IMPROVEMENTS IN CONVERTING CAST IRON INTO WROUGHT IRON, AND IN UNITING OXIDES AND FLUXES WITH MOLTEN CAST IRON
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by Charles Denton Abel at the
Office of the Commissioners of Patents, with his Petition, on the
28th September 1868.-A. communication from abroad by Thomas
Shoenberger Blair, of the City of Pittsburg, Pennsylvania, United
States of America.
I, CHARLES DENTON ABEL, of No. 20, Southampton Buildings,
Chancery Lane, in the County of Middlesex, Patent Agent, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN CONVERTING
CAST IRON INTO WROUGHT IRON, AND IN UNITING OXIDES AND FLUXES WITH
MOLTEN CAST IRON," to be as follows:-
The nature of this Invention consists, first, in a new mode of effecting
a mechanical mixture of solid oxides, fluxes, or other suitable oxidizing
substances with molten iron; second, in treating cast iron in a liquid
state with oxides in a solid condition reduced to lumps, grains, or
powder, so that they can be stirred or mixed in with the iron me-
chanically; and third, in further treating the material thus produced
by subjecting it to the action of heat until it is reduced to homogeneous
wrought iron.

page_text: To enable others skilled in the art to make and use these improvements
I take the
I will proceed to describe their nature and manner of use.
fluid cast iron, whether direct from the blast furnace or remelted, in
any convenient method, and pour it into any suitable receptacle in a
stream, the flow of which is so regulated that the oxides, (say iron ore
or cinder, or any other convenient and suitable oxidizing substance,)
can be stirred or mixed into it. This can be conveniently done by sifting
the oxides reduced to lumps, grains, or powder into the molten metal,
while it is being poured, or otherwise adding them in small quantities
from time to time or continuously. The fluid metal will rapidly become
pasty and then solid, so that it is important to perform the operation
quickly, and if the hardening is inconveniently rapid the oxide should
be used hot. The result will be a sort of crude wrought iron, or, in
other words, some parts of the resultant mass will be wrought iron,
some cast iron, some will be ore, and other particles will be in different
intermediate conditions, and all will be united together in a mechanical
union so closely as to admit of the production of a homogeneous
This mass when cooled
wrought iron by a further application of heat.
will be in most convenient shape for further treatment if the mixture
be made in an ingot mould, which may be of any desirable form.
The material thus obtained is then placed in a reverberatory or other
suitable furnace and exposed to heat, whereby the chemical operations
arrested by the cooling in the first stage of the process will be resumed
and completed, the remaining particles of cast iron being fully reduced
to wrought iron and the impurities sweated out. In this part of the
process it is preferable to use a cinder bottom furnace or a sand bottom
so shaped as to retain cinder enough to keep the iron soft and sticky.
After it has had sufficient heat to accomplish the purpose indicated,
that is to say, to complete its conversion into homogeneous wrought iron,
it is ready to be drawn and hammered, rolled, squeezed, or manipulated
as any other similar shaped mass of wrought iron would or may be used.
If so preferred, the crude mixture may be made in any shape, in
flakes, plates, and other forms, and then worked as by the ordinary
process of working scrap; or the ingots may be broken up when first
hot (at which time they are very friable), the pieces spread over the
furnace bottom, and then balled up; but it is preferred to make the
crude or mixed material in the form of an ingot suitable for rolling
in which case I simply give it such turning in the furnace as is needed
to keep it from getting too dry, and after it has become properly

page_text: converted and refined I draw it out in its original shape and put it
through the rolls or other working appliances. But the essential part
of this process is the almost instantaneous conversion of cast iron into
a condition so far akin to ordinary wrought iron that it may be
completely converted into wrought iron of uniform consistency and
highly purified character by the simple after operation of judicious
exposure to heat. The result is obtained at much less cost than
puddling, and the iron produced is decidedly better in quality. This
process is also advantageous in that it enables me to use conveniently
and easily, whenever it is desirable so to do, the fluxes or foreign
substances sometimes introduced into the iron in the processes at
present employed to improve its quality. In the ordinary operation of
puddling it is very difficult to effect such a union between the fluxes
and the iron as to secure the desired result. In this process I mix
them in along with the oxides when the metal is first run off, and thus
secure a thorough and complete admixture of the fluxes and iron as well
as of the oxides and iron, so that under the effect of the high heat to
which the mass is afterwards subjected the desired chemical reactions
take place, and the quality of iron sought after is more perfectly
secured.