Improvements in and connected with Smoke Tubes for Boilers and the like.
Year: 1893

page_text: Date of Application, 11th Dec., 1893
Complete Specification Left, 11th Jan., 1894-Accepted, 10th Mar., 1894
PROVISIONAL SPECIFICATION.
Improvements in and connected with Smoke Tubes for Boilers and
the like.
NICHOLAS SWANSON HAWKS, Engineer, 27 Atherton Road Forest Gate
London E. I do hereby declare the nature of this invention to be as follows :-
I construct a conical ribbed ferrule or socket of steel or other metal & fit it in
the outer end of smoke or heat tubes selected, thereby reducing the area of outlet
so that the heat which otherwise would quickly escape, is distributed to lower
heating surfaces before it escapes to the funnel.
The conical ribbed ferrule is so constructed that it can be instantly withdrawn
& replaced for cleaning purposes.
COMPLETE SPECIFICATION.
Improvements in and connected with Smoke Tubes for Boilers and
the like.
1, NICHOLAS SWANSON HAWKS of 27 Atherton Road, Forest Gate, London, E.
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 :—
It is well known that in boilers in which there are a number of tubes through
which the smoke or hot gases pass on their way for example from the combustion
chamber to the smoke box a much larger proportion of the smoke or gases passes
through the tubes at the upper and middle parts of the series than through those at
the other parts. Now the object of my invention is to distribute the heat or gases
more evenly among all the tubes so that they may all give passage to approximately
about the same quantity of heat or gases and all do practically equal work. The
heat is thus utilized in a more efficient manner.
With this object I reduce the area of the outlet end of all or of most of those
tubes, through which the smoke or gases naturally tend to flow, say those in the
3, 4 or 5 rows next to the top according to the size and description of boiler and
the number of rows of tubes. The passage of the smoke or gases through these
reduced or partially obstructed outlets being thus limited the hot gases are com-
pelled to a proportionate extent to find their way through the unobstructed or full
bore tubes.
In carrying out my invention I preferably employ for the purpose of reducing
the area of or partially obstructing the passage through the said tubes a conical
ribbed ferrule or piece of steel or other metal which I fit into the outlet end of the
tube, the said piece being capable of being readily withdrawn when the tube bas
to be cleaned or plugged in case of leakage and then again as readily replaced.
Figure 1 of the accompanying drawings is a view of the outer end (as seen from
the inner end) and
Figure 2 a partial longitudinal section of a flue tube fitted with a conical ribbed
piece as and for the purpose herein before described.
Figure 3 is an end view of a series of flue tubes arranged in a boiler some of
these tubes being fitted with partial obstructors according to my invention.
.

page_text: a a Figure 3 represent the tubes and bb the conical ribbed pieces or partial
obstructors. As shown each of these pieces consists of a centre piece having three
equidistant ribs ccc each of which is of gradually decreasing width so that the
piece is conical and can be readily pushed into and more or less jammed in the end
of the tube a. d is a projection to enable the piece to be taken hold of by a pair of
tongs or the like when it is required to withdraw the piece to allow of the tube
being cleaned or plugged.
Although the piece is preferably of the form shown it is obvious that various
other forms may be adopted that will effect the purpose of my invention namely to
reduce the area of or more or less obstruct the outlet end of the tube. For
instance the number of ribs can be varied or there may be a passage through the
centre piece or a ring or ferrule may be fitted against the inner wall of the tube at
the outlet end, or part of the tube preferably the upper part may be closed at the
outlet end by a plate or disc, or excentric ring.
I have described my invention as applied to boilers. for which purpose it is more
particularly applicable but it is also applicable to other like apparatus which have
a number of superposed rows of smoke tubes such for example as heaters in which
air on its way to the furnace is heated by tubes through which the smoke passes on
its way to the funnel.
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. In boilers or the like which have a number of tubes for the passage of smoke
or hot gases, fitting the outlet ends of all or some of the tubes situated at the parts
to which the smoke or gases naturally tend to flow with pieces which reduce the
area of or partially obstruct the passage through the said outlet ends, substantially
as and for the purpose herein before described.
2. In boilers or the like which have a number of tubes for the passage of smoke
or hot gases,. fitting the outlet ends of all or some of the tubes situated at the parts
to which the smoke or gases naturally tend to flow, with removable conical ribbed
pieces, substantially as and for the purpose hereinbefore described.
Dated this 11th day of January 1894.
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Chartered Patent Agent.