GB2094861A - Annulus safety valve and well tool system - Google Patents

Abstract

A well valve system for producing a well along a tubing string and a tubing-casing annulus (21) includes a tubing string (20) having a well packer (34) for sealing the annulus around the tubing string, tubing sleeve valves (33, 35) in the tubing above (33) and below (35) the packer (34) for controlling communication between the annulus and the tubing, a tubing safety valve (30) and a separate annulus safety valve (32) in the tubing controlling flow between the sleeve valves (33, 35) past the packer (34) along an annular flow passage independent of the tubing string bore. The tubing and annulus safety valves (30 and 32) are removeable. The sliding sleeve valves (33, 35) are opened when the annulus safety valve (32) is installed and closed when the annulus safety valve (32) is removed. The sleeve valves (33, 35) include a shutter for protecting the valve seals during opening and closing. The annulus safety valve includes a housing having fixed seals engaging the tubing wall above and below the sleeve valves, a valve tube assembly including an annular valve member in the housing, springs for closing the valve member, a hydraulic piston for opening the valve member, and annular flow passages along the housing and valve tube assembly past the valve member for conducting fluids from the lower sleeve valve (35) past the packer to the upper sleeve valve (33). The annulus safety valve is held open by control fluid pressure, closed by spring force, and may be pumped open by fluid in the annulus above the valve. The only moving seals of the annulus safety valve are protected internally. <IMAGE>

Description

SPECIFICATION Annulus safety valve and well tool system This invention relates to well tools particularly for use in oil and gas wells and more specifically relates to a well valve system for controlling fluid flow in the annulus of a well.

Oil and gas wells are generally completed with one or more strings of well casing which line the well bore and a producing tubing string supported in concentric spaced relation within the casing thereby defining a central flow passage along the tubing string and an annulus around the tubing string within the casing wall. When such a well is completed into a single producing formation it is possible to produce the well through both the tubing and the annulus. Frequently such a well is completed for production from two zones one of which is produced through the tubing string while the other is produced through the tubing-casing annulus avoiding co-mingling of the fluids from the two separate zones. In such an installation a well packer is placed around the tubing string sealing the annulus at a location between the upper and lower producing formations.For safety considerations subsurface safety valves form a part of well completion systems. A tubing safety valve controls the flow in the tubing string while an annulus safety valve controls flow in the tubing-casing annulus. Such valves are located at a sufficient depth within a well to protect the well from fluid loss and possible fire in the event of damage to the wellhead at the surface. An annulus safety valve includes apparatus which defines an annular flow passage through the bore of the well packer so that fluids may bypass the packer in the annulus around the tubing string.In the present annulus safety valve systems known to be available to the industry the packing and other valve parts included on removable portions of the annulus valve are external exposed parts which tend to be damaged during running and pulling of the valve and which may be flow cut when opening and closing the valve in the well.

Further, in existing systems the annular flow passage along the well packer is generally left open thereby exposing portions of the system when the annulus valve is not in place in the well. Also, some of the existing systems comprise a combination ball and sleeve valve which are interrelated in structure and operation.

It is a particularly important object of the present invention to provide a new and improved well valve.

It is another object of the invention to provide a new and improved well valve for controlling flow in the tubing-casing annulus of a well.

It is another object of the invention to provide a new and improved well valve system which includes separate independent tubing and annulus flow control valves.

It is another object of the invention to provide an annulus safety valve for wells which includes internal moving parts and seals which are unaffected by the running and pulling of the valve.

It is another object of the invention to provide an annulus valve for a well in which the principai seals are stationary after the valve is installed in a well.

It is another object of the invention to provide an annulus safety valve system for completing a well which includes upper and lower sleeve valve arrangements for controlling flow into the annulus flow passage of the system past the well packer wherein the sleeve valves are closed when the annulus valve is not in operating position in the well and are opened when the annulus valve is installed in the well.

It is another object of the invention to provide an annulus safety valve system for a well wherein the annulus flow passage along the well packer is closed when the safety valve is not in operating position in the well.

It is another object of the invention to provide a new and improved sliding sleeve valve for a well.

In accordance with the invention there is provided a well annulus safety valve including a longitudinally movable tubular valve member supported in concentric spaced relation within a tubular housing defining an annular flow passage along the valve member within the housing between longitudinally spaced ports in the housing, springs between the housing and valve member for biasing the valve member closed, a hydraulic piston between the valve member and the housing for biasing the valve member open responsive to hydraulic fluid pressure, spaced external annular seals along the housing for sealing between the housing and a well tubing system including a well packer, a locking mandrel connected on one end of the housing for releasably-locking the annulus valve at a landing nipple along the well tubing system, and an operating key assembly along the other end of the housing for opening and closing sleeve valves along the well tubing system during installation and retrieval of the annulus valve. Further, in accordance with the invention, the annulus safety valve is operated in combination with a well completion system including a well packer connected with the well tubing, an upper sleeve valve connected with the well tubing above the packer and a lower sleeve valve connected with the well tubing below the packer. The annulus safety valve housing and the well packer together with the upper and lower sleeve valves define an annulus flow passage along the packer for bypassing annulus fluids past the packer between the upper and lower sleeve valves.When the annulus safety valve is installed within the packer and upper and lower sleeve valves, the packing along the annulus safety valve housing remains fixed during operation of the valve member of the annulus safety valve. The upper and lower sleeve valves are opened and closed by installation and removal of the annulus safety valve so that the sleeve valves are open when the safety valve is in operating position and are closed when the annulus safety valve is removed from the tubing string system.

Also, in accordance with the invention there is provided a tubing string sliding sleeve valve having a seal protecting shutter operated by a single set of lugs.

The foregoing objects and advantages of the invention will be better understood from the following detailed description of a preferred embodiment of the invention taken in conjunction with the accompanying drawings wherein: Figures 1 A and 1 B together form a longitudinal schematic view in section of a well bore completed with the annulus safety valve and tubing completion system of the invention; Figures 2A-2H taken together form a longitudinal view in section and elevation of the annulus safety valve and the tubing string system of the invention showing the safety valve closed and the sleeve valves of the tubing string system open; and Figures 3A-3H inclusive form a longitudinal quarter section of the annulus safety valve and tubing string system of Figures 2A-2H showing the annulus safety valve open and the sliding sleeve valves of the tubing string system open.

Referring to Figures 1A--l B, a well bore 10 is drilled into an earth formation 11 to a desired depth penetrating one or more oil and/or gas producing formations. The well bore is lined with a series of casing strings including surface casing 12 installed in the well bore and cemented at 1 3 with the surrounding wall of the well bore. A second string of well casing 1 4 is suspended within the surface casing extending to a desired depth below the lower end of the surface casing in accordance with standard well completion procedures. A well-head assembly 1 5 is mounted on the upper ends of the casing strings 1 2 and 14.

The wellhead 1 5 is a suitable standard wellhead assembly including the necessary flow control valves and related structure, not shown, for controlling flow in the tubing string and in the tubing-casing annulus of the well. A tubing string assembly 20 is supported in the well bore from the wellhead spaced within the casing 14 defining with the casing an annulus 21 which extends into the well for the flow of the fluids which are controlled by the annulus safety valve of the invention. A port 22 in the wellhead leads to the annulus 21. The wellhead is further provided with a hydraulic control line 23 extending down the well bore to a tubing safety valve which may be installed in the tubing string. Similarly a hydraulic fluid control line 24 is connected through the wellhead extending down the well bore for operation of the annulus safety valve of the invention.The tubing string system 20 includes a tandem connected landing nipple 25 for a wireline removable tubing safety valve 30, a landing nipple 31 for releasable locking of an annul us safety valve 32 constructed in accordance with the invention, an upper sleeve valve 33, a packer 34 for sealing between the tubing and the casing 14, and a lower sleeve valve 35. The casing 14 may open at the lower end thereof to an upper producing formation flowing into the annulus 21, not shown, while the tubing string 20 may extend downwardly through a second packer, not shown, for communication with a lower producing formation below the second packer. The well completion apparatus connected with the lower portion of the tubing string 20 and the lower end of the casing 14 includes standard well completion components which may vary depending upon the characteristics of the particular well.The tubing string system 20 is run into the well bore through the wellhead as a single unit with the packer 34 being set at the desired depth above the upper producing formation in a well which is produced from two vertically spaced formations. The annulus safety valve of the invention is run on a wireline and set in the tubing string system after the packer is set. The tubing safety valve is then run and set in the tubing string system above the annulus safety valve by standard wireline apparatus and procedures. The well packer 34 may be a standard hydraulic set Type RH packer as manufactured and sold by Otis Engineering Corporation and illustrated and described at page 3944 of the 1 974-75 edition of The Composite Catalog of Oilfield Equipment and Services published by World Oil, Houston, Texas.The wireline retrivable tubing safety valve 30 may also be a standard safety valve such as the Otis Engineering Corporation Type DK illustrated and described at page 3998 of the 1974-75 edition of The Composite Catalog of Oilfield Equipment and Services, supra.

Referring to Figures 2A-2H, the landing nipple 31 of the tubing string system 20 has an internal annular landing and locking recess profile 40 designed for the landing and locking of the locking mandrel supporting the annulus safety valve 32 in the tubing string. Below the recess profile 40, the landing nipple 31 is provided with a control line support bracket 41 and a control line fitting 42 connected with the landing nipple communicating with a port 43 through the landing nipple for control fluid from the control line 24 for controlling the operation of the annulus safety valve 32. The landing nipple 31 has an enlarged lower end portion 44 which is threaded into the upper end of a tubular housing 45 of the upper sliding sleeve valve 33. The lower end of the sleeve valve housing 45 connects into the body of the packer 34. The lower end of the packer is connected into the housing 45 of the lower sliding sleeve valve 35 which is identical in construction to the upper sliding sleeve valve 33.

The structure and operation of the upper and lower sliding sleeve valves 33 and 35 is similar to the sliding sleeve valve disclosed and claimed in allowed United States Patent Application 053,782, filed July 2, 1979 by John V. Fredd and assigned to Otis Engineering Corporation. The sleeve valves 33 and 35 are of a special design including a tubular shutter which protects seals of the valve as the valve is opened and closed.

Referring to Figures 2B and 2C, the housing 45 of the sleeve valve has one or more side ports 50 for communication with the tubing-casing annulus. A tubular shutter 51 is mounted for longitudinal sliding movement within the housing to open and close the side ports 50 in sequential steps with the opening and closing of the valve member of the sleeve valve to protect the seals on the valve member. The shutter 51 has a reduced end portion 52 threaded into a shutter operating sleeve 53 which holds a plurality of circumferentially spaced shutter operating lugs 54 disposed in windows 55 of the shutter operating sleeve. The housing of the sleeve valve has a central bore portion 60 which is larger in diameter than a bore portion 61 to provide two radial positions for the shutter operating lugs 54.The bore portions 60 and 61 are separated by an internal annular cam shoulder 62 which causes the lugs 54 to move inwardly from the large bore portion 60 to the smaller bore portion 61 during the opening of the sleeve valve. A tubular valve member 63 having spaced external annular O-ring seals 64 and 65 is siidably positioned within the shutter 51 for opening and closing the side port of the sleeve valve in timed sequence with the operation of the shutter. The valve member 63 has a side port 70 for fluid flow when the valve member is open. The valve member 63 is threaded on an operating tube 71 which fits in telescoping sliding relation into the reduced portion 52 of the shutter. The operating tube 71 has an external annular recess 72 which operates in conjunction with the lugs 54 in opening and closing the shutter.The operating tube 71 also has an internal annular operating key profile 73 which is engageable by an operating key on the annulus safety valve 32 so that when the safety valve is installed the sliding sleeve valves 33 and 35 are opened and when the valve is retrieved the sleeve valves are closed. The key profile 73 functions during the opening of the sleeve valve.

The valve member 63 is similarly provided with an operating key profile 74 which is engaged by the operating key on the annulus safety valve for closing the sliding sleeve valve when the annulus safety valve is retrieved. The end edge 75 of the shutter fits tightly against the end edge 80 of the sliding sleeve valve housing port 50. The operating lugs 54 couple the shutter and the operating tube 71 together opening and closing the shutter in a sequence which effects the opening of the valve member 63 before the shutter opens and closes the valve member after the shutter has closed so that when the O-ring 64 moves across the gap between the end 80 of the side port and the end edge 75 of the shutter, the shutter is tightly engaged with the port surface both during opening and closing of the valve. The shutter 51 and the valve member 63 are shown in the open position in Figure 2B.When the valve member and shutter are both closed the shutter end edge 75 engages the side port window 80 and the end edge 79 of the valve member is engaged with an internal annular stop shoulder 81 within the housing of the sliding sleeve valve.

During the opening of the sliding sleeve valve the operating key on the annulus safety valve engages the key profile 73 within the operating tube 71 of the sliding sleeve valve moving the operating tube and the valve member 63 downwardly so that the O-ring 64 passes the gap between the closed shutter surface and the side port surface 80 after which the external annular operating shoulder 82 on the lower end of the valve member 63 engages the internal annular operating shoulder 83 within the shutter 51 pulling the shutter downwardly.

When the shutter is closed the operating lugs 54 are up in the enlarged bore portion 60 above the cam shoulder 62 within the sleeve valve housing.

The downward force on the shutter cams the lugs 54 into the recess 72 of the operating tube which moves into alignment with the lugs as the operating tube moves downwardly. The recess 72 allows the lugs 54 to be cammed inwardly by the shoulder 62 releasing the shutter to move downwardly. The shutter is then pulled to the open position shown in Figure 2B. When the operating tube moves to the lower end position at which the shutter and the valve member of the sliding sleeve valve are fully open, the operating key on the annulus safety valve is cammed inwardly out of the key recess 73 so that the annulus safety valve may continue downward movement after opening the upper sliding sleeve valve. The lower sliding sleeve valve is opened in the same manner.Upon return upward movement of the operating key on the annulus safety valve when the annulus safety valve is retrieved, the key engages the recess 74 at the upper end of the valve member 63 pulling the valve member upwardly along with the operating tube 71. Since the lugs 54 are at inward positions within the recess 72 of the operating tube the upward force on the operating tube lifts the lugs 54 upwardly raising the shutter 51 until the upper end edge 75 of the shutter engages the side port surface 80 which occurs before the valve member 63 moves upwardly relative to the shutter. When the lugs 54 pass above the surface 62 into the larger bore portion 60 of the sleeve valve housing, the lugs are cammed outwardly out of the recess 72 releasing the operating tube 71 and the valve member to continue upwardly for closing the valve member.The valve member and operating tube are pulled upwardly until the upper end edge 79 of the valve member engages the stop shoulder 81 within the sleeve valve housing. The operating key on the annulus safety valve is then cammed out of the profile 74 of the valve member releasing the annulus safety valve to be pulled by a wireline from the operating position in the tubing string system 20. Both the lower and upper sliding sleeve valves are closed in this same manner as the annulus safety valve is retrieved. Since the shutter opens after the valve member opens and closes before the valve member closes the O-ring 63 is not subjected to flow cutting at the side port of the sliding sleeve valve. When the lugs 54 are cammed outwardly from the recess 72 of the operating tube 71 the larger diameter of the operating tube below the recess 72 moves behind the lugs so that the lugs are locked outwardly in the larger bore portion 60 of the sleeve valve housing. Since the lugs 54 are held outwardly above the shoulder 62 the shutter 51 is locked closed so long as the operating tube is at the upper position at which the valve member 63 is closed. The sleeve valves 34 and 35 have integral locking collet fingers 76 along the recess profile 73 providing a detent to releasably lock the sleeve valves open and closed. The boss along each finger 76 engages the internal recess 77 in the housing section 46 to lock the sleeve closed and the recess 78 to lock the sleeve open, as illustrated in Figures 2C, 3C, 2G, and 3G.The upper and lower sliding sleeve valves fully close off the annul us flow passage controiled by the annulus safety valve of the invention when the valve is removed from the tubing string system and open the annulus flow passage when the annulus safety valve is installed for operation in the tubing string system.

Referring to Figures 2A-2H, the annulus safety valve 32 of the invention includes a tubular valve member assembly 90 which is slidably positioned in concentric relationship within a valve housing assembly 91. Referring to Figure 2A, a locking mandrel assembly 92 is secured on the upper end of the valve housing 91 for releasably locking the annulus safety valve in the landing nipple 31 at the landing and locking recess 40.

The locking mandrel 92 is a standard Type X locking mandrel manufactured by Otis Engineering Corporation and illustrated and described at page 3958 of the 1974-75 edition of The Composite Catalog of Oilfield Equipment Services, supra. The locking mandrel threads into the upper end of the safety valve housing and carries a packing assembly 93 which seals with the bore of the sliding sleeve valve housing 44 above the control fluid port 43.

The annulus safety valve housing 91 includes a head portion 94 which carries an internal O-ring seal 95 for sealing between the head portion and the valve member assembly 90. The head portion 94 has a reduced external annular portion 100 which with the inner wall of the head portion of the sleeve valve housing 44 defines an annular chamber 101 for control fluid introduced through the port 43 to control the operation of the annulus safety valve. A packing assembly 102 is mounted on the head portion 94 below the reduced section 100 for sealing the lower end of the control fluid annulus 101. A side port 103 admits control fluid from the annulus 101 into an enlarged bore portion 104 of the safety valve housing head portion 94 which defines a control fluid operating chamber around the valve tube assembly 90 within the safety valve housing 91.An annular operating piston 105 is positioned within the chamber 104 between the valve tube assembly 90 and the annulus safety valve housing 91. The upper end portion of the valve tube assembly 90 has an external annular operating flange 110 which is engageable by the piston 105 for opening the annulus safety valve hydraulically. The annulus safety valve housing head portion 94 has a lower tubular valve seat portion 111 provided with a lower end edge valve seat 11 2 which is in general alignment with the side port 50 in the sliding sleeve valve 33 when the annulus safety valve is installed in the tubing string system 20 supported from the landing nipple 31.An annular valve 113 having an upper valve portion 114 and a reduced lower internally threaded body portion 11 5 is secured along the body portion with a lower end portion of the upper valve tube assembly section 106. The valve member 113 has an upper end tapered valve seat surface 1 20 which seats against the seat surface 112 on the valve member 111 forming a metal-to-metal seal when the valve member is closed against the seat member as shown in Figure 2B. The upper end section 106 of the valve tube assembly 90 has an external annular boss 121 which forms a sliding fit within the valve seat member 111 performing a guiding and spacing function as the valve tube assembly moves between the valve closed position of Figure 2B and the valve open position of Figure 3B.The valve member 113 is provided with circumferentially spaced ports 1 22 located along the tapered portion of the valve member between the upper end portion 114 and the reduced lower end portion 11 5 of the member. The valve member 114 is concentrically spaced around the valve tube assembly section 106 defining an annular flow passage 123 for fluid flow along the valve assembly from the ports 122 upwardly along the valve tube section 106 to the upper end of the valve member when the valve member is open as shown in Figure 3B. The housing of the annulus safety valve has a tubular portion 124 which is threaded along the upper end portion to the lower end portion of the annulus safety valve head section 94 around the valve seat portion 111 and extending in concentric spaced relation along the valve tube assembly section 106 and the valve member 114.The housing section 124 has a side port 125 through which fluids flow to the side ports of the upper sliding sleeve valve 33 when the annulus safety valve member 114 is at the lower open position of Figure 3B. The valve member 114 fits in sliding relationship within the housing section 124 and carries an external annular seal 130 which forms a sliding seal between the valve member and the inner wall of the housing section as the valve member 114 is opened and closed. The reduced portion 11 5 of the valve member 113 forms an annular flow passage between the valve tube assembly below the ports 122 within the housing section 124 leading to the ports 1 22 from below the valve member.

The annulus safety valve 32 has a longitudinally extended housing and tubular valve member assembly which extends below the lower sleeve valve 35 below the padker 34 defining an annular flow passage through the packer from the lower sleeve valve assembly to the upper sleeve valve assembly so that the annulus fluids may flow from the tubing-casing annulus below the packer into the annulus above the packer through the annulus safety valve. The housing of the annulus safety valve includes the upper section 1 24 which is threaded along a lower end portion on the upper end of the housing section 1 32 supporting an external annular packing assembly 133.Below the packing assembly 133 the housing section 132 is reduced in diameter and provided with circumferentially spaced ports 1 34 which admit annulus fluids from below the packing 133 into an annulus 135 around the valve member tubing assembly 90 within the housing sections 124 and 1 34 leading into the annulus 131 which communicates with the valve member ports 122.

The housing section 132 has an internal annular flange 140 which carries an O-ring seal 141 forming a sliding seal between the flange and the valve tube assembly below the ports 134. The lower end portion of the housing section 1 32 is threaded on the upper end of a housing section 142 which has an internal upper end flange 143 which has an upper end edge 144 defining a spring support shoulder for one of the springs used to bias the valve member tube assembly 90 toward the closed position. A plurality of the annulus valve housing sections 142 are connected together in tandem providing sufficient length to the annulus valve housing to extend into the lower sleeve valve 35.The outside diameter of the housing sections 142 is smaller than the diameter of the tubing assembly 20 along the upper sliding sleeve valve, the packer, and the lower sliding sleeve valve defining an annular flow passage 145 for annulus fluids flow from the lower sliding sleeve valve through the packer into the side ports 134 of the annulus safety valve. The bottom annulus safety valve housing section 142 threads onto the upper end of a tubular seal section 1 50 which has an enlarged lower end portion supporting an annular packing assembly 151 for sealing within the lower portion of the bottom sliding sleeve valve defining the lower end of the annular flow passage 145.An operating key assembly 1 52 is secured by a threaded connection on the lower end of the housing seal section 1 50. The operating key assembly has an upper coupling section 1 53 connected with a key cage 1 54 having a plurality of circumferentially spaced longitudinal windows 1 55. A sleeve valve operating key 1 60 is positioned in each of the windows 1 55 for radial expansion and contraction to operate the upper and lower sliding sleeve valve assemblies 33 and 35 as the annulus safety valve is installed and retrieved. A tubular mandrel 161 is threaded along an end portion into the coupling 1 53 and extends within the key case 1 54 internal of the operating keys 1 60.A longitudinal leaf-type spring 1 62 is positioned in each of the windows 1 55 between the key 1 60 in the window and the outer surface of the mandrel 161 for biasing the key radially outwardly. The upper end of each of the springs 1 62 has a bent end portion 1 63 which fits into a hole in the upper end of the adjacent key 1 60 for loosely coupling the spring with the key to aid in alignment and positioning of the spring with respect to the key. The longitudinal side edges of the keys 1 60 and the key cage windows 1 55 are shaped to retain the keys in the windows as the keys move inwardly and outwardly along the tubing string assembly opening and c;osing the sliding sleeve valves.The outer profile along the length of each of the keys is shaped to conform to the internal operating profiles of the sleeve member 63 and the operating tube 71 of each of the sliding sleeve valve assemblies 33 and 35. The keys 1 60 are held outwardly by the springs 1 52 so that the key profiles drag along the tubing string assembly wall until the keys reach the operating profiles of the sliding sleeve valves. The keys then extend outwardly engaging the appropriate operating profile for opening and closing each of the sleeve valves as the annulus safety valve is installed and retrieved.

The operating tube assembly 90 of the annulus safety valve is connected in telescopic concentric arrangement within the safety valve housing extending into the member 1 50 at the lower end of the housing as shown in Figures 2G and 3G.

The lower end of the upper section 106 of the valve tube assembly fits into the enlarged upper end portion 1 70 of a tubular section 1 71 which is concentrically positioned within the housing sections 124 and 132. The valve.tube section 171 is spaced internally of the housing sections 1 24 and 132 defining the annular flow passages 131 and 135 along which the annulus fluids flow in the safety valve from the ports 134 to the ports 1 22 as illustrated in Figures 2B and 2C. The O-ring 141 in the internal flange 140 of the housing section 132 fits in a sliding seal relationship along the outer wall of the valve tube section 171. The lower end portion of the valve tube section 1 71 fits into the enlarged upper end 172 of a tubular spring section 1 73 of the valve tube assembly.

The lower external annular end edge of the enlarged upper end portion 1 72 of the tube section 173 provides an annular stop shoulder 174 for the upper end of a spring 1 75 confined between the shoulder 1 74 and a spring support shoulder 144 on the upper end edge of the casing section 142. The spring 1 75 fits within the annular space 180 defined between the outer surface of the tube assembly section 1 73 and the inner surface of the casing section 1 32. A plurality of valve tube sections 1 73 are connected together in end-to-end array with the lower end of each of such sections fitted into the enlarged upper end of each of the next below tube sections. Along each of the tube sections one of the springs 175 is confined as previously described between the stop shoulder 174 at the upper end of the tube section and a stop shoulder 144 on a housing section in which the tube section is slidable. The bottom valve tube section 1 73 telescopes into the upper end portion of the bottom packing mandrel section 1 50 of the annulus safety valve housing as seen in Figure 2G. The springs 1 75 each confined at an upper end between a stop shoulder on valve operating tube section and at a lower end on a stop shoulder in the safety valve housing combine to provide an upward valve closing force on the valve tube assembly 90 urging the valve seat 120 on the valve member 114 against the valve seat surface 112 on the valve seat member 111 as seen in Figure 2B.

When completing a well designed to use the annulus safety valve 32 of the invention, the tubing string 20 as illustrated in Figures 1 A and 1 B is run into the well as a unit preassembled at the surface. The upper and lower sleeve valve assemblies 33 and 35 are connected on opposite sides of the packer 34 supported from the tubing string which extends to the wellhead 1 5 at the surface. When assembling the sleeve valves before incorporating the sleeve valves into the tubing string assembly, the shutter 51 of each of the sleeve valves is adjusted by means of the operating lug sleeve 53 and the nut 56 which are threaded on the reduced portion 52 of the shutter to adjust the position of the operating lug sleeve 53 relative to the shutter end face 75.Movement of the lug sleeve 53 on the threaded portion of the shutter controls the position of the lugs 54 relative to the end face 75 so that the end face 75 may be lightly engaging the side port face 80 when the shutter is closed. The lugs 54 are expanded when the shutter is closed so that the lower outer tapered face of each of the lugs engages the tapered shoulder 62 in the sleeve valve housing portion 46.The sleeve valve assemblies 33 and 35 are connected in the tubing string assembly in a closed condition at which the shutter 51 and the sleeve valve member 63 are both at upper end positions, not illustrated, at which the side ports of the sleeve valve are closed and the operating lugs 54 are expanded against the housing shoulder 62 within the bore portion 60 of the housing member 46 so that the external annular recess 72 along the valve operator tube 71 is above the lugs 54 with the larger outer diameter of the tube 71 below the recess 72 holding the lugs outwardly in the position at which the shutter is locked closed.

In this condition of the sliding sleeve valve the upper end edge 79 of the valve member 63 engages the stop shoulder 81 within the sleeve valve housing. Both the upper and the lower sleeve valves are installed in the tubing assembly and run into the well bore in closed condition.

Standard installation procedures are used in running the tubing string assembly into the well bore.

When the tubing string assembly 20 is at the desired depth in the well bore iocating the packer 34 above the upper zone to be produced in a dual producing zone well, the packer 34 is hydraulically set. Standard setting procedures are followed which may include building up sufficient hydraulic pressure within the tubing string to a depth below the internal packer side port 1 80 so that hydraulic fluid pressure is communicated outwardly from the bore of the tubing string into the annular chamber 181 of the packer for forcing the annular piston 182 downwardly expanding the seal assembly 1 83 and driving the setting cone 1 84 of the packer downwardly behind the slips 1 85. The slips are expanded into the inner wall of the casing 14 after which the seal assembly 183 is compressed and expanded into a sealing relationship with the casing wall. After the packer is set the internal slips 190 of the packer lock the packer in the set position. Further details of the setting of the packer are described and illustrated at page 3945 of the 1974-75 edition of The Composite Catalog of Oilfield Equipment and Services, supra.

Following the running of the tubing string assembly 20 and the setting of the packer 34, the annulus safety valve 32 is installed. The safety valve is supported on a wireline running tool which engages the fishing neck 96 on the upper end of the locking mandrel 92 for supporting the annulus safety valve from the wireline running tool. Standard wireline running procedures are followed to lower the safety valve through the tubing string to the position through the sliding sleeve valve and packer illustrated in the drawings at which the locking mandrel engages and locks in the landing nipple 31 to support the safety valve in operating position in the tubing string assembly.

As the safety valve is lowered in the tubing string assembly, when the operating key assembly 1 52 on the lower end of the safety valve enters the upper sliding sleeve assembly 33 the operating keys 1 60 pass downwardly until the keys are aligned with the internal profile 73 within the lower end portion of the sleeve valve operating tube 71. The profile 73 has upwardly facing abrupt stop shoulders which are engaged by the downwardly facing stop shoulder on the keys 1 60 preventing the operating keys from moving downwardly past the profile 73.It will be recognized that when the operating key is moved downwardly and expanded into the recess profile 74 in the sleeve valve member 63, the upwardly facing shoulders of the profile 74 are sloping shoulders which cause the operating keys 1 60 to be cammed inwardly to retracted positions so that the keys would not remain engaged in the profile 74. With the abrupt shoulders, however, of the lower operating profile 73 engaging the keys 1 60 further downward movement of the lowering annulus safety valve forces the sliding sleeve valve operating tube 71 in a downward direction. First, the sleeve valve 71 with the sleeve valve member 63 is pulled downwardly with the O-ring 64 on the valve member 63 moving across the end face 75 of the shutter 51 which is engaging the side port face 80 so that the O-ring 64 is not subjected to flow when moving to the open position. After the O-ring 64 has moved into the shutter 51, the recess 72 of the valve operating tube 71 moves into alignment with the lugs 54 so that the lugs may move inwardly disengaging from the shoulder 62 thereby releasing the shutter 51 which is pulled into the open position of Figure 2B because of the coupling between the shutter operating lug sleeve 53, the lugs 54, and the operating tube 71.

When the operating tube reaches the lower end position the sloping shoulders at the lower ends of the keys 1 60 engage the sloping shoulder within the sleeve valve housing 46 below the lower end of the tube 71 camming the operating keys back inwardly disengaging the keys from the profile 73 so that the keys are released to continue downwardly through the packer bore into the lower sliding sleeve valve assembly 35. The keys 1 60 move downwardly through the lower sliding sleeve valve assembly opening the valve member and the shutter of the lower sleeve valve assembly after which the keys move to a position within the tubing string below the lower sleeve valve assembly as represented in Figure 2H.After the operating keys 1 60 have opened and passed below the lower sliding sleeve valve assembly, the locking mandrel 92 at the upper end of the annulus safety valve is aligned with the landing and locking recess 40 in the landing nipple 31.

The locking keys expand into the landing nipple recess releasably locking the safety valve at the operating position illustrated in Figures 2A-2H inclusive. In such position the sliding sleeve valves are latched open and the annulus safety valve of the invention is closed.

After the annulus safety valve 32 has been installed in the tubing string system 20, conventional wireline procedures and apparatus are again used to install the tubing safety valve 30 in the landing nipple 25 of the tubing string system above the annulus safety valve to provide safety valve means in the tubing string. Thus, the annulus safety valve of the invention will provide a safety valve function for well fluids produced through the well annulus while the tubing safety valve 30 is used for safety valve functions for well fluids produced through the tubing string. Under some circumstances a single producing formation may flow through both the annulus and the tubing string. In other circumstances the well is completed for production of two separate formations, one through the tubing string, and one through the annulus.In either circumstance the presence of the annul us safety valve of the invention and the tubing safety valve provides complete safety valve functions for both the tubing and annulus produced well fluid.

The annulus safety valve of the invention is opened for production through the annulus of the well by applying hydraulic fluid pressure through the line 24 into the wellhead, and downwardly in the well bore through the control line 24 to the side fitting 42 through which the control fluid flows to the passage 43 leading into the annular chamber 101 which communicates with the annulus safety valve piston chamber 104 above the operating piston 1 05. As the control fluid pressure is increased in the chamber 104 the annular piston 105 is forced downwardly engaging the operating flange 110 on the upper end section 106 of the annulus safety valve operating tube assembly 90.The piston 105 is pumped downwardly hydraulically moving the entire operating tube assembly 90 downwardly against the springs 1 75 which are compressed until the annulus safety valve member 114 is at the lower open position of Figure 3B at which the valve member seat surface 120 is spaced below the housing seat surface 112. At this open position of the annulus safety valve member well fluids in the well annulus below the packer seal assembly 1 83 flow inwardly through the side port 50 of the lower sliding sleeve valve assembly 35 past the open sleeve valve shutter 51 and through the port 70 in the valve member 63 into the bore through the valve member.The annulus fluids flow upwardly within the lower sliding sleeve valve into the annularflow passage 145 within the bore of the packer around the housing members 142 of the annulus safety valve. Above the packer the annulus fluids flow inwardly to the housing of the annulus safety valve through the ports 134 and upwardly along the internal annular flow passages 135 and 131 of the annulus safety valve to the ports 122 of the safety valve. From the ports 1 22 the annulus fluids flow inwardly and upwardly along the annular flow passage 123 within the valve member 114 around the operating tube upper end section 106 until the fluids reach the upper end seat 120 of the open annulus safety valve member 114 as illustrated in Figure 2B.The annulus fluids flow outwardly past the open annulus safety valve member through the safety valve member side port 125 and through the upper sliding sleeve valve assembly 33 through the ports 70 of the sleeve valve member 63, past the open shutter 51 of the sleeve valve assembly and back into the well annulus above the packer through the side ports 50 of the upper sleeve valve assembly. The annulus fluids may then flow to the surface to the wellhead through the well annulus 21 above the packer to the outlet 22 in the wellhead.

The control fluid line 24 providing pressure to the annulus safety valve for holding the valve open against the springs of the valve may be connected to any number of a variety of safety systems which respond to changing operating conditions such as loss of pressure, fire, and the like which require shutting the well down. Also physical damage to the wellhead causing loss of the control fluid pressure will effect the closure of the annulus safety valve.When the control fluid pressure to the annulus safety valve is reduced for any reason, either intentionally or in response to monitoring a safety condition, the reduced pressure in the chamber 104 holding the operating piston 105 of the annulus safety valve downwardly allows the operating piston to move upwardly so that the springs 1 75 of the annulus safety valve expand lifting the operating tube assembly 90 of the safety valve upwardly closing the valve. The valve is closed when the seat surface 120 on the upper end of the valve member 114 engages the downwardly facing seat surface 112 of the valve seat member 111 of the annulus safety valve housing. When the annulus safety valve is fully closed annulus fluids may not be produced through the valve past the packer. Thus the annulus of the valve is shut in.

In the event that well conditions develop which make it desirable to pump fluids downwardly through the well annulus the annulus safety valve of the invention may be pumped open to allow the fluids to be pumped past the packer into the well bore below the packer. With the annulus safety valve closed as represented in Figures 2A-2H, fluid is pumped under pressure downwardly in the well annulus 21 into the side ports 50 of the upper sliding sleeve valve assembly 33. The fluid passes through the open shutter and open valve member 63 of the sleeve valve to the side ports 125 of the annulus safety valve housing member 124.The pressure acts over an annular area of the annulus safety valve member 114 defined between the line of sealing of the O-ring 1 30 with the inside wall of the housing member 124 below the port 125 and the line of sealing between the valve housing seat 11 2 and the valve member seat 1 20.

The pressure over this annular area moves the valve tube assembly 90 downwardly against the springs 175 opening the valve member for fluid flow in the reverse direction downwardly along the previously described annular flow passages through the packer and the lower sliding sleeve valve assembly 35 through which the fluids flow into the well annulus below the packer. It will be recognized that as soon as the annulus safety valve opens the pumping pressure acts on the valve operator piston 1 05. Since the operator piston 105 is free floating with respect to the valve operator tube assembly upper end section 106, the operator piston 105 is simply pumped upwardly to the upper end position illustrated in Figure 2A leaving the operator tube assembly 90 free to be pumped downwardly to the open position.It will be recognized of course that the springs 175 continue to exert an upward force on the valve operating tube assembly 90 tending to close the valve. Thus during the downward pumping of the fluid the operating tube assembly will tend to move upwardly an downwardly opening and closing the valve or regulating. Of course, when the downward pumping stops the springs will fully reclose the annulus safety valve.

When removal of the annulus safety valve 32 is desired or required, the tubing safety valve 30 is first retrieved by wire-line methods. The control fluid pressure in the line 24 is reduced so that the annulus safety valve is closed by the springs 1 75.

A suitable pulling tool is then run into the tubing string assembly 20 on a wireline engaging the fishing neck 96 of the annulus safety valve 32.

Upward force on the fishing neck releases the locking mandrel 92 from the landing nipple 31.

After release of the safety valve locking mandrel the safety valve is lifted upwardly with the operating keys 160 on the lower end of the safety valve dragging along the inside wall of the tubing string until the keys are aligned with the profile 74 along the upper end portion of the valve member 63 of the lower sliding sleeve valve 35. When the operating keys 1 60 pass the profile 73 in the lower end of the operating tube 71 of the sleeve valve assembly, the keys simply expand outwardly into the profile and are immediately cammed back inwardly out of the profile due to the engagement of the upwardly facing sloping shoulders on the keys with the downwardly facing sloping shoulders along the profile 73.When the keys reach the profile 74, however, the downwardly facing abrupt shoulder along the profile engages the upwardly facing abrupt shoulder of the keys 1 60 so that the keys engage the profile 74 of the valve member 63. Continued upward force on the pulling tools lifts the valve member 63 along with the operating tube 71 which raises the lugs 54 engaging the recess 72 of the tube 71. As the lugs 54 are lifted the tube 53 connected with the shutter 51 is raised moving the shutter upwardly until the upper end surface 75 of the shutter engages the window surface 80 in the sleeve valve assembly housing. The upper end edge of the shutter is moving in advance of the O-ring 64 in the valve member 63 so that the shutter closes before the O-ring crosses over the line of sealing between the shutter and the window surface 80 of the housing of the valve assembly.When the lugs 54 pass above the shoulder 62 in the valve assembly housing, the lugs are cammed outwardly into the larger bore 60 out of the recess 72 of the tube 71 so that the tube 71 with the valve member 63 are released by the lugs to continue moving upwardly until the upper end edge 79 of the valve member 63 engages the stop shoulder 81 within the valve assembly housing. At this closed position of the valve member 63 the O-ring 64 is above the line of sealing between the shutter and the housing window surface 80 while the O-ring 65 is below such line of sealing thereby closing off the side ports of the lower sleeve valve assembly 35. When the sloping end surfaces of the keys 160 move above the shoulder 81 within the valve assembly housing, the keys 1 60 are cammed inwardly releasing the keys from the valve member 63 of the lower sleeve valve assembly 35.Continued upward force on the pulling tool lifts the annulus safety valve through the packer 34 and the upper sliding sleeve valve assembly 33 until the operating keys 1 60 on the lower end of the annulus safety engage and close the upper sliding sleeve valve assembly in the same manner as the lower sliding sleeve valve assembly was closed by the keys. After release of the keys from the upper sliding sleeve valve assembly the annulus safety valve is pulled through the tubing string assembly to the wellhead where it is removed from the well.

It will now be seen that a new and improved valve system for a well for controlling fluid flow in the annulus between the tubing string and the casing of the well has been described and illustrated. It will be further seen that a new and improved annulus safety valve for use in a well has been described and illustrated. It will be understood that the valve system includes upper and lower sliding sleeve valves for controling fluid flow from the well annulus into the well tubing string above and below a well packer and a removable annulus safety valve which in operating position defines an annular flow passage within the tubing string between the upper and lower sliding sleeve valves including an annular valve member in the annular flow passage for shutting off flow along such passage between the upper and lower sliding sleeve valves.The sliding sleeve valves include a protective shutter member which eliminates flow cutting of seals used in the valves.

The annulus safety valve includes external packing which remains fixed when the valve is in operating position in the tubing string assembly and includes internal ring seals which are protected against flow cutting as the valve is opened and closed.

The annulus safety valve is opened by hydraulic fluid pressure conducted to it through a control line from the surface and is closed by spring force.

The annulus safety valve includes a floating operating piston permitting the valve to be pumped open against the closing spring force.

Coaction between the annulus safety valve and the sliding sleeve valve assemblies in the tubing string assembly opens the sliding sleeve valves when the safety valve is installed and closes the sleeve valves when the safety valve is removed.

The sliding sleeve valves include a shutter which opens after and closes before the valve member of the sleeve valve opens and closes for protection of the valve member seals. The shutter is operated by a set of lugs which open, close and lock the shutter.

Claims (21)

1. An annulus safety valve for a well comprising a tubular housing having a control fluid side port near an upper end thereof, annular packing around said housing above and below said control fluid side port, well fluids side ports below said annular packing below said control fluid side port, a central annular packing below said well fluids side ports, annular packing around the lower end portion thereof below said lower sliding sleeve valve when said annulus valve is in said tubing string, said housing being reduced in outside diameter between said central packing on said housing and said packing along said lower end of said housing defining an annular fluid flow passage along said housing with the inner wall of said tubing string when said annulus safety valve is in operating position in said tubing string through said packer, and fluid ports in said housing below said central packing, said housing including an annular valve seat member having an annular valve seat adjacent to said well fluid ports in said housing, a longitudinally movable valve tube assembly disposed in internal concentric spaced relation within said housing defining between said housing and said tube assembly a control fluid chamber communicating with said control fluid side port in said housing and an annular well fluids flow passage communicating with said well fluids side ports in said housing and with said side ports in said housing below said central packing on said housing, an annular valve member along said valve tube assembly having a valve seat engageable with said valve seat member of said housing for closing said annulus safety valve and being movable to a position in spaced relation from said valve seat member for opening said safety valve, an annular piston between said valve tube assembly and said housing in said control fluid chamber and engageable with said valve tube assembly for opening said annulus safety valve responsive to control fluid pressure in said chamber, and spring means between said valve tube assembly and said housing for closing said safety valve when said control fluid pressure is reduced below a predetermined value.

2. An annulus safety valve in accordance with claim 1, wherein said spring means comprises a plurality of longitudinally spaced springs between said valve tube assembly and said housing biasing said valve tube assembly in a direction to close said valve member.

3. An annulus safety valve in accordance with claim 2 wherein said annular piston in said control fluid chamber is movable independently of said valve tube assembly for engaging said valve tube assembly when pumped in a direction to open said valve and moving in an opposite direction disengaged from said valve tube assembly to permit said valve tube assembly to be pumped in a valve opening direction responsive to fluid pressure applied to said side ports in said housing.

4. An annulus safety valve for a well, comprising a tubular housing, a locking mandrel connected with a first end of said tubular housing for releasably locking said safety valve in the tubing string of a well bore at a landing nipple, an external annular recess formed in said housing spaced from said first end to define a control fluid chamber around said housing when said safety valve is installed in a well tubing, means providing a control fluid port through said housing into said annular recess, first and second external annular packing around said housing on opposite sides of said annular recess, means providing a well fluid side port in said housing spaced from said second packing on said housing positioned to align with a side port in a tubing string valve communicating through said tubing string to a well annulus around said string when said annulus safety valve is installed in operating position in said tubing string, a third central external annular packing around said housing spaced from said well fluids port in said housing for sealing around said housing with a well tubing string wall, said second and third annular packing on said housing being on opposite sides of said well fluids side port in said housing, a fourth external annular packing on said housing along the second opposite end of said housing for sealing with a well tubing wall around said housing; said housing being reduced in diameter between said third central packing and said fourth packing on said housing to define with said well tubing string wall an annular flow passage along said housing within said tubing string for conducting well fluids along said annular flow passage within said tubing string through a packer connected in said tubing string when said annular safety valve is in operating position in said tubing string, means providing a port through said housing between said third central packing on said housing and said fourth packing on said housing for communicating said annular flow passage around said housing with the bore through said housing, means defining an internal annular valve seat surface in said housing adjacent to said well fluids side port in said housing, a longitudinally movable valve tube assembly supported in concentric spaced relation in said housing, a seal within said housing around said valve tube assembly at a first end of said valve tube assembly and said first end of said housing defining a first end of a control fluid annular cylinder around said valve tube assembly within said housing communicating with said control fluid port in said housing, an annular piston between said housing and said valve tube assembly in said control fluid cylinder movable relative to both said housing and said valve tube assembly having an external annular operating flange engageable by said annular piston for moving said valve tube assembly responsive to control fluid introduced into said control fluid chamber in a valve opening direction from said first end of said housing toward said second opposite end of said housing, said valve tube assembly including a tubular valve member secured within said housing along and spaced from said valve tube assembly defining an annular flow passage between said valve tube assembly and said valve member and having an annular valve seat along the first end thereof engageable with said annular valve seat in said housing and provided with port means along a second end thereof for well fluids flow between an annular flow passage within said valve member around said valve tube assembly and an annular flow passage between said housing and said valve member extending from said ports in said valve member to said ports in said housing between said third and said fourth annular packing on said housing, a seal around said valve member for sealing between said valve member and said housing between said annular seat on said valve member and said ports at said second end of said valve member, said annular seat on said valve member forming a metal-to-metal seal with said seat in said internal annular valve seat surface of said housing when said valve tube assembly with said valve member is at a closed position, a seal between said housing and said valve tube assembly positioned between said ports between said third and fourth annular packing on said housing and said second end of said housing, said housing and said valve tube assembly each having stop shoulder means between said housing and said valve tube assembly extending along said housing and said valve tube assembly between said seal between said housing and said valve tube assembly and said second end of said housing, and spring means between said housing and said valve tube assembly engageable with said stop shoulders for biasing said valve tube assembly in said housing in a direction urging said annular valve member of said valve tube assembly against said annular valve seat in said housing to a valve closed position.

5. An annular safety valve in accordance with claim 4, including an operating key assembly on said second end of said housing for engaging valve assemblies in said well tubing string to open said valve assemblies when said annular safety valve is installed in said tubing string and to close said valve assemblies when said annular safety valve is removed from said well tubing string.

6. An annular safety valve in accordance with claim 5, wherein said spring means between said housing and said valve tube assembly comprise a plurality of springs positioned in tandem relationship for biasing said valve tube assembly in a valve closed direction.

7. A sliding sleeve valve for use in a well tubing string to control flow between the bore of said tubing string and an annulus around said tubing string comprising a housing having side ports for communication with said well annulus, a shutter slidable in said housing for opening and closing said side ports, an operating tube provided with circumferentially spaced side windows connected with said shutter, radially movable operating lugs in said side windows for moving said shutter between open and closed positions and for locking said shutter closed when said lugs are expanded and for holding said shutter open when said lugs are retracted, said housing having a graduated bore including a first larger portion provided with an annular stop shoulder for said lugs when said shutter is closed and a smaller bore portion for holding said lugs inwardly when said shutter is open, said valve member being slidable within said shutter between open and closed position and having side windows alignable with said side ports in said housing when at said open position, longitudinally spaced ring seals on valve member, one of said seals moving across an end of said shutter when said shutter is closed, said spaced seals being on opposite sides of said end of said shutter when said shutter is closed, an operating tube connected with said valve member and slidable in said shutter operating tube, said valve member operating tube having an external annular recess for said lugs to permit said lugs to move radially inwardly when said recess is aligned with said lugs for release of said lugs and movement of said shutter between open and closed positions, said valve member operating tube having an annular locking surface for movement behind said lugs when said lugs are expanded to lock said shutter closed, and detent means on said valve member operating tube to releasably lock said valve member at said closed position and at said open position.

8. A sliding sleeve valve for connection in a well tubing string to control the flow from around said tubing string into the bore through said tubing string, comprising a housing connectible at opposite ends into said tubing string, a side port through said housing into the bore of said housing, an annular valve seat surface in said housing inward of said side port, a tubular valve shutter slidably mounted in said housing and having an end end edge seat surface engageable with said annular seat surface in said housing covering said side port in said housing and being movable to a valve open position at which said side port is uncovered and said seat surface on said shutter is spaced from said seat surface in said housing, a shutter operating tube slidable in said housing and connected with said shutter, said operating tube being provided with side window means, a shutter operating and control lug means disposed in said side window means of said shutter operating tube, said shutter operating tube being movable along a graduated bore of said housing said bore having a large diameter portion and a small diameter portion separated by an internal annular lug locking shoulder facing in the direction of said shutter for engagement by said lug means when said shutter is closed and said lug means are expanded in said large bore portion of said housing, said lug means being movable inwardly along said small diameter portion of said housing bore when said shutter is open, a tubular valve member positioned in concentric sliding relation within said shutter, said valve member having side port means aligned with said housing side port means when said valve member is open and misaligned from said housing side port means when said valve member is closed, said valve member having a stop shoulder engageable with a stop shoulder in said shutter for retracting said shutter to an open position after said valve member is open, external annular spaced seals on said valve member within said shutter positioned to span the line of engagement of said shutter seat surface with said housing seat surface when said valve member and said shutter are closed, said spaced seals retracting into said shutter when said valve member is open, ah operating tube connected with said valve member and disposed concentrically within said shutter and said shutter operating tube for opening and closing said valve member in a timed sequence with opening and closing said shutter, said valve operating tube having an external annular recess to receive inward portions of said shutter operating lug means when said recess is aligned with said lug means for permitting said lug means to move radially inwardly as said valve member operating tube is retrated to open said valve member and said shutter, said recess on said valve member operating tube having cam shoulders for expanding said lug means into said large bore portion of said housing against said lug means stop shoulder in said housing when said valve member operating tube is moved to close said valve member, said valve member operating tube having an external annular locking surface adjacent to said external annular recess for holding said lug means expanded when said operating tube is moved to close said valve member misaligning said external annular recess with said lug means thereby closing said shutter and said valve member and locking said shutter closed, internal operating key recesses in said valve member operating tube and in said valve member for engagement by an operating key for opening and closing said sliding sleeve valve, and detent means on said valve member operating tube engageable with locking recesses along said housing for releasably locking said valve member at closed and at open positions.

9. A sliding sleeve valve in accordance with claim 8 wherein said detent means comprises a plurality of collet fingers formed along said valve member operating tube, each of said collet fingers having an external annular locking boss for engagement with said locking recesses in said valve housing.

10. A sliding sleeve valve in accordance with claim 9, wherein said shutter operating tube is movable on said shutter for adjusting the spacing between said shutter seat surface and said housing seat surface adjacent said side port in said housing.

11. A well tool system comprising a tubing string, a well packer connected in said tubing string for sealing around said tubing string in a well bore annulus, a valve connected in said tubing string below said packer for controlling communication between the bore of said tubing string and said annulus, a valve connected in said tubing string above said packer for controlling communication between said bore of said tubing string and said annulus, an annulus safety valve in said tubing string for controlling a first annulus flow stream along said tubing string between said valves below and above said packer, and a tubing safety valve in said tubing string for controlling a second tubing string flow stream independently of said first annulus flow stream.

1 2. A well tool system in accordance with claim 11, wherein said tubing safety valve and said annulus safety valve are each removable from said tubing string.

13. A well tool system in accordance with claim 12, wherein said valves connected in said tubing string above and below said packer are adapted to open when said annulus safety valve is installed and to close when said annulus safety valve is removed.

14. A well tool system in accordance with claim 13, wherein said annulus safety valve and said tubing safety valve are each remotely controlled from the surface.

1 5. A well tool system in accordance with claim 14, wherein said annuls safety valve includes a housing and spaced packing along said housing defining an annular flow passage through said packer between said valve connected in said tubing string below said packer to said valve connected in said tubing string above said packer.

1 6. A well tool system in accordance with claim 15, wherein each of the valves connected in said tubing string above and below said packer is a sliding sleeve valve.

1 7. A well tool system in accordance with claim 1 6, wherein each of said sliding sleeve valves includes a valve member and a shutter adapted to open after said valve member opens and to close before said valve member closes to protect a seal on said valve member.

1 8. A well tool system in accordance with claim 1 7, wherein each of said sliding sleeve valves connected in said tubing string further includes a housing having side ports for communication with said well annuls, the shutter being slidable in said housing for opening and closing said side ports, an operating tube provided with circumferentially spaced side windows connected with said shutter, radially movable operating lugs in said side windows for moving said shutter between open and closed positions and for locking said shutter closed when said lugs are expanded and for holding said shutter open when said lugs are retracted, said housing having a graduated bore including a first large portion provided with an annular stop shoulder for said lugs when said shutter is closed and a smaller bore portion for holding said lugs inwardly when said shutter is open, said valve member being slidable with said shutter between open and closed position and having side windows alignable with said side ports in said housing when at said open position, longitudinally spaced ring seals on valve member, one of said seals moving across an end of said shutter when said shutter is closed, said spaced seals being on opposite sides of said end of said shutter when said shutter is closed, an operating tube connected with said valve member and slidable in said shutter operating tube, said valve member operating tube having an external annular recess for said lugs to permit said lugs to move radially inwardly when said recess is aligned with said lugs for release of said lugs and movement of said shutter between open and closed positions, said valve member operating tube having an annular locking surface for movement behind said lugs when said lugs are expanded to lock said shutter closed, and detent means on said valve member operating tube to releasably lock said valve member at said closed position and at said open position.

1 9. A well tool system in accordance with claim 18, wherein said annulus safety valve includes a tubular housing having a control fluid side port near an upper end thereof, annular packing around said housing above and below said control fluid side port, well fluids side ports below said annular packing below said control fluid side port, a central annular packing below said well fluids side ports, annular packing around the lower end portion thereof below said lower sliding sleeve valve when said annulus valve is in said tubing string, said housing being reduced in outside diameter between said central packing on said housing and said packing along said lower end of said housing defining an annular fluid flow passage along said housing with the inner wall of said tubing string when said annulus safety valve is in operating position in said tubing string through a packer, and fluid ports in said housing below said central packing, said housing including an annular valve seat member having an annular valve seat adjacent to said well fluid ports in said housing, a longitudinally movable valve tube assembly disposed in internal concentric spaced relation within said housing defining between said housing and said tube assembly a control fluid chamber communicating with said control fluid side port in said housing and an annular well fluids flow passage communicating with said well fluids side ports in said housing and with said side ports in said housing below said central packing on said housing, an annular valve member along said valve tube assembly having a valve seat engageable with said valve seat member of said housing for closing said annulus safety valve and being movable to a position in spaced relation from said valve seat member for opening said safety valve, an annular piston between said valve tube assembly and said housing in said control fluid chamber and engageable with said valve tube assembly for opening said annulus safety valve responsive to control fluid pressure in said chamber, and spring means between said valve tube assembly and said housing for closing said safety valve when said control fluid pressure is reduced below a predetermined value.

20. An annulus safety valve for a well, substantially as described with reference to, or as shown in, the drawings.

21. A well tool system, substantially as described with reference to, or as shown in, the drawings.