Improved Devices for Preventing the Deposit of Ashes in Boiler Furnace Flues, and for the Consumption of Smoke.
Year: 1894

page_text: COMPLETE SPECIFICATION.
Improved Devices for Preventing the Deposit of Ashes in Boiler
Furnace Flues, and for the Consumption of Smoke.
I, EMIL ERPFF, of 221, Prenzlauer Allee, Berlin in the Kingdom of Prussia,
German Empire, Manager, 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:-
This invention relates to a device for preventing the deposit of ashes in boiler
flame-tubes, and for intensely mixing the furnace-gases with air within the same,
and consists generally in arranging within said tubes shields by means of which the
free section of the flame-tubes is diminished and, consequently, a stronger draught
of air is produced. I prefer to arrange these shields in such a manner, that the
draught is strongest at the lower portion of the flame-tube or tubes, as will as more
fully described hereinafter.
Referring to Fig. 1, a is a vertical section through the shield, the latter having
in the whole the configuration of a scythe the convex side of which is directed
upwards. This shield is made in one casting with a tongue a' at its lower portion,
and is held within the flame-tube 6 by special feet c supported directly by the wall
of tube b. These feet are provided with curved slots c', through which take
the bolts a² of shield a. By aid of this arrangement, the feet may be adjusted to
fit into flame-tubes of different diameter, and also the position of the shield within
a given flame-tube may be altered or adjusted, i.e. the shield may be raised or
lowered, so that the strength of draught in the upper or lower portion of the flame-
tube may be regulated thereby.
I prefer to arrange these shields in the flame-tube in such a manner, that the
position of the consecutive shields is alternately higher and lower, so that the
greater part of the air is compelled to flow in a zig-zag way, which I have found
by experience to be of high efficiency with regard to the prevention of the deposit
of ashes, as well as to the intense mixing of the fire-gases with air.
Instead of providing the shield with a fixed tongue (a'), I may arrange the latter
also movably, so that the free section of the flame-tube below each shield may be
altered or regulated by altering the position of the movable tongue.
When using
this arrangement, I prefer to make the shield proper and its feet in one piece,
as shown in Figs. 2 & 3, in which a is the shield proper and a the movable
tongue secured to the former by hinges d. The line of separation between the
shield proper and its tongue is covered by a strip e of metal fixed by rivets to
the part a. The upper rim a of tongue a is bent rearwards in such a manner,
that at each position or inclination of the tongue the proper closure between the
said rim and said strip e is maintained. A chain is attached to the lower rim
of tongue a, by means of which former the latter may be raised or lowered;
the upper links of said chain may be coupled with a hook y fixed to the shield,
so that the respective position of the tongue is maintained thereby.
It will sometimes be necessary to raise or lower the movable tongue or
tongues whilst the boiler is at work. In this case I replace the hook g, Figs. 2
& 3, by a roller h, Figs. 4 & 5, and I then connect the several vertical chains f
with a horizontal chain i, by means of which all the tougues may be adjusted
simultaneously.
In order to employ the shields also for effecting a better combustion of smoke,
I may combine them with a special air-pipe leading air into the front-part of
the flame-tube, that is to say, into the part directly behind the fire-bridge.

page_text: I have shown this arrangement in Figs. 6-8, in which k is the afore-
mentioned air-pipe, which is held by the shields a. The front-shield, behind
which pipe is terminating, consists of two parts a' a³, which latter contains a
number of parallel slots that are covered in some distance by the other shield-
part a'. The air flowing through pipe k in a direction contrary to that of the
gases within tube 6 is intensely heated in the long pipe, so that the hot air on
leaving pipe k, entering tube b, and mixing with the furnace-gases effects a
thorough combustion of the unburned particles still contained within, and conveyed
by, the latter.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a boiler flame-tube, a shield, adapted to prevent the deposit of ashes
within said tube by diminishing the free section of the latter, and increasing the
draught thereby, substantially as described.
2. In a boiler flame-tube, a shield, adapted to prevent the deposit of ashes
within said tube by diminishing the free section of the latter, and increasing the
draught thereby, said shield having adjustable feet adapted to support the former
in flame-tubes of different sizes, substantially as described.
3. In a boiler flame-tube, a shield, adapted to prevent the deposit of ashes
within said tube by diminishing the free section of the latter, and increasing
the draught thereby, said shield having a movable ongue a adapted to be raised
or lowered, and to alter the draught thereby, substantially as described.
4. In a boiler flame-tube, a shield, adapted to prevent the deposit of ashes
within said tube by diminishing the free section of the latter, and increasing the
draught thereby, said shield having a movable tongue a (Figs. 2 & 3) adapted
to be raised or lowered, and to alter the draught thereby, said movement being
effected by a chain ffixed to the tongue and adapted to be booked to the
shield, substantially as described.
5. In a boiler flame-tube, shields a³, adapted to prevent the deposit of ashes
within said tube by diminishing the free section of the latter, and increasing the
draught thereby, said shields having movable tongues a adapted to be raised
and lowered by chains f fixed at one end to the tongues, and at the other end
to a chain (Figs. 4 & 5) adapted to effect a simultaneous adjustment of all the
tongues, substantially as described.
6. In a boiler flame-tube, shields a, (Fig. 6) adapted to prevent the deposit
of ashes within said tube by diminishing the free section of the latter, and
increasing the draught thereby, said shields carrying a pipe k adapted to lead
air into the fore-part of the flame-tube in a direction opposite to that of the
furnace-gases, and to heat that air by the latter, substantially as described.
7. In a boiler flame-tube, shields a (Fig. 6) adapted to prevent the deposit
of ashes within said tube by diminishing the free section of the latter, and
increasing the draught thereby, said shields carrying a pipe adapted to lead
air into the fore-part of the flame-tube in a direction opposite to that of the
furnace-gases, and to heat that air by the latter, the front-end of said pipe k
being covered in some distance by a shield a" (Figs. 7 & 8) having slots 1, the
latter being covered in some distance by a shield a', substantially as described.
Dated this 2nd day April 1904.
By Geo. H. Rayner,
EMIL ERPFF,
37, Chancery Lane, London, W.C., Agent for the Applicant.