IMPROVEMENTS IN BOILER AND OTHER FURNACES to be as follows:
Year: 1884

page_text: We, ROBERT WELFORD, of Hunters Hall, Durham Road, Sunderland, in the
County of Durham, Engineer, and WILLIAM WELFORD of 3 Park Terrace,
Sunderland, Engineer, do hereby declare the nature of said invention for
"IMPROVEMENTS IN BOILER AND OTHER FURNACES to be as follows:-
"
This invention of improvements in boiler and other furnaces has for object to
effect more perfect combustion of fuel and thereby to produce from a given
quantity of fuel more heat than has heretofore been usual with furnaces of the
ordinary construction in which the air to effect combustion of the fuel is admitted
through the ash-pit and thence ascends between the fire bars or their equivalent
and through the fuel resting thereon to effect its combustion.
Now according to this invention instead of air being admitted from beneath the
fuel through the ash-pit it is caused to pass (in a more or less heated state) down-
ward through the fuel into the ash-pit which is provided with one or more
air-tight doors. From the ash-pit the products of combustion proceed to the boiler
flue, tubes or flues, or other desired place (to be utilized) through suitable openings
provided for the purpose in the back portion of the ash-pit. It will be obvious
that this invention may be carried out in various ways. In one arrangement a
combustion chamber of suitable form provided with fire-bars or their equivalent
and an ash-pit is provided with double air-tight doors at its front end-At or near
the back one or more openings is or are formed communicating with the boiler
flue, tubes, or flues or other desired heating surface. Beneath the ash-pit is or are
one or more air flues having at the outer end or ends a valve or valves or damper
or dampers or other suitable means for regulating the amount of air admitted, such
flue or flues extending beneath the ash pit to its back and there ascending to the
combustion chamber at what is usually known as the fire-bridge end. In this
manner air admitted to the air flue or flues becomes more or less heated in its
passage to the fuel by contact with the heated surfaces of the ash-pit, combustion
chamber and adjacent parts whereby it will effect the combustion of the fuel at
a higher temperature than is the case when cold air is admitted direct, as is well
understood. The flame and hot products of combustion pass into the ash-pit and
thence through the opening or openings above mentioned to the boiler flue or other
desired place as above stated.

page_text: This invention may be applied to externally or internally fired boilers and the
ash-pit, fire bridge and fire bars may be constructed of any materials suitable for
such purposes and, as will be evident these parts may be constructed to form parts
of the boiler itself to which the invention is applied. Also instead of employing
one set of fire bars or their equivalent with its layer of fuel two or more sets may
be used.
The heating surfaces for the air, gas, etc employed in carrying out this invention
may consist of numerous small flues or passages or the surfaces may be corrugated.
Although in the foregoing description air only is referred to, it will be evident a
gas or gases may be introduced in the same manner.
.

page_text: We, ROBERT WELFORD of Hunters Hall Durham Road, Sunderland in the
County of Durham Engineer and WILLIAM WELFORD of 3 Park Terrace
Sunderland, Engineer do hereby declare the nature of our invention for IMPROVE-
MENTS IN BOILER AND OTHER FURNACES, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
Our Invention of improvements in Boiler and other Furnaces has for object to
effect more perfect combustion of Fuel and thereby to produce from a given
quantity of Fuel, more heat than has heretofore been usual with Furnaces of the
ordinary construction, in which the air to effect combustion of the Fuel is principally
admitted through the Ashpit and thence ascends between the Firebars or their
equivalent and through the Fuel resting thereon to effect its combustion.
Now according to this invention instead of air being admitted from beneath the
Fuel through the Ashpit, it is caused to pass in a more or less heated state down-
wards through the Fuel into the Ashpit, which is provided at its front end with
one or more air-tight doors; under the Ashpit more air is admitted to complete
combustion and the products of combustion proceed to the Boiler Flue, Tubes or
Flues, or other desired place (to be utilized) through suitable openings or chambers
provided for the purpose at the back of the Ashpit, by and in which the heat is
regenerated and diffused.
We will now proceed to describe our invention by the aid of Drawings:-
Fig. 1. is a front elevation of a marine or land Boiler Furnace for ordinary use.
Fig. 2. is a horizontal sectional plan on the line M. N. of Fig. 1.
Fig. 3. is a vertical transverse section on the line X. Y. of Fig. 2.
Fig. 4. is a longitudinal section on the line P. R. of Fig. 1. & shewing grate.
Fig. 5. is a front elevation of a Cornish or Flue Boiler Furnace.
Fig. 6. is a horizontal sectional plan on the line M. N of Fig. 5.
Fig. 7. is a vertical transverse section on the line X. Y. of Fig. G.
Fig. 8. is a longitudinal section on the line P. R. of Fig. 5.
Like Figures and letters indicate similar parts throughout the Drawings.
F. is the Furnace Front having fixed in it the Fire door a., the Air Doors a¹, and
the Ash pit Doors b.
A. are the Air Flues, chambers & passages; all are linings of Fireclay or other
refractory material above the grate for maintaining the heat of the Fire & conducting
heat to Boiler Plates; all is the Firebridge acting also as additional grate if
required.
D. is the grate, whereon the solid fuel rests and thus causing the whole surface
of the Fuel to be exposed for air.
B is the Ash pit lined with Fire clay or other refractory material b', and into
which more air is supplied in order to consume the combustible gases.
C. are the chambers for the regeneration of the heat also made of Fireclay or
other refractory material.
G. are the Flues or other desired places wherein the resultant heat is directly
utilized.
In Figs. 1. 2. 3. 4 the furnace Fronts F. are made of Cast Iron or other suitable
material. The Firedoor a. at the Top has venetians a' fixed in it, in order to
regulate the admission of the air to the top of the Fuel (the venetians also intercept
the greater part of the heat which would otherwise radiate into the stokehole).
Tho Furnace plates of the Boiler proper are lined with some refractory material a¹¹

page_text: in order to prevent the cooling of the Fire and the flame and hot gases which
proceed through the grate D. meet more air in the Ashpit B. the said air entering
through suitable orifices from the flue A, below the Ashpit, also through additional
passages formed by iron tubes or otherwise in centre of Fireclay Bars as shewn in
Figs 3 & 4. At the back of the Ashpit are openings or chambers C constructed of
brickwork in order to regenerate the heat, which then passes into G or other
places to be utilized.
In Figs 5. 6. 7. 8 the air flue A underneath the Ashpit B has the door, valve or
damper a¹ which regulates the supply of air and the air becomes much heated by
contact with the sides of the Flue. Part of the air ascends at the back and then
spreads over and unites with the incandescent Fuel resting on the grate D and the
resulting flame and hot gases then pass down through the grate into the Ashpit B
where more air for the combustion of the gases is supplied through suitable openings
in the before mentioned air Flue A situated underneath the Ashpit and extra air
may be supplied through the hollow Fireclay Bars.
At the back of the Ashpit the openings and chambers C are formed for regene-
rating the heat, communicating with the Boiler flue G.
The Bridge a Figs 2. 3. 4 is here shewn with perforations in order to give
additional grate when required, but may usually be dispensed with. This Bridge
may also be made a water bridge if considered desirable & forming part of the
Boiler proper.
-
The Grate D might also be composed of Tubes containing water and attached to
the Boiler or otherwise.
We prefer the openings C and partitions C¹ to be formed of a number of Firebricks
as a Regenerator and this can be well applied to Land Boilers. We also prefer our
system to be used with forced draught.
"
In the case of externally fired, water tube and plain cylindrical egg-ended Boilers
or any other process by which this Furnace might be required, it is obvious this
invention would be constructed outside, underneath or apart from the said Boilers
or hot chambers where the resultant heat from this Furnace had to be applied and
the said Furnace might be constructed wholly of Brickwork and be placed in any
desired position.
It is obvious the grate may be made either with one or more sets of Bars and
the said Bars or their equivalent may be any depth and may be placed diagonally
or at any angle in the Furnace or across the Furnace.
The Air Flue A below the Ashpit may also be made of a number of flues, channels
or pipes so as to give more heating surface if desired & the quantity or current inay
be regulated as desired.
Having now particularly described and ascertained the nature of our invention
& in what manner the same is to be performed we declare what we claim is :-
1st Introducing & heating the air by means of a Flue or Flues situated
underneath or outside the Ashpit in combination with down draught substantially
as described.
2nd The admission of air from beneath the Ashpit to burn the combustible gases
in combination with down draught substantially as described.
Dated this 6th day of November 1884.