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Workmanship.
Linings.

812. Bearings shall be bored for the journal and finished smooth after the lining has been put in. The bearing shall be bored 1/50 inch larger than the diameter of the journal. Bearings for rack pinion shafts shall be bolted to the bracket supporting them and bored while so fastened to insure perfect alinement. The edges of oil grooves and the edges of linings shall be rounded.

Bronze linings shall be turned on the outside to fit the bored hole in the bearing.

Babbitt metal shall be poured in the bearings in such a way that the thickness of the lining after boring will be uniform. Bearings.

813. The rubbing and bearing surfaces and the joints between cap and base of bearings shall be finished. The holes in cap and base shall be drilled. The holes in bearings for bolts. fastening them to their supports shall be drilled st inch larger than the bolts. The holes in the supports shall be reamed to fit after the bearings have been adjusted. Gear Teeth.

814. The teeth of gears transmitting power for the operation of the bridge, bevel gears, and wheels in the gearing of any motor, shall be machine cut. The periphery and ends of teeth of gears shall be turned. The pitch circle shall be scribed on the teeth. Bevel Gears.

815. The teeth of bevel gears shall be cut by a planer having a rectilinear motion in lines through the apex of the cone. Rotating milling cutters shall not be used for making bevel gears. Machine Molding.

816. Uncut teeth shall be machine molded. Worms and Worm Wheels.

817. Threads on worms shall be machine cut and the teeth of worm wheels shall fit the worm accurately with surface or line contact. Keys and Keyways.

818. Keys shall be planed and keyways machine cut. The finish of the keys and keyways shall be such as to give the key a driving fit on the sides. Tapered keys shall bear on the top, bottom and sides; parallel faced keys on the sides only. Castings.

819. Castings shall be cleaned and all fins and other irregularities removed so that they will have clean, smooth surfaces, suitable for this class of work. Castings which are to be attached to structural steel or other castings shall have their contact surfaces finished. Unfinished edges of bases, ribs and similar parts, shall be neatly cast with rounded corners. Inside angles shall have proper fillets. Bosses shall be finished to the corroct plane.

Workmanship-Erection.
Bolt Holes and Turned Bolts.

820. Holes for unfinished bolts shall be drilled or reamed not more than to inch larger in diameter than the bolt. The diameter of the shank of turned bolts shall be at least to inch larger than the diameter of the threaded portion. The bolt shall be 1/64 inch smaller in diameter than the bolt hole. Assembling Machinery.

821. If practicable, machinery parts shall be assembled on the supporting members in the shop. They shall be aligned and fitted, and holes in the supports shall be drilled with the members in correct relative position. The members shall be match-marked both to the supports and to each other, and re-erected in the same relative positions. If assembling is not practicable, the holes in the supports shall be left blank and drilled in the field after the machinery parts are assembled and aligned. Sheaves.

822. The grooves in sheaves shall be turned. The shape of the grooves shall conform as closely as feasible to the rope section so that while the ropes shall run freely in the grooves, the sides of the grooves shall prevent the wire ropes from flattening under static loads, as when supporting counterweights. Built sheaves shall be assembled and permanently riveted before the grooves are turned. Grooves in Trunnions.

823. The grooves in the surfaces of trunnions and similar large bearings shall be machine cut. Small inequalities may be removed by chipping and filing. The grooves shall be smooth, especially the rounded corners. Holes for Sheaves for Vertical Lift Bridges.

824. In vertical lift bridges, the holes in the girders and columns for the bolts connecting the main sheave bearings to their supporting girders, shall be drilled from the solid through cast iron or steel templates on which the bearings were set and accurately aligned when the holes in the bearings were bored. The bolt holes and the bolts shall be turned to the same diameter and the bolts driven to place without injury to them, the bearings, the girders, or the columns.

Air Buffers.

825.

The workmanship on air buffers shall be so accurate that the weight of the cylinder and its attachments will be sustained by the confined air for six minutes, with a piston travel not more than that which

occurs during the closure of the bridge. The valves must be closed and

so that the whole weight is carried by the piston rod.

the buffers balanced

(9) ERECTION The General Specifications for the Erection of Steel Railway

the American Railway Engineering Association shall apply to the erection of movable bridges, with additions specified herein.

901. Bridges of

Erection.

Protection of Parts.

902. Parts which are protected from the weather in the finished structure shall be protected in the field during erection by housing or equivalent means. This applies in particular to electrical parts.

903. Rubbing surfaces of trunnions and machinery bearings shall be protected by metal thimbles packed with oil-soaked waste.

904. Wire ropes shall be housed and stored at least 18 inches above the ground. The ropes shall be kept free from dirt, cinders, and sand. During erection, the ropes shall not be pulled through dirt, or bent into sharp angles or kinks. Lubrication,

905. The counterweight ropes and the operating ropes shall be given two coats of dressing, with an interval of one month between the coats. The dressing shall not be applied in an atmospheric temperature below 40 degrees F. The Contractor, during erection, in particular just before the final test, shall lubricate the sliding parts and fill all grease cups. Channel Lights.

906. During erection and in taking down the old span, the Contractor shall place and maintain navigation lights and signals, in accordance with the government requirements, for the protection of the falsework, as well as navigation. Erection of Machinery.

907. The machinery shall be erected by men skilled in the work. Special care shall be given to the alinement of trunnion bearings. Testing of Machinery.

908. Before the main operating machinery is connected for transmitting power, it shall be given an idle run of 8 hours.

909. The end lifting devices shall be adjusted to produce a lift equal to the deflection caused by the negative end reaction of the live load and impact plus 25 per cent. of their sum.

910. The Contractor shall adjust the counterweight so that the span will be properly balanced. Bridge Operator.

911. For a power operated bridge, the Contractor shall provide at his own expense, a competent man to supervise the operation of the bridge for a period of 30 days after acceptance. The man shall instruct the employees of the Company in the operation of the bridge.

Articles

Articles
Acceleration
..105 Buffers, air

404, 825
Air brakes

606, 639
Built sheaves

.447
Air buffers
404. 825 Bushings

209
Air compressors

607, 639
Air piping

639
Cables

.618, 664
Air tanks

.607, 639
Cams

435
Alining and locking mechanism. . 203

Castings, workmanship

819
Alternating current motors..619, 628

Cast iron

209, 312
Alternating motion

.314
Cast iron bearings.

209, 422
American Institute of Elec-

Cast iron in electrical parts. 656
trical Engineers, Standardi-

Cast Steel

209, 312, 701
zation Rules

.617, 628

Center bearing bridges... 211, 411, 413
American Society of Mechanical

Center castings

805
Engineers, Boiler Code.

610
Centering devices

403
Ammeter

615
Center panel shear.

214
Assembling

..806, 807, 821
Center of gravity.

. 106
Assembly drawing of machinery..104

Center pivots

..412
Automatic circuit breaker.... 647, 653

Centers, assembling

.806, 807
Automatic control

.605, 637
Center, type of.

.210
Automatic cut-off

643
Center truss panel.

214
Automatic stops

643
Center wedges

305, 426
Auxiliary power

204
Channel lights

109, 906
Check nuts

419
Babbitt metal.

209, 717, 812 Chemical requirements of metals
Back geared motors.

630

701, 702, 709, 714, 717
Balance wheels
413, 804 Circuit breakers

644, 647, 653
Balancing chains
113, 202, 209 Circuits

622. 641, 659, 667
Ball bearings
209 Classification for payment.

.112
Bars, reinforcing

113
Classification of parts.

. 112
Bascule bridge
308, 606 Coal bin

.613
Bearing points on rim girders. 212 Coal hoist

.613
Bearing pressures
313-315 Codes and rules.

101, 610, 617
Bearings:

418-423 Coefficients:
Cast iron
209,422 Braking

311
Clearance
122. 812 Friction

309
Dust covers

425
Machinery losses

310
Finish
812, 813 Machinery resistances

309
Grooves
424, 812, 823 Wire rope friction.

444
Lining
209, 422, 812 Cold rolled shafts..

209. 426
Line shafts

209
Collar friction

309
Location

418
Collars

.314, 427, 435
Lubrication
424 Collector rings

662
Reaming of holes and supports Combined bearings

212, 213
419, 813 Common return wire,

.667
Step

429

Company:
Templates

824 Specifies time of opening. 103
Workmanship

812, 813 Furnishes and installs railway
Bending stress in wire ropes..317, 318 signal system

108
Bends in conduits.

659 Furnishes deck and track ma-
Belal gears.,
.310, 428, 431, 432. 815
terial

.113
Boiler code

610 Stipulates kind of power. .601
Boiler feed pump..
613 Furnishes lamps

.666
Boilers
610. 611 Compressed air

426
Boilers and tanks
112, 113 Compressor, air

.113, 607, 689
Bolt heads

441 Concrete

113, 406, 409
Rolt holes
820, 824 Conductors, rolled steel.

.663
Bolts, turned. 209, 419, 820, 824 Conduits

622, 659, 660
Boxes
.655, 659 ('onnecting rods

209
Bracket for main pinion bearings.423 Contact areas

650, 663
Brake housing
642 Contactors

636, 637
Brakes,
.311, 606, 638-641, 643 Contacts

637, 647, 654, 663
Braking capacity

311 Contractor:
Braking, dynamic

627 Responsible for complete instal-
Braking stresses

311

lation of superstructure.. 102
Bridge locks, mechanism.

203 Furnishes

erects struc-
Bridge operator

911

tures ready for application of
Bridge rail ends,

401
power

102
Brinell ball test.

711 Furnishes outline drawing of
Bronze

209, 312

machinery, assembly drawing
Bronzes

710-716

and detail drawings......102, 104

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and

Articles
Specifications

..617
Tests

.620, 624, 627, 628
Working plans

622
Emergency brake. ...606, 640, 641
Emergency switches

648
End bearings

305
End floorbeams

302
End lift:

405
Machinery .203, 305, 321, 405, 426
Reactions

305
End shoes

209
End ties

303
Engine room appliances.

613
Engine room equipment.

613
Engineer determines type

of
bridge

. 201
Engines:
Definition

.113
Gasoline

614-616
Rating

604
Steam
Equalizing devices

.434
Equalizing levers

449, 513
Erection

901-911
Excess loads

.320
Extra parts

616, 631

...608

Contractor:

Articles
Furnishes torque curves.. ...105
Computes location of center of
gravity

.106
Furnishes and builds machin-
ery house

107
Furnishes and installs devices

for interlocking bridge ma-
chinery

108
Furnishes and installs warning
lights

109
Furnishes wrenches

.110
Remedies defects

.111
Furnishes air piping system....607
Furnishes spare parts..

..631
Places lamps in sockets.

666
Control, automatic and remote..

..636, 637
Control of motors

636
Controller equipment

.637, 641
Controllers

.632-634
Countershafts

630
Counterweight, amount

.202
Counterweight ropes. 316, 317, 407, 445
Counterweights:
Access to

208
Adjustable

406
Balancing

202, 910
Center of gravity.

..106
Divided

.407
Frame

406, 408
Metal in

113
Pockets in

.408
Concrete in

.409
Couplings...

.209, 430, 614, 810
Covering pipes

612
Covers:
Dust and gear.

425
Metal

655
Sheave rim

425
Crane, traveling

207
Crane hooks

209
Crane type motors

619
Crank pins

314
Crank material

209
Cross-head slides, bearing pres.
sure

313
Cut-offs

643
Cycle

604
Cylinders

.113, 209, 639
Deck

113
Defects

.111
Definition of classes.

.113
Details of design..

401-449
Diameter of sheaves.

.410
Direct current motors. 619, 627, 637
Disc bearings

411, 413
Disc center assembled.

806
Discs...209, 309, 411, 412, 424, 713, 806
Drain holes

418
Drawings of machinery.

104
Drums, attachments of ropes.. 444
Duplication of machinery parts...104
Dust covers

.425
Dynamic braking

627
Eccentrics

209
Efficiency of gearing.

310
Electric horn

607
Electric lighting

.666
Electric power equipment. 617-667
Electrical control

605
Electrical equipment:

113, 617
Design of

436, 621
Protection

.629, 902
Size of parts. .622, 649, 650, 653, 657

Feed pump

613
Fillets in shafts, trunnions and
journals

.808, 809
Flexible connections

660
Floor surface

307
Fly wheels

209
Foot brakes

606
Forged steel:

702-708
Annealing

706
Chemical requirements

.102
Physical qualities

..703
Test pieces

.703, 704, 708
Tests

704, 707
Unit stresses

.312
Used

209, 513
Forgings

702-708
Friction:
Clutches

608, 614
Coefficients

.309, 311
Journal

310
Moving

.309
Rollers

209, 309
On guides

309
Sliding

.309
Starting

309
Wire rope

309, 444
Fuel tank

.614
Fuses

.644, 647, 653, 667

Gasoline engines

614-616
Gear case

.630
Gear covers

.425, 630
Gears:
Bevel

.431, 432, 815
Eficiency of

.310
Equalizing

.434
Material

209, 630
Motor

630, 631
Pitch circle

431, 814
Worm

209, 435
Gear teeth:

431
Cut

.433
Cutting of, in bevel gears. .815
Dimensions

431
Forces acting

104. 432
Machine molded

.432, 816
Pitch

431
Strength of

432
Type

431

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