IMPROVEMENTS IN APPARATUS FOR HEATING AIR AND GASES
Year: 1872

page_text: LETTERS PATENT to Thomas Whitwell, of Thornaby Iron Works,
Stockton-on-Tees, in the County of Durham, for the Invention of
"IMPROVEMENTS IN APPARATUS FOR HEATING AIR AND GASES."
Sealed the 16th July 1872, and dated the 19th January 1872.
PROVISIONAL SPECIFICATION left by the said Thomas Whitwell at the
Office of the Commissioners of Patents, with his Petition, on the
19th January 1872.
P
I, THOMAS WHITWELL, of Thornaby Iron Works, Stockton-on-Tees, in
the County of Durham, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN APPARATUS FOR HEATING AIR AND GASES," to
be as follows :—

page_text: The apparatus described in the Specification of the said Patent consists
of two furnaces, ovens, or chambers, each enclosed by four upright walls
contained in an iron case, and divided by upright parallel walls into
several narrow compartments. The walls are constructed with openings
alternately at the top and bottom so that the air and gas passing the
furnace, oven, or chamber is led alternately over and under the walls.
The furnace, oven, or chamber is first heated by admitting gas and air,
and burning them as they traverse the compartments, and then after-
wards the air to be heated for the blast is forced through the furnace,
oven, or chamber in the contrary direction.
According to my present Invention I form the furnace, oven, or
chamber and the iron caso which contains it of a properly cylindrical
form, with transverse partition walls and longitudinal walls to stay and
support the partition walls. In this way a considerable increase of
strength is obtained and the construction is facilitated.
I also form zig-zag passages in the partition walls, and pass through
the passages the air for burning the gas so that it becomes highly heated
before it meets the gas in the furnace, oven, or chamber. In this way a
more intense combustion is obtained. The furnace, oven, or chamber
may be of elliptical form in place of cylindrical, but the cylindrical form
is preferred.
I also place the cleaning doors at the bottom of the furnace, oven, or
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Whitwell in the Great Seal Patent Office*
on the 18th July 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
WHITWELL, of Thornaby Iron Works, Stockton-on-Tees, in the County
of Durham, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of January, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-

page_text: chimney end of the furnace, oven, or heating chamber are by the con-
struction of the walls caused to ascend, then to descend, then to ascend,
and so on, till the heated airs or gases leave the furnace, oven, or heating
chamber at the opposite end of the furnace to that at which they entered.
At the top of each furnace, oven, or heating chamber are iron doors (K, K,)
which arc protected by fire-plugs or lumps L, L, which fit the openings
on the top of the furnace, oven, or heating chamber. These openings on
the top of the furnace, oven, or heating chamber are by preference
formed over the walls which do not come to the top of the furnace, oven,
or heating chamber, by which means the surfaces of the walls situated
below the opening can be cleaned with facility. These openings when
the airs or gases to be heated are passing through the furnace, oven, or
heating chamber are kept closed. In the section shown there are nine
of these transverse walls, but the number and also height of the same
may be varied according to the extent of surface over which it is desired
that the airs or gases to be heated shall pass. At the lower part of the
walls which ascend to the tops of the furnace, oven, or heating chamber
there are openings for the passage of the airs or gases to be heated. Two
or more furnaces, ovens, or heating chambers are used in combination,
in order to maintain a regular stream of heated airs or gases. Gas from
any suitable source is supplied to one furnace, oven, or heating chamber,
whilst the airs or gases to be heated are passing through another furnace,
oven, or heating chamber, and the arrangement of the passages and
valves in connection with the furnaces, ovens, or heating chambers is
such that the airs or gases to be heated pass through the furnace, oven,
or heating chamber in the opposite direction and over the identical
surfaces of the brick walls previously traversed by the burning gases on
heating the furnace, oven, or heating chamber; by these means the airs
or gases to be heated absorb heat from the walls in ascending or
descending, and thus become of the same or nearly the same heat as the
walls of the furnace, oven, or heating chamber, prior to leaving the same.
The dust carried by the burning gas employed in heating the furnace,
oven, or heating chamber accumulates on the walls and requires to be
scraped or removed from time to time. The scraping or removal from
the walls is performed by proper tools introduced through the top
openings K, K, as above described, and the dust is removed from the
bottom of each chamber or oven through the openings closed by the
doors D, D, by means of convenient tools.

page_text: I will now describe the process of the heating of the furnace, oven, or
heating chamber:-The gas from any suitable source is made to enter by
the gas inlet valve B, whence it is conducted to the furnace, oven, or
heating chamber by the pipe C. The hot outlet E is closed, and also the
cold inlet F, whilst the chimney valve G is opened, as also the air inlet
valves H and I for assisting in the combustion of the burning gas; by
this means the walls of the furnace, oven, or heating chamber are made
red hot to a proper proportion of the whole furnace, oven, or heating
chamber, during which time the airs or gases to be heated have been
traversing other furnaces, ovens, or heating chambers, heated previously
in a similar manner. The air admitted at H and I for assisting in the
combustion of the burning gas is conducted to and fro by long air
passages M, N, formed in the thickness of the vertical walls in such way
that the air becomes red hot before it meets the burning gas, and hence
the combustion is made more intense.
I will now describe the heating of the airs or gases: -The furnace,
oven, or heating chamber having been made red hot, as above described,
the burning gas inlet B is closed, as also the air inlets H and I; the
chimney valve G is also closed. Tho hot outlet E which is lined with
refractory material is now opened, also the cold inlet F, by which means
the airs or gases to be heated are made to enter the furnace, oven, or
heating chamber at the coldest end, and by the construction of the
furnace, oven, or heating chamber the airs or gases to be heated ascend
and descend the walls in rotation till they attain to the required tcm-
perature and issue from the furnace, oven, or heating chamber by means
of the hot outlet E. After a proper interval of time, that is to say, before
the airs or gases to be heated cease to be sufficiently heated, they are
shut off from the furnace, oven, or heating chamber, and made to pass
through another similar furnace, oven, or heating chamber previously
heated, by which means a constant current of heated airs or gases is
maintained.
Figure 1, Sheet 3, is a vertical section, and Figure 2, Sheet 3, is a
sectional plan of a furnace, oven, or heating chamber, differing from that
shown on Sheet 2 in that in place of the cleaning openings and doors D
at the lower part of the side openings and doors D' at the bottom of the
furnace, oven, or heating chamber are employed, in which case passages
are provided beneath the structure. The construction of such of the

page_text: valves as are exposed to a high heat is such as is described in the Specifi-
cation of a former Patent granted to me, and dated the 8th day of July,
1871, No. 1797.
Having thus described the nature of my Invention, I would have it
understood that I claim the construction of furnaces, ovens, or heating
chambers for heating airs or gases of a circular or elliptical form, and
with upright walls or partitions stayed by cross walls, and with
openings capable of being closed by means of plugs and doors or valves
for the purpose of cleansing the interior of such furnaces, ovens, or
heating chambers from dust, substantially as described.
I also claim the admission of heated air, substantially as described, for
the combustion of gas in the furnace, oven, or heating chamber.
I also claim the construction of furnaces, ovens, or heating chambers
for heating airs or gases, with, cleaning openings in the bottom, in the
manner substantially as shewn on Sheet 3 of the Drawings.
In witness whereof, I, the said Thomas Whitwell, have hereunto
set my hand and seal, this Sixth day of July, in the year of
our Lord One thousand eight hundred and seventy-two.