An Improvement in Feed Apparatus for Blast Furnaces.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
An Improvement in Feed Apparatus for Blast Furnaces.
We, BENJAMIN HOWARTHI THWAITE, of 29, George Street, Westminster, in the
County of London, Civil Engineer, and FRANK LACROIX GARDNER, of 32, Old
Jewry, in the City of London, Mining Engineer, do hereby declare the nature of
this invention to be as follows:-
The gases discharged from the top of a blast furnace, being more or less com-
bustible, are often utilised for heating purposes and sometimes for operating in
gas engines, but in the act of feeding the furnace with air, fuel and flux, there
is a considerable loss by escape of these gases.
Our invention relates to means of preventing this loss, which we effect as
follows. Above the chamber surrounding the cone, which constitutes the feeding
valve, we provide a vertically movable cover which has at its edge a flange dipping
into a circular sand trough. This cover being raised, the feeding charge is
lodged in the space over the cone which is then in its raised position closing the
top of the furnace.
The cover is then lowered so that its flange is immersed in the sand making
a practically gas tight joint.
The cone is then lowered allowing the charge to drop into the furnace.
As often as feeding is required this operation is repeated.
Thus, as the cone is not down when the cover is up, and as the cover is down
when the cone is lowered, there is no sensible escape of gas during the feeding
operation.
Ta 1000
An Improvement in Feed Apparatus for Blast Furnaces.
We, BENJAMIN HOWARTHI THWAITE, of 29, Great George Street, Westminster,
in the County of London, Civil Engineer, and FRANK LACROIX GARDNER, of
32, Old Jewry, in the City of London, Mining 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:-
The gases discharged from the top of a blast furnace, being more or less com-
bustible, are often utilised for heating purposes, and sometimes for operating in
gas engines, but in the act of feeding the furnace with air, fuel and flux, there is
a considerable loss by escape of these gases.

page_text: Our invention relates to means of preventing this loss, which we effect as
shewn in section in the accompanying drawing. Above the chamber surrounding
the cone A which constitutes the feeding valve of the furnace we provide a
vertically moveable cover B which has at its edge a flange C dipping into a
circular sand trough.
This cover being raised as indicated by the dotted lines B1, the feeding charge
is lodged in the space over the cone A, which is then in its raised position closing
the top of the furnace.
The cover B is then lowered so that its flange is immersed in the sand,
making a practically gas tight joint. The cone A is then lowered allowing the
charge to drop into the furnace. As often as feeding is required this operation
is repeated.
Thus, as the cone is not down when the cover is up, and as the cover is down
when the cone is lowered, there is no sensible escape of gas during the feeding
operation.
Flaps D hinged over holes in the cover B serve as safety valves allowing escape
of gas should the pressure under the cover greatly exceed the external pressure.
The cover B as it is raised and lowered is guided by the rod E from which the
cover A is suspended.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:-
In combination with the feed valve of a blast furnace, a vertically moveable
cover constructed and operating substantially as and for the purpose set forth.
Dated this 22nd day of October 1898.
ABEL & IMRAY,
Agents for the Applicants.