Improvements in Making Tubes or Pipes and in Apparatus therefor..
Year: 1889

page_text: Date of Application, 20th Sept., 1889
Complete Specification Left, 19th June, 1890-Accepted, 13th Sept., 1890
PROVISIONAL SPECIFICATION.
Improvements in Making Tubes or Pipes and in Apparatus therefor..
We, WILLIAM CRAWFORD, Tinsmith, JAMES CRAWFORD, Tinsmith, and WILLIAM
WHITSON CRAWFORD, Clerk, of 49 Arlington Street, Glasgow, in the County of
Lanark, North Britain, do hereby declare the nature of this invention to be as follows,
that is to say :-
Our said invention has for its object the making of tubes or pipes in an improved
and economical manner.
In carrying out our invention we employ processes and apparatus which are to some
extent developments of processes and apparatus described in our earlier Patent Speci-
fications No. 14728 of 1887, and No. 18759 of 1888. We may take as the thing to
start with a cylindrical vessel with a closed end shaped out of a flat sheet or plate as
described in our said earlier Specifications; or we may take a vessel of the said shape
as cast of steel or other suitable metal; and for convenience we will hereinafter refer
to such starting vessel as a pot.
When the pot is a casting, and also when the pot is otherwise formed, if found
necessary or desirable, we first subject it to a special hammering process which whilst
lengthening it to a small extent condenses and toughens the metal. In this hammering
process the pot is placed over a mandril or internal anvil between haminer blocks, to
one, or by preference both or all, of which a small rapidly reciprocating stroke is
imparted by means of one or more hydraulic cylinders or other suitable apparatus.
During the hammering operation the pot is turned more or less rapidly; and is moved
on end so as to slowly pass between the haminer blocks. The hammer faces are made
with a stepped or inclined formation disposed so that the space between them and the
mandril narrows in the direction in which the pot moves on end and the hammer
action follows up the metal as it becomes gradually reduced in thickness.
The pot, in the hammered or unhammered condition, according to the kind, quality,
or condition of its metal is placed in a machine, in which a ram acting internally on
its closed end and actuated by hydraulic pressure, forces it through between shaping
rollers and an annular die which reduce the thickness of its cylindrical part, and cause
it to be considerably elongated. A tube or pipe of required diameter thickness and
length may in some cases be formed at one such operation, whilst two or more
successive operations of a similar kind may be required in other cases.
Heating apparatus is used in the hammering operation as well as in the subsequent
or elongating operation or operations, such heating apparatus being by preference of
the kind, and applied, as described in our earlier Specification No. 18759 of 1888,
hereinbefore referred to.
In a modification of the elongating apparatus which we consider preferable we use
an hydraulic press having at its lower end a cylinder of suitable size and length which
is fitted with two pistons, the lower one moving the ram herein before referred to.
The upper piston is arranged to move a tube through which the rain passes and which
has at its upper end a maudril or internal shaper or resisting block. The entablature
or head of the press is made with a central aperture up through which the tube is
forced by the ram, there being fixed in this aperture a steel ring or annular die.
Immediately under the entablature there are placed a series of steel rollers shaped
like pulleys with concave circunferences, the rollers or pulleys combining so as at
their inner parts to touch each other and form the circumference to a circular aperture.
The circular aperture at the centre between the pulleys is slightly larger than the
annular die a little higher up, but it is a little less than the outer circumference of
the pot; and the pot in being forced through has its thickness' first gradually

page_text: reduced by the action of the rollers and then further reduced on passing through the
annular die.
At a suitable distance below the rollers there is an annular table or shelf on which
the pot is first placed and which also serves to carry the heating apparatus. When
the pot is being placed on the table the ram and mandril are just below it, but as soon
as the pot has been sufficiently heated the ram and mandril are raised by suitably
admitting water under pressure into the hydraulic cylinder. When the ram and
mandril have moved so far up with the pot as that the top of the mandril is just above
the annular die, the mandril ceases to rise and the ram goes on drawing the elongating
pot or tube with it. Cooling water is made to circulate in bollow spaces in the
entablature, and also in the central aperture as soon as the closed end of the pot
reaches the arcular die. Also by suitable pipes and passages cooling water is made
to circulate in the mandril and in the space between the ram and the part of the
elongated pot or tube that may be above the mandril.
Provision may be made for forming faucets and spigots on the ends of a tube or
pipe inade in the machine, by leaving the metal thicker at the ends. At the upper or
entering end the extra thickness may be obtained by making the end piece on the end
of the ram of a tapering form from a diameter equal to that of the mandril to a
smaller diameter at the end. The extra thickness at the other end may be obtained
simply by stopping the elongating action just before the extreme end of the pot reaches
the rollers. The faucet and spigot will be formed on the thickened ends by subsequent
operations.
Dated this Nineteenth day of September 1889.
EDMUND HUNT,
Applicants Agent.
COMPLETE SPECIFICATION.
Improvements in Making Tubes or Pipes and in Apparatus therefor.
We, WILLIAM CRAWFORD, Tinsmith, JAMES CRAWFORD, Tinsmith, and WILLIAM
WHITSON CRAWFORD, Clerk, of 49 Arlington Street, Glasgow, in the County of
Lanark, North Britain, 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 the making of tubes or pipes in an improved
and economical manner.
In carrying out our invention we employ processes and apparatus which are to some
extent developments of processes and apparatus described in our earlier Patent Speci-
fications No. 14728 of 1887, and No. 18759 of 1888. We may take as the thing to
start with a cylindrical vessel with a closed end, shaped out of a flat sheet or plate as
described in our said earlier Specifications; or we may take a vessel of the said shape
as cast of steel or other suitable metal; and for convenience we will hereinafter refer
to such starting vessel as a poi.
When the pot is a casting, and also when the pot is otherwise formned, if found
necessary or desirable, we first subject it to a special hammering process, which whilst
lengthening it more or less condenses and toughens the metal..
The pot, in the hammered or unhammered condition according to the kind, quality,
or condition of its metal, is placed in a machine in which a ram acting internally on
its closed end, and actuated by hydraulic pressure, forces it through between shaping
rollers and an annular die which reduce the thickness of its cylindrical part and cause
it to be considerably elongated. A tube or pipe of required diameter, thickness, and
length, may in some cases be formed at one such operation, whilst two or more
successive operations of a similar kind will probably be required in many cases.
Heating apparatus is used in the hammering operation as well as in the subsequent
or elongating operation or operations, such heating apparatus being by preference of

page_text: the kind, and applied as described in our earlier Specification No. 18759 of 1888.
herein before referred to.
And in order that our said invention and the manner of performing the same may
be properly understood we hereunto append two sheets of explanatory drawings to be
hereinafter referred to, and representing examples of machines made according to.
and for carrying out our invention.
Figures, 1, 2, on sheet, 1, of the drawings are a plan and a sectional elevation
of a machine designed for applying a preparatory hammering process to the pot.
Figures, 3, and 4, on sheet, 2. are a plan and a vertical section of a machine for
elongating the pot or forming it into a tube or pipe.
Figure, 5, is an inverted sectional plan of rollers through between which the pot is
forced, with the framing in which they are held; and
Figure, 6, is an enlarged vertical section showing the pot as passing through between
the rollers and the annular die above them.
In these drawings the same reference letters and numerals are used to mark the
same or like parts wherever they are repeated.
In the haminering machine, Figures, 1, and 2, the pot, P, is placed in an inverted
position over a mandril or internal anvil, A, between hammer blocks, B, of which
there may be two as shown or more, and to one or all of which a small rapidly
reciprocating stroke is imparted by means of one or more hydraulic cylinders, C, to
the rams, B 1, of which the hammer blocks are fixed. The rams, B 1, are, after each
stroke, drawn back into the cylinders, C, by pistons, B 2, in small cylinders, C 1, in
which a constant pressure is maintained. Any other suitable apparatus may be
employed for moving the hammer blocks, B. The anvil, A, is formed on the upper
enlarged end of a tubular mandril, A 1, held at its lower end in a cylindrical shell, A 2.
which is itself arranged to act as a ram or plunger in an hydraulic cylinder, A 3,
carried on trunnions on the bed frame, F, of the machine. The arrangement of the
tubular mandril, A 1, in the shell, A 2, is to allow of the anvil, A, being turned round
and of a stream of water being led through it to prevent it from becoming overheated.
For turning the anvil, A, there is fixed or formed on its tubular mandril, A 1, a ring
of ratchet teeth, and a hand lever, A 4, with a spring pawl is fitted for acting on the
ratchet teeth as in a ratchet drilling brace. The cooling water enters the shell, A 2,
by a pipe, A. 5, and finding its way to a central vertical pipe, A6, pusses through it up
to the anvil, A, which is hollow and is formed with internal flanges or gills to increase
the surface from which the water takes the beat. The water descends from the anvil
through the tubular mandril, A 1, and passes into an annular recess in the upper part
of the shell, 2, and thence away by a pipe, A 7.
When entered into the machine the pot, P, is at first supported on a ring, D, fixed
to the framing, and is inside of a heating chamber or shell, H, also supported on the
ring, D. The heating chamber, H, is formed by an iron shell lined with firebrick, and
which may be in halves hinged together. Round the upper part there are pipes, H1, H2,
for supplying combustible gas and compressed air, with jet nozzles for projecting
blow-pipe flames through orifices into the interior of the heating chamber. The
hot gases escape partly at the upper end of the heating chamber, H, and partly
descend and escape by orifices, H 3, at the lower end; and the intensest heat is
applied to the part of the pot which is for the moment at the top of the heating
chamber. The mandril, A 1, is protected from the heat by a covering, H 4, of
firebrick.
During the hammering operation the pot, P. is turned more or less rapidly by
means of the band lever, A 4; and is moved on end or upwards by admitting
water under pressure into the bottom cylinder, A 3, so as to pass slowly between
the hammer blocks, B. The hammer faces are made with a stepper, or it might
be an inclined formation disposed so that the space between them and the anvil, A,
narrows in the direction in which the pot, P. moves on end, and the hammer
The
action follows up the metal as it becomes gradually reduced in thickness.
hammer blocks, B, are made hollow and water is passed through them. to prevent
them from becoming overheated.

page_text: In the modification of the elongating apparatus shown in Figures, 3, to 6, we
use an hydraulic press having at its lower end a cylinder, K, of suitable size and
length which is fitted with two pistons, K 1, K 2, the lower one, K 1, moving a
ram, R. The upper piston, K 2, is arranged to move a tube, R 1, through which
the rain, R; passes, and which tube has at its upper end a mandril or internal
shaper or resisting block, R 2. The entablature or head, T, of the press is made
with a central aperture, T 1, up through which the elongated pot or tube is forced
hy the ram, R, there being fixed in this aperture a steel ring or annular die, L.
Immediately under the entablature, T, there are placed a series of steel rollers, M,
shaped like pulleys with concave circumferences, these rollers or pulleys combining
so as at their inner parts to touch each other and form the circumference of a
circular aperture. The circular aperture at the centre between the pulleys, M, is
slightly larger than the annular die, L, a little higher up, but it is a little less
than the outer circumference of the unelongated pot, P; and the pot in being
forced through has its thickness first gradually reduced by the action of the
pulleys or rollers, M, and then further reduced on passing through the annular
die, L.
The rollers, M, are fitted to turn upon bosses on pivot bars, M 1, the
outer parts of which are squared to fit up into squared sockets formed for them
in a circular frame, T 2, fixed to the entablature, T; and their ends are bevilled
to fit against each other. The strain on the rollers, M, being upwards, any simple
device may he used to keep them from falling by their weight; such as a set of
small plates bolted to the frame, T 2, after the rollers are placed in position.
Immediately beneath the rollers, M, there is fixed to the frame, T 2, but not shown
in Figure, 5, a plate, Q, made with a central opening contracting upwards, and
having formed round the opening a crown or series of wedge-shaped parts pro-
jecting upwards the points of which enter up between the rollers, M, and prevent
any of the metal of the pot, P, from getting between the rollers at the sides.
The outer part of the plate, Q, is shaped like an annular dish to hold water for
keeping it and the bottoms of the rollers, M, cool. And water is continuously
passed through spaces in the entablature, T, to keep it and the annular die, L
cool.
At a suitable distance below the rollers, M, there is an annular table or shelf, S,
on which the pot, P, is first placed, and which also serves to carry the heating
apparatus, H, which is similar to that used in the hammering machine and herein-
before described. When the pot, P, is being placed on the table, S, the ram, R,
and mandril, R 2, are just below it, as shown in Figure, 4, but as soon as the
pot, P, has been sufficiently heated the ram, R. and mandril, R 2, are raised by
suitably admitting water under pressure into the lower end of the hydraulic
cylinder, K, the space between the two pistons, K 1, K 2, being then full of water.
When the ram, R, and mandril, R 2, have moved so far up with the pot, P, as that the
top of the mandril is just above the annular die, L, as shown in Figure, 6, the
mandril, R 2, ceases to rise, and the ram, R, goes on drawing the elongating pot or
tube with it. As soon as the closed end of the pot, P, reaches the annular die, L.
cooling water is led into the central aperture, T2, of the entablature.
Also by
suitable pipes and passages cooling water is made to circulate in the mandril, R 2, and
in the space between the rain, R, and the part of the elongated pot or tube that, may
be above the mandril, R 2. For this purpose there is fixed within the mandril, R 2, a
pipe, V, for leading in the water and communicating with a pipe, V 1, extending down
the side of the tube, R1, to a flexible supply pipe; and at the opposite side there are
similar pipes, V 2, V 3, for leading the water away. Water is supplied to or drawn
from the space between the pistons, K 1, K 2, in the hydraulic cylinder, K, by a
pipe, K 3, extending up from the upper piston, K 2, and communicating with a flexible
pipe, K 4.
Provision may be made for forming faucets and spigots on the ends of a tube or
pipe made in the machine, by leaving the metal thicker at the ends.. At the upper or
entering end the extra thickness may be obtained by making the end piece of the
ram, R, of a tapering form from a diameter equal to that of the mandril, R.2, to a

page_text: smaller diameter at the end. The extra thickness at the other end of the tube or pipe
may be obtained simply by stopping the elongating action just before the extreme end
of the pot reaches the rollers, M. The faucet and spigot will be formed on the thick
ends by subsequent operations.
In most cases it will be convenient, before placing the pot in position either in the
hammering machine or in the elongating machine, to heat in a separate furnace or
heating apparatus, and to use the apparatus, H, shown and described as placed in the
machines for maintaining the pot at a proper heat during the operations.
When a pot, tube, or pipe has to be subjected to two or more elongating operations
through rollers, M, and annular dies, L, instead of the frame (T 2) carrying these parts
being permanently fixed to the entablature, T, of the hydraulic press, there may be
two or more frames with different rollers and dies arranged like trucks with wheels to
run on rails provided for the purpose-so that such frames may be brought in succes-
sion under the entablature, each being removed after the pot, tube, or pipe has been
passed through, to give place to the next. The rollers or pulleys, M, may vary in
size and number in different cases, and they may be arranged to be driven by gearing,
teeth being formed for that purpose on their sides. In some cases or in some stage or
stages of the elongating operations, the pot, or tube, or pipe may be acted on by the
rollers, M, only, or by the annular die, L, only.
Instead of the arrangement hereinbefore described of the hydraulic cylinder, K,
with the two pistons, K 1, K 2, a separate double-acting cylinder may be employed for
moving the ram, R, and a pair of separate small cylinders may be employed for
moving the inandril, R 2, or other parts.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is
1. The making of a tube or pipe according to the system in which a pot or cylinder
with closed end is subjected to a hammering operation upon its cylindrical surface,
and is afterwards elongated by being forced by an hydraulic ram acting against the
inside of the closed end through between rollers, or through an annular die, or through
between rollers and through on annular die, the pot being kept in a heated state
during the operations, substantially in the manner and by means of apparatus such as
herein before described.
2. The process for hammering cylindrical vessels or pots and the combination of
apparatus for that purpose, substantially as hereinbefore described and as shown in
Figures, 1, and 2, of the accompanying drawings.
3. The process for elongating cylindrical vessels or pots to form tubes or pipes and
the combination of apparatus for that purpose substantially as herein before described
and as shown in Figures 3, to 6, of the accompanying drawings.
Dated this Fichteenth day of June 1890
EDMUND HUNT,
Applicants' Agent.