Improvements in Tubulous Steam Boilers.
Year: 1896

page_text: Date of Application, 5th Mar., 1896
Complete Specification Left, 5th Dec., 1896-Accepted, 20th Feb., 1897
PROVISIONAL SPECIFICATION.
Improvements in Tubulous Steam Boilers.
1, JAMES WEIR, of Holm Foundry, Cathcart, Glasgow, Engineer, do hereby
declare the nature of this invention to be as follows:-
My invention relates to certain improvements in tubulous steam boilers the
object of same being to render them more efficient particularly when subject to
great variation in the rate of working such as is caused by suddenly starting and
stopping steam engines operated by same.
My invention is applicable to some forms of boilers of the class provided with
two or more lower water drums or shells connected by tubes with an upper water
and steam drum or drums and more particularly to a boiler of the above class
described in an application for Letters Patent of even date herewith in which one
upper and two lower drums are employed together with an arrangement of
connecting tubes whereby those exposed to the greatest heat at their base are led
into the upper drum highest up and those furthest from the fire are led in nearest
the bottom or hottest part of the upper drum in which case those tubes which are
furthest below the water level act as downcast tubes.
According to my present invention I make provision for the free escape of the
steam from the higher or upcast tubes when the steam drum is charged with surplus
water which usually takes place when the engines are started after the boilers
have been filled up or when the engines have been at rest or going slow.
In one form of boiler constructed according to my invention I place an inner
shell in the upper drum which extends up above the water level.
The steam or water rising from the tubes discharges into the space between this
shell and the outer shell, and openings are provided at the top, having deflecting
plates if desired, to direct the steam or water discharged in a downward direction.
The space on the other side of the inner shell which is the larger part of the space
of the upper drum forms a receptacle or reservoir for the surplus water.
At the bottom of the inner shell I provide an opening or openings for the water
to obtain access to the downcast tubes the openings being proportioned to let
sufficient feed return to the boiler. To provide for excessive variation of the
power I may employ adjustable cocks or valves to regulate the return opening or
openings.
In place however of forming the reservoir inside the upper drum I may employ a
separate drum at a higher level and connect it to the former drum (which may
then be made smaller) by a pipe or pipes passage or passages for the steam and
surplus water to get admission. The pipe or passage is led to near the top of the
reservoir. The feed water is returned to the lower drum by pipes or passages and
by preference through a valve or cock for regulating the return feed water.
Or the reservoir drum which may be at a higher or slightly lower level than
the steam drum may be made separate and of sufficient size to work with two or
more boilers to which it would be connected by branch pipes fitted with non return
stop valves on the steam pipes.
The feed return pipes are led from the bottom to the lower water drums.
Dated the 5th day of March 1900
PHILIP M. JUSTICE,
55 & 56 Chancery Lane, London, Chartered Patent Agent,.
For the Applicant.

page_text: Improvements in Tubulous Steam Boilers.
I, JAMES WEIR, of Holm Foundry, Cathcart, Glasgow, 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:-
My invention relates to certain improvements in tubulous steam boilers the
object of same being to render them more efficient particularly when subject to
great variation in the rate of working such as is caused by suddenly starting and
stopping steam engines operated by same.
My invention is applicable to some forms of boilers of the class provided with
two or more lower water drums or shells connected by tubes with an upper water
and steam drum or drums part of the invention being particularly applicable to a
form of boiler in which an upper and two lower drums are employed together with
an arrangement of connecting tubes whereby those exposed to the greatest heat
at their base are led into the upper drum highest up and those furthest from the
fire are led in nearest the bottom or hottest part of the upper drum in which case
those tubes which are furthest below the water level act as downcast tubes.
According to my present invention I make provision for the free escape of the
steam from the higher or upcast tubes when the steam drum is charged with
surplus water which usually takes place when the engines are started after the.
boilers have been filled up or when the engines have been at rest or going slow.
In the accompanying drawings are shown by way of illustration several ways of
carrying my invention into effect.
In these drawings
Figures 1, 2 and 3 are sections at right angles to each other of an upper drum of
a tubulous steam boiler, Figure 2 being a section at the left hand end of Figure 1,
and Figure 3 a section at the right hand end of Figure 1 which itself is divided to
show two modifications.
Figures 4 and 5, and 6 and 7 are sections at right angles to each other respec-
tively of other modifications.
Figure 8 is an end elevation of two boilers showing another modification.
Figures 9 and 10 are sections at right angles to each other showing a modification
as applied to a double ended boiler.
In these drawings the same reference letters and numerals are used to mark the
same or like parts wherever they are repeated.
Figures 1, 2 and 3, show the upper shell A of a tubulous boiler, wherein the
tubes B connecting the lower shells or drums A¹ (not shown in these figures) are
so arranged that those tubes exposed to the greatest heat are led into the upper
shell or drum A highest up, and those furthest from the fire are led in nearest the
bottom portion of the shell A, and where those tubes furthest below the water
level act as downcast tubes, and where consequently no separate downcomers will
be required. For the purpose of iny invention the inner shell M is placed in the
upper drum A and extends up above the water level. The steam or water rising
from the tubes B discharge into the space between this shell M and the outer shell
which forms a part of the boiler proper. Openings N, are provided at the top
having deflecting plates N' if desired. In the right hand side of Fig. 1 and in
Fig. 3 the arrangement of the shell M and deflecting plates N¹ differs from that
at the opposite end of Fig. 1 and in Fig. 2. The space H ou the other side of the
inner shell M forms a receptacle or reservoir for the surplus water. At or neat
the bottom of the reservoir H and communicating with the space between the
shell M and the outer shell I provide an opening K proportioned to allow sufficient
feed to return to the boiler, and to provide for variations in the power, 1 employ

page_text: an adjustable cock or valve K' to regulate the return of sufficient feed to the
boiler. Alternatively or conjointly there may be provided in the space H a feed
return pipe I with an adjustable cock K' connected with the lower drum. G' is
the steam collecting pipe communicating with the outlet G to which the main
steam pipe is applied."
Figures 4 and 5 show an upper drum of a tubulous boiler in which the tubes B
may be arranged and connected to the lower water drum in any manner, on account
of its being fitted with the ordinary downcomer C. The reservoir H is formed in
one end of the upper drum A by the division plate M. The feed supply from the
reservoir H to the boiler obtains access thereto either by the valve K¹, or by the
feed return pipe 1 and valve K. G is the steam outlet.
In the modification shown in Figs. 6 and 7, instead of forming the reservoir
inside the drum, a separate drum H is employed on a higher level, and is connected
to the drum A by a pipe L led to near the top of the reservoir H. The water is
returned to the lower drum A, by the pipe I provided with the adjustable cock or
valve K which pipe I is led to near the bottom of the drum A. B are the water
tubes and C is an ordinary downeomer to the lower drum.
In Figure 8, the reservoir H is made separate, and is connected to two
boilers AA by the pipes L L, fitted with the non return valves L¹ L'. The
feed return pipe I is led from the bottom of the reservoir H to the lower
drums AA and adjustable cocks or valves K K are placed therein to regulate
the quantity of feed water returned. The ordinary check valves E may be fitted
as usual to the upper or lower drum or to the reservoir H. CC are ordinary
downcomers.
Figures 9 and 10 show a sectional end and side elevation of part of an upper
drum, and also a side elevation of a part of a lower drum of a tubulous boiler, to
a slightly larger scale, to indicate more particularly the position in which the
gauge cocks, feed check valves, and other mountings may be placed, and to
show more clearly the difference between the present invention, and previous
arrangements which it may appear to resemble.
It is not now, but was formerly a common practice to fit separate steam chests to
boilers, connected thereto by admission and return pipes with and without cocks
and valves, and these in some cases resemble in appearance and connections some
modifications of the present invention; but both in purpose and in action these
arrangements differ essentially from the present invention. The purpose of the
steam chest was to augment the capacity of the boiler, and of the return pipe to
remove any water collecting through condensation or priming.
It is also a common practice to fit vessels for separating any water carried over
by the steam, the water collected in them being disposed of in various ways,
such as by being returned direct to the boilers, or by being blown into the
feed tanks.
The distinction between the present invention and apparatus as described above,
and known as steam chests or separators, is that by this invention the water carried
into the vessel or reservoir is retained in it, and only allowed to return at the rate
required to supply the necessary feed, thereby relieving the boiler proper of the
surplus water, which, however, is still available for evaporation, whereas in the
old apparatus resembling in any modification this invention, the boiler proper is
not relieved of the surplus water, unless by the removal thereof, in which case it
is not available for evaporation.
In Figures 9 and 10, the reservoir H is arranged at the middle of the top drum
between the division plates M M, the space A A between these plates and the end
of the shell being parts of the boiler proper. The pipe I, and the valve K', are
for the feed return from the receiver H to the lower drum A', and C C are the
ordinary downcomers connecting the upper drum and the lower drums A' A'.
The usual boiler mountings, such as the feed check valve E E may either be
placed on the upper or lower drums, or on the reservoir H. The water gauge F
is fitted as usual on the drum A, and a gauge must also be titted to the reservoir H

page_text: as shown at F1, as the water level will generally be at a different height in A and
in H when the boiler is working. The relative heights will depend on the rate of
evaporation. The levels will be the same in the reservoir H and in the portions of
the boiler proper A when the boiler is at rest. The steam outlet G should be
placed over the reservoir H. Deflecting plates or collecting pipes may be fitted
as usual in the case of tubulous boilers.
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. A tubulous boiler having a reservoir formed or fitted therein to receive and
connections to retain and regulate the return of the surplus water at the rate
required for feeding substantially in the manner and for the purposes hereinbefore
.described.
2. In combination with a tubulous boiler a separate reservoir to receive and
connections to retain and regulate the return of the surplus water at the rate
required for feeding substantially in the manner and for the purposes hereinbefore
described.
3. The combination with two or more tubulous boilers of a reservoir to receive
and connections to retain and regulate the return of the surplus water at the rate
required for feeding substantially in the manner, and for the purposes herein before
described.
4. The various arrangements and constructions of tubulous boilers substantially
as described and illustrated in the drawings.
Dated this 4th day of December 1896.
PHILIP M. JUSTICE,
55 & 56 Chancery Lane, London, W.C., Chartered Patent Agent,
For the Applicant.