Improved Heated Blast Cupola.
Year: 1899

page_text: Improved Heated Blast Cupola.
WILLIAM LITTLETON, 22, Werndee Road, South Norwood, in the County of
Surrey, Mechanical Engineer, do hereby declare the nature of this invention
to be as follows:―
The object of this invention is to economise fuel in melting.
In carrying out this invention the air blast is forced through a chamber or
belt formed in the upper part of the cupola lining immediately above the melt-
ing zone. This part of the lining is constructed of series of cast iron segments
of suitable section to form the chamber or belt through which the air is forced
on the way to the tuyeres.
By reason of the position of this air chamber or belt at a part of the furnace
above where the melting takes place, the heat absorbed by the air passing through
the chamber or belt has no detrimental result upon the melting the same being
more rapid due to the heating of the air blast. The air blast leaving the chamber
or belt at the under side passes through connection formed in the lining to the
tuyeres either the upper or lower series and thence to the hearth of the furnace.
The hearth is so formed as to allow the greatest area of the fuel forming the bed
charge free exposure to the air blast thereby utilising all the fuel that remains
upon the hearth at any time for melting at the same time the depth is, such as to
minimise the bed charge considerably even when the cupola is not used in con-
nection with a receiver, but when a receiver is used the proportion of bed charge
to iron melted is very much less and consequently lowers the average proportion
of coke to iron for the heat or run.
In order that the tuyeres may be used all at the same time or in series valves
are fitted at the passages for the control of the air blast.
Dated this Eleventh day of July 1899.
Improved Heated Blast Cupola.
WILLIAM LITTLETON, 22, Werndee Road, South Norwood, in the County of
Surrey, Mechanical Engineer, 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:
-
In carrying out this invention the outer part of the cupola is constructed in
the ordinary way, of stout wroughtiron or steel plates with or without receiver
to retain the molten metal as it flows from the cupola.

page_text: The inner part or lining is of a special form, composed of two parts the upper
and lower.
The upper part is formed of a series of cast iron segments of suitable section
to form the chambers through which the air is forced from the blower on the
way to the tuyeres.
By so forming this chamber or belt at a part of the furnace just above the melt-
ing zone, the heat absorbed by the air blast passing through the chamber or belt,
has no detrimental result upon the melting the same being more rapid owing to
the greater heat produced from the fuel and freedom from slag accumulating
opposite and around the tuyeres.
The air blast is conducted from the belt at the underside by vertical passages
formed in the lower lining to the tuyeres supplying the hearth.
The hearth is so formed as to give the greatest area of the fuel forming the
bed charge, free exposure to the air blast, thereby utilising all the fuel that
remains upon the hearth at the same time for melting, the depth of the bed
charge of fuel is such as to minimise the same when the cupola is not fitted with
a receiver, and more so when same is added.
By the reduction of the bed charge of fuel the metal and slag are made to flow
rapidly from the furnace thereby saving both time & fuel.
Fig. 1 of the drawing herewith shows a vertical section of cupola and receiver
the arrows denote passages through which the air blast is forced through the
belt A & B to the tuyeres.
Fig. 2 shows horizontal section at 1) the lining constructed of fire clay bricks.
Fig. 3 shows horizontal section with air blast inlet at A the lining constructed
of cast iron sections.
Fig. 4 shows horizontal section at B the lining constructed of cast iron sec-
tions forming the lower part of air blast belt.
Fig. 5 shows horizontal section at C the lining is constructed of fire clay bricks
of suitable shape to form passages and tuyeres for air blast to enter hearth.
Fig. 6 shows plan of two sections forming part of air blast belt, A & B, the
grooves formed at the vertical joints, these sections built up in complete rings,
having metal rods driven into the grooves, thereby making the vertical joints
air tight.
The nadial joints of cast iron sections forming air blast belt are made with fine
clay, the joints in bond as in ordinary brickwork.
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
(1) In an arrangement of cupola for melting metals slags and the like with
the air blast belt or chamber formed in the upper part of lining above the melt-
ing zone so as to heat the air blast before it enters the tuyeres.
(2) Constructing the air blast belt or chamber as described by series of cast
iron sections so arranged and jointed with grooves formed at the inner edges
nearest the centre of cupola and fitted with metal strips or rods either, round
square or any suitable section to form air tight joints.
(3) The space of air belt or chamber so formed and divided as to make one or
more complete rings or anular spaces between the cupola lining and outer
casing through which the air blast is forced, and so forming a large amount of
heating surface, for heating the air blast before it enters the tuyeres or the
furnace.
(4) Forming the lower part of cupola, known as the hearth, as described
together with the position and arrangement of tuyeres.
1000
WILLIAM LITTLETON.