Improvements in Lift Valves, Safety Valves, and analogous Valves,
Year: 1899

page_text: Date of Application, 29th Apr., 1899
Complete Specification Left, 29th Jan., 1900-Accepted, 21st Apr., 1900
PROVISIONAL SPECIFICATION.
Improvements in Lift Valves, Safety Valves, and analogous Valves,
We, RESTAL RATSEY BEVIS, Junior, of 2, Boundary Road, Birkenhead, in the
County of Chester, Engineer, and JOSEPH HAMILTON GIBSON, of 2, Dalton Road,
Magazines, Liscard, in the County of Chester, Engineer, do hereby declare the
nature of this invention to be as follows:-
1
This invention has reference to stop valves, safety valves, and valves working
under analogous conditions, and of the type variously known as "int-valves,
mushroom-valves," or popp-valves;" and it has primarily for its object to
provide improvements, or a construction by which steam-tightness of valves
of this kind, which are subjected to high pressure, and high temperature steam,
such as is now used on steam vessels, can be comparatively easily effected and
maintained; and at the same time, without requiring abnormal power to open
and close the valves, which is frequently required with the present constructions
of such valves; and also which will obviate the cost and time of "grinding" the
valve to its seat.
With the high pressures and temperatures of steam now obtained in steam-
ships, and other installations of steam plant of large size, with large steam
pipes and valves, it is increasingly difficult to make such valves steam tight by
the ordinary means and construction, namely, by a valve having a coned face.
ground to a perfect fit, and forced on to its seat by screw gear or its equivalent;
the difficulty being due, mainly, to the distortion of the valve box, and perhaps
the valve, caused by the high temperature and pressure of the steam.
The result of this defect, besides being an engineering defect in itself, is
serious in that, these leaking valves are the cause of the loss of a large amount
of fresh water, by leakage of the steam past the valves when the valves are sup-
posed to be shut; in the case of steam ship machinery, the loss of fresh water is
a serious matter.
According to this invention, the valve seat of valves of the kind described, is
flexible, that is, it is an annular flexible seat; and the valve face-which may be
flat-rests on the edge, which in one form is upturned, of this annular seat. And,
further, in connection with a valve provided with this improvement, there is a
stop between the valve proper and its case, or a part connected with the seat,
which is so arranged as to come into action in the closing of the valve, soon after
the valve has come in contact with its flexible seat, and has moved it from its
normal position when the valve is open. This stop may consist of an annular
projection on the valve periphery, which comes onto a part surrounding the flex-
ible seat, say a ring holding the annular flexible seat to the metal which supports
it. Or, this stop may consist of projections or parts inter-spaced round the valve,
which act as stops, and limit the amount of movement of the valve after it comes
on to its flexible seat.
In one form say for the main stop valve, the flexible seat may consist of an
annular disc with its inner edge, constituting the seat proper, turned up towards
the valve, and bevelled; and it is supported on the upper edge of the flange of a

page_text: seat lining or bush in the steam way in the valve case, and fixed thereon by a ring,
which fits over it; the ring being held down by studs, or the like. The part of
this flange which lies under the inner part or edge of the flexible seat is rounded
off or cut away in such a manner as to allow the flexible seat disc to bend, and
move downwards, when the valve is pressed down on it; and so that in this action,
the seat would bend down gradually onto its support, and would bring the annular
surface of support inwards, the further it is pressed down.
In the case of safety and like valves constructed according to this invention,
the flexible annular seat may be pressed down onto its supporting part by an
internal lantern, having openings tor the escape of steam, which is pressed down
onto the upper side of the seat, and held there. And outside the face of the valve,
at the edge of the seat, the usual pendant annular lip is provided; and again out-
side this, the construction by which the limit of movement of the valve, and deflec-
tion of the valve seat, after the valve has come upon it, is provided, similarly as
in the case first described.
In action, in closing the valve, the valve first touches the inner edge of the flex-
ible seat, which it presses down a very slight amount; and then the rigid exter-
nal projection, or stops, come into action, and further movement of the valve is
stopped. The moment the pressure of steam from the upper side of the valve is
diminished or taken off by the closing of the valve, the pressure underneath in
trying to escape, presses the flexible seat against the valve face with greater inten-
sity, and makes a perfectly tight joint; and hence the steam pressure itself will
make and retain the final closure, the flexibility of the seat enabling the steam
to press it up to the valve all round, even if the face be somewhat distorted, or
not truly in the same plane.
In the opening of the valve, the flexible seat naturally tends to rise with the
valve, but is prevented from doing so by the ring or part which holds it down.
A suitable material for the flexible annular seat is a hard metal, such as ham-
mered phosphor bronze, or analogous, or equivalent metals.
As a modification, the seat of a valve may be solid with a part on which the
valve rests, made more or less flexible by a slit being cut into it annularly, just
below the part on which the valve sits, and so that the seat becomes an annular
cantilever; or, this annular cantilever flexible seat may be cut or formed out of
the solid seat body, and project inwardly, in any suitable way. On the back of the
valve, or at its edge, projecting stops in the form of ribs, or an annular stop piece,
will be provided, to limit the flexion of the seat positively.
With regard to the means of actuating the valve in the case of a stop valve, it
may consist of a screw spindle, acting in connection with the valve in any known
suitable way; while in the case of safety valves, the spring or weight may act
upon the valve also in any of the known suitable ways.
Dated this 28th day of Anril 1899
CHEESBROUGH & ROYSTON,
Applicants' Patent Agents, 15, Water Street, Liverpool.
We, RESTAL RATSEY BEVIS, Junior, of 2, Boundary Road, Birkenhead, in the
County of Chester, Engineer, and JOSEPII HAMILTON GIBSON, of 2, Dalton Road,
Magazines, Liscard, in the County of Chester, Engineer, do hereby declare the

page_text: 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 has reference to stop valves, safety valves, and valves working
under analogous conditions, and of the type variously known as "lift-valves,
mushroom-valves," or popp-valves," and it has primarily for its object to
provide improvements, or a construction by which steam-tightness of large valves
of this kind, which are subjected to high pressure, and high temperature steam,
such as is now used on steam vessels, can be comparatively easily effected and
maintained; and at the same time, without requiring abnormal power to open
and close the valves, which is frequently required with the present constructions
of such valves; and also which will obviate the cost and time of "grinding "the
valve to its seat.
With the high pressures and temperatures of steam now obtained in steam-
ships, and other installations of steam plant of a large size, with large steam
pipes and valves, it is increasingly difficult to make such valves steam tight by
the ordinary means and construction, namely, by a valve having a coned face,
ground to a perfect fit, and forced on to its seat by screw gear or its equivalent;
the difficulty being due, mainly, to the distortion of the valve box, and perhaps
the valve, caused by the high temperature and pressure of the steam.
The result of this defect, besides being an engineering defect in itself, is
serious in that, these leaking valves are the cause of the loss of a large amount
of fresh water, by leakage of the steam past the valves when the valves are sup-
posed to be shut; in the case of steam ship machinery, the loss of fresh water is
a serious matter.
According to this invention, the valve seat of valves of the kind described, is
flexible, that is, it is an annular flexible seat; and the valve face-which may be
flat rests on the edge, which in one form is upturned, of this annular seat. And,
further, in connection with a valve provided with this improvement, there is a
stop which is so arranged as to come into action in the closing of the valve, soon
after the valve has come in contact with its flexible seat, and has moved it from its
normal position when the valve is open. This stop may consist of an annular
projection on the valve periphery, which comes onto a part surrounding the flex-
ible seat, say a ring holding the annular flexible seat to the metal which supports
it. Or, this stop may consist of projections or parts inter-spaced round the valve,
which act as stops, and limit the amount of movement of the valve after it comes
on to its flexible seat.
A suitable material for the flexible annular seat is a hard metal, such as ham-
mered phosphor bronze, or analogous, or equivalent metals.
As a modification, the seat of a valve may be solid with a part on which the
valve rests, made more or less flexible by a slit being cut into it annularly, just
below the part on which the valve sits, and so that the seat becomes an annular
cantilever; or, this annular cantilever flexible seat may be cut or formed out of
the solid seat body, and project inwardly, in any suitable way. On the back of the
valve, or at its edge, projecting stops in the form of ribs, or an annular stop piece,
will be provided, to limit the flexion of the seat positively.
With regard to the means for actuating the valve, in the case of a stop valve, it
may consist of a screw spindle, acting in connection with the valve in any known
suitable way; while in the case of safety valves, the spring or weight may act
upon the valve also in any of the known suitable ways.
The invention will be further described with reference to the annexed drawings,
which illustrate our improvements. In these, Figure 1 is a sectional elevation
shewing a stop-valve according to the invention; and Figures 2 and 3 are sections
shewing the construction of the parts about the flexible seat in detail; whilst
Figures 4 and 5 are details shewing modified forms of flexible seats, on a large
scale.
Figure 6 is a section shewing the invention applied as a safety valve; and
Figures 7, 8 and 9 are sections to a larger scale, shewing the positions of parts

page_text: under different conditions of the valve. Figure 10 shews a portion of the flexible
seat to an enlarged scale.
Figures 11 and 12 are sections shewing two forms of the modification wherein
the annular flexible seat is formed out of the solid seat body.
Referring to these drawings, and more particularly to Figures 1 to 5 in the
first instance, a represents the metallic flexible valve seat; b is the valve; b¹ is an
annular projection on the valve periphery constituting the stop; and c is a ring
on the valve case d in connection with which the stop b¹ operates.
This ring c also serves to hold the annular flexible seat a down onto the metal
of the casing d, it being itself fastened to d by stud bolts and nuts c¹.
The flexible seat a consists of an annular disc of thin metal, such as hammered
phosphor bronze, or the like, and in one form, as shewn in Figures 2 and 4, its
inner edge, which constitutes the seat proper, is turned up towards the valve, and
is slightly bevelled, and the face of the valve in connection with which it works,
is horizontal, or nearly so.
In the modification shewn in Figures 3 and 5, the seat consists of a plain annu-
lar disc, while the valve face is bevelled.
The inner part of the ring c above the scat a, and the metal of the case d
directly below it, is tapered or cut away as shewn, leaving a wedge shaped space
above and below it, to allow the flexible seat disc to bend and move downwards
when the valve is pressed down onto it, and so that the seat in this action would
bend down gently onto its support; the result 'being that the annular surface of
support for the seat would be brought inwards, the further it-the seat-is pressed
down.
In action, in closing, the valve first touches the inner edge of the flexible.
seat u, which it presses down slightly; and then the rigid external stop portion b¹
comes on to the upper edge of the ring c, and further movement of the valve is
stopped: The moment the pressure of steam from the upper side of the valve b
is diminished by the closing of the valve, the pressure underneath in trying to
escape, presses the flexible seat against the valve face with greater intensity, and
makes a perfectly tight joint; and hence the steam pressure itself will make and
retain the final closure, the flexibility of the seat enabling the steam to press it
up to the valve all round, even if the face be somewhat distorted, or not truly in
the same plane. In the opening of the valve, the flexibility of the seat a naturally
tends to rise with the valve but is prevented from doing so by the metal of the
ring c.
In the details given in Figures 2 and 3, the valve is shewn in the position in
which its face has just reached the flexible seat a; at which point, as the drawings
illustrate, the lower edge of the annular projecting part 6, is slightly above the
upper side of the ring c, against which it ultimately comes.
Referring now to the safety valve shewn in Figures 6 to 10, the construction
and characteristics of this valve are identical with those set forth with reference
to Figures 1 to 5, but with the slight modification, that the stop b¹ is below the
flexible seat a, and rests, when the valve is closed, upon an inner seat e.
In this case, the stop makes a joint with the part e, of such a degree of tightness,
that the calculated pressure of steam designed to act upon the valve, would be
that which acts on an area equal to the interior area of the seat e.
In this case,
water or steam, which might find its way into the annular space between the stop
seat e and the flexible seat a could be exhausted or drawu off through a branchf,
in order that the desired and calculated pressure on the valve should not be dis-
turbed, but remain constant and positive.
Under normal conditions, with the valve closed, the parts assume the positions
shewn in Figure 7, that is, the part 1 of the valve rests upon the solid stop seat e,
and the upper part rests on the edge of the flexible seat a, bending it down
somewhat.
Then, in action, when the pressure of steam exceeds that at which the valve
is set to hold, it first raises the portion b¹ off the stop seat e; when the parts would

page_text: assume the position shewn in Figure 8.
Although the part b₁ is raised off the
stop seat e, the valve is not raised off its true seat, namely, the flexible seat a;
but this seat has followed the valve by its own resiliency, and pressure of steam,
to the position shewn. In this position it will be seen that the area of the valve
which can be acted upon by the steam is somewhat greater than the nett area
acted upon when the part is upon the stop seat e. By the further movement of
the valve d, it rises off the seat a altogether, and when full open the valve and
parts will take the position shewn in Figure 9.
In coming to its seat, after action, the valve will, of course, first come onto
the end of the flexible seat a, and make a steam tight joint, the pressure of steam
forcing the flexible seat onto the valve face as soon as it touches it. After which
the stop part or solid face b¹ moves on to the solid stop seat e, which completes the
closure.
In the modification shewn in Figure 11, the flexible annular seat a is made
out of the solid part or casing d, on which the valve rests, namely, it consists of
a thin annular flexible strip, as shewn, made by cutting a slit a in the metal of
the casing d. In the modification shewn in Figure 12, the annular flexible
seat a is formed out of the solid seat body d, and projects annularly from this
metal in any suitable way.
In both of these cases the degree of flexion is limited by stops, in the form of
ribs b, provided on the back of the valve b, the lower edges of which will come
upon the stop piece or ring c, when the annular seat a is deflected.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:
1. The herein described improvement in valves of the kind herein referred to,
namely, a valve having a flexible metallic seat, and in which the bending or
flexion of such seat is limited by a stop or stops on or connected with the valve
and the valve case or part thereon; operating substantially as and for the
purposes described.
2. A valve of the kind herein referred to wherein a flexible metallic seat is
forced on to the face of the valve when closed, by the pressure of steam in it;
substantially as herein set forth.
3. A valve of the kind herein referred to, comprising a valve b, an annular
flexible metallic seat a, and a stop or stops on said valve: substantially as set
forth with reference to the drawings.
"6
4. The stop-valve" consisting of the parts constructed, arranged, and adapted
to operate as set forth with reference to and shewn in Figures 1 to 5 of the
drawings.
5. The safety valve consisting of the parts constructed, arranged and adapted
to operate as set forth with reference to and shewn in Figures 6 to 10 of the
drawings.
6. The "stop-valve" consisting of the parts constructed, arranged, and adapted
to operate, as set forth with reference to and shewn in Figures 11 and 12, of the
drawings, respectively.
CHEESBROUGH & ROYSTON,
Applicants' Patent Agents, 15, Water Street, Liverpool.