IMPROVEMENTS IN THE CONSTRUCTION OF MACHINERY OR APPARATUS FOR THE MANUFACTURE OF LEAD OR OTHER METAL PIPES
Year: 1879

page_text: "
LETTERS PATENT to Samuel Gratrix, of Manchester, in the County of Lan-
caster, for the Invention of IMPROVEMENTS IN THE CONSTRUCTION OF
MACHINERY OR APPARATUS FOR THE MANUFACTURE OF LEAD OR OTHER
METAL PIPES"
Sealed the 2nd May 1879, and dated the 13th February 1879.
PROVISIONAL SPECIFICATION left by the said Samuel Gratrix at the Office
of the Commissioners of Patents on the 13th February 1879.
SAMUEL GRATRIX, of Manchester, in the County of Lancaster.
IN THE CONSTRUCTION OF MACHINERY OR APPARATUS FOR THE MANUFACTURE OF
LEAD OR OTHER METAL PIPES."
"IMPROVEMENTS
This Invention relates to the manufacture of pipes from lead or other soft metal
or alloy by forcing the same through a die when in an almost fluid state.
Hitherto the central core for forming the interior of the pipe has been fixed by
means of a bridge extending across the die, and the metal in passing this bridge
became necessarily divided, and was re-united on the other side by pressure in
passing through the die.
Hence there was always a seam or joint down each side of the pipe, which, not being
actually soldered but only squeezed together whilst the metal was in a soft state, was
more or less liable to open or give way when submitted to internal pressure. An
attempt has been made to remedy this defect by attaching a long core to the head
of the ram, but owing to the requisite length and thinness of the core it was found
to be almost impossible to keep it in the true centre of the die, and hence the pipe
became uneven in thickness, added to which the last length of pipe could not be
drawn off the core, but had to be melted off and worked up again.
My improvement consists in fixing in the interior of the cylinder a permanent
steel pillar of about (say) four to six times the diameter of the core. The upper or free
end of this pillar reaches up very nearly to the die at the upper end of the cylinder.
The lower end is attached by means of a cross bar to the lower end of the
cylinder.
°
Into the upper end of the steel pillar is screwed a short core which passes into
the centre of the die. The die is fixed at the top of the cylinder in the usual

page_text: manner by means of a gland, and both the die and the core can be easily changed
for making pipes of different diameters.
The ram is made with a ring at the top, which fits exactly the space between the
steel pillar and the interior of the cylinder. The bottom of the ram is solid, and
-the-body-thereof_is_formed with a long slot, through which the cross-bar (which
supports the steel pillar) passes.
its
When the hydraulic pressure is applied to the lower end of the ram it rises, and
upper end slides up the fixed-pillar, forcing the metál before it, the metal being
then-in-the-form-of-a-tube filling_the_space between the cylinder and the pillar.
The top of the pillar is rounded or conical, and in it is screwed the core, and hence-
as the metal is pressed-forward-it-still-retains-its-tubular_form, but in passing
between the core and the die it becomes reduced in diameter, and lengthened out in
La proportionate degree, and thus a tube of the required:diameter is produced without
any seam or joint whatever.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Samuel Gratrix in the Great Seal Patent Office on the 9th August
1879.
SAMUEL GRATRIX, of Manchester, in the County of Lancaster.
"IMPROVEMENTS
IN THE CONSTRUCTION OF MACHINERY OR APPARATUS FOR THE MANUFACTURE OF
LEAD OR OTHER METAL PIPES."
This Invention relates to the manufacture of pipes from lead or other soft metal
or alloy by forcing the same through a die when in an almost fluid state.
Hitherto the central core for forming the interior of the pipe.has been fixed by
means of a bridge extending across the die, and the metal in passing this bridge
became necessarily divided, and was re-united on the other side by pressure in
passing through the die. Here there was always a seam or joint down each side of
the pipe which, not being actually soldered but only squeezed together whilst the
metal was in a soft state, was more or less liable to open or give way when sub-
mitted to internal pressure.
An attempt has been made to remedy this defect by attaching a long core to the
head of the ram, but owing to the requisite length and thinness of the core it was
found to be almost impossible to keep it in the true centre of the die, and hence the
pipe became uneven in thickness, added to which the last length of pipe could not
be drawn off the core, but had to be melted off and worked up again.
My Invention will be readily understood on reference to the Drawings hereto
annexed and the following explanation thereof:-
Fig. 1 is a vertical section of a hydraulic machine, with my improved apparatus
applied thereto; and Fig. 2, a similar view taken transversely or at right angles to
the former.
My improvement consists in fixing in the interior of the cylinder a, a, a permanent
steel pillar b, b, of about (say) four to six times the diameter of the core, see also
detached views, Figs. 3 and 4. The upper or free end of this pillar reaches up very
nearly to the die c, c, at the upper end of the cylinder a, a. The lower end is
attached by means of a cross bar d, d, to the lower end of the cylinder a, a.
Into the upper end of the steel pillar is screwed a short core e, e, which passes
into the centre of the die c, c. The die c, c, is fixed at the top of the cylinder a, a,
in the usual manner by means of a gland f, f, and both the die c and the core e can
be easily changed for making pipes of different diameters. The ram g, g, is made
with a ring g* at the top, which fits exactly the space between the steel pillar b, b,
and the interior of the cylinder a, a.
The bottom of the ram is solid, and the body thereof is formed with a long slot
h, h, (Fig. 2), through which the cross bar d, d, (which supports the steel pillar b, b₁)
passes.
When the hydraulic pressure is applied to the lower end of the ram g, g, it rises
and its upper end g* slides up the fixed pillar b, b, forcing the metal before it, the
metal being then in the form of a tube, filling the space i, i, between the cylinder a, a,
and the pillar b, b.
The top of the pillar is rounded or conical, and in it is screwed the core e, e, and
hence as the metal is pressed forward it still retains its tubular form, but in passing
between the core e and the die c it becomes reduced in diameter and lengthened out in
a proportionate degree, and thus a tube of the required diameter is produced without
any seam or joint whatever.
Having now described the nature and object of my said Invention, together with
the manner in which the same is to be or may be performed or carried into practical
effect, I wish it to be understood that I claim as my Invention, the improvements
in the construction of machinery or apparatus for the manufacture of lead or other
metal pipes, as hereinbefore described, and illustrated by the Drawing annexed, and

page_text: more especially I claim the use of the strong steel pillar, into the free end of which
a small core is screwed or otherwise fixed, its lower end being provided with a cross
bar working in a vertical slot in the ram.
In witness whereof, I, the said Samuel Gratrix, have hereunto set my hand
-and-seal,-this.Seventh-day of August, in the year of our Lord One thousand
eight hundred and seventy nine.