Shut-in tools

Claim 2

A downhole shut-in valve apparatus for shutting in a tubing string of a well, comprising: a housing having a housing bore and having a flow port means defined through said housing for communicating said housing bore with an interior of said tubing string to allow fluid flow into said flow port means and up through said housing bore, said housing having a low pressure zone defined therein; a shut-in valve element disposed in said housing bore and movable between an open position wherein said flow port means is open and a closed position wherein said flow port means is closed; a differential pressure actuating piston having first and second sides, said piston being operably associated with said shut-in valve element to move said shut-in valve element between its open and closed positions in response to movement of said actuating piston; and pilot valve means, for communicating said actuating piston with said interior of said tubing string so that a pressure differential between said interior of said tubing string and said low pressure zone moves said actuating piston and thus moves said shut-in valve element to its said closed position.

Claim 3

The apparatus of claim 1, further comprising: drive and control means for opening said pilot valve in response to a command signal.

Claim 4

The apparatus of claim 2, wherein: said drive and control means includes timer means for providing said command signal after a time delay.

Claim 5

The apparatus of claim 2, wherein: said drive and control means includes electric motor means operably associated with said pilot valve means for opening said pilot valve means.

Claim 6

The apparatus of claim 4, wherein: said drive and control means further includes a lead screw which operably connects said electric motor means and said pilot valve means.

Claim 7

The apparatus of claim 1, wherein: said first side of said actuating piston is permanently communicated with said low pressure zone; and said pilot valve means is a means for communicating said second side of said actuating piston with said interior of said tubing string.

Claim 8

The apparatus of claim 1, wherein said tubing string is a production tubing string of a completed and producing well.

Claim 9

The apparatus of claim 1, said apparatus being a multiple shut-in valve apparatus for repeatedly shutting in said tubing string of said well to perform multiple build-up and draw-down tests on said well, wherein: said pilot valve means is a means for selectively communicating one of said first and second sides of said actuating piston with said interior of said tubing string, and for simultaneously communicating the other of said first and second sides of said actuating piston with said low pressure zone, so that said pressure differential between said interior of said tubing string and said low pressure zone moves said actuating piston and thus moves said shut-in valve element between its open and closed positions.

Claim 10

The apparatus of claim 4, wherein said housing further comprises: a high pressure zone defined in said housing; a high pressure port means for communicating said high pressure zone with said interior of said tubing string; a first passage defined in said housing and communicating said first side of said actuating piston with said pilot valve means; a second passage defined in said housing and communicating said second side of said actuating piston with said pilot valve means; a third passage defined in said housing and communicating said pilot valve means with said high pressure zone; and a fourth passage defined in said housing and communicating said pilot valve means with said low pressure zone.

Claim 11

The apparatus of claim 9, wherein: said housing has a spool valve bore defined therein, each of said first, second, third and fourth passages communicating with said spool valve bore; and said pilot valve means includes a spool valve element slidably received in said spool valve bore.

Claim 12

The apparatus of claim 10, wherein: said spool valve bore and spool valve element are so arranged and constructed that when said spool valve element is in a first position relative to said spool valve bore, said first and third passages are communicated with each other and said second and fourth passages are communicated with each other so that said shut-in valve element is moved to its open position, and when said spool valve element is in a second position relative to said valve bore, said first and fourth passages are communicated with each other and said second and third passages are communicated with each other so that said shut-in valve element is moved to its closed position.

Claim 13

The apparatus of claim 9, further comprising: an actuating shaft connecting said actuating piston and said shut-in valve element; and wherein a portion of each of said first and second passages is defined through said actuating shaft.

Claim 14

The apparatus of claim 8, wherein: said housing has a high pressure zone defined therein and has a high pressure port for communicating said high pressure zone with said interior of said tubing string; and further comprising a floating piston means disposed in said high pressure zone for isolating a clean hydraulic fluid in said high pressure zone from well fluid in said interior of said tubing string.

Claim 15

A downhole multiple shut-in valve apparatus for repeatedly shutting in a production tubing string of a completed producing well to perform multiple buildup and drawdown tests on said well, comprising: a housing having a housing bore and having a flow port means defined laterally through said housing for communicating said housing bore with an interior of said production tubing string to allow fluid flow into said flow port means and up through said housing bore and then up through said interior of said production tubing string, said housing having a high pressure zone and a low pressure zone defined therein; a setting means attached to said housing for setting said housing in said interior of said production tubing string; a shut-in valve element disposed in said housing bore and movable between an open position wherein said flow port means is open and a closed position wherein said flow port means is closed; a differential pressure actuating piston having first and second sides, said piston being operably associated with said shut-in valve element to move said shut-in valve element between its open and closed positions in response to movement of said actuating piston; and pilot valve means, for selectively communicating one of said first and second sides of said actuating piston with said high pressure zone, and for simultaneously communicating the other of said first and second sides of said actuating piston with said low pressure zone, so that a pressure differential between said high pressure zone and said low pressure zone moves said actuating piston and thus moves said shut-in valve element between its open and closed positions.

Claim 16

A downhole multiple shut-in valve apparatus for repeatedly shutting in a production tubing string of a completed producing well to perform multiple buildup and drawdown tests on said well, comprising: a housing having a housing bore and having a flow port means defined laterally through said housing for communicating said housing bore with an interior of said production tubing string to allow fluid flow into said flow port means and up through said housing bore and then up through said interior of said production tubing string, said housing having a high pressure zone and a low pressure zone defined therein; a setting means attached to said housing for setting said housing in said interior of said production tubing string; a shut-in valve element disposed in said housing bore and movable between an open position wherein said flow port means is open and a closed position wherein said flow port means is closed; a differential pressure actuating piston having first and second sides, said piston being operably associated with said shut-in valve element to move said shut-in valve element between its open and closed positions in response to movement of said actuating piston; and pilot valve means, for selectively communicating one of said first and second sides of said actuating piston with said high pressure zone, and for simultaneously communicating the other of said first and second sides of said actuating piston with said low pressure zone, so that a pressure differential between said high pressure zone and said low pressure zone moves said actuating piston and thus moves said shut-in valve element between its open and closed positions.

Claim 17

The apparatus of claim 14, wherein said housing further comprises: a first passage defined in said housing and communicating said first side of said actuating piston with said pilot valve means; a second passage defined in said housing and communicating said second side of said actuating piston with said pilot valve means; a third passage defined in said housing and communicating said pilot valve means with said high pressure zone; and a fourth passage defined in said housing and communicating said pilot valve means with said low pressure zone.

Claim 18

The apparatus of claim 15, wherein: said housing has a spool valve bore defined therein, each of said first, second, third and fourth passages communicating with said spool valve bore; and said pilot valve means includes a spool valve element slidably received in said spool valve bore.

Claim 19

The apparatus of claim 16, wherein: said spool valve bore and said spool valve element are so arranged and constructed that when said spool valve element is in a first position relative to said spool valve bore, said first and third passages are communicated with each other and said second and fourth passages are communicated with each other so that said shut-in valve element is moved to its open position, and when said spool valve element is in a second position relative to said valve bore, said first and fourth passages are communicated with each other and said second and third passages are communicated with each other so that said shut-in valve element is moved to its closed position.

Claim 20

The apparatus of claim 15, further comprising: an actuating shaft connecting said actuating piston and said shut-in valve element; wherein a portion of each of said first and second passages is defined through said actuating shaft.

Claim 21

The apparatus of claim 14, wherein: said housing has a high pressure port means defined therein for communicating said high pressure zone with said interior of said production tubing string; and further comprising a floating piston means disposed in said high pressure zone for isolating a clean hydraulic fluid in said high pressure zone from well fluid in said interior of said production tubing string.

Claim 22

The apparatus of claim 14, further comprising: a floating piston disposed in said high pressure zone and-separating said high pressure zone into first and second portions; said first portion of said high pressure zone being filled with compressed gas; said second portion of said high pressure zone being filled with hydraulic fluid and being in fluid flow communication with said pilot valve means.

Claim 23

The apparatus of claim 14, said production tubing string having a landing nipple therein, wherein: said setting means is a lock mandrel constructed to be landed in said landing nipple

Claim 24

An automatically controlled downhole shut-in valve apparatus for conducting multiple drawdown and buildup testing of a completed producing well having therein a production tubing string through which well fluids are produced from a subsurface formation intersected by said well, comprising: a housing having a flow passage defined therethrough and having a flow port means defined in said housing for communicating said flow passage with an interior of said production tubing string; a shut-in valve element disposed in said housing and movable between an open position wherein said flow passage is open and a closed position wherein said flow passage is closed; setting means, connected to said housing, for setting said shut-in valve apparatus in place at a downhole location within said production tubing string and sealing said shut-in tool apparatus against an inner bore of said production tubing string at said downhole location so that fluid flow up through said production tubing string past said downhole location must flow through said flow passage of said housing; control system means for generating opening and closing command signals; and operator means for repeatedly opening and closing said shut-in valve element in response to said opening and closing command signals to perform multiple drawdown and buildup tests on said well.

Claim 25

An automatically controlled downhole shut-in valve apparatus for conducting multiple drawdown and buildup testing of a completed producing well having therein a production tubing string through which well fluids are produced from a subsurface formation intersected by said well, comprising: a housing having a flow passage defined therethrough and having a flow port means defined in said housing for communicating said flow passage with an interior of said production tubing string; a shut-in valve element disposed in said housing and movable between an open position wherein said flow passage is open and a closed position wherein said flow passage is closed; setting means, connected to said housing, for setting said shut-in valve apparatus in place at a downhole location within said production tubing string and sealing said shut-in tool apparatus against an inner bore of said production tubing string at said downhole location so that fluid flow up through said production tubing string past said downhole location must flow through said flow passage of said housing; control system means for generating opening and closing command signals; and operator means for repeatedly opening and closing said shut-in valve element in response to said opening and closing command signals to perform multiple drawdown and buildup tests on said well.

Claim 26

The apparatus of claim 2, said production tubing string including a landing nipple at said downhole location, wherein said setting means is a lock mandrel constructed to be landed in said landing nipple.

Claim 27

The apparatus of claim 22, wherein said control system means comprises: a processor means programmed to generate a series of alternating opening and closing commands at programmed time intervals.

Claim 28

The apparatus of claim 22, wherein said control system means includes and is responsive to means for sensing when a parameter at a downhole location has reached a stabilized level at which there is no further significant change in said parameter within a predetermined time period.

Claim 29

An automatically controlled downhole multiple shut-in valve apparatus for conducting efficient drawdown and buildup testing of a completed producing well having therein a production tubing string through which well fluids are produced from a subsurface formation intersected by said well, comprising: a housing having a flow passage defined therethrough and having a flow port means defined in said housing for communicating said flow passage with an interior of said production tubing string; a shut-in valve element disposed in said housing and movable between an open position wherein said flow passage is open and a closed position wherein said flow passage is closed; setting means, connected to said housing, for setting said shut-in valve apparatus in place at a downhole location within said production tubing string and sealing said shut-in tool apparatus against an inner bore of said production tubing string at said downhole location so that fluid flow up through said production tubing string past said downhole location must flow through said flow passage of said housing; monitoring means, disposed in said housing, for monitoring a downhole parameter and generating an input signal representative of said downhole parameter; receiving and generating means for receiving said input signal and for generating a command signal when said input signal meets a predetermined drawdown and buildup criterion; and control means, disposed in said housing, for moving said shut-in valve element between its said open and closed position in response to said command signal.

Claim 30

An automatically controlled downhole multiple shut-in valve apparatus for conducting efficient drawdown and buildup testing of a completed producing well having therein a production tubing string through which well fluids are produced from a subsurface formation intersected by said well, comprising: a housing having a flow passage defined therethrough and having a flow port means defined in said housing for communicating said flow passage with an interior of said production tubing string; a shut-in valve element disposed in said housing and movable between an open position wherein said flow passage is open and a closed position wherein said flow passage is closed; setting means, connected to said housing, for setting said shut-in valve apparatus in place at a downhole location within said production tubing string and sealing said shut-in tool apparatus against an inner bore of said production tubing string at said downhole location so that fluid flow up through said production tubing string past said downhole location must flow through said flow passage of said housing; monitoring means, disposed in said housing, for monitoring a downhole parameter and generating an input signal representative of said downhole parameter; receiving and generating means for receiving said input signal and for generating a command signal when said input signal meets a predetermined drawdown and buildup criterion; and control means, disposed in said housing, for moving said shut-in valve element between its said open and closed position in response to said command signal.

Claim 31

The apparatus of claim 26, wherein: said receiving and generating means includes processor means, having a programmed criterion stored therein defining said predetermined criterion, for receiving said input signal and for generating said command signal when said input signal meets said programmed criterion.

Claim 32

The apparatus of claim 27, wherein: said programmed criterion of said processor means is a stabilized level at which there is no further significant change in said parameter.

Claim 33

The apparatus of claim 27, wherein said processor means comprises a means for automatically opening said shut-in valve element and starting a drawdown test when shut-in downhole pressure has substantially peaked and for thereby minimizing a time period over which said well is shut in.

Claim 34

The apparatus of claim 29, wherein said processor means comprises a means for automatically reclosing said shut-in valve element when flowing downhole pressure has substantially bottomed out and for thereby minimizing a cycle time between successive buildup tests.

Claim 35

The apparatus of claim 27, wherein said processor means further comprises recorder means for recording data representative of said downhole parameter.

Claim 36

The apparatus of claim 27, said production tubing string including a landing nipple at said downhole location, wherein: said setting means is a lock mandrel constructed to be landed in said landing nipple.

Claim 37

The apparatus of claim 27, wherein: said processor means has a programmed sampling criterion stored therein, said processor means including means for generating a sampler command signal when said input signal meets said programmed sampling criterion; and said apparatus further comprises a sampling tool connected to said housing and including sampler control means for automatically trapping a well fluid sample in said sampling tool in response to said sampler command signal.

Claim 38

The apparatus of claim 26, wherein: said receiving and generating means includes means for comparing a first said input signal to a second said input signal and for determining when said first and second input signals are within a predetermined range of each other.

Claim 39

The apparatus of claim 34, wherein: said receiving and generating means generates said command signal in response to said comparing and determining means.

Claim 40

The apparatus of claim 35, wherein: said receiving and generating means generates a sampler command signal in response to said comparing and determining means; and said apparatus further comprises a sampling tool connected to said housing and including sampler control means for automatically trapping a well fluid sample in said sampling tool in response to said sampler command signal.

Claim 41

The apparatus of claim 26, wherein: said receiving and generating means includes mean-for making determinations of when different current values of said input signal are within a predetermined range of respective different prior values of said input signal, and means for providing said command signal when a predetermined number of said determinations have been made.

Claim 42

The apparatus of claim 37, wherein: said receiving and generating means generates a sampler command signal in response to a second predetermined number of said determinations being made, said second predetermined number being less than said first-mentioned predetermined number; and said apparatus further comprises a sampling tool connecting to said housing and including sampler control means for automatically trapping a well fluid sample in said sampling tool in response to said sampler command signal.

Claim 43

The apparatus of claim 37, wherein: said receiving and generating means generates a sampler command signal in response to said determination making means; and said apparatus further comprises a sampling tool connected to said housing and including sampler control means for automatically trapping a well fluid sample in said sampling tool in response to said sampler command signal.

Claim 44

The apparatus of claim 39, wherein: said receiving and generating means generates said sampler command signal in response to said determination making means determining that a current said value of said input signal is within a second predetermined range of a respective prior said value of said input signal, said second predetermined range being larger than said first-mentioned predetermined range.

Claim 45

The apparatus of claim 26, wherein: said predetermined criterion of said receiving and generating means represents a stabilized level at which there is no further significant change in said parameter.

Claim 46

The apparatus of claim 26, Wherein said receiving and generating means comprises means for providing one said command signal to automatically open said shut-in valve element and start a drawdown test when shut-in downhole pressure has substantially peaked.

Claim 47

The apparatus of claim 42, wherein said receiving and generating means comprises means for providing another said command signal to automatically reclose said shut-in valve element when flowing downhole pressure has substantially bottomed out.

Claim 48

The apparatus of claim 26, said production tubing string including a landing nipple at said downhole location, wherein: said setting means is a lock mandrel constructed to be landed in said landing nipple.

Claim 49

The apparatus of claim 26, wherein: said receiving and generating means includes means for generating a sampler command signal when said input signal meets predetermined sampling criterion; and said apparatus further comprises a sampling tool connected to said housing and including sampler control means for automatically trapping a well fluid sample in said sampling tool in response to said sampler command signal.