IMPROVEMENTS IN THE MANUFACTURE OF METALLIC TUBES FOR THE INTERNAL FLUES AND FIREBOXES OF STEAM BOILERS, AND OTHER PURPOSES
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
I, SAMSON Fox, of the Leeds Forge, Armley, Leeds, in the County of York,
Engineer and Ironmaster, do hereby declare the nature of said invention for
" IMPROVEMENTS IN THE MANUFACTURE OF METALLIC TUBES FOR THE INTERNAL
FLUES AND FIREBOXES OF STEAM BOILERS, AND OTHER PURPOSES "
to be as
follows:-
My Invention of "Improvements in the manufacture of metallic tubes for the
internal flues and fireboxes of steam boilers and other purposes" relates to the
formation of such articles in such wise as to dispense with the rivetted or welded
joint usual in such tubes, which as is well known is a source of weakness in such
tubes as ordinarily constructed.-By my invention metallic tubes may be produced
without joint so that they shall be of equal strength throughout or approximately
so, which is when tubes are to be used, a most important feature in the construction
of steam boilers or similar structures subjected to considerable strain. According
to my invention a metallic plate of suitable form, dimensions and quality of
material to produce the required tube, after being heated to a suitable degree, is
shaped to the form of a cup or dish by placing it upon and pressing it through a
circular die, afterwards it is repeatedly heated, drawn or pressed successively
through each of a series of dies of suitable form and size, and subsequently it is
gradually reduced in diameter and at the same time elongated. After the above
described treatment a small portion of the open end of the cup is turned over and
outward so as to form a slight flange for resting upon the die or dies in the
succeeding operations, and to prevent the cup or partially formed tube being drawn
through such die or dies whilst being further elongated. When elongation has
been effected to the desired extent, a hole is formed in the still closed end of the
cup or tube, which after rebeating is placed in a die, and a punch or mandrel is
passed entirely through, thus opening out the remaining portion of what was the
closed end so as to form an additional length of the body of the tube, after which
the beforementioned flange is removed, thus completing the formation of a plain
weldless tube.
In order to impart additional strength to plain weldless tubes formed as above
described they can be afterwards corrugated in accordance with the process
described in the Specification of former Letters Patent granted to me the
30th day of June 1877, N° 2530.

page_text: I, SAMSON Fox, of the Leeds Forge, Armley, Leeds, in the County of York,
Engineer and Ironmaster, do hereby declare the nature of said invention for
"IMPROVEMENTS IN THE MANUFACTURE OF METALLIC TUBES FOR THE INTERNAL
FLUES AND FIREBOXES OF STEAM BOILERS AND OTHER PURPOSES," and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement :-
My invention relates to the formation of metallic tubes for the internal flues and
fireboxes of steam boilers in suchwise as to dispense with rivetted or welded joints
in such tubes, which as is well known is a source of weakness in such tubes as
ordinarily constructed. By my invention, metallic tubes may be produced without
joints, so that they shall be of equal strength throughout or approximately so,
which is, when tubes are to be used, a most important feature in the construction
of steam boilers or similar structures subjected to considerable strain.
According to my invention, a metallic plate of suitable form, dimensions and
quality of material to produce the required tube, after being heated to a suitable
degree is shaped to the form of a cup or dish by placing it upon and pressing it
into a circular die, afterwards it is repeatedly heated, drawn or pressed successively
into each of a series of dies of suitable form and size, and subsequently it is
gradually reduced in diameter and at the same time elongated. After the above
described treatment a small portion of the open end of the cup is turned over and
outward so as to form a slight flange for resting upon the die or dies in the succeeding
operations and to prevent the cup or partially formed tube being drawn through
such die or dies whilst being further elongated. When elongation has been effected
to the extent desired at this particular stage a hole is formed in the still closed end
of the cup or tube, which after re-heating is placed in a die, then a punch or
mandrel is passed entirely through, thus opening out the remaining portion of what
was the closed end and causing it to form an additional length or extension of the
body of the tube, after which the beforementioned flange is or may be removed,
thus completing the formation of a plain weldless tube.
In order to impart additional strength to plain weldless tubes formed as above
described they can be afterwards corrugated in accordance with the process
described in the Specification of former Letters Patent granted to me the
Both
Figs. 1. and 2, shew a metallic plate a, which has been shaped to a circular form
preparatory to being manufactured into a tube according to my invention.
Such plate must be heated previous to each of the several succeeding operations
I now proceed to describe.
Wherever the plate is shewn in all its various stages of manufacture it is marked
with the letter a. The Figures 3, to 13, (excepting Fig. 11,) are in sectional
elevation or sectional plan, as the case may be. Fig. 3, shews the first cupping
operation, a, being the metallic plate under treatment, and b, the circular die into
which it is pressed, by the punch or die c.-Fig. 4, shews the second cupping
operation, d, being the circular die and e, the punch. Fig. 5, shews the operation
of turning over and outward the flange a 1,-f, being the circular die, g, the punch
formed with a collar or projecting head g 1, for effecting the turning over of said
flange a 1, Figs. 6, and 7, shew elongations of the partially formed tube, h, the
circular die, and i, the elongating punch, the same die and punch may suffice for

page_text: both these operations, the punch i, being passed further into the tube as shewn in
Fig. 7. Fig. 8, shews the partially formed tube having the hole a 2, formed in
what was its closed end preparatory to such end being opened out to form an
additional length or prolongation of the tube as previously described. j, Figs. 10,
and 12, being the circular die in which this operation is performed.
The compound punch for effecting the just described elongation comprises the
following parts, namely:-A principal part k, having its head k 1, (shewn in plan
in Fig. 11,) and formed for attachment to a steam hammer or to a suitable press
having a to and fro movement so as to be capable of withdrawing the said
compound punch on completion of the elongation of the tube.. The foot k 2, of the
part k, is suitably formed to partially open the end of the tube and is shewn in
Fig. 10, in the position that obtains at the beginning of such operation. It
has openings, at right angles as shewn in sectional plan Fig. 9 (which is
taken on the line A. A, Fig. 10, for the reception of the parts m, m, m, m, which.
are shewn extended diametrically in Fig. 10, so as to coincide with the inside of
the tube, and are kept in that position by means of the conical part of the central
plug n, until the partially closed end of the tube is opened out-Fig, 12, illustrates
the completion of the operation, the parts m, being moved inward by the contraction
of the tube in cooling.
The central plug n, is arrested in its downward movement by coming into
contact with a fixed part o, whilst the remaining parts of the punch continue their
descent, thus allowing the parts m, to yield so that the whole of the compound
punch can be easily withdrawn. Fig. 13, is a sectional plan on the line B, B, of
Fig. 12, and shews the parts m, in the collapsed state.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
The manufacture of weldless metallic tubes for the internal flues and fire boxes
of steam boilers and other purposes in the manner hereinabove described with
reference to and illustrated in Figs 1. to 12, inclusive of the accompanying
drawings, the partially formed tube being completed by first removing the central
part of its closed end, then forcing a punch or mandrel such as k, through the same
as above set forth.