Improvements in Water-heating and Steam-generating Apparatuses.
Year: 1895

page_text: Date of Application, 28th May, 1895-Accepted, 20th July, 1895
COMPLETE SPECIFICATION.
Improvements in Water-heating and Steam-generating Apparatuses.
I, WILLIAM HENRY LAIRD, of No. 14 Mount Morris Park, West, in the City
of New York, in the State of New York, one of the United States of America,
Broker, 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 means for heating water, whether the object be merely
to raise the temperature of the water to a moderate degree, to produce steam of
low tension, or to produce steam of high tension, and the object is to fully utilize
the heat resulting from the combustion of the fuel and effect a near approximation
of perfect combustion.
While adhering to the same principles in construction and operation at all times
I prefer to construct my apparatus, where it is to be employed for merely heating
water or supplying steam at a low tension, somewhat differently from the same
apparatus where it is to be employed for supplying steam at high tension, as in a
locomotive boiler, for example.
When the apparatus is to be employed for heating water, or producing steam at
a moderate tension, for heating a house for example, I prefer to employ the
construction illustrated in Figures 1, 2 and 3, wherein-
Figure 1 is a vertical, mid-section of the apparatus in the plane indicated by
line 1, 1, in Figure 2;
Figure 2 is a plan and horizontal section in the plane indicated by line 2, 2, in
Figure 1, and
Figure 3 is a horizontal section in the plane indicated by line 3, 3, in Figure 1.
This construction is as follows:
In the drawings, A indicates an ordinary tubular boiler; A¹, its main draft-flue;
A", its breeching, terminating in a suitable stack; and A, its return draft-flues.
The boiler and its associate parts are supported by suitable masonry, which,
preferably, extends up in front thereof to form a down draft-flue from the spaces
around the water-head to the main draft-flue A'.
B indicates a suitable base for the water-heater, which forms an ash-pit for the
grate-bars C, located thereabove, said grate-bars being of any approved or desired
type and mounted in the plate D, which plate generally supports the casing and
water-sections.
E indicates the casing or shell which encloses the heater.
Mounted on the plate D, are water-sections F, which, in the drawings, are four
in number and arranged so as to form substantially a square. These water-sections,
however, as well as the other parts constituting my improved heater, can be so
shaped as to make the heater circular in cross-section, in which case each water-
section would be in the form of a quarter of a circle. Again, as many water-
sectious as may be desired may be used and connected together in any suitable
manner, so as to preserve the continuity of the high bridge-wall surrounding the
entire grate-bars. As the water-séctions are now made, save for the front one,
but one pattern is necessary, which duplication saves considerably in the cost of
production of the heater.
The ends of the sections are, preferably, mitered, so that they will expand and
contract equally under the existing arrangement of draft-flues, the inner face being
of less area, being subjected to the greater amount of heat, will expand to a
.;

page_text: greater extent, proportionately, than the outer face, which, although of greater
area, is subjected to a less degree of heat; therefore, its expansion is less. By
mitering the corners, the expansion of the inner and outer faces is equalized, and
in order to preserve their relation, I preferably arrange at the corners angle-stirrups
which hold the sections together.
Projecting inwardly from the faces of the sections, are heat-conducting pins F¹,
which are, preferably, staggered relative to each other, and whose function is, to
absorb and transmit beat to the water in the sections, at the same time diffusing
the heat throughout the entire surface. At the lower, inner edges of the water-
sections are air-conducting ports F", which open into the ash-pit and terminate in
the combustion chamber above the grate-bars, at a point preferably about the
lower end of the fuel magazine.
Gindicates a belt feed-pipe, which is supplied from some suitable source of
supply, with water to be heated, said belt leading into the bottoms of all the
water-sections F.
Leading from the tops of the water-sections F, are pipes H, which discharge
into a continuous water-head I, located at the upper portion of the heater, said
water-head being connected by a pipe J to the boiler A or other receptacle for the
heated water.
K indicates a cap or cover for the heater, which is preferably formed with
openings over the water-head, said openings being closed by doors L, which give
access to the interior for the purpose of cleaning the flues, the dirt in the flues
between the shell E and the water-section F being disposed of through doors D',
in the plate D, and the dirt on the inner faces of the water-sections and on the
heat-conducting pins falling through the grate-bars into the ash-pit.
The cap or cover K is also formed with a central opening, giving_access to the
fuel magazine from the top, which opening is closed by a door M. Draft openings
are, also, located, in the cover K, around the fuel magazine, they being regulated
by draft-plates N.
The fuel-magazine is composed of double walls O and P, the former, which is
the outer, having mounted thereon feet O', which extend laterally and rest upon the
water-sections F to support the magazine and add rigidity by preventing lateral
movement.
Bolted or otherwise secured to the wall O, is an extension O", which is perforated
or provided with openings o in its sides, and whose lower extremity is formed with
inwardly projecting flanges upon which is supported the inner wall P of the
magazine. Arranged between the walls O and P, and extending the entire length
thereof, are partitions Q, preferably in the form of Z-shaped braces, which are
located in the four corners, dividing the space between the walls into four flues,
at the same time maintaining parity between the walls.
R indicates a downwardly-swinging trap-door, located at the fuel-magazine, whose
function is, to close the same to prevent the escape of the gases of combustion
when green fuel is introduced at the top of the magazine, and also to regulate an
up-draft through the magazine in starting the fire, as will be hereinafter described.
Connected to this trap-door, preferably on its under side, is a link R', to the other
end of which link is connected the inner end of an operating rod R", extending
through a way in the front water-section F and casing E. On the underside of
this rod R", is a lug or projection r, which rests on the inner side of the shell E
when the trap-door is closed, to hold the same in an elevated position. To cause
the trap-door to drop and discharge its supported fuel on to the fire on the grate-
bars, it is only necessary to raise the rod R", which releases the lug from the
casing E, and allows the rod R₁ to move outwardly, which is necessary in this
operation of the trap-door. To elevate the trap-door, the rod R" is forced
inwardly until its lug r. passes the casing. E and drops behind the same, which will
set the trap-door.
Leading from the interior of the magazine to the space above the water-head, is
a flue S, which is preferably closed' by a suitable damper S', through which the

page_text: products of combustion pass on first starting a fire. A pipe T also connects the
space from above the water-head to the stack. U is a damper in pipe T.
The operation of the heater is as follows:
Assuming that the fuel is laid and ready for ignition, the trap-door R is dropped,
opening a through-draft through the fuel-magazine, flue S, and pipe T, the
dampers S and U being opened. In this operation, oxygen is supplied to the fire
from the ash-pit, and the draft is entirely upward. After the fire has become
sufficiently started, the dampers S₁ and U are closed, and the trap-door R is
elevated. Green fuel is now placed in the magazine on the trap-door R, and,
when the magazine is full, the door M is placed in position. The draft-plates N
are now arranged to open the down-draft through the walls O and P. The trap-
door R is tripped, precipitating the green fuel on the fire, and, if desired, the
fuel in the magazine permitting, the trap-door can be again elevated. The course
now assumed by the products of combustion, the fire being principally fed by air
from the ash-pit, is to pass up along the sides of the magazine, and, intermingling
with the air from ports F" and opening o, substantially complete combustion will
take place. It will be noted that the products of combustion are compelled to pass
between two oppositely-inflowing streams of air, so that complete intermixture is
the result, followed by a thorough combustion. The gases then arise around the
fuel magazine, and along the inner faces of the water-sections (a considerable
number of heat units being absorbed by the heat-conducting pins), and, upon
reaching the top of the water-sections, they will pass around (above and below)
the water-head I, and thence downwardly outside of the water-sections to the
main-flue A under the boiler. The products of combustion return through the
boiler-tubes A into the breeching A" and out through the stack. It will be
seen from the above operation that a maximum number of heat units are absorbed
by the water-sections and water-head, and that complete combustion of the fuel is
accomplished, yielding the maximum heat from a given quantity of fuel. The
circulation of the water is as follows: Being admitted at the lower ends of the
sections, the heat will naturally cause it to rise and induce a circulation upward
through the pipes H into the water-head I, and, by pipe J, into the boiler A,
which is thus fed with water at a very high temperature. This causes the
efficiency the boiler to be constant, which would not be the result if cold water
were introduced at intervals in feeding the boiler, which would chill the same and
cause an irregular pressure. It will, also, be noted that the improved water-heater
as herein shown and described forms substantially a part of the boiler, covering
the entire front thereof, and that the heat generated for the heater is utilized for
the boiler.
When the apparatus is to be employed for generating and supplying steam at a
high tension, prefer to employ the construction shown in Figures 4 and 5, which
illustrate the application of the invention to a tubular boiler, as a locomotive
boiler for example. In these views :
Figure 4 is a longitudinal, vertical mid-section of the apparatus, the middle
portion of the boiler being broken away, and Figure 5 is a transverse vertical
section in the plane indicated by lines 5 and 5*, in Figure 4. That is to say, the
section at the right of Figure 5 is on line 5, and that at the left on line 5*.
A is an upper retort or coking chamber provided with a feed door, A' and a
dumping grate A2; B is a lower combustion chamber provided with a door B¹
and a grate B; and C an ash-pit. Extending over the top and sides of the
water-jacket D is a chamber or flue E; and over the front, sides and top of the
chamber or flue E is a chamber F more highly arched than the other chambers
to afford a steam space X; this chamber F is surmounted by a steam-dome X¹.
In the chamber E are flues E' extending from the ash-pit C to the level of the
top of the lower combustion chamber B, whence they pass through the water
jacket D to the chamber B just below the upper grate bars A*. Just above the
lower grate bars B³ are flues E' which extend from the combustion chamber B
and to the chamber E through the water-jacket D. Connecting the water-jacket

page_text: or chamber D and the chamber F, a little above the plane of the lower grate
bars B', are circulating tubes t t ; and circulating tubes t¹ connect the chambers D
and F, through the chamber E, at the crown or top. The outer water-jacket or
chamber F is open to the boiler G.
H is a flue-chamber with which the chamber or flue E communicates throughout
its entire end area above the tops of the flues E'; and extending downward in the
chamber His a hollow diaphragm or water leg H¹ which communicates at its
upper side with the chamber F. I is the rear tube-sheet of the boiler, and I' the
front tube-sheet, between which extend three series of flues s s¹ and s, respectively.
The tubes of the lower series s are comparatively large, say four inches in diameter;
the tubes of the central series s' are preferably somewhat smaller, say three inches
in diameter; and the tubes of the top series may be still smaller, say two and
one-half inches in diameter. In front of the tube-sheet I is a lower smoke-box
or chamber G', into which open the flues s s', and above the chamber G¹, and
separated from the latter by a diaphragm r, is an upper smoke-box or chamber G*
into which open the flues only. At the base of the chamber H is an opening o
provided with a damper o¹. Around the sides and lower part of the chamber H
is a water-jacket D', which opens at one end into the water-jacket D, and at its
opposite end into the boiler. The opening o extends through the water-jacket.
Between the diaphragm H and tube-sheet I is a damper p, at about the plane of
the lower end of the diaphragm, and the plane of division between the series, s and s',
of tubes. The smoke-box G* communicates with the smoke-stack, not shown.
Extending across the chambers F E to the chamber or water-jacket D is a feed
pipe Y. The pipe Y may be the feed pipe for the boiler and it may extend from
the water-tank, on the locomotive tender; a suitable injector being interposed in
the pipe. The water-jackets D and F and the boiler are filled and maintained
filled with water up to the water-line z, which is above the tops of the chamber E
and boiler tubes. Initially, the fire is built upon the grate bars B', and when
the combustion chambers become heated to a high degree, all further feeding of
fuel is done through the upper door A', the fuel being spread upon the upper
grates A and coked before it is dumped upon the lower grate.
The upper chamber is not only a preparatory chamber for heating the fuel
before it is introduced into the lower combustion chamber, but it is a retort
chamber into which no air is admitted to support combustion, so that the heat from
the lower chamber distils gas from the coal on the upper grate, the gas of distil-
lation passing through the upper grate bars to the chamber B. The fuel therefore
that is dumped upon the lower grate is more or less coked.
In practice air to supply combustion enters through the grate bars B¹ and
through the flues E'. The air passing through the flues E' mingles with the gases
from the chamber A which pass down through the fuel on the grate A³ to the
chamber B. The gases, as they descend into the chamber B and are carried down
by the air current from the flues E', are subjected to the heat in the latter chamber,
whereby substantially complete combustion of the gases is effected. From the
chamber B the products of combustion pass through the flues E to the chamber
and pass thence to the combustion chamber H. The diaphragm H₁ deflects the
products of combustion downward and causes them to pass below the damper p, and
through the lower series s of tubes to the smoke-box G', whence they pass through
the return tubes s to the part H³ of the chamber H, and thence through the
tubes to the smoke-box G and out at the smoke-stack. The heat from the
combustion chambers is communicated directly to the water in the chamber D, and
the heat of the products of combustion passing through the chamber E is
communicated to the chambers D and F. In passing to the chamber H the
products of combustion communicate then heat to the outer surface of the water-
jacket D, upon the water in the diaphragm chamber and in the water-jacket D¹;
and, in passing through the tubes, returning through the tubes 8, and passing
again through the tubes, approximately all of the heat of the products of com-
bustion is absorbed and utilized in heating the surrounding water. As the water

page_text: in the chamber D is heated it rises through the tubes t¹, water from the
chamber F entering the chamber D through the tubes t, whereby continued
circulation is kept up.
The products of combustion in passing from the chamber H through the lower
tubes s lose a certain proportion of their heat and become contracted in volume,
and they are still further contracted in passing through the second series of
tubes 8. Therefore by providing tubes s' of proportionately smaller diameter than
the tubes and tubes of still smaller diameter, an even draft is maintained
through the flues. Live cinders which are light enough to be carried through the
tubes of the draft will, owing to the distance of their travel be entirely consumed,
or lose their incandescence before reaching the chimney.
In my improved construction substantially all the available heating space is
utilized in making steam, and as all the walls with which the products of combustion
come into contact are surrounded by or in contact with water, the danger of injury
to the metal, forming the walls, from the heat is reduced to the minimum. By
feeding the furnace at the upper chamber the cooling influence of fresh fuel upon
the main fire bed B2 is avoided; and in the down draft of the more volatile gases,
substantially perfect combustion of the fuel is attained.
At suitable places, as at the base of the chamber F on opposite sides, and at the
base of the chamber F, draw-off cocks may be provided for draining out sediment
when desired. The draw-off cocks may be of any suitable form usually provided
for this purpose on other boilers.
Though my invention, as illustrated, is intended for use in connection with
boiler-furnaces adapted to generate steam at high pressure, it may be employed in
connection with steam-heating systems, where steam is generated at low pressure,
or in connection with hot-water heating systems. In either case the structure is
adapted to economize in fuel by utilizing the heat therefrom to an extent beyond.
the capacity of furnaces hitherto constructed for the same purpose.
While I prefer to construct my improvements as shown and described, they
may be modified in the matter of details without departing from the spirit of my
invention.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I claim :-
1. In water-heating and steam-generating apparatus, a fuel magazine consisting
of hollow walls, partitions dividing the hollow in the walls into draft flues, means
for regulating the influx of air to the upper ends of said flues, and perforations in
the outer wall of the magazine near its lower end for the escape of air therefrom,
substantially as set forth.
2. In water-heating and steam-generating apparatus, the combination with a
suitable shell or casing, of water sections arranged therein, grate-bars, and a
fuel-magazine located above the grate-bars, said fuel-magazine consisting of an
outer and an inner wall, said outer wall having a projecting flange at its lower
edge upon which the inner wall is supported, substantially as set forth.
3. In water-heating and steam-generating apparatus, the combination with a
suitable shell or casing, of grate-bars, water-sections arranged around said grate-
bars, a fuel-magazine arranged above the grate and between the water-sections,
said fuel-magazine being formed of walls between which an air-flue is formed,
which discharges above the grate-bars, pipes which lead to all of said water-sections,
a water-head arranged above the sections and a connection between the water-head
O and each of said sections, as set forth.
4. In water-beating and steam-generating apparatus, the combination with
water-sections formed with heat-conducting pins on their inner faces, of a belt
pipe which leads to all of said sections, a water-head arranged above the water-
sections and a connection between the water-head and each of said sections,
5 substantially as set forth.
5. In water-heating and steam-generating apparatus, the combination with a

page_text: suitable shell, of 'a grate, water-sections arranged around said grate, a fuel
magazine located above the grate, and forming an up draft flue in connection with
the water-sections, said fuel-magazine being composed of two walls, between. which
is formed a down draft flue opening into the upper draft flue.near the bottom of the
magazine, and ports which open into the ash-pit and discharge into the up-draft
flue, substantially as set forth.
6. In water-heating and steam-gennerating apparatus, the combination with
the grate, of water-sections arranged around said grate, a fuel-magazine formed
with flues inducing oxygen and supporting combustion above the grate-bars, said
water-sections containing air-ducts and ports therein, said ports opening into the
combustion chamber opposite the point of discharge of the magazine-flues,
substantially as set forth."
7. In water-heating and steam-generating apparatus, the combination with a
suitable shell or casing and a grate, of water-sections arranged around said grate
and forming a combustion chamber thereabove, a fuel-magazine which is located in
the combustion chamber, said magazine being formed with air-flues leading from
the exterior which discharge into the combustion chamber and flues which open
into the ash-pit and discharge into the combustion chamber substantially in an
opposite direction from the discharge of the air from the magazine-flues, substantially
as set forth.
8. In water-heating and steam-generating apparatus, the. combination with a
suitable shell or casing, of a grate, water-sections arranged above the grate, a fuel-
magazine situated above the grate, a downwardly swinging trap-door located in
said fuel-magazine, a link attached to the outer side of said trap-door, an operating
handle which is connected to said link and which extends out through the shell, and
means on said handle for retaining.the door in an elevated position, substantially
as set forth.
9. In water-heating and steam-generating apparatus, the combination with an
euclosing shell or casing, of a grate and water-sections located therein, a fuel-
magazine above the grate between which and the water-sections is formed an up-
draft flue, and between the water-sections and shell is formed a drum draft flue, a
trap-door damper located in the fuel-magazine, a flue S which leads from the top of
the magazine, and a pipe T which leads from the top of the casing or shell to a
stack, substantially as set forth.
10. In water-heating and steam-generating apparatus, the combination with an
enclosing shell, of a grate, water-sections arranged above the grate, pipes leading
to the several water-sections, a water-head which is connected to the several sections
by pipes, and a tubular boiler to which the water-head is connected, and through
which tubular boiler the products of combustion pass from the grate, substantially
as set forth.
11. In water-heating and steam-generating apparatus, the combination with an
enclosing shell, of a grate situated therein, water-sections situated above the grate,
between which water-sections and the shell is formed a down draft flue which opens
into a flue beneath a tubular boiler, a fuel-magazine which is located above the
grate-bars between which magazine and the inner walls of the water-sections is
formed an up draft flue which connects with the down draft flue above the water-
sections, and said tubular boiler, through which the products of combustion pass,
substantially as set forth.
12. In water-heating and steam-generating apparatus, the combination with an
enclosing shell, of a grate, water-sections situated above said grate, between which
and the shell is formed a down draft flue which opens into a draft flue beneath a
tubular boiler, a fuel-magazine situated above the grate, between which and the
water-sections is formed an up draft flue which connects with the down draft flue,
at the top of the water-sections, the said tubular boiler, a stack for said boiler, and
a pipe T provided with a damper, which leads into said stack from above the water-
sections, substantially as set forth.
13. In water-heating and steam-generating apparatus, the combination of a
::

page_text: combustion chamber B, provided at its bottom with a grate B2, an inner, water-
acket D, extending over the top and sides of the chamber B, a flue chamber E
extending over the top and sides of the inner water-jacket, outlet flues E³, extending
between the lower parts of the chambers B and E, air-inlet flues in the chamber E.
extending from below the grate B and opening into the chamber B towards the top
thereof, an outer water-jacket F, extending over the sides and top of the chamber E,
and circulating flues t, t¹ extending between the said outer and inner water-jackets
toward the lower and upper parts of the latter, all constructed and arranged to
operate substantially as described.
a
14. In water-heating and steam-generating apparatus, the combination with the
combustion-chamber, of a chamber B, a flue extending from the combustion-chamber
to a chamber H, a chamber H2, a separating wall between the chambers H and H',
boiler.
chambers G' and G³, a dividing-wall between the chambers G1 and G2,
extending between the chambers H, H³, and the chambers G', G', provided with a
lower series of tubes & extending between the chambers H and G¹, an intermediate
series of return tubes s', of smaller diameter than the tubes s, extending between
the chambers G' and H³, and an upper series of tubes s of smaller diameter than
the tubes 1, extending between the chambers H' and G³, substantially as
described.
15. In water-heating and steam-generating apparatus, the combination of a.
combustion-chamber, an inner water-jacket D extending over said chamber, a flue
extending from said chamber around the inner water-jacket, a chamber H with
which the flue communicates, a boiler G, having tubes extending between the
chamber H and a chamber G¹, between the chamber G' and a chamber H2 and
between the chamber H' and a chamber G, an outer water-jacket extending over
the flue E and chambers H, H2, and communicating with the boiler G, and
circulating conduits between the inner and outer water-jackets, substantially as
described.
16. In water-heating and steam-generating apparatus, the combination of an
upper coking chamber A, having a feed door, a lower combustion-chamber B, a
dumping-grate between said chambers, an inner water-jacket D, extending over
said chambers, a flue E extending from the said lower chamber around the inner
water-jacket, a chamber H, to which the flue extends, a boiler G, having tubes 8,
extending from the chamber H to a chamber G', tubes extending from the
chamber G¹ to a chamber H³, and tubes s' extending from the chamber H2 to a
chamber G³, an outer water-jacket extending over the flue E and chambers H, H',
and communicating with the boiler G, a hollow diaphragm H' having a water-
chamber F', between the chambers H and H2, and circulating conduits between the
inner and outer water-jackets, substantially as described.
Deted the 27th day of May 1895
STEPHEN WATKINS,
Wolverhampton, Agent for the Applicant.