Improvements in Manufacturing Wrought-iron Gas-pipes, and in Apparatus Employed in their Manufacture.
Year: 1898

page_text: Date of Application, 20th Aug., 1898-Accepted, 5th Nov., 1898
COMPLETE SPECIFICATION,
Improvements in Manufacturing Wrought-iron Gas-pipes, and in
Apparatus Employed in their Manufacture.
CARL TWER, of Eschweiler, Rhenish Prussia, Germany, Work-manager, 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 hitherto known welded tubes, gas-pipes and the like show at their welding
seam or shut a but joint and the strip or sheet-iron to be manufactured to a gas-
pipe or to the like was obliged, to be completely finished to a pipe, to pass three
times at least different bells, and that, once, to be bent into the shape of a tube and
twice to be welded at its joint.
Now, my invention relates to improvements in bells for manufacturing wrought-
iron gas-pipes the welding-seam or shut of which can be formed by two sharpened
edges, but at an angle of 45 degrees, in which funnel or bell a rotating-roller, being
arranged to pass through the wall of the bell to the inner surface thereof, operates
in conjunction with an elastic kernel amidst the interior of the bell; and the
objects of my improvement are, first, to provide a once passing of the strip through
the bell, to be manufactured into a gas-pipe or other tube and the edges of which
are sharpened; second to provide means for turning the elastic mandrel at the
proper moment into the bell and turning it out of the bell after having worked;
third, to afford facilities for the proper adjustment of the welding roller or rollers
penetrating the wall of the bell-die; and finally, to provide means for centering
the clastic mandrel within the bell-die so as to exactly locate its circular surface
always at the proper point of welding the strip of iron or skelp.
I attain these objects by the mechanism illustrated in the accompanying draw-
ings, in which
Fig. 1 is a top-view of the bell-die seen from its small end and provided with
rollers and elastic mandrel;
Fig. 2 is the side-view of the two parted bell with roller; the elastic mandrel,
the lever of which is broken, being turned out of the bell;
Fig. 3 is the front-view of the bell, the elastic mandrel being let down in its
lever and shown by dotted lines and points when it is turned out of the bell;
Fig. 4 shows one half bell with the mandrel located at the proper point when
the tube is welded, and finally,
Fig. 5 shows some details representing an other locating of the mandrel in
its lever.
Similar letters refer to similar parts throughout the several views.
The bell-die consists of two parts TT, that are joint one to another by means of
small screw-bolts s put through the eyes o. When the said two parts are joint one
to another, the so formed bell-die shows an aperture O arranged in its wall in order
to allow the elastic mandrel K to be turned, if required, out of the interior of
the bell.

page_text: At the small end of the bell-die its wall is provided at the place where the
sharpened seams of the iron strip put one to another, with apertures arranged on
opposite sides. Through each of those apertures enters to the inner surface of the
bell a pulley or roller R the axles of each of which are supported by two cheeks L.
The circuit of the said rollers corresponds to the inner surface of the bell-die. The
cheeks L can be made integral with the bell-die or can be manufactured separately
and fixed to the bell-die.
The bearings for the studs a of the pulleys R are arranged to be displaced in
slitst of the cheeks L and can be pressed by means of set screws u to the inner
surface of the bell-die.
=
At the one side of the bell die, the cheeks Lare lengthened and bear on a cross-
bolt a bent turning-lever h in the under extremity of which that is formed into
an eye, is arranged the shaft S of the elastic mandrel K.
The elastic mandrel shows at the place where the rollers R enter into the interior
of the bell die and where the seams of the iron strip are to be welded into a tube,
a circular circuit the diameter of which corresponds with the width in the clear of
the tube to be manufactured so that between the inner surface of the bell die and
the circuit of the mandrel the tube of a certain thickness can pass.
Below that circular circuit the mandrel has a conical shape in order to easily
have the iron strip entered into the bell die and put it around the circular circuit
of the mandrel; and above the circular circuit the mandrel has a conical shape too
as to not prevent the welded tube from being easily drawn out of the bell.
The mandrel K partly is cut in two parts in its middle in order to make it
elastic and to prevent a rupture of the bell-die or of its details.
At the under extremity the mandrel is provided with a long shaft S that is
secured in the eye A of the lever h, so that the mandrel must take, when the bell-
die operates, the position located' exactly betweens the rollers R.
The shaft S of the mandrel K can be secured in the eye A of the lever h by
means of a splint i (Fig. 4). When this splint is taken off, the mandrel can be
moved towards the large end of the bell-die, the shaft S passing through the eye A,
so that the mandrel has the position shown in Fig. 3. Hereafter I can turn the
mandrel out of the bell-die, by moving the lever h; the mandrel K passes through
the opening O in the wall of the bell-die.
But it is not absolutely necessary to move the mandrel towards the large end of
the bell in order to turn it out of the same. The under extremity of the shaft S
can be provided with a square b that is arranged in the squared eye A of the lever h.
(Fig. 5.) This eye however in this case is conical so that the upper extremity
of the eye, turned to the small end of the bell, has a greater space, than the under
extremity. The said square of the shaft S is provided with a small screw-bolt b₁,
by means of which the shaft is secured in the eye A of the lever h by a collar c
and a nut c₁, but in such a way that the shaft S and of course with it the mandrel K
can balance a little in the bell, the shaft S being able to oscillate in the eye A.
To avoid the fricture of the mandrel in the interiour of the tube intended to be
welded, I can, as shown in Fig. 1, hollow the mandrel from above and arrange
a small guiding roller r at the place of contact between the mandrel and the
tube to be welded, that is before the pulley R. Overthemore I can locate such a
guiding roller at the opposite side too. The wall of the hollow mandrel must be
cut-or intersected in order to be elastic for the purpose already mentioned.
The skelp or strip of iron of which the tube will be welded is signified by the
reference letter B; (Figs. 1 and 4); the dotted lines shown at the inside of the
half bell (Fig. 4) represent the way that the seams of the skelp must pursue when
the skelp is softly bent, and the letter G signifies the welded tube coming out of
the small end of the bell-die.
Now I may be permitted, in order that my invention may be more fully under-
stood, to describe the manner of operation of the apparatus.
The strip of iron or skelp, the seams of which are sharpened, in order to have a
greater welding space, and which can be, if required, blunt, is welded in the

page_text: sponding to the inner surface of said tubes, the mandrel being conical above and
under the said circular circuit and being partly cut or intersected and provided
with a shaft to be secured in a turning lever, essentially as set forth and for the
purpose specified..
5°). In a bell-die for welding metal tubes, an elastic mandrel that is hollowed
from above, guiding rollers, the axles of which are mounted in the wall of the said
hollowed mandrel, the said wall being partly intersected, essentially as described
and for the purpose specified.
JOSEPH MÖHLIG,
Agent for Applicant, Aix-la-Chapelle, Germany.
JOSEPH MÖHLIG,
Agent for Applicant, Aix-la-Chapelle, Germany.

page_text: common way with a guiding bolt and will be drawn out of the muffle or small
furnace located before the large end of the bell-die into the latter, as soon as the
sharpened seams of the skelp begin to be bent together and to approach to the place
of welding in the bell-die, I turn the mandrel K, that is else out of the bell (as
show the dotted lines in Fig. 3) into the bell, so that the axis of the bell and that
of the mandrel are the same; than I raise the mandrel into the position shown in
Fig. 4 and secure its shaft S by means of the splint i in the eye A of the lever h.
Hereafter the skelp is drawn through the bell-die and the seams of the skelp are
welded together between the elastic mandrel K and the pulleys R.
The tube having been finished, I turn the mandrel out of the bell die, and the
process can begin a-new with an other skelp.
Instead of making the bell-die of two parts, I can manufacture the same of
course integral.
The pressing pulley R need not be at two opposite sides, but the same is
absolutely necessary at the side where the seams of the strips are welded.
When I arrange the elastic mandrel to balance in the eye A of the lever h, I
need not displace its shaft S to pass through said eye in order to turn the mandrel
out of the bell-die; but the vibrating mandrel is able to give way to be turned out
of the bell.
I am well aware that prior to my invention bell-dies have been already used to
draw metal tubes and that a mandrel has been applied to give internal support to
the tube to be welded, but the feature of my invention is the welding of tubes in a
bell-die and between an elastic mandrel and pulleys, by means of which parts
the sharpened seams of the iron strip are strongly pressed together and thereby
welded.
Having now particularly described and ascertained the nature of my
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1º). In a bell-die for welding metal tubes with sharpened welding seams in one
heat and one process, a bell provided with openings at opposite sides next to its
small end, pulleys or rollers penetrating through said openings to the inner surface
of the bell, an elastic mandrel arranged in the interior of the bell, an aperture in
the wall at the large end of the bell, and means for turning said mandrel through
said aperture out of the bell, essentially as described and for the purpose specified.
2°). In a bell-die for welding metal tubes with sharpened welding seams in one
heat and one process, the combination of a bell provided with openings at opposite
sides next to its small end and an aperture at its large end, pulleys or rollers,
penetrating through said openings to the inner surface of the bell and the circuit
of which corresponds to the inner surface of the bell, an elastic mandrel arranged in
the interior of the bell, said elastic mandrel being provided with a long shaft, a
turning lever pivoted outwardly of the bell on flanges secured to the same and the
under extremity of which lever is formed into an eye, the said shaft of the elastic
mandrel being arranged in said eye and secured by means of a splint, all essentially
as described and for the purpose specified.
3º). In a bell-die for welding metal tubes with sharpened welding seams in one
heat and one process the combination of a bell provided with openings at opposite
sides next to its small end and an aperture at its large end, pulleys or rollers
penetrating through said openings to the inner surface of the bell and the circuit
of which corresponds to the said surface, an elastic mandrel arranged in the
interior of the bell, said elastic mandrel being provided with a long shaft the under
extremity is squared, a turning lever pivoted outwardly of the bell on flanges
secured to the latter, the under extremity of which lever is conically squared to
receive the squared extremity of the said shaft, are essentially as described and for
the purpose specified.
4°. In a bell-die for welding metal tubes, an elastic mandrel having at the place,
where the seams of the skelp are to be welded in the bell, a circular circuit corre-