Improvements in Tubular Steam Generators.
Year: 1888

page_text: Date of Application, 27th Aug., 1888
Complete Specification Left, 23rd May, 188-Accepted. 29th June. 1889
PROVISIONAL SPECIFICATION.
· Improvements in Tubular Steam Generators.
We ALBERT DE DION, THADÉE GEORGES BOUTON and CHARLES ARMAND
TRÉPARDOUX all of 23 Boulevard de Strasbourg. Paris France Mechanical Engineers
do hereby declare the nature of this invention to be as follows:-
In the Specification to our Patent No. 4742 of 1883 we described the construction
of a steam generator consisting of a group of tubes arranged in a radiating and
inclined position which served to connect a central water chamber with a surrounding
annular one.
According to our present invention we modify this construction of steam generator
as follows.
There is a central tubular water and steam chamber connected to a surrounding
annular water chamber by inclined radiating water tubes as before. The central
chamber however has not got flues from the furnace passing through it as before,
the flames and gases from the fire being made to pass up entirely between the
radiating tubes, which are arranged in tiers above each other, the tubes in the one
tier being over the spaces in the contiguous ones. The contral chamber is extended
upward to a greater height than before and there are additional tiers of radial tubes
connecting this upper portion, through which only steam passes, which thereby
becomes effectually dried. The upper part of the central chamber is separated by a
diaphragm from the lower part so as to constitute a steam chamber containing no
water. The upper and lower ends of the central chamber are closed by covering
plates having annular grooves into the which the ends of the tubular part of the
chamber fit with suitable asbestos or other packing, and the covers are secured by tie
bolts passing right through the chamber.
The surrounding annular chamber is formed by uniting an outer cylindrical shell to
the cylindrical casing of the fire box by means of two annular plates at top and
bottom, forming the ends of the chamber, which also have annular grooves into which
the ends of the shells fit with packing, and which are secured by tie bolts passing
right through the water chamber. The supply of fuel to the furnace is either effected
by a side opening passing through the annular chamber or a central tube is provided
in the central water chamber that communicates at bottom with the furnace and is
closed at top by a cover which is removed for charging in fresh fuel.
Dated this 26th day of Angust 1888.
ABEL & IMRAY,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Tubular Steam Generators.
We, ALBERT DE DION, THADÉE GEORGES BOUTON and CHARLES ARMAND
TRÉPARDOUX all of 23 Boulevard de Strasbourg, Paris, France Mechanical Engineers
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:
In the Specification to our patent No. 4742 of 1883 we described the construction
of a steam generator consisting of a group of tubes arranged in a radiating and
inclined position which served to connect a central water chamber with a surrounding
annular one.

page_text: According to our present invention we modify this construction of steam generator
as follows.
There is a central tubular water and steam chamber connected to a surrounding
annular water chamber by inclined radiating water tubes as before. The central
chamber however has not got flues from the furnace passing through it as before, the
flames and gases from the fire being made to pass up entirely between the radiating
tubes, which are arranged in tiers above each other, the tubes in the one tier being
over the spaces in the contiguous ones. The central chamber is extended upward to a
greater height than before and there are additional tiers of radial tubes connecting this
upper portion, through which only steam passes, which thereby becomes effectually
dried. The upper part of the central chamber is separated by a diaphragm from the
lower part so as to constitute a steam chamber containing no water. The upper and
lower ends of the central chamber are closed by covering plates having annular
grooves into the which the ends of the tubular part of the chamber fit with suitable
asbestos or other packing, and the covers are secured by tie bolts passing right
through the chamber.
The surrounding annular chamber is formed by uniting an outer cylindrical
shell to the cylindrical casing of the fire box by means of two annular plates at
top and bottom, forming the ends of the chamber, which also have annular grooves
into which the ends of the shells fit with packing, and which are secured by tic
bolts passing right through the water chamber. The supply of fuel to the furnace
is either effected by a side opening passing through the annular chamber, or a
central tube is provided in the central water-chamber that communicates at bottom
with the furnace and is closed at top by a cover which is removed for charging in
fresh fuel.
The accompanying drawings shew tubular steam generators. constructed according
to our above described invention. Fig. 1 shews a vertical section and Fig. 2 a
cross section of one arrangement, and Fig. 3 shews a vertical section of the
modification in which the fuel is fed in from the top through a central tube,
applicable more particularly when coke or slow burning coal is used.
The shell of the boiler consists of the inner cylinder or fire box A and the two
outer cylinders B, C, forming together the annular water compartment, and the
central cylinder D forming the inner water compartment, which is connected by the
radial inclined tubes O to the outer annular water space. The central cylinder D is
closed at both ends by discs F F secured thereto in a water-tight manner by tie-
bolis G, the discs being formed with circular grooves into which the ends of the
cylinder are fitted in a water-tight manner with suitable packing.
The cylinder is divided in its height by a diaphragm H, placed in such a position
that there are situated above it the inner ends of one or more rows of the radiating
tubes O, the other rows of which open into the space below the diaphragm, which
alone forms the water space, the space above the diaphragm forming the steam
chamber..
The main cylinder A and two outer cylinders B, C are united together by two
annular plates K K into grooves in which the ends of the cylinders are fitted in a
water tight manner with suitable packing and which are secured together by tie-
bolts m passing through the annular waterspace.
The inner and outer cylinders are also secured together by the frame surrounding
the fire door.
The upper part of the central cylinder D has a branch pipe E through which the
steam is led off the upper part of the boiler is enclosed by a smoke-box with
chiney opening, secured to the upper annular plate K. The inner edge of the
lower annular plate K serves as support to the fire bars, and is in its turn supported
by a casing forming the ash pit.
The tubes O are so arranged that those of one row or tier are placed over the
spaces of the tier below, and the tubes of each tier being thus gradually shifted
round, helical passages or flues will thus be formed between them for the passage

page_text: of the flames and combustion gases, which take the place of the flues described in
our former patent, before referred to. The water is maintained at such a level that
there are several tiers of tubes O situated above that level, through which consequently
the steam passes that is generated in the space below the diaphragm H, it being made
to pass through the tubes into the outer annular steam space, whence it passes back
through the upper tier of tubes into the central steam space above the diaphragın,
being effectually dried on its way through such tubes.
The active circulation which is produced in the evaporating tubes produces a current
of water beginning in the outer annular water compartment, and entering the lower
end of the central water chamber through the lower tiers of tubes, whence it rises up
through the column of water contained therein, producing a violent ebulition which
causes the water level to rise up to the diaphragm H, while in the annular chamber
the water remains at its normal level, that is to say below the level of the diaphragm.
The result of this will be that the water in the central chamber, being prevented from
rising beyond tho diaphragm, will rush through the upper tubes back into the space
of the annular chamber above the water level, and in so doing, the steam carried with
the water will be readily liberated therefrom, and will pass thence, as above described,
through the upper tubes back into the space of the central chamber above the
diaphragm, where it will be stored in a thoroughly dried condition.
In the arrangement shewn at Fig. 3 the central chamber has passing through
it an inner concentric tube I secured at its upper and lower ends to the plates FF,
which in this case are of annular form, so that the central water and steam chambers
are also of annular form.
The tube I is closed at its upper end by a removeable cover, and serves for the
introduction of fuel to the fire grate below, the column of fuel in the tube I being
made to descend automatically as it is burnt away on the grate: The smoke box has
in this case a lateral opening connecting with the chimney flue.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we declare that what we
claim is :
1. In steam generators, of the kind herein referred to, the employment in addition
to the radiating inclined water tubes connecting the central, water space with the outer
annular water space, of a second upper set of radial tubes opening with their outer
ends into the steam space of the annular chamber and serving partly as additional
evaporating surface and partly for drying the steam passing through them from the
annular chamber to the central chamber, whereby a large portion of the waste heat
of the combustion gases is utilised, substantially as described.
2. In steam generators of the kind herein referred to, constructing the central
water and steam chamber of a cylinder closed at top and bottom by plates fitted
thereto in a water and steamtight manner and secured by screw bolts passing through
the chamber, substantially as herein described.
3. In the construction of contral chamber of a steam generator referred to in the
preceding claim, dividing the chamber into an upper and a lower compartment by a
transverse diaphragm, the upper compartment serving as a steam chamber and
communicating with the lower compartment only through the radial tubes and outer
annular compartment, so that the steam generated in the lower compartment has first
to pass through a lower set or sets of the tubes to the annular chamber and then
through another set or sets to the upper compartment of the central chamber, substan-
tially as herein described.
4. Constructing the outer annular water chamber of the generator referred to
in the preceding claims of two concentric cylinders, the upper and lower ends of
which are fitted in a water- and steam-tight manner in grooves formed in two
annular plates that are fixed together by screw bolts passing through the chamber,
substantially as herein described.
5. The modified construction of the steam generator described with reference to

page_text: Fig. 3 of the drawings in which a central tube is made to pass through the central
water chamber, serving as passage for the introduction of the fuel on to the fire
grate.
Dated this 22nd day of Mo.. 1880
ABEL & IMRAY,
Agents for the Applicants.