pa1778data.pdf

U.S. STEEL DUQUESNE WORKS
HAER No. PA-115
(Page 149)
industry wide design and technological advances. 4 While
maintaining the basic principle of the Neeland process, the
reconstruction improved furnace production by providing for the
removal of fine coke breeze from the system, increasing the speed
of materials handling, adding capacity to the hoist bucket,
enhancing the distribution of iron ore within the hoist bucket,
and by utilizing more efficient hoisting facilities. As a
result, furnace capacity was increased from approximately 600
tons of pig iron per day to 900 tons per day.
Coke bins were removed from the eastern wall of the
stockhouse and a double hopper bin, hung from the steel framework
of the reconstructed coke track on the trestle, was installed
directly over each of the newly constructed hoist bucket pits.
The opening at each hopper, located above and to the north or
south of the hoist bucket pit walls, led the coke directly over a
8'-ll 5/8" x 8»-3 13/16" inclined screen which was used to
separate out coke dust or breeze. The breeze dropped through the
screens into a hopper which led to a chute delivering it to the
coke breeze conveyor. Each conveyor, traveling in a northeast or
southwest direction, deposited its contents into one of the two
coke dust bins per furnace located along the eastern wall of the
stockhouse. An electric powered coke dust larry car removed the
breeze when the coke dust bins became full. 5
Materials handling was improved by replacing the hoist
bucket/flat rail car arrangement for delivery to the hoist
carriage with a system made up of hoist bucket pits, direct coke
charging facilities, electrical rail powered scale cars, and a
rearrangement of the bin system. After the coke passed over the
screens, it dropped into a chute which led directly into the
hoist bucket located in the center of each of the newly
constructed pits. The remaining raw material bins (limestone and
iron ore) were reconstructed over the ore yard wall. The bins,
following the "Baker" suspension system, were hung from the steel
framework of the trestle. Their manually operated openings were
located just inside the wall and above a rail track system set
upon the stockhouse floor. The raw materials from the bins were
discharged into a scale car running along the track system by an
operator who pulled down on the handle of the bin opening thereby
allowing the materials to fall into one of two weigh hoppers
attached to the car. After discharge, the car transported the
materials to the western side of the hoist bucket pit where the
weigh hoppers were pneumatically opened and the contents were
emptied into one of two chutes leading to the hoist bucket. 6
The hoist bucket itself was enlarged to 250 cu. ft. full
capacity and was attached by its stem directly to the hoist
carriage. In order to improve the distribution of the charge