IMPROVEMENT IN BOILER FURNACES
Year: 1885

page_text: I, ALEXANDER HENRY REED, of Suffolk House, Laurence Pountney Hill, Cannon
Street, in the county of Middlesex, Engineer, do hereby declare the nature of said
invention for IMPROVEMENT IN BOILER 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 consists in the combination with a boiler and with a furnace of
air pipes, air distributers at the sides of the furnace in front of the bridge wall
and connections between the air pipes and the air distributer; and also in the
combination with a steam boiler and with a furnace of air pipes, an air distributer
in the combustion chamber of the furnace and connections between the air pipes
and the air distributer.
By this invention thorough combustion and saving in fuel are obtained.
In the accompanying drawing
Fig. 1 is a longitudinal vertical section of a steam boiler furnace embodying
the invention.
Fig. 2 is a transverse vertical section in the plane x x fig. 1.
Fig. 3, is a similar section in the plane y y fig. 1.
Similar letters indicate corresponding parts.
In this drawing the letter A designates a boiler provided with fire tubes a, B is
the grate, C is the ash pit, D is the bridge wall, and D¹ the combustion chamber all
constructed as usual. E are air pipes or tubes extending through the boiler.
One
end of each of said air pipes or tubes E communicates with the open air or with
any suitable supply of air, or air can be forced or introduced into the said air pipes
or tubes E in any suitable manner.
The other end of each of the air pipes or tubes E connects by suitable connections
as for example by pipes F and joints or elbows b, c, with air distributors G.
The air distributors G can be formed by boxes or shells of cast metal or any
other suitable material.
The air distributers G are placed on each side of the furnace H. The air
distributers G being placed within the wall surrounding the boiler A, are not

page_text: "
liable to be injured by the heat of the furnace, and they do not interfere with the
introduction of fuel into the furnace H. The fuel can be introduced through the
furnace door I and access can be had to the ash pit by means of the door K.
By providing the air distributer G on the sides facing the furnace with
perforations or openings, the air coming to the distributer from the air pipe or
tube E is supplied to the furnace H and secures a thorough consumption of the
fuel in the furnace, which will secure heating of the boiler with a less amount of
fuel than when the fuel is but partly consumed, and saving of fuel is effected.
As the air distributers G are in front of the bridgewall D, the air on issuing
from the distributors G is in the immediate presence of the combustion going on
in the furnace H and will thus secure a thorough combustion. The air pipes or
tubes E extending through the boiler will become heated so that the air passing
through pipes E is heated when issuing from the distributers G and the furnace H
is not cooled by the air from the distributers G. As cooling of the furnace and of
the products of combustion may retard the heating of the boiler A it is well to
avoid such cooling.
By providing the distributers G with a large number of small perforations, the
air issues from the distributers G in fine streams, thus securing a thorough action
of the air upon the gaseous products of combustion. Of course the air pipe E
instead of passing through the boiler, may also be heated by being placed in
contact with or close to the exterior of the boiler A, but it is preferable to have
the pipe E to pass through the boiler.
In order to facilitate the combustion of the furnace gases in the combustion
chamber, means are provided for introducing heated and well distributed air into.
the said combustion chamber, and in the example shown in the drawing, an air
distributor O is situated in the combustion chamber D' directly behind the bridge-
wall D.
This air distributer O consists of a cylinder of metal or other suitable material
which is closed at both ends and is provided with a large number of perforations
through which the air passes into the combustion chamber. Separate air pipes
could be employed for this distributer O but as shown in the drawing the same is
connected with pipe F leading from the air pipe or tube E by pipes d, e, and
suitable joints and elbows. In order to avoid as much as possible the actual
contact of the hot gases with the air distributer O which might finally result in
the destruction of said air distributer, the same is placed in a free space P left
between the bridgewall D and the bottom or facing M of the combustion chamber.
The external air introduced into the combustion chamber D' whether so introduced
by the natural draught of the chimney or by means of an air forcing device is
heated as before during its passage through the air pipes or tubes E and is further
heated in passing through pipes d, e. It is not necessary to use separate tubes for
the air tubes E as for instance if the improvement is to be attached to any
ordinarily constructed tubular boiler and furnace, the pipes forming the connections
with the distributers G can be directly connected with one of the fire tubes of the
boiler, and said fire tubes are then used as air tubes for conducting air to the
distributers O and G.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is
1. The combination with a boiler and with the furnace, of air pipes E, air
distributers G at the sides of the furnace in front of the bridgewall D and
connections between the air pipes and the air distributers substantially as shown
and described.
2. The combination with a boiler and with the furnace of air pipes E extending
through the boiler, air distributers G at the sides of the furnace in front of the
bridgewall D and connected between the air pipes and the air distributers substan-
tially as shown and described,

page_text: 3. The combination with a boiler and with the furnace of air pipes E an air
distributer O, situated in the combustion chamber D¹ of the furnace and suitable
connections between the air pipes and the air distributer substantially as shown
and described.
4. The combination with a boiler and with the furnace of air pipes E, extending
through the boiler an air distributer O situated bebind the bridgewall D of the
furnace and suitable connections between the air pipes and the air distributer
substantially as shown and described.
5. The combination with a boiler and with the furnace, of air pipes E, air
distributers G G at the sides of the furnace in front of the bridge wall D an air
distributer O behind the bridgewall and connections between the air pipes and the
distributers G G and O substantially as shown and described.
6. The combination with a boiler and with the furnace, of air pipes E extending
through the boiler, air distributers G G at the sides of the furnace in front of the
bridgewall, an air distributer O in the combustion chamber and connections
between the air pipes and the air distributers G G and O substantially as shown
and described.