Pressure-controlled well tester operated by one or more selected actuating pressures

A well tool adapted to be positioned in a well bore and to conduct fluids produced from an earth formation into a pipe string extending upwardly to the surface, comprising:

• a tubular body having an axial flow passage and arranged to be tandemly connected in a pipe string;
• tester valve means in said tubular body arranged to open said flow passage in response to an increase of the pressure of the well annulus fluids to a first pressure level above normal hydrostatic;
• means for closing said tester valve means in response to a subsequent decrease of the pressure of the well annulus fluids to a value below said first pressure level including a chamber in said tubular body, and floating piston means dividing said chamber into a first portion for containing a compressible fluid and a second portion adapted to be filled by well bore fluids;
• reference valve means on said tubular body for controlling the admission of well bore fluids to said second chamber portion including passage means communicating said second chamber portion with the well bore, a valve element movable from a passage-opening first position permitting well annulus fluids to flow through said passage means into said second chamber portion to a second, passage-closing position;
• annulus pressure operated means operable upon an increase of the pressure of the well annulus fluids to a predetermined value that is less than said first pressure level to enable said valve element to move to said closed position and thereby trap well bore fluids at a reference pressure in said second chamber portion which is transmitted to said compressible fluid by said floating piston, said annulus pressure operated means including,
• means defining a piston actuator chamber in said tubular body,
• a rupture disc normally blocking the entrance of well annulus fluids into said piston actuator chamber and adapted to open upon an increase of the well annulus pressure to at least said second pressure level for admitting well annulus fluids into said piston actuator chamber,
• a piston actuator arranged in said piston actuator chamber for moving said first valve means to said passage-closing position upon admission of well annulus fluids into said piston actuator chamber;
• and valve structure means cooperatively arranged for normally blocking fluid communication between said axial flow passage and the well annulus and operable when said tester valve means is closed to provide fluid communication between the well annulus and said axial flow passage when the pressure in said axial flow passage is lower than the well annulus pressure by at least a first predetermined differential as well as when the pressure in said axial flow passage is greater than the well annulus pressure by at least a second predetermined differential.

A well tool adapted to be lowered in a well bore and coupled to a well packer to conduct connate fluids produced from an isolated earth formation into a pipe string leading up to the surface, comprising:

• a tubular body having an axial flow passage and arranged to be tandemly connected in a pipe string;
• tester valve means in said body operable for opening said axial flow passage in response to an increase of well bore annulus pressure to a first pressure level above normal hydrostatic;
• means for closing said tester valve means in response to a subsequent decrease of the well bore annulus pressure to a value below said first pressure level including means defining a chamber in said body, pressure-transmitting piston means dividing said chamber into a first portion for containing a compressible fluid and a second portion adapted to receive well bore fluids, and resilient means for applying actuating force to said tester valve means to cause closure thereof;
• reference valve means on said body for controlling the admission of well annulus fluids into said second chamber portion including a first passage intercommunicating the well annulus and said second chamber portion, said reference valve means including a reference valve element having an initial passage-opening position and being movable to a passage-closing position, an actuator piston chamber, an actuator piston movable in said actuator chamber and operable for moving said reference valve element to its said passage-closing position to trap well annulus fluids under pressure in said second chamber portion, and closure means normally blocking the entrance of well annulus fluids into said actuator chamber and operable to admit well bore fluids into said actuator chamber in response to an increase of the well annulus pressure to a second pressure level that is significantly less than said first pressure level;
• and
• relief valve means on said body including a valve member arranged for controlling communication between the well annulus and said axial passage and movable between a normally closed position and an open position, and valve-actuating means operable for moving said relief valve member to its open position for selectively intercommunicating the well bore annulus and said axial flow passage when the fluid pressure in said axial flow passage is lower than the well annulus pressure by at least a first predetermined pressure differential as well as when the fluid pressure in said axial flow passage is greater than the well annulus pressure by at least a second predetermined pressure differential.

A well tool adapted to be positioned in a fluid-filled well bore to conduct fluids produced from an earth formation into a pipe string that leads upward to the surface, comprising:

• a tubular body defining an axial flow passage and arranged to be tandemly connected in a pipe string;
• tester valve means on said body for controlling fluid communication through said flow passage and including means for opening said tester valve means in response to an increase of well bore annulus pressure to at least a first pressure level and for closing said tester valve means upon a decrease of the well bore annulus pressure to a value below said first pressure level, said opening means including a chamber, pressure-transmitting means dividing said chamber into a first chamber portion for containing a compressible fluid and a second chamber portion adapted to receive well bore annulus fluids, said closing means comprising a coil spring that is adapted when compressed to apply closing force;
• pressure reference valve means including a first passage communicating well annulus fluids with said second chamber portion, a valve element normally open to admit well annulus fluids through said first passage into said second chamber portion, and piston means operable in response to an increase of the well annulus pressure to a second pressure level that is substantially less than said first pressure level for closing said valve element to trap well annulus fluids in said second chamber portion at a pressure that is transmitted to said compressible fluid contained in said first chamber portion by said pressure-transmitting means;
• and
• relief valve means on said body for selectively controlling the pressure differential between said flow passage and said annulus when said tester valve means is closed and including a second passage in communication with the exterior of said body, second valve means normally open for admitting well bore fluids into said second passage, means operable in response to closing of said reference valve means for closing said second valve means, first pressure-responsive actuating means operable for moving said relief valve means away from its said passage-closing position when the pressure in said flow passage exceeds the well annulus pressure, biasing means normally maintaining said relief valve member in its said passage-closing position and responsive to a pressure force of a first predetermined magnitude applied to said first actuating means to allow movement of said relief valve member to its said open position, second pressure-responsive actuating means arranged on said relief valve member operable when the pressure in said flow passage is less than the well bore annulus pressure for moving said relief valve member away from its said passage-closing position, and means normally preventing said second actuating means from moving said relief valve member away from its said passage-closing position and responsive to a pressure force of a second predetermined magnitude applied to said second actuating means for moving said relief valve member to its said open position.

A well tool for positioning in a well bore to conduct fluids produced from an earth formation into a pipe string comprising:

• a tubular body defining an axial flow passage and arranged to be tandemly connected in a pipe string;
• normally-closed means on said body initially blocking fluid communication through said axial flow passage and arranged to be opened from the surface to open said axial flow passage;
• first bypass valve means on said body including a bypass passage intercommunicating the well bore with said axial passage, a first valve member arranged to control communication between the well bore and said bypass passage and movable from an initial passage-opening position to a final passage-closing position, first valve-actuating means including a chamber in said body, a piston actuator in said chamber and operatively coupled to said first valve member for moving said first valve member to its said final passage-closing position to permanently close said bypass passage upon admission of well bore fluids into said chamber, and closure means normally blocking the admission of well bore fluids into said chamber and selectively opened only in response to an increase of the well bore pressure to at least a predetermined pressure for said first valve-actuating means to move said first valve member to its said final passage-closing position;
• and
• second bypass valve means on said body including a second valve member arranged to control communication between said axial passage and said bypass passage and selectively movable between a normal passage-closing position and a passage-opening position for intercommunicating said axial flow passage and said bypass passage, and second valve-actuating means operable for moving said second valve member to its said passage-opening position for selectively intercommunicating the well bore and said axial flow passage when the pressure in said axial flow passage is lower than the well bore pressure by at least a first predetermined pressure differential as well as when the pressure in said axial flow passage is greater than the well bore pressure by at least a second predetermined pressure differential.

A bypass valve for controlling the pressure differential between the interior and exterior of a pipe string positioned in a well bore and comprising:

• a tubular body defining an axial flow passage and arranged to be tandemly connected in a pipe string;
• first bypass valve means on said body including a bypass passage intercommunicating the well bore with said axial passage, a first valve member for controlling fluid communication between the well bore and said bypass passage and movable from an initial passage-opening position to a final passage-closing position, first valve-actuating means including means defining a chamber, a piston actuator in said chamber operatively coupled to said first valve member to move said first valve member to its said final passage-closing position for permanently closing said bypass passage when well bore fluids are admitted into said chamber, and pressure-responsive closure means normally blocking the admission of well bore fluids into said chamber and selectively opened only in response to an increase of the well bore pressure to at least a predetermined pressure level for said first valve-actuating means to selectively move said first valve member to its said final passage-closing position;
• and
• second bypass valve means on said body including a second valve member arranged for controlling fluid communication between said bypass passage and said axial passage and movable between a normal passage-closing position and a passage-opening position for admitting well bore fluids in said bypass passage into said axial flow passage, and second valve-actuating means operable for moving said second valve member to its said passage-opening position for selectively intercommunicating the well bore and said axial flow passage when the fluid pressure in said axial flow passage is lower than the well bore pressure by at least a first predetermined pressure differential as well as when the fluid pressure in said axial flow passage is greater than the well bore pressure by at least a second predetermined pressure differential.

A well tool adapted to be positioned in a well bore and to conduct fluids produced from an earth formation into a pipe string extending upwardly to the surface, comprising:

• a tubular body having an axial flow passage and arranged to be tandemly connected in a pipe string;
• tester valve means in said tubular body arranged to open said flow passage in response to an increase of the pressure of the well annulus fluids to a first pressure level above normal hydrostatic;
• means for closing said tester valve means in response to a subsequent decrease of the pressure of the well annulus fluids to a value below said first pressure level including a chamber in said tubular body, and floating piston means dividing said chamber into a first portion for containing a compressible fluid and a second portion adapted to be filled by well bore fluids;
• reference valve means on said tubular body for controlling the admission of well bore fluids to said second chamber portion including passage means communicating said second chamber portion with the well bore, a valve element movable from a passage-opening first position permitting well annulus fluids to flow through said passage means into said second chamber portion to a second, passage-closing position;
• annulus pressure operated means operable upon an increase of the pressure of the well annulus fluids to a predetermined value that is less than said first pressure level to enable said valve element to move to said closed position and thereby trap well bore fluids at a reference pressure in said second chamber portion which is transmitted to said compressible fluid by said floating piston;
• a valve structure cooperatively arranged on said tubular body for controlling the pressure differential between fluids in said axial flow passage below said tester valve element and the well annulus fluids so long as said tester valve element is closed, said valve structure including,
• a valve member arranged for movement in said tubular body between a flow-blocking position preventing fluid communication between said axial flow passage and the well bore and another position providing fluid communication between said axial flow passage and the well bore,
• first pressure-responsive valve-actuating means for moving said valve member to its said other position when the pressure in said axial flow passage increases above the well bore pressure,
• biasing means normally maintaining said valve member in its flow-blocking position and operable to allow said valve member to be moved to its other position only when a pressure differential of at least a first predetermined magnitude acts on said first valve-actuating means,
• second pressure-responsive valve-actuating means operable for moving said valve member to its said other position when the pressure in said axial flow passage decreases below the well bore pressure, and
• force-supplementing means normally preventing said second valve-actuating means from moving said valve member to its other position and operable for allowing said valve member to be moved to its other position only when a pressure differential of at least a second predetermined magnitude acts on said second valve-actuating means.