Improvements in and Connected with Steam Boilers and Furnaces for Steam Boilers and other Purposes.
Year: 1886

page_text: Date of Application, 12th Aug., 1886
Complete Left, 12th May, 1887.
Complete Accepted, 29th July, 1887
Improvements in and Connected with Steam Boilers and Furnaces
for Steam Boilers and other Purposes.
I THOMAS LISHMAN of 66, West Street, Gateshead, in the county of Durham,
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in and connected with steam boilers and
boiler furnaces and furnaces for the heating and manufacture of iron and steel or for
other metallurgical purposes the invention having for object to effect a more complete
combustion of the fuel and obtain greater heat therefrom and to effect economy.
According to my invention I construct the boiler by preference cylindrical, and I
place therein one or more flues which I utilize to form the furnace or furnaces, the said
Hues are constructed by preference with external flanged jointings and cross pipes, or
tubes are arranged therein and secured by external flanges to the said flues or welded
into the same.
The gases generated in the hereinbefore described furnace or furnaces are conveyed
by means of one or more pipes to a combustion chamber or chambers; the said
combustion chamber or chambers being by preference placed horizontally lengthwise
of the flue or flues or furnace or furnaces instead of vertical as has hitherto generally
been the case; communication can be effected between the flues and combustion
chambers and the outside of the boiler by means of tubes which also serve as stays or
supports for the flues and combustion chambers; the said tubes are provided with
suitable doors or covers; from the said combustion chamber or chambers the
superfluous gases escape by means of one or more connecting pipes through a water
receiver placed in any suitable position on or near the boiler; a perforated plate is

page_text: fixed in the said receiver and a pipe is provided for the escaping gases, by these means
the feed water becomes heated by the escaping gases before entering the boiler, and all
smoke is consumed and therefore no chimney is required.
The front portion of the hereinbefore described flue or flues, or furnace or furnaces
forms the fuel chamber, and I place therein one or more sets of tubes; the said set or
sets of tubes consists or consist of one tube placed concentrically within another the
space between the two tubes forming a water space; through the said space pass small
transverse pipes or tubes forming air inlets to the fuel. One end of the tubes is
secured to a plate and can be provided with an air regulating slide or valve or its
equivalent, the said plate being attached to and forming part of the bridge which can
be made hollow so as to form an air receiver, the front end of the tubes is attached to
a moveable blast pipe having a suitable regulator for supplying the required quantity
of air from a fan blast or the like to the fuel; by this means the use of fire bars or
grates is entirely dispensed with; the front of the fuel chambers may be entirely
closed by means of moveable doors the combustion being produced by the said blast
or forced draught.
The herein before described arrangement of furnace or furnaces is also applicable to
existing boilers.
In some cases however when applying my improvements in furnaces to boilers of
ordinary construction I make use of fire bars, by preference placed transversely across
the furnace and can dispense with the blast or not; in either case I employ the herein
described concentric tubes to deliver air into the air receiver or bridge, the said air
receiver being provided with a number of orifices through which the highly heated air
passes into the combustion chamber or chambers and assists in perfecting the gases
therein. When the bridge is made hollow I provide the front moveable doors with air
regulating inlets.
In the boiler I provide a pipe of much larger area at its upper part than at its lower
part and a circulating water pipe curved at its upper end; the former of the said pipes
extends from the steam space downwards to the bottom of the boiler and the end of
the other pipe dips below the level of the water line in the boiler. By this
arrangement the steam is forced down the first named pipe and causes a constant
agitation and heats the water in the lower part of the boiler which by this means assists
in causing the water to ascend in the curved pipe a constant circulation being thereby
kept up and accumulations or deposits on the surface of the boiler prevented.
For iron or steel making or heating I construct the furnace with an externa leasing
which may be of cast iron and lined or partially so with fire brick or other heat
resisting material but by preference I employ an internal and external shell or casing
with a space between forming an air channel around the body of the furnace and
communicating with an air receiver as hereinbefore described. Air channels also pass
under the floor of the furnace the said channels delivering into the air receiver the air
being supplied by a blast or otherwise; from the air receiver the air is caused to travel
through the walls of the fuel chamber, the said fuel chamber can be provided on all
sides with an iron casing having water spaces and air inlets; a portion of the air is
admitted in regulated quantities underneath the fuel chamber and a portion passes all
around and above the fuel and bridge, the whole forming a complete gas generator.
For obtaining a supply of air by artificial means I construct an apparatus consisting
of a piece of ordinary steam piping or other suitable tubing of the required diameter
and area.
I provide a cone or tapered piece the aforesaid pipe and the head of the
cone being connected together by an external box screwed on to each. The head of
the cone has one or more small openings for the admission of steam; the steam as it
enters strikes the said conical part and is protected by the walls of the external box
by which means momentum is obtained and noise diminished. The steam inlet is
regulated by a valve attached to the pipe.
For gas generating purposes I sometimes construct a furnace on the vertical principle
but operating in a similar manner to those herein before described the gas outlet being
placed at the upper part of the apparatus and conveyed by conduits to the boilers or
furnaces to be supplied, air being admitted to the same as before described,

page_text: For iron and other manufacturing purposes I place in any convenient situation a
vertical boiler heated by the gases from the furnace or furnaces, the said boiler being
formed with internal and external water chambers the space between the two water
chambers forming a passage for the gases which are thereby caused to operate on both
water chambers, the gases escape into a gas receiver placed on the upper portion of
the boiler and thence pass to the chimney; a connection, and a circulation of the
water between the external and the internal parts is obtained by means of pipes
attached thereto, the said pipes being provided with the necessary valves for regulating
purposes.

page_text: for Steam Boilers and other Purposes.
1, THOMAS LISHMAN, of 66, West Street, Gateshead, in the county of Durham,
Engineer, 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 improvements in and connected with steam boilers and
boiler furnaces and furnaces for the heating and manufacture of iron and steel or for
other purposes, the invention having for object to effect a more complete combustion
of the fuel and obtain greater heat therefrom and to effect economy. Parts of the
said improvements are applicable to existing steam boilers.
In order to enable my invention to be fully understood 1 will describe how the
same can be carried into practice by reference to the accompanying drawings in
which figure 1 represents a front elevation of a pair of horizontal boilers adapted to
work at high pressure and constructed according to my invention. Figure 2
represents a longitudinal section of the same on the crooked line A B of figure 1.
Figure 3 represents a transverse section drawn to a larger scale, of one of the flue
tubes and fuel beds hereinafter described, the section being taken on the line C D of
figure 2. Figure 3*, represents a longitudinal section of the flue tube of a boiler
similar to that shewn in figures 1 and 2, but provided with a modified form of fuel
bed. Figure 3b represents a section taken on the line C, D', of figure 3. Figures 3º,
3d, and 3, represent respectively a longitudinal vertical section, a horizontal section,
and a transverse vertical section of a furnace, constructed according to my invention,
for iron or steel making or heating. Figure 4 is a longitudinal section of part of a
boiler with air receiver or chamber and arranged to work at a high pressure by means
of my air injector shewn in figure 7; figure 5 is a front view of the same, and
figure 6 is a back view of the air receiver and bridge; figure 7 is a sectional view of
the injector; Figure 7, represents a vertical section of a furnace constructed according
to my invention for generating gas from combustible fuel. Figure 7 represents a
horizontal section taken on the line G H of figure 7. Figure 8 is a vertical section
shewing my improved boiler adapted for use with a mill or forge furnace and arranged
to be heated by the gases escaping therefrom; figure 9 is a plan half in section the
section being taken on the line E F of figure 8; figure 10 is a vertical section of a
marine boiler having one of my fuel beds applied thereto in place of the ordinary fire-
bars. Similar letters in all the figures represent similar or corresponding parts.
Referring to figures 1 to 3 I construct the boilers by preference cylindrically as
shewn and in each I place two flues a, a, (or one or any other number can be used).
These flues I utilize to form the furnaces; the said flues are constructed by preference
with external flanged jointings b, b, and cross pipes or tubes c, c, are arranged therein
and secured by external flanges d, d, to the said flues or they can be welded into
the same.

page_text: The gases generated in each of the hereinbefore described furnaces a, a, are con-
veyed by means of one or more pipes e, e, to a combustion chamber f, (or chambers)
the said combustion chamber being by preference placed horizontally lengthwise of
the flues or furnaces a, a, instead of vertically as has hitherto generally been the case:
communication is effected between the flues a, a, and the outside of the boiler by
means of tubes (one of which is shewn at g, in figure 2) which also serve as stays or
supports for the said flues; each of the tubes g, is provided with a suitable door or
cover gl, as shewn. The rear end of each of the combustion chambers f, ƒ, is
provided with a door f¹, and I can also arrange at the said end an air injector
similar to that hereinafter described and shewn in figure 7 so as to blow air into the
combustion chamber for more thoroughly effecting combustion; from the said com-
bustion chamber, the superfluous gases escape by means of a connecting pipe h,
through and into a feed-water receiver i, placed at the front of each of the boilers as
shewn or in any other suitable position on or near the boiler. The portion of the
pipe, inside the water receiver i, is perforated to within a short distance of its upper
end and is surrounded by another pipe j, which is perforated only at its upper end.
The upper ends of both the pipes, and j, are closed by a conical plate k; a T-shaped
pipe 1, is provided to carry off the escaping gases from each of the receivers i, i, by
these means the feed-water becomes thoroughly heated by the escaping gases before
entering the boilers, and all smoke is consumed and therefore no chimney is required;
w, w, are the pipes for conducting the feed water to the boilers as hereinafter
described.
The front portion of each of the flues or furnaces forms the fuel chamber and I place
therein one or more sets of tubes, only one set m, n, being shewn in each of the
flues a; the said set of tubes which forms a bed for the fuel consists of a tube m,
placed concentrically within another tube n, the space between the two tubes forming
a water space o, which is connected with the interior of the boiler by a pipe z ;
through the said space o, pass small transverse pipes or tubes p, forming air inlets to
the fuel as shewn clearly in figure 3. One end of the outer tube n, is secured to a
plate q, the said plate being attached to and forming part of the bridge r, which is
iuade hollow so as to form an air receiver; the front end of each of the tubes m, m, is
attached to a moveable blast pipe 8, having a suitable regulator or valve t, and
attached to an air channel s¹, by sockets, the air channel s', supplying the required
quantity of air from a fan blast or the like to the fuel by means of the pipes 3, 3, and
fuel beds m, n, m, n; by this means the use of fire bars or grates is entirely dispensed
with; an air pipe u, supplied from the said fan blast conducts air to each of the air
receivers r, r, whereby a supply of oxygen is furnished through orifices v, v, to the
escaping gases as they pass from the fuel chambers over the bridges to the combustion
chambers ff; the front of the fuel chambers may be entirely closed by means of
moveable doors, not shewn in the drawings, the combustion being produced by the
said blast or forced draught; w, is a feed pipe for supplying the boilers with the
water contained in the receivers i, i, by means of a feed pump not shewn in the
drawings. The feed pipe wo, is provided with suitable valves, x, and blow off
cocks y, y, and is connected by branches to the outer ends of each of the water
spaces o, o, so that the feed water is caused to circulate through the whole length of
the fuel beds thereby increasing in temperature before passing through the pipes =,=,
into the boilers.
In some cases I connect the boiler with the pipe w, by means of a pipe, shown in
dotted lines in figure 1, by which means in conjunction with the pipe z, a circulation
is maintained in the water spaces o, o, and in the boiler and the water is supplied to
the boiler at a very high temperature. The pipe, however will not be required
when the water to the boiler is supplied by gravitation and escapes by an overflow
pipe or when the said water is forced through the pipe w, and water space o.
Instead of constructing my fuel bed as just described I sometimes construct it as
shewn in figures 3*, and 36, that is to say, I provide two rectangular or circular
tubes n, n, closed at each end and forming water spaces o, o, and arrange them with
an air space m, between them as shewn.

page_text: Short transverse pipes p, p, similar to those in figures 1 to 3 are arranged
through the tubes n, n, so as to allow of the air blast, which is forced into the air
space m, through the pipe s, passing through into the fuel in the direction of the
arrows in figure 3b.
When a number of furnaces are worked conjointly the pipes w, w, and z, z, are
provided with automatic equilibrium valves (not shewn in the drawings) so as in case
of accident to any furnace to allow of the water circulation in such furnace being
stopped without interfering with the circulation in the remaining furnace or furnaces.
The feed pipe to, is connected to one end of each of the tubes n, n, the circulating
water passing off at the other end through the pipe z, which is also connected to each
of the said tubes. Instead of the bridge r, being fed with the air blast through a
separate pipe as in figures 1 and 2 it is connected to one end of the air space m, for
that purpose as shewn.
When applying my fuel beds to existing or ordinary boilers, instead of placing the
circulating pipes z, z, in the interior of the boiler as hereinbefore described I may
place them outside as shewn by the dotted lines in figures 1 and 2.
For iron or steel making or heating I make use of the furnace shewn in figures 3º, 3d,
and 3-This furnace I construct with an external casing a', which may be of cast
iron and lined (or partially so) with fire brick 6, or other heat-resisting material. Air
channels c, c, pass under the floor d², of the furnace, the said channels c³, c³, delivering
into the air receiver or bridge r, the air being supplied by a blast or otherwise through
an air channels; from the air receiver r, the air is caused to travel through the walls
of the fuel chamber a; the said fuel chamber being provided at the sides, back, and
bottom with an iron casing m, n, having water spaces o, o, and air inlets p,p; a portion
of the air is admitted in regulated quantities underneath the fuel chamber
and a
portion passes all around and above the fuel and bridge r, as shewn by the arrows,
One or
thereby producing complete combustion.
more doors, not shewn in the
drawing, are provided to allow of the furnace being charged with the ore or other
material to be treated; d³, is the fire door and d the ash pit door.
a,
Figures 4, 5, and 6, illustrate the application of my improved air injector to a boiler
furnace in which ordinary fire bars a¹, a', are employed, some of the bars being by
preference placed transversely across the furnace; in this case I employ a tube u (or
tubes) to deliver air into the air receiver or bridge r, the said air receiver being provided
with a number of orifices v, v, similar to those hereinbefore described and shewn in
figure 2 and with a perforated pipe 6', through which the highly-heated air passes into
the combustion chamber or chambers and assists in perfecting the gases therein. The
ash pit and fire chamber are closed in and supplied with air by a blast or steam jet
forced in from the back end of the flue. Figure 7 shews a section of the injector.
In constructing this injector I provide a piece of ordinary steam piping c², or other
suitable tubing of the required diameter and area. I also provide a cone or tapered
piece d', enclosed in a conical casing e¹, the aforesaid pipe c¹, the head of the cone d³,
and the conical casing e¹, being connected together by an external box or ferrule h¹,
screwed on to each. The head of the cone d₁, has one or more small openings a, a,
for the admission of steam and placed at an angle so that the steam as it enters strikes
the said cone d, and is conducted by the conical casing e¹, to an air pipe 2, thereby
inducing a current of air in the direction of the arrows. By this arrangement
momentum is obtained and noise diminished. The steam inlet is regulated by a
valve, attached to the pipe c'.-To the air channel s¹, I attach a pipes, by means of
a joint or sockets, somewhat similar to the arrangement shewn in figures 1 and 2, so
that the said pipe (to which is fixed the cover k', of the opening to the fuel chamber)
can be rotated on the said joint when access is required to the fuel chamber.
For gas generating purposes I make use of the furnace shewn in figures 7", and 7.-
This furnace I arrange on the vertical principle and construct it with an external metal
casing a², lined with fire brick in a similar manner to that hereinbefore described with
reference to figures 3º, 3d, and 3º.
The casing a, is mounted on a base plate &, and secured thereto by bolts and
nuts In the centre of the furnace and fixed to the base plate e³, is a hollow

page_text: truncated cone 93, formed of a casing of metal covered with fire brick. Around the
cone g², is placed the fuel from which the gas is to be produced, air being supplied
through inlets p, p, a hit-and-miss (or other) regulator, at the base of the cone g³,
being used to regulate the supply of air to the fuel, the said supply being regulated so
as to allow of the combustion only of a small portion of the gas contained in the fuel,
the remaining portion of gas generated passing away unconsumed; 2, is a pipe with
a perforated end, through which air is forced from a blast so as to mix with the
unconsumed gas, the combined air and gas passing away through the gas outlet *,
which is placed at the upper part of the apparatus, the said air and gas being con-
veyed by conduits to the boilers or furnaces to be supplied; d³, is the door through
which the furnace is charged with fuel and d', d, are doors through which the
ashes can be raked out, or the ashes and debris can be more effectually cleared out
by unscrewing the bolts 2, and 3, and then raising the casing a, with the pipe ›².
Figures 8 and 9 illustrate my improved construction of vertical boiler to be heated
by the waste gases from a furnace or furnaces used for the manufacture of iron
or for other manufacturing purposes. The said boiler is formed with internal and
external water chambers 1, and m', respectively, the space f, between the said water
chambers forming the combustion chamber or passage for the said waste gases
which enter the boiler at the lower part thereof and are caused to operate on both
water chambers. The said gases escape by means of tubes o¹, o¹, into a gas receiver p¹,
placed on the upper portion of the boiler and thence pass to the chimney q'; a con-
nection and a circulation of the water between the external and the internal parts
is obtained by means of pipes t¹, and r¹, rl, attached thereto the pipes r, r', being
provided with the necessary valves u', u', for regulating purposes.
Figure 10 represents a marine boiler from which the ordinary fire bars have
been removed, one (or more) of my fuel beds, constructed in the manner shewn in
figures 1 and 2, being employed in place thereof, or I may use one or more of
those herein before described and shewn in figures 3*, and 3b.
All the principal parts of the hereinbefore described boilers are preferably made
of steel or malleable iron plates without being rivetted and they will therefore
withstand a much greater pressure than steam boilers of ordinary construction. They
can if required be constructed without internal stays, easy access can be had to all
parts, and the parts can be easily detached without injury for the purpose of
examination or repairs.
By the use of my improved boilers and apparatuses which are simple in construction
and inexpensive, a great economy is effected in the consumption of fuel as any quality
of fuel including liquid fuel can be employed, the feed water is heated and steam is
rapidly generated. By my improvements I am also able with a generator of small
size to obtain better results than with one of much larger size as hitherto generally
constructed.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed I declare that what I claim is :-.
1. In a steam boiler the arrangement of the flues a, a, and f, for the purposes
herein before described and as represented by figures 1 and 2 of the accompanying
drawings.
2. The use in combination with a steam boiler of a feed water heater consisting of
pipes h, and j, arranged in a receiver i, wherein the water is heated by the escaping
gases from the boiler substantially as hereinbefore described and illustrated in figures I
and 2 of the accompanying drawings.
3. In a steam boiler the combination with the fuel chamber or chambers of the
boiler, of tubes m, placed concentrically within other tubes n, water spaces being left
between them and air conducting pipes p, forming a communication between the inner
tubes and the fuel chamber substantially as and for the purposes herein before described
and illustrated in figures 1, 2, and 3, of the accompanying drawings.
4. The arrangement herein described for connecting the concentrically formed
tubes
to the boiler and feed water source, such arrangement consisting of
and
m,
n,

page_text: the pipe w, having valves a, x, and the tube, z, the whole serving as an additional
heating medium for the boiler substantially as hereinbefore described and illustrated
in figures 1 and 2 of the accompanying drawings.
5. In a steam boiler the combination with a hot air receiver of an air-conducting
pipe u, placed in the bed of the fuel, the heated air being delivered into the flues a, a,
for generating the gases at v, substantially as hereinbefore described and illustrated
in figures 1 and 2 of the accompanying drawings.
6. The combination with a steam boiler of the arrangement for heating the feed
water and feeding the same to the boiler, the said arrangement consisting of the feed
pipe w, water space 0,
and pipes, and 23, substantially as herein before described and
illustrated in figures 1 and 2 of the accompanying drawings.
7. The modified arrangement of tubes m, and n, substantially as hereinbefore
described and illustrated in figures 3ª, and 3b, of the accompanying drawings.
8. The construction and use in combination with a steam boiler of a steam air
injector having a cone or tapered piece the head of which is provided with openings
therein and connected to a conical casing and the steam pipe by an external box or
ferrule substantially as hereinbefore described and illustrated in figures 4 and 7 of the
accompanying drawings.
9. The construction of vertical boiler arranged to be heated by the waste gases from
the furnace or furnaces used for the manufacture of iron or for other manufacturing
purposes substantially as herein before described and represented in figures 8 and 9 of
the accompanying drawings.
10. The use in combination with a vertical steam boiler of concentric tubes m, n,
pipes p, z, and h³, substantially as hereinbefore described and represented in figure 10
of the accompanying drawings.
11. The improved steam boilers herein before described and represented in the various
figures of the accompanying drawings.
12. The improved furnaces for iron or steel making or heating and for gas generating
purposes hereinbefore described.
M1007