Improvements in Water Tube Steam Generators.
Year: 1897

page_text: Date of Application, 5th July, 1897-Accepted, 2nd July, 1898
COMPLETE SPECIFICATION.
Improvements in Water Tube Steam Generators.
I, JAMES HERMANN ROSENTIAL, of 147, Queen Victoria Street, in the City of
London, 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 for its object to provide a water tube steam generator of
compact and simple construction for use chiefly in torpedo boats and similar
small craft, and generally in cases where comparatively small power is required.
The improved steam generator is composed of a longitudinal drum of approxi-
mately cylindrical form but having formed on or secured to its lower side tube
boxes suitably dished or pressed to provide flattened surfaces wherein orifices
are formed for the reception of the tubes composing the heating surfaces, said
tubes extending downwards at a suitable inclination to enclose a furnace situated
near their lower ends which are closed or plugged. Smaller tubes fitted within
the heating tubes and extending upwards into an independent and removable
tray in the steam and water drum are provided to ensure proper circulation of
the water. A feed water purifier discharges the feed in the form of spray into the
tray to which the upper ends of the inner tubes are attached, and thence the
water descends through the inner circulating tubes to the bottom of the heating
tubes through which it ascends into the drum.
The invention is illustrated by the accompanying drawings in which Figure 1
is a transverse vertical section and Figure 2 a longitudinal vertical section of one
modification of the improved steam generator in which the tube box of the drum
is formed with flat inclined surfaces for the reception of the tube ends. Figure 3
is a transverse vertical section and Figure 4 a longitudinal vertical section of the
upper part of another modification of the steam generator in which the tube box
is strengthened by pressing it to produce a stepped surface for the reception of
the tube ends. Figure 5 is a cross section of the drum and part of the tubes of
a modified construction of the steam generator in which the tube box is made in
two separate parts or sections riveted to the underside of the drum. Figure 6
is a similar view of the lower part of the drum showing a modified construction
of the tube box as made in two parts.
Referring to the modification shown at Figs. 1 and 2 the improved steam
generator comprises a steam and water drum A of cylindrical form the underside
of which is cut and has secured under the opening a tube box B formed by dishing
or pressing a plate or plates to the contour shown. From this tube box B a num-
ber of rows of water tubes C depend at an inclination on each side of the vertical
centre so as to enclose at their lower ends a furnace D extending the full length
of the boiler. The furnace grate is enclosed by bridges E extending lengthwise of
the boiler on both sides, and by brickwork or other walls F which serve to
close the ends of the boiler and in one of which is formed the fire door opening F¹,
the bridges and end walls being carried by supporting brackets G which rest upon
a trough-like base H into which the water of the boiler may be run and drained
off when emptying the boiler. Upon this base piece H is carried a suitably lined

page_text: casing I serving to enclose the furnace and water tubes, thus forming a combus-
tion chamber and also serving to support the drum A which is secured to it by
angle iron or like bars J. The water tubes C of the steam generator are closed
at their lower ends by screwed caps or plugs c which may be removed for empty-
ing the boiler; and within these tubes are fitted smaller open-ended tubes C¹
which do not reach the lower ends of the larger tubes but extend through their
upper ends and are secured by screw nuts or otherwise to a tray K supported
within the drum A. Over this tray or a smaller tray placed over it, the feed
water is discharged in the form of spray, and the impurities in the water are thus
deposited in the tray from which they may be periodically blown off through a
pipe fitted with a cock. The fire gases arising from the furnace D pass upwards
among the water tubes and are directed through the spaces between them by
means of baffle plates L and after parting with their heat they pass to the
chimney M. Circulation of the water within the water tubes C is facilitated by
means of the internal open ended tubes C¹ which latter are held centrally within
the larger tubes.
The modification represented at Figures 3 and 4 differs from that above
described in respect that the plate forming the tube box B secured to the under-
side of the drum A is pressed to the zig-zag or stepped form shown, in order to
strengthen it; and the tubes C are arranged in groups for each ridge and depres-
sion of the tube box, whilst the ends of the furnace chamber are enclosed by
tubes..C.
In the modifications represented at Figures 5 and 6 two separate tube boxes B
suitably dished to present a tube plate at right angles to the inclined water
tubes C, are attached to the underside of the drum which is of cylindrical form.
The tube boxes may be straight in the direction of their length or they may
be stepped in the manner shown in Figure 4, and the two parts may be flanged
inwards and connected together as shown at Figure 6.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is:-
A water tube steam generator composed of a cylindrical drum having attached
to its under side a tube box or boxes dished or pressed to present a flattened or
stepped tube plate or plates in which are secured depending inclined water tubes
arranged to enclose the furnace, circulation being ensured by a system of internal
circulating tubes extending downwards into the heating tubes and fixed in an
independent and removable tray into which the feed water is distributed.
Dated this 3rd day of July 1897
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62, Saint Vincent Street, Glasgow,
Agent for the Applicant."