Checkering Bricks for Hot Blast Stoves.
Year: 1898

page_text: Date of Application, 29th Aug., 1898-Accepted, 29th Oct., 1898
COMPLETE SPECIFICATION.
Checkering Bricks for Hot Blast Stoves.
I, JOHN LESTER STEVENSON, of Cleveland Steel Works, South Bank. R.S.O., in
the County of York, Engineer, and JOHN EVANS, of Cleveland House, South
Bank, in the County of York, Engineer Student, do hereby declare the nature
of this invention, and in what manner the same is to be performed, to be par-
ticularly described and ascertained in and by the following statement; -
This invention relates to improvements in bricks designed to form the heating
bodies in hot blast stoves of the type now commonly used for heating the blast
prior to its admission to a blast furnace, a reverbarotory furnace or for any
analogous purpose.
"
The object of this invention is to provide a form of brick which it shall be
possible to lay in horizontal layers and in such manner that the joints between
the bricks of any layer will break joint" with the bricks in the layers next
above and below it. This is a result not heretofore possible with any form of
brick now known to the art.
The necessity of having a strong structure and one securely bound together
is rendered obvious when it is considered that hot blast stoves are cleaned by
exploding a suitable detonating substance in the chamber below the brickwork,
the explosion loosening the dust accumulated in the flues and causing it to fall
into the chamber below.
Another advantage arising from the use of this improved form of bricks is
that the use of small pieces, in breaking joints and for filling round the sides
of the stoves, is avoided thus obviating the choking of the flues by the small
pieces becoming loosened and falling into them, and the consequent loosening
of the whole wall.
The invention consists then, in the peculiar form and construction of the
brick used; the same consisting of a longitudinal portion or shank, having
opposite lateral projections at or near the ends thereof, and so arranged relatively
to the shank, that the brick may be laid in such manner that bricks in adjacent
layers may be disposed in varying positions with relation to each other, and thus
secure the desired overlapping of the individual bricks.
In the accompanying drawings, forms of bricks are shown fully illustrating
and setting forth this invention.
In Figures 1 to 6 the brick shown as embodying our invention consists of a
main portion or shank, having lateral projections a, arranged on both sides
thereof so as to form with said shank symmetrical double crosses. The lateral
projections of the brick forming the transverse pieces of the cross, are equal in
length to each other and also to the length of the projection of the longitudinal
part of the cross at either end beyond the transverse part adjacent to that end,
and the distance between the transverse pieces is twice as great as the length
of the projections. It is obvious that bricks of this form placed together in
the same plane and several layers of bricks being laid one on top of the other,
n the manner shown in Figs. 1 and 2, of the drawings, will form vertically con-

page_text: tinuous square flues. The size of the bricks may be varied in any case, but the
preferable size will be such that a flue of from seven to nine inches will be
formed.
It is evident that when the bricks are laid, as shown in Fig. 3, the proportion
of the lateral and transverse parts must be such as will form a square flue in
case flues continuous from top to bottom are desired. If, however, the bricks are
laid as shown in Fig. 2, the longitudinal parts thereof all extending one way,
the length of the lateral projections relative to the length of the longitudinal
portion of the brick may be such that the flue formed will be larger in one
direction than the other instead of being square, without departing at all from
the principle of the invention. Bricks adapted to form square flues are, however,
considered the preferable form, as by using that form it is possible to break joints
in both directions, thus forming a stronger and firmer wall. Nor is it the in-
tention to limit the projections to any particular number, as they may be multi-
plied as desired and the principle of the invention still retained.
A modified form of the brick shown in Figs. 4, 5, and 6 is shown in Fig. 7
of the drawings, the top and bottom edges of the longitudinal part being
bevelled, as shown at A2.
This form of brick is intended for use, principally when in place of small square
or rectangular, unobstructed and continuous flues, it is desired to form a struc-
ture which will be divided throughout by parallel walls extending continuously
from top to bottom thereof and separated by open spaces. In this form of structure
the bricks are so laid that the lateral projections thereof will form the walls;
the longitudinal portions extending across the open spaces between the walls
in such manner that said longitudinal portions of the bricks of any layer will
be over the middle of the spaces between the similar parts of the bricks in the
layers next above and below it. By this form of construction, the passage of
the gases and also of the blast through the stove, will be divided and will circulate
among the bricks forming the structure, as to insure thorough mixing of heat
and blast. The edges of the bricks, against which the air and gases strike, are
bevelled so that they will offer less resistance to the passage thereof, and will
not present any horizontal surfaces to receive and retain dust or soot."
The use of small pieces in the wall is avoided with this brick, by turning it in
such a manner that the longest or shortest way of the brick is used as may be
required.
The form of bricks herein shown and described, to wit, that shown in Figs. 1
to 6 obviously possess in common the feature of similar lateral projections at both
ends, which, when the bricks are laid in a manner to form continuous vertical
flues, constitute, (with the middle part or body of the brick) the walls of the
flues, and which, by reason of the similar shape at both ends overlapping, or
so as to "break joints" as hereintofore described, when the lateral projections
are at right angles to the body, as seen in Figures 3, 4, 5, and 6.
The form of brick having lateral projections at right angles to the body thereof,
is of special advantage for building square flues or for building open structures
such as are shown in Figs. 8 and 9 and this particular form being in itself novel
is also herein claimed as part of our invention.
These bricks are specially designed for checkering stoves in such a manner
that no half holes or small holes are left except round a small portion of the
lining as shown in Figure 2, which cannot be done with any brick at present
used for the same purpose.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that
what we claim is:-
1. A brick for the purpose described, provided on each side with two lateral
projections arranged at right angles to the body of the brick at points midway
between the middle and the ends of the same substantially as described.

page_text: 2. A brick for the purpose described, provided with lateral projections arranged
at right angles to the body of the brick at points distant from its ends, the
length of the said lateral projections being equal to the distance from the same to
the ends of the brick substantially as described.
3. A brick for the purpose described provided with lateral projections at its ends
arranged at right angles to the main part or body of the brick, the length of said
projections at its ends arranged at right angles to the main part or body of the
brick, the length of said projections being equal to the distance of said projec-
tions from the ends of the brick, and the distance between the projections being
equal to twice their length, substantially as described.
Dated this Sixteenth day of August in the year of our Lord One thousand
eight hundred and ninety eight.