CERTAIN IMPROVEMENTS IN WELDED IRON PIPES OR TUBES, TO BE USED AS THE FLUES OF STEAM BOILERS
Year: 1848

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOB
CUTLER, of Spark Brook, near Birmingham, Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Thirteenth day of January, in the eleventh year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Job Cutler, and to one CHARLES ROBINSON, of Spark Brook aforesaid,
Gentleman, Her especial license, full power, sole privilege and authority,
that we, the said Job Cutler and Charles Robinson, our executors, adminis-
trators, and assigns, and such others as we, the said Job Cutler, and Charleś
Robinson, our executors, administrators, or assigns,- should at any time agree
with, and no others, from time to time and at all times during the term of
years. therein mentioned, should and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, our
Invention of "CERTAIN IMPROVEMENTS IN WELDED IRON PIPES OR TUBES, TO BE
USED AS THE FLUES OF STEAM BOILERS;" in which said Letters Patent is. con-
tained a proviso, obliging us, the said Job Cutler and Charles Robinson, by an
instrument in writing under our hands and seals, or under the hand and seal
of one of us, particularly to describe and ascertain the nature of our'said
Invention, and in what manner the same is to be performed, and to cause
the same to be inrolled in Her Majesty's High Court of Chancery within
six calendar'months next and immediately after the date of the said in part

page_text: recited Letters Patent, as in.and by the same; reference being thereunto had,
will more fully and at large appear.
And whereas the said Charles Robinson departed this life on or about the
Fourteenth day of January now last past.
.
NOW KNOW YE, that. in compliance with the said proviso, I, the said
Job Cutler, do hereby declare that the nature of the said Invention, and the
manner in which the same is to be performed, is particularly described and
ascertained in and by the following description thereof, reference being had to
the Drawings hereunto annexed, and to the letters and figures marked thereon
(that is to say):-
The said Invention has for its object the production of iron pipes or tubes so
formed as to secure increased, strength in the parts most exposed to wear, without
the addition of weight in the entire tube, thereby obviating the evils to which
boiler tubes have hitherto been subject, arising from the necessity of increasing
their weight in order to insure a sufficient degree of strength in the parts most
exposed to wear.
-
-
Such being the object in view, the Invention consists in the manufacture, of
welded iron pipes or tubes, whereof the internal diameter, instead of being the
same or uniform throughout the entire length of the tube, is greater at one
-end-than at the other, the outer diameter being the same throughout, so that
the tube will be cylindrical at the exterior and conical at the interior surface.
In such tubes additional thickness (and consequently strength) is given to one
end of the pipe or tube without adding to its entire weight, the extra thickness
of metal in the part desired being secured by gradually collecting into that
part of the tube the metal which is drawn from the remaining portion in the
course of its manufacture.
The machinery and apparatus which I employ in the manufacture of welded
iron pipes or tubes of the kind just described consists of a series of grooved
rolls suitably mounted in standards and driven by toothed wheels, and arranged
so that the pipes or tubes may be readily passed through the whole séries at
one heating of the metal, thereby dispensing with much labor and expense of
manufacture, and also preserving the ductile character of the iron. These
grooved rolls form the outer surface of the pipe or tube, the inner surface being
formed by means of a mandril, over which the skelp and tube are passed
acting in combination with the grooved rolls. The particular form and
arrangement of this mandril, with the other apparatus and mechanism, will be
hereafter described. The, pipe or tube having been completed the mandril i
removed from its interior, and the pipe is then ready for proving and
cutting off

page_text: I proceed now to describe more particularly, by reference to the accom-
panying Drawings, the process of manufacture, and the machinery or apparatus
employed..
Fig. 1 represents a sectional elevation of the grooved rolls (suitably mounted
in standards) in which the welding operation is performed. Fig. 2 is a similar
elevation, shewing the tube or pipe on the mandril, the bulb of the mandril
having been removed; and Fig. 3 is a similar elevation, shewing the pipe or
tube also on the mandril, and just leaving the rolls. Fig. 4 represents the
drawbench in the act of drawing the mandril out of the finished pipe or tube.
Fig. 5. is an elevation of the grooved rolls on their standards, shewing the circle
formed by their grooves. Fig. 6 represents the head or bulb of the mandril
detached; and Fig. 7, the mandril, with its bulb and conical stem. Fig. 8 is
a section of an ordinary cylindrical tube; and Fig. 9 is a similar section of
our new manufacture of tube, cylindrical on the exterior and conical on the.
interior. These four latter Figures are drawn to an enlarged scale. a, a, are
the grooved rolls. 6, the piece of iron or skelp, to form the pipe or tube.
c, the bulb of the mandril, upon which the tube is welded. d, the mandril,
upon which the inside of the pipe or tube is made conical. e is a stop,
mounted as shewn, which supports the end of the mandril d, and against which
the shoulder d thereof abuts. By this means the mandril d is held firmly,
while the skelp or tube is forced over it by the rolls. This stope is formed
with a hinge, so as to be turned down and allow the skelp or tube, with the
mandril d still inside the tube, to pass on to the next pair or set of rolls.. f.is
a stop fixed on the drawbench (Fig. 4), with a die g, against which the end
of the tube abuts (as shewn) when the mandril d is being withdrawn from the
tube. h are the ordinary pliers attached to the chain of the drawbench. Fig. 10
represents the section of three rolls, similar to those employed for straightening
iron shafting, and which I employ for cold rolling the tube, so as to enable the
mandril d to be withdrawn.
I will now proceed to explain the process of manufacture as performed by.
the apparatus and arrangements above described. The skelp having been
prepared in the ordinary manner for lap-jointed tubes, and after being heated,
is placed in the groove of the rolls a and welded on the bulb c of the mandril,
and at the same time forced over the stem d of the mandril. Wher the
tube 6 has left the rolls a, and is on the stem d of the mandril, the head or
bulb c of the mandril is removed, and the tubé in its hot state, with the stem
of the mandril (but which is the mandril in the subsequent stages) still inside,
is-passed through another pair of rolls a, (see Fig. 2), the groove of which rolls
is smaller than the groove in the rolls. through which the tube was welded (see

page_text: Fig. 1). If it is found that the pins or excresences are not sufficiently rolled
smooth or removed, or that the tube is not sufficiently thickened and tapered
in the interior from one end to the other, and the edges of the iron laid quite
smooth both internally and externally, the tube is again passed, with the
mândril still inside,. through the groove of other rolls (see Fig. 3) of still
smaller diameter than the last through which it passed, and so the tube is
continued to be passed, with the mandril d'still inside, through other rolls with
grooves of still smaller diameter, until the external and internal surfaces of the
tube are made smooth and the tube brought to the required dimensions. The
conical mandril d must next be extracted from the inside of the tube b. For
this purpose the tube b, with the mandril inside, is taken to the drawbench
(see Fig. 4), on which are placed two stops f, g, against these stops is a hole
'or die g, against which the tube beds. The mandril d being longer than the
tube, the end of the mandril passes through the hole in the die and is taken
hold of by a pair of pliers h attached to an endless chain, and the bench being
set in motion, the tube being stationary, the mandril d is drawn out of the
tube, If the tube should have become too cold, or fit very closely to the man
dril, I place it.in à muffle or furnace, and bring it to a moderate heat, then cool
the end that is to rest or bed against the die g, and proceed, as before described,
to extract the mandril from the tube. Or, instead of this additional heating
for the purpose of easing the tube so as to admit of the mandril being
extracted, the tube, with the mandril inside, may be cold rolled by means of
three rollers similar to those employed for straightening shafting (as shewn at
Fig. 10); the effect of such cold rolling will be to, ease the tube from off the
mandril, and permit the latter to be withdrawn. The tube being thus welded
and finished at one heat, the quality of the iron of which it is composed is pre-
served from injury much more that is now the case, by being repeatedly heated
to nearly a state of fusion, which destroys the ductile quality of the iron and
renders the pipes or tubes liable to crack and break when being fixed in
boilers. These tubes being passed through the rolls until they are nearly cold,
with the mandril in them, are thereby rendered very smooth, both inside and
out, and there is an uniformity. and equalization of iron all round the tube
The metal of the tube being thicker (say six, seven, or eight wire guage)
at that end which is placed next the fire end of the boiler, and gradually
decreasing in thickness, until at the other end it is not more than eleven o
twelve wire guage (or any other thickness that may be required at either end)
is much lighter. than if continued of the same thickness throughout, and yet a
durable as the thick tubes, now used; while, as the heat passes through the
tube and decreases in intensity, the tube still decreasing in thickness of meta

page_text: enables the water to take up the heat more readily, and thus tends to equalize.
the state of agitation of the water in different parts of the boiler.
In the manufacture as above described the process is conducted continuously,
so as to complete the tube at one heating, but it will be evident that such
manufacture may be conducted at several heatings. For instance, a tube,
cylindrical both externally and internally, manufactured according to any of
the various modes in use, may be taken, reheated, and forced over a conical
mandril, and finished by thickening the metal by pressure on a conical mandril
as already described. It will be obvious that the above thickening by pressure
on a conical mandril may be effected by the use of dies and tongs instead of
rolls, as is well understood by persons conversant with the manufacture of
welded iron tubes; but I believe the use of rolls and the arrangement above
described to be preferable.
Having thus described the nature of the said Invention, and the mode of
carrying the same into effect, I would have it understood that I do not claim
as of this Invention the welding or reducing iron skelps or tubes, or the exclu-
sive use of rolls, dies, mandrils, or other apparatus above described or referred
to, unless such welding, reducing, and apparatus be employed in and adapted
for the said Invention. But what I claim as the Invention intended to be.
secured by the said Letters Patent, is the manufacture, by thickening on a
mandril, of iron tubes, cylindrical at the exterior and conical at the interior,
as above described.
In witness whereof, I, the said Job Cutler, have hereunto set my hand
and seal, this Thirteenth day of July, in the year of our Lord One
dead and fast night