An Improved Automatic Feed Water Regulator for Steam Generators.
Year: 1896

page_text: Date of Application, 5th Aug., 1896-Accepted, 24th Oct., 1896
;
An Improved Automatic Feed Water Regulator for Steam
Generators.
☐ We, AUGUSTIN NORMAND Engineer JACQUES AUGUSTIN NORMAND Engineer
FRANÇOISE ELISABETH NORMAND.Gentlewoman and MARIE EMILIE NORMAND
Gentlewoman all of 67 Rue du Perrey Le Havre in the Republic of France and
PIERRE SIGAUDY Engineer of 31 Boulevard d'Harfleur Le Havre aforesaid 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:
When the amount of steam generated in a boiler is considerable, relatively to the
evaporation surface and when the feed water has to be divided between a
number of boilers, it is desirable to regulate the admission of such feed water
automatically; and the apparatus for this purpose should combine the following
features, viz. :-
(1) The operation of the apparatus should be very reliable, since, when an
automatic apparatus is employed the firemen will not watch the water-gauges so
closely as they would do, if such apparatus were not provided. The apparatus
should therefore, be sufficiently powerful to actuate the distributing gearing with
certainty, and it should be in a position such as to enable the efficiency of its
operation to be tested at any time; and
(2) When used in connection with marine boilers, the apparatus should be as
independent as possible of the changes of level of water in the boiler owing to the
motion of the vessel.
In the accompanying drawings
Figures 1, 2, 3, 4 and 5 represent one of the forms in which this invention may
be carried out; aud
and
Figures 6, 7 and 8 represent it in another form.
Referring first to the form Figures 1 to 5
Figure 1 is a vertical section of the improved apparatus.
Figure 2 is another vertical section thereof taken on the line X X¹ Fig. 1.
Figure 3 is a plan of the apparatus, with the cover removed.
Figure 4 is a vertical section of the apparatus taken on the line Y Y¹ Fig. 1.;
Figure 5 is a horizontal section (taken on the line Z Z' Fig. 1.) of the part of the
apparatus wherein the feed-regulating cylindrical slide valve E moves.
The apparatus consists of a chamber or reservoir A in which is a float B
balanced by a counterweight C, to which it is connected by the beam D. When
the chamber A is filled with water, the float B is in its highest position, as shewn
in the drawings; but, when the said chamber A, is empty, the float B, descends to its
lowest position. When the said chamber A, is partially filled with water the said
float B takes up intermediate positions."
The slide valve E is connected to the float B and therefore is raised and lowered
with the said float, altering, according to its position, the section of feed water inlet
in the boiler.
There is a central perforation through the axis of the valve so that pressure in
the valve casing beneath the valve and in the chamber A is the same. The feed
water enters at F and issues at G, on its way to the boiler.
The apparatus is preferably placed above the normal level in the boiler to
which it is fitted at such a height that the discharge-pipe H from the vessel A
:

page_text: is inclined downwards gradually to its extremity I which opens at, or about, the
normal level of the water in the boiler, and is horizontally, near the centre of the
evaporation surface of the water which centre is independent of the motion of
the vessel. The diameter of this pipe should be large enough to afford a passage
simultaneously to the water that is discharged and to the steam that takes its place.
Instead of a single pipe, there may be two such pipes, one for water, secured to
the lower part of the vessel A, and the other for steam, this latter pipe being of
much smaller diameter than that for water and being secured to the upper part of
the said vessel; the lower orifices of both pipes being at the same height, at, or
near, the normal level of the water in the boiler. It will be assumed, in the
following description that a single pipe is used. At the top, the chamber A also
communicates through a very small orifice in the cock J, with a space or chamber,
wherein the pressure is less than that prevailing in the boiler, such, for example, as
a feed-water heater constructed upon Normand's system, the intermediate receivers
between the cylinders, the cold water cistern, or the condenser, or even the
atmosphere itself. The pressure within the chamber A, therefore, is always
somewhat less than the pressure in the boiler, and a constant flow of water and
steam is created between the boiler and the chamber A.
The operation is as follows:-
If the water-level in the boiler rises above the orifice I of the pipe H, the
chamber A becomes filled with water owing to the partial vacuum produced by
the escape of steam or water through the small orifice in the cock J (for which
1 to 4 square millimetres will be a sufficient sectional area); the valve E rises, and
closes and only allows the feed-water to pass through a narrow orifice K. As the
water level sinks in the boiler, owing to insufficient feeding, it eventually uncovers
the orifice I of the pipe H; the water then leaves the chamber A.; the float B
and valve E descend, and the passage for the feed water supply to the boiler is
opened.
The water level in the boiler around the orifice I of the pipe H, is preserved
from injurious fluctuation or disturbance due to the rising of steam bubbles, or to
the motion of the vessel, by means of a chamber or space L closed on all sides and
only communicating with the volume of water, contained in the boiler, through the
orifice M, situated at its lower part.
The apparatus is secured to the boiler by means of a cock N. The closing of the.
cocks N and J enables the apparatus to be isolated when required.
A rod P, connected to the counterpoise weight C serves to indicate the movement
of the several movable parts, and enables them to be operated, either directly by
hand or through the medium of a lever, or the like, whenever it is required either
to ensure the proper operation of those parts, or to increase the feed water supply
in an emergency. The rod P should be of small diameter and its packing in the
stuffing box should offer ouly such a minimum resistance to motion, as is absolutely
necessary to ensure tightness. The said rod P, may be dispensed with where it is
found to involve too great a sacrifice of the sensitiveness of the apparatus. Or
the effect of the friction between the rod P.and its stuffing box may be counter-
acted by increasing the weight of the counterpoise C, and reducing the length of
the arm of the beam, or lever, D, from which it is suspended.
The apparatus will act in a satisfactory mauner with somewhat considerable
variation in the level, or height, of the orifice I, of the pipe H, in relation to the
normal water level in the boiler but herein is given what I consider the most
favorable conditions, and those under which the apparatus will give the best
results, if applied to each constituent boiler of a battery of boilers all fed from
one and the same feed water supply..
It is well known that in a battery of this class the feed water is the more evenly
divided, the narrower the sectional area of the orifice, through which such water is
discharged into the boiler; for there is such an increase of pressure, between the
feed-pipes and the boilers that the discharge takes place almost uniformly in all,
whatever may be the slight differences of pressure between the different boilers

page_text: and the want of symmetry between the connections of the several boilers with the
feed water collecting pipe. The production of steam in all the boilers, however,
is not the same, and the possible want of symmetry of the steam valves in relation
to the steam collecting pipe, considerably increases the difference of production.
The object of the feed regulator is to remedy this cause of instability, of the water
levels.
Supposing now that the orifices I of the pipes. H in the several boilers of the
battery, are arranged uniformly somewhat beneath the normal level-Generally,
the feed regulators are filled with water, the slide valves are closed and the boilers
are fed solely through a supply orifice of a very small sectional area. There is
therefore a greater, or lesser, éxcess of pressure, say from 1 to 3 atmospheres,
between the feed water supply aud the boilers; and these are the conditions above
referred to, upon which depends as uniform, a division of the feed water, as possible,
between the several boilers of the battery. When the water level in any one of
the boilers descends below the orifice I of the pipe H, the feed water regulator of
such boiler is emptied; the float in descending opens the slide valve, the discharge-
port of which becomes four, five, or 6 times larger (for example), than it was when
the slide valve was closed and, accordingly, the amount of water fed to that boiler
becomes four, five, or six times greater than in the other boilers. The water level
rises the more rapidly, the greater this proportion or ratio, and the moment it
attains the orifice I of the pipe H the chamber of the apparatus is filled with water
and the slide valve closed.
Now assuming, on the other hand, that the orifice 1 of the said pipe H is situated
somewhat above the normal level of the boilers. The feed-regulators are then
generally empty, and the difference of pressure between the feed water supply and
the boilers will therefore be very slight, which is a rather unfavourable condition,
as before stated, for the equal division of the feed water among the several boilers
of the battery. The level may sink rapidly in a boiler without causing any change
to take place in the feed water supply, since the feed-regulator only acts when the
water level rises, whilst, previously its operation was brought about by the descent
of the water level. Now it will be understood that it is far more desirable that
the feed regulator should resist, or counteract, an abnormal lowering of the water
level, than an abnormal rising of the same. When the level rises in any one boiler
of the battery above the orifice I of the pipe H, the feed regulator becomes filled,
the cylindrical slide valve closes owing to the rising of the float, and the amount of
feed water admitted to that boiler is, in consequence, considerably reduced in
comparison to what it is in the remaining boilers of the battery.
Again if the orifice I of the pipe H be at the same height, as the normal level,
the inconveniences attaching to the arrangement previously described are to a
great extent remedied, although the conditions are still less favourable than they
were in the arrangement first described, that is to say, the arrangement wherein
the orifice referred to is situated somewhat below the normal level.
In short, if stability of level be taken to mean the greater, or less, rapidity with
which such level is restored to its normal height when it happens to be lowered,
such stability will be far greater when the orifice I of the pipe H, is situated a
little distance below the normal level, than when it is arranged above that level.
In view of the foregoing statements it will be readily understood that the feed
regulator, according to this invention, complies with the conditions laid down as
being those upon which the proper operation of all feed regulators depends.
It is sufficiently powerful to properly set the distributing or valve gearing in
operation, inasmuch as it acts in virtue of the total weight of the water displaced
by the float, whereas, in the majority of existing feed water regulators, a fraction
only of the volume of the float becomes the determining cause of the motion, and
a considerable change of level is necessary to produce an appreciable amount of
power. In the apparatus according to this invention, however the slightest change
of level is sufficient to set in operation, or give effect to the maximum power, as
applied to the operation of the distributing gearing.
.

page_text: The improved apparatus may at any time be disconnected from the boiler and
tested. The orifice I of the pipe H being situated in the vicinity of the centre of
the evaporating surface, the level of the water in that portion of the apparatus is
independent of any of the movements of the vessel, on which the feed regulator
is-employed.
Besides, this apparatus enables a feed pump common to a number of boilers to
be employed a circumstance which affords very material advantages, admitting, as
it does, of the mechanism being greatly simplified, and of a considerable amount of
fuel being saved.
A somewhat modified arrangement, based upon the same principle, is illustrated
in Figures 6, 7 and 8.
Figure 6 being a vertical section of the arrangement:
Figure 7 an external view of the same; while
Figure 8 represents a double seated and balanced valve which may be substituted.
for the cylindrical slide valve shown in Figure 6.
In this modified form, the apparatus consists of a chamber A. within which a
float B is adapted to move; such float being mounted upon a beam or lever f, the
short arm of which operates a rod, connected to the cylindrical slide valve E
sliding within a cylinder fitted with two nozzles or jets F and G which, according
to the position occupied for the time being by the slide valve, may be connected
by orifices, or ports, varying in sectional area. The float B is balanced by a
counterpoise weight C acting upon the end of a lever or beam f'.
In order to impart considerable sensitiveness to this apparatus all its parts are
perfectly well balanced, and so devised that friction between them is reduced to a
minimum. The balancing weight C is situated between two mutually repelling
springs R R', serving to overcome or absorb gradually its momentum. A rod P
connected to the said balancing lever and terminating in a handle enables the
apparatus to be controlled by hand either for the purpose of ensuring the proper
operation of the movable parts, or for increasing the amount of feed water supplied
to the boiler on an emergency. Nuts e and el resting upon the case of frame c,
enable the initial position of the cylindrical slide valve, when inoperative, to be
tentatively adjusted in relation to the orifices of the cylinder.
The general statements herein before made in reference to the apparatus shewn
in Figures 1, 2, 3, 4 and 5 also apply to the arrangement shewn in Figures 6, 7
- and 8, the operation of both being the same.
The feed regulator in either of the forms shewn and described, will also operate
satisfactorily if placed below the water level. In this case the escape cock should
be placed in the lower part of the reservoir, and the water discharged, substituted
by steam, or water, as the case may be, all of which takes place under the same
conditions as before.
There are already a number of arrangements in existence which cause feed
water to be supplied to boilers by means of a pipe similar to the pipe. H opening
in the vicinity of the normal water level of the boiler, but in all these the motor
fluid, whether water or steam, acts upon a special feeding device, whereas in the
apparatus forming the subject of this invention the motor fluid, whether water or
steam, merely modifies the sectional area of the feed water supply orifice in each
constituent boiler, of a series or battery; such feed water being supplied from. a
perfectly independent feeder.
It will be understood that the proportions dimensions, and accessory devices, may
vary according to requirements without departing from the principle of the
invention.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. A feed water regulator formed of a float adapted to move in a chamber, or
reservoir, connected both with the boiler through a pipe or pipes, opening in the

page_text: vicinity of the normal water level of the said boiler, and with a space wherein the
pressure is always lower than that of the boiler so that a constant discharge or
feed takes place from the boiler into the reservoir and the fluid thus discharged
(either steam when the level in the boiler is too low, or water when that level is
too high) displaces the float the motion of which is utilized in varying the section
area of the feed water inlet to the boiler.
2. The arrangements herein before described by way of example, and illustrated
in the accompanying drawings.
Dated this 5th day of August 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents..