Mineral Point tribune. (Mineral Point, Wis.) 1869-1938, 1898-10-20
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IRON KNEADED LIKE DOUGH,
Great Castings Squeezed Into Shape by
Hydraulic Power.


One Of the effects Of the present war
has been to arouse public interest in the
great industrial establishments of the
country for the manufacture Of armor
and metal castings used in ship and
engine building.
The Bethlehem Iron company is one
Of the largest and most progressive con-
Germs of this kind in the world, It's ma
chinery is Of the most gigantic proper
tiou, and the work performed is on a
proportional scale. Open hearth steel
ingots are here cast weighing $50, 900
pounds and over. These are lifted by
the great travelling cranes as readily as
though they weighed but few pounds
each, and they are squeezed in the giant
press into huge pancakes as readily as
though made of dough, forged into the
proper shapes and finished in size with
degree of accuracy that is simply
amazing even to those who are familiar
with the work, and incomprehensib bic to
others.
A few years ago this company built
giant steam hammer (the biggest in
the world, the falling part of which
weighed l25 TONS This was intended to
forge all the ingots into shape for shafts
and other purposes, but the increased
size of the forgings soon outstripped the
capacity of even this leviathan ma
chine, and it became necessary to con-
struct much more powerful "squeez-
err" The new IA, 900 ton hydraulic
forging press has entirely superseded
the 1875 ton steam hammer. A pumping
engine of 15 900 horsepower is required
to operate the pumps for moving the
pistons of this huge press when slowly
squeezing an immense ingot of steel. 1t
was found that the blows of the 1875 ton
hammer merely compressed the metal
near the surface of the ingot, and the
central portions remained spongy or
porous in the largest ingots. This was
owing to the suddenness of the blow,
but under the slow motion of the hy-
draulic press time is allowed for the
molecules Of the metal to 'how," and
a uniform texture is produced through
out the section of the forging.
1t may not be incorrect to compare
the method Of working gigantic ingot
of redhot steel to the kneading of a
mass of dough by the baker. All metals
are plastic under sufficient pressure,
acting like rubber or dough, and they
may even be made to flow exactly like
a fluid through an oritioe
In order to get rid Of the gases or air
bubbles that may be entrained or caught
in the ingot while pouring the mold
when filled with molten steel is placed
under an enormous 1000 ton fluid com
preston press and the metal is subject
ed TO squeezing until it becomes per-
fectly solid.
An exceedingly interesting achieve
ment Of these works is the nickel steel
coming tower for the cruiser Brooklyn
It's inside diameter is nearly - feet
its outside diameter is nearly feet
and its length is nearly 10 feet Its
weight when put on the car was 1850
pounds.
Among the earlier successful attempts
to produce hollow forged steel shafts of
large size is the shaft for the great Fer
ris wheel at the Chicago exposition.
This shaft was 40 feet long, nearly 3
feet outside diameter, and it weighed
80, $50 pounds. -Philadelphia Record