IMPROVEMENTS IN THE MANU FACTURE OF TUBULAR STEAM BOILERS
Year: 1863

page_text: LETTERS PATENT to Thomas Wilkinson, of Scarborough, in the County
of York, Engineer, for the Invention of "IMPROVEMENTS IN THE MANU
FACTURE OF TUBULAR STEAM BOILERS."
Scaled the 23rd June 1863, and dated the 14th January 1863.
PROVISIONAL SPECIFICATION left by the said Thomas Wilkinson at the
Office of the Commissioners of Patents, with his Petition, on the 14th
January 1863.
1, THOMAS WILKINSON, of Scarborough, in the County of York, Engineer,
do hereby declare the nature of the Invention for "IMPROVEMENTS IN THE
MANUFACTURE OF TUBULAR STEAM BOILERS," to be as follows:-
Heretofore in constructing tubular steam boilers the tube plate of the
boiler which receives the tubes at the fire-box end of the boiler has had
holes made through it through which the ends of the tubes have been passed.
Now, according to my Invention I form around each hole in the plate a
short tube which projects out from the back of the plate and on the exterior
of each of these short tubes a screw thread is cut in order that the ends of the
tubes may be screwed on to them. The short tubes which project from the
back of the tube plate I form at the same time that the holes are produced
by causing the metal which is displaced from the hole to form the tube, this
I accomplish by causing the punch that makes the hole in the tube plate to
press the metal that is displaced by it into a suitable mould for forming the
tube, and by preference I cause all the holes and tubes to be made at the same
Di

page_text: time by causing as many punches as there are holes to descend simultaneously
through the plate, the back plate of the boiler which receives the back ends of
the tubes has holes formed in it sufficiently large to permit the front ends of
the tubes to be passed through them, and the back end of the each tube is
formed exteriorly with an enlarged nut or head which will not pass through
the holes, this head is as the tube is screwed on to the short tubes above
mentioned drawn against the back plate, and a tight joint is thus formed,
the back plate and tube plate will also by this means be firmly drawn and
held together. The tubular stays which connect the sides of the fire-box to
the exterior casing of the boiler I also arrange in a similar manner, the sides
of the fire-box being made with small tubular projections on to which the
ends of the tubular stays are screwed, the outer ends of the stays pass through
the outer casing, and have heads formed on them which are drawn against
the casing by screwing the stays on to the short tubes on the sides of the
fire-box. The plate which connects the bottom edge of the side of the fire-box
to the bottom edge of the side of the case around the fire-box, I form with
two flanges, one of which is bolted to the side of the fire-box and the other
to the side of the case, the fire-box can thus by removing these bolts be readily
taken out when the tubes and stays have been unscrewed. The flanges
around the edges of the tube plate and also of the front plate, which forms the
front of the firc-box, I form by pressing the plate of metal into a mould of a
suitable form to bend up the edges of the plate to the required extent for re-
ceiving the rivets, the hole in the front plate of the fire-box through which fuel
is supplied to the fire; I also flange in like manner the metal which is displaced
from the opening being formed into a tube which stands out from the plate,
the tube thus formed is sufficiently long to pass across the water space between
the front plate of the fire-box and the front plate of the boiler, and the end of
the tube passes through an opening in the front plate of the boiler and is
secured to it by being rivetted to a piece of angle iron passing round the hole,
or it may be secured in any other suitable manner.
SPECIFICATION in pursuance of the conditions of the 'Letters Patent, filed
by the said Thomas Wilkinson in the Great Seal Patent Office on the
14th July 1863.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of January in the year of our Lord One
thousand eight hundred and sixty-three, in the twenty-sixth year of Her reign
did, for Herself, Her .heirs and successors, give and grant unto me, the said
Thomas Wilkinson, Her special licence that I, the said Thomas Wilkinson,
my executors, administrators, and assigns, or such others as I, the said
Thomas Wilkinson, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain, and Ireland,
"IMPROVEMENTS
the Channel Islands, and Isle of Man, an Invention for
IN THE MANUFACTURE OF TUBULAR STEAM BOILERS," upon the condition
(amongst others) that I, the said Thomas Wilkinson, my executors or
administrators, by an instrument in writing under my, or their, or one of
their hands and seals, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same, was to be performed,
and cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
1
NOW KNOW YE, that I, the said Thomas Wilkinson, do hereby
declare the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
:
Heretofore in constructing tubular steam boilers the tube plate of the boiler
which receives the tubes at the fire-box end of the boiler has had holes
made through it through which the ends of the tubes have been passed.
Now, according to my Invention 1 form around cach hole in the plate a
short tube which projects out from the back of the plate and on the exterior
of each of these short tubes a screw thread is cut in order that the ends of
the tubes may be screwed on to them. The tube plate may be made of
wrought iron or steel, or of copper or alloys of copper. The short tubes which
project from the back of the tube plate I form at the same time that the
holes are produced by causing the metal which is displaced from the hole to
form the tube, this I accomplish by causing the punch that makes the hole
in the tube plate to press the metal that is displaced by it into a suitable
mould for forming the tube, and by preference I cause all the holes and tubes
to be made at the same time by causing as many punches as there are holes
to descend simultaneously through the plate. The punches employed are
pointed, by which they penetrate and drive the metal laterally into the female

page_text: die, thus supposing the metal on which are to be formed short tubes be three-
eighths of an inch thick, and the short tubes are to be one and three-quarters
of an inch long, and two and three-quarters of an inch diameter, the punching
dies used are about one and three-quarters of an inch, of a cylindrical form
beyond which a conical point is formed of about three inches long. The
female die plate is about one and three-quarters of an inch thick, the holes
therein being of the outer diameter of the short tubes. The metal plate of
steel or iron which is to be punched and formed with short tubes is heated to
a proper degree, that is, to or nearly to a white heat which will admit of the
tubes being forged as above explained. When the short tubes have been thus
formed the plate is to be fixed to the bed plate or die, and the punches are
withdrawn by the press. The plate may then readily be lifted off the bed
plate or female die. A screw or other suitable press may be used for actuating
the carrying the punches. The back plate of the boiler which receives the back
ends of the tubes has holes formed in it sufficiently large to permit the front
ends of the tubes to be passed through them, and the back end of each tube
is formed exteriorly with an enlarged nut or head which will not pass through
the holes, this head or nut may be fixed by screwing or otherwise. This head
is as the tube is screwed on to the short tubes above mentioned drawn against
the back plate and a tight joint is thus formed, the back plate and tube plate
will also by this means be firmly drawn and held together. The tubular stays
which connect the sides of the fire-box to the exterior casing of the boiler I
also arrange in a similar manner to the sides of the fire-box, they being made
with small tubular projections produced as above explained, on to which the ends
of the tubular stays are screwed, the outer ends of the stays pass through the
outer casing and have heads formed on them which are drawn against the
casing by screwing the stays on to the short tubes on the sides of the fire-box.
The plate which connects the bottom edge of the side of the fire-box to the
bottom edge of the side of the casing around the fire-box I form with two flanges,
one of which is bolted to the side of the fire-box and the other to the side of
the case, the fire-box can thus (by removing these bolts) be readily taken out
when the tubes and stays have been unscrewed. The flanges around the
edges of the tube plate I make at the same time as the short tubes, the dies
being properly shaped for this purpose as well as for forming the short tubes.
The flanges of the front plate which forms the front of the fire-box I form by
pressing the plate of metal into a mould of a suitable form to bend up the
edges of the plate to the required extent for receiving the rivets; the hole in
the front plate of the fire-box through which fuel is supplied to the fire, I
also flange in like manner in a mould or die, the metal which is displaced from

page_text: the opening being formed into a tube which stands out from the plate, the
tube thus formed is sufficiently long to pass across the water space between the
front plate of the fire-box and the front plate of the boiler, and the end of the
tube passes through an opening in the front plate of the boiler and is secured
to it by being rivetted to a piece of angle iron passing round the hole, or it
may be secured in any other suitable manner.
In place of forging the short tubes and the flanges above mentioned after
the metal plates have been produced, I prefer when using copper or suitable
alloys of copper to cast the plates with short tubes and flanges; the cast
plates are then hammered to close the grain as is well understood. The short
tubes are placed in a bed die similar to that above described, and punches are
forced into the interior of such short tubes.
In witness whereof, I, the said Thomas Wilkinson, have hereunto set my
hand and seal, this Thirteenth day of July, in the year of our Lord
One thousand eight hundred and sixty-three.
THOMAS WILKINSON. (L.S.)