Improvements in and in Connection with Furnaces for Steam Generators and for other purposes.
Year: 1889

page_text: Date of Application, 8th Jan., 1889
Complete Specification Left, 22nd July, 1889-Accepted, 24th Aug:,
1889
Improvements in and in Connection with Furnaces for Steam
Generators and for other purposes.
1 JACOB DAVIES of Llanfyllin near Oswestry, Shropshire, Brick Burner, do hereby
declare the nature of this Invention to be as follows:-
My Invention relates chiefly to the furnaces and connected parts of Steam
Generators, and has for its objects to promote the complete and economical combus-
tion of the carbonaceous constituents of the fuel and thereby to prevent the production
of smoke and to increase the proportionate useful effect. In one form of my inven-
Tion I employ a damper or regulating valve or shutter to regulate the area for the
passage of the heated products and admit air from above or at one side or at the
sides of such damper so that the air shall flow down or across the face of the damper
or through a hollow damper and meet the gases arising from the fuel and aid in their
complete combustion so as to prevent the formation of free carbon, or otherwise the
entering air is led to mingle with such gases just before they flow through, or as they
flow through or issue from the passage restricted by the damper or which may be
so restricted. By preference I arrange for the said damper to shut down upon the
top of the bridge or on the face or back of the bridge when closed. In the cases of
under-fired boilers I apply the damper in a suitable position at the back end of the
furnace or between the end of the furnace and the rear end of the boiler or at such
rear end.
In the cases of tubular or internal flued boilers I prefer to construct or
apply a furnace outside of the boiler and in pass the hot products of combustion
directly from such furnace into the flue or flues of the generator. In such a case
the damper would be between the furnace and the boiler or otherwise would be close
to the boiler end. Taking for example a Lancashire boiler having two flues 1 should
build or apply a furnace in front of the boiler end. This furnace would in some
cases be built in brickwork and in others would be of iron steel or metal and have
water spaces in the walls and crown. The furnace would be double that is to say it
would have two grates the two parts of the furnace being adapted to be fired alter
communication between one
nately. In some or in all cases we should have a
Furnace and the other so that one of the dampers could be closed and the evolved
In such a case I
gases be directed over the incandescent fuel in the other furnace.
should prefer to employ a boiler having a communication between the two flues at the
front end of the boiler or such communication may be established by means of a
In the cases wherein an outside furnace is
flue or passage in the furnace erection.
adopted the whole of the length of each internal boiler flue may be provided with
water tubes or pockets so that the proportional effective heating surface of the
generator would be increased as compared with an internally fired boiler.
furnaces situated as hereinbefore set forth in front of fluid boilers. I might modify the
arrangement as follows. The back of the furnace behind the bridge is formed with
inclined or it might be curved sides and top leading into a restricted passage having
parallel or inclined sides and opening into the boiler flue. I also provide an air
inlet or air inlets at or near the furnace bridge or at a suitable point in the aforesaid
inclined or curved sides or restricted passage. When the furnace is in operation the
heated gases or smoke from the furnace come into contact with the air entering at the
aforesaid air inlet as they rise over the bridge and become thoroughly oxygenized
and ignited.
The flame is drawn directly into the restricted passage or throat leading
to the flue and the unconsumed smoke and gases are directed by the aforesaid inclined
sides towards and into the said throat whereby they are forced into intimate combi-
mation with the flame and become ignited and are delivered in an ignited condition
TI

page_text: into the boiler flue. Thus not only is the smoke consumed but the whole length of
the boiler Hue is utilized as heating surface. The air admitted as aforesaid to assist
combustion is preferably heated by any suitable means..
Dated this 7th day of January 1889.
DUTTON & FULTON,
1. St. James Square. Manchester, Agents,
Improvements in and in Connection with Furnaces for Steam
Generators and for other purposes.
1 JACOB DAVIES of Llanfyllin near Oswestry, Shropshire. Brick Burner, do hereby
declare the nature of this Invention and in what manner the same is to be per-
formed to be particularly described and ascertained in and by the following statement
and accompanying drawings:-
My Invention relates chiefly to the furnaces and connected parts of Steam
Generators, and has for its objects to promote the complete and economical com-
bustion of the carbonaceous constituents of the fuel and thereby to prevent the pro-
duction of smoke and to increase the proportionate useful effect. In one form of my
invention employ a damper or regulating valve or shutter to regulate the area for
the passage of the heated products and I admit air from above or at one side or at the
sides of such damper so that the air shall flow down or across the face of the damper
or through a hollow damper and meet the gases arising from the fuel and aid in their
complete combustion so as to prevent the formation of free carbon, or otherwise the
entering air is led to mingle with such gases just before they flow through, or as
they flow through or issue from the passage restricted by the damper or which may
be so restricted. By preference I arrange for the said damper to shut down upon the
top of the bridge, or on the face or back of the bridge when closed. The invention
is applicable to under flued boilers or to boilers without flues. In the cases of
tubular or internally flued boilers I prefer to construct or apply a furnace outside of
the boiler and to pass the hot products of combustion directly from such furnace into
the flue or flues of the generator. In such a case the damper would be between the
furnace and the boiler or otherwise would be close to the boiler end. This furnace
would in some cases be built in brickwork and in others might be of iron, steel or
metal and have water spaces in the walls and crown. The furnace is applicable to the
single flued or to the Lancashire type of boiler and might be single
or double.
double it would have two grates the two parts of the furnace being adapted to be fired
alternately. In some or in all cases should have a communication between one
furnace and the other so that one of the dampers could be closed and the evolved
gases be directed over the incandescent fuel in the other furnace. The back of the
furnace behind the bridge is formed with inclined or it might be curved sides and top
leading into a restricted passage having parallel or inclined sides opening into the
boiler flue the said sides being either continuous or interrupted. The aforesaid air
inlet or air inlets are situated at or near the furnace bridge or at a suitable point in
the aforesaid inclined or curved sides or restricted passage and may be used either
with or without the aforesaid damper or dampers. When the furnace is in operation the
heated gases or smoke from the furnace come into contact with the air issuing from
the aforesaid air inlet or inlets as they rise over the bridge and become thoroughly
oxygenised and ignited. The flame is drawn directly into the restricted passage or
throat leading to or within the flue and the unconsumed smoke and gases are directed
by the aforesaid inclined sides towards and into the said throat whereby they are forced
into intimate combination with the same and become ignited and are delivered in an
ignited condition into the boiler flue. Thus not only is the smoke consumed but the
whole length of the boiler flue is utilised as heating surface. The air admitted as
aforesaid to assist combustion is preferably heated,
When

page_text: '
1
To render my invention more clear I will now proceed to describe the same more
particularly with reference to the annexed two sheets of drawings.
"
In sheet 1 of the drawings Fig. I is a vertical section of a steam generator to
which my invention is shown applied. Fig. 2 is a plan of the exterior of the same.
Fig. is a cross section of the steam generator at the line A. B. Fig. 1 and Fig. 4
is a cross sertion of the furnace at the line C. D. Fig. 1. In the said drawings E is
the furnace which as has been said is placed in front of the boiler and F is a single
flued steam boiler of the ordinary construction. The furnace as shown is constructed
of brickwork and consists of a rectangular erection the centre of the furnace being
opposite to the centre of the flue a. The furnace grate is composed of bars as usual
the outer ends of the front bars resting on the dead plate and the inner ends of the
back bars resting on a support d. Behind the support is a space e into which the
clinkers may be pushed from the bars 6 and thereafter drawn to the front of the
furnace through the space closed by the door 2. Behind the space is the bridge f.
and above the bridge is an air port g through which heated air is discharged upon
the smoke and heated products of combustion as they pass over the bridge from the
furnace as indicated by the arrows. The entrance behind the bridge into the flue is
restricted as shown by the sloping sides of the throat of the furnace so as to bring
together and condense the products of combustion and bring them into more intimate
contact with the heated air. To render this restriction of the throat variable at will
I apply an adjustable damper which is carried over pullies by a
suspending
chain and is counterbalanced by a weight in front of the furnace. By moving this
weight up or down the damper can be raised or lowered and the throat of the furnace
contracted or enlarged at pleasure. The damper is placed immediately behind the
air porty and when the damper is in use the heated air streams over the face of the
damper and comes in contact with the smoke and heated products of combustion.
The damper might however be dispensed with and a damper might be placed at the
rear of the boiler or in any other suitable position or the damper / might be used in
combination with another damper situated at the rear. The air issuing from the
port is heated by being caused to circulate through zig-zag passages 7 formed in
the curved crown of the furnace. The zig-zag passages are clearly shown in dotted
lines in Fig. 2. in longitudinal section in Fig. I and in cross section in Fig. 4. The
air enters at the front of the furnace and after traversing the passages 7 as shown by
the arrows is discharged into the throat of the furnace through the air port g as already.
described. The flue of the boiler contains means for utilising the evolved heat.
These means consist of a number of objects composed either of fire clay or of metal
or of combinations of fire clay and metal and arranged so as to catch and retain as
much of the heat as possible without unduly restricting the draught. The said objects
consist of a series of rings . . . p. q spaced a certain distance apart and successively
diminishing in diameter as they extend into the flue the series terminating in a
partition of fire brick or of metal formed with a number of perforations to admit of
the passage of the flame and hot gases. The rings form together what I have herein-
before referred to as a restricted or tapering passage for the heat and are supported
from the interior of the flue upon supports or feet of fire-clay or of metal. When
the furnace is in operation the smoke and heated products of combustion in passing
over the bridge are met by the current of heated air issuing from the air port y and
being thus oxygenised under favourable conditions, burst into flame and rush through
the restricted throat of the furnace into the flue. The restricted throat or the lowered
damper tends to force together the current of flame and gases and further assists
combustion so that within the flue the combustion is almost or nearly perfect. As the
flame pours through the flue a it impinges upon the successive rings or objects and
heats them to such a degree that any unconsumed carbon which may exist is ignited
by contact with the rings. The perforated partition spreads and equalises the fame
and heat which may thereafter be led back along the sides of the boiler or directly
to the outlet or chimney as thought fit. The brick-work or metallic rings and
partition becoming highly heated impart heat to the boiler and thus perform a double
duty. The furnace being outside of the boiler and the heat evolved before the
"

page_text: A
products of combustion are admitted to the flue it will be evident that the whole of the
heating surface of the flue is utilised, whereas under ordinary conditions where the
fue contains the furnace the portion of the flue in the front portion of the furnace
grate and also the portion beneath the grate is practically useless as heating surface.
According to my invention every inch of the flue is utilised as beating surface.
port closed by a door y is provided in the front of the furnace so that a view of the
interior of the furnace and flue can be obtained from without. I do not limit myself
to the exact shape of the furnace nor to the number or proportion of the rings.
partitions or the like as these do not affect the spirit and principle of
my invention.
For example the furnace instead of being constructed of brickwork might be made
of metal and formed with water spaces which water spaces might be utilised to heat
the feed water previous to its being injected or pumped into the boiler or the water
Instead of having
Spares might be placed in communication with the economiser.
the furnace made as a fixture in front of the builer it might he constructed as a
separate body and mounted on a carriage or bogie capable of being traversed on
rails or plates in front of the boiler or in front of a range of boilers. By making
the furnace moveable in this manner increased facilities are gained for cleaning the
hoiler and flues. Furthermore the furnace instead of being constructed in front of
the boiler might be ranged alongside of it the heat being conducted to the boiler
by a flue.
Sheet 2 of the annexed drawings illustrates modifications of my invention to which
I have referred in the provisional portion of my specification. Fig. 5 is a longitudinal
vertical section and Fig. 6 is a plan partly in section. The drawings illustrate their
application to a double flued boiler and accordingly the furnace is shown with a
double grate-although apart from these features the construction of furnace is
almost the same as that described with reference to sheet 1. The two boiler flues a.
lie about opposite to the two grates 6. and in each instance I may use the adjustable
damper as already described. It will be seen that in Fig. 1 the arrangement and
form of the heat intercepting objects in the flue differ from those described with
reference to sheet 1. Immediately behind the ring which terminates the restricted
throat of the furnace I place a perforated partition : behind the partition I place a
solid disc w and lastly an annular ring. In operation the restricted throat and
ring concentrate the flame, the perforated partition spreads and equalises the same
the solid disc brings the whole of the flame into intimate contact with the interior of
the flue and again the ring e tends to split it up. I might have a greater number
of rings, partitions and dises than the number shown. In the double furnace I might
fire each grate alternately and arrange to pass the smoke and gases of one grate say
for example through the opening as shown by the arrows in Fig. 6 and cause
them to pass over the incandescent fuel on the grate and thus become inflamed
and ignited. In such a case the grate 6 would of course be cut off from its
corresponding flue a by means of the damper . Under ordinary working conditions
the opening would be closed by a damper indicated by the dotted line in Fig. 6.
The boiler flues may be provided with water tubes or pockets either of the ordinary
or of a suitable description. It will of course be evident that my improved outside
furnace might be applied to steam generators unprovided with flues and that it might
be applied to heating purposes other than the heating of steam generators.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
(1) The general arrangement and combination of furnace and heating means for
The purposes and substantially as described and shown.
.
(2) As a means for heating steam generators or for other heating purposes a
furnace placed outside of the generator and formed with air heating passages and
with or without an adjustable damper substantially as described and shown.
(3) As a means for heating steam generators a furnace or furnaces placed in front
of or outside of the generator and having air heating passages and a damper or

page_text: dampers in combination with rings, dises, partitions or similar heat intercepting and
transmitting objects placed in the fine or in the flues of the generator substantially as
described and shown.
(4) In a furnace for heating steam generators or for other heating purposes (placed
in front of or outside of the generator and having a double grate with dampers and
air heating passages) connecting the two grates by a port or ports in the dividing
wall capable of being shut and opened so that the smoke and products of combustion
from one grate can at will be directed into the other grate and burned therein
substantially as described and shown with reference to sheet 2 of the drawings.
Dated this 20th day of July 1889.
DUTTON & FULTON.
1, St. James Square, Manchester, Agenis.