pa1778data.pdf

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