IMPROVEMENTS IN STEAM GENERATORS
Year: 1876

page_text: LETTERS PATENT to George William Dennistonn Scott, of Duffield, in the
County of Derby, for the Invention of "IMPROVEMENTS IN STEAM GENERATORS."
PROVISIONAL SPECIFICATION left by the said George William Dennistoun
Scott at the Office of the Commissioners of Patents on the 16th August 1876.
GEORGE WILLIAM DENNISTOUN SCOTT, of Duffield, in the County of Derby.
"IMPROVEMENTS IN STEAM GENERATORS."
My Invention relates to steam generators of the tubulous class wherein, to
facilitate thorough circulation, the currents of water and steam are guided by
circulating tubes and guide plates or deflectors.
Within a suitable furnace or brick chamber I arrange at a slight inclination from
the horizontal a number of water tubes, each of which is closed at its lower end,
and at its higher end is in communication by a vertical branch or branches, or tube
or passage, or passages with the inclined tubes next above and below it. The joints
may be packed with india-rubber rings and the tubes held together by long bolts
passing through the vertical passages. The uppermost tube of each vertical row
of tubes is arranged with its closed end higher than the end by which it com-
municates with the other tubes. The uppermost tubes of the several vertical rows
composing a boiler may be connected near their higher ends by a transverse tube
and ordinary pipe connections.
Within each of the inclined tubes (which I will call the outer tubes) is placed an
inner tube of considerably less diameter than the outer tube.
The inner tubes are open at both ends, and are of a somewhat flattened form in
cross section, so as to leave ample room for the upward flow of steam and water in
the vertical passage into which they extend, as herein-after explained. Feathers or
holding pieces are provided, so arranged as to keep the inner tube in position with
its exterior surface against or near to the interior surface of the upper side of the
outer tube.
A space is left between the lower open end of each inner tube and the corres-
ponding closed end of its outer tube, whilst the upper open end of each inner tube
extends some little distance into the vertical passage common to the open ends of
the whole of the inclined outer tubes composing each vertical row. Within this
vertical passage is arranged a compound guide plate or deflector, into which the
[Price 6d.]

page_text: ends of the inner tubes are fitted and fastened. This compound guide plate or
deflector forms a vertical division along the vertical passage, the less heated water
being at its outer side, whence it passes by the inner tubes into the closed ends of
the outer tubes and back along the space between the lower portions of the outer
circumferences of the inner tubes and inner surfaces of the outer tubes (being the
nearest to the flame and heated products from the fire-place), whilst the steam and
highly heated water from the said spaces pass out into and ascend within the
vertical passage at the inner side of the compound guide plate or deflector.
In one arrangement of my improved boiler each outer tube has cast in one with it a
sort of shaped hollow terminal, the transverse portion forming a tubular section
or part of the vertical passage, whilst the portion in line with the main body of the
tube constitutes a hand hole on which a suitable cover or door may be secured,
thereby affording ready access to each tube.
Within the transverse tubular portion grooves are formed to receive the corres-
ponding section of the compound guide plate or deflector. At the closed ends of
the tubes are formed external projections constituting supports for those ends of the
tubes, whereby they are kept at their proper relative distances apart. The steam
in the uppermost inclined tubes of each vertical row may be slightly superheated.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George William Dennistoun Scott in the Great Seal Patent Office on
the 14th February 1877.
GEORGE WILLIAM DENNISTOUN SCOTT, of Duffield, in the County of Derby.
IMPROVEMENTS IN STEAM GENERATORS."
My Invention relates to steam generators of the tubulous class wherein, to
facilitate thorough circulation, the currents of water and steam are guided by
circulating tubes and guide plates or deflectors.
Fig. 1 is a front view of my improved steam generator; Fig. 2 is a longitudinal
sectional elevation.
Figs. 3 and 4 are longitudinal vertical sections showing certain parts to a larger
scale.
Fig. 5 is a transverse section through one pair of tubes, and Fig. 6 is a plan of
the parts shewn in Fig. 3.
Within a suitable furnace or brick chamber a I arrange at a slight inclination
from the horizontal a number of water tubes b, each of which is closed at its lower
end b¹, and at its higher end is in communication by a vertical tube or passage c
with the inclined tubes next above and below it. The uppermost tube of each
vertical row of tubes is arranged with its closed end higher than the end by which
it communicates with the other tubes, as shewn at be in Fig. 2. The uppermost
tubes of the several vertical rows composing a boiler may be connected near their
Within each
higher ends by a transverse tube d and ordinary pipe connections e.
of the inclined tubes b (which I will call the outer tubes) is placed an inner tube f
of considerably less diameter than the outer tube. The inner tubes ƒ are open at
both ends and are of a somewhat flattened form in cross section, as shewn in Fig. 5,
so as to leave ample room for the upward flow of steam and water in the vertical
passage into which they extend, as herein-after explained. Feathers or holding
pieces g are provided, so arranged as to keep each inner tube f in position with its
exterior surface near to the interior surface of the upper side of its outer tube b.
A space
is left between the lower open end of each inner tube f and the corres-
ponding closed end of its outer tube b, whilst the upper open end of each inner
tube extends some little distance into the vertical passage common to the open ends
of the whole of the inclined outer tubes composing each vertical row. Within this
vertical passage c is arranged a compound guide plate or deflector h, into which the

page_text: ends of the inner tubes fit, as shewn in Figs. 3 and 6. This compound guide plate
or deflector, which is made in separate parts, as shewn full size at h in Figs. 3 and 6,
forms a vertical division along the vertical passage c, the less heated water being at
its outer side, that is to say, to the left of h in Figs. 3 and 6, whence it passes by
the inner tubes into the closed ends of the outer tubes and back along the space
between the outer circumferences of the inner tubes and the inner surfaces of the
outer tubes (they being exposed to the flame and heated products from the fire-
place), whilst the steam and highly heated water from the said spaces pass out into
and aseend within the vertical passage at the inner side of the compound guide
plate or deflector.
Hand holes are provided with covers i, i, removeable, to enable the inner tubes f
to be drawn out, leaving the plates h in the vertical tube c, wherein they may be
pushed upward, guided by the grooves shewn in Fig. 6, thus rendering the tubes d
accessible for cleaning. The large tube which is connected at top and bottom by
two horizontal pipes l, m, to the front of the generator, as shewn, is designed to aid
in keeping the water level steady.
I sometimes modify the above described arrangement of my improved boiler, as
indicated in Fig. 7, by providing each outer tube b with a sort of T shaped hollow
terminal c¹ into which the tube b is screwed, the transverse portion forming a tubular
section or part of the vortical passage c, whilst the portion opposite to and in line
with the tube 6 is formed with a hand hole, on which a suitable cover or door i
may be secured, thereby affording ready access to each tube.
The joints of the terminals c¹ are packed with rings of suitable material, such as
india-rubber of the kind usually employed for making joints of this character, and
the part held together by long bolts passing through the vertical passage they
form when put together.
Within the transverse tubular portion grooves are formed to receive the corres-
ponding section of the compound guide plate or deflector h. At the closed ends of
the tubes are supports for those ends of the tubes, whereby they are kept at their
proper relative distances apart, as shewn in Fig. 1. The steam in the uppermost
inclined tubes of each vertical row will be slightly superheated. The arrangement
may be modified by having two or more inclined tubes entering one vertical passage
side by side, and having one guide plate common to all the tubes.
And having now described the nature of my said Invention, and explained the
manner of carrying it into practical effect, I would observe that I am aware it is
not new to use inner tubes open at both ends and provided with guides or deflectors
in conjunction with outer tubes closed at one end and open to a water and steam
space at the other. Also I know it has been proposed to use inclined tubes
arranged in a furnace or fire-place in conjunction with upward passages for
supplying water and carrying off the steam generated. Therefore I do not claim
either of the foregoing features as peculiar to my Invention, nor do I claim the
exclusive right to any of the parts separately and apart from the application and
use thereof in manner and for the purpose herein-before shewn and described, but
what I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent is, the combination
of parts constituting the improved steam generator constructed, arranged, and
operating as shewn in and described with reference to Figs. 1 to 6 inclusive of the
accompanying Drawings, with or without the modification described with reference
to Fig. 7.
In witness whereof, I, the said George William Dennistoun Scott, have here-
unto set my hand and seal. this 5th day of February. in the year of our Lord