The Portland daily press., 1898-07-16
IRON KNEADEo LIKE DOUGH.
Great Castings Squeezed into shape by
Hydraulic Power.
fFrom the Philadelphia Record.)

(F'rom the Philadelphia Record
Ono of the effects of the present war
has been 10 arouse public interest IN the
great Industrial estab lishments 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. Its
machinery is of the most gigantic proper
lions and the work performed is on a pro-
porticnal scale. Open hearth steel ingots
are hero cast weighing 10000 pounds
and over. These are lifted by the q eat
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 incom-
prehensible to others.
A few years ago this company built a
giant steam ha rmer (the biggest in the
world) the falling part of which weighed
1875 tons. This was intended to forge IL
the ingots into shape for shafts and other
purposes, but the increased size of the
forgipgs soon outstripped the capacity of
ever. this leviathan machine, and it be-
came necessary to construct a much more
powerful "squeezer. The new IA, 600 ton
hydraulic forging press has entirely super
seeded The 125-tOn steam hammer. A pump
ing engine of $4,000 horsepower is re-
Quired 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 12o-ton
hammer merely compressed the metal
near the surface OF the ingot and the CEN
trail portions remained spongy or porous in
the largest ingots. This was owing to the
suddenness Of the blow, hut under the
slow motion of the hydraulic press time is
allowed for the molecules of the metal to
''fow," and uniform texture is pro-
duced throughout the section of the forg-
ing.
1t may not be incorrect to compare the
method of working a gigantic ingot of
redhot steel to the kneading of mass OF
dough by the baker. All metals are
plastic under sufficient pressure, acting
I1h0 IuUUSI VI uouSu, uuo oilOy 1hHy OsSA
be made to flow exactly like fluid
through an oritice.
In order to get rid of the gases or air
bubbles that may be entrained or caught
nsthe ingot while pouring, the mould,
when filled with molten steel, is placod
under an enormous 7.O00-ton fluid COM
preston press and the metal is subjected
to squeezing until it becomes perfectly
solid. 81 aB Ana
An excaedino1y interesting achievements
Of these works is the niekel-steel coming
tow for the cruiser Brooklyn. Its inside
diameter is nearly 6 12 feet, it's outside
diameter is nearly 9 feet and It's length Is
nearly 10 feet; its weight when put on the
car was 1880 pounds.
Among the earlier successful attempts
to produce hollow forged steel shafts of
large size.is the shaft for the great Ferris
wheel at the Chicago Exposition. This
shaft was As feet long, nearly 3 feet out
side diameter and it weighed SO, 800
pounds.