Improvements in Down-draft Steam Boilers.
Year: 1893

page_text: Date of Application, 30th May, 1893
Complete Specification Left, 28th Feb., 1894-Accepted, 30th 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 relates to steam boilers of the downward-draft water-tube type,
the fire box having its draft opening above the grate and the volatile products of
combustion being deflected downwardly and all caused to pass through the
incandescent mass of fuel on the grate where they are utilized as fuel or consumed
in the combustion chamber beneath the grate. The highly heated current then
travels by a circuitous path among a multiplicity of water-tubes connected at their
ends to water-containing walls diverging as they rise and crowned by steam
drums.
The present invention consists in the combination with a water grate and a
transverse water box with which all the tubes of said grate connect at the inner
end of the fire-box, of a series of water-supply pipes below the grate extending
from the lower portion of the front water wall obliquely upward through the com-
bustion chamber to and into said transverse water box, so as to supply therefrom
water to the grate tubes which rise thence and connect with said water wall. Our
invention further includes water-containing front and rear walls for the water tubes,
such walls being continuous from side to side of the boiler, each diverging from the
bottom, upwardly, for complete clearance, and terminating in a transverse steam
drum. It also embraces such continuous walls and terminal steam drums riveted
longitudinally together at their edges and suitably stayed, in combination with
inclined water tubes connecting said walls.
The improved boiler comprises a water wall forming the front of the fire box,
feed doors and ash door therein. A transverse water-leg, forms the closed inner
This
end of the fuel chamber and deflects downwardly the entire caloric current.
water leg or band extends transversely from side wall to side wall of the boiler,
and communicates with the water-spaces therein.
The grate is composed of parallel water tubes extending obliquely downward
from the water wall to the water-box, which is made independent of the side walls
of the boiler and lies adjacent to and parallel with the lower part of the water-leg.
Water for circulation through the grate tubes is supplied to this water box through
the enlarged oblique supply pipes which descend from said box and enter the lower
part of the front wall of the fire box at each side of the ash-pit door. A main feed-
water inlet pipe is provided and two branch pipes running therefrom through the
combustion chamber to supply the fire box wall and the grate fed therefrom.
By this construction water is drawn from the coolest part, where it is supplied
from the inlet pipe and is heated as it moves through the combustion chamber and
rises through the pipes, by the intense current of combustible gases descending from
the grate, and by the exceedingly high temperature of the combustion chamber
beneath the grate. It is further heated in the transverse water box, and in the
grate tubes on which the fuel rests, the water continually rising and having free
circulation as it advances.

page_text: The body of the boiler is filled in with a multiplicity of inclined water tubes
among which the caloric current travels in a circuitous path, it being deflected by a
fire brick wall in rear of the water leg by inclined fire-brick slabs and by a
depending water leg in the upper portion of the boiler, toward the rear.
The ends of the several water tubes enter the inner plates of the front and rear
water walls these plates being parallel to each other and at right angles to the
tubes and hence somewhat inclined as compared with the vertical front plate of the
front wall, the plates of each wall diverging as they rise to afford abundant
clearance. The outer plate of the rear wall is thus still more inclined from a
vertical position.
The end walls are each continuous from side to side of the boiler, so that all the
pipes open into both of these walls. The pipes will be screwed or expanded into
the inner plates, while the outer plates will have, opposite thereto, screw caps to
afford access to each tube. Similar caps are provided for the supply pipes.
The top of each wall is crowned by a nearly cylindrical steam drum to which
their front and rear plates are firmly riveted, stay strips being provided, at
intervals from front to rear to support the parts against the pressure.
Where the
bottom portion of the drum is apertured but not removed the metal remaining
forms a partial stay.
Each drum is furnished with a man-hole in its end or
elsewhere. A series of enlarged horizontal pipes connects the upper portion of the
front and rear walls to equalize the pressure and for circulating pipes.
The front wall being distinct from the fire-box wall we provide for communication
between them by water pipes rising from the upper part of the wall and entering
the wall above it, to give free circulation for the water rising from the grate.
These pipes may be provided at each side only or they may be placed, at intervals,
on the front also, if preferred. These pipes should be suitably sheathed to prevent
cooling of the water or condensation of the steam therein.
Water is supplied to the rear wall from the transverse main pipe through several
upright tubes.
Dated this 30th day of May 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
DIECIFICATION.
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, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
This invention relates to steam boilers of the downward draft water-tube type,
the fire box having its draft opening above the grate and the volatile products of
combustion being deflected downwardly and all caused to pass through the
incandescent mass of fuel on the grate where they are utilized as fuel or con-
sumed in the combustion chamber beneath the grate. The highly heated current
then travels by a circuitous path among a multiplicity of water-tubes connected
at their ends to water-containing walls diverging as they rise and crowned by
steam drums.
The present invention consists in the combination with a water grate and a
transverse water box with which all the tubes of said grate connect at the inner
end of the fire-box, of a series of water-supply pipes below the grate extending
from the lower portion of the front water wall obliquely upward through the com-
bustion chamber to and into said transverse water-box, so as to supply therefrom
water to the grate tubes which rise thence and connect with said water wall.

page_text: My invention further includes water-containing front and rear walls for the
water tubes, such walls being continuous from side to side of the boiler, each
diverging from the bottom, upwardly, for complete clearance, and terminating in a
transverse steam drum.
It also embraces the fire-box having a front water wall with which all the grate
tubes and supply pipes communicate, in combination with a front water wall above
the fire-box wall and made distinct from it, and with water pipes connecting such
independent lower and upper walls.
In the accompanying drawings
Figure 1 is a longitudinal vertical section through the improved boiler, and
Figure 2 is a front elevation thereof.
A is the water wall forming the front of the fire box, B B the feed doors and
C the ash door therein. D is a transverse water-leg, which forms the closed inner
end of the fuel chamber and deflects downwardly the entire caloric current. This
water leg extends transversely from side wall to side wall of the boiler, and
communicates with the water-spaces therein.
The side walls are made hollow to contain water, and they communicate at the
front corners with the front water walls A and N, at the rear with the wall O,
and at the sides with the upright water legs D and M, the ends of which open into
these water containing side walls.
The grate is composed of parallel water tubes E E E extending obliquely
downward from the water wall A to the water-box F, which is made independent
of the side walls of the boiler and lies adjacent to and parallel with the lower part
of the water-leg D. Water for circulation through the grate tubes E is supplied
to this water box through the enlarged oblique supply pipes G which descend from
said box and enter the lower part of the front wall A of the fire box at each side
of the ash-pit door C. H is the main feed-water inlet pipe, and II two branch
pipes running therefrom through the combustion chamber to supply the fire box
wall and the grate fed therefrom.
By this construction water is drawn from the coolest part, where it is supplied
from the inlet pipe and is heated, as it moves through the combustion chamber and
rises through the pipes G, by the intense current of combustible gases descending
from the grate, and by the exceedingly high temperature of the combustion chamber
beneath the grate. It is further heated in the transverse water box, and in the
grate tubes on which the fuel rests, the water continually rising and having free
circulation as it advances.
The body of the boiler is filled in with a multiplicity of inclined water tubes J
among which the caloric current travels in a circuitous path as indicated by the
arrows; it being shown as deflected by a fire brick wall K in rear of the water
leg D, by inclined fire-brick slabs L, and by a depending water leg M in the upper
portion of the boiler, toward the rear.
The ends of the several water tubes J enter the inner plates of the front and
rear water walls N, O, these plates being parallel to each other and at right angles
to the tubes J, and hence somewhat inclined as compared with the vertical front
plate N of the front wall, the plates of each wall diverging as they rise to afford
abundant clearance. The outer plate of the rear wall O is thus still more inclined
from a vertical position as seen in Figure 1.
The end walls N, O, are each continuous from side to side of the boiler, so that
all the pipes J open into both of these walls. The pipes will be screwed or
expanded into the inner plates, while the outer plates will have, opposite thereto,
screw caps P to afford access to each tube.
The top of each wall N, O, is crowned by a nearly cylindrical steain drum Q to
which their front and rear plates are firmly riveted, stay strips R being provided,
at intervals from front to rear to support the parts against the pressure, as indicated
in Figure 1. Where the bottom portion of the drum is apertured but not removed
the metal remaining forms a partial stay. Each drum is furnished with a man-hole
in its end or elsewhere. A series of enlarged horizontal pipes S connects the upper

page_text: portion of the front and rear walls N, O, to equalize the pressure and for
circulating pipes.
The front wall N being distinct from the fire-box wall A, I provide for com-
munication between them by water pipes T rising from the upper part of the
wall A and entering the wall N above it, to give free circulation for the water
rising from the grate. These pipes T are shown in Figure 2 at each side only but
they may be placed, at intervals, on the front also, if preferred. These pipes
should be suitably sheathed to prevent cooling of the water or condensation of the
steam therein.
Water is supplied to the rear wall O, from the transverse main pipe H, through
several upright tubes U as indicated in Figure 1.
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 downward draft boiler furnace, the upright water leg D communicating
with the side walls of the boiler at the inner end of the fire box, the transverse
water-box F adjacent to but independent of said water leg and side walls, and the
water grate E connecting the water box F with the front water wall A, in
combination with the water supply pipes G, extending from the water box F
obliquely downward and communicating with the lower portion of the front water
wall, through which wall access is had to the interior of said tubes and box,
substantially as set forth.
2. In a downward-draft water-tube boiler, the combination with a multiplicity of
inclined water-tubes among which the caloric current is caused to pass, of front
and rear water-containing walls extending continuously from side to side of the
boiler, formed with parallel inner plates with which the ends of said water tubes
engage, and with outer plates diverging upwardly in opposite directions from said
parallel inner plates, substantially as and for the purpose set forth.
3. In a downward-draft water-tube boiler, the combination with a multiplicity of
inclined water-tubes and with front and rear water-walls having their respective
outer and inner plates upwardly diverging, of steam drums riveted longitudinally
to the upper edges of such diverging plates and suitably stayed, substantially as
set forth.
Dave Cuts 20 day of coruary 1993.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.