Year: 1887

page_text: Date of Application, 28th June, 1887
Complete Specification Left, 28th Mar., 1888
Complete Specification Accepted, 28th Sept., 1888
1, ALFRED GRIFFITHS GREENWAY of West Derby in the County of Lancaster,
Medical Doctor, do hereby declare the nature of this invention to be as follows:-
This invention has for its principal object a process for purifying or removing
impurities from iron, steel, spiegeleisen, manganese iron and other like metals, while
in the liquid state, and also for apparatus therefor.
It consists essentially in passing through- the metal, while in a molten state, a
current of electricity, by which means a molecular change appears to be induced in
the iron, gaseous impurities are eliminated in considerable quantity, and its tenacity
and homogeneity are greatly increased.
In carrying out the invention the metal is melted in any suitable furnace or cupola
fitted with electrodes refractory in the metal passing through fireclay in the sides
or bottom of the furnace or cupola and dipping down into the molten metal. Or
in place of this the molten metal is placed in a receiver (usually and preferably
heated externally) fitted with electrodes refractory in the metal and impurities oporated
upon. I prefer to use gas-coke-carbon, or other similar carbon. As however, the
projecting part of the carbon exposed to the air, rapidly burns away, I propose to
use carbons thickly coated on the exposed part which appears above the metal with a
mixture of fibrous asbestos and fire clay, or to enclose the carbon in a porcelain cover
dipping into the iron. The continuous current of electricity in one direction produced
by a Siemen's dynamo, I have found admirable for the purpose, but other sources of
electricity can be used, quantity being required rather than intensity. The electricity
passing through the molten iron or steel apparently purifies it from some noxious
ingredients, especially occluded gases, as no sooner does the passage of electricity tako
place than for a considerable time an ebullition more or less violent ensues. My
invention will therefore be very useful for Bessemer and other cast steel ingots.

page_text: The amount and intensity of the electric current necessary, and the time required
will naturally vary with the quality and quantity of the iron, I can therefore only
give an example of a successful experiment, 200 lbs. of Cleveland No. 3 iron with
a breaking strain of 25 hundred weights on a bar, one inch wide, two inches deep and
three feet between supports,-load in contre, was melted, placed in a crucible in a
wind furnace, and a charge of 9.5 ampères of a current of 185 volts from a Siemen
dynamo, was passed through for half an hour, the iron was now found under
similar conditions to the previous test-to have a breaking strain of forty hundred
weights.
This process can be used alone or combined with air injection as in Bessemer's
process, and can be applied before, after, or alternating with the blowing in of air,
and the addition of spiegeleisen, but I prefer it mainly after these operations.
T
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Agents for the Applicant.

page_text: I, ALFRED GRIFFITHS GREENWAY of West Derby in the County of Lancaster,
Medical Doctor, do hereby declare the nature of my said invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention has for its object a process for purifying or removing impurities
from iron used in the manufacture of Steel, or from steel produced from the iron
while in the liquid state.
It consists essentially in passing through the metal while in a molten state a
current of electricity in conjunction with air, by which means a molecular change
appears to be induced in it, the gaseous impurities are eliminated in considerable
quantity, and the tenacity and homogeneity of steel so produced are greatly
increased.
For electrodes I prefer to use the hard form of carbon found in gas retorts, or
other similar carbon.
The continuous current of electricity produced by a Siemen's dynamo I have found
admirable for the purpose, but other sources of electricity can be used, quantity being
required rather than intensity, and a current continuous in one direction being
preferable to an intermittent one or one periodically reversed. The electricity and
air passed through the metal purifies it from some noxious ingredients, especially
occluded gases, as no sooner does the passage of electricity tako place than for a con-
siderable time an ebullition more or less violent ensues. Therefore "Bessimer" cast
steel produced by this process possesses considerably increased homogeneity and
value.
The amount and intensity of the clectric current necessary, and the time required,
will naturally vary with the quality and quantity of the metal to be operated upon.
The electricity can be applied in the process before, after or alternating with the
blowing in of air, and the addition of spiegelisen, but I prefer it mainly after these
operations, and either in the ingot itself, or in the ladle.
In the Drawings which serve to illustrate my invention, Figure 1 is a side elevation
in section of a "Bessimer" converter, and
Figure 2 is a section of an ingot mould with improvements according to my inven-
tion applied thereto.
Figure 3 shows a ladle provided with means for carrying out my invention.
With reference in the first instance to Figure 1, A designates the converter, and A¹
the converter bottom containing the tuyeres B arranged in the usual way. Care
the electrodes, and D the porcelain tubes, through which the electrodes pass, and by
which they are insulated from their surrounding substances. The electrodes it will be
seen lie near the bottom of the converter and in such a position that the air issuing
through the tuyeres will not come in contact with them. In operation the current of
electricity is either supplied simultaneously with the blowing or before or after it is
passed through the molten metal in the manner above described.

page_text: With reference to Figure 2 the electrodes Care placed in the mould A, one at each
end, that is one of such electrodes is placed in the cover of the mould, and one in its
bottom, and are insulated by porcelain tubes D in the same manner as above set
forth. Obviously in this case the process of blowing, only, need be conducted in the
converter A.
In Figure 3 is shown an arrangement of electrodes C for operating upon the
molten metal, while in the ladle A, said electrodes being mounted in a cross-
head H supported by a chain I which is capable of being lowered and raised by
overhead gear of any known kind. In this instance as well as that set forth with
reference to Figure 2, the metal is first subjected to the air blowing process, and
subjected only to the electric treatment in the ladle. After blowing the metal is
run from the converter into the ladle in any known way, and the electrodes are
then lowered into the metal which is then subjected to the electric current as above
described.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. In the manufacture of steel, the herein described process of purifying the metal,
which consists of blowing air through the molten metal, by which means some of the
carbon and other matter is eliminated and the temperature increased, and of treating
it while molten with electricity, either before, after or during the blowing.
2. The steel ingots produced from iron through which air has been passed, and
which has been treated with electricity, while in a molten state, substantially as
described.
Dated this 20th day of September 1888
CHEESBROUGH & ROYSTON,
Applicant's Agents.