Improvements in or connected with Reverberatory Furnaces..
Year: 1890

page_text: Date of Application, 26th Apr., 1890
Complete Specification Left, 18th Dec., 1890-Accepted, 28th Feb., 1891
PROVISIONAL. SPECIFICATION.
[Communicated from abroad by GoTTFRIED PIETZKA, Engineer, of Witkowitz,
Moravia, in the Austro-Hungarian Empire.]
Improvements in or connected with Reverberatory Furnaces..
We, JOSEPH VON LANGER, Engineer, and LEONARD COOPER, Iron Merchant,
both of 32, Park Row, Leeds, in the County of York, do hereby declare the nature
of this invention to be as follows:-
This invention relates to a furnace which can be turned on its centre, so that
each of its two hearths or ends may be alternately placed nearest to the fire or
source. of heat.
The moveable part of the furnace has at each end an inclined surface, which fits
upon a correspondingly inclined surface formed on the stationary brick work or
base so as to make a joint. One of the said joints is traversed by the inlet for the
heating gases, and the other by the outlet for the waste gases.
For reversing the position of the two hearths, the moveable part is first lifted
vertically, so as to bring the symmetrically inclined surfaces out of contact with
their respective bases, after which the moveable part is turned 180 degrees,
and again lowered, until the inclined surfaces touch their inclined seats, and form
a joint. That opening of the moveable part, which previously was the inlet for the
heating gases now forms the outlet for the waste gases, and fits upon the flue
leading to the chimney or to the regenerator.
To facilitate the lifting, the whole moveable furnace is supported by a plate or
metallic frame which can be raised by a hydraulic cylinder placed underneath the
centre or by other suitable means.
While the front hearth is used for smelting or other operations, for which the
furnace is intended, the rear hearth may serve to heat the raw material for the next
operation, thus saving time and economising heat.
This reverberatory furnace may be heated either directly in the ordinary
way or by means of gas. In the latter case, the gas producers are preferably
placed close to the furnace, in order that the gas may enter the furnace at a high
temperature.
Each of the hearths is provided with a roof of fireproof material, and with sidė
doors as usual.
521
י
"
+
1000
COMPLETE SPECIFICATION.
Improvements in or connected with Reverberatory Furnaces.
We, JOSEPH VON LANGER, Engineer, and LEONARD COOPER, Iron Merchant,
both of 32, Park Row, Leeds, in the County of York, 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 double or two-hearth furnaces applicable for puddling,
heating, calcining, burning, smelting, welding, steel-making and other operations,
for which reverberatory furnaces may be used.
The principal feature of novelty is, that the relative position of the two hearths
or ends can be reversed, by turning the entire furnace sole, together with its

page_text: E is the air inlet to the recuperator.
F is the flue leading the hot air from the recuperator to the furnace.
G is the flue leading from the recuperator to the chimney and H a cylinder
containing a piston for lifting the moveable body of the furnace by hydraulic
pressure.
The furnace chiefly comprises two hearths B, B, which are separated from each
other by a water-cooled partition and, supported by iron girders, M, which, in
their turn, are fixed to the platform of a hydraulic lift H.
The mouth J, for the admission of the heating gases to the furnace and the
opening J, for the discharge of waste gases, are exactly alike, as regards their
sectional area and their distance from the axis of rotation of the furnace (which is
the axis of the lift), and their soles are on the same level.
The moveable furnace is limited by inclined faces K, K2, which form part of an
inverted cone having its apex in the axis of rotation of the furnace.
b₁, and b₂ are the water-cooled end walls of the hearths, b, b, the usual working
doors. The body of the furnace is chiefly made of fire-proof brickwork enclosed
in cast-iron frames or casings and held together by iron beams or rails and
tie-rods.
For lifting and turning the furnace, when required, we employ a cylinder con-
taining a piston, which serves as a pivot and can be lifted by hydraulic pressure, as
in Fig. 9, or by means of a screw, as in Fig. 10, or the same cylinder may be
adapted for hydraulic and for mechanical lifting, as in Fig. 11.
In the case of a hydraulic lift, the force pump may supply the water to the
hydraulic cylinder, either with or without the aid of an accumulator, as is usual in
such cases.
"After the furnace has been raised to the required height (say 4 inches) and the
two hearths have been loaded, so as to balance each other as far as convenient, the
furnace is turned 180° by hand or by chains or other suitable means. The discharge
tap from the hydraulic cylinder is now opened, and the furnace allowed to descend,
so that its conical faces fit tightly upon the correspondingly inclined seats formed
on the fixed part of the flues.
The utility of the reversible arrangement in avoiding waste of time and of
heat will appear from the following description of the operation of a puddling
furnace.

page_text: After both hearths have been raised to the required temperatures, the hearth B₁,
nearest to the source of heat, is charged with raw material, and when the latter
has melted down, the rear hearth B, is likewise engaged.
The material in the front hearth B, is now puddled, as usual and finally taken
out, during which time the iron in the hearth B, melts down to a thin fluid.
Subsequently, the furnace is lifted, turned round and allowed to drop, so that the
hearth B₂ is now in front, while the hearth B, is at the back. The molten metal
in B, is puddled as usual, and the fresh charge in B, allowed to melt, after which
the same cycle of operations repeats itself.
The furnace may be heated directly by means of solid fuel burned on a grate,
but we prefer to employ gas generators placed close to the furnace, and to utilize a
portion of the waste gases for heating the air before its admission to the furnace,
while another portion of the said gases serves to heat a steam generator, as
indicated by the drawings.
The recuperator
preferably placed underground close to the furnace, and con-
structed as described in our Application for à Patent No. 6400 of 1890.
It consists
of tubes arranged in separate stacks or blocks D, D, D, in such a manner, as to
allow the gases of combustion to pass between the tubes at a right angles to the.
same, while the air travels through the interior of the tubes alternately from the
front to the back and from the back to the front.
We also form on the underside of the hearth-plates an air-heating chamber,
through which the air admitted at one end travels in a zig-zag course to the
diametrically opposite end, where it is discharged, as indicated in Fig. 3 by dotted
lines. The air chest contains, in addition to the longitudinal main girders, a number
of cross girders or deflecting plates, as shown, and it is provided at the bottom with
a short inlet tube land with an outlet tube . The cross girders may, however,
be omitted. Besides heating air for purposes hereafter described, the air chest
also serves to prevent excessive heating of the hearth-plates.
In the arrangement represented by Figs, 1, 2 and 3, the cold blast is supplied to
the furnace through a pipe ; it enters the wind chest through the inlet l, and
escapes through the outlet, after having been heated by its contact with the
hearth plate of the furnace. Subsequently the air passes through a flue N into the
recuperator (Fig. 2) and is further heated by the same. From the recuperator the
hot blast passes into the horizontal main flue F and thence partly into a vertical
flue O, which supplies the furnace, as indicated by Fig. 1, while the remainder
travels through a pipe P' to the tuyeres or hot blast nozzles Q, which supply hot
air to the generators.
The construction may, however, be modified in such a manner, that the hot air
from the outlet is blown directly to the pipe P and thence to the generator
nozzles, while cold air is blown into the recuperator through the flue E. In this
case the tube is connected directly with the tube P, Fig. 6. If now the furnace
is lifted, then turned 180° and again lowered, the short tubes and will be lifted
out of their sockets and then exchange places, so that the tube i now receives the
cold air, while tube discharges the heated air.
In the arrangement of plant represented by Figs. 4 to 6, we produce in the flue F
and pipe Pan air blast by means of pipes and s supplied with air at a pressure
of 2 to 3 atinospheres. This air blast acts upon injector apparatus R and S, in
such a manner, as to create a suction at the back and a blast in front of the said
apparatus. The suction produced in the pipe P causes cold air to enter the wind-
chest through the inlet and to flow through the outlet into the pipe P, after
having travelled through the wind-chest in the manner indicated in Fig. 6 by the
arrows. The air thus drawn in by the apparatus S is supplied to the tuyeres of the
generators.
In a similar manner, the exhaust action of the apparatus R causes cold air to
enter the recuperator at E and to travel through the same towards the apparatus R,
which blows the air through the vertical flue O into the furnace, as indicated by
the arrows.

page_text: As a rule, we prefer this arrangement to that shown in Figs. 1 to 3.
For heating the recuperator directly from the generators, the furnace is turned
out at 90°, as illustrated by Figs. 7 and 8, the outlet of the cold air supply pipe L,
and the inlet to the hot air flue are covered by caps m', m³ and the outlet from the
generators to the furnace, as well as the inlet of the main flue C, that is to say, the
conically curved seats for the moveable furnace body, are covered by hollow caps, T,
(only one of which is shown in the drawing). These caps may be attached to the
sides of the moveable furnace body, immediately before the latter is turned from its
working position, so that they are turned into the required position by turning the
furnace.
In this case, the air blown into the cold blast pipe L is led through an auxiliary
pipe to the pipe P, from which one part flows to the generator nozzles, while
another part enters the flue F and then the vertical flue O, at the mouth of which
it meets the hot producer gases and produces combustion. The flames or the hot
products of combustion pass through the hot air flue F, then through the con-
secutive blocks of the recuperator, as indicated in Fig. 8 by arrows, and finally
escape through the flue E into the chimney.
During the normal working of the furnace, the valves V and VI are closed.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. A reverberatory furnace having two hearths of the same shape and size placed
one after the other, the said hearths forming part of a moveable body interposed
between the grate or gas generator and the flue for the waste gases, and being
adapted to turn on a vertical axis, in such a manner, that each hearth may be placed
alternately near the grate or generator, while the other is situated near the waste
gas flue, substantially as described and for the purposes specified.
2. A reversible reverberatory furnace as aforesaid provided with conical contact
faces or seats for the moveable furnace body, and with means for lifting the axle or
pivot together with the moveable furnace body, substantially as described.
3. In a reversible reverberatory furnace as aforesaid, an air heating chest formed
on the underside of the hearth-plates, and provided with air inlet and outlet dia-
metrically opposite each other, said air heating chest having partitions adapted to
form a zig-zag course for the air passing from the inlet to the outlet, substantially
as described, and for the purpose specified.
4. The combination of a reverberatory reversible furnace as aforesaid, with gas
generators placed close to the furnace, and apparatus for supplying a hot air blast
to the gas generators, the said apparatus comprising an air heater applied to the
underside of the furnace sole and connected with the cold air supply as well as with
the tuyeres or blast nozzles of the gas generators in the manner substantially as
described.
5. The combination of a reversible reverberatory furnace as aforesaid, with gas
generators placed close to the furnace, and with a recuperator of the type described,
the tnyeres or blast nozzles of the generators being supplied with hot air through
an air heater applied to the underside of the furnace, while the recuperator is placed
close to the furnace and adapted to utilize the waste gases of the furnace for heating
the air supplied to the same, substantially as described.
6. The combination of a reversible reverberatory furnace as aforesaid, with a
recuperator and a steam generator placed close to the furnace, the recuperator being
adapted to utilize a part of the waste gases for heating the air supplied to the
furnace, while the remainder of the said gases serves to produce steam, substantially
as described.
7. The combination of a reversible reverberatory furnace as aforesaid, with gas
generators and a recuperator placed close to the furnace, an air heater applied to
the underside of the moveable furnace body, and air injectors placed in the hot air
conduits, the cold air being conducted first through the air heater, then through the

page_text: recuperator and then in parallel currents to the furnace and the generators, sub-
stantially as described.
8. The combination of a reversible reverberatory furnace as aforesaid, with gas
generators and a recuperator placed close to the furnace, and a pair of caps for
covering the outlet of the generators, as well as the inlet of the flue for the waste
gases when the furnace is turned out at right angles, one of the said caps serving
to conduct the gases from the generators into the hot air flue of the recuperator,
substantially as and for the purpose described.
Dated this 10th day of December 1890.
JOSEPH VON LANGER.
LEONARD COOPER.
By Fairfax & Wetter,
433, Strand, London, Agents.