Improvements in or Connected with Steam Generator (and other Furnaces and in Steam Jet Blowing Apparatus used in Con- nection therewith
Year: 1889

page_text: The decision of the Chief Examiner, acting on behalf of the Comptroller, of the
10th day of October 1894, allowed, under Section 18 of the Patents, &c.
Act, 1883, an Amendment of this Specification
COMPLETE SPECIFICATION (AMENDED).
Improvements in or Connected with Steam Generator (and other
Furnaces and in Steam Jet Blowing Apparatus used in Con-
nection therewith
We, JAMES JONES MELDRUM Engineer, and THOMAS FREDERICK MELDRUM
Engineer, both of 25 Cathedral Yard Manchester, in the County of Lancaster,
do hereby declare the nature of our said invention to be as follows:-
This invention has mainly for its object, the utilization of fuel to the best
advantage, with special reference to small and poor fuel, such as coke dust, or
breeze, coal dust, ashpit refuse, and the like.
The types of steam generator furnaces to which the invention principally relates,
are those of the Cornish, Lancashire, and Marine types, in which the fires are
contained in tubes or flues within the shell of the boiler.
means of one or more "
According to this invention the ashpit of a steam generator is closed with a plate
or front, analogous to the furnace front, and which may be provided with a door,
giving access to the ashpit. Air for combustion is supplied under pressure by
steam-jet "blowers, fixed to the ashpit front plate, in such
a manner, that the major portion of the blowers lies within the ashpit, the inlet
portion of the blowers projecting in front of the boiler only a few inches. If
small fuel is used the grate bars are put close enough together to prevent any
fuel falling through, the pressure in the ashpit above the atmospheric pressure
being sufficient to give very active combustion with the bars almost touching
each other.
A secondary supply of air may be admitted, if desired, through perforations in
the dead plate, or through a hollow bridge.
When practicable-a partition-or-wall-made of fire-clay is built-beyond-the-bridge
provided-with-a-number-of-conical-orifices,-arranged-in-such-a-manner-that-the-fire
gases-are-intimately mixed together-and--perfect-combustion is-insured-without-a
large-excess-of-air.
In the annexed Drawings which serve to illustrate the invention,
Figure 1 is an elevation of the front of one furnace of a Lancashire or Cornish
boiler, provided with improvements according to the invention.
Figure 2 is a longitudinal vertical section of the furnace at the line X X,
Figure 1.
Figure 3 illustrates in longitudinal section one form of steam jet blower, and
Figure 4 is an end view of the inlet end thereof.
Figure 5 is a longitudinal section of the inlet end of a blower, similar to
Figures 3 and 4, but provided with a valve for regulating the admission of air
thereto; and
Figure 6 is an end view of same.
Figure--is-a-longitudinal section of the inlet-end-of-a-blower, being-a-modified
form-of-regulating-valve-from-that-shown-in-Figures-5-and-6; and

page_text: Figure-S-is-a-cross-section-of-same-at-X-X-Figure-
Figure-0-shows-in-longitudinal-section-the-inlet-end-of-another-form-of-blower,
having a-regulating valve; and
Figure-10-is-an-end-view-thereof,
Figures 11-to-16-illustrate-several-arrangements of- orifices-in-the fire clay-wall
above-specified.
In all the Figures the same letters of reference are used to denote the same or
similar parts.
With reference in the first instance to Figures 1 and 2, a is the ashpit front plate
of a steam generator, provided with the door c for obtaining access to the ashpit,
the said front being bolted or otherwise suitably fixed in position; b are steam
jet blowers, one being fixed on each side of the front plate a, and lying in, or
projecting principally into the ashpit below the firebars, designated d, and the
inlets thereof being provided with valves e,-hereinafter described with reference
to Figures 5 and 6. n is the wall or partition-placed immediately-behind-the
bridge-d-and-provided with orifices-p,-shown-more fully in Figures-11 and 19
Steam is introduced to the blowers by the pipes 1, and as it issues from the nozzle
thereof into the body, draws in air and forces it into the ashpit under pressure,
rendering the combustion independent of the chimney draught.
As regards the construction of the steam jet blowers b, Figures 3 and 4 show the
simplest form that we use, its essential elements being a single steam nozzle k, a
combining cylinder h, a coned inlet i, and diverging outlet tube j;-these four
essentials-are-found-also-in-the-three-other forms of blower shown in Figures 5 to 10.
is a flange to which the steam supply pipe is connected. The nozzle k in all cases
may be central, as shown, or, annular, and may be provided with a conical spindle
for varying the area of the outlet. In Figures 3 and 4 the nozzle is connected to
the rest of the blower by means of the arms g of the head m; four arms are shown
but any other convenient number may be employed.
In Figures 3 and 5 the means or mode of attachment. of the blowers to the
plate a, closing an ashpit of a steam generator, is illustrated. It consists of a
collar formed on the neck-which fits in the aperture for it in the plate a,-and
the ring of the head m of the blower which screws into the said neck, the plate a
coining between these two parts.
With reference to Figures 1, 5 and 6, e is a cap valve, mounted over the head m
of the blower, and the sides and part of the end of which consist of alternate
bars gland apertures, corresponding with the apertures and bars 9, of the head m.
The cap is held in position by the ring e¹ of the valve, which works in a recess in
the steam flange or connecting plate 1, as shown in Figure 5. f is a handle, formed
on or connected to one of the bars gl of the valve e, and by which it is operated.
Similar-means-may-be-provided-in-the valves shown in Figures 7-to-10.
The-sleeve-and-dise-valves-illustrated in Figures-7-to-10-are-substantially-of-the
same--construction-as;-but--differ inform from that set-forth--with-reference--to
Figures 13-5-and-6. This will be clear on reference to the views, and by-the-letters
of reference of like or corresponding parts used thereon: Steam-jet-blowers provided
with valves-as-described-may-be-used-for-various purposes-where-it-is-desired--to
regulate-the-air-supply.
With-reference-to-Figure-11,-the-partition-or-wall designated-n-in-Figure-2 is
provided-with-a-number of conical orifices-p-and-q, arranged in sets of two, placed-in
such a manner-as to cause the pair of jets of combustion gases;-from-ench-set-of
orifices, to form a diminutive-whirlwind, the various whirls-together-causing a very
perfeet-admixture of the fire gases while at a high-temperature, and-enabling--the
combustion-to-be-as-complete-as-possible.
Figure 12-is-a-plan- of one element or set of two- orifices--p--and--q-(from
Figure-11), inclined towards each other in one-plane, and from each other in another
plane,-so-that-each-jet impinges-upon-the edge-of-the-other, causing-the-two-jets-te
revolve-and-combine.

page_text: In-Figure-13-the-mixing partition-n-is-one-in-which-the jets and orifices-p-and-q
are-arranged-in-horizontal lines, inclined-alternately downwards-and-upwards, with a
jet-below-a-space-and-a-space-below-a-jet.
In the mixing wall-or-partition-shown-in-Figure-14,-the-jet-and-orifices-p-and-q
Figure 15 shows another arrangement in which conical orifices-p, qand-r-in-the
mixing wall are placed in sets of three, converging-to-the centre of eneh-set.
Figure-16-shows-a-like-wall-or-partition-with-conical orifices-pall inclined with
reference to the centre-and-causing-one-rotary-motion of the body-of-gases in the
Alue.
are-arranged-in-vertical-lines-inclined-alternately-to-the-right-and-left.
The orifices-in-the-partition-or-wall-n-arranged, as shown-and-described in the
above-figures-11-to-16,-cause,-in-some-eases, a rotary-motion-and-consequent-mixing
of-the-combustion-guses;-and-in-others- a-different but-equivalent mixing, which
enables-perfect combustion of the fuel to be obtained with a smaller excess ef
oxygen-from-the atmosphere, than would otherwise be possible, thus increasing
the-temperature-and-enabling-a-larger-per-centage-of-the-hent-of-combustion-to-be
utilized
An-element of the rotary mixing-or-combining apparatus or wall, as-in-Figure 1
may-consist-of-three or more orifices, arranged-in-such-a-manner-that-the inclination
of-the-jets-eanses-a-rotary-motion-of-the-resulting combined jetor,-as-in-Figure-16
the-whole-set-of-orifices-form one-element-the-outer-orifices--being-all-inclined-with
reference-to-the-central orifice p+ the final result being one large-rotating body
filling-the-furnace-tube.
These-mixing-walls or partitions may be applied to other than steam-generator
furnaces-and-where-there-is-sufficient-space-at-disposal, we-prefer-to-use-two-or-more
partitions.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In internally fired steam generators having horizontally arranged furnaces, flues,
or tubes, the combination of a plate (or the like) by which the ashpit thereof is closed,
and one or more steam jet blowers, consisting of a simple steam nozzle, a coned inlet,
a cylindrical mixing chamber, and a diverging outlet, and the greater part of said
blower or blowers being disposed in the ashpit and under the grate bars.
2. The combination of the front ashpit plate a, and a steam jet blower or blowers b,
having a mixing tube h and a diverging outlet j adapted to lie within the ashpit
of the furnace of a steam generator, and with or without a door c; substantially as
described.
3. The combination of parts set forth with reference to Figures 1 and 2, comprising
the plate a, door c and steam jet blower or blowers b, arranged substantially as set forth
and illustrated.
4. The-mode-or-means of attachment-of the blower-b-and-ashpit-front-plate-a-;
substantially as set-forth.
5. In a steam jet-blower of-the-type-described, the-use in combination with the head
thereof,-of-a-valve, by which-the-ingress of air to the-apparatus may be controlled or
regulated substantially-as-set-forth.
6. The constructions-and-arrangements of-regulating or controlling-valves-e-and
steam-jet blower-hends,-set-forth-respectively with reference-to-Figures-5-and-6-+
-and-and 9-and-10 of the-Drawings.
7. The-use-in-a-steam generator or other furnace; of-a-wall-or-walls, partition-or
partitions, having holes or orifices, arranged and constructed substantially as set forth
for-the-purposes specified.
8. The-use-in-a-steam generator or other furnace, of a wall or partition disposed in
or-near-the-combustion chamber thereof, said wall or partition having holes or orifices;
arranged and constructed substantially-as-and-for-the-purposes set forth.

page_text: 9. A-partition adapted to be arranged-in-a steam generater-or-other furnace for the
purposes-specified, having holes-or-orifices-arranged-as-set-forth-respectively-with
reference-to-Figures 11-and-12,-13,-14, 15-and-16-of-the-Drawings.
T
1000
CHEESBROUGH & ROYSTON,
Patent Agents, 15, Water Street, Liverpool.