The Anaconda standard. [volume] (Anaconda, Mont.) 1889-1970, 1896-02-10
IMPROVED METAL WORKING.
Recent Inventions Are Simplifying the
Processes Hitherto In Use.
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Recent Inventions Are Simplifying the
Proccss,s Hitherto In Use.
From the Baltimore Sun.
A most important invention in metal
working is the Erhardt process for the
production Of tubular bodies by thrust
ing a steel core by hydraulic pressure
into a hot mass of metal. The pro-
cess has been patented in Europe and
America and for two years past has
been in highly successful operation in
the works Of the Rhenish Metal Ware
company at Dusseldorf According to
the description of the invention and it's
pratical results in consular reports No.
1873, for December, it promises to revo-
lutionize the manufacture of gun bar
rels, hollow projectiles, acid TASKS and,
generally, all tubular forms, within
certain limits Of size. which must COM
bine liEhtness with strength. The
principle may not be wholly new. In
england an analogous method has
been employed on a limited scale, but
the German machines and methods go
so far toward perfecting its applica-
ton THAI II must be conceded TO be
a new departure.
At Dusseldorf the shrapnel shells for
the German field artillery are made
by the Erhardt process. There Is pro-
vided q nIatriX which Is to form the
exterior of the she'll Into this matriX
a piece of steel rod three inches in di-
ameter and about 10 inches long, heat
ed to a cherry red. is dropped. Then
by means OF a hydraulic press a solid
steel core. or mandrel. is pushed into
the red-hot steel With one noiseless
thrust IL penetrates the hot steel like
so much wax, spreads the plastic met
al out evenly and shoves the end Of il
into the bottom of the matriX, where
il is tapered to a point. The exterior
of the shell is conformed perfectly to
the shape of the matIix; the interior
to the shape OF the core. The process
requires but two seconds. An advan-
tage much in its favor is its economy.
In the manufacture of some articles
there is a saving OF as much as so per
cent. At the same time there is a de-
cided superiority OF quality Shells,
gun barrels, cannon. boiler tubes and
bicycle frame tubing thus made are of
homogeneous internal structure, and
vastly stronger than when made by
other methods.
In the making Of a gun barrel, for
example, the solid heated metal being
driven by lateral displacement into it's
new form by n steady resistless pow
or. Is compressed in a high degree.
Every flaw is obliterated, and the in
strongest So great is the pressure
tha. when the mandrcl or core Is with
drawn the surface il leaves has a glis-
tcninC appearance. as If polished by
friction. Flasks for liquid carbonic
acid are made four or five feet long
by eight in diameter. being shaped by
a single movement. such is their quail
ity. being without seam or flaw. that
they readily sustain a pressure Of $50
atmos phercs. Steel cannon tubes Of
SiN-inch calihers and over are thus
made. and the government requires all
makers Of guns and proiectilCs for
army and navy 10 use the Erhardt
process. other metals arc used i'm like
manner, care being taken to subject
each to such conditions of tempera-
ture etc. as us special qualities re-
quire. Copper tubes are made Of all
ordinary sizes and of lengths up TO 20
feet. There seems to I've no limit to
the application of the Erhardt process
as respects diameter, length and she'll
thickness OF the hollow body produced,
except i'm such as is fixed by The size
Of the machinery and the degree Of
force employed Any mallcable metal
may be worked and a a saving in
comparison with the methods hitherto
in use.