Improvements in the Construction of Dampers, Furnace Doors and similar Devices.
Year: 1898

page_text: Date of Application, 11th Nov., 1898
Complete Specification Left, 31st Aug., 1899-Accepted, 14th Oct., 1899
PRUVIDIUNAL SIECIFICATION.
Improvements in the Construction of Dampers, Furnace Doors and
similar Devices.
We, ALFRED JOHN LIVERSEDGE, Engineer, and BEAMAN & DEAS LIMITED,
Engineers, both of 32, Victoria Street, Westminster, in the County of London,
do hereby declare the nature of this invention to be as follows:
Our invention relates to the construction of dampers, furnace doors and similar
devices that are exposed to the action of flame, radiated heat, or high temperature
gases. Such dampers and doors have hitherto been generally made of plates of
iron or steel or of large slabs of fireclay, or of firebrick or blocks built into
iron frames. These constructions are however all found objectionable, because
if made of metal the dampers or doors are liable to warp and bend; or if made of
fireclay slabs they are liable to break and fall in pieces from unequal expansion
or contraction; or if made of firebricks or blocks built in the ordinary way into
iron frames, the bricks or blocks are liable to become loosened and drop out.
Now our improvements consist in constructing the dampers or doors of tiles
or slabs composed of fireclay or other refractory material held together and in
position by iron or other rods passing through perforations or passages in the
tiles or slabs. Preferably the perforations through the tiles are parallel with
the plane of the damper or door, and are located approximately midway of the
thickness of the tiles, so that the holding rods are surrounded by a sufficient
thickness of the refractory material to protect them from the direct action of
the heat. The said holding rods may be rivetted or otherwise secured to cross
bars forming part of the damper or door; or in the case of dampers that have to
present either face to the flame or hot gases, the holding rods may be fitted
more or less loosely into a metal hoop, frame or skeleton. In the case of
furnace doors that have to present only one face to the source of heat, the said
holding rods may be fitted in any convenient manner into a metal frame, box
or case. In order to minimize the leakage of air or gas through the damper
or door, the tiles of refractory material may have their edges so formed that
when the said tiles are put together their edges will interlock the one with
the other; for instance they may be grooved and tongued so that their edges
more or less dovetail into each other. Also in order to more effectually protect
the aforesaid holding rods from becoming distorted by the action of the heat,
the perforations through which they pass may be made large relatively to the
thickness of the rods themselves and the space thus formed around the rods
and between them and the tiles, may be packed with slag wool or other non-
conducting substance. It will be readily understood that by building dampers
and doors in the manner described, the disposition of the tiles or slabs will
enable them to lie quite loose relatively to each other and to the frame carrying
them and as they are retained in their places by the aforesaid holding rods,
we thus provide for very considerable expansion taking place without risk of the
tiles falling out from the dampers or doors.

page_text: It will be obvious that the details of the construction of our improved dampers,
doors and similar devices can be considerably varied in accordance with the
particular purposes they are required to fulfil, without departing from the nature
of our invention.
Improvements in the Construction of Dampers, Furnace Doors and
similar Devices.
We, ALFRED JOHN LIVERSEDGE, Engineer, and BEAMAN & DEAS LIMITED,
Engineers, both of 32, Victoria Street, Westminster, in the County of London,
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:―
Our invention relates to the construction of dampers, furnace doors and similar
devices that are exposed to the action of flame, radiated heat or high temperature
gases. Such dampers and doors have hitherto been generally made of plates of
iron or steel, or of large slabs of fireclay, or of fire bricks or blocks built into
iron frames. These constructions are however all found objectionable, because
if made of metal the dampers or doors are liable to warp and bend; or if made
of fireclay slabs they are liable to break and fall in pieces from unequal expansion
or contraction; or if made of firebricks or blocks built in the ordinary way into
iron frames, the bricks or blocks are liable to become loosened and to drop out.
Our improvements consist in constructing the dampers or doors of tiles or
slabs composed of fire clay or other refractory material held together and in
position within a frame by rods passing through perforations or passages in
the tiles or slabs. Preferably the said perforations or passages are parallel
with the plane of the damper or door, and are so arranged that the holding
rods are surrounded by a sufficient thickness of the refractory material to protect
them from the direct action of the heat.
It will be readily understood that by constructing dampers and doors in the
manner described, the disposition of the tiles or slabs will enable them to lie
quite loose relatively to each other and to the frame carrying them and as they
are retained in their places by the aforesaid holding rods, we thus provide for
very considerable expansion taking place without risk of the tiles falling out
from the dampers or doors.
In order that our said invention may be clearly understood and readily carried
into effect we will proceed to describe the same more fully with reference to the
accompanying drawings in which:-
:-
Figure 1 is a transverse section of a flue provided with a damper constructed
in accordance with our invention.
Figure 2 is a horizontal section on the line 1-1 of Figure 1, and
Figure 3 is a vertical section on the line 2-2 of Figure 1.
Figure 4 is an elevation of a fire resisting door constructed in accordance
with our invention and employed for closing an opening in a flue.
Figure 5 is a transverse section of the same on the line 3-3 of Figure 4 and
Figure 6 is a vertical section on the line 4 4 of Figure 4.
Figure 7 is a transverse section showing a modification.
A A are the tiles or slabs of fireclay or other refractory material. B B are the

page_text: iron or other rods by which such tiles or slabs are held in place within the
frame C.
Referring more particularly to Figures 1, 2 and 3 the frame C of the damper
here illustrated consists of a marginal portion preferably of wrought iron or
steel with two transverse stiffening pieces c c riveted or otherwise connected to
the said marginal portion. The lower portion of the frame is provided with a
pivot cresting in a cast iron shoe d embedded in the floor of the flue D. The
upper portion of the frame is provided with a spindle extending through a
stuffing box built in the crown of the flue and provided at its outer end
with a square or rectangular portion to receive an arm or other contrivance for
opening and closing the damper. The aforesaid tiles A are arranged within
the said frame as illustrated in the drawings, each of the said tiles being pro-
vided with vertical perforations or passages a, which when the tiles are in place
form vertical rows of passages for the reception of the aforesaid rods B. These
rods rest at their lower ends in recesses in the bottom part of the aforesaid
frame and pass through perforations formed in the transverse stiffening members c
and in the upper part of the aforesaid frame. The rods fit only loosely in the
perforations in the tiles and in the frame in order that some amount of play may
be left to provide for expansion and contraction due to the differences in tem-
perature to which the damper is subjected. The lower ends of the said rods
are however tightly fitted in the frame. On reference to Figure 2 it will be
observed that the said tiles are enlarged or thickened at the parts where the
aforesaid perforations are formed through them, so that the perforations may be
made sufficiently large to loosely receive the rods B. If the tiles be made of equal
thickness throughout, as represented in Figure 5, it will or course be obvious that
the aforesaid enlarged or thickened portions will be unnecessary; but where it is
desired to obtain lightness we prefer to make the tiles in the manner represented
in Figure 2.
In the arrangement illustrated by Figures 4, 5 and 6 we have shown the tiles
applied to a fire resisting door employed for closing an opening into a flue. In
this case the top and bottom marginal portions C of the door are composed of
angle-irons riveted or otherwise connected to the door-plate E. The aforesaid
rods B extend through the tiles A as in the previous example and rest at their
lower ends in recesses in the bottom angle-iron while their upper ends extend
through perforations in the upper angle-iron; the said rods being fitted in place
as in the previous example, for the purpose already stated. In the construction
illustrated we have provided an air space E' between the inner surface of the
door-plate E and the inner surface of the tiles. This space may however be
packed with slag-wool, asbestos or other heat non-conducting material, so as to
further protect the door-plate from the hot gases passing contiguous thereto.
It will be obvious that the details of construction of our improved dampers and
fire-doors may be modified to suit special requirements. For example we may
make the damper double, that is to say, with two sets of tiles arranged on opposite
sides of a metal plate situated between them. The meeting edges of the tiles may
be so formed that they will interlock the one with the other or overlap so as to
minimize the leakage of air or gas through the damper or door; for instance
they may be formed as represented in Figure 7. In order to more effectually
protect the said holding rods B from the action of the heat, the perforations or
passages through which they pass may be made large relatively to the thickness
of the rods themselves and the space thus formed around the rods may be packed
with some suitable heat non-conducting substance such as that employed in the
air space E¹.
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
T
"
2

page_text: slabs held together within a frame or other support by rods passing loosely through
perforations or passages in the said tiles or slabs for the purpose specified.
2. A damper constructed substantially as described with reference to Figures 1,
2 and 3 of the accompanying drawings for the purpose specified.
3. A fire-door constructed substantially as described with reference to Figures 4,
5 and 6 of the accompanying drawings for the purpose specified.
Dated this 31st day of August 1899.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.