Improvements in the Manufacture of Hollow or Solid Elongated Projectiles and in the Machinery and Tools Employed therein.
Year: 1890

page_text: Date of Application, 6th May, 1890
Complete Specification Left, 6th Feb., 1891-Accepted, 7th Mar.,
1891
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Hollow or Solid Elongated
Projectiles and in the Machinery and Tools Employed therein.
We, Tuomas DAVAGE the Younger, of Saville Street East, Manager, and SETH
TAYLOR, of Ellesmere Road, Engineer, both of Sheffield, in the County of York,
do hereby declare the nature of our invention to be as follows:-
This invention relates in the first place to a method of, and apparatus for, rolling
the aforesaid projectiles; and secondly to improvements in forging same.
In carrying out the first part of our invention we propose to use a pair of disc
rollers fixed upon the ends of two horizontal shafts, in line one with the other, the
discs being face to face, and driven so that they revolve in opposite directions.
The faces of the dises are turned, cast, or otherwise forned with a concentric
circular projection thereon, each side of the ridge of the projection being of a corre-
sponding radius to that of the point of the required projectile, and these ridges are
exactly opposite each other.
The said discs and shafts are carried in suitable bearings, and are arranged so
that they can be adjusted in distance, one or both being made to slide to and fro.
We then take a cylindrical bar of steel which has previously been cut to a given
length, sufficient to make two or more projectiles and place it between the two discs
which have been separated to receive it.
The rotation of the discs in contrary directions, and the pressure as they are
made to approach each other, act together upon the heated bar of steel and form
the pointed conical ends or portions of two projectiles. A similar bar of heated
steel may be inserted at the opposite side of the discs, and a corresponding effect
produced at one and the same time if desirable.
We then take the partly formed projectile and drill, press, or otherwise form a
hole in the base, of a suitable size and depth.
A mandril is then inserted, and the projectile forced between a pair of disc rollers
somewhat similar to those before described by hydraulic or other pressure, the
mandril revolving with the projectile, which is thus reduced and elongated upon the
mandril to its proper dimensions and form. This operation also may be duplicated
on the opposite side of the discs, and a stop (or stops) may be fixed or arranged, so
that when the said projectile is reduced to the desired proportions by reversing, the
hydraulic ram, the mandril can be withdrawn.
According to the second part of our invention which relates to forging hollow
elongated projectile. we take a bar of steel, and either press or forge it in suitable
dies, into a blunt conical form the base of which is larger than the dimension of
the required shell; we then form a hole in the base by punching or any other
means.
We prepare a mandril having one end of the proper dimensions of the hole
required in the shell, and having a collar at a suitable distance from the point of
nandril.
We insert the point of the mandril into the recess already formed in the base of
the conical forging, and place the said forging between a pair of dies approximating
to the required shape of the shell, and which will also receive the collar upon the
mandril. The operation of the dies which are usually fixed in a steam hammer
reduces the said conical forging in diameter, and elongates it upon the mandril,
which is prevented by the collar from being forced back.
This latter operation may be repeated in several pairs of dies, or top and bottom

page_text: tools until it is brought to its finished dimensions or thereabouts, allowing a small
margin for trueing up by a grinder.
Dated the 5th day of May 1890.
ROBT. F. DRURY, Fel. Inst. P.A.,
Bank Buildings, George Street. Sheffield, Agent for Applicants,

page_text: or bed of a steam hammer or press, the hammer head or top die G being cupped to
a shape approximating to the form of the projectile. The operation of the top die
drives the drift into the drilled hole enlarging it and expanding the shell as shown
at H Fig. 3; by this arrangement of a vertical drift, and a descending outside-die
the forging is carried up and down and thereby prevented from becoming fast upon
the drift, it is also very easily released from the top die due to its contraction while
cooling.
The finishing rolls Fig. 4, are also discs revolving in contrary directions, and
have their faces brought to a point I, at the centre, and of such a curve that when
the centre points are brought together the sectional outline of the space from the
point I, to the periphery is the forin of the desired projectile.
The forging or blank H constructed as hereinbefore described is supported upon
a mandril M carried by the end of a hydraulic ram R, or other similar mechanical
appliance capable of giving the required forward pressure, and of revolving with
the forging, as it is rotated by the rolls.
The disc-rolls are drawn apart and the enlarged forging inserted between them,
and as the rolls are forced together, the forging is compressed upon the drift or
mandrill M, and rolled between the curved faces until it is brought to the exact
size and configuration; it may be finished or dressed by any further process if
desired.
Instead of finishing the forging between the last mentioned pair of disc-rolls, we
may use a pair of top and bottom dies as shown in Fig. 6, these dies are constructed
to enclose the mandril M as well as the forging; the recess or matrix for the
forging is of the exact finished size, and a recess is made to receive the head or
shoulder of the mandril M, by which it is prevented receding from its position, when.
therefore the dies are in operation (as in a steam hammer) the hot steel is com-
pressed and forced backwards until the recess, matrix, or mould is completely filled,
any excess finding its way through a small opening at the point.
If it is desired to forge the projectiles without the use of the disc-rolls, we forge
a blank in tools such as are well known, and after drilling it as before described,
it is passed under the tools shown in Fig. 3, and finished in the tools above described
and shown in Fig. 6.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is or may be carried into practice, we declare
that what we claim is :-
:-
1-In the manufacture of hollow or solid elongated projectiles, the process of
rolling the material between disc-rollers having a concentric projection or ring
formed on their working faces, and capable of being moved towards and from each
other while revolving in opposite directions, substantially as hereinbefore described
and illustrated.
2-In the manufacture of hollow or solid elongated projectiles the process of
rolling the partly finished projectiles between a pair of disc-rollers having on their
faces a projecting centre point curving back to the face, of the desired form, to give
the finished form or configuration to the projectile, when the points are brought
together, substantially as herein before described and shown in Figs. 4 & 5.
3-In the manufacture of hollow elongated projectiles, the method or process of
enlarging and forming the chamber or interior, by driving or pressing the base of
the projectile over a vertically fixed punch or drift; the projectile being carried by
a recess or matrix in the hammer face or top die G, substantially as herein before
described and as shown in Fig. 3.
4-In the manufacture of hollow elongated projectiles, and in finishing the inside
and outside of same; a pair of top and bottom dies having a recess of suitable size
to finish the outside of the projectile, and a second recess to receive the collar or
other enlargement on the mandril M, by which the drift is prevented from being
driven back by the extension of the metal under operation, and a uniform thickness

page_text: of metal is always obtained between the point and the end of chamber, substantially
as hereinbefore described and as shown in Fig. 6.
Dated this 4th day of February 1891.
ROBT. F. DRURY, Fel. Inst. P.A.,
Bank Buildings, George Street, Sheffield, Agent for Applicants.