Improvements in Multitubular Boilers.
Year: 1892

page_text: Date of Application, 20th Aug., 1892
Complete Specification Left, 20th May, 1893-Accepted, 1st July, 1893
PROVISIONAL SPECIFICATION.
Improvements in Multitubular Boilers.
I, MATHIAS CHARLES DRORY, of 82 and 104 Grand Chemin de Toulon,
Quartier Mempenti, Marseilles (Bouches du Rhone) in the Republic of France,
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in multitubular boilers and consists in so
arranging the tubes that the boiler may have the form of the old low pressure
boilers employed for marine engines at the same time reserving a large combustion
chamber and completely surrounding the water tubes. The products of combustion
pass away at the front; the smoke box, the uptakes of the chimney &c. are
arranged in the ordinary way and the external form of the improved boiler will be
that of a parallelopiped; by grouping several bodies an economy of space will be
effected.
The improved boiler can be constructed as inexplosible while employing the
highest pressures in use, the connection of the tubes with each other allows of the
whole being taken down or put up or the exchange of one tube or section for
another without it being necessary to take up the deck which is of immense
importance in war ships when the decks are of sheet metal.
In carrying out the invention the boiler rests on horizontal tubes which receive
vertical tubes surrounding the furnace. Above the fire bars at the height of the
crown of the furnace of ordinary boilers are a number of horizontal tubes connected
at the front by a tube into which passes the feed water. These horizontal tubes
are provided with vertical tubes opening at the upper part into other horizontal
tubes which extend to the back of the boiler and form the crown of the combustion
chamber. A steam reservoir placed at the rear part of the body is connected to
each upper horizontal tube by three or more small tubes allowing of the passage of
steam. The spaces between the lower horizontal tubes which form the crown of
the furnace as well as the spaces between the vertical tubes surrounding the furnace
and those of the upper horizontal tubes are closed by means of small refractory
bricks. The flames pass from the fire bars to the combustion chamber licking the
underside of the lower horizontal tubes and thence through the cluster of vertical
tubes to the smoke box (provided with suitable inspection and cleansing apertures)
in order to pass either directly or by smoke passages to the chimney.
The outer walls of the boiler are provided with suitable insulating material, such
as asbestos, and with a thin sheet metal casing.
The return of the water is effected by two pipes placed at the rear of the boiler
and out of contact with the fire; which pipes open into two lower tubes; another
return tube serves to carry off any water which may have passed into the steam
reservoir.
The connection of the tubes with each other is effected, for the lower ends of
the vertical tubes, by screw-threaded sleeves and for the others by means of
turued sleeves. When required to remove a single tube or a complete section
the turned sleeves will be simply cut by a chisel; single tubes to be put in or
removed can be passed either through the fire box or the smoke box as may be
most convenient while a complete section can be passed through the smoke box
opening, the smoke box being first removed.
201
1
1000
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Multitubular Boilers.
I, MATHIAS CHARLES DRORY, of 82 and 104, Grand Chemin de Toulon,
Quartier Mempenti, Marseilles (Bouches du Rhone) 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 :-
This invention relates to improvements in multitubular boilers and consists in so
arranging the tubes that the boiler may have the form of the old low pressure
boilers employed for marine engines at the same time reserving a large combustion
chamber and completely surrounding the furnace with water tubes. The products
of combustion pass away at the front; the smoke box, the uptakes of the
chimney &c. are arranged in the ordinary way. and the external form of the
improved boiler will be that of a parallelopiped; by grouping several bodies an
economy of space will be effected.
The circulation of the water is effected by an arrangement of pipes at the back
of the boiler and completely isolated from the action of the fire.
The improved boiler is practically inexplosible although employing the highest
pressures in use; the tubes are connected together in such a manner as to allow.
of the whole being taken apart or put together or the exchange of one tube or
section for another without it being necessary to take up the deck which is of great
importance in war ships when the decks are plated with sheet metal.
To enable my invention to be fully understood I will describe how it can be
carried into practice by reference to the accompanying drawing in which :-
Figure 1 is a longitudinal section of a multitubular steam boiler constructed
according to my invention.
Figure 2 is a vertical transverse sectional elevation, the section of the left hand
half of the figure being taken through the line A B C D of Figure 1 and the
section of the right hand half of the figure being taken through the line E F G H
of Figure 1.
Figure 3 is a horizontal section on the line I J K L of Figure 1.
Figures 4 and 5 are sectional views drawn to an enlarged scale shewing the
method of connecting the vertical tubes to the lower and upper horizontal tubes
respectively as hereinafter fully described.
Similar letters in all the figures indicate similar parts.
In carrying out the invention the boiler rests on horizontal tubes a a which
receive vertical tubes bb surrounding the furnace. Above the fire bars a' at the
height of the crown of the furnace of ordinary boilers are a number of horizontal
tubes c c connected at the front by a tube d which receives the feed water. 'The
horizontal tubes c c are provided with vertical tubes e e opening at their upper
ends into horizontal tubes ff which extend from the back to the front of the
boiler and form the crown of the combustion chamber c¹. A steam receiver gs
placed at the rear part of the boiler casing d' is connected to each upper horizontal
tube by three or more small tubes b₁bb allowing of the passage of steam into
the receiver g. The spaces between the horizontal tubes c which form the crown
of the furnace as well as the spaces between the vertical tubes & surrounding the
furnace and the spaces between the upper horizontal tubes fare closed by means 4
of small refractory bricks. The flames lick the underside of the horizontal tubes c
and pass from the furnace to the combustion chamber c' and thence through the
vertical tubes e to the smoke box e¹ (provided with suitable inspection and
cleansing apertures) in order to pass either directly or by smoke passages to the
chimney.
The outer walls of the boiler are provided with suitable insulating material f¹
such as asbestos, and with a thin sheet metal casing d¹.

page_text: The level of the water will be maintained at about the middle of the horizontal
tubes ff.
The return of the water is effected by two pipes placed at the rear of the
boiler and out of contact with the fire, the said pipes h opening into the two lower
tubes a; a tube i serves to carry off any water which may have passed into the
steam reservoir.
The lower ends g' of the vertical tubes screw into the horizontal tubes as clearly
shown in Figure 4, and the upper ends are connected to the horizontal tubes as
shewn in Figure 5, by means of short tubes h expanded into the said ends and
into bosses in the horizontal tubes similarly to the manner in which the tubes
are fitted in the tube-plates of ordinary steam boilers. The horizontal tubes are
provided at their upper part with apertures closed by screw-plugs k¹ so that when
required to remove a single vertical tube or a complete section of the vertical
tubes it is only necessary to remove one or more of the plugs k¹ and then by
means of a suitable cutting tool to cut and remove the short tubes when the
vertical tubes can be unscrewed from the horizontal tubes at their lower ends or
these horizontal tubes can be removed with the lower ends of the vertical tubes
remaining therein; single tubes to be put in or removed can be passed either
through the furnace or the smoke box as may be most convenient while a complete
section can be passed through the smoke box opening, the smoke box being first
removed.
The weight including the water is greatly reduced and the cleansing of the tubes
both internally and externally can be easily effected. The sweeping of the chimney
can be performed in the ordinary manner from the side of the smoke box by means
of brushes.
A number of boilers can be united and grouped together when necessary with
longitudinal or transverse furnaces.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The manufacture and use of multitubular boilers having horizontal and
vertical tubes completely enclosing the furnace and forming a combustion chamber
as in the old type of boilers, the products of combustion passing through the cluster
of vertical tubes into a smoke box placed at the front and which can be cleaned
in the ordinary manner the tubes being connected to each other by means of screw
threads and of short tubes expanded therein whereby a tight joint is provided and
au easy separation of the parts obtained, substantially as hereinbefore described
and illustrated in the accompanying drawing.
2. The improved multitubular steam boiler hereinbefore described and illustrated
in the accompanying drawing.
Dated the 20th day of May 1902
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.