pa1778data.pdf

U.S. STEEL DUQUESNE WORKS
HAER No. PA-115
(Page 216}
of 70" with a maximum screw speed of 600" per minute. Product
sizes from the 46" mill included up to 52" wide slabs with a
minimum thickness of 3 1/2", bloom sizes up to 20" square and
various breakdown sizes for subsequent rolling in the 36" mill.
Product sizes down to 8" square could also be finished on the 46"
mill when the 36" mill was rolling smaller sections.
Following the exit end of the remains of the 4 6" mill roll
stand, is a 78*-9" long mill run-out table. This table delivered
the bloom or slab to the 63*-8 M long scarfer delivery table. The
scarfer, manufactured by the Linde Division of the Union Carbide
Corporation, is dismantled. By using a constant supply of air,
fuel gas, and oxygen as cutting agents, it was capable of
"scarfing," or removing surface defects on the bloom or slab at
its edges only, top and bottom only, or on all four sides. An
electrical precipitator, located due east of the scarfer on the
outside eastern wall of the south motor room, cleaned waste gases
from the scarfer.
After passing through the scarfer, the bloom or slab moved
to the 60'-5" long shear approach and entry table. The 46" x
110" mill shear was manufactured by the Mesta Machine Company.
The electrically driven, up-down cut type shear, was powered by
four 500 hp motors. It was capable of shearing blooms or slabs
with a maximum thickness of 22" to a maximum length of 20'-0" and
a minimum length of 6 f -0". Crops from the shear were directed
through scrap chutes into one of two 21-ton skip hoists which are
located in a pit just west of the shear in the scrap and scale
building. The skips eventually dumped the crops into charging
boxes which were transferred to the plant's steelmaking
facilities where the crops were used as revert scrap.
Next in line is the 46" x 110" mill slab piler and transfer.
The outlet for slabs and larger bloom sizes which were finished
on the 46" mill, the elevator type piler was capable of piling to
a maximum height of 3 *. It placed the slabs or blooms on a
transfer car which travelled to the shipping building and were
unloaded by a "C" hook equipped crane. On the north side of the
piler is a pneumatic impact stamping machine. Operated by the
piler-transfer operator, the machine was used to stamp
identifying numbers on each slab or bloom.
Blooms which were slated to be rolled into smaller sizes
passed directly from the 46" x 110" mill shear to the 36" x 78"
2-high reversing blooming mill. Manufactured by the Birdsboro
Company and powered by two 3 000 hp motors, the mill was capable
of producing blooms or billets in square or round shapes ranging
in size from 15" to 4 9/16". Only the housing for the rolls
remains in place. The top roll, when in place, had a maximum