Improvements in Steam Boilers.
Year: 1891

page_text: Date of Application, 17th Feb., 1891
Complete Specification Left, 17th Nov., 1891-Accepted, 24th Dec., 1891
PROVISIONAL SPECIFICATION.
Improvements in Steam Boilers.
I, CHARLES EDWIN MARSTON of Richmond Street, Dover, New Hampshire,
United States of America, Founder and Machinist, do hereby declare the nature
of this invention to he as follows:-
My invention relates to an improved steam boiler in which the combustion
chamber is formed by a series of vertical tubes cach connected with the water
supply and steam dome and provided with a branch pipe extending from the said
tube and opening into it near the top and bottom. The boiler has a hollow ring-
shaped base connected with the water supply pipe within which may be arranged
the fire pot for heating the boiler. From the top of the base there extends upwards
a series of pipes connected with vertical tubes set in a circle and having their
outer sides curved so that the several tubes form a wall or shell for a combustion
chamber, an opening being left between the tubes at one point to provide for a
feed door. The tubes may be arranged in other forms. The inwardly-extending
sides of each tube are inclined towards each other so that the sides of the several
tubes do not touch. Each tube at its upper end is provided with a pipe which
opens into and supports a steam dome having a dished bottom and an inverted
dished top from which leads the steam pipe for carrying off the steam. The pipes
extend into the steam dome to about the horizontal plane, passing through the
joint of the bottom and top, so that water can collect in the dished bottom and
remain there to protect it from the heat of the fire box. Each of the vertical
water tubes is provided with a branch which extends from near the bottom of the
tube inwards and curves back again to enter the tube at or near its top above the
water line. This branch is preferably of wrought iron, its ends being cast into
the side of the tube and it is also provided with series of outside annular flanges.
Annular flanges are also formed on the inner sides of the tube. To the centre of
the bottom of the steam deme is secured a short pipe, the upper end of which is in
line with the upper ends of the pipes which support the dome while the lower end
connects with a downwardly extending pipe opening into a chamber from which
extends downwards a series of flanged pipes opening into a second chamber
connected with the feed water pipe.
The operation is as follows;--The water fills the base and partially fills the
tubes and their branch pipes. The water also fills the central chamber and pipes
to the same level. Now, when heat is generated in the base, the water in the
several parts is rapidly heated and the steam generated passes through the pipes to
the steam dome and is taken from the latter by the steam pipe. The water of con-
densation in the steam dome accumulates in the dished bottom so that the latter is
constantly covered with water which protects it from the heat of the fire-box, and
surplus water in the said steam dome passes through the pipes into the tubes and
through the central pipe and chamber to the pipes connecting the two chambers.
By having water in the steam dome and in the tubes, two water levels are formed
one above the other with a dry or superheating space between the two levels.
The heat passing up in the centre of the boiler, heats the branch pipes to a higher
degree than the tubes so that the water in the said branch pipes boils up through
their upper ends and passes into the tops of the tubes and a complete circulation
of the water takes place in each of the tubes. The water in boiling over the upper
end of the branch pipes into the upper ends of the tubes, readily separates from
the steam which latter passes up to the dome while the water by its own weight
falls down the tubes until it strikes the water therein. The steam in passing up to
the dome is partly superheated so that the steam in the dome is in a very dry state.

page_text: By reason of the branch pipes projecting into the interior space or combustion
chamber formed by the tubes, a large heating surface is obtained which, in con-
nection with the large heating surface of the central pipes and chambers as well
as of the tubes, permits of generating steam very quickly.
Dated this 17th day of February 1801
CHARLES EDWIN MARSTON.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Steam Boilers.
I, CHARLES EDWIN MARSTON of Richmond Street, Dover, New Hampshire,
United States of America, Founder and Machinist, 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 object of the invention is to provide a new and improved boiler which is
simple and durable in construction, takes up very little room, presents a great
heating surface, and permits of generating steam very rapidly.
The invention consists of a series of tubes each connected with the water-supply
and steam-dome and provided with a branch pipe extending from the said tube
and opening into it near the top and bottom.
The invention also consists in certain parts and details and combinations of the
same as will be described hereinafter and then pointed out in the claims.
Reference is to be had to the accompanying drawings, forming part of this
Specification, in which
Figure 1 is a sectional side elevation of the improvenient, on line 1-1
Figure 2:
Figure 2 is a sectional plan view of the same on line 2-2 Figure 1; and
Figure 3 is a side elevation of one of the tubes.
Similar letters of reference indicate corresponding parts in all the figures.
The improved boiler A is provided with a hollow ring-shaped base B connected
with the water-supply pipe C for filling the boiler with water. Inside of the ring-
shaped base B may be arranged the fire-box for heating the boiler in the usual
manner. From the top of the base B extends upwards a series of pipes D con-
nected with vertically-arranged tubes E set in a circle and having their outer sides
curved so that the several tubes form a wall or shell for a combustion-chamber.
One or two tubes E are left out to form an opening for a fire-door. The tubes
may also be arranged in other forms than a circle. The inwardly extending sides
of each tube are inclined towards cach other, as is plainly shewn in Figure 2, so
that the sides of the several tubes do not touch and the heat is permitted to readily
pass on to the said sides. From the upper end of each tube E extends a tube F
opening into and supporting the steam dome G having a dished bottom G¹ and an
inverted dished top G2 from which leads the steam pipe H for carrying off the
steam. The pipes F extend into the steam-dome G to about the horizontal plane,
passing through the joint of the bottom and top G and G2 respectively so that
water can collect in the dished bottom G' and remain there to protect said bottom
from the heat of the fire-box. Each of the tubes E is provided with a branch
pipe I which extends from near the bottom of the tube inward and curves back
again to enter the tube at or near its top above the water-line, as is plainly shewn
in Figure 1. This branch pipe is preferably of wrought-iron, its ends being cast
into the side of the tube E and it is also provided with series of outside annular
flanges, as is plainly shewn in Figure 3. Annular flanges are also formed on the
inner sides of the tube E. In the centre of the bottom G¹ of the steam-dome G
is secured a short pipe J the upper end of which is in line with the upper ends of

page_text: the pipes F while the lower end connects with the downwardly-extending pipe K
opening into a chamber L from which extends downwards a series of pipes N
opening into a second chamber O connected by a pipe P with the feed pipe C.
The pipes N are also provided with annular flanges.
The operation is as follows-The water passing through the supply-pipe C fills
the base B the pipes D and extends into the tubes E and the branch pipes I to
about the height shewn in Figure 1. The water also passes from the feed-pipe C
to the pipe P to the chamber O and extends in the pipes N to the same level as in
the tubes E and the pipes I. Now, when heat is generated in the base B the
water in the several parts is rapidly heated and steam is generated which steam
passes through the pipes F, K, and J, to the steam dome G and is taken from the
latter by the pipe H to the apparatus or machine for utilizing its power. The
water of condensation in the steam-dome G accumulates in the dished bottom G¹
so that the latter is constantly covered with water which protects the said bottom
from the heat of the fire and surplus water in the said steam-dome can pass readily
through the pipes F into the tubes E and through the centre pipe J through the.
pipe K and the chamber L to the pipes N. By having water in the steam-dome G
and in the tubes E two water levels are formed one above the other with a dry or
superheating space between the two levels. The heat passing up in the centre of
the boiler heats the branch pipes I to a higher degree than the tubes E so that the
water in the said branch pipes I boils up through their upper ends and passes into
the tops of the tubes E so that a complete circulation of the water takes place in
each of the tubes by means of the branch pipe I. .It will be seen that the water
in boiling over the upper end of the branch pipes I into the upper ends of the
tubes E readily separates from the steam which latter passes up to the dome G by
the pipe F while the water by its own weight falls down the tubes E until it strikes
the water therein. It will further be seen that the steam in passing up to the dome G
is partly superheated in the pipes F the compartment Land the pipe K so that the
steam in the dome G is in a very dry state. It will further be seen that the branch
pipes I project into the interior space or combustion chamber formed by the series
of tubes E and thus a large heating surface is obtained which, in connection with
the large heating surface of the pipes N the chambers O and L as well as of the
tubes E, permits of generating steam very quickly.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what
I claim is―
1. In a steam boiler, the combination, with a dome having a dish-shaped bottom
and a hollow base, of a series of vertical tubes arranged to form a combustion
chamber with three sides of each tube presented to the combustion chamber and
tubes provided with inwardly-curved branch pipes the top end of said pipes to
discharge back into the vertical tubes above the water-line in said tubes and short
pipes connecting the tubes with the dome projecting into the dome and above the
bottom thereof, substantially as shewn and described.
2. In a boiler, the combination, with a dome having a dish-shaped bottom, of a
chamber below the dome a pipe connecting the chamber and dome said pipe
projecting into the dome above the bottom thereof a second chamber below the
first-named chamber and communicating with the water-supply and vertical pipes
connecting the two chambers, substantially as described.
3. In a boiler, the combination of a dome having a dish-shaped bottom, a ring-
shaped base, vertical tubes communicating with the base and dome and provided
with inwardly-curved branch pipes, a chamber below the dome and communicating
therewith, a second chamber communicating with the water supply, and vertical
tubes connecting the two chambers, substantially as herein shewn and described.
4. In a steam boiler, the combination of a dome having a dish-shaped bottom,
vertical tubes provided with curved branch pipes and arranged to form a combus-
tion chamber, a series of pipes leading from the tubes into the dome with their

page_text: ends projecting above the bottom thereof, a chamber below the dome and provided
with an upwardly extending pipe, a short pipe secured to the centre of the bottom
of the steam-dome and in communication with the pipe of the said chamber, a
second chamber below the first named chamber and pipes connecting the two
chambers, the vertical tubes and the lower chamber being connected with the water-
supply, substantially as described.
5. A steam boiler having two water levels one above the other and a dry or
superheating surface between the two water levels, substantially as shewn and
described.
11 1001
C. E. MARSTON.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.