Improved Steam Jet Device for Smoke Consuming Furnaces.
Year: 1896

page_text: Date of Application, 9th Nov., 1896-Accepted, 9th Jan., 1897
COMPLETE SPECIFICATION.
Improved Steam Jet Device for Smoke Consuming Furnaces.
I, FRANZ MARCOTTY, of 6 Nesselbeck Strasse, Berlin, in the Empire of
Germany, Merchant, 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 :-
In smoke consuming furnaces, the construction of which is based on the principle
of a steam jet system arranged above the grate, it is absolutely necessary that two
conditions be fulfilled if the desired effect is to be properly attained.
Firstly the sheet or body of steam produced by the jets must always be
maintained at a certain desired distance above the grate or above the upper surface
of the layer of fuel in process of combustion, since the effect of the steam on the
soot, and highly carbonized hydrocarbons to be consumed, is not uniform at various
heights above the fuel and the desired result will not be attained if the position of
the said sheet or layer of steam be either too low or too high.
Secondly, care must be taken that the series of jets employed to produce the
said sheet or body of steam be so distributed that no spaces occur, through which
a considerable part of the gases or products of combustion might escape, without
being brought into contact with a sufficient body of steam.
The first of these two requirements has been met in practice by fixing the steam
nozzles in the boiler. This arrangement however causes an un-economical working
of the furnace since it is necessary to keep steam blowing through the nozzles when
the boiler is not at work, which is very often in the case of locomotives, in order
to prevent the nozzles from being burnt or melted off. The second condition
however is not provided for by this arrangement, as it does not permanently admit
of the proper distribution of the steam jets. This is due to the fact that in this
class of furnace, the steam nozzles are always arranged in the fire box, so that they
are constantly exposed either directly to the fire or to the radiated heat therefrom.
The consequence is that when lighting the fire, say of a boiler, the nozzles will
become very black and their openings partially clogged with soot.
This condition is intensified by getting up steam because steam condenses in the
pipe leading to the steam nozzles and this is forced with steam into the nozzles and
vaporizes there.
This tends to cause a scale formation at the nozzle openings and combines with
scum forced up by the steam and with the soot and forms a hard pasty mass. The
stopping up of the jet nozzles may also be due to other causes, thus the borings
produced by drilling the nozzles may be forced back into the openings by the
steam, or impurities such as cinder dust and the like may be blown into the nozzle
penings by the steam.
Owing to these circumstances, the steam jets soon become unequal or the direction
of spray is altered by partial stoppage of the passages, some of which may become
entirely stopped up, thus rendering the consumption of smoke very defective.
The clogging of the nozzles continues until the steam can find no outlet at all,
whereon the nozzles will be entirely burnt up owing to the failing of the steam to
ool the same.
The jet nozzles will also become injured when the attendant turns off steam
rom the nozzles by way of economy at the time when steam is not required for '
unning the engine.

page_text: The above reasons render the extensive introduction of furnaces of the class
described into practice an impossibility and gas and half gas furnaces have been
resorted to in order to attain a reliable and undisturbed smoke combustion.
The object of the present invention is to obviate the above mentioned
disadvantages in connection with furnaces of the class specified by a simple and
novel construction of the steam nozzles. This object is attained by connecting
the nozzles revolubly to the steam feed pipe and providing means whereby the
same may, without trouble, and at any time even during the working of the furnace.
be withdrawn from the influence of the fire. Stops are provided in order to
ensure the return of the jet nozzles to their proper position when they are to be
employed..
In order to enable the invention to be readily understond I will describe the
same with reference to the accompanying drawing in which the same letters of
reference indicate like parts in all the figures.
Fig. 1 is a longitudinal section of part of a boiler with the present invention
plied thereto.
Fig. 2 is a section through the attachment for the jet nozzles and
Fig. 3 is an exterior view drawo at right angles to Fig. 2.
In the construction shown the nozzles are represented to extend over the back
the fire bridge into the combustion chamber. It will however be clear that the
same may, if desired, be arranged at the sides, or at any point according to the
construction of the fire box.
In the arrangement illustrated, the jet nozzles are mounted in such manner as
to cause the steam to be turned off automatically when the nozzles are pulled back
out of operation while the steam is turned on as soon as the said nozzles are
replaced in their operative position.
The advantage of this arrangement is that as long as the nozzles are exposed to
the fire within the fire box, steam will be fed to the same thus cooling them and
preventing them from becoming destroyed or damaged by the fire.
Thus inattention on the part of the firemen cannot result in damage to the jet
nozzles.
The particular arrangement of the device shown is as follows :-
Below the grate g two rails f f are fixed which serve to guide the nozzle and
the steam pipe, which rails are curved or bent upwards at the rear end of the
grate.
The pipe a carrying the jet nozzle is mounted in the plug b of a cock which is
adapted to turn in a shell d, which latter is in communication with the steam
pipe c. The plug and also the pipe connection a are both mounted on rollers e. el
adapted to run on the rails f.f. The tube a is further provided with an outwardly
projecting hook i adapted to engage a stop 4, mounted within the fire box, when
the nozzle is pushed up into the combustion chamber.
Close to the nozzle head is fixed an arm m adapted to rest against the rear of
the fire bridge n when the apparatus is in operative position so as to place the
nozzle always in the same direction.
The end of the steam pipe c is detachably connected by means of a coupling o
to the main feed pipe p, which may either be flexible, jointed pipe, asbestos tubing
or the like, or fixed according to requirement. In order to prevent too much air
from passing through the ash pit and upwardly underneath the rear end of the
grate a door q is arranged which prevents the access of the air at this point. This
door may be opened or closed by the firemen, when the jet nozzle is to be withdrawn
by any suitable means.
The action of the device is as follows :-In order to bring the nozzle into its
operative position in the combustion chamber, the whole device is pushed along the
rails f. f.
During the latter part of the movement the rollers e' will ascend the curved or
or bent part of the rails until the hook i engages the stop h and the stop m strikes
against the rear of the fire bridge. Thus the position of the nozzle and with it

page_text: that of the sheet or body of steam over the grate will always be retained in a
certain predetermined relation to the grate.
The movement of the carriage in ascending the curved or bent ends of the
rails ff will open the steam passage allowing steam to pass to the nozzle as
soon as the latter has attained its position in the combustion chamber.
The carriage with the feed connection and the nozzle may be retained in its
operative position by any suitable means, not shown in the drawings, to prevent
any accidental displacement of the same.
In withdrawing the device from its operative position, the above described
movements take place in the reversed order i.e. on withdrawing the pipe the
carriage will descend the curved or bent ends of the rails ff thus turning
off the steam by the rotation of the plug in the shell d as previously
indicated.
By means of the above described device the nozzle may be withdrawn from
the combustion chamber at any time, in order to inspect the orifices in the same,
or if necessary to clean them and thus to always secure a proper distribution of the
steam jets, whilst the boiler is being heated. In the case of boilers which work
periodically the nozzle may be withdrawn from the combustion chamber during
the periods of rest, by which means a considerable saving in steam will be effected,
in comparison with furnaces having fixed steam distributors. Thus in the case of
a reserve locomotive, the amount of steam consumed per hour by a fixed steam
distributor of the ordinary construction, is about 40 kilogrammes, this means a
surplus consumption of about one hundredweight of good coal per day of eight
working hours.
This amount of coal would be saved by employing the steam distributor
constructed according to the present invention.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In smoke consuming furnaces having a series of fine steam jets sprayed over
the grate, a steam spraying device having the jet nozzle revolubly connected to its
steam feed pipe and provided with stops, in order to enable the withdrawal of the
said nozzle from and its replacement in operative position to be readily effected
during the working of the furnace, substantially as described.
2. In a device of the character herein described the connection of the nozzle to
its steam feed pipe in such manner that one part is attached to the shell and the
other to the plug of a cock, so that the withdrawal of the nozzle from the com-
bustion chamber will effect an automatic shut off of the steam supply, which will
be re-opened automatically on returning the said nozzle to its operative position,
substantially as described."
3. The combination with the device referred to in the above claims of guide
rails arranged below the grate longitudinally of the fire box in such manner
that when the nozzle asceuds the upturned ends of the rails, it shall be
turned relatively to the steam feed pipe so as to open the steam supply auto-
matically and close it at the descent of the nozzle, substantially as herein
described.
4. The improved steam jet device for smoke consuming furnaces constructed and
operating substantially as herein described and for the purpose stated.
Dated November 9th 1896
HARRIS & MILLS,
23 Southampton Buildings, W.C., Agents.