IMPROVEMENTS IN OR RELATING TO STEAM BOILERS AND IN SUPER HEATERS THEREFOR to be as follows
Year: 1885

page_text: I MAX GEHRE, engineer of Düsseldorf-Grafenberg, Prussia, German Empire do
hereby declare the nature of the said invention for "IMPROVEMENTS IN OR RELATING
TO STEAM BOILERS AND IN SUPER HEATERS THEREFOR to be as follows:-
"
That a good deal of the water is sucked out of boilers into cylinders, thereby still
further increasing the quantity accumulating as a consequence of the process of
condensation, is a fault admittedly attaching to railway and tramway engines. It
necessitates an undue consumption of fuel and operates as a drawback upon the
working and the safety of locomotive engines; but above all does it become a
disturbing element in the working of tramcar engines. Now the degree of temperature
of the heating gases in their passage outwards from locomotive engines will afford us
a means of remedying this evil and effecting a notable saving in fuel. In the present
invention the steam, before reaching the cylinders, is dried by the heated gases of
the furnace which are made to pass through the tubes of a superheater that is
introduced in lieu of a funnel or else stands enclosed by the funnel. While the
stean is running through these tubes, it is dried and superheated partly from coming
in contact with the tubes and partly by the heat radiating from the superheater.
The steam as it issues from the boiler passes first by a non-return valve the
action of which will be described in the sequel, and thereupon enters the super-
heater. This latter, in the form of a tubular boiler, (its position being upright in
locomotive engines) is substituted in the room of a funnel, and in such case the
better plan is to carry it down to some extent into the smoke box. In stationary
boilers it is best fitted to the up-take or flues in any suitable position.
locomotive engines, the funnel encircles the superheater so that a portion only of
the beated gases shall pass along the annular space between the superheater and
the funnel or casing while the remainder will go through a heating pipe of the
superheater. Beyond the superheater, the funnel rises into the usual form.
In
The non-return or back pressure valve opening into the superheater from the
boiler which last may be fitted with horizontal boiler tubes in the usual way is
provided for the purpose of temporarily shutting off the steam, in the superheater,
from the generating water of the boiler, so that any water dragged in will serve to
saturate the steam in the superheater and thus a fresh generation of steam takes
place.

page_text: When the engine is started the steam will at once pass into the superheater by
lifting the valve. If there be equality of expansion in the superheater and in the
boiler the valve will close cutting off the steam in the superheater from the steam
in the boiler so that no saturation of steam from the water in the boiler can take
place. Then any water dragged along with the steam into the superheater will be
at once converted into steam while the steam itself will get superheated.
If, the steam being gradually consumed, the pressure in the superheater fall
below the degree of that in the boiler then the valve will open again and the
process will be repeated. The heat held by the superheated steam checks the
cooling process and prevents condensation from setting in. Hence the frequent
opening of the cylinder taps is dispensed with.
When locomotives are at a standstill or the pressure of the steam in the super-
heater has increased in intensity from any other cause, then the steam so soon as
the pressure exceeds a certain limit will return again from the superheater passing
by a second check valve which opens from the superheater in the direction of the
boiler. This second check valve may be therefore regarded as a safety valve for
the superheater. If lastly the superheating of the steam should reach such a pitch
as to threaten damage to piston and packing the injector provided and which may
be of varying construction will throw in some water into the superheater thus
bringing the steam nearer to the point of saturation again. In the present instance
the injector apparatus consists of an injector connected with the water tank by
means of a pipe and this injector has steam supplied to it from the dome of the
boiler by a pipe.
The steam when dried reaches the regulator through a pipe and passes from the
regulator into the cylinders while the exhaust steam escapes through the pipe
which may pass up the centre of the superheater and the funnel.

page_text: heaters therefor.
I MAX GEHRE, Engineer of Düsseldorf-Grafenberg, Prussia, 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:-
That a good deal of the water is sucked out of boilers into the cylinders, thereby
still further increasing the quantity accumulating as a consequence of the process
of condensation, is a fault admittedly attaching to railway and tramway engines.
It necessitates an undue consumption of fuel and operates as a drawback upon the
working and the safety of locomotive engines; but above all does it become a
disturbing element in the working of tramcar engines. Now the degree of
temperature of the heated gases in their outward passage from locomotive engines
will afford a means of remedying this evil and affecting a notable saving in fuel.
In the present invention the steam, before reaching the cylinders is dried by the
heated gases of the furnace which are made to pass through the tubes of a super-
heater that is introduced in lieu of a funnel or else stands enclosed by the funnel.
While the steam is passing through these tubes, it is dried and superheated partly
from coming in contact with the tubes and partly by the heat radiating from
the superheater.
The accompanying drawings represent an example of such a superheater applied
to a tram car engine. Figure 1 is a longitudinal section; Figure 2 is partly a plan
and partly a section; and Figure 3 a cross section.
The steam as it issues from the boiler passes first by a non-return valve a
Figure 1, the action of which will be described hereafter, and thereupon enters the
superheater c. This latter, in the form of a tubular boiler, (its position being
upright in locomotive engines) is substituted for the ordinary funnel; and in such
case the better plan is to carry it down to some extent into the smoke box e as
shown in the drawing. In stationary boilers it is best fitted to the up-take or
flues in any suitable position. In locomotive engines it will thus be seen, the
funnel or casing i encircles the superheater c so that a portion only of the heated
gases shall pass along the annular space between the superheater and the funnel or
casing, while the remainder will go through a heating pipe ƒ of the superheater.
Beyond the superheater, the funnel i rises into the usual form.
The non-return or back-pressure valve a opening into the super-heater from the
boiler which last may be fitted with horizontal boiler tubes in the usual way is
provided for the purpose of temporarily shutting off the steam, in the superheater,
from the generating water of the boiler, so that any water sucked in will serve to
saturate the steam in the superheater and thus a fresh generation of steam takes
place.
When the engine is started, the steam will at once pass into the superheater c by
lifting the valve a. If there be equality of pressure in the superheater and in the
boiler h, the valve will close, cutting off the steam in the superheater from the

page_text: steam in the boiler, so that no saturation of steam from the water in the boiler can
take place. Then any water drawn along with the steam into the super-heater will
be at once converted into steam, while the steam itself will get superheated.
If the steam being gradually consumed, the pressure in the superheater falls
below that in the boiler, then the valve a will open again and the process will be
repeated. The heat held by the superheated steam checks the cooling process and
prevents condensation from setting in. Hence the frequent opening of the cylinder
taps is dispensed with.
When locomotives are at a standstill or the pressure of the steam in the super-
heater c has increased from any other cause, then the steam, so soon as the pressure
exceeds the pressure in the boiler will return again from the superheater passing
by a second back pressure or return valve m Figure 1, which opens from the super
heater c into the boiler h. This second return valve m may be therefore regarded
as a safety valve for the superheater. If lastly the superheating of the steam
should reach such a pitch as to threaten damage to piston and packing, an injector
is provided, which may be of any suitable construction and which will introduce
water into the superheater, thus bringing the steam nearer to the point of saturation
again. In the present instance the injecting apparatus consists of an injector z
connected with the water tank by means of a pipe w, and supplied with steam from
the dome of the boiler by a pipe n.
The delivery pipe of the injecting apparatus which opens into the superheater is
marked with the letter s.
The steam when dried reaches the regulator r through the pipe d; and passes
from the regulator into the cylinders, while the exhaust steam escapes through the
pipe k which may pass up the centre of the superheater and the funnel i.
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
1. A superheater for railway and tramway engines consisting of a chamber such
as c located inside the funnel and having vertical tubes f in combination with the
back-pressure valve a Figure 1 which opens from the boiler into the superheater
the whole constructed and operating substantially in the manner and for the
purpose specified.
2. In combination with a superheater to dry the steam which passes into the
cylinders from steam boilers a back pressure valve such as a opening from the
boiler into the superheater for the purpose of cutting off the steam in the super-
heater from the boiler space and a return valve such as m to enable the steam from
the superheater to return into the boiler, whenever the pressure in the superheater
exceeds that within the boiler substantially as specified.
3. In an apparatus such as specified the combination with the superheater of
means substantially such as specified for saturating the steam in the said super-
heater.