Improvements in or connected with Self-contained Gas-fired Steam Generators.
Year: 1889

page_text: Date of Application, 16th Sept., 1889
Complete Specification Left, 16th June, 1890-Accepted. 16th Dec., 1890
PROVISIONAL SPECIFICATION.
Improvements in or connected with Self-contained Gas-fired Steam
Generators.
1, JOHN JACKSON, of Chapel Chambers South, 28, Chapel Street, Liverpool, in the
County of Lancaster, Engineer, do hereby declare the nature of my said invention to
be as follows:-
This invention relates to gas-fired steam generators of the type described in the
Specification of my Application for Letters Patent No. 5146 of 1889, that is to say, a
steam generator consisting as a whole of a combined gas producer, combustion
chamber and water and steam containing vessel, forming practically one structure.
According to the present invention, I so construct steam generators of the above
mentioned type, which have vertical heating tubes, (i.e. of the vertical multitubular
type), that the tubes were acted upon by the gases of combustion, are wholly covered
or surrounded with water and without sacrifice of length of tubes.
One way of constructing such steam generators, is by providing a tube plate in
which the tubes are secured in the upper part of the generator, and which lies below
the water level. The tubes lead into a waste gas chamber, which may lie wholly
below the level of the water, or partly below and partly above such level; this
chamber may be arranged to lie laterally outside the central steam space or chamber, or
within an outer one.
If the generator is provided with a nest or nests of tubes outside a central or inner
gas producer, the waste gas chamber may be an annular one, the space within it being
a central or inner steam space, and vice versa.
According to one form of steam generator I provide a central gas producer, having
a nest or nests of tubes around it, and the gases may be led by a downtake pipe or
pipes from the upper part of the producer to a gas chamber, and then into a com-
bustion chamber outside it, and lying about, or in the base thereof; or the gases
according to another arrangement may be led upwards and then down to the said
chambers.
In the combustion chamber air is supplied to support combustion of the gases, and
this air is first heated by passing it through suitable passages round or in the brickwork
of the chamber and its casing, so that it may be well heated before coming in contact
with the gases. To ensure good combustion, I prefer to lead the air into a chamber
or chambers provided with holes or apertures so as to distribute it and make it mix
thoroughly with the gases, which are also preferably divided and distributed into thin
streams or jets by like or corresponding holes or apertures provided in the wall of the
gas chamber.
The distributing air and gas chambers are preferably arranged along the whole
length, or a greater part thereof, of the combustion chamber, and by this arrangement
an equal distribution of the gases of combustion takes place through the whole of the
tubes, thus all available beating surface is made use of, and equally, and a consequent
large evaporative efficiency will be obtained.
These jets or streams of air and gas, issue preferably in opposing directions so that
they combine and mix effectively.
According to one mode or modification of the arrangement of the gas producer
combustion chamber and tubes, the producer may be arranged eccentrically.

page_text: may employ in connection with the gas producer a grate adapted to be rotated
and provided with bars or a bed so constructed that the clinker and other solid refuse
may be worked automatically towards the outside and thrown out, and if desired into
a suitable receptacle.
One form of grate to effect this may be provided with projecting parts spirally
arranged.
To regulate the supply of gas and air, 1 provide a valve or valves in or in
connection with the air and gas conduits by which the proper proportions may be
maintained at all rates of firing, and this is preferably done by providing a single
actuating device by which the air and gas passages are simultaneously or together
more or less opened and closed. This device (or devices as the case may be) may be
disposed at any convenient place or places on the generator. This portion of my
invention may be very conveniently arrange and used in connection with the
eccentric arrangement of producer; and in this case a single gas conduit may be
conveniently employed, but at the same time, a plurality of such conduits may be
employed if desired.
In cases where desirable I provide an automatic fuel feeding device, which conveys
the fuel from a receptacle or hopper, and discharges it into a passage or shoot leading
into the interior of the producer above the fuel level. One arrangement of this may
consist of a closed receptacle in which a worm or bucket or like elevator conveys the
fuel out of the receptacle and discharges it into the feeding shoot or passage. The
elevator may be operated by a small steam engine, or from any suitable moving
part, which, if a revolving and self cleaning grate be used, may also operate said
grate.
It must be understood that the construction and arrangements of parts herein
mentioned or described, may be modified and used in various ways and com-
binations without departing from the essential features or spirit of the invention.
Dated this 13th day of September 1889.
CHEESBROUGH & ROYSTON,
Applicant's Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with Self-contained Gas-fired Steam
Generators.
1, JOHN JACKSON, of Chapel Chambers South, 28, Chapel Street, Liverpool, in the
County of Lancaster, Engineer, do hereby declare the nature of this invention and
in what manner the same is to be performed, to be particularly described in and by
the following statement:-
This invention relates to gas fired steam generators of the type described in
the Specification of my Application for Letters Patent No. 5146 of 1889, that is
to say, a steam generator consisting as a whole of a combined gas producer,
combustion chamber, and water and steam containing vessel, forming practically
one structure.
According to the present invention, I so construct steam generators of the above
mentioned type which have vertical heating tubes, (i.e., of the vertical multi-
tubular type), that the tubes were acted upon by the gases of combustion, are
wholly covered or surrounded with water, and without sacrifice of length of tubes.
One way of constructing such steam generators, is by providing a tube plate in
which the tubes are secured in the upper part of the generator, and which lies below
the water level. The tubes lead into a waste gas chamber, the bottom of which may
lie wholly below the level of the water, or partly below and partly above such level;
this chamber may be arranged to lie laterally outside a central steam space or chamber,
or within an outer one.
If the generator is provided with a nest or nests of tubes outside a central or inner

page_text: gas producer, the waste gas chamber may be an annular one, the space within it being
a central or inner steam space, and vice versa.
According to one form of steam generator, I provide a central gas producer,
having a nest or nests of tubes around it, and the gases may be led by a downtake
pipe or pipes from the upper part of the producer, to a gas chamber, and then
into a combustion chamber outside it, and lying about, or in the base thereof; or
the gases according to another arrangement may be led upwards and then down to the
said chambers.
In the combustion chamber air is supplied to support combustion of the gases, and
this air is first heated by passing it through suitable passages round or in the brick-
work of the chamber and its casing, so that it may be well heated before coming in
contact with the gases. To ensure good combustion, I prefer to lead the air into a
chamber or chambers provided with holes or apertures so as to distribute it, and make
it mix thoroughly with the gases, which are also preferably divided and distributed
into thin streams or jets by like or corresponding holes or apertures provided in the
wall of the gas chamber.
The distributing air and gas chambers are preferably arranged along the whole
length, or a greater part thereof, of the combustion chamber, and by this arrangement
an equal distribution of the gases of combustion takes place through the whole of the
tubes, thus all available heating surface is made use of, and equally, and a consequent
large evaporative efficiency will be obtained.
These jets or streams of air and gas, issue preferably in opposite directions so that
they combine and mix effectively.
According to one mode or modification of the arrangement of the gas producer and
combustion chamber and tubes, the producer is arranged eccentrically within the shell
of the generator.
In the drawings, which serve to illustrate an example of steam generator according
to the invention, I give a self contained gas fired steam generator in which the gas
producing furnace is eccentrically arranged in the water containing vessel, and
wherein the above described construction, by which the heating tubes are wholly
covered with water, is provided.
The same letters and figures of reference are used throughout the views to denote
the same or corresponding parts.
Figure 1 is a sectional elevation of the generator through the gas furnace and
combustion chamber.
Figure 2 also shews the generator in vertical section, but such section is taken at a
point at right angles to that at which the view in Figure 1 is taken.
Figure 3 is a plan taken through the generators, half at the line Y. Y. and half at
the line Z. Z. in Figure 1; and
Figure 4 is a plan viewed from the top.
Referring to the drawings; A is the gas producer which is arranged in the shell of
the generator eccentrically; B is the said generator shell; C is the combustion
chamber disposed below the gas producer and directly underneath the lower tube
plate; D is the chamber to which the gases produced in the furnace A are conveyed
prior to delivery to the combustion chamber C; E is the downtake pipe or tube by
which said gases are conveyed from the gas furnace A to the chamber D; F is the
chamber or conduit to which the heated air used to support combustion of the gases
is conveyed, prior to its introduction into the combustion chamber; d¹ and flare the
narrow apertures in the walls d' and 2, separating the gas chamber D, and hot air
chamber or conduit F, respectively, from the combustion chamber, by which the gas
and heated air are distributed and flow from said chambers into the combustion
chamber, and by which such air and gas in their flow into the combustion chamber
are caused to meet one another, and become thoroughly mixed, and complete com-
bustion facilitated; G is the case enclosing the aforesaid chamber in the lower
portion of the structure; H is the inlet having the governing valve h¹, and H' are
pipes through which the air, subsequently used to support combustion of the gases
generated in the producer within the combustion chamber, enters the casing G; I, are

page_text: the passages between the wall f' and the case G, which convey the air from the
pipes H to the chambers or conduits F, and in which the air is heated by the heat
which passes from the combustion chamber through the wall 2; and it is a hori-
zontal partition by which the passage I and the chamber or conduit F, are
separated.
2
The walls f¹, d² and d are of suitable firebrick or fire resisting material, and
the bottom of the chambers C and D are also lined with the same materia!.
With regard to the upper parts of the generator, K. is the steam dome or vessel ;
L is the upper and L' the lower tube plate; M is the waste gas chamber or "smoke
box"; N is the funnel; O designates the heating tubes. It will be seen with
reference to the drawings that the tubes O are arranged in two nests, one on each
side of the gas producer A and the gas tube E, and that the combustion chamber C
and the waste gas chamber M are disposed, respectively, directly below and directly
above these tubes, their shape being made to correspond to the figure circumscribed
'by the outside row of tubes of the two nests thereof: this figure (i.e., the figure of the
combustion and waste gas chambers), it will be seen, is of crescent form.
The steam dome or chamber K is also arranged eccentrically to the centre of the
generator, but its centre is substantially coincident with the centre of the gas
producer A. The waste gas chamber M is provided with swinging smoke doors m¹
by which access is had thereto, and whereby means are provided for a ready access to
the tubes O for the purpose of cleaning them, or renewal, or other purposes.
A door e¹ and passage is provided at the bottom of the base of the generator, bv
which ready access is had to the combustion chamber C for the purpose of
inspection repairs, cleaning, and other object; and a door d³ is provided in this
wall d, separating the chamber D from the ashpit P, for gaining access to said
chamber D when desired.
It will be seen that the air used to convert the solid part in the furnace A to
a gaseous form, is delivered to the ashpit P by a steam jet blower Q, and that
the ashpit is enclosed with an ordinary close fitting door 6'; and the fuel is supplied
to the furnace A by an ordinary trapped shoot R, and is supported upon an ordinary
bar grate S.
With reference to the gas producing furnace A, the crown it will be seen, is semi-
spherical and the gas downtake tube E is attached to this crown at one side. By this
construction no staying is required. The producer A is arranged eccentrically for the
purposes chiefly of rendering the stoking and the clinkering and cleaning of the fires,
and the emptying of the ashpit easy. With a centrally arranged furnace all these
operations are far more difficult as they are too far from the outside of the generator;
and besides these ends, it is so designed for the purpose of so arranging the tubes in
the generator that the convection and circulation shall be efficient. And again the
respective arrangement of the shell, furnace, and tubes, is such, that the whole
operation of the generator shall be as good as possible, and the construction of the
parts simple, accessible, and strong.
Regarding the construction by which the tubes O are kept covered with water, it
will be seen that so long as the water level (which is designated W. L.) is maintained
at the point shewn in the figures, no portion of such tubes is not surrounded with
water; and, as is well known this is very advantageous to the life of the tubes,
especially during the process of getting up steam; however when steam is once "up"
damage to the tubes, if not so covered with water, is not so likely to occur,
especially when using fresh water; and then, if desired, the level of the water may
be let down below the upper tube, plate L. If this is done of course a greater free
- surface of water is obtained, and consequently a free liberation of steam would be
effected.
The converse of this arrangement consists in providing an annular steam dome
round the outside of the shell, at the same level as that shewn in the figures, the
smoke box being within it; or, both this, and the one shewn, may be provided.
The air used to support the combustion of the gases introduced into the combustion
chamber C is heated in passing through the horizontal passages I by coming in

page_text: contact with, and being subjected to the radiant heat of, the hot walls f; it passes
from these passages, into the chambers or conduits F, at 2, where the partition i¹ is
stopped. From here (wherein it receives additional heat) it passes into the com-
bustion chamber by the oblong apertures f¹, and is broken up into and delivered in a
number of comparatively thin streams, and meets corresponding streams of gas-
which also will be hot-issuing through corresponding apertures d¹ from the
chamber D. These divided streams of heated air and gas thereby assimilate, and
become thoroughly mixed, and complete combustion results.
It will be seen that the furnace A is practically wholly within the shell B
(ie., above the tube plate L') of the generator, and that the whole of its surface is
surrounded with water, so that no heat, due to radiation, is lost thereby, all of the
heat radiated from the walls of such furnace passing into the water surrounding it.
Also, it will be seen, the depth of the structure beneath the shell is small, and the
length of the tubes O for a given height of generator is great. Therefore by this
arrangement and construction a large extent of heating surface, in a generator of a
given height and size is afforded.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I would state in conclusion
that this invention is not confined to the particular construction and arrangement of
parts, as such parts may be modified in different ways to suit varying applications of
the invention, and requirements, without departing from its controlling features; also
one or more of the features of the invention may be applied to generators of
horizontal types, or generators differing in general form to the one particularly
described and illustrated. On the other hand I would have it understood that I am
aware of the Patents 4772 of 1882, 4088 of 1883, and 9433 of 1884 of H. C. Bull;
and also of the Patents 13733 of 1884 and 7633 of 1888 of G. H. Taylor, and that
I do not claim anything that is described and claimed in any of the aforesaid Patents,
but what I claim in respect of the herein described invention is :-
1. A "self-contained" gas-fired steam generator having a gas producing furnace
arranged eccentrically in, or relatively to, the shell thereof; substantially as and for
the purposes set forth.
2. A "self-contained" gas-fired steam generator having an eccentrically arranged
gas producing furnace; one or more downtake gas tubes (E); and nests of tubes O
arranged one on either side of such furnace; substantially as set forth.
3. A "self-contained" gas-fired steam generator having its gas producing furnace
arranged or disposed wholly within the shell of such generator, and surrounded with
water, substantially as and for the purposes set forth.
4. In a "self-contained" gas-fired steam generator, the combination of furnace A,
gas tube or tubes E, shell B, and tubes 0; substantially as set forth.
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5. In a self-contained gas-fired steam generator, the construction substantially
as described by which the heating tubes are adapted to be wholly surrounded or
covered with water.
6. The combination and arrangement of shell, steam dome or domes, and upper
tube plate, substantially as described for the purposes set forth.
7. In a "self-contained" gas-fired steam generator, effecting the distribution of air
and gas, and its introduction into the combustion chamber thereof; substantially as
described for the purposes set forth.
8. In a "self-contained" gas-fired steam generator, the form and arrangement of
combustion chamber C, substantially as set forth.
9. In a "self-contained" gas-fired steam generator, the horizontal arrangement of
passages for heating the air used to support the combustion of gases made in the gas
generator; substantially as set forth.
10. In a "self-contained" gas-fired steam generator, the combination and arrange-
ment of hot air chamber or conduit (F), gas chamber (D), and combustion chamber (C);
substantially as set forth.
11. In a self-contained" gas-fired steam generator, the combination and arrange-

page_text: ment substantially as described by which access is afforded to the gas chamber and
the combustion chamber; for the purposes specified.
12. A "self-contained" gas-fired steam generator having the gas producing
furnace A disposed therein eccentrically, ashpit P, gas chamber D, and combustion
chamber C, arranged substantially as described for the purposes specified.
13. A self-contained" gas-fired steam generator having the combustion chamber,
heated air and gas chamber or conduits, and ashpit, arranged at the lower part of the
structure, and the shell, lower tube plate, and gas producing furnace arranged or
disposed substantially wholly above and upon such lower parts; substantially as set
forth with reference to the drawings.
14. The herein described steam generator having its parts arranged and combined,
and adapted to operate, as set forth with reference to the drawings.
Dated this 14th day of June 1890.
CHEESBROUGH & ROYSTON,
15, Water Street, Liverpool, Applicant's Patent Agents.