Improvements in Steam Boilers.
Year: 1894

page_text: Date of Application. 18th Oct., 1894-Accepted, 24th Nov., 1894
COMPLETE SPECIFICATION.
Improvements in Steam Boilers.
We, HENRY TETLOW, Manufacturer, of Allen's Lane, Mount Airy, and
THOMAS HARRISON, Machinist, of 2439 North 18th Street, both of the City and
County of Philadelphia, State of Pennsylvania, United States of America, 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 improvement contemplates certain features of construction which permit
more perfect circulation of water and steam in a boiler entirely built up of tubes.
The invention also includes specific improvements in the construction looking to
the assembling of the parts making up the water circulatory system in such a way
that a water tube may be readily replaced when defective and without dismantling
the structure as an entirety.
In carrying out our invention we employ large upright tubes located at each
corner, and these are connected at the sides and back by a large horizontal tube at
the bottom of the boiler; and at front, sides, and back by horizontal tubes at the
A
top of the boiler. There is also a large transverse or cross tube connecting the
two front upright corner tubes located intermediate of the top and bottom.
series of steam generating tubes of small diameter have their tops connected with
the upper side horizontal tubes and their bottoms with the horizontal bottom side
tubes. In addition to these two sets of steam generating tubes there are two
other sets of similar tubes connected at the bottom with the two large transverse
tubes and at the top with the upper large transverse tubes. These generating
tubes have horizontal, or approximately horizontal, portions or sections. These
various generating tubes are coupled in position and connected with branches
from the main large tubes by detachable couplings, preferably of the construction
shown, so that any complete generating tube may be readily removed, repaired
The fire grate is arranged between the
and replaced, or replaced by a new one.
walls of vertical tubes and below the intermediate frout transverse tube and also
below the horizontal parts of the generating tubes. The steam drums are formed
of two rearwardly extending large tubes supported by and connecting with the
four upright or corner tubes, two of which open into the bottom of one steam
drum and two into the bottom of the other steam drum. The drums are also
connected together at each end by transverse tubes or pipes, from one or both of
which steam may be led to the place of consumption. In one of said connecting
The entire structure is enclosed by brick-
pipes the safety valve may be placed.
work on sides and back and by britching in front, and long doors or removable
plates are arranged therein adjacent to or over the couplings in the generating
tubes to permit access thereto when it may be necessary to make repairs or replace
a defective tube. In the operation of our improved boiler the heat from the
O furnace grate is caused to come into contact with the horizontal portions of the
small generating tubes, thus generating steam very quickly and utilizing to the best
advantage the products of combustion. The water is kept in a constant circulation
and permits the ready escape of steam from the various pipes to the steam drums
when it is clearly separated from any ebullition of the water, and thus may be
5 delivered to the engine in a comparatively dry state. This is very advantageous
in that it permits a greater evaporation duty per pound of coal than in those cases
where the hot water of the boiler is carried off in suspension with the steam.

page_text: Our invention will be better understood by reference to the accompanying
drawings, in which :
Fig. 1 is a front elevation of our improved boiler;
Fig. 2 is a longitudinal vertical sectional view on the line - of Fig. 1;
Fig. 3 is a vertical sectional detail view on an enlarged scale of one form of
coupling which may be employed;
'
Fig. 4 is a similar view of one of the couplings for the small horizontal pipes;
Fig. 5 is a side elevation of the structure with its enclosing walls; and
Fig. 6 is a perspective view of the boiler structure composed of the large pipes.
A are the large vertical pipes. The bottoms of the pipes A, A, on each side are
connected by large side pipes B. C is a large transverse pipe connecting the two
rear pipes A, A. The tops of the pipes A, A on each side are connected by the
large side pipes D. E is the rear transverse pipe connecting the tops of the two
opposite rear pipes A, A.
Fis the front transverse pipe connecting the tops of the two opposite front
pipes A, A. G is the intermediate large transverse pipe connecting the two
opposite front pipes A, A between their tops and bottoms. All of these pipes
described are united at their points of connection by suitable water and steam
tight couplings.
H, H are the steam drums which are connected with the tops of the pipes A, A
through the connecting pipes or couplings h, h, the pipes A, A on one side being
connected with one drum H and the pipes A, A on the other side with the other
drum. The drums H, H are connected together at each end by transverse tubes
or pipes i, i, from one or both of which steam may be led to the place of con-
sumption. The two transverse connecting pipes i, i may be connected by a pipe or
tube. In one of these connecting pipes i a safety valve may
be placed.
I are a set of small tubes connecting one of the lower side pipes
with one of
the upper side pipes D and having horizontal portions I¹ extending from side to
side within the structure composed of the large pipes.
J are a similar set of small tubes connecting the other lower side pipe B with
the other upper side pipe D and having similar horizontal portions J' extending
from side to side within the structure composed of the large pipes.
K are a series of small tubes connecting the lower transverse rear pipe C with
one of the transverse upper pipes and having horizontal portions Kextending
longitudinally within the structure composed of the large pipes and preferably
above the horizontal portions I' and J' of the pipes or tubes I and J.
L are another set of small pipes or tubes connecting the intermediate transverse
pipe G with the other upper transverse pipe and having horizontal portions L'
similar to the horizontal portions K¹ of the pipes or tubes K.
I prefer to connect the small pipes or tubes I, J, K and L, with the opposite top
and bottom pipes, and they are so shown in the drawings. Thus the pipes or tubes
I and J respectively connect one of the bottom side pipes B with the opposite top
side pipes D; and the pipes K and L respectively connect the lower pipes C and Ġ
with the upper transverse pipes F and E. It will be understood however, that
these small pipes or tubes I, J, K and L, may connect the upper and lower pipes
on the same side, instead of the opposite pipes.
The various small pipes I, J, K and L, may be connected with the respective
large pipes B, C, D, E, F and G, by suitable couplings. The connection is
preferably made through coupling M uniting the ends of the pipes I, J, K and L,
with short pipe sections b, c, d, e, f, and g, and carried by the respective pipes B, C,
D, E, F, and G. By the use of such couplings the pipes I, J, K and L, or any
portion of them, may be easily disconnected without dismantling the entire boiler.
To permit easy access to these couplings M, the enclosing structure T may be
provided with doors t suitably located to permit the couplings to be reached from
the outside when the doors are opened.
In Fig. 3 we have shown a form of coupling which may be employed. In this
construction the coupling M consists of the two parts N and O adapted to be secured

page_text: together as by a bolt P. The parts N and O are provided respectively with
threaded necks n and o adapted to receive the threaded ends of the pipes J &c.
and b &c. Any other form of coupling may however be employed.
In Fig. 4 is shown our preferred coupling for the horizontal portions of the
pipes I, J, K and L. This consists of a hollow cap Q provided with threaded
to receive the ends of two horizontal portions, I, J, K, L¹.
sockets
R is a removable plug in the cap Q in line with one of the sockets 9 so that when
the plug is removed a cleaning rod may be inserted through the cap directly into
one of the pipes connected therewith. Thus each cap gives access to the interior
of one of the two pipes coupled by it and in that manner each horizontal pipe
may be cleaned.
.
While the sections I, J, K¹ and L', are described as horizontal pipes, it will be
observed that they incline slightly from the horizontal plane.
S is a water pipe which supplies water to the lower portion of the pipe structure
formed by the large pipes. The grate is located within the structure below the
horizontal pipes I, J, K' and L, as shown at U in dotted lines in Fig. 2 so that
these horizontal portions of small pipe are subjected directly to the heat.
While we prefer the minor details of construction shown we do not limit ourselves
to them as they may be varied without departing from the invention.
The pipe structure which composes the boiler will be enclosed in a suitable
setting of brick as has been heretofore stated or when used as a marine or
locomotive boiler it may be enveloped in a suitable metal structure.
To increase the height of the boiler, when the same is desired it is apparent that
a second pipe section or structure composed of the large upright corner pipes,
upper horizontal connecting pipes and small tubes may be coupled with the upper
large horizontal pipes of the first section or structure.
The operation of the boiler in the generation of steam will be readily understood
from the foregoing description of the construction of the boiler. The water is
admitted to the structure of large pipes by the pipe S and is subjected to the
products of combustion from the grate U. The connecting pipes or tubes induce
a constant circulation of the water so that it is thoroughly subjected to the heat,
giving off its steam which passes off through the connecting tubes into the steam
drums H. As these drums are connected with the upright pipe A, A the steam
will be separated from the water of ebullition the steam passing up through the
connecting pipes and the water filling through the tubes A. Thus a more dry
steam is produced.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. The tubular steam boiler provided with a steam drum or drums having steam
inlet passages leading directly from above the vertical return tubes A.
2. A tubular steam boiler composed of upper and lower large horizontal tubes
connected by small generating tubes having more or less horizontal portions, the
lower large horizontal tubes being below the grate.
3. A tubular steam boiler with the parts arranged and constructed substantially
as described.
Dated this 16th day of October 1894.
HENRY TETLOW.
THOMAS HARRISON.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicants.