Novel or Improved Apparatus for use in Maintaining the Water in a Steam Boiler, or in each of a Number of Steam Boilers, at, or Approximately at, a Constant or Desired Level.
Year: 1897

page_text: Date of Application, 24th Dec., 1897
Complete Specification Left, 26th Sept., 1898-Accepted, 19th Nov., 1898
Novel or Improved Apparatus for use in Maintaining the Water in a
Steam Boiler, or in each of a Number of Steam Boilers, at, or
Approximately at, a Constant or Desired Level.
We, JOSEPH EVANS and WILLIAM EVANS, trading together in co-partnership as
Joseph Evans and Sons, of Culwell Works, Heath, Town, near Wolverhampton,
in the County of Stafford, Hydraulic Engineers, and ABRAHAM HOPWOOD, of
3, Culwell Terrace, Cannock Road, Wolverhampton aforesaid, Engineer, do hereby
declare the nature of this invention to be as follows:
Apparatus forming the subject matter of this invention is devised, more
especially, for use with watertube boilers, in which the water level is liable to
considerable fluctuation; but the apparatus may be used, also, with advantage,
with steam boilers generally.
essential
Apparatus constructed according to this invention, comprises, as
features, a feed pump or injector, which may be of any ordinary or convenient
66
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description, and a pump, hereinafter termed the return pump, of which the
suction pipe or passage communicates with the interior of the boiler at the
normal or desired level of the water therein, and of which the discharge pipe or
passage communicates with a receptacle from which water is drawn into the
feed pump or injector or communicates directly with the suction pipe or passage
of the feed pump or injector. The function of the return pump is to withdraw
from the boiler any water which rises above the normal level therein, and deliver
it either into the receptacle, aforesaid, or directly into the suction pipe or passage
of the feed pump or injector. When the water in the boiler is at its normal
level, the suction pipe or passage of the return pump is open only to the steam
space of the boiler, and steam only passes through the pump. The steam thus
delivered by the return pump either heats the water in the receptacle, aforesaid,
or heats the water in the suction pipe or passage of the feed pump or injector.
In order to prevent the water or steam from the boiler being discharged in a con-
tinuous stream through the return pump valves, irrespective of the working of
the pump, the discharge valve, or each discharge valve, is pressed down by a
piston the back of which is exposed to the steam pressure of the boiler, or by a
spring or weight, or by a weighted lever, so that it cannot be opened until the
pressure of the steam or water within the pump is raised, by the action of the
pump, above the boiler pressure.
For the purpose of preventing the entrance of scum from the boiler into the
return pump, the open end of the suction pipe of such pump may be conveniently
formed of a T-shape, of which the head of the T is vertical and the ends thereof
open. The head should, of course, extend for the purpose sufficiently above and
below the portion of the pipe which joins thereinto to insure that, under all
circumstances likely to occur in working, the water level will always be between
the upper and lower ends of the head." In lieu of forming the pipe with a
T-head, the open end of the pipe may communicate with a space which is sur-

page_text: rounded by a shield or is enclosed between the end or side of the boiler and a
shield, and in such case the end of the pipe may be formed as a bend, and the
portion of the pipe which passes through the end or side of the boiler be adapted
to be turned axially so that by turning such portion the level of the open end of
the pipe may be varied.
The improved apparatus may be used, also, to assist the circulation of the water,
more especially in the case of a water tube boiler; and such purpose will be best
effected by introducing the feed water into the lower portion of the boiler.
When a feed pump is employed with the return pump, both the pumps may be
operated by the same mechanism, or by mechanism operated from a common
motor; for instance, they may be connected together and be operated by a
single crank or eccentric, or by a single steam cylinder, or they may be each operated
by a separate crank or eccentric which are both operated by the same shaft. The
feed and return pumps may be of equal or unequal capacity; and in the case of
either, or both, of them, suitable provision may be made for varying the stroke
or speed. Either, or both, of these pumps, also, may be either single or double
acting.
A single pump may be adapted to act both as the feed and return pump, by
providing it with a piston and utilizing one end of the pump for the one purpose
and the other end for the other purpose.
When two separate pumps are used, and both are single-acting, it is preferred
that the one pump shall be discharging while the other is filling, and vice versa,
as in such case the power required to cause the discharge of the feed pump is
furnished, or largely so, by the pressure of the water or steam which issues from
the boiler into the return pump during the suction stroke of such pump.
I have described the apparatus, for the sake of simplicity, as applied to a
single steam boiler, but, as will be readily understood, the discharge pipe from
the feed pump may communicate with two or more boilers, as is very commonly
the case in feeding boilers, and the suction pipe of the return pump may be in
communication, in the manner above described, with each of two or more boilers.
Dated this 23rd day of December 1897.
STEPHEN WATKINS,
Wolverhampton, Agent for the Applicants.
Novel or Improved Apparatus for use in Maintaining the Water in a
Steam Boiler, or in each of a Number of Steam Boilers, at, or
Approximately at, a Constant or Desired Level.
We, JOSEPH EVANS and WILLIAM EVANS, trading together in co-partnership as
Joseph Evans and Sons, of Culwell Works, Heath Town, near Wolverhampton,
in the County of Stafford, Hydraulic Engineers, and ABRAHAM HOPWOOD, of
3, Culwell Terrace, Cannock Road, Wolverhampton, aforesaid, Engineer, do hereby
declare the nature of this invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:
Apparatus forming the subject-matter of this invention is devised, more
especially, for use with watertube boilers, in which the water level is liable to
considerable fluctuation; but the apparatus may be used, also, with advantage,
with steam boilers generally.

page_text: Apparatus constructed according to this invention, comprises, as essential
features, a feed pump or injector, which may be of any ordinary or convenient
description, and a pump, hereinafter termed the "
return " pump, of which, the
suction pipe or passage communicates with the interior of the boiler at the
normal or desired level of the water therein, and of which the discharge pipe or
passage communicates with a receptacle from which water is drawn into the
feed pump or injector or communicates directly with the suction pipe or passage
of the feed pump or injector. The function of the return pump is to withdraw
from the boiler any water which rises above the normal level therein, and deliver
it either into the receptacle, aforesaid, or directly into the suction pipe or passage
of the feed pump or injector. When the water in the boiler is at its normal
level, the suction pipe or passage of the return pump is open only to the steam
space of the boiler. The delivery valve from the pump, however, or in case the
pump is double-acting each delivery valve or an extra delivery valve in the
common passage from the ordinary delivery valves, is weighted or pressed down,
conveniently by the steam pressure from the boiler exerted upon a piston of
larger diameter than the valve, so that it. cannot be raised except by a pressure
exceeding that of the boiler pressure, and the clearance space or each such space
of the pump is of a capacity which will ensure that any steam passing from the
boiler into the pump will not be compressed sufficiently by the pump to pass such
valve. In lieu of pressing the valve down by steam pressure, it may be pressed
down by a weighted lever, by a dead weight, or by spring pressure.
For the purpose of preventing the entrance of scum from the boiler into the
return pump, the open end of the suction pipe of such pump may be conveniently
formed of a T-shape, of which the head of the T is vertical and the ends thereof
open. The head should, of course, extend for the purpose sufficiently above and
below the portion of the pipe which joins thereinto to insure that, under all
circumstances likely to occur in working, the water level will always be between
the upper and lower ends of the head." In lieu of forming the pipe with a
T-head, the open end of the pipe may communicate with a space which is sur-
rounded by a shield or is enclosed between the end or side of the boiler and a
shield, and in such case the end of the pipe may be formed as a bend, and the
portion of the pipe which passes through the end or side of the boiler be adapted
to be turned axially so that by turning such portion the level of the open end of
the pipe may be varied.
The improved apparatus may be used, also, to assist the circulation of the water,
more especially in the case of a water tube boiler; and such purpose will be best
effected by introducing the feed water into the lower portion of the boiler.
When a feed pump is employed with the return pump, both the pumps may be
operated by the same mechanism, or by mechanism operated from a common
motor; for instance, they may be connected together and be operated by a
single crank or eccentric, or by a single steam cylinder, or they may be operated
by separate cranks or eccentrics which are operated by the same shaft. The
feed and return pumps may be of equal or unequal capacity and in the case of
either, or both, of them, suitable provision may be made for varying the stroke
or speed. Either, or both, of these pumps, also, may be either single or double
acting.
A single pump may be adapted to act both as the feed and return pump, by
providing it with a piston and utilizing one end of the pump for the one purpose
and the other end for the other purpose.
When two separate pumps are used, and both are single-acting, it is preferred
that the one pump shall be discharging while the other is filling, and vice versa,
as in such case the power required to cause the discharge of the feed pump is
furnished, or largely so, by the pressure of the water or steam which issues from
the boiler into the return pump during the suction stroke of such pump.
In order that the invention may be readily understood, we will proceed to

page_text: describe a convenient application of the same which is illustrated, by way of
example, by the drawings herewith.
Figure I is a side elevation of a combined feed and return pump and a longi-
tudinal section through the front end of a water tube boiler shewing the pump
to be connected therewith. Figure 2 is a plan of the pump; Figure 3 is an end
elevation of the boiler; and Figure 4 is a transverse section, to an enlarged
scale, taken on line of Figure 2, looking in the direction of the arrow.
a
A is the feed pump barrel, and B the return pump barrel. The delivery pipe
from the feed pump communicates, through the piping a a², with the horizontal
water cylinders C forming the lower portion of the boiler. The suction pipe b
of the return pump is open to the interior of the cylinder D) which forms the
upper portion of the boiler, and the opening of the pipe within such cylinder is
at the normal or desired level of the water. The delivery valve E of the return
pump is constantly pressed in a downward direction by live steam from the boiler
which passes through a pipe c into the top of a cylinder F within which is a
piston G, of larger diameter than the valve E, which transmits the force exerted
by the steam pressure onto such valve. If the water level in the boiler is below
the opening thereinto of the pipe b, steam only can pass from the boiler into the
return pump; and, to prevent steam passing through the pump, the clearance
space between the suction valve H, delivery valve E, and pump plunger M is
such that any steam which is passed into the pump cannot be compressed by the
working of the pump sufficiently to lift the delivery valve E. When the water
in the boiler rises above its normal or desired level, it is drawn through the pipe b
into the return pump and is delivered through piping into the pipe which
communicates with the suction valve box L of the feed pump; or it might, if
desired, be delivered direct into a tank J from which water is supplied through
a pipe e to the suction valve of the feed pump. In the arrangement specially
illustrated, both the pipe d' which is in communication with the delivery valve
box K of the return pump, and the pipe e which communicates with the tank J,
are directly in communication with one another through the portion of the
suction valve box L of the feed pump which is below the suction
valve, and thus so long as there is a full supply of water from the boiler
for the feed pump no water will be drawn from the tank, but if no water flows from
the boiler, or only an insufficient supply for the feed pump, water will be drawn by
such pump from the tank J; and if there is only an insufficient supply of water
from the boiler the supply which is supplemented from the tank will be raised
in temperature by mixing with the water from the boiler. It will be seen that
the arrangement is quite automatic, as so long as the water is below its normal
or desired level water will be pumped in by the feed pump from the outside source
of supply, but when the water has risen to a height sufficient to cover the open
end of the pipe bit will simply flow into the return pump, from thence into the
feed pump, and be thus returned to the boiler without any addition from the
outside supply; and at intermediate levels, the water which has been withdrawn
from the boiler will be returned thereto together with a proportion of water drawn
from the outside source of supply.
The suction pipe for the return pump extends somewhat into the boiler, as
shewn, and the opening at the end of such pipe is protected from scum by a
shield which is of such depth as will ensure that the water level will not,
under ordinary working conditions, rise above its top or fall below its
bottom. This shield consists conveniently, as shewn in Figure 1, of a vertical
pipe which forms a T-head to the portion of the pipe b which extends within
the boiler.
We have described the apparatus, for the sake of simplicity, as applied to a
single steam boiler, but, as will be readily understood, the discharge pipe from
the feed pump or injector may communicate with two or more boilers, as is very
commonly the case in feeding boilers, and the suction pipe of the return pump

page_text: may be in communication, in the manner above described, with two or more
boilers.
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. Apparatus for use in maintaining the water in a steam boiler, or in each of
a number of steam boilers, at, or approximately at, a constant or desired level,
which automatically operates, when the level of the water unduly rises, to with-
draw water from the boiler or boilers and supply the same direct to the suction
passage of the feed appliance forming part of the apparatus, and of which the
feed appliance automatically operates to supply additional water to the boiler or
boilers if the water level therein unduly falls, substantially as described.
2. Apparatus for use in maintaining the water in a steam boiler, or in each of
a number of steam boilers, at, or approximately at, a constant or desired level,
which comprises a feed pump or injector for supplying water to the boiler and
a return pump of which the suction pipe or passage communicates with the interior
of the boiler, or boilers, at the normal or desired level of the water therein, and of
which the discharge pipe or passage communicates with the suction pipe or
passage of the feed pump or injector, or with the tank from which such feed pump
or injector draws, substantially as described.
3. In apparatus such as and for the purpose set forth in Claim 2, the delivery
valve of the return pump, or each delivery valve, or, in the case of a double-
acting pump, a delivery valve in the passage-way beyond the ordinary delivery
valves which is pressed down or weighted down sufficiently to ensure that when
steam only is within such pump it cannot be compressed sufficiently to raise such
valve, substantially as described.
4. Apparatus for use in maintaining the water in a steam boiler, or in each
of a number of steam boilers, at or approximately at, a constant or desired level,
substantially as described and illustrated, by way of example, by the drawings
herewith.
Dated thin 02-7 da
1000