New or Improved Means or Devices for Superheating Steam in Steam Boilers.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
New or Improved Means or Devices for Superheating Steam in
Steam Boilers.
I, WILHELM SCHMIDT, of Ballenstedt, A.II., in the German Empire, Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
-
Heretofore in order to superheat steam to as high a temperature as possible it
had been necessary to expose the superheaters to the action of intensely hot fire
gases, which increased the difficulty there is found in providing such superheaters
and in regulating the temperature at which this superheating takes place.
Moreover, the superheaters which were generally built in the flues occupied a
considerable space and thus formed an obstacle to the free passage and hence to
the proper utilization of the fire gases for the generation of steam.
The object of this invention is to provide steam superheating means wherein the
superheaters are built in proximity to the fire bridge of the steam boiler furnace
and can be connected therewith, these superheaters being capable of withstanding
the action of intensely hot fire gases so that the superheating may be effected at
any suitable temperature while preserving the superheater. which occupies as
restricted a space as possible and generating steam under the most favorable con-
ditions. For this purpose it is important to arrange the different sections of the
superheater in such a manner that the whole set of tubes form a flat body and
that the hot fire gases shall not strike these sections perpendicularly but shall
impinge more or less horizontally upon the surfaces formed by the row of sections;
furthermore these superheaters are so placed in the passage of the hottest fire
surfaces serve
gases that their upper
not only as highly protected
heating surfaces but form likewise conducting surfaces for the proper
utilization of the heat from the fire gases used for generating steam.
Lastly the regulation of the superheating is rendered simple and safe and
the branching off of the more or less voluminous flow of the fire gases whereby
such superheating is effected is led back after having impinged on the super-
heating surfaces along the shortest route in order to serve again for the generation
of steam.
In the accompanying drawings figs. 1 to 3 show two different ways of carrying
my invention into practice. According to the arrangement shown in fig. 1. a
strong plate a of cast metal is arranged behind the fire bridge wherein canals are
formed through which passes the steam generated in the boiler. These canals
are formed of forged iron pipes cast in the said plate. When the plate a is placed
at a certain interval from the fire bridge, the fire gasses can freely impinge upon
the former as well as upon the latter.
A damper be which can be operated by the stoker regulates the flow of the
fire gasses which heat the plate from below. The rod r which extends to the
stoker's stand is sufficiently low down to be cooled by the tube plate which is in
close proximity thereto and is surrounded with water. The damper be placed on
the lower surface of the tubes is thereby cooled, which suffices in connection

page_text: with the fact that the plate be is located at the rear end of the superheater a,
to prevent this damper from becoming red hot.
Fig. 2. shows an arrangement for steam generators provided with water
tubes. In this case the superheater a¹ is suspended behind the fire bridge, which
arrangement is particularly adaptable when a very high temperature is required
while the superheating can be regulated easily and safely and the fire gases can
return for the purpose of generating steam. This regulation is effected by shifting
the plate d resting on a row of boiling tubes and when this plate is drawn back as
shown in fig. 2. the gases escape upwardly in the direction indicated by the arrow
(heating up position) while if their passage is throttled or entirely closed as
in fig. 3. the gases escape in corresponding quantity below through the fire bridge
canal and impinge on the sides which serve as superheating means in order to
impinge at their subsequent ascent upon the water tubes. Fig. 3. shows more-
over the arrangement of a second superheater a lining the fire bridge. Obviously
the opposite wall of the fire bridge canal could be likewise covered with a super-
heater, or the first superheater a' could be made solid and in some cases flat
superheaters could be used so long as they allowed the gasses to travel in the
manner above set forth.
Dated this 5th day of March 1807
DE KATOW & Co.,
Agents for the Applicant.
New or Improved Means or Devices for Superheating Steam in
Steam Boilers.
I, WILHELM SCHMIDT, formerly of Ballenstedt on the Harz, in the German
Empire, at present of Wilhelmshöhe, near Cassel, in the German Empire, Civil
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:.
Heretofore in order to superheat steam to as high a temperature as possible it
has been necessary to expose the superheaters to the action of intensely hot fire
gases, which increased the difficulty there is found in providing such superheaters
and in regulating the temperature at which this superheating takes place.
Moreover, the superheaters which were generally built in the flues occupied a
considerable space and thus formed an obstacle to the free passage and hence to
the proper utilization of the fire gases for the generation of steam. The
object of this invention is to provide steam superheating means wherein the
superheaters are built in proximity to the fire-bridge of the steam boiler furnace
and can be connected therewith, these superheaters being capable of withstanding
the action of intensely hot fire gases, so that the superheating may be effected at
any suitable temperature while preserving the superheater, which occupies as
restricted a space as possible and generating steam under the most favorable con-
ditions.
For this purpose it is of paramount importance to arrange the different sections of
the superheater in such a manner that the whole set of tubes forms a flat body and
that the hot fire gases shall not strike these sections perpendicularly but shall
impinge more or less horizontally upon the surfaces formed by the row of sections;
furthermore these superheaters are so placed in the passage of the hottest fire
gases that their upper surface serve not only as highly protected heating surfaces

page_text: but form likewise conducting surfaces for the proper utilization of the heat from
the fire gases used for generating steam.
Lastly, the regulation of the superheating is rendered simple and safe and
the branching off of the more or less voluminous flow of fire gases whereby
such superheating is effected, is led back after having impinged on the super-
heating surfaces along the shortest route in order to serve again for the generation
of steam.
In the drawing left with provisional application figures 1-3 show two different
ways of carrying my invention into practice. According to the arrangement
shown in figure 1 a strong plate a of cast metal is arranged behind the fire
bridge wherein canals are formed, through which pass the steam generated in
the boiler. These canals are formed of forged iron pipes cast in the said plate.
When the plate is placed at a certain interval from the fire bridge, the fire
gases can freely impinge upon the former as well as upon the latter.
A damper which can be operated by the stoker regulates the flow of the
fire gases which heat the plate from below. The rod which extends to the
stoker's stand is sufficiently low down to be cooled by the tube plate which is in
close proximity thereto and is surrounded by water. The damper be placed on
the lower surface of the tubes is thereby cooled, which suffices in connection
with the fact, that the plate bc is located at the rear end of the superheater a,
to prevent this damper from becoming red hot.
Figure 2 shows an. arrangement for steam generators provided with water
tubes. In this case the superheater a is suspended behind the fire bridge, which
arrangement is particularly adaptable when a very high temperature is required,
while the superheating can be regulated easily and safely and the fire gases can
return for the purpose of generating steam. This regulation is effected by shifting
the plate & resting on a row of boiling tubes and when this plate is drawn back as
shown in figure 2, the gases escape upwardly in the direction indicated by the
arrow (heating up position) while if this passage is throttled or entirely closed,
as in figure 3, the gases escape in a corresponding measure below through the
fire bridge canal or channel and impinge on the sides which serve as superheating
means in order to impinge at their subsequent ascent upon the water tubes.
Figure shows, moreover, the arrangement of a second superheater a² lining
the fire bridge. Obviously the opposite wall of the fire bridge canal could be
likewise covered with a superheater, or the first superheater a could be made
solid and in some cases flat superheaters could be used so long as they allowed the
gases to travel in the manner above set forth.
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 superheating-means or devices for steam boilers, in which the employment
of intensely hot fire-gases, and a good exhaustion of the heat of said gases for
the generation of steam, is attained by the arranging of flat superheating bodies,
through which the steam of the boiler passes, and which are built into the flues
of the boiler near to the fire-bridge of the furnace, in such manner, that the
surfaces of said superheating bodies form, partly or wholly, conducting-surfaces
for the fire-gases, or parts of the walls of the flues, respectively, substantially
as described.
2. A form of construction and arrangement of superheating-means as afore
claimed, especially intended for steam-boilers with water-tubes, in which the
superheating-bodies are arranged to line the walls of, or form conducting channels
or tongues in the fire-bridge flue, said arrangement being such, that a current of
fire-gases deviated in any desired strength from another current, by means of a
regulating-device, is caused to wash said superheating bodies, before it is per-
mitted to return to the water-tubes for washing the same, substantially as
described.

page_text: 3. A form of construction and arrangement of superheating-means for steam-
boilers, as afore claimed, more especially intended for a flame tube boiler, in which
a superheating body (a) is arranged behind the fire-bridge, in such manner, that
the fire-gases controlled or influenced by a damper (6) are caused to pass either
wholly over the upper surface of said superheating-body or surface (a), or more 5
or less also below the surface of the said body, substantially as described.
Dated this 4th day of December 1897.
WILHELM SCHMIDT,
By De Katow & Co.,
Of 7 Featherstone Buildings, Holborn, London, W.C.,
Engineers and Patent Experts.
Agents for the Applicant.