IMPROVEMENTS IN THE TREATMENT OF Cast IRON FOR THE PRODUCTION OF CASTINGS THEREFROM
Year: 1870

page_text: LETTERS PATENT to Charles Denton Abel, of No. 20, Southampton
Buildings, Chancery Lane, in the County of Middlesex, Patent
Agent, for the Invention of "IMPROVEMENTS IN THE TREATMENT OF Cast
IRON FOR THE PRODUCTION OF CASTINGS THEREFROM."-A communication
from abroad by Nicholas John Poutiloff, of St. Petersburg, in the
Empire of Russia, Acting State Councillor and Manufacturer.
PROVISIONAL SPECIFICATION left by the said Charles Denton Abel
at the Office of the Commissioners of Patents, with his Petition, ou
the 10th January 1870.
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 THE
TREATMENT OF CAST IRON FOR THE PRODUCTION OF CASTINGS THEREFROM," to be
as follows:-
-
The ordinary method of running molten pig metal direct either from
the blast furnace itself or from cupola or other furnaces into moulds has

page_text: the great disadvantage that the castings thus produced in retaining a
great proportion of all the impurities originally contained in the ore or
introduced into the metal during the process of smelting are in strength
and quality considerably inferior to what they would be had the said
impurities been removed from the metal previous to running the same
into the moulds.
The present Invention has for its object to remove such impurities
from the cast iron by an intermediate process between the melting down
in the cupola or other furnace and the running of the metal into the
mould, and consists in acting upon the molten cast iron by means of
jets of atmospheric air forced through the same inside a suitably closed
vessel (by preference the now well known "Bessemer converter), such
passage of air through the metal being, however (unlike the "Bessemer"
process), arrested after the impurities, such as silicon and manganese,
have been acted upon and converted into slag, and before the carbon of
the metal has been to any extent consumed, so that the result of this
operation is not the production of wrought iron or steel, as in the
Bessemer process, but simply the production of purified cast iron.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Charles Denton Abel in the Great Seal Patent
Office on the 7th July 1870.
·
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
DENTON ABEL, of No. 20, Southampton Buildings, Chancery Lane, in
the County of Middlesex, Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Tenth day of January, in the year of
our Lord One thousand eight hundred and seventy, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Charles Denton Abel, Her special licence that
I, the said Charles Denton Abel, my executors, administrators, and
assigns, or such others as I, the said Charles Denton Abel, my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel

page_text: Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE TREATMENT
OF CAST IRON FOR THE PRODUCTION OF CASTINGS THEREFROM," a communication
to me from abroad by Nicholas Jolin Poutiloff, of St. Petersburg, in the
Empire of Russia, Acting State Councillor and Manufacturer,) upon the
condition (amongst others) that I, the said Charles Denton Abel, my
executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Charles Denton Abel, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say:-
It is well known that iron castings are.at present produced by melting
down the requisite pig iron (according to circumstances and to the nature
of the casting) either in crucibles in reverberatory furnaces or cupola
furnaces, from which the metal is run directly into the moulds; in some
cases even the metal is run directly from the blast furnace into the
moulds for the castings. Each of these modes of proceeding have their
disadvantages and exercise a deteriorating influence upon the castings
produced, which as compared with steel have but little power of resisting
dynamical forces. Although steel in its composition resembles cast iron
very closely it differs from the same, however, in its much greater
purity, that is, in its greater freedom from foreign substances. That
even the quality of steel is increased by careful manipulation and
purification is evident, for instance, from the fact that puddled steel is
considerably inferior in quality to the cast steel prepared therefrom, the
cause of which is that the production of the latter necessitates a re-melting
and purifying of the former at a high temperature, whereby great care
is taken not only to prevent the admixture of foreign substances with
the steel, but also to remove as much as possible the impurities contained
in the puddled steel.
:
}
Now the present Invention has for its object to apply this same
principle of operating as now applied to steel to the treatment of cast
iron. The improvement of the quality of this metal, although it has not
engaged to any extent the attention of manufacturers, is nevertheless of

page_text: great consequence in the production of heavy castings for locomotives,
steam cylinders, rolling mills, toothed gearing, &c., requiring, as these
objects do, peculiar properties in the cast iron employed which shall
afford them the requisite powers of resistance against all dynamical
forces to which they are subjected.
Numerous experiments having been performed by my foreign corre-
spondent with a view to improve the quality of cast iron in order to
impart thereto the properties above alluded to, he has found that from
whatever furnace the cast iron is run directly into the moulds (even
though it be from reverberatory furnaces in which air under considerable
pressure is blown into the molten metal), no satisfactory result is
obtained, because by this method all the impurities and slag which affect
the quality of the metal are not removed therefrom.
Now the present Invention consists in obtaining the desired purification
of the metal by subjecting the same to an intermediate process between
the melting down of the metal in the ordinary furnace (of whatever
description) and the running of the metal into the moulds, such process
consisting in the introduction of the molten cast iron from the furnace
into a separate close receptacle in whicli jets of air under considerable
pressure are forced through the metal.
The apparatus employed for this purpose must fulfil the following
conditions: First, it must allow of a concentration of heat inside it;
second, it must facilitate the passage of the currents of air through the
entire body of the liquid metal; and, third, it must admit of convenient
manipulation and regulation of the process. Open reservoirs or vessels
do not fulfil these conditions, in consequence whereof the forcing of air
through molten cast iron contained in an ordinary foundry ladle (such
as has already been tried) does not lead to any practical result. I
employ therefore for this process the apparatus known as the "Bessemer
converter," and which up to the present time has only been employed
for the production of wrought iron and steel. In forcing air through
the fluid cast iron in such converters the greater portion of the silicon
and manganese is first converted into slag, after which the combustion
of the carbon is effected accompanied by a boiling of the metal and by
the issuing of bright flames and seintillations from the converter, where-
upon the metal is converted first into steel and then into wrought
iron. According to the present Invention, however, the above process is
interrupted at the moment when the greater portion of the silicon and

page_text: the manganese has been formed into slag, and before the combustion of
the carbon has been effected to any extent, thus producing cast iron
retaining all its characteristic properties, but purified from substances,
such as silicon, which render it brittle. At the same time the cast iron
is by the chemical process induced by the introduction of the air raised
to a very high temperature, and consequently rendered exceedingly
fluid, facilitating the rising of the slag to the surface, and thus leaving
the cast iron in a very pure state.
This improved process is carried out in the following manner:-The
raw metal is first melted down in any suitable furnace, or it may be run
direct from the blast furnace into a Bessemer converter, in which air
blast is then maintained until the before-mentioned reaction has taken
place, after which the cast iron will be found to be in the desired purified
state. From the converter the metal is then run either directly into the
moulds for the castings or into an ordinary foundry ladle. The castings
prepared according to the above process are susceptible of being con-
siderably hardened and are remarkable for their great strength..
Having thus described the nature of this Invention, and in what
manner the same is to be performed, as communicated to me by my
foreign correspondent, I wish it to be understood that I in no way claim
the forcing of air through molten cast iron contained either in foundry
ladles, reverberatory or cupola furnaces, nor the subjecting of molten
cast iron to the action of currents of air in Bessemer converters for the
production of wrought iron or steel therefrom; but what I claim is,
treating inolten cast iron by means of currents of atmospheric air in
Bessemer converters or analogous apparatus in such manner as to
produce purified cast iron for use in castings, substantially as herein-
before set forth.
In witness whereof, I, the said Charles Denton Abel, have hereunto
7
set my hand and seal, this Sixth day of July, in the year of our
Lord One thousand eight hundred and seventy.
CHA³. D. ABEL. (L.S.)