Improvements in Water Tube Boilers."
Year: 1897

page_text: Date of Application, 6th Oct., 1897--Accepted, 11th Dec., 1897
"Improvements in Water Tube Boilers."
I, ADOLPHE FRANÇOIS EUGENE DUPONT, of Rue Sandin, Toulon-sur-Mer, in the
Republic of France, 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 object of my invention is to provide a water tube boiler in which the cir-
culation of the water and the action of the flame are advantageously effected and
the hot products of combustion are efficiently utilized and whereby the sweeping
of the tubes can be readily done.
According to my invention each element of the boiler has an exterior descending
pipe which conducts the water from the steam collector to the bottom of a feed
pipe into which the water tubes of the boiler open, so that the steam collector is
the only part of the water space which is common to the various elements and
therefore each of the elements is distinct from the others; but in certain cases, in
order to simplify the construction, a single descending pipe may supply two feed
pipes.
At convenient levels, I. provide, between the sets of tubes and their connecting
boxes, spaces, sufficient to constitute between the sets or series of tubes a number
of inclined and inter-crossing passages through which the flame and products of
combustion pass without danger of the flames becoming extinguished, the gases
being mixed and thoroughly consumed.
I so arrange the sides of the connecting boxes for the tubes, and give an
obliquity, in relation to the front of the boiler to the two vertical planes in which
the lower branches and The upper branches of the tubes belonging to the same
vertical series are situated, that the length of the connecting boxes is shortened,
and a space is formed between the ends of the connecting boxes which are on the
same level, sufficient for permitting of the direct sweeping of each of the steam
tubes.
I provide a transverse connection with the steam collector, which connection
receives the feed water and is provided with a partial barrier, so that it constitutes
a purifying receptacle for the feed water. The level of water therein is indepen-
dent of that of the steam collector; and the relative indications of these two levels
of water are very important, especially in the case of marine boilers.
I employ the pipes which conduct the water into the tubes, to support the steam
collector.
In order that my invention may be fully understood I will describe it in
reference to the annexed drawings in which :-
Figure 1 is a vertical section of a boiler constructed according to my invention,
this section being taken on the line 3-4 of Figures 2 and 3.
Figure 2 shews at the part y a plan of the boiler and at the part a and ẞ two
horizontal sections taken respectively on the lines 15-16 and 13-14 of Figures 1,
3 and 4.
Figure 3 shews at the part a the front of the boiler and at the part ẞ a vertical
section on the line 5-6 of Figures 1 and 2,

page_text: Figure 4 shews at the parts y and S two vertical sections, the first on the
line 7-8-9-10 and the second on the line 11-12 of Figures 1 and 2, this latter
section being a rear view.
Figure 5 shews at the parts a and 3 two horizontal sections taken respectively
on the lines 15-16 and 13-14 of Figure 6.
Figure 6 shews a section on the line 7-8-9-10 of Figures 1 and 5; but in
order to simplify the Figure, the orifices made in the front of the pipes for the
connection of the steam tubes are not shewn.
Figure 7 is a vertical section on the line 31-32 of Figures 8 and 9.
Figure 8 shews at the parts a and 8 two horizontal sections taken respectively
on the lines 15-16 and 13-14 of Figures 7 and 9.
Figure 9 shews at the parts y and & vertical sections taken respectively on the
line 7-8-9-10 and on the line 11--12 of Figures 7 and 8, this latter section
being a rear view.
Figure 10 is a view shewing the connection of the water tubes with the boxes.
A is the steam collector; B is the transversally placed addition thereto; Cis the
partial barrier; D represents the ascension pipes and E the feed pipes; F are the
lower branches of the various water tubes of each vertical series; G are the con-
necting boxes and the upper branches of the water tubes; F G and H¹ are
the similar elements constituting the water tubes of the vertical series; I is a
girder supporting the addition B of the collector; J are the doors in the front
giving access to the connecting boxes G and G¹; K are the inspection doors of
the tubes D and E; L are the doors of the fire box; M those of the ash-pit; N is
the ash-pit; the fire-bars; P the furnace; Q the fire-bridge; R the smoke box;
S the chimney; T the lagging of the boiler; U are plates for regulating the
passage of the products of combustion across the series of tubes; V is the purify-
ing space in the addition B for the feed water; X are the spaces between the ends
of the connecting-boxes. Y are the descending water pipes divided, or not, into
two parts by a longitudinal partition; Z shews the spaces constituting ways for
passage and mixing of the flames and products of combustion.
+
the
In Figures 1 to 4 two pipes I and two pipes E are shewn cast in one piece. A
greater number may be similarly cast if convenient.
Figures 5 and 6 shews the arrangement of the pipes when more than two cast-
ings cannot be conveniently made together.
The same letters represent the same parts as in Figures 1 to 4 and the same
Figures represent the same section lines.
My invention is not limited to the mode of casting the pipes together as this
may be done as is most convenient in practice.
The upper end of the pipes Y for the return of the water may be in indirect
communication with the steam collector A as in the arrangement shewn in
Figures 7 to 9, in which this communication is effected by means of an inter-
mediate compartment W.
In these Figures 7 to 9 there are shewn only the parts of the boiler which are
modified by the use of this compartment W; the same letters represent the same
parts as in Figures 1 to 4, the same Figures representing the same section lines.
Figure 10 shews on a larger scale the convergence of the two planes which
contain the axes of the two branches of a vertical series of water tubes as well as
the resulting spaces X between the ends of the connecting boxes.
In this Figure 10 the lines 19-20 and 21-22 shew the limits of one of the
elements of the boiler; the line 23-24 indicates the vertical plane containing the
axes of the lower branches F of all the tubes of this element which are super-
posed in the same vertical series; the line 25-26 indicates the similar vertical
plane containing the axes of the upper branches H which complete, with the connect-
ing boxes G, the water tubes of the series in question. The lines 27-28 and 29-30
indicate the planes which contain the axes of the lower and upper branches FI
and H of the water tubes of the same element but belonging to the next vertical
series.

page_text: The distance between 24 and 25 is less than that between 23 and 20; and the
distance between 28 and 29 is less than that between 27 and 30, and the four
lines 23-24; 25-26; 27-28; and 29-30 are oblique to the front of the boiler.
Figure 10 shews in plan a broken section made following planes which are
normal to the longitudinal plane of symmetry of the boiler and which pass through
the respective axes of the lower and upper branches F" and H and through the
axis of their connecting box G¹.
Having described the various parts constituting the boiler, I will explain their
working referring to the arrangement shewn in Figures 1 to 4 and 10.
The water from the collector A descends by the pipes Y each of which feeds two
elements of the boiler, in common when there is no longitudinal partition divid-
ing it into two, which is the case with the pipe Y in the part ẞ of Figure 2, or
when it has the dividing partition shewn in the part a of Figure 2. This water
arriving at the bottom of each of the two feed pipes E, ascends in each of them,
and encounters the entrance orifices of each of the lower brances F and F of the
water tubes which open thereinto and which orifices are nearest the furnace and
the water passes into these lower branches; it there becomes partly converted into
steam; and passes, together with the steam produced, through the connecting
boxes G and G¹ and then through the upper branches H and H of the tubes,
Further steam is generated during this second passage and the water and steam,
discharge into the ascension pipe 1) and the whole passes back into the steam
collector A.
The bursting of a tube of one element does not affect in any way the tubes of
another eicament, these retaining their own water, Blow-off cocks placed at the
bottom of each pipe E allow of the boiler being completely emptied without being
otherwise opened.
Rolling and pitching of ships in which the boilers may be used disturb neither
the circulation of the water nor the liberation of the steam produced.
When the pipes Y have no partition the group of the two elements which it
feeds is completely independent of the other similar groups, but the two elements
of a same group are of course partly in communication with each other.
In the boiler shewn in Figures to 4 the products of combustion from the fire-
box P ascend, pass partly between the lower branches F F of the lower part of the
series of tubes whilst the remainder pass into the ways Z, the lowest of which has
an area sufficiently large not to extinguish the flame. This flame on arriving at
the connecting boxes G G¹ passes into another of the inclined ways Z, which con-
ducts it back towards the pipes E and D, and the flame thus proceeds through over
and under the several series of tubes, encountering on its way the gaseous pro-
ducts which have passed through between the tubes whereby a thorough mixing
and burning of the products of combustion is ensured these spaces Z between the
connecting boxes allowing of easy sweeping of the exteriors of the series of tubes,
and the spaces X hetween the ends of the boxes allowing of each of the tubes being
swept separately whilst working.
I do not limit myself to the precise details, for example, I may employ water
tubes of any system, such as cylindrical tubes, smooth tubes, ribbed tubes, or
tubes of different diameters in their two branches or in various parts of the boiler.
I may also modify the number and the position of the rows or series of water
tubes and I may employ collecting boxes for any number of water tubes.
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. In water-tube boilers, having tubes divided into elements each consisting of
a vertical row or vertical rows of water tubes each formed of two branches inclined
to the horizontal, and joined by a connecting box the arrangement herein described
allowing the water from the steam collector to descend by pipes which each pass
their share of water to the bottom of a feed pipe or feed pipes up which the said

page_text: water passes and enters therefrom the water tubes of the element, at the end
nearest the fire.
2. In boilers of the type described, the provision of spaces between super-
posed connecting boxes and the formation of inclined and inter-crossing ways
between the series of water tubes substantially as hereinbefore described.
3. In boilers of the type described the convergence given to the two vertical
planes which contain respectively the axes of the lower branches of the water
tubes of a vertical series, and the axes of the corresponding upper branches, this
convergence creating a space between the ends of the connecting boxes of a same
level, substantially as hereinbefore explained.
4. In boilers of the type described, a transverse connection with the steam
collector the said connection being furnished with an internal barrier which con-
stitutes a compartment for the purification of the feed water, the said connection
having a water level about that of the steam collector but independent thereof.
5. In boilers of the type described, the employment of feed pipes or ascending
pipes or both as supports for the steam collector substantially as hereinbefore
described.
6. The arrangement and combination of parts constituting a water-tube boiler
substantially as herein before described and shewn in Figures 1 to 4 and 10 of
the accompanying drawings, or modified as shewn in the other Figures.
Dated this 6th day of October 1897.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.