IMPROVEMENTS IN THE MANUFACTURE OF WROUGHT-IRON WHEELS
Year: 1877

page_text: LETTERS PATENT to Louis Schwartzkopff, of Berlin, Kingdom of Prussia, for
the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF WROUGHT-IRON
WHEELS"
Sealed the 14th August 1877, and dated the 19th February 1877.
PROVISIONAL SPECIFICATION left by the said Louis Schwartzkopff, at the
Office of the Commissioners of Patents on the 19th February 1877.
LOUIS SCHWARTZKOPFF, of Berlin, Kingdom of Prussia.
MANUFACTURE OF WROUGHT-IRON WHEELS."
"IMPROVEMENTS IN THE
The object of the present Invention is to make the nave and the spokes of
wrought-iron wheels, especially for railway carriages, without any weld and out of
a single bloom. For this purpose I use a mould of cast iron or other suitable
material consisting of two parts, each part having on its face the half mould of the
nave and spokes to be produced. Moreover, the upper part has in its centre an
opening of about the diameter of the nave, and of a length sufficient to contain the
bloom out of which the nave and spokes are to be made. The two parts of the
mould are firmly bolted together and placed under a powerful hydraulic press
connected to an accumulator or other arrangement for storing-up water pressure. A
bloom of proper size, to which a welding heat has been given, is then thrown into
the aforesaid central opening of the upper part of the mould, and by means of the
hydraulic press a piston is made to enter into this opening, thereby pressing or
squeezing the material of the bloom during its soft state into all the cavities of the
mould, so as to complete the nave with the spokes at a single operation. The parts
of the mould are then separated and the finished piece is taken out.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Louis Schwartzkopff in the Great Seal Patent Office on the 15th
August 1877.
LOUIS SCHWARTZKOPFF, of Berlin, Kingdom of Prussia.
MANUFACTURE OF WROUGHT-IRON WHEELS."
"IMPROVEMENTS IN THE
The object of the present Invention is to make the nave and the spokes of
wrought-iron wheels, especially for railway carriages, without any weld and out of
a single bloom. For this purpose I use a mould of cast iron or other suitable
material consisting of two parts, each part having on its face the half mould of the
nave and spokes to be produced. Moreover, the upper part has in its centre an
opening of about the diameter of the nave, and of a length sufficient to contain the
bloom out of which the nave and spokes are to be made. The two parts of the
mould are firmly bolted together and placed under a powerful hydraulic press
connected to an accumulator or other arrangement for storing up water pressure. A
bloom of proper size, to which a welding heat has been given, is then thrown into
the aforesaid central opening of the upper part of the mould, and by means of the
hydraulic press a pistor is made to enter into this opening, thereby pressing and
squeezing the material of the bloom during its soft state into all the cavities of the
mould, so as to complete the nave with the spokes at a single operation. The parts
of the mould are then separated and the finished piece is taken out.
Such being the nature of the said. Invention I now proceed to describe the
manner of carrying it into practical effect.
The apparatus or mould which I use is represented in Fig. 1 and 2 of the accom-
panying Drawing,.Fig. 1 being a vertical section according to the line x, y, z, of the
plan, showing the finished nave N and one of the spokes S, and Fig. 2 being the
lower part of the mould in plan. The mould consists of the two parts O and U,
made by preference of cast iron, each part having cavities corresponding to one half
of the described forging. The upper part O is strengthened by the wrought-iron
rings R and R¹, whilst at the junction of the two mould parts a ring C is fixed to
one of them; the two parts are firmly connected together by the bolts B, B. The
part O has to be of such a height that its central opening H, together with the
centre recess in the lower part, will take up the bloom out of which the desired
forging is to be made. P is a piston fitting loosely into the opening H, and
operated upon by a powerful hydraulic press of any suitable design; this press has
to be worked from an accumulator or other arrangement for storing up water
pressure, so as to impart a comparatively quick motion to the piston P. In the
lower part U of the mould there is a round hole H³ corresponding to the hole L in the
nave, which, however, is closed by a cylindrical plug D during the main part of the
process, as will be explained hereafter.
The mould being placed on a truck, of which only the top part W is shown in
the Drawing, is conveyed by the same under the press and properly supported on
the bed plate Z of the latter. A bloom of suitable size, to which a welding heat
has been imparted, is then put into the opening H and the piston is made to
descend, thereby forcing the material of the bloom during its soft state into all the
cavities of the mould, so as to finish the body of the nave N, together with the
spokes S, at a single operation; the pressure required therefor amounts to about
1000 tons.
In this process the main part of the Invention consists:-The hole L in the nave'
may be drilled subsequently, but I prefer to punch the same; in this case the
hole H¹ in the lower part of mould is used. During the described part of the
process, however, it must be closed by the cylindrical plug D of iron or steel
supported by a slightly tapered plate G, under which there is a hole in the bed
plate Z of the press. The body of the nave with the spokes having been finished
the piston P withdrawn and the plate G removed; the plug D will in consequence
fall out of the hole H₁ at once, or during the punching. A steel punch or mandril

page_text: of proper diameter is then placed on the nave and the piston forced down a second
time. The mandril and the punched-out material fall through the holes in the
truck W and the bed plate Z, and may be removed from below. The piston P
having been raised again, and the truck with the mould drawn from under the
press, the bolts B, B, are taken out and the mould is opened for the removal of the
forging.
Necessarily the spokes, as well as the nave, must be of a shape which will
allow them to be easily detached from the mould, and also the spokes must be
sufficiently tapered lengthwise so that they may freely shrink towards the nave.
By the described process the advantage is attained that the entire forging is made
without any weld. Moreover, the iron becomes very dense on account of the high
pressure, and the fibres pass in regular curves from the nave into the spokes, in
which they assume a parallel direction, as has been proved by a forging turned off
to the middle and then etched by an acid. The wheels made with such naves and
spokes will consequently be stronger than other wheels, even if they are lighter;
they may be manufactured cheaper and present a more elegant form.
If a wheel with a crank for a locomotive engine is to be pressed, the opening H
in the top part of mould, the corresponding recess in the bottom part, and the
piston P must agree with the nave and crank, and the bloom has to be roughly
forged into a similar shape under the hammer.
Having now described the nature and the object of this Invention, and in what
manner the same may be put in practice, I hereby claim as the important feature of
the same, the process of manufacturing the nave and the spokes of wrought-iron
wheels in one piece by pressing a bloom at a welding heat from the centre recess of
a suitable mould into the cavities of the same, as specified.
In witness whereof, I, the said Louis Schwartzkopff, have hereunto set my
hand and seal, this Thirtieth day of July, in the year of our Lord One
thousand eight hundred and seventy-seven.