improvements in Furnaces for the Manufacture of Steel.
Year: 1886

page_text: improvements in Furnaces for the Manufacture of Steel.
We, ROBERT MILLER of 37 Melville Street, Motherwell, in the County of
Lanark, Shingler, and NORMAN ERSKINE MACCALLUM. of Fairbank, Helensburgh,
in the County of Dumbarton, Chemist, 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:-
This invention relates to furnaces for the conversion of pig iron into steel the
improved furnace being so arranged that the Bessemer or Pneumatic a and the
Siemens or Open Hearth modes of working are so combined as, to obtain.
the rapidity of the former with the facilities and advantages for sampling which
the latter possesses.
On the accompanying drawings, figure 1 is in part a side elevation and in part
a longitudinal vertical section of the furnace as constructed in accordance with our
said Invention. Figure 2 is in part a plan and in part a horizontal section of the
furnace. Figure 3 is a transverse section of the furnace on the line a, b figure 2.
Figure 4 is a transverse section on the line c, d figure 1 and figures 5, 6 and 7, are
details hereinafter more particularly referred to.
The furnace proper is as shewn by the drawings, preferably octagonal in plan
and it has its roof dome shaped and formed with an opening A, at the centre the
said opening having a movable cover B, which is constructed in two halves or
portions. At the side or at any other convenient part of the furnace an hydraulic,
steam or other cylinder C, is situated vertically the ram, plunger or piston of which
is connected to a telescopic blast pipe C, which at its lower end has two branch
tubes D, the vertical part of each of which is covered or protected with a coating
or jacket of refractory material and furnished at its lower end with a detachable
box E, more particularly seen in vertical section at figure 5, the said box containing
tuyeres. The box which may be of cast iron, wrought iron or steel, is made in two
parts tied or bolted together and it has the lower part of the interior sloping or
inclined inwards. The tuyeres F, which are made of fireclay or other refractory
material are or may be moulded in four or more segments as indicated at figure 7,
each segment having a series of vertical holes or passages formed through it the
upper part of each segment being bevelled at an inclination corresponding to that
of the sides of the box E, whilst the lower part from the bottom upwards to the
under part of the box projects so as to carry or support a refractory jacket or
casing G, for the sides of the box, the said jacket and also a protecting cover H,
for the top of the box being composed of fire clay, ganister, bricks or other refrac-
tory material. By this arrangement when the two halves of the box E are bolted
together by the tees or bolts I, the segments of the tuyere are clamped and securely
held in position.
Under an alternative arrangement the tuyeres may be made in the usual way
adopted for Bessemer vessels or converters, that is to say, they may be fixed to the
apper part of the box E, and packed with ganister or fireclay.

page_text: The box E, with the tuyeres F, is lowered into the furnace through the
opening A, the cover B, being first removed, and through the tuyerês atmospheric
air is forced into the molten metal. By connecting two tuyere boxes to the ram
or plunger of the hydraulic or other cylinder C, one is in readiness for use in case
of accident or whilst the other is being repaired and to provide for the air current
being directed to either tuyere as desired or reversing valve is inserted in the air
pipe at J, figure 1.
Regenerators are built at each side of the furnace as indicated at K, figures 1
and 2 of the drawings the passage of gas and air through these regenerators being
regulated in the usual way.
The gas passage M, is at the top of its vertical part divided into two channels N,
as indicated at figures 2 and 3, each channel N, having slag openings J, as seen at
figure 4, these being furnished with movable covers O, under which small bogies P,
may be placed to receive the slag. The air port L, may have one opening or it
may be divided into two or more ports and the furnace may have one or more
doors Q, so arranged that they can be secured during the period of blast.
The furnace is fitted with a movable bottom R, and opposite the tap hole S, or
at other convenient part an opening T, is provided for charging the molten pig
iron, etc; into the furnace.
on.
In working with the furnace constructed as herein before described the molten
pig iron is charged through the opening T, either direct from the blast furnace or
from cupolas, the cover B, is removed from the opening A, in the roof, the gas from
the generators is turned off and the air blast from the tuyeres F, is gently turned
The tuyere box E, is then lowered by the ram or piston of the hydraulic or
other cylinder C, until the tuyeres F, are several inches in the metal and the blast
is continued at an increased pressure for about fifteen minutes or until the metal is
sufficiently decarburized. The tuyere box E, is then withdrawn and the gas turned
on, samples of the metal are taken and the process of manufacture is completed as
in the ordinary open hearth furnace.
The furnace affords special advantages for the use of basic lining and it will be
seen that with it the rapidity of the Bessemer process and the facilities for sampling
and adding scrap, or ore to the charge which the Siemens process affords are com-
bined, further the heat presently wasted in working with the ordinary Bessemer
converter during the blowing period is conserved in the regenerators and utilized
during the sampling of the metal, and the furnace has also the advantage that the
pressure of blast required is less than with the Bessemer process, that little or. no
slag can enter the regenerators and that the general arrangement renders all parts
easily accessible for repairs.
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. A furnace for the manufacture of steel constructed and arranged substantially
as hereinbefore described with reference to the appended drawings.
2. The combination of the hydraulic, steam or other cylinder C, and telescopic
blast pipe C¹, with branches D, carrying tuyere boxes E, and tuyeres F, substantially
as described with reference to the accompanying drawings.
1000