IMPROVEMENTS IN MEANS AND APPARATUS FOR HEATING, SMELTING, AND WORKING METALS, AND IN FURNACES EMPLOYED THEREIN, WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO HEATING AND OTHERWISE OPERATING UPON MINERALS AND OTHER SUBSTANCES
Year: 1869

page_text: LETTERS PATENT to Edward Dorsett, of London Street, in the City
of London, for the Invention of "IMPROVEMENTS IN MEANS AND
APPARATUS FOR HEATING, SMELTING, AND WORKING METALS, AND IN
FURNACES EMPLOYED THEREIN, WHICH IMPROVEMENTS ARE ALSO APPLICABLE
TO HEATING AND OTHERWISE OPERATING UPON MINERALS AND OTHER
SUBSTANCES."
Sealed the 13th August 1869, and dated the 19th February 1869.
PROVISIONAL SPECIFICATION left by the said Edward Dorsett at
the Office of the Commissioners of Patents, with his Petition, on
the 19th February 1869.
I, EDWARD DORSETT, of London Street, in the City of London, do
hereby declare the nature of the said Invention for "IMPROVEMENTS
MEANS AND APPARATUS FOR HEATING, SMELTING, AND WORKING METALS, AND IN
FURNACES EMPLOYED THEREIN, WHICH IMPROVEMENTS ARE ALSO APPLICABLE
HEATING AND OTHERWISE OPERATING UPON MINERALS AND OTHER SUBSTANCES," to
be as follows:-
ΤΟ

page_text: for the purpose of producing an intense heat in furnaces, chambers,
or kilns used for heating, smelting, or working metals and other
substances.
In carrying out my Invention I first evaporate and distribute in the
vaporized state under pressure (as described in a Patent granted to me
en the 18th January 1868, No. 176) the said liquid hydrocarbons through
a pipe or series of pipes from which the said vapour issues in the form
of jets. As this vapour escapes from the holes in the pipes it mixes
with the air necessary for its combustion, the air being previously heated
if required. The hydrocarbon vapour thus mixed with air (or in some
cases with steam or other gases) enters the chamber or furnace through
an opening or openings formed therein wherever it may be found most
convenient. Such openings should be provided with doors or other
means of regulating the quantity of air or gas, required to feed the flame
or to modify its action upon the metal placed in the furnace to be heated,
melted, or converted, as the case may be. The jets of flame may be
regulated so as to completely fill the furnace or other chamber, or can
be directed so as to impinge upon the object or substance to be heated
therein. This system of heating can be adapted to furnaces of any kind
without any alteration whatever in their construction. The pipe sup-
plying the vapour may be made to distribute its flame from or above
the fire bridge, and the furnace will be at once capable of producing a
much more intense heat than is possible to obtain with coal, and the
heat can be modified at will or entirely suspended at intervals by the
turning of the cock or stopper connected with the pipe leading from the
generator to each or any furnace.
It is evident that for melting pot furnaces used by founders, steel
makers, glass workers, and others this system possesses great advan-
tages.
In my system of heating furnaces the fire chamber, fire bars, and
bridge used in the ordinary coal-burning furnaces are not required. The
furnace I prefer, and which I call "The Dorsett Hydrocarbon Furnace,"
consists of a chamber in which the hydrocarbon vapour produced by a
separate generator is distributed, as described in my Patent of the 18th
January 1868 before mentioned, and is made to enter the chamber or
furnace through an opening or openings in any convenient part thereof,
and in such quantity as may be found necessary to heat, work, or convert
the plate, forging, or other object or substance placed in the said furnace

page_text: or chamber, the fire grate, bars, furnace, and bridge being entirely dis-
pensed with.
This Invention is also applicable to the heating of all kinds of rever-
beratory furnaces used for the purposes of puddling, melting, or con-
verting all kinds of metals, and heating and otherwise operating upon
minerals and other substances.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Dorsett in the Great Seal Patent Office on
the 13th August 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
DORSETT, of London Street, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of February, in the year
of our Lord One thousand eight hundred and sixty-nine, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Edward Dorsett, Her special
licence that I the said Edward Dorsett, my executors, administra-
tors, and assigns, or such others, as I, the said Edward Dorsett, 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
MEANS AND APPARATUS FOR HEATING, SMELTING, AND WORKING METALS, AND IN
FURNACES EMPLOYED THEREIN, WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO
HEATING AND OTHERWISE OPERATING UPON MINERALS AND OTHER SUBSTANCES,"
upon the condition (amongst others) that I, the said Edward Dorsett,
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.

page_text: NOW KNOW YE, that I, the said Edward Dorsett, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement and accompanying two Sheets of Drawings
(that is to say):-
This Invention consists in the employment of liquid hydrocarbons for
the purpose of producing an intense heat in furnaces, chambers, or
kilns used for heating, smelting, or working metals and other
substances.
In carrying out my Invention I first evaporate and distribute in the
vapourized state under pressure (as described in a Patent granted to me
on the Eighteenth January One thousand eight hundred and sixty-
eight, No. 176) the said liquid hydrocarbons through a pipe or series of
pipes from which the said vapour issues in the form of jets. As this
vapour escapes from the holes in the pipe it mixes with the air neces-
sary for its combustion (the air being previously heated if required), and
the lydrocarbon vapour thus mixed with air (or in some cases with
steam or other gases) enters the chamber or furnace through an opening
or openings formed therein wherever it may be found most convenient,
such openings being provided with doors or other means of regulating
the quantity of air or gas required to feed the flame or to modify its
action upon the metal placed in the furnace to be heated, melted, or
converted, as the case may be. The jets of flame may be regulated so
as to completely fill the furnace or other chamber, or they may be
directed so as to impinge upon the object or substance to be heated
therein. This system of heating can be adapted to furnaces of any
kind without any alteration whatever in their construction. The pipe
supplying the vapour may be made to distribute its flame from or above
the fire bridge, and a much more intense heat will be produced in the
furnace than is possible to obtain with coal, the heat being modified at
will or entirely suspended at intervals by the turning of a cock or
stopper connected with the pipe leading from the generator to each or
any furnace.
It is evident that for melting pot furnaces used by founders, steel
makers, and others this system possesses great advantages.
In my system of heating furnaces the fire chamber, fire bars, and
bridge used in the ordinary coal-burning furnace are not required. The
furnace I prefer to use, and which I call the Dorsett Hydrocarbon
Furnace," consists of a chamber in which the hydrocarbon vapour pro-

page_text: duced by a separate generator is distributed, as described in my Patent
of the Eighteenth January One thousand eight hundred and sixty-eight
before mentioned, and is made to enter the chamber or furnace through an
opening or openings in any convenient part thereof, and in such quantity.
as may be found necessary to heat, work, or convert the plate, forging,
or other object or substance placed in the said furnace or chamber.
This Invention is also applicable to the heating of all kinds of rever-
beratory furnaces used for the purpose of puddling, melting, or con-
verting all kinds of metals, and heating and operating upon minerals and
other substances.
I have described in my previous Patent of Eighteenth January One
thousand eight hundred and sixty-eight, No. 176, the method I employ
for heating furnaces by burning creosote or other liquid hydrocarbons
in the vapourized state, the said hydrocarbons being forced in by
their own pressure, and as the effects produced from hydrocarbons in
generating heat for smelting and working metals in furnaces and as
carburizing agents have long since been known as scientific facts, it will
be sufficient for me to set out my methods of employing my said pro-
cess to furnaces used in metallurgical operations generally, and more
particularly to melting pot furnaces and other furnaces used in the
melting of steel and malleable wrought iron.
And in order that my said Invention may be more fully understood [
will now describe the methods I am acquainted with for applying the
said Invention to furnaces for heating, smelting, and converting metals
and metallic ores.
Plate 1 represents a reheating furnace arranged according to my.
Invention. Fig. 1 is a longitudinal section through the line 1, 2, of
Figs. 3 and 4; Fig. 2 is a plan over the arched roof; Fig. 3 is a horizontal
section through the line 3, 4, of the Figs. 1 and 4; Fig. 4 is a cross
section through the line 5, 6, of the Figs. 1 and 2; Fig. 5 shows in plan
the system of distributing and regulating the air supply and mixing it
with the hydrocarbon vapour; Fig. 6 is a vertical section through the
line 7, 8, of the Fig. 5.
As will be seen by the Drawings the furnace consists of a heating
chamber A constructed in the usual manner, except that the fire place
and bridge used in ordinary furnaces are removed. This chamber is
divided by the hearth B from other chambers F, F', formed for the

page_text: purpose of heating the air where it may be desirable, as will be after-
wards described; the hearth or furnace bottom B is formed as may be
necessary for the purpose for which the furnace is required. The lower
chambers F and F' receive through the openings G the products of the
combustion from the furnace A, which said products are employed to
heat air passing through pipes or channels b, b, and b', b'. These pipes
or channels are united at one end by a return box H; the other end of
the said pipes terminate in the chambers F, F', arranged so as to
command the entrance of the cold air by the one chamber and the
delivery of the heated air by the other. A current of air (compressed
by any known means if necessary) enters the pipes or channels b, b, in
the chamber F, and passes by the pipes or channels b', 6', in the
chamber F into the pipes J and K, on which are the branches L
terminating in valves M, shown in detail in Figures 5 and 6. (This
valve is shown as a convenient means of regulating the quantity of air
and bringing it into intimate contact with the vapour to be burned in
the furnace, but many other means of effecting the same object may be
employed.
The valve, Figs. 5 and 6, consists of two casings d and a bolted
together, and between them a loose plate with a hole in the centre is
held in place by the bolts of the two casings, the whole forming a top
and bottom chamber, the top chamber in connection with the air tube
L, the bottom one discharging itself into the furnace by the nozzel m
(this nozzel should be of fire-clay reaching through the crown of the
furnace, but an opening in the crown may be made to answer the same
purpose. The bottom chamber d' receives the vapour pipe N, which
branches off from its main supply pipe P and is stopped or regulated as
required by valves, the vapour (under pressure) in the pipe N being
admitted as required. The air in the pipe J rushing into the chamber d,
either by the force of its own expansion, aided by the induced current
formed by the jet of vapour passing through the hole a (or if necessary
forced in by any known means), is admitted into the chamber d' by the
valve moved by the screw ; from this chamber it is drawn into the
furnace with the jet of vapour a and is ignited by the heat that it there
encounters, while at the same time it is forced by its own pressure upon
the metal or mineral placed in the furnace to be heated or melted.
These tuyèyes or nozzels m may be placed in any part of a furnace or
chamber and in any number required. In the Drawing six nozzels are

page_text: shewn distributed from the crown of the furnace, each separate nozzle
forming a separate high-pressure blow pipe that may be made to heat,
at the discretion of the operator, the whole or any part of the surface
of the metal or other matter placed in the furnace with an intensity of
heating power or with a carburetting or oxidizing effect which is regu-
lated by the air valve M and the vapour valve.
The holes G for the escape of the gases of combustion are distributed
over the furnace bottom so as to equalize as much as possible the action
of the combustible used. This is particularly applicable to reheating
furnaces. It is obvious that for smelting, puddling, and other furnaces
the position and quantity of these escape holes may be modified as
'occasion may require. The chambers F, F', also are placed in the
Drawing to show a means of economizing the combustible by heating the.
air, but in furnaces where this is not considered necessary valves or
shutters opening to the air and to the furnace, as shown in the descrip-
tion of the valve M, will answer the purpose, but with a greater con-
sumption of hydrocarbon than if the air was employed to absorb the heat
escaping with the combustion gases.
I also apply the carburizing effect of hydrocarbon vapour to the
conversion of bar iron into steel, and to forming upon articles of iron
a steel surface by exposing the bars of iron, forgings, or plate to the
action of carbonic oxide gas formed by the slow combustion of hydro-
carbon vapour.
In the conversion of bar iron into steel I employ
rectangular chambers or cases of refractory materials (such as are
ordinarily employed), in which the bars of iron are piled layer upon
layer so as to expose all their surfaces to the action of the carbonic oxide
gas. The chamber is constructed so as to allow the top to be closed to
exclude the external air. Openings for the escape of a part of the com-
bustion gases are formed in any convenient part of the chamber, and
these openings are to be closed as required by dampers. A certain
number of tuyères for the admission of the hydrocarbon vapour (under
pressure mixed with the necessary quantity of air as already described)
are placed so as to discharge the vapour and air into the case. The
bars of iron are placed in the chamber or case and brought to the degree
of heat required by the action of the tuyères, the holes for the escape of
the combustion gases being opened as much as is necessary to maintain
an active combustion. In a short time the interior of the chamber and
the bars placed therein will have attained the degree of heat favorable to

page_text: the absorption of the carbonic oxide gas; the draught openings are then
almost entirely closed, and the air supply is limited so as to maintain in
the chamber an atmosphere charged with carbonic oxide, which is
continued as long as may be found necessary. A little pressure can be
maintained in the furnace, and a small jet or jets of the furnace gases
can be burned outside or can be otherwise tested as found necessary; thus
the degree of carburization can always be seen by the workmen in charge.
The admission of hydrocarbon vapour and air and the exit of the gases
can be regulated as required so as to maintain the heat necessary with
the degree of carburization favorable to the conversion of the bars in the
case or chamber into steel.
Plate 2, Figs. 1, 2, and 3, shows the method of applying my system of
heating by the combustion of liquid hydrocarbons vapourized under
pressure to melting pot furnaces used by steel makers, founders, and
others. Fig. 1 is a longitudinal section of a furnace containing 6 melt-
ing pots through the lines 5, 6, of Fig. 2 and 3; Fig. 2 is a cross section
on the line 1, 2, of Fig. 1; Fig. 3 is a cross section through the line 3, 4,
of Fig. 1.
The heating chamber or furnace M is constructed according to the
size and number of melting pots required to be heated. The bottom of
the furnace is solid or arched, or as shewn in the Drawings, with parts
clevated on which the melting pots are placed, and between these are
beds of ashes or other matter to receive any metal that may run out of
the pots through leakage or accident.
In
The general construction of melting pot furnaces is well known.
the Drawing B, B, represents the top of the furnace with its plate or
cover for introducing or lifting out the melting pots. The melting
pots A are placed in an inclined position so as to allow the jets of flame
to play directly upon the metal in the pots. The shape of the cheeses F
on which the pot rests and that of its fire-brick supports C will depend
upon the degree of inclination to be given to the melting pot in case it is
desired to act directly upon the metal it contains, or if covers are used as
at present in the melting of steel, malleable cast iron, &c., and the pot
placed upright, then the position of the tuyere may be changed as desired
and made to impinge upon any part of the furnace that may be found a
most convenient. In the Drawing P shows the vapour pipe, H the air
pipe, E the tuyere entering the furnace. The air passages H' are fitted

page_text: with regulating valves or cocks I. The pipe R which supplies the hydro-
carbon is fitted with valves or cocks J to each branch pipe P.
In the Drawing a longitudinal form of furnace is shown for the sake
of clearness, but I consider the circular form which I shall now proceed
to describe as preferable in many respects.
Figs. 4 and 5 represent an improved form of furnace in which melting
pots are not required. Fig. 4 represents on the left hand a plan of a
melting furnace, the right hand of the same Figure being a section of
the same through the line 1, 2, 3, 4, of Fig. 5; Fig. 5 is a cross section
through the line 5, 6, of Fig. 4.
This furnace consists of a circular block of refractory material A
(encased as is usual in iron) in which are formed the chambers or cupolas
B. These cupolas communicate with each other by the passages G, G',
G2, G3, &c., &c., &c., &c., &c., which permit (the combustion gases to
pass from one cupola to another. D, D', D2, D3, shew passages for the
escape of the combustion gases into the chamber N, where they can be
used for heating the air before being allowed to pass into the chimney
by the flue F, or a part of the gases may be made to pass around and
heat the hydrocarbon generator. Each of the passages G and D, 1 to
9, has its own separate regulator or damper L.
The action of the furnace is as follows:-Each cupola being charged
with the metal to be melted the vapour is turned on (with its air supply)
into the cupola B, for instance. This supply may be brought in at any
part that may be thought necessary, the combustion gases escaping by
the passage G into the cupola B', and after by the passage G' into the
cupola B, then by the passages G and G³ into the cupolas B³ and B',
whence they are allowed to pass into the chimney or air heater by the
passage D'.
When the metal is ready to be run out of the cupola B its
supply of combustible is turned off and its connection with the cupola B¹
is closed by the dampers in the passage G, the combustible being
admitted into the cupola B¹. The melting is continued as before for
each of the cupolas respectively. The metal is run out of the cupola B
into the ingot mould T, the cupola B is then recharged with metal, the
passage G is opened to the cupola B, and its passage D is also opened
into the chamber N; it thus becomes the last of another series of cupolas
discharging into the chamber N the gases that have passed by other
cupolas, and so on alternately. The method of supplying the hydro-

page_text: carbon vapour and air is shewn in detail in the description of Figures
1, 2, and 3.
I have only shewn in the Drawing the general arrangement of furnaces
of this kind, the mode of construction, size, form, and number of melt-
ing chambers will vary with the purposes for which they are required to
be used, and any amount of heat can be concentrated as required upon
every cupola or chamber of the series. As the heat in the furnaces is
caused by the instantaneous change and dilatation that takes place in
the gaseous components of the vapourized combustible which forces itself
at high pressure into the intensely heated furnace chamber mixed with
the air for its combustion, it follows that the furnaces must be con-
structed to resist the continual pressure formed in them, and where a
great concentration of heat is required the openings may be fitted with
doors or covers made to hold a lute as in the case of gas retorts, so as to
prevent the escape of the flame.
The combustion gases in their passage through the several cupolas
may be re-carburized if desired by admitting hydrocarbon vapour through
the tuyeres, and the combination of furnaces can be modified to any
extent by opening or closing dampers in the several cupolas that the
furnace gases are made to pass through. The chamber N can be
arranged to contain pipes or passages for heating the air.
I have confined the description of the furnace, Plate 2, Figs. 1, 2,
and 3, to that of a furnace to be used with melting pots, and the
description of the furnace, Plate 2, Figs. 5 and 6, to that of a furnace to
be used without melting pots, but I can use melting pots either by
confining the gases to separate chambers, as in Figs. 5 and 6, or I can
modify my system of heating for glass house pots and other purposes in
such a manner that the melting pots can either be heated separately or
any number of them together under a muffle or domed roof, where the
melting pots can be placed so as to allow the metal or other substance
melted or fused in them to be withdrawn through openings in the
exterior of the furnace, as is now done in glass houses, or the melted
metal or mineral can be tapped out of the melting pots through an
opening formed for that purpose. In other cases a number of melting
pots can be placed in a chamber (circular by preference, and several
jets of vapour and air (as before described) be made to play into the
chamber from the circumference thereof, the chamber having a move-
able cover which gives access to the melting pots. The draught holes

page_text: are arranged in the bottom or floor of the chamber, either so as to con-
centrate or to disseminate the flame from the different jets. The flame
from each of the blow pipes or jets is directed towards the centre of the
chamber, so that a number of melting pots can be subjected to an
intense heat at the same time. The pressure in the vapour generators
may vary from a few pounds to several atmospheres on the square inch;
this pressure causes the pressure on the blow pipe jets, which conse-
quently varies with it. The vapour generators can be made of any
desired form, and can be heated by the gases from the furnaces; or a
circulation of creosote or other matter capable of supporting a high
temperature with a small proportionate expansion may be made to
circulate through pipes placed in the flues or otherwise so as to take up
the heat from the furnace, which pipes are then made to circulate
through the interior of the vapour generator so as to heat and evaporate
the creosote or other hydrocarbon contained therein and maintain the
pressure required for its distribution. The air required to support the
combustion may be heated by any known means and forced into the
furnaces if necessary, or it may be drawn in by a chimney draught and
the induced current formed by the jets themselves. The arrangements
of the pipes and valves or cocks for regulating the admission of the
hydrocarbon vapour and air may be also varied to suit particular pur-
poses, or other gases may be introduced in combination with them.
Having thus described the nature of my said Invention, and the manner
in which the same is to be practically carried into effect. I claim as
constituting the Invention secured to me by the herein-before in part
recited Letters Patent,―
First. The general arrangement and construction of apparatus herein-
before described, and the application thereof to heating, smelting,
working, and converting iron and other metals, metallic ores, and
other substances in furnaces or chambers in which hydrocarbon
vapour is supplied under pressure, as described in my Patent before
mentioned.
Secondly. The general arrangement and construction of furnaces to
be used with melting pots for melting steel and other metals, metallic
ores, and other substances, in which said furnaces liquid hydrocarbons
are supplied in the vapourized state under pressure, as herein-before
described.
Thirdly. The general arrangement and construction of furnaces to be

page_text: EDWARD DORSETT. (L.S.)