An Improvement in Drawing Metal Tubes or Tubular Bodies and in Apparatus therefor.
Year: 1889

page_text: Date of Application, 29th Jan., 1889
Complete Specification Left, 17th Oct., 1889-Accepted, 23rd Nov., 1889
PROVISIONAL SPECIFICATION.
An Improvement in Drawing Metal Tubes or Tubular Bodies and in
Apparatus therefor.
I, WILHELM LORENZ, of 44 Westendstrasse, of Karlsruhe, in the Grand Duchy of
Baden, German Empire, Engineer and Manufacturer, do hereby declare the nature
of this invention to be as follows:-
My invention has for its object the production of drawn metal tubes or tubular
bodies having variable thickness.
For this purpose an ordinary draw bench or press having a die A, Fig. 1 of the
accompanying drawings, of usual construction for tube drawing, is provided with a
conical or tapering mandril D, and into the die is inserted the tube B B to be operated
upon, this having been subject to a preliminary drawing process whereby its sides are
drawn to a uniform thickness, and provided with suitable means at one end such as a
welded head C as shewn, whereby it can be seized and drawn through the die.
The smallest diameter of the die corresponds to the external diameter to be imparted
to the tube. The tapering mandril D, introduced into the tube to the point where
this is acted upon by the die, is fixed to a spindle E which is provided with a screw
thread at its other end and screws through a nut F mounted in a rotatable manner on
the draw bench. This nut can either be turned by hand or automatically by gearing
or other suitable means at a speed depending upon the speed at which the tube is
drawn through the die. According as the nut is turned to the right or to the left,
the conical mandril D will be moved forward or backward in the tube, whereby, in
the first named case, the annular space between it and the die will be reduced, and
consequently the tube drawn through will become thinner, while in the latter case the
annular space will be increased, producing an increased thickness of the tube. By
this means it will be seen that the tube operated upon may be to made to increase or
decrease gradually in thickness from the one end to the other, as indicated at Fig. 2,
or the thickness may be made to alternately increase and decrease as indicated at
Fig. 3.
1000
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improvement in Drawing Metal Tubes or Tubular Bodies and in
Apparatus therefor.
I, WILHELM LORENZ, of 44 Westendstrasse, of Karlsruhe, in the Grand Duchy of
Baden, German Empire, Engineer and Manufacturer, 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 has for its object the production of drawn metal tubes or tubular
bodies having variable thickness as I will proceed to describe with reference to the
drawings accompanying my Provisional Specification.
An ordinary draw bench or press, having a die A, Fig. 1, of usual construction for
tube drawing, is provided with a conical or tapering mandril D, and into the die is
inserted the tube B B to be operated upon, this having been subject to a preliminary
drawing process whereby its sides are drawn to a uniform thickness, and provided
with suitable means at one end such as a welded head as shewn, whereby it can be
seized and drawn through the die.

page_text: The smallest diameter of the die corresponds to the external diameter to be imparted
to the tube. The tapering mandril D, introduced into the tube to the point where
this is acted upon by the die, is fixed to a spindle E which is provided with a screw
thread at its other end and screws through a nut F mounted in a rotatable manner on
the draw bench. This nut can either be turned by hand or automatically by gearing
or other suitable means at a speed depending upon the speed at which the tube is
drawn through the die. According as the nut is turned to the right or to the left, the
conical mandril D will be moved forward or backward in the tube, whereby, in the
first named case, the annular space between it and the die will be reduced and
consequently the tube drawn through will become thinner, while in the latter case the
annular space will be increased, producing an increased thickness of the tuhe. By
this means it will be seen that the tube operated upon may be made to increase or
decrease gradually in thickness from the one end to the other, as indicated at Fig. 2,
or the thickness may be made to alternately increase and decrease as indicated at
Fig. 3.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is
1. Producing drawn tubes or tubular bodies of varying thickness by causing
a mandril D of conical or tapering shape to be moved forward or backward within
the tube or tubular body while this is being drawn through the die A so as to
reduce or increase the annular space between the mandril and die, substantially as
herein described.
2. The use for the production of tapering tubes or tubular bodies of tapering
thickness in the manner set forth in the preceding claim, of a conical or tapering
mandril D mounted within the die A on a spindle E with screwed end passing through
a nut F mounted in the draw bench, so that by rotation of the nut, the spindle and
mandril can be moved backward and forward.
Dated this 17th day of October 1889.
ABEL & IMRAY,
Agents for the Applicant.