Improvements in the Manufacture of Steel.
Year: 1896

page_text: Date of Application, 4th Apr., 1896-Accepted, 16th May, 1896
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Steel.
We, FRANK BERNARD LAST, Manager to The Swansea Hematite Iron
Company Limited, of Landore, South Wales, and JOHN ROPER WRIGHT of Elba
Steel Works, Gowerton, near Swansea, South Wales, Iron and Steel 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:-
The object of our invention is to effect improvements in the manufacture of steel
in the Siemens-Martin or Pernot or other open hearth furnace and we accomplish
this by supplying air or steam or both to the molten mass through movable tuyeres
which can be moved about to different parts of the bath and thus disseminate the
air or steam as desired.
To carry out our invention we may either take molten iron from a blast furnace
metal mixer cupola or other like furnace and introduce it directly into a Siemens-
Martin Pernot or other open hearth furnace (whether acid or basic) or in lieu of
such molten metal we may melt pig iron or may take a mixture of the two. One
or more discharge nozzles tuyeres or blast jets preferably with somewhat large
outlet or outlets (say for example with an outlet of at least one inch cross-sectional
area) are inserted into the charge near the bottom thereof. These are movable
and may be conveniently arranged by being swivelled near the apertures in the
open hearth as they then can rapidly be moved about to any part of the charge
where air or steam or both may be required. They are directed downwards to such
a spot as is convenient for the purpose and are moved about in the charge while the
air or steam or both are forced through at a suitable pressure which must depend
on the depth to which their outlets are immersed below the surface of the charge.
When the temperature has increased sufficiently iron ore can, if required be
introduced and the treatment be carried on as usual in open hearth processes. The
forcing in of air or steam or both in the manner aforesaid can be continued until
the silicon and carbon are nearly or wholly eliminated. Any convenient arrange-
ment of the apparatus for conveying or injecting the steam can be adopted provided
that the requisite facility for moving the ejecting devices in the charge be provided
and the air and steam be at sufficient pressure. Preferably I attach to the injecting
apparatus taps whereby the supply of air or steam can be regulated. The pipes
which form the ejection apparatus may be introduced by the doors or ordinary
openings or by openings specially provided for the purpose and can be moved about
in the charge by hand or by mechanical means. The connections between the pipes
and the sources of air or steam under pressure may be conveniently made by
flexible metallic tubing of a suitable kind.
Owing to the flexible connections the pipes coustituting the tuyeres or blast jets
can be moved about in the molten charge and the air directed in such a way as to
cause the whole of the molten charge to be thoroughly submitted to the action of
the air or steam or both a matter which is essential to success. The injection of
air or steam or both can be stopped at any point according to the quality of steel
required.
In order that our invention may be fully understood we will now proceed to
describe the same with reference to the annexed sheet of drawing.
Figure 1 represents in vertical section and Figure 2 in vertical plau a Siemens-
Martin furnace provided with an arrangement of blast distributing jets according
to this invention.

page_text: A is the hearth of the furnace to which molten metal is conducted by the metal
runner a direct from the blast furnace or cupola or other furnaces in which it has
been reduced or melted. B is the crown of the furnace and C are the regenerative
arrangements.
A suitable blast main F and storage of air or steam or air and steam under
pressure are provided and from the said main are led flexible pipes D which
terminate in nozzle pipes E say of cast iron with an orifice of from one to two
square inches cross sectional area of outlet. These are protected by sleeves of
refractory material such as fire-clay. The said pipes may be provided with cocks G
by which the pressure of the air or steam or both can be regulated so as to give
the proper degree of ebullition of the charge during the process.
As soon as the air or steam or both, are admitted, gas can be almost turned off
as sufficient heat is generated during the treatment, the gas being again turned on
near the end of the operation and during finishing in the ordinary way. The air
or steam or both air and steam should be turned on before the pipes are introduced
into the charge.
We have shewn in Figure 2 five separate single nozzles led in one side but more
or less can be used as desired and they can be introduced through the ordinary
doors or openings or through special openings provided for the purpose in the side
wall or walls of the furnace. Figure 3 shews three pipes led in from one side with
outlet openings from the side of each pipe, and Figure 4 shews pipes led in from
each side.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. The manufacture of steel by introducing molten iron from a blast furnace,
cupola or the like direct into a Siemens-Martin or Pernot or other open hearth
furnace and then forcing air or steam or both air and steam into and through the
molten charge the injecting device being moved about in the charge so as thoroughly
to subject it to the action of the air or steam or both substantially as hereinbefore
described.
2. The manufacture of iron or steel by melting pig iron in a Siemens-Martin or
Pernot or other open hearth furnace and then forcing air or steam, or both air and
steam into and through the molten charge as aforesaid the injecting device being
moved about in the charge so as thoroughly to subject it to the action of the air or
steam or both, substantially as hereinbefore described.
3. The manufacture of steel by introducing molten iron from a blast furnace,
cupola or the like direct into a Siemens-Martin or Pernot or other open hearth
furnace and then forcing air or steam or both air and steam into and through the
molten charge as aforesaid the injecting device being moved about in the charge so
as thoroughly to subject it to the action of the air or steam or both substantially
as hereinbefore described and adding ore and finishing the charge in the
ordinary way.
4. The manufacture of steel by melting pig iron in a Siemens-Martin or Pernot
or other open hearth furnace and then forcing air or steam, or both air and steam
into and through the molten charge as aforesaid the injecting device being moved
about in the charge so as thoroughly to subject it to the action of the air or steam
or both substantially as hereinbefore described and adding ore and finishing the
charge in the ordinary way.
Dated this 2nd day of April 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.