IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL."
Year: 1879

page_text: LETTERS PATENT to George Edward Dering, of Lockleys, near Welwyn, in the
County of Herts, Esquire, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF IRON AND STEEL."
PROVISIONAL SPECIFICATION left by the said George Edward Dering
at the Office of the Commissioners of Patents on the 20th December 1879.
GEORGE EDWARD DERING, of Lockleys, near Welwyn, in the County of Herts,
Esquire. "IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL."
Some descriptions of cast iron, and amongst them some Swedish and other
varieties of exceptional purity as regards phosphorus and other hurtful foreign
substances are, as is well known, deficient of silicon, and therefore unsuitable for
treatment by the ordinary Bessemer process, as the requisite temperature cannot be
obtained. In order to be enabled to deal satisfactorily with such irons, and obtain
high class steel from them by the pneumatic process of conversion, I line the
convertor in which they are to be treated with a basic or with a carbonaceous
lining, and work under excess of pressure by checking the egress of the issuing
gases from the convertor by any suitable means, or I inject powdered or vaporous
fuel with the blast, or I make use of both these methods conjoined, the use of
purifying reagents being superadded in combination with either or both of them if
desirable. I similarly employ excess of pressure in the convertor, which may in
this case have a siliceous or basic or carbonaceous lining, or injection of powdered
or vaporous fuel with the blast, or both methods conjoined, in order to obtain a
sufficient elevation of temperature for the successful "blowing" of metal that has
been previously de-phosphorized by any treatment which has likewise had the
effect of depriving the iron of all or part of its silicon, as for example, those
methods consisting in treating the molten metal at a comparatively low temperature
by metallic oxides.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George Edward Dering in the Great Seal Patent Office on the 19th
June 1880.
GEORGE EDWARD DERING, of Lockleys, near Welwyn, in the County of Herts,
Esquire. "IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL."
Some descriptions of cast-iron, and amongst them some Swedish and other
varieties of exceptional purity as to the presence of phosphorus and other hurtful
foreign substances are, as is well known, deficient of silicon, and therefore un-
suitable for treatment by the ordinary Bessemer process, because the requisite
elevation of temperature cannot be obtained. In order to be enabled to deal
satisfactorily with such irons and obtain high class cast steel (or ingot iron) from
them by the pneumatic process of conversion, I line the convertor in which they
are to be treated with a basic or with a carbonaceous lining, and work under
excess of pressure by checking the egress of the issuing gases from the convertor,
according to the methods, consisting essentially either in constructing the mouth of
the convertor of very contracted proportions, or the use of a regulating conical plug
of refractory material to restrict the outflow of the gases, described and delineated
by Bessemer, in relation to ganister-lined convertors in the Specification of his
Patent, No 1433, of the year 1869, or by any other suitable means, powdered or
liquid, or vaporous or gaseous fuel or combustible matter being, if desirable, injected
by or with the blast, so as to still further increase the temperature, and the use of
purifying reagents being sometimes superadded with advantage.
The mode which I prefer of carrying out this part of the Invention is to line
the convertor-casing, which should be made of stouter plates than usual, so as to
withstand the greater internal pressure, and constructed so as to be air-tight at the
joints after the manner of making a steam-boiler, with basic bricks manufactured
under excessive pressure, in accordance with my Patent, No. 1682, of the year 1879,
(although other descriptions of basic bricks may be employed) to check the exit of
the gases from the convertor by the interposition of a flat disc of like material
traversing laterally the mouth of the convertor, backed and framed with iron in
such a manner that the issuing gases shall not impinge upon the metal, and
regulated by screw or lever means of adjustment, and to work at a pressure of from
1 to 2 atmospheres within the convertor. If a carbonaceous lining is used to the
convertor, the metal may have the residual excess of carbon removed by subsequent
blowing" in a siliceous-lined convertor, according to the method described in and
forming the seventh claim of my Patent, No. 4904, of the year 1879.
I similarly employ excess of pressure in the convertor, which may in this case
have a basic or carbonaceous or (which I prefor) a siliceous lining, or injection of
powdered or liquid or vaporous or gaseous fuel or combustible matter by or with
the blast, or both methods conjoined, in order to obtain a sufficient elevation of
temperature for the successful "blowing" of metal that has been previously de-
phosphorised by purifying treatment, which has likewise had the effect of depriving
the iron of all or part of its silicon; as for example, the well known method
consisting in treating the molten metal at a comparatively low temperature by
means of metallic oxides, proposed and patented by Mr. Isaac Lowthian Bell.
The instructions hereinbefore given in reference to the first part of the Invention
as to the method I consider best to employ for working under excess of pressure in
the convertor will apply equally to the present part of it, so that it is un-necessary
to repeat them. For carrying out the injection of combustible matter by or with
the air blast, the plans I prefer to adopt are to blow in coal dust or to impregnate
the air with the vapour of petroleum; but as there is nothing new in itself in
either of these ways of obtaining an increase of temperature when purifying or

page_text: converting metal by the Bessemer process, it is not requisite to particularly
describe the mode of conducting them. Between the two separate operations, the
combination in consecutive order of which constitutes this part of the Invention,
namely (1st), the (generally comparatively low-temperature) de-phosphorising and
de-silicurising operation, and (2nd) the "blowing" operation, it is obviously
unnecessary and unadvisable to allow the metal to cool and solidify, but best to
pour it after the first treatment direct into the Bessemer convertor, the same being
previously brought to a high temperature in the interior, according to the ordinary
practice.
Having thus described the nature of my Invention, and the mode of putting the
same into practice, I wish it to be understood that I make no general claim either
to conducting the Bessemer process under excess of pressure in the convertor, or the
injection of powdered or liquid or vaporous or gaseous combustible matter, by or
with the air blast into the Bessemer convertor, or to low-temperature or other
de-phosphorising operations. But what I claim is,-
First. The treatment of those kinds of cast-iron which are more or less deficient
of silicon, and therefore apt to "blow cold" as it is termed, in a Bessemer convertor,
under the combined conditions of working as heroin described, consisting namely in
the convertor being lined with a basic or carbonaceous lining, and in combination
with the use of such a convertor, conducting the "blowing" operation under excess
of pressure in the convertor, powdered or liquid or vaporous or gaseous combustible
matter also being, if desirable, injected by or with the air blast, so as to still
further increase the temperature.
Second. Treating molten cast-iron by two successive operations, substantially as
herein described, the first consisting in a (generally comparatively low-temperature)
purifying process, by which both phosphorus and also more or less silicon are
removed, the second operation consisting in subsequently "blowing" such partly
purified metal (which is apt to "blow cold," owing to deficiency of silicon) in a
Bessemer convertor, the Bessemer process being conducted under excess of pressure
in the convertor.
Third. Treating molten cast-iron by two successive operations, substantially as
herein described, the first consisting in a (generally comparatively low-temperature)
purifying process by which both phosphorus and also more or less silicon are
removed, the second operation consisting in subsequently "blowing" such partly
purified metal (which is apt to "blow cold," owing to deficiency of silicon) in a
Bessemer convertor, powdered or liquid or vaporous or gaseous combustible matter
being injected by or with the air blast.
Fourth. Treating molten cast iron by two successive operations, substantially as
herein described, the first consisting in a (generally comparatively low-temperature)
purifying process, by which both phosphorus and also more or less silicon are
iemoved, the second operation consisting in subsequently "blowing" such partly
purified metal in a Bessemer convertor, the Bessemer process being conducted under
excess of pressure in the convertor, and also powdered or liquid or vaporous or
gaseous combustible matter being injected by or with the air blast.
In witness whereof, I, the said George Edward Dering, have hereunto set my
hand and seal, this Eighteenth day of June, in the year of our Lord One
thousand eight hundred and eighty.