IMPROVEMENTS IN FURNACES FOR MELTING METALS BY A NEW OR IMPROVED PROCESS to be as follows
Year: 1884

page_text: I JOHN HODGKINS, Foreman Caster to R. Disturnal & Co of Bridge Works,
Wednesbury, in the County of Stafford do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN FURNACES FOR MELTING METALS BY A NEW
OR IMPROVED PROCESS to be as follows:-
""
In carrying out this Invention a furnace is constructed in the following
manner :-
The bottom of the furnace is preferably plated and covered with sand or plumbago
hollowed to form a channel and slanting down towards a space in the flue in which
is placed a crucible which receives the metal as it runs from the furnace bottom.
A perforated bridge is provided which retains the coke and pig metal but allows
the flames to pass and join those which pass over the top of the bridge; the whole
enveloping the crucible and keeping the metal which first runs into it hot until
the whole charge has run.
The flue is continued to another space in which is placed the pig metal to be
heated to a red heat previous to being melted. The flue is then conducted to a'
drying stove for cores &c., so that the whole of the heat may be utilized-The
blast pipe is carried in the walls of the furnace so that the blast may become
sufficiently hot, and terminates in tuyers which discharge into the furnace.
Suitable doors, lids &c. are provided to afford access to the various parts of the
furnace & flues.

page_text: I JOHN HODGKINS, Foreman Caster to R. Disturnal and Co Bridge Works
Wednesbury Staffordshire do hereby declare the nature of this Invention for
"IMPROVEMENTS IN FURNACES FOR MELTING METALS BY A NEW OR IMPROVED
PROCESS" and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
In carrying out this Invention a furnace is constructed in the following
manner :-
The bottom of the furnace is preferably plated and covered with sand or
plumbago hollowed to form a channel and slanting down towards a space in the
flue in which is placed a crucible which receives the metal as it runs from the
furnace bottom-A perforated bridge is provided which retains the coke and pig
metal but allows the flames to pass and join those which pass over the top of the
bridge, the whole enveloping the crucible and keeping the metal which first runs
into it hot until the whole charge has run.
The flue is continued to another space in which is placed the pig metal to be
heated to a red heat previous to being melted.
The flue is then conducted to a drying stove for cores &c. so that the whole of
the heat may be utilized. The blast pipe is carried in the walls of the furnace so
that the blast may become sufficiently hot and terminates in tuyers which discharge
into the furnace. Suitable doors lids &c. are provided to afford access to the
various parts of the furnace and flues.
In the accompanying Drawings Figure 1 is a sectional side view Figure 2 is a
section on line Z. Z.
Figure 3 is a back view of Figure 1 showing the metal
chamber G in section. Figure 4 is a front elevation. Figure 5 is a side elevation.
Figure 6. is a sectional plan upon line Y. Y. Figure 1. Figure 7 is a sectional
plan upon line X. X. Figure 1. Figure 8 is similar to Figure 1 but is adapted
for use without a blast and Figure 9 is similar to Figure 2 but is adapted to a gas
apparatus.
The furnace may be constructed of brickwork lined with fire bricks and held
together at the sides by cast iron plates, with the rods across over the top in the
usual manner.
The Drawings show the furnace in its different parts suitable for a 120 lb.
"crucible" but it can by increasing or decreasing its size be adapted for larger or
smaller crucibles. Figures 1. 2 and 6 is the furnace in which the iron and fuel is,
placed. This has a sand bed W bottom placed upon an iron plate T built in the
brickwork in which is an opening Q for the purpose of running out the sand
bottom when broken up for renewal, below this plate is another sliding plate T'
resting upon iron bearers. This lower plate T₁ is for the purpose of supporting
the sand bed under the aperture in the upper plate and when drawn out it lets the
Band fall into the open space D below it." The sand bed is of a curved shape as
shewn in Figure 2 sloping down to the back of the furnace as shown in Figure 1.
so that the metal immediately it becomes liquid will flow to the spout N. Figures 1
and 6: which conveys the metal direct into the crucible placed in the crucible
chamber F so that the metal is at once removed from the fire and so prevents its
nature being injured or destroyed by burning.
The furnace is covered with a fire brick arch in sections, held in iron clamps so
that it can readily be removed for relining or repairing the furnace.
The metal is melted by the heat generated from coke or charcoal into which a
blast of hot air is forced through the blast pipes enclosed in the brickwork of the

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fornace which pipes discharge through the tuyre's or blast holes V in Figures 1
and 2 the course of the blast pipes being shown in Figures 1. 3. 5 and 6.
<<
At the back of the furnace is a bridge" through the lower part of which the
spout H passes and projects over the crucible as shewn in Figure 1. also there are
two openings at the lower part and one at the top of the "bridge" for the flame
and heat to pass into the crucible chamber F and play round the crucible containing
the molten metal.
I do not bind myself as to the number of apertures in the bridge but those
given are found to answer well.
From each side of the furnace at the top extends a flue R in Figures 1. 2. 6
and 7 formed in the side walls and carried down to and opening out into the lower
part of the crucible chamber Figures 1. and 7; these flues conduct the waste heat
from the furnace to the bottom of the crucible so that in conjunction with the
waste heat passing by the bridge round the crucible, the metal in the crucible is
kept in a molten state until the whole charge is melted and run into the
crucible.
From the crucible chamber F the heat passes through the openings P Figures 1. 3
and 7 into the metal chamber G where it heats the metal intended for the next
charge, so that the waste heat is further utilized to heat each successive charge of
metal previous to being put into the furnace. From G the waste heat passes to
the flue and may be further utilized to heat drying stoves for cores &c.
The metal chamber G is covered by loose fire clay lumps or bricks held in iron
clamp frames which are easily pushed aside for the purpose of putting in or taking
out the metal.
The crucible chamber F is closed by the door L Figures 5 and 7. formed of fire
clay lumps and iron.
The furnace E Figure 1 is first filled with coke or charcoal up to the level of the
bottom of the door J and then the metal is taken from the chamber G and placed
on the top of the coko or charcoal through the door J, the door is then closed and
the "blast" turned on at the valve S. (Figures 1. 3, 5 and 6. which is fixed on the
blast culvert. H Figure 7 after the charge is melted and run into the crucible the
door L Figures 5 and 7 is opened and the crucible removed by the tongs shewn at
Figure 5.
At each side of the furnace are small openings M Figures 2 and 5 stopped by
taper plugs fitting into the iron side plates and through which the tuyeres or blast
openings can be cleansed while the furnace is working from any obstruction that
may get into them.
At the back of the furnace is a small opening T Figures 1 and 3 for the purpose
of inspecting the crucible and the metal in it, this opening may be closed by a fire
clay lump placed against it.
At K Figures 1 and 4 is an opening in the front of the furnace for the purpose
of clearing out and removing the unconsumed coke at the end of the day and also
for repairing and forming the furnace bed E Figure 6.
On the bottom of crucible chamber E there is an outlet at the back see Figure 7
so that the slag may run off should the crucible be over filled.
When this furnace is used without a blast I provide air holes a a through the
wall of the furnace (Figure 8) and just above the sand bed there are preferably
three of these on each side and one in the fire door K so as to supply sufficient air
to the furnace. These may in general be left permanently open. Above these
again I place other holes 6 b so as to supply air to the furnace higher up when
required; these should be provided upon the outside with stoppers or covers so that
they may be closed when the level of the fuel sinks below them and no more cold
air admitted when not required.
Figure 9 shews a section of the furnace when intended for heating and melting
the metal by gas instead of coke or charcoal the alteration in the furnace consisting
of the lowering of the arch dispensing with the blast pipes and substituting the

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necessary well known gas apparatus in the working of the furnace the metal would
be placed upon the sand bed and the operation would be the same as above
described.
Having now described this Invention and in what manner the same is to be
performed I declare that what I claim is
First. The combination with a furnace for melting metal the employment of a
crucible or equivalent receptacle so placed in the flue or path of the waste heat
from the furnace as to receive the metal when it runs and maintain the heat until
the whole charge has "run" substantially as described and illustrated.
Second. The method substantially as set forth of keeping the whole body of
metal in the crucible or other receptacle at a uniform temperature by conveying in
addition to the heat otherwise supplied to the vessel a portion of the waste heat
from the furnace direct to the lower portion of the receptacle substantially as set
fortb.
Third. In a crucible furnace the method substantially as set forth of heating the
metal before it goes into the furnace by placing it in the flue from the furnace.
Fourth. The inspection aperture T so arranged that both crucible and spout can
be inspected and operated upon while the melting is in progress substantially as
set forth and shown.
Fifth. The openings M by which the tuyers can be cleared of obstruction while
the blast is on substantially as described and shown.
Sixth. The combination with the sand bed W of the plates T (provided with the
opening O and T¹) whereby the sand bed is supported until plate T is withdrawn
when the sand bed can be discharged into the space D substantially as described
and illustrated.
Seventh. The special construction of furnace for use with gas apparatus
substantially as described and illustrated in Figure 8 of the Drawings.
Eighth. The special construction of furnace for use without a blast substantially
as described and illustrated in Figure 8 of the accompanying Drawings.
Ninth. The special construction of furnace for use with gas apparatus 3
substantially as described and illustrated in Figure 9 of the Drawings.
Dated this Twenty-seventh day of May 1884.