Improvements in and connected with Steam-boiler Furnaces.
Year: 1891

page_text: Date of Applicat on, 8th Oct., 1891
Complete Specification Left, 30th Dec., 1891-Accepted, 30th Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in and connected with Steam-boiler Furnaces.
We, JAMES SCOTT, Broompark, Granton, in the County of Mid Lothian, North
Britain, Steamship Manager, and JAMES ROBERT SCOTT, of the same place,
Engineer, do hereby declare the nature of this invention to be as follows, that is to
say:
This invention has for its objects to improve the construction of steam-boiler .
furnaces and parts connected therewith, to prevent or diminish smoke, and to
secure economy.
In carrying out the invention each furnace is of the internal kind being formed
within a cylindrical shell or tube or within an internal fire box of any suitable shape.
The grate bars consist of tubes placed transversely and inclined. The inner end
of the furnace space above the bars is closed by a brick partition; and the fire
gases proceed from the fuel on the bars down through between the bars and onwards
under the end partition, beyond which there is another series of inclined tubes up
through between which the fire gases have to pass. The grate and other tubes
communicate at both ends of each with the water spaces of the boiler, and by their
inclination insure a vigorous circulation of the water.
Each tube or tubular bar is made up of two lengths united by a screwed thimble
coupling; and the outer ends which project through holes in the furnace shell are
screwed to receive nuts. The nuts are placed outside the furnace shell on every
alternate tube and inside the shell on the other tubes, an arrangement allowing the
tubes to be placed sufficiently near each other. The construction of the tubular
bars as described facilitates their fixing in or removal from new or existing boilers.
Dated this Seventh day of October 1891.
EDMUND HUNT,
Applicants' Agent.
COMPLETE SPECIFICATION.
Improvements in and connected with Steam-boiler Furnaces.
We, JAMES SCOTT, Broompark, Granton, in the County of Mid Lothian North
Britain, Steamship Manager, and JAMES ROBERT SCOTT, of the same place,
Engineer 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 :—
This invention has for its objects to improve the construction of steam-boiler
furnaces and parts connected therewith, to prevent or diminish smoke, and to
secure economy.
In carrying out the invention each furnace is of the internal kind, being formed
within a cylindrical shell or tube, or within an internal fire-box of any suitable
shape. The grate bars consist of tubes placed transversely and inclined. The
inner end of the furnace space above the bars is closed by a brick partition and
the fire gases proceed from the fuel on the bars down through between the bars, and
onwards under the end partition into the flue beyond. In the case of a long
horizontal boiler another series of inclined water tubes may be arranged in the flue
beyond the partition; but in boilers of the marine type and others we prefer to
employ perforated metal plates placed horizontally beneath the water tube fire bars
in a position such that sufficient air can pass beneath them and thence up through
them to insure the complete combustion of any inexhausted fuel which may drop

page_text: through the water tube fire bars above. The fire bar water tubes communicate at
both ends of each with the water spaces of the boiler and by their inclination insure
a vigorous circulation of the water.
And in order that the said invention and the manner of performing the same may
be properly understood, we hereunto append a sheet of explanatory drawings, to be
hereinafter referred to, and showing an example of the improved furnace for steam
boilers.
Figure 1, of the drawings is an end elevation with one half in vertical section,
and Figure 2, is a vertical section as at right angles to Figure 1, of an ordinary
boiler of the marine type showing how the improvements are to be applied. In
these drawings the same reference letters are used to mark the same or like parts
wherever they are repeated.
As shown in the drawings each furnace, A, is of the internal kind being formed
within a cylindrical shell or tube, B. The grate bars consist of tubes, C, placed
transversely and inclined. The inner end, Ď, of the furnace space, A, above the
bars, C, is closed by a brick partition, E; and the fire gases proceed from the fuel
on the bars, C, down through between the bars, and onwards under the end
partition, E. Metal plates, F, perforated with holes, are placed beneath the water-
tube fire bars, C, in a horizontal position leaving a sufficient space, H, between them
and the furnace bottom to permit air to pass between them, and thence upwards
through the holes in the metal plates, F. The said perforated metal plates, F, are
employed for completely consuming any inexhausted fuel which may happen to fall
from the fire-grate bars, C, above. The flow of air between the bottom of the
water tube fire bars, C, and the perforated metal plates, F, can be regulated by a
damper, J, movable on hinges, K. A lining of firebrick, N, supported by an
inclined plate, P, extends from the inner end of the furnace to the combustion
chamber back, Q. The fire bar water tubes, C, communicate at both ends of each
with the water spaces, S, of the boiler and by their inclination insure a vigorous
circulation of the water.
Each tube or tubular bar, C, is made up of two lengths, C, C, united by a screwed
thimble coupling, T, and the outer ends, U, which project through holes in the
furnace shell are screwed into the holes and are fixed by screw nuts, W. The said
nuts, W, are screwed on both ends of each tubular bar, C, both on the outside and
the inside of the furnace shell; but in cases in which it is desired to have the
tubular bars arranged as closely together as possible, single nuts may be used such
nuts being put outside on every second bar and inside on the intermediate bars.
The construction of the tubular bars, C, as described facilitates their fixing in or
removal from new or existing boilers. The said tubular bars, C, by their
construction and fixing, also contribute materially to the strength of the furnace
shell.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1.-In a steam-boiler furnace having water-tube fire bars, and in which the fire
gases pass downwards between such bars, placing the said water-tube fire bars
transversely and inclinedly substantially in the manner and for the purposes herein-
before described.
2.-In a steam-boiler furnace of the kind referred to in the first claim, making
each water-tube fire bar in two pieces connected by a coupling, and connecting the
said bar to the furnace shell by screw nuts substantially as and for the purposes
herein before described.
m
EDMUND HUNT,
Applicants' Agent.