IMPROVEMENTS IN OR CONNECTED WITH BOILER OR OTHER FURNACES "
Year: 1882

page_text: LETTERS PATENT to William Mowatt of Kates Mill Slateford in the County
of Midlothian North Britain for an Invention of " IMPROVEMENTS IN OR
CONNECTED WITH BOILER OR OTHER FURNACES
"
PROVISIONAL SPECIFICATION left by the said William Mowatt at the Office,
of the Cominissioners of Patents on the 6th November 1882.
WILLIAM MOWATT, of Kates Mill, Slateford, in the County of Midlothian, North-
Britain, "IMPROVEMENTS IN OR CONNECTED WITH BOILER OR OTHER FURNACES,"
The object of this Invention is to prevent the formation in and emission from,
boiler and other furnaces, of smoke or unconsumed particles of carbon, and generally
to improve combustion of the fuel, and this object is effected by fitting in connection
with the doors of the furnaces a novel arrangement of appliances or devices
through which steam and air are injected over or into the burning fuel, and by
which the admission of the steam and air is regulated and controlled.
In carrying out the Invention as applied to an ordinary boiler furnace, the
furnace door is made hollow or formed with a channel or channels between the
front and the inner side of the door, extending vertically from the top to near tho
bottom where the passage or channels are by preference curved inwards; or the
channels may be formed Interally. The door when shut fits closely under an air
and steam chest fitted on the fixed door frame of the boiler flue, or to the boiler
face, and which consists of a hollow chamber, preferably of cast-iron, into which
air is admitted through openings in front, at the sides, or at the top or bottom.
Into this chamber are also fitted a pipe or series of steam pipes or jets projecting
towards the channel or channels in the door, and theso pipes are connected either
conjointly or separately with any steam connection from the boiler to which they
are applied, or from any other steam boiler, or as is preferred to a common cross
pipe to which steam is supplied by a pipe or tube leading from the steam space of
the boiler. To each steam jet pipe separately, or preferably by a single application
to the common steam supply pipe, or between the jets and the supply pipe, is
fitted either a steam cock to be worked automatically by the opening and closing

page_text: of the furnace doors, or preferably a valve which may be conical, or of any suitable
kind, closing by the pressure of the steam behind it. This valve is fitted with a
spindle passing out through a stuffing box in the pipe, and in contact with the
spindle is fitted a lever which is moved by the closing of the furnace door, and in
moving takes the valve off its seat to allow the steam to pass through the pipes
or jets. When the door is opened for firing, or for any other purpose, the lever is
disengaged and the steam valve closes to shut off the supply of steam. The
actuating valve lever may be moved by the top of the door, or by a projection on
it, or the valve may be directly actuated by an angled projection on the top, or any
other part of the door. When the steam is admitted through the cock or valve
and through the pipes leading towards the channel or channels or passages in the
furnace door, the jets of steam entering these passages, induce a flow of air through
the openings in the chamber enclosing the pipes, and the air and steam mix in
passing through the hollow door, and are injected through the aperture or
apertures at the bottom or other part of the door on to the dead plate and over or
into the burning fuel. The injection of steam and air into the furnace has the
effect, as is well known of consuming the smoke or proventing its formation, and
also of promoting combustion of the fuel.
In addition to the cock or valve arrangement for shutting off the supply of
steam automatically when the door of the furnace is opened, a hand valve or valves
may be fitted to the steam supply pipe or pipes; and it is also preferred to fit
over the openings through which the air is supplied, gratings or shutters, by means
of which the supply of air may be regulated, or entirely cut off: The door is by.
preference cast with the channels cored out; but the inner plate may be of wrought.
iron, and be secured to the ordinary door in such wise that a channel or series of
conical or other channels is formed for the injection of steam and air. The furnace
door is fixed to the front plate in the usual way.
In applying the Invention to other furnaces than those of steam boilers, the door
and the steam and air injecting appliances are made in a similar way to suit the
doorway of the furnace, and the injection steam is brought by pipes from a separate
boiler or generator.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Mowatt in the Great Seal Patent Office on the 4th May
1883.
WILLIAM MOWATT, of Kates Mill, Slateford, in the County of Mid Lothian, North
Britain IMPROVEMENTS IN OR CONNECTED WITH BOILER OR OTHER FURNACES
"
ม
The object of my said Invention is to prevent the formation in, and emission
from, boiler and other furnaces of smoke or unconsumed particles of carbon, and
generally to improve combustion of the fuel; and this object is effected by fitting
in connection with the doors of the furnaces a novel arrangement of appliances or
devices through which steam and air are injected over or into the burning fuel, and
by which the admission of the steam and air is regulated and controlled.
My said Invention is illustrated by the accompanying drawings in which figure 1
is a longitudinal vertical section of part of a boiler showing the improvod furnace
door and devices applied to the furnace. Figure 2 is a front elevation of the boiler
showing the furnace doors, one of which is open; and figure 3 is a horizontal
section of the front plate takon partly over and partly through the furnace doors.
In carrying out the Invention as applied to an ordinary boiler furnace, such as
that illustrated, the furnace door A is made hollow or formed with a channel or
channels a between the front and the inner side or plate A¹ of the door, and
extending vertically from the top to near the bottom where the passage or channels a
are by preference curved inwards as at a¹ or the channels a may be formed
laterally. The door A when shut fits closely under an air and steam chest B
fitted on the fixed door framo C of the boiler flue D, or to the front plate El of the
boiler E. This chest consists of a hollow chamber B, preferably of cast-iron, into
which air is admitted through a grating or openings 6 in front, at the sides, or at
the top or bottom. Into this chamber B are also fitted a pipe or series of steam
pipes or jets projecting towards the channel or channels a in the door A, and these
pipes fare connected either conjointly or soparately with any steam connection
from the boiler E to which they are applied, or from any other steam boiler, or as
is preferred to a common cross pipo F to which steam is supplied by a pipe or
tube F¹ leading from the steam space of the boiler E.
To each steam jet pipe f separately, or preferably by a single application to the
common steam supply pipe F, or between the jets f and the supply pipe F is fitted
either a steam cock to be worked automatically by the opening and closing of the
furnace doors, or preferably a valve f¹ which may be conical, or of any suitable
kind, closing by the pressure of the steam behind it. This valve f is fitted with a
spindle passing out through a stuffing box f³ in the pipe F, and in contact with
the spindle f is fitted a jointed lever G which is moved by the closing of the
furnace door, and which in moving takes the valve fl off its seat to allow the
steam to pass through the pipes or jets f. When the door A is opened for firing,
or for any other purpose, the lover G is disengaged and the steam valve f' closes
to shut off the supply of steam through the pipe F.
The actuating valve lever G, which is jointed to a bracket G² on the door frame C
may be moved by the top edge of the door A, or by a projection a³ on it, or the
valve fmay be directly actuated by an angled projection on the top, or at any
other part of the door A. When the steam is admitted through the cock or valve₤1,
and through the pipes leading towards the channel or channels or passages a in
the furnace door A, the jets of steam entering these passages induco a flow of air
through the openings b in the chamber B enclosing the pipes f, and the air and
steam mix in passing through the hollow door A, and are injected through the

page_text: aperture or apertures a' at the bottom or other part of the door on to the dead
plate H and over or into the burning fuel in the furnace E².
The injection of a mixture of steam and air into the furnace has the effect, as is
well known, of consuming the smoke or preventing its formation, and also of
promoting combustion of the fuel.
In addition to the cock or valve arrangement f¹ for shutting off the supply of
steam automatically when the door of the furnace is opened, a hand valve Fº is
fitted to the steam supply pipe or pipes F. It is also preferred to fit over the
openings b in the chamber B through which the air is supplied, gratings or shutters,
by means of which the supply of air may be regulated, or entirely cut off. The
door A is by preference cast with the channels a cored out; but the inner plate A¹
may be of wrought iron, and be secured to the ordinary door in such wise that a
channel or series of conical or other channels a is formed for the injection of steam
and air. The furnace door A is fixed to the front plate C in the usual way.
In applying the Invention to other furnaces than those of steam boilers; the
door and the steam and air injecting appliances described are made in a similar
way to suit the doorway of the furnace, and the injection steam is brought by
pipes from a separate boiler or generator.
Having now described the nature of my said Invention, and the manner in
which the same is to be performed, I declare that what I claim as my Invention
is,-
--
..
--
--
First. The arrangement and combination of parts of apparatus for injecting a
mixture of steam and air into furnaces, substantially as herein described and
illustrated.
Second. As means for facilitating the injection of a mixture of steam and air
into furnaces, the combination of the steam supply pipes F, F¹, and steam jets f
with the hollow door A substantially as hereindescribed and illustrated,
Third. The combination, substantially as herein described and illustrated; of the
hollow furnace door A, a, with the chamber B, b, fitted with steam jets f, and steam
supply pipes F, F', provided with a valve f' actuated by the opening and closing
of the furnace door for the purpose set forth.
In Witness Whereof, I, the said William Mowatt have hereunto set my
hand seal [sic] this second day of May, in the year of our Lord One
thousand eighthundred and eighty three,
WILLIAM MOWATT (L.S.)
WILLIAM MOWATT (LS)