IMPROVEMENTS IN APPARATUS CONNECTED WITH BOILERS AND FURNACES TO EFFECT ECONOMY IN THE CONSUMPTION OF FUEL
Year: 1876

page_text: LETTERS PATENT to John Thomas, of Middlesbrough, in the County of York,
Engineer, for the Invention of "IMPROVEMENTS IN APPARATUS CONNECTED
WITH BOILERS AND FURNACES TO EFFECT ECONOMY IN THE CONSUMPTION OF
FUEL."
Sealed the 9th September 1876, and dated the 13th July 1876.
PROVISIONAL SPECIFICATION left by the said John Thomas at the Office of
the Commissioners of Patents on the 13th July 1876.
JOHN THOMAS, of Middlesborough, in the County of York, Engineer. "IMPROVE-
MENTS IN APPARATUS CONNECTED WITH BOILERS AND FURNACES TO EFFECT ECONOMY
IN THE CONSUMPTION OF FUEL."
C
My Invention relates to heating air by and with the waste heat, and conducting
the heated air to the back of the bridges of the boiler fires, or through the same, so
that the heated air may meet the hot gases in its passage over the bridges of such
fire-places, and further combust the same.
For metallurgical and chemical furnaces I conduct the heated air into the flue for
the further combusting of the hot gases and smoke that pass through the heating
chamber.
.
For boilers of steam ships I construct the furnaces in the usual manner (except
that in some cases I make the flues and chimney larger), and I fix in the flues, and
if needed in the chimney, a series of pipes or passages connected together so as to
make one continuous passage. Or I fix an air casing around the chimney up to
about 10 or 12 feet of its height, and fix cross tubes through the chimney. I also
make an air space the whole length of the smoke box. I connect with one or more
pipes the air spaces of the smoke box and chimney with the fires of the boilers by
conducting the same into or against the fire bridges. I then connect the inlet with
an air blowing machine, and I prefer for this purpose to use an exhausting blow-
ing fan machine; the inlet of such machine may be conducted to any part of the
ship for ventilating the same. When all the pipes and air spaces are connected to
the blowing machine at one end, and to the fire-bridges or fire-places at the other
end, and the fires lit in the boilers, I then, either by hand or steam power, set the
blowing machine in motion, and thus send a current of air through the pipes to be.
heated that the hitherto wasted heat may be taken up with the air and returned'
to the boiler, where it will issue against or through the fire-bridges, so that the
[Price Gd.l

page_text: heated air shall meet the hot gases in its passage over the fire-bridges, further
combusting the same in the boilers. If there are no bridges to discharge the hot
air against, then the heated air is propelled over the fires so as to further combust
the smoke and gases evolving from the fires.
To burn the smoke and gases evolving from stationary or land boilers I place one
or more pipes in the flues or in the chimney, and send a current of air through such
pipes to be heated, and lead the heated air through pipes to the bridges of the fire-
places of the boilers to combust the smoke and gases. In most cases this must be
done with a blowing machine if the-boilers are set high enough. I then reverse
the orifice of the air pipe in or near the fire-bridge, letting it out with the current,
in which case it will even without a blast abate the smoking and economize fuel.
For locomotives and vertical boilers that are burning coal or other smoke pro-
ducing material I heat the air with the chimney and flucs, and send the heated air
into the fire-box over the fire to combust the smoke and gases.
And for metallurgical and chemical furnaces I heat the air with the waste heat
either in pipes or passages constructed in the sides of such furnaces, or in the
chimneys or flues, or in any part where it is most convenient, and pass the heated
air into or near the flue so as to consume the smoke and gases that pass through the
heating chamber unconsumed; this heat may be applied to raising steam in a boiler
or for any other useful purpose.
In all of the above cases I regulate the quantity of air delivered to the furnace
with a valve or cock in each delivery pipe.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Thomas in the Great Seal Patent Office on the 13th January
1877.
"IMPROVE-
JOHN THOMAS, of Middlesbrough, in the County of York, Engineer.
MENTS IN APPARATUS CONNECTED WITH BOILERS AND FURNACES TO EFFECT ECONOMY
IN THE CONSUMPTION OF FUEL."
This Invention relates to heating air by and with the waste heat, and conducting
the heated air to the back of the bridges of the boiler fires, or through the same or
over the fires, so that the heated air may meet the hot gases in its passage over the
bridges of such fire-places, and further combust the same.
For metallurgical and chemical furnaces I conduct the heated air into the flue
for the further combusting of the hot gases and smoke that pass through the heating
chamber.
For boilers of steam ships I construct the furnaces in the usual manner, except
tliat in some cases I make the flues and chimney larger, and I fix in the flues, and
if needed in the chimney, a series of pipes or passages connected together so as to
make one continuous passage. Or I fix an air casing around the chimney up to
about 10 or 12 feet of its height and fix cross tubes through the chimney, I also make
an air space the whole length of the smoke box. I connect with one or more pipes
the air spaces of the smoke box and chimney with the fires of the boilers by
conducting the same into the furnace or against or through the fire-bridges. I then
connect the inlet with an air blowing machine, and I prefer to use for this purpose
an exhausting blowing fan machine. The inlet of such machine may be conducted
to any part of the ship for ventilating the same. When all the pipes and air spaces
are connected to the blowing machine at one end, and to the fire-bridges or fire-places
at the other end, and the fires lit in the boilers, I then, either by hand or steam
power set the blowing machine in motion, and thus send a current of air through
the pipes to be heated that the hitherto wasted heat may be taken up with the air
and returned to the boilers where it will issue into the furnace or through the fire-
bridges, so that the heated air shall meet the gases in its passage over the fire-
bridges, further combusting the same in the boilers. If there are no bridges to

page_text: discharge the hot air against then the heated air is propelled over the fires so as to
further combust the smoke and gases evolving from the fires.
To burn the smoke and gases evolving from stationary or land boilers I place
one or more pipes in the flues or in the chimney, and send a current of air through
such pipes to be heated, and lead the heated air through pipes to the furnaces or
bridges of the fire-places of the boilers to combust the smoke and gases. In most
cases this must be done with a blowing machine if the boilers are set high enough.
I then reverse the orifice of the heated air pipe either in the front of fire-place or
near the fire-bridge, letting it out with the current, in which case it will even
without a blast abate the smoking and economize fuel.
For locomotives and vertical boilers that are burning coal or other smoke
producing material I heat the air with the chimney and flues, and send the heated
air into the fire-box over the fire to combust the smoke and gases.
And for metallurgical and chemical furnaces I heat the air with the waste heat
either in pipes or passages constructed in the sides of such furnaces, or in the
chimney or flues, or in any part where it is most convenient, and pass the heated
air into or near the flue-bridge so as to consume the smoke and gases that pass
through the heating chamber unconsumed; this heat may be applied to raising
steam in a boiler or for any other useful purpose.
In all the above cases I regulate the quantity of air delivered to the furnaces
with a valve or cock in each delivery pipe.
In the accompanying Drawings, Figures 1 and 2 show plan and sectional elevation
of a metallurgical furnace with my means of directing heated air into the front of
the chambers and behind the furnace so that the heated air may commingle with
the products of combustion and be utilized for heating the metal. The air
(atmospheric) is caused to pass by the pipe A into the branch B, thence into a
chamber C, from which it passes through a series of openings D in the bridge E, as
shown. Sometimes I fit a second branch F in the after bridge G for a further
charging of the escaping gases and products of combustion, should they be utilized
in any way before passing out of the chimney.
Figures 3 and 4 show a marine boiler in section and face view, the air heating
tube being in spiral form in the uptake H, so as to be heated by the escaping gases,
the heated air being conveyed down to the front of the furnaces by the branches
to assist the draught and to promote combustion.
Figures 5 and 6 show a land boiler, the air heating pipes being in the chimney in
an up-and-down form, and fed from the outside I, the branch being carried from
the rear of the flue J to the front bridge F, in which is the chamber for distributing
the heated air in the manner described.
Figure 7 represents a chimney in section with ring or spiral air heating tubes,
having cross tubes K as connections, in order that the uprising gases may impinge
and impart their heat to them, and so increase the rarefaction of the air within
them prior to passing down, or along to the furnace bridge.
And having now described the nature of my said Invention, and in what manner
the same is to be performed, I declare that I claim, the heating the air with the
waste heat as described, and conducting the heated air into the furnace, either over
the fire or through the bridge or necks, according to the shape and the use of such
furnaces for the combustion of smoke and gases, and thereby saving fuel, as set forth
and substantially as shown in the annexed Drawings.
In witness whereof, I, the said John Thomas, have hereunto set my hand
and seal, this Twelfth day of January, One thousand eight hundred and
seventy-90
JOHN THOMAS. (L.S.)