Improvements in Steam Boilers.
Year: 1899

page_text: Date of Application, 10th Aug., 1899-Accepted, 16th Sept.,
1899
COMPLETE SPECIFICATION.
Improvements in Steam Boilers.
We, JOHN BROKENSHIRE FURNEAUX, of Victoria Works, Gateshead-on-Tyne,
in the County of Durham, Engineer, and WILLIAM ARMSTRONG WOODESON, of
Victoria Works, aforesaid, 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:-
This invention has reference to an improved construction of vertical tubular
boiler as we shall now describe with reference to the accompanying illustrative
drawings wherein Fig. 1 shows the improved boiler in central vertical section
and Fig. 2 in horizontal section on the line A A of Fig. 1.
The boiler comprises a cylindrical shell 1, a centrally arranged fire box 2 of
truncated conical shape fixed in the lower part of said shell, a central cylindrical
flue tube 3 carried by the fire box and extending up through the water space
of the boiler, and a centrally arranged chimney 4 extending from the top of
the flue tube. The shell 1 and flue tube 3 are connected together at intervals
all around or nearly all around the same by horizontal or nearly horizontal straight
fire tubes 6 that are arranged one above the other and communicate at their
inner ends with the flue tube 3 and at their outer ends with a smoke box 7
formed by an annular casing 8 that surrounds the shell 1 for a portion of its
height. Within the flue tube 3 is a slab or plate 9 of refractory material such as
fire clay that serves to divide the flue tube horizontally into two parts and to
baffle and deflect the hot product of combustion, or the greater portion thereof,
coming from the firebox, and cause them to flow outward through some of the
tubes 6 into the smoke box 7 from which they return through the remaining
tubes 6 into the upper part of the flue tube 3 whence they flow direct to the
chimney 4. This slab or plate 9, which is of circular shape, may conveniently
consist of a disc of a size to pass through the top of the fire box and be formed
with notches 9" to admit of its being passed upward above supporting lugs 10
so that upon then being partly turned about a vertical axis it can be caused to
rest upon the said supporting lugs which may be short lengths of tube fixed in
the inner ends of some of the tubes 6. To ensure complete combustion of the
products of combustion, air may be admitted from the external atmosphere to
the flue tube 3, both below and above the refractory slab or plate 9, by air
supply tubes. In the example shown, bent tubes 11 extending through the
bottom of the smoke box 7 and into some of the lower tubes 6 serve to admit air
to the flue tube 3 below the slab or plate 9, whilst other tubes 11ª extending
horizontally through the smoke box into some of the upper tubes 6 serve to admit
cool air to the upper part of the flue and directly over the slab or plate 9.
As will be seen from Fig. 2, a space 12 unoccupied by tubes 6 is left at one
side of the boiler to enable access to be gained to the exterior of the conical fire
box 2 and some of the tubes 6 for cleaning purposes. A similar space unoccupied
by tubes may be provided at the opposite side of the boiler so as to give further
facility for cleaning the outside of the tubes. The outer casing 8 may con-
veniently consist of circularly bent plates arranged to slide in concentrically

page_text: arranged grooves 8* formed in annular top and bottom plate 8b, 8°, secured to the
shell 1, the arrangement being such that any one of the plates comprising the
casing can be moved round in its groove to allow of ready access being gained
to the tubes 6 for cleaning them or for other purposes. The air tubes 11° are
made readily removable to enable the plates through which they extend to be
moved when desired.
13 is an inclined water tube, of comparatively large cross-section, extending
across the upper part of the fire box 2. This tube serves to promote circulation,
to increase the heating surface, and to baffle the flame and hot gases and prevent
them passing too quickly through the fire tubes 6.
By ine construction described a boiler having a large heating surface and good
water circulation can be produced in a simple and convenient manner,
whilst by
the use of the slab or plate 9 and the admission of air to the upper and lower
parts of the flue tube 3, practically complete combustion of the hot gases can be
ensured.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is: -
1. A vertical boiler having an outer smoke box and an inner flue tube that
extends centrally upward from the fire box, is connected to the outer shell of the
boiler by fire tubes, and is divided by a horizontal plate of refractory material
into upper and lower parts, the arrangement being such that the hot gas and
products entering the lower part of the flue tube are caused to flow outward
through some of the fire tubes into the smoke box and then to flow inward through
the remaining tubes into the upper part of the flue tube and thence to the
chimney extending from the top of the flue tube, substantially as described.
2. The improved vertical tubular boiler constructed, arranged and operating
substantially as described and shown.
Dated this 10th day of Avanot 1800.