Improvements in Apparatus for Use in the Manufacture of Tubes of Polygonal Section.
Year: 1893

page_text: Date of Application, 2nd Sept., 1893—Accepted, 14th Apr., 1894
COMPLETE SPECIFICATION.
[Communicated from abroad by THE BABCOCK & WILCOX COMPANY, of New
York, in the United States of America, Steam Boiler Manufacturers.]
Improvements in Apparatus for Use in the Manufacture of Tubes
of Polygonal Section.
I, WALLACE FAIRWEATHER, C.E., of 62 Saint Vincent Street in the City of
Glasgow, Chartered Patent Agent, do hereby declare the nature of this invention
and in what manner the same is to be performed, as communicated to me, to be
particularly described and ascertained in and by the following statement:-
The object of the invention is to provide an apparatus for heating and forging
metal plates, namely, scarfing the edges of the plates and subsequently lay-welding
the scarfed edges after the plate has been folded and for forming tubes of
rectangular or other polygonal cross-section adapted for use as headers for
sectional steam boilers or other purposes, all the sides of the plate being folded
without removing it from the die and the folding operation completed by successive
strokes of the press in a common direction, the die being adapted to form
and hold the work and operate at different angular positions to the line of
compression.
The invention further relates to expanding mandrils adapted for making tubes
of rectangular or other polygonal cross sectional form, the object being to provide
a mandril that may be readily expanded in place or contracted for withdrawal
from the finished tube.
The mandril is made up of longitudinal corner plates and an expanding core
extending throughout its length which by a longitudinal movement is adapted to
expand or contract the plates uniformly and simultaneously.
The apparatus is specially designed for use in the manufacture of headers for
sectional steam boilers wherein the plates and headers are conveniently
manipulated during the different processes to which they are subjected and the
objection and trouble of reheating are in a great degree avoided.
Referring to the accompanying drawings,
Figure 1 represents a longitudinal sectional elevation of the scarfing furnace or
furnace section, the automatic carrier on which the plates are first introduced,
and the scarfing rolls, the position representing the deposit of the plate in the
furnace.
Figure 2 is a similar partial sectional elevation, the position representing the
insertion of the guiding or drawing rod.
Figure 3 is a longitudinal sectional elevation similar to Figure 1, the position
representing the delivery of the plate to the scarfing rolls.
Figure 4 is a horizontal section taken on the line -x of Figure 3.
Figure 5 is a longitudinal sectional elevation shewing the welding furnace or
furnace section, the automatic conveying mechanism and maudril and the welding
rolls, the position representing the deposit of the tube in the furnace.
Figure 6 is a similar partial sectional elevation, the position shewing the carrier
and the tube in section.
Figure 7 is a horizontal section taken on the line y-y Figure 5.
Figure 8 is an enlarged detail view, shewing" in" plan the stripping pawls
adjacent to the welding rolls.
Figure 9 is a sectional elevation similar to Figure 5, also illustrating the
overhead frame for hoisting the mandril, the advanced position of the mandril
being illustrated.

page_text: Figure 10 is an end elevation of Figure 7, shewing the compound furnace and
the scarfing and welding rolls.
Figure 11 is an enlarged detail view taken partly in section shewing the
hydraulic cylinder and carrier truck.
Figure 12 is a cross section of Figure 11 taken on the line 2-2.
Figure 13 is an enlarged elevation of the welding rolls and their gearing.
Figure 14 is an end view partly in section shewing the folding die in operating
position in a suitable press.
Figure 15, a side elevation of Figure 14.
Figure 16 an enlarged cross section of the die and a suitable mandril inserted
therein, the position indicated being preparatory to the folding operation.
Figure 17 a similar view shewing the first folding operation.
Figure 18 shews a perspective view of the piece partially folded as in
Figure 17.
Figure 19 is a cross sectional view shewing the preparatory position for the
second folding operation.
Figures 20, 21, 22 and 23 illustrate the remaining steps of the operation
hereinafter referred to.
Figure 24 is an enlarged side elevation partly in section shewing the press and
devices for holding the mandril in position.
Figure 25 an end view of Figure 24.
Figure 26 is a longitudinal elevation shewing one form of construction of my
improved mandril, taken on the line of Figure 29 shewing also a suitable
operating cylinder therefor, the said mandril appearing in an expanded position.
Figure 27 a similar view taken partly in elevation shewing the mandril
contracted.
Figure 28 a plan view of Figures 26 and 27, the position corresponding to
Figure 26.
Figure 29 a cross section taken on the line y-y Figure 26.
Figure 30 a cross section taken on the line 2- Figure 27.
Figure 31 is an enlarged cross section on line y¹-y of Figure 26, the position of
the parts being similar to that in Figure 29.
Figure 32 is a plan view partly in section shewing another form of construction
of my improved mandril, the parts being in an expanded position.
Figure 33 a side view partly in longitudinal section, its position corresponding to
Figure 32.
Figure 34 a side elevation partly in section shewing the parts in a contracted
position.
Figure 35 is an enlarged cross section taken at ' ' Figures 34 and 38.
Figure 36 an enlarged cross section taken at y'-y' Figure 34 shewing the parts
contracted.
Figure 37 an enlarged cross section taken at y-y' Figures 33 and 38 shewing
the parts expanded.
Figure 38 is an enlarged longitudinal section through the end of the mandril
corresponding in position to Figure 33.
In Figures 36, 37 and 38 the tube is indicated in position upon the mandril.
In the scarfing process Figures 1, 2, 3 and 4, the edge of the plate K is first
connected with a holder 3 of the carrier M in its retracted position outside the
furnace A and advanced thereby into the furnace through a passage 2 by means of
the hydraulic cylinder D and conveying mechanism illustrated in enlarged detail
Figure 11 as follows; 40 is the piston rod, 41 the piston, 42 the cylinder, 43 the
water supply to the respective opposite sides of the piston, 44 a protecting jacket
forming an annular space around the cylinder 42 and E a connected travelling
truck with track way 50 and rollers 52-53 to which the carrier M is coupled by
means of the rod 4. After the plate is deposited into the furnace as shewn in
Figure 1, the carrier M and holder 3 is retracted, the doors 5, 5, closed and the
plate subjected to the proper degree of heat. The doors 5, 5, are then opened and

page_text: the carrier M and its holder 3 again advanced and moves the plate forward to the
scarfing rolls as shewn in Figure 3, from which it is deposited upon the frame 51,
the carrier being then returned to the first position. The scarfing rolls as will be
seen in Figures 4, 7 and 10 are provided with central circumferential grooves 14
adapted for the insertion of the guiding or drawing rod 16 in the manner indicated
in Figure 2. The upper scarfing roll F is further provided with beveled flanges 15,
as indicated in the said figures.
The plate K with its edges beveled or scarfed is then removed to a suitable press
or other forming machine for folding the plate into a quadrangular tube having the
scarfed edges lapped in suitable position for welding. The folded tube I is then
taken to the welding furnace H as shewn in Figure 5, placed upon the table J and
deposited in the position shewn by means of the carrier L and brought to a welding
heat.
The carrier L is composed of a movable trough or plate which is temporarily
placed on the table J and connected by any suitable means to an arm 8 of the
truck E to be pushed into the furnace H and withdrawn. When out of use the
carrier may be laid aside as indicated by dotted lines in Figure 7.
G, Figures 5 to 9 inclusive, represents the welding rolls aligned with the
passages 6, 6, and the table J and rolls G, are provided with suitable flanges 10, 10,
for confining and guiding the corners of the tube I and there are vertical guide
rolls 11 for guiding the tube into its welding rolls. The scarfing rolls F and
welding rolls G are for convenience placed upon or driven from a common
shaft 20.
H, in Figures 5 to 9 inclusive represents the furnace adapted to heat the folded
tube I preparatory to welding. Passages 6, 6, are provided to the furnace H for
the introduction and delivery of the tube I. J is the table from whence the tube I
is delivered to the furnace H and L the tube carrier movable on the table J, and
through the furnace H, said carrier being provided with suitable pawl 7 for
retaining the tube. The carrier L, is operated by the hydraulic cylinder D, which
is shewn in the drawings as common to both carriers M and L pertaining to the
scarfing and welding rolls respectively. The truck E carrying the extremity of
the piston rod of the cylinder D is also utilised in common and there is a standard
thereon for pushing the mandril when it is advanced into the tube in the furnace.
9, 9, are the furnace gates or doors adapted to open or close the passages 6, 6.
Above the table shewn at Figure 5, the mandril C is suspended which after the
carrier L has been removed to its position at the side of the table J out of line
with the furnace, is lowered on to the table; and engaged with the arm 8, of the
truck E. The tube being brought to the welding heat, the doors 9 of the furnace
are raised and pressure is again applied to the truck E by the cylinder D, so as
to advance and force the mandril C, into the heated tube which is lying in the
furnace, carrying the same along and passing it between the welding rolls & where
the seam in the tube is squeezed down on the mandril with such force that the two
edges are pressed together forming a welded rectangular tube. The mandril C in
passing through the welding rolls with the tube continues on its travel until the
tube is deposited on the table 12 as shewn in Figure 9, wherein the finished tube is
stripped from the mandril. Within such table 12, there are provided stripping
pawls 13, 13, at each side of the tube adapted to hold the same, which prevent its
retraction when the maudril is withdrawn."
The mandril C which is supported when not in operation in a suitable overhead
frame N is indicated in Figure 9, the suspended position of the same being indicated
in Figure 5. The mandril is provided with an elongated stand O, adapted to reach
through the furnace H when the mandril is passed through the welding rolls G.
The links 21, 21, afford means of engaging the chains 22 with the mandril and
there is a plunger cylinder 23 to which the chains 22 are rigged in a suitable
manner to hoist or lower the mandril upon the table J. The mandril C is adapted
to expand by the longitudinal movement of a central core F¹ extended therein and
at the extremity of the core F' there is provided upon the frame 26 carrying the

page_text: mandril a suitable hydraulic cylinder 27 for advancing or retracting the core F.
The cylinder 27 is supplied with water through a jointed or other flexible tubing 28
indicated in Figure 9 at all positions of the mandril and there is a lever 29 for
controlling the fluid pressure for expanding or contracting the inandril.
The cylinder 27 which withdraws the central core F¹ of the mandril relaxes the
sides and loosens the same in the tube. Pressure is then applied to the reverse
side of the hydraulic cylinder D which operates the carrier E and the carrier and
mandril are forced back to their original position. The stripping pawls 13 retain
the tube while the mandril is thus withdrawn.
The welding rolls G G appear more fully in Figure 13, which figure also
illustrates the cross section of the mandril C shewing its core F1, expanding plate 30
and expanding faces 31 likewise designated in Figure 5.
With reference to the construction of the die for forming and holding the
plate K, Figures 14 and 15 represent the framework of a hydraulic or other
suitable press adapted for operating the die. E is the folding die having a trough
shaped interior corresponding to the exterior of the tube to be formed. B, is the
pillow block for supporting the die E, which is provided with a semi-cylindrical
concave surface a fitting the semi-cylindrical convex surface of the die E. At
different stages of the operation the die E is adapted to be tilted the one way or
the other at different angles to the line of compression as represented in Figures 17
to 23 inclusive and in order to impart such motion any suitable mechanism may be
employed. I illustrate a hand lever F at one end of the press for the purpose.
Moreover in lieu of the semi-cylindric faces between the die E and support B,
suitable trunnions or other equivalents may be substituted to admit of the rotative
movement of the die upon its axis substantially at right angles to the line of
compression.
D is the compressing die or head of the press. C is the mandril which during
the working corresponds in size to the interior size of the tube to be formed.
The frame ff of the mandril is supported in its proper position, indicated in
Figures 16, 24 and 25, preparatory to the insertion of the plate K or during the
withdrawal of the formed tube therefrom by means of links k and pins embracing
the extremities thereof, suspended on the ends of the head D. The pins m which
appear in Figure 25 are designed to hold the die E in place when the mandril and
tube are lifted therefrom.
In the operation of the invention, the plate K which has been scarfed or beveled
at its edges s, s in the manner hereinbefore described or by other suitable means
placed in the position upon the die E, shewn in Figure 14, the mandril C being
suspended over it upon the upper die D. In this relation pressure is applied to the
press forcing the plate K into the die E and producing the trough shape form, as
shewn in Figure 17.
The bottom die E is then rotated a part of a revolution to the angular position
shewn in Figure 19, and one projecting edge of the plate turned over the top of
the mandril C as at Figure 20. The die is then leveled and the bent edge pressed
down as at Figure 21.
The die E, is then rotated in the opposite direction and the other projecting edge
of the plate folded over as at Figure 22 and the die being again brought into level
position as at Figure 23 the two edges are squeezed down together, thus forming
on the mandril C. a tube of rectangular cross section with the two edges of the
plate lapped in position for welding.
The die E when brought to the position shewn in Figure 19 and during the
compression of the press, may if desired be rotated toward its horizontal position
simultaneously with the compression movement of the press so that the edge of the
plate is brought from the position in Figure 19 to the position in Figure 21 by a
continuous motion. Automatic connection may for this purpose be provided for
imparting to the die E, such rotary movement from the movable head of the
press.
The construction of the mandril herein shewn in Figures 26 to 31 inclusive is

page_text: well adapted for use in conjunction with a folding die E indicated by dotted lines
in Figures 29 and 30. For this purpose the mandril C is provided with longi-
tudinally divided corner sections a b c d as clearly appear in cross section in
Figures 29 and 30 which are designed to be expanded in opposite directions
preparatory to folding the plate about the same in the die E as shewn in
Figure 30.
The corner pieces a, b, c, d are each provided at suitable intervals longitudinally
with a series of wedge shaped projections 1, 11 having flat faces and within the
same there is a longitudinally movable core F provided at corresponding intervals
in its length with a cooperating series of corresponding projections jjj around
which core are assembled the several sections a, b, c, d.
When the expanding plates are spread by the action of the core F a solid
bearing is secured upon the opposite flat faces of the projections 1, 1, j,j.
The movable pieces a, b, c, d, are carried in a suitable frame f, having collars n, n,
at either extremity thereof for preventing the assembled mandril sections from
dropping apart and also confining them against longitudinal displacement.
Upon the extremity of the frame ff a hydraulic cylinder H is securely bolted
and upon the extremity of the core F there is provided a yoke I upon which the
respective differential plungers op engage the smaller plunger o operating to insert
the wedges and expand the mandril before the plate is folded thereon and the
larger plunger p operating to withdraw the wedges and collapse the mandril as in
Figure 30, after the tube has been folded and exterior pressure exerted upon the
mandril.
Links having removable pins are suspended from the head D of the press as
indicated in Figure 26 and the mandril is thereby suspended by its frame f
preparatory to its operation By the removal of the pins the mandril and folded
tube may be removed bodily from the die E.
.
Referring to the welding mandril shewn in Figures 32-38 the stock C¹ which
is a continuation of the expanding faces a', constitutes the frame corresponding
to fin Figure 28, on which the operating cylinder H is supported. The expanding
faces a', and also the expanding faces c', d' on the remaining sides of the mandril
are interiorly provided at suitable intervals longitudinally with a series of wedge-
shaped and flat faced projections 1, 1, 1, similar to those herein before described with
reference to Figures 26 to 30 inclusive and the longitudinally movable core F
within the mandril is also likewise provided at corresponding intervals with the
series of wedge-shaped and flat faced projections j,j,j. The shank F of the core F
is also provided with a yoke connected as before described with the differential
plungers of the operating cylinder H. The inner extremities of the plates c'd' are
connected together by the studs and the outer extremities of the said plates c', ',
as also the outer extremities of the welding faces a', b', are provided with lugs s, s
that are retained together upon a central pin t, Figure 35 and all sides of the
mandril are thus retained together. A shoulder or latch or other suitable device
is provided at u, u on the body of the mandril for the purpose of pushing the tube
toward the welding rolls when the mandril has been inserted the proper distance.
V represents a travelling roller which runs upon a suitable way designed for
supporting the stock of the mandril and its cylinder when moved by the carrier
arm of the welding furnace in the manner hereinbefore described.
The operation of the mandril shewn in Figures 26 to 31 inclusive is as follows:
The mandril is first expanded by the plunger o which moves the core wedges j into
contact with and between the flat faces of the section wedges i as seen in Figure 26.
The metal plate is then laid on the folding die E and pressed by the compression
die D of the press into the form shewn at Figure 29 and subsequently folded over
at the projecting edges by the oscillation of the die E as hereinbefore described.
After the plate has assumed the tubular form shewn in Figure 30, and the head D
retracted, pressure is applied to the plunger p of the cylinder H which moves the
core Fendwise to release the wedges as shewn in Figures 27 and 30, the mandril
being then withdrawn.

page_text: The operation of the mandril shewn in Figures 32 to 38 inclusive is as follows;
The mandril is first inserted into the tube, lying within the welding furnace or
like intended place, and the sides a', ', c', d then expanded by means of the
plunger o which moves the core wedges into contact with and upon the flat faces
of the sectional wedges as before and thereby secures a solid bearing against the
end of the tube abutting on the shoulder u, u' as seen in Figures 33 and 38. The
advancement of the mandril toward the welding rolls then being continued
the seam in the tube is welded over one of the faces a¹ or band after delivery
from the rolls, the tube is secured from a return motion by a suitable latching
device while the core F of the mandril is retracted by means of the plunger p and
the mandril withdrawn.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed as communicated to me
I declare that what I claim is :-
:-
1. In an apparatus for heating and forging metal the combination of a suitable
furnace having a through-way passage forging rolls aligned with said passage upon
one side of the furnace an actuating plunger and cylinder provided with a fluid
supply device and conveying mechanism for the work upon the other side of the
furnace adapted to advance said work into and then through the furnace to the
rolls; said mechanism consisting in a table, a truck connected to the said cylinder
plunger and interchangeable devices for supporting the work at the different stages
of operation substantially as described.
2. In an apparatus for welding tubes, the welding rolls, a conveying mechanism
for feeding the work to the rolls, a mandril adapted to form a welding core for
the tube, the same being provided with means for connecting it to the said
conveying mechanism and in the path of the conveying mechanism a suitable
heating furnace substantially as described.
3. In an apparatus for heating and welding tubes, the welding rolls, a conveying
mechanism the through-way furnace interposed between the same and the rolls a
welding mandril for the tube adapted for attachment to said conveying mechanism
and above the latter a suitable hoist and operating cylinder for placing and
removing the mandril thereon, substantially as described.
4. In a tube welding machine, the combination of a suitable welding furnace,
welding rolls upon one side thereof, a conveying mechanism upon the other side,
a fluid pressure cylinder for operating the conveying mechanism, an expansive
mandril for the tube and operating cylinder for the mandril adapted for attachment
to the said mechanism and means for supplying pressure to the mandril cylinder
at all positions in the travel of the same, and above a conveying mechanism a
suitable hoist for the mandril and fluid pressure operating cylinder for the hoist.
5. In a machine for welding tubes, the combination with the welding rolls
adapted for the passage of the mandril, and the receiving trough 12, of stripping
pawls substantially as described upon the delivery side of the rolls within said
trough for the purpose set forth.
6. In an apparatus for heating and forging metal, a series of forging rolls, a
plurality of furnaces or furnace sections provided with through-way passages
aligned therewith and conveying mechanism for the rolls provided to each said
passage and supporting devices for the work connected to an actuating cylinder
and plunger provided with a fluid supply device whereby successive operations on
different pieces of work are or may be simultaneously performed.
7. The combination in a press for forming rectangular or other polygonal tubes
from a single plate of a trough shape die corresponding to the exterior of the
tube to be formed, having a convex surface fitting into a concave seat or support
a reciprocating compression die or plunger for forcing the plate within the forming
die, a mandril arranged within the trough shaped tube and die and means for
oscillating the forming die into different angular positions to the line of com-
pression.

page_text: 8. A sectional mandril adapted for the formation thereon of tubes of rectangular
cross sectional shape, consisting of longitudinal corner strips and a core provided
with means for moving outward the said corner strips of the mandril.
9. A sectional mandril adapted for the formation thereon of tubes of rectangular
cross sectional shape, the same consisting of longitudinal corner strips having a
series of interior wedge shaped and flat faced projections and between the said
longitudinal strips a core having corresponding projections engaging therewith and
means for moving said core longitudinally substantially as described.
10. In combination with a sectional mandril adapted for the formation thereon
of tubes of rectangular cross sectional shape a core provided with means for
moving outward the sections of the mandril, and a cylinder attached to the
mandril, a plunger within the cylinder attached to the core of the mandril, and
means for operating the said plunger by fluid pressure.
11. The combination with a sectional mandril, adapted for the formation thereon
of tubes of rectangular cross sectional shape a core provided with means for moving
outward the sections of the mandril, two cylinders of different sizes attached to
the mandril and plungers therein of different size connected to the said core of
the mandril: the smaller for expanding, the larger for contracting the same by
actuating said core in opposite directions and means for operating the said plungers-
by fluid pressure.
Dated this 1st day of September 1893.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.