IMPROVEMENTS IN THE MANUFACTURE OF STEEL CASTINGS
Year: 1880

page_text: LETTERS PATENT to John Imray, of No. 28, Southampton Buildings, in the
County of Middlesex, for an Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF STEEL CASTINGS." A communication from abroad by
Francois Hervier. of Charleville. Ardennes. France.
"
PROVISIONAL SPECIFICATION left by the said John Imray at the Office
of the Commissioners of Patents on the 1st June 1880.
JOHN IMRAY, of No. 28, Southampton Buildings, in the County of Middlesex.
"IMPROVEMENTS IN THE MANUFACTURE OF STEEL CASTINGS." [A communication
from abroad by François Hervier, of Charleville, Ardennes, France.]
In producing steel castings many attempts have been made to avoid the blow
holes and sponginess that are apt to occur in such castings, but the processes tried
for this purpose have involved considerable trouble and expense. This Invention
relates to simple and inexpensive means of avoiding the ovils resulting from such
blow holes or sponginess in steel castings by subjecting the pieces after they are
cast to such pressure as to make the objectionable vacuities disappear. For this
purpose the pieces are cast in moulds of dimensions larger than those of the finished
articles, so as to allow for their subsequent compression. After the pieces are cast
they are reheated and introduced into strong moulds or dies, in which they are
subjected to great pressure or to the blows of a hammer, being thus reduced to the
finished dimensions and having their internal vacuities closed, so that when they
are cut, turned, or planed they present sound metal. In this manner railway
wheels can be cast sound in steel, requiring no separate tyres.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Imray in the Great Seal Patent Office on the 30th November
1880.
JOHN IMRAY, of 28, Southampton Buildings, in the County of Middlesex.
"IMPROVEMENTS IN THE MANUFACTURE OF STEEL CASTINGS." A communication
from abroad by François Hervier, of Charleville, Ardennes, France.
A large number of processes have already been employed to prevent the formation
of air-holes which are produced in running molten steel. Some have been
abandoned on account of the difficulties of application, whilst others are but little
employed owing to the cost, which considerably increases the price of cast steel
articles.
The manner in which it is proposed to get rid of these air-holes is not to try to
avoid their formation while running out the molton steel, but to cause them to
disappear afterwards by submitting the cast articles to either a single or several
stamping operations.
This stamping between matrices of the form of the finished articles which are
cast in a rough state effects a compression, which causes the metallic molecules to
be pressed closely together, thus filling up the spaces occupied by air or by gases,
and causing the air-holes to entirely disappear.
It will thus be seen that this process combines the operations of the manufacture
of cast iron articles in moulds and of the manufacture of wrought iron articles by
stamping. It is this combination of these two operations, as applied to the
treatment of steel, that constitutes the essential feature of this Invention.
As this Invention consists of a process or a mode of operation, it will not be
necessary to describe any apparatus or machines, as those already in use are
employed, that is to say, the same moulds as those used in founderies, and the same
power hammers and presses as used for the manufacture of wrought iron or
steel.
The articles, according to this process, are first cast in a rough form of greater
dimensions than those of the finished articles. The excess of volume to be allowed
to the moulds is calculated according to the probable diminution that the
compression will produce. When the rough articles are made they are placed in a
furnace and heated to the requisite degree of malleability to receive the stamping
operation. This operation is effected by means of a power hammer with matrices
in accordance to the configuration of the steel articles to be produced. It may be
necessary to subject the article to several stamping operations, according to the
complication of the form of the articles and the degree of finish it is desired to
obtain. After each stamping the article is reheated, and finally the burr is removed
by cutting or in a press.
The advantages of the new method will be readily understood, and as steel is now
produced by the Bessemer converter or by the Martin-Siemens furnace at a price
as low as that of cast iron of good quality or as that of forged iron, it is natural to
replace by steel the cast iron of cast articles and the forged iron of forged articles,
and these results may be obtained by the application of this process. By this
process articles may be produced entirely of cast steel which have hitherto been
made of cast iron, such, for instance, as the solid wheels of railway carriages. These
wheels are cast in a rough state and then brought to the desired form by stamping,
the air holes being caused to entirely disappear; the wheels being of steel the rim
will serve as a tire.
It is impossible to enumerate all the articles that may be made according to this
process, and it will suffice to say that it is intended to apply it to the manufacture
of all articles at present made of forged or cast iron, from the largest frames and
parts of machines to the smallest parts of locks, ironmongery, etc.

page_text: This process may be applied to the manufacture of all articles now made of steel,
as well as to those hitherto made in cast or forged iron and in malleable cast
iron.
One of the special applications of this process is to the manufacture of horse
shoes. The steel made by any suitable process is cast in moulds in a rough form as
described, and the rough castings are heated in a furnace so as to reach the desired
degree of malleability, when they are subjected to a stamping process, whereby
solid steel horse shoes are obtained without any air-holes and fulfilling all
requirements.
Having thus described the nature of this Invention, and in what manner the
same is to be performed, as communicated to me by my foreign correspondent, what
I claim under the herein-before in part recited Letters Patent is,-
First. The manufacture of articles in steel without air-holes, the process of which
is characterized by the combined employment of two operations, viz., the casting
of the articles in a rough form and the stamping of the same in matrices, an
operation which by the compression of the metal causes the disappearance of all the
air-holes which may have formed during the casting.
Second. The manufacture of horse shoes of cast steel, substantially as herein
described, and consisting in casting the shoes in a rough form and stamping the
same, whereby all air-holes are caused to disappear.
In witness whereof, I, the said John Imray, have hereunto set my hand
and seal, this Thirtieth day of November, in the year of our Lord 1880.