Improvements in the Production of Chilled Metal Castings.
Year: 1895

page_text: Date of Application, 22nd Jan., 1895
Complete Specification Left, 20th Sept., 1895-Accepted, 26th Oct., 1895
PROVISIONAL SPECIFICATION.
Improvements in the Production of Chilled Metal Castings.
I, EMIL PEIPERS, of Siegen, Westphalia, Manufacturer, do hereby declare
the nature of this invention to be as follows:-
This invention consists in a method of manufacturing chill-hardened rolls, shells,
and other castings, wherein the chill-mould a (see the accompanying drawing) is
provided on its inner surface with tapered recesses or grooves b running in the
longitudinal direction of the mould, as shewn in Figure 1 which is a cross section
of the mould drawn to a larger scale than Figure 2.
In carrying out my invention, I insert strings of common hemp, or equivalent
material, into these recesses or grooves b and then line the chill-mould with a thin
layer of loam or moulding material which may be composed of a moist mixture of
moulder's sand, fresh sand, and graphite. This coating c (see Figure 1) which
must not be too thick, (say about two millimetres,) must be smoothed down evenly
with the loam-board, so that the chilling effect of the chill-mould a on the metal
to be hardened when poured into the mould, may not be hindered or even diminished.
The fact that the chilling has taken place is manifested by the white appearance of
the skin of the casting.
After the thin coating of moulding material on the surface of the chill-mould
has become thoroughly air dried, the strings of hemp are withdrawn from the
recesses or grooves and the chill-moulds are put into a core-oven of appropriate
construction to bake the thin coating of loam or moulding material. Then after
fitting the bottom case d, the chill-mould a, and the top case e, together in the
foundry pit i, and after adjusting or screwing on the parts f, g, h, of the runner, the
casting may take place, the hollow spaces left by the strings in the recesses or
grooves & serving as air-ducts.
By coating the chill-bores with a thicker layer than has been hitherto usual,
(the chill-mould having previously only been covered inside with a solution of
graphite in water, (black-wash)) the sudden chilling of the casting to be hardened,
as heretofore, is obviated so that the skin of the casting is more tenacious and much
less brittle than when manufactured as heretofore.
Special advantages are obtained in the manufacture of long and thick chill-
hardened rolls, such as are commonly used in iron and steel manufacture, because
the tension or hardness of the metal is more evenly graduated, or, in other words,
there is not such a sharp distinction between the hardness of the skin and the
general body of the metal, as hitherto, and therefore cracks in the castings are not
so liable to take place, either during the production or subsequent use, if the casting
has been properly effected.
Dated thin ɔond day of January 1805
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.

page_text: Improvements in the Production of Chilled Metal Castings.
I, EMIL PEIPERS, of 7, Frankfurter Strasse, Siegen, Westphalia, Manufacturer,
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 :-
This invention relates particularly to the chill casting of rolls for rolling mills,
and consists in providing the inner surface of the chill-mould with air ducts formed
by longitudinal grooves covered by a layer of baked loam, as hereafter described
with reference to the accompanying drawing, forming part of this Specification,
wherein Figure 1 is a vertical section of the complete mould ready for casting, and
Figure 2 is a cross-section of part thereof, drawn to a larger scale to shew the
grooves.
a is the chill mould, the bore or inner surface whereof has formed in it longitudinal
grooves & wherein cores formed by strings of common hemp, or equivalent material,
are temporarily inserted after which the chill-mould is lined with a thin layer c,
Figure 2, of loam or moulding material which may be composed of a moist mixture
of moulder's sand, river sand, and graphite. This coating fills up the grooves
except the part thereof occupied by the core strings; it must be smoothed down
evenly and must not be too thick (say about two millimetres) so that the chilling
effect of the chill-mould a on the metal of the casting shall not be materially
hindered or diminished. When this thin coating has become thoroughly air
dried, the strings of hemp are withdrawn from the grooves & and the coating is
baked by placing the chill-moulds in a core-oven of appropriate construction.
Then when the bottom case d, the chill-mould a, and the top case e, are fitted
together in the foundry pit i, and the parts f, g, h, of the runner connected, the
casting may take place, the spaces vacated by the strings in the grooves b
serving as air ducts.
By coating the surface of the chill-mould with a thicker layer than has been
hitherto usual (the chill-mould having previously only been washed with a solution
of graphite in water (black-wash)) the excessively sudden chilling of the casting
is obviated so that the skin of the casting is more tenacious and much less brittle
than heretofore.
The process is particularly advantageous for long chill-hardened rolls of large
diameter, such as are used in iron and steel manufacture, because the tension or
hardness of the metal is more evenly graduated towards the interior and there is
not therefore such an abrupt difference between the hardness of the skin and of the
body of the metal, so that the castings are not so liable to crack either in cooling or
during subsequent use.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that
what I claim is :-
Chill moulds having vertical air ducts formed substantially as described by
longitudinal grooves in the chill covered over with a smooth coating of moulding
material applied and baked as described.
Dated this 20th day of September 1895.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.