Improvements in or relating to Steam Generators
Year: 1897

page_text: Date of “Application, oin Jan., 1897
Complete Specification Left. 5th Oct.. 1897-Accepted. 1st Jan. 1898
Date of Application, on Jan., 1897
Complete Specification Left. 5th Oct.. 1897-Accepted. 1st Jan. 1898
PROVISIONAL SPECIFICATION.
"Improvements in or relating to Steam Generators."
I, ANTONIN MONTUPET, of 42, Boulevard Bonne Nouvelle, Paris, in the Republic
of France, Engineer, do hereby declare the nature of this invention to be as
follows:
'On board ship and in many other cases it is often necessary to have steam
generators giving a maximum of power that is to say of a maximum grate and
heating surface in a given space.
For this purpose there have been designed numbers of different boilers having
tubes arranged very close to each other, but the vaporising surface in all such
boilers has been limited by the necessity of maintaining the tubes (and the stays
if there be any) at a certain distance from each other in order not to impair the
strength of the apparatus.
The chief difference between my new generator and the generators of other
systems hitherto used is that my generator enables the tubes to be brought as
close together as desired, even close enough to touch, without any injurious effect
on the solidity thus giving the greatest heating surface obtainable within a
given space.
It has moreover the advantage of being so constructed that its parts are free
to expand, in consequence of which the boiler may be forced without any injury.
The generator according to the present invention is constituted by two steam-
chambers consisting of casings made of sheet metal or cast provided with tubes
which can freely expand that is to say each tube is fixed to only one of the casings.
The distance between the tubes is such that those of one casing pass between those
of the other, the space left between these tubes being made as small as desired;
they may be even made to touch each other when the nature of the fuel allows it.
The tubes of one set are arranged in parallel rows, the distance between each
two being equal to their diameter plus the clearance which it is desired to leave
between the tubes of the two sets when they are all in place.
Such arrangement which forms an essential and characteristic feature of my
system of boiler construction permits when fitting up a steam chamber the stays
of the chambers to be placed in the free spaces situated in front of the tubes of
the opposite steam chamber.
The tubes of the two sets being very near each other and at an angle to each
other, the combustion gases from the furnace pass into the free spaces between
the tubes of the same set completely surrounding them under much more favour-
able conditions than in any steam generators hitherto known: the cross-section
of the free passage for the gases is that of the free spaces between parallel tubes of
the two sets of tubes.
Each steam-chamber is divided by a partition-wall into two compartments
receiving circulating tubes, forming the water tubes in the interior of which
are placed the water supply tubes of a smaller diameter; the water descends
from a drum forming the top of each steam chamber through the outer compart-
ment and through the small tubes and then rises, together with the steam, through
the outer tubes and the inner compartment, again, into. the upper reservoir, or drum.

page_text: In order to render the tubes as strong as possible,
fix the lower rows in the
inner wall of the steam chamber and in the partition wall. The, holes in both
plates are a little larger than the diameter of the tubes in order to facilitate their
removal, which is still further facilitated if both the holes (in the inner and in the
partition walls) are made slightly taper in one cone.
In order to utilise the free space between the upper tubes of both steam chambers
and between the two drums arrange circulating tubes between said drums. The
small inner tubes are, in such arrangement, preferably made in two parts in
order to facilitate their, arrangement or fixing in position.
The tubes in the upper rows may be simply fitted into the holes of the inner
wall or be secured in any other suitable manner, being provided with screw-
threads conical portions or with nuts or other means of securing them in place.
For generators which have to stand a considerable amount of forcing, all the
tubes may be fixed at two points in the rear wall and in the partition-wall.
The tubes are put in place from the inside or from the outside according to the
circumstances of the case and to the available space.
As the tubes which are exposed directly to the fire are those generating most
steam, they may be made of a larger diameter in order to increase the generation
of steam.
According to the use for which they are intended the boilers are made with
tubes of a larger or smaller diameter: in the boilers for torpedo-boats, for instance,
the tubes are preferably made with a diameter of from 30 to 50mm; in those for
other small vessels, the tubes may have on the average a diameter of from 50
to 70mm and in those for large ships, their diameter is preferably from 80
to 120mm; the same applies to the boilers used in workshops, houses and the
like.
The tubes whatever be their diameter-are secured in two plates, that is to say
in the rear-wall and in the partition-wall, but in order to facilitate the dismounting
or removal of tubes of large diameter, I form the ends of said tubes slightly taper
and introduce them into holes of the same taper in the plates.
The fitting up, inspection and cleaning of the tubes is effected through holes
made in the outer walls of the steam-chambers.
In case of tubes of small and medium diameter these holes may be stopped
by screw-plugs, but for other tubes I close these holes with overlapping covers.
All the holes for introducing tubes and for inspection may be dispensed with
by providing at the outside a removable part for uncovering said tubes.
In all the tubes of my generator, the inner pressure tends to expand them and
to so tends to maintain them in place.
Another great advantage of my method consists in providing the inner tubes
with small collars, whereby they are always maintained concentric to the outer
tubes even should the latter get bent in consequence of being heated when empty.
The tubes are fixed only on one side so that their expansion is not impeded; they
may be circulating tubes with inner tubes or with a partition or even without
any such inner circulating arrangement; they may be of U-shape, more or less
bent, with two or more branches, as in certain torpedo-boat boilers, in short they
may be of any shape allowing free circulation and permitting the tubes of one set
to be placed between those of the other.
The tubes of the two sets may be at a greater or smaller distance from each other
at certain points in order to form combustion chambers serving to mix the gases
with the air in order to ignite them; a certain number of tubes may be taken out
for the same purpose, or tubes of reduced length used.
I provide also inlets for air in the front and back plates as well as in the longi-
tudinal sides of the furnace under the refractory lining; these air-inlets serve to
complete the combustion of hot gases whilst working with forced draught.
The steam-chambers may be made of sheet metal, suitably stayed or strengthened
and may extend the whole length of the boiler, but these chambers may also be
replaced, as has been mentioned by chambers or steam-collectors of any shape or

page_text: cross-section with or without partition walls, connected at the top so as to form
always two sets of tubes passing between each other.
The length of the chambers or collectors is determined by the arrangement of
the boiler or by the requirements to be met, the lower parts of said chambers taking
up all the scale or calcareous deposits, which are easily removed by scraping;
said steam-chambers may also be suitably inclined, if desired, relatively to each
other.
In one form of construction of a steam-generator according to the present inven-
tion, the front and rear walls of the generator are made removable to enable
inspection cleaning etc; but these two walls may be formed as water-containers
and may be connected to the other two sides and even, if desired, to the two upper
reservoirs, or drums which latter may be of any shape and cross-section and may
be connected in any suitable manner, or even be connected to form one longitu-
dinal or transverse body to the sides of which would be fixed the two sets of
vaporising tubes.
Multitubular generators have as a rule a great drawback, as the steam produced
contains too much water, that is to say "priming" is very great. My generator
suffers from the same drawback as it works with a very large vaporising surface.
To avoid priming I use a superheating drying apparatus based on the same
principle of circulation as my generator.
This drying apparatus is mainly constituted by a metallic casing, cast or other-
wise, above the tubes and connected in any suitable manner as by inner joints
to the two drums and provided with partition walls and with tubes which can
expand freely.
.
The steam is taken from the two drums with the usual precautions and in the
usual manner in order to avoid priming, and passes into the metallic casing through
the upper part of the front compartment, then it passes through small tubes of
the drying apparatus and returns through the large outer tubes into the back com-
partment, escapes from this compartment through large tubes at the bottom and
returns through their inner small tubes into the lower front compartment; it thus
circulates in layers or streams of very small diameter in the direction opposite to
that of the hot gases, before being led away to the engines.
The arrangement of this drying superheater has the great advantage of utilising
a free space thus obtaining, in a very simple and economical manner, an important
heating surface producing a very dry and even superheated steam.
This arrange-
ment is at the same time very economical as it perfectly utilises the hot gases
before they escape into the chimney; moreover this apparatus superheats steam
under such circumstances that, whatever be the intensity of the fire, there is no
danger of an accident, as the steam passing in the interior prevents the over-
heating of the metal.
This over-heating of the metal cannot take place unless the consumption of
steam is stopped for a considerable time, but it may be easily avoided by arranging
safety valves at the end of the drying and superheating apparatus so as to allow
the excess of the superheated steam to escape through said valves.
The superheating apparatus is placed in the current of hot gases escaping from
the vaporising sets of tubes and before they enter the chimney; and is secured
to the generator in any suitable manner, and enables the steam to be superheated
in a practical manner which has not been attained hitherto whilst its construction
affords a large heating surface in a restricted space.
Dated this 6th day of January 1897.
BOULT & WADE
Agents for the Applicant.

page_text: 66
Improvements in or relating to Steam Generators."
I, ANTONIN MONTUPET, of 42 Boulevard Bonne Nouvelle, Paris, 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:-
On board ship and in many other cases it is often necessary to have steam
generators giving a maximum of power that is to say a maximum grate-and-
heating surface in a given space.
For this purpose there have been designed numbers of boilers having tubes
arranged very close to each other but the vapourising surface in all such boilers
has been limited by the necessity of maintaining the tubes (and the stays) if there
be any) at a certain distance from each other in order not to impair the strength
of the apparatus.
The chief difference between my new generator and the generators of other
systems hitherto used is that my generator enables the tubes to be brought as close
together as desired, even close enough to touch without any injurious effect on
its strength thus giving the greatest heating surface obtainable within a given
space.
It has moreover the advantage of being so constructed that its parts are free
to expand, in consequence of which the boiler may be forced without any fear
of injury.
An example of my new steam generator is illustrated in the accompanying
drawing in which
Fig.
is a front elevation of the whole boiler one half being shown in vertical
cross section.
Fig. 2 is a longitudinal section on line X Y of Fig. 1.
'
These views are completed by details shown on a larger scale in Figs. 3 and 4.
The generator according to the present invention is constituted as may be seen
in Fig. 1 by two steam chambers consisting of casings A A¹ made of sheet metal
or cast and provided with tubes which can freely expand that is to say each tube
is fixed to only one of the casings. The distance between the tubes is such that,
as may be seen in Fig. 2 those of one casing A¹ pass between those of the other A
the space left between these tubes being made as small as desired; they may be
even made to touch each other when the nature of the fuel allows it.
The tubes of one set are arranged in parallel rows the distance beween each
two tubes being equal to their diameter plus the clearance which it is desired to
leave between the tubes of the two sets when they are all in place.
Such arrangement which forms an essential and characteristic feature of my
system of boiler construction when fitting up a steam chamber the stays of the
chambers to be placed in the free spaces situated in front of the tubes of the
opposite steam chamber.
The tubes of the two sets being very near each other and at an angle to each
other the combustion gases from the furnace pass into the free spaces between
the tubes of the same set completely surrounding them under much more favour-
able conditions than in any steam generators hitherto known; the cross section of
the free passage for the gases is that of the free spaces between parallel tubes of
the two sets of tubes.
Each steam chamber is divided by a partition wall into two compartments re-
ceiving circulating tubes forming the water tubes T T T in the interior of which
are placed the water supply tube ttt the water descends from a drum forming
the top of each steam chamber through the outer compartment D and through

page_text: the small tubes ttt and then returns together with the steam through the outer
tubes T T T and the inner compartment E again into the upper reservoir R.
In order to render the tubes as strong as possible I fix the lower rows as shown
at M in Figs. 1 and 3 that is to say by fixing them in the inner wall of the
steam' chamber and also in the partition wall. The holes in both plates are a
little larger than the diameter of the tubes in order to facilitate their removal
which is still further facilitated if both the holes (in the inner and in the partition
walls) are made slightly taper in one cone.
In order to utilise free space between the upper tubes of both steam chambers
and between the two drums RI arrange circulating tubes between said drum R
as shown at M¹ In Figs, 1 and 3. As may be seen at M¹ in Fig. 3 the small inner
tubes tt are in such arrangement preferably made in two parts in order to facili-
tate their arrangements or fixing in position.
The tubes in the upper rows may be arranged as shown at M" in Figs. 1 and 3
that is to say simply fitted into the hole of the inner wall or be secured in any
other suitable manner being provided with screw threads conical portions or with
nuts or other means of securing them in place.
For generators which have to stand a considerable amount of forcing all the
tubes are secured at two points, i.e. in the rear or inner wall and also in the partition
wall as shown in Figs. 1 and 3.
The tubes are put in place from the inside or from the outside according to the
circumstances of the case and to the space available when putting the apparatus up.
As the tubes which are exposed directly to the fire are those generating most
steam they may be made of a larger diameter in order to increase the generation of
steam.
According to the use for which they are intended the boilers are made with tubes
of a larger or smaller diameter; in boilers for torpedo boats for instance the
tubes are preferably made with a diameter of from 30 to 50mm; in those for other
small vessels the tubes may have on the average a diameter of from 50 to 70mm and
in those for large ships their diameter is preferably from 80 to 120mm, the same
applies to the boilers used in workshops houses and the like.
In order to facilitate the dismounting or removal of tubes of large diameter
I form the ends P of said tubes in the manner indicated in Fig. 4 that is to say
they are slightly tapered as at P and introduced into openings P¹, of the same
taper, in the plates (Fig. 4).
The fitting up inspection and cleaning of the tubes is effected through holes N
made in the outer walls of the steam chambers.
In case of tubes of small and medium diameter these holes may be closed by.
screw plugs as indicated at N in Fig. 3 but with other tubes prefer to form
special openings closable by plugs or covers somewhat similar to man hole covers,
these openings being made in the plates by boring three holes 0 01 011 as shown
at N¹ in Fig. 4 in order to re-allow the closing plates to be introduced and secured
in place.
All the holes for introducing tubes and for inspection may be dispensed with
by providing at the outside a removable part for uncovering said tubes.
In all the tubes of my generator the inner pressure tends to expand them and
so tends to maintain them in place.
Another great advantage of my invention consists in providing the inner tubes
with small collars P" (Fig. 4) whereby they are always maintained concentric to
the outer tubes even should the latter get bent in consequence of being heated
when empty.
The tubes are fixed only on one side of the boiler so that their expansion is not
impeded; they may be circulating tubes with inner tubes or with a partition or
even without any such inner circulating arrangement; they may also be of
U-shape more or less bent with two or more branches as in certain torpedo boat
boilers in short they may be of any shape allowing free circulation and permitting
the tubes of one set to be placed between those of the other.

page_text: The tubes of the two sets may be at a greater or smaller distance from each
other at certain points in order to form combustion chambers serving to mix the
gases with the air in order to ignite them; a certain number of tubes may be
taken out for the same purpose, or tubes of reduced length used.
I provide also inlets for air in the front and back plates as well as in the
longitudinal sides of the furnace under the refractory lining; these air inlets
serve to complete or assist the combustion of hot gases whilst working 'with
forced draught.
The accompanying drawing illustrates steam chambers of short metal suitably
stayed or strengthened and extending the whole length of the boiler but these
chambers may also be replaced as has been mentioned by chambers or steam
collectors of any shape or cross section with or without partition walls connected
at the top so as to form always two sets of intersecting tubes. When no partition
wall is employed, the tubes are attached to the inner wall in a similar manner to
that shown at M² (Figs 1 & 3).
The length of the chamber or collectors in determined by the arrangement of
the boiler or by the requirements to be met the lower parts of said chambers taking
up all the scale or calcareous deposits which are easily removed by scraping; said
steam chambers may also be suitably inclined if desired relatively to each other.
In one form of construction of a steam generator illustrated in the accompanying
drawing the front and rear walls of the generator are made removable to enable
inspection cleaning etc but these two walls may be formed as water-containers and
may be connected to the other two sides and even if desired to the two upper
reservoirs or drums which latter may be of any shape and cross section and may be
connected in any suitable manner or even be connected to form one longitudinal
or transverse body to the sides of which would be fixed the two sets of vapourising
tubes.
Multitubular generators have as a rule a great drawback, as the steam produced
contains too much water that is to say "priming" is very great. My generator
would suffer from the same drawback as it works with a very large vapourising
surface.
I remedy this drawback by the following arrangement.
To avoid priming use a superheating drying apparatus based on the same
principle of circulation as my generator.
As may be seen by examining Figs. 1 and 2 this drying apparatus is mainly
constituted by a cast or other metallic casing about the tubes and connected in
any suitable manner as by inner joints to the two drums and provided with partition
walls A B and C and with tubes which can expand freely.
The steam is taken from the two drums with the usual precautions and in the
usual manner in order to avoid priming and passes into the metallic casing
through the upper part of the front compartment F then it passes through small
tubes t t of the drying apparatus and returns through the large outer tubes T¹ T¹
into the back compartment escapes from this compartment through the large
tubes TT at the bottom and returns through their inner small tubes 11 11 into
the lower front compartment G; it thus circulates in layers of streams of very
small diameter in the direction opposite to that of the hot gases before being led
away to the engine etc through the branch H.
The arrangement of this drying superheater has the great advantage of utilising
a free space thus obtaining in a very simple and economical manner an important
heating surface producing a very dry and even superheated steam.
This arrange-
ment is at the same time very economical as it perfectly utilises the hot gases
before they escape into the chimney; moreover this apparatus superheats steam
under such circumstances that whatever be the intensity of the fire there is no
danger of an accident as the steam passing into the interior prevents the over
heating of the metal.
This over heating of the metal cannot take place unless the consumption of
steam is stopped for a considerable time but it may be easily avoided by arranging

page_text: safety valves at the end of the drying and superheating apparatus so as to allow
the excess of the superheated steam to escape said valves.
The superheating apparatus is placed in the current of hot gases escaping from
the vapourising sets of tubes and before they enter the chimney; and is secured
to the generator in any suitable manner and enables the steam to be superheated
in a practical manner which has not been attained hitherto whilst its construction
affords a large heating surface in a restricted space.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed I declare that what I
claim is:-
2
1. In a multitubular steam generator the combination of two intersecting sets
of tubes the tubes of one set being arranged in the spaces between the tubes of the
other both the sets being exposed to the direct action of the furnace substantially as
described.
2. In a multitubular steam generator a drying superheating device arranged
above the sets of tubes in the path of hot gases which circulate through it before
escaping into the chimney substantially as described.
3. In a multitubular steam generator securing the water tubes at two points
on the same side for the purpose of rendering them more rigid while enabling
them to be easily detached substantially as described.
4. In a multitubular steam generator the formation of openings for covers or
plugs for the plates formed by making three holes in the latter substantially as
described.
5. The combination and arrangements of parts constituting the complete
multitubular steam generator substantially as described and illustrated in the
accompanying drawings.
יד
100