Improvements in Open Hearth Furnaces.
Year: 1888

page_text: Improvements in Open Hearth Furnaces.
I, FREDERICK SIEMENS, of No. 12 Queen Annes Gate, Westminster, in the County
of Middlesex, 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 my Specification No. 6633 of 1885 I describe a construction of furnace having
its superstructure supported independently of the bed, so that the upper zone of the
bed lining is accessible from outside, and can be readily repaired or renewed without
interfering with the general structure or only slightly with the working of the
furnace.
My present invention relates to means, of arranging such a removeable zone in
connection with various forms of furnaces at various parts of their structure, such
arrangements being particularly applicable when a bed of basic or alkaline material
has to be separated from a superstructure of silicious or acid character, by a zone of
neutral material such as bauxite, carbon, chrome-iron-ore and the like, such material
being cut into shape or rammed into place or formed in bricks or blocks with binding
material if necessary.
In the accompanying drawings the same letters of reference are employed as far as
possible to indicate corresponding parts.
A is the arched roof of the furnace; B is the side wall carrying the roof or the
haunch of the arch when no such wall is used; C is the plate or angle base which
carries the superstructure; N is the bed, D the casing of the bed and G is the
removable zone interposed between N and B. As shewn in the part section Fig. 1,
the angle base C is carried on struts ✗ supported on a flange of the bed casing D, the
removable zone G, which may consist of several layers being accessible from outside
between the struts X, which are themselves removable, temporary supports being
substituted. Fig. 1 is a part section shewing the construction where a working
door occurs and Fig. 1B shews the construction where the gas, air and flame ports
occur, these ports being carried on a plate Q forming a bridge, beneath which there is
sufficient room to give free access to the zone G. Fig. 1° shews the construction

page_text: where a tapping hole occurs. As shewn in Figs. 2, 3 and 4 the base plate Cis
supported on columns T, which may have ribs bearing against and supporting the sides
of the bed.
The removable zone G which may be of rectangular section as in Fig. 3, or wedge
shaped as in Fig. 4, may be kept in place by removable plates E held in position by
bars resting against the columns T or otherwise. In Figs. 5, 6 and 7 the plate Q
which carries the ports P is supported on brackets R bolted to the casing of the bed.
In cases where it is necessary to construct the flame ports at a level higher than
usual in order to provide for access to the removable zone beneath them, or in cases
where the bed is deeper than usual, I incline the ports somewhat downwards towards
the bed so that the live flame may travel near to, but without touching the metal under
treatment. Thus, while preserving heating by radiation the flame may be kept as
close as possible to the metal.
As shewn in Figs. 8 and 9 the removable zone may be made in two parts, one of
which G occupies part of the bed at its upper edge. Fig. 10 is a part section, and
Fig. 11 a part plan shewing a layer G2 of neutral material interposed between the
upper edge of the bed and the mouth of the port P, this layer G² being accessible at
each end, through openings O.
Having now particularly described and ascertained the nature of this invention and
in what manner the same is to be performed, I declare that what I claim is :-
In an open hearth furnace having its roof supported independently of the bed, the
use of a removable zone of neutral material interposed between the bed and the super-
structure, arranged in such a manner as to be accessible from outside, substantially as
herein described and illustrated by the accompanying drawings.
Dated this 16th day of August 1888
ABEL & IMRAY,
Agents for the Applicant.