Improvements in Tubular Steam Boilers.
Year: 1893

page_text: Date of Application, 10th July, 1893
Complete Specification Left, 5th Jan., 1894-Accepted, 10th Mar., 1894
1
PROVISIONAL SPECIFICATION.
Improvements in Tubular Steam Boilers.
I, FRANK KENNEDY, of 1, Campsie Terrace, Greenock in the County of
Renfrew, North Britain, Engineer, do hereby declare the nature of this invention
to be as follows, that is to say :-
My said invention has for its objects to increase the heating surface and to
improve the construction of certain parts of tubular steam boilers.
In carrying out my invention in the case of a boiler which, in some respects, is
like a common type of marine boiler, and which has a main shell of a horizontal
cylindrical form, and two or three internal furnaces communicating with a
combustion chamber at their inner ends, I make the combustion chamber of an
improved form, and with its upper part semicircular or nearly so in vertical section
as at right angles to the axis of the boiler, the semicircular part being curved or
corrugated in section as from front to back of the boiler. The lower part of the
combustion chamber is by preference shaped to form approximate segmental
extensions backwards from the lower parts of the furnace shells, such part being
strengthened by angle-iron. The inner ends of the furnace shells are formed with
vertical flanges at their upper and inner sides, the flanges of adjacent furnace
shells being welded together or suitably riveted, the two or three furnaces being
thereby united together, and being entered together into the boiler, and the joint
vertical flange being directly riveted to the inner tube plate.
At the back of the boiler there is formed a second or back chamber which is
enclosed in a casing lined with firebrick, and which communicates with the
combustion chamber by short tubes of comparatively large diameter. Fire gas
tubes extend from the combustion chamber in the ordinary way to smoke boxes at
the front of the boiler, these tubes occupying a space limited by the semicircular
roof of the combustion chamber; whilst the spaces between the said tubes and the
sides of the boiler are occupied by longer fire gas tubes extending from the back
chamber to the front of the boiler-these last mentioned tubes being by preference
of somewhat larger diameter than the shorter tubes extending from the combustion
chamber to the front of the boiler.
Forced draught is by preference employed in working boilers of the improved
construction hereinbefore described.
Dated this winhth do. of T... 1002
EDMUND HUNT,
Applicant's Agent.
COMPLETE SPECIFICATION.
Improvements in Tubular Steam Boilers.
I, FRANK KENNEDY, of 1, Campsie Terrace, Greenock in the County of
Renfrew, North Britain, 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 :-
My said invention has for its objects to increase the heating surface and to
improve the construction of certain parts of tubular steam boilers.
In carrying out my invention in the case of a boiler which in some respects,
is like a common type of marine boiler, and which has a main shell of a horizontal
[Price 8d.1

page_text: cylindrical form, and two or three internal furnaces communicating with a
combustion chamber at their inner ends I make the combustion chamber of an
improved form, and with its upper part semicircular or nearly so in vertical
section as at right angles to the axis of the boiler, the semicircular part being
curved or corrugated in section as from front to back of the boiler.
At the back of the boiler there is formed a second or back chamber which is
enclosed in a casing lined with firebrick, and which communicates with the
combustion chamber by short tubes of comparatively large diameter, and which
also communicates, by other fire gas tubes, with the smoke boxes in front of the
boiler.
And in order that my said invention and the manner of performing the same
may be properly understood I hereunto append two sheets of explanatory drawings,
to be hereinafter referred to, and showing tubular steam boilers as made with my
improvements.
Figure, 1, on Sheet, 1, of the drawings is a front elevation of a boiler (one half
of it being in vertical section).
Figure, 2, is a longitudinal vertical section of the same boiler.
Figure, 3, on Sheet, 2, is a back elevation of the same boiler (one half of the
back combustion chamber being shown in vertical section).
In these
drawings the same reference letters are used to mark the same or like parts
wherever they are repeated.
Figure, 4, is a longitudinal vertical section of part of another boiler.
In the case of the boiler shown in Figures, 1, and, 2, on Sheet, 1, and Figure, 3,
on Sheet, 2, which has a main shell, A, of a horizontal cylindrical form, and three
internal furnaces, B, communicating with a combustion chamber, C, at their inner
ends, I make the combustion chamber of the improved form shown, its upper
part, D, being semicircular or nearly so in vertical section as at right angles to
the axis of the boiler, the semicircular part being curved or corrugated in section
as from front to back of the boiler. The lower part, E, of the combustion
chamber, C, is by preference shaped to form approximate segmental extensions
backwards from the lower parts of the furnace shells, B, such part being
strengthened by a T-iron, F. The inner ends of the furnace shells, B, are
formed with vertical flanges, G, at their upper and inner sides, the flanges of
adjacent furnace shells being welded together or it might be suitably riveted, the
three furnaces being thereby united together, and being entered together into
the boiler and the joint vertical flange being directly riveted to the inner tube
plate, H.
At the back of the boiler there is formed a second or back chamber, J, which
is enclosed in a casing lined with firebrick, K, and which communicates with the
combustion chamber, C, by short tubes, L, of comparatively large diameter.
Fire gas tubes, M, extend from the combustion chamber, C, in the ordinary way to
smoke boxes, N, at the front of the boiler, these tubes occupying a space limited
by the semicircular roof, D, of the combustion chamber, C; whilst the spaces
between the said tubes, M, and the sides of the boiler are occupied by longer fire
gas tubes, P, extending from the back chamber, J, to the front of the boiler,
these last mentioned tubes being by preference of somewhat larger diameter than
the shorter tubes, M, extending from the combustion chamber, C, to the front of the
boiler. A damper, Q, is provided in the smoke box, N, at the front of the boiler,
by means of which the passage of the fire gases through the tubes, M, can
be regulated, so as if necessary to compel part of them to pass through the
tubes, L, the back chamber, J, and tubes, P. The damper, Q, is hinged at its
bottom part, and it is worked by a handwheel, R, and screw bar, S, the latter
being jointed to the middle part of the damper, and passing out through the
front of the smoke boxes, N, where it engages with the handwheel.
In Figure, 4, part of a boiler is shown in which some details are modified so as
to be less expensive to construct. The furnaces, B, and the upper part, D, of
the combustion chamber, C, are not corrugated, and the former have no vertical

page_text: flanges on their inner ends, the tube-plates, H, being flanged out to meet them.
Instead of the firebrick, K, in the back chamber, J, plates, T, are fixed to the
inside and outside of the chamber, so as to enclose air spaces.
Forced draught is by preference employed in working boilers of the improved
construction hereinbefore described.
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. The improved construction of tubular steam boiler substantially as
hereinbefore described and as shown in the accompanying drawings.
2. In tubular steam boilers, making a combustion chamber with its upper part
semicircular or approximately semicircular in vertical section, and corrugated or
uncorrugated in section as from front to back of the boiler substantially as and
for the purposes hereinbefore described, and as shown in the accompanying
drawings.
3. In tubular steam boilers combining the usual combustion chamber with
another chamber fixed at the back of the boiler, the two chambers communicating
with each other, and with the smoke boxes by fire gas tubes, substantially as
hereinbefore described and as shown in the accompanying drawings.
Dated this Fourth day of January 1894.
EDMUND HUNT,
Applicant's Agent.