Improvements in Double-beat or Equilibrium Valves.
Year: 1898

page_text: Date of Application, 26th Mar., 1898
Complete Specification Loft 17th Doc 1800 Accented 25th Mar
1000
PROVISIONAL SPECIFICATION.
Improvements in Double-beat or Equilibrium Valves.
We, RESTAL RATSEY BEVIS, Junior, of 2, Boundary Road, Birkenhead, in the
County of Chester, Engineer, and JOSEPH HAMILTON GIBSON, of 11, Glenalmond
Road, Egremont, in the County of Chester, Engineer, do hereby declare the nature
of this invention to be as follows:-
This invention has reference to valves of the double-beat type, that is, valves
having two faces in parallel planes at certain distances apart, upon a spindle or
body connecting them together, the valve case in connection with which the valve
works being provided with two seats corresponding with the valves, so that when
the valve is closed, the two valve seats rest upon their respective seats of the valve
case; while the pressure of the steam or fluid which they control, acts upon one
side of one valve, and the opposite side of the other, and accordingly as the two
valves are proportioned in area, on which the steam acts, so will they be more or
Jess in equilibrium.
For convenience, the invention will be described as applied to a double-beat or
equilibrium valve, adapted to control the flow of steam of high pressure, the flow
being from the outside of the chamber within the two valves, into this inner
chamber.
According to this invention, the smaller, which say is the lower of the valyes,
is a rigid valve, and works upon its seat in the usual way; whilst the upper valve
is flexible; and when the valve, as a whole, is off its seats, the distances between
the two valve faces is less than the distance between the seats, in order that the
upper and larger valve should come upon its seat in the act of closing, prior to
the lower one; the final closing action of the lower valve upon its seat, being
effected by means of the mechanism by which the valve is operated, and the
flexibility referred to connected with the upper valve, by which this final move-
ment is permitted. The upper area of the valve acted upon by the steam, tend-
ing to close the lower valve, should be, so proportioned that the pressure acting
upon it will just overcome the upward pressure on the lower valve, thereby
enabling this lower valve to be kept steam tight upon its seat, with no, or little,
pressure or load upon the spindle or parts which operates the valve, and so that
the tendency is always to keep the valve closed, whatever the steam pressure.
To open a valve, constructed as above described, power must be used upon the
operating mechanism to lift the bottom valve off its seat or face, first; and then
immediately this is done, the chamber or space between the valve is filled with
steam, whereupon the upper valve is substantially put in equilibrium, and the
valve, as a whole, is then capable of being moved or regulated with ease or little
pressure.
In a double-beat or equilibrium valve, it is known that it is extremely
difficult and expensive work, if not impossible, practically, to make it so that
both valves will rest equally upon their seats, and act properly when in use under
steam or gases of high temperature, no matter how carefully they may be made

page_text: and fitted in the workshop; whereas, by a valve according to our invention, this
equal and proper seating and action is obtained, and without abnormal care or
expense in the manufacture.
1
In one form, the upper flexible valve consists of a ring at the outside, having
upon it the valve face, and adapted to rest upon the valve seat; an inner disc on
the valve stem, approximately the area of the area of the lower valve acted upon
by the steam; and a copper, or other suitable thin metal annular part connecting
these two parts together, and of an undulating or bent section, say having an
annular bulge, to give a free and substantial amount of flexibility. In one form,
the lower valve and upper disc will be formed upon the actuating spindle; and
the annular flexible portion is held upon the upper side of the disc by a nut and
washer, screwing over the spindle; whilst the outer ring or seat is secured to a
vertical edge of the bowed or bulged annular flexible part, by an external clamp-
ing ring and screws.
As a modification of the above arrangement, the lower or bottom valve may
shut first, in which case the steam must, under all conditions of pressure, be
adapted to bend the flexible portion, and bring the top seat down, and close the
top valve.
As modifications of the flexible portion of the valve, this may consist, wholly,
of an annular strip or disc of thin flexible metal of a suitable known kind, and
which may be corrugated or plain, and the under surface of the edge of which
will rest upon the seat of the valve casing, which, in one case, is flat, whilst in
another it may consist of an upwardly projecting ledge; in which case, the surface
in contact with which the flexible portion of the valve would come, will be very
small; whilst in the other cases it would be comparatively large. This annular
disc may be suitably secured to the upper side of the rigid disc of the valve stem
by a clamping ring and screws; or it may be part of the valve itself extending
outside the rigid part, as an attenuated annular flexible edge.
D
1000
CHEESBROUGH & ROYSTON,
Applicants' Patent Agents, 15, Water Street, Liverpool.
Improvements in Double-beat or Equilibrium Valves.
We, RESTAL RATSEY BEVIS, Junior, of 2. Boundary Road, Birkenhead, in the
County of Chester, Engineer, and JOSEPH HAMILTON GIBSON, of 11, Glenalmond
Road, Egremont, in the County of Chester, Engineer, do hereby declare the nature
of this invention and in what manner the same is to be performed, to be particu-
larly described and ascertained in and by the following statement:-
This invention has reference to valves of the double-beat type, that is, valves
having two faces in parallel planes at certain distances apart, upon a spindle or
body connecting them together, the valve case in connection with which the valve
works being provided with two seats corresponding with the valves, so that when
the valve is closed, the two valve faces rest upon their respective seats of the valve
while the pressure of the steam or fluid which they control, acts upon one
side of one valve and the opposite side of the other; and accordingly as the two
valves are proportioned in area, on which the steam acts, so will they be more or
less in equilibrium.
case;
For convenience, the invention will be described as applied to a double beat or
equilibrium valve, adapted to control the flow of steam of high pressure, the flow
being from the outside of the chamber within the two valves, into this inner
chamber.
According to this invention, the smaller, which say is the lower of the valves,

page_text: 0
5
a rigid valve, and works upon its seat in the usual way; whilst the upper valve
3 flexible; and when the valve, as a whole, is off its seats, the distances between
he two valve faces is less than the distance between the seats, in order that the
apper and larger, valve should come upon its seat in the act of closing, 'prior to
he lower one; the final closing action of the lower valve upon its seat, being
ffected by means of the mechanism by which the valve is operated, and the
lexibility referred to connected with the upper valve, by which this final move-.
ment is permitted. The upper area of the valve acted upon by the steam, tend-
ing to close the lower valve, should be so proportioned that the pressure acting
upon it will just overcome the upward pressure on the lower valve, thereby
enabling this lower valve to be kept steam tight upon its seat, with no, or little,
pressure or load upon the spindle or parts which operates the valve, and- so that
the tendency is always to keep the valve closed, whatever the steam pressure.
To open a valve, constructed as above described, power must be used upon the
operating mechanism to lift the bottom valve off its seat or face, first; and then
immediately this is done, the chamber or space between the valve is filled with
steam, whereupon the upper valve is substantially put in equilibrium, and the
valve; as a whole, is then capable of being moved or regulated with ease or little
pressure.
In a metallic double-beat or equilibrium valve, it is known that it is extremely
difficult and expensive work, if not impossible, practically, to make it so that
both valves will rest equally upon their seats, and act properly when in use under
steam or gases of high temperature, no matter how carefully they may be made
and fitted in the workshop; whereas, by a valve according to our invention, this
equal and proper seating and action is obtained, and without abnormal care or
expense in the manufacture.
In one form, the upper flexible valve consists of a ring at the outside, having
upon it the valve face, and adapted to rest upon the valve seat; an inner disc on
the valve stem, approximately the area of the area of the lower valve acted upon
by the steam; and a copper or other suitable thin metal annular part connecting
these two parts together, and of an undulating or bent section, say having an
annular bulge, to give a free and substantial amount of flexibility. In one form,
the lower valve and upper disc will be formed upon the actuating spindle; and
the annular flexible portion is held upon the upper side of the disc by a nut and
washer, screwing over the spindle; whilst the outer ring or seat is secured to a
vertical edge of the bowed or bulged annular flexible part, by an external clamp-
ing ring and screws.
As a modification of the valve arrangement, the lower or bottom valve may
shut first, in which case the steam must under all conditions of pressure, be
adapted to bend the flexible portion, and bring the top face down and close the
top valve.
As modifications of the flexible portion of the valve, this may consist, wholly,
of an annular strip or disc of thin flexible metal of a suitable known kind, and
which may be corrugated or plain, and the under surface of the edge of which
will rest upon the seat of the valve casing, which, in one case, is flat, whilst in
another it may consist of an upwardly projecting ledge; in which case, the surface
in contact with which the flexible portion of the valve would come, will be very
small; whilst in the other cases it would be comparatively large. This annular
disc may be suitably secured to the upper side of the rigid disc of the valve stem
by a clamping ring and screws; or it may be part of the valve itself extending
outside the rigid part, as an attenuated annular flexible edge.
Examples of valves according to this invention are illustrated in the accompany-
ing drawings. In these, Figure 1 is a sectional elevation shewing a complete
valve. Figure 2 is a detail of the upper part of the valve shewn in Figure 1.
Figure 3 is a detail to a larger scale of the flexible disc shewn in these figures.
Figures 4 and 5 are modifications of flexible discs.
In the illustrations of the invention given by these figures, the flexible portion

page_text: or disc referred to rests directly at its periphery or outer part, upon the upper
seat of the valve casing:
Referring to the drawings, a denotes the valve casing generally, and b is its
inlet, and c its outlet steam branch, respectively. d is an annular seat box, in
the openings, at the top and bottom of which, the valve works. .e designates the
valve generally, f being its lower face, which works in connection with the lower
seat inside the box d, and h the flexible disc, which works in connection with the
outer upper surface of the box d, forming the seat to this disc.
Referring now more particularly to the details shewn in Figures 2 and 3-which
are views of the upper part of the valve shewn in Figure 1, to a larger scale-
the flexible disc h consists of a plain or flat inner part, and an outer corrugation
at and about the periphery, and the actual edge of this corrugation rests on the
upper surface of the box d.
The under side of the inner flat portion of the disc h rests and bears on its annular
strip of the body of the valve e, the strip being preferably larger, or not smaller,
in diameter than the opening in which the lower part, f, works in. The disc is
held in place above by a nut j, screwed on to the stem k of the valve, and a disc j¹
pressed down and held in position by this nut. The outer part of the under sur-
face of the ring j' tapers upwards, leaving a gap between it and the disc h to
allow it to move upwards in case of play or movement in this direction being
required.
.
The disc may be of copper, phosphor-bronze, or other suitable material.
In the modification shewn in Figure 4, the disc h is a plain one, and it rests
on the valve seat, by its under-surface, at the periphery; the seat in this case
being an upwardly projecting rib d' on the upper face of the box d.
The modification in Figure 5 is very similar to that shewn in Figure 4, except
that the disc at its edge is bent down; and its outer edge actually rests on an
inwardly coned seat on the box d.
In operation, the valve as a whole will be moved onto and off its seats by a
valve spindle and screw, connected with the head of the valve, or in any suitable
way; and assuming the valve to be off its seat, in the action of closing it, by reason
of the two valve faces-the disc h at the top, and the valve disc f below-being
a less distance apart than the distance apart of the valve seats, the upper flexible
disch will come upon its seat first; and then by the further operation of the
opening and closing mechanism, the lower disc f is brought on to its seat. In
this latter movement, the disc h, being flexible, bends, and enables this final closing
action to take place. Furthermore, the area of the upper valve acted upon by the
steam, tending to close the lower valve should be such that the pressure acting
upon it will just overcome the upward pressure on the lower valve, thereby
causing both the valve faces to be kept upon their seats, and steam tight; and
with little or no pressure upon the valve spindle. By this automatic closing
action, the tendency is to keep the valve closed, no matter what the pressure is.
By the construction shewn, it will now be seen, that a want of accuracy in the
two valve seats as regards the parallelism of their planes, or their being a given
distance apart (no matter how accurately or well it may have been made), due to
the high temperature of high pressure or superheated steam, and to expansion and
contraction; or a want of accuracy in the valve itself due to these causes, are met
and rendered of no moment, and a valve of the type referred to, having the
qualities and characteristics described, provided.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, we declare that what we
claim is:-
a
1. A double beat or equilibrium valve in which the valve proper comprises
rigid face portion and a flexible face portion, these parts having a normally smaller
distance apart, than the distance apart of the valve seats in connection with which
they work; substantially as set forth.

page_text: 2. In a double beat or equilibrium valve, a box, as d, within the valve case,
having two openings; and a valve proper consisting of a lower rigid part f, con-
trolling one of the openings, and a flexible disc portion, h, controlling the other
opening, the said rigid and flexible parts of the valve being connected together,
and constructed and adapted to operate substantially as set forth with reference
to the drawings.
3. Double-beat or equilibrium valves having parts constructed particularly as
shewn in and set forth with reference to the drawings.
• Dreamber 1898.
CHEESBROUGH & ROYSTON,
Applicants' Patent Agents, 15, Water Street, Liverpool.