The Republican. [volume] (Oakland, Md.) 1877-current, 1883-02-17
Steel and Cast Steel.

confuse the popular ideas as to what
steel is, and what steel was. The word
itself coniures up ideas of cutting i'm
plements mainly, of metal capable of
being so hardened and tempered as to
cut other metals, rocks and almost all
mineral substances as well as to work
wood and a hundred other soft materials.
And when steel is spoken of as being
used for shafting, for heavy castings, for
plates of which to build up the sides of
ships, for railroad rails and similar pur-
poses, the ordinary and unmechanical
mind is confused, and doubts the econ
omy and the advantage of using the ma
terial for such purposes. Perhaps a
brief description of processes may serve
to made distinction. ....
For the production of cast-steel the
best Swedish iron is used, that known to
the trade as "Danemora iron" being
generally employed, although iron pos
sessing similar properties but from other
localities is largely used. Bars about
three inches wide by five-eights OF an
inch thick are of handy and much
used size. These are packed in alright
chambers with fine charcoal, and so ar
IdHSCd bildJ IlO GMO OdIS lO1Slls anu AiAOo
are kept up from nine to fourteen days
by means of furnaces of anthracite coal
Bituminous coal also has been and is used
with satisfactory results. Test bars may
may be drawn from time to time, until
by the judgment of an experienced
workman the concentration is complete.
This roasting of the iron in combination
with charcoal imparts to the iron a GER
tain degree of carbon as compared with
the other constituents, thai has the effect
to totally change its nature.
When removed from the concentration
furnace the bars are covered with bis
tiers, hence the name "blister steel'' for
steel in this condition. Formerly
within forty years this blister steel was
largely usedby blacksrniths for purposes
for which now only cast-steel is en-
ployed. In the ''relaying'' of axes, for
instance, it was used, the quality of the
steel being greatly improved by repeated
hammerings after heatings.
The bars of blistered steel are very
brittle, and are broken up into pieces of
about one pound weight or less, put into
crucibles OF plumbago, and subjected to
an enormous heat for from two to two
and half hours, and then poured into
cast iron moulds of cylindrical form in
side, the ingot thus cast weighing about
fifty pounds usually, although much
larger ingots are made if the after nature
of the work requires it, or the resultant
product demands. If the top of the in
got, while in fluid state. does not sink
in the center (the molds being placed on
end while the steel is poured), it is evil
dence that the casting is unsound, and
no after relocating and hammering can
rectify the fault, the only remedy being
to break up and remelt the honeYcombed
steel.
The ingots are reheated after being
cast, and subjected to the hammer and
then to the rolls. And in the form of
fiat and round bars, and rods, and plates
this product goes out to the world as cast
steel, the great cutting material.
For the production of the steel used
for building and common mechanical
purposes and for railroads there are sew
eral processes, but they each bring about
a similar result, and except for details
or manipulation and employment of diff
fering means, use the same materials.
In some cases the steel is made from the
ore, but in most from the iron (cast).
The Bessemer process will probably stand
as asuIliciently general type of the prin-
ciple OF converting to enable the read
er to understand the difference between
''Steel and cast steel" In the CONVEX
sion OF iron into common. or Bessemer
steel, the iron used is pig, or cast iron,
and not wrought iron in bars. This
iron is selected for the quality of its ore,
and so mixed as to aid in the process of
conversion and to produce satisfactory
results. These particulars are unneees-
sary for the purposes of this article.
The iron is melted in a cupola just as
it is in any iron foundry, and when
melted is run into an immense pear
shaped or ptcher-shaped vessel sus-
pended on hollow trunnions, through
which powerful blast of compressed
air is driven by means of blowing cylin-
ders at pressure varying from fifteen
to twenty-five pounds per square inch.
This pressure is varied during the proc
ess, which for seven tons of melted
iron would require fifteen or twenty
minutes. This blast of air rushes through
the boiling metal, burning out the phos-
phorous and sulphur. and portion of
the carbon, usually about ten per cent.
This loss of carbon is made up by the
addition of certain amount OF SpieqeE-
etsen to the ingredients. "Spiegeleisen"
mirror iron'' is an iron containing an
unusual amount of carbon.
The converters are made of thick boiler
iron, and lined with cement OF ground
flint and quartz, fire clay not being suf-
fcient to withstand the intense heat
generated by the union of the oxygen of
the blast with the sulphur, phosphorus
and carbon of the metal. The end of the
converting process is determined by the
color of the flame rushing from the top
of the converter At first, when the
blast is put on, it is blue and smoky,
afterward red, then graduating to yellow,
and at last to pure white.
When the process is completed the
blast of air is shut off, the immense
pitcher is turned on it's trunnions, its
contents poured into large ladies; which
empty into iron moulds, casting huge
ingots, sometimes of a weight Of 3, 600
pounds. The after working of this Bes-
semer steel is similar to that of cast-steel,
reduction by hammer and rolls.
1t will be seen from these general de-
scriptions that the production of "de-