Improvements in the Manufacture of Steel.
Year: 1892

page_text: Date of Application, 26th Jan., 1892
Complete Specification Left, 24th Oct., 1892-Accepted, 3rd Dec., 1892
* PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Steel.
GEORGE WILLIAM CLARK, of 80 Great Brook Street, City of Birmingham,
County of Warwick, Metallurgist, do hereby declare the nature of this invention
to be as follows:-
-
The object of the present invention, is to diminish or entirely remove, the
blow-holes in molten steel, and by the same means, by a longer application
of the process, to improve the quality of such steel, from which the gases have
been eliminated.
In carrying out my invention, I produce a fusible slag, composed of any
silicate of alumina, calcium hydrate (slacked lime), and carbon (with or without
fluor-spar or other flux) in such proportions, that the lime shall take up, or
combine with, all or nearly all of the silica in the said silicate of alumina, and
that the carbon shall, by preference, be in excess of the theoretical quantity*
required to combine with the oxygen of the H2O of the calcium hydrate.
.
These materials are intimately mixed and kneaded with water into a compact.
mass, and then fused to a slag by any suitable means out of contact with the air
(as far as possible). Such slag is then moulded on the end of an iron bar or
rabble or other suitable apparatus, as a knob or billet, and the slag when solid or
set is then forced into or under the surface of the molten steel in any convenient
manner, and is then preferably stirred through the same. The slag so produced
may either be used in the Bessemer or other converter, after the blowing is
finished, or in the ladle holding the molten steel produced by the Bessemer or other
process, or into the bath of molten steel in any suitable furnace, such for instance,
as the open-hearth or other steel furnace, or into the pots used in making crucible
cast steel. In this manner the fusible slag above described, gradually inelts and
removes or diminishes the gases forming blow-holes (so prejudicial in cast steel)
owing to the liberation of aluminium contained in the said slag. The time required
to complete the removal of the said blow-holes may be determined by practice,
and again, by extending the said time, an alloy of aluminium with the molten steel
may be formed by which its quality is improved as may be required.
Dated this 26th day of January 1892
-
GEORGE WILLIAM CLARK.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Steel.
GEORGE WILLIAM CLARK, of 80 Great Brook Street, City of Birmingham,
County of Warwick, Metallurgist do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:―
The object of the present invention, is to diminish or entirely remove, the
blowholes in molten steel, and by the same means, by a longer application of the
process, to improve the quality of such steel, from which the gases have been
eliminated, by removing or diminishing sulphur when present in such steel, thereby
improving the manufacture thereof.
In carrying out my invention, I produce a fusible slag from the following
materials; silicate of alumina, calcium hydrate, and carbon (with or without fluor
spar or other flux) in such proportions, that the lime shall take up, or combine with
all of the silica in the said silicate of alumina, and which lime shall be in excess of

page_text: such proportion, when it is required to make the said slag less fusible, or to remove
or diminish sulphur when present in steel, (or iron intended for the manufacture of
steel). The carbon in the said mixture I prefer to be also in excess of the
theoretical quantity. required to combine with the oxygen of the H₂O of the said
calcium hydrate used in the mixture.
The proportions of these materials I have found in practice to give good results
are, 35 parts by weight of ordinary brown clay (for silicate of alumina) 26 parts of
calcium, hydrate (which may be increased as above described) and 7 parts of
charcoal (more or less) but which proportions may be varied: according to the
percentage composition and purity of such materials, and also as the nature of
the steel under treatment may require. In some cases I find it beneficial to
add to the mixture, 7 parts (more or less) of common salt or commercial spirits
of salts.
.
J
These materials are intimately mixed, and ground to powder in any suitable mill,
they are then kneaded with water into a compact plastic mass, and formed into
lumps or balls of convenient size, which are then dried and fused to a slag by any
suitable means, out of contact with the air (as far as possible). The slag so
produced is then moulded on the end of an iron bar or, rabble, or other suitable
apparatus, as a knob or billet, and such slag when solid' or set, but still warm; is
then forced into or under the surface of molten steel in any convenient manner,
and is preferably stirred through the same. Or otherwise, the 'slag so produced
may either be used, for the object specified, in the Bessemer or other converter
after the blowing is finished. The slag may also be used in the ladle holding the
molten steel produced by the Bessemer or other process of steel making. In this
case. it may either be used as a billet as above described, or such slag may be
melted and poured into the said ladle, and the molten, steel poured upon it, after
such slag has set, but is still warm, or it may be ground to powder and be mixed or
incorporated with the lining of such Indle.
As it is necessary to bring the molten steel into intimate contact with the said
slag, such slag may also be melted and poured into the said ladle, and while still.
fluid, the molten steel may be poured' upon it through a diaphragm or tray,, pierced
with holes, so as to divide the main stream of molten steel into several smaller
streams or, the stream of molten steel. may be so arranged when pouring it so as to
fall or impinge upon a refractory stud or prop, of fireclay or other suitable material,
thereby to break up such stream, and distribute it in drops amongst the molten
slag beneath it. Or otherwise, the slag so produced may be forced into the bath
or charge of molten steel in any suitable furnace, such for instance as the open-
hearth, or it may be used in the puddling furnace for puddled steel. In:a. similar
manner the said slag, or the materials. forming the said slag, may be used at any
suitable stage in the manufacture of iron intended for the manufacture of steel,
when more convenient to do so, thereby securing to the steel produced from such
iron, the benefit of my process, herein before described, at an earlier stage of its
manufacture. The said slag, may also be mixed with the pieces of metal used in
the crucibles for. making crucible cast steel. Also the materials above described,
from which the said slag is produced may be used for a similar purpose as the said
slag, for the object. specified, without previously melting them to a slag by a
distinct operation thus shortening the process.
By the operation of the. process hereinbefore described, the steel is rendered
more fluid, and when pouring such improved steel from a ladle or furnace into any
mould or otherwise, I surround the falling stream of fluid steel with an atmosphere 5
of ordinary coal gas to protect the steel from partial oxidation.
Having thus 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 :-
1st. The process of diminishing or removing blowholes in molten steel, by means of
the slag, or materials forming such slag, and the method of using the same, thereby

page_text: improving the manufacture of such steel, substantially as herein described and
set forth.
2nd. The process of eliminating in whole or part, sulphur from steel and from
iron intended for the manufacture of steel by means of the slag or materials
forming such slag, thereby improving the manufacture of steel and of iron intended
for the manufacture of steel, substantially as herein described and set forth.
3rd. The employment of the materials. herein described, in or about the
proportions stated, for the purpose stated or specified substantially as herein
described and set forth.
4th. The process of surrounding the stream of molten steel (when in the act of
pouring it) with an atmosphere of ordinary coal gas, so as to prevent such steel
from partial oxidation, substantially as herein described and set forth.
Dated this 24th day of October 1892.
GEORGE WILLIAM CLARK.