Improvements in and relating to Steam Boilers.
Year: 1895

page_text: Date of Application, 2nd Apr., 1895-Accepted, 4th May, 1895
Improvements in and relating to Steam Boilers.
We, PATRICK MEEHAN, and JOHN JOSEPH MEEHAN citizens of the United
States of America, both of No. 8 Bluff Street, in the Town of New Castle, County
of Lawrence and State of Pennsylvania, one of the United States of America,
Boiler Builders, 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 :-
Figure 1 is a longitudinal central section of our improved steam boiler, some of
the parts being shown in full lines ;
Figure 2 is a vertical cross-section on the line 2-2 Figure 1;
Figure 3 is a detail cross-section on the line 3-3 Figure 1 i and
Figure 4 is a longitudinal section of a portion of a corner and side, showing the
arrangement of the circulation tubes.
Our invention relates to steam boilers, and more particularly to that class of
boilers known as smoke-flue boilers.
The object of our invention is to provide a smoke-flue boiler in which the
constant circulation of the water is obtained, and also one in which we provide
safety tubes which will burn out when the water in the boiler gets below a certain
level, and thus prevent the explosion of the boiler.
To these ends our invention consists, generally stated, in a furnace having a
smoke-flue boiler arranged therein, a drum within said furnace, a series of ascending
water tubes connecting said boiler and drum, said tubes being directly in the path
of the products of combustion, and a series of safety tubes leading from the rear
end of said drum upwardly and adapted to enter the rear head of said boiler at the
water-line, just above said smoke-flues, and a wall interposed between said safety-
tubes and the products of combustiou; said safety-tubes, however, being directly
exposed to the action of the products of combustion where they enter said boiler,
whereby when the water in the boiler falls below the water-line the upper ends of
said safety-tubes being exposed to the products of combustion will burn out and
prevent the explosion of said boiler. Our invention further consists in certain
other details of construction and combination of parts, all of which will be fully
hereinafter set forth.
Like letters indicate like parts in each of the figures of drawing.
As illustrated in the drawings, the furnace a is provided, having the fire-
chamber 6 located at its forward eud, said fire chamber having the coaling door b',
grate bars 3, ash pit c, and the ash pit door c'. Supported on the walls a' of the
furnace a is the smoke-flue boiler d having the smoke flues d' therein, said smoke-
flues communicating with the stack or chimney (not shown). The boiler d is also
provided with the ordinary safety-valve and man-holes d³. Below the boiler d
in the furnace a is the drum e, which is connected with said boiler d by the
water-tubes f. A man-hole el is provided at the rear end of said drum. A
water supply pipe 9 enters the top of the boiler d and communicates with the
reservoir g, which is supported in suitable brackets g' in the top of said
boiler. The upper portion of the reservoir g¹ is provided with the openings g³
which allow for the entrance of steam from the boiler d. The steam thus
admitted acts to boil out the sediment from the water within said reservoir, so
that when the water passes to the drum below the sediment will be immediately
deposited at the bottom thereof. Leading from the said reservoir g' are the auxiliary

page_text: pipes which pass down through two tubes f1 f of the water tubes f and
enter the drum e, whereby the water is fed to said drum. By having the
auxiliary pipes 9 extending down into the drum, and dirt or sediment carried
into said drum by said pipes will collect at the bottom of said drum while at
the same time the water passing, through said pipes g* will not be converted
into steam before it reaches said drum. The ends of the auxiliary pipes g' are
bent at an angle to the main body thereof, as at g' so that the water passing
down through said tubes will not fall with such force as to stir up the sediment
within said drum. Furthermore, by having the auxiliary pipes enclosed by the
tubes ff and subject to high heat, the water in passing through said auxiliary
pipes will be raised to the degree of heat of the boiler, so that when the
water arrives at the drum e much of the sediment will have been boiled out,
and will drop immediately to the bottom of said drum, thus leaving the water
which is to pass back through said tubes finto the boiler, practically clear and free
from sediment.
In the rear of the furnace a are the safety-tubes h which connect the rear boiler
head d with the drum e, said safety tubes h pass up on the outside of the rear
wall a² of the furnace, being arranged within recesses a³ in said wall. The upper
ends of said safety-tubes are provided with the connections which connect said
safety-tubes with the sections which enter the boiler at 3. The wall a² does
not protect these sections of said safety tubes, but they are left exposed to
the heated products of combustion within the furnace walls. The wall a² keeps
the safety-tubes hat a lower temperature than the water-tubes f, so that the water
passes up from the drum e into the boiler and down from the boiler into the drum
through the safety-tubes h, whereby a constant circulation is maintained. The
important function, however, of the tubes is to allow for the escape of steam
when the water in the boiler gets below the water-line. By the water-line we
mean the lowest point to which the water can go with safety. For this reason,
the safety-tubes h enter the boiler at the water-line. When the water in the boiler
falls below the water-line, there will not be any water in the sections of the
safety-tubes where they enter said boiler, and as they are exposed to the direct
action of the heated products of combustion, the said sections will be burned out.
This will permit of the escape of the steam in the boiler, and so prevent the
explosion of the same.
Connected to the drum e are the tubes i which pass up on the outside of the
walls a' of the furnace a and enter the boiler d at or about the water-line, said
tubes being arranged within recesses in said walls. As these tubes i perform
the function of circulating tubes, they must be kept at a lower temperature than
the water-tubes f, and for this reason they are protected from the direct action of the
beat by passing up outside of said wall a¹. They may be protected against the
action of the heat in other ways, and we do not confine ourselves to the particular
way shown, in which they are carried up outside of the walls of the furnace.
These tubes being at or near the water-line, perform the further function of
carrying off any dirt or sediment which may collect on the surface of the water
within the boiler. In order to blow out the sediment which collects in the
drum e we provide the pipe k connected to the drum by the T's k¹. The pipe k is
provided with the valve l.
The operation of our improved boiler is as follows:
The fire being started in the fire chamber b of the furnace a, the products of
combustion will come in contact with the water tubes f, and, passing through the
openings between said tubes, will reach the rear end of the furnace, whence they
will rise directly to the smoke flues d' of the boiler d, thence out the front end
of the stack or chimney. The water-tubes f, being in the direct path of the
products of combustion, are raised to a high heat, but the safety-tubes h being
protected by the wall a' are not subjected directly to the heated products which,
when they reach the rear of the furnace, are drawn immediately upward by
the draught of the chimney connected with the smoke-flue. The sections

page_text: however, of said safety-tubes h, where said tubes enter the boiler d, are subjected
to a high heat by the products of combustion as they rise to enter the smoke
tubes d. Meanwhile, water is fed to the water reservoir g' through the supply pipe g
in the top of the boiler. The openings g³ in the reservoir gi admit steam from
the boiler, which acts to raise the water contained within said reservoir
to a high heat, whereby much of the sediment of the water is boiled out
before passes down the auxiliary tubes y. In this way, when the water passes
down into the drum e, the sediment having been largely boiled out in the reservoir,
will be deposited at the bottom of the drum, so that the water passing up the
tubes will be practically free from sediment. As the water-tubes have been
heated by the products of combustion, the water from the drum e will pass up
through said water-tubes into the boiler until it arrives at the proper height
therein, which is regulated by means of the ordinary water-column and gauge-cock.
The generation of the steam, of course, takes place in the boiler d, but as the water
keeps entering said boiler through the water-tubes f, and the tubes h and i are cooler
than the water-tubes f, the water passes downward through said tubes and i into
the drum e whence it again ascends through the water-tubes f, and thus a constant
circulation is obtained. In case the water in the boiler d falls below the prescribed
water level, the action of the heat upon the sections h³ of the safety-tubes h at the
point where they enter said boiler will burn out said safety-tubes at that point and
give vent for relieving the pressure from the boiler, and thus prevent the explosion
of the same.
When it is desired to clean out the drum e the valve in the pipe k is opened.
The pressure within the drum will force out all the sediment and filth contained
therein. By having the two or more exits from the drum, all parts of said drum
are thoroughly cleansed, and none of the sediment remains in the ends thereof, as
is the case in blow-offs having only one exit from the drum.
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 combination with a furnace having a fire chamber therein, of a boiler
having smoke-flues, a drum, a series of tubes connecting said boiler and drum
and exposed to the heated products of combustion, and safety-tubes leading from
the rear end of said drum upwardly and constructed so as to enter the rear head of
said boiler at the water-line just above the said smoke-flues, and a wall interposed
between said tubes and the heated products of combustion on their way to said
smoke-flues, said safety-tubes being exposed where they enter said boiler, whereby
said safety-tubes will be directly acted upon by the heated products entering said
smoke-flues, substantially as and for the purposes set forth.
2. The combination with a furnace having a fire chamber therein, of a boiler, a
drum beneath said boiler, a series of ascending water-tubes connecting said boiler
and drum, safety-tubes connecting said drum and the rear of the boiler at or about
the water-line, a series of descending water tubes connecting said drum and the sides
of the boiler at or about the water line, and water-feed pipes for supplying the
water from the feed water heater to said drum, substantially as and for the purposes
set forth.
3. The combination with a furnace, of a boiler, a drum beneath said boiler, a
series of water-tubes connecting said boiler and said drum, and water-feed pipes
passing down through said water-tubes into said drum, said feed pipes having the
lower ends thereof turned at an angle to the inain body, substantially as and for the
purposes set forth.
4. The combination with a furnace, of a boiler, a drum beneath said boiler, a
water reservoir suspended within the steam space of said boiler, and pipes leading
therefrom. to said drum, substantially as and for the purposes set forth.
5. The combination with a furnace, of a boiler, a drum beneath said boiler, a
water reservoir within the steam space of said boiler having openings in the top

page_text: thereof, and pipes leading therefrom to said drum, substantially as and for the
purposes set forth.
6. The combination with a furnace, of a boiler, a drum beneath said boiler, a
series of water tubes connecting said boiler and said drum, and a blow-off pipe
outside of said drum, arranged longitudinally of said drum and connected thereto,
said drum having two or more exits leading to said pipe, substantially as set forth.
Dated this 2nd day of April 1895.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.