IMPROVEMENTS IN WATER GRATES OR HEARTHS FOR STEAM BOILER AND OTHER FURNACES
Year: 1878

page_text: LETTERS PATENT to George Green, William Alfred Green, and James George
Green, of Aberystwith, in the County of Cardigan, Engineers, for the Inven-
tion of "IMPROVEMENTS IN WATER GRATES OR HEARTHS FOR STEAM BOILER
AND OTHER FURNACES."
Sealed the 29th October 1878, and dated the 10th May 1878.
PROVISIONAL SPECIFICATION left by the said George Green, William
Alfred Green, and James George Green at the Office of the Commissioners of
Patents on the 10th May 1878.
GEORGE GREEN, WILLIAM ALFRED GREEN, and JAMES GEORGE GREEN, of Aberyst-
with, in the County of Cardigan, Engineers. "IMPROVEMENTS IN WATER GRATES
OR HEARTHS FOR STEAM BOILER AND OTHER FURNACES."
This Invention relates to water grates or hearths for steam boiler and other
furnaces, and consists in making and arranging them in an improved manner
herein-after described, so as to secure the advantages of such grates without the
defects which have prevented the general use of those hitherto tried.
A modification of the improved grate suitable for the internal furnace of a steam
boiler consists of a shallow box formed by upper and lower horizontal plates of
wrought iron or steel, or copper, connected by narrow sides and ends with angle
iron at the joints, or with welded joints. Or the sides and ends may be made of
channel iron and be directly rivetted to the top and bottom plates.
Holes are formed in the top and bottom plates of the grate box, and in these
holes are fixed short vertical tubes of copper, or iron, or steel, which tubes are by
preference tapered, their bottom ends being larger, so that ashes may fall freely
down through them whilst air passes up through them to the fuel.
The water is admitted to one or more parts of the improved grate box by a pipe

page_text: or pipes connecting it to the lower part of the boiler, whilst one or more other
pipes connect another part of the grate box to a higher part of the boiler.
The improved water grate herein-before described, or the tubes, may be made of
brass or other suitable metal instead of any of the metals herein-before named.
-
SPECIFICATION in pursuance of the conditions of the Letter's Patent filed by
the said George Green, William Alfred Green, and James George Green in the
Great Seal Patent Office on the 9th November 1878.
GEORGE GREEN, WILLIAM ALFRED GREEN, and JAMES GEORGE GREEN, of Aberyst-
with, in the County of Cardigan, Engineers. "IMPROVEMENTS IN WATER GRATES
OR HEARTHS FOR STEAM BOILER AND, OTHER FURNACES."
Our said Invention relates to water-grates or hearths for steam boiler and other
furnaces, and consists in making and arranging them in an improved manner herein-
after described, so as to secure the advantages of such grates without the defects
which have prevented the general use of those hitherto tried.
A modification of our improved water-grate suitable for the internal furnace of a
steam boiler consists of a shallow box formed by upper and lower horizontal plates
of wrought iron, or steel, or copper, or brass, or other suitable metal, connected by
narrow sides and ends.
Holes are formed in the top and bottom plates of the grate box, and in these holes
are fixed short vertical tubes of copper, or iron, or steel, or brass, or other suitable
metal, which tubes are by preferenco tapered, their bottom ends being larger, so that
ashes may fall freely down through them whilst air passes up through them to
the fuel.
The water is admitted to one or more parts of our improved grate box by a pipe
or pipes connecting it to the lower part of the boiler, whilst one or more other pipes
connect another part of the grate box to a higher part of the boiler.
And in order that our said Invention, and the manner of performing the same
may be properly understood, we hereunto append a Sheet of explanatory Drawings
to be herein-after referred to, and representing our improved water-grate or hearth,
as fitted to the internal furnace of a horizontal cylindrical steam boiler.
In these Drawings the same reference numerals are used to mark the same or
like parts wherever they are repeated.
Figure 1 on the accompanying Sheet of Drawings is a plan of our improved water
grate or hearth; and Figures 2 and 3 are longitudinal and transverse vertical
sections of part of a steam boiler fitted with the water-grate or hearth.
Our water-grate is formed with top and bottom plates 1, 2, rivetted to the upper
and under sides of a frame 3 so as to form a shallow box, the frame 3 forming the
ends and sides.

page_text: A number of holes are formed in the top and bottom plates 1, 2, and in these,
short taper tubes 4, having their larger ends below, are fixed by expanding or rivet-*
ting, or screwing, or screwing and rivetting combined.
The grate box is connected by four pipes to the boiler, two, 5, of these forming
communications with the lower part of the boiler, and the other two, 6, being con-
nected to the upper part of the boiler.
The upper connecting pipes, 6, are by preference fixed to the grate box near one
ond of it, whilst the lower connecting pipes, 5, are fixed to its other end; and this
arrangement will have the effect of causing the water to circulate vigorously through
the connecting pipes and through the grate box itself.
The grate box is by preference placed with a slight inclination, as shown in
Figures 2 and 3, but it may be horizontal or otherwise inclined if preferred.
The top and bottom plates 1, 2, may be connected in various ways, as for example,
by channel iron or by angle iron, and a narrow plate or plates forming the ends
or sides, or the top and bottom plates 1, 2, may be flanged at their edges and bo
directly rivetted or welded to each other, or to a narrow plate or plates.
The grate box is, in the accompanying Drawings, shown of an oblong rectangular
form in plan, but it can be made of any other shape to suit the form of furnace to
which it is applied. It can be used with advantage in any furnace in which ordi-
nary grate-bars are commonly used, and when the furnace is not that of a steam
boiler the grate box may be connected to a cistern or tank of water, so that there
may be a circulation of water through it.
The presence of the water in the grate box prevents the over-hoating which
causes the rapid destruction of ordinary grate-bars and their want of durability,
and in the case of steam boilers the water-grate constitutes a very efficient supple-
mentary heating surface, and its use effects considerable economy of fuel as com-
pared with ordinary furnace grates.
Having thus particularly described our said Invention, and the manner of per-
forming the same, we have to state that we do not restrict ourselves to tho
precise details heroin described or delineated, but that what we believe to be novel
and original, and claim as the Invention secured to us by and in terms of the
herein-before in part recited Letters Patent is, the constructing of water-grates or
hearths for steam boiler and other furnaces in the improved manner herein described,
and as shown on the accompanying Drawings.
In witness whereof, I, the said William Alfred Green (on behalf of the said
George Green and James George Green, and for myself) have hereunto set
my hand and seal, this Eighth day of November, in the year of our Lord
One thousand eight hundred and seventy-eight.
WILLIAM ALFRED GREEN. (L.S.)