Note: Descriptions are shown in the official language in which they were submitted.
4~3~ :
In the production o-f well flulds, such as oil and/or
gas, from wells situated at remote locatio'ns, it has become the
' practice to employ automatic shutoff valves which are responsive
to the pressure of well fluids so as to be actuated from an opened
condition to a closed condition in the event of loss of well
fluids as may be caused by various circumstances. For example, it
may occur that a well located at sea may suffer damage which will
allow well fluids to flow into the sea, not only resulting in
.
loss of well fluids until the well can be killed, but also resul~
10 ting in contamination of the sea water and the seashore when oil ;
- escapes into the sea and drifts ashore. It is also desirable to
prevent the uncontrolled loss of well fluids from remotely located
onshore wells where damage may occur to the wellhead equipment,
~ resulting in the uncontrolled flow of the well until it can be
- 15 killed
Various valves have been heretofore developed for the ''
purposes of automatically shutting off such a flowing well, at a
subsurface location in the production pipe string, including
sleeve type valves and ball type valves which have a substantially
' 20 fuIl bore opening therethrough and thereby cause no substantial
`~ restriction to flow. ~owever, such ball valves experience opera-
ting difficulties, particularly when they are beiny opened and
the well fluid pressure below the valve, which is holding the valve
:i ' . , ~.. :
closed, is substantia'1, causing a high fr'iction loading between ' ~ '
, 25 the sealing faces and the surface of the ball with which they are -
sealingly engages . Indeed, the operating means for shifting ~'
the ball to an open position may, in some instances, be destroyed. '' ~
Ball valves have been incorporated in subsurface ''''
safety valves, wherein the balanciny valve equalized the fluid
across the closed ball valve before;the ball valve is opened,
, ' , ':' , ,'
. . , , . ~ , .. . . .. . . . .. .. . .
~.~4~i~34
thereby reducing the wear and frictional resistance to ball
actuation.
AS discussed in United States Pa-tent 3,868,995, issued
March 4th, 1975, there is provided an automatic subsurface
shutoff valve of the ball type, wherein the ball is easy to
manipulate from the closed to the open position, notwithstanding
high well fluid pressure tending to hold the valve closed.
More particularly, a control Eluid operated by-pass valve
is incorporated in the ball assembly, so that as control
fluid pressure is being supplied to open the ball valve, the
pressure differential across the ball valve is first equalized,
and then the ball valve is shifted to the open position. To
accomplish thls, the ball valve is composed of a ball ;
base and ball cap providing a by-pass passage which is opened
when the ball base is shifted relative to the cap. In
addition to the fore~oing, actuation of the ball valve :`~
,
to the closed position is assisted by a spring, so that
even in the absence o sufficient well pressure to assure
- ,.~
closure of the shutoff valve, the latter will be nevertheless ~ ;-
`~l 20 closed and the sealing efEectiveness of the valve will
be maintained. ;~
The present invention provides an improved
. .
subsurface valve of the general type and more particularly
of the split ball type as described in the above-mentioned
Patent.
:
;~ In this connec-tion, the presen-t inven-tion provides
a subsurface safety valve for wells, wherein the ball valve is
split to provide a ball base and a ball cap which co-operate to
: . ~
provide an equalizing fluid path for initially relieving the
. - , -~ ~ .
- 2 - ~ -
46~934
ball valve of differential pressure before the ball valve is
opened, wherein the ball base and the ball cap have screening
passages which are smaller than the aqualizing ~luid path so
that particles, such as sand or the like, cannot cause blockage
of the equalizing path or passage in the ball cap. A resilient
seal i9 molded into the ball base between the screen openings and
the fluid passage in the cap to provide a seal when the ball
valve is in the closed position.
The present invention also provides a valve
supporting and housing structure which is adjustable to assure
snug seating of the ball cap against its sleeve. This is
; accomplished by adjustably mounting a valve supporting sleeve
on an upper mandrel so that adjustment of the sleeve longitudinally
with respect to the mandrel adjusts the ball valve with respect
to its seat. ~ -
The adjustable sleeve, in addition, interconnects
the upper mandrel with a lower mandrel, the two mandrels having
seals engageable in the usual landing nipple, when the valve
asse~bly is lowered into place~ to form a seal at opposite sides
of the control fluid port in the landing nipple. The adjustable
sleeve is ported between the seals to allow communication between
the control fluid pressure port and the pressure chamber in the `~ ~;
valve assembl~ to which control fluid pressure is applied to open
the valve. The ported sleeve is, therefore, pressure balanced
2S and need not be thick-walled, so that maximum in-ternal space
... .. . .
is available for other components and a large central flow passage.
-~ ~ An internal spring guide is provided for the spring -
: ~ which acts to overcome the control fluid pressure when the valve
is closed, but the spring is not externally enclosed or guided. ;~
Thus~ the spring can be o~ relatively large diameter and strong -~
' , ' ''
-
i93~
so as to overcome substantial control fluid pressure, thereby
enabling the valve to be employecl at a greater depth, say well
below the mudline, in the case of an offshore well in relatively
deep water, or below the poin-t where paraffin forms in the well
pipe and might interfere with valve operation
This internal spring guide, moreover, is adjustable with
. respect to the valve body or support and has an internal diameter
- substantially corresponding with the opening in the ball valve. ~.
The guide has an end surface which can be positioned for engage-
ment by the ball base and ball cap when the ball valve is open, ~ : :
and, thus, a smooth bore through the valve assembly is provided
This invention possesses many other advantages, and has . .
other purposes which may be made more clearly apparent from a
consideration of a form in which it may be embodied One form is . .
; lS shown in the drawings accompanying and forming part of the present
- specification It will now be descri.bed in detail, for the ;
purpose of illustrating the general principles of the invention;
but it is to be understood that such detailed description is -
not to be taken in a limiting sense
Referring to the drawings: ~.
.,.. ..~. : .
Figure 1 is a diagrammatic.view illustrating an offshore
well, in which a subsurface automatic shutoff valve has been .
. installed; . ..
~` Figs 2a, 2b, 2c, 2d and 2e together constitute a longi~
tudinal quarter section showing one form of automatic shutoff ~
valve embodying the invention, with the valve.in the closed con- ~
''-:'''':.
dition, Figs. 2b through 2e, respectively, constituting successive :
downward continuations of Fig. 2a; - .
. Figs 3a and 3b together constitute a fragmentary longi- ::
~. ,
tudinal section of the portions of the valve assembly seen in
_ 4
~:, '
~4~93~ ~
Figs. 2a through 2e, showing the valve in the closed posi-tion but
pressure balanced condition with the by-pass valve open, Fig. 3b
being a downward continuation of Fig. 3a;
Figs. 4a and 4b together constitute a fragmentary
longitudinal quarter showing the valve in the open
pQsition, Fig. 4b being a downward continuation of Fig. 4a;
Fig. 5 is a fragmentary detail view, partly in
vertical section and partly in section, as taken on the line S-5
of Fig. 2c;
Fig. 6 is a view corresponding to Fig. S, but showing
the valve ro~ated to the open position;
Fig. 7 appearing on the same page as Fig. 1, is an
exploded detailed view in perspective of the ball valve;
Fig. 8 appearing on the same pages as Figs. 2d and 2e~
is a fragmentary de~ailed view in section showing the ball valve
and taken on the line 8-8 of Fig. 2c;
Fig. 9 is a horizontal section as taken on the line 9-9
of Fig. 3a; -
Fig. 10 is a horizontal sec-tion as taken on the line
10-10 of Fig. 3b;
Fig. 11 is a horizontal section as taken on the line
11-11 of Fig. 3b; and
Fig. 12 is a horizontal section as teken on the line
12-12 of Fig. Zb.
As seen in the drawings, referring first to Fig. 1,
;~ an automatic shutoff valve assembly is adapted to be installed in
~a string of ~ell production tubine T which extends downwardly
through a well casing C which is set in a well bore W, the tubing
T having a landing nipple N for receiving a ~alve assembly which
is retrievably seated therein by wireline tools, as will be later ,~
` 30 described. The tubing T and casing C extend upwardly through a ~-
; ~ 5 ~
: - :
' '',~ ,
, . . .
body of water -to a pla-tform P On the~platform is a conventional
valved tubing head H from which a flow line F extends, the flow
line being adapted to conduct well fluids to a suitably located
reservoir. A packer 10 is set in the ca~ing C and forms a seal
between -the tubing T and the casing below the seating nipple N.
The flow of fluid upwardly through the tubing T is con-
- trolled by the valve assembly V of Figs. 2a through 2e. It will
be seen that the landing nipple ~ is an elongated tubular body
20 threadedly connected at 21 to the iower end of the tubing T and
threadedly connected at 22 at its lower end to a downwardly exten-
ding tubular body or member 23, which may be several or thousands
o feet in length, and which is disposed between the landing nipple
and the packer 10. Such landing nipples typically have an internal
groove 24 between an upwardly facing seat or shoulder 25 and a
downwardly facing shoulder 26-. The valve assembly V lands upon
the shoulder 25, and latch means 27 engage the shoulder 26 to
retain the valve assembly against upward displacement.
Below the groove 24, the landing nipple body 20 has an ~
upper cylindrical sealing bore 28 a~d a downwardly spaced cylin- ~ ;
drical sealing bore 29, between which bores is an enlarged space ~
or bore 30. The nipple body 20 has a port 31 extending radially :~ :
into the enlarged bore 30 in which a connector fitting 32 connects
the control fluid tubing 33 which extends downwaFdly from the ~
pressure source ll in the tubing-casing annulus 34 to the landing `~ `
nipple N, whereby, as will be later described, when the safety
valve assembly V is seated and latched in the landing nipple N,
control fluid is applicable to the safety valve. ` ;
The valve assembly V is an elongated assembly adapted ~ -
to be run into the landing nipple N and retrieved by means of a
3~ wireline tool, as is well known. An elongated tubular valve body
- 6
33~
assembly 35 has an upper threaded neck 36 on which a tubular
body 37 is threadedly connect~d a~ 38. the body 37 being con-
nected at 39, at its upper end, to a running and retrieving
head 40 The head 40 has a neck 41 providing a downwardly facing
shoulder 42 for engagement by a wireline running tool or a wire-
line retrieving tool (not shown). The latch means 27 comprises
a plurality of collet or latch fingers 43 depending from a
supporting ring 44 which seats on a shoulder 45 of the body 37
and is retained in place by the head 40. The body 37 has elon-
gated slots 46 which enable the fingers 43 to be flexed inwardly.
At the lower ends of the latch fingers 43 are outwardly projecting
latch lugs 47 adapted to project into the groove 24 of the landing
nipple body 20 for engagement beneath the shoulder 26 for re-
,
taininq the valve assembly in the nipple body 20, with a downwardly
;15 facing shoulder 4~3 on the body 37 supporting the valve assembly
~ on the shoulder 25 of the nipple body 20. ~ retainer sleeve 49
, ~ . .
is reciprocably disposed in the body 37 and is biased upwardly
by a coiIed spring 50 disposed between a head flange 51 of the
sleeve 49 and the upper end neck 36 of the valve assembly. The
body 37 and the sleeve have openings 52 and 53, respectively, to
prevent fluid entrapment or bias. As is well known, a running
tool is engageable with the neck 41 and is operable to hold the
retainer sleeve 49 in a lower position enabling the collet fingers --
to flex inwardly as the assembly lands in the nipple body 20,
;. . I ~ ~-. ,
and when the running tool is removed, the sleeve 49 is forced
upwardly by the spring 50 to hold the fingers 43 oùtwardly, as
~` shown~in the latching position of Fig. 2a.
The valve assembly V comprises an elongated tubular body
structure including an upper tubular steel mandrel or body section
3~ 54 having the neck 36 thereon. This mandrel 54 has side sealing
- 7 -
.
~9L6~13~
ring means 55 engaged in nipple body 20, Another lower seal
mandrel or body section 56 has 1(-~wer side sealing ring means 57
engageable in khe lower sealing bore 29 of the sea-ting nipple
body 20 : :
Adjustable means, including a tubular sleeve 58, inter- .
connects the upper and lower seal mandrels 54 and S6 together.
This sleeve 58 is threadably connected at 59, as seen in Fig. 2b,
to the upper seal mandrel 54 and is threadedly connected at 60,
as seen in Fig. 2c, to the lower seal mandrel 56. The lower seal
mandrel 56 is threadedly connected at 61 to a lower valve body
; section 62 which extends downwardly to a lower threaded connection
63, as seen in Fig. 2d, with a ~urther downwardly extended inter~
nal spring seat and guide sleeve 64, about which is a coiled
spring 65.
This spring 65 seats at its lower end on a ring. 66, and .~
at its upper end the spring 65 engages a seat ring 67 slidably .:
: disposed on the spring guide sleeve 64. The lower spring
seating ring 66 abuts with a stop collar 68 which is threaded .. .
. at 69 onto the guide sleeve 64 for adjus-tment of the compressed
` 20 force of the spring 65. .~
;; At its lower end, the spring guide sleeve 64 is threaded : .
:' ~ .at 70 to receive a guide nose 71. The upper spring seating ring
.67 acts, under the pressure of spring 65, upwardly on a ball valve
supportin~g means 72, later to be described, which is connected.
at its upper end to an elongated piston sleeve 73. `
This piston sleeve 73 is reciprocably disposed about an ~.
~ nner valve seating sleeve 74, The connector sleeve 58, the ~ ~
:~ lower seal mandrel 56, and the upper seal mandrel 54 cooperate ~ .
to form a piston chamber 75 with the sleeve 74 in which the
~n upper piston end 76 oE the elongated piston sleeve 73 is disposed
- 8 - ~:
': ~ '.~'' '''.
~'''`',:"'`,''.,''"'`'..''' '" .",''' "'.~'",'' ''' ''
46934
The piston chamber 75 is defined between an upper seal ring 77
on the upper end section 78~of t]-,e seating sleeve 74, a lower
seal ring 79 carried by the piston sleeve 73, and an upper seal
ring 80 carried by the piston sleeve 73. The upper seal ring 77
engages in a sealing bore 81 of the seal mandrel 54 below the
-threaded connection 59 between the adjustabIe sleeve 58 and
.. ; the mandrel 54. The seal ring 80 is disposed between the upper
piston end 76 and a sealing bore 82 within the seating sleeve 74.
` At its lower end, the piston chamber 75 is sealed by engagement
of the seal 79 in the sealing bore 83 of the lower seal mandrel 56.
. Control fluid pressure is admitted to the piston
~ chamber 75 from the enlarged bore 30 of the seating nipple body
20, through one or more radial ports 8~ in the adjustable con-
. . . .
. nector sleeve 58. This sleeve 58 can be thin-walled to provide
~ 15 . space for the internal components and a large 1OW passage, since .
the sleeve 58 is pressure balanced between its interior and its .;
exterior between the upper connect:ion 59 with the sealing :.
mandrel 54 and its lower connection 60 with the lower sealing -
mandrel 56.
. 20 Control fluid pressure applied to the piston chamber
75 can act on the upper end 76 of the piston sleeve 73 and over~
`; . come the upward bias of the spring 65 to force the ball valve
supporting means 72 downwardly so that, as will be later des- ;:~
cribed, the valve means will be opened. The means 72 ~or suppor- ~ .-
.
.. 25 ting the ball valve B comprises a pair of. diametrically spaced
~` arms or elongated support members 85 di$posed in opposed
. relation and having transversely aligned pivot pins or lugs 86 :
on which the ball valve B is pivotally mounted. These arms 85
are disposed in elongated windows 87 in the valve body sleeve 62 ~:
. 30 and are interconnec.ted with the lower end of the piston sleeve 73
: . _ 9 _
:
3~
and the spring sea-ting ring 67.
At their lower ends, the pivot arms 85 have pins 88
received in sockets 89 in the ring 67. At their upper ends, the
pivot arms 85 have inwardly offset and upwardly extended lugs 90
received in recesses 91 in the piston sleeve 73, the lugs 90 being
held in the recesses 71 by a keeper ring 92. For assembly pur-
poses, it will be seen that the end lugs 90 of the arms enable
the arms to spread apart towards their lower ends before the lower
end pins 88 are engaged in the sockets 89 of the ring 67, thereby
enabling the pivot lugs or pins 86 to be engaged in the diametri-
cally spaced recesses 86a of the ball valve B. The retaining ring
has notches 92a adapted to register with the reces`ses 91 of the -
keeper ring during assembly, and then the keeper ring is rotated
to a position holding the lugs 90 in the piston sleeve.
The valve sealing sleeve 74 has at its lower end a
spherical valve engaging and sealing surface 9S engageable with
the spherical surface of the valve ball member B. The ball valve
B seals against the spherical end surface 95 on the sleeve 74 and ~`
a lower spherical sur~ace 96 on the upper end of the spring guide
64. It can also seal against an elastomeric sealing ring 97
supported by a carrier ring 98 secured to the body 62. The
:, ,
carrier ring 98, as best seen in Fig. 11, has a groove 99 in its
outer periphery adapted to receive roll pins 100 which extend
.
`~ through openings 101 in the body 62 and support the ring 98 and
:: :.
`~ 25 seal 97 in position Eor sealing engagement with the ball valve B
` when it is closed.
When the ball valve B is in the closed posltlon, it is
preferred that pressure across the ball valve be equalized before
the ball valve lS opened, thereby relieving the operating mecha-
~30 nism of the resistance caused by the pressure imbalance. In
-- 10 --
, , . . . ~ . . . . ` . ` .
3~9L
accordance with the present invention, equalizing or balancing
valve means are incorporated in thc ball valve structure, as best
seen in Figs 2c, 3b and ~ More particularly, the ball valve B
has a cap 102 having a cen-tral opening or port 103. The body or
base 104 of the ball valve s has a stem 105 adapted to e~tend into-
the opening 103. Molded into an annular groove 106 about the
stem 105 is a resilient seal ring 107a. The cap 102 and the base ~`~
-~ 104 have interengaged means for interlocking the cap and ball
together for rotation as a unit between the positions of Fig. 2c
and Fig. 4b, including inwardly extended portions of ribs 107 on
the cap 102, spaced apart to form a slot 108, the slot receiving ~-
a companion body portion 109 of the base 104. When the cap is off
of the ball base, as seen in Fig. 3b, fluid can flow through the
cap port 103 to equalize pressure across the ball valve and the
companion rib portions 107 and 109 retain the ball and cap engaged
for unitary rotation, but when, as seen in Fig. 2c, the cap is
seated, the by-pass port 103 is closed.
The fluid which by-passes the ball valve may contain
,
dirt and solid particles too large to pass through the port 103,
,
Such particles may tend to bloc~ the by-pass passage. Accordingly,
the ball valve includes means for screening the fluid during the
èqualization of pressure. For this purpose) the rib or body section
~ 109 of the ball base 104 has a number of spaced grooves llO-pro-
;` viding by-pass flow passages smaller in cross-sectio~ than the
~5 port 103 in the cap. When the ball valve B is closed, as seen
in Fig. 2c, it is desired that the lower sealing end ~5 of the ~ -
sealing sleeve 74 be in sealing engagement with the spherical
surface of the ball cap 102. Upward movement of the sealing
- sleeve 74 is limited by abutting engagement of the upper end
.:
: ~n section 78 with a shoulder 54a (Fig. 2b~ of the upper seal
.
. . : ,
~ ~65~,3~
mandrel 54. Initial positioning of the ball valve relative to
the end sealing sur~ace 95 of the sleeve 74 is enabled by -the
threaded connection 59 between the connector sleeve 58 and the
upper seal mandrel 54. This threaded connection can be adjusted
to shift the ball valve towards the sealing sleeve 74, and means
are provided for locking the parts in adjusted condition. For
this purpose, as shown, the seal mandrel 54 has a number of cir-
cumferentially spaced notches or grooves 54b into which a tab
54c on the upper end of the connector sleeve 58 is deformable to
interlock the parts in a selected adjusted position, with the
ball valve disposed for sealing engagement with the sealing
sleeve 74 and the resilient seal ring 97. -Downward movement of the piston 73 is effective to
actuate the ball valve from the closed position of Figs. 2a - 2e
and to the open position of Figs. 4a, 4b and 6. Initially,
ho~ever, the pressure across the closed ball valve is equalized,
as seen in Figs. 3a and 3b Such actuation of the ball valve is ~; -" `
caused by pi~ 111 and slot 112 means on the valve body and in
the ball base, respectively.
, . .
;~ 20 The relationship of the ball valve actuating pin 111
and the slot 112 is best seen in Figs. 5 and 6, it being under~
stood that the ball valve base 104 may have identical slots 112
at its opposite sides engaged by diametricalIy opposite pins 111.
More particularly, the ball valve base member 104, on each of its
.: :.:::
opposite sides, has a chordal flat surface 113 adjacent to the
-:
diametrically opposite bars or arms 85 of the ball support means
72. The slot 112 extends radially with respect to the axis of ~ `
rotation of the ball valve member 104, and in radial alignment
with the slot 112 a stop lug 114 projects outwardly from the
flat surface 113 and provides a pair of right angularly related
~ ' ,,
-~ - 12 -
~46~3~
stop surfaces 114a and ll~b. When the ball valve member is in
the position of Fig. 5, the stop surface ll~a engages the
vertical side wall 85a of the adjacent support arm 85, thereby
limiting rotation of the valve member to the position at which
the valve ls closed. The stop surface 114b on the stop lug 114 ~;
engages the bar surface 85a, as shown in Fig. 6, to limit rotation
of the valve member to the position at which the valve is open.
Such rotation between the closed and open positions is caused
by longitudinal or vertical movement of the valve member, the
two longitudinal extremes being shown in Figs, 5 and 6.
As previously indicated and as will later be more
fully described, the ball base member 104 is actuated or shifted
longitudinally by longitudinal movement of the piston 73. The
slot 112 is formed in such a manner as to cause such rotation
15 of the valve member as the latter moves vertically or longi- -
` tudinally. Thus, as seen in Figs. 5, 6 and 7, the mouth of
... ...
the slot 112 is formed in the valve base member 104 by opposed
walls which are disposed at a right angle to one a-no-ther and
designated 112a and 112b, and which, respectively, are parallel
20 to the stop suraces 114a and 114b. At the apex of the angle
defined between the walls 112a and 112b, the slot 112c opens
inwardly-and has walls 112d and 112e. The relationship between
the pin 111 and the walls 112b and 112d is such that some longi- ~
tudinal downward movement of the ball valve will occur without ` ;-
25~ rotation of the ball valve~ but when the pin 111 engages walls
112b and 112d, it will be rotated until the pin 111 clears wall
112b and stop surface 114b engages the bar wall 85a (Fig. 6).
Thereafter, downward movement of the ball valve will occur ~ ;
without rotation. Conversely, if the ball valve is in the
3~ position of Fig. 6, some longitudinal upward movement of the
~. . . . .. .. .
r~ 34
ball valve will occur before the pin 111 engages the walls 112a
and 112e Continued upward movem~nt will rotate the ball valve
until stop surface 114a engages the bar wall 85a and pin 111
clears wall 112a. Thereafter, continued upward movement of
the ball valve will occur without rotation. Such free or lost
motion connection of the ball valve and the rotating pin Ill
-~ not only relieves the connection of damaging forces when the
; ball valve is in either of its closed or opened positions, but
provides the travel required for full functioning of the valve, -
as will now be described.
The operation of the invention described above is -
as follows~
The tubing string is run into the well to the ;
desired locationJ the packer 10 sealing off the annulus between
the tubing and the casing C and the control fluid conduit is
simultaneously run into the well with the tubing T.
,
The sa~ety valve is normally closed, as seen in
Figs, 2a through 2e and in Fig. 5, when the pressure of control
fluid in the control fluid pressure chamber 75 is relieved,
and the spring 65 acts upwardly on the lower ends of the pivot
arms 85 to bias the piston 73 upwardly. The upward movement
~' of the piston 73 and arms 85, acting through the pivot pins ~6, ~ ` ;carries the ball valve upwardly so that the valve rotating pins
111 engaging the cam surface 112e rotate the ball valve to
2S the closed po~ition (Fig. 5). Inasmuch as the cam surface 112a
clears the pin 111, the ball valve is permitted to have a -~
' ~ certain amount of longitudinal overtravel so that it moves into ~ -
sealing engagement with the sealing end 9S of the sleeve 74 and
the resilient seal 97 ]ongitudinally, and without rotation.
~; 30 Upward travel of the seating or sea~ing sleeve 60 is limited
- 14 -
4L6~33~ ;
as previousl~ described.
When con-trol fluid pressure is applied to the
pressure chamber 75 through the control fluid tubing 33 from
the top of the well, a downward force is applied to the piston
73 to overcome the force of the spring 65 The piston 73 can
move downwardly relative to the sealing sleeve 74 until the
; shoulder 115 a~ the lower end of the piston sleeve 73 engages
a stop ring 116 on the sealing sleeve 74, as shown in Fig. 3b.
During this initial increment of downward movement o~ the piston
sleeve 73 and consequently the ball valve base 104, differential
fluid pressure maintains the cap 102 in sealing contact with the - --~
lower end of the sealing sleeve 74 and the resilient seal 97,
.
and prevents downward movement of the sealing sleeve 74, until
such time as the ball base has moved from the position of Fig
` 15 2c to the position more particularly illustrated in Fig 3b, at
which the port 103 through the ball cap is open and fluid
pressure is equalized across the cap, thereby enabling -the fluid
pressuxe acting downwardly on the sleeve 74 to shift the cap
into sealing engagement with the base to complete the spherical
or ball member, as shown in Fig, 2c, the valve seating sleeve 74
and the piston 73 then being moved together by the fluid
pressure in the chamber 75 to shift the ball longi-tudinally
and effect its rotation,
As the ball valve moves downwardly, the rotating
~S pins 111 will contact the slot surfaces 112d, thereby rotating
the ball valve from the closed position o~ Fig. 5 to the open
" position o~ Fig. 6, such open position also being shown in Fig.
4b, wherein the valve closing spring 65 has been compressed by
the pivot arms 85 and xing 67 and the spherical sealing surface
96 on the lower valve sealing sleeve and spring guide 64 and
~: ,
;- .
93~
the ball valve base and cap are sealingly en~aged At this
point, further downward movement o~ the ball valve is prevented,
and the sealing contact between the sealing surfaces of the
lower sealing sleeve and the upper sealing sleeve ~i-th the ball
valve is maintained by fluid pressure. The threaded connection
63 between the guide sleeve 64 and the body 62 enables adjustment
of the relationship between the lower seat surface 96 and the ball
If, for any reason, the control fluid pressure in the
pressure chamber 75 acting downwardly on the piston 73 should be
relieved, such as by reason of fracture of the control fluid
conduit 33 or the purposeful venting of the control fluid pressure
. , ,
at the platform P, the valve closing spring 65 will assist well
fluid pressure acting upwardly to overcome any residual control
fluid pressure to effect the closing operation by shifting ~ `
. I - ' ' ' ,`:~
lS the piston-sleeve 73 upwardly, thereby carrying the ball valve ``
therewith for closing actuation of the ball by the ball rotating ~;
pins 111, ;; `
By referring to Figs. 5, 6 and 12, it will be noted
that the valve body includes a bar 62a runnin~ along one side
.:
of a window 62b cut in the valve body 62, this bar being disposed
at that side of the window along which the cap 102 will move as
.
the ball member B rotates in shifting between the valve closed
condition shown in Fig. S and the open condition shown in Fig. 6.
When the ball valve is in the open condition, the bar 62a prevents
the ball cap 102 from alling out through the left side of the
window (as seen in Fig 6), since the cap 102 can move a very
slight distance only befbre it contacts the bar. Moreover, if
the cap is in its position elevated from the base 104, such as ~ ~
, ~,
disclosed in Fig. 3b, any attempt to rotate the ball member B
would result in the cap 102 engaging the bar, which would prevent
- 16 -
9~
the cap from rotating from its position engaging the sleeve 74.
The cap 102 and the ball base 104 must be together, as shown
in Fig. 5, before the ball member B can be shifted from its -
closed position illustrated in Fig. 5 -to its open position
illustrated in Fig. 6. With the cap and ball base together,
the ball member B is permitted to be rotated in a counter-
clockwise direction, as seen in Fig 5, the cap 102 clearing the ~-
bar 62a. This bar cannot interfere with the continued rotation
of the ball member B in the counterclockwise direction to the
valve opening condition illustrated in Fig. 6.
' " , ',
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