Improvements in Steam Generators.
Year: 1898

page_text: Date of Application, 12th Dec., 1898-Accepted, 4th Feb., 1899
COMPLETE SPECIFICATION.
Improvements in Steam Generators.
I, JOHANN BROTAN, of Railway Station Building, Landstrasse 103, Linz,
Upper Austria, Chief Engineer of the Imperial and Royal Austrian State Railways,
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 has reference to improvements in steam-generators, which are
applicable to locomotive, stationary high-pressure, ship, torpedo-boat, and port-
able engine steam-generators and also to those for motor road-vehicles. According
thereto the fire-box is composed of bent tubes which communicate with each
other and also with the water-space and the steam-space of the longitudinal
boiler, and which are arranged in close contact with one another and form a
closed arched surface which, in conjunction with the tube-plate of the longitu-
dinal boiler, encloses the fire-space above the grate in a box-like manner.
tubes thus form in their entirety a vertical boiler, which is enclosed by the outer
casing of the fire-box.
These
In the accompanying drawings, Figs. 1, 2 and 3 are respectively a longi-
tudinal section, a vertical cross-section, and a partial horizontal section of a
steam-generator provided with a fire-box of this kind Figs. 4, 5, and 6 are
separate views illustrating the attachment of the tubes to one another; Figs. 7,
8 and 9, 10, are longitudinal and cross sections, illustrating two different forms
of steam-collectors, and their connexion with the longitudinal boiler; Fig. 11
shows the connexion of fire-box tubes, each made in two parts, with the steam-
collector; and Figs. 12, 13, and 14 represent a further modification of the
generator shown in Figs. 1, 2, and 3, which will first be described.
The fire-box, which forms the vertical boiler St, and is connected with the
fire-tube boiler R, and with the steam-collector 1, is surrounded by an air-tight
jacket M, which is, however, not subjected to steam pressure, and can therefore
be made of thin metal plate.
Its walls are provided at their lower portions with an (angle-iron frame a,
which may either be horizontal or, as shown, be inclined towards the rear wall
of the fire-box. In this frame there is mounted, right and left, two bottom
pipes b, which are suitably bent and may either be closed, as shown, at their ends
located under the fire-door or be connected together at those ends so as to form
one pipe. The ends of the bottom pipe or pipes near the rear wall of the ver-
tical boiler are closed by cleaning unions c. The pipe or pipes (hereinafter
referred to as the bottom pipe) may, however, communicate with, the interior of
the longitudinal boiler R either direct or through a water-pocket.
The bottom pipe is provided on its upper side and along its whole length with
screwed unions u which are situated very close together; the unions, which are
situated symmetrically on both sides of the vertical central plane of the fire-box,
are connected in pairs by means of bent tubes d', de
which extend
upwards along the walls of the outer jacket M and along the arched top of the

page_text: same. The tube d, which is situated nearest to the longitudinal boiler R,
extends close along the tube-plate of the same, and leaves the fire-tube openings
2021 are
in the said tube-plate free. The next following tubes d², d.
situated close together, and their upper bent portions are made either all of the
same height to suit the form of the top of the jacket, or they are arranged, as
shown, gradually lower towards the front wall.
J
Along the front wall, the tubes are arranged in concentric rows, the innermost
one of which surrounds the fire-door opening. Spaces y and y₁ are left free
under the fire-door and at the rear wall of. the firebox, and are walled-up with
fire-bricks, but may be diminished or even entirely dispensed with, as illustrated
in Fig. 13, by suitably arranging the tubes.
The connexions are preferably effected by means of sleeve nuts having right
and left hand threads, or by packing, as with copper wire. The sleeve nuts are
screwed upon the ends (which may be contracted, as shown) of the fire-box
tubes d¹,
and upon the unions of the bottom tube. The sleeves can be
fixed in their tightened-up positions by means of screwed pins v. The fire-box
tubes may be simply expanded in the bottom pipe if suitable apertures, furnished
with proper lids, be provided in the opposite side of the bottom pipe.
For the purpose of preventing the fire-box tubes from being warped, and the
radiation of large quantities of heat to the exterior, the fire-box tubes are each
provided with two ribs r (Fig. 5), which are screwed or riveted to the adjacent
ribs of the adjacent tubes, with intermediate packings. When using rolled
tubes, they are provided with lugs (Fig. 4), which are welded or brazed thereto.
In the latter case the jointing is preferably effected in the manner shown in
Fig. 6, and is caulked moderately on both sides.
Each fire-box tube carries at its highest point a discharge-pipe e
or e¹, e², (3
leading to the forward head V of the steam-collector. The
discharge pipes e issuing from the front wall may be arranged to open into a
casing, which communicates with the water and steam space. The firebox-
tubes d, d..
may each be made in two parts and in that case each part will
be provided with a separate discharge-pipe e or be arranged to open direct into
the steam-collector or the forward head thereof, by suitably bending, the firebox-
tubes as illustrated in Fig. 11. The highest fire-line ff (Fig. 1) is deter-
mined by the highest places of contact of the firebox-tubes d', d³
etc.
Water is supplied from the water-pockets of the longitudinal boiler by means
of pipes h. The boiler can be completely emptied by means of pipes g which
branch off from the bottom pipe, and which lead to a discharge-cock t. When
the bottom pipe opens direct into the longitudinal boiler or into the water-pocket
thereof a water-discharge cock may be arranged on each side of the tube.
The grate is arranged in such a manner that its surface k, k¹ is situated above
the pipe couplings. A fire-screen such as hereinafter described may be mounted
upon the masonry of the rear wall y¹.
etc.,
The space between the walls of the jacket M and the tubes d¹, d². . . .
may either be filled up with non-conducting material, such as asbestos, slag-wool,
or kieselguhr, or be utilized for consuming smoke.
In the latter case, there are bored, at the places of contact of the firebox-tubes,
numerous small holes n (Figs. 4 and 5) which serve to connect the air space
between the wall of the jacket and the firebox-tubes, with the fire space. On
the two sides of the vertical boiler there are provided, above the frame a, two
slides or dampers S, which allow the outer air to enter between the jacket and
the tubes, and, after having been highly heated, to be blown into the fire in the
form of fine jets from all sides, the amount of air being regulated by the posi-
tions of the dampers. This air, which is drawn in through the damper aper-
tures g, and is highly heated by contact with the walls of the firebox-tubes,
effects the most perfect possible combustion of the smoke gases. To increase

page_text: this action, there is preferably provided a fire-screen the masonry of which is
built of hollow bricks, the recesses of which communicate with the air space z
situated behind the masonry, whilst their sides facing the grate are provided
with small holes.
The steam-collector D is preferably provided with a forward head V, into
etc. On this forward
which the steam is discharged by the tubes d¹, d²
head any suitable number of washing-out holes may be provided.
The steam-collector may also be provided with a dome, and may be either
and 2, or
mounted directly upon the longitudinal boiler R, as shown in Figs.
cylindrical and connected to the boiler R as shown in Figs. 7 and 8, or mounted
in saddle-fashion over the longitudinal boiler, as shown in Figs. 9 and 10.
The construction shown in Figs. 1 to 4 and Fig. 6 may be modified as shown
in Figs. 12, 13, and 14 so as to dispense with a separate steam-collector, the for-
ward head V being secured direct to the tube-wall of the fire-box, which, as in
the arrangement previously described, is surrounded by a jacket; in this modi-
fication, also, the lower portion of the wall of the forward head V forms part
of the wall of the firebox.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:
1. A steam-generator of the locomotive type with a water-tube fire-box, in
which the water-tubes d¹, d², d³ of the fire-box which are arranged close
against one another, and which may each be in two parts form-it may be with
the wall of the forward head of the steam-collector--a closed arched surface,
which abuts with the first tube d' close up against the tube-wall of the fire-tube
boiler, and which, enclosing the fire-door aperture with concentric rows of its
last tubes d18, 19
forms the front end wall of the fire-box, all of the
tubes of the fire-box arch being connected at the top with the steam-collector and
at the bottom by means of a bottom pipe b with the water-space of the fire-tube
boiler.
2. A steam-generator according to the preceding claim, in which for the pur-
pose of making tight joints between the tubes d¹, da, d³ of the fire-box, and for
the purpose of stiffening them, the tubes are screwed or riveted together by
means of ribs r or lugs 1, with interposed packings.
3. In a steam-generator according to Claim 1, the provision of holes n in the
abutting places of the tubes d¹, for the purpose of blowing fine heated
jets of air into the firebox to an amount that can be regulated by means of
dampers.
4. The improved construction of steam-generators hereinabove described with
reference to and shown in Figs. 1, 2, 3, 4, and 6; and the same as modified
according to Fig. 5, to Figs 7 and 8, to Figs. 9 and 10, to Fig. 11, or to Figs. 12,
13, and 14, of the accompanying drawings.
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.