US3830297A

US3830297A - Sub-surface safety valve with improved balancing valve means

Info

Publication number: US3830297A
Application number: US00322075A
Authority: US
Inventors: D Cockrell
Original assignee: Baker Oil Tools Inc
Current assignee: Baker Hughes Oilfield Operations LLC
Priority date: 1973-01-08
Filing date: 1973-01-08
Publication date: 1974-08-20
Anticipated expiration: 1991-08-20
Also published as: DE2365155B2; GB1446889A; JPS49101204A; IT1008648B; FR2213407A1; JPS5442322B2; DE2365155A1; CA978850A

Abstract

A subsurface safety valve for wells, including a ball shutoff valve closed by well fluid pressure and opened by control fluid pressure supplied from the surface. The subsurface valve includes a control fluid pressure responsive bypass valve sleeve for equalizing pressure across the closed ball valve before the latter is opened to relieve the ball valve seating pressure. The ball valve is rotatable by support pins and is also slightly axially movable in its support. A spring acts upwardly on the bypass valve sleeve to overcome control fluid pressure when the ball valve is being closed.

Description

Umted States Patent [1 1 [111 3,830,297

Cockrell Aug. 20, 1974 SUB-SURFACE SAFETY VALVE WITH I 3,696,868 10/1972 Taylor 166/224 s IMP O BALANCING VALVE MEANS 3,741,249 6/1973 Leutwyler .1 1.

3,796,257 3/1974 Hudson 166/224 S [75] Inventor: Darryl W. Cockrell, Houston, Tex.

[73] Assignee: Baker Oil Tool, Inc., Los Angeles, 7 Primary Examiner-James A. Leppink Calif. I Attorney, Agent, or Firm-Bemard Kriegel [22] Filed: Jan. 8, 1973 [21] Appl. No.: 322,075 [57] ABS CT A subsurface safety valve for wells, including a ball shutoff valve closed by well fluid pressure and opened [52] US. Cl. 166/224 S, 137/460, 137/495, by control fluid pressure Supplied from the surface 137/629 251/635 The subsurface valve includes a control fluid pressure [51] Illlt. Cl E21) 12 responsive yp valve Sleeve for q i i g pressure [58] Field of Search 2 224 72; across the closed ball valve before the latter is opened 137/456 251/53 to. relieve the ball valve seating pressure. The ball valve is rotatable by support pins and is also slightly [56] References C'ted axially movable in its support. A spring acts upwardly UNITED STATES PATENTS on the bypass valve sleeve to overcome control fluid 3,065,794 11/1962 Page 166/224 5 pressure when the ball valve is being closed. 3,078,923 2/1963 Tausch 166/224 S 3,151,681 10/1964 Cochran 166/224 20 Clams 21 Drawmg Figures wifwe l I -52 -51 Lt -"-126:

PATENIEmuszmau AG 5a mi 26C PAIENIEB M62019 Jana-4d.

PAlimiuwnzomn SIEH'7W8 SUB-SURFACE SAFETY VALVE WITH IMPROVED BALANCING VALVE MEANS In the production of well fluids, such as oil and/or gas, from wells situated at remote locations, 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 resulting in contamination of the sea water and the sea shore 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 well head equipment resulting in the uncontrolled flow of the well until it can be killed.

Various valves have been heretofore developed for the purpose 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 full bore opening therethrough and thereby cause no substantial restriction to flow. However, such ball valves experience operating difficulties, particularly when they are being opened and the well fluid pressure which is holding the valve closed is substantial, causing a high friction loading between the sealing faces and the surface of the ball with which they are sealingly engaged. lndeed, the operating means for shifting the ball to an open position may'in some instances be destroyed.

In the prior application of Delbert L. Hudson, Ser. No. 236,256, filed Mar. 20, 1972, there is disclosed a subsurface shutoff or safety valve of the ball type incorporating a bypass or balancing valve which enables the pressure differential across the closed safety valve to be equalized before the safety valve is moved, by control fluid pressure, to an open position from a closed position. The balancing valve is a sleeve valve having a piston area responsive to control fluid pressure so that, as control fluid pressure is increased, the balancing valve is opened first and then the ball shutoff or safety valve is opened. Closure of such safety valves is accomplished by a spring means and well fluid pressure which, together, provide a force which overcomes residual control fluid pressure acting to hold the safety valve open. In valves of the type referred to above, the residual control fluid pressure may be sufficient to hold the balancing valve open or cause it to reopen in some cases, notwithstanding the provision of some means to reclose the balancing valve when the safety valve is open and to hold the balancing valve closed when the safety valve is being opened.

SUMMARY OF THE INVENTION The present invention involves the provision of an automatic subsurface shutoff valve of the ball type, wherein the ball is easy to manipulate between the closed and the open positions, notwithstanding high well fluid pressure tending to hold the valve closed, and

control fluid pressure chamber of the shutoff valve assembly, so that as control fluid pressure is being supplied to open the subsurface valve, the pressure differential across the shutoff valve is first equalized, and then the shutoff valve is shifted to the open position.

In addition to the foregoing, the present invention provides a subsurface shutoff valve assembly wherein actuation of the ball valve tothe closed position is assisted by a spring, so that even in the absence of sufficient well pressure to assure closure of the shutoff valve, the latter will be nevertheless closed and the sealing effectiveness of the valve will be maintained. Depending upon the anticipated subsurface well pressure and on the depth at which the subsurface shutoff valve is to be located in the production pipe string, an additional spring or additional springs are employed to supplement the spring force of the first-mentioned spring in overcoming the hydrostatic pressure of control fluid acting on the mechanism and tending to hold the shutoff valve open, but the supplemental spring means does not apply a force to the mechanism which maintains the sealing contact between the ball shifting .and sealing sleeve which is actuated by the firstmentioned spring. Thus, the valve is more smoothly and easily operable.

The subsurface valve of the invention may be incorporatedin a string of production tubing and run into the well in the tubing string, and control fluid is supplied through an auxiliary control tubing extending into the well along side the production tubing. Alternatively, if the well is to be produced through the casing above the shutoff valve, the shutoff valve assembly may be run into and latched in place in a seating nipple and may be retrieved from the seating nipple by wireline tools. In this latter case, the control tubing from an appropriate source of control fluid pressure is connected to the seating nipple.

In order to assure that the bypass valve or balancing valve is in the closed position when the shutoff or safety valve is being closed, a supplemental spring force is transmitted to the bypass valve and to the shutoff valve opening means with the bypass valve in the closed position so that residual control fluid pressure which tends to open the bypass valve cannot hold the bypass valve open. In other words, the safety valve closing force of the supplemental spring means is transmitted through the bypass valve to the control fluid to overcome the residual or hydrostatic pressure of the latter.

More particularly, the typical ball valve of the type here involved includes an outer tubular valve body in which is reciprocable an inner, shutoff valve actuating sleeve responsive to control fluid pressure to open the shutoff valve. The control fluid pressure also acts on the bypass valve to open the latter. Such control fluid pressure as remains when the safety valve is to be closed must be overcome and may be substantial when the shutoff valve is located a great distance from the well head or source of control fluid, as is the case on certain offshore platforms, due to the height of the column of control fluid.

In accordance with the present invention, the spring means which acts on the control fluid pressure responsive inner sleeve also-acts on the bypass valve to .overcome the control fluid pressure which must be overcome to both close the shutoff valve and the bypass valve. The spring force may be either transmitted to the bypass valve and to the inner sleeve jointly and directly or to the bypass valve and through the. latter to the inner sleeve, indirectly.

This invention possesses many other advantages, and has other purposes which may be made more clearly apparent from a consideration of forms in which it may be embodied. These forms are shown in the drawings accompanying and forming part of the present specification. They will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed descriptions are not to be taken in a limiting sense.

REFERRING TO THE DRAWINGS FIG. 1 is a diagrammatic view illustrating an offshore well in which a subsurface automatic shutoff valve has been installed;

FIGS. 2a, 2b, 2c, 2d, 2e, and 2f, together constitute a longitudinal quarter section showing one form of automatic shutoff valve embodying the invention, with the shutoff valve in the closed conditions, FIGS. 2b through 2f, respectively constituting successive downward continuations of FIG. 20;

FIGS. 3a, 3b, and 30, together constitute a fragmentary longitudinal quarter section corresponding to FIGS. 2a through 2f, but showing the bypass valve in the open condition, prior to opening of the shutoff valve, FIGS. 3b and 30, respectively constituting successive downward continuations of FIG. 30;

FIGS. 4a, 4b, 4c, 4d, 4e, and 4f together constitutes a longitudinal quarter section of the valve assembly seen in FIGS. la through If, showing the valve in the open position, but with the bypass valve closed, FIGS. 4b through 40 constituting successive downward continuations of FIG. 4a;

FIG. 5 is a fragmentary detail view in vertical section, with certain parts broken away, as taken on the line 5-5 of FIG. 2e, showing the shutoff valve closed;

FIG. 6 is a view corresponding to FIG. 5, but showing the valve rotated to the open position;

FIG. 7 is a detailed view in perspective of the ball valve;

FIG. 8a and 8b, together constitute a fragmentary longitudinal quarter section showing another form of the invention, with the bypass valve in the closed position, FIG. 8b constituting a downward continuation of FIG. 8.

As seen in the drawings, referring first to FIG. 1, an automatic shutoff or safety valve assembly V is installed in a string of well production tubing T which extends downwardly through a well casing C which is set in a well bore W. The tubing T and easing C extend upwardly through a body of water to a platform P. On the platform is a conventional valved tubing head H from which a flow line F extends, the flow line being adatped to conduct well fluids to a suitably located reservoir. A packer 10 is set in the casing C and forms a seal between the tubing T and the casing below the valve assembly V and the latter is adapted to remain open, as will later be described, only so long as it is supplied with suitable control fluid pressure from a pressure source 11 through a string of control fluid tubing CF which extends downwardly through the casing C from the pressure source 11 to the valve assembly V.

Referring to FIGS. 2a through 7, one form of subsurface valve assembly V is shown. In this form, the valve assembly comprises an elongated tubular outer body including an upper body section 21 which is threadedly connected at 22 to the lower end of the tubing string T above the valve assembly, the upper body section 21 being threadedly connected at its lower end to a coupling 23 which is threadedly connected to a body section 24 which extends downwardly and which is threadedly connected at 25 to an elongated, downwardly extended body section 26, the latter being threadedly connected to a coupling 26a at its lower end, to which a further downwardly extending body section 26b is connected, the latter being connected to a body section 260 which in turn is connected to a connector sub 28, which is in turn threadedly connected at 29, at its lower end, to the tubing string T extending downwardly in the well bore below the valve assembly. The body section 1 has a cylindrical section 30 disposed within a complemental bore 31 in the coupling 23, and suitable seal means 32 carried by the coupling 23, sealingly engages the portion 30, and other body seals may be provided. The intermediate body section 26b has an internal bore 35 and a downwardly facing internal shoulder 36 which is opposed by an upwardly facing shoulder 37 provided at the upper end of the lower body section 260. Interposed between the downwardly facing shoulder 36 and the upwardly facing shoulder 37 are a seal supporting 39 and a valve carrier or supporting member 40 which, as best seen in FIGS. 5 and 6, consists of circumferentially extended upper and lower end rings 41 and 42, respectively, and a pair of diametrically spaced longitudinally extending valve supporting ribs or bars 43 interconnecting the end rings 41 and 42. The bars 43 have inwardly extended opposing pins 44 each engaged in a slot 45 in the adjacent side of a ball valve member 46, whereby, as will be later more fully described, the ball valve 46 is adapted to be actuated between the open or flowing condition of FIGS. 50 and FIG. 6, and the closed or non-flowing condition of FIGS. 2e, 3e, and 5. Carried by the seal support ring 39 is an annular, elastomeric sealing ring 39a which resiliently sealingly engages the surface of ball valve 46, and the support ring 39 also carries an elastomeric seal ring 39b at its inner periphery for a purpose later to be described. The upper end surface 50 of the lower sub 28 constitutes an abutment or seal for a coiled compression spring 51 which is disposed within the body section 260. The spring 51 is a valve actuating spring and seats or abuts at its upper end with an abutment ring 52 which is disposed about a lower valve operating and sealing sleeve 53 reciprocable within a reduced bore 54 in the lower body section 260 which has longitudinally extended and circumferentially spaced channels 55 to enable the free flow of fluid, as will be later described. At its upper end, the valve operating and sealing sleeve 53 has an annular, spherical sealing surface 56 adapted for abutting and sealing engagement with a companion spherical valve surface 57 on the valve member 46.

Reciprocable within the outer body 20 above the valve member 46 are upper valve actuating and sealing sleeve means 60, which comprises a lower sleeve section 60a and an upper sleeve section 60b fitting in a bore 60c in the sleeve section 60a and engaged by a sealing ring 60d. The lower sleeve section 60a has its lower end a spherical valve engaging and sealing surface 61 engageable with the spherical surface 57 of the valve member 46. The upper valve sleeve section 60b extends upwardly in radially inwardly spaced relation within the outer body 20, and has at its upper extremity a cylindrical end section 62 extending reciprocably into a bore 63 of the outer body section 21, the latter having a side ring seal 64 slidably and sealingly engaging the cylindrical section 62 of the sleeve 60b above a radially inwardly extended cylinder head portion 65 of the body section 21. Provided on the valve sleeve 60b, below the cylinder head 65, is a radially outwardly extended piston section 66.

Carried by the sleeve 60b within the bore of the outer body 20 is a bypass valve sleeve 67, in accordance with the invention, having an annular piston section 68 disposed between the body outer section 24'and the inner sleeve section 60b. An outer seal ring 70a is engaged between the valve sleeve 67 and the outer body 24 and an internal seal 70b is engaged between the sleeve 60b and valve sleeve 67. Thus, it is now apparent that between the upper seal 64 and the lower seals 70a, 70b, there is defined a longitudinally extended annular pressure chamber 71 in which the piston 68 of the valve sleeve 67 is disposed and to which control fluid is admitted through an inlet port 72 in the outer body section 21 which opens into the pressure chamber 71 below the cylinder head 65 and to which the control fluid conduit or tubing CF is connected by a suitable fitting 73. The effective pressure responsive area of the sleeve 60b in the chamber 71 is the difference between the outside diameter of the sleeve 60b on which the valve sleeve 67 is disposed and the reduced diameter, upper end 62 of the sleeve 60b in the seal 64.

The upper sleeve section 60b and bypass valve sleeve 67 are adapted to be normally held in the position shown in FIGS. 2a through 2d by means of a coiled compression spring 74 which engages an upper thrust ring or seat 75 which is slidably disposed about the sleeve section 60b and engages with an abutment or downwardly facing shoulder 76 on the sleeve 60b and with the lower end of the bypass valve sleeve 67. At its lower end, the spring 74 seats on a suitable fixed stop ring 76a mounted in the other body section 26. This spring 74 exerts an upward bias to the sleeve 60b and the valve sleeve 67 so that the sleeve 60b is held in abutting engagement with an inner shoulder 21a in the outer body section 21 and the piston section 68 of the valve sleeve 67 is held in abutting engagement with stop shoulder 23a on the coupling 23 of the outer body 20, unless pressure in the chamber 71 overcomes the spring 74. Beneath the piston section 68, the bypass valve sleeve 67 has a suitable number of radial bypass ports 77 which in one position of the sleeve 67, as seen in FIG. 2b, are spaced above a suitable number of radial ports 78 in the sleeve 60, but in a second position, as seen in FIG. 3b, when the bypass valve sleeve 67 has been shifted downwardly, the

ports

77 and 78 are in communication. The lower, unported section 79 of the bypass valve sleeve 67 provides an inner cylindrical surface 80 engaged by upper seal ring means 81 and lower seal ring means 83 between which the ports 78 are disposed, so that, in the normal position of FIGS. 2b and 20, well fluid pressure cannot bypass the valve sleeve 67.

When the valve actuating and sealing sleeve means 60 are in the position of FIGS. 20 through 2e, relative to the body 20, the ball valve 46 is in the closed position, as seen in FIG. 5, but when the inner sleeve means 60 is shifted to the position of FIGS. 4a through 4c, which is a lower position relative to the valve body 20, the valve member 46 is in the open position, and the end sealing surface 61 of the sleeve 60 is biased into engagement with the spherical surface 57 of the valve member 46 by the pressure of control fluid in the chamber 71 acting downwardly on the sleeve 60b. This downward force is transmitted to th sleeve 60a at the shoulder 46a and from the sleeve 60a, through the valve member 46 to the lower valve operating and sealing sleeve 53 through the sealing surface 56 at the upper end of the latter and the spherical surface 57 of the valve member 46 and compresses the spring 51. Under these circumstances, the ball valve member 46 is in the open position, and the relationship of the ball valve actuating pins 44 and the slot 45, previously referred to, is best seen in FIG. 6, it being understood that the ball valve member 46 may have identical slots 45 at its opposite sides engaged by diametrically opposite pins.

More particularly, the ball valve member 46 on at least one of its sides has a chordal flat surface adjacent to the diametrically opposite bars 43 of the ball carrier 40. The slot 45 extends radially with respect to the axis of rotation to the ball valve member 46, and in radial alignment with the slot 45, a stop lug 91 projects outwardly from the flat surface 90 and provides a pair of right angularly related stop surfaces 91a and 91b. When the ball valve member 46 is in the position of FIG. 6, the stop surface 91a engages the vertical side wall 43a of the adjacent bar 43, thereby limiting rotation of the valve member 46 in the direction of the arrow to the position at which the valve is open. The stop surface 91b on the stop lug 91 engages the bar surface 43a, as shown in FIG. 5 to limit rotation of the valve member 46 to the position at which the valve is closed. Such rotation between the open and closed positions is caused by longitudinal or vertical movement of the valve member 46 within the carrier 40, the two longitudinal extremes being shown in FIGS. 5 and 6. As previously indicated, and as will later be more fully described, the ball member 46 is actuated or shifted longitudinally by longitudinal movement of the upper actuator sleeve means 60 and the lower actuator sleeve 53, as indicated by the arrows in FIGS. 5 and 6. The slot 45 is formed in such a manner as to cause such rotation of the valve member 46 as the latter moves vertically or longitudinally within the carrier 40. Thus, as seen in FIGS. 5, 6, and 7, the slot 45 is formed in the valve member 46 by opposed walls which are disposed at a right angle to one another and designated 45a and 45b and which respectively are parallel to the stop surfaces 91a and 91b. At the apex of the angle defined between the walls 450 and 45b, the slot opens radially inwardly at 450. Thus, the relationship beteeen the pin 44 and the wall 45a is such that the ball vavle 46 will be rotated from the position of FIG. 5 to the position of FIG. 6 when the valve member 46 moves downwardly relative to the pin 44, and, conversely, the flat wall 45b will engage the pin 44 and rotate the ball valve member from the position of FIG. 6 to the position of FIG. 5 upon upward movement of the valve member 46. However, it will be noted that when the valve member 46 is in the position of FIG. 5, the pin 44 clears the flat wall 451; so as to allow freedom of longitudinal movement of the ball valve 46 after the stop surface 91b engages the bar wall 43a, and correspondingly limited free downward movement of the ball valve 46 is permitted when the ball valve is open, as seen in FIG. 6, and the pin 44 clears the slot wall 45a when the stop surface 91a engages the side wall 43a of the bar 43. Such free or lost motion connection of the ball valve 46 and the rotating pin 44 relieves the connection of damaging forces when the ball valve is in either of its closed or opened positions.

The operation of the form of the invention described above is as follows:

The tubing string T with the valve assembly V installed therein is run into the well to the desired location, the packer 10 for sealing off the annulus between the tubing and the casing C and the control fluid conduit are simultaneously run into the well with the tubing T. Under normal conditions, the valve assembly V will be in the condition shown in FIGS. 2a through 2f, as it is being run into the well, wherein the actuator spring 51 biases the actuator and valve seating sleeve member 53 upwardly into engagement with the ball valve 46, so that the latter is held by the force of the spring 51 in the closed position of FIG. 5. The upper spring means 74 holds the inner sleeve means 60 in its upper position, and also holds the bypass valve sleeve 67 in its upper position. Upward movement of the upper actuator sleeve 60b is limited by engagement of the upper end of the portion 62, with the shoulder 21a, while upward movement of the inner sleeve 60a is limited by engagement of its upper castellated end 60e with a shoulder 60f on the coupling 26a. The ball valve 46 is therefore compressively engaged between the lower actuator sleeve 53 and the inner sleeve 60a under the influence of the spring 51 and the differential pressure caused by fluid in the well acting on the differential pressure responsive area of the lower actuator sleeve 53 when its sealing surface 56 is in sealing engagement with the ball valve 46.

When it is desired that the subsurface valve be opened to enable the well to be produced, control fluid pressure is introduced into the chamber 71 via the control fluid tubing CF from the source 11. Such control fluid pressure acts on the piston 68 of the bypass valve sleeve 67 to force the latter downwardly from the position of FIG. 2b to the position of FIG. 3b. The control fluid pressure acting on the piston 68 overcomes the resilient spring 74. When the bypass valve ports 77 in the

valve sleeve

67 and 78 in the actuator sleeve 60b are in registry, fluid communication is established through the longitudinal passages 55 in the lower body section 26 and around the exterior of the ball valve 46, through the open bypass valve means, and into the tubing T above the closed ball valve 46. Thus, when the fluid in the tubing T is equalized below and above the ball valve 46, shifting of the latter from the closed position to the open position is facilitated and frictional coengagement of the sealing sleeve surfaces 56 and 61 with the sealing surface 57 of the ball valve 46 is substantially reduced.

Thereupon, to open the ball valve 46, control fluid pressure in the control fluid pressure chamber 71 may be increased, to overcome friction, if necessary, so as to act upon the piston area 66 of the actuator sleeve 60b to force the latter downwardly from the position of FIGS. 3b and 30 to the position of FIGS. 4b through 4c, in turn moving the inner sleeve 60a downwardly to the position of FIG. 4e. During such downward movement, the bypass valve 67 is prevented from moving further downwardly by abutting engagement of a shoulder 68a thereon with the upwardly facing shoulder 68b in the outer body section 24. As the sleeve means 60 moves downwardly, the ball valve 46 will be moved correspondingly downwardly, and when the wall 45a of the respective slot 45 contacts the stationary actuator pin 44, the ball valve 46 will then be rotated counterclockwise until the stop surface 91a contacts the stop wall 43a of the ball valve carrier 40, at which time, as seen in FIG. 6, the flat wall 45a and the pin 44 are cleared for enabling all of the longitudinal forces to be transmitted from the actuator sleeve means 60 through the sealing surfaces 61, 57 and 56 and applied to the spring 51, without applying any of such force to the ball valve rotating pin and slot means. The well may then be produced so long as the pressure in the control fluid pressure chamber 71 causes a downward force on the sleeve means 60 which exceeds the opposing upward force caused by the combination of the spring 51 and the spring 74 and pressure acting on the lower actuating sleeve 53.

If, for whatever reason, control fluid pressure is reduced, say by reason of damage occurring to the control fluid conduit CF between the valve assembly V and the platform P, or if it is desired, for some other reason, control fluid pressure is reduced to shut the well in, then the spring 51 and well fluid pressure will act upwardly on the lower actuator sleeve 53, tending to close the ball valve. The upper spring 74 acts on the bypass valve sleeve 67 and the upper sleeve means 60 to provide an upward force opposing residual hydrostatic pressure of control fluid, so that the valve closes more easily. As the actuator sleeve 53 moves the ball valve 46 upwardly, the pins 44 will contact the respective flat walls 45b of the slots 45, to cause rotation of the valve 46 in a clockwise direction, from the position of FIG. 6 to the position of FIG. 5, until the stop surface 91b on the ball valve 46 contacts the stop surface 43a on the ball carrier 40. Therefore, the closed ball valve and the

respective actuator sleeves

53 and 60 may move upwardly until the upper end 62.0f the sleeve 60b contacts the stop 21a, and thereupon the ball valve 46 will be compressively engaged between the

actuator sleeves

53 and 60a under the influence of the spring 51 and the well fluid pressure below the valve assembly. It will be apparent from the foregoing, that the force required to automatically close the valve, to some extent depends upon the depth of the well at which the valve assembly V is located, i.e., on the hydrostatic pressure of the column of control fluid above the valve assembly. Thus, the spring 74 in the above-described embodiment may be strong enough to overcome the hydrostatic head of the control fluid, or, if necessary, a plurality of such springs may be employed.

The subsurface shutoff valve invention may also be incorporated in an assembly which is adapted to be run into the well and retrieved on a wireline tool, such an assembly being shown in FIGS. 8a through 8b.

In this embodiment, the production pipe T has a landing and seating nipple 300 threadedly connected at 301 and 302 in the pipe T. The seating nipple 300 has an inner cylindrical wall 303 and an inlet passage 304 leads into the nipple from a connector 305 to which control fluid is supplied from the control fluid conduit CF.

In this embodiment, the upper outer body section designated 313 is adapted, by an upper thread 313a to be connected to suitable wire line retrievable locks, not shown, such as are illustrated in the abovementioned pending application for patent. This body 313 has an upper outwardly projecting shoulder 314 forming a seat which receives packing means 316a, in the illustrated form of conventional chevron packing, to form a seal with the bore 303 above the inlet 304. Below the inlet 304, the body 313 has a downwardly facing shoulder 317 opposed to the upper end 318 of an upper, outer body coupling 325 to which the body 313 is threaded at 325a. Between the

shoulders

317 and 318 is another packing means 316b, in the illustrated form of chevron packing, adapted to sealingly engage in the bore 303 below the inlet 304. These

packings

316a and 316b accordingly straddle the inlet 304 when the assembly is lowered into place in the bore 303 and lands in the landing nipple 300.

The subsurface valve assembly in this form generally corresponds to the form previously described, in that a coiled compression spring 374 is operative to apply an upward force to the upper valve actuating and seating sleeve means 360, and another coil spring would be located beneath the ball valve 46 and act upwardly on the lower valve actuating and seating sleeve, as previously described, and therefore, the latter spring need not be relied upon to overcome the hydrostatic pressure in the control fluid tubing CF. For simplicity, therefore, only the upper actuator sleeve means 360 need be shown. In this embodiment, the upper and outer body coupling 325 is connected to a downwardly extending outer body section 323 which is in turn connected by a joint 322 to a further downwardly extending outer body section 321, the latter being connected, as will now be understood, to a lower body section corresponding to the previously described body section 26b, which supports the ball valve means. The inner sleeve or valve actuator means 360 has its upper end 362 axially shiftably extending into the bore 363 of the body 313 and sealingly engaged by a seal 364 to confine control pressure fluid in the chamber 371 below the'seal 364, the control pressure fluid having access to the chamber 371 through a port 372 in the body 313. The inner sleeve or assembly 360 includes a lower tubular member 360a which is threadedly connected. at 361 to a collar 360c and extends downwardly within the outer body section 321 to define an annular space 326 therebetween. Within this annular space 326, is the coiled compression spring 374, engageable with the thrust ring 375, which is engageable with the downwardly facing end of the bypass valve sleeve 367. This bypass valve sleeve 367 has a piston section 368. An internal seal 370a is carried by the outer body 323 and slidably engages the bypass valve sleeve 367 and the actuator sleeve 360a has another seal 360b engaging the bypass valve sleeve 367. Thus, it is now apparent that there is defined the longitudinally extended annular pressure chamber 371 to which control fluid is admitted through the port 372. The effective pressure responsive area of the sleeve means 360 in the chamber 371 is the difference between outside diameter of the sleeve 360a on which the valve sleeve 367 is disposed and the reduced diameter, upper end '362 of the sleeve 360b.

From the foregoing, it is now apparent that, as in the first-described embodiment, the spring 374 acts upwardly to overcome residual control fluid pressure in the conduit CF when the shutoff valve is to be closed. However, in this embodiment, the spring acts on the sleeve means 360 through the bypass valve sleeve 367, when the piston section 368 engages the downwardly facing shoulder 376 on the sleeve coupling 360e, upward movement of which is limited by engagement of the upper castellated end 360e with the lower end of the coupling 325, as seen in FIGS. 8a and 8b. lclaim:

1. In a subsurface shutoff valve for wells adapted to be supported in a well fluid production pipe: a body having a flow passage therethrough; shutoff valve means including a member shiftable between a first position closing said passage and a second position at which said passage is open; actuator means for shifting said member between said positions, including means defining a control fluid pressure chamber for moving said member to said second position and means responsive to the pressure of well fluid in the production pipe for biasing said member to said first position upon reduction in the pressure of control fluid in said chamber;

bypass valve means separate from said shutoff valve means and having a pressure responsive area exposed to the pressure of control fluid in said chamber for initially opening said by-pass valve means for equalizing the well fluid across said shutoff valve means before movement of said member from said first position toward said second position, and spring means acting on said by-pass valve means to oppose residual control fluid pressure during movement of said member to said first position.

2. In a subsurface shutoff valve as defined in claim 1, said spring means also acting on said actuator means.

3. In a subsurface shutoff valve as defined in claim 1, said valve member being a ball having said flow passage therethrough and a spherical sealing surface, said actuator means comprising actuatorsleeves movable longitudinally in said body, one of said actuator sleeves being responsive to control fluid pressure in said chamber, the other of said actuator sleeves being responsive to the pressure of well fluid, one of said actuator sleeves having a sealing surface engaged with said spherical sealing surface of said ball, and including means for rotating said ball between said first and second positions responsive to longitudinal movement of said actuator sleeves, and said spring means also acting on said actuator sleeve responsive to control fluid pressure for opposing said control fluid pressure.

4. In a subsurface shutoff valve as defined in claim 1, said valve member being a ball having said flow passage therethrough and a spherical sealing surface, said actuator means comprising actuator sleeves movable longitudinally in said body, one of said actuator sleeves being responsive to control fluid pressure in said chamber, the other of said actuator sleeves being responsive to the pressure of well fluid, one of said actuator sleeves having a sealing surface engaged with said spherical sealing surface of said ball, and including means for rotating said ball between said first and second positions responsive to longitudinal movement of said actuator sleeves, said bypass valve means actuating on said actuator sleeve responsive to control fluid pressure under the influence of said spring means for opposing said control fluid pressure.

5. In a subsurface shutoff valve as defined in claim 1, said valve member being a ball having said flow passage therethrough and a spherical sealing surface, said actuator means comprising actuator sleeves movable longitudinally in said body, one of said actuator sleeves being responsive to control fluid pressure in said chamber, the other of said actuator sleeves being responsive to the pressure of well fluid, one of said actuator sleeves having a sealing surface engaged with said spherical sealing surface of said ball, and including means for rotating said ball between said first and second positions responsive to longitudinal movement of said actuator sleeves, and means for rotating said ball including means for enabling bodily longitudinal movement of said ball with respect to said body during the final increment of movement of said ball to said first and second positions.

6. In a subsurface shutoff valve as defined in claim 1, said valve member being a ball having said flow passage therethrough and a spherical sealing surface, said actuator means comprising actuator sleeves movable longitudinally in said body, one of said actuator sleeves being responsive to control fluid pressure in said chamber, the other of said actuator sleeves being responsive to the pressure of well fluid, one of said actuator sleeves having a sealing surface engaged with said spherical sealing surface of said ball, and including means for rotating said ball between said first and second positions responsive to longitudinal movement of said actuator sleeves, and means for rotating said ball including a support for said ball, said support and said ball having cooperative pin and pin engaging surfaces for rotating said ball between said first and second positions.

7. In a subsurface shutoff valve as defined in claim 1, said valve member being a ball having said flow passage therethrough and a spherical sealing surface, said actuator means comprising actuator sleeves movable longitudinally in said body, one of said actuator sleeves being responsive to control fluid pressure in said chamber, the other of said actuator sleeves being responsive to the pressure of well fluid, one of said actuator sleeves having a sealing surface engaged with said spherical sealing surface of said ball, and including means for rotating said ball between said first and second positions responsive to longitudinal movement of said actuator sleeves, said means for rotating said ball including a support for said ball, said support and said ball having cooperative pin and pin engaging surfaces for rotating said ball between said first and second positions and for enabling bodily longitudinal movement of said ball with respect to said body during the final increment of movement of said ball to said first and second positions.

8. In a subsurface shutoff valve as defined in claim 1, said means defining a control fluid pressure chamber comprising an actuator sleeve reciprocable in said body and engaged with said member to shift the same to one of said positions, said sleeve having piston means responsive to the pressure of fluid in said chamber to shift said sleeve in one direction, and said spring means being engaged between said body and said sleeve for biasing said sleeve in the other direction.

9. In a subsurface shutoff valve as defined in claim 1, said means defining a control fluid pressure chamber comprising an actuator sleeve reciprocable in said body and engaged with said member to shift the same to one of said positions, said sleeve having piston means responsive to the pressure of fluid in said chamber to shift said sleeve in one direction, said bypass valve means including a valve sleeve shiftable on said sleeve, said sleeve having ports communicating with one another when said valve sleeve is in a lower position, and seal means separating said ports when said valve sleeve is in an upper position, and said pressure responsive area 7 comprising piston means on said valve sleeve for moving the latter to said lower position responsive to control fluid pressure in said chamber.

10. In a subsurface shutoff valve as defined in claim 1, said means defining a control fluid pressure chamber comprising an actuator sleeve reciprocable in said body and engaged with said member to shift the same to one of said positions, said sleeve having piston means responsive to the pressure of fluid in said chamber to shift said sleeve in one direction, said bypass valve means including a valve sleeve shiftable on said actuator sleeve, said sleeves having ports communicating with one another when said valve sleeve in in a lower position, and seal means separating said ports when said valve sleeve is in an upper position, and said pressure responsive area comprising piston means on said valve sleeve for moving the latter to said lower position responsive to control fluid pressure in said chamber, said spring means resiliently holding said valve sleeve in said upper position against the pressure of control fluid in said chamber acting on said piston means on said valve sleeve.

11. In a subsurface shutoff valve as defined in claim 1, said means defining a control fluid pressure chamber comprising an actuator sleeve reciprocable in said body and engaged with said member to shift the same to one of said positions, said sleeve having piston means responsive to the pressure of fluid in said chamber to shift said sleeve in one direction, said bypass valve means including a valve sleeve shiftable on said actuator sleeve, said sleeves having ports communicating with one another when said valve sleeve in in a lower position, and seal means separating said ports when said valve sleeve is in an upper position, and said pressure responsive area comprising piston means on said valve sleeve for moving the latter to said lower position responsive to control fluid pressure in said chamber, said spring means resiliently holding said valve sleeve in said upper position against the pressure of control fluid in said chamber acting on said piston means on said valve sleeve, said spring means also resiliently holding said actuator sleeve against movement in said one direction.

12. In a subsurface shutoff valve as defined in claim 1, said means defining a control fluid pressure chamber comprising an actuator sleeve reciprocable in said body and engaged with said member to shift the same to one of said positions, said sleeve having piston means responsive to the pressure of fluid in said chamber to shift said sleeve in one direction, said bypass valve means including a valve sleeve shiftable on said sleeve, said sleeves having ports communicating with one another when said valve sleeve is in a lower position, and seal means separating said ports when said valve sleeve is in an upper position, and said pressure responsive area comprising piston means on said valve sleeve is moving the latter to said lower position responsive to control fluid pressure in said chamber, said spring means resiliently holding said valve sleeve in said upper position until overcome by the pressure of control fluid in said chamber acting on said piston means, and coengageable portions on said body and said valve sleeve for limiting downward movement of said valve sleeve beyond said lower position, said actuator sleeve being further downwardly movable to move said member to its second position and to relocate said valve sleeve in its upper position with respect to said actuator sleeve.

13. In a subsurface shutoff valve as defined in claim 1, said valve member being a ball having said flow passage therethrough and a spherical sealing surface, said actuator means comprising an upper actuator sleeve reciprocable in said body above said ball and having a lower end sealing surface engaging said sealing surface of said actuator sleeves correspondingly upwardly and downwardly.

14. In a subsurface shutoff valve assembly as defined in claim 13, said means for biasing said lower actuator sleeve upwardly including a spring.

15. In a subsurface shutoff valve assembly as defined in claim 13, said means for biasing said lower actuator sleeve upwardly including a spring, and a well fluid responsive piston area on said lower actuator sleeve.

16. In a subsurface shutoff valve assembly as defined in claim 13, said means for biasing said lower actuator sleeve upwardly including a spring, and said spring means acting on said bypass valve means also acting on said upper actuator sleeve to bias the latter upwardly.

17. In a subsurface shutoff valve assembly as defined in claim 1, said body having means for threadedly connecting it in said well fluid production pipe.

18. In a subsurface shutoff valve as defined in claim 1, said body having external cylindrical packing means in axially spaced relation and an inlet for said control fluid pressure chamber between said packing means, said packing means being engageable in sealing position in a seating nipple in said well fluid production pipe.

19. In a subsurface shutoff valve for wells adapted to ne supported in a well fluid production pipe: a body having a flow passage therethrough; shutoff valve means including a member shiftable between a first position closing said passage and a second position at which said passage is open; actuator means for shifting said member between said positions, including means defining a control fluid pressure chamber for moving said member to said second position and means responsive to the pressure of well fluid in the production pipe for biasing said member to said first position upon reduction in the pressure of control fluid in said chamber; bypass valve means separate from said shutoff valve means exposed to the pressure of control fluid in said pressure chamber and having means responsive to control fluid pressure for opening said bypass valve means to equalize the pressure across said shutoff valve means before said actuator means moves said shutoff valve means to said second position, and spring means acting on said bypass valve means to oppose control fluid pressure actuation of said bypass valve means.

20. In a subsurface shutoff valve for wells as defined in claim 19, means for closing said bypass valve means upon movement of said shutoff valve means to said first position.

E33 3? UIQLTED STA'LES PA'lEN' l OIEFICE CER'RIFICATE OF CQRRECTIQN Patent No. 3,830,297 .vatea Auggst 20. 1974 lnventofls) DARfiYL w. COCKRELL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby cerreeted as ghown below:

Column 3, line 29: change "constitutes" to --con stitute--. line 46: chang "8" to -'-'-8a-- j Column .line 15: change "l'K to- --21- 7 line 24; after "-s1 4pporti-ng' insert "ring".

Column 10,1111? 56'z" "cfia nge "'actuating' t0 'acting- Column 1 2,- ].ine 57:"' change "is" to --L=.or-.-.-

Column 14, lih 9: ehange "ne" to --b e-..'

Signed and sealed this 10th dayof December 1974.

n v I (SEAL) Attest:

. McCOY M. GIBSON- JR. c:. MARSHALL 1mm:

Attesting Officer v Commissioner of Patents

Claims

1. In a subsurface shutoff valve for wells adapted to be supported in a well fluid production pipe: a body having a flow passage therethrough; shutoff valve means including a member shiftable between a first position closing said passage and a second position at which said passage is open; actuator means for shifting said member between said positions, including means defining a control fluid pressure chamber for moving said member to said second position and means responsive to the pressure of well fluid in the production pipe for biasing said member to said first position upon reduction in the pressure of control fluid in said chamber; bypass valve means separate from said shutoff valve means and having a pressure responsive area exposed to the pressure of control fluid in said chamber for initially opening said by-pass valve means for equalizing the well fluid across said shutoff valve means before movement of said member from said first position toward said second position, and spring means acting on said by-pass valve means to oppose residual control fluid pressure during movement of said member to said first position.

3. In a subsurface shutoff valve as defined in claim 1, said valve member being a ball having said flow passage therethrough and a spherical sealing surface, said actuator means comprising actuator sleeves movable longitudinally in said body, one of said actuator sleeves being responsive to control fluid pressure in said chamber, the other of said actuator sleeves being responsive to the pressure of well fluid, one of said actuator sleeves having a sealing surface engaged with said spherical sealing surface of said ball, and including means for rotating said ball between said first and second positions responsive to longitudinal movement of said actuator sleeves, and said spring means also acting on said actuator sleeve responsive to control fluid pressure for opposing said control fluid pressure.

9. In a subsurface shutoff valve as defined in claim 1, said means defining a control fluid pressUre chamber comprising an actuator sleeve reciprocable in said body and engaged with said member to shift the same to one of said positions, said sleeve having piston means responsive to the pressure of fluid in said chamber to shift said sleeve in one direction, said bypass valve means including a valve sleeve shiftable on said sleeve, said sleeve having ports communicating with one another when said valve sleeve is in a lower position, and seal means separating said ports when said valve sleeve is in an upper position, and said pressure responsive area comprising piston means on said valve sleeve for moving the latter to said lower position responsive to control fluid pressure in said chamber.

12. In a subsurface shutoff valve as defined in claim 1, said means defining a control fluid pressure chamber comprising an actuator sleeve reciprocable in said body and engaged with said member to shift the same to one of said positions, said sleeve having piston means responsive to the pressure of fluid in said chamber to shift said sleeve in one direction, said bypass valve means including a valve sleeve shiftable on said sleeve, said sleeves having ports communicating with one another when said valve sleeve is in a lower position, and seal means separating said ports when said valve sleeve is in an upper position, and said pressure responsive area comprising piston means on said valve sleeve is moving the latter to said lower position responsive to control fluid pressure in said chamber, said spring means resiliently holding said valve sleeve in said upper position until overcome by the pressure of control fluid in said chamber acting on said piston means, and co-engageable portions on said body and said valve sleeve for limiting downward movement of said valve sleeve beyond said lower position, said actuator sleeve being further downwardly movable to move said member to its second position and to relocate said valve sleevE in its upper position with respect to said actuator sleeve.

13. In a subsurface shutoff valve as defined in claim 1, said valve member being a ball having said flow passage therethrough and a spherical sealing surface, said actuator means comprising an upper actuator sleeve reciprocable in said body above said ball and having a lower end sealing surface engaging said sealing surface on said ball, said actuator sleeve having a piston area exposed to the pressure of control fluid in said chamber to move said actuator sleeve downwardly, a lower actuator sleeve reciprocable in said body below said ball, means for biasing said lower actuator sleeve upwardly, and means for rotating said ball between said first and second positions responsive to longitudinal movement of said actuator sleeves correspondingly upwardly and downwardly.