Year: 1887

page_text: Date of Application, 26th Aug., 1887
Specification Accepted, 25th Oct., 1887
1, FRIEDRICH AUGUST HERBERTZ of Cologne on the Rhine, Germany Manufacturer
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:-
Hitherto furnaces worked with whatever kind of mechanism for the production of
a high wind pressure or blast have been subject to the following disadvantages.
1. The consumption of coke is very great as the coke in consequence of the pressuro
is not reduced to carbonic acid but to carbonic oxide and instead of 6000 units of
caloric there are only 2000 free.
2. Through the combustion of the carbon of the raw material, the quality of the
cast obtained is considerably deteriorated, or in other words, for the production of a
directly serviceable cast, a raw material rich in carbon and therefore expensive has to
be employed.
The object of my invention is to obviate these disadvantages by an arrangement of
smelting furnace provided with steam jet, and mainly by a considerably increased
heating of the air for combustion which ensues.
In order that my invention may be fully understood and readily carried into effect
I will describe the same with reference to the accompanying drawings.
Figure 1 is a vertical section illustrating one form of cupola constructed and
arranged according to my invention. Figure 2 is a horizontal section on the line a y
of Figure 1. Figure 3 is a horizontal section on the line y of Figure 1. Figure 4
is a vertical section taken at right angles to the view shown at Figure 1, of a similar
cupola constructed according to my invention but in which the air conducting passages

page_text: slightly differ. Figure 5 is a horizontal section on the line ² y² of Figure 4; and
Figure 6 is a horizontal section on the line ³ ³ of the same figure.
S is the shaft of the smelting furnace supported on pillars s. Under the shaft S is
the crucible or hearth H which by means of spindles and bevel or mitre wheels inside
the said pillars, can be moved up or down as required. By the suction or exhaust
apparatus composed of the pipes A and a and the steam jet F the formation of a
vacuum is induced in the shaft which is closed at the top by the movable bell cover G.
The outside atmospheric air will enter through the free annular and adjustable air
opening O, between the under level of the bottom of the shaft and the upper level of
the crucible or hearth and an intense combustion and fusion will be produced.
Smelting furnaces constructed according to my invention with steam jet have no
over fire in the upper portion of the shaft, and the fusible ore lies closely compacted
in the under part of the shaft immediately over the annular air passage O. Therefore
over the smelting ore and up to the top of the shaft a heating of the shaft takes place
which does not reach to smelting point but which can nevertheless be used with great
advantage for the heating of the combustion air.
Acting upon this I place in the upper portion of the shaft instead of the so called
Chamotte lining an iron air chamber W see Figs. 1 and 4; from the bottom plate of
this air chamber W a suitable number of iron tubes R Figs. 1 and 3 run downwards
and discharge into the nozzle pipes D which latter pass from the outside and commu-
nicate with the smelting ore. The nozzle pipes I can be opened or closed by means
of valves. In the upper portion of the air chamber W air entrance holes L are
provided as shewn at Figures 1, 2 and 4.
As soon as the steam jet F is brought into action and the annular air entrance
opening O, according to the desired heat, is either wholly closed or only a little open,
the outside atmospheric air enters the air chamber W through the air entrance
openings Land is conducted from thence through the tubes R Figs. 1 and 3 which
are embedded in the Chamotte lining (or which may in some cases be placed outside
same) and through the nozzle pipes D reaching the smelting ore heated to
600° R.
Instead of the system of pipes R which conduct the heated air from the air chamber
to the smelting ore, a circular canal K of annular cylindric form, see Figures 4 and 5
proceeding from the air chamber W and opening into the annular air entrance
opening may be used, to serve as a conductor of the heated air to the furnace. In
this case the entrance of the cold air through the opening O is obstructed by circular
covering plates N by which the said annular air opening O is or may be closed from
the outside.
In some cases the air may be forced into the air chamber W by mechanical means
through the air openings L and the exhaust apparatus dispensed with, the current of
air would in this case, as before, reach the smelting ore in a heated state. Or a com-
bination of suction and compression of the air may be employed all as desired and
according to circumstances.
Having now 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 with or without steam jet or exhaust apparatus ;
the construction and employment of the heated air conductor, composed of one or
more air heaters set in the upper and inner portions of the shaft in place of the so
called Chamotte lining; whereby heated air is conducted to the furnace through or
near to, the annular air entrance opening O, by means of tubes or a circular canal
or annular cylindric passage within or outside the said lining, either for the smelting
of metals or for the burning of malachite, dolomite and similar stones substantially as
herein set forth.
2nd. In cupola smelting furnaces with exhaust and compressive air supply appa-
ratus; the construction and employment of the heated air conductor composed of air
heater or beaters, set in the upper and inner portion of the shaft in place of the so

page_text: called Chamotte lining, with conducting tubes or circular canal within or outside said
lining whereby heated air is conducted to the furnace through annular opening O
or through nozzle tubes D either for the sinelting of metals or for the burning
of malachite, dolomite and similar stones substantially as herein shewn and
described.
3rd. The general arrangement, construction and combination of parts composing
my improved cupola sinelting furnace substantially as herein shewn and described
with reference to the accompanying drawings together with any mere modification
or modifications thereof.