News and citizen. [volume] (Morrisville, Vt. ;) 1881-current, 1883-08-09
MAKING STEEL CANNON.
How Great Gums are Manufactured ut TIT
Washington Navy Yard.

Washington Navy Yard.
The Washington RepUbiicGt says
The two new six inch steel guns now be-
ing constructed III the ordnance shops at
the navy yard will probably not be fin
ished for several months. The work OF
building them is necessarily slow one.
All the labor is performed in the shops
here, except the manufacturing of the
steel. That is done at the Midvale
Works, in Easton, Pa The steel then
is shipped to Washington, and the work
OF converting it into cannon is performed
This is a complex operation, and to the
locker on is decidedly interesting. The
steel is first turned by a lathe working
slowly, but with tremendous power I'M
| til the heavy mass of ''steel in the
rough" so to speak, becomes a long
cylindrico- conoidal column. In this
condition it is placed in proper position
and a hole drilled clear through it by
means of what is called a "hog bit. "
/ This hog bit is a small rectangle of very
hard steel, turned up at one end in such
/ a manner as to form rude vertical sec
| ton of a spherical triangle. The whole
rectangular piece is then clamped down
upon a fiat shaft of chilled iron in such a
manner as to fit in and form one piece
with the shaft The latter has ut the
| opposite end a cylindrical shape, which
end is held in a frame and worked by
appropriate machinery moved by steam
upon one end of the steel column to he
perforated The end of the column is
first "dug into" little, and then the
"hog bit" does its work It revOlves on
its axis and the "bit" describes a circle,
tearing out the hard steel slowly but
surely AS the guns have bore of six
inch diameter, and the bit describes a
circle of only two and three-quarter
inches radius, the enlargement of the
perforadon is accomplished 10y other
bits.
OF steel requires to be 'Jacketed, - col
Jared and ''breeched' before it is al
lowed to graduate into the society of
cannon. The jacket is an outside wrap
of steel, followed in the same way,
heated until it expands sufficient to be
slipped over the tube it is intended to
jacket. Upon cooling this outside wrap
contracts and presses upon the now in
side tube with almost the same degree
of cohesion as the molecules of the steel
themselves. The object of the Jacket"
is to strengthen the gun and prevent
accident. The explosive force of gases
evolved from gunpowder being tremen-
dous and occurring mostly at the breech
the primary object Is to strengthen this
latter part. Collars of steel, great blocks
Of carbonized iron having been turned
into shape and perforated, are next ex-
banded by the heat and slipped over the
breech part of the gun. When con-
tracing they grow into and become
part of it. The breech head of the gun
is next lathed and fashioned, different
wOrkmen being employed on different
parts of this. The rifing of the gun is
another step. A different kind of ''bit'
from the hog" a spur of steel tempered
to great hardness, is clamped to the CEN
tire of a semi-circular piece of copper
and iron, and this last device is slowly
worked through the gun on spiral turn,
giving the rifle twist. The breech
head is then grooved and adjusted and
the breech cap formally adjusted. This,
as IS known TO all who have examined
brcech-loaders, swings back on a hinge
or sE.rIr- and when closed is secu.aly
locked by lever clamp.