IMPROVEMENTS IN THE MANUFACTURE OF METAL TUBES
Year: 1884

page_text: I, JOSIAH PUMPHREY, of 160, Angelina Street Birmingham in the County of
Warwick Manufacturer do hereby declare the nature of my invention for
IMPROVEMENTS IN THE MANUFACTURE OF METAL TUBES, to be as follows:-
The objects of this Invention, which has especial reference to the manufacture
of metal tubes applicable for use in garden syringes and for other purposes, are to
avoid the necessity of the usual process of soldering the tubes which softens the
metal adjacent to the soldered edges causing the tube to leave its cylindrical form
and to attain other advantages hereinafter referred to.
In the manufacture or formation of the improved tubes, the sheet of metal to be
used is cut to the exact size required, and the side edges are each folded over to a
given distance in opposite directions and with an ordinary folder, one of the edges
is formed with a single fold, and the other is formed with a double fold, and the
folded edges are brought into such a position as to cause them to hook into each
other.
The tube thus roughly formed is pushed on to a mandril until it meets a collar
or set-off formed at the one end thereof, and which is made of a height.
corresponding with the thickness of the metal being used; and there is drawn
down on to the end of the partly formed tube and in contact with the set-off a
loose collar which securely holds the metal of the tube in place and prevents it
from rising over the set-off inside..
On the other end of the mandril there is placed a die or steel plate, through
which by means of an endless chain the mandril with the partly formed tube
outside is drawn, this process perfecting the formation of the tube and hardening
it therein.
The advantages of the improved formation of tube as compared with tubes as
ordinarily manufactured, are, that the hitherto necessary softening process of
soldering is not required, the tube is hardened and not softened in its formation,
the tube is produced of a truly cylindrical form, there is a considerable saving of
time as compared with the ordinary plan of hammering, every part of the material
cut up is used there being no parts cut away or held by pincers or plyers as in
ordinary mandril drawn tubes.

page_text: I JOSIAH PUMPHREY of N° 160 Angelina Street Birmingham in the County of
Warwick, Manufacturer do hereby declare the nature of my invention for
IMPROVEMENTS IN THE MANUFACTURE OF METAL TUBES and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
I cut the metal to the exact length and breadth required and with the tools
usually used, so bend the edges to be brought together that the return edge of one
Bide can be made to include the other return edge. I now insert a mandril of the
size of the interior of the tube required, furnished at the end further from the
point with a collar of or about the thickness of the metal of the tube, when
the metal has been forced up to this collar, I take a die so shaped as to draw
the folded edges close to the mandril, and bring it over the, metal, the fore-end
of the mandril is furnished with an eye and it is by that means attached to the
chain of a draw-bench, when the die is impeded by the poppets on the bench, the
back edge of the metal resting against the fixed collar, pushes the metal through
the die, if the thickness of metal, the size of the, die, and mandril be properly
arranged a tube is produced perfectly cylindrical, and water, and air-tight, without
the necessity of soldering, a process which always softens the metal, and for many
purposes, impairs its usefulness.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is the use of the collar on the mandril as the resisting point in the process
of drawing obviating the necessity of waste material involved by cutting the metal
first and then by bruising the metal afterwards by holding the same by pliers in
the ordinary manner.
Dabad thin nighth dow of NASAMA 1001