IMPROVEMENTS IN EFFECTING THE COMBUSTION OF FUEL IN LOCOMOTIVE BOILER AND OTHER FURNACES, AND IN APPARATUS CONNECTED THEREWITH
Year: 1876

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN
EFFECTING THE COMBUSTION OF FUEL IN LOCOMOTIVE BOILER AND OTHER
FURNACES, AND IN APPARATUS CONNECTED THEREWITH." A communication
from abroad by John Eastburn Wootten, of Reading, County of Berks, State of
Pennsylvania, United States of America.
Sealed the 5th December 1876, and dated the 13th June 1876.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 13th June 1876.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN EFFECTING THE COMBUSTION OF FUEL IN Loco-
MOTIVE BOILER AND OTHER FURNACES, AND IN APPARATUS CONNECTED THEREWITH."
A communication from abroad by John Eastburn Wootten, of Reading, County of
Berks, State of Pennsylvania, United States of America.
This Invention relates more particularly to various improvements in the methods
or means of effecting the combustion of fuel in locomotive boiler and other furnaces,
as herein-after described.
The main object of the first part of the Invention is to utilize as an available
fuel for generating steam in steam boilers and for other purposes waste or refuse
coal, and especially anthracite coal, the Invention being also applicable to the
burning of inferior coal generally.
In carrying out this part of the Invention as applied to the fire-box of the boiler
of a locomotive type the fire-box is fitted with the usual system of tubes opening
thereinto, and with a fire door and fuel bed. The latter, however, in lieu of being
constructed in the ordinary manner is composed of perforated and flanged plates or
channel bars of wrought iron, the flanges of one bar being secured to those of the
adjoining bar, and the whole forming a continuous perforated bed strengthened by
the flanges and resting on ledges or projections in the interior of the fire-box.
Beneath the fuel bed and to the lower edge of the fire-box is secured an ash-
pan closed at the bottom and on all four sides, excepting where air is introduced
undor pressure, the doorway through which ashes are removed being closed while
the furnace is in operation.
Finely granulated refuse coal placed in a comparatively thin layer on the per-
forated fuel bed, and subjected to the action of numerous small jets of air under

page_text: pressure becomes incrusted or coked, hence the fuel must be stirred or broken up
from above from time to time so that there may be free access to and through the
fuel of the jets of air. By this treatment the waste coal and anthracite will burn
with an intense heat, and will be thoroughly consumed, nothing remaining but ashes
so fine that in boilers of the locomotive type they will be carried through the tubes
to the smoke box.
The fuel will burn with an intensity proportionate to the volume of air admitted
to the closed ash-pan, and therefore the volume of air should be proportionate to
the requirements of the boiler. The pressure of steam in the boiler is caused to
automatically regulate the admission of air into the ash-pan through the medium
of a device next herein-after described.
A tube is employed closed at one end by a screw cap, and terminating at the
other end in a nozzle, to which is adapted a valve, the latter having a notched
disc which serves as a guide for the valve, but permits the free passage of steam
to and through the nozzle. The stem of the valve is connected by a spiral spring
to an adjusting screw which passes through the screw cap. The tube is provided
with a branch communicating through a small pipe with the steam space of the boiler.
The tube is connected by arms to the mouth of a pipe, which is secured to the ash-
pan and projects within the same, and is furnished at its inner end with a valve.
It is preferred to make this pipe flaring in the two directions, so that there shall
be a free admission of air at the mouth, and so that the air shall be diffused on
being discharged into the ash pan.
The spring must be adjusted in accordance with the desired pressure of steam in
the boiler; if, for instance, it is desirable to maintain a pressure of 50 lbs. per square
inch the spring should be such that it will yield to the pressure of steam on the
valve, and the latter will be closed to its scat when this pressure is reached; the
valve however will be opened by the spring to an extent depending upon the
decrease in the pressure of steam below 50 lbs. per square inch. The quantity and
pressure of air admitted to the mouth of the pipe, and consequently to the ash pan,
will depend upon the volume of steam which escapes into the mouth from the
nozzle, and as the force of the steam jot depends on the pressure of steam in the
boiler, the latter must regulate the supply of air to the ash pan and must control
the burning fuel in accordance with its own requirements.
The number of pipes and nozzles may be increased in accordance with the dimen-
sions of the fire-box.
There should be provided in connection with each nozzle or with the steam pipe
communicating therewith a suitable cock, by manipulating which the engineer may
cut off the steam, and the valve of each air pipe should be so hung or so weighted
that it will be self-closing when the operation of the steam jet ceases, thereby
excluding the air from the ash pin. The importance of this self-closing valve
however becomes most prominent where several air pipes and steam nozzles are
used, for should the access of steam to one or more nozzles be cut off the valves of
the air pipes appertaining to these nozzles will be closed, thereby preventing the
return of the air introduced through the medium of steam jets by the other nozzles
through their air pipes into the closed ash pan.
A fire-bed, presenting a number of perforations, may be constructed in different
ways, but it is preferred to make it of comparatively thin plate iron in sections or
bars flanged at the edges, these flanges being made either by bending the edges of
the plates or during the rolling of the same, and serving the twofold purpose of
preventing the fuel bed from warping, and of affording the means of securing the
plates together.
The second part of this Invention has for its object the remedying of defects in
those features of a locomotive engine which relate to the combustion of fuel and the
disposal of the sparks. These defects are the constant disturbance and tearing up
of the fuel caused by the intermittent blasts of exhaust steam, and resulting not
only in the waste of fuel, but in injury to the tube sheets, and abrasion and rapid
destruction of the tubes.

page_text: Heretofore the exhaust steam of locomotive engines has been usually utilized by
causing it to create a draft for supporting combustion, and for clearing the tubes
and disposing of the sparks, and to a limited extent for heating the feed water, but
the advantages thus gained have always been accompanied with the evils above
referred to.
It has been discovered and determined by practical tests that a much more
uniform and economical burning of the fuel can be accomplished without the aid of
the exhaust steam, and by the simple use of an induced and continuous blast of
air beneath the fire-grate, combined with a steady jet or jets of live steam in the
chimney, which cause a draft of sufficient intensity to induce the entire products
of combustion to pass through the flues, even should the furnace doors be open.
The result of this combination is the uniform, economical, and quiescent combustion
of the fuel, and the prevention of violently emitted sparks, which have such a
detrimental effect on the tubes of ordinary locomotive boilers.
In carrying out this part of the Invention the ash-pan is closed, as herein-before
described, excepting at the inducting pipe, through which air is caused to pass by a jet
from a steam nozzle communicating through a pipe with one of the steam pipes of
the engine at a point between the usual throttle valve and the steam chest, so that
when the said throttle valve is closed the escape of steam at the nozzle and conse-
quently the introduction of air under pressure to the ash-pan ceases. Two, three,
or more of these pipes and nozzles may be used. Each induction pipe is furnished
with a self-closing valve, and also with regulating devices.
It is proposed to apply in the smoke box of the boiler a feed water heater,
through which the exhaust steam passes, and which may be similar to those in
common use.
The exhaust steam, instead of being discharged into the chimney as usual passes
through a pipe into a stand pipe, which is by preference furnished at the top with a
suitable valve under the control of the engineer. The pipe is bent downward
within the stand pipe, or is otherwise so arranged as to prevent the direct upward
escape of the steam.. The water of condensation is thus projected downward, while
the vapor escapes through the top of the pipe when its valve is open. This water
of condensation passes through a pipe into the tender, and by closing the valve the
vapor which would otherwise escape into the atmosphere will also be forced through
the pipe last mentioned into the tank of the tender.
The pipe for injecting live steam into the chimney may be fitted with a nozzle or
similar device, and be connected to one of the steam pipes, the connection being by
preference at a point between the throttle valve of the engine and the steam chest,
so that on closing the said throttle valve the discharge of the live steam into the
chimney will cease.
An additional feed water heater may be placed on the boiler, and through this
heater the steain and water can circulate after passing from the stand pipe and
before it reaches the tank of the tender. It is preferrable that the heater or heaters
should be interposed between the force pump of the engine and check valve of the
boiler. Even if the exhaust steam be discharged into the atmosphere in such a
manner that it cannot influence the draft, for instance, if it is caused to pass
directly through and above the chimney, the introduction of air under pressure into
the closed ash-pan in connection with the draft induced by the continuous jet of
live steam into the chimney in place of the intermittent blasts, exhaust steam
will result in the economizing of fuel for the products of combustion, instead of
rushing through the tubes with intermittent impulses, as usual, will take such a
steady and comparatively slow course through the said tubes that their heat will
be effectually absorbed.
A further economy of fuel is however insured in utilizing the exhaust steam thus
relieved from its usual function of promoting the draft by using it as a medium for
heating the feed water, and causing it by condensation to contribute to the supply
of heated feed water.
The third part of this Invention relates to the maintenance of a continuous

page_text: draught in the chimney of a boiler by the use of jets of live steam, the object being
to obtain intensity of action by a small amount of steam.
In carrying out this part of the Invention it is proposed to place in the chimney
a number of vertical induction pipes, say, for example, seven, the spaces intervening
between the exteriors of these pipes being closed, so that the products of combustion
shall pass through the pipes only on their way to the exterior atmosphere.
Into each passage is injected a jet of live steam derived by preference from a
coiled tube communicating with the steam space of the boiler, the coil having as
many perforations or nozzles as there are pipes, and so situate in respect to the
latter that a jet of steam will be projected upwards into the centre of each pipe.
The steam pipe may be furnished with a suitable valve placed under the control
of the engineer.
It has been ascertained that by this arrangement of induction pipes greater
intensity of action can be attained with a given quantity of steam than by dis-
charging the jets directly into the chimney. The arrangement of induction pipes
and jets moreover permits a more readily adjustable intensity of draught requisite
for the varying volume of flame produced during the combustion of waste coal
dirt, for aiding in the combustion of which the device is more especially intended.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Henry Johnson in the Great Seal Patent Office on the 7th
December 1876.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. " IMPROVEMENTS IN EFFECTING THE COMBUSTION OF FUEL IN Loco-
MOTIVE BOILER AND OTHER FURNACES, AND IN APPARATUS CONNECTED THEREWITH."
A communication from abroad by John Eastburn Wootten, of Reading, County of
Berks, State of Pennsylvania, United States of America.
The said Invention relates more particularly to various improvements in the
methods or means of effecting the combustion of fuel in locomotive boiler and
other furnaces, as herein-after described, reference being had to the Sheet of
Drawings hereunto annexed.
One part of the Invention has for its main object utilizing as an available fuel
for generating steam in steam boilers and for other purposes waste or refuse coal,
and especially anthracite coal, the Invention being also applicable to the burning of
inferior coal generally.
Figure 1 of the accompanying Drawings is a vertical section of the fire-box end
of a boiler of the locomotive type illustrating the mode of carrying this part of the
Invention into effect.
Figure 2 is a transverse section of part of the fire-box and of the perforated fuel
bed which forms a feature of this Invention.
Figure 3 is a perspective view of the fuel bed drawn to an enlarged scale; and
Figure 4 is an enlarged sectional view of a device by which the supply of air for
supporting combustion is automatically regulated in accordance with the demands
of the boiler.
A is the fire-box of the boiler; B, the usual system of tubes; D, the fuel door;
and E, the fuel bed, which is in the present instance composed of perforated and
flanged plates or channel bars d of wrought iron, the flanges of one bar being
secured to those of the adjoining bar, and the whole forming a continuous perforated
bed, strengthened by the flanges and resting on ledges or projections in the interior
of the fire-box.
Beneath the fuel bed E and to the lower edge of the fire-box is secured an
pan F, closed at the bottom and on all four sides, excepting where air is introduced

page_text: under pressure, as herein-after described, the doorway through which ashes are
removed being closed while the furnace is in operation.
Finely granulated refuse coal placed in a comparatively thin layer on the per-
forated fuel bed and subjected to the action of numerous small jets of air under
pressure becomes incrusted or coked, hence the fuel must be stirred or broken up
from above from time to time so that there may be free access to and through the
fuel of the jets of air. By this treatment the waste coal and anthracite will burn
with an intense heat and will be thoroughly consumed, nothing remaining but
ashes, so fine that in boilers of the locomotive type they will be carried through the
tubes to the smoke box.
The fuel will burn with an intensity proportionate to the volume of air admitted
to the closed ash-pan, and therefore the volume of air should be proportionate to
the requirements of the boiler. Through the medium of the device illustrated by
the enlarged view, Figure 4, the pressure of steam in the boiler is caused to auto-
matically regulate the admission of air into the ash-pan in the manner next herein-
after described.
A tube G is employed, closed at one end by a screw cap a and terminating at
the other end in a nozzle b, to which is adapted a valve c, the latter having a
notched disc e which serves as a guide for the valve but permits the free passage of
steam to and through the nozzle b. The stem of the valve is connected by a spiral
spring to the adjusting screw h which passes through the screw cap a.
The
branch of the tube G communicates through a small pipe with the steam space of
the boiler. The tube G is connected by arms m to the mouth n of a pipe M which
is secured to the ash-pan and projects within the same, and is furnished at its inner
end with a valve p. It is preferred to make this pipe M flaring in the two directions,
as shown in Figure 1, so that there shall be a free admission of air at the mouth,
and so that the air shall be diffused on being discharged into the ash-pan.
The spring should be adjusted in accordance with the desired pressure of steam
in the boiler; if, for example, it is desirable to maintain a pressure of 50 lbs. per
square inch the spring should be such that it will yield to the pressure of steam on
the valve c, and the latter will be closed to its seat when this pressure is reached,
the valve however will be opened by the spring to an extent depending upon the
decrease in the pressure of steam below fifty lbs. per square inch. The quantity and
pressure of air admitted to the mouth of the pipe M, and consequently to the ash-
pan, will depend upon the volume of steam which escapes into the mouth from the
nozzle b, and as the force of the steam jet depends on the pressure of steam in the
boiler it follows that the latter will regulate the supply of air to the ash-pan and
will control the burning fuel in accordance with its own requirements.
It should be understood that although but one air pipe M and one steam nozzle
have been shown in connection with the ash pan, the number of pipes and nozzles
may be increased in accordance with the dimensions of the fire-box.
There should be provided in connection with each nozzle, or with the steam pipe
communicating therewith, a suitable cock, by manipulating which the engineer may
cut off the steam, and the valve p of each air pipe should be so hung or so weighted
that it will be self-closing when the operation of the steam jet ceases, thereby
excluding the air from the ash pan. The importance of this self-closing valve how-
ever becomes most prominent where several air pipes and steam nozzles are used,
for should the access of steam to one or more nozzles be cut off the valves of the
air pipes appertaining to these nozzles will be closed, thereby preventing the return
of the air introduced through the medium of steam jets by the other nozzles
through their air pipes into the closed ash pan.
A fire-bed presenting a number of perforations may be constructed in different
ways, but it is preferred to make it of comparatively thin plate iron in sections or
bars flanged at the edges, these flanges being made either by bending the edges of
the plates or during the rolling of the same, and serving the two-fold purpose of
preventing the fuel bed from warping and of affording the means of securing the
plates together. In practice plate iron of about a quarter of an inch thick, with

page_text: perforations about three-eighths of an inch in diameter, arranged substantially as
shown in Figure 3, has been used, and this use of plate iron is preferred, for it may
be so thin that the perforations cannot be choked by the ashes.
The Invention has for its object, secondly, the remedying of defects in those
features of a locomotive engine which relate to the combustion of fuel and the
disposal of the sparks. These defects are the constant disturbance and tearing up
of the fuel caused by the intermittent blasts of exhaust steam, and resulting not
only in the waste of fuel but in injury to the tube sheets, and abrasion and rapid
destruction of the tubes.
Heretofore the exhaust steam of locomotive engines has been ordinarily utilized
by causing it to create a draft for supporting combustion and for clearing the tubes
and disposing of the sparks, and to a limited extent for heating the feed water, but
the advantages thus gained have always been accompanied with the evils above
referred to..
Now it has been discovered and determined by practical tests that a much more
uniform and economical burning of the fuel can be accomplished without the aid of
the exhaust steam, and by the simple use of an induced and continuous blast of air
beneath the fire grate, combined with a steady jet or jets of live steam in the
chimney, which cause a draft of sufficient intensity to induce the entire products of
combustion to pass through the flues, even should the furnace doors be open. S
The result of this combination is the uniform, economical, and quiescent combustion
of the fuel, and the prevention of violently emitted sparks, which have such a
detrimental effect on the tubes of ordinary locomotive boilers.
Figure 5 of the accompanying Drawings is a side view partly in section of
sufficient of a locomotive boiler to illustrate this part of the Invention, and Figure 6 1
a view of the smoke box end of the boiler. A is the fire-box of the boiler; B the
nsh pan, which should be closed, excepting at the inducting pipe C, through which
air is caused to pass by a jet from a steam nozzle a communicating through a pipe E
with one of the steam pipes N of the engine, at a point between the usual throttle
valve and the steam chest, so that when the said throttle valve is closed the escape
of steam at the nozzle a, and consequently the introduction of air under pressure
to the ash pan ceases.
It should be here understood that although I have alluded and shall hereafter
allude to but one induction pipe C and one steam nozzle a, two, three, or more pipes
and nozzles may be used. It should be also understood that each induction pipe is
furnished with a self-closing valve and also with regulating devices.
In the present example I have shown in the smoke box D of the boiler a feed-
water heater H, through which the exhaust steam passes, and which may be similar
to those in common use, but although it is preferred to use this heater it is not
essential to the Invention.
The exhaust steam, in lieu of being discharged into the chinney I as usual,
passes through a pipe J into a stand pipe K, which is by preference furnished at
the top with a suitable valve w under the control of the engineer. The pipe J is
bent downwards within the pipe K, or is otherwise so arranged as to prevent the
direct upward escape of the steam. The water of condensation is thus projected 4
downward while the vapor escapes through the top of the pipe when its valve is
open; this water of condensation passes through a pipe M into the tender, and by
closing the valve w the vapor, which would otherwise escape into the atmosphere,
will also be forced through the pipe M into the tank of the tender. The length of
time during which the valve may remain closed will depend upon the condition of 5
the water in the tender, as regards temperature.
The pipe m for injecting live steam into the chimney may be connected to one of
the steam pipes N, N, as shown in Figure 6, the connection being by preference at
a point between the throttle valve of the engine and the steam chest, so that on
closing the said throttle valve the discharge of the live steam into the chimney will 5
cease.
·As. before remarked, it is preferred to use a feed water heater in the smoke box,

page_text: as the greatest heat will be there imparted to it. An additional heater may how-
ever be placed on the boiler, as indicated by dotted lines at H, and through this
heater the steam and water can circulate after passing from the waste pipe K and
before it reaches the tank of the tender. It is preferable that the heater or heaters
should be interposed between the force pump of the engine and check valve of the
boiler.
It may be observed that even if the exhaust steam be discharged into the atmo-
sphere in such a manner that it cannot influence the draft, for instance, if it is
caused to pass directly through and above the chimney, as shown by dotted lines
at a¹ in Figure 5, the introduction of air under pressure into the closed ash pan in
connection with the draft induced by the continuous jet of live steam into the
chimney in place of the intermittent blasts of exhaust steam will result in the
economizing of fuel for the products of combustion, instead of rushing through
the tubes with intermittent impulses as usual, will take such a steady and com-
paratively slow course through the said tubes that their heat will be effectually
absorbed.
A further economy of fuel is however insured in utilizing the exhaust steam thus
relieved from its usual function of promoting the draft by using it as a medium for
heating the feed water, and causing it by condensation to contribute to the supply
of heated feed water.
The Invention has reference, thirdly, to the maintenance of a continuous draught
in the chimney of a boiler by the use of jets of live steam, the object being to obtain
intensity of action by a small amount of steam.
Figure 7 of the accompanying Drawings is a side view partly in section of the
smoke box end of a boiler with the improvements which form the subject of this
part of the Invention applied thereto; Figure 8 is a sectional plan taken along the
line 1-2 (Figure 7); and Figure 9 is a detached view of part of the device.
A is the smoke box of the boiler, and B the chimney, within which are placed
a number of vertical induction pipes 6 (seven being represented as employed in the
present example), the spaces intervening between the exteriors of these pipes being
closed, so that the products of combustion shall pass through the pipes only on their
way to the exterior atmosphere.
Into each passage b is injected a jet of live steam, derived by preference from a
coiled tube D, Figure 9, communicating with the steam space of the boiler, the coil
having as many perforations or nozzles as there are pipes b, which perforations or
nozzles are so situate in respect to the latter that a jet of steam will be projected
upwards into the centre of each pipe.
The steam pipe may be furnished with a suitable valve placed under the control
of the engineer.
It has been ascertained by practical tests that by this arrangement of induction
pipes greater intensity of action can be attained with a given quantity of steam
than by discharging the jets directly into the chimney. The arrangement of
induction pipes and jets moreover permits a more readily adjustable intensity of
draught requisite for the varying volume of flame produced during the combustion
of waste coal dirt, for aiding in the combustion of which the device is more
especially intended.
*Having now described and particularly ascertained the nature of the said Inven-
tion, and the manner in which the same is or may be used or carried into effect,
I would observe in conclusion that I do not claim broadly, either separately or in
combination, the introduction of air under pressure into a closed ash pan, or the
introduction of a jet of live steam into the chimney, but what I consider to be novel
and original, and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent is,-
First. The mode herein described of burning waste coal in steam boiler and other
furnaces, that is to say, by repeatedly stirring or breaking up the ignited fuel from
above, while it is subjected from below to numerous jets of air under pressure, as set
forth.

page_text: Second. The combination in a steam boiler furnace of a perforated fuel bed E
a closed ash pan F, and a pipe or pipes through which an under pressure can be
introduced into the said pan below the perforated bed, all substantially as herein-
before described and illustrated by Figures 1, 2, 3, and 4 of the accompanying
Drawings.
Third. The within described fire-bed, composed of perforated flanged plates or
channel bars of wrought iron connected together, as set forth.
Fourth. The combination of a pipe M for the admission of air for supporting com-
bustion in a steam boiler furnace with a steam nozzle b adapted to a valve c, which
is controlled partly by the pressure of steam in the boiler and partly by a spring, all
substantially as herein-before described and illustrated by Figures 1 and 4 of the
accompanying Drawings.
Fifth. The combination of the tube G, its branch i, and nozzle b with the valve c,
spring f, and adjusting screw h, all substantially as herein-before described and
illustrated by Figures 1 and 4 of the accompanying Drawings.
Sixth. The mode herein described of burning fuel in and preventing the emission
of sparks from locomotive boilers, that is to say, by forcing by means of a jet or jets
of live steam a continuous blast of atmospheric air into a closed ash pan, and by
introducing into the chimney a continuous jet or jets of live steam sufficient in force
or volume to prevent the escape of the products of combustion through the door of
the furnace when open, but insufficient to cause the emission of sparks from the
chimney, all as set forth.
Seventh. The combination of the closed ash pan and air pipe C with a nozzle a
cominunicating with a steam pipe of- the engine at a point between the steam chest
and throttle valve, so that the introduction of air under pressure into the ash pan
shall cease simultaneously with the cutting off of steam from the engine, as
specified.
Eighth. The combination of the chimney with a pipe communicating at one end
with a main steam pipe of the engine at a point between the throttle valve and
steam chest, and terminating at the upper end in a nozzle, nozzles, or other devices
for discharging a jet or jets of live steam into the said chimney when the throttle
valve is open.
Ninth. The combination with a steam boiler chimney of a series of induction
pipes and a device by which a jet of steam is injected into each pipe, all substan-
tially as herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this my Speci-
fication set my hand and seal, the Thirteenth day of November, One
thousand eight hundred and seventy-six.
J. HENRY JOHNSON. (LS.)