LMPROVEMENTS IN THE METHOD OF AND APPARATUS FOR PRODUCING HOMOGENOUS STEEL
Year: 1879

page_text: LETTERS PATENT to Gustaf de Laval, of Stockholm, in the Kingdom of
Sweden, for the Invention of "LMPROVEMENTS IN THE METHOD OF AND
APPARATUS FOR PRODUCING HOMOGENOUS STEEL"
PROVISIONAL SPECIFICATION left by the said Gustaf de Laval at the Office
of the Commissioners of Patents on the 19th December 1879.
GUSTAF DE LAVAL, of Stockholm, in the Kingdom of Sweden. "IMPROVEMENTS
IN THE METHOD OF AND APPARATUS FOR PRODUCING HOMOGENOUS STEEL."
This Invention has for its object the production of steel of more regular density
when the same is cast in a cast iron mould or cockle than is now usually the case,
and consists in providing the upper part of the cockle with an addition or ring of
refractory substance, together with a lid to fit the same. When the steel is about
to be cast the ring and lid are heated to whiteness, the ring is then applied to the
cockle and the steel poured in, whereupon the opening is closed by the lid, and the
whole allowed to cool. In some cases it is desirable to accelerate the cooling of the
steel by the application of water to the lower part of the cockle. By these means
the mass of steel is cooled gradually from the sides and bottom in such a manner as
to ensure the homogenity of the metal so cast, and to prevent the formation of the
cylindrical hole or hollow with an oxidised surface so often produced when steel is
cast in the ordinary way.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Gustaf de Laval in the Great Seal Patent Office on the 15th June
1880.
GUSTAF DE LAVAL, of Stockholm, in the Kingdom of Sweden.
"IMPROVEMENTS
IN THE METHOD OF AND APPARATUS FOR PRODUCING HOMOGENOUS STEEL"
This Invention has for its object the production of steel of more regular density
when the same is cast in an iron mould, cockle, or kokill, than is now usually the
case, and consists in providing the upper part of the cockle with an addition or
[Price 4d.]

page_text: ring of refractory substance, together with a lid to fit the same. When the steel is
about to be cast the ring and lid are heated to whiteness, the ring is then applied
to the cockle and the steel poured in, whereupon the opening is closed by the lid,
and the whole allowed to cool. In some cases it is desirable to accelerate the
cooling of the steel by the application of water to the lower part of the cockle. By
these means the mass of steel is cooled gradually from the sides and bottom,in
Buch a manner as to ensure the homogenity of the metal so cast, and to prevent the
formation of the cylindrical hole or hollow with an oxidised surface so often
produced when steel is cast in the ordinary way.
In order that the foregoing'may be more easily understood, Drawings are attached
hereto, of which the following is a description:-Fig. 1 represents a vertical section
of a casting of steel made according to the method ordinarily adopted; Fig. 2, a
similar view of a casting made in accordance with my method, and Fig. 3, a vertical
section of the apparatus employed in carrying out this Invention. The said
apparatus consists of, A, a cockle, kokill, or mould made of pig or cast iron; B, a
ring of fireproof or refractory substance, and C, a lid or cover of similar material;
Fig. 4 represents a section of steel as cast in the usual way in a cockle or kokill; Fig. 5,
a section of steel when the cockle has been cooled near the bottom; Fig. 6, a similar
section when cooled near the top: Fig. 7, a further similar section when the heated
fireproof ring has been applied to the cockle; Fig. 8, a section when both ring and a
lid heated to whiteness have been applied, and Fig. 9, a section of the steel when
the heated ring and lid have both been applied, and the cockle cooled near the
bottom. In practice it may be so arranged that the lid of the crucible may serve
as the lid of the cockle, the said lid having been suitably heated in its usual
Bervice.
In the case of steel that congeals rapidly and then becomes more or less lumpy,
that is to say, a steel of a lesser degree of hardness, it is often necessary, especially
if the steel is not too warm, to cool the lower part of the cockle with water, so as
to cause the steel to congeal more from the bottom upwards than would otherwise
be the case.
Having now described and particularly set forth the nature of this Invention,
and the manner in which the same is or may be used or carried into effect, I
would observe in conclusion that I do not confine or restrict myself to the precise
details or arrangements which I have described or referred to, as variations may be
made therefrom without deviating from the principles or main features of this
Invention, but what I consider to be novel and original, and therefore claim as the
Invention secured to me by the hereinbefore in part recited Letters Patent is,-
First. The construction of a ring B and lid C of fireproof substance, and the
heating and application of them to a cockle A, as herein described and shown on
the Drawings.
Second. The method, namely, the application of water to the cockle so as to
produce a more regular congelation of the steel from the bottom to the top, and
thereby prevent the formation of hollows in the steel casting, as herein described
and shown on the Drawings.
In witness whereof, I, the said Gustaf de Laval, have hereunto set my hand
and seal, this Eighth day of June, in the year of our Lord One thousand
GUSTAF DE LAVAL. (L.S.)