IMPROVEMENTS IN THE CONSTRUCTION OF AIR FURNACES FOR THE FUSION OF STEEL AND OTHER METALS, AND FOR ECONOMISING FUEL
Year: 1853

page_text: PROVISIONAL SPECIFICATION left by George Holworthy Palmer
at the Office of the Commissioners of Patents, with his Petition,
on the 26th October 1853.
I, GEORGE HOLWORTHY PALMER, of Sheffield, in the County of York,
Civil Engineer, do hereby declare the nature of the said Invention for.
"IMPROVEMENTS IN THE CONSTRUCTION OF AIR FURNACES FOR THE FUSION
OF STEEL AND OTHER METALS, AND FOR ECONOMISING FUEL," to be as
follows:-
The improvements in the construction of air furnaces are shewn in
the Drawings. hereunto annexed; the principal, object of these improved
furnaces being the employment of carbonic oxide in the fusion of metals.
The Invention is based upon a former Patent granted to William Boggett
and myself, the Twenty-second day of October 1851.
DESCRIPTION OF THE DRAWINGS..
Sheet No 1. Figure 1, sectional plan on the line A, B, Figure 2.
Figure 2, vertical section at the level C, D, Figure 1.
Figure 3, plan of furnace, and bearing bars, and ash
pit on the lines C, D, on Figures 2 and 4.
Figure 4, part section and part elevation taken from
E to F, on Figure 1.

page_text: Sheet No 2, Figure 5, sectional plan, being a modification of
furnace Figure 1, on the line G, HI, on vertical
section Figure 6.
Figure 6, vertical section of furnace from M to M
on Figure 5.
Figure 7, another modification of sectional plan
Figure 1, having two furnaces from N to N on
Figure 8.
Figure 8, vertical section from J to K on Figure 7.
Figure 9, sectional plan of three combined furnaces
at the level of L, L, at Figure 10.
Figure 10, vertical section of the furnaces from C to
D on Figure 9.
The initial letters refer to and indicate the same parts in each and
all of the diagrams on Sheets No 1 and 2, and may be thus further
described :—a, a, interior of the furnaces; b, b, the furnace and bearing
bars; c, c, the furnace ash-pit; d, d, neck of furnace; e, e, the chambers
containing the crucibles in which the metal is fused; 9, g, fire bricks
for regulating the draught through the radial flues f. f, and thereby
ensuring an equalization of caloric to each and all of the said crucibles;
h, h, are openings through which the products of combustion escape
from the furnnaces a, a, into the crucible chambers e, e; j,j, are conical
plugs for the purpose of supplying atmospheric air to the furnaces a, a,
above the incandescent fuel, or into the crucible chambers e, e, in
regulated volumes, in order to ignite the carbonic oxide produced from
the carbonic acid gas generated by the combustion of the carbonaceous
fuel employed, as hereafter more fully explained; k, k, are the crucibles
or melting pots; l, l, the channels through which the volumes of atmo-
spheric air enter to inflame the said carbonic oxide, and also to enable
the melter to inspect and ascertain whether combustion of the said
gaseous oxide of carbon is properly proceeding or otherwise, by removal
of the plugs j, j. The plugs m, m, in Figure 8, offer the means of
inspecting the state of the fuel contained in the hopper passages 8, s.
n, n, are tiles on which the crucibles stand or are supported, as shewn
in Figures 9 and 10. The crucibles in the outside furnaces Nos 1 and 3,

page_text: are partly let into and suspended by the tiles n, n, and project into the
furnaces, as may those in Figures 5, 6, 7, and 8, and also Figures 1
and 2, by carrying the furnace up square if a more rapid and intense
calorific action is required. o, o, lumps for enclosing the entrance to
the chambers e, e, which may be either conical or otherwise, as seen at
Figures 2 and 4 and 10, and are intended for the introduction or removal
of the crucibles, and may be removed and replaced by hand or by the
chain and counterweight suspended over a pulley. These lumps 0, 0,
(at Figures 2, 4, 6, and 10,) are made available for supplying fuel to
the furnaces a, a. p, p, are the exit flues that convey the products of
combustion into the atmosphere either by one chimney shaft or by a
separate exit flue to each furnace, as now adopted. 7, 7, are descend-
ing flues at Figures 5, 6, 7, and 8, and are preferable to rising flues,
inasmuch as the former will ensure the atmospheric air absorbing a
considerable proportion of the waste radial heat in its passage to and
before entering between the furnace bars and combining with the
incandescent fuel. The hopper passages s, s, (before referred to) supply
fuel to the furnaces of Figures 7 & 8, as they do not permit of
being supplied through a central entrance as o, o, as in the furnaces
referred to.
Figures 9 and 10, are arranged upon a principle calculated to
ensure a large saving of the waste heat that would otherwise escape
into the atmosphere, and is accomplished by the auxiliary flues t, l,t,
instead of permitting the products of combustion to escape direct from
each furnace into the flues u, u, u, (now in use) for the conversion of
bar into cast steel. The course taken by the waste heat from cach
furnace, namely, No 1, 2, and 3, as shewn in Figures 9 and 10, may be
thus explained, previously premising that the flues t, t, t, and u, u, u, are
each furnished with a fire brick damper that the products of combustion
may flow through either, as circumstances may dictate. Now assuming
that the passages of the flues u, u, u, (connected with furnaces No 1
and 2,) are closed, and u, u, u, of No 3 furnace, and those of t, t, t, all
open, in this case the waste heat escaping from No 1 furnace will pass
into No 2, where with the heat generated by the combustion of the fuel
in the furnace will, thus combined, act with increased calorific influence

page_text: upon the crucibles in N° 2 furnace, from whence the surplus or waste
heat will pass unto N° 3 furnace, when the same operations and like
results will be obtained. 'Great as will be the advantages consequent
on the use of the waste heat as aforesaid, nevertheless a further
economy of fuel will be ensured by continuing the flues t, t, t, down-
ward, as indicated by the dotted lines r, r, and which are connected to
the furnaces No 2 and 3, about 2 feet above, the level of the furnace
bars. By this further improvement the exit flues t, t, t, connected with
the furnaces as aforesaid, will be abandoned, and the waste lient,
together with the carbonic acid formed by the combustion of the
carbonic oxide in No 1 furnace, will pass into N° 2 furiace, through
the exit fluct, t,, (as thus modified,) and the non-inflammable gas
(carbonic acid) will, in its passage through the superincumbent ignited
fuel, be a second time reconverted into an inflammable gas, carbonic
oxide, and will, by its ignition, give out a large extra amount of sensible
caloric to the crucibles, and again be converted by its combustion into
carbonic acid gas. The same advantageous operations will be repeated
in N° 3 furnace as in N° 2, when all the products of combustion of
the said furnaces will finally escape from N° 3 furnace into the exit
flue .
The combining of distinct furnaces, as carried out in
Figures 9 & 10, will be applied to all the other modifications before
explained should the manufacturer's business be such as to require
inore than one furnace containing any number of crucibles not exceeding
from 15 to 20 crucibles each. Although I have described only three
furnaces thus combined this number may be increased, but not with a
corresponding amount of advantage, as the flues t, t, t, would become
inconveniently large for conveying the great accumulation of gascous
products, particularly the nitrogen gas liberated by the decomposition
of the atmospheric air required for igniting the solid carbonaceous fuel
and its auxiliary carbonic oxide. v, v, v, in Figures 1, 2, and 4, is a
flue of large dimensions, connected with and receiving the gaseous
products escaping from the radial flues f,f,f, and is intended to equalize
the draught upon the said radial flues, but which will be far better
accomplished by the adoption of the aforesaid regulating draught
bricks g, g, in Figures 1, 2, & 4, and substituting the smaller descending

page_text: flues
before referred to, for the flue v, v, v. The openings w, w, as
shewn by the ilotteil lines as seen in Figures 1, 2, 3, 4, and 6,' are for
the removal of any solid depositions within the flues v, v,.v, or q, q,
aforesaid. a,, are openings under the bottoms of the crucibles in
Figures 1, 2, 4, 6, 8, & 10, and will absorb a portion of the heat in its
passage from the furnaces a, a; into the chambers e,. e. The caloric
evolved by the combustion of the fuel is of two distinct characters:;
first, that generated by the combustion of the solid carbonaceous fuel;
and, secondly, by the ignition of the gascous oxide of carbon.produced,
as heretofore explained, by the carbonic acid taking up a further dose
of gascous carbon in its passage" over the incandescent fuel. Here,
then, we arrive at the very important double fact, that of a non-
inflammable gas becoming inflammable, and of its applicability, as an
auxiliary fuel, for heating the crucibles and thereby economizing the
expenditure of the carbonaceous fuel-now-employed for fusing, and if
previously ignited by the waste heat will ensure the maximum amount
of carbonic acid being converted into an inflammable oxide. The
altitude of the incandescent fuel required to decompose the whole of the
atmospheric air entering between the furnace bars and at the
opening z, z, (which offers the further convenience of adjusting and
removing any of the furnace bars) will be most effectively performed by
5 feet in the furnaces Nos 1, 2, & 3; and even in Figures 9 and 10,
where a greater height is required in order to ensure the carbonic acid
(generated by the combustion of the carbonic oxide in another furnace)
being reconverted again into an inflammable gas as aforesaid. Revert-
ing again to the central opening 0, 0, through which an assumed
maximum number of crucibles can be introduced and removed from
the chamber in which they are heated, and in order to extend this
important principle to any number of crucibles, I accomplish this
desideratum as follows:-To and above the concentric crucible
chamber will be fitted a fire brick or stone cover, enclosed and secured
within a suitable cast iron frame, which cover will be readily made to
revolve upon a centre pivot by the application of radial lever arms, as
it will be furnished with and travel upon small metal rollers. In this
revolving cover there will be an opening fitted with a lump o, o, similar

page_text: to those attached to the furnaces before described, which (as the
crucibles k, k, are arranged in a circular form) will in its rotation pass
immediately over each crucible in succession, and thereby readily admit
of their being introduced or removed from the chamber. For the
regulation of the admission of atmospheric air into the furnaces for the
combustion of the solid carbonaceous fuel a damper will (as in the
usual way) be applied either to a closed ash-pit or to the exit flue of
each furnace.
I do not confine myself to all the details in the Drawings and
description, but I claim the right to vary and modify them so long as
the main features of my arrangements are adhered to.