Improvements in the Manufacture of Lock Joint Metallic Tubes and in Machinery or Apparatus Employed in the said Manufacture.
Year: 1886

page_text: Date of Application, 19th Aug., 1886.
Complete Left, 13th May, 1887.
Complete Accepted, 14th June, 1887.
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Lock Joint Metallic Tubes and
in Machinery or Apparatus Employed in the said Manufacture.
I WILLIAM ALLMAN of the firm of Cope Allman and Company of Unity Tube
Works Icknield Square Birmingham in the County of Warwick Tube Manufacturers
do hereby declare the nature of this Invention to be as follows:-
My invention has reference to the kind of metallic tubes commonly called lock
joint tubes and also known as consolidated joint tubes. The said tubes are chiefly
employed for casing or covering iron tubos in the manufacture of various articles and
are made from strips of thin sheet brass or other metal or alloy. The strip of metal
of which the tube is to be made has its edges so turned that when the strip is bent
into a cylindrical form the said edges may be hooked or engaged with one another.
The edges thus connected without brazing or soldering may by a drawing or rolling
process either with or without an internal tube of iron be flattened and consolidated
and the seam or junction obliterated or nearly obliterated.
The manufacture of lock joint inetallic tubes as ordinarily conducted is effected by
a drawing process the strip of metal being drawn through a draw plate and upon a
tool or mandril so shaped as to give the strip of metal and its edges the required
shape. The edges are hooked together by hand.
In making a lock joint metallic tube according to my invention I operate upon the
strip of metal by rolling instead of by drawing. I bend the edges at right angles to
the body of the strip one edge being bent in one direction and the other in the
opposite direction. I further bend the said edges so as to incline them at an acute
angle to the body of the strip and give to the strip a trough like figure. I afterwards
operate upon the trough like strip by rolls so as to make the edges overlap the said
overlapping edges hooking or engaging together on the removal of the pressure of
the rolls

page_text: The machinery or apparatus I employ in carrying my invention into effect consists
of sets of rolls. The first set consists of a pair situated horizontally and grooved so
as to turn the edges of the strip at right angles as herein before described. The second
set consists of a pair of rolls also situated horizontally and these are so grooved as to
cause the edges of the strip to make an acute angle with the middle part of the strip.
The third set consists of a pair of rolls situated horizontally and so grooved that they
give a trough like figure to the strip. The last set of rolls consists of three rolls one
of which is horizontal and the other two vertical. The trough shaped strip is sup-
ported in a semi circular groove in the horizontal roll and the vertical rolls one of
which is at a somewhat higher level than the other curve inwards the sides of the
trough shaped strip depressing one edge to a somewhat lower level than the other and
making them so overlap one another that on passing from the rolls the edges of the
partially formed tube engage or hook with one another by the slight expansion or
opening out of the tube on the removal of the pressure of the rolls. The tube may
be drawn upon an inner iron or other tube or on a mandril to compress and consolidate
the junction when it is not used as a casing tube.
By manufacturing lock jointed tubes in the manner and by the use of the machinery
or apparatus described the said tubes are made more rapidly and economically than
by the ordinary method of manufacture and the metal is not subjected to the injurious
strain to which it is subjected in the ordinary drawing process.
Dated this Nineteenth day of August 1886

page_text: in Machinery or Apparatus Employed in the said manufacture.
I WILLIAM ALLMAN of the firm of Cope, Allman and Company of Unity Tube
Works, Icknield Square, Birmingham in the County of Warwick, Tube Manufac-
turers do hereby declare the nature of my invention and in what manner the same is
to be performed to be particularly described and ascertained in and by the following
statement:-
My invention has reference to the kind of metallic tubes commonly called lock
joint tubes and also known as consolidated joint tubes. The said tubes are chiefly
employed for casing or covering iron tubes in the manufacture of various articles and
are made from strips of thin sheet brass or other metal or alloy. The strip of metal
of which the tube is to be made has its edges so turned that when the strip is bent
into a cylindrical form the said edges may be hooked or engaged with one another.
The edges thus connected without brazing or soldering may by a drawing or rolling
process, either with or without an internal tube of iron, be flattened and consolidated
and the seam or junction obliterated or nearly obliterated.
The manufacture of lock joint metallic tubes as ordinarily conducted is effected by
a drawing process the strip of metal being drawn through a draw plate and upon a
tool or mandril so shaped as to give the strip of metal and its edges the required
shape. The edges are hooked together by hand.
In making a lock joint metallic tube according to my invention I operate upon the
strip of metal by rolling instead of by drawing. I bend the edges at right angles to
the body of the strip one edge being bent in one direction and the other in the
opposite direction. I further bend the said elges so as to incline them at an acute
angle to the body of the strip and give to the strip a trough like figure. I afterwards
operate upon the trough like strip by rolls so as to make the edges overlap the said
overlapping edges hooking or engaging together on the removal of the pressure of
the rolls.
The machinery or apparatus I employ in carrying my invention into effect consists
of sets of rolls. The first set consists of a pair situated horizontally and grooved so
as to turn the edges of the strip at right angles as hereinbefore described. The
second set consists of a pair of rolls also situated horizontally and these are so
grooved as to cause the edges of the strip to make an acute angle with the middle
part of the strip. The third set consists of a pair of rolls situated horizontally and so
grooved that they give a trough like figure to the strip. The last set of rolls consists
of three rolls, one of which is horizontal and the other two vertical. The trough
shaped strip is supported in a semi circular groove in the horizontal roll and the

page_text: vertical rolls, one of which is at a somewhat higher level than the other, curve inwards
the sides of the trough shaped strip, depressing one edge to a somewhat lower level
than the other and making them so overlap one another that on passing from the
rolls the edges of the partially formed tube engage or hook with one another by
the slight expansion or opening out of the tube on the removal of the pressure of
the rolls. The tube may be drawn upon an inner iron or other tube or on a mandril
to compress and consolidate the junction when it is not used as a casing tube.
I will now proceed to describe with reference to the accompanying Drawings my
method of manufacture in conjunction with the machinery which I employ in
conducting the said manufacture.
Figure 1 represents in side elevation; Figure 2 in front or end elevation and
Figure 3 in plan, machinery constructed according to my invention for the manufac-
ture of lock joint metallic tubes; Figure 4 represents in longitudinal vertical section
the first set of rolls detached from the machine; Figure 5 represents in longitudinal
vertical section, the second set of rolls detached from the machine; Figure 6 repre-
sents in longitudinal vertical section the third or troughing set of rolls detached from
the machine and Figure 7 represents in longitudinal vertical section the last set of rolls,
by which the parts of the lock joint are made to overlap, detached from the machine.
The separate views of the rolls Figures 4, 5, 6 and 7 are drawn to a larger scale than
the same parts in the complete machine Figures 1, 2 and 3 ; Figure 8 represents in
cross section the flat strip of brass or other ductile metal or alloy from which the lock
joint tube is to be made. Figure 9 represents the said strip after it has been operated
upon by the first set of rolls; Figure 10 represents the said strip after it has been
operated upon by the second set of rolls; Figure 11 represents the strip Figure 10
after it has been troughed by the operation of the third set of rolls and Figure 12
represents the partially mado tube after its edges have been made to overlap by the
operation of the last set of rolls.
The same letters of reference indicate the same parts in the several Figures of the
Drawings.
The first set of rolls consists of the pair of geared horizontal rolls marked a, a the
opposite end of each roll being provided with a flange a² (see Figure 4) by the
operation of which flanges the edges of the flat strip of metal Figure 8 guided to
the rolls a, a by the guide b in front of them are bent at right angles to the body of
the strip, one edge c being bent in one direction and the other edged being bent in
the opposite direction as represented in Figure 9.
The second set of rolls consists of the pair of horizontal geared rolls e, e nearly
similar to the first pair of rolls a, a excepting that the acting flanges e², and parts
adjacent to the said flanges are so shaped as to incline the bent edges c, d of the strip
passed between them in the manner represented in Figure 10.
The third set of horizontal rolls consists of the convex top roll fand the concave
lower roll by the operation of which rolls f, f upon the strip represented in
Figure 10 it is troughed in the manner represented in Figure 11..
The last set of rolls consists of the horizontal roll g and the two vertical rolls h, h³
(see Figure 7). The bottom horizontal roll g has a semi-circular groove in it in which
groove the trough strip Figure 11 is supported and the acting edges of the two
vertical rolls h, are at different levels (see Figure 7) by the action of which vertical
rolls the sides of the trough strip Figure 11 are curved inwards and one edge is
depressed to a somewhat lower level than the other edge so that the said edges overlap
one another as seen in Figure 12, whereby on the tube passing from the rolls and
the pressure being removed from the partially made tube, its edges engage or lock
with one another by the expansion or opening out of the tube.
The strip Figure 8 being passed in succession through the several sets of rolls
described and represented, a lock joint partially formed tube is made, the joint of the
tube being afterwards flattened and consolidated and the seam or junction obliterated
or nearly obliterated by drawing or rolling the said tube either with or without an
internal iron tube as before described.

page_text: The first and second sets of rolls a, a and e, e are geared together by the toothed
gearing at i, Figures 2 and 3, and the third set of rolls, is driven from the first
set of rolls by a band passing over the drawing pulleys & and l. The rolls of the
fourth set are not driven but are rotated by the frictional contact of the tube passing
between them. In the manufacture of lock joint tubes of a diameter less than about
three quarters of an inch, the fourth set of rolls g, h, h² may be dispensed with. In
this case the completion of the tube is effected by hand on a stretching bench.
When the fourth or last set of rolls g, h, h³ is not required to be employed in
conjunction with the other sets of rolls, the said last set is detached from the
machine.
By means of distance pieces the first and second sets of rolls may be fitted to
operate upon strips of different widths for the formation of tubes of different
diameters.
For this purpose I make up each of the rolls of a tubular roll carrying the flange
at one end and two end fixing collars all sliding upon a key on the shaft of the roll.
By placing distance pieces of different lengths, capable of sliding on the key of the
shaft, between one of the fixing collars and the plain end of the tubular roll the
length of the roll can be adjusted to suit the width of the strip to be fashioned.
The third and fourth sets of rolls are changed as required to suit the diameter of the
tubes being manufactured.
By manufacturing lock joint tubes in the manner and by the use of the machinery
or apparatus described and represented, the said tubes are made more rapidly and
oconomically than by the ordinary method of manufacture and the metal is not
subjected to the injurious strain to which it is subjected in the ordinary drawing
process.
Having now particularly described and ascertained the nature of my invention
and the manner in which the same is to be performed I declare that I claim as my
invention of "Improvements in the manufacture of lock joint metallic tubes and in
machinery or apparatus employed in the said manufacture
;-
First Making lock joint tubes or consolidated joint metallic tubes by rolling, the
rolling process being conducted and the strip of sheet brass or other sheet metal or
alloy being operated upon substantially in the manner hereinbefore described and
illustrated in the accompanying Drawings.
Secondly The machinery or apparatus herein before described and illustrated in
the accompanying Drawings to be employed in the manufacture of lock joint or con-
solidated joint metallic tubes made by the rolling process claimed in the first claim :
that is to say, machinery or apparatus consisting either of three or four sets of rolls,
the first and second sots bending and inclining the edges of the strip, from which
edges the joint is to be made, the third set of rolls troughing the bent edged strip and
the fourth set of rolls, when used, curving inwards the sides of the trough strip
and causing its edges to overlap one another for the purpose and substantially as
described and illustrated..
WILLIAM ALLMAN.