Improvements in Tubulous Boilers.
Year: 1895

page_text: Date of Application, 8th Nov., 1895-Accepted, 1st Feb., 1896
COMPLETE SPECIFICATION.
Improvements in Tubulous Boilers.
I, FRIEDRICH ANDE, of 12 Szalaguteza, Budapest II, in the Kingdom of
Hungary, 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 tubulous boilers and has for its object the provision of
means whereby the evaporating capacity of the boiler is increased and at the same
time it is rendered capable of producing dry steam.
In order that this invention may be the better understood, I now proceed to
describe the same, reference being had to the accompanying drawings showing
various forms and to the letters and figures marked thereon.
According to my invention
Figure 1 is a part vertical sectional elevation of a boiler with vertical tubes.
Figure 2 is a sectional detail view of one of the series of tubes.
Figure 2 shows a modified arrangement of the ribs.
Figure 3 is a part sectional elevation of a horizontal boiler fitted with my
invention.
Figure 4 is a part plan of Figure 3.
Figure 5 is an enlarged sectional view of the tubes of the boiler shown in
Figure 3.
According to my invention I construct the water tubes of concentric tubes &
and s, Figure 2, instead of single tubes as is usual, the outer tube s is connected to
the water space and the inner tube s is connected to the steam space.
For this purpose each tubes is connected at its upper end by means of a tube l
with the water chamber W and at its lower end by tubes with the same water
chamber, while each inner tube ¹ passes through the tube and communicates at
its upper end with a tube m leading to the steam space D, and is closed at its lower
end, see Figure 2.
In the space between the two tubes s sis arranged a spiral rib k. The wall
of the tube s has numerous holes e arranged in one or more rows following the
spiral rib.
The steam is produced in the space between the concentric tubes through
which the water is passing in a spiral path and from which the steam escapes
through the before mentioned holes in the wall of the tube sinto the latter.
I have shown in Figure 2, the position of the water and steam in one of the spaces
as seen in section.
If rapid circulation of the water takes place in the steam boiler, for the creation
of which a centrifugal pump P may be inserted into the tubes according to
requirement, a separation will take place between the water and the steam in the
chamber 2 under the influence of the centrifugal force, in such a manner that the
water will flow so as to press against the wall of the outer tube with extended
surface whereby the steam is displaced towards the wall of the inner tube, where it
escapes through the holes x, see Figure 2 right hand side.
Therefore, the stream of water passing through the space z'comes into intimate
contact with a large surface of the wall of the outer tube surrounded by the fire
and is thereby rendered capable to take up quickly the heat passing therethrough.
As the steam particles produced in the stream of water travel only a short distance,
they will carry with them only few particles of water. Further, such particles of
water are thrown towards the wall of the outer tube and are there immediately.
evaporated, or they pass back into the stream of water and take part there in the

page_text: evaporation. In consequence only steam entirely free from water, enters into the
inner tube and passes through the tube m into the steam chamber D.
In the drawings the spiral rib k is sloped obliquely downwards to the axis of
the tube; but it may be normal to the. axis, if the velocity in the water is very
great.
The described arrangement may be alternatively simplified by arranging only
some short spiral ribs at considerable intervals in the space between the tubes & s¹
instead of one spiral rib extending through the whole length of this space.
Further, instead of the spiral ribs extending through the space z from the inner
wall of the tubes to the outer wall of the tube s', circular ribs may be arranged
on the wall of the tube & Figure 2* and which end at a short distance from the
outer tube s.. In that case the water flowing down through the space z will also
press towards the outer tube and the steam which is being developed will pass
towards the wall of the inner tube and escape therethrough by the holes xx.
The described arrangements may also be applied with equal success to steam
boilers with oblique or horizontal water tubes, provided that in these the water also
circulates with great velocity.
Figures 3, 4 and 5 show such an arrangement. The outer tubes s in this case
are inserted at their front ends into a chamber E, which is divided by two
partitions into three compartments e', e, e and is closed at its back end through an
end plate. The front euds of the inner tubes which are enlarged to a trumpet
shape, pass through the two compartments e¹, e³ of the chamber and enter into the
third compartment e. The back ends of the tubes are open and communicate with
the outer tube s.
A third tube is inserted into each inner tube, the curved front end of such
tube enters into the chamber e and its back end is connected to the wall of the
inner tube s', so that the space between the two tubes is tightly closed.
The compartment of the three compartments e', ee of the chamber is
connected by a tube v with the water chamber W, the water of which flows into a
centrifugal pump P, the flow pipe v of which is connected to the compartment e'.
The circulating water passes from the water chamber W into the chamber e
from there into the intermediate spaces z of the various water tubes and thence
through the inner tubes into the chamber in order to pass from there through
the before mentioned tube v back into the water chamber W and to recommence
the circuit of flow under the action of the centrifugal pump.
In the spaces
enclosed by the water tubes ss the water and steam is separated in the same
manner as explained with regard to the arrangements in Figures 1 and 2. The
steam passes through the holes xx, Figure 5, into the tubes s', thence into the
compartment and rises ultimately in the steam collector with which the com-
partment is connected through the short tube t.
In the construction as shown the centrifugal pump moves the boiler water in a
direction opposite to that in which the water tends to move through the rise of
temperature. Both actions of circulation by convection and mechanical means may
be combined if the tube v and the chamber are connected, and if the tube vis
connected to the chamber e¹, and if the centrifugal pump is turned so that its
suction pipe is connected to the pipe v¹ and its delivery pipe to the boiler W, or if
it is arranged, without turning it, so that its delivery pipe is connected to the
tube instead of to the tube v¹.
The centrifugal pump may be omitted if the water tubes s are placed very high
above one another so that the velocity of circulation of the water produced by the
difference of temperature is sufficient to press the water by centrifugal force
against the outer tubes s.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1st. A tubulous steam boiler having water tubes & each containing an inner

page_text: tubes having holes xx and a spiral rib k contained in the space between these two
tubes, the outer tubes s being connected at top and bottom, with the water
chamber, the inner tubes s being closed at the bottom end and connected at the top.
end with the steam chamber and means for the circulation of the water within the
tubes in order to cause the water passing through the space z to press against the
wall of each outer tubes which is exposed to the fire, and the steam to travel.
towards and into the inner tube s¹.
2nd. In a steam boiler as claimed in Claim 1 the substitution for the spiral rib k
of separate circular ribs r, which extend from the wall of the inner tube s¹ to.
nearly the wall of the outer tube s, substantially as described and illustrated in
Figure 24 of the accompanying drawings.
3rd. In tubulous steam boilers with horizontal or oblique tubes the arrangement
of outer tubes s closed at their back ends, and connected at their front ends to the
hindmost compartment e¹ of a triple chamber E, and inner tubes s' open at their
back ends connected at their front ends to the foremost compartment of the
triple chamber, and internal tubes provided in each of the inner tubes s¹ which
fit tightly at the back end to the wall of the latter and are connected at their front
end to the middle compartment e³, a pipe e¹ leading from the water chamber W
connected to the. compartment e', a pipe v leading to the water space connected to.
the compartment and a steam collector D connected to the compartment e³.
4th. In tubulous steam boilers with horizontal or oblique tubes the arrangement
of outer tubes s closed at their back ends, and connected at their front ends to the
hind most compartment e' of a triple chamber E, and inner tubes s¹ open at their
back ends connected at their front ends to the foremost compartment e* of the
triple chamber, and internal tubes provided in each of the inner tubes s¹ which
fit tightly at the back end to the wall of the latter and are connected at their.front.
end to the middle compartment e; a pipe v¹ leading from the water chamber W
connected to the compartment el, a pipe leading to the water space connected to
the compartment, a steam collector D connected to the compartment e³, and
means for circulating the water within the tubes, substantially as described.
Dated this 8th day of November 1895.
FELL & WILDING,
Agents for the Applicant....