Improvements in Tube Drawing and Mechaniam relating thereto.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Tube Drawing and Mechaniam relating thereto.
HENRY JAMES BROOKES, of Westbourne, Smethwick, in the County of Stafford,
Cycle Manufacturer, HENRY PAITMAN TRUEMAN, of 51, Havelock Road, Hands-
worth, in the County of Stafford, Engineer, and GEORGE EDWIN MINTON, of
363, Rotton Park Road, Bumingham, in the County of Warwick, Engineer, do
hereby declare the nature of this invention to be as follows;-
-
The object of this invention is to provide means whereby metal tubes may be
for med having the interior diameter varying at and for any desued portion of a
tube length, the exterior diameter of the said tube remaining approximately
unaltered This invention enables tubes to be manufactured having walls varying
in thickness, so as to produce what 18 known in the trade as inside taper, single
butt or double butt tubes
This invention consists in arranging the usual die and mandrill plug of a tube
drawing bench so that the relative position of the die and the mandrill plug may
be altered longitudinally with regard to each other during the passage of a tube
through the die and over the plug The die may be stationary, and the mandiill
plug may be moved longitudinally during the passage of the tube through the die
and over the plug The movement of the die or of the plug is effected by suitable
mechanism, timed to move the die or to move the mandiill plug at predetermined
intervals
One convenient method of canying this invention into effect consists in con-
necting the mandrill plug at the "tail end of the draw bench to a bell crank
lever This said bell crank lever 18 or may be operated by wedges passing under
one arm of the said level, the other end being fixed to the mandi ill plug in such
a manner that the plug is by means of the said bell ciank lever caused to bo
withdiawn o to be thrust forward into the die during the passage of a tube over
the plug and through the die as before described The said wedges for operating
the bell crank are or may be fixed to a rod connected to the drawing chain or the
cariage in such a manner that the said wedges are passed under the bell crank
at stated intervals
When
When the mandrill plug is standing within the die, the tube 18 or may be
reduced in the thickness of its walls, but when the mandrill plug 18 withdrawn
from the die, the walls of the tube remain approximately its original thickness.
The plug end of the mandrill is preferably barrel shaped or double coned
the walls of the tube are required to be of varying thickness the end of the mandrill
18 formed with plugs of vaiving diameter Any desired portion of the plug may
be caused to stand within the operating face of the die and so the walls of the
resulting tube will be of a thickness proportionate to the relative outside diameter
of the plug and the internal diameter of the die The mechanism for moving the
mandrill plug or the die may be connected to the main gearing wheels in com-
bination with cams, toggles, levers, endless screws or other equivalents for pro-
071

page_text: ducing a longitudinal movement between die and plug at predetermined intervals
as herein before described.
Dated this 23rd day of December 1898
HENRY JAMES BROOKES.
HENRY PATTMAN TRUEMAN.
GEORGE EDWIN MINTON
Improvements in Tube Drawing and Mechanism relating thereto.
HENRY JAMES BROOKES, of Westbourne, Smethwick, in the County of Stafford,
Cycle Manufacturer, HENRY PATTMAN TRUEMAN, of 51, Havelock Road, Hands-
worth, in the County of Stafford, Engineer, and GroRGE EDWIN MINTON, of
363, Rotton Park Road, Birmingham, in the County of Warwick, Engineer, 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:-
The object of this invention is to provide means whereby metal tubes may be
formed having the interior diameter varying at and for any desued portion of a
tube length, the exterior diameter of the said tube remaining approximately
unaltered. This invention enables tubes to be manufactured having walls varying
in thickness, so as to produce what is known in the trade as inside taper, single
butt or double butt tubes
This invention consists in alianging the usual die and mandrill plug of a tube
diawing bench, so that the relative position of the die and the mandrill plug may
be altered longitudinally with regard to each other during the passage of a tube
through the die and over the plug The die may be stationary, and the mandrill
plug may be moved longitudinally, on the mandrill plug may be stationary and
the die may be moved longitudinally during the passage of the tube through the
die and over the plug The movement of the die, or of the plug, is effected by
suitable mechanisin, timed to move the die or to move the mandiill plug at pre-
determined intervals
One convenient method of canying this invention into effect consists in con-
necting the mandill plug at the tail end" of the diaw bench to a bell ciank
lever This said bell cıank lever is or may be operated by wedges passing under
one arm of the said lever, the other end being fixed to the mandrill plug in such
a manner that the plug is by means of the said bell crank lever caused to be
withdrawn, or to be thrust forward into the die during the passage of a tube over
the plug and through the die as before described. The said wedges for operating
the bell crank are o may be fixed to 1od connected to the drawing chain on the
carriage in such a manner that the said wedges are passed under the bell ciank
at stated intervals.
When
When the mandiill plug is standing within the die, the tube is or may be
reduced in the thickness of its walls, but when the mandrill plug is withdrawn
from the die the walls of the tube remain approximately its original thickness.
The plug end of the mandrill is preferably bairel shaped or double coned
the walls of the tube are required to be of varying thicknesses, the end of the man-
dill is formed with plugs of varying diameter Any desued portion of the plug may
be caused to stand within the operating face of the die and so the walls of the
resulting tube will be of a thickness proportionate to the relative outside diameter
of the plug and the internal diameter of the die The mechanism for moving the
mandrill plug or the die may be connected to the main gearing wheels in com-

page_text: bination with cams, toggles, levers, endless screws or other equivalents for pro-
ducing a longitudinal movement between die and plug at predetermined intervals
as hereinbefore described.
In order that this invention may be more readily understood, we have illus-
trated examples thereof in the annexed drawings, and will proceed to describe
the said invention with reference to the said drawings.
Figs. 1 and 2 are diagrams representing the tube diawing die arranged to remain
stationary while the plug is moved longitudinally during the passage of a tube
through the die.
Figs. 3 and 4 are diagrams representing the plug in a stationary position, while
the die is moved longitudinally during the passage of a tube through the same.
Fig. 5 represents an ordinary tube drawing bench fitted with means for auto-
matically moving the plug longitudinally during the passage of a tube through the
die.
Fig. 6 represents a tube having walls of approximately the same thickness
throughout its length Fig. 7 represents the same tube after being passed through
the apparatus herein described, and after being treated according to this invention.
Fig. 8 represents a long length of tube after being passed through apparatus
constructed, arranged and operated as described in connection with Fig. 5.
Similar letters and figures refer to similar parts of the apparatus throughout the
drawings.
A is the fixed abutment of an ordinary diaw bench.
01
B 18 the die which determines the outside diameter of any tube drawn through
the same,
C 18 the mandill plug which determines the interior diameter of any tube
diawn over the same.
D, Figs 3 and 4 is a moving abutment placed between the fixed abutment A
and the die B of a draw-bench E Figs 3 and 4 1s a sliding plate moving between
the fixed abutment A and the moving abutment 1)
The toggles e, e, have one end resting in the plate E and then other ends rest
in the moving abutment D Let the plug C of Figs. 3 and 4 be prevented from
moving longitudinally, and let the die B of Fig 3 stand over the plug C as shown
Then, when the tube F is drawn through the die B and over the mandrill plug C
the walls of the said tube F will be reduced in thickness, the die B determining
the outer and the mandrill plug C the inner diameter Let the sliding plate
of Fig. 3 be moved upwards into the position shown in Fig 4 Then the toggles e, e,
will allow the abutment D and the die B to move tongitudinally away from over
the mandrill plug C Then the outer diameter of the tube F will be reduced to
the diameter of the die B as in Fig. 3, but the walls of the tube will not be reduced
in thickness because the plug C no longer occupies the same position within the
die B as in Fig 3. The sliding plate E can be operated by any convenient
mechanism
Figs. 1 and 2 illustrate the passing of a tube through the die B which remains
in a fixed position against the abutment A In this case the tube F starts with
the plug C standing within the die B, but at a predetermined moment the plug C
is withdrawn partially or wholly from within the die as shown in Fig 2 The
result of this operation 18 clearly shown in Figs. 6 and 7 Fig 6 shows a tube
formed with a neck f, the remainder of the tube being of any desired equal
diameter both inside and outside from end to end Fig 7 shows the same tube
after treatment as above described It will be clearly seen, that the walls of the
tube are thinner in the midway position and each end is approximately of the same
thickness as the original tube shown in Fig 6 The tube Fig 6 is elongated
during the operation herein described, which converts the tube into the form
shown in Fig. 7.
Fig 5 represents one convenient method of arranging an ordinary chain draw
bench for use according to this invention. A is the fixed abutment, B 18 the
fixed die, C is the moving mandrill plug. This mandrill C at its rear end is

page_text: screwed into an extension of the same I, I K3 K4 are lock nuts to limit the
longitudinal movement of I, I. This said extension is passed through a hollow
sleeve J, which is screwed on the outside and is furnished with 'locked nuts K¹, K'
The locked nut K₁ 18 connected to the bell oiank lever I. The nuts K 1 and K
are locked by a set screw not shewn on the drawings. When this said bell crank lever
1s moved, the mandrill plug C is also moved in and out of the die B. The bell
ciank lever L 18 moved, when the wedges M are diawn under its free end by means
of the bar N The bar № 18 connected to a clutch box O. The clutch box 0 18
connected by means of the bar 1', with the draw bench carriage G, this said cai-
age G being connected with the moving chain of the draw bench in the usual
way The shackle is connected to the nut h and by engaging lock nuts KJ
on I, I, seives to prevent any end motion of I, I, through sleeve J when the bell
crank is moving the mandill plug in and out of the die B. The lever R is con-
nected with the bolt T by means of the chain and wheel S. When the bolt T 18
aised by the lover R, the bolt T lifts the bell crank away from and clear of the
wedges Af, and also by means of the bolt U, 1aises the shackle Q. The mandrill
plug C can now be moved back for the purpose of threading a fresh tube upon the
mandrill plug C. The wedges M are clamped at any desired distance apart on
the bai N The wedges in passing under the bell crank Liaise the free end and
withdraw the mandrill plug hom the die When the wedge passes from under the
lever, the weights V cause the lever L to fall and the mandrill plug is again
thrust into the die B. In place of the weights V suitable springs can be used to
cause the lever L to fall.
It will now be seen that a long length of tube such as shown in Fig 8 can be
produced by the apparatus herein described, the thick portions being formed when
the plug C is not standing inside the die B, and the thinner portions being formed
when the plug C 18 placed within the die The draw bench car-
11age G takes hold of the tube F by neck f. This said carriage G
also draws the wedges M under the lever L through the clutch box 0
and the bars N and P. Should the carnage G fail to release itself from the chain
when the tube F has passed through the die B, the clutch box Oieleases the bar P
which then allows the,calage r to be disconnected from the chain at any con-
venient time The end of the mandrill plug C is shown enlarged at Fig. 1 from
which illustration it will be seen that it is smaller in diameter at the ends than
in the middle, this shape having been found by experiment to be very favourable
for the purpose of this, invention.
We do not confine ourselves to the exact kind of draw bench herein described,
nor do we confine ourselves to the bell crank and wedge method of altering the
elative longitudinal position of the die as in Figs. 3 and 4, or of the mandrill as
in Figs 1, 2 and 5 during the drawing of a tube, but have described and illus-
tiated the same as one convenient method of carrying this invention into effect.
It is obvious that mechanism could be arranged to operate from the main gearing.
In some
cases it might be convenient to use independent steam, hydraulic,
pneumatic or electric motors, arranged to operate the die or to operate the plug
at predetermined intervals herein described.
Having now particularly described and ascertained the nature of our said
invention and the manner in which it is to be performed, we declare that
what we claim is:-
1 The method or process of producing tubes having walls varying in thickness,
by means of the combination of a die and a plug, arranged so as to be moved
longitudinally with regard to each other during the passage of a tube through the
die as and for the purpose herein described and illustrated.
2. The combination of a die and a plug, arranged so as to be moved longi-
tudinally with regard to each other during the passage of a tube through the die,
as and for the purpose herein described and illustrated.
3. The plug having ends smaller in diameter than the centre portion, in com-

page_text: bination with a die arranged to alter their longitudinal position with regard to
each other, during the passage of a tube through the die, as and for the purpose
herein described and illustrated.
4 The combination and arrangement of a fixed plug together with a die which
can be moved longitudinally upon the plug, substantially as described and illus-
trated in Figs. 3 and 4 of the drawings
5. The moving abutment D in combination with a fixed abutment A, arranged
to operate substantially as illustrated and described in Figs 3 and 4 of the
drawing.
6 The combination and arrangement of a fixed die, together with a plug which
can be moved longitudinally with regard to the die, during the passage of a tube
through the die, substantially as described and illustrated in Figs. 1 and 2 of the
drawing
7 The moving plug C in combination with the fixed die B, together with means
for moving the plug at predetermined intervals substantially as and for the
purpose as herein described and illustrated in Figs 1, 2 and 5
8 The combination and arrangement of the various devices for converting exist-
ing draw benches for use according to this invention, consisting of the tail
abutment H, the mandill extension I, the sleeve J, the nuts K1, K2, the ball clank
lever L, the wedges M the bars N and P, the clutch box 0, the distance piece
shackle Q, the lever R, the wheel and chain S, the bolt T, the screw bolt U. the
weights V. all arranged and operating substantially as herein described and illus-
trated in Fig 5 of the drawings.
9 The moving die B, in combination with the fixed plug C together with means
for moving the die at predetermined intervals substantially as and for the purpose
herein described and illustrated in Figs 3 and 4.
+
10 The combination and arrangement of the devices for moving the die B con-
sisting of the moving abutment D, the sliding plate E, the toggles e, e, the fixed
abutment of an ordinary draw bench A, in combination with any convenient
mechanism for operating the die B and the moving abutment D at predetermined
intervals, substantially as and for the purpose herein described and illustrated
Dated this 22nd day of September 1899
HENRY JAMES BROOKES.
HENRY PATTMAN TRUEMAN.
GEORGE EDWIN MINTON.