Improvements in Locomotive Boilers.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Locomotive Boilers.
I, HENRI THUILE, Engineer of the Port of Alexandria, Egypt, do hereby
declare the nature of this invention to be as follows:-
This invention relates to a type of locomotive boiler of great strength.
In present day express locomotives the necessity of having wheels of large
diameter for, in the first place reducing the tangential speed of the parts and in
the second place the necessity of placing the cylindrical body (boiler) between
these wheels if it be not wished to inordinately raise the centre of gravity of this
body does not allow a diameter much above 125 metre to be given to the
cylindrical body.
Under these conditions, the tubular heating surface is very limited, since
experience has shewn that one cannot to any extent exceed a certain length
of the tubes.
The result is that the strength of present-day boilers cannot be increased in any
very great proportions.
Now the necessities of connections and of transport in modern travelling demand
the building of locomotives of greater speed whilst drawing greater loads, which
double result can only be attained by a much more powerful motor.
My present invention relates to further improvements in locomotive boilers,
and consists in girdling the upper and lower plates, which method may cause them
to have a semi-cylindrical shape; these may be unequal and in that case the side
walls or plates are inclined the smaller half-cylinder being at the lower part.
As a modification the shell of the lower half cylinder is prolonged upwardly by
vertical plates or walls which are connected with an incomplete cylinder forming
the upper portion of the boiler.
These arrangements are to be recommended and allow boilers to be constructed
in which the evaporating or heating surface is increased.
The side plates are suitably braced or stayed together. The whole may be
strengthened exteriorly by suitable angle iron which may be of H, T or other
section.
A similar bracing or staying with or without an outer casing, allows the boiler
to resist pressures of 20 kilogrammes and more per square centimetre.
This boiler is furnished up to a certain height with smoke tubes which serve
also to strengthen the tube plates; the upper portion serves as a steam-chest or
steam-space it is riveted on one side to the fire-box of the locomotive and the
other side it is prolonged or extended by a smoke box having two chambers
separated by a partition which is situated in the vertical plane passing along the
longitudinal axis of the boiler.

page_text: In each of these compartments of the smoke box, there abuts the exhaust of
one or more cylinders placed on the same side of the locomotive; the exhaust is
effected at the base of a separate chimney for each compartment.
By reason of the obligation to place in the space or width of the tubular body
two chimneys, I can give to these latter horizontal elliptical sections whose main
axes are parallel to the longitudinal axis of the boiler and whose lesser axes are
in the prolongation one of the other.
A boiler so formed possesses considerable strength, since, for example, a
tubular body of 4 metres 50 centimetres length, 1 metre 40 centimetres width and
2 metres 25 centimetres lateral height in which "Serve" tubes of 0065 diameter
occupy about two thirds of that height, presents or affords a tubular surface of
350 square metres and holds or contains nearly 6 cubic metres of water and 2
cubic metres of steam.
Such a boiler is therefore specially adapted for express locomotives.
גטיטגקע
I, HENRY THUILE, Engineer of the Port of Alexandria, Egypt, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:
This invention relates to a type of locomotive boiler of great strength.
In present day express locomotives the necessity of having wheels of large
diameter, in the first place, for reducing the tangential speed of the parts and, in
the second place, the necessity of placing the cylindrical body or boiler between
these wheels if it be not wished to inordinately raise the centre of gravity of
this body, does not allow a diameter much above 125 metre,--about 49 and a
quarter inches to be given to the cylindrical body.
Under these conditions, the tubular heating surface is very limited, since
experience has shewn that one cannot to any great extent exceed a certain length
of the tubes.
The result is that the strength of present-day boilers cannot be increased in any
very great proportions.
Now the necessities of connections and of transport in modern travelling demand
the construction of locomotives of greater speed whilst drawing ever increasing
loads, which double result can only be attained by a much more powerful motor.
I have already described in a concurrent application for Patent No. 12485 dated
June 3rd 1898 a system of boiler-construction which enables me to obtain a
strength much greater than that of cylindrical boilers of the best construction
hitherto known.
My present invention relates to further improvements in locomotive boilers,
The annexed sheet of drawings shews on Fig. 1 a boiler constructed according
to my invention, in longitudinal section.

page_text: Figure 2 is a diagrammatical plan view of Figure 1.
Figure 3 is a cross section of the boiler shewn in longitudinal sectional elevation
on Figure 1, the upper and lower plates being in the shape of semi-cylinders.
Figure 4 is a cross section of a modification of the boiler. Figures 3 and 4 thus
illustrate in cross-section the two ways of carrying out my present invention.
In the invention described in my former Application No. 12485 of 1898, the
boiler consists of two parallel side walls A A and affects in cross section a shape
somewhat rectangular.
I carry out my first modification thereof, or more correctly a first series of
modifications, by girdling the upper and lower plates A¹ A¹, which method may
cause them to assume a semi-cylindrical shape; these may be of unequal size or
dimensions and in that case the side walls or plates A A are inclined, the smaller
half-cylinder being at the lower part.
Figure 3 shews, by way of example, a section of such a boiler shell.
As a modification, as is shewn on Figure 4, the shell of the lower half cylinder A¹
is prolonged upwardly by vertical plates or walls which are connected with an
incomplete cylinder forming the upper portion of the boiler.
These arrangements are to be recommended and allow boilers to be constructed
in which the evaporating or heating surface is increased. As in the type of boiler
described in my previous application for patent, the plates are suitably bridged
or stayed at E E. In addition, the whole may be exteriorly strengthened by
suitable angle-bars or angle-iron of H, T, or other section.
A similar bracing or staying with or without an outer casing, allows the boiler
to resist pressures of 20 kilogrammes and more, per square centimetre.
This boiler is furnished up to a certain height with smoke tubes B which
serve also to strengthen or as supports to the tube plates; the upper portion B¹
serves as a steam-chest or steam-space; it is riveted on one side to the fire-box of
the locomotive and on the other side is is prolonged or extended by a smoke box
having two chambers DD, Figure 2, separated by a vertical partition d which
is situated in the vertical plane passing along the longitudinal axis of the boiler.
In each of these compartments of the smoke box, there abuts the exhaust of
one or more cylinders placed on the same side of the locomotive; the exhaust is
effected at the base of a separate chimney CC for each compartment.
By reason of the necessity of placing in the space or width of the tubular body
two chimneys, side by side, I can give to these latter horizontally elliptical
sections whose main axes are parallel to the longitudinal axis of the boiler and
whose lesser axes are in the prolongation one of the other.
"
A boiler so constructed affords considerable power, since, for example, a
tubular body of 4 metres 50 centimetres length, 1 metre 40 centimetre width and
Serve" tubes of 0.065 metre
2 metres 25 centimetres lateral height in which
diameter occupy about two thirds of that height, presents or affords a tubular
surface of 350 square metres, and holds or contains nearly 6 cubic metres of
water and 2 cubic metres of steam.
Such a boiler is therefore specially adapted for express locomotives.
-
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1. A type of locomotive boiler formed essentially of two side walls inclined one
towards the other connected at top and bottom by girdled plates which may be
of semi-cylindrical section, this shell or boiler being furnished with smoke tubes
which open on the one hand into the fire-box arranged at one end of this body
or boiler and on the other hand into two smoke boxes forming the other body,
these two smoke boxes being juxtaposed, separated by a vertical partition, and
each furnished with a chimney, as described with reference to the annexed drawing.
2. A modification of the type of boiler forming the subject of the preceding
claim in which the wall of the lower semi-cylinder is prolonged upwardly by

page_text: vertical walls which meet with or are connected to an incomplete cylinder forming
the upper portion of the boiler, the other arrangements of the boiler remaining
the same as in that type claimed in Claim 1, as above described with reference
to the accompanying drawing.
Dated this 17th day of March 1899.
For the Applicant,
GEDGE & FEENY,
60, Queen Victoria Street, London, E.C.,
Chartered Patent Agents.