Improvements in Tubes for Steam Boilers.
Year: 1892

page_text: Date of Application, 25th July, 1892
Complete Specification Left, 20th Jan., 1893—Accepted, 15th Apr., 1893
PROVISIONAL SPECIFICATION.
Improvements in Tubes for Steam Boilers.
OWEN MEREDITH 46 Laird. Street Birkenhead in the County of Chester,
Foreman Boiler Maker do hereby declare the nature of this invention to be as
follows:-
My invention relates to the construction of steam boiler tubes, and consists in
making that part of the tubes which is adjacent to the fire box tube plate less in
diameter from side to side than from top to bottom, the body of the tubes being
round, as well as the ends that are inserted into both tube plates. That part of
the tubes which is not round will be made either into two flame passages, in shape
something like the figure 8 (eight), or into any other shape that will resist external
pressure.
Between the upper and lower flame passages of that part of the tube constructed
like a figure 8, there may be openings made by corrugating the sides of the tube.
These improvements are intended to remedy a great defect created by the
inevitable tendency of the tubes to leak. The greater space which my improve-
ments will make between the tubes, will facilitate the ascent of the globules of
steam from that part of the tubes which form the region in which they are most
rapidly generated.
Dated this 23rd day of lule 1802
OWEN MEREDITH.
COMPLETE SPECIFICATION.
Improvements in Tubes for Steam Boilers.
1, OWEN MEREDITH of 46, Laird Street, Birkenhead, in the County of Cheshire,
Foreman Boiler Maker, 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 relates to tubes of the type employed in steam boilers or the like
where a large number of tubes are placed side by side between two tube plates,
and consists in compressing certain parts of such tubes to a special form in sectional
area and corresponding external shape by which I obtain a higher efficiency in the
said tubes for transmitting heat or cold from within to water or steam outside and
an increase of water or steam space between the said tubes.
And in order that it may be clearly understood how boiler or the like tubes are
constructed for the purposes of my invention, I will now proceed to describe the
same with reference to the accompanying drawing in which some convenient
forms of such tubes are illustrated in detail byway of example.
Figures 1 and 2 are corresponding views of a boiler tube the section of which
as taken on line is shown to an enlarged scale in Figure 3 and Figures 4
and 5 are corresponding views of a boiler tube the section of which as taken on
line yy is shown also to an enlarged scale in Figure 6. These tubes are to be
taken as representatives of boiler or the like tubes generally, of the type to which
my invention is applicable and are adapted in form, dimensions and arrangement to
suit the particular circumstances in which they are used.
In Figures 1 and 2 the indentations a, are intermittent and take the form shown
to an enlarged scale in Figures 3, and 8 and are pitched on either side of the tube
to alternate in the manner shown at any convenient distance apart. In Figures 4
and 5 the indentations 6 extend to a greater or less distance along opposite sides of

page_text: the tube and when deeply recessed meet together and divide the tube into two flame
or water passages in the form of the figure 8 as shown to an enlarged scale in
Figures 6 and 7.
C
At the ends and the parts d which come between the indentations the tubes
retain the usual circular form. When the indentations are wholly closed together
as shown in Figure 6, I prefer to corrugate them along the line of contact in the
manner shown in Figure 7, so that the gases or fluids within instead of being
divided by separate passages are free to diffuse themselves through the corrugations e,
and so to be brought into intimate contact with as much internal tube surface as
possible, by which to increase the efficiency of the tube for transmitting the heat or
cold within to the water or steam outside.
It will be observed that the extent to which the tubes are reduced in width by
the indentations is so much increase of the water or steam space between them and
that in consequence the ascent of the globules of steam is facilitated in the region
in which the said globules are most rapidly generated.
Having described in what way my invention can be usefully applied to the tubes
of steam boilers or the like I would observe that I do not confine myself to the
particular forms and arrangements of indentations in the tubes as shown in the
figures, nor to the use of the invention in connection with steam boilers only as
the invention can be similarly applied to tubes employed for the like or analogous
purposes such as the tubes of surface condensers or the tubes of a refrigerator
where the object is to transmit the effect of a low temperature within the tubes to
the surrounding medium added to which the extent and position of the indentations
can be varied or graded from the smaller indentations shown in Figures 3, and 8
to the deeper and longer indentations shown in Figure 6 as may be found desirable.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
"
Firstly In steam boilers or the like, the use of tubes in which certain parts are
compressed to the special form and sectional area, as and for the purpose as
herein before described and illustrated by way of example in the accompanying
drawing.
Secondly In steam boilers or the like the use of the tubes constructed as and
for the purpose as hereinbefore described and illustrated in Figures 1, 2, 3, and 8.
Thirdly-In steam boilers or the like the use of tubes constructed as and for the
purpose as herein before described and illustrated in Figures 4, 5 and 6, and with or
without the corrugations at e as illustrated in Figure 7.
Dated this 19th day of January 1893.
G. J. CLARKSON,
Chartered Patent Agent,
Stockton-on-Tees, Agent for the said Owen Meredith.