An Improved Process and Apparatus for the Manufacture of Explosives.
Year: 1896

page_text: Date of Application, 4th Feb., 1896-Accepted, 7th Mar., 1896
[Communicated from abroad by the Firm of FRIED. KRUPP GRUSONWERK, of
Magdeburg-Buckau, in the Empire of Germany, Manufacturers.]
An Improved Process and Apparatus for the Manufacture of
Explosives.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, 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 to a process and apparatus for the manufacture of tubular
or other threads or cords from a mass of explosive material previously operated
upon by rollers.
In the preparation of certain kinds of smokeless explosives, kneading by means
of sets of rollers, or roller-mills, has proved to be an advantageous and serviceable
operation, even in those cases where the explosive material is to be used in other
forms than that of flakes or thin pieces, or of blocks or cubes.
Now the object of this invention is to enable the desired form to be imparted to
the explosive material fed from the rollers in the form of a band, and the said
invention will be best understood by reference to the accompanying drawings which
represent, by way of example, a press, adapted to produce threads or cords of
explosive material by the improved method herein described.
In the said drawings
Figure 1 is a sectional elevation of the press the parts being in the position they
occupy just after the pressing operation has commenced.
Figure 2 is a vertical section of the pressing chamber, die and plunger the
chamber being filled with a roll of plastic material ready to be pressed.
The said press mainly consists of a suitably shaped pressure chamber a, into
which a plunger 6 is adapted to be forced. The plunger 6 is secured to a double-
acting plunger c, arranged to reciprocate vertically within a hydraulic cylinder d.
The said plunger b is hollow and carries at its lower end a die e, through which
the explosive mass or paste is forced in the condition of a thread or cord which
issues through an aperture provided in one side in the wall of the hollow
plunger. Below the chamber a, is arranged a second hydraulic cylinder g, of
smaller size than the cylinder d, and connected by a pipe g with the upper part.or
space of the said larger cylinder d, and having a piston or plunger h, which carries
a rod k. The rod k passes through the bottom of the chamber a, being made
tight at the joint by means of a stuffing-box or bush as shown. This rod kis
designed to accomplish a double purpose, that is to say, its upper end receives a
pin or mandrel whenever it is desired that the thread or cord produced should be
hollow or tubular, while at the same time the said rod forces the explosive material
in the chamber a towards the plunger 6, so as to expel any air that may be present
in such material.
The operation of the press is as follows: that is to say ;
The explosive paste, supplied from the rollers in the form or condition of a
band, is wound upon a rod or pin of wood or other suitable material less in diameter

page_text: than the rod k. The outer diameter of the roll or coil thus formed should be
such that it will fit the inner diameter of the chamber a. The roll, as soon as
formed, is placed in the said chamber a and while it is being so inserted into the
said chamber, the plunger b remains in its highest position and the rod k remains
at the extremity of its downward stroke. After the insertion of the coiled band
of explosive material into the chamber a, the plunger 6 is allowed to descend
as far as is necessary to enable it to rest upon the material to be pressed. The
water or other fluid acting as a pressure medium is at the same time admitted into
the cylinder g, whereby the piston h, and with it the rod k, are caused to rise.
The pointed end of the rod k is consequently driven into the body or mass of
explosive paste, thereby enlarging or expanding the central hole and compressing
the coiled material, the air confined between the several convolutions of the said
coiled material being thus displaced and caused to escape through the die e.
While the plunger & still remains stationary, the rod k continues to ascend, until
it completely fills the hollow space of the coil or roll of explosive material. By
this time the mandrel at the upper end of the said rod k, has taken up its proper
position relatively to the die e, and the cross-head of the lower plunger has risen
into contact with the shoulders of the rods m m, attached to the upper plunger c.
At this moment the compression of the explosive paste and the moulding of the
cord or thread will be commenced. Through the medium of the aforesaid rods m m
the lower plunger h, together with its rod k will be forced downwards by the upper
plunger c, in proportion as the plunger b is forced down in the chamber a, so that
the die e retains its position relatively to the rod k, the consequence being that the
explosive material is forced between the mandrel and die, whence it issues in the
form of a tubular cord through the lateral aperture f of the plunger b.
When it is desired to form the explosive cord otherwise than hollow or tubular
it is only necessary to dispense with the mandrel on the rod k, the end of which
being thus left blunt, as it were, in that case only rises to the bottom end of
the die.
When the forcing process is completed the rod k and plunger & with the die will
have descended to their lowest position in which position the said rod for the time
being remains, while the plunger, by the operation of the reversing gear, re-ascends
to its initial or upper position, leaving the orifice of the chamber a free to receive a
fresh charge of plastic explosive material.
Not only does the method of press-moulding hereinabove described enable the
material to be treated, or worked, directly as delivered from the roller mechanism,
but it also permits all the air confined in the body of the material to be got rid of,
without necessitating any preliminary forcing process. Therefore the product
finally obtained-riz. the explosive cord or thread-may be relied upon as being
homogeneous and free from air bubbles, the consistence or density, imparted to the
explosive material by the rollers, undergoing no diminution in consequence of the
change of form to which it is subjected in the press.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondents, I declare that what I claim is :-
1. A process or method of manufacturing tubular or other threads or cords of
explosive material from a pasty or plastic mass previously rolled in the form of a
band; the said process or method consisting in placing the coil of plastic material
in a chamber and compressing the same throughout its convolutions by forcing a
mandrel into the central or inner convolution, thereby displacing the air confined
between the convolutions, and forcing the material through a die substantially as
and for the purpose specified.
2. The chamber arranged substantially as described in combination with means
for applying pressure to the material therein and with a dic for imparting the
required form to the material issuing from the said chamber...

page_text: 3. The apparatus constructed substantially as described with reference to the
drawings and operating as set forth and for the purpose specified.
Dated this 4th day of February 1896.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.