Improvements relating to Steam Generators.
Year: 1892

page_text: Date of Application, 18th Feb., 1892
Complete Specification Left, 24th Mar:, 1892-Accepted, 30th Apr., 1892
PROVISIONAL SPECIFICATION.
Improvements relating to Steam Generators.
I, ALFRED LANGTON of Deptford Pier in the County of Kent, Engineer, do
hereby declare the nature of this invention to be as follows:-
The object of this invention is to overcome the difficulties caused by the leaking
of the tubes in steam generators, more especially in connection with marine engines,
and the invention consists in a novel method of securing the ends of the tubes in
the tube plates.
may be
In carrying out my invention, I employ a ferule having a return flange at its
head, which takes into an annular recess formed in the front face of the tube plate.
The ferule may be screwed into the tube, or into the annular recess, or it
simply driven in in the usual way, the leading feature being that the parts forming
so many concentric circles will keep the tubes tight.
A similar effect may be produced by screwing the tubes in an annular recess
formed in the back of the plate.
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Dated this 18th day of February 1892.
NEWTON & SON,
Agents for the Applicant.
COMPLETE SPECIFICATION..
Improvements relating to Steam Generators.
I, ALFRED LANGTON of Deptford Pier in the County of Kent, 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:-
The leakage of the flue tubes in the boilers of steam engines, and more par-
ticularly of marine engines, is well known to be a source of much trouble and danger,
and many attempts have been made to overcome the difficulty.
In constructing tubular boilers, it is well known that the tubes are inserted in
holes in the tube plates, the ends being generally tightened up in the holes by
enlarging or expanding them with a suitable tool, known as a tube expander.
Notwithstanding the utmost care in the manufacture, leakage takes place, due to
the unequal expansion and contraction of the tubes and plate, and this is more
especially the case when forced draught is employed, as thereby the heat of the
fire is much increased, and the amount of expansion and contraction is also
increased.
In order, to some extent, to protect the ends of the tubes from the great heat,
and thereby to reduce the risk of leakage, ferrules have been used, which have
been inserted in the end of the tubes, the projecting portions being turned back on
the plate.
Now the object of the present invention is to overcome the difficulty above
mentioned, in a simple and practical manner, and the invention consists in connecting
the ends of the tubes to the tube plates, so that the greater the amount of expansion
or contraction, the tighter the connection between the tubes and the plates will
become.
In the accompanying drawings, I have shewn four arrangements for obtaining
the end in view.
The way in which I prefer to carry out my invention, is to use a modified form
of ferrule having a return flange which will fit into a cylindrical portion formed by

page_text: turning a groove in the tube plate concentric with the tube hole, but I may also
produce the same result by using the tube itself without ferrules, to fit onto the
cylindrical portion above described.
In all the figures, A is the tube plate and 13 the tube, all the parts being in
section.
In Figs. 1, 2, and 3, I have shewn the modified form of ferrule in use, the
cylindrical portion A' of the tube plate A being formed by cutting an annular
groove C in the outer face thereof, while in the modification Figure 4, I obtain
the cylindrical portion A' of the tube plate A, by cutting the annular groove C in
the inner face of the plate, and in this case I dispense with the ferrule.
The ferrule consists of a short tube D with a return external flange D', which
together form an annular recess E. This return flange fits into the annular
groove C formed in the tube plate A. The tube end and the cylindrical portion A'
of the plate, are enclosed in the annular recess E, and the ferrule is fitted into the
tube (in the arrangements shewn in Figs. 1, 2, and 3) by means of an expanding
tool in the usual way.
The ferrule may, in addition, be threaded and screwed into
the tube, as shewn at Figure 1, which arrangement I prefer to employ; or,
I may
connect the ferrule to the tube plate by threading the lange D' of the ferrule and
one side of the annular groove of the tube plate, as shewn at Figure 3.
Should the tube B (by a reduction in its diameter, due to alteration in
temperature, or from any other cause) shrink away from the tube plate A, it will
only grip the more tightly on the tubular part D of the ferrule. At the same time,
and under similar conditions, the return flange D', which fits into the annular groove
in the tube plate, will shrink onto the cylindrical portion A¹ of the tube plate.
Under the effect of expansion, the parts will be caused to grip or bind in the
reverse sense, so that the egress of the water from the boiler will in both cases be
effectually barred in both directions.
Figure 4 shows the tube threaded externally, and taking into a thread cut in one
of the walls of the annular groove C, formed on the inner face of the plate A. In
this case, as no ferrule is used, it is the tube plate that is rolled with the expanding
tool, to cause its cylindrical portion A' to fit the inner face of the tube.
Any reduction of the diameter of the tube B, it will be understood, will cause
it to bind on the cylindrical portion A' of the tube plate A, and thus effectually
prevent the passage of the water from the boiler.
I may apply my invention to one or both ends of the tubes, but in general it will
be applied to the firebox end only the smoke box end of the tubes may be fitted
in the usual way.
:
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 :-
The means above described for securing a water-tight connection between the
tube plates and the tubes of steam generators, whereby the tendency to leakage,
when the boiler is in use, will be removed as set forth.
Dated this 24th day of March 1892.
NEWTON & SON,
Agents for the Applicant.