Improvements in Gas Furnaces.
Year: 1892

page_text: Date of Application, 15th Jan., 1892
Complete Specification Left, 13th Oct., 1892-Accepted, 19th Nov., 1892
PROVISIONAL SPECIFICATION.
[Communicated from abroad by RICHARD NICKERSON OAKMAN, the Younger,
of Greenfield, in the State of Massachusetts, United States of America.]
Improvements in Gas Furnaces.
I, HENRY EDWARD NEWTON of the Offices for Patents, 6 Breams Buildings,
Chancery Lane, in the County of London, Patent Agent, do hereby declare the
nature of this invention to be as follows:-
This invention relates to a method and furnace for heating large sheets or plates
of metal, or other articles, by means of gas flames.
form a mufte.
The object of this invention is to provide for evenly and uniformly heating a
furnace of large horizontal area by gas flames passing alternately in opposite
directions both below and above the broad floor or hearth. The flames may be
first introduced below the hearth, and then passed above it to the escape flue, or
may be first passed above the hearth, over an interior crown, and then below the
hearth to the escape flues. In the latter case, the hearth may be enclosed so as to
In either case, it is preferable to introduce the flame upon opposite
sides of the hearth, and pass then alternately in opposite directions through
adjacent parallel flues, either below or above the hearth, and thence conduct the
waste products to the escape flues, either above or below the hearth. Uniform
heating is thus secured throughout the entire area of the broad hearth or heating
chamber, so that large metallic plates or sheets may be evenly heated, for tempering,
annealing, or other purposes, and improved results obtained. Fuel-gas is preferably
used, composed of water gas, or a mixture of water gas and producer gas, or it may
be, producer gas alone, and the gas intimately mixed with the air under pressure in
the burners.
The reheating furnace is constructed of refractory material usually employed in
building heating furnaces, and is provided with a broad hearth or floor in the
heating chamber, and with an arched crown supported upon the side and end walls.
Below the hearth is constructed a foundation floor, resting upon the bars or
columns. Upon the foundation floor is constructed a series of low longitudinal
division walls extending across from side to side of the furnace, and forming
parallel flues, which open upward alternately upon opposite sides of the furnace
between the side walls and the opposite bridge walls.
Burners are inserted in suitable ports. opening into the alternate Alues. The
flames and products from both sets of flues, pass up over lateral bridge walls, above
the hearth, and thence through ports in the crown of the furnace, and on upward
into a chamber of a heat restorer or air heater, supported on a frame above the
furnace.
The heat restorer preferably provided with a perforated arch, near its bottom,
forming below it a receiving and distributing chamber, which is preferably divided
by the transverse vertical partition plates, which serve to support the perforated
arch, but do not extend quite down to the main arch. The outlet ports, in the
crown of the furnace, are provided with sliding dampers, for controlling the pressure
within the working chamber and escape of hot gaseous products which rise into the
air heating chamber, for heating the air which is supplied to the coils of pipe.
These pipes may be round, but are preferably elliptical in cross section, and are
preferably arranged in horizontal rows, each of which acts as a unit. Cold airis
passed into all three of the top row of pipes at once; that is, into each pipe, and
thence passes down through all of the pipes in each row simultaneously, becoming
hotter as it passes along, and downward through the series, while the waste heated

page_text: products become cooled as they pass upward over the air pipes, and finally escape
at regulated outlet ports, at a comparatively low temperature.
The
For the purpose of heating and working brass and copper and all metals sensitive
to sulphurous gases, the muffle form of heating furnace is preferably used.
direct firing flues are formed between the muffle and the main arches, and this
space over the crown is divided into flues by means of partition walls or ribs. The
floor or hearth is supported by partition walls, forming parallel flues, which connect
alternately on opposite sides, by means of passages, with large flues which connect
by a flue with the air heating chamber. The air-heater in this case is formed by
a series of shaped pipes, arranged in a series of three or four. The hot gaseous
products pass through chamber in an opposite direction from the air which passes
through the heating pipes, so that the air is better heated, and the products escape
at a low temperature. With this mufle form of heater, the gas flames are
projected alternately in opposite directions through flues passing over the crown,
and thence through flues extending entirely across the furnace below hearth, so
that the flames and products are caused to pass entirely around the muffle chamber,
and uniformly heat it on all sides.
The operation of the furnace is simple, and it is very effective for reheating large
metal plates and similar articles. The jets of mixed gas and air are ignited at the
burners, the flames being projected alternately in opposite directions through flues,
and thence passing over the bridge walls, over the hearth, and out through the
escape ports, through which they pass into the air heater, and heat the incoming
air, which is forced through the pipes. On account of the large area of these
reheating furnaces, the gas flames or other heating medium admitted on one side
only, would not uniformly and thoroughly heat them, since the flames are the
hottest near the inlet ports, and gradually lose their temperature as they pass to the
opposite side of the furnace. By arranging the burners on opposite sides of
the furnace, and causing the flames to pass alternately in opposite directions, but
both sets maintained at the same time, the difficulty heretofore experienced is over-
come, and the furnace and the metal plates placed therein are thus evenly heated.
By evenly heating the furnace, moreover, it is relieved from strain and unusual
expansion, and is therefore less likely to get out of repair.
Dated this 15th day of January 1892.
NEWTON & SON,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Gas Furnaces.
I HENRY EDWARD NEWTOx of the Office for Patents, 6 Bream's Buildings
Chancery Lane in the County of London, Patent Agent, do hereby declare the
nature of this invention 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 a method and furnace for heating large sheets or plates
of metal, or other articles, by means of gas flames.
The object of this invention is to provide for evenly and uniformly heating a
furnace of large horizontal area, by gas flames passing alternately in opposite
directions, both below and above the broad floor or hearth. The flames may be
first introduced below the hearth, and then passed above it to the escape flue, or
may be first passed above the hearth, over an interior crown, and then below the
hearth, to the escape flues. In the latter case, the hearth may be enclosed so as to
form a muffle.
In either case it is preferable to introduce the flames upon opposite
sides of the hearth, and pass them alternately in opposite directions through
adjacent parallel flues, either below or above the hearth, and thence conduct the
waste products to the escape flues either above or below the hearth. Uniform
heating is thus secured throughout the entire area of the broad hearth or heating

page_text: cuamber, so that large metallic plates or sheets may be evenly heated for tempering,
annealing, or other purposes, and improved results obtained. Fuel gas is preferably
used composed of water gas, or a mixture of water gas and producer gas, or it may
be producer gas alone, and the gas intimately mixed with the air under pressure in
the burners.
In the accompanying drawings,
Fig. 1 represents a vertical longitudinal section of the furnace on line 2, 2, Figs. 2
and 3.
Fig. 2 represents a horizontal section on line y y. Fig. 1.
Fig. 3 represents a transverse section on line, Figs. I and 2.
Fig. 4 represents a longitudinal section similar to Fig. 1, of a modified form of
furnace and air heater.
The reheating furnace A is constructed of refractory material usually employed
in building heating furnaces, and is provided with a broad hearth or floor B in the
heating chamber, aud with an arched crown C supported upon the side and end
walls. Below the hearth B, is constructed a foundation floor D, resting upon the
bars or columns Y. Upon the foundation floor D is constructed a series of low
longitudinal division walls, extending across from side to side of the furnace, and
forming the parallel flues & and d, which open upward alternately upon opposite
sides of the furnace, between the side walls and the opposite bridge walls band b¹,
constructed on each side of the hearth B, as shown in Figs. 1, 2, and 3.
The arrows 1 and 2, Figs. 1 and 2, indicate the direction of the flame and products
issuing from the flues & and ', upon opposite sides of the hearth B. The division
walls are indicated partly by dotted lines, and partly by full lines in Fig. 2. Upon
the left hand side of the furnace, the burners a are inserted in suitable ports o
opening into the alternate flues d, which open upward upon the right hand side of
the furnace, as shown in Figs. 1 and 2, so that the flames are projected towards the
right hand side through all the flues d.
Upon the right hand side of the furnace, burners a' are inserted in similar ports o
opening into the alternate flues d', which open upward upon the left hand side of the
furnace as shown in Fig. 2, so that the flames from such burners a are projected
from right to left through all the flues . The flames and products from both sets
of flues, pass up over lateral bridge walls, above the hearth B, and thence
through the ports c c in the crown of the furnace C, and on, upward, into the
chamber E of the heat restorer or air heater E supported upon a frame X above
the furnace A.
The heat restorer E is preferably provided with a perforated arch e, near its
bottom, forming below it the receiving and distributing chamber E. Chamber E¹
is preferably divided by the transverse vertical partition plates e', which serve to
support the perforated arch e, but do not extend quite down to the arch C. The
outlet ports cc in the crown of the furnace are provided with sliding dampers hh,
for controlling the pressure within the working chamber and escape of hot gaseous
products which rise into the air heating chamber E for heating the air which is
supplied to the coils of pipe H. These pipes may be round, but are preferably
elliptical in cross section, as shown in Fig. 3, and are preferably arranged in
horizontal rows, each of which acts as a unit. Cold air is passed into all three of
the top row of pipes at once, that is, into each pipe, and thence passes down through
all of the pipes in each row simultaneously, becoming hotter as it passes along and
downward through the series, while the waste heated products become cooled as
they pass upward over the air pipes, and finally escape at the outlet ports, at a
comparatively low temperature. The ports are provided with sliding dampers
for controlling the escape of waste products.
Pipes lead from the air heater H, and connect by service pipes i, having
valves, with the burners a and a. The main gas supply pipes connect by
service pipes, having valves, with the burners a and a. Both the gas and air
are supplied to the burners under substantially the same pressure, and are intimately
mixed within the burner shells before issuing therefrom.

page_text: For the purpose of heating and working brass and copper, and all metals
sensitive to sulphurous gases, the muffle form of heating furnace shown in Fig. 4 is
preferably used, which contains the enclosed muffle chamber A', having the
hearth B, and the interior enclosing crown or arch C. The direct firing flues d
and d are formed between the archies C and C. The space over the crown C¹ is
divided into flues & and d¹ by means of partition walls or ribs n', extending from
arch C nearly to the external arch C, for the purpose of allowing the muffle crown
or arch to expand. The floor or hearth B is supported by partition walls n, forming
parallel flues, which connect alternately on opposite sides, by means of passages j
and, with the large flues J and J, which connect by flue K with the air-heating
chamber E. The air-heater in this case is formed by a series of U-shaped pipes W
arranged in a series of three or four. The hot gaseous products pass through
chamber E2 in an opposite direction from the air which passes through the heating
pipes W, so that the air is better heated, and the products escape at a low tempera-
ture. With this mufte form of heater, the gas flames are projected alternately in
opposite directions through flues passing over the crown C, and thence through
flues extending entirely across the furnace, below hearth B, so that the flames and
products are caused to pass entirely around the muffle chamber A', and uniformly
heat it on all sides. Where only a moderate temperature, such as a red heat, is
required, producer gas can be burned with satisfactory results. The end walls of
the furnace A in Figs. 1, 2, and 3, are arched, so as to form wide openings m, which
in practice are closed by suitable doors for inserting and withdrawing the metal
plates.
The operation of the furnace is simple, and it is very effective for reheating large
metal plates and similar articles. The jets of mixed gas and air are ignited at the
burners a and a', the flames being projected alternately in opposite directions
through flues d and d¹, and thence passing over the bridge walls and b', over the
hearth B, and out through the escape ports c, c, through which they pass into the
air heater, and heat the incoming air, which is forced through the pipes H, all as
indicated by the arrows 1 and 2. On account of the large area of these re-heating
furnaces, the gas flames.or other heating medium admitted on one side only, would
not uniformly and thoroughly heat them, since the flames are the bottest near the
inlet ports, and gradually lose their temperature as they pass to the opposite side
of the furnace. By arranging the burners on opposite sides of the furnace, and
causing the flames to pass alternately in opposite directions, but both sets maintained
at the same time, the difficulty heretofore experienced is overcome, and the furnace
and the metal plates placed therein are thus evenly heated. By evenly heating
the furnace, moreover, it is relieved from strain and unusual expansion, and is
therefore less likely to get out of repair.
Great economy in the use of the gaseous fuel is secured by this furnace and
method of operating it, and improved results in uniformly heating the metal plates
are secured.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me from
abroad, I declare that what I claim is:
1. The method of heating a furnace for reheating metal plates and other articles,
which consists in passing the flames and hot products at the same time from
opposite sides of the furnace in opposite directions, in contact with the heating
chamber, whereby the chamber is uniformly heated, and improved results secured.
2. The method of heating a furnace for reheating metal plates or other articles,
which consists in simultaneously passing the flames and hot products alternately in
opposite directions through the flues adjacent to the heating chamber, whereby said
chamber is uniformly heated, and improved results secured.
3. A heating furnace constructed with a series of flues extending across, and
opening upon, opposite sides thereof, said flues being provided with a series of
burner ports and burners on opposite sides of the furnace, adapted to project flames

page_text: and hot products in opposite directions in contact with the heating chamber, the
furnace also having an escape fluc, substantially as described.
4. A heating furnace constructed with a series of flues extending across, and
opening alternately upon, opposite sides thereof, the alternate flues being provided
at their inlet ends upon opposite sides of the furnace, each with a series of
burner ports and burners adapted to project flames and hot products alternately
in opposite directions in contact with the heating chamber, the furnace also having
one or more escape flues for waste products, substantially as described.
5. A heating furnace A, constructed with a hearth B, the bridge walls and b
at opposite sides thereof, the flues d and d below the hearth, and opening alternately
upon opposite sides of the furnace between the side walls and said bridges, said
flues & and being provided with burner ports and burners at their inlet ends,
alternately upon opposite sides of the furnace, and escape flues for waste products,
substantially as described.
6. A. heating furnace constructed with a series of combustion or heating flues
extending across, and opening upon opposite sides thereof, and provided with scries
of burner ports and burners on opposite sides of the furnace, in combination with a
heat restoring chamber containing air-heating pipes, and escape flues connecting
the heating furnace with the heat restoring chamber, substantially as described.
Dated this 13th day of October 1892.
NEWTON & SON,
Agents for the Applicant.