Improvements in Steam Generators.
Year: 1893

page_text: Date of Application, 1st Aug., 1893
Complete Specification Left, 9th Apr.. 1894-Accepted, 25th May, 1894
TRUVIDIONAL DIMITTALION.
Improvements in Steam Generators.
I, GUSTAV DÜRR, Engineer, of Ratingen near Dusseldorf, in the German
Empire, do hereby declare the nature of this invention to be as follows:→
My improvements relate more particularly to water tube boilers and are illus-
trated by the accompanying drawings which represent a boiler consisting of three
principal parts, namely
1. A water chamber, which is situated in front of the tubes and serves as &
means of communication between the same, or between the tubes and the main
water reservoir.
2. A steam and water collector or upper boiler, and
3. The water tubes.
The tubes are not fitted into the tube plate in the usual manner, by means of a
tube expander, but have conical ferrules or rings, which are welded to the ends of
the tubes and turned on the lathe, the axis of the conical surface of the ferrule or
boss being perpendicular to the tube wall, and therefore at an angle to that of the
inclined tube.
A further peculiarity of this boiler consists in the fact, that the side walls of
the boiler are not made entirely of brickwork or metal plates, but are built up of
water tubes, thus increasing the heating surface of the boiler. In order that these
side tubes may be placed close together, although the diameter of their ends is
increased by the ferrules, the ends of the tubes are turned out of the axial line,
alternately to the right and to the left, as shown by Fig. 3 in horizontal section.
As marine boilers are frequently made too small and therefore liable to produce
wet steam, I provide superbeating tubes situated above the water and steam
collector, as shown by Figs. 1 and 3, through which the steam must travel forward
and backward, that is two tube lengths, before it can leave the boiler.
The steam arising from the water in the collector passes first into a tube a, a,
provided at the top with a longitudinal slot, thence the steam strikes against the
front wall b, b, of the pocket m, and rises up into the inner tubes c, c, of the super-
heater, as indicated in Fig. 1 by arrows.
After having passed through the inner tubes c, the steam returns to the front
end through the outer tubes, (that is between the inner and the outer tubes).
The water chamber situated in front of the tubes is divided into two compart-
ments fand g, by a vertical partition d, d, (Fig. 4), the front halff communicating
with the inner tubes c¹, c', while the rear compartment g communicates with the
outer tubes. In this manner a very active circulation is produced, and the tubes,
as well as other parts of the boiler are allowed to expand freely. The steam
arising from the outer tubes can escape through the rear compartment g directly
into the steam collector or upper vessel, thus avoiding excessive heating of the
tubes.
The front wall of the boiler is provided with holes, one for each tube, and placed
in the axis of the same. The said holes are closed by plugs or caps, which have
the shape of a bell or cup, in order that the said plug may take part in the expan-
sion and contraction of the front wall, and will remain steam tight without a
any
special packing device.
The pocket m serves to receive the inner tubes c of the superheater (composed
of concentric tubes) and may be let directly into the upper boiler or mounted on
the water and steam collector.
The above type of steam generator is specially intended for high pressure
о

page_text: marine boilers, on account of its lightness, facility of construction, and economy of
fuel.
1
1000'
FAIRFAX & WETTER,
Agents for the Applicant.
Improvements in Steam Generators.
I, GUSTAV DÜRR, Engineer, of Ratingen near Dusseldorf, in the German
Empire, 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 improvements relate more particularly to water tube boilers and are illus-
trated by the drawings filed with the Provisional Specification, which represent a
boiler consisting of three principal parts, namely
1. A water chamber, which is situated in front of the tubes and serves as a
means of communication between the tubes and the main water reservoir.
2. A steam and water collector or upper boiler, and
3. The water tubes.
.
The tubes are not fitted into the tube wall in the usual manner by means of a
tube expander, but have conical ferrules or rings, which are welded to the ends of
the tubes and turned on the lathe, the axis of the conical surface of the ferrule or
boss being perpendicular to the tube wall and therefore at an angle to that of the
inclined tube.
A further peculiarity of this boiler consists in the fact, that the side walls of
the boiler are not made entirely of brickwork or metal plates, but are built up
of water tubes, thus increasing the heating surface of the boiler. In order that
these side tubes may be placed close together, although the diameter of their ends
is increased by the ferrules, the ends of the tubes are turned out of the axial
line, alternately to the right and to the left, as shown by Fig. 3 in horizontal
section.
As marine boilers are frequently made too small and therefore liable to produce
wet steam, I provide superheating tubes situated above the water and steam
collector, as shown by Figs. 1 and 2, through which the steam must travel forward
and backward, that is two tube lengths, before it can leave the boiler.
The steam arising from the water in the collector passes first into a tube, a, a,
provided at the top with a longitudinal slot, thence the steam strikes against the
front wall b, b, of the pocket m, and rises up into the inner tubes c, c, of the super-
heater, as indicated in Fig. 1 by arrows.
After having passed through the inner tubes c, the steam returns to the front
end through the outer tubes, (that is between the inner and the outer tubes).
The water chamber situated in front of the boiler tubes is divided into two
compartments and g by a vertical partition d, d, (Fig. 4) the front half ƒ com-
municating with the inner tubes c', c', while the rear compartment 9 communicates
with the outer tubes. In this manner a very active circulation is produced, and
the tubes, as well as other parts of the boiler are allowed to expand freely. The
steam arising from the outer tubes can escape through the rear compartment g
directly into the steam collector or upper vessel, thus avoiding excessive heating of
the tubes.
The front wall of the boiler is provided with holes (one for each tube) placed in
the axes of the tubes. The said holes are closed by plugs or caps, which have the
shape of a bell or cup, in order that the said plug may take part in the expansion
and contraction of the front wall, and will remain steam-tight, without any special
packing device.

page_text: The pocket m serves to receive the inner tubes c of the superheater (composed of
concentric tubes) and may be let directly into the upper boiler or mounted on the
top of the same.
The above type of steam generator is specially intended for high pressure
marine boilers, on account of its lightness, facility of construction and economy
of fuel.
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 :-
1. In a tubular boiler having two sets of tubes placed one within the other, a
water chamber divided by a vertical partition into two compartments or halves
extending throughout its height and width, the front compartment communicating
with the internal or feed tubes, while the rear compartment communicates with the
outer or steam generating tubes, substantially as described.
2. In a tubular boiler, the formation of the side walls from boiler tubes in the
manner substantially as described.
3. In a steam generator, a superheater comprising in its construction two sets of
tubes placed one within the other, a steam collecting tube a and a compartment or
pocket m serving to receive the inner tubes c and to deflect or throttle the steam
arising from the tube a, substantially as described with reference to Fig. 1.
4. In water tube boilers, the construction of the plugs for the apertures in the
water chamber or vertical boiler plate, in the shape of a bell or cup adapted to
follow the expansion and contraction of the said chamber or plate and to maintain
a tight joint, substantially as described with reference to Fig. 4.
Dated this 6th day of April 1894.
FAIRFAX & WETTER,
433, Strand, London, Agents.