Improvements in Melting Furnaces.
Year: 1895

page_text: Date of Application, 18th June, 1895-Accepted, 20th July, 1895
Improvements in Melting Furnaces.
We, SAMUEL THOMAS WELLMAN and CHARLES HENRY WELLMAN, of
Upland, Delaware County, State of Pennsylvania, one of the United States of
America, Mechanical Engineers, 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 :-
The object of our invention is to construct a partially rotatable melting furnace
with the hearth of the furnace situated between ports or passages for gas and air
situated at the ends of the furnace, the said furnace being of cylindrical or such
equivalent form that it can be rolled forward and turned into position to discharge
its contents.
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We will describe our invention with reference to the accompanying drawings:-
Figure 1 is a side view of a melting furnace constructed according to our
invention.
Figure 2 is a longitudinal section of the same.
Figure 3 is a transverse sectional view on the line 3-3, Figure 2.
Figure 4 is a transverse sectional view on the line 4-4, Figure 2.
Figure 5 is a similar view to Figure 4, showing the furnace in the position for
discharging.
Figure 6 is a cross section of a slightly modified form of furnace.
Figure 7 is a longitudinal section of one end of a furnace adapted to burn gas
or oil.
Figures 8 and 9 are sections at right angles to each other of a cylindrical
furnace in which the passages for the air and gas are in the stationary part of the
furnace the joint being made at the hearth; and
Figure 10 is a sectional plan view on the line 5-5, Figure 1.
In the construction of the ordinary melting furnace the walls must necessarily
be built very heavy and braces and tie rods have to be used in order to hold the
walls together, but in a furnace constructed according to our invention, the
movable part of the furnace being of cylindrical or nearly cylindrical form in
transverse section, common bands or hoops may be used, as the walls are to a certain
extent self-sustaining.
A A are foundations in which are formed regenerating chambers A¹ and slag
pockets A, B is the melting furnace preferably cylindrical in cross section, as shown
in Figure 3, and supported at each end on the foundations A A. B' is the hearth
on which the metal is melted; this hearth is of the ordinary construction and on
each side of the hearth within the brickwork of the furnace are air ducts & through
which air passes and serves to cool the bricks to a certain extent.
In each end of the furnace are gas ports c and air ports d, clearly shown in
Figures 2 and 3, these gas and air ports communicate with the combustion chamber
above the hearth B₁ of the furnace, as clearly shown in Figure 2. We preferably
separate the gas and air ports at the base of the furnace where they join the
foundation by a space a formed in the furnace and open to the atmosphere so that
the gas or air under pressure that should escape at the joint will not mix in the
passages but will simply escape to the atmosphere; the air space may be formed in
the foundation in some instances, and we preferably build in the furnace water
jacketted seats at the joints of both the gas and air passages so as to keep the
parts cool, the seats may be carried either by the foundation, as shown in Figure 2,
or by the movable part of the furnace.

page_text: The furnace is provided at each end with a toothed segment D engaging in
racks D' on the foundation or on a frame extending from the foundation, which
segments can be mounted in the spaces a between the air and gas ports, as shown in
Figure 2, or they can be arranged inside the ports nearer the furnace centre, as
shown in Figures 7 and 8.
Connected to each end of the furnace at ee are piston rods E of hydraulic
cylinders E pivotted at e¹ to the foundation, and provided with fluid pipes e², e³,
communicating with the upper and lower ends of the said cylinders these pipes
being provided with or connected to suitable valves or regulators for regulating
the flow of liquid into and from the cylinders.
g is the charging aperture to the furnace B and i is the discharging opening
provided with a lip or spout . In operation the furnace is charged through the
door g from the charging floor and gas and air are supplied through the ports at
one end of the furnace and the products of combustion escape through the ports at
the opposite end and when the metal is in a condition to be discharged from the
furnace fluid under pressure is admitted to the upper portion of the cylinders E'
which will force down the pistons and cause the furnace to roll forward and at the
same time tilt or tip into the position shewn in Figure 5 so as to discharge the
contents into a suitable receptacle. As soon as the molten metal has been
discharged, the fluid under pressure is admitted to the opposite ends of the
cylinders E to return the furnace to its normal position shewn in Figure 4.
In some instances the furnace may be made oval in cross section, as shown in
Figure 6, and where natural gas or oil is used the furnace may be constructed as
shown in Figure 7, an air passage being provided at the base and a gas inlet being
provided at the side of the furnace.
In Figures 8 and 9, we have shown a furnace in which the gas and air ports are
built with the foundation and the joint made on the line v the central or hearth
portion of the furnace only being movable.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. The combination in a melting furnace, of the foundation, air and gas passages
therein, a hearth section having passages communicating with the said air and gas
passages of the foundation when the blast is on, with means for rolling the hearth
section. forward. and away from the said air and gas passages to discharge the
contents, substantially as hereinbefore described.
on,
2: The combination in a melting furnace, of the foundation, air inlet passages
therein, a rack on the foundation, a cylindrical furnace section having a hearth and
passages adapted to align with the passages in the foundation. when the blast is
a segmental gear on the cylindrical section meshing with the teeth of the rack, and
means for,. rolling the said section so that it will move forward to discharge the
molten metal, substantially as hereinbefore described.
3. The combination in a melting furnace, of the foundation having air and gas
ports at each side or end, a cylindrical hearth section also having air and gas ports
at each side, or end and aligning with the ports in the foundation when the furnace
is in action, a rack on the foundation and a gear on the hearth section meshing with
said rack, with a cylinder and piston, one connected to the foundation and the other
to.the hearth section so that when pressure is applied to one side of the piston the
furnace will be rolled forward, substantially as herein before described.
4.. The combination of the foundation, air and gas passages and a rack at each
side or end, of the foundation, a cylindrical hearth section, gears thereon meshing
with the racks, air and gas passages one on each side of each rack and aligning
with the passages of the foundation when the furnace is in action, a pouring
opening, in, the hearth section, and means for turning said section so that it will
roll forward and discharge its contents, substantially as herein before described.
5. The combination of the foundation, air and gas passages therein, a hearth

page_text: section having air and gas passages at each side or end adapted to rest over the
passages in the foundation when the furnace is in action, means for rolling the said
hearth section forward, an air channel between each air and gas joint so that the
air and gas ports will not communicate with each other at the joints, substantially
as hereinbefore described.
6. The combination in a melting furnace, of the foundation, air and gas passages
therein, a hearth section having passages communicating with the said air and gas
passages in the foundation when the blast is on, a fixed track and means for rolling
the hearth section forward on said track without elevating it, substantially as
hereinbefore described.
Dated this 18th day of June 1895.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.