IMPROVEMENTS IN FURNACES SUITABLE FOR MELTING AND HEATING METALS, AND FOR OTHER PURPOSES
Year: 1870

page_text: LETTERS PATENT to Thomas Russell Crampton, of Great George
Street; Westminster, in the County of Middlesex, for the Invention
of "IMPROVEMENTS IN FURNACES SUITABLE FOR MELTING AND HEATING
METALS, AND FOR OTHER PURPOSES.”
Sealed the 7th March 1871, and dated the 30th September 1870.}
PROVISIONAL SPECIFICATION left by the said Thomas Russell
Crampton at the Office of the Commissioners of Patents, with his
Petition, on the 30th September 1870.
i
I, THOMAS RUSSELL CRAMPTON, of Great George Street, Westminster,
in the County of Middlesex, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN FURNACES SUITABLE FOR MELTING AND
HEATING METALS, AND FOR OTHER PURPOSES," to be as follows :-
According to this Invention I construct furnaces of a circular or
equivalent form, and so that they may be heated by an admixture

page_text: of air and powdered fuel injected in one or more streams into the
central part of the furnace. The material to be heated, whether in pots,
retorts, or in an open bath or bed, or otherwise, is placed all around the
central space. The products of combustion pass laterally in all directions
from the central space to openings or flues situated at or near the sides
of the furnace heating the material under treatment in their passage.
I prefer to construct the furnace as follows:-The bottom of the
furnace is composed of metal plates covered with refractory material,
the outer edge of the bottom plates rest on isolated piers of brickwork,
the centre and other portions of the plate also rest on brickwork or
other support. The roof of the furnace is composed of a dome of brick-
work built in a ring of metal. The ring is carried by supports placed
at intervals around it and resting upon the bottom plate. The space
between the ring and bottom plate is closed by a series of doors arranged
to be readily opened and closed. Openings may also be formed for
introducing the ends of bars to be heated. A number of streams of air
and powdered fuel are introduced through the roof in a direction
inclining downwards and radially towards the centre. The outlet
openings to the exit flue are formed through the bottom plate near to its
outer extremities.
Also, according to my Invention, I construct furnaces suitable for
melting or heating metals and other substances of a cylindrical or conical
form open at the top. The material to be heated is placed at the bottom
of the furnace, and powdered fuel and air are injected downwards into
the furnace through a suitable jet or jets at such a height from the
material under treatment at the bottom of the furnace that the fuel is
sufficiently consumed before reaching the material. The products of
combustion, or the greater part of them, pass to or near to the bottom
of the furnace and return upwards and pass away from the furnace at
its upper end. Suitable openings for charging, working, and drawing
out the material are made in the sides or bottom of the furnace.
prefer to construct the furnace of a cylindrical casing of iron, closed at
the bottom and lined internally at the sides and bottom with fire-brick,
ganister, or other refractory material.
I

page_text: SPECIFICATION in pursuance of tlie conditions of the Letters Patent,
filed by the said Thomas Russell Crampton in the Great Seal Patent
Office on the 30th March 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
RUSSELL CRAMPTON,. of Great George Street, Westminster, in the County
of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of September, in the year
of our Lord One thousand eight lundred and seventy, in the thirty-fourth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Thomas Russell Crampton, Her special license,
that I, the said Thomas Russell Crampton, my executors, administrators,
and assigns, or such others as I, the said Thomas Russell Crampton; my
executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
FURNACES SUITABLE FOR MELTING AND HEATING METALS AND FOR OTHER PURPOSES,"
upon the condition (amongst others) that I, the said Thomas Russell
Crampton, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Russell Crampton, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by
the following statement thereof, that is to say: --
According to this Invention I construct furnaces of a circular or
equivalent form (say, for example, polygonal) and so that they may be
heated by an admixture of air and powdered fuel injected in one or more
streams into the central part of the furnace. The material to be heated,
whether in pots, retorts, or in an open bath or bed, or otherwise, is
placed all around the central space. The products of combustion pass
laterally in all directions from the central space to openings or flues

page_text: situated at or near the sides of the furnace heating the material under
treatment in their passage.
A furnace constructed in the manner I prefer is shewn at Figures 1
and 2 of the Drawings annexed.
Figure 1 is a section of the furnace through the line A, B, in Figure 2;
Figure 2 is a section through the line C, D, in Figure 1. The letters in
each Figure denote the same parts. The bottom of the furnace is com-
posed of metal plates a, a, covered with refractory material b, the outer
edges of the bottom plates rest on isolated piers of brickwork c, c, the
centre and other portions of the plate also rest on brickwork or other
support. The roof of the furnace e is composed of a dome of brickwork
built in a ring of metal f, the ring is carried by supports g, g, placed at
intervals around it and resting upon the bottom plate a.
The space
between the ring and bottom plate is closed by a door or series of doors,
through which the material to be treated is inserted into the furnace
and arranged to be readily opened in any ordinary manner. Openings
may also be formed at any convenient point of the furnace for intro-
ducing the ends of bars to be heated. A number of streams i, i, i, i, i,
of air and powdered fuel are introduced by the means of pipes and by
preference through the roof in a direction inclining downwards and
radially towards the centre. The outlet openings j,j, to the exit flue k, k,
are formed through the bottom plate near to its outer extremities,
through which the products of combustion pass to the chimney. Air
and powdered fuel may be supplied to the inlets i as described in the
Specification of a Patent granted to me, dated December Third, One
thousand eight hundred and sixty-nine, No. 3504. The furnace may
also be heated at starting as described in the same Specification.
The mode of working is as follows:-The furnace being heated to the
required temperature the material, say, steel, to be treated being in
pots 1, 1, the pots are inserted through the doors h, h, in the position
shewn (or practically so) in Figures 1 and 2, and are heated by the
heat produced in the central part of the furnace, the products passing
above and between the pots down the openings j, j, to the flues k, k, and
thence to the chimney. In the event of its being required to melt iron
or steel in a bath, an annular or other form of bath or baths is constructed
of suitable material in the usual manner in the space shewn occupied by
the pots, into which through proper openings or doors the material
is placed. Proper apertures for the removal of the material when

page_text: sufficiently heated or melted are also to be constructed at one or more
convenient parts of the furnace. Any slag which accumulates during
the operation may be allowed to run out of suitable openings arranged
for the purpose, or it may be otherwise removed by any of the ordinary
well-known means.
What I claim as regards this part of my Invention is,―
1. The use of furnaces constructed of a circular or equivalent form,
and so that they may be heated by an admixture of air and powdered
fuel injected in one or more streams into the central portion of the
furnace whilst the products of combustion escape through openings at
or near the sides, substantially as herein-before described.
2. The use of furnaces constructed substantially as herein-before
described and heated by an admixture of air and powdered fuel injected
in one or more streams into the central portion of the furnace.
Also according to my Invention I construct furnaces suitable for
melting or heating metals and other substances of a cylindrical or
conical form open at the top. The material to be heated is placed at
the bottom of the furnace and powdered fuel and air are injected down-
wards into the furnace through a suitable jet or jets at such a height
from the material under treatment at the bottom of the furnace that
the fuel is sufficiently consumed before reaching the material. The
products of combustion or the greater part of them pass to or near to
the bottom of the furnace and return upwards and pass away from the
furnace at its upper end. Suitable openings for charging, working, and
drawing out the material are made in the sides or bottom of the furnace.
I prefer to construct the furnace of a cylindrical casing of iron closed at
the bottom and lined internally at the sides and bottom with fire-brick,
ganister, or other suitable refractory material.
A furnace constructed in the manner I prefer for carrying out this
part of my Invention is shewn at Figures 3 and 4.
Figure 3 is a section through the line C, D, in Figure 4, and Figure 4
is a section through the line A, B, in Figure 3. The letters in each
Figure denote the same parts. The furnace shewn in these Figures is
suitable for melting steel or other metal. It is constructed of fire-brick
or other refractory material and is of a cylindrical form similar to an
ordinary cupola for melting iron. a is a bath formed in the usual
manner for such purposes; b a door or inlet for inserting into the

page_text: furnace the material to be heated. This inlet is shewn near the bottom,
but may be made at any convenient height from it, and more than one
may be used.
c is an outlet for draining off the melted materials when
required. d, d, d, d, are inlet pipes passing through water tuyeres or
through the brickwork for carrying the air and powdered fuel into the
furnace by preference in an inclined direction to each other. The inlet
pipes are situated at such a height above the bottom that the mixture
may be sufficiently consumed before reaching the material under treat-
ment at the bottom a, say at a height of ten or twelve feet, the distance
will however depend upon the dimensions of the fuel used.
It is not essential to have any particular form of furnace if the main
features are adhered to of injecting downwards into the furnace, whilst
the products return upwards through it.
If the material under treatment would not be injured by the fuel not
being all consumed the fuel and air may be introduced at a less height
from the bottom of the furnace than would otherwise be necessary.
The furnace will have to be heated in the first instance as previously
mentioned and described in my previous Patent before alluded to.
At Figures 5 & 6 are shewn modified forms of the furnace above
described.
What I claim as regards this part of my Invention is, the use of
furnaces constructed so that the materials to be melted or otherwise
treated are placed at the bottom of the furnace, and are heated by
atmospheric air mixed with powdered fuel projected downwards into the
furnace whilst the products of combustion return upwards through
the furnace, substantially as herein-before described.
In witness whereof, I, the said Thomas Russell Crampton, have
hereunto set my hand and seal, this Thirtieth day of March, in
the year of our Lord One thousand eight hundred and seventy-
one.