Improvements in Steam Boilers.
Year: 1887

page_text: Date of Application, 27th June, 1887
Complete Left, 24th Mar., 1888
Complete Accepted, 27th Apr., 1888
PROVISIONAL SPECIFICATION.
Improvements in Steam Boilers.
I PAUL ORIOLLE of Nantes, France, Shipbuilder, do hereby declare the nature
of this invention to be as follows:-
My invention relates to an improved tubulous steam boiler wherein the furnace is
enclosed by tubes and the flame space diminishes in area towards the chimney.
Reference is to be had to the accompanying drawings wherein figure 1 represents
a longitudinal sectional elevation, figure 2 a plan and figure 3 an end elevation of
one example of my improved boiler, as adapted for a torpedo boat.
According to this invention the boiler has water spaces at front and rear which
extend downwards to the level of the fire bars a and are connected by water tubes b
of which one or more rows enclose the furnace at the sides as shown. The fire door c
is in the front water space. By this arrangement the following advantages are
obtained-
(1) Increase of direct heating surface equal to 2 x L x h in which L is the length
of the tubes and the length of the furnace.
(2) Saving of the weight of the usual brick setting.
The invention thus has first for its object to increase the direct heating surface and
to reduce the weight of the boiler by dispensing with a brick setting. The improve-
ment consists in spacing the water tubes of the rows nearest the furnace wider apart
in order to afford increased space for the passage of the hotest gases. Thus, in the
example of boiler shown as applied to a torpedo boat the upper row of tubes are
0,027 millimetres apart, which gives a sectional area for the gases of 0, 49.14 at
the base of the funnel, while the tubes in the lowest row next above the furnace
are 0, 037 millimetres apart, which gives a sectional area of 0, 67-34 for the hottest
gases.
The advantages are-
(1) A corresponding increase of the grate surface without increasing the weight
of the bailan on the amantite of motor contained

page_text: (2) A diminution inversely to the increased area of the speed of the hotest gases
and a prolonged contact thereof with the heating surfaces, the coefficient t of time
playing an important part in the transmission of heat.
The same result may also be obtained in ordinary tubular boilers, by the employ-
ment of conical tubes; in which case the larger ends of the tubes would be placed
next the fire box and the smaller ends next the smoke box. The gases would then
traverse the tubes at a uniform speed throughout their length notwithstanding the
progressive cooling of the gases.

page_text: 1 PAUL ORIOLLE of Nantes, France Shipbuilder, 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 :-
My invention relates to an improved tubulous or water tube steam boiler wherein
the furnace is surrounded by water tubes and the flame space diminishes in area
towards the chimney.
Reference is to be had to the drawing accompanying my provisional specification,
wherein figure 1 represents a longitudinal sectional elevation, figure 2 a front eleva-
tion, and figure 3 a plan of one example of my improved boiler, as adapted for a
torpedo boat.
According to my invention the boiler is constructed with water-spaces at front and
rear, which extend downwards to the level of the fire bars a and are connected by
water tubes 6, of which one or more rows enclose the furnace at the sides as shown
in figure 2. The fire door c is in the front water-space. By this arrangement the
following advantages are obtained :-
(1) Increase of direct heatin gsurface equal to 2 × L × h, in which L is the longth
of the tubes and the length of the furnace.
(2) Saving of the weight of the usual brick setting enclosing the back and sides of
the furnace.
The invention thus has first for its object to increase the direct heating surface and
to reduce the weight of the boiler by dispensing with a brick setting.
Another improvement consists in spacing the water tubes wider apart laterally the
nearer they are to the furnace in order to afford increased space for the passage of
the gases whilst at their hottest temperature. Thus, in the example of boiler shown
as applied to a torpedo boat, the upper row of tubes are 1062 inches apart which
gives a sectional area for the gases of 761-7 square inches at the base of the funnel,
while the tubes in the lowest row next above the furnace are 1.455 inches apart, which
gives a sectional area of 1043-7 square inches for the gases when at their hottest.
The advantages of such an arrangement are:-
(1) An increase of the grate surface without correspondingly increasing the weight
of the boiler or the quantity of water contained.
(2) A diminution, inversely to the increase of area, in the speed of the hottest gases
and a prolonged contact thereof with the heating surfaces, the coefficient t of time,
playing an important part in the transmission of heat.
The same result might also be obtained in ordinary tubular boilers, by the employ-
ment of conical tubes; in which case the larger ends of the tubes would be placed
next the fire box and the smaller ends next the smoke box. The gases would then
traverse the tubes at a uniform speed throughout their length notwithstanding the
progressive cooling of the gases.
A further advantage derived from the above described system of boiler is that the

page_text: dirt and sediment deposit above the opening of the furnace door and also at bottom
of the rear water wall of the boiler, that the rivets are out of contact of the flame,
and that all parts of the boiler will be heated equally and gradually from the time of
lighting the fire.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
The herein described system of tubulous or water tube steam boiler wherein the
fire space is enclosed by water-tubes and water-walls without any brickwork and in
which the water tubes are arranged closer together the farther they are from the
fire-space so that the area of the flame space is gradually diminished towards the
chimney, substantially as and for the purpose specified.