IMPROVEMENTS IN OR APPLICABLE TO STEAM BOILERS OR GENERATORS
Year: 1883

page_text: LETTERS PATENT to James Watt Boulton of Ashton-under-Lyne, in the
County of Lancaster, Engineer, for an Invention of "IMPROVEMENTS IN
OR APPLICABLE TO STEAM BOILERS OR GENERATORS."
PROVISIONAL SPECIFICATION left by the said James Watt Boulton at
the Office of the Commissioners of Patents on the 20th January 1883.
JAMES WATT BOULTON, of Ashton-under-Lyne, in the County of Lancaster,
Engineer, "IMPROVEMENTS IN OR APPLICABLE TO STEAM BOILERS OR GENERATORS,"
Firstly, My invention relates to water tubes for steam boilers and its object is to
so construct and arrange them that they will present a large surface to the action of
the heat of the furnace or flues, produce a free circulation of the water and a rapid
generation of steam, while their joints or junctions with the tube plate in which
they are inserted will be unaffected by expansion or contraction.
My invention consists in constructing the said water tubes of U form, the two
ends being inserted and making joints with a tube plate or with the sides of the
flue, the tube entering the furnace or flue and being exposed to the action of the
heat therein.
One leg of each U tube (by preference that exposed to the greatest heat) has a
tube inserted in it so as to prolong and extend it a few inches above the water
surface in the boiler. The other leg has or may have a thin tube in the centre of
its interior extending the length of the leg and a little above its open end.
The heat will cause the water in the boiler to descend one leg of the tube, or
descend the central tube in that leg, and ascend the other leg and pass up its
prolongation to escape above the surface of the water.
The inserted tube has or may have its end bent, or has or may have a cap upon
it, to conduct or throw the steam and water passing up the tube back to the surface
of the water in the boiler.
Secondly, My invention consists in the combination and arrangement of
water tubes according to the first part of my invention with vertical types
of boilers.

page_text: The furnace or fire box of the boiler is made cylindrical, by preference, with a
flat top or crown, and the chimney flue may pass from either tho centro or sido of
the furnace or fire box.
Water tubes according to the first part of my invention, are inserted in the top
or crown of the fire box, which thus forms a tube plate.
The water tubes are arranged in any desired manner, but by preference the plane
of the two legs of each U tube is placed in a radial line from the centre of the
circular fire box, that is, one leg is placed near the centre and the other leg nearer
the outside circumference of the fire box, and that leg which is prolonged above
the water level of the boiler, is nearer the centre of the fire box.
These tubes are thus arranged to radiate round the fire box..
Several of these tubes are or may be placed in the same radial line from the
centre of the fire box.
Thirdly, My invention consists in combining the said water tubes according to
the first part of my invention with the furnace or flues of horizontal types of boilers
and with existing boilers, by inserting them in the crowns or upper sides of the
furnaces or flues of such boilers

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said James Watt Boulton in the Great Seal Patent Office on the
19th July 1883.
"
JAMES WATT BOULTON, of Ashton-under-Lyne, in the County of Lancaster,
Engineer, "IMPROVEMENTS IN OR APPLICABLE TO STEAM BOILERS OR GENERATORS
Firstly. My invention relates to water tubes for steam boilers and its object is to
so construct and arrange them that they will present a large surface to the action
of the heat of the furnace or flues, produce a free circulation of the water and a
rapid generation of steam while their joints or junctions with the tube plate in
which they are inserted will be unaffected by expansion or contraction.
My invention consists in constructing the said water tubes of U form, the two
ends being inserted and, making joints with a tube plate or with the sides of the
Blue, the tube entering the furnace or fluo and being exposed to the action of the
beat therein.
One leg of each U tube (by preference that exposed to the greatest heat) has a
tube inserted in it so as to prolong and extend it a few inches above the water
surface in the boiler, or the water level is or may be above the extended or long
leg of the tube.
The heat will cause the water in the boiler to descend one leg of the tube, and
ascend the other leg and pass up its prolongation to escape at or above the surface
of the water.
The inserted tube has or may have its end bent, or has or may have a cap upon
it to conduct or throw the steam and water passing up the tube back to the surface
of the water in the boiler, or in any desired direction to increase the circulation and
equalize the temperature.
Secondly, My invention consists in the combination and arrangement of
water tube's according to the first part of my invention with vertical types
of boilers.
The furnace or fire box of the boiler is made cylindrical by preference with a flat
top or crown and the chimney flue may pass from either the centre or side of the
furnace or fire box.
Water tubes according to the first part of my invention are inserted in the top
or crown of the fire box which thus forms a tube plate. The water tubes are
arranged in any desired manner but by preference the plane of the two legs of
each U tube is or may be placed in a radial line from the centre of the circular fire
box, that is, one leg is placed near the centre, and the other leg nearer the outside
circumference of the fire box, and that leg which is prolonged above the water level
of the boiler is nearer the centre of the fire box.
These tubes are thus arranged to radiate round the fire box. Several of these
tubes are or may be placed in the same radial line from the centre of the fire box.
In some cases a greater number of the said tubes, may be inserted when they are
each placed with the plane of the two legs perpendicular to a radial line from the
axis of the fire box, and in some cases my invention consists in combining the tubes
so that one tube or series of tubes will cross and come within and between the bend
of the other tube or series of tubes
Thirdly. My invention consists in combining the said water tubes according
to the first part of my invention with the furnace or flues of horizontal types of
boilers, and with existing boilers, by inserting them in the crowns of the fire boxes
or upper sides of the furnaces or flues of such boilers.
Fig 1 is a sectional elevation of one of the U tubes shown detached on an
enlarged scale, according to the first part of my invention.

page_text: a, is the tube plate in which both ends of the tube are secured by expanding the
tube above and below the tube plate, or into a groove in the tube plate, or by any
other known mode of securing boiler tubes in tube plates.
One leg of the tube b has a prolongation formed by a short tube b¹ driven tightly
into the tube, the upper end of this added tube may terminate at or above the
ordinary water level of the boiler, but by preference it ends one or two inches
below that level.
"
The added tube b' is or may be open ended, but to check any tendency to
priming" the end is closed by preference and an opening made on one side of it
and this opening is placed in a direction to assist in circulating the water in the
boiler.
The end of the prolongation 6' is or may be closed by a cap or plate rivetted
to ono side of the tube and bent over the end, one side of the tube b' being cut
away.
If desired the U tubes may be formed by a bend or coupling b* into which the
two legs b are screwed or otherwise secured so as to be water and steam tight, as
illustrated by fig 2.
Fig 3 is a sectional elevation and fig 4 a plan section above the crown or tube
plate a, illustrating the application of my invention to the vertical type of
boilers.
C₁ is the shell or outer casing of the boiler, a' the fire box; the crown a of which
forms the U tube plate;
d the chimney flue which if desired may pass from the side of the fire box.
e are the furnace bars, and ƒ the fire door opening.
The U tubes are shown in figs 3 and 4 with the plane passing between the two
"legs of each tube at a right angle to a radial line from the vertical axis of the
boiler. The openings or outlets from the added tubes b¹ are, by preference, all in
the same direction to cause the water to tend to circulate round the vertical axis of
the boiler.
A block of fire brick material g or other arrangement is suspended by a rod or
- bolt from the centro of the chimney-or by other means to compel the heated
gases and products of combustion to pass first between the U tubes before going to
the chimney flue.
In some cases a cylinder h of sheet iron is formed to fit in and divide the space
"between the outer shell and fire box of the boiler into two divisions.
This cylinder has short radial pieces h¹ secured to it to touch the fire box a¹ and
thus keep the cylinder h in position.
These radial pieces ' touch the bottom of the space between the fire box and
shell, and form feet for the cylinder h to rest upon, which cylinder does not extend
to the bottom but leaves a space for water descending down between the cylinder
and shell to pass under the lower end of the cylinder and up the space between
it and the fire box. There is also a short inner cylinder hª extending upwards from
the tube plate a as shown.
The object of the two cylinders h and h³ is to promote a free circulation in the
water between the fire box and shell of the boiler.
Figs 5 and 6 are views corresponding to figs 3 and 4 respectively, but on a
smaller scale showing another arrangement of U tubes applied to the vertical type
of boiler.
One set of U tubes are here shown with the plane passing between the axes of
the two legs placed in a radial line from the vertical axis of the boiler, and with
another set of U tubes placed between and within the other tubes, and at right
angles thereto.
These latter U tubes are shorter in length, as they come within and between the
bends of the former.
It will also be seen that the central tubes are arranged to pass across the opening
to the outlet flue d, one set of these tubes being within the other, thus dispensing
with the block g in the modification-shówn by fig 3.

page_text: Figs 7, 8 and 9 illustrate the application of my invention to horizontal types of
boilers.
My improved U tubes are or may be applied to, and fixed in the crown of
Locomotive fire boxes arranged to come between the stay bars or beams and leaving
space to get at the ordinary horizontal Blue tubes.
They are or may also be applied to marine and other boilers in like manner
where they do not prevent access for cleaning or repairing the ordinary flue tubes.
Fig 7 is a cross and fig S a partial longitudinal section illustrating the applica-
tion of my improved U water tubes to an horizontal flue.
b is the central tube; b³ and b are the next tubes further back on one side of it,
and and be the next tubes further back on the other side of the central tube, an'l
so on, to any desired extent.
Fig 9 shows part of the bottom of a boiler supposed to have an external
furnace.
b are a series of U water tubes coming into the furnace or flue.
These tubes are or inay be placed as shown, and other tubes are or may be placed
immediately behind them to come opposite the spaces between the first row of
tubes, and so on, to any desired extent.
I have now particularly described the nature of my said invention and the modes
of carrying the same into effect, and claim as my invention.
Firstly. Water tubes for steam boilers or generators made in the U form, one leg
of each tube being prolonged and its end or opening made to terminate above the
level of the opening at the end of the other leg, substantially as hereinbefore
described and illustrated by the drawings.
Secondly, Water tubes made in the Ū form for steam boilors or generators having
one leg longer than the other, and one U tube made shorter than the other, and
made to cross and come within and between the bends of the other U tubes,
substantially as hereinbefore described and illustrated by the drawings.
Thirdly. In the vertical type of steam boiler the combination and arrangement of
U water tubes, substantially as hereinbefore described and illustrated by figs 3 and
4 of the drawings.
Fourthly. In the vertical type of boiler, the combination and arrangement of.
U water tubes, substantially as herein before described and illustrated by figs 5 and
6 of the drawings.
Fifthly. In the vertical type of boiler the combination of U water tubes, and
cylinders (h and h²) substantially as hereinbefore described and illustrated by
figs 3, 4, 5 and 6 of the drawings.
Sixthly. In the horizontal type of boilers, the combination of U water tubes,
substantially as herein before described and illustrated by figs 7, 8 and 9 of the
drawings.
In Witness whereof I the said James Watt Boulton, have hereunto set my hand
and seal this thirteenth day of July in the year of our Lord one thousand eight
hundred and eighty three.
JAMES. W. BOULTON, LS.