Furnaces for Heating Steel Ingots.
Year: 1893

page_text: Date of Application, 3rd Jan., 1893-Accepted, 4th Feb., 1893
COMPLETE SPECIFICATION.
Furnaces for Heating Steel Ingots.
I, WALTER EDWARD KOCH, of 110 Diamond Street, Pittsburgh in the County
of Allegheny, and State of Pennsylvania, United States of America, Gentleman,
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 my invention is to provide a furnace for heating steel ingots in
which the ingots may be acted upon in a continuous operation and in which the
maximum amount of the surface of the ingot will be exposed to the action of the
heat while all cooling drafts will be prevented.
This object I accomplish by the use of a furnace constructed as illustrated in
the accompanying drawings and the invention consists in certain novel features of
the same as will be hereinafter first fully described and then pointed out in the
claims.
Heretofore, steel ingots have been heated in one of two ways, either by being
placed on their sides in heating furnaces or by being placed erect on end in pits,
both of which methods produce unsatisfactory results and require much handling
and many furnaces. In the horizontal position only three sides are presented to
the flame, the fourth side receiving heat only from the furnace bottom or by turning
over the ingots, hence the ingot is unevenly heated and proper treatment in the
rolling mill is rendered impossible. In the vertical position the top of the ingot
is liable to be heated to a greater degree than the bottom or thicker end and this
uneven heating also gives trouble in the rolling process. Moreover, in both these
methods there is incurred an expense in handling and an unnecessary waste in
cinder caused by undue heating of one part of the ingot and by impinging currents
of air through the furnace doors. Furthermore, so far as I am aware, no furnace
has been heretofore produced which would operate continuously, the ingots being
either taken out singly and another ingot slipped into the vacant place or the entire
heat of ingots is taken from the furnace and the furnace then re-charged. This
operation is objectionable for the reason that the ingot is suddenly put into a very
hot place and the steel frequently injured by too sudden expansion.
In the furnace designed by me, the ingots are acted upon in a continuous operation
and are gradually heated while the maximum amount of their surfaces is exposed
to the direct action of the heat; moreover I can heat the ingot just when and
where required and I consequently overcome all the objections heretofore found
to exist.
In the accompanying drawings, which fully illustrate my invention,
Fig. 1 is a horizontal section taken on the line x-x of Fig. 2;
Fig. 2 is a vertical longitudinal section taken on the line y-y of Fig. 1;
Fig. 3 is a transverse section on the line - of Fig. 1 and
Fig. 4 is an end elevation.
form.
In carrying out my invention, I employ a furnace 2 which may be of any desired
In the drawings I have illustrated a form of the Siemen's furnace provided
with regenerative chambers 9. This furnace is provided with the central depressed
floor 18 having a central longitudinal slot 17 and inclined from said slot towards
each side. Doors 6 and 7 are provided at the ends of the furnace and separate the
same from the ante-chamber 3 and the post-chamber 4, as clearly shown. The said
chambers 3, 4 are provided with doors 5 and 8, as shown, so that all detrimental
air drafts will be cut off.
Extending through the furnace, below the floor of the same, is a track 10 which
also extends through the chambers 3, 4 and beyond the ends thereof. An endless

page_text: chain 11 runs between the rails of the said track and in a recess prepared therefor
in the foundation of the furnace. This belt or chain is driven by sprocket wheels 12
and gearing 13 in the direction indicated by the arrows in Fig. 2. Riding upon
the track 10 is a series of cars 14 which are connected together by links and pins
or any other readily detachable means and connected with the endless chain by a
link 15.so that as the chain moves the cars will be drawn through the furnace. It
will be understood, of course, that a number of the links 15 are provided and that
as the cars leave the furnace and are discharged of their loads they are run upon
the tracks 10 back to the entrance of the furnace to be again passed through the
same. These cars 14 are provided with narrow standards which project up through
the slot 17 and support small tables or slabs 16 which are faced with fire-clay,
In practice, the ingot or bloom 19 is taken from the casting pit or mold by
suitable mechanism and placed on the front car. The gearing is then permitted to
move the car a distance sufficient to carry the bloom or ingot into the ante-
chamber 3. A second bloom is then placed on the succeeding carriage or car and
the doors 5 and 6 opened to permit the passage of the two ingots into the ante-
chamber and the cooler portion of the furnace, respectively. This operation is
repeated until the entire quantity of ingots has been passed through the furnace.
As each ingot leaves the furnace it is fed into the rolling mill as will be readily
understood.
From the foregoing description, taken in connection with the accompanying
drawings, it will be seen that I have provided a furnace in which the ingots will
be continuously fed into the furnace and will be passed through the same so as to
be gradually heated. It will be observed that the ingot first passes into the ante-
chamber and that the doors of the same are closed so as to prevent the access of air
to the furnace and that after the ingot enters the furnace it is not at once subjected
to an intense heat but enters the furnace at a point remote from the source of heat
and is moved gradually toward the heat and is not subjected to the most intense
heat until it reaches a point between the regenerative chambers 9, by which time
its temperature will have been raised. It will furthermore be noticed that the butt
end of the ingot can be heated as thoroughly as the top and that the whole ingot
or bloom will be evenly heated and delivered to the rolling mill in the best possible
condition for treatment. The doors effectually prevent the entrance of detrimental
air drafts and hence cinder and loss will be reduced to a minimum.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1. The combination with a furnace for heating ingots, provided with a central
longitudinal slot in its floor, of a series of cars arranged below the floor and adapted
to move through the furnace and provided with standards projecting through the
said slot and carrying the ingots above the floor, and mechanism for moving the
said cars continuously through the furnace.
2. The combination with a furnace having its floor provided with a central
longitudinal slot and inclined from said slot towards the sides, of a series of cars
arranged below the floor and having standards projecting through the slot and
provided with means above the floor for carrying the ingots.
3. The combination with the furnace having a slotted floor, of a track running
through the furnace below the said floor, an endless chain moving between the rails
of the said track, a series of cars mounted on the track and connected with said
endless chain and having standards projecting through the slot in the floor, and
means for moving the endless chain.
Dated this 6th day of December 1892.
WALTER EDWARD KOCH.