Improvements in Steam Boilers.
Year: 1889

page_text: Date of Application, 4th Dec., 1889
Complete Specification Left, 4th Sept., 1890-Accepted, 4th Oct., 1390
PROVISIONAL SPECIFICATION.
Improvements in Steam Boilers.
I, JOHN GAMGEE of 6 Lingfield Road Wimbledon in the County of Surrey,
Gentleman, do hereby declare the nature of this invention to be as follows:-
:-
My invention has reference more especially to steam boilers of the kind in which
conical flue tubes usually known as Galloway tubes are employed and its objects are
the better circulation of water, the more rapid production of steam and the prevention
of incrustation.
-6
"
When a conical tube of the Galloway type is inserted as a stay and for the extension
of heating surface in the internal flue of a boiler such as a Cornish or a Lancashire
boiler the fluid currents are from the sides to the centre of the tube and therefore
are entirely confined to the tube, forming in fact intra-tubular convection currents.
According to my invention I so form the tubes that the motionless water is forced
from below the flue, which is the coldest part of the boiler, through the tubes to above
the normal water level; each tube is thus converted into an automatic pump, a more
equable temperature throughout the boiler being thereby maintained. The active
circulation induced under all pressures naturally results in the rapid generation of
steam and prevents any deposit or formation of scale.
In carrying out my invention I continue the conical or Galloway tube above the
internal flue of the boiler to a height above the normal water level in the boiler. The
continuation may be in the form of an arch or dome gradually contracting in diameter
towards the mouth or upper end. This form of tube delivers the water at a high
velocity and in full stream. Or the continuation may be conical and be formed with
a number of orifices around its upper part so as to deliver the water all round in
smaller jets; this construction will eject an equal quantity of water to the full streami
form. Or the continuation may be in the form of a closed dome with a pipe carried
up through the top of same to a point above the normal water level and extending
down some distance into the dome. The upper part of the dome in this arrangement
will always contain an amount of steam which will act as a cushion and aid the pumping
action. Or the continuation may affect other forms.
The conical tubes will be secured to the boiler flue in any suitable manner such as
by flanges and rivets at the lower and upper ends. The continuation above the flue
may also be secured by flanges and rivets or otherwise.
With my construction of boiler tubes the "fluid-currents" before mentioned are by
means of the peculiar formation of the domes or continuations concentrated into jets
at high velocity compelling motion in one direction from the comparatively still water
below the flue into the steam space.
Dated this 4th day of Dosamhon 1000
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Patent Agent.
COMPLETE SPECIFICATION.
Improvements in Steam Boilers.
I, JOHN GAMGEE of 6 Lingfield Road, Wimbledon in the County of Surrey
Gentleman, 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:-
My invention has reference to steam boilers of the kind in which flue tubes of the
Galloway type are employed and its objects are the better circulation of water, the
more rapid production of steam and the prevention of incrustation.

page_text: When a conical tube of the Galloway type in inserted as a stay and for the extension
of heating surface in the internal flue of a boiler such as a Cornish or a Lancashire
boiler, the "fluid currents are from one side to the other of the tube, and
therefore are entirely confined to the tube, forming in fact intra-tubular convection
currents.
"
According to my invention I so form the tubes that the motionless water is forced
from below the flue which is the coldest part of the boiler, through the tubes to above
the normal water level where it is discharged in horizontal or approximately horizontal
streams or jets which fall upon the surface of the water at some distance from the
tubes; cach tube is thus converted into a sort of automatic pump, a more equable
temperature throughout the boiler being thereby maintained. The active circulation
induced under all pressures naturally results in the rapid generation of steam and
prevents any deposit or formation of scale.
In carrying out my invention I continue the flue or Galloway tube above the internal
flue of the boiler to a height above the normal water level in the boiler. The con-
tinuation is so formed as to present a gradually contracting space for the passage of
the water, the said space or passage terminating in one or more openings or outlets
adapted to deliver the water in as many horizontal or approximately horizontal
streams.
The form of the tube continuations. above the flue may vary. In the preferred form
the upper part of the continuation contains an inverted cone fixed concentrically
therein, the space between this cone and the tube continuation thus presents an annular
passage for the water which passage gradually contracts up to the outlet or outlets at
the upper part. In another form the continuation is in the form of a hollow arch or
hood gradually contracting towards the outlet at the upper end. In another form the
continuation comprises a dome which is closed at top and has a pipe carried through
the same.
The lower end of this pipe is some distance below the top of the dome and
its upper end is above the water lever and formed to deliver the water horizontally.
In this last modification the portion of the dome which is above the lower end of the
pipe will when the boiler is at work always contain an amount of steam which will act
as a cushion and aid the pumping or lifting action.
such as
The conical tubes will be secured to the boiler flue in any suitable manner,
by being welded or by flanges and rivets at the lower and upper ends. The
continuation above the flue may also be secured by flanges and rivets or
otherwise.
With my construction of boiler tubes the "fluid currents" before mentioned are by
means of the peculiar formation of the continuations concentrated into jets at high
velocity compelling motion in one direction from the comparatively still water below
the flue into the steam space into which the jets are discharged horizontally or
approximately so.
In the accompanying drawings
Figure 1 is a vertical section of an internal flue boiler fitted with flue tubes which
are provided with my continuations in the preferred form; the section is on a line
through the centre of one of these tubes and its continuation.
Figure 2 is a horizontal section on a larger scale on line 2-2 of Figure 1.
Figure 3 is an elevation of a tube and continuation similar to that shown in
Figures 1 and 2 except that the outlets are of different form.
Figures 4 and 5 are respectively vertical sections taken through the axes of the tubes
and continuations of two other modifications which differ from those shown in
Figures 1 and 2 and in Figure 3 chiefly in the external form of the continuations.
Figure 6 represents in mid vertical section a modification in which the continuation
is in the form of a hollow arch or hood gradually contracting towards the outlet at
the upper end.
Figure 7 is a similar section illustrating a modification in which the continuation
comprises a closed dome and an outlet pipe which passes through the dome and whose
lower end is some distance below the top of the dome while its upper end is above
the water level.

page_text: In all cases the flue tubes may be either conical as in Figure 1 or of cylindrical or
other form and they may either be placed in an inclined position as seen in that figure
or vertically.
Referring first to Figures 1 and 2 a is the boiler shell, 6 the internal flue and c c the
flue tubes. d d are my continuations which are somewhat conical externally and have
each a concentric internal inverted cone e, the combination of the outer cone d and
the inner cone e forming an annular water passage f which gradually contracts up to
the outlets at top. 9, 9, 9 are the outlets which are shown as being in the form of
rectangular openings or slots three in number, but their number and form may be
varied. Owing to the position of these openings and to the configuration of the upper
part of the cone e the water which rushes up the tube c and becomes concentrated into
a stream of high velocity in the gradually contracting passage f is discharged
horizontally through the outlets g into the steam space of the boiler.
Figure 3 represents a flue tube c having a continuation d which differs from that
shown in Figures 1 and 2 only in the form and number of the openings g.
Figure 4 represents a flue tube the continuation d of which is cylindrical and is not
as in Figures 1 and 2 formed in a piece with the internal cone e. The internal cone
can be fixed to the continuation d by stays h or otherwise. The upper end of the
continuation d is shown as somewhat widened so as to assist in guiding the stream of
water.
In the modification shown in Figure 5 the continuation d is in the form of an
inverted cone and the relative tapers of this cone and of the internal cone e are such
as to gradually contract the passage f.
In the modification shown in Figure 6 there is no internal cone, the continuation d
being in the form of a hollow arch or hood having a sectional area which gradually
decreases to the outlet g.
In the modification shown in Figure 7 the tube continuation consists of a tube d of
a sectional area gradually decreasing to the outlet g, this tube being fitted into and
extending some distance below the top of a closed dome i which forms an extension
of the flue tube c. In this modification there will always be when the boiler is at
work an amount of steam in the portion k of the dome above the lower end of the
tube d.
And having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:-
1. In an internal flue boiler the combination with a flue tube of an upward con-
tinuation having a gradually decreasing passage for the water and an outlet at the
upper end of said passage adapted to discharge the water in an approximately horizontal
direction above the water level of the boiler, substantially as set forth.
2. In an internal flue boiler the combination with a flue tube of an upward con-
tinuation consisting of an outer tube and an inverted inner cone, the said outer tube
and inner cone forming between them a gradually decreasing passage for the water,
and the outlet of said passage being adapted to discharge the water in an approximately
horizontal direction above the water level of the boiler, substantially as set forth.
3. The modifications of flue tube continuations respectively shown in Figures 6
and 7 and hereinbefore described.
Dated this 1st day of September 1890
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Patent Agent.