pa1778data.pdf
pa1778data.pdf
pa1778data.pdf
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U.S. STEEL DUQUESNE WORKS<br />
HAER No. PA-115<br />
(Page 73)<br />
Although immediately successful, men were still required to dig a<br />
starting point from which the machine unloader could work until,<br />
through a bit of improvisation, a quarter section of a scrap<br />
ingot mold was placed in one end of each car just before casting.<br />
Removal of the section after solidification provided the<br />
necessary starting point for the unloader. The addition of a<br />
make-shift raised platform supported by scrap ingot molds and<br />
straddling the casting car unloading track refined the operation<br />
because it allowed the excavator to unload directly into trucks<br />
or rail cars for shipment on one side of the platform or to a<br />
stockpile on the other side. Eventually a permanent raised<br />
platform was constructed in conjunction with the installation of<br />
a new crushing, screening, and storage system in 1955.<br />
The new system, which capped the modernization of the<br />
plant's ferromanganese facilities, was the result of an extensive<br />
study to identify consumer needs taken on by the company after it<br />
was decided to centralize production at Duquesne. Determination<br />
of a product size suitable for furnace and ladle additions at<br />
consumer facilities was of particular interest. To this end, it<br />
was decided to install a crushing, screening, and storage system<br />
which was interlocked by two sloped conveyors, 50 and 250 feet in<br />
length respectively. Laid out in the shape of an L, the process<br />
began at ground level with the excavator feeding the large chunks<br />
of "ferro" from the casting car to a crusher capable of<br />
processing 125 tons per hour. After crushing, the material was<br />
conveyed to an elevated screening station where it was separated<br />
by size as it passed over three grids of a shaker screen.<br />
Depending upon its size, the material was dropped through a duct<br />
to one of three 150-ton storage bins, each of which was equipped<br />
with a retractable chute for gravity loading onto railroad cars<br />
or trucks. In 1965 a parallel crusher and conveyor was added to<br />
the system along with a ground level storage building constructed<br />
off the side of the car preparation building. 5<br />
During the late 1950s and early 1960s significant changes<br />
were made to the plant's iron production and delivery facilities<br />
beginning with the dismantling of blast furnaces numbers five and<br />
six and their replacement by Dorothy Six. Possessing a working<br />
volume (49,568 cu. ft.) which surpassed the combined working<br />
volume of the two furnaces (49,540 cu. ft.) it replaced, the<br />
108 f -0" high x 28 , -0" hearth diameter furnace also exhibited<br />
notable recording features and casting facilities. A total of<br />
ten probes were placed in an horizontal position at three<br />
different heights along the furnace stack in order to give<br />
furnace operators information about the composition of gases and<br />
temperatures throughout the furnace. The power driven probes<br />
burrowed their way to the middle of the burden before they were<br />
withdrawn. As the probes exited the furnace, they were stopped