IMPROVEMENTS IN FURNACES
Year: 1884

page_text: We RICHARD MORRIS of Doncaster in the County of York and JAMES WOOD of
West Stockworth in the County of Nottingham engineers do hereby declare the
nature of our said Invention for IMPROVEMENTS IN FURNACES" to be as
follows:-
This Invention relates to furnaces for steam boilers or for metallurgical or other
purposes and has for its object to attain a more perfect combustion of fuel of any
quality thau is attainable in furnaces as hitherto constructed.
According to the said Invention the fire bars are made of but small thickness or
width and of a taper form in cross section narrower at bottom than at top so that
when the bars are placed together there are obtained between the bars air spaces
which are wider at bottom than at top. In the upper part of the bars transverse
passages or openings are formed extending some little distance into the body of the
bar and being preferably taper so as to be wider at bottom than at top and with
an inclined lower portion for the purpose of allowing ash to drop clear from them
and also to facilitate the air supply. The bars are set apart to such a distance
that the total area of the spaces between the portions of the bars upon which the
fuel rests is as great as is possible consistently with the necessary strength of the
bars It is considered that the best effect for locomotive boilers or the like will
be obtained by using bars of a width of about a quarter of an inch at top tapering
to one eighth of an inch at the lowest part and with transverse openings one
quarter of an inch in width at top and three quarters of an inch apart the said
bars being set a quarter of an inch apart-this giving a total area of air space of
about 70 per cent of the total grate surface-For ordinary metallurgical furnaces
or other furnaces subject to great strain bars may be used of a width of as much
as half an inch tapering down to a quarter of an inch and being set about five
sixteenths of an inch apart. For furnaces of Cornish Lancashire or Marine Boilers
generally and for furnaces of a like kind the two descriptions of bars hereinbefore
named may be combined the wider bars being situated next the bridge—The fire
door end of the furnace above the fire bars is preferably without air openings so as
to prevent cold air from gaining admittance to the furnace from above the fuel.
The air for the combustion of the fuel on the bar is supplied from the Ash pit the
said air passing to the fuel by the before named spaces between and in the bars.
The bridge is preferably contracted or formed with an opening or openings, the
sides and top of which form a superheating surface for the products of combustion

page_text: passing through the said opening or openings for in Cornish or Lancashire or like
Boilers there should be an opening on each side of the bridge in order to burn the
gases which bave passed through the bridge an air passage or passages is or are
made in the lower part of the bridge provided with a pipe or its equivalent opening
behind the bridge at the part or parts where the unconsumed combustible gases
pass on their way to the chimney-By this means the Oxygen from the air is
brought into direct contact with the superheated gases which have not been
previously injuriously diluted by air admitted above the fire bars and by this
means the said gases are practically entirely burned and the whole of the caloric
is thus utilized. The air opening to the passage or passages to the back of the
bridge may be provided with a damper which can be operated from the exterior
so as to regulate or cut off the supply of air as desired. In order to prevent the
formation of smoke whilst charging furnaces with fuel owing to the inlet of air
by the furnace door it is preferred to provide a damper in the flue for each furnace
the said damper being so connected to the furnace door by an arrangement of levers
and rods or the like that on the door being opened the damper will be automatically
closed or partially closed to be again automatically opened when the furnace door
is closed.
J. HENRY JOHNSON,
47, Lincoln's Inn Fields, London, W.C.,
Agent for the said Richard Morris
and James Wood.

page_text: We RICHARD MORRIS of Doncaster in the County of York and JAMES WOOD of
West Stockwith in the County of Nottingham Engineers do hereby declare the
nature of said invention for IMPROVEMENTS IN FURNACES 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 Furnaces for steam boilers or for Metallurgical or other
purposes and has for its principal object to attain a more perfect combustion of
fuel, of any quality, than is attainable in furnaces as hitherto constructed. By
constructing the bars of the furnaces as hereinafter described they will last much
longer than will ordinary bars.
In furnaces constructed according to the said Invention the fire bars are made of
a taper form in cross section and have transverse air spaces in the upper part so
shaped (as hereinafter described) as to give a clear drop for the Ash, and maintain
a passage for Air therethrough. The fire door end of the furnace is preferably
without air openings so as to prevent cold air from gaining adinission to the
furnace from above the fuel. The air for the combustion of the fuel or the bars, is
supplied from the Ash pit the said Air passing to the fuel by the spaces between
the bars and by the before named transverse air spaces in the upper part of the
bars.
The bridge above the fire bars is preferably constructed or formed by a partition
having an opening or openings therein the side and upper parts of which form a
superheating surface for the products of combustion passing through the said
opening or openings and deliver the gases in a compact body through the bridge
In order to burn the superheated combustible gases which have passed through or
over the bridge an air passage or passages is or are made in the lower part of the
bridge below the fire bars and the air passage (or each air passage where more than
one is employed) is provided with a pipe or passage opening behind the bridge at
the part (or parts) where the unconsumed combustible gases pass on their way to
the chimney so as to deliver air in the direction of the draught and in the midst of
the gases which have passed over or through the bridge. The air passage or
passages is or are provided with a valve or valves or damper or dampers by means
of which the quantity of air admitted behind the bridge can be regulated or cut of
as desired.
And in Order that the said Invention may be fully understood we shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 represents in side elevation and Figure 2 in transverse section a fire
bar for use in a furnace constructed according to this Invention Figure 3 is a
longitudinal section of a furnace provided with the said fire bars and otherwise
arranged according to this Invention as hereinafter described Figure 4 is a
transverse section on the line 1, 2 figure 3. The fire bars are made of a taper
form in cross section narrower at bottom than at top so that when the bars are
placed together there are obtained between the bars air spaces which are wider at
bottom, than at top. In the upper part of the bars transverse passages or openings a
are formed extending some little distance into the body of the bar and being taper
the wider part being at bottom with an inclined lower portion as at b (either a
double incline as in figure 2 or a single incline as in figure 2*) for the purpose of
allowing ash to drop clear from them without clogging them and so maintain clear

page_text: passages for the air supply. The bars should be set apart to such a distance that
the total area of the spaces between the portions of the bars upon which the fuel
rests is as great as is possible consistently with the necessary strength of the bars.
If the said bars be set apart at such a distance as to give a total air space of
about 70 per cent of the total grate surface, a good effect will be obtained. Owing
to the large per centage of air space to the grate surface the bars can be made
much thinner than has hitherto been the case, for example, they may be of a
thickness of about a quarter of an Inch at top tapering to one eighth of an inch at
the lowest part and with transverse openings one quarter of an inch in width at
top and three quarters of an inch apart, the said bars being set a quarter of an
inch apart. Bars thus proportioned are especially suitable for furnaces wherein
the bars are not subjected to heavy strains, such for example as the furnaces of
Locomotives or the like.
For ordinary metallurgical furnaces or other furnaces subject to great strains the
bars should be thicker, say half an inch thick, tapering down to a quarter of an
inch and being set about five sixteenths of an inch apart.
For furnaces of Cornish,
Lancashire or Marine Boilers generally and for furnaces of a like kind, bars of
different thicknesses may be used at different parts of the furnace, the said bars
being situated at such parts of the grate as may be rendered desirable by the
intensity of the draught at different parts.
In making up the grate with fire bars constructed as herein before described, the
transverse passages a of all the bars may be in line but we prefer to arrange the
said passages so that those in cach bar are opposite to the solid portions between
the said passages of the bars adjacent thereto. The fire door end of the furnace
above the fire bars should be without air openings so as to prevent cold air from
gaining admittance to the furnace from above the fuel. The air for the combustion
of the fuel on the bars is supplied from the ash pit, the said air passing to the fuel
by the before named spaces between and in the bars.
We do not limit ourselves to the precise proportions hereinbefore stated as they
may be varied. Figure 2b shews a variation which may be adopted: the openings a
are in this form farther apart than in the bar shewn in Figure 1, but the two
forms of bar in their essential features resemble each other. The bridge above the
fire-bars is preferably constructed or formed with an opening or openings, the sides
and top of which form a superheating surface for the products of combustion
passing therethrough and the said opening or openings deliver the gases in a
compact body through the bridge. For Cornish or Lancashire or like boilers,
there should be an opening or openings through the bridge at each side, as shewn
in the Drawing where the passages are marked c.
In order to burn the superheated unconsumed combustible gases which have
passed through or over the bridge, an air passage or passages is or are made in the
lower part of the bridge or back wall of the ash pit, each such passage being
provided with a pipe as at d, opening behind the bridge in line with the opening
or openings by which the gases pass on their way to the Chimney so as to deliver
the air into the midst of the unconsumed gases and preferably in the direction of
the draught to the chimney. By this means, the Oxygen from the air is brought
into direct contact with the super-heated unconsumed gases, which have not been
previously injuriously diluted by air admitted above the fire-bars, and by this
means, the said Gases are practically entirely burned and the whole of the caloric
generated by the combustion of the fuel is thus utilized. The air opening or
openings is or are provided with a valve or valves or damper or dampers for
example as at e which can be operated from the exterior of the furnace so as to
regulate or cut off the supply of air to the back of the bridge as desired.
Where two or more furnaces are employed together in order to prevent the
formation of smoke whilst charging the furnaces with fuel owing to the inlet of air
by the furnace door it is preferred to provide a damper in the tube of each furnace
each damper being so connected to the door of the corresponding furnace by an
arrangement of levers and rods or the like that on the door being pened the

page_text: damper will be automatically closed or partially closed to be again automatically
opened when the furnace is closed.
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed we declare that what
we claim is
First. Forming fire grates of furnaces for steam boilers or other beating purposes
of bars tapering in cross section and with transverse air spaces in the upper part
so formed or arranged as to give a clear drop for the ash and maintain a passage
for air therethrough substantially as hereinbefore described and illustrated in the
accompanying drawings.
Second-In furnaces for steam boilers or other heating purposes the combination
of the bars claimed by the preceding claiming clause with means for supplying a
regulated quantity of air into the midst of the unconsumed gases which have
passed over or through the bridge substantially as herein before described and
illustrated in the accompanying drawings.
Third-In furnaces for steam boilers or other heating purposes the combination
of the bars claimed by the preceding first claiming clause with a fire bridge or
partition having above the fire bars an opening or openings therethrough to
superheat the combustible gases passing therethrough and with means for
supplying a regulated quantity of air into the midst of the said gases after they
have passed through the said opening or openings substantially as herein before
described with reference to the accompanying drawings.
Fourth-The arrangement and combination of parts constituting the furnace as
herein before described with reference to the accompanying drawings.
Dated this 30th day of September One thousand eight hundred and eighty four,