pa1778data.pdf

U.S. STEEL DUQUESNE WORKS
HAER NO. PA-115
(Page 12 0)
of a front and rear 30" diameter rail wheel and axle assembly
from which the carriage's steel framed platform is hung. The
distance between front and rear wheels is 28'-0". The platform
is 9'-6" wide x 37'-9" long x 2'-0" deep. Along the centerline
of the platform, located approximately 7 , -0" from its west end
and 2 ! -6" from its east end are each of the trolley's two Crocker
Wheeler 75 hp travel motors running at 475 rpm with accompanying
Falk gear drives and Cutler Hammer brake assemblies. Set between
the travel motors are two Crocker Wheeler 200 hp hoist motors
running at 380 rpm with their accompanying Falk gear drive and
36" diameter winch drum assemblies. A 1 1/8" diameter rope,
wrapped around each of the winch drums, is connected to a 15-ton
Blaw Knox bucket scoop. The bucket is capable of traveling
horizontally for a distance of 279*-o" at a maximum trolley speed
of 600 feet per minute. The hoisting speed of the motor, drive,
and winch drum assembly is 200 feet per minute.
2. Repair Hoist: The repair hoist for the equipment on the
man trolley is located on a monorail which is riveted to the
underside of the structural steel bracing at the top chords of
the bridge span, 24*-0" above the trolley's platform. Attached
to the monorail, which runs the entire length of the span, is a
Wright-Speedway hoist crane with a capacity of 15,000 pounds.
3. Control House and Operators Cab: A 15'-0" wide x 16'-0"
long x 10'-0" high control house is suspended from the western
end of the trolley carriage. It sits on a platform which is
suspended from the northern and southern side of the trolley
platform. The steel framed sheet steel exterior building houses
electrical switch gear. The 6'-6" wide x 7'-2 M long x 7'-ll"
high sheet steel exterior operator's cab for the man trolley is
hung from the control house about the centerline of the bridge
span. It sits on the eastern edge of a 12 f -6" wide x 14'-0"
platform which is hung from the control house platform.
4. Trolley Walkway: Made of steel grating, the 4 ! -0" wide
walkway is wedged between and welded to the bottom chords of the
bridge span and the trolley rail chords on all four sides of the
structure.
5. Trolley Rail Buffer Assembly: The trolley buffer
assembly consists of a 30" diameter hydraulic cylinder equipped
with a piston rod capable of delivering a 3*-8" stroke which is
mechanically connected to stoppers at each corner of the trolley
runway. Each buffer assembly, which carries an estimated
capacity of 15 gallons of Gulf # 501 oil, is designed to absorb
the shock of the trolley as its reaches the end of its run.
6. Dumper: The dumper is composed of a 50-ton hopper