IMPROVEMENT IN STEAM-GENERATORS
Year: 1884

page_text: I, STANISLAUS LEUTNER, Engineer, of Höfchenstrasse, Breslau, in the German
Empire, do hereby declare the nature of said invention for IMPROVEMENT IN
STEAM-GENERATORS, to be as follows:-
:―
My invention has for its object to construct a steam generator which possesses
the advantages of Field's water tube boiler without its drawbacks.
The improved generator chiefly comprises a system of vertical water tubes and
a horizontal shell serving as a water reservoir and steam collector, the tubes being
suspended from the shell.
As in Field's boilers, each vertical tube contains another tube to facilitate the
circulation of water, but the outer tubes, instead of being closed at the bottom and
entirely suspended in the fire-space, terminate in cast-iron boxes separated from the
combustion chamber or heating space by a horizontal partition, and provided with
lids or plugs to facilitate the cleaning or removal of the tubes.
The tubes are preferably arranged in four rows, and the four corresponding tubes
of each row terminate at the bottom in the same cast-iron box, so that there are as
many boxes as there are tubes in each row. In the bottom of each box there are
four plugs or lids situated opposite the respective tubes and large enough to allow
the removal of the tubes. The boxes cominunicate with each other and are
connected on the sides by means of flanges and bolts. The fire grate is placed in
front and outside of the chamber containing the tubes, and the said chamber is
divided by horizontal wrought iron partitions into superposed flues, which cause
the gases of combustion to take a zig zag course while rising to the main boiler or
shell.
:
The gases of combustion pass from the fire-bridge into the first flue situated
between the bottom plate or partition, then return through the second flue, situated
between the intermediate and the upper plate, subsequently enter the third flue,
situated between the upper plate and the bottom of the boiler or shell, and finally
pass from the back of the boiler along the right and left side to the chimney.
As the shell or main boiler is only half filled with water, the last part of the flue
serves for super-heating or drying the steam.
The outer tubes reach down to the top of the cast iron box, but the inner tubes
only extend to the level of the bottom plate or lowest partition.
·נ.ית
1

page_text: I, STANISLAUS LEUTNER, of Breslau, in the German Empire, Engineer, do hereby
declare the nature of my invention for IMPROVEMENT IN STEAM-GENERATORS,
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
Fig 1. represents a longitudinal section, Fig 2. a cross section, Fig. 3. a plan and
Fig 4. details of a steam generator embodying my invention. The generator consists
of a horizontal cylindrical boiler, the underside of which is flattened in order to
facilitate the fixing of the vertical water tubes by means of the collars welded on
the tubes. The lower ends of the tubes are open and not touched by the fire.,
From the flattened lower surface of the cylindrical boiler a which serves at the
same time as a steam collector, there are suspended twelve rows of tubes b, each
row containing, four open water tubes h, which occupy about two thirds of the
whole length of the boiler. At the lower end the four tubes h of each tube system
communicate with a cast iron box c, Figs 1. to 4.
All boxes are joined to each other and secured at the ends by screws d so as to
form a large system of tubes.
m
The 48 vertical water tubes pass through three plates e, f and g made of fire
proof material, which form the partitions of the three lower flues. In the water
tubes h, which have 93/ inner diameter and 4,5/ thickness of material, there
are freely suspended narrower tubes i. i. i. open on both sides, these tubes having
73 inner diameter and 1,5mm thickness of material. They reach to the lower
edge of the lower partition g. The tubes can be exchanged through the two man-
holes without dismounting the boiler. Any mud, which may accumulate, will
settle in the box c and can be easily withdrawn through the respective openings
after removal of the screws k; also when the boiler is empty of water, each tube h
and can be illuminated and examined.
The exterior water tubes h have 93/m clear diameter, and a clear sectional area
of 68 square centimeters; the inner tubes i have an exterior diameter of 76/
and a full sectional area of 46 sq. cm, so that an annular clearance of 22 sq. cm.
sectional area is formed.
The interior tubes i have an inner diameter of 73/m and a corresponding
sectional area of 42 sq. cm. The sectional area of the annular clearance is there-
fore to the inside sectional area of the tubes nearly as 1:2. This is said to be
the most favorable proportion for the quick generation of steam in the tubes hand
for a powerful circulation of water in.the tubes i.
.
As Field's tubes, being closed at the bottom, can never be cleaned from below,
the mud which accumulates there very soon, burns so fast, that the access of water
is impeded and the tube destroyed.
To remove this inconvenience, the inventor has adopted tubes h, open at the
bottom, and the ends of which reach down about 200/ below the fire-touched
plate g.. Therefore even if any mud is formed in the tubes, it falls into the boxes c
and cannot burn fast, as the latter are out of the reach of the fire, but as mentioned
above, the mud can easily be removed. The inner tubes i can also be easily
cleaned.

page_text: The fire lighted on the grate m, after passing the fire bridge o, comes in contact
with the vertical water-tubes h in three different heights, as shown by the directions
of the arrows in Fig. 1. The gases of combustion then play about the cylindrical
boiler from three sides and escape at last into the chimney. To prevent the hottest
fire from touching directly the two front-rows of tubes, the partition p is widened
at the right end, as shown by the drawing.
As in the cylindrical boiler a the water only occupies about half the entire space,
and as besides the gases of combustion play about the large steam space of this
boiler, the steam may be perfectly dried or even superheated.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is
A steam generator having the following peculiar features:
1, The combination of a cylindrical horizontal boiler a, with waste pipes h and i
suspended from the same and open at the lower ends which are not touched by
the fire.
2, Detachable boxes c provided with openings and lids adapted to permit the
exchange and cleaning of the pipes.
3, Partitions e, f, g, arranged so as to cause the fire or hot gases to touch the
tubes three times in succession and at a right angle.
4, A boiler a and flues arranged so, that the gases of combustion serve to dry or
superheat the steam contained in the said boiler.