Improvements in Steam-boiler and other Furnaces.
Year: 1888

page_text: Date of Application, 10th May, 1888
Complete Specification Left, 1st Jan., 1889
Complete Specification Accepted. 5th Feb., 18
PROVISIONAL SPECIFICATION.
Improvements in Steam-boiler and other Furnaces.
I, JAMES HUNTER ANNANDALE, of Polton Paper Works, Polton, in the ('ounty of
Mid Lothian, North Britain, Paper Maker, do hereby declare, the nature of this Inven-
tion to be as follows, that is to say:
My said Invention has for its object by an improved construction of steam-boiler
and other furnaces, to secure a large saving in fuel as compared with many existing
furnaces, to prevent smoke, and to very completely exhaust the combustible con-
stituents of the fuel. The improved arrangements are also such as to diminish labor,
and exposure of the stokers to extremes of heat and cold, whilst avoiding as much as
possible injurious action on the boiler from the admission of chilling air currents.
In carrying out my Invention I form at the inner end of each furnace a rectangular
opening in which I fit a frame carrying a perforated hearth slab or a grating, and
mounted so that it can be turned about a longitudinal or transverse axis into a vertical
position. In a convenient inodification the movable frame is carried by a longitudinal
spindle or shaft supported by the bridge and by the inner bearer of the fire bars,
and extending out to the front of the furnace. A lever is fixed on the front end of
the shaft, and suitable catches are provided for securing it with the frame either in a
horizontal or vertical position.
In working with the improved apparatus the fuel is by preference heaped up at the
front ends of the fire bars and is gradually pushed inwards until it reaches the movable
frame. When the residue of the fuel at any time upon the movable frame is considered
to be sufficiently exhausted, the frame is turned up to drop it into the ashpit below from
which pit the ashes or residue can be removed at any convenient time. The frame is
next turned back to its horizontal position and the fuel on the bars is pushed inwards
so that a portion of it may be moved on to the frame.
Along with the improved apparatus hereinbefore described I prefer to use a hollow
bridge into which is led air heated by passing through pipes arranged in portions of
the flues, the hollow bridge being made with orifices through which the air issues
amongst the gases passing from the furnace with the effect of preventing smoke by
further promoting complete combustion.
Dated this Ninth day of May 1888.
EDMUND HUNT,
Applicant's Agent.

page_text: COMPLETE SPECIFICATION.
Improvements in Steam-boiler and other Furnaces.
JAMES HUNTER ANNANDALE, of Polton Paper Works, Polton, in the County of
Mid Lothian, North Britain, Paper Maker, 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, that is to say:
-
My said Invention has for its object by an improved construction of steam-boiler
and other furnaces, to secure a large saving in fuel as compared with many
existing furnaces, to prevent smoke, and to very completely exhaust the combustible
constituents of the fuel. The improved arrangements are also such as to diminish
labor, and exposure of the stokers to extremes of heat and cold, whilst avoiding as much
as possible injurious action on the boiler from the admission of chilling air currents.
In carrying out my Invention I form at the inner end of each furnace a rectangular
opening in which I fit a frame carrying a perforated hearth slab or a grating, and
mounted so that it can be turned about a longitudinal or transverse axis into a vertical
or inclined position.
In working with the improved apparatus the fuel is by preference heaped up at the
front ends of the fire bars, and is gradually pushed inwards until it reaches the
movable frame. When the residue of the fuel at any time upon the movable frame
is considered to be sufficiently exhausted, the frame is turned up to drop it
into the ash pit below, from which pit the ashes or residue can be removed at
any convenient time. The frame is next turned back to its horizontal position and
the fuel on the bars is pushed inwards so that a portion of it may be moved on to the
frame.
Along with the improved apparatus hereinbefore described I prefer to use a
hollow bridge into which is led air which may be either cold or heated by
passing through pipes arranged in portions of the flues, the hollow bridge being
made with orifices through which the air issues amongst the gases passing from
the furnace with the effect of preventing smoke by further promoting complete
combustion.
And in order that iny said Invention and the manner of performing the same may
be properly understood I hereunto append a sheet of drawings to be hereinafter referred
to and showing, by way of example, the application of my Invention to the internal
furnace of a horizontal cylindrical steam boiler of a common type.
Figures, 1, 2, and 3, of the drawings are, respectively horizontal, longitudinal
vertical, and transverse vertical sections as taken through the furnace and boiler. In
these drawings the same reference letters are used to mark the same or like parts
wherever they are repeated.
From the dead plate, A, the furnace space, B, is for rather more than two thirds of
its length fitted with ordinary fire bars, C, carried in the usual way on the dead
plate, A, and on cross bearers, D, E. A space between the inner ends of the fire
bars, C, and the bridge, F, is occupied by a grating, G, formed with or fixed in a
frame, which is made with trunnions, J, K, at the middles of its back and front.

page_text: The back trunnion, J, is entered into a bearing in a block fixed in the bridge, F, and
the front trunnion, K, projects through the innermost cross bearer, E, of the fire-
bars, C; and at the front of that bearer has coupled to it a spindle, L, which extends
out beyond the front of the boiler and is supported near its front end by a bracket, M.
At the front end of the spindle, L, there is fixed a clutch, N, and a lever or bar can
be applied to this clutch for the purpose of turning the spindle, I, and inverting or
inclining the movable grating, G, so as to cause the residues or ashes on it to fall into
the ash pit. Catches may be provided to keep the grating, G, in the horizontal
position except when it is being turned to drop the ashes. The bridge, F, is made
hollow and with perforations along its top for the issue of jets of air to completo the
combustion of the fuel products, the air being supplied to the interior of the bridge by
pipes, P, which in this example are led through parts of the boiler flues in order that
the air may he heated on its way to the bridge.
The apparatus, hereinbefore described is obviously adaptable without the least
difficulty to various kinds of boiler furnaces and also to various other furnaces; and
in all applications its affords extremely simple means, which, with ordinary attention
to stoking according to the easily executed method hereinbefore explained, will result
in the fuel being burned in the most economical and advantageous manner, without
smoke, and with a minimum of residues or ashes.
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. In steam boiler and other furnaces, and fitted at the inner end of ordinary fire
bars, and between them and the bridge, a perforated hearth slab or grating mounted
so that it can be inverted or more or less inclined, with means for turning the same,
substantially as and for the purposes hereinbefore described.
2. The combination in a furnace of an invertible or turnable perforated hearthslab
or grating at the inner end of ordinary fire bars, with a hollow bridge
supplied with air and made with perforations for the issue of such air amongst the
gascous fuel products, substantially as hereinbefore described.
Dated this Thirty-first day of December 1888.
EDMUND HUNT,
Applicant's Agent.