at Canton
O., the city of its birth, on November
I' and 18. The meeting was well at-
tended and full of interest.

Only two formal papers were pre-
sented, one upon "Superheated Steam,"
by Prof E. A. Hitchcock, of the Ohio
State University, and one upon "The
fusing Temperature of Coal Ash in Its
Relation to Rate of Combustion," bv E
G. Bailey, mechanical engineer of' the
Fuel Testing Company, of Boston, Mass.
to «n/"7'l'""'^' appears on pages 802
to 806 of the present issue and that of
Professor Hitchcock's will follow shonly
Visits were made to the Dueber-Hamp-
den Watch Company and to the Forest
stations of the Electric Light and Railway
Company. The officers elected for the
following year are: President, E. M
Adams, Akron; vice-president. Prof e'
A Hitchcock, Columbus; managers, for
three years, James H. McConnaughv
Varren:W. F.Hubbell, Wauseon;nfan-
ager for one year, to fill the vacancy
caused by the election of Mr. Adams as
president. ^X'illiam C McCracken, Colum-

Pif^K o '"' '""*'"S ^^•'■" "e held at

Pmsburg, Penn., on May 16. 17 and IS
The society has maintained its member-
ship of some 270. notwithstanding the
v.Rorous scaling down of the delinquent

OBITUARY

George W. Hebard. acting vice-presi-
dent of the Westinghouse Electric and
Manufacturing Company, died at his
home in New York City on Friday, No-
vember 17. Mr. Hebard was bom in
Barre Center, Olean county. New York,
in 1845, and was, therefore, 66 years
of age. He had been in poor health for
some time previous to his death.

Besides his active participation in his
chosen profession, Mr. Hebard was also
very active in social, religious and phil-
anthropic work in New York. He was a
member of the Union League, The Law-
yers, The Engineers and several other
clubs.

Mr. Hebard leaves, residing in New
York, a wife and two children; Charles

George W. Hebard

R-, engaged in the cotton business-
Arthur, engaged in the ammunition busi-
ness, m which his father was engaged
prior to entering the electrical profes-
sion.

Mr. Hebard was sole executor of the
Marcellus Hartley estate, which owned
the Union Metallic Cartridge Company
and the Remington Arms Companv; all
of which he settled in a most satisfactory
manner to all concerned.

He was identified with the early his-
tory of the manufacture of electrical ap-
paratus, becoming president of the United
States Electric Lighting Companv of
Newark, in 1882. and had associated with
him, as directors, Marcellus Hartley
Anson Phelps Stokes, Charles R. Flint'
Henr>- B. Hyde. Charles F. Brooker.'
Leonard Curtis, and other well known
men. Mr. Hebard was connected with
the early historj- of the generation and
d.stnbution of electric lighting in New

November 28. 191 1

POWER

835

York City as a director and stockholder
of the United States lUuminatir.g Com-
pany. In this position he had to do with
the equipment of the Weston lighting
system on Brooklyn Bridge, pans of
which are still in service. Later, as
president of the United Electric Light
and Power Company, he was closely af-
filiated with the introduction of the West-
inghouse alternating-current system in
New York City by means of the over-
head system. He was active later on in
the change of the distribution system
from the overhead to underground. At
the time the United States company was
taken over by the Westinghouse com-
pany, Mr. Hebard was president, and in
the reorganization was made vice-presi-
dent of the Westinghouse company; and,
in 1888, when this company took over the
Sawyer-Man company, Mr. Hebard was
given charge of the newly acquired or-
ganization.

The death of Mr. Hebard is the third
one to occur in the last few months
among the higher officials of the West-
inghouse Electric and Manufacturing
Company residing in New York; the
others being Edward St. John, treasurer,
and Robert Mather, chairman of the
board of directors.

PERSONAL

Howard B. Clark, consulting engineer,
of New York City, resigned as member
of the firm of Flaherty & Clark on June
I and is now Eastern representative for
the McNaull-Boiler Manufacturing Com-
pany, of Toledo. O.. a manufacturer of
water-tube boilers.

Jacques Abady. a director of the Eng-
lish firm of Alexander Wright & Co., Ltd.,
engineers and manufacturers of measure-
ment and control apparatus, sailed for
London via Quebec, on November 17, after
a two weeks' visit to Alexander Wright
& Co.'s American branch, the Precision
Instrument Company, of Detroit. Mr.
Abady Is one of the co-inventors of the
SImmance-Abady combustion recorder,
Simmance-Abady vacuum and pressure
gages and other apparatus for testing
various conditions of steam, gas, water
and air. His visit was partly with the
object of discussing several new inven-
tions, which have passed the expein-
mental stage and which will shortly be
on the market for general use In steam
and gas plants.

Bruce W. Benedict, for several years
In the motive-power department of the
Atchison, Topcka & Santa Fe Railway,
has been appointed director of the shop
laboratories in the department of me-
chanical engineering at the University
of Illinois. Mr. Benedict was graduated
from the University oT Nebraska with
the class of 1901. He served an ap-
prenticeship on the Chicago, Burlington
A Quincy Railroad prior to entering col-
Icpe. and after graduating he occupied

successively on the same railroad the
following positions: machinist, assistant
in testing laboratory, assistant road fore-
man of engines, road foreman of en-
gines, general foreman of locomotive and
car repair, and mechanical inspector.
He left the Chicago, Burlington & Quincy
Rai'road Company to become an editor
of the i\ailway Master Mechanic, of Chi-
cago, a position which he held for two
years. Leaving Chicago, he became super-
visor of schedules on the Atchison,
Topeka & Santa Fe Railway, and still
later bonus supervisor on the same road,
which position he will give up before the
first of the year to assume the duties
at the University of Illinois.

NEW PUBLICATIONS

Rail\x AV Shop Kinks. Compiled by Roy
V. Wright. Published by Railway
Age-Gazette, New York. Two hun-
dred and ninety pages, 9x12 inches;
803 illustrations. Price, S2.
This work was compiled under the
direction of a committee of the Interna-
tional Railway General Foremen's As-
sociation from the pages of the Railway
Age-Gazette and contains descriptions of
a large number of shop kinks or methods
of doing many kinds of locomotive- and
car-repair work in railway-repair shops
in all parts of North America.

The work is profusely illustrated with
both line cuts and halftones. Is com-
pletely Indexed and contains a wealth of
valuable information for the practical
railwav mechanic.

Hendricks' Com.mercial Register of
THE United States for Buyers and
Sellers; twentieth annual edition.
Published by Samuel E. Hendricks
Company, New York City. Price,
express charges prepaid, SIO.
The 1911 edition of the widely known
"Register" contains over 350.000 names
and addresses and upward of 45,000
business classifications, and is Indispens-
able as a buyers' reference for archi-
tects, engineers, contractors, manufac-
turers, jobbers, retailers, exporters, pur-
chasing agents and for railroads, ma-
chine shops, foundries, mills, factories,
mines and also for mailing purposes.

An important change has been made
in the system of Indexing the contents.
In the previous editions the numbers
following the classifications referred the
inquirer to the page number on which
the article was classified, while the sys-
tem adopted for Indexing the contents of
this edition is so numbered that they
refer direct to the classification; conse-
quently the page numbers have no con-
nection with the numbers used In the in-
dex of contents. TTiis system greatly
simplincs the location of the manufac-
turers of any article listed in the book.
It contains 1420 pages and is sub-
stantially bound.

The Bureau of Mines, at Washington,
D. C, announces the following new pub-
lications: Bulletin 13. A resume of pro-
ducer-gas investigations, by R. H. Fer-
nald and C. D. Smith; 378 pages, 12
plates. Miners' Circular 5. Electrical
accidents in mines; their prevention and
treatment, by H. H. Clark. The reprints
are: Bulletin 24. Binders for coal briquets,
by J. E. Mills; 56 pages. Reprint of
United States Geological Survey Bulletin
343. Copies will not be sent to persons
who received Bulletin 343. Bulletin 28.
Experimental work conducted in the
chemical laboratory of the United States
fuel-testing plant, St. Louis. Alo., January
1, 1905, to July 31, 190(5. Reprint of
United States Geological Survey Bulletin
323. Copies will not be sent to persons
who received Bulletin 323. Bulletin 27.
Tests of coal and briquets as fuel for
house-heating boilers, by D. T. Randall;
45 pages, 3 plates. Reprint of United
States Geological Survey Bulletin 366.
Copies will not be sent to persons who
received Bulletin 366. Bulletin 35. The
utilization of fuel in locomotive practice,
by W. F. M. Goss; 28 pages. Reprint of
United States Geological Survey Bulletin
402. Copies will not be sent to persons
who received Bulletin 402.

The Bureau of Mines has copies of
these publications for free distribution,
but cannot give more than one copy of
the same bulletin to one person. Re-
quests for all papers cannot be granted
without satisfactory reason. In asking
for publications they should be ordered
by number and title, and all applications
should be addressed to the director of
the Bureau of Alines, Washington, D. C.

In a carefully prepared and tastefully
gotten up booklet entitled "The Whole
Kewanee Family," the National Tube
Company, of Pittsburg, Penn., has in-
cluded all the "Kewanee" specialties
manufactured at its Kewanee works.

As a constant reminder of their call
and of the Kewanee union, the company's
specialty agents, when visiting the engi-
neers and other consumers, are leaving
a handsome nickeled "life-size" union in
paper-weight form.

While the paper weight has been sent
on written request from members at-
tending the National Association of Sta-
tionary Engineers' convention. It Is in-
tended that the paper weight will act as
a reminder when the company's agents
arc calling on the trade, and is not for
general distribution.

The book department of the Engineer-
ing News Publishing Company has been
purchased by the McGraw-Hill Book
Company. 239 West Thirty-ninth street.
New York. This adds to the list of the
McGraw-Hill Book Company a consider-
able number of Important standard
treatises, primarily in the field of civil
engineering. The transfer of this busi-
ness was made on November 6.

S3<>

POWER

November 28. 191 l

On Auf,aist i, James Sclicr-
inerhom, publisher of the Delroil
Times, stepi)e(l fcjrward upon the-
])latform at Kord Hall, Boston,
and delivered a memorable ad-
dress.

He spoke for the doctrine of
truth in advertising.

Tlie occasion was the seventh
annual convention of the Associated Advertising Clu!)s
of America.

Three thousand advertising men cheered his effort
and echoed his sentiment.

To that part of the jjublic which has always read ad-
vertisements with the tongue in the cheek, that speech
and that convention would have been a revelation.
For advertising's representative men put themselves
squarely on record as believers in these fundamental
facts — in all the world there is no more potent argu-
ment for a good article than the truth about it, and
it doesn't pay to advertise a poor article.

That's a combination of ethics and business that
protects the buyer anywaj' it is read.

In part, Mr. Schermerhorn said :

"I believe this is the place and time to come with
a plea for an ethical test of advertising. Splendidlv
your president has sought for the past two years to
give the advertising craft the dignity and tone of a
profession. If you are to become a profession, you
must here and now formulate a code. That code need
Ixit spell one word, truth, and all other wortln- things
shall be added imto \(ni.

"It is a fitting place to thus exalt your calling.
Tmth took entire charge of Boston's earliest adver-
tising. There was no benzoate of bimcombe in the
copy from Concord and Lexington, from Bunker Hill
and the Boston Tea Party.

''The advertising author ought to aspire to truth,
not only for truth's sake, but because .something of
the soul of the artist and poet should be in his work.
The advertiser is really the literary exponent of an age
of commercial romance, when the fair\' fables of Gal-
land and (Vimm are being outdone in the astonishing
achievements of the business world.

"So the advertiser must be true to his task — as
true as the historians, dramatists and poets who have
cinhalmed the very mood and temper of their times
in imperishable literature.

"Chma is wiping out the
opium habit by stopping the cul-
tivation of the poppy. You can
correct dishonest advertising bv
cutting oflf the copy.

" Could anything be more sim-
ple? Truth stands at the door
and knocks. Truth has tried
other doors. Opportimity may

knock but once, but Truth can show you a severe case

of abrasion of the knuckles.

"She has bade the subscriber let her in; but the
reader is generally unresponsive. He possesses all
the widely heralded instrumentalities for getting what
he wants — initiative, referendum and recall — but he
tries none of these progressive weapons upon the
newspaper that betrays his confidence and profanes
his home.

"Truth has pounded upon the prosperous pub-
lisher's door, but the impatient rap has been drowned
in the roar of the octuples.

"vSome publishers whose presses do not run so
long and so hard have heard the knock.

" UTiy not give the place of your present delibera-
tions a new renown through the deliverance of adver-
tising from dishonor, and impart to Faneuil Hall,
consecrated shelter of free speech and tmfettered
trade, the later glory of being the cradle of an emanci-
pated press?"

The day is not far distant when advertising
will shake ofl finally and for all time the burden of

Imnk it has had to bear.

It will be the work of a trinity — the honest adver-
tiser, the courageous publisher and a discerning public.

There is but a modicum of fake machinerj'
advertising. Aside from all things else, the initial
investment is too great to warrant building poor
machinery in the hope that its sale can be forced
through skv-rocket advertising and selling methods.

In the next place no reputable pubUsher will
jiermit the advertising section to be encumbered with
fake ads if he knows it.

Thus the Selling Section, containing the an-
nouncements of reputable manufacturers who court
the fullest |)ublicity, is a safe and sure guide for everj-
buyer of ])ower-plant niachinerv' and supplies.

Vol. 34

NKW ^ORK, DECEMBER 5, 1911

No. 23

IX a factor)', demands for power outgrew the ca-
pacity'' of the engine and boiler, and the capacity
was to be doubled immediately, with provisions
for future increase in capacity without changes in
the building.

The engineer who had operated the plant was
consulted as to the advantages of several different
types of installation: the reciprocating engine, simple
or compound, with or without condenser; oil and
gas engines, belted or with electric transmission,
and the turbine with group or individual motor drive.
But as the business had outgrown the capacity of
the motive power, so had the requirements of the mo-
tive power outgrown the capacity of the engineer,
and he was worthless as an adviser.

He had been in the place most of his working
years. It was here that he learned to handle the
engine, boilers and pumps. He learned to do this
well, but he never learned more. The boilers were
clean and well cared for ; the pimips were kept mechan-
ically in good working order; the engine was attended
to with all of the faithfulness of a plodder who cfmld
almost use an indicator. As an engine tender he had
been a s-uccess, but he had never lifted his eyes to the
possibilities of his calling.

The old engine ran noncondcnsing, so he never
thought of how much a knowledge of the principles of
condenser operations might benefit him.

Shafting and belting transmitted the power to
the various machines and he never considered the
advantages of the electric drive.

Of the turbine he had heard conflicting stories,
but had never seen one. He was a "practical"
engineer who had no time for frills, theories and
technical papers. He had nm his engine and boiler
for years without a shutdown for any accident to the
machinery under his care. He had been a faithful,
crmscientious. patient worker, with not a thought
l>evond the dailv routine rif his duties.

But the plant, already past his control, was to
be enlarged and along lines in which he was ignorant.
Finding him lacking m those things needed for the
handling of the new and radically difTe'rent plant,
the consulting engineer imder whose .supers'ision the
new apparatus was being installed, asked the manager
one day what arrangements were being made to get a
man to take charge of the new machinery.

He was told that as yet nothing had been done,
as it was expected that the old engineer would
be able to handle it.

"I know," said the engineer, "that you appreciate
the service of the old man. for he has been faithful to
the extent of his ability. He has served the engine,
but he has not served you in that he has not kept
up with the times. He grew to the job when the
responsibilities were light. But while the plant grew
he stood still. He has kept the engine from going
to wreck. He has confidence in the old engine, but
none in himself. He can run an engine, but he cannot
run a power plant.

" Charge must be given to a man who has lived up
to his opportunities for keeping in touch with progress in
the generation and transmission of ]X)wcr. This your
man has not done, and one who has must be selected.
I am not misjudging the old man's mistaken fidelity,
and a position among the a.ssistants might lie found
where patient, faithful plodding will suffice. But
for your motive pf)wer you must have a man who
knows and one who knows that he knows."

The manager thought a moment, and then said:
"I think you arc right. W't- will have in Idok for the
right man."

The engineer was right, and this manager is only
one of many who arc looking for the right men — not
men to run engines and boilers but men to run steam
power plants.

838

P O W F. R

December 5, 191 1

Where Current Is Sold for 2\ Cents

The city of San Francisco is blessed,
or otherwise, whichever way one looks
at the matter, by having several sepa-
rate public light and power companies,
supposedly in active competition. The
plant of one of these companies, the
Municipal Light and Power Company, is
interesting from a mechanical point of
view in several particulars. Perhaps it
is all the more interesting by reason of
the fact that the company sells current
at a flat rate of 2' cents per kilowatt-
hour.

The plant is located on Stevenson
street, almost directly in back of the
Claus Spreckels building, which is on
the corner of Market and Third streets,
in the heart of the business district of
the city. From the consumer's point of
view there is but one unfortunate fea-
ture about this plant — it is too small.
Its total rated capacity is only 2240
kilowatts and its service lines extend for
only a few blocks.

From a mechanical standpoint the
plant is interesting because of the large
amount of apparatus contained within
the given area. Fig. 1, showing a gen-
eral view of the generator section of the
plant, serves to illustrate the congested
conditions. Fig. 2 is a plan view show-
ing the location of the main pieces of
apparatus.

The plant contains three Westing-
house-Parsons turbo-generators; two
are of 650 kilowatts and one is of 940
kilowatts rated capacity. All three units
run at 3ti00 revolutions per minute and
generate current at 2300 volts. The cur-
rent is transmitted at this voltage and
stepped down at destination to 240 and
120 volts.

The two small machines have one
Worthington surface condenser each,
containing 2818 square feet of con-
densing surface. The wet-vacuum
pumps, one for each unit, are of the
Blake "Featherweight" simplex type,
7'j by 14 by 10 inches in size; there are
no dry-vacuum pumps.

The condenser for the large inachine
is a Wheeler, containing 4107 square
feet of condensing surface and equipped
with a 10 by 20 by 16-inch Blake,
"Featherweight" simplex wet-vacuum
pump and a 10 by 20-inch "Rotrex" dry-
vacuum pump, chain driven by a 6!I>-
horsepower motor.

Cooling Tower

As the Municipal Company's plant is
located too far from the waterfront for
sea water to be available for condens-
ing purposes, fresh water is used,
recoo'led in a cooling tower. A
forced-draft type of tower was erected
for these reasons: the forced-draft type

.4 central station not-
able for economy in space
IK (II pied /m" //'(' apparatus.
I'kuit contains Parsons
turbines, centrifugal circii-
latiug pumps, motor gcii-
irator.^. ilccator pumps,
etc.

I'hc cooling toiccr, built
according to design re-
cently suggested by J. R.
Bibbiiis, lias proved to be
efficient.

A n ingenious oil storage-
tank indicator is described.

loses no water through windage, which
is a point in its favor where water is
costly; the forced-draft tower is less
bulky than the natural-draft or atmos-
pheric types, hence it is cheaper to build
and requires less foundation area. A

built. With the old tower it was dif-
ficult to get a vacuum better than 23 or
24 inches; with the new one 28'/ j in-
ches are frequently obtained. The old
tower was filled with sets of horizontal
wooden gratings and the air blast was
supplied by the large disk fan shown in
Fig. 3. The chimney for this tower is
the large circular steel stack shown at
the left in Fig. 4. Two faults were dis-
covered after the tower was put into
operation. The arrangement of the grat-
ings did not divide the water into fine
enough particles to produce good cool-
ing effect. And the fan was not of the
proper type to operate successfully
against the friction head of the tower
and furnish the required volume of air.
The second tower is the rectangular
corrugated sheet-iron structure seen in
Fig. 4. This tower is filled with tiers of
very nearly vertical wood-lath mats in
the manner and of the design suggested
by J. R. Bibbins in a paper presented to
the American Society of Mechanical En-
gineers about two years ago, an ab-
stract of which was printed in Poii er
for January 18, 1910.

Fic. 1. Pakt of the Equip.ment of the .MUNICIP.^L Pl.a.nt

point which is sometimes against it is
the fact that it requires power to run the
blast fan. In the present instance this
point counts for practically nothing, be-
cause the fan is steam-engine driven and
the exhaust from the engine is sold for
heating purposes.

The tower originally installed did not
prove to be adequate and a new tower,
of different design, has recently been

The fan which furnishes the air blast
for the new tower is of the Sirocco t>T5e
and was furnished by the American
Blower Company. It has an 8 by S-foot
runner, double inlet, and a 64 by 128-
inch outlet. Under normal operation the
fan makes 55 revolutions per minute and
delivers about 92,000 cubic feet of air
per minute against a head of J4 inch,
water gage.

December 5. 1911

P O W E R

839

ClRCUl ATlNG-iSATER PUMPS

There are three circulating water
pumps of the centrifugal type, 10 inches
in size. Two of these are direct driven
by 50-horsepower induction motors and
the third is driven by a 75-horsepower

OiL-sTORACE Tank Indicator
An ingenious arrangement for ascer-
taining the quantity of oil in the storage
tanks has been devised by the chief en-
gineer. It is illustrated diagrammati-
cally in Fig. 5. A homemade glass U-

Fic. 2. Plan Showing Location of Main Apparatus

motor, all run at a speed of 850 revo-
lutions per minute. The piping is so
arranged and bypassed that any com-
bination of pumps may be used.

Boilers

The boiler equipment consists of
four specially constructed Stirling
boilers, specially constructed to accom-
modate the small amount of head room
available. One is of 350 horsepower
rated capacity and the other three are
of 450. Two of the larger boilers have
superheaters which effect a superheat of
.50 degrees. Steam is generated at 170
pounds pressure, gage.

As in almost every steam plant in
California, the fuel is crude oil. This is
stored in three tanks of 1 10 gallons capa-
city each, buried 2 feet below the grate
level as prescribed by city ordinance.

The oil is pumped to the burners by
a 6\lxH-inch duplex pump, through a
tubular heater in which it is heated to a
temperature of about 150 degrees. The
oil-pumping equipment is in duplicate.

The oil pressure is regulated by a Witt
pump governor which is set for a pres-
sure of .5f) pounds per square inch. The
steam used by the burners is super-
healed by being passed through a loop
of steam pipe which is hung on the in-
side face of the front wall of the boiler
furnace. The supply of steam to the
burners is regulated by hand. Hammcl
back-shot burners are used in Hammel
furnaces. The small boiler has three
burners and the large boilers have four
each.

tube of suitable size is mounted on the
board A. A 'g-inch wrought-iron pipe
is connected to one leg of the tube and
run to the bottom of the storage tank as
shown. Anywhere between the U-tube

the lower end and air beings to escape
up through the oil. Of course, there
must be nothing but atmospheric pres-
sure in the oil tank. The air pressure
in B also displaces the mercury in the
U-tube, the amount depending on the
depth of the oil in the storage tank,
the displaced mercury being balanced,
so to speak, by the displaced oil. Thus
the scale on the board behind the U-
tube may be graduated in barrels of oil
and the amount on hand may be ascer-
tained at a glance. The accuracy of
this arangement depends on the pipe B
and its connections being air tight.

This same principle may be applied
equally well to water-storage tanks, etc.

The three motor-generator sets shown
in Figs. 1 and 2 are used for electric-ele-
vator service exclusively. They gener-
ate direct current at 250 volts. Two are
of 150 kilowatts capacity and one is of
300.

Elevator Pumps
The plant contains two hydraulic-ele-
vator pumps. The larger one is a re-
built compound duplex pump, the water
end of which once belonged to a Crane
crank-and-flywheel type. The steam end
of the original machine was removed and
a new steam end, furnished by the
George Dow Pump Company, was put
on. The sizes of the original steam cyl-
inders were 16 and 20 inches in diame-
ter and 16 inches long. The new steam
cylinders are 12 and 20 inches in diame-

and the tank a pipe connection is made
with the compre«sed-air svstem.

By opening the valve of the com-
prciscdair pipe a very slight amount, the
air pressure in pipe B gradually builds
up until all of the oil is forced out at

ter with an IS-inch stroke; the water cyl-
inders are « inches in diameter. The
clearance which existed with the old ma-
chine made it possible to increase the
stroke from Ifi to 18 Inches with very
little alteration lo the water cylinders.

840

POWER

December 5, 1911

This pump handles about 53,000 cubic
feet of water per day of eight hours
against a pressure of about 275 pounds.

The other pump is a MCorthington com-
pound duplex, 16 and 22 by S'A by 12
inches in size. It is used on Sundays

and holidays and in emergency. These
pumps operate the elevators in the
Spreckels building, across the street.

Exhaust-steam Heating
Although the heating requirements of
the climate of San Francisco are not
severe, the season is a rather long one.
Hence, exhaust-steam heating is profit-
able. All of the exhaust from the steam
auxiliaries is sold during a large part of
the year to heat nearby office buildings.

Fic. 4. Old and New Coolinc-to\xek Stacks

Fig. 5. Oil-storage Tank Indicator

Test of World's Largest Boilers

The November Journal of the Ameri-
can Society of Mechanical Engineers con-
tains a paper by D. S. Jacobus upon the
tests of the large Stirling boilers at the
Delray station of the Detroit Edison
Company. These boilers are the largest
in the world and it is planned to eventual-
ly install ten at this station. The first
of these has now been in service for 18
months, the second and third for nine
months and two more are being erected.

Results of a series of
tests on the Stirling boilers
at the Delray station of the
Detroit Edison Company,
7i'hich carry individual loads
equivalent to 8ooo kilowatts.

A detailed description of these boil-
ers was given in the October 11, 1910,
issue of Power, but at that time data
were not available as to the actual per-
formance. The tests described by Mr.
Jacobus extended over a period of three
months and were made under his direct
supervision by a staff of experts from the
engineering department of the Babcock
& Wilcox company.

Two series of tests were made, one

T.\BLE 1. TEST WITH RONEY STOKERS

o
S

3

c

1

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h

a

3
|l

Average Dkaft,
Inches of Water

Temperature. Degrees
Fahrenheit

1.

p-

u

1=

bo

a

i

B
is

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1

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3

1
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^ 3

1

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1
II

1 ■

2
3
4

0
16
17
18

2-4*
5-6*

2.5

24

24

30

24

24

32

16 o

24

90

190
1S8
192
192
187
191
188
194
194
191
189

0.42
0.0.-.
0.51
0 . 5,i
0.16
0.57
0.17
0.95
1.11
0.38
0.38
1

0.32
0.16
0.39
0.22
0.24
0.26
0.23
0.34
0 . 33
0.28
0.25

0,10
0.06
0,21
0.02

n 10

0 16
0 12
0 , OB
0,05
0 , 06
0.05

135.3
115.2
130.5
136.4
107.5
136.8
102.1
132.6
157.6
130.9
125.7

184
180
184

181
1S3
185
177
179
178
182
183

576
480
542
670
483
662
460
636
694
572
575

903
851
992

1064
847

1085
678
927

1029

602
479
565
709
501
668
467
622
709

16.73
12.58
18.23
25.97
14.81
25.32
14.92
30 . 85
33 . 60
19.81
21.21

0 15
0.18
0.16
0.15
0.19
0.11
0.18
0.15
0.13
0.15
0,14

0.47
1.43
1.56
1.34
1.16
1.24
1.19

11.52
11.71
11.42
10.74
11.62
10.89
12.08
11.46
10.66
11.06
10.98

3 63
2.78
3.92
5.26
3.24
5.20
3.40
6.67
6.75
4.13
4.39

2491
1903
2691
3606

3565
2333
4572
4630
2833
3012

105 . 0

so.o

113. S
1.52.4

94.0
150,7

98.6
193.3
195.7
119.8
127.3

77.84
79.88
77.45
75.78
81.15
75.28
80.98
76.73
75.57
76.13
76.23

'Includes periods between tests.

December 5, 191 1

POWER

841

Section through Boiler, Showing Both Taylor and Ronev Stokers

on a boiler fitted with Roney stokers,
and the other on a boiler fitted with
Taylor stokers. The boilers are double
ended and to avoid unnecessary duplica-
tion in the accompanying illustration, one
end is shown with Roney stokers and the
other with Taylor stokers; but it should
be remembered that both ends are alike
in the actual installation.

In the boiler fitted with Roney stokers,
four are used — two at the front and two
at the rear with a low division wall be-
tween the stokers and a bridgewall be-
tween the two sets. The Taylor stokers
have 13 retorts on each end, or 26 in
all. The retorts on each end are set
in a continuous row so as to provide
an unbroken fire surface from one side
of the boiler to the other. With these
stokers there is no bridgewall, and when
the dumping plates are covered with coal
there is a continuous fuel bed beneath
the entire boiler.

Giving a general resume of the prin-
cipal features of the boilers as con-
tained in out; previous description, each
boiler is 30 feet 6 inches wide, 26 feet
6 inches deep and stands 33 feet 9 inches
from the floor to the center line of the
drums. It contains 23,654 square feet
of effective heating surface and is pro-
vided with superheaters for supplying
steam at 150 degrees superheat. The
grate surface per boiler for the Roney
stokers is 446 square feet and for the
Taylor stokers, 405 square feet, thus
giving as ratios of grate surface to heat-
ing surface, 1 :53 and 1 :58' '> respectively.

Table 1 shows the results of the tests
with Roney stokers and Table 2 with
Taylor stokers. It will be seen from
these tables that the combined efficiency
of the boiler and furnace varied from
about 80 per cent, at slightly below rat-
ing to about 76 per cent, at double the
rating. In calculating these efficiencies
the steam used for driving the stokers
and for producing the forced blast for

T.VHI.l

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;.-<II.TS WITH

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7.-.0

160

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1 1 311

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12

188

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626

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7 41

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7.1.66

3. 04

842

POWER

December 5, 191 1

the Taylor stokers was not deducted from
the total steam generated by the boiler.
The steam used by the Roney stokers
was about I 'A per cent, of the total steam
generated by the boiler and for the Tay-
lor stokers from 2;< to 3 per cent. The
effect that this steam would have on the
plant economy depends upon the ability
to use the exhaust for heating the feed
water. In the case of the Taylor stokers
all of the exhaust steam from the tur-
bines driving the forced-blast fans may
be carried to the feed-water heater,
whereas with the Roney stokers only
about U of 1 per cent, of the 1 'j per
cent, used may be so returned as the
greater part of the steam is used in jets
which supply steam below the ignition
arches of the stokers, and therefore
passes away with the chimney products.
In a plant in which the auxiliaries are
electrically driven, any power required
to operate the forced-blast apparatus
wou'.d be a direct loss and, assuming in
the case of the Taylor stoker that the
steam consumption corresppnding to the
power required to drive the electrical-
driven auxiliaries is one-half that found
in the tests, the steam required to operate
each of the stokers would be about the
same.

The results of the heat balances show
that the average radiation and unac-
counted-for losses were only about 2]/2
to 3 per cent.

Although the tests show a maximum
of about 5000 boiler horsepower, it is
stated in Mr. Jacobus' paper that each
of these boilers is required in all-day
service to carry a load of 6000 kilowatts
and in the evening from 7000 to 8000
kilowatts.

Effect of Air Pressure
By Charles R. Moore

It is a matter of experience that air
exerts a pressure of 14.7 pounds per
square inch at sea level and that this
pressure diminishes as the hight above
sea level increases. This pressure may
be easily measured by noting the hight
of a column of mercury in a glass tube
sealed at the top and open at the bot-
tom, which has been previously filled
with the liquid and inverted in a vessel
containing a small amount of the mer-
cury. This instrument is commonly
known as the barometer. Of course, the
hight to be measured is the distance be-
tween the mercury levels. A knowledge
of the density or specific gravity of mer-
cury enables one to convert this dimen-
sion into pounds per square inch. A
fact not commonly noticed in connection
with this instrument is that a collapsing
force is exerted on the tube, which varies
in intensity directly as the hight of the
mercury. This means that each area on
the tube at the top of the column, equal
to the cross-sectional area of the. col-
umn, has a force inward exerted upon it

equal to the entire weight of the sus-
pended mercury.

Water may be used instead of mer-
cury, but a tube very much longer must
be had. As is well known, the mercury
column will be normally about 30 inches,
while a water column would be about 34
feet in length. If a tube shorter than
34 feet be used, it will stand full, and
the inward pressure at the top will be
the same fractional part of 14.7 pounds
per square inch that the length of tube
is of 34 feet. Thus the pressure exerted
by a water column 10 feet long would
be approximately

- X 14.7 = 4.32 pounds per square inch
34

In case a tube longer than 30 inches

for mercury and longer than 34 feet for

water is used, the liquids fall to the

levels before mentioned and a vacuum

aversion to air pressure, and cared but
little why the water came up into the
feed pump, so long as he knew the de-
tails of how to make it come and how
to keep the boilers full.

The writer visited his plant one Sun-
day afternoon just as he had finished
cleaning one of the boilers. This of
the tubular type, and had been set
rather high in the brickwork, from
one side of which the blowoff pipe was
led to a drain tile some feet below the
floor level. The mud valve was placed
just below the ell and further down a
stop valve was located.

As usual in this type of boiler, there
were two manholes, one at each end in
the flue sheets. The rear one was near
the top and the front one close to the
bottom of the shell. To get at the front
head the breeching door had to be raised

^r^^ PowEi(

The Suction Drew His Arm into the Manhole

exists in the upper part of the tube. The
maximum inward collapsible pressure,
therefore, which can be produced by this
means is 14.7 pounds per square inch.
Engineers as a rule have a keen ap-
preciation of this fact, but occasionally
one is found who, if he really knows
why a pump can lift water, is more or
less careless in his reckoning with this
particular circumstance. Such persons
usually come to grief sooner or later, as
the following incident will show:

John had charge of the power end of
a small factory and was proud of the
fact that he had been more or less suc-
cessful in keepins up his part of the
work without paying very much attention
to theory. He had received his training
in the school of hard knocks and had
studied his engines and boilers carefully
in regard to their practical operation.
"How to do things" interested him im-
mensely. Adjustments, filing, a'ining,
etc., were his particular delight, but
when anyone began to talk angles, veloc-
ity of gases in stacks, combustion, inches
of draft, etc., he evmced but little in-
terest. John seemed to have a special

and John had fixed up a pile of small
boxes in front of the fire doors on which
to stand.

When I accosted him, he was mounted
on this improvised pedestal examining
the manhole plate seriously. "Anything
wrong?" I asked. "No," said John, "but
the boss will not give me anything but
hemp from which to make gaskets and I
am likely to have a leaky joint here.
Sometimes I get a good fit. but just as
often the job has to be done the second
time."

"Ever try plumbago and oil on your
hemp?" I asked.

"Yes. I have used oil on this one, and
cylinder oil at that, but it is leaking like
a sieve. I just now shut the boiler up
tight with the water at about one gage,
thinking that when the feed pump stopped
the joint would be driven up so tight
it could not leak, but it has made mat-
ters worse."

Sure enough, the leak was too serious
to pass unnoticed, and we both decided
that a new gasket must be made. John
accordingly opened the blowoff valves, and
the kicking of the feed pump reminded

December 5, 1911

P O W E R

843

him that it had not yet been shut off, even
though it had stopped.

"Better open up the gage cocks to let
in a little air. Maybe the boiler will
drain faster," said I.

"Now do not give me another air-
pressure lecture," said John in a frame
of mind none too pleasant. "I guess the
water can get out of that 2' _^ -inch pipe
all right. If it does not, it will come out
when 1 knock the head in." And away
he went to prepare another gasket.

1 plaited four good-sized strands of
hemp fiber for him, and in a short time
we stepped outside to see if the boiler
had drained. No water was flowing ex-
cept a slight trickling and John remarked,
"That water got out mighty quick."

"May be, it is not all out," said I.
John looked at me astonished.

"Why, the valves are wide open," said
he, and with that he hurried to the boiler
room and mounted his pile of boxes. A
monkey wrench was lying inside the
breeching, and, grasping the manhole
plate by means of the small eye arch
cast for that purpose, John began tap-
ping the rim flange with the wrench. He
struck perhaps three blows when sud-
denly he was pulled head and shoulders
against the flue ends. His feet swung
clear of the boxes and his arm was full
length inside the boiler.

He let go of the plate, missed the
boxes and fell in a heap directly in front
of the boiler, only to receive a deluge
of water. He fully realized that the
joke was on him, and after things were
righted, his clothes changed and a good
fire going under the boiler, he turned to

me with the inquiry: "Say, would you
mind helping me figure out exactly what
gave me that baptism?"

After explaining to him such things
as have been stated at the beginning of
this story, we estimated that the dis-
tance from- the manhole center to the
blowoff valve was 4 feet. Using this as
the hight of the water column we figured
as follows: The manhole plate was prac-
tically a 9x 14-inch ellipse, the area of
which was approximately 99 square
inches. The difference in pressure be-
tween the outside and the inside of the
manhole was therefore

99 X 1.74 = 172 pounds
at the time he broke the joint. It was
this which drew the cover in and jammed
him against the flue sheet.

Marine Turbine- Ensrine Installation

G. W. Dickie, in a paper read before
the Society of Naval Architects and
Marine Engineers, at New York, on No-
vember 16, outlined an interesting ar-
rangement of combined reciprocating and
turbine engines for marine work. Al-
though at variance with the practice of
some prominent engineers in this line,
the arguments supporting this arrange-
ment appear logical.

Speaking of the limitations of both
types, Mr. Dickie points out that the tur-
bine begins its work in the wasteful end
and finishes in the economical end,
whereas in the reciprocating engine this
is reversed. In the case of the latter
the chief loss is due to the alternate
heating and cooling of the cylinders
caused by the drop in temperature as the
steam expands, the difference in tem-
perature being much greater in the low-
pressure than in the high-pressure end,
and the consequent condensation due to
the heat abstracted from the steam to
replace that lost in the low-pressure cyl-
inder during the exhaust stroke.

The tu'*-: .. ^. ■ this loss because
the stean. is coi.- iv moving in one

direction on its wa, to the condenser
and the rotor maintains a temperature
which corresponds with that of the steam
at any point in its passage. Mechanical-
ly, however, the turbine is defective, as
a certain amount of clearance must be
allowed between the tips of the rotor
bl9'';r and the casing and also between
ft tips of the guide blades and the rotor.
As these blades, at the high-pressure
end, are very short and the clearance
has to be as great there as elsewhere.
the free passage for steam at this end
is considerable, especially in the marine
type where the rotors are of greater
diameter and the area of the clearance
correspondingly greater. Where the
blade fs only about one inah in length

A tentative arrangement
/or marine practice liith
one reciprocating engine on
the center shaft exhausting
at about 30 pounds abso-
lute into turbines driving
the outboard shafts.

and with. say. 0.05 inch or 0.0(> inch
clearance, there is over 10 per cent, of
clear space for the steam to pass with-
out doing work. At the low-pressure end,
however, where the blades may be 10
inches long, the same clearance would
be only 1 per cent.

The arrangement which has found
favor with those responsible for the most
important installations of power on board
ship, where the two types of engine have
been combined, has been that in which
the steam has been expanded in the
reciprocating engine down to a pressure
of 9 re 10 pounds absolute. This would
give a drop in temperature in the low-
pressure cylinder of about 62 degrees —
■■ay a mean of .31 degrees below the tem-
perature of the entering steam. This is
far below the line where the economy
of the turbine is superior to that of the
reciprocating engine and is undoubtedly
the result of accepting as best the ar-
rangement of two sets of reciprocating
engines and one exhaust turbine be-
tween, the new White Star liners being
notable examples of this arrangement.
For vcr>' laree installations there are
several important advantages afforded by
this arrangement; the size of the re-
ciprocating engines is thus kept within
reasonable limits; the manrruvering power
is fifl per cent, of the total; a breakdown
of the turbine engine leaves the whole

manoEUvering power intact, while a break-
down in one of the reciprocating engines
still leaves 75 per cent, of the propelling
power intact and 40 per cent, of the ma-
nreuvering power available. There would
also be what advantage can be claimed
for twin screws for manceuvering.

Notwithstanding these imponant ad-
vantages claimed for the arrangement of
two reciprocating engines and one tur-
bine, Mr. Dickie believes that better re-
sults, with installations up to 20,000
horsepower, can be secured by having
one reciprocating engine on the center
line delivering steam to a turbine on
each side at about 30 pounds absolute.
This would admit of the center-line en-
gine developing about 40 per cent, of the
total power and, when exhausting straight
to the condenser, at least 60 per cent, of
the full power. The larger and most
effective propeller would be on the cen-
ter line, where its efficiency would have
the best propelling effect. The smaller
side propellers would not require as wide
projections from the side of the ship
and would thus cause less disturbance
to the water in the after run. With the
large propeller in the center, the side
propellers could be run at a greater num-
ber of revolutions than would be advis-
able for the center propeller were it tur-
bine driven. This would permit of the
turbine rotors and casings being of a
moderate diameter. In a 20,(H)0-hor?c-
power set of engines, with the center-line
shaft making, say, 7S revolutions, the side
shafts could be run at about 400 revolu-
tions which would give a diameter of
about S feet to the rotor. This would
enable the turbines to be placed along-
side the reciprocating engine in any mer-
chant ship having that amount of power.

With the reciprocating engine closing
its work with a terminal pressure of 30
pounds absolute, a simple compound en-

844

POWER

December 5, 1911

gine would give satisfactory results.
Wliere tlie total power was to be above
8000 horsepower, it would seem advis-
able to make the reciprocating engine
with two high- and two low-pressure
cylinders, the high-pressure cranks being
180 degrees apart and the low-pressure
cranks 180 degrees apart, each pair being
90 degrees apart; this would produce a
well balanced engine. By a proper ar-
rangement of exhaust from the low-
pressure cylinders, only one change valve
would be necessary. This would be op-
erated by a direct steam cylinder, con-
trolled by a hydraulic cylinder and piston

In nearly all cases there would be room
to install the main condensers on the
outboard side of the turbines, so placed
as to have the exhaust passage in the
middle of the condenser. The channel
ways or connections to the wet-air pumps
would pass through the lower part of the
turbine casings and connect direct to the
lower chambers of the pumps. As the
turbines would not be as long fore and
aft as the reciprocating engine, there
would be plenty of room for all engine-
room auxiliaries.

An objection which might be raised
to the arrangement advocated, is that a

tional losses causing a great curtailment
in the theoretical gain due to the expan-
sion; on the other hand, by delivering
the steam to the turbines at a pressure
and temperature that insure a more
economical continuation of efficiency in
the power developed, the best perform-
ance is obtained with each type of en-
gine.

According to .Alfred C. Lane, formerly
State geologist of Michigan, there are
seven horizons at which the coal occurs
in workable thickness, although it was
formerly supposed that there was only

y t t L t ^-T-^

cn^ji

Arra.ngement of High-pressure Engine and Low-pressure Turbines

so that the movement might be as slow
as required. No steam jackets would be
needed on the cylinders. The exhaust
pipes, however, from the low-pressure
cylinders to the turbines, might be jack-
eted to advantage.

In such an arrangement there need be
no objection to operating the air pumps,
of which there would be two, through
levers worked from the crossheads of the
low-pressure cylinders. These would be
placed so that the foot valves would be
as low as possible, the channel way be-
ing in line with the lower face of the
bedplate so as to be below the lowest
part of the turbine casings, it being im-
portant to have them thoroughly drained.
The dry-air pumps should be operated
in the same manner as the wet-air pumps,
being placed above the operating levers
in a direct line with the wet pumps. The
feed pumps would be operated inde-
pendently and thus remove another
source of trouble from the main engine.

breakdown of the reciprocating engine
would deprive the ship of backing power.
This objection is admitted, yet from the
simple construction of the proposed re-
ciprocating engine a breakdown involving
the stopping of the engines for good
seems rather a remote possibility and, if
it should happen, the turbines could keep
the vessel going ah;ad.

If right in the claim that the turbine
can show a higher efficiency than the
reciprocating engine to a point much
higher in the expansion curve than 9
or 10 pounds absolute, then the arrange-
ment Mr. Dickie proposes would give
a better combined economical result and
be simpler and less expensive.

In utilizing the expansion in reciprocat-
ing engines down to a pressure of, say.
9 pounds absolute, cylinders of large
dimensions must be provided subject to
marked changes in temperature at every
revolution, involving large losses due to
condensation combined with large fric-

one workable bed in the State. The
coalfields of Michigan are confined en-
tirely to the lower peninsula, with an area
of approximately 11,000 square miles.
This is the only known coalfield within
the drainage area of the Great Lakes.
Michigan's original supply of coal, ac-
cording to the estimate of M. R. Camp- •
bell, of the United States Geological Sur-
vey, was 12.000,000.000 tons, contained
in an area of 11.000 square miles of
coal-productive territory.

Iowa probably ranks second among the
States west of Mississippi river in order
of priority as a coal producer. Its pro-
duction to the close of 1910 amounting
to nearly 164.500.000 shon tons. The
original supply of coal in Iowa, as esti-
mated by .M. R. Campbell, of the United
States Geological Survey, was 29.160,-
000.000 short tons, from which it appears
that at the close of 1910 over 28.900.000,-
000 short tons.

December 5. 1911

POWER

845

Strain Measurements of Boilers

It is rarely that one gets a 72-incti
boiler to test to destruction. Two such
boilers which had been in active opera-
tion for 21 years were contributed for in-
vestigative purposes by the late Nicholas
Sheldon, treasurer of the Kendall Manu-
facturing Company, of Providence. R. I.
They were made by the Whittier Machine
Company, of Boston, Mass., out of "Ben-
zon" steel, were put into service in
March, ISS-l. and had never required re-
pair or renewal in any part. They were
made in five courses, two sheets to a
course, and had the following general
dimensions:

-?•>

in

LeDglli. over dry sheeX

IC

ft

Thickness of shell

%

in

Thickness of heads

Vj

in

Numl>er of tubes

140

liiameter of tubes

.... :{

in

!.">

ft

1 Hameter of demo

J ft. r,

in

Longitudinal spiims. double-iiveled lap jnints,

^i-inch riveis. L'-inch pitih. punched linlns.

rows -K inches apart, rivets staggered.
tJIrth seam. ■'Vi-lnch rivets, 2ii-incli pitch.
Heads sta.ved. each, with 14 braces.
Cast-iron manhole frames and safety-valve

nozzle.
Supported by lugs, three on a side.
The feed water came from the I'awtuckil

river.

The utmost advantage of this oppor-
tunity was secured by placing in charge
of the tests James E. Howard, qualified
by long years of service as the head of
the Government testing plant, at the
Watertown arsenal and now engineer-
physicist of the Bureau of Standards, at
Washington. He was advised and as-
sisted by Francis B. Allen, vice-president
of the Hartford Steam Boiler Inspection
and Insurance Company. The tests were
made at the W. H. Hicks Boiler Works,
Providence, and form the subject of a
paper to be presented at the December
meeting of the American Society of Me-
chanical Engineers, from which the fol-
lowing information is derived:

The tests were made by subjecting the
boilers to hydrostatic pressure and
measuring the deformation at various
points. For this purpose holes about
0.05 inch in diameter and 0.10 inch deep
were drilled 10 inches apart in various
portions of the shell, and reamed with a
reamer having an angle of 65 degrees.
A 10-inch strain gage having conical
points with an angle of 55 degrees, ad-
justable with a micrometer screw, was
used to measure the distances between
these holes as they varied under stress.
The difference in angles made the gage
bear near the surface of the sheet and
it is believed that the readings are reli-

would produce an elongation of this
amount in a distance of 10 inches is .VK)
pounds per square inch, assuming a mod-
ulus of elasticity of 30.000,000 pounds;
that is. supposing that the stress per
square inch divided by the stretch per
inch of length would equal 30.000.000.

Txvo "J 2 -inch boilers were
tested to destruction by stib-
jecting them to hydraulic
pressure.

At 266 pounds the dome
of the first boiler leaked so
badly that it had to be re-
moved; at 270 pounds the
cast-iron manhole frame
fractured, and at 295
potnids the bracing of the
head gave out.

The second boiler was re-
duced as nearly as possible
to a simple cylinder before
the test commenced , by the
removal of the dome and
manhole frame, but at 335
pounds the rivets of the
patch with which the man-
hole was covered sheared,
allowing the boiler shell to
rupture.

The boilers tested were of a very
simple type, yet in very few instances
were strains developed corresponding to
those which would be indicated by the
usual calculation for strains in a cylindri-
cal shell subjected to internal pressure.

pressure required to produce it. A pres-
sure of 60 pounds per square inch in the
interior of a cylinder of this diameter
and thickness of shell would, for in-
stance, produce a stretch of nearly
0.0020 inch in a length of 10 inches; and
a pressure of 300 pounds a stretch of
about 0.0095 inch. The points so de-
termined would lie in the heavy straight
line of the diagram marked £ -- 30.000,-
('00. The distortions actually found were
5et off in the same way and connected by
the lighter lines. They show the exten-
sions of the third and fourth sheets of
the boiler, counting from the front on the
right and left sides of the boiler respec-
tively, taken at the middle of the lengths
cf the courses. The courses are lettered
A, B, C, D, E; C— 16 R. on the diagram
means gaged length 16 on sheet C, right-
hand side. These follow the heavy ref-
erence line for the ideal condition quite
closely upon one side of the boiler, but
the leaning to the right of the plotted
lines of the other diagram indicates more
than a normal stretch.

The strains produced at the various
places measured are plotted in this way
and the diagrams accompany the paper.
There were in all 165 gaged lengths and
some 3300 readings. In Fig. 2 the lines
£-12, which are the plots of strains oc-
curring nearly over the rear head, show
the effect of the head in preventing stretch
of the sheet. £ is the rear sheet. £-8 was
taken near the girth seam between this
and the next sheet and £-16 in the center
of the rear sheet close to, but not span-
ning, the longitudinal joint. Diagrams

i

A

^^A

/

^

D

ie(f>J ^

V"

A

Y-

^^'

'Sifi^

/

f

<^;

/

A

<ftj

//

J

'\

v

//•■

^4

^r

<]/ /'

'^>*^

, ^ !

y

'o*

/I

1

/y

•t- — '

A

/

/

1 1 !

J —

OOOF.

0.00«

0.010

0.002

0.004

0.006

Strains

In Inches

Fig. 1. Curves of Tangential Extension, Solid Sheets, at Miohle of
Length of Courses

In Fig. I are laid off in a horizontal
direction the amounts of stretch which
would be produced by various pressures
per square inch in a plain cylinder and
wilh a modulus of elasticity of .Vl.OOO.-
000. each at a hight corresponding to the

ol the boiler arc given in the paper show-
ing the location of each of the spans
measured. Fig. 3 shows the extension
across the longitudinal seam on the mid-
dle course, curve C-7 being taken at the
frnnt ril(T f'-ll at the rear edge and

846

POWER

December 5, 1911

C-15 in the middle of the sheet. The
author points out that in the case of a
three-course boiler with one sheet to a
course, as found in current construction,
it would seem that a double riveted lap
joint might occasion (by reason of the
greater extension) an excessive stress in
the solid sheet abreast the end of the
seam, under certain pressures.

Pressure on the exterior of the tubes
necessarily extends them in length. The
amount of the extension appears to de-
pend upon their position with reference
to their proximity to the shell. Tubes

very top of the boiler the strains were
extensions of a pronounced order.

The tests for which the figures and di-
agrams in the paper are given were made
upon only one of the boilers. In the
tests of the first boiler greater strains
were displayed in the vicinity of the dome
and the manhole frame than at other
parts of the shell, which resulted in an
early failure at these places. Actual
rupture of the dome was not accomp-
lished, but leakage along its single-riveted
longitudinal seam became so great at 263-
pounds that it was necessary to remove

A feature, however, in the test of the
first boiler was absent or obscure in
that of the second. Measurements of
strains across the longitudinal seams in-
creased progressively in passing from the
front to the rear end of the boiler. The
author says: "While these seams were
not directly exposed to the heated gases
over the grates, nevertheless it seems
probable that a wider range of thermal
conditions prevailed in the vicinity of
seams at the front end over those at the
rear end of the boiler. If such was t!ie
case it would aid in explaining the

0.008

0.010

0.012

0.014

0.016

0.018

0.004

0.006

0.008

O.OIO

O.OIE

0.014

S+rain5

n Inches

Fig. 2. Curves of Tangenti.al Extension, Solid Sheets,
End Course Near Rear Head, Girth Seam
AND Middle of Length of Course

Fig. 3. Curves of Tangential Extension, across Longi-
tudinal Sea.ms, at Middle of Length of
Course and at Edges

adjacent to the shell extend less than
those at the middle of the rows, a re-
straining influence from the shell appear-
ing to affect the outer ones.

In a plain cylindrical shell, increase in
diameter would necessarily be attended
by a defiinite amount of endwise con-
traction, eliminating the effect of pres-
sure on the heads. The tests showed
that there were parts of the boiler which
were nearly free from longitudinal
strains, while there were other places in
which the strains were reversed and long-
itudinal extension shown instead of con-
traction. Along the lower quarter of the
boiler the longitudinal strains were con-
tractions, while along the upper quarter
they were in part contractions and in
part extensions. Figs. 4 and 5 show the
amount and character of these strains at
270 pounds in the middle of the sheets
and across the girth seams respectively.

It will be noticed that the lower part
of the shell contracted notwithstanding
the fact that the tubes were extended by
the exterior pressure to which they were
subjected. This behavior calls for bend-
ing at the flanges of the heads to com-
pensate for the difference of these move-
ments. The six through braces would re-
lieve the shell of a portion of the longi-
tudinal tension coming from the heads in
the upper half of the boiler. Longitudi-
nal gaged lengths on the upper part of
the shell showed diminished contractions
over those observed on the lower portion
or displayed strains of extension. On the

the dome and close the opening to it in
the shell with a patch in order to reach
higher pressures with the pump available.
At 270 pounds the cast-iron manhole
frame fractured across the middle of its
length. Another patch was then put on
the shell covering the manhole and the
test resumed, when at 295 pounds the

greater slip of the forward seams."
Leakage at the longitudinal seams began
at 120 pounds and became general at 180,
but at this time the slip of the joints had
become pronounced and necessarily dis-
turbed the calking.

The second boiler was stripped of its
dome and manhole frame and the open-

flc. 4. longitidinai. strains on solid sheets at middle length of courses.
Minus Signs Indicate Longitudinal Contraction; Plus Signs, Longi-
tudinal Extension

rupture of three braces of the front head
occurred. The test was then discontinued
and the boiler dismantled. The strain
measurements made upon the boiler were
of the same order as those reported for
the second and the results were similar.

ings covered with patches before it was
tested. The heads were strengthened by
means of six 1 '4-inch through braces.
The cast-iron safety-valve nozzle was al-
lowed to remain in place, but was event-
ually replaced by a soft patch after 300

December

1911

POWER

847

pounds pressure had been applied and
released, as the distortion of the shell
under the flange of the nozzle caused
leaks impracticable to calk. During the
test the boiler was supported on two
wooden shoes sawed to fit the cur\ature
of the shell.

When the pressure in the boiler was
increased from 300 pounds, the highest
indicated on the diagrams, to 335 pounds
the manhole patch ruptured. Three of
the rivets were sheared by the tangential
stress of the shell followed apparently by
the fracture of other rivets by tension on
their stems which pulled off the heads

veloped at the side of the manhole patch
and at the side of the safety-valve noz-
zle, and suggests that if such abnormal
stresses can occur with so simple a struc-
ture as the boiler under consideration, it
might be well to apply this method of ex-
amination to the strains produced in
boilers of more complex construction.

COo and Boiler Efficiency

By E. a. Uehlinc
I notice that R. S. Wilhelm, in the
article, "Value of CO.- Recorder," in the
October 2-1 issue, seems to consider that

3-

^

Hp

■

-f-.r/oz.'f

■*.ooast
■1- oc/^ \

f

::^M

m

-*' TOOiit/

-OOKf^

-^r. :z%%

7; , -ae^/8

-ooze

-.or>i->.-r

^«,»-

—.nn//

"•1

MRAINS ACROSS GiRTH SeAMS, AlSO StK\...

Gaged Lengths of Courses

and finally tore the sheet longitudinally
along its upper element, starting this
fracture at a rivet hole of the manhole as
shown in Fig. 6.

The shell was repaired by cutting out a
portion of the middle course and putting
in a section the full width of the course
and about 3 feet « ide measured on the

Fio. 6. Manhoi E Patch aftir Ripti re

arc. This was double riveted to the shell
at its longitudinal scams. The hand-
riveted seams extended rapidly, and copi-
ous leaks were started so that at the time
of writing the paper no greater pressure
than that of 33.S pounds, at which the
manhole patch ruptured, had been at-
tained.

In summing up, the author points out
the usual influence of longitudinal scams
in intensifying the stresses in the ad-
jacent sheets, the excessive stress de-

my statement in the August 15 issue, viz:
"Since CO: by itself is not claimed to be
and in the nature of things cannot be a
measure of efficiency." is a contradiction
of. or a» least in conflict with, my previ-
ous statement (June 11 issue), viz: "In
all cases high or low CO: means high or
low efficiency," with which latter state-
ment Mr. Wilhelm agrees. These state-
ments are both true and the one in no
\' ay conflicts with, much less contradicts,
J oth;r.

It will be conceded by all that a re-
rciion in the amount of heat wasted
.cans a corresponding increase in effi-
ciency, and also at any given slack tem-
perature Ih-- greater the weight of gas
per pound of fuel burned the greater
ihust be the heat wasted up the chimney.
Anybody familiar with the process of
combustion knows thai the lower the per-
centage of CO. the greater is the weight
of gas per pound of ftiel burned and
hence the greater must be the heat wast-
ed up the chimney; and conversely the
higher the percentage of CO.. within the
limits of complete combustion, the less
the weight of gas, and hence the less the
loss, and therefore high CO should and
does mean high efficiency and low CO:
means low efficiency. From this, how-
ever, it docs not follow that CO; is a
measure of boiler efficiency any more
than vacuum is a measure of engine effi-
ciency; none the less, hirh vacuum means

high efficiency and low vacuum means
low efficiency. Nor does it follow from
this that one engine running under a
vacuum of 22 inches may not show a
higher efficiency than another engine run-
ning under 2(5 inches of vacuum, or that
one boiler with an average of 10 per
cent, of CO: in the flue gas may not show
a higher efficiency than another boiler
with an average of 12 per cent, of CO:
in the flue gas. As maximum vacuum
means minimum waste of power due to
back pressure, so maximum CO:, consist-
ent with complete combustion, means
minimum waste of heat up the chimney;
neither by itself is a measure of effi-
ciency; both are important factors in at-
taining and maintaining efficiency. By
means of the vacuum gage one keeps
tabs on the spigot, while by means of the
CO: recorder the bunghole is controlled.
For example, if the boilers are working
with an efficiencv of 65 per cent., the en-
gine is using 85 per cent, of the steam
generated and the engine efficiency is
improved 5 per cent., a saving is effected
of 5 per cent, of 85 per cent, of 65 per
cent. = 2.76 per cent, on the coal used,
whereas if the boiler efficiency is in-
creased 5 per cent, by means of higher
CO: an actual saving of 5 per cent, is
made of the coal burned.

There is a great diversity of opinion
among practical men as to the percentage
of CO: that should he carried to get the
best results. Some find the higher the
CO: the better, up to 14 or even 15 per
cent.; others claim that when 10 per cent,
is exceeded the loss due to CO in the
flue gas becomes greater than the gain
due to the reduction in excess air. Both
statements are claimed to be based on
actual experience and one must accept
them as facts and search for the reason.

The writer has examined over 1200
gas analyses from various sources rang-
ing from 5 to 16 per cent, of CO.. These
analyses are from three difTerent plants.
Classifying them according to CO: and
their source. I find ( I I 115 analyses with
CO: running from 5 to 7 per cent.; of
these 115 analyses. 23 contain CO vary-
ing from O.I to 0.5 per cent. (2) Fron»
the same source I have 48 analyses run-
ning from 10 to 11.4 per cent, in CO:,
of which all but 13 contain CO. varying
from 0.1 to 2.1 per cent. This would
seem to prove the contention of those
who claim that when the CO exceeds 10
per cent, there is danger of losing more
in fuel (COt than is saved in heat. (3)
I also have several hundred analyses
from another source. 49 of these running
from 12 up to 13.8 per cent, of CO:.
Of these 4P analyses, only 10 show CO
which varies from 0.1 to 0.4 per cent.
This proves the contention of those who
claim that there is no danger of appreci-
able loss due to the presence of CO with
CO: up to 14 percent. (41 Again I have
over 200 analyses from a third source
var>'ing from 8 to I3.P per cent, in CO,.

848

POWER

December 5, 191 1

The lowest 25 samples vary from 8 to 10
per cent, in CO:, and all but 4 contain
CO varying from 0.1 to 0.4 per cent.
The 25 highest samples contain from 13
to 14 per cent, of CO^; all these show
CO from 0.1 to 0.8 per cent. All the
foregoing analyses were made from
average gas samples taken over periods
of from 6 to 10 hours.

(5) Further, I have 124 analyses made
from individual samples varying from
9.8 to 16.6 per cent, in C0=. Of these
124 samples, 69 contained CO, of which
constituent 0.3 per cent, occurred in the
sample showing the lowest CO: — viz.,
9.8 per cent — whereas the sample show-
ing 16.6 per cent, of CO. contained no
CO. The CO was distributed as follows
with reference to CO,: The one sample
with CO, below 10 per cent, contained
0.3 per cent, of CO. Out of eight
samples with CO, from 10 to 12 per
cent., 2 contained CO. Out of 25
samples with C0= from 12 to 14 per
cent., 5 contained CO. Out of 36 samples
with CO: 14 to 15 per cent., 24 contain-
ed CO. Out of 42 samples with CO;
15 to 16 per cent., 29 contained CO.
Fourteen samples contained 16 to 16.6
per cent. CO, and but seven of these
showed CO with only one case in which
CO exceeded 0.5 per cent.

It seems evident from the foregoing,
first, that low CO, is no guarantee against
loss through CO; second, that high CO,
may be obtained without great danger of
considerable fuel loss in the form of CO
if the proper conditions are maintained.
In this connection the fact should be
borne in mind that the fuel loss due to
CO decreases as the percentage of CO2
increases; that is, 0.5 per cent, of CO
occurring with 7 per cent, of CO: is
equivalent to 1 per cent, of CO occur-
ring with 14 per cent, of CO..

Appreciable amounts of CO should not
occur with CO, up to 14 to 15 per cent.
when burning anthracite coa!, nor with
CO: from 12 to 13 per cent, when burn-
ing bituminous coal. The higher the per-
centage of volatile matter, the lower the
percentage of CO; that can safely be
carried.

CO in conjunction with low CO, in
the flue is due to two causes: The first
and most prolific cause is air infiltration.
Large quantities of air are drawn in
through the pores of the orickwork,
through cracks in the boiler walls,
through warped and badly fitting cleaning
doors, diluting the real products of com-
bustion, in consequence of which the flue
gas shows low percentage of CO: — that
is, a great excess of air — while at the
same time the air supply to the fire is
insufficient for complete combustion. The
second cause is an uneven fire bed, too
much air passing through the thin or bare
spots while the thick portions receive an
insufficient supply. In every case where
CO occurs in conjunction with low CO:,

either one or both of these causes are
operative. Insufficient flame temperature
due to lack of combustion space may be
mentioned as a third cause of high CO
in the fiue gas. In a properly constructed
furnace, with a hot fire and an even coal
bed of the proper thickness, flue gas con-
taining 14 to 15 per cent, of CO: with
only traces of CO will be obtained when
burning anthracite coal provided the
boiler setting is quite tight. With low-
volatile bituminous coal 13 to 14 per cent,
of CO: should not be exceeded, and with
high-volatile coal it will be more diffi-
cult to have 13 per cent, of CO, and no
CO in the flue gas than 15 per cent, with
anthracite coal.

That it is possible to have very high
CO, with little or no CO appears evident
from the fact that of the 14 analyses of
flue gas referred to, running from 16 to
16.6 per cent, of CO,, 7 show no CO
and the average of this constituent in the
other 7 is only 0.33 per cent. In con-
trast to this are the 48 analyses running
from 10 to 11.4 per cent, of CO,, of
which only 13 are free from CO and the
remaining 39 show an average of 0.48
per cent, of CO.

This apparent anomaly is readily ex-
plained by the fact that the very high CO,
with low CO was obtained from anthra-
cite coal burned in a tight boiler setting;
whereas the comparatively low CO, and
higher CO w-ere obtained from an aver-
age boiler burning bituminous coal, with
air infiltration, probably exceeding 25
per cent, above that passing through the
grates. From this it is clear that if the
boiler had been tight the flue gas would
have shown CO, from 12.5 to 14.25 per
cent., or an average of 13.4 per cent, and
0.6 per cent. CO. Even with this high
average the CO should have been much
lower, indicating uneven firing or flame
contact with the cold surfaces of the
boiler before combustion was completed.

Below are results of 281 tests compiled
by Professor Breckenridge from the Gov-
ernment coal tests made at St. Louis dur-
ing and after the Louisiana Exposition,
grouped with relation to CO, and
efficiency:

.\verage

Number of

Average COg,

Etticiencv,

Group

Tests

Per Cent.

Per Cent.

;

■.i

n .->

5,1 .T

•J

L'l

7 6

62.0

:i

7.')

9..->

65.0

4

la

11.4

66.0

a

9

6..-)

56.0

6

62

S.6

64.2

7

10,4

65.0

.S

s

12.4

65.5

temperature are two other factors that
modify the relatioji between CO: and
over-all efficiency.

In Power of May 9, Frank T. Clark
publishes a very full report on seven
boiler tests using crude oil as fuel. I
have here arranged these tests showing
the relation of CO: to boiler efficiency.

r.F.L.\TIOX OF CO, TO BOILEIt

efficienh:y

Tempera-

Boiler

ture of

.\verage

Effi-

Escaping

Rate of

.No. of

CO,,

ciency

Gas,

Driving,

Test

Percent.

Percent.

Degrees

Per Cent.

1

12.2

81.1

385.3

72.7

2

1.3.3

82.4

409.1

109.4

3

13.4

82.8

397.5

94.0

4

14.3

83.3

. 406.2

109.2

5

14.2

81.5

429.0

132.8

fi

13.3

76.4

477.1

163 0

'

12.1

75.8

5;i7.5

195 . 5

That the efficiency in groups 4, 7 and 8
is considerably lower than it should have
been is undoubtedly due to bad furnace
conditions as well as bad firing, as is
indicated by the high CO cited in my
second group of analyses which were ob-
tained from the same source. Loss of
coal through the grate bars and stack

These tests show conclusively that
there is a true relation between CO: and
efficiency. The apparent discrepancy be-
tween Nos. 1 and 7 is readily accounted
for by noting the difference in the rate of
driving which resulted in a much higher
stack temperature and no doubt also in
a loss of fuel through incomplete com-
bustion. This also accounts for the dis-
crepancy between tests 2 and 3 as com-
pared with 6 and to a lesser degree also
between tests 4 and 5. But under similar
conditions, and within proper limits, in-
creased CO, means increased boiler effi-
ciency.

With the above statements of facts I
hope to have demonstrated, in a measure
at least, that high CO, means high effi-
ciency and low CO, means low efficiency.

That CO, cannot be a measure of boiler
efficiency must become evident from the
fact that CO: is a loss factor and in no
way enters into the calculation of boiler
efficiency. It is, however, an idex to
efficient firing, and if brought in continu-
ous evidence it serves as a guide to the
fireman by the aid of which he is enabled
to attain and maintain maximum combus-
tion efficiency. CO, and stack tempera-
ture are the two factors required to keep
tabs on the waste up the chimney, and
since these constitute 80 to 90 per cent,
of all the controllable heat losses, their
importance should attract more attention.

Draft is an important factor in rela-
tion to capacity as it controls the rate of
combustion, but it has no bearing on CO:
and fuel economy except as the latter is
affected by the rate of driving.

Illinois has produced more coal than
any other State except Pennsylvania,
the total tonnage since 1833, when coal
mining first began in the State, being
790,333,235 short tons, according to the
United States Geological Survey. Last
year the production was 45.900,246 tons
and the State stood third, Pennsylvania
producing 235,006,762 and West Virginia
61,671,019 tons.

December 5, 1911

POWER

Bristol's Ink Type Recorder

The Bristol Company, of Waterbury,
Conn., has recently developed and placed
on the market a frictionless ink-type re-
cording instrument which will accurately
record millivolts and is adaptable for
use as a recording electric pyrometer.
In external appearance it resembles the
Bristol patented sem.i-transparent smoked-
chart recorder which has been previously
described in Power.

The new instrument, which was pat-
ented by William H. Bristol on April 13,

tact with the source of marking fluid and
the chart.

Fig. 1 is an interior view showing the
galvanometer movement case hinged to
the back of the instrument and carrying
the inking pad in front of the recording
arm. Fig. 2 shows the sensitive electrical
movement swung to one side for con-

Indicator Reducing Motion

A new reducing motion recently brought
out by the C. & G. Cooper Company,
Mount Vernon, O., is illustrated herewith.
It is a combination crosshead-pin oiler
of the pendulum type with an indicator-
motion attachment which has the special

F]C. 1. Bristol In:; Type Recorder

F:g. 1. Reducing Rig Attached to Engine

1909, was designed to fill the demand
for a recorder in which the record is
made with ink. According to the manu-
facturer, it has been thoroughly tested

' __^

Bgch

j__^

r

1

1

^Iv^

1

f r

H

*>

J

1 H^--

A

^

Fig. 2. Electrical Movement Swung
TO One Side to Remove Chart

out in practical service for two years
past and is the result of several years of
study and experience with an original
patented design of the frictionless ink
recorder using a hinged electrical movc-
mcnf carrying a retaining receptacle for
marking fluid which extends over the
path of the recording tip and is provided
with means for periodically making con-

venience in removing the record and in-
serting a fresh chart. A capillary gold
tube open at both ends is carried at the
end of the recording arm at right angles
to the surface of the chart. The inking
pad is suspended from the case of the
electrical movment and is curved to cor-
respond with the arc covered by the mo-
tion of the end of the recording arm.

When the movement is swung back
into its operating position. Fig. I. the
recording arm can swing free, accommo-
dating itself to the position correspond-
ing to the delicate current which is to be
measured. The clock which revolves the
chart at the desired speed also auto-
matically presses the inking pad toward
the chart every 10 seconds, bringing one
end of the capillary tube into contact
with the chart, and the opposite end
simultaneously into contact with the ink-
ing pad. A fine dot of ink is left on the
chart and the capillary tube is replen-
ished with ink from the pad. The re-
cording arm thus carries a constant sup-
ply of ink. and its perfect balance, which
is very important, is always maintained.
The electrical movements used in these
recorders arc made especially for the
purpose by the Weston Electrical Instru-
ment Company.

Although the most important applica-
tions of these recording instruments have
been for pyrometers, they have also been
u<;cd for elcctrolvtic research, recording
voltmeters and recording shunt ammeters.

features of being an accurate reduction
of the piston's movements with variable
card-length control and a swivel pulley
over which the wire cord connects direct

B

Fig. 2. Detail of Reducing Motion

to the indicator drum, eliminating all
error.

This device is built on straight lines;
the motion for driving the indicator be-
comes an accurate reproduction of that
of the crosshcad to which the telescoping
oiler pipe or pendulum is attached. The
device is shown attached to an engine
in Fig. I.

850

POWER

December 5, 1911

Referring to Fig. 2, A is a small cross-
head, which is made to slide on two
parallel bars li by a yoke C which is held
to A by spring clamps for detachment
when not in use. The yoke C slides on the

of gravity had to be overcome in the
movement of the cam, due to the center
of gravity being above the shaft.

The new cam is almost exactly
balanced as regards discharge pres-

FiG. 3. Relative Size of Diagrams Obtainable

pipe D to compensate for the usual arc
motion. The pipe D is held rigid in the
collar E and swings pendulum fashion
on the stationary bar F. The hanger
frame G supports the parallel bars B and
is suspended by the pins H which pass
through the bar F and is held at any chosen
hight by a setscrew. The hollow swivel
post / is screwed into the engine-cross-
head pin to admit oil passing from the cup
above through the pipes D and J which
telescope over one another to correct for
the arc of the pendulum they form over
the straight line of the crosshead.

A wire cord K is attached to a re-
volvable pin in the small crosshead A
and passes over the swivel pulley
which is adjustable for angle and held
in place by a bracket to the hanger
frame G. The other end of the wire
cord K is fastened to the indicator drum
to which it imparts an exact proportional
motion of the engine's piston.

The device can be attached to any type
of reciprocating engine with very little
change in the lengths of pipes D and /
and the standard supporting the station-
ary bar F which must be rigid and free
from vibration. It also permits get-
ting an indicator card of any length from
3 to 4'_. inches without sacrificing its
accuracy through the adjustments nec-
essary, which can be made without stop-
ping. The limits of the card obtainable
are shown in Fig. 3.

Improved Rotrex Pump

The Rotrex pump, which is manufac-
tured by the C. H. NX'heeler Manufactur-
ing Company, Lehigh avenue and Eigh-
teenth street, Philadelphia, Penn.. has
recently been improved, the principal
difference from the earlier design being
that the shape of the vibrating cam
placed between the suction and the dis-
charge chambers has been changed.

In the new design the center of gravity
of the cam is located below the center
'of the shaft on which it swings, thus
taking advantage of the action of gravity
and producing a pendulum-like effect as
against the former cam, where the action

sure; that is, at the end of the revo-
lution and the moment of discharge, the
pressure on the cam, caused by the at-
mospheric discharge pressure plus the
vacuum underneath the cam, is directly
on the shaft and through the bearings,
as the projected area of the cam is equal-
ly located on both sides of the shaft

center. There is no tendency to thrust
the cam and rotor apart and the con-
struction equalizes and reduces the load
en the connecting rod driving the cam.
The new cam permits a smaller, lighter
yet more rigid construction of the pump,
and due to its better balance, enables the
pump to run at a high rotative speed.
The details are shown in Fig. 1.

In Fig. 2 is shown a Wheeler sur-
face-condensing equipment consisting of
a condenser, with a centrifugal circulat-
ing pump and an improved Rotrex vac-
uum pump, both mounted on the same
shaft and driven by the same engine.
There is also a centrifugal hotwell pump
which is used to lift the condensed steam
discharged by the air pump into an ele-
vated hotwell or feed-water heater. This
hotwell pump is a recent addition to the
equipment and is driven by a noiseless
chain belt.

Static Boiler Feed Regulator

The Static boiler-feed regulator con-
sists essentially of a diaphragm which
actuates the valve stem and disk of the

Fig. 1. Showing Improvement in Rotrex Pump

Fig. 2. New Centrifugal Hotwell Pump .Attached to Condenser Outfit

December 5, 1911

POWER

851

feed valve. These three parts are bolted
together as one. The controlling device
is composed of a small standpipe which
terminates at the set-water line within
the waterlevel chamber. The static pipe
is placed within a condenser pipe and
has at its upper end an open cup or res-
ervoir. This is shown in Fig. 1. The

boiler pressure is admitted to the top of
the standpipe. That side of the dia-
phragm to which the static pipe connects

rf

Fig. 1. Static Boiler-feed Regulator

will then be under boiler pressure plus
the head of water in the static pipe.

The chamber on the other side of the
diaphragm will always be under boiler
pressure. A difference of 2' _> pounds per
square inch on 50 square inches ef-
fective diaphragm area gives a lifting
force of 125 pounds with which to lift
both the balanced valve and load-
ing springs. When the bottom of the
condenser pipe becomes submerged as
the hight of the water in the boiler is
raised, the steam supply to the con-
denser pipe is sealed. As the steam con-
denses the water then rises into and fills
the condenser tube and the weight of
this water neutralizes the constant head
of the static pipe within. Under the
flooded condition of the condenser pipe
hydrostatic equilibrium is set up in the
diaphragm and the loading spring closes
the valve.

When the water falls below the set
water line, steam is admitted to the bot-
tom of the condenser tube and the col-
umn breaks and falls, which action re-
stores the lifting power of the diaphragm.

The regulator is protected from float-
ing foreign particles by a steam connec-
tion above and a water connection be-
low the water line.

The regulator is manufactured by the
Static Engineering Company, Arlington,
N. .1.

Static pipe passes down through the
condensing standpipe and connects to
the side of the diaphragm which is next
to the body of the feed valve. The op-
posite side of the diaphragm is connected
directly to the boiler.
■ The diaphragm is initially loaded by
springs and both diaphragm and springs
are constructed of a noncorrosive metal.

The valve stem connecting the dia-
phragm and valve disk passes through a
loosely packed gland which prevents leak-
age. The feed valve is placed with the
pump-line pressure side next to the dia-
phragm. The contents of the static pipe
will not escape into the valve body, but
any small leakage by the valve stem will
overflow at the top of the static pipe
and does not disturb the operation of
the regulator.

The reser\'oir at the top of the static
pipe is of a greater cubic area than the
displacement of the diaphragm stroke.
The diaphragm is designed to withstand
350 pounds pressure per square inch on
either side while open to the atmosphere
on the other.

The operation of the regulator depends
on the filling of the annular space be-
tween the inner and outer pipes of the
standpipe with water when the water in
the boiler is higher than the bottom of
the condenser pipe, and on the cmpiv-
ing of this space when the water falls
below the bottom of the condenser pipe.
When the water is low In the boiler the
condenser pipe is empty, as it is impos-
sible to keep wafer in the condenser pipe
after the end is uncovered, and full

1 \Ti,p !•; ^ItRVtrr

POWER

December 5. 191 1

._ '-^.-y*

Clian^ing Altcrnutinjr to

Direct Current

By C. a. Tupi'ER

There has been conspicuously observ-
able of late an almost universal tendency
to adopt alternating-current generating
apparatus and to extend the development
of alternating-current transmission. This
is found desirable not only for long dis-
tances but frequently for shorter ones
also. The use of direct-current motors
has, however, proved so necessary for
certain applications that a large percent-
age of the power generated is applied
through apparatus of this class. To make
possible the use of the two systems in
connection with each other, two general
types of machines have been developed.
These are known as the rotary converter
and the motor-generator. Each of them
is best suited for some particular kind
of work and the choice will depend upon
the engineering and economic considera-
tions entering into the problem.

From the fact, however, that there are
at present rotary-converter installations
of an aggregate capacity in the neighbor-
hood of 1,200,000 kilowatts, which is
more than that of any other type of cur-
rent changer, it would seem that the
rotary converter meets a greater variety
of requirements than does the motor-
generator. The writer found, during a
recent trip abroad, that the advantages
of the former are more generally recog-
nized in England and on the continent
than in this country, with greater de-
velopment of the practical features at-
tending its use. Fig. 1 shows one of the
latest types of rotary converter designed
and built by Vickers, Ltd., of Sheffield,
England.

The field c^ application and usefulness
of the rotary converter is, however, being
enlarged constantly in all parts of the
world. Its first use was probably in con-
nection with long transmission lines and
on interurban electric roads. Probably
the greater number of installations now
being made is in connection with railway
work.

At present, transmission in cities over
distances greater than two miles is usual-
ly effected by means of alternating cur-
rent and rotary-converter substations are
used to change over to direct current. In
large cities, especially, the load is very
Jieavy, and to distribute direct current
for any distance would require extremely
large cables or a large number of cables.

The placing of substations comparatively
close together, connecting them with the
central station by high-tension lines, and
then using short lines for feeders, helps
to keep down the line losses.

In various commercial lines outside of
central stations the rotary converter is
being considerably used. With the intro-

cover a large ground area, where ma-
chine tools are driven by direct-current
motors. Instead of generating and trans-
mitting direct current, alternating current
is used and changed to direct current ir
each shop by the use of a rotary con-
verter. This method reduces the multi-
plicity of large wires necessary with di-
rect current to transmit the large power
requirements. One such installation is
shown in Fig. 3.

One method which has been used to
show, roughly, the condition obtaining in
a rotary converter is to consider it as
being developed in several successive
steps. Taking the motor-generator set,
consisting of a synchronous motor and
a direct-current generator, assume that
the two armatures are brought side by

Fig. 1. Rotary Converter of 500 Kilowatts Capacity anp f i \i
Motor

auction of electricity into mining opera-
tions there has been a demand for a great
variety of electrical apparatus. Instead
of having isolated steam-engine installa-
tions modern practice tends toward a
central electrical plant serving the sev-
eral shafts and mills. The electric mule
has displaced the four-legged one in
mine haulage, and as a safeguard to life
direct current at low voltage has been
generally adopted for use. As this can-
not economically be transmitted a great
distance, a demand has developed for
alternating-current transmission to 250-
volt rotary converters. Many mines are
now equipped with installations of this
character; Fig. 2 illustrates a typical one.
Rotary converters have found consider-
able favor in manufacturing plants which

side on the same shaft within a single
field magnet. Then consider the further
simplification which results from placing
the two armature windings on the same
core; finally think of the effect of inter-
connecting the two armature windings or
using a single winding for both sets of
brushes, and an idea is obtained of what
happens in the armature winding of a
rotary converter.

Although the rotary converter has been
aptly described as a direct-current ma-
chine to which slip rings, connected to
suitable points on the armature, have
been added, it is essentially a single ma-
chine combining the features and char-
acteristics of a synchronous motor and
a direct-current generator. As the cur-
rent in the armature coils of a direct-

December 5, 191 1

POWER

853

current machine is actually alternating
before being changed at the commutator
brushes, the rotary converter can also
be considered as a direct-current ma-
chine receiving from an outside source
a current which has the same frequency
and pressure as that which the machine

plied by some other source; it can be
started by means of a small induction
motor (usually connected directly to the
shaft, as shown in Fig. ll, or it can be
started from the alternating-current side
as a motor by supplying a reduced volt-
age to the slip rings, as in the case of

Fig. 2. Rotary Converter at Substation of McKell Coal and Coke Company

would generate within its armature wind-
ing if driven at the rated speed.

Having determined the voltage normal-
ly desired on the direct-current side of
the machine, the line voltage is "stepped
down" in transformers so that the volt-
age at the brushes on the alternating-
current side has the proper ratio, which
is fixed, to the voltage of the direct-
current side. On a three-phase ma-
chine, which is the most common, the
alternating-current voltage Is about 63
per cent, of the direct-current voltage.
As an example of the relations existing
between the alternating and direct-cur-
rent side, consider a three-phase 50-
cycle machine, with eight field-magnet
poles, delivering direct current at 575
volts. This will receive alternating cur-
rent at about 360 volts and will run at
7.50 revolutions per minute. If the ma-
chine be driven as a direct-current motor,
at the same speed. .50-cycle alternating
Cfrrent can be delivered at the collector
rings at a voltage somewhat below ,360,
say about 3,50. Operating in this man-
ner the machine would be called an "in-
verted" rotary converter.

There are three ways in which rotary
converters may he started, and as the
alternating-current side of the machine
is the same as a synchronous motor it
must in all cases be brought into syn-
chronism with the supply current be-
fore being connected to the circuit. The
machine can he started from the direct-
current side as a motor if if is connected
to a general direct-current system sup-

some induction motors. This reduced
voltage is usually obtained from taps
on the transformers. When the machine
is started in the manner last mentioned
the field circuit must be opened. This
method has the advantage that the ma-

shaft. The motor in such a set may be
of either the induction or synchronous
type, depending on requirements. In
some cases the unit is started from the
direct-current side, but ordinarily it is
started from the alternating-current side
by means of an autotransformer, which
reduces the applied voltage at starting
and thereby prevents too great a rush
of current, or from taps on the second-
aries of the main transformers, if trans-
fonners are used between the motor and
the supply circuit.

As both the rotary converter and the
motor-generator accomplish the same re-
sult, that of changing alternating to di-
rect current, the choice of machines de-
pends largely on the nature of the load
on the direct-current side. Generally,
however, the rotary converter has certain
advantages which recommend it for use.
It has only one armature and conse-
quently offers less mechanical difficulty
than the motor-generator; it is also
cheaper in first cost than the motor-gen-
erator and usually more efficient, so that
the running charges are less. Consider-
ing the machine alone, the converter oc-
cupies less space than the motor-gen-
erator; this is offset, however, when the
motor-generator can be operated at the
line voltage without transformers.

One advantage of the rotary converter,
when used where the power load is a
rapidly fluctuating one, is that there is
no armature reaction and the "pull" on
the machine, therefore, can be varied
enormously. Instances are recorded of

(V CoNVimr.R '>t .^oii Know \n^ in ^X'
Aims Chalmehs. Co.mpany

chine automatically falls into synchron-
ism.

fn the other type of apparatus used
for ehangine aliernating info direct cur-
rent, the motor-eencrafor. the rotating
parts of both the motor and the gen-
erator are usually mounted on the same

temporary overloads equal to 300 per
cent., and the carr\-ing of 100 per cent,
overload for some time. Where the load
if of the lighting class rather than power,
the duration and heating efTcct of the
overload must necessarily be taken into
consideration.

854

One objection formerly offered to the
rotary converter was the fact that the
direct-current voltage was directly af-
fected by fluctuations in the alternating-
current voltage, but in modern installa-
tions of generating machinery there is
little fluctuation of voltage.

The question of the best type of ma-
chine to be emploj-ed in consideration of
the frequency of the alternating-current
system has often been discussed. With
25 cycles and other low frequencies, the
converter is usually employed. With 60
cycles and other high frequencies the
operation of converters is attended with
some difficulty, especially when the di-
rect-current voltage is above 500. Flash-
ing over and hunting have been the chief
troubles. In this country there have been
installed some 60-cycle rotary converters
for railway service but they are rapidly
being displaced, especially in sizes above
500 kilowatts. Some builders do not
recommend making high-frequency rotary
converters at all, and refuse to build any
of this frequency for 500 volts or above.
The accompanying table specifies what
is considered best in general practice;
although there are. of course, exceptional
cases where a deviation from this is
desirable.

POWER

.\LTERNATIXG-crRRENT

Freqcenci-

rent Voltage

25 Cycles

60 C.vcles

125
250
600

Motor-generator
Rotary converter
Rotary converter

Rotary converter
Rotary converter
Motor-generator

The rotary converter has already proved
so serviceable in so many different ways
that there is no question of its continued
and increasing use, but there is among
consumers of power generally an amaz-
ing lack of knowledge concerning its ad-
vantages.

Precautions again.st Electric
Shocks

The United States Bureau of Mines has
just issued a pamphlet designated
"Miners' Circular 5" which is devoted to
electrical accidents in mines and con-
tains some useful information as to the
conditions which favor accidents, com-
mon causes of them and means for pre-
venting them. The follo-ving precaution-
ary suggestions are taken from this
pamphlet.

The best way to avoid electric shocks
is to show due respect for the electric
current. Indifference to the dangers of
electricity does not indicate courage or
wisdom, but poor judgment and ignor-
ance. The fact that a man does not get
hurt when he is careless in handling
electric wires docs not prove that he is
cleverer than other men, but rather that
he is more fortunate. The worst feature
of such acts is the bad effect that they
have on those who see them or are told

about them. Those who know about
electrical apparatus and are employed to
handle and repair it should try to teach
others to be careful instead of encourag-
ing them to be careless.

The only sure ways to escape shocks
are to keep away from the trolley wire,
especially when carrying tools; to avoid
touching electrical machines unneces-
sarily; and to provide and use some
means of insulating the body when mak-
ing repairs on electrical apparatus. If
there is a way to cut off the current
from apparatus the current should be cut
off before the apparatus is handled. If
it is necessary to work on apparatus that
is carrying current, every precaution
should be taken to insulate the body from
the ground.

It is impossible to tell whether con-
ditions are safe unless the workman has
made them so himself. No one can tell
by merely looking at a motor whether or
not the parts that carry current have
come in contact with the frame of the
machine. A workman cannot be certain
whether the place where he must stand
to repair live apparatus will suflRciently
insulate his body from shock. The only
way for him to be safe is to provide
something suitable to stand on while
making repairs. In doing this he should
remember that dryness is the most desir-
able quality. Dry boards, free from nails,
are good for the purpose.

Rubber gloves or leather gloves in
good condition and without metallic fast-
enings will protect the body from shock.
If the rubber covering of gloves is worn
thin the gloves give almost no protection.
The same is true of leather gloves that
are damp with water or sweat. Rubber
boots without nails in the soles or heels
are good protection when new, but if the
soles are worn or cracked, their insulat-
ing value is doubtful.

The position of the body is an im-
portant matter in handling apparatus that
is carrxing current. If a man has merely
to make some adjustment he should use
but one hand, if possible. He should
also tr>' to place his body so that the in-
voluntary recoil from a possible shock
will remove his hands from the apparatus
instead of causing them to grasp it.

The use of rubber tape on the handles
of pliers, screwdrivers, and wrenches can-
not be depended on unless the tape has
been freshly and carefully applied. Rub-
ber coverings for the handles of such
tools are a protection if the coverings are
new and in good condition, but even then
the chances are great of touching the
hand or the fingers to an uncovered part.
Insulated tools should not be trusted to
give entire protection.

There is one practice that cannot be
condemned too severely, and that is the
wilful giving of electrical shocks to
others. This may be done impulsively
or may be deliberately planned, but it is
always dangerous.

December 5. 191 1

CORRESPOxVDExNCE

Mr. Fox's Alternator Trouble
In the October 31 issue, Charles Fox,
of Bay Ridge, O., describes trouble he'
has had with two alternators. I would
suggest that the two machines are prob-
ably not exactly in synchronism as re-
gards the piston positions of the engines.
There is always more or less uneven-
ness in the rotative effort of any engine,
regardless of the size of the flywheel,'
and it may be that these two machines
are not so synchronized that the rotative
efforts of the two engines are distributed
alike throughout each revolution. I think
it would be w^ell worth while for Mr.
Fox to try to get the two machines into
step as regards the crank effort, and
see if his troubles do not disappear.
Henry D. Jackson.
Boston, Mass.

My opinion of the trouble in parallel-
ing alternators, described in the October
31 issue by Charles Fox, is that differ-
ence in engine regulation causes the
trouble. Unless the regulation is exactly
the same on the two engines, there will
be only one load at which the alternators
will divide the load smoothly without
cross currents. At any greater load, the
engine which regulates more closely will
be tr\-ing to run faster than its mate;
at any lesser load, the close-regulating
engine will try to lag behind its mate.
In both cases there will be surges of
cross currents.

We had the same trouble Mr. Fox
describes with two two-phase machines
until we discovered that the two engines
had different speed drops from no load
to full load. When this was corrected
the trouble disappeared.

David S.mith.
Wellesley, Mass.

Treatment of Commutator
Brushes

Replying to the recent letter from
Manila! K. Desai, advising the use of
kerosene for lubricating carbon brushes.
I find that brushes soaked in kerosene
will be softer and that the carbon will
rub off on the commutator, covering it
with smut and causing poor contact with
the brushes.

I have had verv' good results on a 125-
volt, 112-ampere direct-current generator
by soaking the brushes in machine oil
for 24 hours, then wiping them clean and
allowing them to dry for six or seven
days. I find that it hardens them and
does not allow the carbon dust to rub off,
which makes them wear longer and make
better contact on the commutator: more-
over, the sparking has entirely ceased.
Herbert Hill.

Middle Falls. N. Y.

December 5, 191 1

POWER

855

Improved Rathbun Valve
Gear

The accompanying engravings illus-
trate the improved valve gear now used
on the gas engines built by the Rathbun-
Jones Engineering Company, of Toledo.
O. The main features of the engine
other than the valve gear are well known
and have not been materially changed.
The valves are actuated by individual ec-
centrics instead of by the cam and roller
arrangement previously used and the
rocker arms have exactly the same fea-
tures of operation which characterize
the well known wiper cam levers used

block. The function of the links is
merely to keep the various parts in line.
The rolling motion of the rocker arm
along the face of the anvil is obtained by
making the curve of the anvil face of a

Cost of . Pow er Produced by
an Oil Engine*

By F. p. Pfleghar and E. H. Lockwood

A horizontal De La Vergne oil engine
of 125 horsepower rating was installed
by the Pfleghar Hardware Specialty Com-
pany in 1907 to drive a 220-volt direct-
current generator supplying current to
motors in the shops. The engine cylin-
der is 27 inches in diameter and the
stroke 33 inches. The fuel is petroleum
fuel oil, costing 3^4 cents per gallon, de-
livered. For two years the oil engine
gave considerable trouble, due primarily
to the manner of connecting the exhaust

en many large gas engines, but are of
simpler construction. There is only one
rocker arm for each valve and that ful-
crums on the face of a curved anvil A,
Fig. 1, which is stationary. When the
push rod starts upward, the rocker arm
fulcrums acain!;t the extreme left-hand
end of the anvil, giving the push rod
large leverage over the valve. Continued
motion of the push rod, however, pro-
duces a son of rolling motion at the
face of the rocker arm which transfers
the fulcrum rapidly to the right-hand
end of the hearing surface of the anvil,
thereby reducing the leverage and ac-
celerating the motion of the valve, which,
of course, is a desirable feature.

The end R of the rocker arm is connected
by a pair of links with the pivot pin C,
which is mounted in an extension of the
anvil block; the links straddle the ^nvil

Fig. 2. Eccentric and Push-rod Con-
nection

clifferenf radius from that of the curve
of the rocker face, the radius of the
latter curve being the longer of the two.

Fig. 2 illustrates the connections be-
tween the valve-gear shaft and the push
rod. An ordinary eccentric is mounted
on the valve-Rcar shaft and the arm of
the eccentric strap is pivoted to a tubular
crnsshead which slides in a cylindrical
guide. The push rod is attached to the
upper end of the crnsshcad Mock.

Fie. 3 shows the complete valve gear
in position on the engine.

Fig. 3. Complete Valve Gear

pipe and to the cooling-water connec-
tions to the piston. During the summer
of 1010 extensive repairs were made,
resulting in greatly improved perform-
ance, and it is now considered as re-
liable as a steam engine. A few months
after installation the engine was care-
fully tested for output and fuel consump-
tion, and found to be ven,' economical
of fuel.

The daily cost of operation of the en-
gine is aprrnximatcly as follows, the nm-
ning time being 10 hours, and the average
output on horsepower;

•r'npT roml nt a tnopllnif of tlin Amnrtrnn
H<ir|i.|v "f Mnrlinnlrnl i;ni:ln'nr«. Iiflil Tin-
rfmlni- \T,. Ill Npw llnvpti. •'onn.

POWER

December 5, 191 1

Kuel $7.:.S

Labor (one man, half tiinei 1-50

Oil, waste, coolins walci-, impairs... l.Ol)

Cost of operation per year of 300

days $2!)04.00

Cost of operation, per year per horse-
power :i2.:io

Cost per horsepower-lion r l.oKc.

I'lXKP ClIAIlliKS

Ctsi of enRlnc, $0000: 10 per i-enl.

of eost .flloO.Oii

Cost of heatlns boiler, $1i)0ii; 111 per

cent, of cost of heating holler... loii.iio
Insurance and taxes i:."io.oo

.$0.->0.OII
Cost of li\ed charges i)cr yar per

horsepower .$l(l..-|.-i

Tiilal cost per year |)er horsepower 4i'..S.'">

Comparison with Steam Power

Owing to the troubles experienced in
the beginning, a lOO-horsepower steam
engine and boiler were installed. The
operating costs per day for the steam
plant, delivering 90 horsepower, were as
follows:

Fuel Sll.nO

Labor (one man. full lime) X.OO

Oil and waste 1.00

.f 15.90
Cost of- operation per year of 300

days .'i;4770.00

Cost of operation per year per horse-
power .-.3.00

Cost per horsepower-hour 17%c.

Kl.XKI) ClIAKIJKS

On cost of engine and generator..-.. ^S.'iO.OO

On cost of boiler : 200.00

Repairs, insurance and taxes 2oO.no

.$S00.fHI

Fixed charges per year per h<u-se-

power ."PV-Oo

Total cost per year per horsepower lit. 00
SC.MMARY PER YI-'.AI!

Oil Sceam

i:n-ini' I'ianl
Operating cost per year per

horsepower $32.30 $.->3.nn

Fixed charges per year i)er

horseiiower '. lO.o.i 8.90

Totals .•<J2.S.-, .$01.90

LETTERS

Mr. Caton's Diesel Engine
Diagram

A feature of the Diesel-engine diagram
submitted by William R. Caton in Power
for October 31 (Fig. 1 herewith I will
doubtless puzzle some readers who use

500
400-

which has considerable stem, the lower
one of these screws has to be adjusted
with a screwdriver from the lower end
of the piston, but because of its incon-
spicuous position it is likely to be over-
looked when the indicator is adjusted.
Failure to tighten it makes possible a mo-
tion of the piston (and tracing point)
which is not controlled by the spring,
but only by the weight of the parts.

When the pressure in the cylinder is
greater than atmospheric, the lower screw
is pressed up against the ball on the

piston draws in atmospheric air, the dia-
gram should start at the atmospheric
line; the zero should therefore be placed
at A [Fig. 4]. Suction continues to the
point B where the compression is sup-
posed to start, and the line of the dia-
gram during this period is a normal one
for a full-pressure diagram. From the
point B to the point C there does not
seem to be any compression worth speak-
ing of, but beyond this point the line
rises sharply; this can be caused by a
retarded closing of the inlet valve.

From C to D the compression curve is
practically normal, but beyond D some-
thing is wrong with the diagram; it does
not show the usual short horizontal line
caused by the gradual injection and com-
bustion of fuel. The sudden drop in
pressure seems to indicate that the cyl-
inder from which the diagram was taken
was doing very little work, only enough
oil having been fed to round the peak of
the diagram.

The shape of the toe is also abnormal.
This may be due to a badly worn ex-
haust-valve cam which opened the valve

Fig. 4. Mr. Vanderfeer's Diagram

spring and the upper portion of the dia-
gram may be made very accurately.
When, however, the pressure falls to at-
mosphere, as it did in Mr. Caton's dia-
gram at about a quarter of the exhaust
stroke, the piston drops until the upper
screw rests on the ball, as shown in Fig.
2, which position it maintains until pushed
up by the increase of pressure during
the compression stroke.

Fig. 3, taken from a 9':4xl6-inch gaso-
lene engine running at 225 revolutions
per minute, shows a case where the ex-
haust pressure is above the atmosphere
during the whole exhaust stroke, the pis-

so slowly that the pressure remained
practically constant from £ to F. At the
point F, the valve seems to have been
opened full, allowing the gases to es-
cape in the regular way. at about at-
mospheric pressure.

H. Vanderfeer.
Hoboken. N. J.

The Diesel-engine diagram submitted
by Mr. Caton in the issue of October 31
is misleading because it has two at-
mospheric lines. This indicates that the
indicator has lost motion, either from the
spring not having been tight at the time
the diagram was taken or because the
joints of the pencil movement are worn.
The effect of this is to diminish the hight

Maximum Gage Pressure 540 lb.
Mean Effective Pressure 60 lb.

Fic. 1. Mr. Caton's Diagram

Fig. 3. Mr. .Munro's Diagram

indicators on which such a thing could
not happen. I refer to the double at-
mospheric line with the cross lines be-
tween them. In some makes of indi-
cators the piston is attached to the spring
by a sort of ball-and-socket joint, a
ball at the lower end of the spring be-
ing held between two cup-shaped screws.
In a gas-engine indicator, the piston of

ton dropping at the beginning of the suc-
tion stroke.

G. W. Munro.
LaFayette, Ind.

The only explanation of Mr. Caton's
Diesel-engine diagram, it seems to me, is
that the pressure scale is not drawn in
the right place. As every Diesel-engine

of the diagram during expansion and to
raise the whole bottom of the diagram
during the compression by the distance
apart of the two atmospheric lines. The
diagram is thereby so distorted as to be
valueless as an indication of what the
engine is doing.

Arthur J. Frith
Chicago, 111.

December 5, 1911

P O W E R

Heating and Ventilation

Heating Plant of the New
York Public Libran'

By a. D. Blake

About three years ago, when the con-
struction of the New York Public
Library was well under way, the ques-
tion of furnishing light and power
came up for consideration. For a time
a lively war was waged between the ad-
herents of central-station service and
those wishing an independent generating
plant. The New York Edison Company

sij^ned to nurcly take care of the radia-
tion through the outside walls, while the
latter changes the air at stated intervals.

Emerior View of I.B'^v'-

In heating, the Paul system of direct
radiation is employed, the radiators being
placed along the outside walls of the
looms, taking exhaust steam from the
engines and having a vacuum on the air
valves. .About 28,500 square feet of
heating surface is thus supplied. A John-
ston system of thermostatic control auto-
matically maintains the desired room
temperature.

The Ventilating System

The ventilating system consists of two
divisions, the air supply and the exhaust.
For the former, fresh air is drawn in
from the courtyard, is filtered in passing
through cheesecloth screens and is then
passed over tempering coils located in
the basement. These coils utilize ex-
haust steam from the engines and
temper the air to the desired room tem-
perature. On account of the bindings on
the books it is desirable that the air be
maintained at a certain humidity, and for
this purpose moisture pans are placed at
the bottom of the coils. After leaving the
coils the tempered air is handled by three
12x6- foot and one 12x5- foot motor-driven
Murtevant fans (each 12xti-foot fan
capable of handling about 75,000 cubic
feet of air per minute) and is distributed

was ready to furnish current for light and
power at a maximum yearly cost of
S25.000 if the consumption did not ex-
ceed 833,333 kilowatt-hours, and .S21.t500
if the consumption did not exceed 675,-
000 kilowatt-hours.

The heating of the building, however,
proved to be the determining factor, and
those in authority finally decided that an
independent generating plant supphing
exhaust steam to the heating system
would be more economical than central-
station service with a separate heatinu
plant.

The total cost of the plant, exclusive of
the wiring and healing ducts and pipes
throughout the building, was Sin2.<H)ii.

Owing to the size of the building, rep-
resenting a volumetric content of approx-
imately 6.7.50,000 cubic feet, its exposed
position and its many windows, a verv
interesting heating and veniiUtine prob-
lem was involved, and its solution form'
one of the interesring features of the
plant. The system was laid out on the
basis of maintaining a room temperature
of 70 degrees during zero weather.
The Hf.atinc System

The heating system is distinct from the
ventilating system, the former being de-

Y

' 1

\-4

:'i'

'-

^ j

4

^

-•1

t/

H-AiR Intake, Tempering Cons anh Fans

858

through a system of ducts to the various
rooms. Fig. 2 shows the arrangement
of fans, filters and tempering coils and
Fig. 3 IS a view looking down the row
of fans.

In the reading rooms the general scheme
IS to blow in this tempered air at or near
the ceiling and to e.xhaust the impure air
rr.zr the base. For the latter purpose a
group of exhaust fans are located in the
attic. A separate fan in the basement
handles the ventilation of the engine
room. In the stack rooms the supply and

P O W E R

December 5. 1911

Fig. 3. Row of M.^in Supply Fans

exhaust air ducts are contained in the
ends of the book stacks, the supply being
at the top and the exhaust at the bottom.
The system was designed with a view
to changing the air three times an hour in
the main reading room and two and one-

BOILERS

^alf times an hour in the stack rooms.

-the other rooms throughout the huildin-

are changed six times an hour. It is also

arranged in units so that anv parts of the

December 5, 1911

POWER

859

building not in use may be cut off from
the heating service.

Fig. 4. No superheat is used nor are

economizers employed. The feed water

is heated in a Berryman heater and is

supplied to the boilers by two 7'jx4'jX

10-inch Blake pumps. A section through
sure by six 250- and two 240-horsepower the boiler room is shown in Fig. 7 and dumped into this directly from wagons in
hand-fired Babcock & Wilcox boilers, set Fig. 5 is a plan of the boiler and engine the street above and is extracted as need-
in batteries of two each, as shown in rooms. ed through doors opposite each boiler. A

Boiler Plant
Steam is furnished at 135 pounds pres-

The method of handling the coal and
ashes deserves special mention. Along
the front of the boiler room and extend-
ing out under the sidewalk is a coal
pocket of 150 tons capacity. Coal is

Fig. G. Engine Room

.Conveyer

Fic. 7. Section through Boiler Room

second bunker is located over the boilers;
this is of fiOO tons capacity and discharg-
es through hoppers in the front of each
boiler to a traveling scales with chute
attached. Coal for this bunker is dump-
ed from the wagons into a weighing bin
(see Fig. 5), from which it is discharged
onto an endless bucket conveyer which
passes under the row of boilers and then
up over the coal bunker. This conveyer
is also used for elevating the ashes from
the hoppers under the ashpits and dis-
charging either to an ash-storage bin or
to the wagons direct.

The main 14-inch steam header feeds a
12-inch supply main to the engines.
An auxiliary 8-inch steam loop is provided
for use in case the main steam linp is
shut down for repairs or any other pur-
pose. The main exhaust from the en-
gines is Ifi inches. Vanstonc joints are
used on all high-pressure piping over 5
inches in diameter.

Engines and Generators

Electricity for light and power is
furnished by four units, two of 500 kilo-
watts and two of 200 kilowatts capacity,
each consisting of a 2.'iO-volt Westing-
house direct-current generator, direct

860

POWER

December 5. 1911

connected to a single-cylinder, noncon-
densing Fitchburg engine, the larger
ones running at 100 revolutions per
minute and the smaller at 150. The en-
gines exhaust into the heating system.
As will be seen by reference to Figs. 5 and
6, the engine-room equipment is arranged
in duplicate, one 500- and one 200-kilo-
watt unit being able to handle the load.
In fact, during a large part of the time
the smaller unit is able to carry the load.
A 14 1 -cell 800-anipere-hour storage bat-
tery of the chloride type supplies current
for the night load after the reading rooms
arc closed. At such times live steam is
passed through a reducing valve into the
heating system, although in moderate
weather the building remains reasonably
warm and little live steam has to be
used

Operation

It has been found convenient in actual
operation to modify the use of the venti-
lating system from that originally de-
termined upon. With the intake wide
open and all the supply fans running, it
was found that the tempering coils acted
like a large condenser and that the en-
gines carrying the usual load could not
supply anywhere near the amount of ex-
haust steam needed; hence a large
amount of additional live steam was nec-
essary. Incidentally it was observed
that with the fans shut down, the cold-air
intake only partly open and the exhaust
steam passing through the coils, a suffi-
cient circulation was set up to keep the
air in the rooms pure. The exhaust fans
are kept in operation, of course, and
greatly assist in this circulation. This
practice has thus far been followed for a
greater part of the time.

It is planned to use carbon-filament
lamps throughout the building during the
winter time, first, because of their rela-
tively low cost, and, second, because the
load is needed in order to supply the
necessary exhaust steam. In the summer
time tungsten lamps will be used.

According to the operating figurel,
electrical energy was produced last sum-
mer, when the exhaust steam was going
to waste, for about 2\k cents per
kilowatt-hour, and according to the pres-
end indications the cost per kilowatt-hour
lor the winter months will average close
to 1 cent.

Of course, the plant has not been run-
ning long enough to obtain conclusive
figures as to the cost of heating and the
production of electrical energy at all
seasons. However, last winter the heat-
ing plant was run alone without the en-
gines, the high-pressure steam being pas-
sed through the reducing valve before
supplying the heating system. The cost
of heating under these conditions, which
was approximately SlOO a day (operating
cost alone) during the winter months,
will form an interesting comparison with

the total cost of operating the plant dur-
ing the coming season.

The electrical features of the plant
were designed by Pattison Bros, and the
heating and ventilating by Nygren,
Tenney & Ohmes. The superintendent
and consulting engineer is John H.
Fedeler and the chief engineer is
Louis Alt, who for a number of years
v.as chief engineer of the old Astor
Library.

LETTERS

Continuous vs. Iiitennittent
Heating

The foreword in the November 7 num-
ber of Power raised some very interest-
ing questions in my mind, the most im-
portant perhaps being: Is it more eco-
nomical to run the heating plant in a
school building continuously? The
amount of heat required for any build-
ing, of course, is equal to that which
leaves the building, I think everyone
will concede that more heat leaves a
building when it is up to 70 degrees than
when it is at 55 degrees. The question
then becomes: Can this extra loss, when
the building is up to 70 degrees, be com-
pensated for in any way?

I mention the temperature of 55 de-
grees because it has been my observation
that, when steam is turned off for the
night, the temperature will at first drop
rapidly, but by the time it has dropped
10 or 15 degrees, it will drop very slowly.
This is evidently because, after dropping
this much, the heat which passes from
the walls, floors and furniture to the air
of the rooms almost compensates for
that which passes from the rooms to the
outside. Much of the heat leaves a build-
ing through the windows and the solid
materials of a large building store a
large amount of heat.

My experience has also been that
bringing the temperature back to 70 de-
grees in a few hours before the school
session begins requires no extra boiler
capacity. This is because, until the ses-
sion begins, no air is needed for ventila-
tion, and when air for ventilation is sup-
plied, much more heat is needed to main-
tain a constant temperature.

I have never handled a low-pressure
boiler, but I can see no reason why as
much heat and as great a percentage of
the total amount of heat cannot be trans-
ferred from the furnace gases to the
water in a low-pressure as in a high-
pressure boiler. The volume of steam
from a low-pressure boiler is much
greater, which fact leads me to ask the
following: As usually installed, does the
amount of liberating surface, the size of
the steam pipe, or anything else, on a
low-pressure boiler limit the boiler to
less than a boiler horsepower from, say,
10 square feet of heating surface?

High pressure — that is, some surplus

pressure — is an advantage in handling
suddenly varying or intermittent loads,
and is also an advantage to the fireman
who wants to throw in a large fire and
then leave the boiler for a long time;
but is it any advantage, in heating, in
handling a gradually vary-ing load?

H. H. Hastings.
St. Louis. Mo.

The following data, obtained by W. C.
Powell, engineer of the Waterbur>' Man-
ufacturing Company, of Waterbury,
Conn., some years ago, have a direct
bearing on Mr. Hastings' questions. The
engines were operated condensing from
Manning boilers under very high pres-
sure. The heating was done by means
of horizontal tubular boilers operated at
50 pounds pressure, so that the system
was entirely distinct and separate from
the power boilers. Mr. Powell's report
runs as follows:

'"We have a factory containing 20,710
square feet of radiating surface for heat-
ing purposes, about 20,000 of which has
been in use for the past five weeks, dur-
ing which time we have kept a record of
the coal burned and the temperature of
the outside atmosphere. According to
our record, when the thermometer aver-
aged 42 degrees during the day we re-
quired 4200 pounds of coal per 24 hours
and when it averaged 22 degrees we re-
quired 8100 pounds of coal. In our
horizontal tubular boilers we extract 8500
heat units per pound of coal, which
amount is transferred to the hot water,
the balance of the heat in the coal being
lost.

"The average temperature for the five
weeks being 33 degrees and the average
coal consumption 5400 pounds, we will
consider these conditions constant, as it
will materially lessen the complication
of figures, and give an approximate re-
sult sufficiently close to guide us in operat-
ing this system. Multiplying the pounds
of coal by the heat extracted per pound.

5400 \ 8500 — 45.900,000 B.t.u.
per 24 hours were obtained, or 1.912,500
heat units per hour' radiation from the
system, which also represents the radia-
tion from the factory to the outside at-
mosphere under these conditions. If the
factory were shut down as far as heating
is concerned. 19.125.000 heat units would
be radiated to the outside between 6
p.m. and 4 a.m., and

10 X 1.912.500 - 19.125,000 B.t.u.
would be saved.

"In the morning we would have to
raise the temperature of the factor\' to
70 degrees again in three hours. When
the source of heat is shut off the radia-
tion diminishes as the temperature in-
side decreases. The air space in the
factory is approximately 1,600.000 cubic
feet and were the building empty, the
temperature would go down quite rapid-
ly as the air would contain 2,011,730
heat units. We must consider that the

December 5, 1911

POWER

861

contents of the buildings have to give
up their heat as the inside ter.perature
diminishes. The fire-extinguisher pipes
are full of water at 70 degrees and must
radiate their heat to the factory, as well
as the hot water in the heating pipes, as
soon as the temperature begins to fall.
The same is true of all machinery, tools
and metal of all description. The wood-
work, floors and posts and all contents
must give up their heat which tends to
keep the temperature up inside, as an
immense amount is stored up in this
manner. It also has to be replaced be-
fore the room is at 70 degrees again.

"It is reasonable to assume with a
difference of 37 degrees between the in-
side and outside, that the inside tem-
perature will not fall below 60 degrees
in the factory in 10 hours' time between
6 p.m. and 4 a.m., and this has been
demonstrated by observation many times.
To ascertain what amount of heat has
been stored up in the contents of the
building and has radiated, it will be nec-
essary to know the amount of coal or
steam required to raise the temperature
from 60 to 70 degrees. This we have
found by letting the temperature of the
factory fall to 60 degrees and weighing
the coal required to raise it to 70 degrees.
This has been found to be 3000 pounds,
which, multiplied by 8500, equals 25,500,-
000 B.t.u.

"Had we kept the factory at 70 degrees
temperature all night we would have
burned 2925 pounds of coal to furnish
the loss by radiation for 13 hours from
6 p.m. to 7 a.m. This therefore proves
that there is no saving by shutting off
the heating system at 6 p.m. and then
overtaxing it early in the morning. The
difference in coal in favor of operating
all night is 75 pounds, or 2'< per cent."

Taking 34 pounds of water per boiler
horsepower and 1000 B.t.u. per pound of
steam, the boiler horsepower required to
be operated continuously would be,

2925 X 8soo

-^-^ = S"-1 liortcpOiecr

I? X 34.000

If operated for three hours, the required

capacity would be

^rioo X 8500 ,

' — ^250 horse pourr

J X M.ooo

or four times the horsepower required

when run continuously.

Ira N. Evans.
New York City.

A Water I Iratcr IVoblcm
Having been called upon to make
some arrangement for furnishing warm,
not hot, water for the office force in the
factory where I have charge of the en-
gine and boilers, I commenced to for-
mulate some plan that would he efficient,
simple and yet fill the requirements.

First we considered a tank with a
steam coil inside, but soon realized thai
the water, unless used as fast as heated,
would soon get nearly as hot as the

steam; also, a steam-reducing valve
would be necessary and some means,
such as a trap, would have to be pro-
vided to save the condensation. This
meant too much complication and the
method was discarded.

Thermostatic control, in order to keep
the water at a medium temperature, was
next considered, but the disadvantages
were about as numerous as in the first
case.

An arrangement for heating the water
with gas was also given some attention,
but the amount of gas consumed with
the problem of keeping the "pilot" burn-
ing at all times turned us against it.

Another plan was to draw the water
directly from the boiler-feed line. This

In the sketch, B represents the cold-
water supply to the tank. A small relief
valve C is installed on the water supply
to protect the tank against the expansion
of the water.

Pipe D is the warm-water outlet lead-
ing to the toilet rooms. To save needless
waste of water, the tank is placed as
near the toilet room as convenient, so
that only a small amount of water needs
to be drawn before the warm water in
the tank is available.

N. C. Rice.

Springfield. Mass.

A Homemade Siphon

Where there is danger of the sewer
backing up into the pit containing the

Warm-water Tank

was quickly decided against, for the
water would be too warm, also more or
less unclean as it came from the heating
system.

The plan shown in the accompanying
illustration was finally adopted. As may
be seen in the illustration an ordinary
12x30-inch galvanized-iron expansion
tank was provided with openings in each
end for I -inch pipe. A >4-inch brass
pipe A was run through the tank, one
end of the pipe being threaded into a
'ixl-inch bushing which was screwed
into one end of the tank. The other
end of the pipe, in order to allow for
contraction and expansion, was packed
with soft packing and held in place by
a check nut screwed on the pipe.

One end of this pipe was connected to
the boiler-feed line after it left the feed-
water heater. A valve was placed on
the line so that the amount of hot water
passing through the pipe in the tank
could be regulated according to the de-
sired temperature and quantity of warm
water required in the office.

The outlet end of the pipe was con-
nected to the pump receiver. With these
connections there is very little loss of
heat, for only enough water is shunted
through the tank to warm up the office
supply to the desired temperature.

A valve is placed in the outlet and is
kept wide open so as to have no ap-
preciable pressure in pipe A. While with
this arrangement the tank can be heated
only when the pump is running, the tank
is of ample capacity so that enough water
is in storage to supply the demands of
the office force when the pump is not
in action.

HoME.MADE Siphon

pump and receiver on the heating sys-
tem, a homemade siphon can be installed
at very small expense. Take an 8-inch
length of ' J -inch pipe with one end
tapered for I inch. Cut a running thread
on the tapered end, and screw it into a
l'4x''>-inch bushing so that the nozzle
will extend into the discharge pipe on
the opposite end of the tee about 's
inch. On the other end of the 8-inch
piece of pipe cut a standard thread for
an elbow so that a globe valve may be
inserted in the line to regulate the supply
of steam to the siphon. It is also nec-
essary to have a union in the line placed
between the valve and the siphon.

Lewis A. Danner.
Chicago, III.

Measurement of Air Velocities

Referring to the article by F. G.
Heckler in Power of August 29, in Fig.
2 he illustrates an arrangement of Pitot
tubes whereby he alleges he can secure
accurate readings of the velocity of air
passing through the pipe. His readings
would be inaccurate if made with the
static tube at A projecting into the pipe
as shown. To determine the static pres-
sure the connection must not project but
must be flush with the inner wall of the
pipe.

A. H. Anofrson.

Chicago. III.

The first frcichl steamer propelled by
Diesel oil engines to cross the Atlantic
reccntlv arrived at Montreal. Canada. The
voyage was made from the Tvnr in the
St. Lawrence in 26 days.

?62

POWER

December 5, 1911

Boiler fc^xplosion in England
Kills and Injures Many

By the explosion of a boiler in the oil-
cake mills of J. Bibby & Sons, at Liver-
pool, England, on November 24, thirty-
three workmen were killed and upward
of 100 others were injured.

At the time of going to press only very
meager details could be obtained and it
was impossible to ascertain the cause
for the explosion.

Nearly 400 workers were in the build-
ing at the time and everyone was thrown
to the ground by the violence of the ex-
plosion. It is reported that many in the
vicinity of the boiler room had their
legs literally torn off, and their mangled
bodies fell into the adjoining streets to-
gether with heavy showers of brick and
debris.

Following the accident the whole build-
ing burst into flames and was soon blaz-
ing fiercely.

A special representative is getting the
story for Power and the details will be
published as soon as available.

Fatal Piping Accident at
Scranton

A most unfortunate accident occurred
at the Scranton Electric Company's plant,
Scranton, Penn., on Sunday morning, No-
vember 19, which resulted in the death
of two men and the serious scalding of
three others.

These men were employed by the New
England Engineering Company and were
engaged in making extensions to a 22-
inch exhaust-steam pipe. This pipe was
coupled to one of the new reciprocating
engines and was connected to a main
heating pipe which was run to the busi-
ness section of the city and furnished
steam for commercial heating. The ex-
haust pipe ended with a 22-inch tee, the
outer end of which was capped with a
blank flange.

It was the intention of the men to se-
cure a nipple to the tee and extend the
pipe to a second engine with connec-
tions so arranged that either or both en-
gines could exhaust into the heating main
or one could exhaust into the heating
main and the other to the atmospheric-
exhaust pipe. The pipe was in the base-
inent and the tee came in a narrow space
between the engine foundation and the
basement wall. This made it almost im-
possible for the men to escape when
the flange blew off.

Just why the men should remove the
flange from the end of the tee while
steam was on the pipe, is not known. The
officials of both the Scranton Electric
Company and the New England Engi-
neering Company are reticent and there-
fore no information can be obtained from
'them. It has been ascertained that a
live-steam pressure of about 8 pounds

per square inch was on the line at the
time of the accident as the engine con-
nected to the exhaust pipe was not in
operation, the live-steam being used to
do the necessary heating.

Owing to some misunderstanding or
not knowing that the steam was not turned
off, the men doing the work removed the
nuts from the Hanged bolts and the blank
flange was then blown off.

It is rumored that the men were told
that the line was dead, but this cannot
be verified. From newspaper reports, it
is stated that Inspector Flint, of the-
boiler-inspection department, declares
that the dead and injured men were
guilty of contributory negligence, but it
would appear that the regular employees
of the plant should have made certain
that the steam was turned off before
allowing anyone to work on the piping.

New Haven Meeting of the
A. S. M. E.

The members of the American Society
of Mechanical Engineers residing in and
about New Haven have organized for
the purpose of holding local meetings, the
first of which was held at the new Mason
laboratory of Yale University on Novem-
ber 15.

It was fitting that this meeting of me-
chanical engineers should be the first
public use made of the auditorium of
this laboratory of mechanical engineer-
ing, which has just been completed un-
der the direction of Prof. L. P. Brecken-
ridge, and had been used by the classes
of his department for about a week.

The topic of the meeting was "Cost of
Power" and the following papers were
presented:

"Cost of Power with a Small Gas-
producer Plant," by Hunnewell.

"Cost of Power with a Small Hornsby-
Ackroyd Oil Engine," by Professors
Pfleghar and Lockwood.

"Small Steam Turbines," by A. W. J.
London, of the Terry Turbine Company.

"The Hartford Electric Light Company,
Its Power Plant, Distribution System and
Public Service," by Charles F. Scott, pro-
fessor of electrical engineering, Sheffield
Scientific School.

The oil-engine paper appears in this
issue, page 855, and the others will re-
ceive attention in due season.

The meeting was divided into an after-
noon and an evening session, the three
papers first named being presented and
discussed in the afternoon. The evening
session was addressed by President E. D.
Meier, who commended the undertaking
of such local meetings of the society and
told of movements in that direction in
other parts of the country.

Between the sessions the facilities of
the Yale Dining Ciub were made avail-
able to those attending the meeting, and

the laboratory was open for inspection
before and after the sessions.

E. S. Cooley, of the Connecticut Com-
pany, and chairman of the committee
having the local meetings in charge, pre-
sided at the afternoon session and Prof.
L. P. Breckenridge presided in the even-
ing^

The Mechanical Engineers

The fall meeting of the American So-
ciety of Mechanical Engineers will be
held at the Engineering Societies build-
ing, NeW' York, December 5 to 8. The
president's address will be made on Tues-
day evening, followed by a reception.
The annual business meeting will be held
Wednesday forenoon, at which time will
also be found for papers upon the fol-
lowing subjects:

"The Turret Equatorial Telescope," by
James Hartness.

"Expense Burden," by Sterling H.
Bunnell.

The Wednesday afternoon session will
be devoted to boilers with two papers:

"Tests of Large Boilers at the Detroit
Edison Company," by D. S. Jacobus.

"Strain Measurements of Some Large
Boilers under Hydrostatic Pressures," by
James E. Howard.

The papers of Messrs. Jacobus and
Howard are to be found in abstract on
pages 840 and 845 respectively.

A session will be held concurrently to
consider papers dealing with the manu-
facture and use of cement.

A reception will be given by the ladies'
committee from 4 to 6.

On Wednesday evening, Dr. Robert
Simpson Woodward, president of the
Carnegie Institute, of Washington, will
deliver a lecture on "Geo-Dynamics, or
the Alechanics of the Formation of
Worlds."

Thursday's papers of the main society
deal largely with machine-shop practice,
the one which may interest Power read-
ers being, "A Variable-sped Power
Transmission," by G. H. Barrus and C. M.
Manly.

The Gas Power Section, however, will
hold its session on Thursday forenoon
and will discuss the following papers:

"Oil Engines," H. R. Setz; "Tests of
an 85-horsepower Oil Engine," Forrest
M. Towl ; "Design Constants for Small
Gasolene Engines," William D. Ennis;
"Natural-gas Engine of 1000 Kilowatts,
Tests, Construction and Working Costs,"
E. D. Dreyfus and J. V. Hullquist, an
abstract of which will appear in an early
issue.

On Thursday afternoon the members
of the society are invited by the White
Star line to inspect the SS. "Olympic,"
the largest passenger steamer afloat. The
usual reunion will be held at the Hotel
Astor in the evening.

At the Friday morning session no
papers will be presented of special in-
terest to power-plant engineers.

December 5, 1911

POWER

863

Issued Weekly by the

Hill Publishing Company

Jobs A- Hill, Pre^. i»ii'i Tre*.-. Rob't SIcKeas, Sec'y.
503 Pearl Street, New York.

122i?oath MiPbih-sn BoolfvaH. Chir«€a

6 Bouveric Sln-el, London, E, C
Uoler tlen LinaeQ ;i— B«rUu, 3i. W. 7.

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must be given — not necessarily for pub-
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Pay no money to solicitors or agents
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Entered as second class matter, De-
cember 20, 1910, at the post office at
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of March 3, 1879.

Cable address, "Powpcb," N. Y.
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Contents

im^L

( ll;CLL.\ Tln\ tiTA TEUEy T
Of thiK issue 30.1100 copia an printcil.
h'one sent free rcyularly, no returns from

news enmimnim, nn back numbers. Figures

are livr, nrt ciiiulntlnn.

PAGE

Where Current Is Sold for 2i-i Cents. . . . .S:i8

Tfst of World's Largest Boilers 840

KITect of Air I'ressurf 842

Marine Turblne-Ent'lne Installation x-i'A

Strain Measurements of Rollers 845

COi and Boiler Kfflclency 847

Changing Alternating to Direct Current 8.52

I'recautions against Electric Shocks S."i4

.Mr. Foi'3 Alternator Trouble 8.)4

Tnatment of ('ommulalor Brushes 8.i4

Imprcved Kathbun Valve fiear >-.>■)

*'ost of Power l*roduced Ity an Oil En-
gine .s.V.

Mr. Caton's Dle»d Knginc Diagram .8.J0

ili'iillng Plant of the New York Public

Library X",

Contlnuous vs. Intermitlent Heating 8<io

A Water Heater I-roMem 8«1

A Homemade Siphon 8t51

.Measuremenl of Air Velocities 801

Fatal Piping Accident at Scranton 8i!2

I'Mltorlals 86S-864

I'rncilcfll l.ettcrs :

Keducing Valve In Steam Main....
New Way of Packing a Stuffing Box
.... I'Ipe Bender. . . . Enlarge<i Hole
In Stuffing Box liiands. . . .oil F'Ired
Furnace .... I,4^sses In T'nallned
Shafllng .... Slop Bearing I'limp
Ki-gulator. . . .Steam Cage Stuck. . . .
I'aiise of Apparent Click In a Cylin-
der. ... Polishing Itoiind Brass and
Steel. .. .I'nenmnllc Lift on Valves
....Eyebfdt for Manhead. ,. .Mirror

Smoke Detector. Sr.."-8fl7

tUscusslon l>>lters :

inertia of Air Compressor Intake
... .Transmitting •'apacltles of Pul-
leys .... Air Compressor Iliinnlng
Under. .. .Sand for Hot Bojcs...
Drj- Back Marine Boiler. . . .Iliinnlng
Corliss Knglne with one Steam Valve
. . . . Vibrnllons of lndl<-fllor Pencil
....Pressure In IMschnrge pipe,,,.
Prevent Stnndpipe Freezing . , . ,
Water Wrecked l,ow Pressure Cylin-
der. ... Value of COj Recorder...,

"Tiilferenllal" Chain Block fJraft

Personal Efflclonry «flf«-»71

Pipe Bends

It has already been mentioned from
time to time in the editorial columns that
of all parts of a pipe line the fittings
should be the strongest. The reasons for
this are many, but perhaps the most im-
portant of them is the severe strain to
which they are subjected by the expan-
sion and contraction of the piping. This
action, which always obtains in all steam
piping, is practically impossible to over-
come and in time is liable to have a
•deleterious effect upon the fittings. For
this reason it has become quite cus-
tomary to install fittings of cast steel
for high pressures and extra-heavy cast-
iron ones for the more moderate pres-
sures. There is also danger from gas-
kets blowing out, as well as the annoy-
ance and economical loss due to leaking
joints, etc. These points are now re-
ceiving more and more consideration by
engineers when laying out new installa-
tions, with the result that, wherever pos-
sible, pipe bends are resorted to quite
extensively.

This method for getting around cor-
ners, etc, is not at all new, however,
for it was not many years ago that the
multiplicity of fittings now available for
pipe lines could be obtained, and there
are many old pipefitters yet living who
can look back to the time when crooks
and turns in a pipe were made by bend-
ing it with practically no other tools
than two deft hands. Those were days
of comparatively low steam pressures
and the advent of fittings was doubtless
hailed with much satisfaction. The
greater steam and water pressures now
demanded, however, make the cast-iron
elbows more or less unsafe; consequently
the pipe bend has again returned.

In addition, there is the fact that pipe
bends are very little, if any, more costly
to install than nttings. In the first place,
gnod practice demands that a long-sweep
ell of ample weight and strength be used
and to the expense of this must be added
the cost of two gaskets — probably of cop-
per—two sets of bolts, cutting the thread

on one end of each of two pipes and,
added to all of this, the cost of the labor
required to make up the two joints. By
totalizing all of these items it will be
found that the cost will probably be equal
to, if not more than, the cost of betiding
the pipe. Furthermore, the use of pipe
bends would effect a saving in the cost
of the pipe covering as well as in main-
tenance. Some slight saving in the pipe
would also result as less is required in
making the bend than when using an ell.
In laying out a piping system with
wrought bends, it is important to use the
longest radii that conditions will allow
because, first, it will permit a more free
passage for the steam, and, second, the
bends can be more easily and cheaply
made. The minimum radius should not
be less than six times the nominal diam-
eter of the pipe for sizes from three to
six inches inclusive, and from three to
four times the diameter for the smaller
sizes. For sizes above six inches the
minimum radius should never be less
than seven times the diameter. By ad-
hering strictly to such limits there is no
danger of so stretching the material that
it will become attenuated or oxidized and
thereby lose its strength. Pipe as large
as twenty- four inches in diameter has
been successfully bent to a radius of
eighteen feet.

The Del ray Boiler Test

Never before has so remarkable a test
of so remarkable a pair of boilers been
conducted as that reported upon page
840 of the current issue.

The boilers at the common rating often
square feet of heating surface per horse-
power have a capacity of 236.'i horsepower
in a single unit, and each will in connec-
tion with the turbine-driven generator
which it supplies produce (lOOfl kilowatts
of electricity regularly and from 7000
to 8000 in the evening. The furnace is
2fi..S by 14 feet, and with the inclined
grate has a fuel surface of 405 square
feet in one case and 44(i in the other.

The tests extended over B period of

nearly three months, and for six weeks
over fifty men worked in eight-hour
shifts, day and night, exclusively upon
them, the average quantities handled
hourly being eight tons of coal, seventy-
five tons of feed water and a ton of
ashes. The evaporation was carried to
214.8 per cent, of the normal capacity
and the efficiencies exceeded eighty per
cent, in several tests and never fell below
seventy-five in the reported results.

The efficiency on the maximum forc-
ing test above referred to was 76.18,
with the flue gases leaving at 668 de-
grees. The radiation and unaccounted-
for losses are very small, averaging be-
low three per cent.

Unless unforeseen difficulties of main-
tenance and operation develop, it is likely
that the great turbine units now avail-
able will be served by boiler units of cor-
respondingly increased capacity.

Small Rope Drives

Study of the reports on rope drives
in foreign countries and observation of
the extent to which cotton rope is there
used for small drives lead to the belief
that there is a field for the use of rope
in this country as a medium of trans-
mission between main and counterdrives
and even between the counterdrives and
the machines. It does not seem unrea-
sonable to assume that by the use of
pulleys and ropes of proper size econo-
mies could be effected over the use of
belts. The rope is capable of a more
uniform drive because of the reduction of
slip, its first cost is lower and, due to
the decrease in the necessarj- width of
pulley, it requires less room for proper
operation. Further, owing to the much
higher speed of travel permissible with
rope, the total efficiency of the rope drive
may be much increased over that of the
belt drive and the wear and tear on the
shafting reduced, owing to the decreased
weight of the driving pulleys.

It seems a pity that the practice which
has proved so successful in drives of
this character is not carried further into
the smaller types of drive, using cotton
ropes in diameters of from 1 to JX inch,
and replacing the smaller sizes of belt.
In this country cotton rope has not made
a very great success, largely owing to its
first cost: but abroad the cotton rope is
quite successful for both long and short

POWER

drives and also for the smaller sizes of
drive.

It is reported from time to time that
a rope drive has been replaced, owing to
the ropes wearing out and thereby giving
trouble. This wearing out is doubtless
the result of two causes:

First, rope made of material not thor-
oughly well adapted to driving, and not
susceptible of much bending without a
material distortion and destruction of the
fibers. The fibers being hard, they in-
evitably cut one another, resulting in a
rapid destruction of the rope, particularly
if it is used over pulleys of small diam-
eter.

Second, the employment ^f sheaves or
pulleys not adapted for use with the
ropes that are run upon them. It has
been found by repeated experiment that
ropes of different materials require
grooves of different shapes, and that un-
der different conditions of drive the
grooves may have to be varied over con-
siderable ranges, using either flatter or
sharper grooves, in accordance with the
character of the drive. It is, therefore,
necessary in order to have a successful
and economical drive, first, that the rope
be of a material properly adapted to the
purpose; and, second, that the sheaves
be properly adapted both to the rope
and to the conditions of drive.

Condensing Water Doing
Double Service

At the Canton, O., electric-light station
they are planning to use the condensing
water in two temperature stagea. It
comes from driven wells at a temperature
of about fifty-one degrees. They will use
it first in the condenser for the steam
turbine and obtain a good vacuum by
keeping the temperature of the circulat-
ing water down to eighty or ninety de-
grees. It will then go to the condenser
of a piston engine, where it will readily
maintain the twenty-six-inch vacuum de-
sired.

This is one of the few stations which
can draw a plentiful supply of cold con-
densing water out of the ground under
the station and let it run away in a brook
when they have finished with it.

December 5, 1911
Safety in the Boiler Room

In Germany, no shell boiler nor water-
tube boiler having drums is allowed to
be set under occupied workrooms or
premises. Where the floors above are
occupied, water-tube boilers without
drums are used. In all boilers the fur-
nace doors and other openings must be
safe against opening by pressure within
the furnace and a passage from the in-
terior of the furnace to the outside air
must be provided for the steam in case
of the rupture of a tube. Such precau-
tions would reduce the number of fatal-
ities from tube bursts now so common
in this country. The suggestion is sub-
mitted for the prayerful consideration of
designing engineers, power-plant owners,
boiler-insurance companies and govern
ment boards of boiler control.

i

One chronic kicker in an engine or
boiler room is like a bad apple in a bar-
rel of good ones; it makes all the others
feel rotten.

The Ohio Society of Mechanical, Elec-
trical and Steam Engineers has just cele-
brated its tenth birthday. May its second
decade be as creditable and successful
as its first.

To know how the "other fellow" does
things is best learned by paying a visit
to your neighbor's plant occasionally.
You may be able to tell Mr. Neighbor a
thing or two as well.

I

That Power's "foreword" page some-
times has a financial as well as educa-
tional value is instanced in a letter re-
cently received from an engineer who
framed the foreword "Hope" (in the
September 26 issue) and hung it in the
engine room. The manager read it and
the engineer got a raise of S3 a week.

There are more factors to deal with
in estimating the safe working pressure
of a boiler than the stress on the longi-
tudinal joint and its efficiency. See other
pages of this issue.

Air. Bailey's paper on "The Fusing
Temperature of Ash" suggests the idea
that grate and clinker troubles may be
avoided by running the fuel bed as far
as possible as a gas producer and burn-
ing the gas in the combustion chamber.
In other words, keep the fire bed at as
low a temperature as is consistent with
gasifying the amount of coal required;
avoid melting the incombustibles, and de-
velop the heat mostly above the surface
of the fuel.

December 5, 1911

POWER

865

Reducing Valve in Steam
Main

Many concerns are i^utting up good
buildings, but their power-plant equip-
ments are far from being efficient; not
only is the selection of the machinery
and equipment at fault, but the general
layout and construction are not up to the
standard.

The example cited herewith is taken
from such a plant in which there is a
12x30-inch Corliss engine. On the steam
line leading to this engine is a reducing
valve which reduces the pressure from
100 pounds to a lower pressure before
entering the cylinder of the engine, the

Fig. 1. Light-load Diagram

Fig. 2. Diagram after Load Had Been
Increased

idea being that this effects a saving with
light loads on the engine.

There is very little use in buying a
Corliss engine and then putting a throt-
tling governor on it. One of the main
features of this engine is the high initial
steam pressure and a sharp cutoff and
expansion of the steam. Putting an ob-
struction in the main steam pipe to pre-
vent an engine from working economical-
ly is a piece of nonsense. By lowering
the steam pressure with the reducing
valve the engine will carry the steam fur-
ther in the stroke and cause a much later
cutoff and less expansion. Thege con-
ditions lack economy, bring the Corliss
engine nearer to a working level with
the common throttling engine, and lose
all the points of merit which the Corliss
engine possesses when properly operated.
This plant is not economical in its opera-
tion.

The accompanying diagrams. Fig. 1,
show the working of this particular en-
pine at light load and would lead one to
believe thif they came from a common
throttling engine. The diagrams shown
in Fig. 2 were taken from the same en-
gine under an increased load. The fea-
tures of the diagrams arc as bad as the
steam-pipe arrangement. One end shows
a late admission and a leaky exhaust
valve, and the opposite end might be
recognized as coming from a Corliss en-

Practical

information from the.

man on the job. A letter

^ood enough to print

here will be paid forr

Ideas, not were words

fv3nted

gine, but as a whole one could not find
a steam plant working under worse con-
ditions. The plant has every appliance
one could think of, but the steam mains
leading to the engine and pumps were
uncovered.

C. R. McGahey.
Baltimore, Md.

New Way of Packing a
Stuffing Box

Some time ago I had trouble with a
leaking stuffing box, and was unable to
prevent the leakage owing to the scored
condition of the piston rod.

I finally remedied the trouble by put-
ting one round of packing in the stuffing

Section through Stuffing Box

box in the usual way. I then cut enough
lengths of packing to go around the pis-
ton, as shown, each strip being cut to
the full length of the stuffing box.
Graphite in paste form was applied to
each piece, and the gland tightened to
press the packing, after which the gland
was loosened and another round of pack-
ing was inserted in the stuffing box.

I have used this method on air com-
pressors and duplex pumps, and also on
centrifugal pumps when the shaft has
been worn or grooved.

C. W. IBACH.

San Pedro, Cal.

Pipe Bender

The accompanying sketch shows the
details of a conduit bender I made to
bend '.>-, '4- and 1-inch conduit elbows.
The base is a cast-iron plate IJi inches
thick, 12 inches wide and 24 inches
long which can be fastened to a bench
or wall. The lever /. is about 5 feet long
and is made of ';x2-inch machine steel.
The pivot P, on which the half wheel U'
and lever are mounted, is made of cold-
rolled shafting, turned down to 1 inch,
with a collar next to the plate.

In the sketch the bender is shown
rigged up for bending K;-inch conduit.
For bending the larger sizes the half

S

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"i- 'f*

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Ijl'l "

Slot fory%
j-P.pe \

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L

Device for Bending Pipe

wheel is changed for another having a
larger diameter and the roller R is moved
out further on the lever.

For bending J-j-inch elbows I use a
half wheel having a minimum diameter
of 7'^s inches, for 'j-inch pipe a mini-
mum diameter of 9\s inches, and for
bending 1-inch pipe a wheel having a
diameter of lOi^i inches. The small
roller is used for all three sizes, but its
position on the lever is changed.

To bend the pipe, place it in the slot
between the wheel and the roller; the
lever is pulled around through a lit le
more than 90 degrees, as there is al-
ways a little spring to the pipe, and the
bend is completed. No clamping of the
pipe is necessary as the binding action
of the lever will hold the conduit in the
position in which it is placed in the slot.
With this bender uniform bends are as-
sured.

Bends made with a "hickcy" arc satis-
factory where no uniformity is required,
such as in conccnlcd work or in makin"
bends on conduit already In position
where a bender could not be applied.
But for exposed work, where neatness
and appearance count, it rcqui"cs con-
siderable skill and time to make all of
the bends uniform with a "hickcy,"

866

POWER

December 5, 1911

whereas with this bender anyone can
quickly and easily mal<e the bends with
every assurance of their being uniform.
P. Justus.
Cleveland, O.

Enlarged Hole in Stuffing
Box Glands

Friction and scoring of piston rods,
valve stays, etc., can be reduced by bor-

Enlarced Holi; in Gland

ing the stuffing-box glands as shown in
this slietch.

Georgk R. Williams.
Findlay, O.

Oil Fired Furnace

The accompanying stcetch shows the
principal dimensions of an oil-fired fur-
nace for an 18-foot by 72-inch return-
tubular boiler. The walls are built with-
out any air space and are 30 inches thick
at the base. The furnace at the grate
level is 60 inches wide, or 12 inches less
than the diameter of the boiler. The
side walls on the inside are built slop-
ing, as shown, so that they clear the shell
4 inches at a point level with the center
of the boiler, and are racked in to within
''< inch of the shell at a point level with
the center of the top row of tubes.
The space between the brickwork and the
shell is 911ed with asbestos rope.

This construction insures exceptionally
long life to the lining of the furnace. The
lining of an oil-burning furnace above
the grate is not subjected to the rough
usage necessary to remove the clinkers,
as is the case when burning coal or
lignite, but as oil-fired boilers are usually
operated at higher rates of evaporation
than when burning coal, the higher tem-
peratures incident to such crowding must
be taken care of. Although this narrow
furnace might be objectionable with some
fuels, it is verv desirable when burning
oil.

The entire lining of the furnace should
be of firebrick, rubbed in with a thin
batter of fireclay and a header with every
fourth course.

The grates are of the stationary type
usually used with coal, the front end be-
ing set 30 inches from the shell and the
rear end 8 inches lower. The grates are
partially covered with firebrick, leaving
a strip 12 inches wide at the front end
for the admission of air.

No bridgewall or spatterwall is used.
The combustion chamber is paved with
three layers of brick, laid flat, without
mortar. The rear wall is 24 inches from
the rear head. The burner is placed in
the front end between the doors, 8 inches
above the grates, .and is set so as to throw
the fire slightly downward.

Some of the advantages of this con-
struction are as follows: There is noth-
ing to cause the flame to impinge direct-
ly against the shell of the Ijoiler; there-
fore there is no danger of injury to the
sheets by the intense local heat.

supporting the posts to which the shaft-
ing was attached had settled.

I took charge of the steam plant about
this time and found the frictional indi-
cated horsepower greatly in excess of
what it should have been for this size
of mill. This was plainly attributable to
the line shafting, and an investigation
was made.

The main-line shaft, 200 feet long and
from 5I;1 to Zilz inches in diameter, was
found at one point to be down Js inch
and up -5 8 inch in 20 feet, and nearly
as bad at other hangers. It was out of
level Ks inches in its total length and
equally as much out of line.

When this was corrected a difference
of 40 horsepower less was made under
the same load conditions, in a total of
400 horsepower.

Conditions equally as bad, no doubt.

wmm:^zmmmm^i

Fuel-oil Furnace

The flame is kept away from the shell
as much as possible, and as the brick in
the bottom of the combustion chamber
become incandescent when the furnace is
in operation, a high temperature is main-
tained throughout the entire combustion
chamber, a condition that is very neces-
sary to secure economical combustion.

Having no checker work, the furnace is
easily accessible, thus permitting a
thorough inspection of the boiler without
removing any of the brickwork.

J. T. Wlliams.

Brownsville, Texas.

Losses in Unalined Shafting

Engineers and superintendents who
have never given special attention to the
matter of unalined shafting as a source
of power waste must have been sur-
prised by Mr. Kieffer's article of October
10. Many readers, previous to their
perusal of this article, had doubtless
never dreamed that conditions of waste
through shafting alone could exist to
the degree described, yet the line shafting
in many mills and factories is a fruit-
ful source of prolific waste and in many
cases unsuspected by the management.

I know of a case where a new factory
had been built and operated for four
months. It was then idle four months
and again started. In the meantime the
green timbers and posts used in the mill
construction had dried out and the piers

obtain in older factories, and if the horse-
power excess were to be figured down
to the coal pile at so many pounds per
horsepower-hour, some startling figures
would result.

F. C. Holly.
Yazoo City, Miss.

Step Bearing Pump Regulator

The illustration shown herewith is of
an automatic regulation I have been
using in a 4000-kilowatt, two-unit plant
for over three years with entire satisfac-
tion.

On the steam line of the step-bearing
pump, and above the hand throttle, is
placed the automatic throttle A, which is
fitted with a pulley B. From the weight
C, on the accumulator, a ;4-'nch wire
cable runs over suitable sheaves to the
point D. About 8 feet of flat-link chain
is fastened to the cable at D ; and is run
once around the wheel and bolted to the
pullev at F and terminates at the weight
E.

A little experimenting with the ac-
cumulator up and the pump running will
determine which link of the chaiiv the
bolt F must pass through to hold the ac-
cumulator at a point that is a safe dis-
tance below its positive stop.

The pulley stop G is fastened to a stud
of the valve bonnet or other suitable
place; and so placed, in reference to the
position of the stop bolt H. that the two
will come in contact when the throttle is

December 5, 1911

POWER

867

almost one turn open, and again when it
is shut. The throttle should be of suffi-
cient size to enable the pump to hold the
accumulator up at the lowest working
steam pressure, when operating within
the limits of the pulley stop.

Cause of Apparent Click in
a Cylinder

In the plant where I am employed
there was recently installed an automatic
engine stop. The automatic stop valve,

Regulator for Step-bearing Pump

The pump is started up and shut down
by the hand throttle. The regulating
valve requires no attention after being
once properly set.

W. E. Bertrand.

Philadelphia, Penn.

Steam Gage Stuck

The plant in which I was head fire-
man on the night shift had five water-
tube boilers, all connected to one header.

On Saturday evenings the day man
would cut out one boiler for washing on
Sunday. It was my place, Sunday night,
to head up the boiler and get it fired up
and cut in with the rest.

This Sunday night I went at the job
as usual, built a fire under the dead
boiler after putting in two gages of water.
I had about 75 pounds pressure on the
other boilers and after a reasonable time
the gage of the boiler I was firing up
showed the same pressure. I was about
to go up over the boiler and cut it 'n with
the others when both safety valves blew,
although they were supposed to blow
at 125 pounds pressure. I pulled my fire
out at once and put on another steam
gage, which indicated HO pounds pres-
sure. The old gaee had been all right
on Saturday evening, but for some rea-
son It would not show over 75 pounds
pressure on Sunday. Shortly after this
the inspector Inspected the plant and cut
the pressure down to 110 pounds per
square inch. Had the safety valves not
blown, the boiler would doubtless have
exploded.

One cannot be too careful about a
steam plant.

HARoin J. Wilkinson.

Angola, Ind.

which is situated above the throttle valve,
has a 1-inch drip pipe leading from it to
a 3-inch pipe which takes the discharge
from an ejector and a steam trap to the
sewer.

After installing the engine stop I got
an occasional click which seemed to
come from the cylinder. It would ap-
pear two or three times in succession
and then disappear for an hour or so
and then come again a few times. I con-
cluded that since there was no noise in
the cylinder before installing the auto-
matic stop that it must in some way be
caused by it.

For a trial I disconnected the automatic
stop-valve drip from the ejector-dis-
charge pipe, plugged the discharge pipe
and left the drip open to the atmosphere.
I had no further click in the engine, and
presume that the noise was caused by
water hammer in the automatic valve
drip pipe whenever the ejector or the
trap operated.

Frederick M. Perras.

Mansfield, Mass.

Polishing Kouiul 13ra.s.s and
Steel

It is often neccssar>- to resort to emery
cloth in order to clean badly corroded
nr tarnished brass, steel rail posts, rods,
etc., and this becomes real labor when
there is much to be done. However,
this work may be rapidly and easily
accomplished hy wrapping the emery
cloth or paper tightly around the rod to
be polished. Then take a couple of turns
of heavy waxed cord or, better still,
some broad tape arniind the emery cloth.
Grasp the two loose ends and by al-
ternately pulling them the emery cloth

may be made to revolve rapidly about
the rod and the polishing is accomplished
in a short time. Do not use too coarse
emery as this will leave scratches and
make a rough job.

In this connection, a strong solution
of potash is very useful in removing
grease and dirt from polished-steel nuts,
etc., and will make the work of polish-
ing much easier.

W. Howard Miller.

Fort Wayne, Ind.

Pneumatic Lift on \ alves

Most modern power plants are pro-
vided with air compressors and many of
the larger valves might be operated by
means of air.

Connection of Valve to Cylinder

The sketch shows my idea of this
means of application of air. The appli-
ance consists of a cylinder A, bolted to
the upper fiange on the valve body; a
piston B, fitted to the upper end of the
valve stem C, which is packed, as shown
and a four-way cock E connected by
means of unions to the cylinder A. The
illustration shows the position of the pis-
ton when taking air underneath and ex-
hausting above the piston li.

E^XDARD SOBOLEWSKI.

Cincinnati. O.

Eyebolt for Manhead

Here is a plan I have been intending
to try for overcoming the danger of
burns when letting down a manhead, also
for making the task of lifting easier:
Drill and tap a 'sS-inch hole in the head
and screw in an eyebolt.

J. C. Lee.

Jamestown, O.

Mirror Smoke Detector
I ran across a simple arrangement th^
other day which consisted of a small
mirror propped up at such an angle, and
at the proper distance from the engine
room, that it enables the engineer to see
the top of the smokestack from the door
or window of his engine room.

This device enabled him to see. without
leaving the room, whether the stack was
smoking.

W M. Bartlett.
Muskegon, Mich.

868

POWER

December 5, 1911

Inertia of Air Compressor
Intake

I was much interested in Snowden B.
Redfield's instructive article under the
above caption in a recent issue. I
do not think that there can be the slight-
est doubt but that the increase in pres-
sure at the end of the intake stroke is
due to the inertia of the moving air col-
umn.

It is reasonable to suppose that, with
suitable valve timings, the air in the in-
take connections will crowd into the cyl-
inder as the piston speed slows down to-
ward the out center. Anyhow, most
gas-engine designers have taken this ac-
tion for granted both on the inlet and ex-
haust strokes. The effects are distinctly
noticed on most light-spring diagrams,
providing that the valve timings are such
as to allow the conditions to be favor-
able.

On the inlet stroke an increase of
pressure is discernible before the out
center is reached. Air and gas are sub-
stances which are easily compressed,
and, since they have weight, they must
also possess inertia if once set in mo-
tion. The piston sets the column of gas
or air in motion, doing work upon it
until the piston has attained its maximum
speed. The piston is then decelerated
through the medium of the connecting
rod and crank, giving up its inertia in
the process, but the compressible gas,
having no such rigid retarding agents,
presses on by virtue of its inertia and re-
delivers the work which has been ex-
pended upon it by the piston in compres-
sing itself. This is the only logical con-
clusion which can be drawn, since if a
body has work performed upon it so as
to produce motion, that work must be ex-
pended somehow before the body comes
to rest.

Then, on the exhaust line of a light-
spring diagram a drop in pressure is
often noticed close to the in center. The
column of gases passing down the ex-
haust pipe causes an inductive action
to be set up in that pipe, so much so
that many builders of gas engines have
their exhaust and air valves open to-
gether through quite a few degrees of
rotation so that scavenging can be ef-
fected by the pure air rushing through
the combustion space toward the open
exhaust pipe.

Now air could not be induced with the
piston still rising or just at the in center
unless it were either at a pressure above

atmospheric, which is never the case so
far as I am aware, or unless work were
done on it by a difference in pressure
in favor of the atmosphere. To effect the
latter proviso the only practicable agent
is the column of gases moving away
down the exhaust pipe, and since the pis-
ton has suffered negative acceleration
from its maximum velocity. It can only
be the inertia of the column from which
ihe work can be obtained.

1 believe that this action was the sub-
ject of a patented scavenging device con-
sisting of a long straight exhaust pipe

Fic. I. Indicator Diagram from Com-
pressor, Showing Effect of Air
Inertia

of a diameter and length which vary
with the size of the engine. At the same
time it must be remembered that correct
proportioning has much to do with the
effectiveness of such a device. An ex-
actly opposite effect to that desired may
be obtained by a pipe too small in cross-
section or of too great a length for the
piston displacement of the engine to
which it is applied. The internal resist-
ance then set up greatly detracts from
the power available by piling up the pres-
sure in the cylinder at the end of the
exhaust stroke instead of decreasing it,
thus limiting the amount of fresh mix-
ture which can be admitted to do effective
work.

Whether Mr. Redfield's figures and cal-
culations are, or are not, reliable in deal-
ing with a matter of this description, is
open to discussion. I think myself that
they would vary in each individual case
and that to obtain the best results one
must have recourse to experimenting
with valve settings in conjunction with a
reliable indicator.

That the loops B in Fig. 1 of his arti-

cle are not caused by the inertia of the
moving parts of the indicator motion is
proved by the fact that they are equally
marked on diagrams obtained from
optical indicators.

John S. Leese.
Manchester, Eng.

Transmitting Capacities of
Pulleys

As the results described in a paper by
Professor Sawdon on "The Transmitting
Capacity of Pulleys," read before the
National Association of Cotton Manufac-
turers and abstracted in the October 17
issue of Power, do not fully accord
with those obtained in similar tests made
at the Worcester Polytechnic Institute,
at the Lowell Textile School and with
other pulleys in use under factory condi-
tions, careful consideration and discus-
sion seem desirable.

The paper presented was prepared at
the request of the Rockwood Manufac-
turing Company and, it is stated, was
originally undertaken with a view to ob-
taining certain observations on cast-iron
pulleys operating at different belt speeds
and tensions. Later the test was extended
in scope to embrace plain wood and
paper pulleys, and still later to include
cast-iron, wood and paper pulleys
equipped with cork inserts.

Table 1, in Professor Sawdon's paper,
referring to the relative capacities
of several types of pulleys, is based
on results obtained from actual tests, the
other table being based on a computa-
tion of questionable merit.

Although it is stated that the two tests
referred to were made with the corks
projecting ^W and ^j inch respectively.
Table 1, showing the relative coefficient
of friction of the several types of pulleys,
does not indicate this but shows corks
with five different degrees of projection
ranging from rih to rf Jtr inch, no tests
of the several types of pulleys apparent-
ly being made under like conditions.

Although it is stated that six different
initial belt tensions were used, running
from 37.5 to 225 pounds per square inch
of cross-section, it is interesting to note
that the cur\'es have been plotted on a
basis of about 170 pounds to the square
inch instead of at lower belt tensions,
and this in the face of the statement
made elsewhere in the paper that it is
an accepted fact that the higher the work-
ing stress in the belt, the shorter its life.
That this tension of 170 pounds is un-
necessan," is shown by results obtained
in daily use and in tests recently com-

December 5, 1911

POWER

plated at the Lowell Textile School,
which were made at a belt tension of 75
pounds to the square inch of cross-sec-
tion.

Again, it is to be noted that, although
the paper pulley is primarily a gen-
erator, motor, or other pulley operating
at high speed, small arc of contact and
usually under adverse conditions, this
test is made with a 5-inch single belt
on pulleys 24 inches in diameter by 8
inches face running at but 348 revolu-
tions per minute and with a full 180 de-
grees arc of contact — a quite different
set of conditions from those under which
motors usually run in mills and fac-
tories.

In studying Table 1, which is presented
in order that a simple and direct com-
parison may be made, the above di-
mensions should be borne in mind to-
gether with the fact that no maximum
figures are given and that no results are
shown at over 2 per cent, slip, although
it is elsewhere stated that many kinds
of service demand at times overload capa-
cities as much as 50 per cent, of the
normal load and that both wood and cast-
iron pulleys equipped with cork inserts
show a large overload capacity at high
slips.

Why, in the absence of actual data,
the report should be further amplified by
a computation the results of which are
shown in Table 2, not based on actual
tests, but worked up on an old standard
formula on the basis of the altogether
undesirable belt tension of 250 pounds
to the square inch, I cannot comprehend.

Referring again to Table 1 we find
some remarkable results; for example,
contrary to any data previously seen by
us, we find that the plain paper pulley
has 152.8 per cent, greater transmitting
capacity than a plain cast-iron pulley,
and that a paper cork-insert pulley while
transmitting less power than the all-
paper pulley still shows 118 per cent,
greater transmitting capacity than a plain
cast-iron pulley, which figure far ex-
ceeds our claims.

Lawrence Whitcomb,

Treasurer,
The Cork Insert Company.

Boston, Mass.

Air Compre.s,sor Running
Under

In the October 31 number, John S.
Leese shows four illustrations represent-
ing air compressors and asks to be cor-
rected if wrong. I would say that he is
correct in Figs. 1, 3 and 4; in Fig. 2 he
is wrong. The steam end of Fig. 2 is
correct, but the air compressor is run-
ning over, and as it gets its power from
the crank shaft, the pressure on the
guides would be upward.

This subject is more complicated than
it might appear to be at first glance.
Take, for instance, a cross-compound

machine with the cranks set at right
angles. Each steam piston during the
first part of its stroke does some work
on the crank shaft and some work on
the opposing air piston. At half stroke,
or a little later, the effective pressure on
the air piston will be equal to that on
the steam piston; it continues to increase
until near the end of the stroke while the
pressure in the steam cylinder is falling
and it takes work from the other side
of the machine, transmitted through the
crank shaft and connecting rod to carry
the pistons to the end of the stroke. In
this case, with the machine running over,
the pressure on the guides will be down-
ward during the first part of the stroke
and upward during the latter.

James H. Campbell.
Bloomington, 111.

After such an experience, I would pre-
fer not to use sand as a hot-box cure.
P. C. Forgard.
Lake Preston, S. D.

Referring to Fig. 2 of Mr. Leese's
letter in the October 31 issue, it will be
seen that the connecting rod of the air
compressor and that of the steam engine
both connect to the same crank pin.

Mr. Leese states that all the machines
in the various sketches are supposed to
be running under, but with a machine
of a design as shown in Fig. 2, when the
steam engine is running under, the air
compressor would be running over. Con-
sequently, the thrust would come on the
top guide of the air compressor instead
of on the bottom guide, as shown.

Louis Allen.

Union, N. Y.

Sand for Hot Boxes

I know of one engineer, for whom I
have the highest respect as to his me-
chanical ability, and he uses a certain
grade of sand for hot bearings.

In connection with his plant he has a
machine shop in which is a large grind-
stone. Whenever this stone required
truing up, the engineer would save about
a quart of the powdered stone resulting
from this operation, and he considered
it better than almost anything else he
could use for smoothing up a rough bear-
ing.

When he had a new shaft or an ob-
stinate box he would use a small quan-
tity of this stone with a liberal amount
of oil. By turning the shaft slowly the
surfaces of the bearing were cleaned
without any scratches. The application
of a stream of water from a hose would
soon clean out the sludge.

G. S. Spracue.

Geneva, Neb.

Regarding the controversy on the use
of sand to overcome hot boxes, I should
like to add my mite of experience.

Once some kind friend put some sand
in the outboard of the engine of which
I had charge. A few minutes after the
trick was played I discovered that the
box was smoking hot and all of the
babbitt had run out of the lower half.

I have been ver>- much interested in
the discussion regarding the use of sand
for hot boxes. I have had considerable
experience with hot boxes and I have
found that in nine cases out of ten the
trouble is caused by grit getting in the
bearing. Grit always reminds one of
sand, and if I intended to destray a box
as well as damage the shaft, I would not
look for anything to no a more complete
job than grit (sand). Of course, 1 am
open to conviction, but I would rather
let someone else ust '.he sand.

H. F. BUCKLEN.

Kingwood. W. V8.

Dry Back M.^rine Boiler

Referring to Mr. Fenwick's letter in
the October 31 issue, I 'lave charge of a
Scotch marine internally fired 135-horse-
power boiler. I use 5 pounds of soda
ash per week in this boiler, and it has
been run for three months in the summer
without shutting down.

•The length of time the boiler can be
run continuously depends on the amount
of coal burned or, rather, the amount of
ashes which settles in the combustion
chamber.

I am burning about 2^^ tons of coal
per day in winter, one-half soft coal and
one-half buckwheat. This requires clean-
ing the combustion chamber about every
six weeks. In the summer, burning I J 1
tons per day, it will go three months
without cleaning.

I see no reason why this type of boiler
could not be run three months at a
time, even if a compound were used, as
the sediment will settle to the bottom
where the fire does not come in contact
with the shell upon which it settles. Then
it can be blown off once or twice a day
to keep the boiler reasonably clean.

In my experience with the internally
fired boiler I have had no trouble due
to poor circulation.

As to the size in which boilers with
corrugated furnaces can be built, to my
knowledge boilers of 300 horsepower arc
common.

Leon N. Webster.

Springfield. Mass.

In answer to Charles Fenwick's ques-
tions in the October 31 number regarding
internally fired boilers, I will tell of our
experience.

Ten years ago we were wnrni'lng along
with bad water and two return-tubular
boilers. We washed one boiler every
two weeks, but in spile of our best ef-
forts, the sheets over the fires were fre-
quently burned. We abandoned the re-
turn-tubular boilers and installed in their
place one 200- horsepower internally fired
boiler, having corrugated furnaces, and
built for a pressure of 160 pounds.

870

POWER

December 5, 191 1

This boiler has been in continuous ser-
vice for seven years, and has never been
washed oftener than once a month, and
it has run as long as four months without
washing.

'We find no trouble from poor circula-
tion, or in carrying 25 to 30 per cent.
overload.

We have been so well pleased with
this boiler that we are at the present
time operating another boiler just like
it of the same horsepower. For bad
■water, rough usage and long runs with-
out cleaning, this type of boiler has no
equal.

W. S. Harkness.

Jellico, Tenn.

Running Corliss Engine with
One Steam Valve

Answering Mr. Read's inquiry, page
523, of October 3 issue, regarding the
behavior of a Corliss engine with the
head-end steam valve removed or fast-
ened open, and the head-end exhaust
valve disconnected and fastened closed,
I say that the engine should operate sat-
isfactorily up to about half load.

There would be no great waste of

After the cutoff on the crank end oc-
curs, the steam remaining in the head
end would have to be forced back into
the steam pipe, thus raising the pres-
sure a little more.

These changes in pressure might be
so slight that they would not show up
on the diagram, depending on the size
of the ports and size and length of the
steam pipe, but a small negative loop
could be expected.

C. A. Call.

Schenectady, N. Y.

Vibrations of Indicator Pencil

I read with care the article by J. W.
Taylor, relative to the jagged expansion
lines of certain indicator diagrams, pub-
lished in the issue of October 31.

As Mr. Taylor has written, there is no
information at hand relative to these dia-
grams but to my mind sufficient is shown
on the face of them to refute the state-
ment that "they are excellent and the
engine is without doubt economical."

I think that my letter in another part
of the October 31 issue plainly points
out the cause of the wavy lines.

I do not believe that this action can

Diagrams Obtained with One Steam Valve Removed

steam as there was in Mr. Read's ex-
periment with the exhaust valve in op-
eration, and the steam consumption at
half normal load would be but little more
than if all the valves were operating
normally.

As there would be but one working
stroke per revolution instead of two, a
variation in speed showing a rise and fall
each revolution might be noticeable if
the flywheel were very light.

From the diagrams in Mr. Read's let-
ter I should judge that the engine was
carrying over three-fourths normal load.
With the exhaust valve closed it is
doubtful whether the engine would carry
this load without trouble. At half nor-
mal load the diagram for the crank end
would be almost identical with an ordi-
nary full-load diagram. For the head
end the admission line would extend the
full length of the stroke. With the ad-
mission of steam to the crank end the
pressure might drop slightly, but it would
quickly return and as the piston speed
increased would rise a little above the
admission line, due to the back pres-
sure of the steam being pumped through
the port opening into the steam chest.

be accounted for by ascribing it to steam
action, as I hold the opinion that there
is no recoil in steam when it is expand-
ing to a gradually augmented volume,
as in springs when they are suddenly
released from confinement, and after
some years' experience in handling it, I
have concluded that its action in an en-
gine cylinder is perfectly smooth.

In connection with this subject and
bearing on the reliability of the indicator
as an engineer's instrument, the follow-
ing may be of interest:

Some years ago, I had occasion to in-
dicate an engine which showed this
peculiarity and was much surprised to
note the result. All kinds of expedients
were suggested and tried and as a last
resort I decided to solder a triangular-
shaped piece of sheet metal to the upper
edge of the pencil arm in such a man-
ner that its depth was increased to 1 '4
inches, making it practically rigid, but
the wavy lines could not be disposed of.

This experiment proved conclusively
that my indicator was not at fault, but at
that time it did not solve the myster>'.

It is my opinion that the indicator,
when carefully used and its stories read

without any attempt to justify the faults
of the engines to which it is applied, is
the only true guide to correct steam-en-
gineering practice and in my dealings
with it, extending over 20 years, I have
yet to catch it in a falsehood or doing
mysterious things.

Charles F. Prescott.
Philadelphia, Penn.

Pressure in Discharge Pipe

In the October 24 issue, Mr. Murphy
presents a pump problem. According to
the data given the displacement of the
pump is about:
10' X 0.7854 X 14 X 2 X 100 X 2 =

439,824 cubic inches per minute
This divided by 231 gives 1904 gallons
per minute. Allowing 25 per cent, for
slippage, 1428 gallons per minute would
be delivered to the discharge pipe.

Assuming that a pressure of 3 pounds
is required to lift the check valve and
overcome the friction in the 6-inch pipe,
the total head in feet in the 6-inch pipe
is

80 -f 3 = 83 ^ 0.434 = 191 + feet
On page 523 of the April 4 issue there
appears a chart in connection with an
article on "The Flow of Water in Clear
Iron Pipes," by A. E. Guy. In applyingthis
chart to the problem in hand it is found
that with a 3-inch pipe at 190 feet head,
which is the head required to force water
into the upper tank, only 240 gallons per
minute will be delivered. The balance.
1188 gallons, would be pumped into the
upper tank. This, however, would be
much less, due to the increased friction
in the 6-inch pipe.

J. C. Hawkins.

Hyattsville, Md.

Prevent Standpipe Freezing

Referring to the query of Thomas
Nicholson in Power of September 12, re-
garding standpipes freezing, I would say
that I have a 16-inch standpipe connect-
ing a 150,000-gallon iron tank with a
water main. From the surface to the
bottom of the tank it is 90 feet, and the
tank is in a very exposed place.

The 16-inch pipe is covered with tarred
felt, which is wired to hold it in position.
A number of 2x4-inch split wooden rings
are fitted around the covered pipe, and
are placed any convenient distance apart.
To these rings are nailed rough but
closely jointed boards, of sufficient
widths to complete the circle, leaving a
4-inch space between the covered pipe
and the boards. This is covered with
tarred felt, wooden rings and close-fitting
boards. It should be so covered that
there will be three sets of rings, putting
over each set of boards a covering of
tarred felt; the last or outer covering
may be of 2- or 2''2-inch beaded boards.
At the top, where the standpipe joins
the tank, a close-fitting molding or strip
should be neatlv fastened. This cover-

December 5. 1911

POWER

871

ing. it is said, will withstand the coldest position to give the highest percentage

weather. of CO..

Frank C. B. Speace. Paul C. Bancel.

Cape May City. N. J. New York City.

Water \\ recked Lou Pres-
sure C3"linder

I have read H. R. Low's letter in the
October 31 number about water wrecking
the low-pressure cylinder of a cross-
compound engine. I had an experience
with water in the low-pressure cylinder
of a cross-compound engine of the Buck-
eye automatic, piston-valve type. The
engine is 20 and 36 by 33 inches in size
and runs at 140 revolutions per minute.
When it was about time to stop and there
was hardly any load on the engine, water
would get into the cylinder and things
would start.

I tried several ways of preventing this,
even to shutting off the water from the
condenser before closing the throttle, but
I still .would get an occasional dose of
water which always opened the relief
valves. Finally, 1 examined the drip
pipe on the receiver. This pipe was
about 30 feet long and was open to the
atmosphere. It had a globe valve and a
check valve in it. I removed the pipe
and found the receiver ver>' nearly full
of water. On examination it proved to
be plugged with packing which had come
from the high-pressure piston rod. The
rod being badly pitted, it pulled the
packing into the cylinder a little at a
time and finally enough was blown into
the drip to entirely close the pipe.

Since placing a new pipe on the re-
ceiver I have had no trouble due to
water.

John Jones.

Beacon Falls. Conn.

Value of CO.. Recorder

R. S. Wilhelm states in the October
24 issue that "As the percentage of CO;
is to a great extent influenced by the
draft, it demands that a draft recorder
be installed with the CO: recorder. A
combination apparatus if properly cared
for will show on the chart the percentage
of perfect combustion, and will show the
draft employed at the time the CO. was
recorded; a study of the chart will show
just in what position to set the damper
to obtain a draft through the bed of fuel
that will give the great percentage of
CO,."

The draft through the fuel bed de-
pends on the amount of air passing and
the resistance of the fire. Were this
resistance constant, then the amount of
air and the percentage of CO. would al-
ways be dependent on draft, and draft
only. But the depth of fuel and depth
of ash, accumulation of clinkers, etc..
cause wide variation in the resistance to
flow of air and no iron-bound rule can
be set down as to draft or the damper

"Differential" Chain Block

.\s regards Mr. Phillips' "differential"
chain-block problem in the October 31
Pow er, perhaps it can be more easily ex-
plained by reference to the accompany-
ing figure.

When 30 feet of chain are pulled at
the side D, but 28 feet pass up at the
side E, the other 2 feet being disposed
in the loose end of the chain, making

the end at F

(;) 1 foot

nearer the floor.

A simple rule for determining the
velocity ratio would be: Take the dif-
ference between the number of link
pockets, in wheels A and B, and divide
by 2. The result will be the lower term

The "Differential" Chain Block

of the ratio. The higher term will be
the number of pockets in the wheel off
which you are pulling.

For example, wheel A has 15 pockets
and wheel B has 14 pockets;
'.S '4

— = O..S

2

giving 9 velocity ratio when pulling at D
or H of 15 to 0.5 or 30 to I ; and when
pulling at e or C of 14 to 0.5. or 28 to I.

POBTER STAFFORn.

Eric, Pcnn.

Graft

Referring to the editorial under this
caption in the issue of October 31. it
seems to me that condemnation for this

damnable practice ought not to be di-
rected at the engineer who in a moment
of weakness accepts the bribe which is
pressed into his perhaps unwilling hands.
The party who offers the bribe is the
one who should be condemned and in
some way made to see the error of his
way. 1 think it is generally conceived
that engineers and master mechanics are
not paid on a par with men in other
trades where the back is used more than
the head.

When 1 first came to New York City,
now nearly 12 years ago, I was told that
unless I practised "graft" I could not
do business in this section. The fact
that I am "still at the old stand" is ample
refutation of such a statement. As a
matter of fact, I can truthfully say that
during the 15 years I have beea in busi-
ness for myself, I have been importuned
for graft but a very few times.

There are honest engineers and me-
chanics. Lots of them. It seems too bad
that the whole profession should be, as
it were, under a cloud because of a few
unworthy members who stoop to such
practices. So long as the world remains,
graft will exist. It does seem, however,
as though every honest man should,
whenever an opportunity affords, strike
at it and do his part toward its extermina-
tion.

Charles F. Chase.

New York City.

Personal Efficiency

I have noticed several discussions, in
recent numbers of Power, on effi-
ciency, economy, equipment, etc. When
efficiency or economy in the power plant
is mentioned we are prone to think at
once of the plant itself, of damper regu-
lators, draft gages, CO: recorders, patent
furnaces, recording gages, wattmeters,
coal weighers and other automatic de-
vices. The mechanical papers are al-
ways advertising some new apparatus or
combination which will produce greater
efficiency.

The compound man says that more
fuel is wasted because of scale in the
boilers than for any other reason: the
combustion engineer, that poorly de-
signed furnaces and improper firing arc
the most prevalent evils; the engine
builder, that the most important part
of the plant is an economical engine.

One may have the most uptodatc plant
which money, evperiencc and careful
planning can buy and yet fail to secure
efficiency.

In the last analysis it must be admitted
that the man who operates the plant is
the most important factor, as, ecncrally
speaking, on him rests the responsibility
for efficient operation. Therefore, the
first and mo"! important thing is to se-
cure a capable, efficient engineer who
"means business."

R. L. Ravbi'rn.

Kansas City, Mo.

872

POWER

December 5, 1911

Negative Loop in Indicator
Diagram

What causes the loop in the high-pres-
sure diagram after the exhaust .valve
opens to the receiver?

E. W. S.

The steam is cut off so early in the
stroke that expansion is carried below
the line of pressure against which the
engine is exhausting and at the moment
when the exhaust valve opens there is a
rush of steam, previously exhausted, into
the cylinder, raising the pressure in the

Negative Loop in Diagram

cylinder to that in the receiver. The
remedy in the case of a compound en-
gine is to lengthen the cutoff on the low-
pressure cylinder until the receiver pres-
sure is equal to or lower than the ter-
minal in the high-pressure cylinder.

Full Compression Stops the Engine

Why does a gasolene engine, which
runs all. right with the compression-re-
lief cock open, refuse to run with the
cock closed?

J. M. J.

Any one of several causes could pro-
duce this result, namely: Very lean or
very rich mixture; premature ignition;
retarded ignition; deranged valve mech-
anism; too high compression.

Oscillation of Chimneys

Do not brick and cement chimneys
oscillate in high winds? How much out
of center would the top of a well con-
structed chimney, 125 feet high, lean in
a 60-miIes-an-hour wind?

H. S. T.

All chimneys oscillate in a wind. It is
practically impossible to state what the
oscillation would be in the case presented.

The factors which influence the oscil-
lation of a brick chimney are its diam-
eter, the taper of its sides, the material
and workmanship and the rate at which
the wind is blowing.

Assuming a chimney of 125 feet in
hight and 60 inches in diameter, with a
2 per cent, taper and built with fairly

Questions arc^

not answered unless

accompanied by the^

name and address of the

inquirer. This page Js

for you when stuck-

use it

good care and material, the oscillation in
a 60-miles-an-hour wind should be about
2 inches either side of the true center
line.

Effect of Poller Factor on the
Driving Engine

Does an engine driving an alternator
have to develop any more power when
the alternating-current power factor is
low than when it is high, the true power
being the same in both cases?

C. F. R.

A very little more, on account of the
increased electrical losses in the circuits
when the power factor is low. With a
lower power factor, more current is re-
quired for the same real power; the extra
current increases the losses in all circuit
conductors and thereby increases the
total power required at the alternator
shaft.

Temperature Difference Be-
tween Steam and Water
What is the difference between the
temperature of the steam in a boiler and
that of the water from which the steam
is made?

D. M. S.

There is no difference. The tempera-
ture at which water will boil or change
into steam depends upon the pressure to
which it is subjected. Under an absolute
pressure of 9100 of a pound, that is, a
vacuum of 29.84 inches, it would boil at
32 degrees. Under a vacuum of about
2G inches it would boil at 125 degrees.
At atmospheric pressure or a pressure
corresponding to 29.92 inches of mercury
it boils at 212 degrees. At 50 pounds
absolute, 35 pounds gage, 281 degrees;
100 pounds absolute, 328 degrees; 150
pounds absolute, 358 degrees, etc.

The exact values may be found in the
steam tables in any engineer's reference
book. There are two books devoted en-
tirely to tables of the physical properties
of steam, one by Professors Marks and
Davis and the other by Professor Pea-
body.

Formula for Centrifugal Force
In the formula for centrifugal force,

F =

1.2275 \\ R

how are the figures 1.2275 found? la
the formula

F =1 2R 3.1416 TV
time is omitted and it is not clearly un-
derstood how 3.1416 is changed when
time is included.

P. J. B.

irt.2

Centrifugal force = F =

gR

where

W = Weight in pounds;
V = Linear velocity in feet per sec-
ond;
g = 32.16;
R — Radius in feet.
But

V = 2v R N
where

A' = Revolutions per second.
Hence,

P_ n X (2 TrR\)^
32.16 R
P_H X 4 X g.g R-.W^
32-16 X R
= 1.2275 \i'RX-
Where / = time in seconds for one revo-
lution, - would be the revolutions in
one second or equal to iV.

Substituting in the above equation
p_i----75 iJR

Collapsing Pressure of Corru-
gated Flue

How is the collapsing pressure of a
corrugated furnace fiue found?

C. P. C.

The pressure per square inch at which
a corrugated flue will collapse is found
by multiplying the thickness of the flue
in thirty-seconds of an inch by itself and
by 1200 and dividing this product by the
greater external diameter in inches multi-
plied by the square root of the length of
the flue in inches. The formula is
t- X 1200

DxyH

in which

< = Thickness in thirty-seconds of
an inch;
Z) = Mean diameter in inches;
L = Length in inches.

December 5, 1911

POWER

873

New Hamilton Corliss Gravity noiselessly and positively at speeds of

Valve Geir ^^°^ '^ '° '^^ revolutions per minute.

The latch and cam levers are made of

A detail view of the new Hamilton steel forgings. It is manufactured by

Corliss valve gear is shown herewith, the Hooven, Owens, Rentschler Com-

The main features are confined to the pany, Hamilton, O.

Details of New Hamilton Corliss Gravity Valve Gear

latch-block arrangement and the knock-
off lever. TTie outer end of the valve
stem has a steam crank to which is fitted
a steel crank plate. The top of the
steam-rod arm is fitted with a latch rod,
on the outer end of which is secured a
latch arm. On the inner end is secured
the knockoff lever, which carries a roller
at its outer end, as shown. This roller
rides on the foe collar which is actuated
by the governor. A governor toe plate
is mounted on this collar, and operates
the knockoff lever. There is also a safety
cam to prevent the knockoff lever from
dropping enough to permit the latch plates
to engage and open the valve in case of
governor trouble or excessive speed.
There is also a travel scale which Indi-
cates the amount of valve opening.

The illustration shows the valve gear
in a position to open the valve. The
steam rocker will be moved toward the
right, which will move the latch arm
toward the left, and when the latch
blocks engage, the valve is opened until
the roller on the end of the knockoff
lever is lifted by the governor foe plate,
which action lifts the latch plate. As
soon as the crank plate is disengaged
the valve is closed by the dashpot.

When the steam rocker moves toward
the left, the latch-plafe lever drops by
gravity to its original engaging position.

This valve gear is designed to operate

Lea Pressure Recorder

The Yarnall-Waring Company, 1109
Locust street, Philadelphia, Penn., has
recently added to its line of Lea record-
ers a pressure type, suitable for measur-
ing hot or cold water under a vacuum or
pressure, as the case may be. The gen-
eral appearance of this new type is
shown in the accompanying illustration,
which is an exterior view of the meter
with the recording instrument mounted
in a separate case on the top cover.

The notch tank is made of cast iron,
and is entirely inclosed and designed to
withstand any pressure up to 10 pounds
per square inch, or a vacuum. This en-
ables the recorder to be placed between
the open feed-water heater and the feed
pump.

A balanced float valve is shown on the
inlet on the left-hand end of the tank.
This valve is operated by a float and lever
mechanism placed below the weir on the
dischafge side, so that the weir or the
recorder will not be flooded. A water
gage is also provided on the right-hand
end of the tank for checking the opera-
tion of the float mechanism.

On the sides of the tank two glass
peepholes are provided for adjusting the
recorder to zero while the notch tank is
under pressure. This new type of pres-
sure recorder is made in sizes to cart for
200 to 10,000 boiler horsepower. Other
forms of the Lea recorder have been
given previous attention in Power.

Lea Pressure Recorofr

374

POWER

December 5, 191 1

Transportation to Seattle
Convention

On November 22 a meeting of the
transportation committee of tke National
Electric Light Association was held at its
headquarters i-n New York City.

Chairman C. H. Hodskinson announced
that the Transcontinental Passenger As-
sociation had authorized reduced round-
trip fares to the Seattle meeting as fol-
lows: From Chicago, $65; St. Louis,
862.50; Missouri Gateways (Omaha to
Kansas City, inclusive), S55; St. Paul,
$55. Dates of sale for tickets under re-
duced fares are May 27 and 28 and June
3 to 6, inclusive; final-return limit, July
27, 1912.

PERSONAL

R. Sanford Riley, of Providence, R. L,
Who as president of the American Ship
Windlass Company developed the Taylor
Stoker, has sold out his interest ifl that
company and organized the Sanford
Riley Stoker Company to exploit a new
self-cleaning underfeed stoker.

SOCIETY NOTES

The tenth annual entertainment and re-
ception of the 10 combined associations
of the National Association of Stationary
Engineers will be held on December 30,
at 8:15 p.m., at Terrace Garden, Fifty-
eighth street. Any information on tickets,
bo.xes and the regular calendar may be
had by addressing S. 1. Schoff, chairman
of the finance committee, 225 St Ann's
avenue, New York City.

The annual meeting of the American
Society of Heating and Ventilating En-
gineers will occur at the Engineering So-
cieties building, 29 West Thirty-ninth
street. New York City, on January 23,
24 and 25, 1912.

On November 8 and 9 the executive
committee of the National District Heat-
ing Association met in Detroit, Mich.,
and unanimously decided to hold the
fourth annual convention in that city, fix-
ing the dates, June 25, 28 and 27, 1912.
Papers upon the following subjects will
be presented at this convention: "De-
preciation in Underground Distribution
System," "Operation of Turbines and
Reciprocating Engines in Connection with
Steam Heating Work," "Description of a
Combined Steam Heating, Ice Making
and Electric Power System," "Radiation
Tests," "Heat Losses in Steam Distribut-
ing Systems," "Description of a large
Hot-water Heating System," "Quality of
Steam Supply as Affected by Use of
Superheat at Station," "Decentralized
Heating Plants," "Relative Economies of
One- and Two-pipe Heating Systems in
Buildings," "Sources of Trouble in Cus-
tomers' Installations," "Thermodynamic
Economy of Combined Power and Heat-
ing Systems," "Different Systems of Un-

derground Construction." One paper is
to be presented by the Cleveland Elec-
tric Illuminating Company, but the sub-
ject has not yet been announced.

NEW PUBLICATIONS

The Copper Handbook; A Manual of
THE Copper Industry of the
World; tenth annual edition. Com-
piled and published by Horace J.
Stevens, Houghton, Mich. Price,
green buckram, S5; full library
morocco, $7.50.
This well known work is a standard
authority on the subject of copper and
copper mines for the world. It has 1902
octavo pages and describes 8130 mines
and mining companies, with descriptions
of from two or three lines in the case
of deceased companies up to 21 pages, as
in that of the Anaconda mine, which
yields one-eighth of all the world's out-
put of copper.

The 24 miscellaneous chapters em-
brace the history, chemistry, mineralogy,
metallurgy, brands and grades, alloys
and substitutes for copper, with a copious
glossary- and a chapter of statistics con-
taining over 40 tables, thoroughly cover-
ing production, consumption, movements,
prices, dividends, etc.

Proble.ms in Thermodynamics and Heat
Engineering. By Edward F. Mil-
ler, Charles W. Berry and Joseph C.
Riley. John Wiley & Sons, New
York and London. Paper; 67 pages,
6x9 inches. Price, 75 cents net.
A pamphlet compiled primarily to sup-
plement the courses of instruction in heat
engineering at the Massachusetts In-
stitute of Technology. It is in no sense
a textbook; in fact, it contains no dis-
sertation at all upon the subject, only
the questions and answers being given.
These questions cover a wide range,
treating of the laws of thermodynamics,
thermodynamics of gases, saturated and
superheated vapors, flow of fluids, air
and internal-combustion engines, steam
boilers and engines, compressed air and
refrigeration and heating.

While the book is admirably adapted
for the particular use for which it was
written, still it would have found a wider
field for use had the problems been
worked out in detail, thus demonstrating
<he methods employed in solving them
rather than the mere answers.

In a 94-page book bearing the title
"Heating and Ventilating," the Green
Fuel Economizer Company, of Mattea-
wan, N. Y., has brought together the in-
formation required for the designing and
proportioning of hot-blast outfits for
heating, ventilating, drying, etc. The
book contains some two or three dozen
tables of temperatures required in rooms
for various purposes; heat transmission
through building materials; heat given
off by occupants and by lights; standard
sizes of hot-blast heaters; frictional re-

sistance of air washers; relative humid
ities; humidities and temperatures
throughout the United States; amounts
of air required for ventilation; equiva-
lent air pressures, velocities and horse-
powers; total weight of air at various
barometers and temperatures; pressure
and power consumed in friction; speed,
capacity and power of steel-plate fans;
friction of air through hot-blast coils,
etc. The text takes up not only the usual
details relating to the construction of
fans, heaters and heating and ventilating
systems, but also the calculation and
designing of piping systems, giving for
the latter two methods differing some-
what, namely, that used in the office of
the supervising architects at Washington,
and that proposed by Riltschel and cover-
ing the resistance of sheet-iron pipes
and of angles, bends, branches, grills or
registers, etc. There is also a chapter
on the loss of head of air flowing through
orifices and equivalent orifices, in which
is presented a method of combining the
resistances of ducts in parallel and series
connections analagous to Ohm's and
Kirchoff's laws for electrical circuits.
Another chapter gives the result of an
extensive series of tests upon Green's
"Positivflo" steam-heating coils, by means
of which heaters of suitable sizes may be
selected for any given duty. The gen-
eral illustrations of the book inculde not
only views of buildings equipped with
heating and ventilating apparatus built
by the Green Fuel Economizer Company,
but also detailed plans, elevations and
phantom views, showing the actual ar-
rangement of the fans, heaters, piping,
outlets, etc. Copies of this book wili
be sent upon request to architects, heat-
ing and ventilating engineers and others
concerned v.-ith the purchase, design, or
operation of heating plants.

BOOKS RECEIVED

Practical .Marine Engineering. Third
edition. International Marine Engi-
neering, New York. Cloth; 794
pages, 5"ix9 inches; 350 illustra-
tions; tables; indexed. Price, S5.

Short Course in Electrical Testing.
By J. H. Morecroft and F. W. Hehre.
D. Van Nostrand Company, New
York. Cloth; 154 pages, 5'ix8J:}
inches; 46 illustrations. Price, S1.50.

Maximum Production in Machine Shop
and Foundry. By C. E. Knoeppel.
The Engineering Magazine, New
York. Three hundred and sixty-five
pages. 4' 4x7' J inches; illustrated;
indexed. Price. $2.50.

Handbook on the Gas Engine. By Her-
man Haeder and W. M. Huskisson.
AlcGraw-Hill Book Company, New
York, and Crosby. Lockwood & Son,
London, England. Leather; 317
pages, 6'<x9'4 inches; illustrated;
tables; plates; indexed. Price, $5.

\'ol. M

NKW YORK, HKCKMBER 12, 1911

»«T understand three languages," said an old-time

I

engineer, "German, English and Powerhouse."

"Powerhouse?" we inquired, wondering what he
could mean; "what is that?"

"It is the language of engines, generators and
pumps, and of boilers and furnaces. And it is learned
only after long and studious intimacy with tlie ma-
chines and apparatus that speak it.

"The novice can hardly distinguish one power-
house sound from another, much less tell what any
particular one signifies— he simply hears one con-
fused jumble of noise.

" Not so with the engineer. He knows the soft
tune which the contented, well-lubricated generator
hums and he knows instantly when that tunc changes
to a complaint. And, knowing these things, he also
knows what to do to stop the complaint.

" Each piece of apparatus speaks in a differenr
dialect.

lution. The crosshead may be truly cross, and make
that fact known by its constant clatter. The piston
may be loose on the rod, or a ring on the piston itself
may be loose. The steam cylinder may .suffer from
an attack of water. The valves may be seized with a
touch of rheumatism brought on by lack of oil. No
matter with what physical trouble the engine suiTcrs,
it seems to have some sound by which it can make that
trouble known

"Then, there is the chirography — the handwriting
— of the various machines. Of late j'ears this has
grown to be a most important study, for by it we are
enabled to learn much that is valuable about the
character and habits of a piece of apparatus.

" Perhaps the oldest and most widely known
instrument, by means of which a machine is able to
give us a written message, is the steam-engine indicator.

"The diagram that the indicator draws is a truth-
ful diary of what the engine does during a certain time.
By means of it the engineer is able to learn much
that is important if he has any desire to operate the
engine economically

"The imprisoned steam in the boiler, struggling
with persistent and gigantic effort for release, makes
hut little sound until, by redoubled effort, it forces
oi)en the safety valve and gains its release to the
free air. Then what a mighty and triumphant roar
it does set up!

"The steam pipes, how they chatter and com-
plain when they are forced to drink too much water!

"The recording steam gage, vacuum gage, watt-
meter, water meter, draft gage, CO, machine, ]1)to-
mcter, thermometer, etc., are other devices which
enable power-plant apparatus to give us a written
message of what they arc doing and how.

"The writing made by these instruments is quite
simple and ea,sy tf> read But the significance of that
writing is not always so easy to fathom.

"Then, there is the dialect of the engine. Tliis
piece of apparatus is snbjcct to many ills, and for each
it has a special cry. The shaft may be hmse in the
bearings, and boom out a deep protest at each revo-

"To successfully understand the spoken and
written language of the power house requires cxin-ri-
encc, thought and study. To be a master of them
is worth real money."

POWER

December 12. 1911

Power Plant of the Ayer Mill

When the American Woolen Company
decided to erect another mill upon the
plot near its Wood mill at Lawrence,
Mass., it was at first proposed to drive
it electrically from the power plant of
that mill. A woolen mill, however, has a
great deal of use for low-pressure steam,
and the cheapest known way to produce
power is by the use of a steam engine or
turbine as a reducing valve between a
high- and low-pressure steam system.
Incidentally it may be said that it takes
as many boilers to supply steam for heat-
ing the water used in the dye house and
in the manufacturing processes at the
Ayer mill as it does to run the turbines
at their rated capacity while steam is
being taken from their second stages for
heating the same amount of water.

Because of this, and of the imprac-
ticability of bringing steam from the
Wood mill for use in the dyeing and fin-
ishing departments, it was very desir-
able that the Ayer mill, as the new struc-

By Warren O. Rogers

In designing this power
plant every precaution was
taken to guard against a
shutdown. Labor-saving
and safely apparatus is in
evidence throughout the
plant.

The two 2^00-kilowatt
turbines are made with a
special casing in which
valves arc so placed that
steam can be taken from
the second stage and used
for heating water in the
mill.

tube boilers and turbine-driven generators
as they are more compact in plan than
horizontal tubulars and piston engines.
It also involved the use of overhead coal
storage with its attendant coal-conveying
machinery, and this again pointed to the
use of mechanical stokers. The result
has been that the installation is of the
most advanced and elaborate sort in
which none of the newer type of power
apparatus and appliances is lacking. In
this respect it is the antithesis of the
Wood mill plant erected some five years
ago and an excellent opportunity is af-
forded to compare the cost of power pro-
duction in these two extreme types of
plant.

Tl'rbines

In the turbine room there are two
five-stage horizontal Curtis turbines, each
of 2500 kilowatts capacity, and there is
room for one more of the same size. They
run at a speed of 1200 revolutions per

_, ,

i^"^!^ '

■ " '- .■--.■!ii."_." \: Y« •"'

L^^b^^^^b

■i -%^, ^ ^ :.i' ■ _i

bjmuil

^M\ :-,^'- : ' ,

I_l

^

— "

^^

^>--<=-

Hwm

Fig. I. Two 25iK)-kilii\\ ait Steam Turbines Fitted with Special Gate Valves in the Top Casing of the Second St.ace

ture is called, should have its own power
plant. After a study of the conditions
Charles T.. Main, the designing engineer,

decided that he could get an adequate
plant upon the limited ground space
available. This involved the use of water-

minute with a steam pressure of 175
pounds. The steam valves are hydraulical-
ly operated by means of oil under a pres-

December 12, 1911

P O W E R

877

sure of 80 pounds per square inch, the
oil pressure to the bearing being main-
tained at 20 pounds.

In Fig. 2 is shown a sectional view of
one of the turbines. Both are fitted with
specially designed upper casings in
which are arranged gate valves opening
to the second stage. Through these
valves steam is taken from the turbine at
a pressure of between 6 and 7 pounds
and is delivered to the dye house through
a 14-inch pipe; the exhaust from the
auxiliary turbines in the basement is
also discharged into this main. The ex-
haust pipes of the two main turbine units
connect with a 30-inch spiral-riveted at-
mospheric exhaust pipe, each fitted with
an automatic relief valve. Both turbines
are supplied with steam through either
of the two 10-inch steam mains. The

condenser turbines are of 90 horsepower
each.

There has been added to the original
design a filtering system through which
all the water from the condensers is
passed. The filter consists of a concrete
basin with a system of collecting pipes
with brass nozzles buried under sand and
quartz. There is also in the filtering
well a heating pipe supplied with steam
through a reducing valve from the high-
pressure system in order to supply hot
water to the dye house when the turbines
are not running. It requires an 8-inch
pipe to supply enough live steam at a
reduced pressure of 10 pounds to heat
the water used in the dye house and the
slasher room.

Two 12-inch rotary pumps cir-
culate the water from the filter to
the dye house, each being capable of
delivering 3600 gallons per minute when

economizer it is delivered to the boilers
through a 5-inch Venturi meter. The
boiler-feed pumps are equipped with
pump governors. There are two 6-inch
feed lines running from the pumps to the
economizers and two feed lines are con-
tinued over the boilers having valves so
arranged that in case one line gives
trouble the other can be used. The feed
pumps have three sources of supply, the
one most used being a 12-inch cast-iron
pipe running to the hotwell. The pipe is
reduced to 10 and 8 inches at the two
end pumps respectively. The other two
suction lines are of 6-inch and 10-inch
cast-iron pipes; one is connected to the
city water main and the other to the canal
penstock.

The two feed-water heaters are con-
nected in tandem so that the feed water
can be passed through either or both. The
exhaust from the feed pumps is used in
these heaters and is not sent to the dye-
house main as the oil would make the
water unfit for textile use.

At the right of the illustration is shown
a 10 and SJj by 12-inch service pump

Fig. 2. Sectional View of One of the Five-stace Tlrbines, Showing Valve in Spicial Casing

pipe leading to the dye-house main is
fitted with an atmospheric exhaust valve
which discharges into a spiral-riveted ex-
haust pipe with an exhaust head.

Each turbine exhausts into a separate
LeBlanc condenser which discharges the
condensed steam and condensing water
into a hotwell at a temperature of 105
degrees. A vacuum of but 27 inches is
maintained with this temperature of dis-
charge water as a high hotwell tempera-
ture is more economical and of greater
importance than a higher vacuum. The

running at a speed of 1500 revolutions;
each is driven by a 150-horscpower steam
turbine, and one is held as a reserve unit.

Pumps

All other pumps are located in a base-
ment pump room which rtins the entire
length of the power plant, as shown in
Fig. 3. BcRinning at the left hand of the
illustration, there arc three 12 and 7 by
12-inch boiler-feed pumps which take the
feed water from a hotwell. and after il is
fnrccd throueh one of two heaters and an

which is connected to the sprinkler sys-
tem. This pump is also piped so that its
discharge can be used for feeding the
boilers. A 10x8' > -inch scr\icc pump
supplies water for washing purposes and
there is a two-stage ccnirifugal pump di-
rect-coupled to a high-speed steam engine
running at a speed nf 3,S0 revolutions per
minute which is used in the winter only
and circulates hot water for healing pur-
poses through the healing system. The
circulating water is healed in a closed
heater and after making the circuit of the

878

POWER

December 12, 1911

system it returns to the heater with a
drop of about 10 degrees in temperature.
There is also a single-stage pump driven
by a 50-kiIowatt induction motor which
is used as a reserve unit for the heating
system.

All of the water removed from the
heater connected to the heating system is
taken care of by a 7 and 4'/I. by 10-inch
outside-packed pump, which sends the
water from the heater direct to the boilers
through an independent feed pipe.

A small air compressor, the steam end

and exhaust pipes are suspended from
the basement ceiling, and to facilitate
opening and closing the larger valves the
valve stems have been fitted w'ith sprocket
wheels and chains, the latter coming with-
in reach from the floor. This idea is car-
ried out on the main stop valve on the
steam pipes which are connected to the
second stage of the turbines.

There are two auxiliary lines of steam
headers, one 6 inches and one 10 inches
in diameter. The exhaust steam from
the auxiliary turbines is carried through

are fastened to the wall by lJ4-'nch ex-
pansion bolts. A steel casting is secured
to the exhaust pipe above the brackets
and fits a second steel casting which is
bolted to the first. Two bolts, each 1^<
inches in diameter at both ends and 2
inches in diameter for a distance of 8
inches below the steel casting, are used
as shown. On the large portion of the
bolt an adjusting nut and jamb nut are
screwed. A cast-iron washer comes next,
followed by a ^s-inch round steel spring
having when free a pitch of 1^ inches

w.

8 C.I. Pipe

4'"^^^^^^\ — IT-TT- — m'C.l.npe li

Fig. 3. Piping of Water-supply, Boiler

of which is 10x10 inches, supplies air
for factory use, blowing motors, etc.;
the air end has a 12xI0-inch cylinder.

Piping

In Figs. 4 and 5 are shown a plan and
elevation of the steam and exhaust piping
of the plant. The three boiler-feed pumps
exhaust into a 10-inch pipe which is con-
nected to both of the feed-water heaters.
The main-pump exhaust line is reduced
to 5 inches at the far end. The steam

a 14-inch pipe to the feed-water heaters
which are set on the boiler-room floor
back of the boilers. An examination of
the piping plan shows that practically
every possible avenue has been closed
against a shutdown due to pipe-line fail-
ure.

The manner in which the heavy
steam and exhaust pipes are sup-
ported is interesting. In Fig. 6 are
shown the spring supports of the
30-inch exhaust pipe. Heavy brackets

and an outside diameter of 5 inches. Each
of these bolts fits in a saddle which rests
on the brackets; the springs rest in a
seat in the saddle. The nuts are so ad-
justed that the weight of the exhaust
pipe is carried by the springs. This re-
moves undue strains from the lower por-
tion of the exhaust pipe and its connec-
tion to the condenser.

An altogether different arrangement
has been used in connection with the
counterbalancing device on the two 10-

December 12, 1911

POWER

879

inch steam mains and on the 14-inch
exhaust pipe. Referring to Fig. 7, the
lower steam pipe is clamped by a 5sx3-
inch sectional band having two "s-inch
side rods bolted to a channel bar above
the upper steam pipe. A 1 -4-inch rod Is
also bolted to the channel bar and is fit-
ted with a tumbuckle at the upper end;
the turnbuckle is bolted to a steel lever
on which counterweights are placed, each
weighing about 54 pounds. The lever
is pivoted on a steel pin driven in the
lever and seats on a steel-bearing plate;

n. 1 _-_ — 1

pivoting post at the bracket a similar
pin is driven in at the short end and
supports the links, each of which is
connected by a "g-inch rod to the flange
of the pipe. The general arrangement
is shown in the illustration.

Boilers

There are eight 600-horsepower Heine
boilers with Murphy mechanical stokers,
each 8 feet deep and 12 feet wide, the
largest stokers made by this manufac-
turer. Two engines drive the stokers on

than if the riveting of the headers to the
steam drum and the rolling of the tubes
were done from below. After the boilers
were assembled they were turned over,
thus bringing the steam drums on top and
the boilers blocked up ready for the brick
setting to be put in place. Each boiler is
equipped with a Foster superheater which
superheats the steam 125 degrees. There
are four economizers, one for each set
of two boilers. The furnace gases can
be bypassed to the brick stack, which
has an internal diameter of 12 feet and

.rri

Feed and Blowoff System

this plate is driven Into a slot in the
bracket secured to the brick wall by five
1-inch expansion bolts.

The upper pipe Is fitted with a sectional
ring which Is bolted to a single I'i-lnch
rod with a turnbuckle at the other end
and is attached to the counterweight arm,
as shown. A similar arrangement has
been provided for the 14-Inch exhaust
pipe, as Is shown In Fig. 8. In this In-
stance the counterbalance lever Is forked,
and besides being fitted with a steel

six of these boilers and one engine drives
the stokers for the other two boilers.

In Fig. fl Is shown a view of the boiler
room. The furnaces arc of the dutch-
oven design and arc supplied with coal
from above. Space has been reserved
for four additional boilers at the far end
of the row.

Owing to the size and as a matter of
convenience, these boilers were assembled
bottom-side up from the usual position.
This enabled the workmen more freedom

is 265 feet high. The draft Is i'^t inch
over the fires.

Coal and Ash Conveyers

Above the boilers Is located a .VXX)-
ton coal pocket which Is divided in the
center by an ash bunker. Coal is dis-
charged from the coal cars on the track
outside of the boiler room to a crusher
which delivers it to a bucket conveyer
which in turn deposits the coal on a
belt conveyer running over the coal

880

POWER

December 12, 1911

pocket. Coal is taken from the pocket
into a traveling weigh hopper and is dis-
tributed to the various stokers.

A vacuum conveyer handles the ashes
from beneath the stokers as well as soot
from the economizer and conveys them all
through a O-inch pipe to the ash bunker
located above the boilers. The ashes from
the ashpit are hoed into an opening of the
vacuum system through a rear outlet and
the soot from the economizers is hoed
out into connections leading to the vac-
uum system. Ashes from the ash bin can
be delivered to cars on a track on the
outside of the building or loaded into

High

carts and carried away. The arrangement
of the ash and coal bunkers, ash-con-
veyer system and elevation of the boiler
and turbine rooms are shown in Fig. 10.
The ash bunker, w-hich is some 50 feet
across and constructed of reinforced con-
crete, is tight enough to allow a vacuum
of 14 inches of water to be maintained
in it. A rotary exhauster driven by a
35-horsepower motor is used for this
purpose.

m^//////////A

Fig. 4. Pl.^^n of the Steam and Exhaust

C

4 Steam fo
Hot Wafer Pump
Engine

?j Exhausit

'iir''''''''W''''''''''''W'''^^

^\V\V\\\\\\'^\\\'^'^\\\\\\N^\\\\s\\X^^^^

Automatic Receiver
and Pump

Fig. 5. Elevation of Steam and E.xhaust

December 12, 1911

P O W E R

881

Piping in the Turbine and Boiler Rooms

Piping in the Boiler and Turbine Kw.ms

882

POWER

December 12. 1911

kilowatt alternators. Two of these units
are each driven by a 60-horsepower in-
duction motor and the third is driven by
a small steam turbine. Their voltage is
125.

At one side of the turbine room is the
switchboard of the plant. The main
generator switches and circuit-breakers

Sequel of Rochester Mud
Drum Explosion

Brief mention was made in the July
26, 1910, issue of the cast-iron mud-drum
explosion at one of the power houses of
the Rochester Railway and Light Com-
pany, Rochester, N. Y., on July 16, 1910,

in which the boiler was wrecked, one
man killed and two injured. The cast-
iron mud drum was in one of eight Cahall
boilers installed in 1901.

On the morning of the accident and
about two hours prior thereto, the pres-
sure exceeded 170 pounds, the boilers
being allowed 175 pounds by the Fidelity
and Casualty Company. The fires under
the boiler had been banked about half

© t>J

Fig. 6. Spring Support for 30-inch Exhaust Pipe

Fig. 8. Counterbalance on 14-inch
Pipe

an hour before the accident; fresh coal
had been put on and feed water at a
lower temperature than the water in
the boiler was injected; the chimney
damper had been closed, confining the
gases. Just before the explosion a fire-
man observed smoke and flame issuing
from the front of the boiler near the
stokers and was trying to open the

are mounted upon a framework at the
side of each generator, as shown in Fig.
1. The switchboard proper carries the
necessary recording instruments and
switches for the lighting and motor cir-
cuits leading to the mill. Above each
switch is a card which designates the
circuit and the motor load carried on the
circuit.

Back of the panels are located the bus-
bars and cable connections, the latter
dropping to the basement and running
to the mill upon cable racks. These racks
are constructed of angle irons to' which
wooden crosspieces are attached. The
cables are clamped to these wooden
crosspieces.

A noticeable feature of this plant is
that nothing has been crowded into an
inaccessible place and the plant is light,
roomy and well ventilated. There are
few, if any. industrial power plants which
are equipped with so many precautions
against a shutdown or are fitted with so
many labor-saving and safety appliances
and so many means for keeping track
of performance. There are at least a
dozen recording gages about the plant
for different purposes, provision is made
for weighing the coal and metering the
water to each boiler, and it is to be
hoped that some interesting data upon
actual power-plant results will be evolved.

Fic. 7. Counterbalance on IO-inch Steam Pipe

December 12, 1911

POWER

883

damper when the explosion occurred. At
the time of the accident the pressure was
168 pounds, as shown on the gage, or
175 pounds on the mud drum, due to the
weight of the water.

Suit was brought by the heirs of Frank
E. Quirk, the man killed, and the Supreme
Court of Monroe county awarded dam-
ages in the sum of 510,000. An abstract of
the finding by the jury is given herewith.

Fic. 9. Boiler Room Which Contains Eight 600-HORSiiPO\vER Water Tube
Boilers

In the jur>''s opinion, a cast-iron mud
drum was not reasonably safe in a boiler
having 168 pounds pressure and its use
was negligent. It further appeared that
the usual inspection revealed no defects
in the mud drum; that it was kept in re-
pair and sustained pressures of from 120
to about 183 pounds, which would be
from 126 to 190 pounds on the mud drum.
The safety valve was set to blow at 165
to 170 pounds.

The defense contended that the boiler
was bought from a reputable maker and
that there were many others of its type
in use at even higher pressures.

On behalf of the plaintiff. Prof. R. C.
Carpenter, of Cornell University, testi-
fied as to the unreliability and brittleness
of cast iron. He said there were some-
times defects in castings which could
not be discovered by any test usually
applied by boiler inspectors or, in fact,
by any test which would not destroy the
drum. Professor Carpenter did not con-
demn the use of cast iron in steam fit-
tings except in large parts, such as mud
drums, as they are subject to the varying
conditions of strain and temperature of
the gases of the furnace.

Several inspectors testified as to the
uselessness of the hammer test for cast
iron, and that the hydrostatic test might
reveal defects, but it was not sure.

Professor Carpenter claimed that the
use of cast iron in an apparatus in which
disaster was so certain in case of ex-
plosion was negligence; that as steel
drums had been generally used for sev-
eral years prior to the accident, they
should have been used instead of cast
iron. In this opinion he was sustained
by the jury.

Fig. 10. Cross-section of the Power Plant

POWER

December 12, 1911

Erecting a Large Engine Flywheel

In the engine shop the handling of
large castings presents no special diffi-
culties as every facility for the purpose
is at hand. There are, perhaps, many
mechanics who have given no thought to
the ways and means that would be em-
ployed for unloading, moving and placing
the parts of an engine in their final
position. Likewise many men having to
do with engines would go about the work
of removing or replacing heavy parts
very awkwardly, if they were suddenly
confronted with the necessity.

Yet this is a task which is more than
apt to fall to the lot of any mechanic or
engineer, although the loading of a
bulky and unwieldy casting onto the
"boat" and running it on rollers and
skids from the car to the foundation,
looks simple and easy when the well
trained erector is doing it.

Where Conditions Become Difficult

Consider a medium-sized Corliss en-
gine having an 18x3-foot flywheel made

By F. C. Holly

Specific directions , with
illustrations, upon how to
imload and erect a flywheel.

This information is
adapted especially to the
engineer who is frequently
confronted with this task
without having any special
appliances for performing
it.

appliances, how many operating engi-
neers could tackle the job of unloading
and erecting this wheel in full confidence
and in a reasonable length of time with-
out delays or mishaps. But given one
or two screwjacks of different lengths, a
decrepit crowbar, a sledge hammer and
a set of rope falls, some old rope and

SOiME Wise Precautions
In loading a segment upon the "boat"
or skids, care must be taken not to over-
turn it. To prevent this it is a wise pre-
caution to keep a guy line on each side
while raising. Jacks should be set as
in Fig. 1 ; the head block being hewn
in the center to fit the spoke and a jack
placed under each end, raising evenly
one end of the wheel at a time and fol-
lowing up carefully with safety blocks.
The"boat"can be made of 3x12- or 4x12-
inch planks or any wide timber which
may be on hand, 19 feet long and 4H
feet wide, laid together with four cross-
pieces, as shown in Fig. 2, but not fast-
ened until later.

The safest manner of inserting the
long "boat" skids under the wheel is
shown in Fig. 3. The wheel should be
raised and blocked to a hight equal to
the thickness of the boat B, Fig. 2, plus
the diameter of the rollers. Use the'
long runners and a crosspiece for block-
ing at one end, as shown in Fig. 3, allow-

^^^, Block same
-r—./ Thickness as

i .-■

=— ;-H — ; ; ---—'"^

\

^'1

A

1,

i -^ — -=-— " — ^~i i : -=— "= — ! :!

Fly Wheel Pit

Figs. I to 7. Various Stages in Erecting Flywheel

in two segments. This sized wheel is
usually shipped on a flat car with the two
halves standing side by side and sep-
arated by distance pieces and clamped
together by bolts. Given a good set of

the choice of the best out of a pile of
old misfit lumber, some engineers would
get "cold feet" before starting. Yet these
are by no means uncommon conditions
which the erector is obliged to face.

ing the other ends of the runners to
swing out clear of the block, which
should be no longer than the width of the
pulley rim.

With the jacks as shown, the wheel

December 12, 1911

may be raised and the block X turned
around parallel with the runners and
left there for safety. With a sledge
hammer the runners can now be driven
under the wheel at this end. A cross-
piece and roller should be made
ready, and as block X is drawn out of
the way the crosspiece and roller should
be inserted. The wheel should at no
time be allowed to rest upon the jacks
without being blocked.

Block Z can now be removed and as
many more rollers inserted under this
end as will go. The rollers should be
chal'.:ed and the center crosspieces put
in, after which the jacks can be lowered,
the other end of the wheel raised, block
Y removed and the rollers placed.

Handling the Loaded Wheel

The loaded wheel is showm in Fig. 4.
With very heavy wheels it may be neces-
sary to have blocking halfway between
the rim and hub, as shown. The end
crosspieces should now be secured to
the runners with one lagscrew in each
end. If the wheel is flanged, a safe
bracing should be employed to prevent
upsetting, as shown in Fig. 5. Another
method is to brace from the edge of the
"boat" to the center spoke on a six-
spoke wheel.

POWER

Lowering the Wheel

On arriving at the engine, the shaft
being already in place, with the journal
caps bolted down, the wheel can be low-
ered and the runners removed by the
same method reversed as used in loading.
Guy lines should be kept taut and a num-
ber of lx6-inch boards and other block-
ing, as long as the full width of the
wheel face, should be provided so that
the wheel can be blocked every inch of
the way down. Fig. 6 shows the wheel
over the crank shaft with the blocking
and platforms ready upon which to work
while lowering.

After the segment has been lowered
to the shaft, clamps should be made of
6x8-inch hard wood and secured as
shown in Fig. 7, the bolts belonging to
the hub being used for the purpose.
Three sets of blocks should be attached
to hold the wheel level while the tim-
bers and blocking are being removed.
When everything is clear the segment
can be rolled over into the pit, great
care being exercised in having all the
hitches carefully made and the fall lines
securely snubbed preparatory to quickly
and smoothly slacking away.

Tackle No. 3, in Fig. 7, sustains the
weight as the wheel is drawn over by

the bolts inserted
drawn up to place.

885

and the first half

40 ^g;^^^^v^^

Fig. 8. Alternate Method of UNLO^niNc Flywheel

Much faster rolling will be accom-
plished by the use of the largest rollers
at hand up to 6 inches in diameter. When
oak or other hard-wood rollers cannot be
had, 4' J- or 5-inch gas pipes are good
substitutes. Plenty of rollers should be
used to evenly distribute the weight,
thus making easy rolling.

How TO Build the Runway

The runway should be carefully built
of timber of ample size to support the
load, and be carefully lined and blocked.
Getting ready is the longest part of the
erector's job. and the novice should not
make the error of starting the casting
on its trip without due preparation, as
the actual work of moving should occupy
only a few moments under favorable
conditions, while a poorly built runway
may cause it to take many hours. Abrupt
angles and bends in a runway should be
avoided and the timbers should be lapped
and not joined end to end.

tackle No. 2. The weight increases as
the wheel is turned and No. I then re-
ceives part of the strain until No. 2
engages, when No. 3 should be changed
to the position shown in the dotted lines;
this change should be made before the
lines fall over edge E.

When to Use Jacks

It sometimes occurs that three sets of
rope blocks suitable for the work can-
not be obtained in the community where
the engine is to be erected. In such a
case, on a lighter wheel, heavy snubbing
lines may be used, but if no kind of
tackle is available the wheel must be
turned over and lowered into the pit
by means of jacks, which is a slow and
laborious process.

The first segment having been lowered
in the manner described, if may then he
allowed to rest on blocks on the bottom
of the wheclpit and the second seemenf
may be run In and lowered to the shaft,

Another Method

Another method of loading the wheel
is illustrated in Fig. 8. The skids are
strapped to the sides of the wheel by
means of bolts running through both in
the manner shown. Care should be
taken to use bolts large enough to per-
mit tight clamping of the timbers against
the wheel as a slip may be disastrous
and in handling very large and heavy
wheels blocking should be used under
the spokes as an additional safeguard.
A third bolt may be used in the center,
passing through the shaft hole and clamp-
ing the timbers against distance block-
ing between them and the hub. If the
center boit is not used the straps should
he nailed across from one skid to the
other to prevent side buckling.

This method requires less jacking but
unless very heavy timbers are used the
broad surface, so desirable for smooth
and easy running, is not presented to the
rollers. After the skids are thus placed
the wheel may be mounted upon the roll-
ers in the same manner as before de-
sc-ibed.

Engineers' Wages in China
By Walter H. Adams*

I have been interested in reading the
remarks of engineers concerning wages
that have appeared from time to time in
Power.

I think a few words regarding the scale
of wages that I pay my men here may
bring the "yellow peril" near to the men
in the power plant.

I have a small plant of 30 kilowatts
capacity for lighting the university. This
rame plant is used for pumping water
for our water system of 25,000 gallons
daily capacity and for supplying heal to
our main building of 25 rooms.

The engineers and firemen are under
my direct super\'ision. Under me is my
chief engineer, who speaks, writes and
reads English rather imperfectly. He
receives $14.70 gold every month. His
duties are to supervise all the other men
and act as my interpreter. He can do
electric wiring, pipe fitting and machinist
work with very little supe^^■ision. His
hours are 8 a.m. to 1 1 :30 p.m.

Next comes the first assistant engineer,
who receives the maeniflccnt wage of
S8.40 per month. His hours are the same
and his duties are similar, except he does
not have the responsibility and talks no
Fnglish.

The second assistant engineer receives
'^3.80 per month. He is assistant, oiler
and wiper, and is a youth whom the
chief engineer breaks in as an engineer.
Then there is No, I fireman. His hours
for firing are from 4:30 p.m. till 11:30

'.'".'"/T*,'"^ "f, .mp'-h-nlriil rneliiMTlne. Im
pi>rlnl ITI ^nne I tilvrr.Hr Tirnitsln. C'hinn.

POWER

December 12. 1911

p.m., but he is expected to be on duty
from 8 a.m., and clean the apparatus in
the boiler room and the boiler which is
laid up at the time. He is responsible
for the condition of the boiler room. He
receives S5. 10 per month. An assistant
fireman helps No. I fireman and re-
ceives $4.20 per month. A "coolie" does
the general cleaning and looks after the
fires vfhich we l^eep in our filters and
pump houses to prevent freezing. He is
on duty day and night as long as it is
necessary to look after the soft-coal fires.
He receives .$3.40 per month.

In the winter an additional fireman is
employed who looks after the boiler from

4 a.m. till 3 p.m., during which time it
is used for heating. He receives $4.20
per month. This totals $43.80, or less
than one man would receive in the United
States.

These men do all the new wiring, keep
all wires in repair on the circuit, supply
50 arc lamps with new carbons when
necessar>% do ail the pipe work and they
will do all the forging and machine work
when I get my machine shop ready.

Of course, all this work, or the greater
part of it, could be done by two men in.
the United States, but the amount paid
as a total is less than that ordinarily
paid to a good fireman.

The only additional thing provided by
the university is unhealed quarters. As
these are unfurnished, I have often found
my men sleeping on their beds in the
coal bin or, in winter, on the top of the
boilers. The beds consist of two saw
horses with two planks placed on them.

I allow each man one day off every
week but he has to return before evening
so as to be ready for his work. Even
this is the exception out here, where
everyone works 365 days in the year.

When a man at home gets a "grouch"
and thinks the boss is not treating him
right, just let him think of the workmen
out here and forget the "grouch."

British-Canadian Power Company

The rich silver mines of the Cobalt
district were discovered in 1904, and
although at first it was believed that
they were not extensive deposits, the
camp has since developed into one of the
most important of the world's producers
of silver. During the year 1910 approxi-
mately 30,000.000 oz. were produced and
the production for 1911 is estimated at
about 35,000,000 ounces.

Steam Power About $160 per Horse-
power-year
One of the most interesting features of
this camp is the development of power
en a large scale, for supplying air and
electricity to the various mines. The
camp embraces an area of approxi-
niately seven square miles, in which there
are 30 shipping mines besides several
nonshippers, and it lends itself readily
to the large development of power. The
distance of the Cobalt district from the
coal-producing centers is great and as

By G. C. Bateman*

One of several uvter-
power developments which
have ciit Cobalt power costs
from about $i6o to $50 per
horsepower-year . Electric
poiver transmitted at 44,000
volts. Bleeder valves in air
lines warmed by electric
heaters.

Total Develop.ment, 15,000 Horse-

POW ER

The cost of power became a serious
consideration in the cost of mining and

E. A. Wallberg and F. J. Bell, of Mon-
treal. This company secured a valuable
water power on the Matabitchewan
river, distant about 25 miles from Cobalt.

The main power dam is 860 ft. long
and 50 ft. high at its deepest point. It
raises the water 40 ft. above its former
high level and gives a working head of
312 ft. It is estimated that a total of
15,000 horsepower can be developed.
Several lakes above the dam have been
utilized for storage purposes, so as to
eliminate as far as possible the danger
of a water shortage.

By means of an intake canal the water
is diverted to two steel penstocks, each
5 ft. in diameter and 1075 ft. in length.
Each penstock supplies water to two tur-
bines. The power house is a solid con-
crete structure 57x105 ft. and is fitted
with travelling cranes. The turbines are
of the horizontal reaction type, con-
sisting of a single runner in a spiral case

Fic. 1. Power House and Main Concrete Dam of British Canadian Power Company, on Matabitchewan River

transportation is all-rail, the cost at the
mines is necessarily high, averaging be-
tween $6 and $6.50 per ton; consequently
coal-generated power is costly. A series
of tests run at the dilferent mines put
the average cost for the camp at between
$150 and $175 per horsepower-year.

several companies were formed to de-
velop the large water powers near the
district, for the purpose of supplying air
and electricity to the mines. Among
these was the British-Canadian Power
Company, formerly known as the Mines
Power, Ltd., which was promoted by

with a speed of 600 r.p.m. and rated at
2750 b.h.p. each.

The electrical equipment consists of
four 1875 kw. alternating-current gen-
erators, direct connected to the turbines.
There are two exciters, each direct con-
nected to a Doble impulse water wheel,

December 12, 1911

POWER

887

rated at 180 h.p., 475 r.p.m. To insure
perfect regulation, high-power governors
are installed. The current is three-phase,
60-cycle, and is generated at a pressure
of 2200 volts. By the use of step-up trans-
formers the pressure is increased to
44,000 volts, at which potential it is trans-
mitted to the power stations at Cobalt
and South Lorrain.

Aluminum Transmission Wires Used

There are two separate three-phase
transmission lines 35 ft. apart over a
right-of-way 135 ft. wide. This right-of-
way has been entirely cleared, and all
tall trees on each side have been cut
down. The conductors are stranded
aluminum cables, and the poles are
equipped with high-tension porcelain in-
sulators that were subjected to the most
severe tests before being used. The con-
ductors on each pole line are of sufficient
capacity to carr>' the whole power load,
thus eliminating any danger of a shut-
down due to a break in the line. The
main transmission line is equipped with

Fic. 2. Transmission Lines to Cubai. i

a private telephone system and patrol-
men are stationed at intervals.

At the Cobalt camp two brick and
concrete substations have been erected,
one at Cobalt lake with a capacity of
5500 h.p. and the other at Brady lake
with a capacity of 3200 h.p. Each sub-
station is equipped with all the neces-
sary step-down transformers, lightning
arresters, switching devices, etc. Electric
current is delivered to the customer at
2200 volts, and by means of line trans-
formers is reduced to 550 volts for motor
service and 110 volts for lighting.

A substation was also built at South
Lorrain to supply electric power to the
mines of that section, which was de-
stroyed by fire a short time ago, but has
since been replaced by a concrete fire-
proof structure.
Both Meter and Flat Rates Used

Power Is sold to the mines on a meter
basis, with prices varying for the amount
consumed and the class of service, or it
is sold at the flat rate of S.V) per horse-
power-year. This rate is high in com-

parison with prices for power in other
sections of the country, but is eminently
fair when the immense cost of the under-
taking is considered, and the fact that a
much shorter life must be looked for
than would be the case were the plant
supplying power for industrial purposes.
At both the Brady Lake and Cobalt
Lake substations, are identical compres-
sor plants, each consisting of two 2-
stage air compressors, each having a
capacity of 5000 cu.ft. of free air per
min.. and each driven by a 1000-h.p.
motor. When the compressors are run-
ning at full load they each take 1020
h.p. The compressors are equipped with
the regular intercoolers, and each sub-
station is equipped with an e.vtra large
water after-cooling system. From this
the air passes through a separator, and
from there through an air-cooling sys-

which are excessive, the lines were zig-
zagged and, although the plant has been
in operation for two years, no trouble
has as yet been experienced. In all there
are about 15 miles of main lines and
branches.

In the pipe lines there is at times a
small accumulation of water. This is
not of sufficient quantity to affect the
mines, but as the water collects in the
bottom of the hollows of the lines, it
would freeze in the winter time and
stop up the pipes. At the lowest point
of each hollow, there is a '4 -in. cock that
is left open just enough to allow the
water to escape. In the winter time the
pipe at the point where the cock is in-
serted is warmed by an electric heater,
thus preventing the water from freezing,
and keeping the cock open. The air is
delivered to the mines at 100-lb. pres-

Fic. 3.

Two 100-HORSEPOWER COMPRESSORS OF BRITISH CANADAN

Power Company

tem. This latter system is not used in
the summer, as the high temperature
renders it useless, but it is in contin-
uous use in the winter time.

The air is delivered through steel
pipes, with diameters varying friyn 3
to 10 inches, and the two substations are
connected by a 10-in. main. All the
pipes are lap-welded, and the larger sizes
come in 40-ft. lengths. They are fitted
xiih wrought-iron forged flanges welded
on. and each pipe has a weld in the cross-
section made by the oxyacetylene pro-
cess, and they have been tested to a
pressure of 300 lb. per sq.in. All fittings,
valves, etc., are made of steel.

Piprs Ziczacceo; No Expansion Joints

When this line was first under con-
sideration it was decided tlot to install ex-
pansion joints, as they wore not con-
sidered Rufflciently reliable. To take
care of the expansion and contraction.

sure and is sold at the rate of S2 per
drill per shift.

Operations on this plant were started
in the first part of ,Fune, 1909. and the
first power was turned on Alarch 17. 1910,
whict^ is an enviable record for a plant
of this size. Air and electric service is
now being supplied to 37 mines and
concentrators. In addition to this the
company supplies power for the electric
railway between Cobalt and Haileybury,
and furnishes electricity at wholesale
rates to the Cobalt Light, Power and
Water Company, which resells to the
town of Cobalt.

There has rccrnllv been assigned to
the Allis-Chalmers Company, Atilwaukcc.
Wis., a patent for a turbine in which
an exhaust pipe extends from an en-
gine and is divided into two paths, one
of which communicates with a condenser
and the other path leads to the turbine.
A governor controls valves which limit
the flow through the two paths.

POWER

December 12, 1911

Superheated Steam, Interesting Tests

Prof. Enibrey M. Hitchcock, at the re-
cent meeting of the Ohio Society of Me-
chanical, Electrical and Steam Engineers,'
presented a paper upon the above sub-
ject. It was based upon experiments
conducted as thesis work by Messrs.
Cochrane, Foster and Bate, at the labora-
tories of mechanical engineering at the
Ohio University, where Professor Hitch-
cock is engaged. The separately fired
Foster superheater upon which the ex-
periments were made has a capacity of
3500 pounds of steam per hour raised
to (302 degrees Fahrenheit at a pressure
of 125 pounds and a safe working pres-
sure of 108 pounds. The effective heat-
ing surface is 84.92 square feet, ex-
clusive of headers and manifolds. With
a grate of 6.33 square feet the ratio of
heating to grate surface is 13.4. The
rated capacity involves the transmission
of 5358 B.t.u. per hour per square foot
of internal heating surface, which is 58
per cent, greater than that of the aver-
age boiler-heating surface based upon
the evaporation of 3.5 pounds of water
per hour per horsepower from and at
212 degrees. The paper deals with three
tests, one on the pipe line to determine
the drop in pressure and temperature at
different rates of flow, one on the super-
heater itself, and the third on a McEwen
tandem-compound engine running con-
densing and using, first, saturated steam
and then steam from the superheater.

Pipe-line Tests

In conducting the pipe-line trials the
quantity of steam flowing through the
superheater line was made constant for
a sufficient length of time before the
trials to secure continuity of conditions.
In order to obtain the average external
temperature, and thus to reduce all losses
to the basis of B.t.u. per square foot per
degree of temperature difference, three
thermometers were suspended along and
about 3 feet directly under the header.
The total distance from the superheater
to the end of the header, or gage to
gage, is 121 feet, and the line contains
two tees and three elbows. The area of
the heating surface is based upon the
outside dimensions of the pipe line.
The surface of the header between the
points at which the temperatures were
taken is 61.3 square feet.

Immediately following the trials of the
uncovered line it was covered double
with 1 inch of fire felt and 1 inch of 85
per cent, magnesia. The results obtained
on the covered and uncovered pipes are
given in Table 1.

The results obtained for the uncovered-
pipe test check the general value usual-
ly taken for heat loss per B.t.u. per
hour per degree difference in temperature
for uncovered pipe — that is, 3 B.t.u. —

The paper deals with three
tests made with a separately
fired superheater at the Uni-
versity of Ohio: one to de-
termine the percentage of
the heat vahie of the fuel put
by the superheater into the
steam; one to determine the
loss of heat and of press-
tire in the steain main with
steam of different degrees of
s^lperheat and at different
rates of flow; and one to
compare the performance of
a compound high-speed con-
densing engine when sup-
plied with superheated steam
with that when saturated
steam, was used.

but at the same time there is shown a
drop in this loss with a drop in velocity
of the steam through the line. The re-
sults obtained with the line covered run
somewhat above the values usually given
for cases of covered line, and, with the
exception of the first trial of this set,
the results indicate a practically constant

outlet. For obtaining the drafts and the
temperature of the escaping gases Elli-
son inclined draft gages and a Hohmann
& Maurer mercurial pyrometer were
used. An Orsat apparatus with a con-
tinuous gas sampler and collector was
used for obtaining the composition of the
escaping gases. In order to have the
superheater in a well heated condition,
it was fired up at 1 a.m. of the day of
the trial and was run steadily until the
test began at 7:45 a.m.

The following are the general results
obtained:

General DniEN'sioxs of .Superheater

Number of elements 21

Diametsr tubes, internal, inches ... 1.8

Diameter tubes, external, inches. . . 2.0

Length of element 4 ft. 3.5 in.

Area heating surface inside, square

feet 84.92

Kind of furnace hand fired, shaking grate

Diraen.sion of grates, 3 feet 2 inches

by 2 feet 6 inches, square feet ... 6 . 33
Ratio of grate area to inside heating

surface 1 to 13.4

Area opening into flue, square feet. 2
Floor space, 9 feet 8 inches bj' 5 feet

4 inches, square feet 51.2

Conditions

Date of trial June 6, 1911

.State of weather Clear

Duration of trial, hours 10

Kind of fuel Pocahontas run-of-mine

A\-ERAGE PRESStTBES

Steam pressure by gage, entering

superheater, pounds 107.7

-Atmospheric pressure by barometer,

inches 29 . 25

Absolute steam pressure, pounds.. . 122. 1

Steam pressure by gage, leaving

superheater, pounds 100 . 2

Pressuhe.
Pounds

Tfjiperatuke,

P-iVHRENHEIT

1°

£:fe

is

= §■•=

3

H

K

P a

ail'

11

If!

g

3

s.

&

1

3

ris

3

1

■a
c

1
c

■a
1

e

o

c

SO.II
79 . .")
78. o
97 . 6
95 . 6
96.5
:24.9
124. U

76.3
77.0
77.0
94.2
95.0
95.4
121. S
123.0

388.0
422.0
513.0
402.5
445.5
550.0
424.0
.J04.0

361.4
375.5
399.1
371.7
389.5
404.1
391.4
423. S

335.0
336.0
334.5
346.0
345.5
343.0
362.1
369.5

86.9
83.3
84.1
86.2
77.4
81.3
S3. 2
83.4

3.7
2.5
1.5
3.4
0.6
1.1
3.1
1.0

53.0
86.0
78.5
56.5
100.0
107.0
61.9
134 5

26.4
39.5
64.6

44^0
61. 1
29 . 3
54 3

3,559
2.431
1,268
3.656
2,243
1,130
3,672
2.000

6,550
4,505
2,387
5,635
3,500
1,780
4,630
2,560

50,800
50,900
43,400
52,600
54.250
38,000
62,400
60.900

795

796
687
833
858
602
988
964

3.0s

2.96
2.43
3.06
2.96
2.06
3.36
3.07

1

>

79.1
77.5
97.3
98.3

77.6
77.3
94.4
94.9

343 . 5
354.3
350.2
350.1

342.8
343.7

348 , 2
348.0

334.6
335.0
344.0
342 . 5

S8.9
90.5

87.7
89.4

1.5
0.2
2.9
1.4

8.9
19.3
6.2
7.6

8.2
11.7
4.2

2.496
1.237
3.408
2,540

4,500
2,230
5,140
3,826

11,210
7,920
7.990
7.800

17S
126
127
123

0.713
0.503
0.493
0.483

loss under variable conditions. It will be
observed that the temperatures carried
in the line were such as to give a small
amount of superheat at the end of the
header.

Superheater Trial

In preparing for a test of the super-
heater a Barrus calorimeter and pres-
sure gage were connected to the supply
line close to the superheater, in addi-
tion to a pressure gage and a Hohmann
& Maurer standard thermometer at the

Steam pressure by gage, end of

hea<ler, pounds 95 . 0

Forci" of draft over lire, inch 0 036

Force of draft leaving superheater,

inch 0.091

Average TEjn>ER.\TtJBEe

Fire room, degrees Fahrenheit 90 2

Products of combustion leaving

superheater, degrees Fahrenheit. 580.3

Steam leaving superheater, degrees

Falirenheit 564 . S

Fuel

Kind of firing spreading

Thickness of fire, inches 4

Weight of coal fired during trial,

pounds 828

Weight of refuse, pounds 43

Per cent, refuse to coal 5. IS

December 12, 1911

POWER

889

Proximate analysis in per cent.

Moisture 0.96

Volatile matter 19.06

Fixed carbon 75 . 82

.\sh 4 . 16

fit imate analysis in per cent.

Carbon 87.35

Hvdrogen 4 . 26

Oxygen 2 .65

Nitrogen 0.86

Sulphur 0 . 72

Asb 4.16

.\n3lvsis refuse in per cent.

rombustible 22 . 0

.\sh 78.0

Calorific value of fuel by Mahler
calorimeter, B.t.u 14,9S6

QrALiTT OF Steam
.Moisture in steam entering super-
heater, per cent 1 . 00

Steajc

Weight of wet steam entering super-
heater, pounds 45,892

Weight of dry .steam entering super-
heater, pounds 45,433

Weight of water entering super-
heater, pounds 459

Steam per HotrR '

Weight of water evaporated and

superheated, pounds 45.9

Wetht of dry steam superheated.

pounds 4,543 .3

Economic Results
Water evaporated and superheated

per pound coal, pound 0 544

Steam superheated per pound coal,

poimds 54 . 866

B.t.u. taken up by water per pound

coal 549.3

B.t.u. taken up by steam per pound

coal 6,337.0

Total B.t.u. per pound of coil 6,886.3

Efficiency of superheater, per cent.. 45.95

Flue-gas Analysis

Carbon dioxide by volume 7.11

Ox.vgen 12.70

Carbon monoxide 0 00

.Vitrogen 80 19

Heat Balance per Pocsd of Coal

Per
B.t.u. Cent.

I/)SS due to latent heat 392 2 62

Ix>ss due to proflucts of corn-
bastion 1,470 9 82

lx)s- due to air excess 2,010 13 42

Ix)-- due to unburned coal 164 1 09

Ixiss due to radiation, etc 4,064 27.10

Heat used in superheating. . . . 6,886 45 9.5

Total heat supplied 14,986 100 00

At first glance, the efficiency obtained,
45.95 per cent., would seem low, but
when the size of the superheater and the
area of the fire door In relation to the
grate area are considered, the results
obtained are to be expected. The heat
taken up per hour per square foot of in-
ternal heating surface was 6714 B.t.u.,
or 25 per cent, in excess of the super-
heater rating. The maximum velocity of
the steam through the elements was 7000
feet per minute with a drop through the
superheater of 7.5 pounds and a drop
from the superheater to the end of the
header of 5.2 pounds, with an average
velocity in the line of 8500 feet per
minute.

Engine Trials

The McEwen engine is a horizontal
tandem-compound with an inertia gov-
ernor controlling the admission to the
high-pressure cylinder only. The load
was supplied by a brake. During the
superheat trials the temperature of the
steam was taken in the high-pressure
steam chest.

Ev'iixr, I)i\ir.s»"iovn

!>lftmetpr hlgh-prpwiure cylinder, inchw . w 2

I Mameter hiKli-pr«««urp rod. inches I 7.'t

Cloarancp hieh-preMure cylinder tfmii,

iK-r rent .. 1271

C1"aran<-e hieh-prfiwurp cylinder, crank

end. per cent 13 fl»

Diameter low-pressure cylinder, inches. . 13.24

Diameter low-pressure rod, inches 2.25

Clearance low-pressure cylinder bead end,

per cent 11.86

Cleiriiice low-pressure cylinder, crank

end, per cent > 11.23

Stroke, inches 12 .0

Results

Number of run

R.p.m. continuous
counter .

Pressureat throttle
by gage, pounds

Pressure in receiv-
er, pounds

Vacuum in ex-
haust line at en-
gine, inches. . . .

Moisture in ste^im
at throttle, per
cent

Temperoture
steam in steam
chest , degrees
Fahrenheit ....

Degrees superheat
in steam chest,
degrees Fahren-
heit

Weight of dry
steam per hour
from condenser,
pounds

I.h.p.. high-pres-
sure cylinder. . .

I. h.T>.. low-pressure
cylinder. .

I.h.p., total.

Dry sle.am pel
i.h.p.-h our,
pounds

Thermalefliciency
per cent

284
110
1.3

25.3

1.26

843
13.89

24.28
9.54

2

4

289

285

109.2

100.4

6.7

3.8

25.3

25

1.92

419.4

81.3

113

S5S

23.78

23.44

28.70
52.48

23.07
46.51

21.23

18.44

10.9!

12.15

The results obtained per pound of dry
steam per indicated horsepower per hour
on the two trials with saturated steam —
when referred to a water-rate curve for

indicated horsepower loads are 22.25 and
20.1 pounds as against 18.44 and 17.27
pounds, or an excess of steam for the
three-quarters load of saturated over
superheated of 20.6 per cent., and for
the full load 16.9 per cent.

An Assumed Case

Although the use of superheated steam
in this unit as well as others shows a
marked degree of reduction in the weight
of the steam used, this does not indicate
the fuel or net saving, as all losses and
additional fuel costs to produce the super-
heat are not considered.

Taking the case of an assumed plant
of such a capacity as to require a super-
heater of the size of the one under con-
sideration, and taking this plant into ac-
count with and without the superheater,
the difference in fuel consumption could
be computed as herewith shown.

This assumed plant is to have a nor-
mal capacity equal to that of the super-
heater when giving, say, 100 degrees
Fahrenheit superheat at 120 pounds gage
pressure. From the above superheater
test, considering the same efficiency as
obtained, this capacity would be 8890
pounds of steam per hour and on a basis
of 17.27 pounds of steam per indicated
horsepower-hour for the engine water
rate, would give an engine or engines of

Fir,. 1. Boiler Fiei -testing Laboratory of Ohio State University

this same engine obtained a short time
previous to these trials while running
under practically the same conditions
through a range of six loads var>'ing
from .Vt.5 to 77.."^ indicated horsepower —
exceed those results by about 0.1 pound
of steam per indicated horscpowcr-hour,
or a difference of 0.5 per cent. TTicrc-
forc. referring to this water-rate curve
for the loads carried on the superheat
trials, the rates for saturated and super-
heated steam for the 46,51 and 00.01

510 indicated horsepower. Consider the
line from the superheater to the engine
to be extra-heavy 3.5-inch pipe and 100
feet in length with double covering. The
velocity of the steam through this line
would be 8300 feet per minute, with a
loss in heat due to radiation, of 2 B.t.u.
per pound nf steam, or a drop in super-
heat of 3.(1 degrees Fahrenheit. The
drop in the pressure through the super-
heater would probably be 15 pounds with
a drop through the line of 5 pounds, or

890

POWER

December 12, 1911

a total drop of 20 pounds, giving a
pressure at the engine of 100 pounds.
Taking the efficiency of the superheater
practically the same as that obtained on
the test, or 45 per cent., and figuring on
a good grade of Hocking coal having
12,000 B.t.u. per pound, the coal required
per hour for superheat would be 105.5
pounds. Considering the boiler generat-
ing the steam and using the same coal,
and having an efficiency of 65 per cent.,
the coal required per hour by the boiler
with a gage pressure of 120 pounds and
a feed-water temperature of 200 degrees
Fahrenheit would be 1156 pounds, or a
total for the boiler and the superheater
of 1261.5 pounds.

Eliminating the superheater and con-
sidering the engine using saturated steam
only, the total steam required by the en-
gine would then be 10.251 pounds per
hour. Taking the usual saturated steam
velocity of 6000 feet per minute, the esti-
mated steam-line diameter would be 4.5
inches and in all probabilities in prac-
tice, a 5-inch lin^ would be installed.
This size line Would give a radiation loss
of 18,750 B.t.u. per hour, which would
be equivalent to the condensation in the
line of 21 pounds of steam per hour, thus
iraking the total dry steam required from
the boiler 10,272 pounds per hour. Con-
sider as before the boiler efficiency as
65 per cent, at a pressure of 105 pounds
and a feed-water temperature of 200 de-
grees Fahrenheit; the coal required per
hour would be 1343 pounds, an increase
of 81.5 pounds per hour, or 6.45 percent.,
which would stand for a saving for a
working year of 3000 hours of 122.2 tons.

In considering the financial aspect of
the problem the elements entering in are
the number of hours the plant is in op-
eration, th^ cost of fuel, additional op-
erating costs, if any, depreciation, etc.
These elements would vary with each

heater, partly on account of the mass of
cast iron surrounding the heating pipes,
is not sensitive to changes of conditions,
and it would take some time for the tem-
perature of the steaiTi to change when
the drafts and the rate of steam flow
were altered.

President Rabbe had had some e.xperi-
ence with superheaters in Stirling boil-
ers which gave trouble through variable
superheat. Conditions were improved,

A member said that the claim was
made that notwithstanding its higher
temperature, there was less loss by radia-
tion with superheated than with saturated
steam. He referred to recent researches
on superheated steam by Dr. Armand
Duchesne at Liege, where temperatures
were measured both with a silver-plati-
num thermocouple and with mercury
thermometers in the regular way. While
the steam was saturated the temperatures

Fic. 2. Babcock & WiLCO.x E.xperimental Boiler and Foster Superheater

through a better control of the feed
water. He said that one of the engi-
neers of a large electric company had
told him that they did not want more
than 100 degrees of superheat.

Professor Hitchcock said that the en-
gineer of a large plant using 170 pounds
and a little over 100 degrees of super-

«

TABLE 2

Steam. Pounds peb
i.h.p.-hoxjr

B.T.U. PER I.H.P -mS-UTE

R.iKKixE Efficiency,
Per Cent.

Improvement
in Rankine

Load,
l.h.p.

Saturated

Superhea'd

Saturated

Superheated

Saturated

Superhea'd

Superheating.
Per Cent.

34.73
46.51
.'52.48
60.01

24.28
22.25
21.23
20.10

is'44

17.27

439.57
406.40

382.17
367 . 13

336! ig

'328!22

37 19
42.9
44 9
47.5

49 .59
.53 . 5

6 69

6 on

individual plant, depending upon its loca-
tion, character of design and construc-
tion and its operation, so, therefore, the
advisability of using superheated steam
in any plant is a problem for the owner,
or the designing or operating engineer.
Discussion
Asked about the investment and main-
tenance, Professor Hitchcock said that
the cost of the superheater was $1000.
They set it up themselves. The attend-
ance would not amount to anything, as
but 825 pounds of coal were fired in 10
hours. Used with natural gas, it would
be ideal, pennitting an easy regulation
of the amount of superheat. The super-

heat had told him that if he were going
to build a new plant he would cut the
pressure down to 150 pounds and use
200 degrees of superheat.

Mr. Beebe, of the Fisher Regulator
Company, said that the Chicago North-
western Railway cut its steam pressure
from 210 to 170 and put in superheaters
with a saving of 4 tons of coal per trip.
Some of the engineers burned out the
superheaters by shutting off the steam
and letting the train drift into the sta-
tions.

Professor Hitchcock said that over 200
degrees of superheat were being used
on the Fort Wavne division.

indicated by the two methods were alike,
but as soon as superheating set in there
appeared a very material difference. The
mercury thermometer read low, evidently
because it was indicating the temperature
of the somewhat cooled film of steam
gas about its w-ell and not the tempera-
ture of the whole mass. This difficulty
of communicating the heat from the
gaseous superheated steam to the metal
of the pipe is the probable cause of the
lesser radiation if such exists; but Pro-
fessor Hitchcock's tests show fully as
much loss per degree difference of tem-
perature as the recorded tests with satu-
rated steam, and since the temperature
difference is greater. the radiation loss
must he increased instead of diminished.
Pounds of steam are not a fair basis of
comparison as between saturated- and
superheated-steam performances, because
the superheated steam contains more heat
per pound. He had computed the heat
consumption in B.t.u. and the Rankine
efficiencies — that is, the ratio of the heat
units required by an engine of 100 per
cent, efficiency working in a Rankine
cycle between the limits given and the
actual number of heat units required.
These are given in the accompanying
table and show the improvement in the
Rankine efficiency to be between 6 and 7
per cent.

December 12. 1911

POWER

-C^ "T^

-4-^^

Operation of Interpole Motors

By Gordon Fox

Interpole motors are now being exten-
sively used for variable-speed service,
for high-speed operation and to handle
A idely fluctuating loads, nearly all of the
.ommutation troubles previously devel-
oped by these classes of ser\'ice having
been eliminated by means of the interpole
construction. However, the auxiliary
poles add some complication to the or-
dinary shunt-wound machine and fre-
quently troubles arise from misunder-
standing of their exact functions. The
purpose of the intermediate poles is to
neutralize the effects of armature reac-
tion and self-induction and to maintain

some of it and increases the flux in the
left-hand part, near the poleface, pro-
ducing the same result as though the
field flux had been pushed over physically.
The actual neutral point on the arma-
ture is exactly midway between the cen-
tral part of the flux under one pole and
the corresponding point under the neigh-

tion between the no-load and full-load
neutral points, usually at the point where
commutation is best with that load which
is carried most of the time.

In a properly adjusted interpole motor
the neutral point remains fixed, regard-
less of the load. With the brushes prop-
erly set the motor should be reversible
and show the same speed characteristics
in both directions; this is a good criterion
as to the correctness of the brush posi-
tion. The polarity of the interpole is
the same as the polarity of the preceding
main pole. If the interpole is too strong
or if the brushes are given a backward
lead, the main field flux will be partially
neutralized and the result is much the
same as though the field had been weak-

FiG. 3.

a fixed electrical neutral point, allowing
the brushes to be set permanently at one
place and to effect practically sparkless
commutation at all loads. In an ordinary
shunt- or compound-wound motor, when
the load increases, the neutral point shifts
backward with respect to the direction of
rotation, by reason of the magnetic reac-
tion of the armature winding. A study
of Figs. I, 2 and 3 will help to make this
clear. Fig. 1 shows approximately how
the magnetic flux passes from a field-
I magnet "north" pole to the armature
' core when no current is flowing in the
armature winding. Fig. 2 indicates the
direction of the magnetic flux that would
be produced by current in the armature
winding alone. By comparing this with
Fig. 1 it will be evident that the armature
magnetism opposes the field magnetism
in the right-hand half of the magnet pole
and airgap and agrees with it in the other
half; the arrows A give the direction of
magnetic force due to the armature cur-
rent and the dotted arrows show the di-
rection of magnetic force due to the field
winding when it is excited. The result
is distonion of the field flux somewhat
as indicated in Fig. 3. The armature
magnetic force is too weak to neutralize
entirely the magnetic force in the right-
hand half of the pole, but if neutralizes

boring pole, when the flux is evenly dis-
tributed, as in Fig. 1. When the flux is
crowded more in one place than another,
as in Fig. 3, the central point is near the
densest part of the flux, as at C. Com-
paring Figs. 1 and 3 in this respect, it
will be found that in the latter the arma-
ture reaction has shifted the central point
of the flux back about I'j armature

A /^

FiG. 4. Interpole Flux Alone

teeth; the neutral point, therefore, will
also have been shifted backward to the
same extent, and brushes which were on
the neutral points of the commutator
when the flux was evenly distributed, as
in Fig. I, will be about I'J bars ahead
of the actual neutral points if the field
becomes distorted by armature reaction
as In Fig. 3. On an ordinary shpnt-
wound machine it is common practice to
set the brushes in an intermediate posi-

ened; the resultant commutating points
will be shifted away from the brushes
and the motor will probably race, because
of the reduced counter electromotive
force at the brushes. This will be caused
by excessive interpole magnetism only
with considerable load, because the in-
terpoles are magnetized by the armature
current and their strength depends on the

Fic. 5. Combined Fluxes

load. Fig. 4 shows the interpole flux alone
and comparison with Fig. 2 will show that
it is opposed to the magnetic forces of
the armature winding. Fig. .'> shows the
main and interpole fluxes combined.

From the foregoing it will be clear that
the inlcrpnlcs can affect the speed regu-
lation of a motor. When an interpole
motor drops off in speed from no load
to full load, it is probable that the inter-
poles are not sufficiently strong, whereas

892

POWER

December 12, 1911

if the speed increases with increasing
load the interpoles are too strong. When
properly adjusted an interpole motor
will run at nearly the same speed at all
loads. For this reason the term "regu-
lating pole" is sometimes used.

In most motors the interpole winding
is made with a few excess ampere-turns

exactly over this point of the commu-
tator. A load should then be put. on the
motor and the neutral point again deter-
mined. If this neutral point is beyond
the no-load neutral in the direction of
rotation, the interpole winding is too
strong; if behind the no-load neutral, the
winding is too weak. With the Interpole

Fic. 6. Commutator Potential "E.xplcrer"

and correct adjustment is obtained by
shunting the winding with german-silver
wire or ribbon.

An excellent method of testing the
brush setting and interpole strength is
by exploring for the neutral. Two pieces
of No. 6 insulated wire are soldered to
the ends of a piece of lamp cord, the

strength correctly adjusted the neutral
point will be in the same place at no
load and full load.

When a variable-speed interpole motor
is running with a weakened field it will
often be found that the commutating zone
is quite narrow; that is, the voltage be-
tween bars increases rapidly on each
side of the neutral point and a slight

sharp pencil. It is then again laid around
the commutator under the brushes, with
one end even with the edge of one brush
(see Fig. 9l; the remaining studs are
set so that the edges of the brushes will
"toe" the marks. The fiber washers which
insulate the studs often shrink somewhat
after heating and allow the brush studs
to become displaced.

When it is desired to reverse the di-
rection of rotation of an interpole motor,
either the shunt field winding or the
armature circuit, including the interpole
winding, may be reversed. Never re-
verse the armature without also revers-
ing the interpole winding. When either the
armature or the interpole winding alone
is reversed, the brushes spark and bum
under a load and the motor usually gives
out a decided hum; also, the speed drops
off very decidedly with an increase of
load.

Fig. 1 1 shows how the shunt field con-
nections of Fig. 10 should be reversed;

Fig. 7. Exploring the Commutator

free ends of the wires bared for about
an inch back and the wires taped to-
gether side by side, as illustrated in Fig.
6; the ends of the No. 6 wires should
be bent to such a distance apart that
they will just span two commutator seg-

brush shift will cause sparking or rac-
ing. In such cases it is particularly de-
sirable to have the brushes accurately
spaced. The easiest method of locating
the brushes is by means of a spacing
strip. A strip of heavy wrapping paper
about an inch wide is wrapped completely
around the commutator under the

the leads /, and /,• are merely ex-
changed where they connect with the ex-
ternal leads F and N. Fig. 12 shows
the armature connections of Fig. 10 re-
versed incorrectly, the armature itself
being reversed and the interpole winding
left unchanged. The correct way to re-
verse the armature circuit of Fig. 10 is

Fic. 10.

Fig. 11.

Fig. 12.

ments. The free ends of the lamp cord
are connected to a low-reading voltmeter.
The points are moved around the sur-
face of the commutator, as indicated in
Fig. 1, until a position is reached where
the voltmeter needle indicates exactly
zero, denoting no voltage between bars.
The neutral point should be thus deter-
mined at no load and the brushes set

brushes, allowing the ends to overlap,
as represented in Fig. 8, and a cut is
made across the overlapped ends along
a mica segment, so that the length of the
paper will be the exact circumference of
the commutator. The paper is then re-
moved and its length divided into as
many equal sections as there are brush
studs, and the divisions marked with a

to transfer the lead N, together with the
shunt lead /:, from the brush cable B to
the interpole terminal M and transfer
the lead P from the interpole terminal
to the brush cable B. This will reverse
the current through both the armature
and the interpole winding and keep the
direction through the shunt field wind-
ing unchanged.

December 12. 1911

POWER

893

LETTERS

Mr. Haw kins' Compressor
Motor

In the issue of October 31, J. C. Haw-
kins asks for advice concerning a spark-
ing commutator. With the information
given, it is difficult to decide just what
is the cause of his trouble; but it fre-
quently happens that owing to wear of
the bearings the center of the armature
is dropped somewhat so that the field in
which the armature works is not uni-
form. This results in the brushes not
working in the proper commutating lo-
cation, and it may be that this is the
cause of Mr. Hawkins' trouble. It also
happens that the field strength of the
various poles is not always uniform, and,
therefore, the brushes are not actually
located at the proper points of commuta-
tion. It might be worth while for Mr.
Hawkins to explore the potential about
his commutator, and see that his brushes
are located at the proper commutating
point. With brushes fixed on a yoke, as
they usually are, it might readily be that
some of the brushes are properly located
and the others not; this is frequently a
cause of very vicious sparking, resulting
in badly pitted or heated commutators,
which in the course of a very short time
results in the machine running very hot
and the commutator getting in a bad
condition. This trouble can usually be
located by the commutator being marked
pretty badly on certain definite bars, and
also being discolored on the same bars
to a greater extent than on any of the
others.

Henry D. Jackson.

Boston. Mass.

There may be several causes of Mr.
Hawkins' brush sparking. If the com-
pressor is the cause, it should be notice-
able by watching the spark. If the
brushes spark perceptibly more at each
compressing stroke than at other times,
this would indicate that the flywheel on
the compressor is not heavy enough. This
may also be detected by watching an
ammeter in the motor circuit; if the
needle swings badly it indicates the same
trouble, the average of the swing show-
ing whether a momentary overload is put
on the motor. I have seen the same
effect produced by reciprocating printing
presses, each reversal of the bed causing
a violent swinging of the ammeter needle.

Another possible cause is too high re-
sistance in the brushes. If after clean-
ing the commutator and brushes the
motor works all right for a few hours
and then begins to spark, with a general
blackening of the commutator bars. I
should say the brushes were of too high
resistance; a change to brushes of less
resistance should cure this trouble.

Sometimes the brushes cover too many
commutator segments and therefore

spark badly. When a commutator is new
the brushes may cover the right num-
ber of bars but as it is turned down the
bars narrow up, being wedge-shaped,
and the brushes overlap another segment
and cause sparking.

Brushes that have been in use for a
long time and have been heated and oil
soaked sometimes give trouble, which
new, clean brushes will cure.

In dressing a commutator I use No.
\'A sandpaper first, then No. 00 to fin-
ish, using oil on both kinds; the oil col-
lects the copper dust and prevents its
getting all over the generator or motor,
and it also gives a better finish. For
the final gloss I use a liquid polish on a
piece of waste, after sandpapering. This
gives a good smooth surface for the
brushes.

In offering the foregoing suggestions
I have assumed that the motor has no
grounds or other internal troubles.

Homer J. White.

Keene. N. H.

Changing a 220 A'olt Arma-
ture to 110 N'olts

We recently wished to put in an extra
shop motor but the only motor at hand
was a bipolar, 220-volt machine, and our
service voltage was 110. I therefore de-
cided to change the motor to 110 volts.
The field winding was easy; the two field-

Fic. 1. Original Commutator Con-
nections

magnet coils were simply connected in
parallel instead of in series.

The armature was a more tedious job.
In order to avoid rewinding the armature,
I had to reconnect the winding at the
commutator so as to put one-fourth of

Fir,. 2. Top Lfads All Lifted Out

the coils in series in each of four parallel
groups. First. I took the top wires nut of
three commutator lugs and tested to see
where the other end of the middle coil
was connected ; the test showed that the
bottom wire In one lug and the lop wire
in the next lug to the right were the ter-
minals of one coil, as indicated in Fig.
I. Then I unsoldered the top wires from
all of the lugs, leaving the bottom wires

undisturbed, as in Fig. 2. The top wire
from the lug a was moved over to lug b,
the top wire from h transferred to c, and
so on all around the commutator, as in-
dicated in Fig. 3. This put the coils A,
C, E, etc., in one group around the arma-
ture and the coils B, D, F, etc., in another

^ B C D E F 6

Fic. 3. Top Leads Moved Over One Bar

evenly distributed group, the two groups
being separate from each other and con-
nected symmetrically to alternate com-
mutator bars, as shown in Fig. 4. Then
I got brushes with faces wide enough to
cover three commutator bars, and set
these as usual; the wide faces connected
the two sets of coils in parallel, as shown.
In order, however, to insure stable paral-
lel connection between the two groups, I

Diagram of the Result

put "jumpers" from bar to bar of the two
sets of commutator bars; one from bar
<i to bar ^. one from <■ to d, one from c
to f. and so on all around.

This arrangement gave four paths in-
stead of two through the armature wind-
ing, each one containing half as many
coils as were in series before the change;
as the number of coils in scries was one-
half and the number In parallel twice as
great as originally, the armature voltage
was reduced one-half and the current-
carrying capacity doubled.

The change could not have been made
satisfactorily if the commutator had had
an odd number of bars, because the two
groups of coils would not have been
equal.

W. Russell Cooper.

Indianapolis. Ind.

The use of a log sheet forms a prac-
tical routine reminder of the engineer's
daily duties, and it keeps him on the
alert lo details of operation which might
otherwise fail of constant inspection.

POWER

December 12, 1911

Test of ail Oil Enj^ine*
By Forrest M. Tovt l

A test of a De La Vergne Type FH oil
engine was made at the pumping station
of the Standard Oil Coniipany, Fawn
Grove, Penn., on April 20 and 21, 1911.
The engine was an 85-horsepower ma-
chine with one cylinder 17x27 'i inches
and running at about 180 revolutions per
minute. This type of engine operates
on the well known four-stroke cycle,
but the fuel is injected into the cylinder
at the completion of the compression
stroke instead of being drawn in gradual-
ly, as in the gas engine.f

Before shipment the engine was tested
and developed a brake horsepower with
0.474 pound of Solar fuel oil per hour
when running at 65.11 brake horsepower,
and 0.462 pound when running at 85.74
brake horsepower.

In order to obtain as accurate data as
possible, not only of the engine but of
the combined pumping plant, it was de-
cided to make a second brake test at
Fawn Grove with the engine doing prac-
tically the same work as when pumping,
and to ascertain as accurately as possible
the ratio between the brake horsepower
and the pump horsepower.

In preparation for the test, a Govern-
ment-sealed platform scale, weighing to
single ounces, was procured for weighing
the oil. The water for cooling purposes
was taken by gravity from a tank and
allowed to waste, the amount used being
computed from measurements taken. The
inlet temperature was taken at the tank,
and the temperature of the water after
passing the jackets by placing a ther-
mometer in the line near the engine.

The amount pumped was ascertained
by gaging the tank at Fawn Grove, and
checked by gaging the tank into which
the oil was pumped. The pressure was
recorded by a Bristol recording gage and
also read on a special Ashcroft gage,
the latter, on the completion of the test,
being taken to New York and compared
with the standard gage of the company,
which is graduated from a mercury col-
umn, situated in the Standard Oil build-
ing, high enough to give direct readings
up to 875 pounds per square inch. The
temperatures were taken with standard-
ized thermometers, and the cards with a
Crosby indicator, which was returned to

' *Abstract of n paper read before the Amer-
ican Society of Mechanical Knglneers, De-
cember, 1911.

tThls engine was fiill.v flescrihed in I'nwKit
for Jannary 25, 1910.

the makers at the close of the test and
found to be correct.

The exhaust gases were tested on the
ground by using an Orsat apparatus.
Samples of the oil were tested for calorific
power. The average as obtained by one
observer was 19,059 and this figure was
used in working up the tests. Two tests
were made by another observer and re-
corded 18,920 and 19,300 B.t.u. Prof.
H. C. Sherman's formula, B.t.u. = 18,-
650 + 40 (Baume degrees — 10)* makes
this 19,570. This formula is roughly ap-
plicable to all the American crude oils.

/82 Rtv. per min.
6S lb. Mean Effective Pressure
98 Indicaied Horsepower

Fig. I. Representative Diagram

No analysis of the oil was made, but
for the purposes of chemical calcula-
tions it was assumed to be as follows,
by weight:

Carbon O.Sti

H.vdrogen OIL'

Other material 0 02

The accuracy of the method used in
analyzing the gases is not such as to
warrant going to the trouble of making
an analysis of the oil. By comparison
with available analyses the above is be-
lieved to be substantially correct.

Three tests were made: the first. A, a
full-load prony-brake test; the second, B,
a pumping test using the engine under
the actual operating conditions; and the
third, C, without disturbing any of the
engine adjustments but simply substitut-
ing the brake load for the pump load, so
that the oil consumption and speed were,
as nearly as possible, the same. By
comparing B and C it was thought that
the friction of the pump could be more

I

accurately ascertained than in any other
way. There was no auxiliary machinery
used, the cooling water being delivered
by gravity.

The duration of each test was 3 hours,
and the hours checked so closely that
it was considered unnecessary to con-
tinue the runs for a longer period.

The number of revolutions per hour
was obtained by using an Ashcroft
counter. During test B the counter was
on the pump and the revolutions were
computed in the ratio of the gearing;
during tests A and C the counter was
connected direct to the engine. The re-
sistance of the pump load, test B, was
so constant and the regulation of the
engine so good that the number of counts
recorded for each hour was the same.
The fuel consumed for the first hour was
31 pounds 2 ounces; the second, 31
pounds 3 ounces, and the third, 31
pounds. During the brake test C the
number of revolutions recorded was re-
spectively 10,918, 10,916 and 10,919. The
fuel consumption for the three hours was
31 pounds 6 ounces, 31 pounds 8 ounces
and 31 pounds 4 ounces.

The following chemical computation
was made in connection with test C,
and is based on the analysis previously
given, assuming that all of the oil was
burned.

Pounds per Hour
( iwseii for hvdrogen com-
bustion 30.12

Ox.vgen for carbon 71.95

Total oxj-gen 102.07

.\ir used for combustion. . . . 443. S

Excess air (16.i.2 per cent.) 733.2
Hydrogen burned 3.76.">

Carbon burned 26.9S3

1207 74S

For comparison with other pump tests
the duty per 1,000.000 B.t.u. is given.
This duty is, however, based on the heat
units in the oil and should therefore not
be compared with the heat units delivered
to a steam engine in the steam, as is
customary with a steam pumping engine,
but with the fuel burned under the boiler.

It may be interesting to compare this
duty with that obtained by Professor
Denton in his test of the Laketon pump-
ing engine,* as oil fuel was used during
that test. The fuel used at Laketon con-
tained, by Professor Sherman's formula,
19,770 B.t.u. The evaporation in test 5
was 16.64 pounds from and at 212 de-
grees. This makes the boiler efficiency
81.3 per cent. The engine performance

'Tranxactionn .\merican Society of Mechan-
ical Engineers. Volume 14, pages 1349 and

December 12, 1911

P O \V E R

895

REsn.TS OF TESTS

Test

Start

End

Average revolutions per miiuitr
Average m.e.p..* lb. per sq.in. -

Average i.h.n,*

Average brake horsepower

Pressure pumped against lb. per s().in
Average gage nairels per hour

Pump h.p. by pi.ston displacement

Pump ho. b.v actual gage bbl. pumped. .

9:00 a.m.
12:00 m.
1S1.52S
S6.14
123.14
S.T.86

B

C

:00p.m

9:00 a.m.

:00 p.m.

12:00 m.

182.. i

181.96

65.6

65.85

94.2

93.36

64.57t

64 6S

.i70.00

256.38

60.143

.i4 48

FCEI. CONSVSIPTIOX

Test

I.b. of fuel per hr

l-b. of fuel per i.h.p.-hr

I.b. of fuel per b.h.p.-hr

Lb. of fuel per pump h.p.-hr. b.v displacement
I.b. of fuel per pump h.p.-hr. by gage barrel -

.Iackkt \V.\ter
Capacit.v of tank 39. 429 gallons per inch depth

Heat Balanck-

Tesl

Input. B.t.u. per hour

Engine useful work: B.t.u. per hour

Per cent

IjOss in cooling n-ater: B.t.u. per hour

Per cent

I<093 in exhaust: B.t.u. p<-r hour

Per cent

Ijosa in friction and radiation by rtilTerencc:

B.t.u. per hour

Per cent

H.t.u. per hr. in cylinder work

B.t.u. per hr. in useful pump work, output of sta-
tion

B.t.u., input per b.h.p.-hr

B.t.u. input per pump h p.-hr

Dutv, ft.-lh. per l.f»f>0.(HK) B.t.u

fba^ed on oil pumped i>er actual gage'

Efficiencib*

I.I rmirATioN

Tent

Cylinder oil

Engine oil:

I.b. t"''' hr

Ui. tier UMI lib p.-hr
IJ). per hr .
IJ>. per KKI b h p hr

31.375
0.333
0.485

Test

Temperature of gases, Fahrenheit

.4

678

483

C
485

Average anal.vses:

CO,, per cent .

O. per cent

N, per cent

lO^lf
82.06

5. 37
13 5
81.13

5.44
13.24
81.32

0.2387

Amount of gases, pounds per hour:

Bv calculation of displacement at 70 deg. Fahr.

If temperature were same as jacket water

From chemical test

1455.00
1181 on

l.iOO.OO

1491.00
1220.00

12ns (HI

Ti^t

.4

r

Inches used from lank - -

18

liu

Total gallons used

709.7

490 4

.Average pounds per hr

1971.0

1362.(1

.\verage pounds per b.h.p.-hr .

22.97

21.05

.■\verage mlet temperature, I-ahr

68,7

71.3

Average outlet temperature

193.3

1

187.8

,1.53

.592,813

.>97,976

,514

164.331

164,610

26.8

27.75

27 52

375

1.58,673

30.2

26 5
I19..520

20 03

1.55.173

25 95

.391

239,730
151,376

240.046

491

9,186t
9,987
198.66 i.lNm

9.244

Tn.1 . .

.4

»

r

Indicated heal I'lT . per cent

.38.4

40.45

40.2

Mechanical emciency

69.71

68 .55:

68, 55

Brake heal efficiency

26 8

27.-5

27 . 52

I'nmp:

Volumetric efficiency , per cent.
Pump and lnin«mi*-<ion, per cent

92 1

B

(I ««75
I 0625

Fi r.i. Oil. (IlllnoLi ('rude OH)

f\mimt. .13 de«f. - speciftr eravily

yU'h [mint. 35 deg. Fahr ; burning point ■ . . •. , '

Heat value. 19.059 B t.u per lb bv test: 19..57n bySherm»n'« fonnula

•Probably high, due lo Ihe momentum of Indtralnr psrt.4 Thi« arrnunts for comp«rali
low mechanical efficiency shown in the efllriency table
tC^mputed.
;A'Mume<l same a.» in le>t C.

was 124,375,834 foot-pounds per 1,000,-
000 B.t.u., or 15.985 per cent., and the
total efficiency of the plant was 13 per
cent., as against 25.52 per cent, for the
plant, which was the subject of the pres-
ent tests.

Fig. I shows a typical indicator dia-
gram for tests B and C. The compres-
sion pressure was 347 pounds per square
inch. The average drop in speed from no
load to full load was 4 revolutions per
minute, the speed range being 182 to 186
revolutions per minute. The other prin-
cipal results of the tests are given in
the accompanying tables.

Clean Blast P\irnace Gas

The gas-cleansing plant at the Central
Furnaces of the American Steel and Wire
Company appears to be particularly effi-
cient We are informed that gas con-
taining I'.i grains of flue dust at the en-
trance to the "clean gas" washer is de-
livered to the engines with only 0.0185
of a grain per cubic foot. The gas passes
first through the usual dust-catcher, then
through the "clean gas" washer, a wet
scrubber of tower form in which it is
given a whirling motion, then succes-
sively through a baffle washer, a Zschocke
washer and a Theisen washer. The fol-
lowing are representative analyses "be-
fore and after":

Haw Gas Engine Gas

«> . 26.3 26 4

H. 2.7 29

<H. 0 22 0.22

<'0, 12 9 13 0

N S7.S2 57.08

0 0.36 0.40

100 00 100.00

n.i.u. per cub.c foot (;;^.";pjV'^: 'm s

Grams inmslure per cubic fool 0.528

CORRESPONDENCE

Mr. Rice's Producer Plant

A. A. Rice, discussing in the October
31 issue the coal consumption of his
producer-gas plant, states that his fuel
( buckwheat 1 is of very poor quality. In
forming an estimate of what a plant
should do. the quality of the coal goes
a long way; if the heat units are not in
the coal you cannot possibly get them out
of the gas and must consume more fuel
than with a coal of a higher heat value.
It is sometimes true, however, ihat the
coal which is the highest in B.l.u. does
not work the best in a gas producer;
I have seen a poor coal give good work-
ing results inside the producer.

The coal consumption depends a great
deal also on the load on the engines; 1
have found lhat an increase from three-
quarters to full load has very little ef-
fect on the coal consumption.

I should estimate that Mr. Rice's plant
ought to consume on the average about
1200 to 1500 pounds per day, standby
losses included.

Mr. Rice otates that there is a little

POWER

December 12. 1911

leakage around the engine piston; this
is generally the case with large hori-
zontal gas engines, as there is a high
pressure in the cylinder immediately
after ignition. If the rings are not worn
too much, giving the piston and rings a
good dose of kerosene when standing
after a run helps the rings quite a lot;
it relieves them from stickiness by cut-
ting out any carbon and dirt that may
be in the grooves and also keeps the
combustion chamber free from carbon
deposit, especially on the bottom of the
cylinder, where it has the habit of form-
ing at the end' of the piston's travel.

On starting up after the standby over
Sunday I always give the pistons a dose
of kerosene and oil and when the com-
pressed air is turned on the engines turn
over as freely as if starting up just after
completing a run.

I should not think that speeding the
engines up would give a lower coal con-
sumption; they should be run at the
speed that they were designed for by the
maker.

As to the temperature of the gas, I
should say that if it is cool* when leav-
ing the scrubber it would be all right.
If the gas is not properly cooled,
vapor will condense in the gas pip-
ing and if the line is not fitted
with a trap or drain the accumulation of
water will cause trouble. Moreover, a
greater weight of gas will be taken into
the cylinder if it is cold.

Sometimes there is much difficulty in
getting the gas cooled, no matter how
much water goes through the scrubber.
This is generally the fault of the gen-
erator. If it becomes badly clinkered
around the sides, reducing the active
area of the fuel bed, the increased
intensity of draft will raise the fire level
above the proper combustion zone, re-
ducing the body of coal available to ab-
sorb heat and increasing the gas tem-
perature. In some extreme cases, air
from the ashpit will pass up around the
clinker without passing through the fire,
and mix with the gas above the fuel bed
and cause it to ignite there. There will
be great difficulty in cooling the result-
ing mixture of fresh and partially burnt
gases, and, of course, the engine will
not pull its load if the load is near the
producer's limit.

S. G. Rose.

Brockville, Ont.

In his letter of October 31, Mr. Rice
does not say whether his producer is of
the suction or the pressure type; this
would have some bearing on the fuel
consumption. The generator driven by
the 100-horsepower engine probably has
an efficiency of about 88 per cent, at the
rate of working (50 kilowatts average
loadK which would mean a brake load
of about 76 horsepower on the engine,

•Any tpmperatiii'o within SO dosifc* d'-l
of llic" atmosphere may bo considered "cool."
• — EniTOU.

or practically three-quarters of its rac-
ing. With such a load factor I should
say that with good coal a consumption
of 2 pounds per brake horsepower-hour
would be about right, with 100 pounds
extra for keeping the fire over night and
another 100 pounds for Sunday.

I am judging from results obtained in
our own plant. We have two 250-horse-
power pressure producers, two 125-
horsepower and one 160-horsepower en-
gines, direct-connected to electric gen-
erators. Steam is supplied by two small
boilers for the producer generators. The
load factor on the electric generators is
60 to 70 per cent. The plant runs 24
hours a day. 10 months of the year. The
producer fuel is anthracite pea and the
average consumption is 2.4 to 2.7 pounds
of pea coal and 0.3 to 0.4 pound of soft
coal (under the boilers) per kilowatt-
hour.

J. H. Lenoir.

Keene, N. H.

Timing the Ignition

The following method of timing the
ignition of gas engines and checking up
the time of ignition at frequent intervals
will be found both convenient and suffi-
cient.

Make a tram of such length that when
one end rests on the floor the other end
will be exactly opposite the center of the
crank shaft (see Fig. 1). Put the en-
gine on the inner dead center and set the
tram at the rim of the flywheel; make a
center-punch mark in the rim opposite
the end of the tram, so that it will be
the same distance from the floor that the
center of the crank shaft is. It is well
to make a punch mark also in the floor
at the point where the tram is set, for
future checking.

Measure from the mark on the wheel,
around the rim in the direction the wheel
is to run, the distance ahead of the cen-
ter that the engine is to fire and make
another punch mark at this point. The
igniter should trip when the flywheel is
in such a position that one end of the
tram will coincide with this point when
the other end is on the mark on the
floor.

The distance by which an engine
should fire ahead of the dead center is
usually stated in degrees. To find the
corresponding distance in inches it is
only necessary to multiply the number
of degrees by the circumference of the
wheel in inches and divide the product
by 360.

For example, suppose the flywheel is
10 feet in diameter and the engine is to
fire 20 degrees ahead of the dead
center. The circumference of the flywheel
is 10 X 3.1416 X 12 = 377 inches.
Multiplying this by 20 (degrees) and
dividing by 360 gives 20.94 inches for
the distance between the dead-center
mark on the flywheel and the mark that

should be opposite the tram at the in-
stant of tripping.

If the engine works on the four-stroke
cycle, care must be taken to see that

Fic. 1. Proper Hight of Tram

ignition occurs on the proper stroke; that
is, near the end of the compression
stroke.

Earl Pagett.
Coffeyville. Kan.

Sulphur in Gases

I was very much interested in reading
in the November 14 issue the article by
Olaf Olafsen on the effects of sulphur
in fuel oil or gas, and wish to add slightly
to his comments. He calls attention to
the effects of water in the engine in con-
nection with the sulphur, which may be
in either the oil or gas, this water turn-
ing the sulphurous anhydride into sul-
phuric acid, which acts very vigorously
on all parts of the engine with which it
comes in contact. He does not, however,
refer to the difficulties which are often
encountered in the exhaust passages and
pipes, particularly those of the outboard
exhaust.

It is not infrequent to find that the
exhaust of an oil or a gas engine is noisy
and very troublesome to the people in the
immediate vicinity of the plant; and in
order to avoid this noise, water is some-
times injected into the gases for the pur-
pose of cooling them more rapidly and
thereby reducing the pressure and noise.
Under these conditions also, the sulphur
in the gas or oil helps to form sulphuric
acid, and unless particular attention is
paid to the material of which the ex-
haust pipes is made, they are very
quickly eaten out. Various schemes have
been tried to avoid this difficulty, among
them being the use of earthen pipes and
also the delivery of the exhaust directly
into a pit filled with large stones, thereby
doing away with the use of water. My
particular reason for writing is to call
attention to the advisability of avoiding
the use of metallic exhaust pipes in
case water is used for cooling the gases,
or if water is used and the gas happens
to contain sulphur.

Henry D. Jackson.

Boston, Mass.

December 12, 1911

P O W E R

897

Cooling Public Buildings

By Fred Ophuls

In the November 28 issue of Power
an article by E. F. Tweedy gives a cor-
rect account of the present state of the
art of refrigeration as applied to the
cooling of public buildings and concludes
• with some calculations, the final results
of which give the refrigerating effect re-
quired to cool a theater or lecture room
100 feet square and 30 feet high to 75
degrees Fahrenheit, when it is occupied
by an audience of 500 people, the humid-
ity of the air not to exceed 60 per cent,
at this temperature and the circulation of
the air to be at the rate of five com-
plete changes per hour to afford the
proper purity for healthy living. The
maximum temperature in the shade was
assumed to be 90 degrees Fahrenheit and
the relative humidity 80 per cent.

To fulfil these requirements refrigera-
tion at the rate of 246 tons per hour was
found to be necessary. No figures are
given showing what such an installation
would cost or what the operating ex-
penses would be.

The artificial cooling of buildings of
this character is at all times of great
interest and many schemes have been
devised and patented and some apparatus
installed in hotels and public buildings
for this purpose. The water principally
used in these plants to cool and purify
the air is secured either from wells on
the premises or from the city supply.
While the best of these apparatus secure
at times quite a reduction in the tem-
perature of the air — and, of course, clean
it of most of the solid matter in suspen-
sion and the gases soluble in it — the
great drawback of these plants is the
excessive humidity at times of the air
so treated, which either produces a sen-
sation of cold or oppressive heat on ac-
count of insufficient evaporation of mois-
ture from the body.

These facts led to the use of refrigerat-
ing machines to cool and dry the air at
the same time. The results of plants of
this kind have not been as satisfactory
as could be desired on account of the
excessive first cost of the installation,
the high operating expenses and the ex-
treme temperature reductions sought. If
a 200.ton refrigerating machine or its
equivalent must be used to properly cool
an auditorium holding only 500 people,
the installation of such a system can-
not be considered. Furthermore, it has
been found that a reduction of from 15
to 20 degrees in the temperature n! a

room in summer will be very unpleasant
to those staying in it for any length of
time, as the body becomes rapidly chilled.
It seems therefore that this problem must
be taken hold of in a somewhat different
manner.

People in extremely hot climates,
where the temperature is 100 or even 1 10
degrees in the shade, do not suffer as
much from the effects of heat when the
atmosphere is ver\' dr\- as people do in
New York and other cities similarly lo-
cated when the thermometer registers
only 90 degrees in the shade and the
relative humidity is high. The conclu-
sion derived from these facts is that the
relative humidity of the air plays an im-
portant part in this problem and if it is
maintained at the proper point an actual
reduction of temperature may not be
necessary.

Investigations should be made to de-
termine for each degree of temperature
the relative humidity necessary for the
most comfortable living.

Experiments on these lines are being
made by the municipal departments of
some of the cities which have charge of
the public schools. The ultimate solu-
tion of the proper ventilating and humidi-
fying of the air in all public places will
most likely be found in the installa-
tion of a combined air-purifying and dry-
ing plant using water for purifying and
some cooling and mechanical refrigera-
tion for drying the air. It is also inter-
esting to determine whether, by the use
of mechanical refrigeration alone, a sys-
tem can be devised that will produce the
desired results at reasonable first cost
and operating expenses. It is the pur-
pose of this article to present some cal-
culations based on such a system, as-
suming that the main object is to reduce
the relative humidity of the air to the
proper point.

Instead of cooling the air to a point
so that the resulting temperature in the
auditorium will be 75 degrees Fahrenheit,
assume that for comfortable living the
moisture in the air should not exceed
t 1.^7 grains per cubic foot and that the

air entering with this content of moisture
need not be more than 5 degrees Fahren-
heit lower in temperature than the outer
air in the shade. The quantity of air
to be circulated is governed by the maxi-
mum weight of carbon dioxide which the
air is allowed to contain when discharged
from the building. For these calculations
assume that the air leaving should not
contain more than 0.105 per cent, of car-
bon dioxide, the initial contents being
0.06 per cent. The most adverse at-
mospheric conditions, in the locality of
New York, are a temperature of about
90 degrees in the shade and 8.874 grains
of moisture per cubic foot of air. The
auditorium is to be used for theatrical
or other similar purposes twice a day,
each session lasting three hours, allow-
ance to be made for rehearsals, cleaning,
etc.

An adult peVson exhales on an aver-
age 0.11 pound of carbon dioxide per
hour — this will be 55 pounds for 500
people. Each 100 pounds of air can
take up 0.045 pound of carbon dioxide
before it contains 0.105 pound and there-
fore 122.000 pounds of air must be sup-
plied per hour for 500 persons.

To reduce the moisture contents of the
air from 8.874 to 4.437 grains the air
must be cooled to about 53 degrees Fah-
renehit. The required refrigerating ef-
fect is figured as follows:

Itt.ll. piT

hour
Cnnili nsini; niiil rnolinc 11^2 pounds

of molBtiin- 1.24."i.2iiO

liodiK'inir Hie nir from 00 to .IS d<»-

Brce-s t'^nhrrnliplt 1.0-4.:t3:;

•loi.ii •.•..■!in..-.:f.'

By the use of an interchanger, the re-
frigerated air leaving the cooler at 53
degrees can be heated by the entering
fresh air to 85 degrees so that the net
refrigerating effect required is 1,390,000
B.t.u. per hour.

Figuring further that, during rehear-
sals and when cleaning, at least 30 per-
sons are busy in the auditorium, and that
the refrigerating plant is so constructed
that it can operate at maximum capacity
continuously and store up the refrigerat-
ing effect during the time when little or
none is required, the total refrigerating
effect under these conditions will be 14,-
687.400 B.t.u. per 24 hours, which is
equivalent to H) tons of ice-melting capa-
city per 24 hours. Allowing 10 per cent,
for heat leakage and other losses gives
a total of ."^5 tons of actual refrigeration
required per 24 hours.

A .'^5-tnn refrigerating system with
motor drive, condensers, cooling plant.

POWER

December 12, 1911

pumps, blowers, interchanger, air ducts
and all piping and connections will cost
approximately $12,000, and the operating
expenses per day of 24 hours, above
those of running the power plant of the
house and when operating at average
capacity, will not be over S36 per day.
The charges for depreciation, interest on
investment, taxes and insurance will be
$1800 per year. Basing the per capita
charge for these expenses on an average
of 50 per cent, of the total seating capa-
city of the auditorium and that the re-
frigerating plant will be operated 120
days per year, the total expense will
be $6120 per year or about 4 cents per
person.

The total cost of operating such plants
naturally decreases with an increase in
the seating capacity of the house as well
as with an increase in the number and
length of the performances per day.

Taking, for example, a motion-picture
or continuous-performance theater, seat-
ing about 1000 persons, in which are
given each day six sessions of two hours
each, the operating expenses, including
all fixed charges, would not exceed 2.3
cents per capita, based on the attendance
during the four summer months only,
and 1.67 cents per capita, for the attend-
ance of the whole year.

Russians to Adopt American

Railroad Refrigerating

System

To investigate the system employed for
the precooling and icing of perishable
products by American railroads, and to
gather data on the types of refrigerating
cars now in use in this country, repre-
sentatives of the private railroads of Rus-
sia were at San Bernardino, Cal.. inspect-
ing the precooling methods of the Santa
Fe Railroad Company. The party con-
sisted of Constantin Tihotsky, manager of
the transportation committee of St.
Petersburg; Oscar Dreier, traffic manager
of the Riasano Ooralsk Railway, in
southern Russia, and M. Krassovsky as-
sistant general superintendent of motive
power of the Moscow-Kazan Railway.

Congress of Refrigeration
Industries

The third international Congress of
Refrigerating Industries will be held at
Chicago, 1913. It will be divided into
sections for the discussion of the vari-
ous branches dealing with the technical
features of refrigeration, food products,
legislation, precooling and transportation,
and other sections of the work.

The first congress was held at Paris,
in 1908, under the auspices of the French
government; the second, in 1910, at
Vienna, with the support of the Austrian
government, at which time President Taft
extended the invitation to hold the third

meeting in America. Engineers and gov-
ernment officials from all parts of the
world interested in the industry will at-
tend.

Appointment is announced of G. Harold
Powell, of Los Angeles, Cal., for several
years in charge of investigations of cold-
storage and refrigerating transportation
of the Department of .'\griculture, as first
vice-president of the third congress. The
active president has not yet been an-
nounced. Secretary of Agriculture Wilson
is honorary president of the congress.

LETTERS

Homemade Outfit to Make
Calcium Chloride Brine

To begin with, two coal-oil, or regular
oil. barrels, of which one is sawed in
half to make two tubs, are cleaned with
boiling water, containing soda, until freed
from oil. The accompanying figure

out of black iron. With a hatchet, cui
the top and bottom of the cylinder and
break up the contents with a sledge.
Then fill the barrel and tubs with the
pieces and turn on the water. When
enough water has flowed into the barrel,
shut off the supply and turn on the brine.

The same arrangement may be used
for making salty brine with the excep-
tion that the salt is put in the barrel only.
William L. Keil.

Philadelphia, Penn.

Temperature of Ammonia
Discharge Pipe

I noticed that in a recent issue, T. L. D.
asked if the discharge pipe of his am-
monia compressor was too hot when it
would boil water dripped upon it. The
answer was made that under a working
pressure of 185 pounds, 250 degrees
Fahrenheit was not too hot for continuous
operation.

It would seem to me that it depends
almost altogether on the kind of com-
pressor being used, whether it is a dry-
or wet-gas machine and on the quantity
and temperature of the condensing water
available. For a dry-gas machine work-
ing under a head pressure of 185 pounds,
250 degrees Fahrenheit is about right.
But I believe most of the wet-gas ma-
chine builders, and especially the Fred
W. Wolf Company, recommend from 90
to 100 degrees for the discharge pipe
working under a head pressure of 150
to 180 pounds. I also believe that when
ammonia gas is heated beyond 100 de-
grees Fahrenheit that it will disintegrate;
at least this has been my experience, and
I have operated both kinds of machines.
I would be pleased to hear from other
operating engineers on this subject.

D. E. Aden.

Wilburton, Okla.

Caicium Chloride Brine Outfit

shows the cover, of a brine tank. One
section has been taken off and laid
lengthwise of the tank; on either side of
this cover the ammonia coils in the tank
can be seen. On the sides of both tubs
near the bottoms, holes are bored for
1 ■4-inch nipples, and the tubs are then
set on the ammonia coils. In the bar-
rel near the upper end, two holes are
bored diametrically opposite for two 1-
inch nipples. Near the bottom of the
barrel another hole is made large enough
for a P I -inch nipple. The barrel is
then set on top of the section of the
covers which lies across the opening of
the tank. The barrel and tubs are then
connected and a water and brine pipe
connection made with the nipple near
the bottom of the barrel.

Calcium chloride generally comes in
one solid lump in large cylinders made

Repairs to an Ice Plant

.About two months ago I took charge
of a 25-ton ice plant which was in op-
eration but was not turning out any ice.
Th_ compressor was working one-sided
so I took out the piston and found one
ring broken and a part of the bottom of
the piston broken off and lying in the
bottom of the cylinder. This had caused
the piston to work loose on the rod and
gave it movement enough to slip up and
hold the suction valve open when it
should have been closed for compression.
Consequently, the ammonia gas blew
back into the suction side, causing the
suction pipe to get nearly as hot as the
discharge pipe. .After putting in a new
piston rod and a new ring on the piston,
the compressor worked as well as a
new one.

Walter Carr.

Carmi. 111.

December 12, 1911

POWER

Issued Weekly by the

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flltrri.ATWX ^TATEUEyT
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Contents y„.,y

Power Plant of the .Vy. r Mill ^7l•.

Stipipl of Itnihester Mud Iinim V.\-

pIoHlon .s-^2

Erectlnc a l.iirce KnKlni' Flywheel ss4

lOnfftneers' Wiijies in China s>.-.

ItrltlMh-Canndlnn Power Company ssn

Snperheiitfd Sleam, Inli-reslin!.' Tests... .ss.s

Operation of lntei-)i-ile .Mi>tnrs s;i1

Sir. Ifawklnx' Com|ire«..or Miitm- S!i:;

Chnnuln'-' :i ".'L'n Yoli Armnlure to 11"

Volt.. .S!i;!

'I"nl of an (III Enaln.' vp4

t*leiin Illaflt Knrnnri* Has. s;i.-,

Mr. lllcP!i Prodmer Plant s".".

TImInc Hie linililon siKi

Sulphur in i;tim-i> x!Mt

c.K.llni{ I'ul.llc HiillillnE" H!i7

ConKrPKM (»f Itefrlgerntlon lncln«lrlp«. . . . HUH
llomemnde (lullii to Make C.ilelnm Chlor-
ide ttrln. H<iH

TemiKTflluri- of Amm'inin IMnchnrge PIim- H!tH

Ilepnlra lo nn lee Pl«nt H!l<<

i;<lltorl«l. HO'iltfHi

Pmillrnl I.pllern:

Pndprfe<-d Ktnltlnf v« OverlmrnlnK
....Took linrfu from lh<- lpl»ke...,
Pontroll'-r for Water Tank. . . Hump
(■•nu«e(l I'nund . Kno<klnir In .Mr
rompre««or« . .. Hot Wmer Suppiv
. , . .Repnlrlnc Slufflnt' Box i;lnnd
... The SufK-rlnlendenl Knew
Enirlne lloom Crane 001 OOS

Dlnetisiilnn I.elteri<:

AppBTAlU" for r>l>tminB Wfller...
Central Hiallon Hnleo Melho<lii ....
K.nglneern' Wflee" ... I.00W Trsnk
Pin.. .Value of CO. KernHler. . . .
rrllnrter Oil Tentefl for Aeliinl
Service .... The f,nooe l>(lf Book
i,„i,i, oni-Onfl

Safet)^ Appliances

Whether the pressure carried be high
or low as the terms are understood,
it would not be considered good prac-
tice to operate a steam boiler without a
safety valve, nor would such operation
be permitted in many parts of the coun-
try.

Safety valves are used to prevent the
rise of pressure in boilers above a pre-
determined point, by opening when that
point is reached and allowing the escape
of the steam, which, if retained in the
boiler, would cause a rise in pressure
above the point desired and perhaps dan-
gerously stress the material of the boiler
if it did not cause an explosion.

There is always a steam gage used in
connection with the safety valve, each
serving to check the other, and when
any marked difference appears both
should be tested and the discrepancy
corrected.

No level-headed business man nor any
intelligent engineer would contemplate
running a boiler continuously with only
a safety valve or a steam gage. Both
would be used.

When it comes to the other apparatus
in the plant, a different attitude is some-
times assumed. Steam-engine governors
are used for the double purpose of keep-
ing the engine running with a reasonable
regularity of speed while carrying a load,
and preventing an undue rise in this
speed if for any cause the load is re-
moved.

It often happens, however, that, through
misunderstanding some of the functions
of a steam-engine governor, the attendant
makes alterations which throw it nut of
adjustment and make it so nearly inop-
erative for certain conditions as to be.
instead of a governor, an element of dan-
ger.

Almost daily reports of flywheel acci-
dents show that there is need that in con-
nection with the ordinary steam-engine
governor there should be applied a
speed-limiting device which would shut

off the steam supply whenever the speed
of the engine exceeded a predetermined
number of revolutions per minute.

Boilers furnished with safety valves
and steam gages sometimes fail, but
the number of failures would probably
be much greater were either omitted from
the equipment. So, too, an engine pro-
tected against excessive speed by an in-
dependent speed-limit safety stop might
under some possible conditions run away,
but the probability would be so greatly
reduced that flywheel explosions would
be almost eliminated from the list of
industrial accidents.

As the safety valve and the steam
gage are, for obvious reasons, both used
on a boiler where either might possibly
be made to serve the purpose without
the other, so it would seem that even
mediocre business judgment would dic-
tate the use of a speed limit and safety
stop in conjunction with the steam-engine
governor.

Water Vapor in Air

Ordinary atmospheric air always has
mixed with it some water vapor, which
may vary from a very little in cool, dry
weather to a much greater quantity in
warm and damp weather. For sanitary
reasons, as in heating and ventilation and
for many industrial purposes, the meas-
urement of this vapor content and its
artificial regulation are matters of im-
portance to engineers.

In general, the quantitative composi-
tion of a mixture of gases can be found
only by chemical analysis. Bui when
one component is a slightly superheated
vapor, easily lowered to its temperature
of saturation or nf incipient liquefaction,
a simple phvsical dctennination of its
an-ount is possible. At saturation, char-
acteristic pressure and specific volume
are both fixed by temperature alone.
Further, a given space will contain the
same weight of vapor whether this exists
by itself, with its own pressure only, or
whether it is diffused through a larger

900

mass of gas, under the higher combined
pressure due to vapor plus gas. If the
"air" in a unit of volume is partly vapor
of water, there will be fewer oxygen
and nitrogen molecules than if no steam
molecules were present.

Air carries its maximum content of
vapor when the latter is in the state of
:saturated steam, ready to begin to con-
dense on the least abstraction of heat;
and the air itself is then said to be satu-
rated with vapor. If less vapor is pres-
ent, it may be considered as having been
superheated from some lower tempera-
ture of saturation, under the pressure
belonging to that temperature. Since
vapor tension or saturation pressure
rises with temperature, so does also the
weight of vapor which a given weight
of pure air can carry.

On these principles of thermal physics
are based two methods of vapor deter-
mination. By slowly cooling a polished-
metal surface and observing the tempera-
ture at which it just begins to be clouded
with condensed vapor, the dew point or
temperature of saturation for the actual
atmosphere is found. The weight of a
cubic foot of saturated steam at this
temperature measures absolute vapor
content or humidity, to be compared with
the possible content at the higher preva-
lent temperature in order to get relative
humidity.

Again, when water and nonsaturated
air are in contact, vapor tends to be
formed until the air becomes saturated.
Vaporization absorbs heat, which may
come from several sources, as from the
air or water or from the surrounding
bodies. If an original air and vapor mix-
ture is the only source of heat, evapora-
tion of enough vapor to saturate it will
produce a definite degree of cooling.
Practically, a current of air is blown over
the wetted surface of a sheathing of
cotton wicking wrapped around the bulb
of a thermometer. After a short lime
for the establishment of stable conditions,
this wet bulb will be lowered to a tem-
perature such that the latent heat of
the vapor formed will equal the sensible
heat lost by as much of the air current
as would be saturated by this vapor, at
the temperature of formation of the lat-
ter, or of the water. Since the sample of
' air takes up vapor in addition to its
original content, wet-bulb temperature is
higher than dew point.

POWER

The wet-bulb apparatus is called a
psychrometer. In a paper by W. H.
Carrier, on "A Rational Psychrometric
Formula," presented at the recent annual
meeting of the American Society of Me-
chanical Engineers, the thermal relations
involved in the action just described are
clearly developed, and by means of
charts are put into shape for convenient
use. To the ideal operation of saturat-
ing air by vapor formed wholly at the
expense of its own sensible heat, Mr.
Carrier gives the convenient and ac-
curately descriptive title of "adiabatic
saturation."

The effects of humidity and the prob-
lems of air conditioning may now be
briefly suggested.

The dew-point idea, in excess, is il-
lustrated by the sweating of cold-water
pipes, etc., in summer, and by the con-
densation on the windows of warm and
moist rooms in winter.

The wet-bulb idea is best exemplified
in the drying kiln, as for drying lumber.
Heat to vaporize the moisture in the wood
comes almost wholly from the hot air
blown into the kiln, so that this air is
subjected very nearly to adiabatic satura-
tion.

In the cooling tower, on the other hand,
evaporation is induced by air currents,
but latent heat is supplied by the descend-
ing stream of warm water, intended to be
cooled by this action. Consequently,
the saturation capacity is that of air at
but little less than the initial tempera-
ture of the warm water.

In heating and ventilation, the prob-
lem is to add vapor to winter air, which
is made excessively dry and thirsty by
raising it to indoor temperature; of
course, the formation and heating of this
vapor is an added burden on the heat
supply. If air is cooled for summer
ventilation, some of the vapor already
present must be removed, most readily
by supercooling, condensation and sep-
aration, to be followed by a partial re-
healing of the air.

When humid air is compressed, and
after the heat of compression has been
dissipated, most of the original vapor
content is precipitated; as the total pres-
sure is greater, the vapor tension (al-
though absolutely the same for a given
temperature) becomes relatively less,
with a resulting decrease in the weight
of air that can be carried by a unit of dry

December 12, 1911

air. Unless the air is cooled near the
compressor and the water is precipitated,
there will be an accumulation in the
pipes, with possible freeze-ups in winter,
and perhaps trouble with the tools and
the machines using the air.

In ihe operation of the blast furnace,
dry air is most desirable, since water
vapor is dissociated in the very hot zone
just within the tuyeres, absorbing heat
which is there much needed for the
metallurgical reactions; hence the recent,
most advanced scheme of refrigerating
and thus drying the blast between blow-
ing engines and blast ovens.

In all the examples so far cited, the
vapor tension and the quantity are rela-
tively small, but at the low pressures in
steam-engine condensers, vapor volume
is of the same order of magnitude as air
volume, in a saturated mixture. For
better effect in maintaining vacuum, mod-
ern condensers are so arranged as to
produce localized and progressive cool-
ing toward the outlet to the air pump,
thus diminishing the proportion of vapor
and the total volume of the mixture going
to the air pump.

In our issue of November 7, we were
made to say that only the gravity under-
feed stoker could carry an overload of
fifty per cent, continuously. It was the
publicity man of the gravity underfeed
stoker who furnished the test results
under consideration, and he slipped one
over on the man at the editorial bat by
getting through, along with them, the
above observation. We apologize to the
other stokers and — as for that pitcher,
wait until he gets into ihe box again.

Engineers are put on guard against a
new sort of explosion by an accident
which occurred recently at the Ayer mill
in Lawrence. In the overhead coal stor-
age is a concrete ash bunker, in the
form of an inverted pyramid some fifty
feet across, made sufficiently air tight to
allow a vacuum of fourteen inches of
water to be maintained in it. Into this
the ashes are drawn by suction from
the ashpits. Some weeks since an ex-
plosive mixture of gas was drawn over
from the boilers or generated from the
ashpit refuse which became ignited in
the bunker and exploded with consider-
able violence.

December 12, 1911

POWER

901

Underfeed Stoking vs. Over-
burning

During a recent national convention
of smoke inspectors, one of the members
took the position that to obtain the best
smokeless conditions, "underfeed stok-
ing" was necessary. Feeling that I could
not permit his statements to go un-
challenged. I ventured a few remarks
and it developed that what the gentleman
intended to say was not "underfeeding"
to produce smokeless combustion but
"overburning," as he termed it, which
might be construed as two quite dif-
ferent processes and yet after all that
was said, many of those present were
left with a cloudy impression of what
was really intended.

It is impossible to get perfect combus-
tion and maximum temperature under a
boiler by feeding coal up from below and
forcing air up through the incandescent
mass of fuel, although it is possible to
obtain high temperatures in the mass of
fuel itself.

I recently came across a work written
by George B. N. Tower, formerly chief
engineer of the United States Navy. This
book, written many years ago, is full of
the chemistry of combustion. Among Mr.
Tower's many deductions 1 find that some
are exactly to the points I raise against
underfeed stoking, producing as it does
a deep fire above the tuyeres and driven
by a forced blast from below.

Mr. Tower says the direct effect of
the union of carbon and oxygen is the
formation of carbon dioxide. If. however,
one of its portions of oxygen is ab-
stracted, the remaining proportions would
be those of carbonic oxide. It is equally
clear, however, that if a second portion
of carbon is added to carbon dioxide, the
same result will be had, namely, the hav-
ing carbon and oxygen combined in equal
proportions, as is seen in the case of
carbonic oxide.

Now, if these two volumes of carbonic
oxide cannot find the oxygen required to
complete their combustion, they pass
away necessarily but half consumed, a
circumstance which is constantly taking
place in all furnaces where the air has
to pass through a body of incandescent
carbonaceous matter..

The most prevalent operation of the
furnace, however, and by which the larg-
est quantity is lost in the shape of car-
bonic oxide is thus: The air on entering
from the ashpit gives out its oxygen to
the glowing carbon on the bars and ccn-
eratci much heat in the formation of

carbon dioxide. This gas, necessarily at
a very high temperature, passing upward
through the body of incandescent solid
matter, takes up an additional portion of
the carbon and becomes carbonic oxide.

Thus, by the conversion of one volume
of dioxide into two volumes of oxide, heat
is actually absorbed, while also the por-
tion of carbon taken up during such con-
version is lost, and one is deceived by
imagining that the "smoke has been
burned."

Smoke is a sure evidence of imper-
fect combustion; but, it does not neces-
sarily follow that where there is no
smoke combustion is perfect.

Mr. Tower quotes from Professor
Daniell, of England, as follows:

"Any method of insuring the com-
plete combustion of fuel, consisting part-
ly of the volatile hydrocarbons (com-
pounds of carbon and hydrogen) must be
founded upon the principle of producing
an intimate mixture with them of air in
excess in that part of the furnace to
which they naturally rise."

To bring the coal, in both its solid and
gaseous elements, into intimate mixture
with air, and to ignite the compound, are
all that human means can accomplish —
Nature only, in her own processes, effect-
ing the rest. The distilation of gas,
when fresh coal is supplied, goes on
near the surface of the fire; the gas
naturally burns above the surface, and
the air necessary for its combustion must
be admitted, therefore, above the sur-
face.

The question is often asked: "Why
not provide at once for the admission,
through the grate, of sufficient air both
for the coke and the gas?" This would
be an impossibility, for whatever the
quantity of air admitted through the
grate, il will expend itself on the coke
only- at least until holes arc burned
through the fire; then the control of the
air is at once lost, and great waste of
fuel ensues.

The admission of air above the flre
must be in the greatest practical number
of small jets, since gas and air mix

only gradually, excepting by division and
inducement. Air, in bulk, mixes only
superficially with gas, and by abstracting
heat cools the furnace. The air ports
should be placed as near as practicable
to where the gases rise, since, after they
are disengaged from the coal, it is neces-
sary to commence their combustion at
the earliest moment. Gases, to be thor-
oughly burned in the furnace, must be
intercepted by air at the start, else the
combination, which is at best gradual,
will not be completed in season, as what
remains uncombined on reaching the
tubes is lost.

There is a great difference between an-
thracite and bituminous coals. Anthra-
cite burns completely with a thin fire, by
admitting an excess of air through it and
above it; but bituminous coal absolutely
requires for its perfect combustion a
high temperature and plenty of room for
the products of combustion, before they
come into contact with the iron of the
boiler, together with a proper supply of
air above the fuel. Any deviation from
these conditions produces smoke and loss
of heat.

Orosco C. Woolson.

New York Citv.

Took Cia.ses from the Uptake

Some time ago 1 had a good demon-
stration on chimney waste in burning
coal. I was using No. 2 buckwheat
mixed with soft coal in proportion of one
to seven, just enough to give body and
not smoke. 1 used a patented steam
blower for forced draft, and kept the
damper open far enough to keep the
names from blowing out the fire doors.

One day there was a slight explosion
in the front connection and on opening
the doors 1 found that a part of the arch
had fallen out, making a short cut for
the flames and the gas which burned in
front of the tubes and toward the
damper.

This occurred each time fresh coal was
put on the fire, and continued until the
fire burned up brightly. After the arch
was repaired, I made a hole through the
brickwork, as shown in the sketch, using
ordinary 5-inch stovepipe. The bottom
end just fitted in the steam ring of a
blower, so that it drew the gases down
into the ashpit, and so up through the
fire.

Fresh air was drawn in around the side
of the ring, and the changed furnace
condition could readily be seen. On ac-

902

POWER

December 12, 19! 1

count of the shaking bars the ashpit
could not be made air tight, so that each
time fresh coal was put on the gases
coming out were choking; but the brick-
work in the combustion chamber got so
red hot that I could see the rivets on
the rear head of the boiler.

On testing with and without the gases
being returned, I found the average evap-
oration without the return was 6.9 pounds

then continues to rise in the tank until
ir reaches the inlet of the stopping pipe
pnd flowing to the cylinder reverses the
action of the piston and lever which
closes the filling valve on the discharge
pipe from the pump.

The globe valve on the stopping pipe
is only used to show that the tank is
full. When testing, the globe valve is
closed, and the piston is pushed in by

Gas Bypass to Ashpit

of water per pound of coal, and with
the return 7.9 pounds of water per pound
of coal. On account of changing to soft
coal shortly afterward 1 was not able to
experiment further with the arrangement.
H. L. Breckenridce.
Belleville. N. J.

Controller for Water Tank

I have used several kinds of tank
gages and have not found one that is
reliable at any distance from the tank,
so I have discontinued their use and
constructed the device illustrated here-
with.

The device is placed on the bypass or
filling-pipe line. After the tank is once
filled and the pipes connected, the water
never gets below the compression cock
or higher than the stopping pipe unless
the tank is to be overflowed.

When the water in the tank gets down
to the lower level or just above the
compression cock, the ball float, having
been set to open at this point, the water
enters the cylinder through the starting
pipe, pushing the piston and rod into the
cylinder. This action partially turns the
cam on the valve stem on the line lead-
ing from the pump, which is controlled
by a pump governor. This opens the
valve and the water is then pumped into
the tank until it lifts the ball float which
closes the compression cock. The water

W.4rER Tank and Controller

the lever. The tank will then fill to over-
flowing, and when the valve is opened,
the filling valve will be closed as before.
The globe valve should be left open at
all other times.

In each end of the cylinder a small
drain hole is drilled and fitted with a
pet cock which is left open to drain the
pipes as well as the cylinder. The size
of the cylinder depends on the hight
of the tank. 1 used a 3-inch brass tube
on a (lO-foot tank.

In adjusting the cam on the inlet valve,
the large part of the cam should rest on
the stem when the valve is closed; this
prevents the valve opening when the
cylinder is relieved of its pressure.

J. E. J. GOODLETT.

Memphis. Tenn.

Hump C'au.sed Pound

It was a 17 and 34 by 42-inch engine,
running at 104 revolutions per minute
and developing about 400 indicated
horsepower.

I' ran from Monday morning until the
next Sunday morning.

When the engine was first started
after erecting, it had a slight pound,
but the load was light and the connec-
tions were taken up two or three times
a week so the erecting engineer got by
all right.

But when more load came on, the
engine pounded hard and the hunt be-
gan; and no matter w-here one listened,
the pound seemed to be there.

Engineers from other plants gave their
opinions, and their ideas were all tried
out. but with no results.

One Sunday I disconnected the con-
necting rod from the crosshead, and
found on the inside of the strap a hump

Defective Crank-rod End

in the steel, as shown in the sketch. I
smoothed the hump off, which was about
% inch, connected the rod and when
I started, Monday morning, the pound was
gone. I cut the hump off about a year
ago and the engine has not pounded
since.

R. A. Hafford.
Groveton, N. H.

Knocking in Air Compressors

A double connecting-rod air compressor
will frequently knock badly unless the air
valves are in good condition and the
steam valves are properly set. The knock
is caused by the elastic spring of the air
in the air cylinder acting against the
steam piston when the steam is expand-
ing, due to the cutoff. This trouble can
be eliminated in part by setting the steam
valves so as to allow plenty of steam to

DoiBLE Crank Compressor out of
Adjustment

follow up the piston and not cut off too
early.

Straight-line compressors should have
the valves set on the steam end so that
the air valve will be closed on the com-
pressor end when the steam piston is
nearing the end of its travel; otherwise
the elastic body of air will cause a bad
hammer.

Some knocks are caused by a wearing
of the side-rod brasses. I have found
them on double-rod machines so worn
that one rod would be 1 '16 inch longer
than the other.

Sometimes the crank pins are not
equally distant, as shown in the illustra-

December 12 1911

POWER

903

tion. New babbitt in the crank-shaft
bearings or thin copper liners between
the end of the connecting-rod brasses on
the short-rod end would remedy the de-
fect.

Baltimore. Md.

C. R. .McGahey.

H(n V\ atcr Supply

A friend of mine who hates to see a
heat unit wasted rigged up the outfit il-
lustrated herewith. Originally the 1-
inch drip from the exhaust pipe dis-
charged direct into the sewer. He had
an old closed steel tank about 4 feet
square and he connected the drip as
shown, A being a coil of 12 pipes wide
laid upon the bottom of the tank and dis-
charging into the sewer. The drip pipe
keeps the water hot in the tank and it

placing a ring around the flange part, Eninilf Room Crane
when broken as shown at B, or a plate

can be cut as shown at C. This plate '" engine rooms where no traveling

may be slipped over the piston or valve power crane is provided, much time can

^ ,y<:^^^^^^^^^:^-^ ^^ saved by rigging up permanent spe-

Mfthcd of Repairing Broken Stuffinc-box Glands

rod, and held against the gland cover
by the nuts of the gland studs.

W. E. Bertrand.
Philadelphia, Penn.

The Superintendent Knew

I had a call from the superintendent
to bring my coal records to the office
when he asked why it was necessary
for me to use so much coal with a light

load.

Exhaust

Header

Arrangement for Heating Water

can be drawn off for use at the faucet.
The tank is refilled at any time from
cold-water supply fi. The water is abso-
lutely clean as the tank has a good cover.
J. K. Noble.
Toronto. Can.

Repairing Stuffing Box Gland

An engineer is not necessarily "up
against it" because a stuffing-bo.x gland
breaks.

Large glands, such as arc found on
plunger pumps, may be repaired by
shrinking a ring around the outside of
the flange, and then turning down the
boss and shrinking on a ring, as shown at
A. Where appearance, or small clear-
ance, prohibits an increase in the out-
side diameter of the cover. i» can be
clamped together temporarily, and turned
down to the sludbolt holes, the metal
turned off being replaced by a ring.

Small gland covers can be repaired by

I stated the number of pounds of
water evaporated per pound of coal, and
he went to work and wrote down a lot
of formulas, but I doubt if he knew what
they meant. However, after figuring for
a while he said that I was not doing quite
?o badly as he thought; I was burning
only 80 pounds of coal per horsepower
per hour.

On another occasion it was necessary
to operate the plant noncondensing. When
I turned in my chart for the month the
superintendent said : "Now, let us see
how much more coal it takes to run high-
pressure than it does condensing."

He went to work tracing the chart I
gave him and finally said that it look onlv
700 pounds more, which did not offset
the cost nf the condensing system. I
cpncluded that if he could not read a
chart heller than that. T would not tell
him the difTcrcnce,

E. W. Roth.

Chicago, III.

cial devices to lift and convey parts
of machinery subject to repair and in-
spection.

The crane illustrated herewith is for
removing cylinder heads, but is equally
adaptable to the main journal and out-
board-bearing caps or connecting rods
and is so simple in construction that it can
be made by any engineer out of other-
wise useless material generally found
around the plant.

The rail is made of a piece of 4x6-inch
— timber stronger if necessary — bolted

Hnnf Truss

HoMi'MAnE Enoine-room Crane

up under the roof trusses in a position
central to the work. The rollers can be
made of flanged pulleys from an old
rope-drive tension carriage, or a simple
pulley; the width of the rail will do
equally as well.

The outfit is completed by a v^-inch
round-iron axle supporting a clevis of
the same material from which is sus-
pended a hook rod with turnbuckle.

An arrangement of this kind makes
frequent inspection of the piston rings
and cylinder an casv task.

F. C. HOLIY.

Yazoo City, Miss.

904

POWER

December 12, 1911

y *

Apparatus for Distill in ji; Water

Some time ago August A. Speclit asked
for suggestions as to how he could get
distilled water for his storage batteries.

I suggest that he get a cast-iron closed
heater of about 75 horsepower, also a set
of gages and glass, and attach them to the
heater so as to indicate the water level.
He should bypass the exhaust line of the
engine he uses most and regulate the feed
water to the heater either by hand or by
float-valve control. The heater should
have a IJi-inch outlet without a valve.
A coil of a size to fit into a barrel of
water to act as a condenser should be
obtained and both ends carried up to
the top of the barrel, one end connecting
to the bypass pipe, the other leading
to another barrel alongside the first.

This arrangement will provide all of
the distilled water required at a total

piping should be of copper or brass, as
distilled water is very hard on iron or
steel pipe. The diagram shows the man-
ner of piping the outfit.

D. L. Fagnan.
New York City.

Central Station Sales MethocU

In the October 24 issue, R. L. Ellis,
under the caption "Why the Central Sta-

DlsfUled
Wafer,

.<'//!l!!l-LLlV

IT

DlSTILLED-WATER APPAR \

%>Mihm

cost, including labor, of -SI 50. .^bout
five barrels of 40 gallons each will be
required per week and it would only be
necessary to operate the outfit about one
day in the week to obtain all the water
needed. In case a smaller outfit is
wanted to operate continuously, a 25-
horsepower heater connected on the line
will be satisfactory and will be much
cheaper.

The water obtained in this way is pure
and the cast-iron heater will last for
many years. The bent coil and all the

tion Catches Isolated Plant Business,"
states that central-station solicitors do
not deliberately mislead their prospective
customers.

I beg to differ with him; there arc
many instances where, either wilfully or
through erroneous ideas of what is legiti-
mate business, misleading information is
given to the prospective customer.

In Power of February 14; 1911, under
the head of "Central Station versus Fac-
tory Plant," I called attention to two
instances which came to my notice. In

1911, is an article by a Mr. Fletcher,
giving a report furnished by a central
station which is glaringly at fault, show-
ing considerable possibilities in other di-
rections than in the installation of cen-
tral-station power. In the Electrical World
of July, a Mr. Perry gives a report which
when carefully analyzed shows that it is
distinctly unwise to install central-sta-
tion power and that far greater economies
can be obtained at less expense by tak-
ing proper care of the plant. In the
American Institute of Electrical Engi-
neers Transactions there are articles by
Messrs. Hibner and Parker, bringing up
numerous ideas, the principal one of
which is the profit ratio, a justification
of which factor has as yet not been
brought forward.

These articles in themselves show that
the central-station advocates are not al-
ways fair in placing their arguments be-
fore prospective customers. I have had
frequent conversations with other engi-
neers since the matter of central-station
versus isolated-plant power came up, and
they have in almost every case made
the statement that the central-station
solicitors as a rule overestimate the cost
of power in the industrial or isolated
plant, and underestimate the cost of
power as it will actually be furnished by
the central station.

Little or no care seems to be taken in
the type of motors or the installation of
motors recommended by the central sta-
tion, the main object being to get central-
station power into the factory plant. The
only excuse I can see is the apparent
belief that, once having installed central-
station power and expended the money
necessary to get it in, they feel that the
owners will hardly consider wasting this
money to take it out.

It is quite true, as stated by Mr. Ellis,
that it is not the duty of the salesman of
the central station to take care of the
isolated plant and show its owners what
they can do to improve their plant in
other means rather than install the cen-
tral-station power; but it is equally true
that the central-station solicitor should
not make misleading and false state-
ments, nor should he try to do the en-
gineering for the prospective customer.
If there is any question in the mind of
the owner, the central-station man should
put it up to some reliable man, either the
engineer of the prospective customer if
the engineer is capable of handling it, or
recommend some unbiased man to the
purchaser, so that the work will be care-
fully and accurately done.

December 12, 1911

POWER

905

If the central stations get their busi-
ness under false pretenses and the pur-
chaser finds it out, he will spread this
report broadcast and seriously handicap
the central station in getting future busi-
ness.

Henry D. Jackson.

New York City.

Engineers' Wages

The first-page article which appears
in the October 31 issue is particularly
strong and suggestive.

The picture of the steamfitter "doing"
a job, and the intelligent-looking in-
dividual directing the other how and
what to do, speaks volumes. But no one
would for a moment suppose that the
man on his feet could actually be getting
less pay for what he does than the man
on his knees gets for what the other tells
him to do, if he were not familiar with
the inside facts. If the onlooker is
familiar with actual facts and conditions,
then, of course, the picture does not rep-
resent the "eternal fitness of things," but
rather "the incongruity of things."

That article and its illustration should
set not only the employers of engineers
to thinking, but the engineers themselves,
for they have been patiently waiting and
hoping to come into their just inheritance
for a long time.

It is true that comparatively few have
had their patience rewarded and their
hopes realized, but the great majority of
operating engineers all over the countO'
are not much better in surrounding con-
ditions than they were 25 years ago. And
this in spite of the fact that many of
them have learned more and are better
equipped mechanically and educationally
than ever they were before.

Charles J. Mason.

Scranton, Penn.

I read the foreword in the October 31
issue with a great depth of appreciation
and satisfaction because every word as
set forth therein is strictly true, and in
keeping with the situation at the present
time.

It is true the operating engineer has
been laboring for years to make for him-
self a place that will be a credit to him.
and put him in a position of respect and
bring him a reward commensurate with
what he really knows and does. This
he has not realized, and when the steam-
fitter or machinist or plumber or elec-
trician or bricklayer or, in fact, a mem-
ber of any of the allied trades comes
in to do a job for him. and the bill is
sent from the office for his approval, it
sets him to wondering what it all means.

A most peculiar fact is that sometimes
when a capable engineer grows tired of
things to the extent that he quits the
job, the employer seems willing to labor
along under the most adverse conditions
for weeks and months, losing mnncv

every day to an amount far in excess of
the small difference in salary asked for
by the engineer, when a few words of
inducement would have permanently ad-
justed the whole matter and put an end
to the costly annoyances thrust upon the
employer and apparently borne with such
ease.

There must be a solution somewhere
to this situation, and it strikes me that
the foreword under discussion should
awaken both the employer and the en-
gineer.

Ja.mks a. Okr.

Elizabethport, N. J.

Loose Crank Pin

Referring to Mr. Hawkins' discussion
in the October 24 issue of my letter in a
previous issue concerning a centrifugal
oiler which unscrewed from a loose
crank pin. I will say that the engine was
a left-hand one running over.

The ball on the end of this centrifugal
oiler did not leave the horizontal oil pipe
until the oiler dropped from the pin;
therefore the pin must have turned in the
disk until it screwed off of the oiler; to
do this it must have turned in the disk
in the same direction as the crank shaft.
My assistant was feeling of the crank-
pin brasses when the centrifugal oiler
dropped the third time. At first I thought
that the pin held in the crank-pin brasses
while turning in the disk, but I had to
give up that idea as this would cause the
pin to turn in a direction that would screw
it onto the end of the centrifugal oiler.
I have since come to the following con-
clusion: •

When the bead at the end of the
pin was chipped off, the pin was so loose
in the disk that it could be pushed out
with a hammer handle. Now. assume that
there was a little lost motion in the
brasses. As the engine near the inside
dead center before the lost motion in the
brasses is taken up by the compression
or the admission of steam, the weight
of a part of the connecting rod acts
downward on the top of the pin while the
latter is traveling upward. In this posi-
tion, therefore, the friction due to the
weight of the end of the connecting rod
will cause the pin to rotate over to the
right when the lost motion is taken up.

As the pin nears the outer dead cen-
ter, before the lost motion is taken up
by compression at this end, if the con-
ditions here were the same as in the
other case, the pin would be rotated back
to its first position. But the conditions
are not the same.

The weight of the end of the connect-
ing rod acts downward as before, but
the pin is also traveling downward, and
as the pin is moving about 1.S feet per
second if is running away from the weight
of the connecting rod.

Under these conditions, when the lost
motion is taken up at this end, the pin

would still tend to rotate over to the
right. I do not think that the friction of
the pin on the lower side of the brasses
will be great enough to cause the pin
to rotate on this dead center, but it cer-
tainly will not lose what it gained on the
inside dead center.

This rotation of the pin on the inside
dead center would be but a small frac-
tion of an inch each time, but it would
eventually turn the pin enough to screw
off the threads on the oiler. These were
right-hand threads.

L. A. FlTTS.

West Fitchburg. Alass.

Value of CO.. Recorder

I have read with interest the dis-
cussion under the above heading. The
main issue. I think, lies with the deter-
mination of CO: itself. Is the knowledge
of the percentage of CO; in the flue gas
of any value? The foundation of all
the theories on flue gas is the fact that,
assuming the temperature to remain con-
stant, the loss of heat in the waste gases
decreases with the increase of the per-
centage of CO.. The only doubt to be
raised is whether the temperature will
rise with the CO:. At some tests made
by the Government at St. Louis in 1906
it was found that the temperature of
the stack rose with the rise of tempera-
ture in the combustion chamber. Now
as the combustion chamber is hotter with
higher CO: it follows that with higher
CO: higher llue temperature may be ex-
pected. I have not heard of this result
being confirmed or disproved since 1906.
Even if this is true, there must be an
economical point at which to carry the
CO: in order to get a minimum loss up
the chimney. As to CO and uncon-
sumed hydrocarbons, there must also
be some economical point at which to
carry the CO: so as to get the losses due
to these down to the minimum. Now. if
one has the complete analysis of a sam-
ple of flue gas and its temperature, he
can calculate fairly accurately the losses
up the chimney provided the sample is a
true one.

When the percentage of CO: is high
it is expected that a heavy or a close,
even fire, and a tight setting will be
found; in other words, a minimum of air
leakage. When the amount of CO: is
low, a dirty fire, bare spots on the grate,
leaks in the boiler setting, etc., will be
found. When the quantity of CO; is low
the losses up the chimney are high, but
it does not follow that when the per-
centage of CO: is high that the chimney
losses are correspondingly low. It is
this last idea that misleads most people
in (heir estimation of the value of the
COi determination.

Now as to the CO, recorder. First,
many object to the fact that it is next
to impossible to get an average sample

906

POWER

December 12. 1911

of the gas from the uptake. A large
number of schemes have been suggested,
but if a single pipe is employed going
to about the center of the uptake, the
sample will not be far from the average.

As to the determinations: Some types
of machines give a continuous record,
others make analyses at intervals of two
minutes or more. With an Orsat a man
could not make a determination every 15
minutes very long. All personal errors
are eliminated by the machine. There
is no toilsome crawling over boilers or
behind boilers to get the gas sample. 1
would say that if an Orsat were used,
one or two determinations from each
boiler a day are all that could be counted
on and these are worth very little. The
cost of a CO; machine would not exceed
$100 per boiler and if a man is em-
ployed especially to get gas tests with
an Orsat. his wages would soon pay for
the machine, not to speak of the enor-
mous difference in the service in favor
of the machine. Supposing the machine
takes 15 per cent, of its cost for repairs,
etc., per year, the intelligent use of the
machine would probably save this in a
week. If no saving could be effected, it
would be worth S15 per boiler per year to
know that conditions were somewhere
near right. That much could be saved
by preventing an outlay of money for
unnecessary things advised by unscrup-
ulous people wishing to take advantage
of one's ignorance of actual conditions.

I have known fuel experts to make a
gas analysis with an Orsat at the rear
of the boiler and then later (at least 15
or 20 minutes) take another at the exit
of the economizer, figuring the air leak-
age from the difference in the CO:. Now
in that time the gas can change within
very wide limits. In one case the CO,
was higher back of the economizer than
in front of it, which is absurd; neverthe-
less, these figures were turned in and
great stress was laid in the report on
air leaks. The management received them
in good faith, assuming them to be ab-
solutely correct.

If a COl- machine and a recording
pyrometer are installed 1 believe, by a
little experimenting with the dampers
and the fire, together with careful think-
ing, great savings in fuel could be
made. However, if the percentage of
CO.- is going to be taken as proportional
to efficiency without any other considera-
tion, the CO;- machine will not be a suc-
cess. There is too much tendency to as-
sume that raising the CO,- a slight per-
centage has made a big saving. If prop-
erly cared for and intelligently used, a
CO.- machine, especially in connection
with a recording pyrometer, Is a very
valuable accessory in the boiler house
and in many cases would quickly pay for
itself and keep on saving money at the
same rate.

James E. Steely.

Covington, Va.

Cylinder Oil Tested
Actual Service

for

In his article "Cylinder Oil Tested for
Actual Service," H. B. Lange, in the No-
vember 7 issue, does not, to my mind,
prove that 3 pints of cylinder oil were
necessary to properly lubricate the cyl-
inder and valves of the engine under dis-
cussion, except under the operating con-
ditions described; for, if the condition of
the crank-end exhaust valve were
changed, I believe It would be possible
to reduce the amount of cylinder oil
used to at least 2 pints. I presume that
the engine mentioned is of the four-valve
nonreleasing-gear iype, which usually is
equipped with two eccentrics.

Mr. Lange says that after the test run
of 10 hours, when 1.948 pints of cylinder
oil were used, the crank-end exhaust
valve was removed and showed two dis-
tinct spots of wear which were not there
before the run. My deductions are that
the two spots showing wear are high
spots on the valve which are sustaining
a much larger portion of the pressure of
the valve on the seat, due to the pressure
of the steam and the weight of the valve.
Assuming that the travel of the exhaust
valve varies with the load, and that the
lighter load is carried longer than the
heavier, the valve would make the short
stroke oftener than the long and the high
spots may have worn grooves in the
valve seat which allow an even distribu-
tion of the load on the valve during light
load.

I believe, if this valve is fitted to its
seat, that the cylinder oil used may be
considerably reduced without any further
trouble.

A. K. Vradenburgh. ■

Albany. N. Y.

The Loose Leaf Book Habit

in the course of many visits to power
plants on a recent 9000-mile trip around
the country, it was most interesting to
note the remarkable differences in prac-
tice which are to be found among op-
erating engineers. To take a single point
as an example, nothing showed the in-
dividuality of the men holding responsible
positions in this fiald better than the
way in which their station data and rec-
ords were kept. Of course, it is clear
enough that no single system of keep-
in„ track of installation and service de-
tails will meet the requirements of all
types of plants, but that some system
should be scrupulously maintained was
one of the most important lessons of the
whole journey.

It may be a little late in the day to
start a monologue on the subject of rec-
ords of station equipment and operation,
especially to the man who has been run-
ning a system of this kind for many
years past. But If Powbr readers could

have gone on this trip and seen the need
of such methodical work In more plants
than I would like to count, there would
be no complaint because reference has
again been made to a rather threadbare
topic.

The men who are handling their plants
in the most broad-gage manner are the
ones who are never at a loss to answer
reasonable questions concerning the
capacities and sizes of their equipment;
who can turn at an instant to the per-
formance of the station at any hour of
the day for months past; who save time
in ordering supplies and spare parts
through reference to carefully prepared
lists of material and fittings gathered
from actual experience and tabulated
either In Inexpensive filing folders or
neat loose-leaf books.

Still, there is room for improvement,
particularly in the direction of furnish-
ing operating engineers with complete
sets of drawings of their plants and
equipment arrangements, w'hen such In-
formation has been prepared for use by
the designing department. It is surpris-
ing how much good is accomplished by
the simple scheme of filing blue-printed
station-load curves in, say, 8xl0-inch
sheets perforated at the edges for in-
sertion in a loose-leaf book on a time
basis, when the demand arises for the
presentation of data bearing upon out-
puts.

In one plant visited, the engineer In
charge had supervision over several
large and small hydroelectric generating
plants, one or two steam stations and a
score or more of substations. The keep-
ing of data bearing upon the dally per-
formance of all this equipment was so
important on this system that a clerk was
detailed to keep special watch of the
work. The chief engineer, however, main-
tained in his office a set of loose-leaf
books for each substation and generat-
ing plant, and as these were filed for
individual portions of the system accord-
ing to dates, it was possible within a
few seconds to determine the load upon
the system -.t any important point and
at any dcy and hour for months.

The scheme was of the greatest assist-
ance in determining the fitness of the
existing equipment to meet the demands
of the service, and when the question
of extensions came up, with its added
responsibilities for the operating force
and tendency toward Increased salaries
resulting from the larger values placed
in the hands of the men on shifts, the
loose-leaf data sheets of loads were im-
portant factors in avoiding delayed plans
for enlarged installations.

H. S. Knowlton.

Newton, Alass.

The Institute of Operating Bogineers
has been instrumental in securing nine
positions at salaries frora S520 to S2080
for its members.

December 12. 1911

P O ^' E R

907

Boiler Tube Failure

The boiler-tube failure shown in the
accompanying illustration occurred dur-
ing a test, made some time ago, upon a
Babcock & Wilcox boiler at the Redondo,
Cal.. power plant of the Pacific Light
and Power Company. The tube was made
of No. 10 gage lap-welded charcoal iron,
4 inches in diameter, and failed under a
steam pressure of 185 pounds. The ex-
plosion fortunately resulted in no disaster
other than placing the boiler out of ser-
vice. The break is remarkable in size,
being 5 feet long from tip to tip; at
the central portion, as wil> be noticed,
the tube is as flat as a board.

The boiler has a rating of 604 horse-
power, and consists of 21 sections of

Break in Tube 5 Feet Long

fourteen 4-inch tubes 18 feet long. It
is designed for 200 pounds working pres-
sure, 175 pounds being carried under op-
erating conditions. The unit is equipped
with a forged-steel superheater, which
gives about \<)0 degrees Fahrenheit at
the boiler nozzle. Ordinarily, 4-inch hot-
drawn seamless steel tubes are installed,
the charcoal-iron sections used at the
time of failure being primarily for the
purpose of testing what they would bear
in actual service. The accompanying
photograph was taken by Orie Brian,
formerly in charge of the boiler room
at the plant.

Fatal Marine Boiler Fxplosion

The steamer "Diamond" was blown to
pieces by a boiler explosion in the Ohio
river near Davis Island dam, about five
miles below Pittsburg, Penn., on Decem-
ber 2. Five men, including the captain,
were killed and two were severely in-
jured. The engineer and two firemen
were among the killed. The "Diamond"
sank immediately in midstream.

The cau<<e of the explosion is unknown.
No trouble had been experienced with the
boilers. They had been inspected on
June 23, 1911, and a certificate nf in-

spection one year from date had been
granted by Government inspectors.

Owned by the Diamond Coal Company
and operated as a towboat for a line of
coal barges, the boat had towed some
coal barges to East Liverpool and was
returning to Pittsburg when the explo-
sion occurred.

President Meier' ,s Address at

Annual Meeting of the

A. S. M. E.

The address of Colonel Meier, retiring
president of the .American Society of Me-
chanical Engineers, at the annual meet-
ing on December 5, traced the rise of
the engineering profession from a very
meager beginning to the important place
it now holds. His remarks were in part
as follows:

".\ century ago the distinction between
the civil and the military engineer suf-
ficed, but later it became necessary to
differentiate in turn the mechanical and
the electrical engineer, while quite re-
centh- upward of a hundred specialties
were enumerated in the attempt to de-
fine the activities of the profession.

"Slowly but surely the superstitions
and traditions which so long encumbered
social life and hampered free develop-
ment, are exposed and annihilated by the
altruistic labors of men who give their
life to science. It is the duty of the en-
cineer to receive these discoveries and
apply them to the solution of the prac-
tical problems of life.

"Those great road and bridge build-
ers, the Romans, produced military en-
gineers, but theirs were mainly static
problems; and even their much vaunted
aqueducts show lack of cooperation be-
tween science and practice. They were
carried over valleys on costly structures
inviting destruction at the hands of the
enemy. With their excellent cement and
their knowledge that water always seeks
its level, their engineers might have
built subterranean conduits.

"Early in the nineteenth century the
scientific method came into vogue, and
henceforth problems were studied and
defined before their solution was at-
tempted, and more intellectual labor was
expended in ascertaining facts than in
reasoning about them. Thus the union
between the mechanic and artificer and
the student of nature's laws became pos-
sible and permanent, and engineering de-
veloped from an art into a profession.

"The engineer is a devout believer in
natural laws; he knows that ihey are
immutable and permit no exceptions; he
needs no supreme court to define them
as reasonable — Ihey are the very
foundation of the universe, and reason
itself owes lis existence to them. Every
infraction of them brings its own punish-
ment. To men thus trained, the future
of the race Is to be confided.

"The enlightened man loves his work
and finds in it his supreme incen-
tive. To a Copernicus or a Newton,
a Watt or a Corliss, an Ericsson or a
Fritz, an Edison or a Steinmetz, the ran-
som of a king would seem trivial com-
pared with the satisfaction of knowing
that he has given to his fellow men an
achievement which marks a forward step
in the evolution toward a race of rational
beings.

"The unrest in the modern world has
its basis in an underlying sense_ of in-
justice. The growing sense of com-
munity of interest, the knowledge of our
dependence on each other, the ever ex-
panding humanitarianism, are all founded
on scientific facts, and are becoming
world movements.

"The engineer is responsible for the
vast increase in appliances to meet every
demand of that most voracious of living
beings, man. The mass of mankind needs
to be educated to understand and use
them properly. He is in honor bound to
supply this education; and as the crude
dangers and fears of the earlier cen-
turies vanished, so the prejudices and
superstitions of the dark aces are being
swept away. '

Doctor Huniphrevs President
of A. S. M. E.
Dr. Alexander C. Humphreys, presi-
dent of Stevens Institute and the fore-
most gas-plant engineer in this country,
has been installed as president of the

Dr. Alkvandkr C. Himihreys

American Society of Mechanical Engi-
neers.

Colonel Meier, the retiring president,
in introducing Doctor Humphreys, paid
tribute to his fitness for this new position
and briefly sketched his early life and
slriigglcs in acquiring an education.

In the face of circumstances which
would have seemed insurmountable to
the average man, Mr. Humphreys gradu-

908

POWER

December 12. 1911

ated from Stevens Institute with the
class of 1881, having accomplished for
the most part at night, after a day's
work had already been done elsewhere,
what normal students fresh from ad-
vanced schooling accomplish only by un-
remitting application of all their working
time.

Soon after graduation, Mr. Humphreys
became chief engineer of the Pintsch
Lighting Company, of New York. In 1885,
he was made superintendent of construc-
tion for the United Gas Improvement
Company, and shortly afterward took the
position of general superintendent, with
headquarters in Philadelphia.

Eventually he assumed control of the
entire commercial management of all the
company's works, including the Welsbach
Incandescent Lighting Company, which
at that time was a subsidiary of the
U. G. I.

In August, 1894, Mr. Humphreys re-
tired from his official relations with the
United Gas Improvement Company to
establish the firm of Humphreys & Glas-
gow, of New York, recently succeeded by
the firm of Humphreys & Miller, Inc.,
of which he is president.

In June, 1902, Mr. Humphreys was
elected president of Stevens Institute of
Technology, by unanimous vote of the
trustees. In 1903, the degree of doctor
of science was conferred upon him by
the University of Pennsylvania, and the
degree of doctor of laws by Columbia
University. New York University also
conferred the degree of doctor of laws
in 1906, and Princeton University in
1907.

Doctor Humphreys has been the chief
executive officer of more than fifty-five
gas and electric-light companies, and is
now president of the Stevens Institute of
Technology, Humphreys & Miller, Inc.,
gas engineers, and the Buffalo Gas Com-
pany. He is a director in the Equitable
Life Assurance Society, a member of its
executive committee, and a trustee mem-
ber of the executive committee of the
Carnegie Foundation for the Advance-
ment of Teaching. He is a member of
almost every prominent technical society
in this country; of the Delta Tau Delta
Fraternity, and of many clubs and phil-
anthropic societies, to all of which he
gives liberally of his time and strength.

In assuming the duties of president of
the American Society of Mechanical En-
gineers, he is adding greatly to his pres-
ent responsibilities, and yet such is his
capacity for service for others that the
affairs of the society will be in as sure
and safe hands as ever before, and the
society is fortunate indeed in having him
for its president.

In accepting the presidency. Doctor
Humphreys referred to the fact that the
society was organized at Stevens In-
stitute and that Doctor Thurston, then
professor of mechanical engineering at
the Institute, was elected its first presi-

dent. In acknowledging the honor con-
ferred upon him he referred to the heavy
responsibility involved in accepting the
office, especially in view of the dividing
and subdividing of the engineering pro-
fession into so many specialties, and in
this connection he referred to the move-
ment recently inaugurated in the so-
ciety by the appointment of subcom-
mittees of the meetings committee to pro-
vide studies and papers on the many in-
dustries which might be considered as
related to the profession of mechanical
engineering, there having been about forty
such committees suggested with, no
doubt, more to come.

While recognizing the need for this
closer and closer specializing in engi-
neering and industrial management, he
deprecated the multiplication of societies
and expressed the hope that means would
be found to keep the direction of this

the extension of the society's activities
along the lines referred to would call for
greatly increased financial support.

Colonel Meier' .s Portrait for
the A. S. M. E.

As the seventieth birthday of Col.
Edward D. Meier, retiring president of
the American Society of Mechanical En-
gineers, occurred on Memorial day, dur-
ing the Pittsburg meeting of the society,
a large number of the members united
in a subscription and presented to him an
illuminated address of congratulation, as
previously reported in these columns, and
also asked his consent to give sittings for
a portrait. This portrait has just been
finished and will be on exhibition in the
rooms of the society at its annual meet-
ing in the Engineering Societies building,

Portrait of Col. E. D. Meier

movement within the society while pro-
viding the fuller measure of home rule
for each section consistent with an effi-
cient system of cooperation. To develop
a system of such wide scope would re-
quire great good judgment and tact on
the part of all concerned, for the op-
portunities for disagreement and friction
must, for safety, be at once recognized.
Here would be an opportunity for the
engineers of the country to show their
capacity for effective ser\'ice in the com-
munity at a time when such service is
needed as never before.

He also drew attention to the fact that

New Y'ork, December 5 to 8. The portrait
represents him in a pearl-gray suit and
sitting in a rather easy position.

The artist was Daniel J. Strain, vice-
president of the Boston Art club, whose
studio has been in Boston for a number
of years. Mr. Strain is one of the lead-
ing portrait artists, and among his works
are portraits of many of the leading men
of the East. He was born in New Hamp-
shire and studied for eight years in Paris.
His works have been admitted to the
Salon on three different years and he is
a frequent exhibitor at art exhibits in
this countr\-.

Vol. -H

^E^V YORK, DECEMBER 19, 1911

X... 25

FOOTBALL is a great game. Many people con-
demn football, saying, "It is brutal." We
must admit ourselves that it w a bit strenuous,
but so is piano-playing for the man who has a run-
around on the tip of each of three fingers.

Well, then, the ayes have it; football is a great
game for these reasons :

It teaches discipline and self-control. Ever)' rule
of the game must be scrupulously observ'ed, and in
the excitement of the moment and anxiety to win,
some of them are mighty hard to remember. When
you are keyed up to the highest pitch it is not always
easy to wait until the ball is ".snapped" before you
start your lunge at the opposing line. If you do not
wait, however, you are "offside" and your team is
penalized ten good yards for your over-eagerness —
if the umpire sees you. If it happens too often you
will find that you are not as great a football player
as you thought you were — not near — because the
loss due to a penalty of ten yards is greater than the
probable advantages of a great nuinbir of offside
plays.

I'ootball teaches perseverance
— stick-to-it-ive-ne.ss. For instance,
the ball has been worked down the
field until it is on the ten-yard line
of one of the teams. Does this team
lie down and play dead just because
things kK)k dubious? Not by any
means. The team puts every last ounce
of effort into its play. And often those
last ounces are just what is needed,
for just as often the tables are com-
|)letely turned and a well deserved
tally is scored.

Football teaches alertness, re-
sourcefulness and that physical fit-
ness is important.

Best of all, football teaches tnie sportmanship.
A successful footballist bucks the line hard, plays fair,
]nits up when he loses and shuts up when he wins.

\\'e heard that remark! Somebody over there
in the back row said, "What in the name of Hocus
Pocus has all this to do with operating engineers and
their vocation?"

Just this: Football is a whole lot like the game
of life; the same things that count in the one count
in the other. Those very qualities so essential to
a good football plaj^er are the same that any
man might well cultivate, no matter what his occu-
pation.

In the long nui, jvni cannot win by playing off-
side, either in football or in operating engineering.
You must play square and obey the rules.

You cannot win by being a quitter. Of course,
you get uj) against a tough jjroposition now and then,
but every difficulty that you succeed in overcoming
only makes you all the more able to meet the next
tough one.

You cannot win liy lieing asleep
to your opjMjrtunities and possil)ili-
ties. No one is going out of his
way to boost you. You must boost
yourself by seeing your chances
when they come along, and taking
advantage of them.

,\iid, Inially, unles'^ yon are
]ihysically and mentally fit to do
the best that Is in you, you are not
])laying fair to yourself or to your
team

Trulv. it would be a fine thing
if more of us had the atlvantagcs of
a fftotball training.

910

POWER

December 19, 1911

Isolated Power for Making Shoes

The newly finished shoe factory of the
Julius Grossman Company, DeKalb
avenue and Steuben street, Brooklyn,
N. Y., is an example of a modern iso-
lated-plant equipment for factory pur-
poses. The company found its facilities
limited in the crowded section of New
Yorlc City. The plant is designed on
modern lines conducive to economy in
operating costs and overhead charges,
and at the same time provides for the
comfort and safety of the employees.

Factory Building

The main factory building is 200 feet
long and 60 feet wide and the extensions
for elevator, toilets and stairways are
20x42 feet each. There is one return
extension of the main factory building
30x40 feet, and five stories in hight; the
boiler room is 20x42 feet and is one
story in hight. The main building is of
mill construction with 80 per cent, win-
dow exposure. The halls, main stair-
ways, elevator and toilets, also an in-
closed fire-escape tower, are all outside
of the building proper on an adjoining
alleyway, leaving each floor unobstructed
for light and ventilation.

A sprinkler system has been installed
throughout the building, and is connected
to a 25,000-gallon water tank which is

By W. B. Wilkinson

The machinery in this
plant is driven by motors
suspended from the ceilings.

Electrical energy is ob-
tained from two direct-
current generators, belt-
driven from, a line shaft.

Powerissuppliedbya Cor-
liss engine taking steam from
tivo return -tubular boilers.

BoiLER-Roo.M Equipment

The power-plant equipment consists of
two 125-horsepower horizontal return-
tubular boilers. Fig. 2, built to carry 125
pounds \vorking pressure per square inch.
Each furnace is equipped with dumping
grates and an auxiliary steam-jet blower
to assist in burning low-grade coal and
the factory refuse. The boilers are sit-
uated in a boiler house adjoining the
main building and the boiler room is con-
nected with the engine room, which is on
a level with the basement floor. A twin-
breeching and smoke-flue connection

to be used as an auxiliary feed to the
boilers. Safety water columns with high-
and low-alarm whistles are also provided.
All drips are connected under the floor to
sewer drains.

The underwriters' fire pump is also lo-
cated in the boiler room with the hose
coil, and a hose house is built on the
roof of the boiler house.

Engine-room Equipment

Adjoining the boiler room, but in the
main building, is a large, well lighted en-
gine room. Fig. I. A 14x36-inch, 125-
horsepower Corliss engine, with a 10-
foot flywheel of 22-inch face, rests on a
solid concrete foundation, which extends
5 feet below the floor and 12 inches above
the floor level. The engine is set at one
side of the room and drives a 3l,*-inch
shaft by means of a double belt which
runs on a 54x24-inch split pulley placed
20 feet between centers. The steam
pressure is 90 pounds per square inch
and the engine speed is 100 revolutions per
minute. A steam separator is attached
to the steam line just above the engine
cylinder.

Two three-wire generators are attached
with double belts on pulleys having 10-
foot centers. The machines are of 50

Fic. 1. Corliss Engine and Generating Equipment of Plant

located on the roof and supported by a
steel framework. A blower system re-
moves all dust from the machines in
the factory to a receiver on the roof,
from which it is conveyed to the coal
vaults in front of the boilers, the refuse
being mixed with the coal and burned as
fuel.

Modem plumbing has been installed
in large separate toilet rooms on each
floor, with sanitary walls and floors. A
house-supply tank for the toilets is placed
on the roof. The elevator and fire-es-
cape towers also open on the roof.

which is lined with fire tile leads to a
brick stack from the boilers; an auto-
matic hydraulic damper regulator regu-
lates the draft. Surface Mowoff connec-
tions are joined to the blowoff tank, which
is set on cast-iron cradles. The blowoff
pipe in each combustion chamber is pro-
tected by an asbestos covering. A non-
return valve is placed on the steam dome
of each boiler for emergency use in case
of rupture to a steam pipe or fitting, etc.
All high-pressure piping and fittings are
extra heavy.
An injector is placed in the boiler room

and 75 kilowatts capacity, each running
at 430 revolutions per minute.

From each machine, generator cables
are connected to a specially designed
switchboard, from which power cit'cuits
at 220 volts and lighting circuits at 1 10
volts are carried in iron conduits to panel
boxes placed on each floor of the build-
ing. From cutouts in these boxes power
lines are carried to the rheostat panels
which control the speed of the motors
which are suspended from the ceilings
of the various rooms.

Separate lighting circuits are provided

December 19. 191 1

P O V(' E R

911

for 100-watt tungsten lamps for the cen-
ter illumination on each floor, for 16-
candlepower lamps at each machine and
for lighting the toilets, stairways, ele-
vator, etc. The lighting circuits are all
controlled from the panel boxes, to which
access is had only by an authorized per-
son. A separate power circuit for the

vacuum pump with an overhead receiv-
ing tank are installed on concrete founda-
tions above the floor level. They are
shown in Fig. 3.

The exhaust line from the engine is
carried to the top of the building. A
back-pressure valve is located at the ceil-
ing and an exhaust head on the exhaust

chines and the heating system are car-
ried down to the receiving tank and
heater through the oil separator, and all
high- and low-pressure returns are prop-
erly trapped.

A plan view of the power plant, show-
ing the general arrangement of the ma-
chinery, is illustrated in Fig. 4.

Fig. 2. The Boiler Room

Fig. 3. Pumping Equipment

elevator is carried in an iron conduit from
the switchboard to the elevator shaft and
through it up to the controller box on
the roof.

Switchboard

The slate switchboard consists of three
panels, one instrument panel for each
generator, upon each of which are mounted
two ammeters and a voltmeter, five-pole
circuit breakers, ground detectors and
pilot lights, and the distributing panel
upon which are mounted separate five-
pole switches for power and lighting cir-
cuits, also an elevator switch, and a sep-
arate switch for the basement lights.

All the machinery in the plant is motor
driven except the heavy machinery in
the basement, which is driven from a
countershaft in the engine room. This
shaft has a double-quill cutout, so that
either generator can be thrown in or out
at will.

Auxiliaries

An open-type feed-water heater stands
on a concrete foundation above the level
of the engine-room floor. Connections
are made by means of a three-way valve
to the feed and exhaust lines. This
heater combines a water purifier and oil
separator and the water level is auto-
matically machined by means of a ball
float, and sustains a feed-wafer tempera-
ture of 208 to 212 degrees Fahrenheit.

Pi'.MPS

There are two fi and 4 by 6 duplex
botlcr-feed pumps controlled by a special
Kitts pump governor: a separate steam
pump for the house-service tank and a

end above the roof. A live-steam line is
carried to the top floor and is connected
by a reducing valve to the exhaust line;
it has connections on each floor for
machine use. From the exhaust line on
the top floor the heating mains are taken,
being designed for a gravity and vac-
uum combined system of heating. The

From cost records of the coal and water
consumption used in developing power,
together with the maintenance charges, an
efficient showing has been made. The
coal consumption averages 25 pounds of
coal per day of 10 hours per operating
horsepower, and the cost of electric cur-
rent figures less than 3 cents per kilo-

^^^

Plan of Boiler and Engine Rooms

wall coils extend the entire length and
breadth of each floor, and radiators arc
placed in the office and halls. The con-
tinuous wall radiators in all toilet rooms
are connected with impulse and difTcr-
ential valves, insuring a uniform tem-
perature of 70 decrees on each floor.
All drip lines from exhaust heads, ma-

watt-hour, a practical demonstration that
manufacturing plants of this type can be
operated more economically than if cen-
tral-station scnice were used.

The power-plant equipment and elec-
trical installation were plar-'cd and in-
stalled by the Wilkinson Steam Engineer-
ing Company.

POWER

December 19, 1911

Cost of Power in New England Mills

Early in 1907 the Fitchburg Yarn Com-
pany had to face the problem of either
meeting the outlay of building a power
plant of its own or purchasing electric
power from outside. The best electric-
power transmission offer was in the
neighborhood of $30 per Icilowatt deliv-
ered on the switchboard in the mill. The
general manager, George P. Grant, Jr.,
believed he could do better than this, and
he also recognized that some steam plant
would be required anyway to do the heat-
ing and to supply the steam for condi-
tioning yarn, etc., the investment for
which by itself would be considerable,
while in conjunction with a central oper-
ating plant for power it would be of slight
account.

F. P. Sheldon & Sons, of Providence,
R. I., consulting engineers, who had also
designed a notably economical plant for
the Warren Manufacturing Company, were
therefore authorized to draw up plans
and specifications for a suitable plant.

It was not until some time later in the
spring of 1910 that a careful record of
all costs against the steam plant was
kept, and the following data are fur-
nished by Raymond L. Foster, the chief
engineer, who states that the average
horsepower is taken every week from two
sets of indicator cards for the period of
a full year's run, ending March 25, 1911.
The minimum diagram taken during the
year showed 1291.83 indicated horse-
power, and the maximum 2107.79 indi-
cated horsepower.

I'OWrCR ri ANT (I1-' FITCHBURG YARN
COMI'A.W I "l; llli; YEAR ENDING
M \i:i 'I I ■_'."., Kill
Hewes & I'liilhi.- . j ..~- K.mpoiind Corliss en-
gine, 26 uinl ."ii; by ^M inches :
lioller pressure per square

iuc'li

i lb.

Ho

Recoiver pressure per

scpi.Tie inch 19 lb.

res & rhillii)s independent driven venturi

.'i I'illon's Manning type boilers, 74-inch waist,
IT !.">! tubes :

<;,-A\r iu-ea 102.40 sq.ft.

II. MiiiiK surface 10.449 sq.ft.

Sni>' 1 licating surface 4.(')a2 sq.ft.

1 I; li.ivis (ileaner exhaust heater:

WmIit from 44° to 118°

I. r. I>a\is Gleaner heater:

t'.xiiausi of conden.sing engine
and condensation from re-
ceiver, water from 118° to 152°

•Green V\ie\ Economizer, 4488 square feet
heating surface:

W.'itiT frnin 152° to 232°

<:i '■ 't till; economizer... 430°

i:i ' II iiiL' cliimnev 230°

llulii ..I , lii[iiue.v 16.")'

Williiim A. .K ('^'»u coal, semi-bituminous:

t;o.st of coal per ton .$4.30

A\erage Indicated horsepower... 1,744.28

COST OF rOWICR
4229.57 pounds coal per horse-
power (Including banking and

heating) $8.46

1 .abor 2.92

Supplies and repairs l.n

Total operating expenses

Hcpreclation and interest $4.01

Taxes 0.72

Insurance 0.04

Total (ixed charges.

By H. G. Brinckerhofft

A careful record of all
costs against the steam plant
showed that power was gen-
erated for $ 1 6.68 per horse-
power-year, %vhich in this
particular plant meant an
annual saving of $10,000
over the price offered for
electric power without mak-
ing any allowance for the
heating.

•Cop.vrigbted. 1911, b.v thg Green Fuel
Economizer Company.

tNew England manager, the Green Fuel
Economizer Company.

It may be pointed out here that the
inland location and altitude are against
this plant for economical results com-
pared with places like New Bedford, Fall
River, Providence, Warren, R. I., and
other seaboard towns which are favored
with a cooler and more plentiful supply
of injection water for condensing in sum-
mer, as these places, being at sea level,
should give them the best vacuum, while
the altitude at the plant in Fitchburg is
about 480 feet, and the water for con-
densing runs as high as 108 degrees in
summer. Nevertheless, in spite of such
adverse conditions in the location, from
the foregoing exhibit the saving secured
in the adoption of a power plant of its
own by the Fitchburg Yarn Company
works out as follows:

One kilowatt at S30 is equivalent to
S22.50 cost per horsepower.
$22.50 — 816.68 X 1774.28 horsepower
= $10,151.70
The above amount therefore is the saving
on its cost for power over the offered price
for electric power by other parties. Even
on the gross cost at $17.26 it would show
$9140.02 saving per year over buying
power, and besides getting all heating.

In the above calculation of difference
of cost no reckoning is attempted to in-
clude the cost for the electrical power
which would have been paid from the
switchboard record for all the electrical
losses in the motors and wiring beyond

$12 49 'The size of the Green fuel economizer has

since been Increased.

tCorrected to tho standard basis of coal at

.S4 per ton, the cost would be $13.74. or

$0.0053 per horsepower-hour, equivalent to

4.77 .$0.0073 per kilowatt-hour. The Warren Man-

ufacturing Company, which is a larger plant

$17.26 on the same basis and adjusted to the same
0.58 number of hovu's per year, showed a cost of
$14.57 per horsejiower, or $0.0031 per horse-
power-hour, equivalent to $0.0068 per kilo-
$16.68 watt-hour.

that point, which the mill would have had
to stand, and which Mr. Sheldon esti-
mates would have increased the amount
to be paid for such electrical power by at
least 12 per cent., although 18 per cent,
is nearer the results obtained in practice.

To make the situation truly compar-
ative to the case of purchasing outside
electric power, the expense for building
and maintaining a special heating plant
"would further augment the advantage of
saving shown by the central power plant.
Mr. Sheldon writes in regard to this:

"I should estimate the cost for the
necessary boilers, piping, covering, build-
ing, pumps, chimneys, etc., for a steam-
heating plant only to be about S9000, em-
ploying the same method of heating as
now, and the cost of doing the heating, if
the same method is used as now, ought
to be the same as it is now. I can see
no reason why it should not be the same,
and on the S9000 item I should estimate
for interest and depreciation, 10 per
cent."

It is obvious that the labor costs of a
heating plant only would be greater than
when had in connection with a central
plant, which would make such data a
matter of judgment to dissect from its
inclusive cost in the above. Therefore,
on some closer basis of offering for elec-
trical power any interested party could
as competently calculate more exactly the
comparative cost of the independent-
power advantage to a closer and more
profitable basis. The writer does not be-
lieve that anything would be gained to
further work these data out here, as the
exhibit is comprehensive as shown. The
object of the paper is to develop the nor-
mal cost for factory steam power for its
complete operation, and not an attack on
electrical transmission.

It is worth noting that there are no
"frills" to the equipment. The engines,
boilers, heaters and economizers are
standard designed goods, such as are
found in the usual run of modern mills,
and hence the result may be accepted as
a fair showing of what any similarly
equipped mill might readily equal.

No attempt was made to scrimp on
supplies, inferior labor or care, to make
a fancy showing. Everything necessary
in these respects to assure reliability of
operation within the limits of ordinary
prudence and wise economy is the policy
of the management, and can be compre-
hended by the fact that the mill has suf-
fered no losses from shutdowns of the
power plant, operating continuously 56
hours a week, except for six holidays.

Quite probably the repair item may
grow somewhat larger outside of re-
newals that may be properly charged to
depreciation. But even so, allowing 60
cents per horsepower additional, 'vhich

December 19, 1911

POWER

913

with the depreciation ought to maintain
the plant in top-notch condition, brings
the cost up to only S17.28.

As a more probable happening, with
the development of the business, and it
is growing very rapidly, the costs will
tend to fall markedly, and were another
500 to 600 horsepower added, the plant
would easily show as low as S15 per
horsepower actual total yearly cost.

It may be noticed that the final tem-
perature leaving the auxiliary is 152 de-
grees. This was the result of Sheldon &
Sons' intention, by installing power-

driven pumps and an economical type of
Corliss valve condenser, to keep down
the steam consumption and not to manu-
facture an expensive byproduct of ex-
haust steam that could be only partially
regained in the feed water, recognizing
that a proper source for heating the feed
water exists in the recovery of heat going
up chimney. Just as the Gleaner heaters
are accomplishing all they can do and
were expected to do, so the Green econ-
omizer is seen to be doing likewise, with
a low flue-gas temperature entering at
only 430 degrees. Although the showing

on the heaters and economizer is con-
siderably reduced in the exhibit for the
year's average, caused by fluctuations of
over 800 horsepower in operating, making
conditions for thefr proper showing below
normal for their ability, yet for neither
class of feed-water heaters were exces-
sive wastes manufactured for the benefit
of having these heaters make a superior
showing. The general layout shows a
simple, well designed plant, purposed to
avoid all sources of waste. Its economy
is remarkably good for a plant not ex-
ceeding 2000 horsepower in capacity.

Davies' Ex

A short while before Davies suc-
cumbed to the dreaded derangement of
mind which now closely confines him to
an asylum, he recounted to me the in-
cidents of the tragedy in which he in-
curred the terrible scars that so com-
pletely disfigured his face and hands. I
was the more surprised at the recital as,
hitherto, he had been most reticent con-
cerning what we, his friends, had always
believed to be the result of an accident.
We had never questioned him for we re-
spected his evident desire not to speak
of it. and we carefully refrained from
adding to that sorrow which we knew to
be burdening iiis mind.

It was upon a Sunday evening, when
he and I were enjoying our after-supper
pipes, seated in comfortable chairs on the
veranda, that he related the incidents of
the occurrence.

"Twenty years ago, I was a fireman in
one of the many engine houses dotting
the slate quarries of a town in north
Wales. I had two boilers to operate, but
the old engine demanded but little steam
and my position was pleasant enough. 1
had bright prospects of succeeding my
old chief and then having and enjoying
a home of my own. But before these
ambitions were realized our native quarry
manager was superseded by an English-
man who believed in nothing that was
not English. I, therefore, was not sur-
prised when a burly six-foot Englishman
took charge of our engine house on the
retirement of the chief. What part of
England this man came from I was never
able to discover and it is well that I did
not. as later events will show. His pre-
ceding job must have been close to a
tavern for, surely, no man in his leisure
hours only could learn to dispose of the
quantity of Intoxicants to which the
empty bottles bore daily witness. He
left to me the whole care of the station
and as long as nothing untoward hap-
pened I felt no alarm for the plant; I
had the time to do his small share of the
work as well as my own.

"But—" and here Davies took off and
wiped the colored spectacles which he
wore — "but it is the unexpected that will

p e r 1 e n c e,

By R. O. Richards

While draiiing the fires,
because of sudden loiv li'at-
er, Daines, the fireman, is
struck down by his drink-
crazed chief. He falls
among the uhite-hot coals
and is fearfully burned.

There's a moral.

happen some day in every plant, and hap-
pen it did in ours. It was about two
o'clock one afternoon when I noticed the
water lowering in the gage glass of each
boiler. I hastened to the pump expect-
ing to see it stopped, but found it run-
ning much faster than usual. A valve
gone, I thought, for valves had caused

a Tragedy

We had another, but it was out of com-
mission for want of plunger packing,
requisition for which had been in the
hands cf the chief a month previously.

"After half an hour, during which time
I had tried every expedient at my com-
mand to increase the volume of water In
the boilers, I commenced to feel real
alarm, for instead of rising the water was
steadily lowering so that now It stood
within half an inch of disappearing.

"Clearly something had to be done,
and that quickly, but why should I take
the responsibility of shutting down the
plant? Was not the chief there for that
purpose? Drunk or not drunk, I would
compel him to shut down the engine, even
if I had to prop him up by the throttle.
But a glance at the sodden figure huddled
in the engine-room chair convinced me
that no aid could be expected from him.

He and ! Were En.ioyinc Our After-supper Pipes

the only trouble I had ever experienced
«ith this pump. Expecting to obtain suf-
ficient water in the boilers to effect a
hurried repair, I speeded up the pump.

Had I time to replace that defective valve
before that half inch of water disap-
peared in those glasses? Surclv. the
worst that could happen is a shutdown.

ii|4

whicli seemed inevitable, unless I risked
the repair. Without wasting another
monient, after quicltly starting the idle
pump which I hoped would throw some
water if allowed to race, I commenced
tugging desperately at the nuts on the
valve chest of the other. Oh, why had
I drawn them up so tightly? Surely that
old piece of canvas which I had white-
leaded and used for a gasket in lieu of
something better did not require the nuts
to be drawn up so tightly as this. A
stud broken! I hope I do not break any
more. Such were my comments as I
labored to clear that valve-chest cover
only to find when it was removed that
both sets of valves were intact. Clearly
then it must be the plunger packing and
there was not an inch anywhere in the
plant!

"I arose from my stooping posture
with a bitter smile, and clenching my
fist I shook it in the direction of that
English manager's office. 'Now,' I ex-
claimed,' 'what do you think of your d

Sassenach, drowned in your English ale.
^°u .' but the necessity of quick ac-
tion withheld me.

"The old pump clattering in the cor-
ner had done well, for there was a
quarter inch of water still visible in each
glass. It was apparent, however, that
the engine must be stopped immediately
and the fires hauled out.

"Determined that the chief should take
the responsibility of shutting down the
engine, I proceeded to the engine room
and, knowing that verbal persuasion
would prove ineffective, I vigorously
shook him— shook him until his teeth
rattled, for now my Celtic blood was
aroused. Hauling him to his feet, and
alternately pushing and pulling, I stood
him up in front of the throttle and
bade him close it. But there he must
have collapsed, for when I returned to
the engine room after drawing out the
fire under one boiler, I found him huddled
in a heap on the fioor. Hastily picking
up a bucket I filled it with cold water
and doused him with the contents. He
blinked, coughed and spat, but finally
he sat up with a gleam of understanding
of what I was profanely bellowing at
him. Satisfied that he understood, I re-
turned to the boiler room and commenced
hauling the fire from under the other
boiler.

"As I bent to the work I was annoyed
by water dripping from the roof. At first
I took no notice of it, but the persistence
wjth which it dropped on my bare head
caused me to stop and look through the
open window, curious to know if it was
raining. 'It is not raining; where is that
"■ater coming from?' I questioned. Like
■a flash the cause of the leakage almost
overwhelmed me. Calling mvself all the
ools names that my own and the Eng-
lish language contained, I ran for the
engme room. The chief was standing
by the throttle, unsteadily closing it Ex-

POWER

citedly I swept him aside, and with strong
sweeps opened it again, while I yelled,
'The heater, the heater!' 1 pushed him'
aside quite roughly and he lay sprawled
on the fioor. Stooping down beside him
with slow emphasis, that each word might
pierce the thick fog of his befuddled un-
derstanding, I cried, 'Don't stop the en-
gine; you have a split tube in the heater!'
And I pointed to the huge upright affair
that stood on the same level as the en-
gine, but towered five feet above the
cylinder.

"Not wishing to take any chances with'
him, however, I hurried .back to the
boiler room, opened the heater drip and
stopped the pump. There now remained
but to pull out the rest of the fire and
explain matters to the irate manager
when he appeared. I had about accom-
plished the hot work of drawing out the
fires, when the light from our only win-
dow became partially obscured by a
shadow. Before I could look up, I re-
ceived a blow on the head with some
object— an empty bottle they afterward
told me. Stunned, I pitched head first
and face downward into the midst of that
ton of white-hot coal, that had almost
baked me even to draw it out.

"My God! the memory of it even now
unmans me!" and Davies again took
off those ugly spectacles, but, now, it
was to wipe away the tears which sud-
denly welled at the poignant recollection
of his awful experience.

"Say no more about it, Davies," said
I; "let it go at that," for I was becom-
ing affected myself.

"There is not much more to tell," he
continued. "When I came to at the' hos-
pital I related the incidents to some of
my friends, who had anxiously gathered
around my cot. Early next morning, it
is said, a dozen picked men — men from
whom the wild and the reckless had been
eliminated — a dozen jurymen capable
of strict justice, but jurymen also de-
termined to personally execute their
verdict, lined the narrow pathway leading
to the engine house. But they waited
in vain for the culprit; during the night
he had vanished.

"When I got well I thankfully received
the money which my fellow-workmen so
kmdly i;ollected for me, and with it pur-
chased a passage for this countr>'. I was
off'ered the position of chief at the old
place, but I crossed over here to avoid
embarrassing the woman I loved, and to
escape that awful passion which would
drive me to hunt that man and kill him."

December 19. 191 1

First Western Built Auto-
matic Engine

"So far as I have been able to learn,"
said Orosco C. Woolson, of New Yoi^k
City, to a Power representative recently,
"I believe I am entitled to the distinction
of having erected and run the first West-
ern-built automatic cutoff' engine ever
set up west of the Alleghany mountains."
Believing that its description and early
history would be of interest to Povfer
readers, the interviewer induced Mr.
Woolson to talk of his pioneer labors in
automatic steam-engine work. He said:
"The engine was built in Ohio and set
up in Chicago in I87I-2. In these
days it would not be considered a very
big engine, yet at that time it was larger
than most horizontal semi-high-speed en-
gines found in the country milling dis-
tricts. I understand that they started build-
ing the Buckeye engine about this time,
and I saw what was said to be the first
on the cars after I had set up the Chicago
engine.

"I do not now remember the
exact dimensions of the cylinder of
this Chicago engine but it was rated
at 200 horsepower. The bed was of
the Porter-Allen pattern, with an over-
hang cylinder supported at its outer
end upon a cast-iron pedestal, but not
bolted thereto. The automatic valve gear
was built from the patents of two of the
finest men this country has ever pro-
duced.

The fund left by the late George M
Pullman for a free school of m'anual
framing at Pullman, 111., has recently
been increased to over $2,500,000. A
site has been purchased, and Prof L G
Weld, the dean of the school, is visiting
schools throughout this country and
turope in preparation for the definite
planning of the new school.

Babcock & W1LC0.X Valve Gear
"Doubtless there are many who do not
recall this valve gear of Messrs. Babcock
and Wilcox, and many of the present
generation who are ignorant that there
ever was such a valve gear. The name
Babcock & Wilcox has been so intimately
associated with steam boilers the past
forty-odd years that it may seem to them
that It was always boilers. There was a
time, however, when Mr. Babcock and
his partner were devoting much time and
money to their engine, which promised
to become a potent factor in steam-power
equipment.

"Some may recall the eff'ort made by
these gentlemen, back in the sixties, at
the old American Institute on Third
avenue, in this city, to exhibit the work-
ing of their cutoff mechanism within the
steam chest. They substituted for the
large cast-iron steam-chest cover a cast-
iron frame with heavy clear-glass panels.
This was more successful in stand-
ing the pressure than might be supposed
but great care was necessar^■ in bolting
up as well as in heating up. So far
however, as affording a view of the in-
terior working parts of the cutoff was
concerned: it was practicallv a failure
due to almost continual condensation-
and it was only at intenals that any
moving part could be seen in motion. The
cracking of the glass panels finally com-

December 19, 191 1

POWER

915

palled their removal and replacing the
original cover.

"I do not know of any engines now be-
ing built with a similar cutolT. To describe
its character is simple enough, but to
understand it without drawings may not
be as simple to understand. One fea-
ture of the design of this Babcock &
Wilcox engine was the large steam chest,
extending the whole length of the cylin-
der and nearly as wide as the diameter
of the cylinder. Within this chest was
a large box valve, on the back of which
were located two cutoff riders, placed one
at each end, as nearly over the main
steam ports as was possible, to reduce
the clearance to a minimum. Midway
between these riders or cutoff plates,
upon the box valve, a small steam cyl-
inder was located with its double-ended
piston rod extending each way to the
cutoff plates. To the rear cutoff plate
was connected another rod extending out

through a stuffing box at the outer end
of the steam chest.

"This telltale rod, of I. ^ -inch steel,
was the only tangible connection between
the inside mechanism and the outside
world except the oscillating rod which
actuated the cutoff-cylinder valve. As
this oscillator was controlled by the en-
gine governor it timed the throw of the
cutoff plates. This mechanism and its
connections were very ingenious, and if
the efforts of jMessrs. Babcock and Wil-
cox had succeeded in making the work-
ing mechanism show through the glass
steam-chest cover, it would have created
great interest and enthusiasm.

"The engine gave an excellent diagram
when working normally. While it was a
simple matter to screw up the stuffing-
box gland too tight at the telltale rod at
the rear or tr>' to start off with the
tallow in the packing a little too cold
I thus freezing this rod and preventing the

cutoff plates throwing at all, or at other
times sluggishly), still, after this idio-
syncrasy was made plain, but little
trouble was experienced.

"No, I did not continue in engine work.
I have given more attention and study
the past 20 years to combustion and spe-
cial furnace work as being of more im-
portance, possibly from the same reason-
ing that Messrs. Babcock and Wilcox
abandoned engine for boiler construc-
tion. To them the boiler was of greater
importance.

"When it comes to these two problems
of the boiler and the furnace, the boiler
must wait on the furnace; a furnace can
be run forever without a boiler, but a
boiler cannot be run for an instant with-
out a furnace. From my way of reason-
ing, the furnace has the big end of the
whip, but it makes a vast difference what
is the character of that whip."

Is Peat an Important Fuel in the U.S.?

If the question is asked for the entire
country and for the immediate present,
only a negative answer can be given by
even the most optimistic.

On the other hand, one has but to
glance at a map showing the distribution
of the regions of abundant workable peat
deposits in the United States to see that
they lie alrnost entirely outside of the
coalfields of the country. Moreover, they
are found in districts where much fuel
is required and where fuel of ever>' kind
is constantly growing more costly as
economic conditions change, demands on
the diminishing supplies of wood, coal
and other fuel supplies become more
insistent, and transportation and handling
charges become higher.

The total area of peat beds in this
region which have sufficient size, depth
and purity to be attractive for commercial
exploitation, has been conservatively es-
timated at approximately 11,200 square
miles; these beds, in round numbers,
contain at least 13 billion tons of salable
fuel. There is probably an equal or
greater area of small peat deposits, with,
at tlie least estimate, an equal possible
tonnage, which could be worked for fuel
by individuals or small communities but
might not be attractive for larger in-
vestors.

This estimated tonnage would supply
the entire country with fuel for many
years if used at a rate equivalent to the
present rate of coal production. If used
only in the parts of the country where
it occurs, it is obvious that the useful
life of the resources would be much pro-
longed, as well as that of the fuels which
would be displaced.

When properly prepared and used in
correctly designed fireboxes, peat is a

By Charles A. Davis

// /.f estimated that there
are 1 1 ,200 square miles of
peat beds in this country,
containing 13 billion tons
of salable coal.

The best peats run as
high as 11,000 B.t.u per
pound.

Most jailures are attribut-
ed to ilie inexperience or
ignorance of those having
peat development in charge.

•.M.stin.l •.< pnp.T iT-ntl nl .-l in. -..tine cif the
.N.w York s.MllMii .,f tlip Amoiic:in lli.'mlrnl
.Si.clpty. by iiPimliislon of the lilreitor of tli»
Huraii of Mines.

fairly good fuel, the best grades, on the
theoretically dry basis, exceeding in ther-
mal value many lignites and some'of the
poorer grades of coal. The best peals
may run as high as 11.000 B.t.u. per
pound, but those giving from 8(XX) to
9000 B.t.u. are much more common, just
as medium-grade coals are more com-
mon than those of highest calorific value.

Not on a Commercial Basis

Although peat has been used as do-
mestic fuel in Europe for many years,
and there has been a marked increase
in its use for power production in Swe-
den. Russia and Germany during the
past decade, it has never been produced
on what could be termed a commercial
basis in the United Stales. For this rea-

son it has frequently been said by Ameri-
can writers that other and better types
of fuel were so abundant and cheap in
this country that there was no place for
peat, when, as a matter of fact, in at
least some of those parts of the United
States where peat is of frequent occur-
rence, coal sells at considerably higher
prices than good English coal can be had
in some of the peat-consuming countries
of Europe.

Such writers also point out that, in
spite of the large sums of money spent
in establishing peat-fuel factories in the
United States, no peat fuel has been
put on the market, and therefore they
say that peat fuel is a failure here. As
a matter of fact, however, a careful
analysis of the attempted manufacture
of peat fuel in the United States shows
that other causes than qualities inherent
in the peat have been operative to pre-
vent the success of the factories men-
tioned, and that every pound of the fuel
which they have made could have been
or has been sold; in fact, much more
has been called for than could be de-
livered. The causes of failure have been
such as beset all new and untried in-
dustries, and most of them could be di-
rectly traced to the inexperience, the
optimism and, too often, to the ignorance
of those having the developments in
charge. The experience of European ex-
perimenters and manufacturers has been
passed lightlv by as nni applicable to
our conditions or often has been entirely
ignored, and untried machines and pro-
cesses substituted for those of proved
worth. Not infrequently purely visionar>'
plans and machincr>'. based on entirely
wrong conceptions of the properties of
peat, have been made the basis of the
enthusiastic promotion and consiruciion

)16

POWER

December 19, 1911

of costly plants which from their incep-
tion never had a chance to successfully
produce peat fuel on a commercial scale.

Its High Water Content

The greatest practical difficulty in pre-
paring peat for fuel lies in its high water
content, which may exceed 90 per cent.,
as it lies in the bog, and rarely, even
in drained bogs, is lower than 80 per
cent. After trying and abandoning many
devices for pressing the water from peat,
for treating it by heat, both directly and
by superheated steam and by electricity,
to remove the excess of water, European
peat- fuel producers have now come to
rely almost wholly upon the sun's heat
for drying their product. The raw peat,
wet as it comes from the bog, is thor-
oughly pulped or ground in simple ma-
chines and either formed into bricks
which are removed from the machine
and laid out to dry on pallets or, by the
most recent practice, the macerated, wet
peat is spread by the use of a simple
spreading device into a thin sheet on the
roughly prepared surface of the bog, as
near as possible to the excavating pits.
The same machine which spreads the
pulp also cuts it up into brick-shaped
pieces, which, when dry enough, are
turned and still later are piled up in
small open heaps, and, when they have
dried sufficiently, they are stacked under
sheds or in loosely piled stacks to com-
plete the drying process.

It has generally been assumed by
American experimenters that such a
method of procedure was not adapted to
labor conditions existing in the United
States; hence no serious attempt has
been made in the country to establish
a peat-fuel factory of this kind to learn
if it could be made profitable here. In
Canada, however, the Mines Branch of
the Dominion Department of Mines, after
careful preliminary investigation, estab-
lished in 1909 a peat-fuel plant for
demonstration purposes. It was equipped
with machinery that had been thoroughly
tested by continued commercial success,
imported from Sweden, and the entire
operation of the plant was placed in
charge of a well trained and experienced
man. The work at this factory was car-
ried on by laborers hired in the neigh-
borhood of the plant, who were paid
about the same wages that would be had
in the United States for similar work.
The capacity of the plant was rated at
30 tons per day of salable product. The
output for the first short season's run
was given as 1000 tons and the average
cost of production based on this and all
charges included, according to official
figures, was SI. 65 per ton loaded on the
cars, of which only about .$1 was for
actual production. This price, it is stated,
could be reduced by the use of mechan-
ical diggers, already perfected, in place
of hand digging, which was used.

Calorific Value

Peat fuel made by this method has a
calorific value considerably greater than
half that of good bituminous coal and
is a more acceptable fuel than coal to
many people for cooking and other do-
mestic purposes; in properly constructed
fireboxes it is excellent for steam produc-
tion. It was estimated by the Canadian
authorities that the equivalent of a ton
of anthracite costing in Ottawa 87.50
could be made ready for use for less
than $3.

As to the possible use of peat fuel of
this type for power generation, it is an
old story that several industries, notably
cotton factories, in Russia for years have
been using peat fuel for generating
steam; it is also reported that this use
increases at the rate of about 200,000
tons a year. In Germany and Sweden
also there is a growing use of this fuel
for power production, kiln firing and
foundry work.

A Good Fuel for Gas Production

The most recent advances in utiliz-
ing peat for fuel, however, have been
made by its use in the gas producer for
generating power and fuel gas. It has
been established beyond question by ex-
periments by the United States Geolog-
ical Survey, by the Canadian Department
of Mines and by successful commercial-
ly operated plants in Sweden, Germany
and other countries of Europe that air-
dried peat is a good fuel for gas produc-
tion. In some makes of producers de-
signed for the purpose, peat is now gasi-
fied and made to furnish a clean and
uniform gas of good calorific value to
gas engines, and lighting and power
plants are known in which no other fuel
than peat has been used for several
years past.

A recent report of one investigator,
who has had exceptional opportunities
for working on the subject, states that
with the type of gas producer with which
he has worked he gets a producer gas
which enters the engine entirely free
from tar and other bituminous matter,
and that the producer required no pok-
ing or other attention except when fuel
is added and the ash removed, so that
one man can attend to both the producer
and engine. The average result of test
runs with this producer was a horse-
power per hour for somewhat less than
2 pounds of dry peat fired, which is in
close accord with results obtained else-
where. The author of this report also
says that he feels justified in stating that
if peat fuel can be delivered at the pro-
ducer for S2 per ton, the cost of a horse-
power per year, in plants equipped with
gas producers and using peat fuel, should
be about S7.50.

As $2 per ton is a very conser\'ative
estimate for the production and delivery
of air-dried peat, especially if the power

plant is located near the bog, it is more
than probable that the figure given may
be diminished rather than increased in
the near future.

Recovery of Useful Compounds

The commercial recovery of useful
chemical compounds from the products
of the gasification of fuels has been so
successful that it is not remarkable when
it was found that carbonized peat was
in demand — but could not be made at a
profit unless the gaseous products of the
distillation were utilized, as they were al-
ready in the making of wood charcoal —
that practically the same processes of
recovery and purification should be used
in making peat coke as for wood carbon-
ization, and about the same series of
compounds obtained.

Furthermore, when it was found that
in many peats the percentage of com-
bined nitrogen exceeded that of other
fuels, the matter of recovering this in-
dispensable substance was taken up in
earnest and made the subject of thorough
study, especially along the lines worked
out by Mond, in connection with the gen-
eration of producer gas from coal. An-
nouncements have been made within the
past year that this matter has been
worked out so satisfactorily that three
large electric-power plants in different
European countries are now being suc-
cessfully operated by gas producers,
using peat as fuel, and recovering from
the producer-gas ammonia in the form of
sulphate in quantities sufficient to make
the entire operation very profitable; other
plants of the same or similar types are
in process of development and it is
not improbable that there may soon be
one or more of these plants in the United
States. These announcements are of
greater interest to all concerned in peat
utilization, because they positively state
that peat containing 60 or even 70 per
cent, of moisture can be utilized in the
gas producers and ^ive a satisfactory
quality of producer gas. The ordinary
type of double-zone gas producer for
bituminous fuels may be run on peat
having as much as 40 or even 45 per
cent, of moisture, but the consensus of
opinion seems to be that better results
are had when the moisture content is
below 35 per cent, and the difference be-
tween this and the figures cited above is
larger than appears at first glance; peat
can be dried quickly to 65 per cent.
moisture where it might be weeks in
reaching the air-dried state.

Considering further the use of peat
as a source of producer gas, careful com-
parison of the thermal value of the gas
derived from it, as compared with coal,
based on rather meager data, shows that
the peat gas has about the same, or a
slightly larger, number of thermal units
per cubic foot as gas generated from
coal in the same type of producer, while

December 19. 1911

POWER

917

in case of handling, quality of the ash,
clinkering, etc., peat has the advantage.
To secure the highest efficiency in scrub-
bing as well as in gasification, the pro-
ducer in which peat is to be used should
be specially designed for it, but the same
is equally true of other fuels.

Peat in the form of finely ground dried
powder has been used as fuel in Canada
and in Sweden, and carefully conducted
tests have been made in the latter coun-
try, both under government engineers
and by testing commissions appointed by
manufacturers' associations.

The reports of these tests agree that
good peat prepared and burned in this
way was very nearly as efficient, ton for

in reasonable possibilities, in the opinion
of the writer, peat is certain to be a fuel
to be considered of importance to the
parts of the United States where it is
found, and indirectly to the whole coun-
try.

Discussion

In introducing his paper, Mr. Davis
spoke of a case of which he knew where
a bed of good peat 12 feet in thickness
is being removed in order to get at an-
other product and coal is being brought
from a distance of 1000 miles to con-
duct the operation while the peat is
thrown away. In another place a bed of
excellent peat 20 feet in thickness is be-

in a gas producer and generated an
electrical horsepower with a consumption
of 4 pounds, which was not bad in view
of the fact that in addition to the 30
per cent, of ash it contained 15 per cent,
of moisture. In reply to an inquiry as
to whether centrifugal separators have
been used for the extraction of the mois-
ture, Mr. Davis replied that attempts
had been made in this direction by the
German and Swedish governments but
had not been successful. It is possible
to get about 70 per cent, of the moisture
out in this way or by pressing, but un-
less the peat is divided into a very thin
sheet under very considerable pressure
it is difficult to dry it beyond this point

Areas in whkh Areo5 in which Coo' -I'^i

Workable Peot Workobic Peat F..'-)5(A
Bcdaar* Common Beds oc^.' ^ Fif'i- --

Nor+hem Limit of Weyt^m Limit of

' ttie Arvo in which the Ar»a in which ttie

^Vot Beds Avercoe Temperoture Annwol Prwipitotion

fbr Jutj? is 7dT or mone eiceeds SO Inches

ton, as the English coal with which it
was compared, 1.2 tons of the peat equal-
ing in steam-raising efficiency a ton of
coal, the cost of the peat being 17 per
cent, less (S2.76 -t 50 cents instead of
S3.95, the cost of coal I than that of the
coal required to do the same work.

In this country efforts have been made
to eliminate the use of hand labor In
preparing peat for use In the gas pro-
ducer or for boiler firing, and these seem
now about to be crowned with success.
If they are, and if peat fuel can he de-
livered to gas producers of boiler plants
located on or near peat deposits — as has
already been done in several places in
Europe — at figures that seem quite with-

Ing covered up by the slag and ashes from
a coal-operated plant. He mentions also
another case where expensive coal was
being used in the process of digging up
good peat and throwing it away. In reply
to a question if there were considerable
peal deposits around New York City, the
lecturer replied that there were none un-
less they were to be found in the ex-
tensive salt meadows. An Inquiry in
regard to the amount nf ash brought out
the reply that good peat should contain
not over 10 per cent, and it is often
found with less than 5. In Europe it
is considered of commercial value if it
docs not run over 20. In one case peat
containing 35 per cent, of ash was used

by cither of these processes. A block
of dried peat is about as tough and hard
as a block of wood. The dr>'lng process
appears to develop the colloids which
act as a hinder. Peat can be air dried in
the United States down to from 10 to
20 per cent, according to location. In
the vicinity of New York, 20 per cent,
would be about the average.

Over 1 ' .. million acres of public land
now stand withdrawn by the Government
as being valuable for the possible de-
velopment of water power. During Oclr
bcr the United States Geological Survey
recommended the withdrawal of 54,422
acres as having power possibilities.

918

POWER

December 19, 1911

Smoke Abatement in Great Britain

The latest method of attacking the
smoke problem in England is by ar-
ranging for exhibitions of smoke-abate-
ment appliances in the larger towns and
manufacturing centers, together with con-
ferences of delegates from associations
(both municipal and voluntary) whose
express purpose is securing some diminu-
tion of the smoke nuisance.

This method of attacking the evils re-
sulting from black smoke has much to
recommend it. Doubtless, much of the
smoke produced in large towns is due
to ignorance on the part of the genera!
public and the factory owners. It is now
certain that smoke is preventable, and
v.'ith the most uptodate boiler and fur-
nace appliances, and with skilled man-
agement smokeless combustion may be
secured in nearly all manufacturing
plants without sacrifice of economy. Any
method of education which helps to ex-
tend the knowledge of the scientific prin-
ciples upon which smoke abatement is
based and of the apparatus and devices
by which these principles can be applied
in practice, is therefore of great value
in combating the smoke nuisance.

The exhibition held about a year ago
at Glasgow was most successful, with
an average attendance of over 4000 per-
sons per day. This fall, Manchester fol-
lowed the example of Glasgow, and a
very successful exhibition was held in
the City exhibition hall from Nov.
10 to 25, while a largely attended con-
ference of delegates from various so-
cieties was held on Nov. 21 and 22,
ia the Manchester town hall. An ac-
count of the addresses and papers read
at the conference and of the exhibits has
more than local interest.

Gordon Harvey, as president of the
Smoke Abatement League of Great
Britain, delivered an address in which
he stated that smoke from factory chim-
neys could be entirely stopped if the
three following conditions were fulfilled:

1. Adequate boiler power.

2. Proper appliances for stoking and
for regulating the draft.

3. Careful and constant supervision
of the boiler plant by competent men.

Doctor Des Voeux, the representative
of the London Coal Smoke Abatement
Society, fcUowed with a brief paper giv-
ing some startling facts and figures rela-
tive to the losses due to smoke. Exact
measurements prove that London's loss
of sunshine varies from 15 per cent, in
summer to 50 per cent, in winter, and it
has been estimated that the canopy of
smoke which hangs over the metropolis
costs that city £5,000,000 (about S25,-
000,000) per annum.

As regards the infiuence of black fog
on the death rate, Doctor Des Voeux
stated that in the autumn of 1909 Glas-
gow was visited by two periods of smoke

Bv John B. C. Kershaw

Report of the smoke-
abatement conference and
exhibition held at Alan-
chester, Xoz'. lo to 25.
Many papers were deliver-
ed by prominent engineers
setting forth their views as
to the best methods of smoke
prevention, and statistics
were given showing the
harmfid effects of a smoke-
laden atmosphere.

fog, each lasting several days, but sep-
arated by an interval of a few weeks.
During the first period the death rate
suddenly rose from 18 per thousand to
25 per thousand, and during the second
to 33 per thousand, although the rate in
the surrounding country was hardly
raised. It was calculated that 1063
deaths were attributable to the noxious
condition of the atmosphere.

The physical evils and destructive ef-
fects of smoke were further emphasized
by Professor Cohen and by Mr. Ruston.
The former, in an illustrated lecture up-
on "The Effects of Coal SmoI;e," gave
details of the results of numerous ob-
servations carried out at Leeds and the

fuillicT. that the atmosphere is renewfd .jO
times in 12 hours, a simple calculation shows
that five tons to the square mile is daily dis-
charged into tlie air of Leeds, and that 200
I>ounds is suspended at any moment over one
sqtiare mile.

This has Ijeen estimated I>y collecting snow
on consecutive days during clear weather, and
also rain v.-ater. From tlie latter the amount
of suspended matter, including carbon, tar
and ash, in tons per square mile per annum,
was determined at different stations, and the
results ai-e given in the accompanying tahle-
The character of the station is indicated.

The average for the whole town area
is approximately 220 tons per annum
per square mile, and this represents
wasted fuel.

Mr. Ruston's paper, "Effects of Smoke
on Vegetation." was in the nature of an
appendix to Professor Cohen's remarks,
and dealt specifically with this aspect of
the subject. He thus summarized the
deductions from his experimental ob-
servations:

1. It is possible to get a measure of the
effective damage to vegetation by smoke pol-
lution.

2. The factors in smolte pollution which
prejudicially affect vegetation are :

a. The smol:e cloud limiting the available
sunliglit.

1). The tarry matter coating the leaves and
choking the stomatic cells.

c. The presence of free acids in the air,
tending generally to lower the vitality of the
plant.

d. The effect of the free acids falling upoa
the soil and limiting the activity of the soil
organisms, principally the nutrifying or-
ganisms.

The last factor can be dealt with very ef-
fectively l)y a simple application of lime, while
the first two can lie met only by checking the

SOLID I.MPl'RITIE.S IN R.MX W.\TER (Tons per Sr>r.\RB Mile pf.r .\n-n-i-m>

.

SrsPExDED Matter

Station'

Carbon

Tar

.\sh

Total

Industrial:

180. G
211.2
87.1
99.7

100.2
9.S.0
03. 2
52.3
10.2
7.7

31.4
19.7
42.6
22.3

12.3
9.7
9.1
SO
7.4
4.0

31S.0
187. 2
202.. 5
120.6

56.9
61.7
41.7
40.3
15.4
14.0

539

Hunslet

448

Beeston Hill

332

Philosophical Hall

Residential:

Headi::gly

Arraley

Woodfiousc Moor

Kirkstall

Weetwood Lane .

Roundhav

242

ISS
169
114
100
42
25

surrounding district relative to the com-
position of soot, the amount of soot
emitted from chimneys and to the acidity
of the soot suspended in the air. His
remarks were as follows:

The first acciu-ate experiments on the qual-
ity of suspended carbon or organic matter in
the air were made by the Kte Doctor Russell
on London air, and the results showed the
following quantities for fine, dull and foggy
weather in milligrams, per 100 cubic feet:

Fine weather 0"~t

Pull weather 1 .03

Foggy weather 2.44

Experiments carried out in Ix-eds agree
very closely with these observations, being on
the average 1.2 milligrams per 100 cubic feet.
Supposing tlie soot to be uniformly distributed
to a helglit of 300 feet before lieing dispersed,
according to Dr. Angus Smith's estimate, and

output of smoke, and using every effort to
lessen the air pollution, which is the ruin
of many crops.

Two very practical papers upon steam-
boiler management were read by G. B.
Storie and James Blbby. Mr. Storie's
paper was a resume of the now general-
ly accepted scientific principles of smoke-
less combustion in steam-boiler furnaces,
and while containing nothing new was
of interest as coming from an engineer
in charge of a large steam plant. .Al-
though a firm believer in the advantages
offered by artificial draft, he is not a
supporter of the steam-jet system for
obtaining this, as the following extract
from his paper shows:

Artificial draft is independent of atmos-

December 19, 1911

POWER

pherio conditions and may be produced by
means of steam jets or by fans. Tiie former
are generally applied in the ashpit for forc-
ing in air which is made to pass upward
through the grates. It has also been used to
deliver air above the fires in the form of
finely divided streams with a view to mixing
it with the gases arising from the fuel bed.
"This system of producing draft is very costly,
as a large amount of steam is used by the
jets, and it also introduces a considerable
quantity of water which has to be heated and
carried up the chimney.

Upon the training of stokers Mr. Storie
had the following to say:

I'oking the fires is one of the principal
causes of smoke production, and although the
author is aware that there are limes when
this operation cannot be avoided when boilers
are fired by hand, it is a practice which
should be discouraged as much as possible,
as it has l)ecome almost habitual with many
firemen who have placed at their disposal
clumsy tools of varioi:s forms.

The eflFects of good and bad stoking are
often very marked. Some years ago a prize
competition in hand-firing was carried out
at Sheffield, and the difference betv/een the
host and the worst showed a gain of 22 per
cent, in evaporation and IS per cent, in boiler
ofliciency. with conditions exactly tlie same
in each case.

A number of years ago a series of trials
of Newcastle and Welsh coals were carried
out on l)ehal£ of the Admiralty by T. W. Mill-
er, and the following deductions from the re-
port tabulated by the late D. K. Clark, show
a loss of efficiency of 17 per cent, due to in-
romplete combustion :

MOKE Prevented

(^"oal p;*r Sfjuar.

Foot of c;rate

per Hour

Water Evapor-

ite<i per Square

Foot of Grate

per Hour

Water Evapor-
ated per Pound
of Coal

21.69

3 46

11 OS

xJense buoKC Produced

2.1.81

3.20

In conclusion Mr. Storie dealt with the
use of the heat, which is too often car-
ried up the chimney with the waste gases,
for preheating the air required for com-
bustion. He said:

Id ronn.v tKitler In.KtallationH, the air re-
quired for comlmmloD Ih healed 1>) the nnstc
gases after they have left the holler flnes.
The clreulallnn of the air la effected by means
of a fan plared nt the oti(4el of the economizer
rhamlier. which draws the Kases through the
tubes of a heater slttiate<l over the main Hue
at the linrk end of the boiler. The air for
combustion which Is drnv.- In'o the heater
circulates outside the lulxs lhi-o::ch which the
hot itases are passlne on their way to the
economizer. Kmm the heater the hot air Is
ronveyed In pipes to the furnace front, which
Is closed, and dampers are I1tte<l to Mliow the
nir lielnK admitted liolh atiove and bidow the
fires. The provldlnc of this hot a!r. which
nllalns a lemperaliire of aU.ut 3<)0 deerees
Fahrenheit. Insurer n si.mclently hleh tem-
perature lielnc mnlnlflined diirlnic combustion
In conjunction with an Intimate mijinre of
the eases, r have had some years* experience
with a Ixiller plant arran?e<I on this system
end the results have lieen entirely sallsfnc-
lory. f>n a carefidly conducted trial, the
holier showed an overall elDrlency of 77 per
cent, and no smoke was prrwluced.

At the Hammersmith central power station
there Is a similar arraniement to the one
Just dewrlt>ed. with the exception that an

additional heater is placed in the flue lie-
tween the economizer and the (an. If'rom this
heater the air warmed ijy the waste gases
after they have left the economizer is led lu
ducts to the heater over the main flue, to
be- further heated before entering the fur-
naces. It is claimed for this two-stage sys-
tem that the temperature of the air entering
the high-temperature heater is such that the
fail in temperature of the gases passlus
through the second heater Is greatly dimin-
ished, with the result that a higher feed-
water temperature is obtained, and the final
temperature of the gases entering the fan is
reduced to about 280 degrees I'ahicnheit.

Mr. Bibby's paper covered to some
extent the same ground and dealt largely
with the scientific principles of good com-
bustion, and the means whereby these
can be attained in actual practice. How-
ever, he took the somewhat unwise course
of upholding a special form of patented
mechanical stoker (now in use in the
Liverpool works of his firm) as the most
efficient and satisfactory mechanical
stoker on the market. The stoker was
described as follows:

In this machine the grate consists of a
numiwr of iiollow bars about 4V.. Indies wide,
which are laid side by side to make up the
grate width. The fronts of thc.«!e l>ars are
trumpet-shaped, and the portion which goes
Into the furnace is T-shaped, open at the
top. Into these liars are loosely fitted a nuni-
ber of horizontal grids, the tops of which
form the grate surface proper. A steam jet
blowing in front of each bar forces air
through at a pressure sufficient to overcome
the resistance of the fuel on the grate. The
grids are so formed as to pick up the air
forced in the bar and direct It where required
in the furnace. The liars are made to travel
to and fro in such a wa.r that the fuel Is
tarried forward, the majority of the liars
going in together and returning independently
to secure this action. At the front of the
.■"urnace Is superimposed, across the grate, a
scries of grids. These grids are stationary,
but are supplied with air from the trough
bars through an inclined scoop. Small coal
is fed onto the stationary grids from the
iiopper by means of two plungers to eaclj fur-
nace, the strokes of wlilch can |H^ separately
regulated. The fuel, as soon as It is pushed
onto the stationary grids, iM-comes heated
from the fire .In front of it; the volatile con-
stituents are driven off and Ignited through
sudiclent air lieing supplle<l throi:gh the
scoop. The fuel Is then in a coking slate
and Is slowly pushed off these stationary
grids by means of the dead fuel liehind It.
onto the moving grate, the motion of which
carries It forward.

A leading feature of the furnace Is to pro-
vide separately for the operations of coking
and of complete eombusllon. The air s|iaces
ere so proporli«)n*'d that the correct amount
ef air Is supplied for each staRe. The coked
tMcl is completely iiurned iiy the lime II
reaches the end of the liars. The (|uanllly "f
air forced Into Ih*' 1>ars and the speed of the
lars are under contrtii. anil can In- regulated
to stdl any duty up to the capacity of the
furnace.

He gave the following as the points
'"hich must be sallsHed by any good
mechanical stoker and furnace:

1. A means for regulating the coal scp.
srately to each furnace so that the lied 'if
fuel Is level transversely

2. Independent provision for lioth the cok-
ing and foil combustion processes, so thni th*
correct proportion of sir Is supplied at th'
right perlotis for these processes, and perfect
comliiisllon Is secured without requiring loo
great an excess of air.

3. The furnace should lie divided into a
numlier of sections, and each section should

. be supplied separately with the correct
amount of air for the quantity of fuel tliat
It Is Intended to burn per section, so as to
prevent short-circuiting the air.

4. The bars should be given a horizontal
motion in order to move the fuel, and the
speed should be capable of regulation to suit
variations of load and classes- of fuel.

.T. While the furnace is working there
sho;:Id lie no opportunity for air to escape
into the Tues except through the furnace. A
door sho'.rid be fitted beneath the back of the
furnace so as not to depend on the ash and
clinker in the back chamber for preventing
air being drawn in.

6. All the reduction gear should lie ma-
chine-cut and in oil-tight cases, so that Ihe
machine will work under the adverse condi-
tions found in many holier houses.

7. -Vn automatic means should bo pro-
vided for discharging the ashes which fall
through the grates.

In concluding his paper Mr. Bibby
stated:

From a largo number of careful experi-
ments it has lieen found that, as a general
ri!le, with a coking stoker of this type and
liituminous coal, the steaming capacity of
the iKiiier can lie increased abotit 20 per cent,
and the efficiency increased b.v from .5 to 10
Iier cent, over hand-firing. This result Is be-
ing obtained without smoke, and in most In-
stances firms that have adopted them have
found that they can burn cheap fuel, which
could not be used to advantage by any other
means.

Exhibition of Appliances

The exhibition of smoke-abatement ap-
pliances which had been organized by
the Manchester and District Smoke
Abatement Society, with the support of
various other societies, followed the lines
that had been found so successful at
Glasgow in 1910.

The largest number of exhibits related
to the use of gas and electricity for do-
mestic heating and cooking purposes,
the domestic chimney being now gen-
erally recognized in England, as one of
the chief contributors to Ihe smoke-laden
atmosphere of all large towns and cities.
As regards the industrial section, the
manufacturers of the well known types
of mechanical stoker were all represented.

Among the special devices shown was
Tyler's patent smoke preventer and fuel
economizer for hand-fired furnaces. This
is an apparatus which is fixed to the
front of the boiler furnace for regulating
the supply of air. both through the fire-
door and at the back of the bridge-wall
in such a way that the smoke resulting
from hand-firing is combined with vttti
air in passing over the bridge-wa'l,
thereby insuring the complete combustion
of the smoke, and effecting a saving of
fuel used.

The action of the appliance is con-
trolled by a pair of springs acting on a
horizontal oil cylinder or dashpnt. which
itself can be regulated, or timed. In per-
mit the closing of the air inlets accord-
ing to the class of fuel in use in any
particular furnace. It is arranged *n
thai only enough air is admitted to ob-
tain complete combustion of the fuel.

920

POWER

December 19. 1911

and as the green coal gradually becomes
incandescent, the admission of air is au-
tomatically decreased until the extra air
inlets are almost closed. The operation
is repeated each time the furnace is
fired, the action being started by opening
the fire-door. The apparatus is admir-
ably adapted for use on boilers of the
Lancashire and Cornish types, and a
guarantee to prevent all smoke and ef-
fect economy in fuel is given in every
case.

Many other devices of interest to steam
users were exhibited but must be passed
over for lack of space.

"Failure of a Surface Condenser

The generating equipment at the
municipal lighting plant at Fort Wayne,
Ind., consists of two 500-kilowatt ver-
tical Curtis turbines and a new 1500-
kilowatt turbine of the same type, the
latter having been recently installed.

The condensing apparatus for the new
unit consists of a large surface con-
denser having twenty-two hundred •%-
inch by 16- foot tubes through which the
cooling water circulates. This water is
obtained from a reservoir adjacent to the
plant and is forced through the con-
denser by a 12-inch volute centrifugal
pump driven by a small vertical engine.
The vacuum is maintained by an 8 and
10 by 12-inch air pump. Both air and cir-
culating pumps are located in a pit below
the condenser opposite the turbine ex-
haust-steam outlet.

Early in the evening of Sunday, Nov.
12, the new 1 500-kilowatt unit was run-
ning alone, being but partially loaded.

Fic. 2. End View, Showing Fracture in Circulating Pipe

Some difficulty was experienced in main-
taining a good vacuum. The engineer in
charge went into the pump pit to locate
the trouble. Shortly, a tremendous ex-
plosion took place at that point and the
engine room filled with steam. The
switchboard attendant shut off the tur-
bine and went into the pit to find the en-
gineer. He had been instantly killed and
lay under a section of the condenser
shell. The attendant then started up one
of the 500-kilo\vatt units and again took

Fig. 1. Result of Condenser Explosion

up the load just 12 minutes after the
explosion.

The cast-iron shell of the condenser
was broken into several sections, the top
half and that portion opposite the tur-
bine outlet being forced off into the pit
and against the station wall. In falling,
the parts struck the circulating pump,
the air pump and the adjacent piping.
The housing cf the circulating pump was
trcken off just below the flange, but it
was not otherwise injured. The valve
mechanism of the air pump was shat-
tered. All steam piping and fittings for
the air pump were demolished. Many
of the condenser tubes were bent or
dented, but the turbine was not hurt in
any way. The accompanying photo-
graphs wi!l serve to show the nature of
the damage done.

The cause of the accident is not
definitely known. It is evident that the
turbine lost its vacuum and the con-
denser received steam under considerable
pressure. Whether this was due to some
fault in the air pump or to failure else-
where cannot be determined from the
evidence and information obtainable after
the accident.

The turbine is supplied with a relief
valve from which the atmospheric ex-
haust line leads downward, then through
a butterfly valve and horizontally out of
the station. It is possible that the re-
lief valve failed to operate or that the
escaping steam forced the butterfly valve
temporarily closed.

There is little likelihood that there
was sufficient water in the exhaust line
to obstruct the free escape of the steam.

The equipment is now undergoing re-
pairs.

December 19. 191 1

POWER

Catechism of Electricity

The Nernst Lamp

1156. Are there any other forms of
incandescent lamps besides the filament
types previously described?

Yes. The one most closely related to
the filament lamp is the Nernst lamp,
shown in Fig. 389.

1157. How is the light produced?
By heating a high-resistance conductor

in very much the same way as in the
fi!aTient lamp.

Fic. 389. Nernst Lamp and Globe Re-
moved FROM Holder

1 158. What is the quality of the light
given by the Nernst lamp?

It gives a soft white light particularly
well adapted for general illumination and
decorative lighting.

1159. What are the principal parts of
a Nernst lamp?

The glower, heater, ballast and cutout.

1 1 60. What is the glower ?

The glower is the conductor which is
heated white-hot. It is shown at d
in Fig. 390.

1161. Of what is the glower made?
It is composed of earthy oxides, such

as thorium, zirconium and yttrium, mixed
with suitable binding material.

1162. How is the glower formed?

The pasty mixture of oxides and bind-
ing material is forced through a die info
the form of a small white porcelain-like
tube, ranging in outside diameter from

j'f to I*/! of an inch and in lengths of ' 't
to 1 <A inches. The tube is then baked
to make it strong mechanically, and is

finally cut to the proper length for the
voltage to be used and closed at the ends.
Platinum terminals are attached to the
ends of the glower tube, after which a
coat of oxides is put on as a protective
covering against oxidation.

1163. What is the life of the glower
of the Nernst lamp?

About 600 hours on direct current, 400
hours on alternating current of 25 cycles
and 800 hours on alternating current of
60 cycles and higher frequencies.

1164. What is the purpose of the
heater ?

To raise the temperature of the glower,
at starting, and thereby reduce its resist-
ance. At ordinary temperatures the
glower is of such high resistance that
it is practically an insulator, but the re-
sistance drops greatly when heated to a

round porcelain rod and covered with
paste. The rod is then formed into a
worm shape, and in this form is called
a "wafer" heater.

1166. What is the ballast and what
is its use?

After the temperature of the glower
is raised by the heater until its resist-
ance decreases enough to allow an ap-
preciable current to flow, the heating ef-
fect of the current causes the resistance
to continue decreasing, allowing the cur-

390. Burner of Lamp Shown in
Fig. .389

Fio. 391. Sectional Views or Lamp Holder Co:, i
Ballast

high tempcratuic. To accomplish this,
the heater is mounted close above the
glower, as shown at H in Fig. 390.

1165. How is the heater made?

Of fine platinum wire wound on a

rent to increase. When the normal op-
erating point is reached, the decrease In
resistance becomes so rapid that unless
a steadying resistance, or "ballast" as it
is called, is used In series with the

922

POWER

December 19, 1911

glower, the latter would soon burn out.
The "ballast" conductor increases in re-
sistance as its temperature increases and
thereby counteracts the decrease in the
resistance of the glower beyond the nor-
mal working point.

1167. How is the ballast made?

It consists of fine iron wire mounted
in a small glass tube about an inch in
diameter and 2 to 3 inches long, contain-

becomes energized as soon as current
begins to flow through the glower; then it
attracts the armature and opens the cir-
cuit through the heater.

1172. In what sizes are Ncrnst lamps
made?

They are rated at 66, 88, 110 or 132
watts.

1173. How much light is given by
these different sizes in comparison with

Fig. 392. Diagram of Lamp Circuits

ing hydrogen. The reason for this ar-
rangement is that the iron wire is kept
at a very high temperature and must
therefore be protected from the air to
prevent oxidation and too rapid tempera-
ture changes. The ballast tube is mounted
as shown at B, Fig. 391.

1168. Why is hydrogen gas used for
the ballast in preference to other gases?

Because it will not attack the iron and
is a very good conductor of heat.

1169. Why is iron used for the ballast
conductor?

Because it is almost the exact opposite
of the glower in temperature character-
istic; that is, its resistance rises as the
temperature is increased and at almost
the same rate as that at which the resist-
ance of the glower decreases, at tempera-
tures in the neighborhood of the operat-
ing temperature.

1170. For what purpose is the cutout
used?

As soon as the glower begins to pass
current, the current keeps the tempera-
ture up and the heater is not needed. In
order to prevent deterioration of the
heater and unnecessary loss of power,
the automatic cutout is provided to dis-
connect the heater from the circuit.

1171. How is the cutout arranged?

An electromagnet with a movable arma-
ture is mounted, as shown at C, Figs.
391 and 392, and the armature is held
by gravity in the closed position when
not attracted by the magnet. The wind-
ing of the magnet is connected in series
with the glower and therefore the magnet

Fig. 393. Complete Nernst Lamp

that of a \Q-candlepower carbon-filament
lamp?

The 66-watt lamp is equivalent in il-
luminating power to three 16-candle-
power filament lamps, the 88-watt lamp
to four, the 110- watt lamp to five and
one-half, and the 132- watt lamp to seven.

1174. Explain the parts of the Nernst
lamp shown in Fig. 391.

In this drawing the socket shown at
A takes the fitting on the end of the
ballast tube B; the automatic cutout is
located at C, the glower socket at D and
the heater terminal contact at E. The
screw plug F fits in the standard Edison
lamp socket. The structure shown here
in section is the upper part of the com-
plete lamp shown in Fig. 393.

A smoke-abatement exhibition will be
held in London. England, next spring.
Arrangements are now being made by
the Coal Smoke Abatement Society to
have the exhibition held at the Royal
Agricultural hall. It will cover a period
of two weeks.

LETTERS

Wear of Bearings Due to
Unbalanced Airgaps

It sometimes happens that dynamo
bearings wear very rapidly on the bot-
tom of the sleeve, due to unbalanced
airgaps, which cause a stronger mag-
netic pull from the bottom poles of the
field magnet than from the upper ones.
The beginning of the rapid wear may
be due to faulty design of the boxes, but
it is much more probable that the field-
magnet ring of the generator was set
too high when the machine was erected,
causing an excessive downward magnetic
pull on the bearings from the start.

If the bearings have just sufficient
surface to carry the load under normal
conditions, any extra pressure, such as
might be produced by an unsymmetrical
airgap, would cause rapid wear, which
would, if allowed to continue, become
more rapid as the airgap on the side
causing the excess pressure became
smaller and smaller. The magnetic pull
between the pole- faces and the armature
core is considerable* and it should be
equalized around the armature.

In alternators of large size, there be-
ing no commutation to contend with, it
is customary to adjust the airgaps so
that the pole-faces of the revolving field
magnet will come slightly nearer the
upper than the lower face of the arma-
ture Core, thereby relieving the bearing
of a part of the weight of the revolving
member by the excess magnetic pull at
the top airgaps. I once had an experi-
ence with unbalanced airgaps in a 32-
pole alternator running at 180 revolu-
tions per minute. Two adjacent field-
magnet coils were damaged and in order
to keep running until permanent repairs
could be made, a jutaper was put across
these two coils, thereby cutting them out
of the field circuit. We had no par-
ticular trouble in carrying the load, but
vibration throughout the machine was
noticed and by the time the new coils
arrived (an inter\al of three weeks! the
aimature structure had been rocked out
of alinement, making a readjustment of
the airgaps necessary.

J. B. Clapper.

Lakewood. O.

Arrangements have been completed by
the Imperial Russian Technical Society
for an international engineering exhibi-
tion in April, 1912, at Baku. Russia. The
exhibits will comprise internal-combus-
tion engines, air compressors, electrical
apparatus, etc. The exhibition will run
for a period of six weeks. The exhibits
will be grouped in Baku, and attractively
arranged by the workmen of the tech-
nical society.

•The masnetic pull of a pole-face 10 Inches
square, deliverins .i.iOO.OOO lines of flus, is
apprecial>l.v over 3000 pounds. — Editor.

December 19. 1911

POWER

923

■F^*^

e- i-^m

A Small Producer Gas Power
Plant in a Woodwork-
ing Shop*

By Albert W. Honeywill

The Lampson Lumber Co., of New
Haven, Conn., some time ago installed
in its woodworking shop a small anthra-
cite gas producer and gas engine. The
company manufactures inside "trim" and
all the machinery for this purpose is
driven by the gas engine.

The machinery consists of a molding
machine, a 26-inch planer, a sander ma-
chine, a self- feed grip saw, a variety
saw, a band-saw, a joiner, a cutoff saw,
a boring machine, a lathe, an emery
wheel, a knife-grinding machine and a
fan to remove the sawdust and chips.

In the basement are located the en-
gine room, the producer room and the
pump and baling room. The engine room
contains, besides the engine, an air com-
pressor and compressed-air tanks, com-
pressed air being used to start the en-
gine. The producer room adjoins the
engine room on the north and contains,
in addition to the producer equipment, a
boiler used to provide steam for heat-
ing the building in cold weather.

The engine is rated at 45 hp. at 160
r.p.m. and is of the hit-and-miss type,
operating on the four-stroke cycle. The
governor controls the gas valve only.
The main inlet valve takes in a charge
of air each time; consequently, when no
charge of gas is admitted and no ex-
plosive mixture is formed, the air acts
as a scavenging agent and removes most
of the burned gases from the cylinder.
The ignition system is of the jump-spark
type.

The gas generator is of the ordinary
suctifn type, with a "pan" vaporizer in
the top of it. The grates are stationary
and are located about a foot from the
bottom of the ashpit, which is sealed.
The wet scrubber is of the ordinary coke-
filled tower type. Water from a tank
near the roof is admitted at the top of
the scrubber and is sprayed on the coke
hy means of perforated pipes. The gas
passes from the top of the scrubber to
a cylindrical steel tank of a volume
about one-third that of the scrubber;
this tank acts as a holder for the gas and
also allows any moisture which has been
carried over with the gas to settle In the

•Abntrnrt of n pnpT fad at th<" Npw IIbtoii
tropiInK of the AiDPrlrnn HorlPty of Mprtmn

bottom. The piping from the gas holder
to the engine is short and direct.

The machinery is in operation nine
hours a day, between 7 a.m. and 5 p.m.,
but the engine is kept running during
the noon hour. The load, as is natural
in a woodworking shop, is variable. The
molding machine adds 20 hp. to the load
and several of the other machines, such
as the sander machine, the planer, the
self- feed grip and the variety saws, are
comparatively heavy, so that their use
or idleness varies the load considerably.

The average coal consumption is seven
tons of pea anthracite per month, or ap-
proximately 467 pounds per day. As-
suming an average load factor for the
shop of 40 per cent., this is equivalent
to 2' 1- pounds of coal per horsepower-
hour. The cost of coal delivered is $4.50
per ton, which would make the average
cost per brake horsepower-hour 0.56 of
a cent. No account is taken of the water
as the only cost is that for pumping.

An analysis of the coal gives:

PcTC.ont.

Fixi'd carbon 74 . 95

Vol. oomliustible 6.95

MoUlure ,3.35

Ash 14. T."!

100.00

An analysis of the gas gives:

Percent.

CO 20.9

H 6.7

CO, 2 2

(), .3 4

N 06 S

The average heat value of the gas
per cubic foot is 89 B.t.u.

An analysis of the residue taken from
the ashpit gives:

PrrOnl.
rixMl rarlKin 71 46

A«l] -'s :.i

The producer is charged twice a day,
at the time of firing up in the morning
and again at night. More coal is used,
however, in the morning than in the
afternoon, the charging at the latter time
often being omitted. The fire is poked
regularly at 10 a.m. 1 p.m., .3 p.m. and
again at night. The ashes are removed
in the morning and at night. The at-
tendant arrives at 6 o'clock and starts
the engine at fl:45.

The producer is rather inconveniently
located. In order to get headroom for
charging it was necessary to place the
producer in a pit about five feet deep. A
small coal-storage bin of about two tons
capacity is located at the side of the
producer on the main-floor level. With
this arrangement it is necessary to shovel
the coal into small barrels and lift them
to the top of the producer, and to clean
out the ash it is necessary to climb down
into the pit.

The time required to start from a cold
condition is about two hours. The fire
was pulled out on Nov. 5, after a con-
tinuous run of about eight months.
Inspection of the interior showed the
firebrick to be in good condition. Two of
the grate bars were renewed at that time
and a few have been renewed at previous
cleanings. No other renewals or other
repairs have been made since the in-
stallation of the producer, nearly a year
and a half ago.

An Italian at $15 a week has charge of
the engine and producer; his duties also
include keeping the producer and engine
rooms clean and baling the chips. The
entire cost of power, including coal, oil
and wages of attendant, are covered by
the byproducts of the shop, which in-
clude baled chips, sawdust and partly
burned coal from the producer. The
ashes from the producer are screened
and the half-burned coal obtained in this
manner is used under the heating boiler
and to heat a separate office in the lumber
yard; any not used in this way is sold
at S2 a ton.

The first cost of the plant, including
producer, engine, blower and blower
motor, was about S35O0. The operating
expenses per day are as stated in Table 1.

TAIU.E 1

for
Da.v

Coal. 487 pound.i SI nii

T.abor. one man at %\h per week 2 .*»0

U<-pairs an<l 'li-priTlallon. 10 per cent, per

annum on llr^^t rost 1 16

IntriTsl, .■> jwr ccnl. per annum on flrat

COM O.ftS

Oil and wa.ale, etc 0.14

Taxo. I per rent, per knnura 0.12

»^ M
As previously mentioned, the residue
from the producer is screened and the
recovered carbon utilized for heating.
For this reason it seems fair to charge
only a portion of the coal to the pro-
ducer because if only a small quantity
of carbon remained in the ash it would
be nccessai^ to buy other coal for heat-
ing purposes.

In the course of the ensuing discus-
sion, Mr. Honeywill explained (hat the

924

POWER

December 19, 19U

fact that the sale of chips, sawdust ami
partly burned coal paid the cost of plant
operation was mentioned merely as a
matter of interest; it has no bearing, of
course, upon the cost of operating the
plant. He also stated that his estimate
of the average load (40 per cent, of the
full load) was based on four or five
inspections of the plant at different times
and on estimates by the foreman of the
number of hours each machine runs per
day and the power each requires.

The Operation of Gas Power

Plants

By J. C. Parmely

Perhaps the greatest obstacle prevent-
ing the more general adoption of gas
power for commercial use in the past has
been that this power was not considered
reliable. This was undoubtedly true to a
certain e.xtent, and the reason was that
competent operators were difficult to find
and one of the strongest points made
by over-zealous salesmen was that high-
priced trained operators were not nec-
essary to the successful operation of the
plant. This the purchaser usually found
was untrue, much to his sorrow. Now,
however, this trouble is not so common
and, too, successful operators are more
easily obtained.

About the most necessary element in
the makeup of a competent gas-engine
operator is an ample fund of common
sense. Besides this, the engineer should
have a knowledge of the fundamental
principles underlying the operation of
the gas engine; should be thoroughly
acquainted with the particular engine he
operates; should know all about the elec-
trical equipment of the station, including
the storage batteries sometimes used in
connection with the ignition circuits;
should be a first-class mechanic and able
to make any necessary repairs upon the
machines intrusted to his care; should
know the chemistry of the generation of
producer gas — if he handles a producer
plant — and several other things too nu-
merous to mention. Is it any wonder
that really successful gas-engine op-
erators are difficult to find, or that the
service was not always of the best dur-
ing the early days of the gas engine?

One of the most useful helps in the
operation of any machine is a certain
routine of duties that is gone through
with every time the machine is started
or stopped. Every successful gas-engine
operator w-ill tell you this, for, by fol-
lowing his particular methods, he never,
never, neglects to turn on his jacket water
or pump up the pressure in the air re-
ceiver after starting. One routine estab-
lished in a plant by the writer was as
follows: One man would close the switch
in the igniter circuit, turn on the oil in
the main-bearing cups, go to the switch-
board and raise the voltage on the gen-

erator as the machine came up to speed,
plug in the synchroscope and put the
generator on the busbars in parallel with
the machine in operation. The second
man would climb to the gallery of the
engine, set the mixing valve for the
proper starting mixture, open the valves
in the gas line, and open the air-starting
valve. As soon as an explosion occurred,
which was usually during the first few
revolutions, he would close the air-start-
ing valve and go to the back side of the
cylinders and open the valves in the
jacket-water line while the engine was
coming up to speed. He would then re-
turn to the front side of the engine, ad-
just the mixture valve for the running
mixture and be prepared to reduce the
speed of the engine with the governor,
if necessary in order to synchronize the
generators.

This process may seem long, but it
was usually accomplished well within two
minutes, when necessary to hurry, and in
one instance an engine was started and
brought up to speed with the voltage
raised on the generator in one minute
and the unit was operating in parallel
with its mate twenty-five seconds later.
This plant was equipped with Westing-
house three-cylinder vertical engines of
335 hp. rated capacity each. The fuel
was natural gas.

The worst trouble experienced with
this installation was with a piston that
persisted in running hot. The first indi-
cation would be a light knock, when the
engine was pulling about half load, which
would increase very rapidly in an in-
credibly short time and the engine would
stop within a very few minutes, if the
load were not reduced. This difficulty
was soon Ircated, however, and found to
be due to a crack in the left piston ex-
tending one-fourth the distance around
the piston, and another about 8 in. long
in the cylinder wall parallel to the axis
of the cylinder. This was probably due
to a short nap sometime when the
water was low, and allowed enough leak-
age past tJie piston to heat it until it
would expand and grip the walls of the
cylinder. Upon removing the piston, the
rings were found to be stuck in their
grooves as solidly as though they were
a part of the piston, and cold-chisels
and hammers were needed to remove
them.

The make-and-break igniter plugs were
removed each week and cleaned and
tested for grounds. The mixing valves
were also cleaned each week for the air
supply was taken from a rather dusty
atmosphere and parallel operation of the
units demanded that the mixing valves
move freely in their bushings.

The operation of a producer-gas power
plant is much more complicated than
that of a plant burning natural gas. One
plant in which the writer gained some
good experience was equipped with two
Miinzel engines of 280 and 100 horse-

power each, which were two-cylinder
(twin) and single-cylinder engines, re-
spectively. Gas was furnished by two
producers of the same make, rated by the
makers at 150 horsepower each. These
producers delivered their gas to the same
set of wet and dry scrubbers. Buckwheat
coal was burned for fuel. The load re-
quired the operation of only one engine
at a time.

In the case of the producer plant, the
successful operation of the engines, aside
from purely mechanical troubles, depends
very much on the degree of common
sense displayed in the operation of the
producers. A prominent builder of gas-
producer plants is quoted as saying that
the best producer operator he ever em-
ployed was the laziest man he ever saw.
This is without doubt very true, for pro-
ducers of the suction type must be kept
closed as much as possible and the qual-
ity of the gas made will not be uniform
if the fire is continually being disturbed
by poking. In this plant the fires were
cleaned twice in 24 hours. The grates
w^ere shaken at this time and the fires
poked down. The fires were poked again
about midway between cleaning periods
and coal was fed from four to six times
per day, according to the load. It was
found that the best results with regard
to operation were obtained with the pro-
ducers under light load and for this rea-
son both producers were used continually
during the 24 hours. The producers were
under fire for as much as a year at a
time.

For the first few months in this plant
considerable trouble was experienced
with preignition. This would occur at
various times when the load conditions
were entirely different. In some instances
it was severe enough to slow the engine
down considerably. It may usually be
stopped, if noticed in time, by cutting
down the supply of steam to the air
entering the ashpits and perhaps opening
the ashpit doors slightly, which allows
the air to enter the firebed without hav-
ing passed through the preheater. This
will make a gas of poorer calorific value.
It may also be helped by using a smaller
ratio of air to gas in the cylinder, which
gives a richer mixture and one that does
not bum as rapidly as the most efficient
mixture. After learning to successfully
carry the engines through these bucking
periods a change in cylinder oil prac-
tically put an end to trouble with pre-
ignition.

The question of preignition is one that
has not been solved satisfactorily, as yet.
Many think it is entirely due to the hydro-
gen content of the gas, but this cannot
be true for gases containing as high as
25 per cent, of hydrogen have been used
successfully; a gas containing the same
amount of hydrogen will behave very
differently at different times, and. fur-
ther, pure hydrogen will not ignite at the
temperature due to compression.

December 19. 1911

POWER

925

Hot Water Heating for
High Buildings^^

By Ira N. Evans!

If often occurs that 300 or 400
horsepower in boilers are required for
the heating of a large building, whether
the electric power is furnished or not.
Has it ever occurred to the engineer or
owner that this same heating system, if
made air-tight, would have the power to
act as a condenser to produce vacuum
and would thus greatly increase the
power economy over noncondensing con-
ditions?

Unfortunately it is almost mechanical-
ly impossible to make an ordinary steam-
heating system air-tight, but the results
claimed above can be obtained with a
properly arranged system of hot-water
heating under forced circulation and a
large saving effected in the use of fuel
on power and heating combined.

The commercial cast-iron radiator is
unsafe under a water pressure greater
than 100 pounds, so that hot-water heat-
ing has been limited to buildings of less
than 14 stories, where the static pres-
sure will be within the stated limit.

As these buildings have become greater
in hight and area, the power load for
lighting and elevator ser\'ice has in-
creased proportionately. Due to the me-
chanical difficulties of making the piping
air-tight, it is impossible to take ad-
vantage of the increased surface of the
steam-heating system to produce vac-
uum on the engines. They are operated
at atmosphere and the exhaust steam is
utilized in the heating system at the same
pressure.

The necessities of the low-pressure
steam-heating system have eliminated all
consideration of a condensing plant out-
side of the expense of using city water
for injection. The same considerations
have prevented the use of the turbine, in-
asmuch as this type of machine is very
costly to operate under back pressure or
no vacuum, the steam consumption being
about 45 pounds per kilowatl-hour on
a .V)0-kilowatt unit exhausting at at-
mospheric pressure at full load.

The engines for high buildings are
seldom compounded, and the whole sub-
ject is no further considered than the
fact that exhaust steam is required for
heating, seven months, and the amount is

•'■f1>yrlBht«l. Kill. Ly Irn N Rvriix.
+roni<t)ltlnir pnelnpcr. hpntlnK and power,
ine BronilwR}-. .N>w York I'lty.

estimated under the conditions of no
back pressure in zero weather.

This fixes the heating-surface tem-
perature at 212 degrees at all times and
observation in the afternoon in most of-
fice buildings will show open windows
with the radiators turned on, thus wast-
ing the hea* to the outside. If the sys-
tem could be operated at lower tempera-
tures, this waste could in a great meas-
ure be eliminated.

The hot-water system herein described
may be applied to the highest buildings,
the engines or turbines operated con-
densing and the temperature of the cir-
culated medium varied so that without
shutting off the radiation the rooms will
not be overheated.

The most economical feature in the
operation of such a system is the fact
that the temperature of the water can
be varied from 200 to 100 degrees with
a corresponding saving in heat units
whether exhaust or live steam is used
for heating. No more heating surface is
required than for vacuum systems as
the medium in zero weather is at the
same temperature in both cases.

Figs. 1 and 2 show diagrammatically
how a hot-water system may be ar-
ranged for a building of any number of
stories, the power plant operated con-
densing all of the time and the heating
system utilized as a condenser to the ex-
tent of its capacity at any given out-
side-weather condition. To reduce the
static pressure on the radiators the sys-
tem is divided into several independent
units, utilizing the steam from a common
source.

For buildings 12 stories and under, one
system is all that is necessary regardless
of the area covered, and the heaters and
pumps would be placed in the basement,
but the condensing feature hereinafter
described could be applied. For build-
ings under 20 stories and more than 12,
two systems would be required, and for
buildings 20 or more stories in hight
every 10 stories would require a separate
system or unit, such as is shown in Fig.

2. The heaters and pumps can be placed
in a room of little value. Places of this
character, such as a poorly lighted room,
can be found in almost all buildings, and
.Tt that the required space would not be
more than 15x20 feet on every tenth
floor. The most advantageous place
would be next to the shaft carrj-ing the
boiler flue and exhaust piping. The sep-
arate heaters and pumps can all be
placed in the basement by installing long
vertical supply and return water pipes.
The heaters would then have to be built
to withstand the static pressure, but the
pressure on the radiation would be with-
in safe working limits.

The arrangement shown contemplates
one supply and one return pipe to the
various stories. Each floor is divided in-
to one or more sections as shown and
served by a single I'j- or 1 '4-inch pipe,
depending on the amount of surface and
floor area, and the radiators are con-
nected in shunt or out and back into
the same pipe.

Fig. 3 shows how this pipe may be run
behind a removable base, or it may
be run between the sleepers carr>ing the
finished floor. Under these conditions a
I'j-inch pipe will take care of 1000
square feet of radiation and a I'i-inch
pipe will supply 600 to 800 square feet
of surface with the same drop in head.
Fig. 1 shows each floor divided into two
sections, which would allow a maximum
of 2000 square feet of surface to the
floor. When the lower floors of a build-
ing are of greater area than the upper
stories, an overhead system with single
risers may be used for the lower por-
tion, allowing the same capacity for each
riser. For the tower the scheme suggested
in the diagram will prove the most eco-
nomical to install. The great advantage
of this system is the elimination of all
risers with the expansion pieces extend-
ing into the rooms and the ugly holes
at the floor and ceiling in each case. If
the pipe shown in Fig. 3 was run ex-
posed on the base, there would be no
more pipe showing than in the case of
runouts to risers in most cases, and
the breaks would provide amply for ex-
pansion. The main pipes for this layout
would not be over 5 inches in diameter
in any case with branches of 3 or 4
inches, which is no larger than the sin-
gle steam risers in the ordinary build-
ing for each line of radiators.

Objection may be made to concealing
the piping, and in the case of sicam,
due to the sudden expansion strains

926

POWER

December 19, 1911

which do not occur on a hot-water sys-
tem, the objection would be sustained.
The writer designed a system for an
office building in Boston where all water
piping was concealed under the floors
and behind the plaster and after 12 years
the system has given no trouble whatso-
ever. The piping, however, as thor-
oughly tested for expansion t.nd pres-
sure.

As shown in Figs. 1 and 2, the heaters
and pumps are connected in series, and
horizontal main supply and return pipes
only appears on every tenth floor. This
piping might easily be run in the furred
ceiling of the corridors. Under these con-
ditions the covering for the piping would
not be needed and the omission of auto-
matic heat control would reduce the cost
of installation of the water system to
that of a low-pressure steam system, the
extra cost of heaters and pumps neces-
sary for the hot-water system balancing
the cost of covering and control ap-
paratus.

The live-steam heaters L, which are
very small, connect with independent
steam and return lines from the boilers;
the condensation is thus returned by
gravity to the boilers without pumpitig
or releasing the pressure. Full boiler
pressure may be used, and by throttling
the individual returns any temperature
may be maintained by allowing the con-
densation to back up and to cover that
portion of the tube surface not required in
the live-steam heater. The returns need
not be over IJ4- or I'/^-inch pipe. The
pump capacity need not be over 15 horse-
power.

When the main engines are operated
24 hours, motor pumps should be used
throughout, but if the engines are to be
inoperative at any time one steam-turbine
pump should be used and one motor-
driven pump. The steam-turbine pump
could be connected to the steam line to
the live-steam heater and exhaust into
the exhaust heater. This would make the
heating system independent of the en-
gines at all times.

The exhaust line would be connected
to each heater, as shown, and the en-
gines operated at atmosphere when de-
sired by opening the relief valve shown
in Fig. 2.

The only precaution necessary in this
system is to be sure the exhaust pipe is
air-tight; this will present no difficulty
if the proper material is selected before
erection.

Each exhaust heater is provided with
a single connection with a long drop and
loop of pipe not over 2 inches in diam-
eter. The intermittent siphon action of
these lines will produce a vacuum and
remove the air. The lines lead to a
header which is connected to the con-
denser. A motor-driven pump should re-
move this condensation to the feed-water
heater, where sufficient auxiliary exhaust
steam should be provided to raise its

temperature to 212 degrees before re-
turning it to the boilers.

On a job of this kind as much of the
machinery should be operated electrically
as possible so as to load the turbine; at
the same time the units should be se-
lected with regard to the heating load.

The expansion tanks should be op-
erated by hand with air pressure, as
heretofore described, and there should
be absolutely no connection between the
water systems for the different levels.

September 12 issue, shows the steam
consumption of a' turbine under constant
load that will just balance the heating
requirements from 0 to 60 degrees by
varying the amount of vacuum.

Curve H shows the heating require-
ments of a hot-water system of about
70,000 square feet of surface. Curve T,
shov.-ing the steam consumption of a 500-
kilowatt turbine unit under a constant
load of 400 kilowatts and operating at
different vacuums, shows an exact bal-

Circulating 'p'um;a"'''''^^Hoi'w'eii 'Pumps

Fic. 1. Diagram of Hot-water System Proposed for High Buildings

'/////////////,

Objection may be made to operating ma-
chinery on different floors away from
the engine room, but with proper water
gages for each system corrected for dif-
ference in level the exact action can be
determined in the engine room.

These pumps require little or no at-
tention except r.t regular interx'als and
recording thermometers can be arranged
to read the water femperature of each
system in the engine room.

Fig. 4, which was taken from the

ance of the heating-steam requirement:-
in temperature and amount.

The vertical distance between the
curves shows the portion of the work on
the condenser which is nearly constant
throughout the heating season and about
2000 pounds per hour, or 20 per cent.,
of the requirements of a 500-kilowatt
load at 20 pounds per kilowatt-hour un-
der 28 inches vacuum.

It is due to this proved condition that
a turbine-unit, cooling tower and con-

December 19, ISfl

POWER

denser properly balanced to utilize the
exhaust steam under partial vacuum on
a hot-water heating system will prove
38 per cent, more economical for the
combined heating and power than a vac-
uum system and engine plant operating
at atmosphere with no vacuum.

Engineers as a rule will state that a
condenser will not pay as their asser-
tion is based on curves H' and T", which
would be nearly constant with a vacuum-
heating system under all weather condi-
tions.

In Fig. 1, a cooling tower with sur-
face condenser, is shown recirculating
the water for condensing purposes. A
fan and motor would have to be provided
or, where possible, the air for the tower
could be combined with the engine-room
ventilation, the hotter air being very ef-
ficient for cooling-tower purposes. A flue
provided with conical wire screens should
lead from the cooling tower to the ex-
treme top of the building to carry off
the vapor and prevent condensed water
from falling on the roof and street. The

inder oil is eliminated and distilled water
is obtained for the boilers.

Two motor-driven circulating pumps
would be provided to circulate the in-
jection water and the vacuum on the
system could be varied by throttling the
circulation or varying the speed of the
pumps.

It may be readily seen that the cost
of operating this condensing apparatus
would be negligible in many cases in
connection with the heating system ex-
cept for the interest on the additional
investment.

When less power is generated than
the balanced load, the vacuum will have
to be reduced, to increase the quantity
of steam to maintain a proper water
temperature on the heating system.

It will not pay to carry normal vac-
uum for that outside temperature and
operate the live-steam heater to furnish
the additional heat, although the ap-
paratus is arranged 'so that this could
be done.

Unless Great caution is used, if both

noon for three or four hours the heating
requirements are minimum and a slightly
higher vacuum can be carried than the
outside-heating requirements demand
without causing complaint. If the out-
side temperature were 35 degrees, the
average in the vicinity of New York, 24
inches instead of 20 inches could be
carried and the full condensing power
of the heating system utilized with the
condenser assisting. The low-steam con-
sumption of the turbine for overloads
would make an economical arrangement
for the peak load. It might be policy
where the heating was in excess of the
power load to install only one-half the
condensing capacity, operating the ma-
chine in summer on such \acuum as

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cooling tower might be operated with
natural draft in winter and the fan and
motor shut down with corresponding re-
duction in operating expenses.

Where possible, a driven well could
be provided with an air lift to furnish
the water supply for the injection which
is evaporated by the cooling tower. After
passing through the condenser the water
could be used for flushing the closets,
providing an equal amount of cooler
wafer to replace that removed, and ma-
terially assisting the action of the con-
denser. This arrangement would reduce
the city-water bill for power and flush-
ing purposes ))i'hcre well water for boiler
use would be unsuited. due to impuriiic"!.

B) installing a turbine the use of cyl-

heaters are operated in conjunction, with
the exhaust heater under vacuum, the
latter may be cooling the water heated
by the live-steam heater, thus entailing
a heavy waste.

In the ordinary office building the load
for lighting and elevators during the
winter days is a little more than 50 per
cent, of the peak. At such times the
turbine would have to operate on a lower
vacuum than the maximum that will fur-
nish the proper water temperature, but
the underload on the turbine with in-
creased steam consumption per kilowatt-
hour would be no added expense as it
would be demanded in any case by the
heating requirements.

When the peak comes on In the aficr-

could be obtained. The total steam from
the power load might be such that one-
hall the condensing capacity at full load
and vacuum would produce a fairly high
vacuum at one-half load.

If a condensing capacity for 6000
pounds of steam per hour were installed
for a .500-kilowatt unit in conjunction
with the heating instead of 10,000 pounds,
or 500 kilowatts at 20 pounds, 2H inches
of vacuum would be produced on a 250-
kilowatt load at 2.1 pounds per kilowatt-
hour. In winter this would be ample
to maintain with the heating any vac-
uum desired at full load.

In case the building was not large
enough to require a toad that would war-
rant a condenser and a coolinR tower.

928

POWER

December 19, 1911

a fresh-air supply could be* arranged on
the roof with a fan and indirect staclv
connected to one of the hot-water sys-
tems. This would form an efficient air
condenser and the ventilation of the
building could be accomplished at the
same time. This would be especially
desirable where the power load was
somewhat less than the heating require-
ments and not large enough to warrant
condensing apparatus. The fan system
is indicated in Fig. 1.

The time the building ventilation would
be most desired would be in moderate,
damp weather when the heating system
would be at low condensing capacity. In
very e.xtreme weather the fan ventilation

when the steam consumption is figured
at 212 degrees and all surface is in op-
eration.

The extra cost would involve circulat-
ing pumps, a cooling tower and a con-
denser, with the piping connections.

If the temperature of the air averaged
about 35 degrees and the temperature of
the water 155 degrees, the average vac-
uum would be 20 inches. The steam
consumption of the reciprocating engine
of the best type at atmosphere would be
25 pounds of steam per indicated horse-,
power. Allowing 20 per cent, for fric-
tion of the engine and miscellaneous
losses, a kilowatt at the switchboard
would require 40 pounds of steam per

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Water Temperature
* I 9 I 11.5 I 14 I 17 119.5 1 22
Vacuum, Inches

55 60 65 70

Fig. 4. Curves Showing Relation between Steam Consumption of
Turbine and Requirements of Hot-water Heating System

would not be as necessary and the heat-
ing system would have greater efficiency
as a condenser.

From the article published in the
September 12 issue the saving of the
hot-water system during night opera-
tion, when live steam is used, is shown
to be 35 per cent, over the low-pressure
steam system at 212 degrees, due to the
ability to change the temperature of the
circulated water to suit outside-weather
conditions. The gravity return of the
condensation to the boilers under high
pressure and temperature over the reduc-
ing-valve pump and receiver method en-
'hances the saving 10 or 15 per cent,
and would balance the percentage of
radiation turned off in moderate weather

hour. The turbine with 500 kilowatts
load at the switchboard and 20 inches
of vacuum requires 30 pounds per kilo-
w'att-hour. This shows a saving of 10
pounds of steam per kilowatt-hour.

Allowing 1500 hours per year (5 hours
per day for 300 days') for the peak load
of 500 kilowatts, 8 pounds of evaporation
per pound of coal and S4 per ton of
2000 pounds for fuel, the saving would
be

5cx> X 1500 X 10 ^, ^ i- o /: A

g^,^ X $4 = S1876 per year

The total cost of the cooling tower,
pumps, condenser for 500 kilowatts at
20 pounds under full vacuum, or 10,000
pounds of steam per hour, is $8000
erected. The saving with this equip-

ment installed would amount to 23.45 per
cent, of its cost.

The saving on a 300-kilowatt plant
would be somewhat less in proportion,
but would still leave ample margin to
warrant the adoption of this type of
plant.

In plants under 250 kilowatts it would
be better practice to use reciprocating
engines compounded and operate on such
vacuum as the heating system will pro-
duce with outside-weather conditions,
omitting the cooling tower and con-
denser.

From observation, it is found that gen-
erally there will be about 100 square
feet of heating surface to the kilowatt
of power in buildings of this class and
that the steam for the day load can
easily be condensed in the heating sys-
tem.

It is impossible to give more than an
outline of the scheme in the space al-
lotted and the problem can be developed
only when a concrete case is presented.
But if the system was adopted along the
lines presented, with fairly intelligent
operation, an isolated plant should pro-
duce current at the switchboard for the
owner at a very low cost.

The saving involves the double effect
of reducing the steam for power and the
steam for heating at the same time. The
condenser takes the slight hourly excess
of the steam for power over heating and
prevents this excess heat from accumu-
lating and destroying the condensing ef-
fect of the heating system.

It should be remembered that there are
ample precedent and engineering data to
assure results as stated. The system
would be particularly advantageous for
hotel work, where night-and-day opera-
tion is obligatory. The flexibility of
water heating would here show up to ad-
vantage over a medium which must be
maintained at 212 degrees.

The insertion of a check valve in the
gas-supply line between a suction pro-
ducer and a gas engine operated from
it has been found effective at a number
of gas-power plants in reducing the
troubles arising from backfires in the
intake line caused by poor gas at times
of cleaning the producer or changing the
load, says Mechanical World. Without
the check valve the backfire in the sup-
ply main usually partially consumes the
gas in it back to the purifier or scrubber,
and so weakens it that, particularly in
case of a long gas-supply line, a con-
siderable period intervenes before gas of
a good quality again reaches the en-
gine; this causes a serious drop of speed
in the latter, or sometimes even a stop-
page. By placing a swing check valve
in the line close to the engine throttle
and opening toward the latter, such a
backfire cannot reach the gas beyond it,
and has no appreciable effect on the en-
gine's operation.

December 19, 1911

POWER

Issued Weekly by the

Hill Publishing Company

JoHM A. Hill, Pres. and Trcas. Bob't McKban,^^'^.

505 Pearl Street. New York.

122 Sonth Ulchlesn Bonlevunl. Chlcaga

6 Bouveric SlTTCt, l>indoii. E. 0.
Un't«r den Lloden 71— IkTlln, N. W. 7,

Correspondence suitable for the col-
umns of PowEH solicited and paid for.
.Name and address of correspondents
must be given — not necessarily for pub-
lication.

Subscription price 82 per year, in
advance, to any post office in the United
.States or the po.'isessions of the I'nited
.States and Mt xico. S.i to Canada. S3
to any other foreign country.

Pay no money to solicitors or agents
unless they can show letters ot authoriza-
tion from this office.

Subscribers in Great Britain. Europe
and the British Colonies in the Eastern
Hemisphere may send their subscriptions
to the London Office. Price 21 Shil-
lings.

Entered as second class matter. De-
cember 20, 1910, at the post office at
New York, New York, under the Act
of March 3, 187fl.

Cable address, "Powpub," N. Y.
Business Telegraph Code.

CIliCULATWX STATEHEST
Of th{a insue 30,000 copies are printeil.
None sent free regularly, no returns from

netcs companies, no back numbers. Figures

are lire, net circulation.

Contents ^

Isolated Power for Making Shoes

Cost of I'ower In New England Mills. . . .

Davles" Experience, a Tragedy

First Western Built Automatic Engine..

Is Peat an Important KncI In he V. S. ?

Smoke Abalcment In Orei.t Britain

Failure of a Surface Condenser

Catecblsm of Electricity

Wear of Benrlngs Due to Unbalanced
Airgaps ,.

A Small I'ro<lucer Cns Power Plant In a
Woodworking h.hop

The Operation of fias Power Plants

Hot Water Heating for High Buildings..

Kdltorlals I>29

Practb'al lietlers :

Briiken Valve Cros-iheiid . . . . Unslwd
the Cylinder .... Inloador <; n v n
Trouble .... Test of Pumping Entlnp
....Hmalt .Machine Fonndalloni .. .
A Pumping Problem. .. .I'nnsnal Ar-
rangement of CondeniKT. ... Isolated
Plant Owners I(pHpiin'<lble !i:il

Discussion l.eiiers :

Tail IlfHl Stufllng Iloi....Alr Cnm-
pressor Rimning T'nder .... l/i-aky
Corliss Valves. ...Christie Air .steam
EnKlne. . . .Hand for Hot li'MihiL's
.... Show versus Edlcbnrj ...

Water In Ilol llr.t Boiler lining

on Htorage Tank Orafl A

Twenty Four Hour I<og, . . .Cenlrlf-
ugal Pump Cniincliy and 8pe<Hl.,..
Kniclency of Kei Iprocaling Knglnen
.... License I^ws Ii34

Annual Meeting of Merbanlcal Rnglncrs

Good Engineering Judgment

The value of an engineer is measured
by liis ability and his trustworthiness.
These qualities are dependent upon two
things: knowledge of facts and good
judgment. Either of these is of little
value in the makeup of the good engi-
neer unless accompanied by the other.
A knowledge of facts is essential, but it
is also necessary to know how to apply
those facts. This is the reason why the
"textbook engineer" is so universally be-
rated; he has not acquired the requisite
judgment with which to apply his knowl-
edge.

The way to obtain a store of knowl-
edge is open and clear. Facts seemingly
difficult to master become a personal
possession after an application of deter-
mined perseverance and courage. Patience
is required, indeed, and also those habits
of discipline which are so necessary to
the efficient engineer. The sources of
engineering knowledge are conversation
with experienced engineers, observation
of things and affairs, the study of good
engineering books and the reading of
the leading engineering journals.

The means by which to acquire good
judgment are not so apparent. This is
largely inherent in the man, but, of
course, may be cultivated to some ex-
tent. Good judgment is the result of ex-
perience, and experience may be ac-
quired by storing away the lessons which
are taught daily in the doing of or-
dinary tasks and by observing the ex-
periences of others. It is a silly person
who will repeatedly make the same mis-
take and repeatedly suffer the same
punishment therefor.

Good judgment Is fostered by a care-
ful reading of current technical literature.
The technical papers contain a wealth of
material which tells of the experiences
of others. These articles should be
studied in a spirit of fair-minded crit-
icism. Has the writer told of an experi-
ence which will be of assistance to you
in a similar need? Well and good. Are

your conclusions the same as his, or are
you able to improve upon them?

In an emergency, dependence must be
placed upon good judgment. It is well to
anticipate an emergency. Many times
every day the safety of life and property
depends upon the quick decision and the
immediate action of the engineer. No-
where is this more apparent than in the
operation of a power plant. In the en-
gine room the operating engineer is fre-
quently called upon to meet an emer-
gency. A quick decision is more likely
to be correct if it is based consciously or
unconsciously upon a carefully thought
out plan. Such a plan cannot well be
formulated unless the emergency has
been anticipated.

Good engineering judgment is not a
haphazard accomplishment. The engi-
neer who possesses it Is respected and
admired, but many do not stop to think
that he has acquired it by constant and
continuous effort.

Water in Ashpits

The practice of putting water In the
ashpit, ostensibly for the purpose of pre-
venting the formation of clinker, has
many adherents among firemen and en-
gineers, while, on the other hand, there
are many who claim that the effect is
merely Imaginary.

It is now generally conceded that the
formation of clinker is due to low fusing
temperature of the ash. If this^empera-
ture is less than that of the fire, the ash
will fuse and flow to the bottom of the
fuel bed, where, coming in contact with
the colder air from the ashpit, it solid-
ifies either in the form of large clinker
or spreads over the grate bars, thus ob-
structing the air passages.

Steam jets under the grates have been
found to reduce the clinker to some ex-
tent, presumably by lowering the tem-
perature of the fire to a point at which
the ash will not fuse so easily. Whether
the relatively small amount of steam
formed from the water in the ashpit

930

POWER

DecT-nbcr 19. 1911

■would accomplish this purpose is ques-
tionable. If the difference between the
temperature of the fire and that corre-
sponding to the fusing temperature of the
ash were small it is conceivable that the
heat given up in dissociating the steam
might be sufficient to reduce the tem-
perature of the fire through this range;
but where the fire is several hundred de-
grees hotter than the fusing temperature
of the ash it is doubtful if this action

would OCCUT.

Water in the ashpit, however, does
serve two other useful purposes: First,
it absorbs much of the heat which would
otherwise be radiated back from the hot
ashes to the underside of the grate bars
and thus protects the latter; second, by
wetting the ashes, fine dust is prevented
from spreading over the boiler room
whenever the grates are dumped or the
ashes removed.

These latter considerations alone are
enough to warrant the practice being
adopted under certain fire-room condi-
tions, which may or may not be such as
to render effective this means of pre-
venting clinker.

New Yoik State's Water
Powers

The question of conserving the water
powers of New York State was once
more brought to the front when the joint
legislative committee having this sub-
ject under consideration met recently
and listened to testimony from Gifford
Pinchot, ex-President Roosevelt and
others prominently identified with the
movement.

It was estimated that fully two million
horsepower could be made available by
the development of these water powers.
Furthermore, if carried out along proper
lines, such a development would serve
the additional purpose of regulating the
flow of the Hudson, Genesee, Black,
Oswego and other rivers. Most of these
at certain seasons are so swollen as to
flood and do considerable damage to
property along their banks, while at other
times they are almost dry.

As all navigable streams are under
federal control while the others come
under state supervision, there has been
a division of authority; hence a solu-
tion of the problem demands cooperation

of these two branches of the govern-
ment.

It appears that prior to the present
agitation, the government had been in
the habit of making perpetual grants of
water powers to private interests with-
ov.t receiving anything in return or malc-
ing provision for adequate supervision
and regulation. Under these conditions
many grants had been taken up for
speculative purposes which have not been,
developed and the parties concerned now
deny the right of the government to act
further in the matter.

Some of those present at the confer-
ence were in favor of the state taking
the initiative and constructing the nec-
essary' dams, etc., then selling the privi-
leges to power companies. However, ob-
jection has been advanced to this pro-
posal in that, according to the plans sug-
gested, it would involve an enormous
expenditure for wh'ch state bonds would
have to be issued. The amount of power
used might, for a number of years, be
only a small part of that made available;
consequently the rentals, which would
necessarily have to be nominal, would
not be sufficient even to pay the interest
upon the investment.

A much better plan, it would seem,
would be for the state to undertake such
work upon a smaller scale and only
when it was reasonably sure that the de-
mand for power within a few years will
warrant a return sufficient to cover the
interest.

Or, on the other hand, it might be ad-
vantageous to permit the developments
to be carried out, as needed, by private
capital under lease. This would not nec-
essarily involve the surrender of any
state's rights, as public-service corpora-
tions are now beginning to acknowledge
the justice of governmental supervision.
Of course, no private corporation can
be expected to enter into any enterprise
unless it can see a fair profit ahead, and
any arrangements made with the state
must take cognizance of this; but state
supervision can, by fixing equitable rates,
prevent excessive profits at the expense
of the public.

In this connection it may be remarked
that the rights of the public can be pre-
sen-ed against oppressive rates and
monopolistic control by a provision per-
mitting the state at any time to step in
and operate its own utilities.

"Trade" or "Profession"

Steam engineering is considered by
some people a profession, while others
ccoff at the idea and insist on calling it
a trade. It really makes very little differ-
ence how it is classified, but to those
v.'ho like to dwell on the subject the
following quotation may open up a new
line of thought.

In an article which appears in a re-
cent issue of The Youth's Companion,
entitled "The College in the Service of
the Nation," President Hadley, of Yale,
has this to say:

Most yoople think that a profession is a
business like law or medicine or teaching,
which roqtiires a groat deal of learning for
its successful exercise. On the other hand,
the.v apply the name trade to a business for
which a hoy prepares himself in the office or
the shop, and which Vioes not demand hook
knowledge as a basis for its successful
prosecution.

This is not the right way to look at the
matter. The real difference lies not in the
character of the business, or in the kind of
learning that is" needed for its pursuit, but in
the spirit in which it is carried on. Any
business, h.owever scientific, which a man
does primarily for the sake of the money that
he can get out of it is a trade. Any business,
however simple in its character, where a man
thinks first of the work that he is doing and
only secondarily of the pay that he is going
to get for it, deserves the name of a profes-
sion. If a carpenter thinks more of the
solidity of his work than of the profit that
he is going to make from it. he has the right
to call his carpentry a profession. If a min-
ister thinks more of the pay that he is going
to get for his sermons than of the souls that
he is going to convert by them, he has no
right to call his business anything but a
trade.

Doctor Hadley's definitions of "trades"
and "professions" are radical departures
from the generally accepted meaning of
those terms. But if he is right, then,
judging from the pay that most engi-
neers receive and the contentment with
which they receive it, yea, verily, they
are not tradesmen; they are professionals
of a high class!

All steamships have a system of
thorough inspection in the engine rooms,
both during each watch and on changing
watches. The small "thickness" between
the men and the deep blue sea is doubt-
less an incentive for additional care. But
"thickness" works both ways, as was
evidenced by a remarkable explosion in
New York City on October 20, when a
return-tubular boiler 15 feet long and
60 inches in diameter plowed through
150 feet of obstructions under a siae-
walk, including a 3-foot brick partitioo
wall. Carelessness and thickness are
synonymous when it comes to a question
of explosion and breakdowns.

December 19, 1911

POWER

Broken Valve Crosshead

The small head-end steam-valve cross-
head on a lOOO-horsepower cross-com-
pound Green engine had given consider-
able trouble. The engine had been in
operation about one year when the bolt
between the valve stem and crosshead
sheared right off at A, shown in the il-
lustration. The oiler and the assistant
engineer were much surprised to see the
receiver pressure suddenly drop, and
then fluctuate from a vacuum to a very
few pounds pressure.

After the trouble had been located the
cutoff was changed on the crank end to
maintain a steady receiver pressure
slightly above zero. But this did not
help matters, as the high-pressure cyl-
inder was discharging steam into the re-
ceiver to make up the loss and the low-
pressure valve was wide open. The

Where the Crosshead Broke

problem was how to get the valve shut.

The broken bolt was removed and
a wooden block was put under the nut to
hold up the toe from the tappet, the
rocker shaft being at rest. A piece of
heavy copper wire was passed through
tTie hole in the end of the valve stem,
making a loop through which the end
of a crowbar was passed. With this ar-
rangement the valve was closed.

The cutoff was then adjusted to let
the steam through on the crank end and
a new bolt was put in, to hold the valve
stem and crosshead together, while run-
ning; readjusting the cutoff completed
the job.

About a month later the crosshead
parted, as shown in the illustration, leav-
ing the valve open. It was finally closed
and the toe blocked up so as not to en-
gage the tappet until the engine could be
shut down, as the back of the crosshead
struck against the crosshead of the crank-
end valve stem. The broken crosshead
was removed and the engine started and
rar three legged, so to speak, with the
high-pressure cylinder and one end of
the low-pressure cylinder until a new
cros?head was obtained.

There was always excessive wear of
the adjusting wedge on this crosshead
and the bolt and the toes met with fre-
quent accidents by being broken off on
the corners; the tappets were occasional-
ly nicked on the corners. The steam-
chest cover was removed but no sign of
an obstruction to the operation of the
valve was found.

This engine was frequently overloaded,
often carrying 1200 horsepower, and the
receiver pressure would run from zero
at no load to 18 pounds at full load, con-
densing.

If this excessive receiver pressure
could spring the center of the gridiron
valve down enough to make it catch in
the grid seat, the cutoff or closing edges
failed to show it, as they were as sharp
as a knife edge.

The high-pressure cylinder, too, has
had its share of the head-end valve
sticking, but the only damage was the
wearing of the toes and nicking the tap-
pets.

Can any of the readers of Power give
any intelligent suggestions as to the
cause of this trouble? Cylinder oil is
used very freely on this engine and the
valve and seat show a very smooth
glazed surface.

• R. A. CULTRA.

Cambridge, Mass.

BiKslied the Cylinder

I was once called upon to make a
quick repair on a planing-mill engine.
A broken piston rod had knocked out
the cylinder head and with it a portion
of the cylinder. The break in the cyl-
inder was about 14 inches, or one-fifth
of the cycle of the cylinder and about
6 inches deep toward the crank end. The
shape of the cylinder was such that it
was impossible to use lie bolts from
the heads to the crank-end cylinder. The
engine was of I.V) horsepower capacity,
but was only developing W horsepower.

I took the cylinder to a local shop, had
a bushing turned and pressed Into the
broken cylinder. I then bolted the new

cylinder head on to force the broken por-
tion of the cylinder in place and then
drilled through the broken cylinder with
\s-inch holes, H inch deep in the bush-
ing, which was I inch thick. The holes
were for 's-inch cap screws and the
I token piece was bolted on the same as a
soft patch on a boiler. This job proved

Bushed Cylinder

entirely satisfactory. It is shown in the
illustration. A repair of this kind could
not be resorted to if the engine were
properly loaded. The job cost S42.

J. H. Dixon.
Bamberg, S. C.

L'nloader Gave Trouble
About two months ago I had a 12x8-
inch air compressor installed which was
used for a humidifying system and air-
cleaning textile machinery. This machine
is fitted with what is called an unlnader
which automatically opens and shuts the
inlet to the compressor, to suit the re-
quirements of the system.

The device was set to maintain 35
pounds pressure. When first started up
it ran for two or three days with a varia-
tion of 4 pounds, opening when the
pressure was reduced to 31 pounds and
closing at 35 pounds per square inch.
After running three days, the oil cup was
filled with oil to lubricate the air-cylinder
piston and this made things worse as
the variation in pressure became greater,
ranging between 35 and 25 pounds.

On invcsiigatinc the unloadcr I re-
moved the air-cylinder piston and found
that it was not being lubricated. This
was due to the flow of air at 35 pounds
pressure forcing it* way between the air-
cylinder piston and the cylinder wall,
there being no rings on the piston This
leakage of air was caused bv j too snihll
airport in the head of the air-cylindcr
piston, and it was also necessary to give
the regulator-valve spring more tension

932

POWER

December 19, 1911

than should have been necessary, thus
forcing the air between the piston and
the cylinder wall, which carried the lubri-
cation out into the intake pipe to the
compressor.

It was found that the housing around
the diaphragm formed a receptacle for
sediment and any oil which might drip
in when the compressor was shut down
as well as the moisture which came
through the air pipe with the air. This
settled on the diaphragm and added more
weight to it, thus keeping the needle
valve open longer. The small airport in
the head of the piston, which took longer
to exhaust when the needle valve was

BioY/off
Pipe

Q^S:^—^

carrying with it what lubrication leaves
the oil cup. This oils the needle valve,
making an oil seal when the needle valve
is shut, thus allowing the air to exhaust
and the unloader to open; then the com-
pressor raises the pressure to 35 pounds,
and the diaphragm pushes back against
the diaphragm spring, opening the needle
valve and allowing the air to pass be-
hind the air-cylinder piston. This forces
the regulator valve shut and cuts off the
air entering the compressor.

If the pressure is high enough to cause
the diaphragm to hold the needle valve
open, and if the amount passing through
the needle valve is enough to keep the
cylinder full, and at the same time can
escape through the airports in the air
piston, the unloader will prevent the air
from entering the compressor. On the
other hand, if the pressure should fall
just enough to make the volume of air
raising the needle valve less than the

Indicated horsepower, steam, 126.

Indicated horsepower, water end, 118.

Mechanical efficiency, 93.6 per cent.

During the month of June, 1911, with
a load factor of only 50 per cent. I
pumped with this same unit an average
of 7000 gallons of water per gallon of
crude-oil fuel. The crude oil cost 4
cents per gallon.

J. F. Reynolds.

Phoenix, Ariz.

Small Machine Foundations

There are various ways of installing
machinery. Some men will put a ma-
chine on timbers set into the earth; some
will use brick foundations, but the cheap-
est and best foundations are built of
concrete.

The sketch shows a small blower rest-

DiAGRAM OF Humidifying System

shut, was relieved by drilling three j'j-
inch holes in the head of the piston.

This made it work between 2 pounds
variation but the piston soon ran dry
and the diaphragm became loaded with
moisture, oil and sediment.

All of this trouble was overcome by
turning the air cylinder and diaphragm
housing upside down and leaving the
regulator body in its original position. I
used the oil-cup connections for a blow-
off in case any sediment, oil or moisture
accumulated. The new connection for
the oil cup is on the air inlet to the dia-
phragm chamber, and the oil enters the
air pipe, lubricating whatever it comes in
contact with. This tends to keep a thin film
of oil around the point of the needle
valve and also around the piston and the
cylinder walls.

Once the piston is lubricated it is oil
packed, and having larger airports and
more of them, allows fhe air to exhaust
more freely; also, the regulator-valve
spring does not need any more tension
than is necessary to overcome the fric-
tion of the valve and cylinder. The air
comes down from the receiver just before
it enters the diaphragm chamber and en-
ters a scale and moisture pocket at the
bottom of the air pipe, as shown in fhe
illustration. About 8 inches from the
bottom there is a tee which leads to the
oil cup, then to the diaphragm chamber.

capacity of the airports in the air pis-
ton, the regulator-valve spring will force
the valve open. If the needle valve
should leak, air will escape through the
airports in the air piston. By adjust-
ing the regulator-valve spring a variation
of from '4 to 5 pounds can be obtained.
This could not be done before the change
was made; the device has now been
working satisfactorily for two months.
George Morton.
Southbridge. Mass.

Test of Pumping Engine,

It may interest some of the Power
readers to know of my latest pumping
unit, installed at the city municipal
pumping plant at Phoenix, Ariz., about
a year ago. Here it is:

Duration of test, 8 hours.

Size of engine, 12^x30x30 inches.

Size of water end, 13^x30 inches.

Revolutions per minute, 51.

Gallons per revolution, 70.4212.

Foot-pounds per hour, 233,787,457.

Steam used in 8 hours, 13,459 pounds.

Foot-pounds duty per 1000 pounds
dry steam, 141,214,380; line pressure
by gage, 47 pounds.

Suction lift in feet vacuum gage, 9.

Total head in feet by indicator dia-
gram, 130.19.

Mean effective pressure in water cyl-
inder, 56.5 pounds.

Concrete Foundation

ing on a concrete foundation built in box
form and having pockets on the interior
for the bolt head from the top. The
plugs used in forming the bolt holes taper
but by smearing them with black oil;
they easily withdraw, leaving a nice clean
hole in the foundation. A blower or
generator set on this kind of foundation
will last much longer than if bolted to
springing timbers with their constant vi-
bration.

C. R. McGahey.
Baltimore, Md.

A Pumping Problem

I am operating two 4S-inch double-
suction, engine-driven centrifugal pumps.
The engines are compound condensing
and run at 110 revolutions per minute.
When the river* is at medium stage the
pumps operate against an 8'1-foot head.

The engine governors are disconnected
and the engines operate with a fixed cut-
off. The curious thing is that the engines
slow down and the load on them in-
creases as the river rises and thus cuts
down th^ head.

Who can offer an explanation?

R. B. Crockett.

Canicetor. Texas.

December 19, 191 1

POWER

933

Unusual Arrangement of
Condenser

The condensing equipment shown in
the accompanying sketch is being in-
stalled in an Eastern power plant. The
installation is interesting as the layout
of the machinery as well as the piping
is unusual.

The prime mover is a 2(X)0-kilowatt
horizontal turbine with a 48-inch bottom-
exhaust connection to an 8000-square
foot, two-pass, countercurrent surface
condenser.

circulating pump is placed on the same
shaft as the wet-vacuum pump, both be-
ing driven by a turbine, the exhaust of
which is used for heating the feed water.
The circulating pump, having a capacity
of 5000 gallons per minute, is con-
nected to the water supply by a 16-inch
suction and discharges through a 14-
inch pipe to the condenser.

The dry-vacuum pump was placed on
the generator floor. A 5-inch suction is
divided into two branches, and connected
to the top of the condenser, one on each
side of the tube-supporting plate.

Z Priming

Circulating and
Condensing WaferPunifr^,-

'^^^7777777777^77777777777/7'

Arrangement of Condensing Outfit

An unusual feature is the placing of
the condenser in the generator room,
which was necessary on account of the
small headroom in the basement, the
distance from the floor to the ceiling
being only 6 feet 9 inches. The con-
denser flanges are 6 feet in diameter, so
for that matter it could have been placed
in the basement, but this would have
called for a side exhaust, which is much
inferior to a bottom connection.

The tube heads in the condenser were
too far apart, for the tubes to be left
unsupported, so the condenser shell was
cast in two parts and a tube-supporting
plate placed at the center line of the
exhaust inlet.

Another reason for splitting the con-
denser shell was the extreme difficulty
in casting a shell of that length in one
piece. To allow the tubes to expand
and contract, they were given a loose
fit in the supporting plate, expanded into
one tube head and ferruled into the other.
A 2-inch priming pipe with a valve con-
nects the steam space with the rear water
chamber of the condenser.

The condensing water is ta1<en from
the bottom of the condenser through two
4-inch pipes, one from each half of the
condenser shell. To fake care of any
condensation that would collect in the
exhaust pipe, a 4-inch connection was
made to the lower part of the exhaust
elbow. It became necessary to dig a pit
6 feet 6 inches deep in the basement
floor, as the distance from the lower
part of the exhaust elbow down to the
suction of the pump should not be less
than 4 feet.

As the sketch shows, the cenlrifucal

The equipment was designed for a
28-inch vacuum. A 5-inch gate valve
was placed on the suction flange of the
pump for testing purposes.

Gerhard Kelstrup.

Brooklyn, N. Y.

Isolated Plant Owners
Responsible

As far back as I care to trace them,
I have read articles in Power dealing
with the central station versus the iso-
lated plant. Nearly every writer believes
that the incompetence of the engineer in
charge is responsible for isolated plants
being taken over by the central station.

I desire to briefly consider other rea-
sons that have arisen in my own experi-
ence.

I believe that the owners or managers
of many isolated plants are as much
responsible for the poor economy shown
as their engineers. An engineer may
know that his plant is not running eco-
nomically, but if the "powers that be"
will not supply the necessary equipment
or make the needed changes or re-
pairs, I do not see how the engineer can
produce economical results; nor do I
think it fair to blame him if he cannot
produce good results from poor or in-
complete apparatus.

I ran a ccnain elcctric-liglitine plant
for some lime. The plant consisted of
an SO-horsepowcr boiler carrying steam
at 0.5 pounds gaRc pressure; an 86-
horsepowcr slide-valve automatic engine,
a .37'<-kilnwatf alternator with its ex-
citer and an arc machine carrying twenty-
six 2000-candlcpowcr open-arc lamps.

The load on the alternator averaged
about 15 kilowatts and the run was from
sunset to midnight, averaging about seven
hours the year around. To do this we
used about 40 tons of coal per month.
The water went to the boiler at a tem-
perature of about 85 degrees in summer
and from 50 to 75 degrees in winter. The
engine exhausted to the atmosphere
through a small closed heater that was
fitted with six 1-inch tubes which had
to take care of the exhaust from a 4-
inch pipe. A ^-inch bleeder from the
steam chest to the exhaust pipe was
kept partly open all the time and when
I put a steam gage on the exhaust pipe, it
showed 12 pounds back pressure.

I advised installing an open heater and
got figures on an outfit. With an ex-
penditure of $250 I could buy and install
an equipment that would reduce the fuel
expenses one-half. I presented the fig-
ures to the company and was promised
that they would take the matter up at
once; that was over three years ago. I
left the plant over a year ago and the
conditions are still the same.

hi another plant the manager buys the
oil. The engineer asked for another
grade of oil as the oil he was then using
was too light for that particular engine.
The manager informed him that he had
been buying oil and grease for over 30
years and that he knew what he wanted
as well as anybody. Yet it was neces-
sary to feed the oil almost in a stream
in order to keep the engine running
quietly.

Many men advocate as a means of
cutting down expenses the installation of
a CO. recorder, a draft gage and several
other instruments as well. All this is
good, but who is going to install them?
I do not think that very many engineers
of moderate-sized plants can afford to
buy them outright themselves and I do
not know of very many owners of small-
er medium-size plants who would spend
the money to get them; in fact, a man is
lucky to find a plant of this description
with enough tools to make the ordinary
repairs. Generally an engineer has to
carry a small machine shop with him
with which to run a plant after he does
get charge of it.

Now and then, instead of prodding the
engineers, although some of them may
need it, I would like to see a movement
started to stir up the managers and
owners of plants, especially of plants
where the central station is trying to
get in. Get them to take enough in-
terest and pride in their equipment to
at least cooperate with the engineer in
trying to get the beat out of the plant
that is pnssiljlc.

I know that if I have charge of a plant
and the owner will cooperate with me, that
there will be no danger of the central
station getting the job.

A. A. Blanchard,

Lecsburg, Fla.

POWER

December 19, 1911

> — i

Tail Rod Stuffing Box

The accompanying sketch shows what
I consider a better way of getting the
result described by Mr. McGahey on
page 705 of the November 7 issue.

By using a blind bonnet no packing is
required, and as the wearing surfaces are
large and can be well lubricated the
arrangement will relieve the eccentric of
s.ome work.

As the shoe wears down, it may be
turned around so as to bring another side
to the bottom, and as the holes in the
bonnet are interchangeable it also can
be turned around. A new oil hole will

The Tail Rod Stuffing Box

have to be drilled and the old one plugged
up. The bonnet can be made from a
piece of extra-heavy pipe and a suitable
flange and cap, with a brass bushing
driven into the pipe and peened. The
shoe is of steel.

The bushing should be short enough to
allow the shoe to travel over the ends and
not wear shoulders in it.

The bonnet may be covered with as-
bestos, with a sleeve made of sheet iron
to slip over it. This will reduce con-
densation and improve, the appearance.
Charles Bennett.

Chicago, 111.

Air Compressor Running
Under

In the October 31 issue, John S. Leese
shows four diagrams of air compressors
running under, and shows by arrows
the forces acting on the guides.

In Fig. I is shown a tandem machine.
The crank and crosshead are past the
center, the steam pressure is at about the
maximum and the air pressure is rising.
The engine has reached Jts maximum
speed for that stroke and is, therefore,
not storing any more energy in the fly-
wheels, so the force on the crosshead is
neither up nor down. But a little further
on in the stroke, the force is down, due
to the inertia of the flywheels, the in-

criticism, suggestions
and debote upon various
articks.letters and edit-
orials which have ap-
peared in previous
issues

creasing air pressure and decreasing
steam pressure. The flywheels must do
their work by pushing the crosshead dur-
ing expansion and over the dead centers.

In Fig. 2, two machines face each
other. The diagram shows the machines
in mid travel; the steam piston is under
maximum pressure and is pulling the fly-
wheels and air piston; therefore, the
pull is upward on both crossheads, and
remains so in every point of the strokes.

In Fig. 3 is shown a twin machine. The
pull on the crosshead is up on the steam
end and down on the air, running under
or the opposite running over.

James Johnson.

Hackett, Penn.

Leaky Corliss Valves

It is true, as J. O. Benefiel says on
page 750 of the November 14 issue, that
most, if not all, Corliss valves leak
more or less, and while I do not think
it is absolutely necessar>' that such valves
should be perfectly tight, I do think that
they could be better than found in most
places.

It is possible to so make Corliss valves
that they will not leak under pressures
met with in practice, but it would prob-
ably cost more than would be saved in
steam for quite a long time.

As generally fitted, the procedure is
like this: The valve chambers are bored
out to size, parallel and smooth, and if
ordinary care and skill are used, the'job
will be good so far as the chambers are
concerned.

Next, the valves are turned off in a
lathe to fit the chambers into which they
are to go. In my opinion, and from ob-
servation, the valves are usually turned
too small to make a steam-tight job. It
is thought advisable — and I believe it is
— to provide for Corliss steam valves lift-
ing from- their seats, in case of a dose
of. water getting into the engine cylinder.
This is usually accomplished by making
the valve a trifle smaller than the bore
of the chamber into which it is to go.
While it does not look as though it
would leak when fitted that way, yet it is

sure to do so. Some seem to think the
valves will wear down and become tight
but my experience has been that they
will not become tight when made and
fitted in the way described.

However, by turning the valve so that
it will be a tight fit in the cham-
ber, so tight that it cannot be rotated by
hand, and then easing off the upper semi-
circumference at each end of the valve
to permit the valve to lift from its seat,
as before referred to, a properly fitted
and practically steam-tight valve will be
had. In this case, the valve will wear
down tighter because it will have a
greater bearing surface to begin with,
which is lacking in the manner of fitting
the valves to which I first referred.

It is not an expensive job to ease off
the upper half of the circumference at
each end of the valve, and it is only at
the ends where the easing would have
to he done. I have tried this method and
got the best results from it.

Charles J. Mason.

Scranton. Penn.

Christie Air Steam Engine

I was interested in the discussion in
Power of the Christie air-steam engine.
About eighteen months ago one of my
clients asked for a report on the Christie
engine as he was thinking of investing
in some stock. After looking over the
prospectus, I wrote to the Christie com-
pany, telling them that there were some
gross misstatements in their literature.
They replied by sending me their latest
printed matter and inviting me to po'nt
out the misstatements, as the prospectus
had been out some time but had never
been criticized.

I called their attention to the fact that
they figured the efficiency of their engine

from the formula

T

which is, of

course, the efficiency of an engine work-
ing on the ideal or reversible cycle. Yet
they claimed this efficiency, which cannot
be obtained.

Further, in the diagram illustrating
the cycle of operations, it was made to
appear that atmospheric pressure was
made to do the work of exhausting the
working medium. As a matter of fact,
there is simply added an extra cylinder
in which the pressure on each side of
the piston is balanced; thus they have
simply added an extra piston which, must
be pulled along by the engine.

Then, the statement was made that the
compressed air in the end of the cylin-
der fills the clearance, as it is termed

December 19, 1911

POWER

935

and thus avoids the necessity of filling
the clearance with steam. "This elim-
inates steam-engine clearance loss." In
the next paragraph, Dalton's first law is
stated thus: "The pressure, and conse-
quently the quantity of vapor which
saturates a given space, are the same for
the same temperature, whether the space
contains a gas or is a vacuum." These
two statements are, of course, contra-
dictory, as it will take as much clear-
ance steam as if there were no air pres-
ent.

Further, Mr. Christie lost sight of the
fact that, when the steam valve opens,
the boiler, steam pipe and engine cylin-
der become one vessel and a rapid dif-
fusion of the air takes place into the
steam pipe; consequently the air pres-
sure in the cylinder drops during the ad-
mission of the steam and he does not
have all the air expanding in the cylinder
that was compressed there. Hence, for
a time at least, the engine must work as
an air compressor to pump air into the
boilers.

After a careful consideration of the
whole matter, I reported that, while a
mixture of steam and air has some
thermodynamic advantages as a working
fluid, they are probably more than offset
by the losses incident to the complicated
mechanism used by the four-stroke-cycle
air-steam engine to obtain them.

George L. Sullivan.

Bozeman, Mont.

Sand for Hot Bearings

The writer has read with considerable
interest the articles which have appeared
in the last few issues of Power under the
above caption and was amazed to learn
that there was more than one side to the
question. The rank and file in the vast
army of stationary engineers would, al-
most to a man, condemn sand in any
form in and about the engine room.

One writer, with a number of years
in the marine service to his credit, stated
in all sincerity that sand was considered
as much a part of engine-room supplies
on salt water as were oil and waste. An-
other man, equally as broad in his marine
experience, placed the first writer's story
on the shelf beside "The Classical Works
of Ananias" and "Autobiography of
Judas Iscariot," and with equal boldness
and sincerity stated that sand as a lubri-
cant was taboo on all occasions.

There may be times when sand is the
panacea for hot boxes, yet in all this
good-natured and highly appreciated con-
troversy, I do not recall that any of the
advocates of the sand treatment has ad-
vanced a theory or has given a reason
as to why sand will cool a hot bearing —
if it does.

If is a well known fact that the chem-
ical composition of various metals used
for both shafts and bearings, has much
to do with their running conditions. One

occasionally finds several bearings run-
ning under exactly similar conditions yet
with a wide difference in temperature.

The writer once observed a trouble-
man look over the bearing on a gen-
erator, the shaft of which was perhaps
6 inches in diameter. This bearing had
always run warm and the temperature
increased with time until it was neces-
sary to call in a man from the shop. He
removed the bearing and the shaft was
found to be as smooth and as perfect as
could be desired.

This, the expert claimed, was the real
trouble, it was too smooth, and much
to the surprise of those present he filed
the entire surface of the shaft in the
bearing quite liberally, and when the ma-
chine was assembled and again placed
in operation the bearing ran cooler than
it ever had done before. The expert
stoutly maintained that the shaft was so
smooth that the oil would not follow it
and the filing provided the necessary
means of lubrication.

Perhaps this is why sand is sometimes
a good thing for hot boxes, for the same
reason that lemon juice is good for a
sore throat. Let the adherents of the
sand treatment speak up. We would all
like to know the conditions under which
sand is used in bearings and the theory
advanced for its use as well.

GcoRCK H. Wallace.

Racine. Wis.

Show versus Efficiency

With the article by William E. Dixon,
"Show versus Efficiency," in the Novem-
ber 7 issue, I am heartily in accord. There
is, however, another side to this question
besides that of keeping the brasswork
polished. As is stated in an editorial in
the September 26 issue, the waste in coal
owing to this show is a very material
item; and while an attractive-looking
engine room and boiler room is a com-
fort to the eye, it is not always eco-
nomical. Polished brass or iron or
painted iron is not economical.

All piping carrying hot water or steam
should for the sake of economy be
covered with a nonconducting material,
even at the sacrifice of appearance. It
is not necessary that the effect should be
had or even poor, as pipe covering, if
properly installed, can be made to look
very attractive; and for the sake of sav-
ing not only labor for the employees but
coal for the owner, all pipes carrying any
amount of high-tcmpcraturc water or
«tcam should be covered, the thickness
depending on the temperature of the
pipes and the amount of radiation which
might come from them.

Particular attention should be paid to
covering all valves and all flanges, as
these sre far more effective as regards
dissipating heat than the plain pipe.
Henry D. Jackson.

Boston, Mass.

Water in Red Hot Boiler

In a recent number a correspondent
asked: "Will turning cold water into
a red-hot boiler cause an explosion?"

Anything that will cause a sudden local
change of temperature of any part of
a boiler will tend to strain that part un-
duly, due to sudden local contraction or
expansion. Whether an explosion will
be caused, either immediately or in the
future, will depend entirely upon the
condition of the boiler, the parts affected
by the strains and the damage done.

Allowing cold water to enter a hot
boiler is not an infallible test for ascer-
taining whether or not it would explode
in actual practice under like circum-
stances.

E. H. Bendel.

Chico, Cal.

Filling Oil Storage Tank

For the benefit of a few correspondents
who advocate using compressed air to
unload oil-tank cars, I submit this ex-
tract, from the notices sent out by the
Union Tank Line Company:

"Warning! Keep lights and fires away.
Air pressure must not be used in unload-
ing tank cars."

There is also other useful information
furnished on these notice cards, hut I
believe the above is all that pertains to
the point under discussion. In our case,
if we cannot empty the car in the usual
way, we use a pump and a suction line
with swivel joints, the joints being pro-
vided with stuffing boxes so that they
may be kept tight with packing.

E. H. Lane.

Kansas City. Mo.

Graft

I have read with interest the articles
appearing from time to time on the sub-
ject of graft. Some salesmen are so
clever as to lead a man into "deep
waters" before he realizes it. An experi-
ence which I once had illustrates my
point.

I was purchasing boiler compound from
a certain company, and as I do not smoke
I always refused the cigars offered by
the salesman. One day he said that he
was going to bring tnc a pocket knife,
stating that the company had some it was
distributing among its customers. Sup-
posing that it was a knife bearing the
company's name and advertisement. I
thanked him and told him it would be ac-
ceptable. When the knife came, to mv
surprise it was a nice little pearl-handled
affair which had been purchased at a
local hardware store.

Next he met me as I was going to
lunch, and insisted that I cat lunch with
him. which I could not very well refuse
to do. For Christmas I received a silver-
mounted brush. Several like courtesies
were offered, generally when itiy com-

936

POWER

December 19, 1911

pany was nearly out of the material he
was furnishing.

Other companies had been furnishing
some of the material, and this salesman
was anxious, to get all the business for
his company. He therefore set to work
to secure an advance order or contract
for a year's supply. He said:

"My sales for the last year amounted
to $12,500. The company has offered
to establish a branch office, putting me in
charge, if I will get $10,000 worth of
business this year. The price of the goods
we have been selling you is 6 cents per
pound; three packages would come to
$180. If you will give me an order for
three packages, I will make you a price
of 5 cents per pound. My commission
on this order will be $27. I am after
orders, not commissions, so that I may
get that branch office; if you will give
me this order, I will make you a personal
present of my commission."

Although I refused the offer, he in-
sisted that it was not a bribe but simply
a present from him; it was not the com-
pany's money.

R. L. Rayburn.

Kansas City, Mo.

I have been following with interest
the discussion on the subject of graft
which has been going on in Power.

There is graft in the sale of a good
many articles used in engineering, and
in many cases consulting engineers and
others in control of the purchase or use
of supplies and other materials are ap-
proached. Very often the selling concern
makes a price to the user which contains
a certain allowance for the "graft" or
commission to the party controlling the
purchase, and frequently the selling price
will not be reduced and no deduction will
be made if the grafting commission is
refused.

In dealing with a case of this kind,
insist that the commission be given in
the form of a check payable to order.
Then the recipient is in a position to pass
this check, properly indorsed, to the credit
of the purchasing concern and the fact
is recorded in such a way that no ques-
tion can ever arise. A further advantage
of this method of handling the matter
is that the indorsement upon the check
can be so written as to inform all who
handle it why it passed.

A. D. Williams.

Cleveland, Ohio.

I have read the various talks on
"Graft" that have appeared in Power
from time to time for the past year, and
I must say that I cannot believe that
there is anything to it, from what experi-
ence I have had. I have found very
little, if any, chance for an engineer to
do any grafting, as it is ab&iit all that
most of us can do to get what we actually
need for our plants.

Furthermore, an engineer would be a
fool to clKinge his satisfactory supplies

to an unknown line for the sake of a few
cents graft money. Take packing, for
instance; the average plant will not use
more than $25 worth a year. Can anyone
imagine any salesman fool enough to
give a great deal of graft money for the
privilege of furnishing such an amount,
or any engineer foolish enough to risk
his reputation and chances for such a
pittance as he would probably get out of
it?

I believe that if there are "crooks" in
the profession, they are after larger game-
than packing.

I have been an engineer for nearly 20
years and have never been offered a
bribe by any salesman for anything. I
have always found the salesmen to be
clever, upright men.

I never knew but one grafting engi-
neer, and the last time I saw him he was
pushing a small two-wheeled cart with
a sack on it, cleaning fertilizer off one
of our city streets.

D. W. Scarborough.

Richmond, Texas.

A Twenty Four Hour Log

In compliance with Mr. Ward's re-
quest in the issue of November 1, 1 sub-
mit the following calculations and sug-
gestions:

Assuming an average boiler pressure
of 120 pounds gage, with a feed-water
temperature of 274 degrees, the factor
of evaporation would be
p __ li - I + ?,^ __ 1 193-4 — ^74 + 3^
970.4 970.4

= 0.98
The equivalent evaporation per hour
would be

382,800 X 0.98

24

- = 15,631 pounds

from and at 212 degrees, which would
equal 453 horsepower developed with
the two boilers, or 226.5 horsepower per
boiler; this is 82.36 per cent, of the rat-
ing developed.

The coal aoparently runs about 9.2
per cent, ash, which, it may be assumed,
calls for a grade of bituminous coal of
about 13,170 B.t.u. per pound. To raise
one pound of water from 274 degrees to
the -boiling point corresponding to 120
pounds pressure gage, and evaporate it
into steam at the same pressure, requires
H —t + 32 = 1 193.4 — 274 -}- 32 =
951.4 B.t.u.

An evaporation of 1 1 pounds of water

per pound of coal as fired gives

11 X 951.4 = 10,465.4 B.t.u.

absorbed by the boiler per pound of coal.

The efficiency of the boiler and furnace

is then,

10,465.4

=79 per cent.

13,170 '^'

based on the coal as fired. This is higher

than the average.

Based on 12 square feet of heating

surface per horsepower there are

12 X 275 = 3300 square feet

per boiler, or 2.41 pounds of water evap-
orated per square foot of heating surface
per hour. According to the data given
there are 50 square feet of grate area per
boiler. Based on 50 square feet of heat-
ing surface to 1 of grate area, the boilers
would stand 66 square feet of grate area.

I believe that with this ratio of grate
area, and the installation of an efficient
mechanical stoker with a forced draft
of about 2 inches of water, Mr. Ward
should be able, with the high temperature
of feed water, to evaporate at least 12
pounds of water per pound of coal as
fired. Assuming that the peak load is
not greater than 550 horsepower, or 200
per cent, of builder's rating, this load of
462 horsepower, which would be an aver-
age of 168 per cent, of rating, could be
carried with one boiler, resulting in a
still higher degree of overall efficiency
and lower cost of operation.

This would require an average com-
bustion of about 20.2 pounds of coal per
square foot of grate area per hour. This
is not considered excessive with some
types of stoker, as the air supply neces-
sary to furnish the required amount of
oxygen for a practically complete com-
bustion is controlled automatically in
proportion to the coal delivered to the
furnace.

The electric load shows the plant to
be running at a load factor of only 10.4
per cent., which is not considered eco-
nomical operation; but there are cases
where a company's prospects of expan-
sion justify this loss. With the gen-
erator operating at 90 per cent, efficiency,
and the turbine proportionately efficient
in steam comsumption, I believe that Mr.
Ward has nothing to fear from the cen-
tral-station people. From my limited ex-
perience the results he is getting look
good.

J. L. Kezer.

Bradford, Penn.

Centrifut^al Pump Capacity
and Speed

In the issue of November 14, in a
criticism of an article by T. W. Hollo-
way on "Centrifugal Pump Capacity and
Speed," N. C. Hurst makes a gross error
when he derives the formula

/, = >':
<;

from that which he uses for centrifugal

force.

The original formula which he gives

for centrifugal force at unit radius and

with unit weight is correct. This formula

is F = — . The formula for the velocity

<7

of falling bodies is F = 1 2 g h. From
this, squaring both sides, V = 2 gh.
Substituting in the formula for centrifu-

2Qh

'al force we have F :

z= 2 ft. There-

fore. F — 2 h. and shows that "F is pro-
portional to" but that it is not equal to h.

December 19, 1911

POWER

937

From this it is evident that, from the
formula of centrifugal force, can be de-
rived 2h = — , or
9

H = '-

^ g

This formula can be derived directly
from the law of falling bodies.

Mr. Hurst speaks of the perfect pump.
The law of falling bodies applies exact-
ly to the "shutofF" pressure of the pump.
The working discharge pressure is de-
pendent upon many other factors, but
the pressure with the discharge closed
will follow the law accurately.

F. G. Wheeler.

Trenton, Mich.

Erticiencv of Reciprocating
Engines

A paper on the "Efficiency of Recipro-
cating Engines," by K. Heilmann, the
main features of which (translated from
the German) were published in Power
for October 31, is one of the most re-
markable contributions to our knowledge
of steam that has been published since
the days of Willans. These experiments
were made by a German manufacturer,
principally to compare the relative value
of the "uniflow" type of cylinder fitted
with poppet valves with the tandem-com-
pound type with piston valves, both using
steam of high pressure with high super-
heat, the tandem-compound engine hav-
ing the steam superheated a second tin:e
as it passes from the high- to the low-
pressure cylinder.

The notable features in these experi-
ments are the high pressures used, about
200 to 220 pounds, and a high degree
of superheating, reaching a temperature
as great as 930 degrees Fahrenheit. These
engines were of the "Locomobile" type
of construction, in which the engine,
boiler, superheater, condenser and punps
are all consolidated into one unit, the
steam cylinders being placed in the
smokebox of the boiler, or a continuation
of it, so that they are batiicd with the
waste gases as they pass out to the
chimney.

The tests were made under varying
conditions; the engines were operated
condensing and noncondensing, under
loads varying from about 60 to 150 indi-
cated horsepower; then with varying de-
grees of superheat, from 0 to over 500
degrees, and Finally with varying degrees
of vacuum. A valuable feature of these
experiments lies in the fact that they
have been conducted in a realm of pres-
sure and superheat which is outside of
usual practice, and th'refore point out
the direction in which it is possible to
work in securing superior economies. The
article as it appeared in Po»fr gives
most of the data of the original article
which was published in the Zeilsrhrifl
des Vcrdnes Dculsrhcr Ingenieur tor
June 10, 17 and 24, 1911.

It is interesting to note some of the
incidental features of these experiments,
which were not dwelt upon in the ab-
stract presented in Power.

It was found that in using high super-
heats that less difficulty with lubrication
was experienced with piston valves than
with the poppet valves of the "unifiow"
cylinder. In the "uniflow" cylinder the
steam valves were maintained at an ex-
tremely high temperature, the low pres-
sure and temperature steam passed out
through the center of the cylinder. With
the piston-valve engines the steam flowed
back through the valves at a lower pres-
sure and temperature than when admitted,
so that the average temperature of the
valves and seats was kept relatively low
pnd much below the temperature of the
initial superheated steam. It was found
that a residue from the burned oil was
deposited on the poppet valves and had
to be removed from time to time. This
residue was not found with piston valves.

In these experiments, both condensing
and noncondensing, the tandem-com-
pound engines developed a higher econ-
omy than the single "uniflow" cylinder
engine. On the other hand, the perform-
ance of the single-cylinder engine was
remarkable, and the practical benefits se-
cured by superheated steam were most
apparent in connection with this design.
One of the principal reasons why the
"uniflow" cylinder is less economical than
the compound was the fact that the ter-
minal pressures were much higher for
the same horsepower, so that more steam
at high tempercture was thrown away
into exhaust wititout doing any work.
It is interesting; to note that the steam
consumption with the "uniflow" cylinder
noncondensing was very uniform over a
great range of power, much more so
than is the case with the tandem engine.

Investigation of the strains developed
in both types of engine is recorded in
this paper. A "uniflow" cylinder 13.6
inches in diameter and a low-pressure
cylinder of one of the compounds 16
inches in diameter were taken for com-
parison. When working each at the same
piston speed under about 190 pounds
steam pressure the strains on the bear-
ings and frames of the "uniflow" engine
were about 2.4 times greater than on the
tandem engine developing the same
power. This means thai for the "uni-
flow" engine the pins, main bearings and
slides have to be much larger, and the
frame much heavier to withstand the
greater strains. Its flywheel also has
to be much heavier, as greater amounts
of work have to be absorbed and de-
livered by it.

In conclusion, these experiments show
that a steam engine can be opTated at
extremely high economy with a thermal
efficiency of the engine alone of about
26 per cent., and of the engine and boiler
together of 22 per cent. When it is re-
membered thai coal in most places fur-

nishes more heat units for a dollar than
any other form of fuel, it places en-
gines of this type in the front rank of
economical power-producing machines, a
brake horsepower-hour having been de-
veloped with an expenditure of only 12,-
000 B.t.u.

The writer is of the opinion that the
extreme temperatures used in these ex-
periments are experimental, and have
not been largely put in practice, but they
represent an advanced step in this di-
rection. In this connection it should be
remembered that engines of the locomo-
bile class have shown wonderful econ-
omies, with even less superheat, and high
economies have been secured with small,
as well as large, units. It would be ad-
vantageous if this article could be care-
fully translated throughout, so that every
professor of steam engineering should
be made familiar with it, as it throws
new light on the possibilities for the
steam engine. It would not be a bad ex-
ercise to give this article in the German
language to students, and have them
work out and tabulate the English values
with their slide-rules.

J. B. Stanwood.

Cincinnati, Ohio.

License Laws

Mr. Leiper's letter in a recent issue on
the Philadelphia license laws brings to
my mind similar laws in the city of De-
troit, Mich, .^bout a year ago, having
secured a position in that city, I went
to the city hall to be examined. The
clerk handed me a blank, which I had to
have signed by five engineers then em-
ployed in the city, stating that they knew
me, that I had had experience and was
competent as an engineer.

Now, if five engineers knew me, and
knew my ability and were willing to
swear to it, why did I need an examina-
tion or what did the examiner expect to
find out? Also, how could one get his
first papers if he could not get them
until five engineers knew his ability as an
engineer, when one was not allowed to
act as such? The ordinance was plainly
unconslilutional. but I had no friends or
funds to fight it. 1 was denied the right
of examination, notwilhsianding that I
held an Iowa and a Government license.

I hope some Detroit brother comes out
to defend the ordinance, because I want
to hear the other side of the matter.
I was informed that the engineers' union
was very strong. My idea of a union is
a body of men working to better condi-
tions and 10 educate rather than to shut
out competent men. Many city ordinances
arc drawn up by men who have not the
proper experience and for that reason a
union, to my mind, should try to remedy
such defects In city laws that arise from
Ibi"! cause.

Rnr V. HnwARP.

Tacoma. Wash.

938

POWER

December 19, 1911

Rnghie Horsepower

What is meant by the horsepower of
an engine? What is mean forward pres-
sure? What horsepower will an 11x24-
inch engine develop at 90 revolutions
per minute and 125 pounds pressure?
C. Z. L.
A horsepower is 33,000 foot-pounds
per minute.

The number of foot-pounds developed
by an engine per minute is the number
of feet passed through by the piston
multiplied by the average unbalanced
force; that is, the mean effective pressure
upon the piston.

The total mean forward pressure is
that quantity per square inch multiplied
by the area of the piston in square
inches.

The horsepower then is
Mean effective pressure X area X pistnn s peed
33.OO0
The area of an 11-inch circle is 95
square inches.

The piston speed of an engine with a
24-inch or 2-foot stroke running 90 revo-
lutions per minute is

2 X 2 X 90 = 360 feet
(2 feet per stroke, 2 strokes per revolu-
tion, 90 revolutions per minute).

The mean effective pressure is more
difficult to get. It depends not only upon
the initial pressure but upon the point
at which the steam is cut off, and upon
the bad: pressure, whether the engine is
run condensing or noncondensing, etc.
In a table of hyperbolic logarithms find
the logarithm of the ratio of expansion;
that is. of the number of times the steam
is expanded. Neglecting clearance, this
would be 4 for a quarter cutoff, 3 for
one-third cutoff, etc. Add 1 to the
logarithm and multiply it by the abso-
lute initial pressure found by adding the
barometric pressure to the gage pressure.
Divide the product by the ratio of ex-
pansion and the quotient will be the mean
forward pressure.

For example, suppose the ratio of ex-
pansion is 4, the hyperbolic logarithm of
which is 1.3863. Add 1 to this, making
2.3863. Suppose the barometric pressure
to be 14.7 pounds, the absolute initial
pressure would be

125 + 14.7 = 139.7
say 140 pounds. Then

^■386.^ X 140

7 — 03-5 pounds

Now what is the back pressure above
absolute zero? Suppose the' engine is

Questions arc^

not answered unless

accompanied by thej

name and address of ihe

inquirer. This page is

for you when stuck-

use it

noncondensing and has such compres-
sion that the average back pressure is
10.3 pounds above the atmospheric, mak-
ing an average absolute back pressure of

10.3 + 14.7 = 25 pounds
Take this from the 83.5 and 58.5 will
be had. This is what a perfect indi-
cator diagram within these limits of pres-
sure would give. One's own judgment
must be used in deciding how nearly the
engine in question would come to making
a perfect diagram. Knocking off 3.5
pounds for round corners, etc., and call-
ing the mean effective pressure 55
pounds, the horsepower would be

_ 55_X 95 X 360

33,000 ~"

up.

M^ater in Low Pressure
Cylinder

Under what conditions can the low-
pressure cylinder be wrecked with a jet
condenser?

E. B. M.

Suppose a condensing engine to be
running with the usual vacuum. If the
throttle valve be closed the engine will
make a few revolutions; there will be
a vacuum in the cylinder of the engine
just the same as in the condenser. Now
suppose the air pump to be stopped with-
out shutting off the injection water. The
water will fill the condenser and exhaust
pipe and enter the cylinder of the engine
through the open exhaust port. In the
cylinder it will meet the moving piston,
which cannot push all the water back
whence it came. When the exhaust valve
closes a certain amount of w^ater will
be entrapped within the cylinder, and as
the piston moved by the flywheel cannot
stop and the water in the cylinder can-
not be compressed, some part of the en-
gine must give way.

Lub7-iciitinir q;/ ;„ Boilers
What determines the size of a drop of
liquid? What might be expected to oc-
cur if lubricating oil is introduced into a
boiler with the feed?

A. B.

The volume of a drop of liquid is de-
termined by the size of the orifice, the
pressure, the temperature and its
viscosity. Lubricating oil introduced into
a boiler is apt to cause the seams, tube
ends and rivets to start leaking. A large
quantity of oil in a boiler will lodge on
the metal, preventing the water from com-
ing in contact with the surface affected
by the oil. If the boiler is forced a
bagged or blistered crown sheet or tube
will result.

Setting Valves on a Snow
Duplex Pump

How are the steam valves set on a
4K'x2i/ix4-inch Snow duplex pump?
R. J. S.
The steam valves on this type of pump
have no outside lap; hence in a cen-
tral position they just cover the steam
ports. It should also be remembered that
the piston on one side actuates the valve
on the other.

To set the valves, first move the pis-
tons to their extreme head-end positions
and mark the piston rods at the faces of
the stuffmg-box followers. Then place
the pistons in their extreme positions in
the other direction and similarly mark
the piston rods. Now make a mark on
the piston rods exactly half-way between
the first two marks and place piston No. 1
so that this center mark will come just
flush with the stuffing-box follower. The
piston is now at mid-stroke.

Take off the steam-chest cover of No.
2 cylinder, disconnect the link from the
head of the valve rod and place the
valve in its central position. If only a
single valve-rod nut is used, place this
mid-way between the jaws on the back
of the valve and screw the valve rod in
or out until the eye on the rod comes
in line with the eye on the link, then
reconnect.

If instead of the valve being moved by
one nut on the rod between the jaws,
two nuts are employed, one on either
side of the jaws, then these nuts should
be so adjusted as to allow about A inch
lost motion on each side of the jaw. Then
reconnect as before.

Piston No. 2 may now be placed on
center and No. 1 valve set in a manner
similar to No. 1.

In 1910. Pennsylvania employed 169,-

497 miners in its anthracite and 175.-
403 men in its bituminous mines, the
production per man in the former being

498 short tons in 229 days and in the
latter 825 short tons in 238 days.

December 19, 1911

POWER

939

Annual Meeting of Ameri-
can Society of Mechan-
ical Engineers

The annual meeting of the American
Society of Mechanical Engineers was
held at the Engineering Societies Build-
ing. New York, Dec. 5 to 8. In attend-
ance and in the interest and variety of
the papers presented it was fully up to
the high standard of recent years.

On Tuesday evening the retiring presi-
dent. Col. E. D. Meier, presented his ad-
dress, which dealt with "The Engineer
in the Future" and was abstracted in our
last issue. At the close of his address
he was presented with the portrait, a
photograph of which also appeared in our
last issue, the presentation being very
fittingly made by Walter M. McFarland.
The newly elected president, Alexander
C. Humphreys, was then introduced and
gracefully acknowledged the high tribute
which had been paid to him by his
predecessor and assumed the responsibil-
ities of the head of the society for the
coming year.

The company then adjourned to the
society's rooms, where the retiring and
incoming presidents received and a col-
lation was served.

The session of Wednesday morning
was largely devoted to the internal af-
fairs of the society. The net increase
in membership during the past year has
been 108. The officers announced as
elected for the coming year are: Presi-
dent, Alexander C. Humphreys, presi-
dent of Stevens Institute of Technology;
vice-presidents, William P. Durand, pro-
fessor of mechanical engineering at
Stanford University. Ira N. Hollis, pro-
fessor of engineering at Harvard Uni-
versity, and Thomas B. Stearns, of Den-
ver; managers. Charles J. Davidson, of
Milwaukee, Henry Hess, of Philadelphia,
and George A. Orrok, of New York;
treasurer, William H. Wiley, of New
York.

The usual luncheons were served in
the interims between the morning and
afternoon sessions, affording opportunity
for reunion and social intercourse.

On Wednesday evening the society was
favored with a lecture by Dr. Robert
Simpson Woodward, president of the
Carnegie Institution at Washington, on
"Ceo-Dynamics, or the Mechanics of the
Formation of Worlds."

On Thursday afternoon an invitation
was accepted from the White Star Line
to visit the "Olympic." the largest pas-
senger steamer afloat. On Thursday even-
ing a reunion was held at the Hotel
Astor in honor of the newly elected of-
ficers and visiting members of the so-
ciety and their ladies and guests, which
was attended by upward of seven htin-
dred.

On Friday a large number of the mem-
bers visited the Edison laboratories at

Orange, N. J., and numerous other ex-
cursions to points of local interest were
participated in by smaller groups.

The papers produced by the meeting
which will most interest Power readers
were those dealing with the test to
destruction of two 72-in. horizontal
tubular boilers, by James E. Howard,
and the remarkable test of two 2300-hp.
boilers at the Delray station of the De-
troit Edison Electric Co., both abstracted
in our issue of Dec. 5. the discussions
of which will appear later, and the pro-
ceedings of

The Gas Power Section

The session of the Gas Power Section,
held on Thursday morning, was char-
acterized by the presentation of four
highly interesting papers and a limited
discussion of two of them. The time
available was much too short for ade-
quate presentation and discussion.

Gas Power in 1911

The session opened with the annual
address by the chairman. Prof. R. H.
Fernald, in which the developments of
the year now closing were interestingly
reviewed. In the address, Prof. Fernald
pointed out that in Europe engines are
being built to develop 1500 hp. per cyl-
inder, working on the four-stroke cycle,
and 2000 hp. working on the two-stroke
cycle.

Referring to the European practice
in Diesel-engine construction, he said
that in Swiss electric stations there are
Diesel engines of 2000 hp. each. These
are. of course, multicylinder, but the
power per cylinder is increasing rapidly,
and "it will not be long before 1000
hp. developed in one cylinder will be
thought nothing extraordinary."

Regarding the utilization of waste heat
from the pas engine, he said that, al-
though exhaust-heal boilers are in sat-
isfactory use, it is the general opinion
that the most efficient method is a com-
bination gas and steam engine. In such
a combination the gas engine would be
made less efficient than normal by using
a lower compression than usual and run-
ning with less ignition advance. The
heat economy would go up to about 12,-
000 B.t.u. per brake horsepower, but the
steam boiler would utilize the increased
heat carried nut in the exhaust gases.
It is estimated that for each brake horse-
power developed by the ga • part of the
combination, 4 lb. of steam per hour
would be available from exhaust-heat
recovery.

The proposed steam cylinder wotild he
of the uni-direclional-flow ivpc. with ex-
haust ports in the center of the cylin-
der, covered and uncovered by the pis-
ton. For this type of engirrc. Prof.
Fernald said, an economy of 12 lb. of
steam per hnrsepnwcr-hour might easily
be obtained. Three- fourths of the total

output, therefore, would be due to gas
and one-fourth to steam. The combined
economy of the composite unit, he said,
would be as low as 9000 B.t.u. per brake
horsepower-hour.

Concerning what Prof. Bone terms
"surface combustion," Mr. Fernald said
that the latest report from this method
was to the effect that gas-fired boilers
have evaporated 21.6 lb. of water per
square foot of heating surface, showing
a heat-transmission efficiency of 94 per
cent. Deducting 4 per cent, to cover the
power required to supply the air pres-
sure leaves a net efficiency of 90 per
cent.

Referring to the crude-oil gas pro-
ducer. Prof. Fernald described briefly the
Grine apparatus,* which is the latest
development in that branch of the field,
and in conclusion, he said:

It is si'alif.ving to' note tliut eaeb .vo.1i'
• liniinntes maii.v of tlie absurd proplieclos re-
garding tbe eliminalinn -of practlcall.v all
prime movers siivc the Internnlcomliiistlon
engine, and that tlio past .rear lias lieen on< of
slead.v. conservative progress .lud develop-
ment in the- lield lliat Is of such keen In-
terest to so large a percentage of the total
mrmliership of the .American Society of Me-
ch.TnUal Knfrineers.

The first paper of the session was by
H. R. Setz, and bore the somewhat am-
bitious title of "Oil Engines." The author
reviewed the development of oil-engine
design, describing briefly the salient fea-
tures of the various types of oil en-
gine, from the early Hornsby-Akroyd up
to the latest Diesel. His review led up
to a special form of engine designed
by himself to work on the Diesel cycle.
The paper will be abstracted in an early
issue.

Following the presentation of Mr.
Setz's paper, one by Forrest M. Towl
was read in which the results of a test
of an 85-hp. De La Vergne oil engine
were given. This paper was printed al-
most in full in the Gas Power Depart-
ment of Power for Dec. 12.

Discussing Mr. Setz's paper, H. .1. K.
Freyn pointed out the fact that since
the expiration of the Diesel patents, most
of the important engine builders in
Europe have taken up its manufacture,
with the result that prices have been ma-
terially reduced. A certain four-'cylin-
dcr engine built in France sells for
S45 per horsepower, in sizes of 1000
hp. and over. He pointed out a1«o that
part of the explanation of the lower
prices in Europe is the fact (hat skilled
labor is cheaper there than here and also
of a higher grade, by reason nf the much
greater number nf years of experience.

Mr. Freyn counseled moderation In at-
tacking the oil-engine problem and ex-
pressed the opinion that marine work
will probably afford an Immc.se field for
oil power, because of the compactness
of fuel and equipment, wh.ch increases

940

POWER

December 19, 1911

the radius of action per unit of fuel-
storage capacity and power-plant space.
Referring to the matter of fuel econ-
omy as between oil engines and pro-
ducer-gas power plants, L. B. Lent
pointed out the fact that geographical
location has much to do with the relative
economy; where oil is cheap coal is
usually high, and vice versa. He pre-
sented the accompanying table showing
the comparative prices of oil and pro-
ducer-gas power, based on the consump-
tion of '/. lb. of oil and 1 lb. of coal per
brake horsepower-hour, and the same
cost per unit of work for both kinds of
equipment.

I.KNT'.S TABLE OF HOMP.'V.H.'VTIVE COSTS

Fuel Cost Equiva-

Cost of P«r Brake lent Cost

Oil per Horsepower- of Coal

Callon hour per Ton

2e. 0 l.'ioc. S3 10

2 J 0 174 3 19

2* 0 194

2J 0 213

O 233

3i
3i
3

0 2i>2
0 271
0 2'.)0

4
4i
4i

■li

0 310
0 330
0 349

0 33S

4.26

4 6.5

r, 03

6.20
6.58
6.97

In closing the discussion of the oil-
engine papers, Mr. Setz explained, in
response to a question by Charles W.
Baker, that the temperature of the in-
jection air falls when the air enters the
cylinder, and this is one of the diffi-
culties encountered in building engines
to run on heavy oils. This drop in the
temperature of the injection air, upon
entering the cylinder, is so great in some
cases, he said, that it is difficult to ignite
the oil, even at full load. One of the
solutions of this problem, he stated, is
to use light oil to produce ignition and
follow it with a charge of heavy oil. Mr.
Setz corroborated Mr. Freyn's assertion
that the quality of workmanship in this
country is, as a rule, not as high as in
Europe. The manufacture of oil engines
of the Diesel class, he said, requires
greater precision in both machinery and
men than is commonly found here.

The next paper was one by Prof. W.
1). Ennis, on "Design Constants for
Small Gasoline Engines." This related
to automobile engines and was too mathe-
matical for satisfactory abstracting. One
of the features of the paper was the
proposal of the formula:

Cd-iso.9 „ , ,

= liiake horsepower

24,300,000 "^

in which

d = Piston diameter;

/=rA number (1.85 suggested);

S= Piston speed, feet per minute;

C = A "constant," ranging from
5970 to 11,008 in value.
There was no oral discussion of this
paper, and Edwin D. Dreyfus then pre-
sented, in abstract, a paper on the "Tests,
Construction and Working Costs of a
1000-kw. Natural Gas Engine." prepared
by himself and V. J. Hulquist. The

paper contained a brief description of a
generating unit in the Allegheny plant of
the American Locomotive Co. The en-
gine is a twin tandem double-acting ma-
chine, with cylinders of 23 'j in. bore and
33 in. stroke, rated at 150 r.p.m. The
test showed a heat economy of 10,410
B.t.u. per brake horsepower-hour, at 81 ^<
per cent, of rated load and at 1.7 per
cent, above rated load, using natural
gas of about 1050 B.t.u. per cubic foot.
The mechanical efficiency of the engine
was 68 to 80 per cent., according to the'
load; the lowest figure was obtained at
724 brake horsepower and the highest
at 1220. At about full-load rating the
mechanical efficiency was 78.2 per cent.
With one half of the engine "dead" and
being dragged by the other half, in ad-
dition to a brake load of 370 hp., the me-
chanical efficiency went down to 65 per
cent. The average speed variation, from
no load to full load, was 3.1 per cent.

The construction cost of the plant was
only 880.18 per kilowatt of capacity, in-
cluding the 1000-kw. generator, switch-
board, building, land, etc. The total op-
erating costs, including fixed charges,
are given as below:

Cost per Kilowatt-
hour, Cents
10-hr. Day 22-hi. Day

Half load 1.263 0.8.59

Three-quarters 0.907 0.637

Full load 0 . 742 0 .536

Discussing Messrs. Dreyfus and Hul-
quist's paper, Mr. Moultrop remarked on
the low cost of the plant and said that
it was much lower than figures with
which he had become familiar through
his work on the plant-operation com-
mittee. Mr. Freyn said that his experi-
ence had been that a large blast-furnace
gas-engine plant could be installed for
S90 or less, including the cleansing out-
fit, which usually costs about SIO per
kilowatt of power-plant capacity.

Fate of Polytechnic Institute
in Balance

For many years the institute, like many
technical schools, has been operated at
a loss, which has amounted to about
SIOOO per week. This deficit has been
made up by the generous contributions
of public-spirited men who have con-
stituted the board of trustees. It has
been proposed to raise a fund of S800,-
000, which would relieve all indebted-
ness and provide an income sufficient to
care for the usual running expenses. Of
this sum S520,000 has been conditionally
subscribed by the trustees themselves;
an additional $130,000 has been raised
by subscription on the part of the citizens
of Brooklyn.

To get this $650,000 already subscribed,
SI 50.000 more must be given by Jan. 1.
This probably means that the sum must
be made up in small contributions from
a large number of persons interested.
The man who pledges himself to give

$187.50 before Dec. 31, 1911, will be
virtually endowing the Polytechnic with
$1000.

The Polytechnic is doing good work
in New York. It affords the opportunity
for men to obtain in their evening hours
precisely the same sort of high-grade
technical education that the son of
wealthy parents can obtain by the usual
four years' undergraduate course. It is
hardly conceivable that the engineers of
New York will allow such a meritorious
work to fail for lack of funds.

The National Gas Engine
Association

At its annual meeting, held in Cleve-
land, Ohio, Dec. 5 to 8. the National Gas
and Gasoline Engine Trades Association
changed its name to the extent of omit-
ting the words "and Gasoline" and
"Trades," the result being as in the
above heading.

The officers elected for the ensuing m

year are O. C. Parker, of La Crosse, "

Wis., president; H. W. Jones, of Chicago,
vice-president; Charles O. Hamilton, of
Elyria, Ohio, H. W. Bolens, of Port
Washington, Wis., and O. B. lies, of
Indianapolis, Ind., members of the ex-
ecutive committee.

The meeting next June will be held in
Milwaukee.

Liverpool Explosion i

As often happens in the first dispatches I

of a severe accident, the loss of life
in the recent Liverpool explosion is 23
instead of 33 persons, while the injured
number 70 instead of 100, as stated in
the Dec. 5 issue.

The cause is now attributed to the igni- J

tion of a mixture of dust and air rather I

than to a boiler explosion, as at first '

reported.

It appears, says the Manchester Guard-
ian, that the atmosphere in the room was
heavily charged with floating dust pro-
duced by the grinding of dry kernels,
seeds or husks from which the oil had
been expressed. A spark from a piece
of metal trapped in a grinding machine
might set fire to such a mixture, or it
might be ignited by some accidental
sparking in the electrical equipment, thus
causing the violent explosion, which was
accompanied by enormous sheets of flame,
the hurling of heavy machinery from
its place, and the rapid collapse of the
building. Within the last few years the
danger of dust explosions has been fully
recognized in the case of coal mines, and
it is very probable that even yet the
imflammable character of other kinds of
dust, such as are produced in many man-
ufacturing processes, has not received
due attention. Such lessons are, un-
fortunately, too often taught only by
dreadful experience, as instanced in the
Bibby & Sons oilcake mills.

Vol. 34

NEW YORK, DECEMBER 2b, 1911

No

We Hereby Offer a Prize of Fifty Dollars Gold

to the man who, before March i, 19 u, sub-
mits the best practical article on

" Running aSteamTurbine"

These gentlemen have consented to pass upon
the merits of the articles submitted and to
decide who is entitled to the prize :

HENRY G. STOTT

Superinlendcnt of Motive Power,
Interborough Rapid Transit Co., New York

JAMES D. ANDREW

of the Boston Elevated Railway Company

ORLAFF E. OLESON

Chief Enginef-r, KLsk and Quarry St. Station
of the Commonwealth Edison Company of Chicago

WHAT would you do, you who
have never seen a steam tiu"-
bine except in a picture-book,
if you were led alongside a machine
like one of these and told to run it? Would you know
what precautions to take before you opened the throt-
tle? Would you know the purpose of the various
valves and levers about it? Would yoti know what
to jump for if anything went wrong, what to look out
for to prevent anything from going wrong? Could you
diagnose impending trouble from its first symptoms and
stave it off? Could you take a machine which would
not stay packed and find out why, and pack it to stay?

The three manufacturers of large turbines in the
United States have put out some five milhon kilr)WiiUs
capacity, mostly within ten years, and the bulk of
this in the past half dozen years. If present indi-
cations hold,
there will be
a greater in-
crease in the
next half
dozen years.

There will
be men neefl-
e d t f) run
these tur-
bines.

Meu will not be needed to rmi the
piston engmes which they will displace.

The stationary engineer who wants
to keep uj) with the times, who wants
to be in a position to take advantage
of olTering opj^ortunities and grow with
his years and with the progress of his
vocation, must learn about steam
turbines.

Most of the available literature
upon the subject deals with principles,
with type differences, efficiencies, etc.
There is little or nothing in print to
tell a man how and why a turbine
runs, and how to make it nm and
kee]) it running; how to .start it up
without distorting the disks or the
casing so as to cause the blades to
interfere; how to ad'ust clearances, the management
of the step in the vertical type; the function of the
bypass valve between stages, the care of the oil-circu-
lating and cooling system, the means taken to hold
glands tight against twenty-nine inches of vactmm.

The ])rize article will be jirinted in Power as such and
paid for at the regular rate in addition to the prize m:)".ey.
Such of the other articles as contain points not
brought out in the paper which receives the prize,
may be used in Power in whole or in part, and
tiuir authors recompensed in accordance with the u.se
made of them.

The articles will l>e judged not upon their literary

merit, but
by their
practical val-
ue to the man
of a v c r :i g e
edticilionand
inlrll igencc
who w.ints 1<»
I' :irn how to
inti n steatu

942

POWER

December 26, 1911

NewGeneratingStation,Portland,Ore.

Portland, Ore., with its population of
over 207,000, is supplied with light and
power by the Portland Railway, Light
and Power Company. Probably in no
better way can the marvelous growth of
the electrical industry in Portland be
shown than by comparing the city's
present consumption with that of 10
years ago. There were 1960 users of
electric light, and approximately 100
consumers of electric power, in 1901; on
January 1, 191 I, there were more than
27,000 customers for light and power,
the connected motor load totaling 28,000
horsepower, and the lighting load ex-
ceeding the equivalent of seven-hun-
dred thousand 16-candle-power lamps.
In addition, there are over 15,000 elec-
tric irons in use.

The territory covered, as shown in
Fig. 1, which also gives an idea of the
high-tension distributing system, is
served by three steam plants, sixteen
substations and four hydroelectric
plants, having a total rated capacity of
54,000 kilowatts and feeding an area of
approximately 856 square miles.

During the greater part of the year
about 95 per cent, of the demand is
taken care of by the hydroelectric
plants, but at such times of the year as
the water in the Willamette and Clacka-
mas rivers is low, the steam auxiliary
plants are called into service. For this
reason, and also in case of trouble on
any one of the high-tension lines, these
plants are always kept ready for imme-
diate service. In this connection the
economical use of fuel would be of
utmost importance were it not that
during the greater part of the year
sawdust is available as fuel. However,
station attendants must be at hand or
within call at all times, but as each of
the generating plants has substation
equipment the duties of the operators
are twofold; with the fire-room force
thi- r.oes not apply.

Station L

To handle the increased summer load
it was necessary last year to further
supplement the hydroelectric plants by
the construction of station L, located in
East Portland, within a short distance
of the heart of the city, and on the Wil-
lamette river. Its proximity to the river
makes available the required water for
condensing purposes.

On account of the unstability of the
ground, it was found necessary to drive
over .■'000 piles, spaced at 3- foot centers;
many of these were spliced and driven
to a depth of over 150 feet. After the
butts of the piles had been sawed off
to a uniform level, a concrete slab was
placed over them to a thickness of 3
feet, reinforced with a network of 50

By Edward A. West

A 6ooo-k I lotvatf. plant
confaiitiiig hvo turbogenera-
tors and one engine-dnvcn
■unit.

The former generate al-
ternating current at 2300
and 11,000 volts for light-
ing and long-distance trans-
mission, and the latter
direct ctirrent at 625 volts
for railway service.

tons of .>'4-inch steel bars. Fig. 2 shows
the piles after being sawed off, ready
for the concrete. To arrest the settle-
ment of the foundations (where they

by a fill of about 80,000 cubic yards of
gravel, sand and loam.

This fill was carried up to the level
of the station floor and extends west
about 40 feet, sloping out to the harbor
line of the river, and south about 300
feet across an old slough. On the east
side of the station the fill is carried level
over all the slough, and to the adjacent
banks within about 1 foot of the eleva-
tion of the station floor, which is equiva-
lent to 32" J feet above the low water
of the river. This fill, by confining the
fluid masses, has equalized the pressures
and practically stopped all settlement.

Recently test sheet piling of I-beam
and lock-bar type was driven, it being
thought that with a tight steel casing in-
closing the quicksand belt, all further
shifting of foundation material would be
stopped. This is a matter of much im-
portance, as serious results might en-
sue should any dredging be done in the
harbor.

Fig. 1. Map Showing Distribution System

rested on a quicksand belt about 20 Building

to 30 feet thick, and from 50 to 65 feet Preliminary plans for this station were

below the floor of the station) the sta- drawn by the company's engineers, and

tion foundations had to be surrounded the final and working drawings were

December 26, 1911

made by E. ^X^ Clark & Co., of Phila-
delphia, the best features of both sets
of plans being embodied in the design
of the station.

The building itself is 160x130 feet.
and of rein forced-concrete and steel
construction with brick gables and a
brick side wall on the north to allow

POWER

943

room. A double-track railway trestle are set in batteries of two each, with a

runs from the sawmill of the Inman- passageway between each battery. A

Poulsen Lumber Company to the storage space 20 feet wide between the two mid-

^'"- die batteries is occupied by two !7x

Fig. 2. Foundation Piling

for extension. An exterior view of this
is shown in Fig. 3. There is also a
lI2x54-foot wooden storage bin of mill
construction, for sawdust, located outside
the station at the side nearest the boiler

Exterior View of Plant

Boilers
The boiler room contains eight Bab-
cock & ^X'ilcox boilers, each ha\ing a
guaranteed evaporation of 30,000 pounds
of water from and at 212 degrees. They

E3?

10xI5-inch Worthington outside-packed
plunger feed pumps, fitted with Fisher
governors. .Above the feed pumps are
two Hoppes feed-water heaters, which
utilize the exhaust steam from the auxil-

944

POWER

December 26, 1911

iaries and the feed water dischargee
from the pumps through two Green
economizers.

A supply tank having a capacity of
approximately 10,000 gallons is located
above the heaters. The condensation
from the condenser hotwells from the
main units and make-up water is mea-
sured by means of four Hammond
meters, and each boiler is fitted with a
Copes feed-water regulator to maintain
a constant water level.

The furnaces, as shown in Fig. 6, are
designed with large dutch ovens, the
grates having an area of 148.7 square
feet, or a ratio of grate area to water-
heating surface of I to 27.5. The saw-
dust fuel is fed automatically by two

them to the burners by means of two
Knowles steam pumps equipped with
Witte regulators for maintaining a uni-
form pressure of 50 pounds. An auxili-
ary feed pump is also provided for mak-
ing tests on the boilers and for washing.
This arrangement of boiler-room
equipment has proved very economical,
5.04 kilowatt-hours per gallon of oil hav-
ing been attained under actual running
conditions.

Prime Movers

The engine room, with the balcony for
oil switches, transformers and electrical
equipment (see Figs. 5 and 8), is so ar-
ranged that everything is controlled from
the main floor, thus doing away with the

tions of the turbines are cored out and
the condensers and hotwell pumps are
set directly underneath.

The condensers are of the Alberger
surface type; the one for the engine
having a capacity of 50,000 pounds of
steam per hour and the other two, 55,-
000 pounds each. Separate dry-vacuum
pumps of the steam-driven flywheel
type are provided for each condenser.

The hotwell pumps are of the Al-
berger simplex valveless pattern, and
circulating water is supplied by three
centrifugal pumps of R. D. Wood make,
two with 16-inch suctions for the tur-
bines and one with a 14-inch suction for
the engine. These pumps are located in
a tunnel and are driven through vertical

Fig. 5. Gi n

,iNE Room

conveyers which bring it from the
storage bin.

At the rear of each boiler is a three-
panel Hammel oil burner, fitted with
checkered grates and draft doors for
regulation. The arrangement is such
that a combination of both fuels may
be used at one time or either may be
burned separately.

There are four storage tanks for oil,
located underground and about 80 feet
from the station. Two of them have a
capacity of 5000 barrels each, and the
oil is pumped from them into smaller
ones of 500 barrels capacity each, by a
motor-driven plunger power pump. The
oil used during each watch is measured
in the smaller tanks and is pumped from

necessity of running up and down stairs.
There are at present installed two four-
stage, condensing, horizontal, Curtis
turbines running at 1800 revolutions per
minute, one connected to a 2000-kilo-
watt, three-phase, 60-cycle, 11, 000- volt
generator and the other to a 2000-kilo-
watt, three-phase, 60-cycIe, 2300-volt
generator. In addition to the turbine
units there is a 34x68x54-inch hori-
zontal cross-compound condensing
Hamilton Corliss engine running at 90
revolutions per minute and direct-connect-
ed to a 2000-kilowatt, 625-volt, direct-cur-
rent generator; this unit is for railway
service. Space is provided for a fourth
unit which will probably be a 5000-
kilowatt horizontal turbine. The founda-

shafts by motors located on the engine-
room floor. The suction pipes are carried
under the concrete mat in a tunnel hav-
ing a bulkhead at the river end; the
discharge tunnel lies beneath this at an
elevation which always insures a suffi-
cient seal and the condensers discharge
into this tunnel through a hole in the
mat.

The exciting current for the turbo-
generator sets is supplied from one ex-
citer set consisting of an llxl2-inch
Skinner automatic engine, direct-con-
nected to a 125- volt Allis-Chalmers
generator. There are two I0x30-inch
Allis-Chalmers Corliss engines, which
drive two 18-foot induced-draft fans
which maintain a draft of 0.6 inch when

December 26, 1911

POWER

945

sawdust is burned alone. They are not
used, however, when oil is burned, as
the natural draft of about 0.3 inch is
sufficient to secure complete combus-
tion with this fuel. The stack, which is

lower 50 feet of this stack is cored out
with 4-inch air spaces for cooling.
Auxiliary Equipment
In addition to the foregoing equip-
ment there are a fire pump, a centrifugal

n'-9i'

ferent voltages, namely, 11,000 and
2300. There are duplicate sets of bus-
bars for ecch voltage and between these
is a bank of transformers, making it
possible to feed either or both the 11,000-
volt and the 2300-voIt busbars from
either of the alternating-current gene-

Section through Boiler Setting

shown in Fig. 7, is of concrete 'nd of
the Webber patent type, 125 fee' r.igh,
with an inside diameter of 12 feet. '' hj

pump for make-up water, pumping di-
rectly from the river, air compressors
and other small auxiliaries which go to
make this station one of the most modern
and best equipped plants in the North-
west The extensive use of recording

Fig. 7. Concrete Chimney

rators. This affords a very flexible
arrangement.

Fig. 8, represents the II, 000- volt
switching equipment. In this case, as
with the 2300-volt equipment, duplicate
busbars are installed. Each feeder and

Fig. 8. Showing Switch and Busbar
Structure

Fig. p. 230n-voLT Bi'^baR'!

thermometers and gages cnablet the
operating force and those directing 'hem
to obtain very accurate and valuable
records of the operating conditions.

Electrical Equipment

As previously mentioned in the
description of the generators, the alter-
nating current Is generated at fw) dif-

llG. 10. 1 l,iH)(I.V(ii t Oii-<;mitch Gov-
paktments

machine is connected to both busbars
through two sets of disconnccing
switches and motor-operated oil switches,
allowing any switch to be cut clear of
the hu«har?. feeders or machine!" for
repairs without interruption to the ser-
vice. Through the remote control the
operator may open or close any of
the oil switches while standing in

946

POWER

December 26, 1911

front of the switchboard, thus saving
time and confusion in case of trouble.
Asbestos board barriers have been used
to advantage above and between the dis-
connecting switches.

The means of supporting the switch-
board have proved of great advantage;
instead of bracing from the wall to the
top of the board the supports run at
an angle from the top of the board to
the I-beams of the balcony floor above;
this makes a more rigid construction, be-

sides giving more clearance back of the
board. The pipe supports of the switch-
board are entirely clear of the ground,
making it impossible for a man work-
ing on the back of the board to short-
circuit with the ground.

The 600-volt railway system has been
worked out along the lines of ordinary
practice, the neutralizing being done on
the negative side.

The switchboard panels are all of the
standard General Electric type, auto-

matic breakers being used on each
railway feeder. In the case of each
of the 2300-volt alternating-current
power and lighting feeders, automatic
induction regulators are installed.

All control and lighting wiring is run
in metal conduit concealed in the station
walls and floors, and the machine and
high-tension cables are run in clay and
fiber ducts enveloped in concrete,
giving the whole a concrete-beam
effect.

Massachusetts License Law Revised

Several important changes have been
made in the Massachusetts engineers'
and firemen's license law. to take effect
Jan. I, 1912.

Under the old rules any engine over
8 hp. (exclusive of those under federal
jurisdiction, on road vehicles or in private
residences) must be in charge of a li-
censed engineer. This has now been
changed to apply to any engine over 9
horsepower.

Section 80 has been amended so as to
include a designation of the terms "op-
erate," "operated" or "operating," where
used in the law, as applying to any per-
son who, under the supervision of the
licensed person in charge, operates any
appurtenances of a boiler or engine;
provided that there is not more than one
such person employed for every licensed
person and that any such operating must
be in the presence of and under the
personal supervision of the latter person.

That part of section 81 which pertains
to the application for licenses has been
changed so that the applicant must ap-
ply to the state inspector of boilers for
the city or town in which he resides in-
stead of to the examiner of engineers
for the said town or city. 'Also, the ap-
plication blanks are to be obtained from
the boiler-inspection department of the
district police instead of the blanks be-
ing furnished by the examiner. In this
section the requirements for examination
are now set forth definitely as follows:

"To be eligible for examination for
a first-class fireman's license, a person
must have been employed as a steam
engineer or fireman in charge of or op-
erating boilers for not less than one
year or he must have held and used a
second-class fireman's license for not
less than six months. To be eligible for
examination for a third-class engineer's
license, a person must have been em-
ployed as a steam engineer or fireman
in charge of or operating boilers for
not less than 1 ' '■ years, or he must have
held a first-class fireman's license for
not less than one year. To be eligible
for examination for a second-class en-
gineer's license, a person must have
been employed as a steam engineer in
charge of a steam plant or plants hav-

Important changes Jiave
been made in the applica-
tion for examination, and
in an appeal therefrom;
also the boiler-horsepo'd'er
rating has been altered
slightly and a turbine rating
appended.

Additional changes of
minor im,portance are point-
ed Old.

The amended rules take
effect Jan. i. ii;i2.

ing at least one engine of over 50 hp.
for not less than two years, or he must
have held and used, a third-class engi-
neer's license for not less than one year,
or have held and used a special license
to operate a first-class plant for not
less than two years; except that any
person who has served three years as
apprentice to the machinist or boiler-
making trade in stationary, marine or
locomotive engine or boiler works and
who has been employed for one year in
connection with the operation of a
steam plant, or any person graduated
as a mechanical engineer from a
duly recognized school of technology,
who has been employed for one year
in connection with the operation of a
steam plant, shall be eligible for ex-
amination for a second-class engineer's
license. To be eligible for examination
for a first-class engineer's license, a
person must have been employed
for not less than three years as a
steam engineer in charge of a
steam plant or plants having at least
one engine of over 150 hp., or he must
have held and used a second-class en-
gineer's license in a second-class or first-
class plant for not less than 3'i years.
The applicant shall make oath to the
statements contained in his application,
and the members of the boiler-inspection
department are authorized to administer
the oath."

The old rules provided that if an ap-
plicant successfully passed the examina-

tion a license should be issued to him
within six days after the examination.
This time limit has been omitted in the
amendments. Furthermore, they provide
that an applicant for a first- or second-
class engineer's license, or for a special
license to operate a first-class plant, or
for a special license to have charge of
a second-class plant, shall be examined
by a board of three examiners, one of
whom may be the chief inspector; and if
the applicant is employed, one member
of the board shall be the state inspector
of boilers for the city or town in which
the applicant is employed.

Formerly a license remained in force
for three years or until revoked for in-
competence or untrustworthiness. Under
the new rules a license shall remain in
force indefinitely unless suspended or
revoked for incompetence or untrust-
worthiness, except that a special license
shall not remain in force after the holder
ceases to be employed in the plant speci-
fied in the license. Also, a person whose
license is suspended or revoked shall
surrender his license to a member of
the boiler-inspection department. If a
new license of a different grade is is-
sued the old license shall be destroyed
by the examiner.

Under the heading "Classification
of Licenses" have been added two
new classes — a "portable" class and
a "steam fire engineers" class, the
former applying to a person having
charge of or operating portable boilers
and engines, except hoisting engines and
steam fire engines, and the latter apply-
ing to one who has charge of or operates
a steam fire engine or boiler.

A change has also been made in the
boiler-horsepower rating, it being deter-
mined upon the basis of 3 hp. for each
square foot of grate surface or its equiva-
lent, when the safety valve is set to blow
at a pressure exceeding 25 lb. per square
inch, and upon the basis of 1 ■ < hp. for
each square foot of grate surface or its
equivalent when the safety valve is set
to blow at 25 lb. per square inch or less.

The reciprocating-engine horsepower
remains the same, but a turbine horse-
power rating has been added. This is to
the effect that a turbine engine shall

December 26, 1911

POWER

947

be rated at less than 9 hp. when the ex-
ternal diameter of the steam-supply pipe
does not exceed l-}4 in.; at 50 hp. when
the external diameter of the steam-sup-
ply pipe exceeds \H in. and does not
exceed 3;< in.; and at 150 hp. when the
external diameter of the steam-supply
pipe exceeds 3y< in. and does not ex-
ceed 5 inches.

Section 84, dealing with the right of
an applicant to appeal, has been changed
considerably. An appeal must now be
made to the chief inspector of the boiler-

inspection department, who shall appoint
three members of the boiler-inspection
department to act together as a board
of appeal, one of whom may be the
chief inspector (instead of appealing, as
formerly, to the remaining examiners,
three or more of whom acted as a board
of appeal*. Also, under the new rules
an appeal must be made within one
week (instead of one month) after the
decision of the examiner, and the ap-
plicant has the privilege of having one
first-class engineer present during the

hearing of the appeal, but the latter must
take no part therein. The decision of the
majority of the examiners acting as a
board of appeal shall be final if ap-
proved by the chief of the district
police.

An additional section of the amended
rules provides that a license in force
on Jan. 1, 1912. may be exchanged for
a license of the same class under the
new rules upon application to the boiler-
inspection department of the district
police.

Notes on Grouting Bedplates

While it is infrequent that an engine
has to be raised and rebedded, such a
course is sometimes necessary and has
several times occurred in the writer's ex-
perience. In these instances the trouble
was easily attributable to ignorance or
carelessness in the original setting.

There are several materials available
for engine-bed joints, including portland
cement, iron borings, sulphur and lead.
Of these the last is now but little used
and the iron borings or rust joint so
much used in former years have been
almost entirely superseded by cement,
which by reason of its adaptability to
nearly all cases, its durability, strength
and cheapness is conceded by practical
men to be the best for the purpose.

Cement

Cement needs great care in its applica-
tion and may be Introduced under an
engine bedplate that is from '/i to 6
inches up from the foundation. The
proportion should be one part of cement
to one of good sharp sand, and where the
top of the foundation is uneven (which
is often the case where "cobblestone" or
gravel concrete Is used In construction i
and the joint is thin, the mixture should
be introduced in the form of grout mixed
to the consistency of cream.

The foundation should be thoroughly
wetted, and dams of sand, clay or board,
laid back from the bedplate from 2 to 4
inches, should be built all around the
bedplate, rising above the latter about 2
Inches. The grout may now be poured
In, and at this point in the process great
care Is necessary In order to avoid air
and water pockets. The most efficient
way to avoid these and to Insure an
even flow of grout Is by means of agi-
tators made of ordinary band or tie iron,
which should be inserted Into the joint
while pouring the grout and kept moving
alternately in and out in the manner of
a plunger. The flow of grout is very
sluggish and If is well to remember the
tendency of Its heavier ingredients to
stop flowing and settle while the water
continues on its way. giving the impres-
sion that the joint is full of cement when
it is perhaps half full of water. By

By F. C. Holly

General directiotts

jor

grouting

bedplates and

pre-

cautions

to be obsened.

Mate}

ials used and a

dis-

cussion

of their adapta

bili-

lies.

agitating in tlie manner described, es-
pecially under the ribs, water is sucked
out and the mixture keeps flowing, while
the water rises to the top, some of It
running off over the dam, and uniformity
results.

Any attempt to run a grout joint be-
tween two flat horizontal surfaces with-
out making provision to run off the en-
trapped air and water from under the
ribs will result in trapping air and water
under the ribs, and when the surplus
material is cut away "skips" of various
thickness will appear between the settled
grout and the bedplate where the joint
has failed to fill.

On the other hand, where a vertical
filler is desired, such as anchor-bolt holes,
it is necessary only to pour in the grout,
which in all cases should be continually
well stirred. The body of the mixture
will find the bottom and the surplus water
will rise and flow away when the hole Is
full.

On the girdcr-framc type of bedplate,
where the space between the bedplate
and the foundation is wide enough, (he
cement may be tamped into the joint;
this method has the advantages of neat-
ness and quick setting. The proportions
should be the same but the mixture
should he moistened only enough so that
a test quantity will barely hold together
when rolled in the hands info a hall. It
«hould then be shoved into the joint in
'^mall quantifies and rammed hard into
place. When applied in this way, the ce-
ment will set quite hard in from 10 to
Ifl hours.

The writer considers 12 to 14 hours
long enough for the cement to set before

(removing the dams from a grouted joint,
when it will usually be found plastic and
can readily be cut and smoothed by a
trowel. When dry It should be painted
to keep out the oil.

Rust Joint

The rust joint should be prepared by
mixing a bucketful of iron borings with
a half bucket of water to which has been
added a handful of salt and as much
sal ammoniac or sulphur. Guards made
from flat iron bars passing all the way
through the bedplate should be placed
alongside at the edge of a rib to be
packed and fastened to prevent the joint
squeezing out In the process of packing.
The ribs should be filled half way from
each end.

In packing a rust joint only a small
amount of material should be inserted
at a time. This should be rammed thor-
oughly In place with a rammer made of
flat iron 2 inches wide and as thick as
will smoothly work in the joint. When
properly rammed the joint will give forth
a meiallic sound similar to that caused
by striking the bedplate itself with the
hammer.

Sulphur

Sulphur does not adhere as readily
to the iron face of the bedplate and
the stone or concrete surface of the
foundation as docs either cement or the
rust joint, but it has the advantage over
all other materials in its capacity for
flowing into very thin crevices and is one
of the very few materials subject to prac-
tically no shrinkage in cooling.

Under horizontal bedplates, if the least
movement occurs, sulphur Is likely to
shatter and work out in small pieces,
especially if oil is present. Sulphur rots
and softens under the effects of oil and
should never he used as a joint under a
steam cylinder. In melting sulphur for
use in a joint a slow fire should be had
and the kettle removed from the fire if
the materia! should appear thick or
"ropy" in the bottom, which is a sign
that it is getting too hot. Properlv melted
sulphur pours like wafer and is by far
the most flexible and easily handled of
all the materials used for the purpose.

948

POWER

December 26, 1911

Tom Hunter, Hoisting Engineer

By Warren O. Rogers

Tlianksgiving Eve of 1911 found me
stranded in a large mining town of west-
ern Pennsylvania. The day had been
cold and ancomfortable and toward dusk
the leaden sky became overcast and a
fine, sifting snow began to scud around
the corners and down the street. The
wind soon increased to a gale and by
9 o'clock the air was filled with a
driving snow.

From time to time muffled pedestrians
passed, and one, a miner, with dirty face,
ill-fitting overcoat and greasy cap, from
which hung a miners' lamp, shuffled past,
doubtless on his way to his humble home
after a day's work, performed hundreds
of feet below the surface of the earth.

As he passed from view, I fell to
musing as to why fate should be so
kind to some and so regardless of the
welfare of others, especially on a night
such as this promised to be. An evening
paper lay open upon my knee and, glanc-
ing at a headline, I read, "Lapse of Mind
with Fatal Results."

This title had also attracted the at-
jentior of a stranger, who, like myself,
was seateji by the window, and who
later introduced himself as Thomas
Hunter. Turning to me, he said, in a
somewhat apologetic manner: "The
human mind is a wonderful piece of
mechanism, but at times most fickle. It
will serve a man faithfully for years;
it can be so trained that one will auto-
matically perform certain functions with-
out thought or effort, and then it will
suddenly play him false with such disas-
trous results as to cause vain regrets
for a life time."

Something in the stranger's voice led
me to surmise that there was a story
back of his remarks worth hearing, and
as he accepted a proffered cigar, I said,
"You speak as one having experienced
something of such a nature." As I spoke
I saw that his hair was snowy white, al-
though he was a comparatively young
man.

"I have, he answered, and, continuing,
said: "About twenty years ago I got a
chance to fire a couple of steam boilers
at a small colliery which eventually led
to my becoming a hoisting engineer at
the same mine. I have always been
engaged in mine work.

"Things are different now to what
they were in those days. Then the en-
gines were crude in design and difficult
to operate. About the first engine I had
charge of worked after the plan of the
old beam marine engine; that is, the
engine was started by means of a start-
ing bar, which operated the double-ec-
centric valve-gear. The valve-gear was
hooked up after the engine got on a
little headway. Working the valve levers
and handling the throttle valve, and using

The author meets an ex-
hoisting engineer in the
hotel lobby. He tells some
interesting things regarding
hoisting engines.

The types of hoists are
explained and the advant-
ages of each are pointed out.

both feet and hands in performing these
operations, kept a man on the jump. In
the old days the indirect hoist was used;
for that matter, many are still being
operated."

crankshaft of the engine. The two
drums are either both keyed to the shaft
or one is arranged with a clutch so that
the drum can be revolved on the engine
shaft while the engine is stopped."

"Of course, there is an object for
that," I said.

"Yes; you see the same engine may
hoist from two or more levels in the
mine. When the engineer is hoisting
from a 200-ft. level, the cages naturally
travel the same distance, and when one
cage is at the top of the hoist the other
cage is at the 200-ft. level."

"Yes, that is evident," I replied.

"Then when coal is to be hoisted from
the lower level when one cage is at the
top of the shaft, the other, which would
be at the 200-ft. level, would have to
be lowered to the bottom of the shaft.
Then"

"I see," I interrupted. "The drum is

Tin; Ai.; Was Filled w lih a Dkivinc Snow and Occasionally an Ill-clad
Miner Shuffled Past

"Are there more than two kinds of
hoisting engines?" I inquired.

"There are what are known as the
direct, the indirect and the Corliss valve-
gear hoist, which is something new and
which permits of reversing the engine as
readily as with the piston and slide-
valve types of engine. The Corliss gear
has lately come into use, as has also the
electric hoist, in which the winding drum
is operated by means of a motor."

"What is this direct hoist of which you
speak?" I asked.

"The term 'direct hoist' means that
the winding drums are mounted on the

then thrown out of mesh with the clutch
and the cage at the 200-ft. level is low-
ered to the bottom of the shaft."

"That's it." replied my friend, as he
struck a match and relit his cigar. "Now,
when the drum has been thrown in gear
again, the cages operate as they did
when hoisting from the 200-ft. level."

"How are the clutches arranged on
such drums?" I inquired.

"There are different methods; on some
drums the spiders are made with a four-
fingered clutch. On the shaft is a key
and the movable member of the clutch
slides on the shaft and key. This mem-

December 2b, 1911

POWER

949

ber is made with the same number of
fingers as are on the spider, and when
the two are engaged the drum revolves
with the shaft.

"Another kind of clutch consists of a
gearwheel keyed to the engine shaft and
it meshes with a circular gear rack which
is secured to the rim of the drum. An-
other type has the gear rack made in
segments which are secured to the rim
of the drum. The gears are thrown in
and out of mesh by a combination of
levers and gearing."

"How about the indirect drive?"

"Oh, yes," replied Hunter, "we rather
sidestepped that subject. The indirect
drive consists of a pair of engine cylin-
ders which are connected to the same
crankshaft, on which is mounted a spur
gear. This gear meshes with a large
gear which is keyed to the shaft on which
the winding drums are mounted. The
drum arrangement is practically the same
as with the direct hoist. The engines of
the indirect hoist must run fast in order
to obtain the desired rope speed, where-
as the direct-hoist engines run slower
and make practically no noise."

"The gearing of the indirect hoist must
be noisy," I suggested.

"Some are and some are not. It all
depends on how they are kept up. The
best of them make a little noise and
most of them make more noise than is
agreeable, but it is not so noticeable
when the gear is meshed properly and
the drums are tight; but once let the
gear teeth wear and the bearings in the
engine and drum boxes get loose, then
a boiler shop sinks into insignificance,
so far as noise goes. There are a lot
of such engines running every day."

"It must be trying to the engineer."

"It is," was the reply. "I maintain
that the engine room should be kept as
quite as it is possible to have it. Then
there is nothing to distract the attention
of the engineer from his work. The
direct-motion hoists are practically noise-
less and the engineers like them."

"From that, I take it that the geared
or indirect-motion hoist is being dis-
placed by the direct-motion hoist."

"Well, each has its field. The geared
hoist is adapted for a hoisting speed of
800 ft. or less per minute. First-mo-
tion engines, however, are used where
the hoisting speed ranges from 800 to
4000 ft. per minute."

"Then there is a difference in the
amount of coal the two types of engines
will hoist per hour?"

"Well, the same weight hoisted by a
first-motion engine may be handled by
the geared type of hoist, but there will
be a sacrifice in speed; the indirect en-
gine, however, will not be so large as » ill
be required with the direct hoist. For
instance, if will require a direcf-motinn
hoisting engine of from three to f"ur
times the size of a geared engine to

hoist the same load, and the hoisting
speed and the cost will increase in about
the same proportion."

"You spoke of two types of winding
drums; that is, the straight and conical
face. What is the advantage of one
over the other, if any?"

"Suppose I go back a little in the
historj' of coal mining before I answer
that question. Up to about 1840, coal
seams were worked by tunnels and hoist-
ing machinery was unknown. It was not
even necessary, for coal mining in the
hard-coal or anthracite regions had
scarcely begun.

"As the coal supply became exhausted
near the mouth of the tunnel or slope
and the demand for coal increased, it

plain wood lagging was made with a
straight face. Later, the face was made
of iron, having grooves for the hoisting
rope, and this type was followed by the
conical drum which also has a grooved
face. These later drums are made conical
in order to counter-balance the weight
of the rope. For instance, when the
hoist and car are at the top of the shaft,
the cable has been wound on that part
of the drum having the largest diameter
and the pull or leverage will be greater
than if the drum were of a smaller
diameter, but of the same size from end
to end."

"Yes, I see that," I replied, as I
handed my friend another cigar.

"But," continued Hunter, "with the

Geared and Direct-acting HorsTiNC Engines with Flat and Conical
Winding Drums

became necessary to sink shafts as the
expense of getting coal to the surface
increased. These slopes were fitted with
a single track and the hoisting apparatus
consisted of a mule and whim. As the
slopes became deeper, more powerful
apparatus was demanded and the engine
builders designed what is now known as
the geared hoisting engine."

"Of course, these early engines have
become obsolete," said I, moving nearer
to the radiator as an extra-heavy gust
of wind rattled the windows and the
snow beat against them with renewed
fury.

"There are a few running even now.
Many of them were of the hook-link mo-
lion and were equipped with a wood
lagged drum. Some of these engines
were used in shaft work, but engines
with improved valve-gear were soon
designed for that kind of work and, be-
ing easier to handle, became more
popular. As I have already said, the
first-motion hoi-st with a hiEh drum speed
became popular when deep shafts were
worked.

"The earlier type of drums with their

second car at the bottom of the shaft
the pull on a straight drum would be
equal to the weight of the car, cage and
rope, which would more than offset the
weight of the short length of cable, car
and cage when they were at the top of
the hoist.

"But having the drum made conical,
the rope is wound over the smaller diam-
eter of the drum, and, although the
total weight of the cable, car and cage
is the same as in the case of the
straight drum, the leverage exerted by
the cable is less and the weight of the
rope is thus counter-balanced."

"I see," said I. "By that arrangement
the heaviest load to be hoisted is started
at a slow !^ccd which increases as
the lop is reached."

"That's it exactly," was the answer. "It
makes it easier on the rope and engine."

Just then a distant clock tolled mid-
night and wc retired to our rooms, while
underground, dust-hcgrimed miners were
busy blasting out the coal which must be
hoisted to the surface and which made
hoisting machinery and hoisting engi-
neers a necessity.

950

POWER

December 26, 1911

Efficiency of Reciprocating Engines

The recent contribution of Mr. Heilniann
upon the heat efficiency of reciprocating
engines (see Oct. 31 issue of Powur)
prompts me to take the following ex-
ceptions:

It is not correct to refer to Fig. 8
(original article) as indicating a "uni-
flow" cylinder. It shows a combined uni-
tlow and "reverse-flow" cylinder of which
the action is 60 per cent, uniflow and 40
per cent, reverse-flow. Hence, such a
cylinder has 40 per cent, of all the faults
pertaining to the latter. Through over-
lapping of the two diagrams by 40 per
cent, there occurs a thermal "blending"
and a counter-current effect with corre-
sponding losses. It is in the highest de-
gree misleading to compare this cylin-
der, with the best multiple-expansion en-
gines, when in addition to the introduc-
tion in the exhaust area of a choking re-
lease valve and the omission of all heat-
ing, everything has been done to obtain
the worst possible results.

In one of the tables showing the re-
sults of tests with a boiler pressure of
176 pounds and an initial temperature of
523 degrees Fahrenheit, there is given
a steam consumption per indicated horse-
power-hour of 12.7 pounds. The Badenia
Machine Works, of Weinheim, reported a
consumption of 9.88 pounds per indi-
cated horsepower-hour in an engine of
the same size with a similar boiler
pressure, and a temperature of 600 de-
grees Fahrenheit. (See Zeitschrifi for
1911, page 504.)

It is an error to say that the duty, the
number of cylinders and the valve con-
struction have almost wholly lost their
significance for heat utilization in the
superheated-steam engine of today. As
shown by the curves of cylindei^efficiency*
(GiUegrad) in Fig. 5 (original article)
the Kerchove engine is superior to the
Wolf engine and the uniflow is superior
to both the Kerchove and the Wolf.

Disregarding true uniflow design, the
Kerchove cylinder should be the best
and the Wolf cylinder the worst, with
those of Sulzer and Gorlitz occupying
intermediate positions. It is therefore
not right, for comparison, to advance
the Wolf engine as one of the best.
Separated from the boiler, it must be
designated as the worst, because it has
the largest clearances and the largest
detrimental surfaces of all comparable
engines and in addition a combined inlet
and outlet passage.

The means for combating heat ex-
change are: First, jacketing; second,
multiple expansion, and, third, superheat-
ing. Of those corrective means the Wolf
engine makes the fullest use. Jacket

1)1 an article under the
above caption, li'hich ap-
peared in /nil in Die Zeit-
schrift and was abstracted
in the Oct. 31 issne of
PowEK, K. Hcilmann drew
some comparisons between
the Wolf locomobile and the
Stumpf uniflow engine.

To this Professor Stumpf
replies in the folloieing with
sliarp criticism, depreciat-
ing the Wolf locomobile, and
Mr. Heilmann defends his
former attitude.

*ff!leam consumption in no4oss engiTie tpilh iu-\

\ complete exmniion )

f>leam consxnnplion oj the actual engine

heating is replaced by the more intense
flue-gas heating; the highest possible
superheating is used, and in addition
multiple expansion. Furthermore, there
is utilized in the most advantageous way
the benefit resulting from the conserva-
tion of heat incident naturally to the
union of the boiler and the en-
gine. In this connection Mr. Heil-
mann says: "The use of the highest
possible degree of superheating, from the
standpoint of practical operation, seems
advantageous with the compound en-
gine." He should have added to his,
"particularly with the Wolf compound
engine." Sever the connection with the
boiler, place the Wolf engine and the
compound engine on foundations, and
the dark sides of the former will be re-
vealed at a glance.

It is an error to allege that superheat-
ing is economical in the case of a uni-
flow cylinder. To decide that question,
nothing short of carefully conducted tests
of engines absolutely fault-free in de-
sign and manufacture can be of value.
.^n engine representing these conditions
was the well known 300-horsepower Sul-
zer uniflow engine. This was provided
with a cylinder jacket, but Mr. Heil-
mann's article gives a summary of re-
sults from such uniflow engines as were
not so provided. Although he provided
the compared compound "locomobile"
with the extreme protection of flue-gas
jacketing, he brings forward "uniflow"
results where cylinder jackets were want-
ing and w here there was a corresponding-
ly greater steam consumption.

The results from the 300-horsepower
Sulzer engine are evidently very uncom-
fortable for Mr. Heilmann and he seeks
to get rid of them. During the numerous
tests made at Winterthur, measurements
of the condensate were taken, a method
which, with reference to accuracy and

reliability, excels that of measuring the
feed water. In those tests there were
charged against the engine the entrained
water always carried over by saturated
and often by superheated steam, and the
water of condensation from the cylinder
jackets and the head jackets; these lat-
ter tw^o notwithstanding Mr. Heilmann's
assertion to the contrary. The feed-water
method is uncertain in the matter of
reading the boiler-water levels. Different
conditions of operation at the beginning
and ending of the test also result in ap-
preciable variations, and a skilful ex-
perimenter can give favorable or un-
favorable results. In addition to the
foregoing there are the unavoidable leak-
ages of the stuffing boxes, valves, flanges
and piping.

The firm of Burmeister & Wain, of
Copenhagen, attained the results shown
in Table 1 with an engine of 17.5 inches
cylinder diameter and a stroke of 23.5
inches, running at 180 revolutions per
minute.

This engine was without cylinder jack-
eting. The slight difference in compari-
son w'ith the Sulzer engine results is
easily accounted for by the different en-
gine sizes and by lack of insulation due
to the absence of cylinder jacketing.
This is shown especially with saturated
steam. In this engine, as with the Sul-
zer engine, the valves were absolutely
tight. The steam consumption was de-
termined by measuring the feed water.
The poor mechanical efficiency is ac-
counted for by the insecure mounting at
the works for testing purposes.

A roll-driving uniflow engine built by
Ehrhardt & Sehmer, having 24.5 inches
cylinder diameter and 39 inches stroke,
with a steam pressure of 140 pounds
at a temperature of 376 degrees Fahren-
heit, gave a steam consumption of 12.25
pounds per indicated horsepower-hour;
a result which, considering the lack of
cylinder jacketing, is again very close
to the Sulzer results. Here too the feed
water was measured.

A uniflow steam engine built by John
Musgrave & Sons, Ltd., Bolton, England,
gave a steam consumption of 10.85
pounds per indicated horsepower-hour
with an initial pressure of 120 pounds,
and a steam temperature of 490 degrees
Fahrenheit. The steam consumption was
determined by feed-water measurement,
and again, bearing in mind the absence
of cylinder jacketing, the results ap-
proach those of the Sulzer test. The
same firm built another uniflow engine
which, with an initial pressure of 162
pounds, a steam temperature of 518 de-
grees Fahrenheit, and a good vacuum,
and without cylinder jacketing, showed
a steam consumption per indicated horse-
power-hour of 9.9 pounds.

December 26, 1911

POWER

051

It is an error to state that the uniflow
engine has an unfavorable mechanical
efficiency and that the high compression
unfavorably influences the latter. High
compression eliminates the pressure-di-
rection change from the stroke reversal,
makes the engine run smoothly, and
through these results improves the me-
chanical efficiency.

However, as long as the gross load
and the net load are the same, there
cannot be any argument concerning
the unfavorable influence of high com-
pression on mechanical efficiency. In
accord with this are the published

pressure of 176 pounds per square inch
and a temperature of 572 degrees Fah-
renheit, as follows:

With mean effective pressures of II,
22, 33, 44 and 55 pounds per square inch
and respective mechanical efficiencies of
0.88, 0.885, 0.92, 0.94 and, again, 0.94
corresponding steam consumptions in
pounds per indicated horsepower-hour
of 9.35, 9.35, 9.(58, 10.12 and 11 per
indicated horsepower-hour. These values
agree with those shown by Fig. 1.

Noteworthy is the steam consumption
with the mean effective pressure be-
tween 11 and 22 pounds, and for which

T.\BI,E 1. D.\T.\ FROM BUR.\IK1:ST1;K & WAIN TICST

^

^ '

s

ti

"s S

1

35?

^

'^a

^X

64.50

97.7

114. S

.S6.46

12S.7

147.5

108.66

161.4

l.'43.6

131.24

in.-..o

21t).7

109.00

162.0

1S4.0

Or-'

£4

140.5
140.1
139.7
139.1
13S.4

-^

ai:.;

r3 —

^N_^

- ?

— r

>S

666

2S.2

669

28.1

667

28.0

667

27.8

ilry sat.

27.9

59.

16.37
16.10
16.19
16.39

9.06
9.28
9..i4
9.68
13.64

tests at the Alsatian Machine Works
Company, showing a mechanical effi-
ciency of 92 per cent., a result which
Mr. Heilmann conveniently overlooks.
Similar, and in part better, results have
since been given by many other uniflow
engines. At present there is no uniflow
engine in which the gross load exceeds
the net load. Such indeed, however, is
the case with many expansion engines.
It is thus entirely wrong for Mr. Heil-
mann to consider the quotient:

Ciim />r<' i ( ion load

Indicalid lo,ul -\- comt^resiion had
as the coefficient of mechanical efficiency.
Compression can serve to very much
improve the mechanical efficiency by bal-
ancing, or evening up. the forces and by
lessening the blow effect or pounding.
The whole basis of the obser\ations by
Mr. Heilmann and the resultant conclu-.
sions are wrong and in direct contradic-
tion of results. But particularly faulty
is the conclusion that on account of the
alleged poor mechanical efficiency, the
economically favorable cutoff represents
an average pressure of 44 pounds. With
ample jacketing the favorable average
pressure in the case of the 30fl-horse-
power Sulzer uniflow engine was about
32.2 pounds, referred to the elTective
duty (see Fig. IL

If is thus more than faulty when Mr.
Heilmann, through his wholly wrong
basic comparison, declares ar: efficiency
of from 0.82 to 0.83 for an average pres-
sure of 23.5 pounds. For example. Sul-
zer Brothers guarantee a steam con-
sumption for a uniflow engine with a
cylinder diameter of 33.5 inches and a
• troke of 39.4 inches, with steam at a

Mr. Heilmann introduces a pressure of
44 pounds.

The greatest friction losses are due to
the piston and the stuffing-boxes, to the
main bearings and in decreasing value
to the other bearings. As the normal
uniflow engine has but one piston and
one stuffing-box as compared with two
pistons and two stuffing-boxes for the

i n.0

KX) ^

cL

f -

.1

1 "■'

^

60 5-

c

/

s

'

>^n

..^(

^^

1

S

h22r!i3^

r -N

-U-X^

«,'^

i"

^■-^

J **

"1

'

1 n

1

0

14.E ZM 4?.6 96A 71.0

Mcon E*f«£tiv« fVessorr per Square lnch-(b.
' r<na.

Fic. 1. Result with Si'lzer Enoinf

Wolf engine, and as in addition the main
bearings, owing to the lighter flywheel,
are less heavily loaded, there cannot be
any argument in favor of the superiority
of the tandem engine with reference to
mechanical efficiency. In order to figure
nut the most unfavorable piston pres-
sures possible for the uniflow engine, in
comparison with the tandem-compound
engine. Mr. Heilmann takes a ratio of
1:4, something unknown in stationary
steam engines.

Mr. Heilmann holds thai the high com-
pression of the uniflow engine is a ther-

mal fault, though such compression, with
a good vacuum and a corresponding
clearance, can be varied almost at will.
He, however, considers himself justified
in always compressing up to initial pres-
sure in his high-pressure cylinder, some-
thing which never happens in the uniflow
cylinder. Mr. Heilmann thus compresses
higher in his reverse-flow cylinder than
is done in uniflow engines, at the same
time declaring that high compression in
the latter is nonsensical and useless.

It is an error when Mr. Heilmann as-
serts that the uniflow engine is limited
to a small total expansion. A- glance at
Fig. I shows that with good construction
almost the same average pressure can be
used as in the compound engine. The
losses through throttling in the high-
pressure discharge passages, the receiver,
the low-pressure inlet and outlet, as
well as the heat losses of the high-pres-
sure cylinders and the receivers, disap-
pear with the uniflow engine. As a re-
sult of these losses the compound dia-
gram, running condensing, must be less
complete than the uniflow diagram. Mr.
Heilmann consoles himself with these
losses being made good in the low-pres-
sure cylinder. The plotting of an en-
tropy diagram, however, shows that only
one-third of such losses are recovered.
The losses by radiation are appreciably
larger in the compound engine than in
the uniflow engine.

The inves;igation of the Wolf com-
pound locomobile with saturated steam
showed a cylinder efficiency of 73 per
cent., and with superheated steam at 617
degrees Fahrenheit, a cylinder efficiency
of 86 per cent.; both referred to a ter-
minal pressure of 33 pounds absolute.
The Sulzer uniflow engine with saturated
steam gives a cylinder efficiency of 88
per cent., and with superheated steam at
617 degrees Fahrenheit a cylinder effi-
ciency of 89 per cent., both values again
referred to a terminal pressure of 33
pounds absolute. The cylinder efficiency
includes the losses due to clearance, the
thermal losses, the throttling losses and
the losses through leakage.

In Fig. 2 are plotted the cylinder effi-
ciencies {(jiitcgrad) of the 300-horsc-
power Sulzer uniflow engine as dependent
upon the cutofT with saturated steam and
with steam of 617 degrees Fahrenheit;
in both cases steam jacketing being em-
ployed. In these efficiencies arc con-
sidered the losses due to throttling, the
thermal losses and those incident to
leakage. These cur\'cs sh.jw the small
cfTcct of superheating.

In Fig. 3 are shown ideal slcam-con-
siimplion values of a .lOO- horsepower
uniflow engine, calculated with reference
to the influcncr of clearance and using
the cylinder efficiencies plotted in Fig. 2.
but recnlctilatcd first for the «lcam pres-
sures and temperatures of the Wolf tan-
dem locomobile and second for the steam

952

POWER

December 26, 1911

pressures and temperatures of the Ker-
chove engine.

Particularly noticeable is the inferior-
ity of the Wolf engine with saturated
steam, whereas a striking superiority
shown on the side of the unifiow engine
is its minimum steam consumption un-
der all practical steam temperatures. If
the unifiow curves were recalculated for
steam consumption, and if there were

out SO per cent, of the stroke, such sur-
faces in the ordinary steam engine be-
ing in constant contact with the live
steam and, for 60 per cent, of the stroke,
most concerned in heat transfer. Based
on the observation in question as given
in my original article and as shown by
the diagram of Fig. 6 (page 661, Oct.
31 issue), it appears that the injurious
effect of the walls of the exhaust pass-

0 0 +:

90 ^

£8.4

,

c,feam

! 1 !

f

^.Si^^S^i^-^

fed Sfeam

bl / l^e^rees Fahrenhei

'

"''I'

rs^py

- +e^

rri,^'

.^

^

^

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t

t1.e-

^cc^

617 r"'

i^

m.

rv«'

5^"

^

^<

r

ICl'

4 6 8 10 12 14 16

Cut-off , Per Cent

Fig. 2. Effect of Cutoff Upon Cylinder Efficiency

unifiow cylinder of about 10 per cent.
The assertion that the cylinder shown.
Fig. 8, is afflicted with 40 per cent, of
all the faults of the reverse-flow cylinder
indicates a wholly superficial and un-
scientific manner of obser\ation, misled
by the term "unifiow" engine. The "uni-
fiow" direction within the cylinder is
unimportant as the flow velocity of the
steam over the piston surfaces is low,
and also because, leaving out the dif-
ferent velocities, the proportion of loss
due to the cylinder is very small (K, +

^ X

J" I3.E
0

\Wotf Tandem Locomobi/e
^ Steam Pressure 2351b. Abs.

' Uniflow''EngJne

Steam PreUure Z35lb. Abs

^Kerchove Tandem Engine
^^^Steam Pressure ISO lb. Abs
^Un'rflow ^Engine
Steam Pressure 1501b. Abs.

powE, 392 572 75?.

5team Temperature, Deqrees Fahrenheit

Fig. 3. Comparative Steam Consump-
tion of Wolf Locomobile, Kerchove
and Wolf Uniflow Engines

taken into consideration the use of the ages of the cylinder shown in that fig-
jacket condensate as feed water and ure or in Fig. 8 (page 661, Oct. 31 is-
the lesser oil consumption it would sue of Power) is very small.
be found that the consumption curve Exhausting free, the cylinder repre-
would closely approach a horizontal sented by Fig. 8 is superior to that of
line- Fig. 7 (same page) in that, by the lat-

TABLE 2. (M)MPARATIVE TESTS WITH FEED WATER .MEASUREMENT A.\D
CONDENSATE .AIEASUREMENT

Cylinder dimensions,
inclies

Steam pressure, pounds . .

Steam temperature at tlie

throttle, degrees Fahr..

Revolutions per minute.

Indicated liorsepower. . . .

Hourly steam consump-
tion per effective horse-
power-liour with:

Feed-water measurement,
pounds

Ooiidcnsate.measurement ,
potmds

Increased consumption
with feed-water meas-
urement in per cent . . .

Jacket condensation in
per cent

Hori-
zontal

Com-
pound

•358

(satur-
ated)
80.8

15.48
14.60

Hori-
zontal
Tan-
dem
En-
gine

13 and

10.45
9 79

Horizontal

Compound

Engine

24 and 41x4:i

Unifiow Engine

10. SR
10.20

135

135

509

358.5

(satur-

ated)

1,50

1.50

alia

bout

9 . 50
8,8

10.60
15. S

357

(satur-
ated)
150

AIr. Heilmann's Reply

Regarding the objections raised by
Professor Stump f, I would reply as fol-
lows:

As proved by me in detail, the value
of the unifiow design rests primarily on
the surfaces of the exhaust passages be-
ing excluded from heat transfer through-

ter, the disadvantages of high compres-
sion with atmospheric exhaust are par-
ticularly noticeable. Comparative tests
made by Professor Grassmann of two
cylinders, which differed from the sin-
gle cylinder only in the use by the lat-
ter of the unifiow and its consequent high
coinpression ratio, showed with free ex-
haust an increased consumption by the

V„ in the diagram of Fig. 6 of my arti-
cle).

The heat utilizations of the investi-
gated compound engine, the unifiow en-
gine with shallow piston and without
jacketed heads, and the unifiow engine
of Professor Stumpf's design were con-
sidered by me Separately. Professor
Stump f seeks to present the subject as
though I had merely compared the re-
sults from the unifiow cylinder of the
type shown in Fig. 8 with the results
from the best compound engine, which
is entirely incorrect.

With reference to the cylinder shown
in Fig. 8 I stated that it was constructed
for high superheat and for that reason
was wholly unprovided with any jacket
heating, and that the tests with saturated
steam and moderate superheating were
made only in the interest of science.

When Professor Stumpf says further
that in the cylinder, as shown by Fig. 8,
"through the introduction in the exhaust
area of a choking release valve and the
omission of all heating, everything has
been done to obtain the worst possible
results," it is sufficiently evident that his
intent is to depreciate the purpose and
value of the tests. I would say that the
loss through throttling effect in the ex-
haust passage and in the operating valve
for this cylinder has so far not been 1
per cent.

The advantages of the locomobile de-
sign are expressed in fuel consumption
much more than in steam consumption.
Professor Josse says: "In the iocomo-

December 26, 191 1

POWER

953

bile the piping losses and the heat losses
through condensation disappear; hence
the superiority of the locomobile over
stationary installations as regards econ-
omy." An advantage of the locomobile
is the possibility of intermediate super-
heating by means of the waste gases at
almost no cost. For that reason I brought
under consideration only tests made
without intermediate superheating for
comparison with stationary engines.

Thermally considered there is no con-
nection between the boiler and the en-
gine. With steam at a pressure of 220
pounds and a temperature between 644
and 662 degrees Fahrenheit, the steam
consumption, as an average of several
tests and with different loads, amounted
to 8.25 pounds per indicated horsepower-
hour and 8.8 pounds per effective
horsepower-hour. The fuel consumption
amounted on the average to 0.97 pound
with feed-water heating by the waste
gases.

In the use of highly superheated steam
and compounding it has been proved that
the simple slide-valve engine, even with
less favorable proportions in the matter
of detrimental surfaces, approaches in
Its results the inost complicated poppet-
valve engine.

The value of the so-called uniflow de-
sign I did not question; quite the re-
verse, I proved it in detail. I did dispute
that with the uniflow design compound-
ing and superheating became superfluous.
I agree throughout with Mr. Stumpf that
for the deciding of this question only
carefully carried out tests can be of
value. I would add that the details of
tests must be included insofar as they
are necessary for the determination of alf
relationships. The tests on which Pro-
fessor Stumpf bases his deductions do
not represent the contention at issue. It
is not right if tests with the condensate-
measuring method are compared, without
further investigation, with the feed-water-
measuring method. It is not with the
latter method but by the former that
a skilful investigator can at will deter-
mine very favorable results. This would
apply particularly with the jacketed re-
ciprocating steam engine; much less so
with the steam turbine. Table 2 shows
the differences as deJermined between
feed-water measuring and condensate-
measuring methods with reciprocating en-
gines. It appears therefrom that the
differences are larger as the load is
smaller. The much greater difference
determined for the uniflow engine with
saturated steam cannot be explained by
greater leakage but only by the jacket
condensation, particularly noticeable with
saturated steam, flowing back through
the piping and remaining unaccounted
for.

In the engine tests by Burmeistcr &
Wain (compare with Table 3), the aver-
age mean effective pressure was some-
where between 3.3 and 6.6 pounds.

Only during the last three tests was there
an approximation toward normal loading.
The mechanical efficiency was about 89
per cent. The consumption figures at
normal loading correspond closely with
my curve of comparison for the uniflow
engine. The increased consumption with
saturated steam as compared with steam
at 662 degrees Fahrenheit amounts to
about 40 per cent., a proof that with this
engine superheating is in no way super-
fluous. Referring to the uniflow engine
of Ehrhardt & Sehmer of 24.5 Inches
cylinder diameter and 39 inches stroke,
there are wanting both the load and the
mean effective pressure.

In the comparison of different engines
for economy, tests made under conditions
of their nominal loading should be
chosen. Comparison on an^' other basis
I declare to be wrong.

A striking proof of the correctness of
my assertion that for economy compari-
son tests made under nominal load con-
ditions should be used, and that a mean
effective pressure of about 44 pounds Is
to be considered as suitable for the uni-
flow engine Is furnished by the calcula-

Is the low mechanical efficiency of the
uniflow engine with free exhaust. The
assertion that I conveniently overlooked
the 92.5 per cent, efficiency of the
Alsation Machine Works' engine Is in-
correct; but I did overlook that this effi-
ciency is understood as excluding the
need for condensing and that when in-
cluding it the efficiency drops to 89 per
cent.

Lorenz, In Zcitschrift for 1894, page
1267, stated and proved that for a given
Indicated load of an engine the mechani-
cal efficiency becomes smaller the greater
the compression. In other words, the me-
chanical efficiency grows smaller the
greater the ratio:

(0

:y, + Av

chosen by me to represent the results
of the tests, and In which

Nr = Compression load or work ab-
sorbed by compression;
A^i' = Indicated load;
A^i = Effective load.
The noticeable fact that the friction
load with increasing ratio (1) rapidly

STF,.\M AND Hi:.\T CONSrMPTKi.N.S OF TIIK .sfLZF-U VNIFLOW ENGINE
PER EFFECTIVE IIOR.SEPO^\'EH-HOrR, C.MX'fLATED FROM
THE ST.'VTEMENTS OF PROFESSOR STUMPF

Mean effective pressures, pounds per

square inch

11

22

3.t

a

5,5

.<Iram consumption piT effective
liorsepower-hour, pounds

Ileal consumption per effective
horsepower-hour, B.t.u

12.1
I.';,872

10. .%6
1.-J..S48

10 -,6
1.1. SIS

10.78
14.166

11 66
l.i.316

Il'at con.sumplion per effective
horsepower-liou r of I he Wolf com-
iiounrl encine le.sted by Professor

in.SR4

tions for steam and heat consumptions
for the effective horsepower of the Sul-
zer engine, based on the statements of
Professor Stumpf (see Table 3l. The
steam consumption per indicated horse-
power-hour with a mean effective pres-
sure of 1.7 pounds Is, as is evident, en-
tirely worthless for determination. A
comparison with the heat consumption
of the Wolf compound engine tested by
Professor Doerfel shows the high value
of compounding as favoring the use of
high steam pressures and temperatures.

Mechanical efficiency Is primarily de-
pendent upon the proportions of the driv-
ing mechanism, and under certain cir-
cumstances compression is of high sig-
nificance.

As the uniflow engine, on account of
the greater stresses in Its driving mech-
anism, requires a heavier shaft, and as
the piston friction is undoubtedly higher,
the lesser mechanical efficiency of the
uniflow engine is sufflcicntly proved, be-
ing, from the foregoing tests, not over
90 to 01 per cent. As far as it was pos-
pible, I calculated the mechanical effi-
ciencies shown by the tests included in
Professor StumpTs book "The Uniflow
Steam Engine." Particularly noteworthy

augments while the indicated load falls
off, leaves no doubt as to the significant
influence of compression.

The remark of Mr. Stumpf, "In order
to figure out the most unfavorable piston
pressures possible for the uniflow engine,
in comparison with the tandem-compound
engine. Mr. Hcilmann takes a ratio of
I:^. something unknown in stationary
steam engines." indicates another attempt
to depreciate the value of my demonstra-
tions. The cylinder ratio of 1 :4 Is the
rule for the Wolf locomobile with super-
heat, and hence there was no arbitrary
assumption.

High compression In the high-pressure
cylinder of a compound engine Is neither
thermally nor mechanically disadvantage-
ous to the extent that it is In the uni-
flow engine because the compression path
is vcr>' short and because the volume at
cutoff In the high-pressure cylinder Is
relatively large. In spile of high com-
pression In its high-pressure cvlinder and
its further infcrinrilv. as alleged hv Mr.
Stumpf, the tola! efficiency of the Wolf
encinc even with entirely normal con-
struction with a simple piston valve is
far belter than that of the uniflow en-
gine.

POWER

December 26, 1911

An Analysis of Some Recent
Gas Engine Failures

By Howard S. Knowlton

Increasing experience with gas en-
gines in power plants operating in
many localities and under widely
varying conditions ' is doing much to
indicate and correct weak spots in
design and service performance. In the
following notes, drawn from an insur-
ance engineer's report, are given the
main facts in connection with a number
of recent gas-engine breakdowns, the
material being gathered in actual power-
plant practice by the technical staff of
a large company underwriting machinery
of this kind against failure.

The first failure occurred with an en-
gine using illuminating gas. The trouble
was due to a makeshift method of pro-
tecting the attendants in the station from
an overhanging flywheel carried on the
crank shaft. The protection was at-
tempted by providing a guard having a
central hole through which one end of
the shaft projected. For some reason,
this guard had sagged sufficiently to
rest upon the shaft, and to prevent con-
tact it had been raised and held up by
a weight at the end of a rope passing
over a block hung from a beam over the
engine. After a while the rope broke and
the weight fell into the crank space,
where it was caught and driven through
the bedplate by the large end of the con-
necting rod. The bedplate was cracked
in three directions from the hole and the
connecting rod was bent.

Another brefkage occurred to an 11x19-
inch gas engine nine years old, running
at 200 revolutions per minute. Atten-
tion was drawn to the defective condition
by a violent blowing through the piston
at each explosion in the cylinder. The
engine was at once stopped, and when
an inpector was called, the piston was
withdrawn, and a hole about 2x'/. inches
was found in the end. On taking out
the connecting rod the hole was found
to have been caused by a setscrew used
to hold the rear brass in the small end
of the rod. This screw had worked loose
and come out; its head had been broken
off and had worn a hole nearly through
the end of the piston, and finally had
been driven through the remaining thick-
ness of metal.

An interesting case of bolt failure oc-
cOrred in a 20x30-inch horizontal gas
engine running at 160 revolutions per
minute and developing an initial pressure

Everything"
worth while in the gas
engine and producer
industry nil! be treated
here in a way that can
he of use to practi-
cal men

on the piston of about 375 pounds per
square inch. The cap at the larger end
of the connecting rod was secured by
two bolts of the dimensions shown in
Fig. 1. Two sets of bolts were kept,
each set being used alternately for per-
iods of 6 months, and then annealed.
When near the end of its third run, the
upper of the two bolts broke close to the
head through a iii-inch hole drilled for
securing a feather key for preventing the
bolt from turning when the nut was be-
ing screwed up. The other bolt was bent,
drawn down to a diameter of 1!j inches,
and broken at a and b. The piston, cyl-
inder, cylinder liner and water connec-
tions to the jacket and piston were broken

overheating of the cylinder and its sub-
sequent fracturing at the end, the second
fracture in eight years. The discharge
from the cylinder jackets should never
have been allowed to rise above 120 de-
grees Fahrenheit, and proper facilities
should have been provided for removing
deposit from the heated surfaces and
narrow passages over and through which
the cooling water circulates. Not a few
gas-engine troubles are due to this neg-
lect of the cooling-water conditions and
service.

Fig. 2 illustrates a crank shaft which
failed between the flywheel and the crank
bearing. The engine was of the hori-
zontal type, nine years old, with a 6>ix
15-inch cylinder; the speed was 200
revolutions per minute. Illuminating gas
was the fuel. The engine had one fly-
wheel weighing about 800 pounds. The
shaft broke in the bearing, the fracture
extending practically into the keyway. It
was estimated that the engine had made
288,000.000 revolutions and about 50,-
000,000 explosion strokes. The engineer-
ing staff of the insurance company fig-
ured that assuming an initial pressure

|mlll|l|)l>||Vjr|i|)|)||;

3iC:^.//'--L- aU ^^^-^pL..^l^. jtlL ._^Jd^- i ^ . -vJ^ISj.

j X/^ >f^ ■i,^ ^-^ i^lS ^■^ ■»;« —>^ »,g ■— — >I^K^

FiG. 1. Fractured Bolt

and the connecting rod bent. The fracture
at a appeared to have started at the
feather key and worked its way gradually
through the bolt, as the final break
covered a very small area, about lxi>,
inch. The cap of the connecting rod w'as
indented by the heads of the bolts, the
upper one penetrating about i'„ inch, and
the lower one h inch. The butt end of
the rod was also scored by the nuts,
indicating that at some time the bolts
on the other pair had been allowed to
work with the nuts slack. It was not as-
certained whether this or too high a tem-
perature in the annealing furnace caused
the failure.

Wear and tear and the working of the
engine under adverse conditions caused
a break in a 20x24-inch engine running
at IfiO revolutions per minute. Gas was
supplied from the city mains. The water
used for cooling the cylinder jacket w-as
insufficient in quantity and heavily im-
pregnated with lime. This led to the

of 300 pounds per square inch on the
piston, the stress on the neck would be
about 21,000 pounds per square inch.
The stresses were calculated on the sup-
position that all pressures and reactions
act through the middle points of the
bearings to which they are applied. It
appeared that the cause of the break
was weakness. In order to reduce the
stress to the lower point of 9000 pounds
per square inch, the diameter of the
shaft would have had to be ZV% inches
instead of 2'j inches. .A most singular
phase of the failure was the fact that
the shaft of another engine over 100
miles away, of the same make, and bear-
ing the next consecutive shop number
broke on the same day and in the corre-
sponding bearing.

Another shaft failure occurred in a I2x
18-inch engine running at 160 revolutions
per minute. The crank shaft was sup-
ported by two bearings and carried two
overhanging flywheels, as indicated in

December 26, 1911

p o v;' E R

955

Fig ■ The shaft broke through the
left-hand neck close to the crank, and
was also found cracked half-way through
the right-hand neck. The stress was low-
in this case, only about 8500 pounds per
square inch, but there were practically
no fillets at the junctions of the necks
wi^h the crank webs. The engine had
made about 288.000,000 revolutions and
carried about 72,000,000 explosion
strokes prior to the accident.

The next case was a horizontal gas
engine, about 18 months old. having an
185I'x24-inch cylinder, running at 160
revolutions per minute on suction pro-
ducer gas. The exhaust pipe, 8 inches

Flywheel SOO lb.

' '^^ F^''^'^'^'^ ■ ;-h

?rk-?|5j<2|j^

responding closely to red heat. If the
rollers carrying the muffler had been laid
on an iron plate, and more space left
between the muffler and the wall, little,
if any, trouble would have been en-
countered.

Defective lubrication caused another
representative failure. The engine was
of the horizontal type, 11x21 inches, run-
ning at 180 revolutions per minute on
illuminating gas. The valve-gear shaft
was driven from the crank shaft by a
pair of wheels and ran alongside the
engine frame. The caps of the bear-
ings for the lay shaft contained oil boxes
closed by lids. The bearing next to the

Another case of interest was that of
an UxlT-inch engine, running at 190
revolutions per minute on illuminating
gas. The cylinder jacket was cast with
the breech end, the liner and engine
frame being in separate castings. The
liner at the rear end abutted against a
faced surface in the breech end and at
the front end against a similar surface
on the end of the frame. When the
flange at the front of the jacket was
tightened against the frame the liner could
expand only by breaking or stretching the
bolts by which the frame and jacket were
held together, by tearing off the jacket
or breaking the latter circumferentially.

Flywheel 1700 lb.

FlyiKheel nOCIb.

^t^X^^"^

7"^

D

l^..,lL^n".L...,.r-L^,^'.A

Fic. 2.

Fig. 3.

in diameter and 'i inch thick, was ver-
tical 14 inches from the bottom of the
breech end and then ran horizontally for
9 feet in a trench to a connection with
a muffler. The latter was of unusual
weight on account of an addition erected
on top of the original box. The latter
rested on two iron rollers ?« inch in
diameter, which in turn rested on the
concrete bottom of the trench. The dis-
tance from the back of the muffler to
the end wall of the trench was 2 inches.
The exhaust pipe cracked circumfer-
entially close to the flange by which it
was attached to the breech end of the
cylinder, and on the side facing the
muffler.

Subsequent examination disclosed that
the concrete under the muffler had
been softened by oil and water and the
rollers had sunk into it. The exhaust
pipe was therefore exposed to the sum
of two stresses, one the frictional resist-
ance of the muffler sliding on the concrete
instead of moving on the rollers, and that
from the bending moment produced from
the settlement of the rollers and muffler.
The first would be of little account unless
something lodged between the muffler
and the end wall of the trench; the sec-
ond, measured in pounds per square
inch, would be three times the weight of
the muffler and discharge pipe leading
from it into the air. except as modified
by the elasticity of the bottom of the
breech end and of the joint between it
and the pipe. This weight was not de-
termined, but it would not have had to
be large in order to cause the fracture.
since the internal surface of the pipe
had been exposed to a temperature cor-

crank shaft was located between the fly-
wheel and the engine frame, and not
easily accessible while the engine was
running. The bearing became hot and
seized through lack of oil, and the brack-
et carrying it, as well as the driving
wheels for the lay shaft, were broken.
It was pointed out in the report of the
engineer of the casualty company that

In this case the bolts were broken ami
the jacket was saved. The accident em-
phasized the fact that proper allowance
for the expansion of a liner for a gas-
engine cylinder is absolutely essential.
A poor arrangement of air intakes was
responsible for no little trouble in an
8'jxI5-inch engine running at 160 revo-
lutions per minute on illuminating gas.

Fic. 4. General Arrangement of PRoni'ctR Pi ant

the lubrication of the lay shaft is a weak
point in many gas engines. The arrange-
ment in this case was particularly bad,
since the attendant could not sec whether
the oil box was full or empty while the
engine was running. Conditions would
have been much Improved by the use of
a glass lubricating gage, although bet-
ter result* would have been obtained
with ring lubrication.

The air for the cylinder charges wB9
drawn through (he interior of the bed-
plate, to which it was admitted by slots
in the side The arrangement was clear-
ly hazardous. It wa« pointed out in the
repnn of the accident that if bv any
means, such as leakage past a slighlly
open gas cock, gas should be forced into
the cylinder during a stoppage of the en-
gine, and if the engine should br <itnppcd

956

POWER

December 26, 1911

with the exhaust valve open, the space
inside the bed would be filled with a
combustible mixture of gas and air which
might easily be ignited in starting. Some-
thing of this character evidently occurred
in the above case. On restarting, an ex-
plosion occurred inside the bedplate. The
latter and a large casting on which it
stood were damaged beyond repair, all
the flywheel arms broken and the rims
detached from them, besides minor in-
juries.

Fig. 4 shows the arrangement of a gas-
engine installation in which a bad explo-
sion occurred in the expansion box out-
side the engine. The plant was of the
suction-producer type, comprising a gen-
erator A, a purge pipe and cock B, a
wet scrubber C and expansion box D;
there were also two fi^-inch unsealed
drains £ and F, an escape pipe G and
testing tap H. The engine was shut
down for the end of the week one even-
ing, the valves in B ind G being left
shut and the drains £ and F open. On
the next day the generator was cleaned
out, and on the second morning, which
was Sunday, the fire was lighted, the
cock B opened and the drain cocks shut.
About 2:30 p.m., an explosion occurred
and the top of the expansion box D was
blown off. The explanation of the acci-
dent given in the report was as follows:

As soon as the drains E and F were
opened, air had access to the expansion
box D, and when the fire was burned
down and the generator cleaned out, to
the scrubber also. Thus explosive mix-
tures, probably of different strengths,
were formed in each, and ignition, fol-
lowed by explosion, occurred as soon
as the fire when rekindled had burned
through sufficiently to send a spark or
flame into the pipe leading to the scrub-
ber. At the time of the explosion the
fire in the generator was probably burn-
ing more fiercely than usual, on account
of a strong wind which was blowing.
If the drains £ and F had been sealed by
water, air could not have entered the
expansion box through them; if the pipe
entering the scrubber from the generator
had been water sealed, air could not have
backed into the scrubber; if there had
been a two-way valve at the junction of
the generator delivery pipe with the purge
pipe, allowing alternative connection be-
tween the generator and the purge pipe
or the generator and the scrubber only,
air could not have entered the scrubber
even if there had been no water seal at
the bottom of the latter.

On the advice of the insurance in-
terests the water seals and the two-way
cock mentioned were installed. In spite
of this a few months later the cover of
the expansion box was blown off again.
The explosion occurred soon after start-
ing the engine, after it had been stand-
ing for four days, the cause in this case
being a bad joint between the expansion
box and its cover, through which air

entered the box and diluted the gas in-
side. Before starting the engine the
two-way valve substituted for the valve
B on the diagram was opened from the
generator to the atmosphere, and the fan
used until the gas appeared at a test
cock (not shown on the diagram) be-
tween the generator and the scrubber.
The two-way valve was then turned to
place the generator in communication
with the scrubber, and the engine was
started with illuminating gas. As soon
as it was in motion the illuminating gas'
was cut off and the valve between the
engine and the expansion box D opened,
admitting to the cylinder the diluted but
explosive gas, which burned slowly and
remained lighted until the gas valve
opened to admit the next charge. This
charge was ignited while the admission
valve was still open, and the flame ran
back into the expansion box, which,
owing to the leaky joint above mentioned.

transversely. The trouble was clearly
due to the expansion of the water in the
jacket at the moment of freezing. The
danger of leaving jackets full of water
and engine rooms unheated has often
been emphasized by accidents of this
character.

The Bogert Auxiliary Heater

It has long been recognized by gas-
engine designers that the temperature of
the exhaust gases is sufficiently high to
be used for the purpose of heating. In
England, a considerable business is done
at the present time with a horizontal type
of tubular boiler through the tubes of
which the exhaust gases pass on their
way to the atmosphere. It is said that this
boiler generates from ZVi to 3 pounds of
steam at 60 pounds pressure per brake
horsepower-hour when the engines are
operating at nearly full load.

Fig. 1. Heater Connected to Engine

was filled with an explosive mixture of
gas and air. If the attendant had opened
the valve G and kept the fan working
until undiluted gas was obtained at the
test cock H the explosion would have
been avoided.

The freezing of water in a jacket
caused a failure in the case of an 8x15-
ineh horizontal engine 14 years old, run
on illuminating gas. The engine was
located in an outbuilding in which a gas
jet was supposed to be lighted during
cold nights, and the cylinder jacket was
provided with a drain through which it
could be emptied. The jacket was found
split longitudinally from end to end after a
Sunday shutdown, and the breech end
was also cracked both longitudinally and

A serious drawback in boilers "fired"
with exhaust gases and made wholly of
steel or wrought iron is that the metal
suffers corrosion when coal containing
sulphur is used, resulting in rapid de-
terioration. To meet this objection, John
L. Bogert, consulting engineer of the
New York Engine Company, some time
ago designed a cast-iron sectional boiler,
which embodies several interesting fea-
tures. Fig. 1 shows a vertical section of
one of these boilers, having 11 sections
or elements. Fig. 2 shows a plan view
of half of one of the elements and a
vertical section of two of them, from
which the method of building up the
heater can be readily gathered.

The shell is of steel plate, but it is lined

December 26, 1911

POWER

957

with ordinary brick, standing on end,
for the purpose of confining the heat
and also preserving the shell from cor-
rosion. The gases pass through the shell

Detail Construction of Ele-
ments

outside of the cast-iron sections and the
water is contained within the sections.
The sections or elements are connected
by threaded pipe nipples and the holes
through the elements are staggered. The

ments, somewhat as in the Ma.xim
silencer for firearms.

The compactness of this apparatus is
illustrated by Fig. 3, which is a view of
a power installation of two suction pro-
ducer-gas engines, of 50 brake horse-
power each, discharging their exhaust
through one Bogert heater. The jacket
water is fed from the jacket of the en-
gine into the top section of the heater,
and passes out through the pipe at the
bottom. In this direction of flow of the
water the hottest water comes in contact
with the hottest gas and the coolest in
contact with the coolest. The two en-
gines here shown constitute the power
plant for the boiler shop of the New
York Engine Company, and they also
drive a two-stage compressor which fur-
nishes compressed air for the whole
plant. The engine cylinders are 15 inches
bore by 21 inches stroke, with crank
shafts coupled to a common shaft carr>'-
ing a flywheel and driving pulley, and
they run at 200 r.p.m. The heater shell
is less than 30 inches in diameter.

The power plant runs usually 10 hours
a day. The temperature of the water in
passing through the jackets of the en-
gines is raised from 65 degrees to 130

outside surfaces of the elements arc
ribbed to increase their heating surface,
as indicated in the plan view in Fig. 2.
The heater serves also as a silencer, the
gases being allowed to expand in suc-
cessive efforts, between the cast-iron ele-

dcgrees, Fahrenheit, and the exhaust
healer raises it from \.V) to 200 degrees.
In the summertime it is not necessary to
r.is8 any water through the heater, and
it is run bone dry. apparently without
any ill effects.

Gas Power in a Manufacturing
Establishment

At the recent meeting of the National
Gas Engine Association, William Weber
related his experience with gas power
in the plant of the Van Dorn & Dutton
Co., manufacturer of commutators and
gears. The power plant consists of a
three-cylinder 175-hp. engine coupled to
a 150-kw. alternator and a four-cylinder
135-hp. engine belted to a jackshaft from
which two lineshafts are belt-driven.

The larger engine has been in use
three and a half years and the smaller
one a little over two years. Both run on
natural gas costing 30c. per 1000 cu.ft.
The larger engine carries full load and
the smaller one about 80 hp. The aver-
age monthly expense is given in the
following table:

lanre Small

Engine Engine Both

Has @ 30c J101.2.'-. $66.00 $167.25

Oil (a 20c 9.00 8.00 17.00

Waste (S. 9c 0.90 1.08 1.98

Eneinecr 95.00

H'Mptr (18 hr. per

month © 18}c.) 3.33

$2S4 . .".6

Mr. Weber is the engineer of the plant.
He also has charge of a stockroom next
to the engine room and looks after the
22 motors used in the factory, the light-
ing, wiring, etc. His duties outside the
engine room occupy about half of his
time.

The plant shuts down at 1 1 :30 a.m.
on Saturdays and the helper's services
are then called into play; the engineer
and helper go over the engines, taking
off the crank-case covers, examining the
bearings, lr)ing all bolts and nuts to see
if they are tight, etc. One exhaust and
one intake valve-cage, with valves, arc
taken out of each engine, cleaned and, if
necessar>', ground, and put back in place.
Each successive Saturday the valves of
another cylinder are taken out and given
the same treatment. Therefore, all of
the valves of the three-cylinder engine
get thorough attention once every three
weeks, and those of the four-cylinder
engine once every four weeks.

All spark plugs and igniters are
changed once a week. The mixing valve
is taken out and cleaned once a month
on each engine.

Once a week ten gallons of oil are
drawn from the crank case of each en-
gine and replaced by fresh oil.

Every six months a!' of the oil is
withdrawn from the crank cases, the
cases thoroughly cleaned and then in-
filled with fresh oil. The oil taken out
of the crank cases is used in some of
the gcar-cnticrs. mixed with screw-cut-
ling nil. effecting a slight saving.

A thermometer is kept in the iacket-
wfller outlet and another one is applied
to the walls of the cylinders next to the
crank cases, to keep posted a« to the heat
there.

95S

POWER

December 26 1911

Refrigeration D^P^rtment

The Non precipitation of Cal-
cium Chloride from Brine
by Ammonia*

At the October meeting of the Ameri-
can Society of Refrigerating Engineers,
in St. Louis, the question was brought
up as to the effect of ammonia leaks on
calcium-chloride brines. Statements were
made at that time that in several in-
stances where ammonia had leaked in-
to calcium-chloride brine the calcium had
been precipitated out of solution by the
action of the ammonia. This precipitate
was said to have been of a pasty nature
and was therefore with difficulty removed
from the brine tanks in which it formed.

It was the author's opinion that calcium
chloride would not be precipitated in
this manner and that the brine in ques-
tion must have contained magnesium
chloride as well as calcium chloride. Al-
so, that calcium chloride would not be
precipitated out of solution by ammonia
unless carbon-dioxide gas was present
in some form. To learn the exact cause
of this precipitation the author has since
carried out some interesting tests, the
results of which are herewith presented.

The first brine treated with ammonia
was made up with chemically pure cal-
cium chloride. It was of 1.2 specific
gravity. No precipitate formed for a long
time and even after a long period this
precipitate was very slight. If all air
could be excluded and, consequently, all
carbon-dioxide gas, there would be no
precipitate at all under these conditions.
The precipitate which does form is due
to a slight carbonation nf the calcium in
solution.

The second brine treated with am-
monia was made up with chemically pure
magnesium chloride and was of 1.2
specific gravity. There was an immediate
precipitation in this brine, the precipi-
tate becoming heavier as the ammonia
was passed in. The brine being made
from chemically pure magnesium chlo-
ride, nothing else than magnesium can
in any way be precipitated from such
a solution. As a matter of fact, this is
just what happened, the precipitate be-
ing magnesium hydroxide.

The third brine treated with ammonia
was made up with equal parts of the
two brines which had been already
demonstrated; that is, one-half calcium

'Abstnrf o' paner ri-nd by Morgan B.
Smith befori' the .\(ni>ricaii Socictv of
UefriKoratliiK Knginoors. New York,

Principles
and operation of
ice making and re-
frigerating plant-
and machinery

chloride and one-half magnesium chlo-
ride by volume, of the respective chem-
ically pure brines. On passing ammonia
into this composite or mixed-chloride
brine there was an immediate precipita-
tion similar to that previously noted in
the case of the chemically pure mag-
nesium-chloride brine. As a matter of
fact, the two precipitates were the same
in composition, namely, magnesium
hydroxide. There would also be a slight
precipitation of the calcium due to the
carbonation of a small amount of the
calcium in solution.

The three experiments show that cal-
cium chloride is not precipitated out of
solution by ammonia, but magnesium
chloride is precipitated. Also, that from
a mixed-chloride brine the magnesium is
readily precipitated by ammonia, where-
as the calcium is not.

It is very evident that a calcium chlo-
ride containing magnesium chloride will
make a brine from which ammonia will
precipitate the magnesium.

Passing on to the commercial chlorides
which are to be obtained on the market
for refrigerating purposes, the fourth
brine which was treated with ammonia
was made up with a commercial chloride
containing 74 per cent, calcium chloride
and 1 per cent, sodium chloride. It was
of 1.2 specific gravity. On passing am-
monia into: this brine there was no pre-
cipitate for a long time. After con-
siderable time there was a slight pre-
cipitation of the calcium due to car-
bonation as was the case with the chem-
ically pure calcium-chloride brine.

The fifth brine to be treated with am-
monia was made up from a commercial
chloride containing 57.62 per cent, cal-
cium chloride, 9.31 per cent, magnesium
chloride and 1.38 per cent, sodium chlo-
ride. Its specific gravity was 1.2. An
immediate precipitation took place when
ammonia was passed into this brine, ex-
actly as was the case with the mixed-
chloride brine made up with chemical-
ly pure chlorides and also in the case of
the chemically pure magnesium-chloride

brine. This precipitate became heavier
as the ammonia was passed in and, as
in the previous cases, was magnesium
hydroxide.

The two commercial brines tested are
typical of the two classes of brine in
common use in this country, and their
behavior in these tests is characteristic
of all brines made up with such chlo-
rides as have been used. The chlorides
on the market vary to some extent in
chemical composition, but not enough to
form a third class.

It can be safely concluded therefore
that the behavior of these brines which
have just been tested is typical of all
brines made up with commercial chlo-
rides. When a calcium chloride contains
magnesium-chloride impurity it will make
a brine from which ammonia will in-
variably precipitate the magnesium out
of solution. This means that with such
a brine there will always be the danger
that with ammonia leaks the precipita-
tion spoken of at St. Louis will occur.

The reaction which goes on when mag-
nesium chloride is precipitated out of
solution as magnesium hydroxide is a
variable independent of the conditions of
temperature, pressure, etc. At times 50
per cent, of the magnesium in solution
is precipitated out of solution. At other
times as high as 97.5 per cent, can be
precipitated out by the addition of am-
monia.

Quantitative E.xperiments

In these quantitative experiments 250
c.c. of the respective brines were used
in each case. The ammonia was passed
in by distillation from aqua ammonia of
0.9 specific gravity.

In the sixth test the brine was made up
with a chloride containing 57.62 per cent,
calcium chloride, 9.31 per cent, mag-
nesium chloride and 1.38 per cent.
sodium chloride. It was of 1.2 specific
gravity and 250 c.c. of this brine con-
tained 8.13 grams of magnesium chloride.
In a series of six tests fully 97.5 per
cent, of the total magnesium chloride
was precipitated out of solution by the
addition of ammonia.

It is well at this time to point out the
fact that the brine resulting after pre-
cipitating out the magnesium chloride,
being so weakened in chloride content,
must possess a decidedly higher freez-
ing point than did the original brine.
There is the possibility, therefore, that
not only will there be danger of plug-
ging up piping, etc.. with the precipitated

December 26, 1911

POWER

959

magnesium hydroxide, but there will al-
so be the additional danger that the
brine will freeze, if not solid, at least
into a thickly congealed mass.

In the seventh test, brine was made up
from a chloride containing 74 per cent,
calcium chloride and 1 per cent, sodium
chloride. It was of 1.2 specific gravity.
Ammonia was passed into this brine in
var>'ing proportions with the same re-
sults, as noted above, with similar brine,
namely, a very slight precipitate due to
carbonation of the calcium in solution.

Some of these tests were carried
through out of contact with the air, with
the result that no precipitate whatever
appeared. When, however, this brine,
saturated as it was with ammonia, was
exposed to the air for some time the
characteristic precipitate due to carbon-
ation of the calcium in solution appeared.

In order that some definite idea might
be had of the extremely small amouiit
of this precipitate due to carbonation, an
experiment was carried through in which
750 c.c. of this brine containing no mag-
nesium chloride was treated with am-
monia distilled from 200 c.c. aqua of
0.9 specific gravity. The resulting solu-
tion, pretty well saturated with ammonia,
was then allowed to stand in a shallow
12-in. dish giving a large surface exposed
to the air. Under such conditions, which
were very severe, in an atmosphere con-
taining carbon dioxide in excess of nor-
mal, a precipitate did appear after 12
hours. This precipitate weighed 0.0150
gram per 250 c.c, the basis of the former
experiments.

When this extremely small precipitate
is compared with that formed under the
same conditions with the brine contain-
ing magnesium chloride, namely, 4.76
grams Mg(OH ):, equivalent to 7.80 grams
MgCl,, it is seen at once that this sec-
ondary precipitation due to carbonation
is an entirely negligible quantity.

It would be advisable for all who op-
erate refrigerating plants using calcium
chloride to acquaint themselves with the
true nature of the chloride which they
purchase. A competent chemist can al-
ways tell when magnesium chloride is
present and can help to avoid such diffi-
culties as have been met with in the use
of chlorides containing magnesium chlo-
ride as well as calcium chloride.

Calcium chloride itself is a very valu-
able material for use in refrigcraiing
plants and, if used intclligenfly, will give
excellent results. Calcium chloride, if
contaminated with magnesium chloride,
will be sure to cause trouble with am-
monia leaks.

Many of these chlorides are called
calcium chlorides. A better name would
be composite or mixed chlorides, or bet-
ter still, calcium-magnesium chlorides,
which would then describe their true
nature.

Operating Ammonia Com-
pressors by Aid of
Thermometers*

In the competent handling of a re-
frigeration plant there are some points
which, if properly taken care of, may
avoid trouble and in any event will be
only beneficial.

No matter how well constructed, the
plant is at the mercy of the operating
engineer; it is a success or a failure ac-
cording to his knowledge. If the plant's
performance is not satisfactory to its
owner, who mostly relies on his engi-
neer, the owner usually demands that a
test be made as to capacity, etc.

Then the manufacturer sends his men
to insert thermometer wells in the suc-
tion and discharge pipes near the com-
pressor and at other places where the
reading of temperatures is of any im-
portance. Preliminary to and during the
test the temperatures of the suction and
the discharge gas are carefully taken at
frequent inter\'als as the manufacturer
regards it of great importance in getting
the best results; indicator diagrams are
also taken to make sure that the valves
are working properly or a piston is
tight, and that the back pressure is so
regulated as to be most suitable for this
particular plant.

If this temperature is so important to
the manufacturer, it is just as important
to the owner; the closer he can run his
plant to test conditions, the better are
his results. How often is the suction-
gas temperature taken by the operating
man, and is he in a position to draw
the proper conclusions and provide
remedies if needed?

In the speaker's own experience in a
fairly large plant the operating engineer
was as good as the average, but it was
found that the ammonia suction gas was
superheated 31 deg. The suction pipe
was not covered and the engineers were
careful not to allow frost to enter the
compressors, knowing that it caused leak-
age around the stuffing-boxes.

Assume, for illustration, that the com-
pressor was a 16x24-in. single-acting ma-
chine, running at 78 r.p.m., with a back
pressure of 1.^.67 lb. The temperature
corresponding to the back pressure equals
0 deg. F. ; the specific volume or volume
of one pound equals 9 cu.ft. and the
displacement of the compressor in cubic
feet per minute equals 435.

Assuming 100 per cent, volumetric ef-
ficiency, the displacement divided by the
specific volume corresponding to the back
pressure results in

435 ^ 9 - 48.33 lb.
that is. the pounds this compressor would
deliver if there were no losses of any

•Absfmrt of pappr rPRil by B N. Frli-il-
Ttinnn at tho HI. Ixiulu mr-rtlnit k( thr
Am<Tlran 8ocl«>ly of nefrUoratlne Rn-

kind. Now, assuming a superheat of 31
deg. F., the ammonia entering the com-
pressor at 31 deg. (instead of 0 deg., cor-
responding to the back pressure), the
question is, how much less is the volu-
metric efficiency?

For each 1 deg. F. increase of tem-
perature, and a back pressure of 15.67
lb. gage, the volume will increase 0.022
cu.ft. Consequently, for 31 deg. F., the
increase will be

0.022 X 31 = 0.682
Therefore the volume, instead of 9 cu.ft.,
occupied per pound of ammonia, will be
9.682, and the compressor will deliver

435 -i- 9.682 = 44.9
a loss of

48.33 — 44.9 = 3.43 lb.
and, figuring 0.4 lb. per ton, 8.8 tons.

By properly insulating the suction pipe
and regulating the flow of ammonia to
the compressor much of this loss would
have been avoided. The operating en-
gineer was perfectly willing to be shown
and at once gave his men the correct
instructions. There are many such cases
and the sooner the engineer learns the
use of the thermometer the better it will
be for both owners and manufacturers.

In a case of the other extreme there
were two compressors, each manipulated
in such a manner that a great amount of
liquid was allowed to enter the cylinders.
The compressors were frosted all over
and the discharge pipe was barely hand
warm. The worst of it, however, was the
fact that this liquid was taken direct
from the ammonia liquid receiver in the
engine room, forming, one might say, a
short-circuit, and interfering very seri-
ously with obtaining results in the cel-
lars and the beer cooling on account
of a rising back pressure up to about 45
lb., even when the machines were run-
ning full speed.

To ascertain the loss of capacity by
using the discharge temperature, as-
sume a condenser pressure of 185 lb.;
the discharge temperature of the gas
taken from test records is about 240 deg.
F. for 15 lb. back pressure, but was low-
ered to 100 deg. by the injection ammonia,
which was lost to the refrigerating outfit.

Taking the compressors referred to
above, having a capacity of about 40 lb.
of ammonia per minute under 15
lb. back pressure (corresponding to
82 per cent, efficiency), the loss
would be 2800 B.t.u. per minute. If the
latent heat is 500 B.t.u., the loss would
be 5.6 lb. Assuming 0.4 lb. per minute,
the loss becomes 14 tons. While the
latter case is exceptional, similar ones
have been found in vertical as well as
horizontal machines.

An operating engineer Is not neces-
sarily incompetent because he docs not
use thermometers, but he would be more
competent if he did. as they teach him
the rclalinno existing between volumes
and temperatures; and when he once

POWER

December 26, 1911

accustoms himself to using this method,
he likes it, and in many cases he can
run the machines slower.

Generally speaking, more mistakes are
made in allowing too much liquid to en-
ter the compressor than the opposite, and
as it is important to give the engineer
some guide to prevent this, the follow-
ing table has been compiled for his in-
struction:

Temperature at

Which Suction

Gas Shall Enter

Compressor, Deg.

Boiling Point
Deg.

+ 3

+ 7
+ 11
+ 16
+ 20

Gage Pressure
12.25
15.67
19.46
23.64
28.24

33.25 20 +2.T

38.73 25 +2,s

44 .72 30 + 3,5

The engineers of the manufacturers
have been of great assistance to operat-
ing engineers, who seldom have access
to the data of the manufacturer. It is to
be hoped that some tables with easily un-
derstood data will be put within reach
of the operating man, as they will make
him more valuable to his employer and
help the manufacturer as well, as in
many instances the expense and time
for tests may be saved.

Steel versus Iron Pipe in
Refrigerating Work*

So called steel pipe is made from
a purer iron than wrought-iron pipe, and,
from an engineering standpoint, is more
desirable as the material is more uni-
form, easier to weld and the finished
product smoother, with no blisters.
Wrought-iron pipe is not regular in qual-
ity or material and the method of man-
ufacture makes it difficult to detect its
defects w-hen it has once been made into
pipe.

Wrought-iron skelp and pipe-steel
skelp, on an average, have the following
physical properties:

Wrought

Iron

Pulled

Pipe

Longi-

Steel

tudinally

Tensile strength, lb. per sq.in .

58.000

46,000

Elastic hinit, lb. per sq.in. . . .

34,000

28,000

Klongation. per cent, in 8 in..

Reduction in area, per cent .

55

25

Wrought iron will vary from 4 to 16
per cent, in elongation while steel is
expected to range between 19 and 25 per
cent. Pulled transversely, puddled iron
seldom gives 35,000 lb. per square inch
tensile strength, and the elongation and
the reduction in areas are proportion-
ately low and variable.

Most refrigerating engineers handle
pipe from 2 in. in diameter down, made
by the butt-weld and lap- weld process;
1'4-in. pipe and under is butt-welded
unless redrawn.

As showing the average of bursting
tests on steel and wrought-iron pipe U^J
and 2 in. in diameter, the accompany-
ing table is supplied by F. N. Speller,
of the Engineers Society of Western
Pennsylvania.

It is common experience that both steel
and wrought-iron pipe can be readily
and perfectly threaded if the cutters
have the proper rake. Dies for thread-
ing wrought-iron pipe require only about
12 deg., while steel pipe should have
about 18 deg. rake, and about 6 per
cent, more power is required to thread
steel pipe.

For ice-making and refrigerating tanks,
where the pipe is constantly submerged
in brine, there is no pitting or cor-

age being less than 2 per cent, at 500
lb. under air test and occurring where
the mill was too economical and cut the
pipe too near the tong end.

When iron pipe is bad, it is very bad,
probably caused by the large variation
in the quality of the material as steel
scrap of various composition is used as
well as badly distributed slag.

Galvanizing steel pipe, with its uni-
form quality of material, absence of slag
and of laminations, is ideal for con-
densers; galvanizing iron pipe is a
source of trouble as the pipe is pickled
or cleaned by hot sulphuric acid, which
eats off the mill scale and slag, some-
times into the interior of the pipe. Fur-
thermore, it stands the air under the

aver.\(;e of bursti.ng te.sts on steel and wrought-iron pipe

Sizes.
Inches

Kind of Pipe

Length,
Feet

.Num-
ber of
Sam-
ples
Tested

Average
Weight
per Foot,
Pounds

Average

Thickness,

Inches

.\verage
Bursting
Pressure,
Pounds per
Square
Inch

.\verage Maxi-
mum Stress per

Square Inch
on Wall of Pipe,

Poimds
(Barlow Fonnula)

U

Standard butt-weld
steel

18.0

10

2.26

0.139

5,808

34.600

li

Standard butt-weld
wrought iron

IS. 5

10

2.21

0.147

4,891

29.800

li

Standard butt-weld
wrought iron

17.5

10

2.21

0.136

5,283

30,900

u

Standard redrawn butt-

15.0

14

2.21

0.136

7,400

44,800

u

Extra strong butt-weld

20.0

11

2.86

0.181

10,640

54,000

li

Extra strong butt-weld
wrought iron

20.0

.10

2.95

0.188

5,895

26,700

2

Standard lap-weld steel.

20.0

10

3.67

0.155

6,645

51,000

Standard lap-weld
wrought iron

20.0

10

3.65

0.152

3,213

(Purchased 25,100
as lap weld but
looks like "butt
weld")

2

Standard but!-we!d steel

19.0

11

3.53

0.153

4.951

43.400

Standard butt-weld
WTOuglit iron

17.5

10

3.70

0.156

3,687

28,600

2

Tubing (4 lb.) lap-weld

21.5

10

4.26

0.178

7.361

47,800

Extra St rong lap-weld

18.5

10

5.01

0.218

7,909

43,300

2

Extra strong lap-weld
wrought iron

20.0

10

4.79

0.206

6,349

36,500

2

Extra strong butt-weld
steel

20.75

10

5.06

0.220

7,661

41,700

2

Extra strong butt-weld
steel

20.5

10

4.91

0 213

8,238

45.900

♦Abstract from paper read by P. DeC.
Ball at the St. I.,ouis meeting of the
American Society of Refrigerating En-
gineers.

rosion, but in submerged condensers
heavy pitting in spots is observed.

It is the writer's personal experience
that submerged iron or steel pipe has
never corroded sufficiently in an ice or
brine tank to cause trouble, and he has
taken out both iron and steel coils after
15 years' service and used them in mak-
ing new coils. Of course, this does not
apply where the pipe is exposed for
several months in the year to oxidization
by salt, air and moisture.

No instance is known to the author
wherein steel pipe is not as good, or even
better, than wrought-iron pipe; 30 per
cent, of genuine wrought-iron pipe has
been found defective and never more
than 7 per cent, of steel pipe, the aver-

water test, is made up into condenser
stands, erected and put into operation.
The ammonia decomposes the spelter
with which the pipe was galvanized, and
then the leaks and the engineer's troubles
begin at the same time.

From 33 years of personal observa-
tion, constructing, erecting and operating
ice-making and refrigerating machines,
absorption and compression types, and
using iron pipe for the first 14 years,
and iron and steel pipe for the next
19 years, the author is convinced that
local conditions only govern the cor-
rosion of pipe and that chemically and
mechanically mild-steel pipe meets the
requirements of the refrigerating engi-
neer in all respects.

December 26, 1911

POWER

9S1

Issued Weekly by the

Hill Publishing Company

John a. Hill, Pres. and Tr^a,-. Rob't McKEAK,Sec^,

503 Pearl Street. New York.

122Sonth Mfchi^n Eoulevartl, Chfcaga

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Name and address of correspondents
must be given — not necessarily for pub-
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Pay no money to solicitors or agents
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Subscribers in Great Britain, Europe
and the British Colonies in the Eastern
Hemisphere may send their subscript ions
to the London Office. Price 21 Shil-
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Entered as second class matter, De-
cember 20, 1910. at the post office at
New York, New York, under the Act
of March 3, 1879.

Cable address, " PowpuB," N. Y.
Business Telegraph Code.

CIRCDLATION ST AT EM EXT

Of this issue 30,000 copies are printed.

None sent free regularly, no returns from
news companies, no back numbers. Figures
are live, net circulation.

Contents page

New Generating Station, Portland.

Ore 942

Massachusetts License I.,aw Revised 946

Notes on Grouting Bedplates 947

Tom Hunter, Hoisting Engineer 948

Efficiency of Reciprocating Engines 950
An Analysis of Some Recent Gas

Engine Failures 954

The Bogert Auxiliary Heater 95G

Gas Power In a Manufacturing Es-
tablishment 957

The Nonpreclpltatlon of Calcium

Chloride from Brine by Ammonia 958
Operating Ammonia Compressor by

Aid of Thermometers 959

Steel versus Iron Pipe In Refrigerat-
ing Work 960

Editorials 961-962

Practical Letters:

Example of Poor Designing..
Plugged Boiler Head .... Oil
Grooves. . . .How He Got a Raise
. . . .Noisy Valve Gear Tappets
....Excellent Steam Charts....
Centrifugal Pump Repair....
Homemade Water Heater ....

Size of Tank Required »«5-!»67

Discussion Letters:

Pothlyn. Pump Doctor. .. .Sand
for Hot Boxes.... Air Comprfs-
sor Running Under. .. .Burning

Fuel Oil Graft Effective

Pressure of a 8 c r e w . . . A
Twenty Four Hour I»g. .. .Trou-
ble with Leaking Tubes 968-971

Pipe Flange Bolting

In considering the question of flanges
for pipe and fittings more often the whole
attention is given to these parts them-
selves and none at all, or very little at
the most, to the bolting. For this reason,
perhaps, the average pipefitter or steam-
plant operator does not fully realize the
importance the proper bolting together
of flanges has in putting up a pipe line
properly.

In the first place, wherever possible,
through bolts should be used, and if the
design of any particular fitting or some
existing condition does not permit of this,
then it will very often pay to so change
the design or condition that this rule can
be carried out. The man in the drawing
room who designs the necessary special
fittings and lays out the work is usually
responsible for the tap and stud bolt as
it is so easy to stick one in here and
there rather than to make some slight
change in the design. A short time spent
in the mill under the direction of a good
master mechanic will, however, soon re-
lieve him of this tendency and he will
see for himself the wisdom of using
through bolts in all cases.

The bolts connecting pipe flanges are
subjected to three distinct loads: that
due to the torsional stress because of the
friction between the threads of the bolls
and the nut; the tension due to screwing
up, and the straining action due to the
pressure in the pipe line. The total stress
or load on the bolt is, therefore, so far
as all practical purposes are concerned,
the sum of these three.

The greatest stress is that caused by
the screwing up of the nut, and cal-
culations regarding it are of little or no
value as the stress is entirely dependent
upon the ludgmcnt of the mechanic doing
the work. A number of tests have been
made on bolts of various sizes and with
different-length wrenches, but the results
have not been uniform. If has been
learned, however, that the load varies
about as the diameter, for the mechanic

will usually graduate the pull on his
wrench proportionally with the size of
the bolt. It was learned also that the
results were more uniform and the loads
a trifle higher when using faced nuts and
co-relating surfaces.

In addition to this tensile stress there
is also considerable torsion taking place
at the same time, and these two stresses
combined have often been so great as to
result in a twisted-off or broken bolt.
Often, no doubt, the combined force ex-
pended in tightening a nut exceeds the
elastic limit of the bolt and will cause
a slight fracture, so that when the pres-
sure is turned on the pipe the bolt breaks.

Since the judgment — and sometimes
the strength — of the mechanic is the only
governing factor for these two stresses,
there is room for a little standardization
with the view to limiting the length of
wrenches to be used on different bolts.
The use of a piece of gas pipe, so often
slipped over the wrench in order to get a
greater leverage, might also be eliminated.

The third stress — that due to the pres-
sure in the pipe — is hardly ever great
enough to cause any trouble. Further-
more, it is automatically regulated, as it
were, for the total load due to the in-
ternal pressure varies with the diameter
of the pipe and, consequently, decreases
as the size and the number of bolts cor-
responding to the smaller sizes of pipe
decrease.

Licen.se Graft in New York
It is a funny thing about New York
engineers that for several years they
should have been nursing a rising indig-
nation, not because they were called up-
on to pay graft when they went after
licenses, but because the "price of li-
censes" had been raised from twenty
dollars, as it was in the good old times
when Power exposed the practice with
the aid of Mr. Van Stccnburg in 1898,
to fifty or more.

For several years fnllowlne the reor-
ganization of the department, consequent
upon our expos£, it appeared to be con-

962

POWER

December 26, 1911

ducted upon an honest basis. Of late
years, however, it has been common re-
port that graft was again being demanded
and in larger amounts than formerly. It
has been impossible to find anybody,
however, who would give definite informa-
tion upon the subject without putting
such restrictions upon the use of it that
it could not be submitted to the attention
of the authorities nor used as the basis
of an exposure.

Recently, William H. Black applied
for a license and was not able to pass
the examination. He was not satisfied
that the examination had been on the
square, and took steps to trap the in-
spectors.

Obtaining money from the Society for
the Prevention of Crime, the numbers of
the bills having been noted, he returned
for a second examination. This money
was handed to a subordinate, who, ac-
cording to reports, said: "I don't want it
for myself; I have to get it for the men
higher up."

The "men higher up" were apparently
satisfied, for Black was reexamined and
received his license.

The Society for the Prevention of
Crime and Commissioner Waldo, of the
police department, set the trap into which
the inspectors fell. The result was that
one branch of the police department
raided another. When the examining
inspectors were arraigned and searched
at the detective bureau, several of the
bills which had been given to Black were
found on one of the inspectors.

The men involved were suspended,
and Commissioner Waldo began an in-
vestigation which led him to conclude
that the boiler-inspection department was
so pregnated with graft that nothing less
than a complete cleaning up of the de-
partment would remedy matters. Con-
sequently, Lieut. Breen, sixteen patrol-
men and four clerks were ousted and
transferred to various stations through
the city. A new boiler squad has been
organized under the command of Capt.
James H. Gillen.

It is reported that Police Commissioner
Waldo will advocate the removal of the
department which has to do with the li-
censing of engineers and the inspection
of boilers from the police department,
and place it in the fire department.

A much better arrangement would be
to allow the licenses to be issued by
the commissioner of licenses on the

recommendation of a board composed of
appointees from the National Associa-
tion of Stationary Engineers, the Inter-
national Union of Stpam Engineers and
a lay member, as proposed in connec-
tion with the revision of the city charter.
The possibility of the perversion of
their opportunities to such base uses
is the best argument which the opponents
of license laws for engineers have to
offer, and if the alleged facts and con-
ditions are established we sincerely hope
that the grafters will receive retribution
commensurate with the immense sum in
which they will in that case have
mulcted the engineers of New York City
and the disrepute which they will have
cast upon governmental supervision of
steam plants and engineers.

Back Pressure Valves

The back-pressure valve is a simple
piece of apparatus which enters into the
installation of nearly every power plant
and which should have attained a high
degree of perfection if time and experi-
ence are to be considered worth anything.
As a fact, however, there appears to be
room for improvement and adaptation
to the more precise service frequently
required of it.

A back-pressure valve is intended to
maintain a constant back pressure on
the exhaust-steam system of a plant re-
gardless of the volume of steam which
may pass through it. If exhaust steam
is used for heating or drying purposes,
there will be a great variation in the vol-
ume of steam used at different times
and the excess steam furnished by the
engine must pass to the atmosphere
through the valve. It is quite evident
that if five pounds pressure is all that
is necessary for the heating or other
processes for which exhaust steam is
used, there is a loss of power when the
pressure rises above five.

The back pressure is a very potent fac-
tor in determining the efficiency of an
engine and the loss occasioned by in-
creasing it unnecessarily will in most
cases amount to a sum entirely incom-
mensurate with the price of the back-
pressure valve. If this impairment of the
efficiency came when the exhaust steam
was being used it would be immaterial,
but it is occasioned by the effort of sur-
plus steam to escape to the atmosphere,
when increased efficiency on the part of
the engine would have its full effect.

With some of the simpler forms of
valves in the sizes and proportions in
which they are usually installed, the
pressure, when it is necessary to dis-
charge all of the steam to the atmosphere,
will sometimes rise to nearly twice that
at which the disk begins to lift, with the
result that added work is placed upon
the engine with an absolute loss. It is
frequently necessary to use a valve of
two or more times the area of the pipe
in order that the total lift shall be small
and that the effective pressure remain
constant or nearly so.

With modern systems of heauug and
drying, it is possible to secure results
at one and two pounds pressure that
were impossible before with five pounds,
and it becomes even more necessary to
operate within narrow limits if the best
results are to be obtained. The combina-
tion of a perfectly balanced valve which
has no tendency to open at any pres-
sure and a damper regulator having a
large diaphragm sensitive to within one-
quarter of a pound has insured close
working and a constant pressure in the
practice of one of our correspondents.
This combination is more expensive than
any self-contained back-pressure valve,
but the price is wholly unimportant when
one considers its earning capacity.

In those systems where there is a very
great variation in the volume of steam
used for industrial purposes the com-
bination before referred to, together with
a similar combination for admitting live
steam to the system, can be made to
work within one-half of a pound, so that
the pressure on the low-pressure system
will be constant whether five per cent
only of the steam is being used or all
of the exhaust, together with a very con-
siderable amount of live steam. It is a
valuable combination in those cases
where heating is done at practically at-
mospheric pressure.

It is possible that some of the manu-
facturers of back-pressure valves may
find it profitable to make available a
self-contained valve operating upon some
such principle, or at least which will
maintain a constant pressure in the ex-
haust-steam system under a widely vary-
ing rate of discharge.

Did you notice that ir the big Delray
boiler test the highest capacity, 214.8
per cent, of the normal, was reached
when the furnace was making 16.5 per
cent, of CO:?

December 26, 1911

POWER

963

Weir's Rotary Air Pump

Several designs of rotary air pumps
suitable for use in conjunction with con-
densers and adapted to be driven by a
high-speed electric motor or steam tur-
bine have, according to The Mechanical
Engineer, recently been patented by Wil-
liam Weir, of G. & J. Weir, Limited,
Cathcart, Glasgow. Fig. 1 is a plan view
of a rotary displacement pump of the
gear-wheel type adapted for use as an
air pump with the top plate and suction
connection removed, and Fig. 2 a sec-
tional elevation on the line Z — Z. A sec-
tional elevation of a pump similar to that
shown in Figs. 1 and 2, but adapted for
use as a dr\'-air pump, is shown in
Fig. 3, and Fig. 4 is a plan view of a
combined wet- and dry-pump set.

extending radially over the ends of the
wheels as shown. An opening H Is
formed in this yoke above the meshing
point of the wheels and serves as a suc-
tion inlet. The discharge chamber of
the pump is constituted by the casing D,
a pipe connection J being provided for
the outlet of the air. This connection is
so arranged at the top of the casing
that the entire casing can be filled with
water, which thereby acts as a seal for
the suction chamber F and stuffing boxes,
thus preventing any leakage of air. The
direction of rotation of the gear wheels
A is such that they sweep out the air
from the suction chamber F through the
opening H and carry it past the yoke G
and discharge it into the sealing water
in the casing, whence it escapes through
the discharge pipe /.

Referring first to Figs. 1 and 2. the
pump comprises two toothed-gear wheels
A meshing with one another and mounted
on parallel shafts B C in a closed cas-
ing D. The ends of the shafts pass out
of the casing through stuffing boxes, the
shaft n being supported at one end by
a bearing, the other end thereof being
coupled to a motor £ for driving the
pump. The shaft C is supported in bear-
ings at each end. The suction chamber
F, at the top of the pump, is provided
with a flange for connecting to the con-
denser, and with a yoke piece G fitting
circumfcrentially on the gear wheels A
and extending from a point slightly be-
low the meshing point of the wheel teeth
approximately over one-quarter of the
circumference of the wheels, and also

In Fig. 3 is shown a pump similar to
that in Figs. 1 and 2, but particularly
adapted for use with a condenser as a
dry-air pump. In this construction two
additional longitudinal shrouds K are
arranged around the circumference of
the gear wheels /.. so that the space at
the bottom of the casing M is isolated
from the discharge chamber N ai the top
of the casing. The scaling water of
the pump is thus compressed in the bot-
tom of the casing, and as its temperature
rises in course of working, it may be
advantageously passed through a cooler
O and returned through a jet P into the
suction chamber K. An adjustable by-
pass may also be fitted as shown, en-
abling a certain proportion of the water
to return to the discharge side of the

pump without passing through the cooler
O. This bypass consists of a chamber S
formed on the outside of the casing M
and communicating therewith through the
bottom opening T and the top opening
Uy this latter opening being regulated by
a screw-down valve as shown. A dry-air
pump of this kind may advantageously
be combined with a wet pump, which
may be a centrifugal pump mounted up-
on the same shaft and adapted to with-
draw the water of condensation from the
condenser; or alternatively as shown in
Fig. 4, instead of the centrifugal pump
a second pump V of the gear-wheel type
may be contained within the casing of
the dry pump H' and mounted upon the
same shafts, but separated therefrom by
a partition .Y. The dry pump if neces-
sar>' may be at a lower temperature than
the wet pump.

It is usual to inject a certain amount
of cold water into the suction pipes and
chambers of dn'-air pumps to condense
the vapor and to absorb the heat of com-
pression. In dry-air pumps of this type
such injection water may be dispensed
with, as the water admitted into the suc-
tion chamber as leakage serves the same
purpose; thus it is unnecessary for the
suction yoke to fit very closely over the
gear wheels, as this water leakage is an
advantage. Further, in cases in which
a certain amount of liquid is also pass-
ing through the pump, the gear wheels
are formed with teeth of a helical or
double helical shape (see Fig. 4) to al-
low the liquid entrained between the
teeth to escape longitudinally. The suc-
tion may be increased by means of a
steam jet which may be of the Parsons
augmenter type, such steam being con-
densed by a jet of water supplied by
water circulating through the pump and
a suitable cooler.

In the pumps described for each revo-
lution of the wheels the displacement
or suction will approximately be the cir-
cumference of one wheel multiplied by
the depth of the tooth, less the amount
of leakage at the circumference and ends
of the suction yoke, and such leakage
for any given difference of pressure will
be a constant, and accordingly represent
a very low percentage of leakage when
the wheels are running at high speeds.
Further, any portion of the gear wheels
may be guarded by cover plates to mini-
mize the surface friction of the wheel
teeth, which rotate rapidly in the case. It
is also evident that the pumps may be
utilized for withdrawing the entire pro-
duct from a surface condenser, compris-
ing the condensed water, air and vapor,
and the use of the pump is not neces-
sarily rcitricled to the pumping of the
air and aqueous vapor alone. In such
cases the sealing water will be the dis-
charged condensed water, and the capa-
city of the pump will accordingly be
governed by the temperature of such
water.

964

POWER

December 26, 1911

Rockwells Automatic Engine
Stop and Speed Limit

A aew automatic engine stop and speed
limft, illustrated herewith, has recently
been patented by H. R. Rockwell, 209
Spring street, Alton, 111. It is com-
posed of a governor which is fitted with
a rocker arm, weight and detachable
lever.

In the drawing is shown a flywheel in
which is inserted a split stud fitted

pawl D, close the circuit through L and
M and stop the engine.

This appliance simply disconnects the
governor from the rocker arm, thereby
relieving the governor of all shock and
jar. It requires no alteration of the gov-
ernor except substituting the lower rod
connection for the slotted link and ex-
tending the pin to carry the latch hook.
This stop is very simple and can be
applied to any Corliss or other engine
having a liberating valve gear.

Engine Stop and Speed Limit

with a spring having a weight attached
to the outer end. At a convenient point
a switch is placed on which is fitted an
adjusting screw which is used to regulate
the speed limit of the engine. There are
also arranged a pawl, switch blade, etc.

The operation of the appliance is as
follows: If the electric circuit is closed
by any means through the battery A,
it will energize the magnet B. This will
attract the armature C and release the
weight D which will fall on latch hook E
and detach it from slotted link F. The
rocker arm will then descend to the stop
C, which will bring the safety cams H H
into a position to prevent the steam hooks
from engaging with the catch blocks on
the steam-valve stem. The engine may
also be stopped by closing any of the
switches in the line, or by the speed-
limit appliance.

When the speed limit operates the
weight J is thrown out by centrifugal
force, in proportion to the rotative speed
of the Rywheel, but the adjusting screw
on the limit switch is so set as to allow
the weight to just miss the screw K when
the engine is running at normal speed.
Should the speed accelerate from any
cause the weight will fly out further and
striking the adjusting screw will trip the

Green's Temperature Pendants

The Green Fuel Economizer Company,
Matteawan, N. Y., has perfected a sys-
tem of determining the temperature of
the gases by using the tensile strength
of metal pendants instead of the melting
point as the true indication of tempera-
ture. The pendants are made with a

In actual use, the pendants are hung
upon a wire hook, which is introduced
into the flue with the pendant at the de-
sired point, beginning with the lowest
tem.perature pendant, and proceeding
until the one is found w'hich will not fall
off after five or ten minutes' exposure.
The flue-gas temperature will then be
somewhere between the temperature
marked on the last pendant and the next
to the last pendant used.

Pendants for three temperatures have
been perfected, namely, 425, 500 and
550 degrees Fahrenheit, representing re-
spectively the temperature at which the
use of the economizer is justified with
coal at commercial prices, the tempera-
ture at which an economizer is a good
investment in all cases, and the tem-
perature at which neglect to install an
economizer becomes waste.

Three tables have been calculated for
use in connection with these pendants.

Piston Handling Clamp

The accompanying drawing shows an
engine piston-handling device so designed
that the piston will hang vertically when

Cla.mp for Handling Pistons

removed from the cylinder. It is the in-
vention of J. G. Koppel, 192 West David
street, Montreal, Can.

Green's Temperature Pendants

large body, having a certain definite
weight, suspended from a narrow neck,
as shown in the accompanying illustra-
tion. The composition of the metal may
be varied and the cross-section of this
neck is adjusted until the body of the
pendant will pull the neck in two and
fall at some desired temperature.

Referring to the illustration, A is an
engine piston; B is the main lever of the
piston clamp; C is a top lever and D is
a triangular block. The balancing pins are
showTi at E and the adiustable bottom
clamp at F. The bottom counterweight
rod G supports the counterweight H. The
device is used as shown.

December 26, 1911

P O Vt' E R

965

Example of Poor Designins^

The station here described was buih
to supply light to a town of about 60(X)
people and to furnish power for a street-
railway line. The load was not expected
to run over 400 horsepower for the first
few years, with variations running much
below that figure a large part of the time.

Fig. 1 shows the general arrangement
of the driving and generating machinery;
there being water available for certain
periods, the plant had both steam and
water power.

As may be seen, the two waterwheels
are belted to the jack shaft and con-

possible to run half of the shaft at a
time, this work could have been done
during the day.

It will be seen that an engine was pro-
vided at each end of the shaft, also con-

case it was necessary to do any repairing
inside the wheel cases it was impossible
to shut the head gates on account of the
matter caught under them.

A further drawback was that there
were no shut-off gates placed just in
front of each wheel so that one could not
be examined without stopping the other.
It will be apparent that had the head
gates been placed inside the spillway so
that only the water required for power
would pass through them, the danger of
refuse collecting would be much reduced.

The different floors and the hight of
the generator floor above the wheel pit

Fig. I. Layout of .Apparatus

Fic. 3. Cross-section of Plant

nected by friction clutches so that either
one or both may be run as desired. The
shaft is 70 feet long and solid through-
out so far as cutting it into parts while
in motion is concerned, and there is no
space left between the quill bearings for
the pulleys driven by the waterwheels to
put in a clutch by way of improvement.
In consequence of this arrangement, con-
tinuous service depended upon there be-
ing no breakdowns of the shaft or hot
bearings.

This arrangement entailed a waste of
power also, for during the day one of the
250-kilowatt generators was run for the
railway load and one of the smaller ma-
chines for the day lighting load, and
there was hardly ever any need of run-
ning the whole line during periods of
light load. Another bad feature was that
the drive pulleys for the generators did
not run on quills but on cast-iron bush-
ings with babbitt linings, and as these
were connected by friction clutches, the
side pull of the clutch soon wore the
bushing so that the pulley ran out of
line. On an 84-inch pulley with a 24-
inch face the effect of this action can
be imagined. Also, in order to repair
the bushings in these pulleys, it was
necessary to shut the shaft down, which
could only be done between the hours of
12 midnight and 6 a.m.; had it been

nected by a friction clutch. The bad
feature about this arrangement was that
the engines were too far removed from
each other and were about 8 feet below
the generator floor. This kept the man
who was operating the station on the
jump most of the time, a fact detrimental
to good service.

In Fig. 2 is shown the manner in which
the water flowed to the wheels. The lo-

1

iiT n m

are shown in Fig. 3. In the first plan
the governor for the waterwheels was
placed on the gallery 30 feet below the
upper floor; this was later moved to the
main floor so as to control the wheels
without losing sight of the switchboard.
It was necessary to make the engine
and generator room of this station very
large on account of the space required
for the belt drives; also, one of the en-

Forthay

^■,-.|-.'>n-T

Fir,. ?. Plan of Forebay and Wheel House

cation of the head gates caused all the
water supplying the wheels, and also the
surplus flowing over the spillway, to pass
through a comparatively small opening.
As a consequence, in times of high water,
when the river was full of all kinds j>f
debris, if was a common occurrence for
these gates to become so plugged uv that
barely enough water would pass through
for the operr.ion of the plant and in

gincs had to be a long distance from the
boilers. If vertical wheels direct-con-
nected to generators, with the generators
placed on the level of the main
floor, had been installed, one driving a
direci-ciirrcnt machine and the other an
alternator, and had the engines been put
next to the boiler-room wall and con-
nected lo two machines on the same shaft
so that one engine could furnish power

966

POWER

December 26, 1911

for both the lights and the railway, all
the belting, pulleys and shaft would have
been unnecessary. Furthermore, the
plant could have been made much more
compact and easier to operate, and
the first cost would have been less.

This station was built in 1903 and
while a large amount of money was spent
on the original installation, it was prob-
ably one of the most difficult plants of its
size to operate successfully in the coun-
try, because of the lack of common sense
exercised in its design.

G. H. Kimball.

East Dedham, Mass.

Plugged Boiler Head

Some time ago a firm of manufacturers
placed an order for a horizontal return-
tubular boiler with a firm of boilermakers
who had a reputation of turning out a
first-class boiler. About nine months
after the boiler had been installed, the
engineer noticed a leak in the head that
had the appearance of a crack. He
promptly notified the inspector of the
insurance company who was carrying

Where Tube Sheet Was Plugged

the risk, and he found that the supposed
crack was a plugged tube hole, located
at the point indicated by the dotted circle
in the accompanying illustration.

A mistake had been made by the boiler-
maker who had cut out the tube holes, and
afterward the hole had been tapped,
threaded and countersunk. A plug had
been screwed in, cut off and afterward
riveted. This had been carefully filed
and the file marks removed by scraping.
The whole was then painted, making de-
tection almost impossible until the leak
showed it up.

In following up the case, to see who
was responsible for this job, it was found
that the finn who built the boiler knew
nothing at all about it. The shop fore-
man denied having ordered it done, and
the shop inspector had passed the boiler
without knowing anything about it. Finally
the man who had laid out the head ac-
''powledged that he had made the mis-

take and had taken this way of covering
it up, believing that it would never be
detected.

W. G. Walters.
Stratford, Can.

Oil Grooves

A power plant which had been running
for some time had four engines fitted
with bronze crank brasses. All of the
crank bearings were running hot. In a few
days after one set of crank brasses had
been removed and oil grooves were cut in

Oil Groove in Eccentric

them, this bearing was running as cool
as any. Ofl grooves were then cut in
the brasses of all of the engines and they
are now running properly. The oil
grooves remedied the trouble as they
placed more surface of the journal in
contact with the lubricant

An eccentric having a diameter of 24
inches was running at high speed and
pulling a heavy valve. It gave trouble
continually by working loose on the shaft,
even though clamped with two setscrews.
Oil grooves were cut as shown in the il-
lustration. The strap was lined with
babbitt and upon starting up no further
trouble was encountered. Unless the
liners between the two sections of the
strap are properly placed the strap may
spring and stick. The liners should cover
the entire surface of the lug. Hot ec-
centric straps are caused as often by this
defect as by poor lubrication.

C. R. McGahey.

Baltimore, Md.

How He Got a Raise

I am employed by a firm which has
plenty of money but looks upon the en-
gineer as a necessary evil and has never
thought of giving him a raise. I had
asked the manager twice for more pay
and got no satisfaction and I gave him to
understand that I was dissatisfied.

I kept on the lookout for another job.
A week later an article came out in
Power, on the first page, called "Hope."
I read it and decided to frame it and
hang it so that when the manager got
rubbering around, it would either be a
case of getting fired or getting a raise.

That evening I clipped the article and
had it framed and the next morning hung
it up in the engine room.

About two hours later the manager
made his daily round and spied "Hope"
hanging on the wall.

He read it and walked out without say-
ing a word.

Saturday, which was also pay day,
came and to my delight the article
"Hope" with a 35-cent frame brought
me a S3 a week raise.

Edgar G. Schindler.

Roxbur\', Mass.

Noisy \^alve Gear Tappets

About a year and a half ago I took
charge of a large, new mill steam plant,
one of its engines being a 2200-horse-
power, cross-compound Corliss engine,
equipped with the Brown valve gear.
For over a year the valve gear ran very
quietly, but during the last few months
the tappets have made considerable noise
as they fell into place. The noise was
more pronounced on the low-pressure
side, where the parts are large ind heavy.
To stop the noise, I first tried a leather
washer under the tappet bolt-head with

Spring on Valve-gear Tappet

poor results, as the leather soon wore
out and the tappet block dropped too
low. Rawhide was not much better.
Frequent applications of cylinder-oil
would stop the noise as long as the oil
lasted, but this method was inconvenient,
and made a mess of the valve gear.

I effectually stopped the noise by using
a flat spring, as shown in the sketch. The
spring is of steel, and is very simple to
make and attach. I put two on during
one noontime shutdown. The thumbscrew
permits a close adjustment, and if the
tension is right, the tappet will drop
quietly into place. Too much tension will
prevent the tappet from dropping low
enough to permit the latch to hook on. I
have used the springs for some time and
they work to perfection. The length of
the spring depends on the size of the bell
crank.

J. Johnson.

Fall River, Mass.

December 26, 1911

POWER

967

Excellent Steam Charts

The accompanying illustrations are re-
productions of photographs of two steam-
chart records taken in my power plant
on October 24 and 25. Can anyone beat

flanged and drilled for bolts. These
patches were bolted on and a cement
grout was poured between the two cas-
ings.

On the underside of the pump, be-
tween the supporting lugs and around

Can You Beat These Steam-pressure Records':

them? Steam was generated in four
water-tube boilers.

E. Stanley Thomas.
Fremont, O.

Centrifujfal Pump Repair

The casing on the centrifugal pump of
a suction dredge gave out. The pump
had a 22-inch discharge and the material
that passed through it varied from clay
silt to coarse gravel and occasional
boulders. One of the latter had been
taken in and slammed a 7x1 2-inch ir-
regular piece out of the rim.

the outlet, a wooden trough or box was
built to leave a clearance of about 6
inches between the sides and bottom and
the pump. This was filled with cement.

After being patched in this manner
the pump was run for some months be-
fore being replaced by a new one.
Thomas H. Heath.

Seattle, Wash.

Homemade Water Heater

I am engineer for an Indian school
which has a capacity of about 200 per-
sons, including the Indian children and

"' I^L^ij'"—

Method of Repairing the Pump Casing

An examination showed that the cas-
ing had worn from a thickness of about
2 inches to a thin shell; in some places
it was almost through. A new pump
was not at hand and time was precious.
Therefore three cast-iron segments, in
two parts each, were made with a radius
of about 4 inches greater than the up-
per pump casing. Holes were drilled to
suit the studs on the side flanges and
longer studs were substituted for the
regular ones. The joint where the two
parts of each segment came together was

nected the live-steam main into the top
of the tanks, running the pipes nearly to
the bottom and I also connected the
steam main into the sides of the tanks
to help the circulation. As the water
supply is under a constant pressure of

the instructors. Formerly the hot water
for bathing and domestic purposes was
furnished to each building by a small
heater and tank. This arrangement was
not very satisfactory, as it required from
four to five hours to heat the water and
continuous attention, the healers being
small and not of the coal-magazine type.
I removed two of the tanks to (he
power house, connected the cold-water
inlet at the bottom, and the hot-water out-
let at the top of the tank, as shown in
the accompanying figure. I then rnn-

Arrancement for Heating Water with
Live Steam

40 pounds per square inch, I placed a
reducing valve on the steam main, allow-
ing only 45 pounds of steam on the tanks.
A safety valve is also provided to relieve
the tanks of overpressure at any time.
Although the water is carried over 300
feet before it is used, the scheme works
very satisfactorily at all times.

Hugh L. Russell.
Keams Canyon. Ariz.

Size of Tank. Required

A stream of water A runs 6 miles per
hour. A tank B is immersed in the river
and a 2-inch pipe 50 feet high is con-
nected to the tank.

How High will the Water Rise in the

2-iN. Pipe?
What size of tank will be required to
force the water out at the lop of the 50-
foot pipe? Will a check valve be neces-
sary in the 2-inch pipe?

H. S. Fitzgerrei I
I. OS Aneelcs. Cal.

968

POWER

December 26, 1611

r— ^

Potblyn, Pump Doctor

An article published some time ago
under the above title concludes with the
query: "Why will an air pump work with
a vacuum in the suction pipe while a
boiler-feed pump will not take water
from a heater in which there is a vac-
uum?"

Briefly, the reply would be that an air
pump has less clearance than a feed
pump and has to deal with water at a
lower temperature than that delivered
from a heater.

Perhaps the commonest and most effi-
cient type of air pump (apart from the
Hdwards) is the single-acting vertical
type with head and foot valves as well
as a valve in the bucket. Fig. I shows
diagrammatically such a pump. The foot
valve is closed because the pressure in
the condenser is less than that in the

Comment,
criticism, suggestions
and debate upon various
arfic/esjetters and edit-
orials which have ap-
peared in previous
issue's

ume swept by the bucket or the foot
valve will not open at all. With 5 per
cent, clearance the foot valve would open
at approximately one-third of the stroke
and the remaining two-thirds would be
employed in reducing the pressure in
the condenser.

On the downstroke, as the volume be-
low the bucket decreases the pressure
increases until first the pressure exceeds
that in the condenser when the foot valve

I

t

f

1

A A
1 1

—>

"■

L

ond at H, and in the third at K, where
X y is the stroke.

The action has been followed out as
for the air pump pure and simple, but in
actual practice an air pump has to deal
with water as well as air. This fact is
of the greatest importance as by prop-
erly arranging the connections the water
may be caused to fill the clearance spaces
and thus virtually reduce their volume
to much less than would be practicable
by any other means.

A boiler- feed pump working with a
heater, the temperature of the water is
an important consideration and limits
the vacuum or lift against which a pump
will draw, apart from the question of
clearance. Suppose it is required to lift
the water 12 feet; this is equivalent to
pumping against a vacuum of 5 pounds
or drawing from a vessel in which the
absolute pressure is 10 pounds per square

Fig. 1

-Condenser Volume — ->j |<: Swept Volur

L. /^'ir Pump-

FiG. 2

FiG. 3

clearance space between the foot valve
and the bucket; the bucket valve is also
closed because there is a head of water
on it. As the space under the bucket
increases the pressure falls in inverse
ratio, and when the pressure has been
reduced to something less than that in
the condenser the foot valve opens, the
pressure continues to fall, but the rate
is now much less because the clearance
has been increased by the condenser vol-
ume. This is shown in Fig. 2 where
A BC n is the clearance, CDEF the
condenser volume and A B G H the vol-
ume swept by the air-pump bucket. If
the pressure in A B C D is 16 pounds
absolute at the commencement of the
stroke and that in the condenser 2
pounds, the foot valve will not open until
,eight expansions have been effected; that
is, until the bucket has swept through
a volume equal to seven times A B C D.
The clearance volume therefore must not
be more than 14''- per cent, of the vol-

closes, and then exceeds that above the
bucket when the bucket valve opens.
After this the rest of the stroke is oc-
cupied in transferring the water and air
from one side of the bucket to the other.
The point at which the bucket valve
will open depends on the clearance space
between the bucket and the head valve.
Assuming the weight of water on the
valve and the resistance to the opening
of the valve itself to be equivalent to a
pressure of 1 pound per square inch, it is
evident that the bucket valve will not
open till the pressure below the bucket
is 1 pound per square inch more than
that above it. Now the pressure on the
underside will approximately retrace the
line shown in Fig. 2 while that on the
top side will follow a line such as A B,
A C OT A D, Fig. 3, which corresponds
with the clearances between the bucket
and the head valve of 5, 7K> and 10 per
cent, respectively. In the first case the
bucket valve would open at G, in the sec-

inch. The boiling point at this pressure
is 190 degrees so that if the feed water
were at a temperature approaching this
the pump would not lift it and the pump
would become steam-bound. In order to
approach the theoretical limits of tem-
perature and vacuum a pump would be
required having much finer clearances
than the ordinary feed pump, which is
constructed chiefly with a view to strength
and simplicity.

A. C. Watts.
Manchester. England.

Sand for Hot Boxes

The advocates of the use of sand to
cool hot hearings have not told the read-
ers the why of the remedy, and before
trying sand instead of other remedies
■which are believed to be better, it would
be interesting to many to know just why
sand will cool a hot box.

December 26, 1911

POWER

969

It is well known that any abradant, of
which sand is a good specimen, when
used between two sliding or rolling sur-
faces will cause friction, and friction
in turn produces heat.

If there is a hot bearing, of course it
is a case of cause and effect, friction
being the cause and heat the effect.

I do not believe that any engineer, as
a result of proper experience and knowl-
edge, would use a cause to abolish its
own effect.

This reminds me of when I took my
first smoke of tobacco. My boy chum
told me to take another smoke; it would
make me well and I would never be sick-
ened by tobacco again. I was not con-
vinced of his remedy any more than I
am now of sand being the proper thing
for a hot box.

If conditions will not permit of any
other remedy, then sand may be used; it
will wear away the babbitt and journal
and in this way produce clearance be-
tween the journal and the box anJ allow
the oil to flow around the journal. But
the sand and babbitt will fill up the oil
grooves and then it will be necessary
to take the bearing apart, scrap it and
cut new oil ways. Sand does not direct-
ly cool hot boxes; its effect is indirect.

I always cooled hot bearings by back-
ing off the cap nuts to give more room,
then applying more oil and a little graph-
ite, and water if necessary and conditions
permitted it. I found that soap and water
were very effective as the soap acted as
a lubricant while the water carried off
the heat by convection, the soap being
washed out of the bearing with clean
water at the end of the process.

James W. Blake.

New York City.

If a box or journal is exceedingly hot,
take a thin mixture of graphite and cyl-
inder oil, pour a little into the box and
have a can of kerosene handy to pour
on to wash out all foreign particles and
to cut the gum, should there be any.
Cold water can be used providing the bo\
is not too hot; otherwise it will injure
the brass or babbitt lining and make it
rough. If this is not scraped at the first
opportunity it will continue to give
trouble. The safest method is to use
oil mixed with graphite, enough to just
change the color of the oil. Then, use
the kerosene as I have stated.

At the first opportunity examine the
box and journal and look for the cause
of the trouble, for sometimes there may
still be an obstacle there to cut and in-
jure the shaft and the box.

I have never tried the sand method, but
I think one should have the sand within
himself to meet the unforeseen, which
oftentimes we are compelled to meet.

W. F. HURD.

Bellefontainc. Ohio.

I have noticed in the recent issues of
Power different engineers' views about
sand for cooling hot bearings. Space in
Power Is too valuable to be taken up
with such a subject. Why not whitewash
coal to prevent smoke? A revolving shaft
or any piece of metal in motion must be
kept separated from its support; natural-
ly this is accomplished with a thin film
of oil. If one adjusts a bearing so close
that oil cannot get between the sur-
faces, the surfaces will get too inti-
mate with each other and tend to seize.

A grain of sand of the finest quality
is larger in diameter than the thickness
of the film of oil between the two bear-
ings and is also harder than the babbitt
metal. Naturally the sand will bed it-
self in the babbitt and cut or scratch the
shaft and make it rough. Every engine
builder advises in his catalog, the use
of a clean, high-grade oil, well filterpd.
Place the engine in a clean engine room.

We have some valuable sand banks
around Danville, but I am yet to hear
that the Standard Oil Co. has taken any
options on them.

Oaks Kyger.

Danville, III.

Air Compressor Running
Under

On page 673 of the Oct. 31 issue,
John S. Leese gives a number of illus-
trations showing the directions in which

Running Corliss Engine with
One Steam Valve

I was interested in C. A. Read's letter
published several weeks ago, in which
he explains how an engine of the Corliss
type was operated for a time with the
head-end admission valve removed. He
showed an indicator diagram supposed to
have been taken from the engine while
operating under the conditions described.
It appears to me that there is a "screw
loose" somewhere, or else all of the con-
tributing conditions and data concerning
this test were not given in his letter.

In the first place, I assume that the
engine was of the single-eccentric type,
with the eccentric set at 90 degrees, plus
the angle of advance, in advance of the
crank. If such was the case, it would
be impossible for a cutoff to occur after
the piston had traveled through one-half
of its stroke, because the motion of the
disengaging link or hook is oscillating
and evidently cannot be released by the
trip after it has started its return stroke.
Therefore, if the load on the engine be-
comes so heavy that the governor moves
the trip so far that it will not be struck
by the hook before the reverse motion
of the hook begins, release of the hook
will not take place at all.

In such a case the admission valve
would be closed as if positively con-
nected to the admission crank, the same
as the exhaust valves.

the forces act at the crossheads of dif-
ferent types of air compressors. In Fig.
1 the directions as he gives them hold
good only during the first half of the
stroke, when the pressure in the steam
cylinder is at a maximum and the pres-
sure in the air cylinder is at a minimum.
During the last half of the stroke the
steam pressure is falling and the air
pressure is rising. Now the flywheels
give up some nf their stored energy and
the forces at the crosshcad act down-
ward.

In Fig. 2 the forces at the air-end
crosshcad will be upward instead of
downward, as the arrow points, and this
direction will not change as in Fig. I,
but will always be upward so long as
the rompressor runs in the direction of
the arrow on the crank disk.

GEORr.e Dreybr.

Cibsonburg, Ohio.

Referring again to the diagram, I note
that cutoff does appear to take place on
the crank end, and that it occurs long
after the piston has passed the h.ilf
stroke. It is also strange that the com-
pression indicated on both the crank and
the head end docs not appear lo be as
high as one would expect to find with an
engine working under such conditions of
high terminal pressure.

Mr. Read states that the engine was
started from the usual head-end position.
Of course, it would start from that posi-
tion, as the instant the throttle was
opened the full boiler pressure would be
applied lo the piston direct, thus causing
the engine to siari. Then, just as the
piston rebelled the crank-end center, the
crank-end adniissinn valve would begin
to open and admit boiler pressure to thai
end. and at the same lime as the pl«
Ion started its return stroke, the hcsd

970

POWER

December 26, 1911

end exhaust valve would open and al-
low the steam to blow direct through
the cylinder from the steam main to the
exhaust pipe. Then, as the piston neared
the head-end center, the head-end ex-
haust valve would close for compression,
thus allowing no further escape of live
steam which, with the head-end steam
valve out, would always be present at
boiler pressure in the head end. Con-
sequently, a balanced condition would be
effected, which would mean as much, or
perhaps more, pressure on the head end
than on the crank end, because the
crank-end steam valve would be closing
as previously described, which in turn
would be cutting down the steam supply
to the crank end and would therefore
probably bring the engine to a stop, since
the speed attained in one revolution
would hardly be sufficient to store enough
energy in the flywheel to carry the crank
over the head-end center.

H. B. Ball.

San Jose, Cal.

C. A. Read, in a recent issue,
showed an indicator diagram taken
with the admission valve removed
from the head end. When the head-
end exhaust valve opens, the steam
rushes straight across the steam chest
to the exhaust passage; therefore the
back pressure is reduced somewhat be-
low the pressure in the steam chest on
the forward stroke and some work is
done in that end.

If the exhaust valve should be dis-
connected and fastened shut, there would
simply be a pumping of steam into and
out of that end of the cylinder, with no
work done aside from that due to fric-
tion of the steam in the steam passage.

In the issue of Feb. 2, 1909, there is
a letter from me showing the effect upon
Ihe steam distribution in the low-pres-
sure cylinder of a cross-compound Cor-
liss engine, because the exhaust valve in
one end had been put in upside down.
This had just the same effect as though
the exhaust valve were disconnected and
fastened shut.

A. L. Westcott.

Columbia, Mo.

Some time since there was an interest-
ing letter in Power from C. A. Read
about running a Corliss engine with the
head-end valve removed.

Mr. Read asks if the engine would run
with the other steam valve removed, and,
if so, what would be the appearance of
the diagrams secured under those con-
ditions.

I believe the engine would start itself
and run with the other valve removed if
the exhaust valves were not interfered
with, for, although Mr. Read says the
engine could not be started by admitting
steam to the crank end, I believe it
would have started had the crank-end

valve been removed also. Then the crank
port would have been wide open the same
as the head port, with the crank exhaust
valve closed and the head exhaust valve
wide open; thus the steam pressure on
the head end would have been reduced
below that on the crank end due to its
blowing right through the cylinder into
the exhaust.

If Mr. Read's diagrams were taken
with an 80-pound spring, there was a
difference of about 40 pounds pressure
between the forward and return strokes
of the piston on the head end. This
variation of pressure was accomplished
entirely by action of the exhaust valve,
the steam port remaining wide open
throughout the revolution.

Consequently, I would expect the en-
gine to run with both steam valves re-
moved and to carry some load. It should
produce a diagram from the crank end
similar to that of the head end, as shown
by the figure in Mr. Read's letter.

Charles F. Clark.

Hartwick, N. Y.

Burning Fuel Oil

Replying to D. A. Steiner's query in
the November 7 issue, I offer the fol-
lowing:

While at a mine in Arizona two years
ago I altered the furnace of a return-
tubular boiler in accordance with a plan
described in Power some 2i_. years ago.

I sealed the grates with mortar three-
quarters of the way back, then laid pieces
of light track rail over them as a support
for a fiooring of firebrick. This in turn
was plastered with fireclay from the
bridgewall forward, leaving the opening
at the front.

Two other plans were tried on this
furnace while I was there, but this one
gave the best results as to fuel econ-
omy and ease of handling the fire. We
used the Wilgus burner.

I do not remember the quantity of oil
burned per horsepower-hour.

Robert Lapsly.

Ohio, Colo.

In answer to D. A. Steiner's question
in the November 7 issue regarding an
approved method of burning fuel oil, I
would suggest the following, which is in
use where I Am employed and is giving
good results:

The gratebars are removed and the
firebox lined with one layer of firebrick.
The bridgewall projects about 6 inches
toward the front. The firedoors and ash-
pit doors are built in with firebrick, form-
ing a lattice work. The burner throws
the oil in at an angle to th^e bottom of
the ashpit. There are about 75 loose
firebrick on the bottom of ashpit where
the oil strikes and ignites. One cannot
burn fuel oil economically with the ash-
pit doors entirely closed where steam
is used for atomization. I operate with

the ashpit doors open about two inches
and the damper about two-thirds closed,
and we get satisfactory results. I could
not tell the amount of oil burned per
kilowatt-hour as we have an ice ma-
chine taking steam from the same boil-
ers. We used 4] 2 tons of good coal in
24 hours when using coal and now we
use about 570 gallons of fuel oil; I think
this is a good showing.

Andrew Blair, Jr.
Norborne, Mo.

Graft

It is a good thing for engineers of
experience to caution the beginners and
advise the owners of the pitfalls en-
countered by the men shouldering the
responsibility. To show how some fall
without any opportunity of self-defense,
how various schemes are devised to
make a market for useless articles and
how the dishonesty of a few has thrown
discredit on many, I will relate the fol-
lowing incident which came within my
own experience:

When I received my first position as
chief engineer a friend congratulated me,
saying: "The salarj' may not be the
best, but the graft is fine." At first I
did not comprehend his full meaning,
but after being in my new position about
three weeks the owners requested me to
test out a new apparatus which had
been installed on trial. The sales agent
for the apparatus gave me some fatherly
advice and told how important it was
that I report it favorably.

The machine worked fine and I was
inclined to believe everything was as
represented, but that night I found a
hundred-dollar note in my vest pocket.
Then the question arose, "How did it get
there?" Naturally I remembered that the
agent was the only person who could
have done such a thing. He had also
taken a cigar out of my pocket and asked
me to smoke one of his; then told me
to have a good time.

Well, there had been no witnesses
but I concluded that he certainly must
be a fool to throw away a hundred-dollar
bill if his apparatus was as represented.
Then it occurred to me that this must
be graft, and I resolved to return the
money the following morning and get a
receipt for it. Fourteen days later the
apparatus broke down beyond repair and
the manufacturers had to take the ma-
chine back. One can imagine what would
have happened if the hundred dollars had
been spent in having "a good time."
Another engineer told me that his super-
intendent had purchased one of those
machines but that he could not see any
good in it as it was constantly out of
order. Of course he could not, but I
could, and whenever I see the man I
wonder how he spent his hundred.

Another ease which I know of is a
company manufacturing electrical ap-

December 26, 1911

POWER

971

paratus, which makes a practice of send-
ing in two bills upon filling each order;
one bill covers the actual price and the
other the listed price. The superintend-
ent forwards the latter to the office for
payment and takes the former back to
the electric company and collects the
difference as his commission.

J. H. White.
New York City.

In the November 14 issue, William J.
Massey mentioned engineers' wages,
graft and a kind of advertising in the
selling section of Power.

Power goes on record as being op-
posed to graft in any form, and I believe
most any engineer would kick a salesman
out of his engine room were he to offer
him a rake-off on an order. No honest
salesman will try to bribe an engineer
and the engineer ought to know there is
something wrong with the goods when a
bribe is offered.

Of course, some men will accept and
some will demand a percentage, but he
pays double what he gets back in overtime
work and worry.

As to the class of advertising referred
to, it leads one to suspect that the ad-
vertisers have been guilty of offering
bribes or they would not know so much
about the evil. In the issue of February
8, 1910, the substitutor was called a
mean cuss and was accused of trading
on another's reputation and of imitating
the several articles used. A man should
sweep around his own door before trying
to clean up elsewhere.

I do»not see anything in the advertis-
ing that would insult anyone; on the
other hand, it is really amusing that one
should try to hide his own misdeeds as
an imitator by hurling the charge of
graft at the engineers. Who is the bet-
ter, the grafter or the man who trades on
the other fellow's reputation?

H. B. Adcock.

Newnan, Ga.

Effective Pressure of a Screw

In the November 14 number, G. P. P.
asks for a means of computing the ef-
fective pressure of a screw.

The weight that can be raised by a
screw, when friction is neglected, is es-
timated as follows:

6.38.^2 Pt

P
where

W = Weight raised or force exerted

by the screw;
P = Force applied to the end of

the lever;
p= Pitch;

r= Distance from the axis of the

screw to the point on the lever

where P is applied.

Owing to the friction between the nut

and the screw, the weight that can be

raised is much less than if friction could

be eliminated.

ir =

A formula has been made up from a
long series of experiments by Wilfred
Lewis to find a factor by which to multi-
ply the theoretical load, to find the actual
load raised. This formula is as follows:

E &_

P + d
where

E = Factor by which to multiply the
theoretical load to find the
appro-ximafe load raised ;
p= Pitch in inches;
d — Diameter of screw in inches.
For example, it is required to find the
load that may be raised by a screw jack
having the dimensions given in the ac-
companying sketch:

Dimensions of Scre^t Jack

Making use of the first rule, it is
found that the theoretical load is
6.2832 X 40 X 24

i

■ = 24,127.48 pounds

which could be lifted were it not for fric-
tion.

Using the second rule, the factor in
this example is

^^ = 0.0909

The theoretical load multiplied by this
factor will give the approximate load that
can be raised by a jack of those dimen-
sions and under those conditions.
0.0909 X 24,127.48 = 2193.18 pounds
real load.

Fred L. Wagner.
Chicago, 111.

A Twenty Four llourlvog

C. R. Ward asks for criticisms of his
24-hour log-sheet report, as published in
the November 7 issue. Although the
generator load is light, the boilers are
working at a fair load, 84 per cent, of their
rated capacity.

The 462 boiler horsepower equals 11,-
088 horsepower-hours per day and costs
S66.39, or 0.6 cent per horsepower-
hour, which is very low. Figuring
the probable kilowatt output from
the boiler horsepower if the total
boiler horsepower was used in the fur-
bine, assuming 7.S per cent, of the boiler
horsepower delivered to the busbars, the
cost per kilowatt-hour would be about
1.1 cents.

Of course, this does not include the
fixed charges which if added would keep

the cost at a veo' good figure. His evap-
oration of 1 1 pounds of water per pound
of coal is good, as the water enters the
economizer at 60 degrees so that all the
heat in the steam comes from the coal
fired in the boiler. The percentage of
ash or refuse is a little over 9 per cent.,
which is very good.

Taking everj'thing into consideration,
this is above the average for a 500-
horsepower plant. The central-station
people do not want a live-steam load and
if Mr. Ward can gradually increase his
generator load he need have no fear of
the central-station man; in fact, this is
the type of plant that the central-station
people keep clear of. Let us hear from
more of them.

J. Case.

Hyattsvillc, .Md.

Trouble with Leaking Tubes

In the Nov. 21 issue, Charles Fen-
wick draws attention to the letter of Wil-
liam Beaton in the Sept. 5 issue. I be-
lieve a feed-water pipe should enter the
front head, extend three-parts the length
of the boiler, cross over and drop down
between the sheet and the tubes and in
no case aproach a seam. If the pipe
begins to scale up internally, the boiler
attendant Will quickly know it before
there is any danger, for it will show in
the length of time taken to feed in a
certain height or quantity of water. The
proper procedure is to remove the pipes
inside the boiler at the regular boiler-
cleaning time, clean the scale from them
and connect again. It is a small job to
remove and connect such a feed pipe
after the first installation.

I am a little skeptical as to the cause
given by William Beaton for the cracks
at the rivet holes, having seen many
boilers which have been in use 15 years
and more, with the feed through the
blowoff pipe and nothing serious ever
happened to them. I do not advocate
this method of feeding as there are better
ways just as easy to install.

Probably the boiler sheet was burned
(as he states that it was badly scaled)
or had at least become overheated, thus
cracking the scale and allowing some
water to reach the hot plate; in this
case rapid contraction would do the rest.

William Fcnwick's improved system
for delivering feed water to a boiler is
very old; there are boilers in Toronto
which have practically the same system
and have had for many years. The idea
has been used in boilers which were re-
moved 10 years ago, on account of old
age.

However, there Is no doubt that such
a scale-catching box is an improvement
over a pipe simply extended down through
the tnr ' ■ - -Tiany of them ai^e, and
cnEi;i '" worse than try the

Idea •

James E. Nobi r

Toronto, Onl.

POWER

December 26, 1911

> . -

Cement for Glass Oil Cups
What is a good cement for fastening
glass into oil cups?

L. S. S.
A good cement for this purpose
is made by mixing litharge and glycerin
into a stiff paste. It will resist the ac-
tion of oil and acid and it is insoluble
in water. Another cement can be made
of ylaster of paris and sodium silicate
(water glass).

Safety Valve Rule

Give a rule to determine the weight
required to load a given safety valve.
M. J. B.

First. Measure the diameter of the
valve (if it is not known) and figure its
area (diameter X diameter X 0.7854).

Second. Weigh the valve and its
spindle. If this is impossible, compute
their volume in cubic inches.

Third. Weigh the lever or obtain
its weight from its dimensions.

Fourth. Obtain the position of center
of gravity of the lever by balancing it
over a knife edge or some sharp-cor-
nered article and measuring the distance
from the balancing point to the fulcrum.

Fifth. Measure the distance from the
center of the valve to the fulcrum.

Sixth. Measure the distance from the
fulcrum to the center of the weight.

Then compute the required weight as
follows:

First. Multiply the pressure in pounds
per square inch (at which the valve is
to be set) by the area of the valve in
square inches. Call this quantity No. 1.

Second. Multiply the weight of the
lever in pounds by the distance in inches
of its center of gravity from the fulcrum;
divide the product by the distance in
inches from the center of the valve to
the fulcrum, and add to the quotient the
weight of the valve and spindle in
pounds. Call this quantity No. 2.

Third. Divide the distance in inches
from the center of the valve to the ful-
crum by the distance, also expressed in
inches, from the center of the weight to
the fulcrum: call this quantity No. 3.

Subtract quantity No. 2 from No. 1
and multiply by No. 3, and the product
will be the required weight in pounds.

Current Consumption of Electric
Heaters
If an electric heater requires 10 min-
utes to bring its temperature up to maxi-
mum and is kept in circuit for 10 minutes

Questions are^

not answered unless

accompanied by the^

name and address of the

inquirer. This page is

for you when stuck-

use it

longer, which period would consume the
most energy?

A. L. F.
As the resistance of the wire increases
as its temperature rises, it will consume
less energy during the second 10 minutes
because the resistance is higher.

Contents of Tank

How much oil is contained in a tank
8 feet in diameter and 20 feet long when
the level of the oil is 23 inches from
the bottom, the tank lying horizontally?
How is it computed?

T. P. M.

Divide the rise or hight of the segment
of the head covered by the oil (23 in
this case) by the diameter, 23 -f- 96 =
0.24.

In a table of "Areas of Circular Seg-
ments," such as are to be found in any
of the better class of engineers' refer-
ence books, find the area correspondina
to this quotient. That corresponding to
0.24 is given in the table as 0.14494.
Multiply this by the square of the diam-
eter and the product will be the area of
the segment.
96 X 96 X 0.14494 = 1335.8 square

inches
This is the cross-section of the body of
oil, which is 25 feet, or

12 X 25 = 300 inches
long. Its cubic contents would be
300 X 1335.8 = 400,740 cubic inches
or, since there are 231 cubic inches in a
gallon,

400,740 ~ 1734.8 gallons

Crank Case Compression

What is the object of compressing in
the crank case of a gasolene engine
working on the two-stroke cycle and how
high should the compression pressure
be?

J. A. McC.

The charge must be compressed either
in the crank case or in a separate pump
cylinder in order to force it into the en-
gine cylinder when the port is opened.

Read the article on "Gas Engine Cycles,"
page 404, of Power for September 12,
1911. The crank-case compression pres-
sure is usually 5 to 8 pounds per square
inch above the atmosphere.

Frequency^ Voltage and Speed

What are the relations between the
frequency and voltage of the supply cir-
cuit and the speed of an induction motor?
B. B. H.

The no-load speed, in revolutions per
second, is equal to the frequency divided
by one-half the number of magnetic poles
per phase in the stator. With a load the
speed drops somewhat, like that of a di-
rect-current motor.

The voltage does not affect the speed
unless it falls so low that the torque
(which varies with the square of the volt-
age) is not sufficient to overcome the
"pull" of the load. At this point, the
motor "breaks down" and comes to stand-
still.

Feed Water Entrance to Man-
tling Boilers

Why does not the feed-water pipe in
the Manning boiler enter the water leg?
A. L. K.

The feed water enters the Manning
boilers as it should all vertical boilers,
well up toward the top to give the dis-
solved air in the water a short path to the
steam space, where it cannot do harm by
hastening corrosion.

Engine Compression
Is it necessary to change the exhaust
valves on a Corliss engine when making
a change from noncondensing to con-
densing?

P. C.
The pressure to which an engine com-
presses depends upon the pressure at
the time the exhaust valve closes. If
the valve is closed with a back pressure
of 15 lb. absolute, that is, running the
engine noncondensing, and that 15 lb.
is compressed into one-quarter of the
volume which the piston inclosed when
the exhaust valve closed, there will be
an absolute pressure of 60 lb. If with
the exhaust valve closing at the same
point there were an absolute pressure
of only 2 lb. in the cylinder, there will
be an absolute pressur- of only S lb.,
and the compression line would not run
up to the atmospheric. If there is con-
siderable compression with the con-
densing engine, it will be excessive when
the engine is run noncondensing.

December 26, 1911

POWER

973

What Means the Dome?

By a. G. Knight

Out in the woods of a certain Southern
State there stands a little narrow-gage
logging locomotive. It has evidently been
deserted for some time as the vines and
shrubs are doing their best to conceal it.

It is not an unusual sight to see these
diminutive '"log-pushers" braving the ele-
ments, trying their best to hold them-
selves together after their work has been
accomplished and the lumbermen have
pulled up stakes for other fields. But
if one looks closely at the illustration he
will quickly discover, just back of the
stack, a dome-shaped structure that is
most unusual to the conventional logging-
camp locomotive.

of the National Association of Cotton
Manufacturers will be held during two
days, and the Master Mechanics' As-
sociation of America will hold its con-
vention, educational meetings and a gen-
eral mass meeting of master mechanics.

Personal invitations will be sent to
10,000 chief engineers, master mechanics,
consulting engineers and others directly
connected in the installing, buying and
specifying of power-producing materials.

The power show gives manufacturers
and dealers an excellent opportunity to
show their products.

About 80 spaces are for sale, and
preference in allotment of spaces will be
given to firms represented in the mem-
bership of the New England Association
of Commercial Engineers.

■ ' -Mr. el| • I.JI

I^^^^^^^^^^^^^^^^^^BK^-^ . '"^ "F

m

ryy^ • .-- . ^in^

Southern Logging Locomotive

Some of the old-timers in the environs
of the little "pusher" were asked to ex-
plain the purpose of this dome. While
they were considerably surprised that
"an engineer from the No'th could not
tell right quick what the ornery thing was
put to," they were obliged to admit that
"we'uns, suh, ain't nevah seen its like
befo'. We kain't tell you-all nuthin'
'bout this yere ingine."

Perhaps some reader of Power has
seen such a dome on a locomotive and
will explain its purpose?

Power Show at Bo.ston

In conjunction with the textile exhibi-
tion, to be held in Boston at the Me-
chanics Building from Apr. 22 to 27 by
the Textile Exhibitors' Association, a
power show will be given under the
auspices of the New England Associa-
tion of Commercial Engineers.

The power exhibition will include the
exhibition of all kinds of power-produc-
ing and transmitting machinery, acces-
sories and supplies. During the same
week the national exhibition of textile
machinery and mill supplies will be held
under the auspices of the Textile Ex-
hibitors' Association; also the convention

I. O. E. Bulletin Binders

A durable binder, suitable for preserv-
ing the headquarters bulletin of the In-
stitute of Operating Engineers and sim-
ilar publications, may be secured upon
application at the offices of the Institute,
29 West Thirty-ninth street, New York
City.

The price is 55 cents, postpaid. For
45 cents additional, the member's name
and the name of the Institute will be
stamped thereon in gold letters.

Chicago Enjrineers' New
Home

Located at 314 South Federal St., the
new clubhouse of the Chicago Engi-
neers' Club is most convenient of access.
The building, of which the club has a
99-year lease, occupies a lot 25x100 ft.,
and when remodeled it will be seven
stories high, of brick and mill construc-
tion.

In leasing the first three floors to a
grill company, satisfactory arrangements
were made whereby the club will be
served with excellent meals on its own
premises at satisfactory prices.

The fourth floor has coat and toilet
rooms, a reception and lounging room,
with a large open flreplace; and a card

room. The fifth floor will ultimately be
used for billiard and club rooms. The
sixth and seventh floors are to be sub-
divided into bed rooms, seven bed and
bath rooms on each floor. In the base-
ment is located the heating plant.

Good taste has been displayed in the
selection of the decorations and furnish-
ings. It is expected that the new in-
vestment will give a comfortable surplus
within a decade.

N. E. L. A. Has Over
10,000 Members

At the meeting of the executive com-
mittee of the National Electric Light As-
sociation, on Dec. 7, it was announced
that the membership had that day reached
10,000 and was, in fact, very nearly
10,150. Up to July, 1909, the member-
ship of the association was still below
3000, but the last two years have been
periods of unprecedented expansion and
there are many indications that the end
is by no means yet, as the present growth
is equal to anything experienced in the
history of the association. The work of
the association is broadening out in every
direction, and the official headquarters
in the Engineering Societies Building are
undergoing equal expansion, four addi-
tional rooms having been taken within
the past three months, so that the space
now occupied is virtually as great as that
occupied by any one of the three founder
societies.

SOCIETY NOTES

The Institute of Operating Engineers
has been unable to fill five vacancies,
ranging in salaries from S1800 to S2600
a year, because of its inability to find
suitable men to fill them.

The annual meeting of the American
Society of Heating and Ventilating En-
gineers will occur at the Engineering So-
cieties building, 29 West Thirty-ninth
street. New York City, on January 23,
24 and 25, 1912.

The ten combined associations of Man-
hattan and Bronx of the National As-
sociation of Stationary' Engineers will
hold their annual entertainment and re-
ception at Terrace Garden, New York,
Saturday evening, December 30.

The Combined Associations of Engi-
neers of Brooklyn at their annual meet-
ing elected the following officers; Past
chaimian. William Smith; chairman.
George Roff; vice chairman, Charles
Schwabacker; corresponding secretary.
Walter Brundagc; financial *ccrciar>',
Charles Eingrcn: treasurer, George O.

K„|r. . ........>, ., .r.,v, Inrnr* Slarrctl.

The ' uprise the

fn|]n il Associa-

tion of Mali»i:,ii> LiiKintLrs Nos. H. 27,
41 and 57, Brooklyn Councils Nos. 8 and

974

POWER

December 26, 191 1

9, U. C. C. of E., Modem Science Club.
The annual entertainment and reception
will be held at Kismet Temple, Febniary
21.

PERSONAL

S. B. Redfield, formerly associate
editor on the staff of the American Ma-
chinist, has accepted a position with
the Ingersoll-Rand Co., and will act in
the capacity of engineer of tests at its
Phillipsburg, N. J., plant. Mr. Redfield
was connected with the engineering de-
partment of the Ingersoll-Rand Co. prior
to his editorial experience.

G. Tisell, of the editorial staff of the
Electrical World, has been appointed
secretary of the Captain John Ericsson
Memorial Society of Swedish Engineers.
The objects of the society are to honor
the memory of John Ericsson and to
promote the interests of Swedish engi-
neers. The society, which now has about
150 members, is actively engaged in col-
lecting articles of all kinds which in any
way relate to John Ericsson's work.

NEW PUBLICATIONS

Power. By Prof. Charles E. Lucke.
Published by the Columbia Uni-
versity Press, New York, 191 1. Size,
5x7;.' inches; 316 pages; 223 illus-
trations; cloth. Price, S2 net.
The book is compiled from a set of
lectures by the author, tracing the de-
velopment in power machinery within the
past hundred years, and pointing out the
enormous strides that have been made
within the last few years. The effect of
this development upon the organization
of society and the conditions of living
is shown, with special reference to the
substitution of power for manual labor
in manufacturing industries and the im-
proved methods of transportation and
communication.

Special chapters are devoted to fuels,
water-power systems, efficiency in steam-
power and gas-power systems. In con-
nection with the latter subject it may be
mentioned that much of the material has
been taken from Cecil P. Poole's "The
Gas Engine," for which the author has
neglected to give credit.

The text combines the historical with a
general view of the present status of
power development. It is written in popu-
lar style and should prove interesting not
only to the engineer but to those outside
the profession.

ment is one of the results of the great
expansion that has been and still is tak-
ing place in the manufacturing world.
It is the science of "making two blades
of grass grow where one grew before,"
of making two carpet tacks or two loco-
motives for what it formerly cost to make
one. In short, it is the science of making
the best use of material, effort and money.

Being a new science, much has been
written and uttered about it that is use-
less and misleading, tending to exag-
gerate the true value of its application in
certain directions. The present book,
however, is dignified and moderate. The
author does not presume to pronounce
the last word on any phase of the broad
subject of which he writes. His aim is
to lend the reader a true perspective of
the entire field.

To anyone who desires to gain an idea
of the field of application and the pos-
sibilities of scientific management the
book is well worth the reading. The
chapters on the various wage systems
and the management of labor are by far
the most interesting.

Principles of Lndlstrial Engineering.
By Charles Buxton Going. Pub-
lished by McGraw-Hill Book Com-
pany, New York, 1911. Cloth; 174
pages, 6x9 inches. Price, S2 net.
Industrial engineering or efficiency en-
gineering, as it is popularly called, is
one of the newest sciences. Its develop-

Hydraulic Turbines: Their Design and
Installation. By Viktor Gelpke
and A. H. Van Cleve. Published by
the McGraw-Hill Book Company,
New York, 1911. Cloth; 293 pages,
7x9 inches; 200 illustrations. Price,
$4 net.
In view of the fact that it has been
within only the last score of years that
water power has been recognized as one
of the world's most important resources
and developed to any extensive degree,
it is not surprising that there is a dearth
of literature in English on the subject.
The present book seems to fill a genuine
need, covering, as it does, the entire
subject of the mathematical design of
both water turbines and impulse wheels.
The book is divided into three sections.
The first is entitled, "Turbines and Their
Accessories." It deals with such subjects
as the designs of and materials for pres-
sure pipes, draft tubes, valves, gates,
racks, etc. The final chapter of the sec-
tion deals with the general design of the
various forms of water turbine together
with speed and pressure regulators. Some
portions of this first section are funda-
mental and for that reason should be
valuable to the student and general en-
gineering practitioner.

The mathematical design of turbines
of all types is contained in the second
section. Several numerical examples have
been completely worked out to illustrate
the various steps in the design and the
use of the proper formula.

The last section of the book contains
the description and illustration of several
representative water-power plants in
America. The plants described have been
selected with the idea of showing the
various forms of development.

Practical Thermodynamics. By Forrest
E. Cardullo. Published by the Mc-
Graw-Hill Book Company, New
York, 1911. Pages, 411; illustrations,
224; size, 6x9 inches; cloth. Price,
S3.50 net.

In the preparation of this book the
author has held to a physical rather than
an abstract treatment of the subject and
has introduced a minimum of higher
mathematics. In the latter connection
such mathematical formulas as are used,
are developed in a logical manner. All
definitions are stated as simply as pos-
sible, and in all, except plainly obvious
cases, are illustrated by concrete applica-
tions.

Although intended primarily as a text-
book for use in technical schools, it is
not dependent for its proper understand-
ing upon supplementary work in the
class room. Hence, it should serve as a
handy reference book for the practising
engineer. The text is somewhat ampli-
fied by a set of problems with answers at
the end of each chapter.

The subject of entropy is treated in
a separate chapter upon which no other
part of the book is dependent. The ma-
terial in this chapter, however, is ar-
ranged so that it parallels the remainder
of the book; hence, this method of an-
alysis may be applied wherever desired.

Chapters are given describing and il-
lustrating the various apparatus that goes
to make up the equipment of the modern
power plant. In this respect it is to be
regretted that more space was not de-
voted to the treatment of the steam tur-
bine.

Considered as a whole, however, the
book is instructive and well written.

BOOKS RECEIVED

Physical and Chemical Constants. By
C. W. C. Kaye and T. H. Laby.
Longmans, Green & Co., New York.
Cloth; 153 pages, 6'Sx9M in.; in-
dexed. Price. S1.50.

The "Mechanical World" Electrical
Pocket Book for 1912. Emmott &
Co., Ltd., Manchester, Eng. Cloth;
3i4x6 in.; illustrated; tables; in-
dexed. Price, sixpence.

Elementary Applied -Mechanics. By
Arthur Morley and William Inchley.
Longmans, Green & Co., New York.
Cloth; 382 pages, 45^x7'/> in.; 261
illustrations; tables; indexed.

Ther.modynamics of the Steam Tur-
bine. By Prof. Cecil H. Peabody.
John Wiley & Sons, New York.
Cloth; 282 pages, 534x9 inches; 103
illustrations; indexed. Price, S3.

The Testing of Motive Power Engines.
By R. Royds. Longmans, Green & Co.,
New York. Cloth: 396 pages. 5';X
8-?4 inches; 193 illustrations; con-
version tables; indexed. Price, S3.

■^^y^iii^- -•

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Engin .

Power

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