IMPROVEMENTS IN STEAM BOILERS
Year: 1875

page_text: LETTERS PATENT to John Shaw, of the Neptune Engine Works, Low
Walker on Tyne, in the County of Northumberland, Engineer, for
the Invention of " IMPROVEMENTS IN STEAM BOILERS."
Scaled the 9th December 1875, and dated the 14th June 1875.
PROVISIONAL SPECIFICATION left by the said John Shaw at the
Office of the Commissioners of Patents, with his Petition, on the
14th June 1875.
1.,
I, JOHN SHAW, of the Neptune Engine Works, Low Walker on
Tyne, in the County of Northumberland, Engineer, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN STEAM BOILERS,"
to be as follows:-
:-
My Invention relates to the construction and arrangement of steam
boilers so as to secure strength, to avoid the strains arising from unequal
expansion, to give facility of access for cleansing or repair, to improve
the combustion, and thereby to economise fuel, and, when my Invention
is applied to marine boilers, to render the parts to be moved compara-
tively light and manageable, to provide against the lashing of the water
1

page_text: resulting from the motion of the vessel, and to afford means of working
with a portion of the power when the boiler may be partially disabled.
For this purpose I divide the boiler into two separate lengths, so that
each boiler, constructed according to my Invention, consists of a pair of
equal and similar parts or sections, several of which pairs may be
employed when great power is required. I will describe one such pair
of sections. Each section consists of a casing, which may be cylindrical
or may have flat sides with a round top and bottom. In the lower part
of the section is the fire-box, or there may be two or more fire-boxes,
each being a large tube, preferably cylindrical, extending through the
section from front to back. Above the fire-box or boxes are arranged
tubes also extending through the section. The two sections are set
back to back with a space between them. The bottom of this space is
preferably made in fire-brick or refractory lumps built on a plato
extending from the one section to the other, and this refractory material
is shaped to deflect the flame and gases as may be found convenient.
The top of the space is formed by a fire-brick arch extending across
from the ono section to the other; or instead of such arch each of the
two sections may be made to project at its upper part, so that when the
sections are placed back to back their upper parts meet together, while
a space is left between them below. The sides of the space are also
lined with fire-brick. In this middle space are received the products of
combustion from the fires of the two sections, which are stoked in each
case from the front. From the same middle space the tubes convey the
products of combustion in opposite directions through the two sections
to uptakes, one of which is provided on the front of each section. Each
of these uptakes may lead to a chimney, or by preference one middle
chimney is made to serve for both by leading flues to it over the sections
from both uptakes. A steam receptacle, which is preferably of long
cylindrical form, is placed horizontally over the sections which com-
municate therewith by pipes, and these pipes may be provided with shut-
off valves, so that if one section should be disabled it might be cut off,
the other being still worked.
It is preferred to enclose the steam receptacle wholly or partially
within the flues leading from the uptakes to the chimney, so as morc
freely to utilise the heat of the escaping products for drying the

page_text: marine purposes, is to employ two pairs of sections set side by side with
one middle chimney to which the four uptakes are connected, and one
steam receptacle with which the four sections communicate, the
receptacle being placed in the middle over the space between the two
pairs of sections, and within the flues leading from the uptakes to the
chimney. By thus dividing the boilers into comparatively short lengths
or sections the strains due to inequalities of expansion and contraction are
in great measure avoided, and the strength is increased; also the fire-
boxes, and the middle space into which they open being readily accessible
from both ends, the latter space giving access to the inner ends of the
tubes, cleansing or repair can be readily effected. Moreover, in the said
middle space, with its refractory bottom and sides heated during the
working of the boiler, the combustion of the gases from the fuel is more
completely effected before the products thereof enter the tubes, and thus
there is a diminution of smoke and sooty deposit, and a proportionate
economy of fuel.
For marine purposes cach section, such as I have described, can be
readily moved into or out of its place without necessitating large
openings through the deck of the vessel or great lifting power, and the
water being subdivided in the sections there is a reduction of the
lashing or changes of level that result from the motion of the vessol.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Shaw in the Great Scal Patent Office on
the 11th December 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
SILAW, of the Neptune Engine Works, Low Walker on Tyne, in the
County of Northumberland, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of June, in the year of
our Lord One thousand eight hundred and seventy-five, in the thirty-
cighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Shaw, Her special license
that I, the said John Shaw, my executors, administrators, and
assigns, or such others as I, the said John Shaw, my executors,

page_text: 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,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN STEAM BOILERS," upon the condition (amongst others) that I, the
said John Shaw, 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.
NOW KNOW YE, that I, the said John Shaw, 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, reference being had to the accom-
panying Sheet of Drawings, and to the figures and letters marked
thereon, that is to say :--
My Invention relates to the construction and arrangement of steam
boilers so as to secure strength, to avoid strains arising from unequal
expansion; to give facility of 'access for cleansing or repair, to improve
the combustion, and thereby to economise fuel, and, when my Invention
is applied to marine boilers, to render the parts to be moved compara-
tively light and manageable, to provide against the lashing of the water
resulting from the motion of the vessel, and to afford means of working
-with-a-portion-of-the-power-when-the-boiler-may-be-partially-disabled.-
For this purpose I divide the boiler into two separate lengths, so that
each boiler, constructed according to my Invention, consists of a pair of
equal and similar parts or sections, several of which pairs may be
employed when great, power is required. I will describe one such pair
of sections. Each section consists of a casing, which may be cylindrical
or may have flat sides with a round top and bottom. In the lower part
of the section is the fire-box, or there may be two or more firc-boxcs,
each being a large tube, preferably cylindrical, extending through the
section from front to back. Above the fire-box or boxes are arranged
tubes also extending through the section. The two sections are set
back to back with a space between them. The bottom of this space is
preferably made in fire brick or refractory lumps built on a plate

page_text: ]...
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extending from the one section to the other, and this refractory material.
is shaped to deflect the flames and gases as may be found convenient.
The top of the space is formed by a fire-brick arch extending across
from the one section to the other; or instead of such arch each of the
two sections may be made to project at its upper part, so that when the
sections are placed back to back their upper parts meet together, while
a space is left between them below. The sides of the space are also
lined with fire-brick. In this middle space are received the products of
combustion from the fires of the two sections, which are stoked in each
case from the front. From the same middle space the tubes convey the
products of combustion in opposite directions through the two sections
to uptakes, one of which is provided on the front of each section. Each
of these uptakes may lead to a chimney, or by preference one middle
chimney is made to serve for both by leading flues to it over the sections
from both uptakes. A steam receptacle, which is preferably, of long
cylindrical form, is placed horizontally over the sections which com-
municate therewith by pipes, and these pipes may be provided with shut-
off valves, so that if one section should be disabled it might be cut off,
the other being still worked.
It is preferred to enclose the steam receptacle wholly or partially
within the flues leading from the uptakes to the chimney, so as more
fully to utilise the heat of the escaping products for drying the
steam.
A convenient arrangement of such boilers, as I have described for
marine purposes, is to employ two pairs of sections set side by sido with
one middle chimney to which the four uptakes are connected, and one
steam receptacle with which the four sections communicate, tho
receptacle being placed in the middle over the space between the two
pairs of sections, and within the flues leading from the uptakes to the
chimney. By thus dividing the boilers into comparatively. short lengths
or sections the strains due to inequalities of expansion and contraction
are in great measure avoided, and the strength is increased; also the firc-
boxes and the middle space into which they open being readily accessible
from both ends, the latter space giving access to the inner ends of thic
tubes, cleansing or repairs can be readily effected. Moreover, in the
said middle space, with its refractory bottom and sides heated during the
working of the boiler, the combustion of the gases from the fuel is more
completely effected before the products thereof enter the tubes, and thus

page_text: there is a diminution of smoke and of sooty deposit, and a proportionate
economy of fuel.
For marine purposes each section, such as I have described, can be
readily moved into or out of its place without necessitating large
openings through the deck of the vessel, or great lifting power, and the
water being subdivided in the sections there is a reduction of the
lashing or changes of level that result from the motion of the vessel.
boiler arranged according to my Invention with a space between them
arched over.
Fig. 2 represents by part longitudinal section the modified arrange-
ment wherein the space between the boiler parts is covered by projecting
portions of those parts.
Fig. 3 represents on the right-hand side a transverse section through:
the space between the boiler parts arranged as in Fig. 1, and on the
left-hand side it represents a transverse section through the space
between the boiler parts arranged as in Fig. 2.
Fig. 4. represents on the left side a front elevation, and on the
right side a transverse section through one of the spaces when four
boiler parts are arranged as two pairs of those shewn in Fig. 1, and in
like manner Fig. 5 represents partly an elevation and partly a transverso
section through the space when four boiler parts are arranged as two
pairs of the parts shewn in Fig. 2.
In these Figures the same letters are employed to indicate like a
parts.
A. are the fire-tubes, of which two are shown in cach boiler section,
but of which, as may be readily understood, there may be only one or
more than two in each section%; B is the space formed between cach
pair of sections, which space receives the products of combustion from a
the fires of the two adjoining sections. According to the arrangement
of Figs. 1 and 4 this space is roofed by a fire-brick arch 6, whilst
according to the arrangement of Figs. 2 and 5 it is almost entirely
covered by projecting portions of the two boiler sections. In both
cases the bottom of the space B is formed of firc-bricks 6, and its sides a

page_text: are lined with fire-brick b. O are the tubes through which the products
of combustion pass from the space B to uptakes in front of each boiler
section which may lead to separate chimneys. I prefer however to
gather the uptakes D into one chimney E. F is the cylindrical steam
receptacle which communicates with each section by a pipe, preferably
provided with a shut-off valve, so that any one of the sections can be
thrown out of use when necessary. The steam receptacle F is in the
arrangement of Figs. 1 and 4 placed transversely in the space over the
arch 6. In the arrangement of Figs. 2 and 5 it is placed longitudinally
between the crowns of the sections. In either case it is mostly enclosed
in a chamber communicating with the uptakes, so that it receives heat
from the products of combustion on their way to the chimney, whereby
the steam collected in it is kept hot and dried.
Having thus described the nature of my Invention, and in what
manner the same is to be performed, I claim,—
First. Arranging steam boilers in sections, each pair of such sections
being placed end to end with a space between them lined with refractory
material receiving the products of combustion from the fires, and
delivering them to the boiler tubes, substantially in the manner and for
the purposes herein set forth.
Second. For boilers arranged in the manner referred to in the pre-
ceding claim, providing a steam receptacle partly enclosed within a
space communicating with the uptakes and chimney, substantially as
and for the purposes herein described.
In witness whereof, I, the said John Shaw, have hereunto set my
hand and seal, this Nineteenth day of November, in the year of
our Lord One thousand eight hundred and seventy-five.