Improvements in and Connected with the Manufacture of Iron.
Year: 1888

page_text: Date of Application, 28th Apr., 1888
Complete Specification Left, 28th Jan., 1889-Accepted, 27th July, 1889
PROVISIONAL SPECIFICATION.
Improvements in and Connected with the Manufacture of Iron.
I, ALFRED GRIFFITHS GREENWAY, of West Derby, in the County of Lancaster,
Doctor of Medicine, do hereby declare the nature of my said invention to be as
follows:-
The present invention rolates, namely, to the production of "cast iron," which is
used, or applicable for use for "castings" employed in the arts, and manufactures,
or for after treatment, or use in metallurgical processes, or manufactures; the metal
from which it is melted being pig, scrap, or cast iron of any sort, which has already
been reduced from its ore.
The object of the invention is, chiefly, to provide a process by which cast iron is
produced, which when it is ran into moulds or formed into castings shall possess
greater strength than hitherto, or which if further treated, or used shall yield a metallic
product of an improved nature.
The process of producing the improved iron, involving my invention, consists in
subjecting metal whilst in a molten state to the influence of an electric current, such
metal being interposed within the circuit, in such a manner, as to form a continuous
part of the same, and in conjunction therewith introducing and passing air through
it to effect thereby a greater or less decarburization of the metal.
The combined effect of the electric treatment of the metal, and the passing of air
through it, is the production-of a metal, which when cast and cold; is of greater-
strength than is possessed by cast iron, produced from similar material, by processes
hitherto practised.
An apparatus in which the above process can be conveniently carried on, may be
of the "cupola" type, in which the cast iron is brought to a molten state in the upper
portion, and the combined electric and pneumatic process is effected in the lower part.
In such a case the air used for melting the metal would be by preference introduced
into the side of the cupola, above the apertures by which the decarburizing air is
introduced into the metal, and also above the electric conductors, or electrodes.
If the cupola, or apparatus be of that type in, or in connection with which a
receiver is employed, the electric and pneumatic processes can be both conducted in the
receiver, or the cupola; or, one may be conducted in the receiver, and the other in the
cupola.
If it is desired to add carbon, or any substance to the metal after it has been
decarburized, or treated as described, it may be effected by introducing into the
cupola or receiver ferro manganese, spielgeleisen, or other substance in any suitable
manner.
The conductors or electrodes used to convey the electricity through the metal may
be arranged in any convenient way. For instance they may be suitably arranged in
the lower portion of the cupola, but so disposed that they would not be effected
detrimentally by the air blast. As a further protection-assuming carbon to be the
substance from which the electrodes are made they are coated with refractory
material and one which is a bad conductor of electricity. Electricity from any
suitable source such as a dynamo-electric machine may be used in the process.
The electric and pneumatic processes or treatments may be conducted either
simultaneously, or consecutively in either of the two possible orders.
Different forms of apparatus may be devised to meet the requirements of special
cases, but in all the essential feature is the use of an apparatus so constructed that..

page_text: the processes or treatments above set forth may be carried on in- such a manner as
to effect the ends and results, as, or substantially as described.
Dated this 27th day of Annil 1889
ALFRED GRIFFITHS GREENWAY.
By Cheesbrough & Royston,
Agents.
COMPLETE SPECIFICATION.
Improvements in and Connected with the Manufacture of Iron.
I, ALFRED GRIFFITHS GREENWAY, of Crosby Green, West Derby, in the County
of Lancaster, Doctor of Medicine, do hereby declare the nature of my said inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
The present Invention relates mainly to the production of cast iron which is used
or applicable for use for castings employed in the arts and manufactures, or for after
treatment or use in metallurgical processes or manufactures, the metal from which it
is melted being pig, scrap, or cast iron of any sort which has already been reduced
from its ore.
The object of my Invention is chiefly to provide a process by which cast iron is
produced, which when it is run into moulds or formed into "castings" shall possess
greater strength than hitherto, or which if further treated or used shall yield a metallic
product of an improved nature.
The process of producing the improved iron involving my Invention consists in
subjecting metal whilst in a molten state to the influence of an electric current, such
metal being interposed within the circuit in such a manner as to form a continuous
part of the same, and in conjunction therewith introducing air to effect a greater or
less decarburization of the motal.
The combined effect of the electric treatment and the passing of air through the
metal, is the production of a metal which when cast and cold is of greater strength
than is possessed by cast iron produced by similar material by processes hitherto
practiced.
An apparatus in which the above process can be conveniently carried on, may be of
the cupola type, in which the cast iron is brought to a molten state in the upper
portion and the combined electric and pneumatic treatment or process is effected in
the lower part. In such a case the air used for melting the metal would be by
preference introduced into the side of the cupola above tho apertures by which
the decarburizing air is introduced into the metal, and also above the electric
conductors.
If the cupola or apparatus be of that type in or in connection with which a receiver
is employed the electric and pneumatic process may be both conducted in the receiver
or in the cupola, or one may be conducted in the receiver and the other in the cupola.
The conductors or electrodes used to convey electricity through the metal may be
arranged in any convenient way. For instance they may be suitably arranged in the
lower portion of the cupola but so disposed that they would not be affected
detrimentally by the air blast. As a further protection-assuming carbon is the
substance of which the electrodes are made-they are coated with a refractory
material and one which is a bad conductor of electricity.
The electric and pneumatic processes or treatments may be conducted either
simultaneously or consequtively in either of the two possible orders.
In the drawings which serve to illustrate my invention I show two arrangements
of apparatus in connection with which the process described may be conducted.
Figure 1 is a sectional elevation showing a cupola having a vessel for recieving the
molten metal and in which the process herein described may be entirely conducted;
and

page_text: Figure 2 is a sectional elevation of a cupola without a reciever and in which the
process may be entirely conducted.
In the views the same letters of reference are used to denote the same or equivalent
parts.
With reference in the first instance particularly to Figure 1, A designates the
cupola having an ordinary air blast belt chamber a, and air tuyeres a; B is the
reciever communicating with the hearth of the cupola A by a channel C; D designates
the tapping spout of the reciever; E represents a tuyere (of which there may be
several circumferentially arranged) through which the air used for decarburizing the
metal is introduced; G are the electrodes-say of carbon-set in recesses as shown,
insulated by sleeves g', and through which the electric current is passed to and
from the molten metal in the reciever; and H is a pipe by which air and gases from
the reciever pass to the cupola.
The operation of this arrangement is as follows:-
When, by the ordinary method of melting iron in the cupola A, the reciever B
becomes filled to say the level M. M. L., shown in the drawing, the process according
to this invention is commenced; that is to say, air is forced by any suitable means
through the tuyeres E, and the molten metal and the electricity, preferably from a
dynamo-electric-generator, is caused to pass by the carbon electrodes G through the
molten métal, which forms a continuous part of the circuit.
As previously stated these two actions, namely the blowing in of air and the
subjection of the metal to the electric current, may be conducted simultaneously or
in either of the two possible orders, and from results of experiments made according
to the process it appears immaterial as to which of the nodes is employed, and
whichever is used will mostly depend upon the condition of each application of the
invention, and upon expediency.
It will be ovident that the length of time to which the molten metal is treated
with air, that is to a decarburizing process, will vary considerably, as it will in a
great measure depends upon the quality of the material under treatment, the volume
and temperature of air introduced, and the quality of metal required; consequently
the moment at which the blowing in of air must cease, must be judged by the
appearance of the metal or fracture of test pieces or other known modes of obtaining
knowledge of its conditions. But in all casos in which the refined or treated metal is
required to be used for castings, the blowing must not be continued until its condition
becomes thickened or pasty, as a full fluidity for this purpose is obviously essential.
As regards the duration of the electric. treatment, of course this will vary with
different sets of conditions. I have however found in experiments, with 150 lbs. of
ordinary cast iron, that a current of about 10 ampères for a period of from 10 to
30 minutes was sufficient to parify the metal, and that by extending the time of.
subjection no indication of any substantive further improvement was afforded. The
resistance of course is very suiall, the molten metal being a good conductor.
In the apparatus illustrated in Figure 2, the molten metal is subjected to the in-
fluence of the electric current, and the blast of air in the lower portion of the
cupola, the air tuyeres a proper for introducing the melting air being located above.
It will be seen in the Figure the decarburizing air tuyeres E are placed above the
electrodes G as in Figure 1, and are fed through an air belt E¹.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I would state that
different forms and arrangements of apparatus may be designed and used to meet
special cases, and that therefore my invention is not limited to the use of the
apparatus herein particularly set forth, and I declare that what I claim in respect of
the herein described invention.is :-
1. In the manufacture of iron, the process substantially described for purifying
same, consisting of decarburizing the metal while in a molten state by blowing air there-
through, and of treating it with electricity while in a molten state said operations
being effected either simultaneously or successively.

page_text: 2. The process substantially herein described of manufacturing refined or purified
iron from pig or other cast iron, consisting in melting such pig or other cast iron in
a cupola; running the molten metal into a vessel; and then purifying same in said
vessel by treating it with electricity as described and blowing air therethrough..
3. The combination in a cupola for melting iron, of tuyeres, such as E, and.
electrodes, such as G, for the purposes set forth.
4. The apparatus for melting iron, the combination of a cupola adapted to melt
iron; a vessel adapted to recieve and hold the molten iron from the cupola ;
electrodes or electric conductors arranged in or in connection with said vessel;
and tuyeres through which air is introduced into the vessel; substantially as and
for the purposes set forth.
5. A vessel adapted to receive and hold molten iron, and provided with air
tuyeros and electrodes or electric conductors, substantially as and for the purposes set
forth.
Dated this 26th day of Tonnes 1980.
ALFRED GRIFFITHS GREENWAY.
By Cheesbrough & Royston,
15, Water Street, Liverpool, Patent Agents.