cupola smelting furnaces
Year: 1886

page_text: I FRIEDRICH AUGUST HERBERTZ of Cologne on the Rhine, Germany, Manu-
facturer. 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:-
My improvements in cupola smelting furnaces will be best understood by
describing the same with reference to the accompanying drawings. Figure 1 is a
longitudinal vertical section, and Figure 2 is a horizontal section of a cupola
smelting furnace for reducing and for smelting ores and metals constructed
according to my invention and Figure 3 is a horizontal section of the exhaust tube.
The parts of the furnace are the following:
S is the body or chamber; H is the crucible and D the steam boiler; E is the
exhausting tube with the injector. The body S is supported by four columns s
being bracketted to them at c. The crucible H of the furnace is a separate
movable part which runs up and down between the columns 8 by means of the
arms or bolsters l. By this arrangement there is a circular opening all round the
furnace between the lower part of the body and the crucible, and any required
size or width of this opening for the admission of the air necessary for combustion
may be made. The raising and lowering of the crucible and, at the same time, the
enlargement and narrowing of the circular opening o is effected by the following
arrangement. Inside the columns 8 there are four screws p with their nuts m
which run in the slits z, and the arms or bolsters ; which are fixed to the crucible,
rest upon the nuts m. If these screws p are turned by means of the hand wheels
placed higher than the brackets c, the crucible is raised or lowered or displaced
and so the aperture o for the draught of air decreased or increased. That an equal
lowering or raising of the crucible may be effected by turning only one crank, one
of the brackets is provided with the communicator (worm and wheel) turning a
chain wheel k which is fixed to the nave of a hand wheel below the latter.
each chain wheel is so attached to a hand wheel and a driving chain runs over the
chain wheels k the motion of the fly-wheel of the communicator v is transferred
to all hand wheels and, of course to all screws p and so the crucible is raised or
lowered equally all round.
As
These furnaces operating with a small vacuum of only 2 or 3 inches of water, the
draught of air entering into the circular aperture o will not be very great, and

page_text: therefore if the body is of a large diameter there will be a space in the shape of a
cone in the midst of the furnace, which is not attained by the current of air, and
no combustion will there take place, or at least, it will be very incomplete.
That this inconvenience may be removed and at the same time, the excess of
heat in the cupola may be used to produce vapour, I establish a boiler D which
surrounds the fire pipe for also several pipes, coming out from the fireplace q in
the vertical axis of the furnace and let them pass through the crucible and the
body of the furnace, as seen in the drawings. By this arrangement I heat the
furnace before it works. The exterior casing of this boiler is concentric with
the body S and its diameter is always proportionate to that of the body S. The
crucible as well as the cone g through which the charging of the furnace is
performed, are so arranged that they, surrounding the casing of the boiler, slide
along the latter, and for this purpose the rivet heads on the rivetted joint of the
boiler plates are countersunk, and for this reason at the same time protected from
being consumed.
The boiler itself is built according to direction. It is fed by an injector under
the fire grate and furnished with a safety pump, and over the mouth of the furnace,
there are water gauges and a water mark, besides the safety valves. The steam is
conducted from the top part of the boiler into the exhauster and empties itself into
a series of tubes J placed around the centre of the exterior tube E and requiring
the same number of injectors i, i as there are tubes J, which number may vary.
The exhaust which takes place is effected not only through the tubes a of the
series, but also through the opening in the midst of this series and through the
openings between the series and the exterior tube E at a, and a².
The exhausting tube E which in the drawings of the Specification of my previous
patent dated 1st January 1886 No. 27 was fixed to the top part of its body, enters
now into the furnace immediately above the melting zone, about in the middle of
the body. In that place inside the lining of fire bricks there is the annular
channel K perforated at F, which holes are open towards the interior of the body.
By this arrangement the exhaustion is effected by the exhauster through the
holes and the annular channel K. I reserve to myself to use one or several
exhausters and to unite them with the channel K.
The advantages of such an exhaustion are
a.) less friction of the gases with the charges in the furnace.
b.) the height of the mouth is not limited.
c) the mouth need not be shut hermetically.
d.) the exhausting tubes are more protected from being consumed by fire.
Sometimes I substitute for the steam boiler D a single tube closed at the bottom
and open at the top which is filled with water. This tube must however have the
same diameter as the boiler D; it is regulated according to the diameter of the
furnace shaft. The tube filled with water has thus only the object before stated
being formed in the middle of the shaft, and to fill up space unserviceable for the
smelting.
Having thus particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed. I declare that what
I claim is:-
1st. In cupola smelting furnaces the arrangement therein of a steam boiler or of
a corresponding tube open at top and closed at bottom which is heated previous to
the working of the furnace by a fire grate provided for the purpose, and during
the working, by the charges in said furnace whereby steam is produced for causing
an exhaustion of air, substantially as described.
2nd. The arrangement of an annular injector like exhaust, consisting of a series
of tubes F and injectors i inside the exhausting tube E as set forth.
3rd. The arrangement of an annular channel K inside the lining of the 'furnace
and immediately above the smelting zone, which channel Kis in communication
(by holes F) with the inside of the said furnace, and on the other side with the

page_text: exhausting tube E of the injecting apparatus substantially as described and
illustrated with reference to the accompanying drawings.
4th. The general arrangement and construction of cupola smelting furnaces
consisting essentially of a circular opening between lower part of body and crucible,
with means as described for adjusting width of same; and with boiler D and
exhaust E and parts relating thereto substantially as herein set forth with reference
to the accompanying drawings.