Improvements in the Draught Inducing Apparatus and Arrangements of Steam Boilers of the Locomotive Type.
Year: 1894

page_text: Date of Application, 13th Nov., 1894
Complete Specification Left, 13th Aug., 1895-Accepted, 14th Sept., 1895
PROVISIONAL SPECIFICATION.
Improvements in the Draught Inducing Apparatus and Arrangements
of Steam Boilers of the Locomotive Type.
I, ROBERT WEATHERBURN, of 93 Highgate Road, Kentish Town, London, N.W.
Engineer, do hereby declare the nature of this invention to be as follows:-
:-
The object of my invention is to produce a more efficient draught through the
flue tubes of steam boilers of the locomotive type, than has been usual when
employing an ordinary arrangement of blast pipe in the smoke box the exhaust
steam blast as heretofore applied having been found in some cases inadequate to
the production of an efficient draught through the whole of the flue tubes and
For the
especially those located furthest from the longitudinal axis of the boiler.
purpose mentioned I arrange the blast pipe with its steam outlet at or near (it may
be somewhat below) the level of the horizontal plane containing the axes of the
middle row of tubes, and above the blast pipe provide a second pipe having its axis
in line with the axes of the blast pipe and of the chimney and so arranged as to
form an annular way between itself and the lower part of the chimney and
to receive the steam jet and current of gases thereby induced which as they rise
from the upper end of the second pipe into the chimney induce a second current of
gases to flow through the annular space into the chimney, the object being to
diffuse or generalize the draught and distribute it amongst and through the tubes
and control the speed of the effluents as may be desirable. The second pipe may
have the form of a hollow cylinder or frustum of a cone or conoid and may with
advantage be bell-mouthed or equivalently shaped at its lower end, its upper end
extending into but not touching the lower part of the chimney, and its lower end
down to the level of the second or third row of tubes from the top or thereabout.
In some cases a third pipe is provided somewhat larger in diameter than that above
referred to as the second so as to form a third or subsidiary annular current and
this hood pipe is or may be adapted to be lifted or lowered at will by means of
guides and levers worked from the driver's stand. In this modification when the
hood pipe is raised the exhaust steam passes through a secondary orifice the annular
space being also increased by such movement and the draught through the flue tubes
is thereby altered.
According to another plan the second pipe is adapted to slide up or down or to be
connected to the hood pipe so that both work together.
lu order further to increase the draught inducing efficiency of the apparatus I in
some cases make the blast pipe of a more or less oblong or flattened form in cross
section for a part of its length and at the orifice and may make the second pipe
(also the third pipe when such is used) of similar cross sectional form.
For increasing the velocity of the gases I provide for a reduction of the area of
the blast pipe orifice without altering its height. One arrangement for this
purpose comprises a ring of bevelled form in cross section adapted at its onter
circumference to fit within the orifice of the blast pipe and so mounted that it can
through rod and lever be worked from the driver's stand of a locomotive engine or
other convenient place so as to be placed and held within or moved and retained
clear of the blast pipe or it may be made to slide up or down similarly to the hood
pipe already mentioned, or in lieu of such a ring there may obviously be substituted
for reducing the outlet of the blast pipe to sharpen the blast when required any

page_text: other convenient form of device such as a square a round a conical or a triangular
block sharpened at the point or a cross shaped grid sharpened at its lower edges so
as to prevent the smoke striking or a small ring or a simple bar adapted to extend
straight across and within the blast pipe. As will be evident that part of my
invention having for object to diffuse and improve the draught can be used without
the means for sharpening the blast and vice versa.
Dated this Thirteenth day of November 1894.
Improvements in the Draught Inducing Apparatus and Arrangements
of Steam Boilers of the Locomotive Type.
I, ROBERT WEATHERBURN, of 93 Highgate Road, Kentish Town, London, N.W.
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 :-
The object of my invention is to produce a more efficient draught through the
flue tubes of steam boilers of the locomotive type, than has been usual when
employing an ordinary arrangement of blast pipe in the smoke box, the exhaust
steam blast as heretofore applied having been found in some cases inadequate to
the production of an efficient draught through the whole of the flue tubes and
especially those located furthest from the longitudinal axis of the boiler. And in
order that the nature of my invention and the manner in which it may be
conveniently carried into practical effect may be fully understood, I will now
describe the same with reference to the accompanying illustrative drawings:
Referring to Figs. 1 and 2 (whereof the former is a transverse vertical section
in the plane of the chimney axis, and Fig. 2 is a plan with part of the boiler casing
removed,) A is the blast pipe, arranged with its steam outlet near the level of the
borizontal plane containing the axes of the middle row of tubes; B is a second pipe,
above the blast pipe, this second pipe B having its axis in line with the axcs of the
blast pipe A and of the chinney C, and being so arranged as to form an annular
way D, between itself and the lower part of the chimney C, and to receive the
steam jet and current of gases thereby induced, which, as they rise from the upper
end of the second pipe B into the chimney (', induce a second current of gases to
flow through the annular space into the chimney C; the object being to diffuse or
generalize the draught, and distribute it amongst and through the tubes E, anl
control the speed of the effluents as may be desirable. The second pipe, B, is
represented as a hollow frustum of a cone, but it may have the form of a hollow
cylinder, or be otherwise formed; and, in some cases, may with advantage be bell-
mouthed or equivalently shaped at its lower end. Sometimes, in order further to
increase the draught inducing efficiency of the apparatus, I make the blast pipe A
of a more or less oblong or flattened form in cross section for a part of its length
and at the orifice (see Figs. 3 and 4), and I may make the second pipe B (Figs. 3
and 4) (also the third pipe, when such is used, as hereinafter mentioned) of similar
cross sectional form.
As is well known, engines sometimes have downward extensions of the chimney
liners, extending some distance into the smoke boxes. Now Figs. 5 to 9 inclusive
illustrate modes of applying my invention in such cases. Holes F, of circular or
any other suitable shape, are formed through the wall of the downwardly projecting
portion of the lining. The second pipe, B, can be adapted to slide up and down,

page_text: (Figs. 11 & 13), or in a circular path as in the arrangements illustrated in Figs. 5
and 6, and in Fig. 7, respectively; the said pipe being attached to a perforate.l
guide B' that surrounds the projecting chimney lining and can be operated by ros
and bell crank lever (a. b. c.) from the driver's stand, so that the holes in the slite
and those in the projecting portion of lining will more or less coincide to regulate
the draught.
In Fig. 8 that part of the projecting portion of the chimney lining which is below
the holes F is made to constitute the second tube, B, and, in this particular example,
is bell-mouthed and has a perforated sliding ring B' with operating means a. b. c. as
before described. In some cases a third pipe is provided (G, Fig. 10) so as to form
a third or subsidiary annular current (at H). This third pipe may be fixed, as
shown, or it may be adapted to be lifted or lowered at will, by means of guides and
levers worked from the driver's stand. In this modification the exhaust steain
passes through the secondary orifice, G¹, and the annular space H can be increased
by the raising of the pipe G, whereby the draught through the flue tubes can be
altered. I sometimes connect the second pipe, B, and the third pipe, G, and ad ipt
them to be moved together. An example of such an arrangement is illustrated in
Figs. 11 and 12.
In this case the pipes B and G are provided with pins, I, that work in slots in a
fixed frame J, and are carried by two side bars, K, having pins, L, with which
engage the slotted ends of two lever arms, M, carried by a rock shaft, N,
adapted to be worked from the driver's stand. Figs. 13 and 14 show an arrange-
ment in which the pipes B and G are arranged to be separately adjusted. In this
case the vertically guided pins, I, of each pipe are arranged to be operated by the
slotted ends of a pair of lever arms, M, of a rock shaft N.
For increasing the velocity of the gases I provide for a reduction of the area of
the blast pipe orifice without altering its height. One arrangement for this purpose
(represented in Figs. 15 and 16) comprises a ring, K, of bevelled form in cross
section, adapted at its outer circumference to fit within the orifice of the blast
pipe, A, and so mounted that it can, through rod d and lever e, be worked from the
driver's stand of a locomotive engine, or other convenient place, so as to be placed
and held within, or moved and retained clear of, the blast pipe A; or it may be
made to slide up and down, similarly to the third pipe (G) already mentioned; or,
in lieu of such a ring, there may obviously be substituted, for reducing the outlet of
the blast pipe A to sharpen the blast when required, any other convenient form
of device, K, such as a square, a round, a conical, (Figs. 17 and 18) or a triangular
block, sharpened at the point, or a cross shaped grid (Figs. 19 and 20) sharpened
at its lower edges so as to prevent the steam striking; or a small ring or a simple
bar adapted to extend straight across and within the blast pipe.
In the drawings referred to in the foregoing description like or equivalent
parts are marked with the same letters of reference in each of the several
modifications.
As will be evident, that part of my invention having for object to diffuse
and improve the draught can be used without the means for sharpening the
blast, and vice versa.
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. A steam boiler of the locomotive type having in the smoke box thereof a
blast pipe and between it and the chimney a second pipe the arrangement being as
herein before described such that between the second pipe and the lower part of the
chimney there will be an annular way and that the said second pipe will receive
the steam jet and current of gases thereby induced and that as they rise from
within the upper end of the said pipe into the chimney a second current of gases
will be induced to flow upward around the exterior of the second pipe and into the
chimney as set forth.

page_text: 2. In a steam boiler of the locomotive type draught inducing apparatus of the
kind referred to in the preceding claim in which the blast-pipe is arranged with its
steam outlet at or near the level of the horizontal plane containing the axes of the
middle row of tubes, and the second pipe is located between the blast pipe and
chimney with its axes in line with the axes of the blast pipe and of the chimney as
described.
3. In the smoke box of a steam boiler of the locomotive type, draught inducing
apparatus such as referred to in Claim 1 having the second pipe adapted to slide
up and down as described for the purpose mentioned.
4. In the smoke box of a steam boiler of the locomotive type draught inducing
apparatus of the kind referred to in Claim 1 constructed as shewn in and described
with reference respectively to Figs. 5 & 6; Fig. 7 and Figs. 8 and 9 of the
accompanying drawings.
5. Draught inducing apparatus of the kind referred to in Claim 1 constructed
with a third pipe substantially as and for the purpose specified.
6. Draught inducing apparatus of the kind referred to in Claim 1 constructed
with a second pipe and a third pipe so connected that they can be worked both
together as described.
7. Draught inducing apparatus of the kind referred to constructed with the
blast pipe of a more or less oblong or flattened form in cross section for a part of
its length and at the orifice as described, and with the second pipe (also the third
pipe when such is used) of similar cross sectional form or not.
8. Draught inducing apparatus for a steam boiler of the locomotive type in which
there is combined with the blast pipe a movable device and means for operating
the same so that the area of the blast pipe orifice can be reduced at will for
increasing the velocity of the gases, substantially as described with reference to
the examples illustrated respectively in Figs. 15 and 16, Figs. 17 and 18, and
Figs. 19 and 20 of the accompanying drawings.
9. My improved draught producing apparatus constructed arranged and operating
as described with reference to and illustrated respectively by Figs. 15 & 16, Figs. 17
& 18, and Figs. 19 & 20 of the accompanying drawings.
Dated this 13th day of August 1895
ROBERT WEATHERBURN.
W. Lloyd Wise,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.