Improvements in Apparatus for Making Tubes or Cylinders of Steel or like Metal.
Year: 1893

page_text: Date of Application, 17th Feb., 1893
Complete Specification Left, 15th Dec., 1893-Accepted, 20th Jan., 1894
TRUVIDIONAL DIUINICATION.
Improvements in Apparatus for Making Tubes or Cylinders of Steel
or like Metal.
We, WILLIAM CRAWFORD and JAMES CRAWFORD of 49, Arlington Street,
Glasgow, in the County of Lanark, North Britain, Tinsmiths, do hereby declare
the nature of this invention to be as follows, that is to say :-
Our said invention has for its object to make tubes or cylinders of steel or like
metal in an improved manner.
In carrying out our invention we form a tube by elongating a short tube having
one end closed and which is hereinafter termed a pot, such elongation being effected
by means of hydraulic apparatus, the pot or tube being drawn through a die
constituted by a scries of rollers, and heat being applied during the operation.
The pot is cast or otherwise formed with a clutch projection on its closed end which
projection is taken hold of by the drawing apparatus. A circular series of claw
levers fitted to a ring engage with the clutch projection of the pot, with their lower
ends, their upper ends engaging with the top edge of a central opening in the
drawing head. The claw levers can be attached by means of their ring to a crane
chain for transferring the pot from a furnace to the machine. The drawhead may
be moved by an overhead hydraulic cylinder or by three or more hydraulic
cylinders arranged round the base of the machine with their rams extending
upwards to the drawhead.
"
The die rollers are fitted in recesses made round about a central aperture in a
fixed entablature, each roller being centered between the cheeks of a holder which
is fitted into a recess in a manner to allow of it turning down to withdraw the
roller a short distance from its acting position, so as to become free from the pot or
tube. The die rollers are raised into acting position by a ring which rises under
the holders at the commencement of an operation. Or the die-roller holders may
be moved into acting position by wedges or other suitable mechanism.
In the bedframe of the machine there is a short hydraulic cylinder which acts
upwards on a disk having extending up from it a central spindle at the upper end
of which is fixed a small disk to act as an inside die or mandril within the pot or
tube. After a fresh pot has been placed in position for being drawn the inside die
is by the action of the bottom hydraulic cylinder raised up into its acting position,
opposite to the narrowest part between the die rollers. At the same time the
movement into position of the die rollers is effected by means of rods extending
from the ring acting directly on the roller holders down to a lower ring acted on
by the disk moved by the bottom hydraulic cylinder. The disk acted on by the
bottom hydraulic cylinder is arranged so that it can be turned by toothed gearing,
in order to turn the central spindle and inside die, with the view of diminishing
frictional resistance to the elongating action by turning the pot or tube whilst it is
being drawn up between the die rollers. The central spindle is made tubular and
water is forced up it to the upper side of the inside die to keep that die comparatively.
cool and also to cool the part of the tube which is above and has passed the die
rollers. A return passage for the water is provided by placing a small pipe inside
of the tubular spindle; and this spindle is kept sufficiently cool partly by the water
passing through it, and partly by a covering of nonconducting material which may
or may not be enclosed in a pipe.
The heat is applied to the pot or tube whilst being operated on, by gas burned

page_text: in an annular space between the pot or tube and an outer cylindrical shell lined
with firebrick or other refractory inaterial. The gas is admitted at the lower part
of the annular space through regulated inlets, the air for its combustion being
admitted through other regulated inlets. A thickened end may be left on the tube
by moving the die rollers a little outwards before drawing the lower end of the
tube through them.
After a tube has been drawn of a certain diameter through one set of die rollers
the whole or any part of it may be subsequently reduced in diameter by drawing
it through a set of die rollers having a smaller central opening, with the view of
thickening or strengthening the tube or for other purposes.
Dated this Sixteenth day of February 1893.
EDMUND HUNT,
Applicants' Agent.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Making Tubes or Cylinders of Steel
or like Metal.
We, WILLIAM CRAWFORD and JAMES CRAWFORD, of 49 Arlington Street,
now in the County of the City of Glasgow, North Britain, Tinsmiths, 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, that is to say :-
Our said invention has for its object to make tubes or cylinders of steel or like
metal in an improved manner.
In carrying out our invention we form a tube by elongating a short tube having
one end closed and which is hereinafter termed a pot, such elongation being effected
by means of hydraulic apparatus, the pot or tube being drawn through a die
constituted by a series of rollers, and heat being applied during the operation.
And in order that our said invention and the manner of performing the same
may be properly understood we hereunto append a sheet of explanatory drawings,
to be hereinafter referred to, and showing our improved apparatus for making tubes
or cylinders of steel or like metal.
Figure 1, of the drawings is a vertical section of our improved apparatus.
Figure 2, is a vertical section of the pot.
Figure 3, is a horizontal section of the entablature of the press, and other parts.
Figure 4, is a plan of a part of the bottom framing.
In these drawings the same reference letters and numerals are used to mark the
same or like parts wherever they are repeated.
The pot, A, is cast or otherwise formed with a clutch projection, A 1, on its
closed end, which projection is taken hold of by the drawing apparatus. A circular
series of claw levers, B, fitted to a ring, B 1, engage with the clutch projection, A 1,
of the pot, A, with their lower ends, their upper ends engaging with the top
edge of a central opening, C, in the drawing head, D. Two opposite claw levers, B,
have jointed to them an eye bolt or bar, B2, by means of which they can be
attached to a crane for transferring the pot, A, from a furnace to the machine.
The drawhead, D, may be moved by an. overhead hydraulic cylinder, but we
prefer to employ three (or more) hydraulic cylinders, E, arranged round the base
of the machine with their rams, E 1, extending upwards and being bolted to the
drawhead.
The die rollers, F, are fitted in recesses made round about a central aperture, G,
in a fixed entablature, G 1, each roller being centered between the cheeks of a
holder, F 1, which is fitted into a recess in a manner to allow of its turning down
to withdraw the roller a short distance from its acting position, so as to become

page_text: free from the pot, A, or tube, A 2, (which latter is shown in full lines in Figure 1,
as after having undergone one drawing operation and in dotted lines as after having
undergone two drawing operations). The die rollers, F, are raised into acting
position by a ring, H, which rises under the roller holders, F 1, at the commence-
ment of an operation, being actuated by mechanism hereinafter explained. Or if
desired the die-roller holders, F 1, might be moved into acting position by wedges
or other suitable mechanism.
In the bottom framing, J, J 3, of the machine there is a short hydraulic
cylinder, J 1, which acts by its ram, J 2, upwards on a disk, K, having extending
up from it a central spindle, K 1, at the upper end of which is fixed a small disk, L,
to act as an inside die or mandril within the pot, A, or tube, A. 2. After a fresh pot, A,
has been placed in position for being drawn, the inside die, L, is by the action of
the bottom hydraulic cylinder, J 1, raised up into its acting position opposite to
the narrowest part between the die rollers, F. At the same time the movement
into position of the die rollers, F, is effected by means of rods, M, extending from
the ring, H, acting directly on the roller holders, F 1, down to a lower ring, M 1,
acted on by the disk, K, moved by the bottom hydraulic cylinder, J 1. The
disk, K, acted on by the bottom hydraulic cylinder, J1, is arranged so that it can
be turned by a pinion, N, loose on a vertical shaft, N 1, gearing with teeth, K 2, on
the periphery of the disk, the pinion, N, being driven in any convenient way, not
shown. The disk, K, is turned in order to turn the central spindle, K 1; and inside
die, L, with the view of diminishing frictional resistance to the elongating action by
turning the pot, A, or tube, A 2, whilst it is being drawn up between the die rollers, F.
In grooves or recesses in the upper side of the disk, K, there are anti-friction
balls, P, which when the disk, K, is raised fit into counterpart grooves, P 1, P 2, in the
ring, M 1, and in the upper part, J 3, of the bottom framing, the later groove, P 2,
limiting the upward travel of the disk, and the balls being provided to enable the
disk, to be easily turned when bearing hard up. The central spindle, K 1, is made
tubular and water is forced up it to the upper side of the inside die, L, to keep that
die comparatively cool and also to cool the part of the tube, A 2, which is above
and has passed the die rollers, F. A return passage is provided by placing a small
pipe, R, inside of the tubular spindle, K 1; and this spindle is kept cool partly by
the water passing through it and partly by a covering of non-conducting material, S,
encircling the spindle.
The heat is applied to the pot, A, or tube, A 2, whilst being operated on, by gas
burned in an annular space between the pot or tube and an outer cylindrical
shell, T, lined with firebrick, or other refractory material. The gas is led by a
pipe, V, encircling the outer cylindrical shell, T, and is admitted into the annular
space through a series of inlets, T 1, which are also made large enough to admit air
for the combustion of the gas.
A thickened end may be left on the tube by moving the die rollers, F, a little
outwards before drawing the lower end through them.
After a tube (A 2) has been drawn of a certain diameter through one set of die
rollers (F) the whole or any part of it may be subsequently reduced in diameter by
drawing it through a set of die rollers having a smaller central opening with the
view of thickening or strengthening the tube or for other purposes.
Non-rotating dies made in two or more segments may be used instead of the die
rollers.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is:-
1. Constructing and combining or arranging the parts of apparatus for making
tubes or cylinders of steel or like metal in the improved manner substantially as
hereinbefore described and shown in the accompanying drawings.
2. In apparatus for forming a tube or cylinder, the combining of hydraulic

page_text: appliances to draw a pot through a die consisting of rotating. or non-rotating parts
with an internal rotating disk and with direct heating apparatus substantially as
herein before described.
Dated this Fourteenth day of December 1893 ·
EDMUND HUNT,
Applicants' Agent.