IMPROVEMENTS IN AND IN CONNECTION WITH MOULDS USED IN CASTING STEEL AND OTHER METALS
Year: 1878

page_text: LETTERS PATENT to John Thomson King, of Liverpool, in the County of
Lancaster, Patent Agent, for the Invention of "IMPROVEMENTS IN AND IN
CONNECTION WITH MOULDS USED IN CASTING STEEL AND OTHER METALS." A
communication from abroad by Aaron J. Nellis, of Pittsburgh, Pennsylvania,
United States of America.
Sealed the 20th September 1878, and dated the 28th March 1878.
PROVISIONAL SPECIFICATION left by the said John Thomson King at
the Office of the Commissioners of Patents on the 28th March 1878.
JOHN THOMSON KING, of Liverpool, in the County of Lancaster, Patent Agent.
"IMPROVEMENTS IN AND IN CONNECTION WITH MOULDS USED IN CASTING STEEL AND
OTHER METALS." [A communication from abroad by Aaron J. Nellis, of Pittsburgh,
Pennsylvania, United States of America.]
•
My Invention, which relates to the construction of moulds and to the material
employed in forming moulds, is generally applicable in casting metals, but more
especially steel, where saving of time and the perfection of the castings are im-
portant.
The object of the first part of the Invention is to so construct moulds that they
may be durable, readily repaired, easily kept in order, and shall permit of the con-
tracting of castings so as to obtain perfect articles.
The
For the above purpose
construct a mould partly of metal and partly of sand,
ashes, loam, or any other suitable materials, such as are used to form cores.
metal and the core or other like material employed to form a mould are arranged
in alternate sections, care being taken that wherever pockets or recesses occur the
metal and core or like material should meet so as to ensure that the casting shall
free itself when contracting.
The object of the second part of the Invention is to provide a material for
forming moulds or cores of such a nature that the moulds and cores formed may be
employed as soon as made, no drying being required, and that perfect castings,
1

page_text: devoid of blow holes, may be obtained. For this purpose I employ sand or other
suitable material in combination with a highly combustible and readily ignitible
fluid, such as benzine or like light hydrocarbon, turpentine, or alcohol. The com-
bustible liquid takes the place of the water usually employed to cause the particles
of sand or other material to bind or adhere together, and may if desired contain or
be mixed with some adhesive substance, such as sugar, flour, or the like. The saud
preferred is a clean sharp sand, ordinary moulders' sand not being desirable, though
capable of use.
I have found in practice that a material having all the necessary and desirable
qualities for making moulds or cores may consist of sharp sand, one half bushel ;
brown sugar, three pounds; rye flour, three pounds; benzine or its equivalent, two
gallons; to which, if desired, may be added fire-clay, one quart.
When the material for the mould or core is mixed with a highly inflammable
liquid, as specified, the mould or core may be used immediately after being made,
thus avoiding the delay incident to the drying of moulds when water is used. The
possibility of using the moulds and cores at once permits of the reduction of the
number kept on hand when metal section moulds are used.
In a mould prepared in accordance with this part of my Invention, the com-
bustion which takes place at the time of casting insures a vent for the gases and
frees the mould of air; thus a sharp clean casting, devoid of blow holes, is
produced.
In cases where the mould or core is used more than once, or when they have
been made a long time, it is advantageous to moisten or damp the mould or core
with the inflammable liquid.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Thomson King in the Great Seal Patent Office on the
27th September 1878.
JOHN THOMSON KING, of Liverpool, in the County of Lancaster, Patent Agent.
"IMPROVEMENTS IN AND IN CONNECTION WITH MOULDS USED IN CASTING STEEL AND
OTHER METALS." A communication from abroad by Aaron J. Nellis, of Pittsburgh,
Pennsylvania, United States of America.
My Invention relates to the construction of moulds and to the material employed
for forming moulds. It is generally applicable in casting all metals where saving
of time and the perfection of the castings are important, but is especially adapted
to the casting of cast steel.
For the purposes of this description the Invention may be treated under two
divisions: First, the mechanical construction of moulds, wherein not only the
special composition subject of the second division may be used, but any other well-
known and suitable core material; and secondly, compositions especially adapted to
the formation of cores, inoulds, matrices, &c., for casting cast steel.
Fig. 1 is a perspective view of a mould embodying the Invention set forth in the
first division, one side of said mould being removed to show the interior; Fig. 2 is
a sectional view on the line <> ---x, Fig. J.
Like letters refer to like parts wherever they occur.
The objections to sand moulds are the lack of durability, and the difficulty of
obtaining perfect moulds, and also the necessity of drying the sand thoroughly,
which requires considerable time, especially if the mould is large. The object of
this head of the Invention is to obtain a mould readily repaired and kept in order,
one which will have the advantages of both the sand and metal mould, without the
disadvantages of either, and will permit the contracting of the casting so as to
obtain perfect articles.
In the Drawing is represented a mould partly of iron and partly of sand. The
larger portions of the mould A, A, or sides are formed from iron in the usual
manner, and the ends or intervals a, a, are filled with sand cores to complete the
nould. The sections or cores a, a, are made from sand, ashes, loam, &c., or any
other suitable core material, and are shaped to the requirements of the position
they occupy in a mould, being dried and prepared in the manner and by the means
well known in the art. In a mould of such or similar form, two cores or sides a, a,
being formed of sand, will give sufficient surface for the escape of gases, and will
permit the casting to contract; therefore the remaining section a' may be made of
either iron or sand, as preferred. A mould of any desired form may be thus made
in alternate sections of metal and sand, the rule to be observed being that where-
ever corners or pockets occur in the inould the sand and metal should meet, giving
one material froin which the casting can free itself in contracting, there being no
tendency of the casting to adhere to plain surfaces, but only in corners or pockets,
and where it is apt to cut in pouring. The metallic sections are generally formed
separately, and connected to the core sections of the inould by pins, bolts, &c.
The advantages of a mould constructed in accordance with this part of my In-
vention are, first, that it is rapidly and readily repaired; and secondly, that it
insures a good casting.
Under the second division my Invention embraces the material employed. It
consists in mixing the sand or coro material for the formation of either sand moulds,
cores, or sections of moulds with a highly combustible and readily ignitable fluid,
which will burn at the time of casting, whereby a perfect casting and one devoid
of "blows" is obtained.
In the present method of mixing sand moulds, cores, &c., water or like liquid is
commonly employed, necessitating the thorough drying of the mould before it can
be used, which consumes from thirty hours to ten days, depending on the size and

page_text: shape of the mould. To overcome this delay is one object of the present In-
vention.
In other instances the mould has been composed of sections of metal with inter-
posed sections of core material, and in such cases where the cores were not specially
prepared (as set forth in the first division of this Specification), but were built into
the mould, it necessitated the keeping on hand of a large number of moulds, in
order that the compound mould could be subjected to suitable means for drying the
sand section. Another object of this part of my Invention is therefore to reduce
the number of moulds required.
It is well known that neither with iron moulds, moulds composed in part of iron
with sand sections, or composed entirely of sand, is it possible to obtain a fair per-
centage of perfect cast steel castings where the pattern is of irregular form, or the
pouring hole of the mould is of limited size. With either or all of the moulds
specified there is a tendency to " blow," owing either to imperfect vent for the gases,
or from other cause. The main object therefore of this head of the Invention is to
insure a perfect vent or combustion of gases, &c., as the case may be, and as a
result a perfect casting.
The material which composes the mould or cores, as the case may be, is mixed
with a highly inflammable and combustible liquid, or one that will ignite at the
time of casting, for which purpose benzine or like light hydrocarbon is preferable,
both owing to its cost and the readiness with which it is obtained, but turpentine,
alcohol, and other combustible fluids have been employed and found to answer
well. As many of the combustible liquids are not sufficiently binding of themselves
some of the well-known adhesive substances may be employed therewith, such as
sugar, flour, &c., and the sand preferred is a clean sharp sand, ordinary moulders'
sand not being desirable, though capable of use.
For purposes of this Specification the following proportions may be stated as
giving a satisfactory mass, either for cores or flask moulds, though I do not intend
or expect to be limited thereby-Sharp sand, one half bushel; brown sugar, three
pounds; rye flour, three pounds; benzine or its equivalent, two gallons, to which,
if desired, may be added fire-clay, one quart.
Where the material for the core, sand mould, or matrix is mixed with a highly
inflammable combustible fluid, as specified, the mould may be used immediately,
thus avoiding the delay incident to the drying of moulds, and the possibility of
using the moulds at once permits of the reduction in the number kept on hand
where metal section moulds are used. To this extent the Invention is useful for all
classes of casting.
In casting cast steel into irregular form with small pouring holes, as for instance,
in the casting of plowshares, &c., in the moulds prepared in the ordinary way, the
invariable blowing renders the casting imperfect, unless a highly carburized steel is
employed, which necessitates subsequent treatment of the casting to render it fitted
to the purposes intended.
In a mould prepared in accordance with my Invention the combustion which
takes place at the time of casting insures a vent for the gases, frees the mould of
air, and results in a perfect casting, devoid of blows, which especially adapts iny In-
vention to the production of cast steel castings.
Repeated experiments with castings produced in moulds wherein the sand, &c.,
was mixed with a highly inflammable combustible liquid, as specified, have shown
that the castings can be readily drawn and worked under the hammer in the sainc
manner as tool steel, and that they possess a toughness much in excess of any other
castings of like character known.
In cases where the mould is used more than once it is desirable to moisten or
sponge the matrix, cores, &c., with benzine or equivalent liquid, as after the com-
bustion of the liquid employed in forming the mixture the casting is liable to be
less perfect. The same result is attendant upon the use of moulds long made, and
from which the liquid has evaporated, in both of which latter cases the mould will
act more like an ordinary well dried sand mould.

page_text: Having thus described my Invention and its advantages, what I claim and desire
to secure by Letters Patent is,―
1. A mould composed of metallic sections and intermediate separate and
detachable sections formed of core material, substantially as and for the purpose
specified.
2. A mould composed of metallic sections and intermediate separate and detach-
able sections formed of core material, with suitable means for at once connecting
the metallic and supporting the core sections, substantially as and for the purpose
specified.
3. Sand moulds, cores, and matrices for casting metal, composed of sand, with or
without binding or adhesive materials, and of benzine or its equivalent highly com-
bustible and readily ignitible liquid, substantially as specified.
In witness whereof, I, the said John Thomson King, have hereunto set my
hand and seal, the Twenty-fifth day of September, in the year of our Lord
One thousand eight hundred and seventy-eight
W. B. JOHNSON,
4, Clayton Sq., Witness.
Liverpool.
J. T. KING. (L.S.)