Improvements in Down-draft Steam Boilers.
Year: 1893

page_text: Date of Application, 30th May, 1893
Complete Specification Left, 28th Feb., 1894-Accepted, 5th May, 1894
PROVISIONAL SPECIFICATION.
[Communicated from abroad by CALEB ROBINSON AYER, of 252, Chestnut Avenue,
Boston, Contractor, and GEORGE ALFRED AYER, of Worcester, Massachusetts,
Engineer, both of the United States of America.]
Improvements in Down-draft Steam Boilers.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, do hereby declare
the nature of this invention to be as follows:-
This invention consists of a cylindrical tubular boiler, one feature of which is the
combination with the boiler shell of a substantially tubular steam drum in immediate
contact with and rivetted longitudinally to the upper portion of said shell, com-
munication between them being made through a series of perforations. The drum
is somewhat flattened or concaved along the line of junction and the rivetting is
preferably internal or concealed from view. The boiler shell is strengthened by
stay rods where perforated, and elsewhere by cross stays from the outer to the
inner walls.
The boiler is of the down-draft water-tube type, the water-grate descending from
the water wall below the feed door to a transverse water-box independent of the
side, water-containing walls, such box receiving its supply of water from the lower
portion of the surrounding water-wall through short radial tubes. Adjoining this
transverse box, through which all the grate tubes are supplied with water, is a
water-leg connected to the side walls of the fire-box, closing the inner end of the
fuel chamber, and serving to deflect the caloric current downwardly through the
grate. This current after passing beneath said leg rises among the numerous
water tubes with which the boiler shell is filled, passes over the upper edge of the
same leg, and is deflected downwardly by another water leg standing across its
path as the current returns toward the front upper part of the shell, there to enter the
uptake and pass off. The current thus impinges against the walls of the boiler and
the surfaces of the water legs with great efficiency. The longitudinal water-tubes
extend, by means of sleeves or thimbles, through these transverse water legs, the
caloric current passing such tubes three times and impinging upon them, with much
heating effect, at each passage. The tubes have an inclined position so that
circulation from rear to front is constant. One range of these tubes forms, with a
fire-brick backing, the roof of the fuel chamber or fire-box proper, the fire-brick
running back only to the first water-leg. From the upper part of the shell a water or
steam pipe passes directly through the uptake into the steam drum, its contents being
materially heated in such passage. The end walls of the boiler shell are furnished
with screw-caps opposite to the end of each water tube, to give access thereto if
required. These end walls are in an oblique position, at right angles to the
inclined water tubes. Between the outer and inner end-walls and side-walls are
ample water spaces, supplying water for conversion into steam by the heat applied
in the fire-box and by the caloric current deflected as stated and impinging on the
interior of said walls and the exterior of said tubes. Hand-holes through the side
walls permit clearing of the tubes.
The boiler comprises an outer peripheral wall of the boiler shell, an inner shell,
parallel to the wall and stayed thereto at frequent intervals by transverse bolts or
rivets.
I provide a succession of oblique, longitudinal water pipes which, thickly set,
extend from end to end of the boiler being severally expanded in the heads or end

page_text: plates and affording water communication between the end water-walls. A screw
cap is provided in each head opposite to the end of each tube to give access in
setting or repairing it.
The fire box is composed of the fuel chamber above the grate and the combustion
chamber below the grate. The grate consists of a series of parallel water tubes all
connected with the front water wall and with a transverse water box parallel to said
wall at the inner end of the fuel chamber. This water box is supplied with water
from the lower portion of the peripheral water-wall through radial or upright pipes
and the water so supplied rises through the grate tubes to the front wall and thence
upwardly as the circulation requires. The grate tubes are inclined upwardly from
the box to the water-wall, about parallel to the water-pipes.
The fire box has the feed door and draft-opening above the grate, and the
combustion chamber has a door for removal of ashes. The draft is downwardly
through the mass of fuel upon the tubular grate, there being at the inner end of the
fuel chamber the transverse water leg or wall extending from side to side of the
inner shell of the boiler, the hollow interior of said leg or wall communicating at
each of its ends with the peripheral water-walls of the boiler.
This transverse leg or wall occupies an approximately central position in the
boiler, first deflecting the caloric current downwardly, beneath its lower edge, which
is adjacent to the water-box, and then causing the current to rise among and
impinge upon the several water pipes, until such current escapes over the upper edge
of said wall and strikes another transverse leg, depending from the upper wall of the
inner shell. This deflects the current again downwardly, causing it to pass the
several tubes a second time, after which it rises, passing them a third time and
reaching the uptake.
The water tubes, as stated, run from end to end of the inner shell. In so doing
they pass through the transverse wall or leg, some of them through both these
barriers. Sleeves or thimbles are provided for the tubes to pass through. One
range of these tubes forms, with a fire brick, backing, the roof of the fire-box.
This range of tubes is heated by the direct action of the fire upon the grate, and
by conduction from the fire-brick backing. The tubes below this range extend
only from the water wall to the rear wall.
The steam chamber for the boiler is a nearly cylindrical drum, flattened or con-
caved along its lower face and lying lengthwise upon and rivetted directly to the
outer shell. The drum has its edges turned inwardly so as to be secured internally
and by a double line of rivets to the shell thus affording a simple, strong and
desirable fastening, well resisting the steam pressure. Communication between the
shell and drum is through a series of elongated transverse apertures through the
boiler shell. At each of these apertures a transverse stay-rod is furnished, running
internally directly across within the shell and serving to strengthen it where the
aperture had weakened it. Between the several apertures are broader portions of
the boiler plate not perforated or at all weakened. The water line will usually be
above the junction of the shell and drum. A dry-pipe to draw steam from and a
manhole for the workman are provided.
The uptake being near the front end of the boiler, in front of the second leg, we
provide an outlet for steam or highly heated water, from the top of the front end-
wall into the drum or steam chamber, such outlet consisting of an enlarged pipe
passing directly through the uptake, where the caloric current is utilized again to
impart its heat to the water or steam within the pipe.
Hand holes may be formed through the boiler shell, giving lateral access to the
tubes, so that ashes accumulated thereon may be blown away or otherwise removed.
With the downward draft no soot accumulates, such matter being consumed in the
fire-box.
DandL
ليمي
1

page_text: Improvements in Down-drait Steam Boilers.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
This invention consists of a cylindrical tubular boiler, one feature of which is
the combination with the boiler shell of a substantially tubular steam drum in
immediate contact with and rivetted longitudinally to the upper portion of said
shell, communication between them being made through a series of perforations.
The drum is somewhat flattened or concaved along the line of junction, and the
The boiler shell is
rivetting is preferably internal or concealed from view.
strengthened by stay rods where perforated, and elsewhere by cross stays from the
outer to the inner walls.
The boiler is of the down-draft water-tube type, the water-grate descending from
the water wall below the feed door to a transverse water-box independent of the
side, water-containing walls, such box receiving its supply of water from the lower
portion of the surrounding water-wall through short radial tubes. Adjoining this
transverse box, through which all the grate tubes are supplied with water, is a
water-leg connected to the side walls of the fire-box, closing the inner end of the
fuel chamber, and serving to deflect the caloric current downwardly through the
grate. This current, after passing beneath said leg rises among the numerous
water tubes with which the boiler shell is filled, passes over the upper edge of
the same leg, and is deflected downwardly by another water-leg standing across
its path as the current returns toward the front upper part of the shell, there to
enter the uptake and pass off. The current thus impinges against the walls of
the boiler and the surfaces of the water-legs with great efficiency.
The longitudinal water-tubes extend, by means of sleeves or thimbles, through
these transverse water legs, the caloric current passing such tubes three times and
The tubes have
impinging upon them, with much heating effect, at each passage.
an inclined position so that circulation from rear to front is constant. One range
of these tubes forms, with a fire-brick backing, the roof of the fuel chamber or
fire-box proper, the fire-brick running back only to the first water-leg.
From the upper part of the shell a water or steam pipe passes directly through
the uptake into the steam drum, its contents being materially heated in such
passage. The end walls of the boiler shell are furnished with screw caps opposite
to the end of each water tube, to give access thereto, if required. These end
walls are in an oblique position, at right angles to the inclined water tubes.
Between the outer and inner end-walls and side-walls are ample water spaces,
supplying water for conversion into steam by the heat applied in the fire-box and
by the caloric current deflected as stated and impinging on the interior of said
walls and the exterior of said tubes. Hand-holes through the side walls permit
clearing of the tubes.
In the accompanying drawing,
Figure 1 is a longitudinal vertical section through the improved boiler and
Figure 2 is an end view, partly in vertical transverse section.
A represents the outer peripheral wall of the boiler shell, and B the inner shell,
parallel to the wall A and stayed thereto at frequent intervals by transverse bolts
or rivets. C C and D D are respectively the ends of these cylinders A. B, the
water walls or spaces enclosed between them being indicated by the letter E.

page_text: F denotes the succession of oblique, longitudinal water pipes which, thickly set,
extend from end to end of the boiler being severally expanded in the heads or end
plates D D and affording water communication between the end water-walls E.
A screw cap G, is provided in each head C C opposite to the end of each tube F,
to give access in setting or repairing it.
The fire box is composed of the fuel chamber H above the grate I, and the
combustion chamber H¹ below the grate. The grate consists of a series of
parallel water tubes I, all connected with the front water wall E and with a
transverse water box J parallel to said wall at the inner end of the fuel chamber.
This water box is supplied with water from the lower portion of the peripheral
water-wall through radial or upright pipes K, and the water so supplied rises
through the grate tubes to the front wall E, and thence upwardly as the circula-
tion requires. The grate tubes are inclined upwardly from the box J to the
water-wall, about parallel to the water-pipes F.
The fire-box has the feed door and draft opening L above the grate, and the
combustion chamber has a door M for removal of ashes. The draft is downwardly
through the mass of fuel upon the tubular grate, there being at the inner end
of the fuel chamber the transverse water leg or wall N extending from side to
side of the inner shell B of the boiler, the hollow interior of said leg or wall
communicating at each of its ends with the peripheral water-walls of the boiler.
This transverse leg or wall N occupies an approximately central position in the
boiler, first deflecting the caloric current downwardly, beneath its lower edge, which
is adjacent to the water-box J, and then causing the current to rise among and
impinge upon the several water pipes F, until such current escapes over the upper
edge of said wall N and strikes another transverse leg O, depending from the upper
wall of the inner shell B. This deflects the current again downwardly, causing it
to pass the several tubes a second time, after which it rises, passing them a third
time and reaching the uptake P.
The water tubes F, as stated, run from end to end of the inner shell B. In so
doing they pass through the transverse wall N or leg O some of them through both
these barriers, as seen in Figure 1. Sleeves or thimbles Q are provided for the
tubes to pass through. One range of these tubes forms, with a fire-brick backing R,
the roof of the fire-box. This range of tubes is heated by the direct action of the
fire upon the grate, and by conduction from the fire-brick backing R.
below this range extend only from the water wall N to the rear wall E.
The tubes
The steam chamber for our boiler is a nearly cylindrical drum S, flattened or
concaved along its lower face and lying lengthwise upon and rivetted directly to
the outer shell A. The drum S has its edges turned inwardly so as to be secured
internally and by a double line of rivets T to the shell A, thus affording a simple,
strong and desirable fastening, well resisting the steam pressure. Communication
between the shell and drum is through a series of elongated transverse apertures V
through the boiler shell. At each of these apertures a transverse stay-rod U
is furnished, running internally directly across within the shell A and serving to
strengthen it where the aperture has weakened it. Between the several apertures
are broader portions of the boiler plate not perforated or at all weakened. The
water line will usually be above the junction of the shell and drum. A dry-pipe
to draw steam from is shown at W, and a man-hole for the workman at X,
Figure 1.
The uptake P being near the front end of the boiler, in front of the second leg O,
we provide an outlet for steam or highly heated water, from the top of the front
end-wall E into the drum or steam chamber S, such outlet consisting of an enlarged
pipe Y passing directly through the uptake, where the caloric current is utilized
again to impart its heat to the water or steam within the pipe.
Hand-holes Z, Figure 2, may be formed through the boiler shell, giving lateral
access to the tubes F, so that ashes accumulated thereon may be blown away or
otherwise removed. With the downward draft no soot accumulates, such matter
being consumed in the fire-box.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me by
my foreign correspondents, I declare that what I claim is :-
1. In a down-draft steam boiler, a water grate connected at its front end with
the water wall of the boiler and descending obliquely therefrom, in combination
with a transverse water box, with which the inner ends of the grate tubes com-
municate, said box receiving its water supply from the lower parts of the peripheral
water wall through radial connecting pipes, substantially as set forth.
2. In a down-draft steam boiler, the combination of a water jacket and water
end-walls with a multiplicity of internal water tubes connecting said end-walls,
among which tubes the caloric current passes transversely thereof, and with a
transverse water leg and a fire-brick roof-plate for the fuel chamber, serving to
deflect such current downwardly through the grate, substantially as set forth.
3. In a down-draft steam boiler, the combination of a water-jacket and water-
containing end-walls with a multiplicity of inclined water tubes among which the
caloric current circulates, and with two or more water legs or transverse walls
in the path of the current, serving to deflect it against said tubes, substantially as
set forth.
4. In a down-draft steam boiler, end and peripheral water-walls, transverse
water-legs or walls and a series of longitudinal water pipes, in combination with
sleeves or thimbles in said transverse legs or walls through which said pipes pass,
substantially as set forth.
5. In a down-draft steam boiler, a cylindrical boiler shell, having end and
peripheral water-walls, an enclosed fire box and a transverse water leg at the rear
end of the fire-box, serving to deflect the caloric current downwardly and against
the bottom and rear water wall, in combination with a substantially cylindrical
steam drum, mounted upon and rivetted directly to said cylindrical shell, and with
a succession of openings through said shell into said drum, substantially as set
forth.
6. In a down-draft steam boiler, end and peripheral water walls, inclined water
tubes connecting said end walls, and a down-draft fire box, enclosed between such
walls, in combination with transverse water-legs, deflecting the caloric current to
the uptake at the front of the boiler, a steam drum above said boiler in rear of the
uptake, and a steam pipe from the top of the front water wall to said drum through
the uptake, substantially as set forth.
Deted this 20th day of 1904
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant..