Improvements in and relating to Steam Boilers.
Year: 1890

page_text: Date of Application, 1st Apr., 1890-Accepted, 10th May, 1890
COMPLETE SPECIFICATION.
Improvements in and relating to Steam Boilers.
I, NATHAN PRATT TOWNE, residing at number 1307 K Street, North West, in
the City of Washington, District of Columbia, United States of America, Chief
Engineer United States Navy, in charge of Bureau of Steam Engineering at
Washington, District of Columbia, United States of America, do hereby declare the
nature of my said invention and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following statement :-
This boiler belongs to the class known as water shell and tube boilers.
Referring to the Drawings:
Figure 1, is a vertical transverse section, about midway of the boiler;
Figure 2, is a side elevation, with part of the outer plating broken away;
Figure 3, is a plan of the boiler with upper casing or uptake removed;
Figure 4, is a front view partly in section and partly in elevation of a modification.
The boiler has an outer water shell, formed by outer plates, A, and inner
plates, A', which form the sides of the water space, B. The top and bottom of the
water space is closed by filling pieces, B1, B1, which are secure. in place by holts or
rivets, or in any other suitable manner. The plates, A, A', may be stayed wherever
it is desirable, by holts or rods, 1, passing through the shell.
The water shell may enclose the fire-box, 2, at the front and rear as well as
the sides, or it may be at the sides only. The grate, 3, is of any approved
construction.
The water shell may be inclined at the sides from the top downwardly and outwardly,
and then inwardly, as clearly shown in Figure 1, so that straight tubes may be used,
and the plates be at about right angles to them, or if the sides of the shell are parallel
the tubes may be bent as in Figure 4, so as to enter the plates, A¹, at about right
angles thereto.
Water tubes, C, C, extend through the combustion chamber from side to side of
the shell, the tubes being inclined for the better circulation of water. The ends of
tubes, C, enter holes in plates, A¹, and are expanded or otherwise secured. The
tubes, (', are in groups, the groups being inclined in opposite directions and alter-
nating, as shown in Figure 1, one group extending from the lower right side to
the upper left side of the boiler, and the next group reversed, as shown in the
drawings.
The outer plates, A, have holes, 5, opposite the ends of tubes, C, large enough
to cut out, expand, or pass said tubes, U, so that the tubes may be removed and
replaced through these holes. There may be a separate opening for each tube,
stopped by a screw plug or openings of sufficient area for a group of tubes or all the
tubes of a section or openings of any desired shape covered by plates, R, removable so
as to afford access to the tube ends.
A steam drum or separator, E, extends lengthwise of the boiler, above the com-
bustion chamber. Tubes D, connect the upper part of the water shell with the sides
of this drum. A return pipe or pipes, G, lead outside the shell from the rear or any
other convenient part of drum, E, to the lower part of the water shell. If a single
pipe is used it is by preference divided into branches, G', G¹, a branch leading to the
lower part of the water shell at each side of the fire-box.
The water will flow down tube, G, by reason of its large size and distance from the
fire, and will flow up in the shell and tubes, C, and so through tubes D, to the drum, E,
hus making complete circulation.
The drum or separator, E, has hoods or deflectors, M, over the ends of the tubes, D,
where said tubes enter the drum. The drum is also divided lengthwise by an upright
artition, N, (which may be perforated). Partition, N, has two curved flanges or

page_text: deflector plates, N¹, N', at its top. The deflector. plates are to prevent priming or
foaming in the drum.
The top of the boiler is covered by plates of shell, L, forming the uptake, and
communicating with stack, K.
The feed water pipe, H, is in the uptake, above tubes, D, and has as many bends as
may be needed, so that feed water is well heated before entering drum or shell, D, at
any convenient point. Steam is drawn from the drum or separator, E, through pipe, F,
which communicates with perforated dry pipe, G³, inside the drum.
For some purposes it is desirable to have the shell with parallel sides and
bent tubes, as in Figure 4; but the straight tubes can be more readily remove!
and replaced.
From the description, the operation of the boiler will be readily understood. The
fire and gases of combustion are in close proximity to the shell, water tubes and
drum. The circulation of the boiler is natural and complete. The water tubes,
entering the side plates at right angles, can be easily removed and replaced.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is―
1. The construction and general arrangement of the water shell and transverse
inclined tubes and the drum substantially as herein described and shown, and for
the purpose set forth.
2. The general arrangement or combination of the water shell and the groups
of inclined tubes, and the covering plates or caps, substantially as herein described
and shown in the drawings.
3. The construction and general arrangement of the water shell and inclined tubes,
and the drum or separator connected to the upper part of the shell and communicating
with the lower part thereof, substantially as herein set forth and shown.
4. The novel arrangement and combination of the water shell and connecting tubes
and the drum or separator having deflecting plates, substantially as hereinbefore
described and shown in the drawings.
5. The general arrangement of the water shell and circulating pipes communicating
with the drum or separator, and the feed water pipe in the uptake communicating with
the separator, substantially as shown and described.
6. The construction and general arrangement of the water shell and connecting
tubes, and the drum or separator covered by the uptake and partly within the com-
bustion chamber, and the tubes leading from the drum, substantially as described and
for the purpose set forth.
Dadth 1 JA *1 1000
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.