Improvements in Water Feed Apparatus for Steam Boilers.
Year: 1899

page_text: Date of Application, 18th July, 1899-Accepted, 19th Aug., 1899
COMPLETE SPECIFICATION.
Improvements in Water Feed Apparatus for Steam Boilers.
I, FRANZ JOSEPH WEISS, of Weiherweg 54, Basel, Canton Basel, in the Swiss
Confederation, Civil 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:-
This invention relates to improvements in automatic feed apparatus for steam
boilers of the kind described in the Specification of prior British Patent No. 19402
A.D. 1898 and is illustrated in the accompanying drawing the figures of which are
hereinafter referred to.
According to the said prior specification the arrangement is such that the stoker
may set the feed pump in motion to feed the boiler or in case of his absence or
omission to do so the feed will be automatically started directly, as soon as the
water falls to a predetermined minimum level. This is effected according to the
above mentioned prior specification by connecting the steam cylinders of the feed
pump with the steam boiler by two pipes, one having a stop valve and leading into
the steam space of the boiler and the other being constantly open and leading to
the normal or to the lowest water level in the boiler. To permit of the operation
of the feed pump with dry steam by opening the stop valve and causing it to feed
to any desired extent so as to cause the water to rise above the normal level in
the boiler whereby the open pipe will be under water in the boiler it is necessary
to arrange this latter pipe to rise in an upward direction from the boiler as
otherwise water will enter the steam cylinder of the pump and the latter could not
then be worked at a normal quick speed. To enable however a downwardly
directed tube to be employed it will be necessary to temporarily close the same
without impairing the safety of the feed arrangement.
to
Now according to my present improvement I provide at the junction of the
pipe a with pipe e Figure 1 a reversing valve H designed in such a manner that
in one end-position Figure 1, the pipe e, and in the second end-position
is closed from
leads
Figure 2, the pipe a
the pipe which
the steam cylinders D of the feed pump D E; while furthermore this valve H in
any intermediate position between the two end-positions never entirely closes the
two pipes a and e see Figure 3.
If the valve H is a slide-valve, whether plane or cylindrical, a disc, or a cock-
valve the before mentioned conditions are ensured by forming the obturating
portion, in the direction of the movement of the valve so that in any of the inter-
inediate positions of the valve the pipes a and c are not fully closed, this obturat-
ing portion being however so arranged when in one extreme position as to close
the pipe a and when in the other extreme position to close the pipe e entirely.
By way of example I have shown the valve H as a rotary valve or cock in
Figures 1, 2 and 3 and in Figure 4 I have shown it in the form of a piston-valve
the piston of which is adapted to be moved endwise by hand by means of the
rod m.
If it be desired to employ a lift-valve, as shown in Figure 5, it is advantageous
to arrange the inlet openings at the two pipes a and e in the interior of the valve

page_text: shell at opposite points to each other with a valve disc v between them in such a
manner that each of these pipes can be made to communicate separately with
the pipe f which is also connected with the valve shell. This valve acts in
the manner of a three-way cock and in its left hand end position the valve disc v
closes the inlet of pipe a and fully opens pipe e for communication with pipe f,
while in its right hand end position the pipe e is closed and pipes a communicates
with pipe f; in all intermediate positions of the valve v both the pipes a and e
are in communication with pipe f.
The action of the various valves is the same and I will describe this action
with reference to Figure 1 which shows a rotary valve.
In order to start the feed apparatus the valve H is turned from the position
shown in Figure 1 to that in Figure 2 so closing the pipe a which opens into the
boiler at the normal water level, while at the same time opening the pipe e.
This causes dry steam to be supplied to the cylinders D of the feed pump DE
and so operate the pump at full speed whereupon the pump plunger E draws in
water from the water tank F through the suction pipe and forces it through
the pipe c into the boiler C. To stop the feed the valve H is returned into its
initial position Figure 1 so closing the steam pipe e while opening the pipe a
which opens into the boiler at the point of either the normal, or the lowest water
level A-B. As however the water level in the boiler is now above the pipe a
it follows therefore that water will enter the steam cylinders of the feed pump
so that the pump will be caused to work slowly owing to the greater friction
through the water than with steam in the pipes and steam cylinder. This con-
tinues till the water level in the boiler falls and feeding is again required for
which purpose in the ordinary course of working the valve is reversed into the
other position.
'
If the stoker or attendant forgets to feed by reversing the valve then one of
three positions of this valve are likely to exist according as to how it has been
last set, viz.:
1. The valve may have been left in the end position Figure 1, or
2. It may have been left in any intermediate position between the end positions
as is indicated in Figure 3; or
3. It may have been left in the end position Figure 2; no other position can
possibly exist.
CASE 1.
In this position of the valve the steam pipe e is closed and pipe a is open;
while the water level in the boiler is above the normal level A-B the feed-
pump receives water under pressure from the boiler and is thus kept working very
slowly by the water only. If now the water level in the boiler falls to or below
its normal level the pump is supplied with steam through the pipe a and then
works at full speed thus quickly raising the water level in the boiler to the normal
and when this passed water will enter the steam cylinder and cause the pump
to slow down, then the water level in the boiler falls gradually until steam passes
through the pipe a and sets the pump going full speed and so on in succession.
Thus by this arrangement the water level in the boiler is automatically kept
within narrow limits and a deficiency of water in the boiler cannot take place.
CASE 2.
In this case the valve H is left in its middle position Figure 3 so that both the
pipe a and e are partly or fully open. If now the water level is below the normal
A B obviously steam will pass through both pipes e and a into the steam cylinder
of the feed pump thereby causing the latter to work full speed and quickly restore
the normal water level. Directly the water raises above the pipe a the pump will
be fed through pipe e with steam and with water through pipe a and while thus
working with a mixture of steam and water its speed will be reduced to a speed
between the highest speed with steam and lowest speed with water only. If

page_text: the water level falls again below the normal both pipes a and e again supply
steam to the pump causing it to work with full speed and bring the boiler water
up to its normal. Thus a deficiency of water in the boiler cannot occur.
CASE 3.
Should the valve H have been left in the position shown in Figure 2 for feed-
ing, it is clear that the pump will continue working with steam and so fill the
boiler. This however constitutes no danger because the boiler pressure is not
thereby increased but rather caused to fall owing to the large amount of com-
paratively cool feed water forced into the boiler.
Therefore any danger caused by low water in the boiler is entirely excluded.
Finally it may be mentioned that the pipe f between the steam cylinders D
of the feed pump and reversing valve H is of such a diameter, or is provided
with a contraction so as to cause the pump, when working with full steam sup-
plied either through pipe e or pipe a or through both not to run at more than
normal speed.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
-
In a boiler feed apparatus the provision of a reversing valve H at the point
of junction between the pipes e and a to enable either of these two pipes e and a
to be closed separately but not simultaneously the object being to prevent the
valve being left by mistake in a wrong position and owing to forgetfulness
allow the water level in the boiler to fall below the normal level.
www
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.