Improvements in the Manufacture of Hollow Projectiles or Shells for Ordnance.
Year: 1893

page_text: Date of Application, 7th Mar., 1893
Complete Specification Left, 30th Dec., 1893-Accepted, 3rd Feb., 1894
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Hollow Projectiles or Shells
for Ordnance.
I, ROBERT Low, of 11 Queen Victoria Street, in the City of London,
Consulting Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements in the manufacture of hollow projectiles
or shells for ordnance.
The object of my said invention is to produce from wrought iron or steel (with
or without nickel or chromium) containing from 0.3% to 0.5% of carbon and not
more than 0.3% of manganese, an improved armour-piercing hollow projectile of a
high quality, the metal of which is specially treated according to this invention,
to make it hard at the exterior of the projectile, and tough at the interior thereof.
By the said treatment the penetrative power of the said projectile is greatly
increased and the possibility of the occurrence of breakage or of deformation is
diminished.
By my invention I am enabled to obtain a high-class projectile at a moderate
cost, for I operate upon a material less expensive than that which is usually
employed for like articles, and I avoid the use of expensive and sometimes
uncertain processes, such as have hitherto been commonly employed in the
manufacture, for instance, of armour-piercing shells from high class chrome steel
or from steel containing a considerable percentage of carbon.
According to one method of carrying my said invention into practice which I
will now set forth by way of example, I take a hollow projectile of wrought iron
or medium steel and bore and turn it to the proper dimensions, and fill the core or
powder-chamber with oxide of iron or with manganese, or with a mixture of both
these substances. In some cases when the shell is of steel I fill it with sand, and
when it is of wrought iron I use carbon for filling the core. The projectile thus
filled is placed point downwards on a bed of carbonaceous material in a suitable
fire proof cylinder, wherein it is also surrounded with carbonaceous material
packed into close contact with its exterior. The said cylinder is then closed, and
placed in a furnace in which it and its contents are raised to a suitable temperature,
say about 3000° Fahrenheit, and maintained thereat for such a period as will
suffice to enable the carbonaceous material to carburize the outer portions thereof,
until said portions contain about 2% of carbon. This high degree of carburization
will render the shell self-hardening in the air, thus avoiding the necessity for
plunging it into water or oil for the purposes of hardening, which would be
attended with some risk.
The oxide of iron and manganese in the core or powder-chamber will effect the
toughening of the inner portions of the projectile.
I can treat by a method such as is hereinbefore described, more than one shell
at a time, in a single cylinder or other suitable chamber, and I can substitute for
the oxide of iron or manganese, any other material which, used in like manner,
will produce a similar toughening effect upon the interior of the shell.
To complete the hardening process, when the shell in its cylinder is removed
from the furnace, I allow it to cool down until it reaches a cherry red heat, then I
lift it from its cylinder and allow it to cool in the atmosphere so as to impart the
desired hardness to the shell.
Or according to another method of carrying my said invention into practice, I
make a mould of carbonaceous material into which I place a core, made of sheet

page_text: iron and filled with oxide of iron or manganese; I then pour into the mould molten
steel, and as soon as the steel is set I place the mould and its contents in a suitable
furnace heated to the required temperature, and allow it to remain therein until
the shell has been carburized to the desired degree by contact with the
carbonaceous mould. At the same time the core effects the toughening of the
inner walls of the shell. By this process I make a good armour piercing shell
without the expense of forging.
In some cases I use a mould the lower part of which is composed of carbonaceous
material and the upper part of which is composed of steel-moulders, composition or
other refractory material, and so produce a shell with a hard head and tough body.
When the shells are cold I place them in a suitable grinding lathe fitted with a
radial rest, and I polish the outer surface thereof, for example, with an emery
wheel.
Dated this 7th day of March 1802
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Hollow Projectiles or Shells
for Ordnance.
I, ROBERT Low, of 11 Queen Victoria Street, in the City of London,
Consulting Engineer, 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:―
My invention relates to improvements in the manufacture of hollow projectiles
or shells for ordnance.
The object of my said invention is to produce from cast steel (with or without
nickel or chromium) containing from 0.5 per cent. to 0.8 per cent. of carbon and not
more than 0.3 per cent. of manganese, an improved armour-piercing hollow projectile
of a high quality, the metal of which is specially treated according to this invention,
to make it hard at the exterior of the projectile, and tough at the interior thereof.
By such treatment the penetrative power of the said projectile is greatly increased
and the possibility of the occurrence of breakage or of deformation is diminished.
By my invention I am enabled to obtain a high-class projectile at a moderate
cost, as I employ a material less expensive than that which is usually employed for
like articles, and I avoid the use of expensive and in some cases uncertain processes,
such as have hitherto been commonly employed in the manufacture, for instance, of
armour-piercing shells from high class chrome steel or from steel containing a
considerable percentage of carbon.
In the accompanying drawings,
Figure I is a central longitudinal section of a mould employed for the manufacture
of shells in accordance with my invention, and
Figure 2 indicates a slightly modified construction thereof.
In carrying my said invention into practice I provide a mould A, Figure 1, of the
proper shape, composed of compressed carbonaceous material contained preferably in
a fire-proof cylinder B. Into the said mould I place a core D consisting of oxide of iron
or manganese or a mixture of both these substances enclosed in an iron or steel
casing C. E is the core spindle, by means of which the core is suspended in the
mould. G is a block of steel-moulders' composition for closing the upper end of
the mould. I pour into the mould, the molten steel to form the shell, and as soon
as the steel is set I place the mould and its contents in a suitable furnace heated
to the required temperature say about 3000° Fahrenheit and allow it to remain
therein until the outer portions of the shell have been carburized to the desired

page_text: degree (say until they contain 2 per cent. of carbon) by contact with the car-
bonaceous mould. While the hardening of the exterior of the shell is proceeding,
the interior thereof is undergoing a toughening process by contact with the core.
By this process I make a good armour-piercing shell without the expense of
forging.
In some cases I use a mould the lower part of which, viz.: that which encloses
the point of the shell is composed of carbonaceous material and the upper part of
which is composed of steel-moulders' composition or other refractory material, and so
produce a shell with a hard head and tough body. Such a mould is indicated in
Figure 2, F representing the steel-moulders' composition.
To complete the hardening process, the shell after having cooled down to a
cherry red, is lifted out of the mould and allowed to cool down in the atmosphere,
the air imparting to it the required hardness. This hardening in the air is rendered
possible by reason of the high degree of carburization to which the outer surface of
the shell has been subjected.
When the shell is cold I place it in a suitable grinding lathe fitted with a radial
rest and I polish the outer surface thereof by any suitable means, for example, by
means of an emery wheel.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The manufacture of a steel shell by casting the same in a carbonaceous mould,
for the purpose specified.
2. The combination, with such mould, of a core, consisting of oxide of iron, or
manganese or a mixture of both these substances, enclosed in an iron or steel
casing, substantially as described, for the purpose specified.
3. The manufacture of a steel shell by casting the same in a carbonaceous mould
and then hardening its exterior surface by cooling in the atmosphere without
contact with a liquid.
4. The modification of my invention wherein the steel shell is cast in a mould
composed partly of carbonaceous material, and partly of steel-moulders' composition
or other refractory material, substantially as, and for the purpose, specified.
5. A hollow steel projectile or shell produced as herein described.
Dated this 30th day of December 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.