"NEW OR IMPROVED MACHINERY FOR WELDING TUBES
Year: 1881

page_text: LETTERS PATENT to Andrew Stewart and James Stewart, both of the Firm of
Andrew and James Stewart, of Coatbridge, in the County of Lanark, North
Britain, and John Wotherspoon, Manager to the said Firm, for an Invention
PROVISIONAL SPECIFICATION left by the said Andrew Stewart, James
Stewart, and John Wotherspoon at the Office of the Commissioners of Patents
on the 10th February 1881.
ANDREW STEWART and JAMES STEWART, both of the Firm of Andrew and
James Stewart, of Coatbridge, in the County of Lanark, North Britain, and
JOHN WOTHERSPOON, Manager to the said Firm. "NEW OR IMPROVED MACHINERY
FOR WELDING TUBES."
This Invention, which relates to new or improved machinery for welding tubes,
has reference more especially to tubes of large diameter, such as those used for
boiler flues or the barrels of boilers or other such like tubular bodies constructed of
iron or steel.
The mechanism constituting this Invention is adapted both for welding the
longitudinal seams or joints of such tubes, as well as transverse joints occurring in
the welding of two lengths of tube together.
The mechanism for welding the longitudinal joints or seams in tubes consists of
a strong head-stock fitted so as to slide in a bed piece. In the outer end of the
overhanging arm of this head-stock is carried a hydraulic cylinder and ram, in the
lower part of the ram there being arranged a roll which is pressed by the requisite
force obtained from the ram against or upon the outer side of the joint which has
to be welded. Below this overhanging arm of the head-stock, and projecting out
under it, is a strong horn, in the outer end of which, and immediately under the
roll carried by the aforesaid hydraulic ram, is another roll, against which, during
the welding operation, the inner side of the joint to be welded is pressed. To a
vertical horn on the bed piece is attached the piston rod of a hydraulic cylinder
and piston, this hydraulic cylinder and piston being provided for the purpose of

page_text: pulling back or pushing forward the sliding head-stock and its attachments. On
being pulled or pushed this action causes the rolls when in contact with the heated
part of the joint to be rotated, and thereby to weld the joint, stops being provided
for the purpose of preventing the tube from moving endwise. Or the head-stock
may be stationary, in which case the tube is moved endwise during the welding
action, either by the rolls, or by a hydraulic cylinder, as hereinafter described. In
the case of being drawn backwards and forwards between and by the action of the
rolls themselves, the rolls may be slowly rotated either by motive power mechanism,
or by a hand wheel of sufficient diameter, and as they are rotated they press jupon
the joint, and unite the parts which have been previously brought to a welding
heat, the rotating action of the rolls at the same time drawing the tube between
them lengthwise. In the case of moving the tube to be welded lengthwise by the
action of a hydraulic piston and cylinder, it is temporarily coupled to the tube, and
the tube thereby pulled and pushed alternately in opposite directions, thereby
causing the rotation of the welding rolls. The portion of the tube to be welded is
heated by a coke fire or a gas fire, or other suitable heater, placed either at the side
or below the apparatus, and when the required length of it, for example, a foot or
more, has been brought to the welding heat, it is turned round upon the horn so as
to bring the heated portion of the joint between the welding rolls.
In place of the arrangements hereinbefore described, the welding rolls may be
carried in the ends of arms or levers united together by a pin joint, and so arranged
that the distance apart of the rolls, and the pressure exercised by them, is regulated
by a hydraulic cylinder and ram, or by the equivalent thereof acting upon the
levers with any required degree of intensity.
In the apparatus for welding lengths of tube together by transverse joints, the
rolls in the hydraulic ram and in the horn respectively are placed in a position at
right angles to that herein before described with reference to the welding of
longitudinal joints or seams, and in this case when rotated for the purpose of
welding, they carry round the tube on its axis, and thereby form a transverse
weld.
It is to be understood that in all the forms of apparatus herein before described,
the equivalents of a hydraulic press for producing the requisite pressure on the
welding rolls may be substituted for the hydraulic press; and it is also to be
understood that the lap for the joints is previously prepared or shaped for the
purpose of producing a proper weld, and the requisite thickness of metal at the
joint after the weld has been made.
The said apparatus may be made stationary or portable.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Andrew Stewart, James Stewart, and John Wotherspoon in the
Great Seal Patent Office on the 10th August 1881.
ANDREW STEWART and JAMES STEWART, both of the Firm of Andrew and
James Stewart, of Coatbridge, in the County of Lanark, North Britain, and
JOHN WOTHERSPOON, Manager to the said Firm. "NEW OR IMPROVED MACHINERY
FOR WELDING TUBES."
Our said Invention relates to new or improved machinery for welding tubes, and
has reference more especially to tubes of large diameter, such as those used for
boiler flues or the barrels of boilers or other such like tubular bodies constructed of
iron or steel.
The mechanism constituting our said Invention is adapted both for welding the
longitudinal seams or joints of such tubes as well as transverse joints occurring in
the welding of two lengths of tube together.
Figure 1 of the accompanying Drawings represents in side elevation partly in
section, and Figure 2 in end elevation partly in section machinery constructed
according to our said Invention for welding the longitudinal joints or seams in
tubes. It consists of a strong head stock A fitted so as to slide in a bed piece B.
In the outer end of the overhanging arm of this headstock A is carried a hydraulic
cylinder a provided with a ram b, in the lower part of which ram there is arranged
a roll C, which is pressed by the requisite force obtained from the ram b against or
upon the outer side of the joint which has to be welded. Below the said over-
hanging arm of the head-stock A, and projecting out under it, is a strong horn D,
in the outer end of which, and immediately under the roll C carried by the aforesaid
hydraulic ram b, is another roll E, against which, during the welding operation, the
inner side of the joint to be welded is pressed. The rolls C and E have respectively
concave and convex peripheries corresponding respectively to the exterior and
interior of the tube to be welded, the said rolls being replaceable by rolls of
different curves for different diameters of tubes. To a vertical horn G, on the bed-
piece, is attached the piston rod g of a hydraulic cylinder g² and piston g³, the
said hydraulic cylinder and piston being provided for the purpose of pulling back
or pushing forward the sliding headstock A and its attachments. On being pulled
or pushed this action causes the rolls C and E when in contact with the beated part
of the joint to be rotated, and thereby to weld the joint, a stop or stops being
provided for the purpose of, preventing the tube from moving end wise. This stop,
as shewn in the Drawing, consists of the piece h, projecting into the path of the
tube and carried by a screwed rod h³ running in a screw box in the horn G, the
said screw being rotated by gearing wheels h³, h, driven by hand or other suitable
means so as to bring the stop h into proper position to stop the tube when the
proper length has been welded. The tube being welded is marked I in the
Drawing. The small piston and cylinder b² are provided to lift the roll C when
required. The head stock A may, if preferred, be stationary, in which case the
tube being welded is moved endwise during the welding action either by the rolls
or by a hydraulic cylinder, as hereinafter described. In the case of being drawn
backwards and forwards between and by the action of the rolls themselves, the
rolls may be slowly rotated either by motive power mechanism or by a hand
wheel of sufficient diameter, and as they are rotated they press upon the joint and
unite the parts which have been previously brought to a welding heat, the rotating
action of the rolls at the same time drawing the tube between them lengthwise.
Figure 3 represents a modified form of the machinery for moving the tube to be

page_text: welded lengthwise by the action of a hydraulic piston and cylinder K. The rod k
of the said piston is temporarily coupled to the tube to be welded, and the said
tube is thereby pulled and pushed alternately in opposite directions, thereby causing
the rotation of the welding rolls C and E. The portion of the tube to be welded
is heated by a coke fire, or a gas fire, or other suitable heater, placed either at the
side or below the apparatus, and when the required length of it, for example a foot
or more, has been brought to the welding heat, it is turned round upon the horn so
as to bring the heated portion of the joint between the welding rolls. Figure 4
shews a suitable form of gripper for the end of the rod k of the cylinder K for
grasping the tube being welded.
In place of the arrangements hereinbefore described the welding rolls may be
carried in the ends of arms or levers united together by a pin joint, and so arranged
that the distance apart of the rolls and the pressure exercised by them is regulated
by a hydraulic cylinder and ram, or by the equivalent thereof acting upon the.
levers with any required degree of intensity; Figure 5 illustrates this arrangement.
The arms or levers and m respectively carry the rolls C and E, the said arms
being jointed by the pin joint n, and having a hydraulic cylinder p between their
opposite ends for giving the requisite welding pressure between the rolls.
In the apparatus for welding lengths of tube together by transverse joints the
roll C in the hydraulic ram and the roll E in the horn respectively are placed in
a position at right angles to that hereinbefore described and shewn in the Drawings
with reference to the welding of longitudinal joints or seams, and in this case when
rotated for the purpose of welding they carry round the tube on its axis, and
thereby form a transverse weld; Figure 6 illustrates this arrangement. The rolls
C and E will in this case be of course formed with fat peripheries, and one or both
of them will be arranged to be rotated. In the Drawing motion of rotation is
shewn as being transmitted to the upper roll C through the shaft c² driven by any
suitable motive power.
It is to be understood that in all the forms of apparatus herein before described
the equivalents of a hydraulic press for producing the requisite pressure on the
welding rolls may be substituted for the hydraulic press; and it is also to be
understood that the lap for the joints is previously prepared or shaped for the
purpose of producing a proper weld and the requisite thickness of metal at the
joint after the weld has been made.
The apparatus may be stationary or portable.
Having now described and particularly ascertained the nature of our said
Invention, and the system, mode, or manner in or under which the same is or
may be used or practically carried into effect, we would observe in conclusion that
we wish it to be understood that we do not limit ourselves to the precise details
herein before described and illustrated in the accompanying Drawings, as the same
may be varied without departing from the nature of our said Invention; but what
we consider to be novel and original, and therefore claim as the Invention secured
to us by the herein before in part recited Letters Patent is,-
First. The machinery or apparatus for welding tubes or parts or lengths of tubes
together hereinbefore described under various modifications, wherein the essential
feature is the causing of the part of the tube to be welded to be passed or to pass
between rolls respectively bearing with the requisite pressure upon the interior
and exterior of the tube, essentially as hereinbefore described with reference to the
accompanying Drawings.
Second. The machinery or apparatus for welding tubes, constructed or arranged
essentially as herein before described and illustrated in Figures 1 and 2 of the
accompanying Drawings.
Third. The machinery or apparatus for welding tubes, constructed or arranged
essentially as hereinbefore described and illustrated in Figure 3 of the accompanying
Drawings.
Fourth. The machinery or apparatus for welding tubes, constructed or arranged

page_text: essentially as herein before described and illustrated in Figure 5 of the accompanying
Drawings.
Fifth. The machinery or apparatus for transverse welding, or the welding of
lengths of tubes or parts of tubes together, constructed or arranged essentially
as hereinbefore described with reference to Figure 6 of the accompanying
Drawings.
In witness whereof, I, the said Andrew Stewart, have hereunto set my hand
and seal, this Ninth day of August, in the year of our Lord One thousand
eight hundred and eighty one.
ANDREW STEWART. (L.S.)