IMPROVEMENTS IN REGENE- RATIVE STOVES FOR HEATING THE BLAST FOR BLAST FURNACES
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Benjamin Ford at the Office of the
Commissioners of Patents on the 5th June 1882.
BENJAMIN FORD, Engineer, Middlesbro on Tees, "IMPROVEMENTS IN REGENE-
RATIVE STOVES FOR HEATING THE BLAST FOR BLAST FURNACES,"
In Regenerative Stoves for heating the Blast for Blast Furnaces, their heating
power is interfered with and becomes inefficient from a nonconducting material
carried into them by the Gas, and which is deposited on their heating surfaces
during its combustion, while the stove is being heated, this deposit therefore
requires to be removed from time to time.
Various methods have been adopted for the removal of this deposit, that most
generally used is to arrange the flues and interstices in the interior of the stove,
so that by openings in the casing, scrapers, wire brushes, or other apparatus can
be passed through and reach the heating surfaces of these flues or interstices, and
thereby remove the deposit; these openings in the casing being afterwards closed
by air tight doors or valves.
This method of cleaning being incovenient and requiring much labour, also
stopping the work of the stove for some time, is only used as seldom as possible,
so that the deposit is allowed to accumulate, and by the pressure of the blast it
cakes and adheres firmly to the heating surfaces, and where the deposit contains
much lime the intense heat causes it to fuse so that the deposit is very difficult to
remove; the stove is therefore seldom efficiently cleaned by this method. Another
plan is used to detach this deposit, viz:-exploding charges of gun powder or other
explosive, in the upper or lower parts of the stove, which method is also attended
with inconvenience.
To understand my improvements it is necessary to explain that while the Blast
is passing through one stove that has already been heated, another stove is being
heated preparatory to being used in its turn, when the temperature of the other
has been sufficiently reduced: so that these stoves have to be changed from Blast
to Gas alternately.
In changing a stove from Blast to Gas, it is necessary to shut the communication
with the Blast Furnace, and also the valve through which the air to be heated

page_text: passes into the stove, thereby shutting up the whole of the air contained in the
stove. It is therefore obvious that before a stove can be again put on gas, this
enclosed air must be discharged and is under a pressure equal to that required in
blowing the furnace.
Now my improvements consist in making this confined air in its discharge clear
the deposit from the heating surfaces. This is accomplished by dividing the
interior of the stove into several compartments communicating with each other.
On the casing of the stove and in connection with each of these compartments
separately, I place air-tight doors or valves which can be opened rapidly or instan-
taneously by removing a catch or detent or such valves may revolve on an axis so
as to cause the whole of the enclosed air contained in the stove to be discharged
through one particular compartment and instantaneous or rapidly opening the door
or valve connected with it. The air being thus confined in its passage has sufficient
velocity and force to detach and carry off the deposit from that compartment where
the door or valve has been opened, and as this discharge takes place in one or other
of these compartments at every change from Blast to Gas, the deposit is never
allowed to accumulate and thus the stove is kept clean and efficient.
In some arrangement of stove I also connect each of the above compartments,
into which I divide the stove, separately to the chimney flue, and which connections
or communications can be closed or opened by means of doors or valves that can be
actuated from the outside of the stove.