Downhole adjustable stabilizer and method

A downhole adjustable stabilizer for use in a well bore and along a drill string having a bit at the lower end thereof, the drill string having an interior flow path for passing pressurized fluid through the stabilizer and to the bit, the stabilizer comprising:

• a stabilizer body having an interior passage for fluid communication with the drill string interior flow path, the stabilizer body including an upper end for interconnection with an upper portion of the drill string, a lower end for interconnection to a lower portion of the drill string between the stabilizer and the bit, and an intermediate portion including a plurality of cavities circumferentially spaced about the stabilizer body, each cavity defined at least in part by stabilizer body sidewalls;
• a plurality of stabilizer blades each received within a respective cavity in the stabilizer body, each stabilizer blade being radially movable with respect to the stabilizer body from a retracted position to an expanded position;
• a plurality of radially movable pistons each positioned inwardly of a corresponding stabilizer blade, each piston being radially movable from an inward position to an outward position in response to pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer, the radial movement of each of the pistons mechanically effecting the radial movement of the corresponding stabilizer blade;
• a locking sleeve having one or more sleeve interlocking members and movable within the stabilizer body from an unlocked position to a locked and retracted position, the locking sleeve having a central flow path for transmitting pressurized fluid through the stabilizer body, the axial movement of the locking sleeve to its locked and retracted position fixing the radial position of at least one of the plurality of pistons in its inward position, such that the fixed pistons are prevented from radial outward movement in response to the pressure differential, thereby maintaining the corresponding stabilizer blade in its retracted position;
• and
• at least one of the plurality of pistons including a piston interlocking member for engagement with a corresponding sleeve interlocking member to interconnect the at least one piston and locking sleeve and thereby limit radial outward movement of the corresponding stabilizer blade.

A method of adjusting a downhole stabilizer for use in a well bore positioned along a drill string having an interior flow path for passing pressurized fluid through the stabilizer, the stabilizer including a stabilizer body having an interior passage for fluid communication with the drill string flow path and one or more cavities spaced about the stabilizer body, and one or more stabilizer blades each received within a respective cavity in the stabilizer body and radially movable with respect to the stabilizer body from a retracted position to an expanded position, the method comprising:

• positioning one or more radially movable pistons each inwardly of a corresponding one of the one or more stabilizer blades;
• permanently positioning a movable locking radially inward of and engagable with the one or more pistons member, the locking member being movable between a locked position and an unlocked position;
• simultaneously lowering the one or more radially movable pistons and the locking member into the well bore;
• while the stabilizer is in the well bore, selectively moving the locking member to a locked and retracted position to prevent a pressure differential across the one or more pistons from moving the one or more pistons radially outward, thereby locking the corresponding stabilizer blade in its retracted position;
• and
• while the stabilizer is in the well bore and the locking member is in its unlocked position, passing the pressurized fluid through the stabilizer at an expansion flow rate to create a differential pressure across the one or more pistons to move the one or more pistons radially outward, thereby moving the corresponding stabilizer blade to its expanded position.

A downhole adjustable stabilizer for use in a well bore and along a drill string having a bit at the lower end thereof, the drill string having an interior flow path for passing pressurized fluid through the stabilizer and to the bit, the stabilizer comprising:

• a stabilizer body having an interior passage for fluid communication with the drill string interior flow path, the stabilizer body including an upper end for interconnection with an upper portion of the drill string, a lower end for interconnection to a lower portion of the drill string between the stabilizer and the bit, and an intermediate portion including one or more cavities spaced about the stabilizer body, each cavity defined at least in part by stabilizer body sidewalls;
• one or more stabilizer blades each received within a respective cavity in the stabilizer body, each stabilizer blade being radially movable with respect to the stabilizer body from a retracted position to an expanded position;
• one or more radially movable pistons each positioned inwardly of a corresponding one of the one or more stabilizer blades, each piston being radially movable from an inward position to an outward position in response to pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer, each piston being radially movable with respect to a corresponding stabilizer blade, such that the respective piston may move radially in response to pressure differential without moving the corresponding stabilizer blade, and the radial movement of the one or more pistons functionally controlling the radial movement of the corresponding stabilizer blade;
• and
• a locking member movable within the stabilizer body from an unlocked position to a locked and retracted position for selectively fixing the radial position of at least one of the one or more pistons in its inward position when in the locked position, such that the fixed piston is prevented from radial outward movement in response to the pressure differential, thereby maintaining the corresponding stabilizer blade in its retracted position.

A downhole adjustable stabilizer for use in a well bore and along a drill string having a bit at the lower end thereof, the drill string having an interior flow path for passing pressurized fluid through the stabilizer and to the bit, the stabilizer comprising:

• a stabilizer body having an interior passage for fluid communication with the drill string interior flow path, the stabilizer body including an upper end for interconnection with an upper portion of the drill string, a lower end for interconnection to a lower portion of the drill string between the stabilizer and the bit, and an intermediate portion including one or more cavities spaced about the stabilizer body, each cavity defined at least in part by stabilizer body sidewalls;
• one or more stabilizer blades each received within a respective cavity in the stabilizer body, each stabilizer blade being radially movable with respect to the stabilizer body from a retracted position to an expanded position;
• one or more radially movable pistons each positioned inwardly of a corresponding one of the one or more stabilizer blades, each piston being radially movable from an inward position to an outward position in response to pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer, the radial movement of the one or more pistons functionally controlling the radial movement of the corresponding stabilizer blade;
• a locking member movable within the stabilizer body from an unlocked position to a locked and retracted position for selectively fixing the radial position of at least one of the one or more pistons in its inward position when in the locked position, such that the fixed piston is prevented from radial outward movement in response to the pressure differential, thereby maintaining the corresponding stabilizer blade in its retracted position;
• and
• a flow restriction member within the stabilizer body and secured to the locking member, such that pressurized fluid passing through the stabilizer creates a pressure differential through the flow restriction and exerts a force on the locking member to move the locking member from its unlocked position.

A downhole adjustable stabilizer for use in a well bore and along a drill string having a bit at the lower end thereof, the drill string having an interior flow path for passing pressurized fluid through the stabilizer and to the bit, the stabilizer comprising:

• a stabilizer body having an interior passage for fluid communication with the drill string interior flow path, the stabilizer body including an upper end for interconnection with an upper portion of the drill string, a lower end for interconnection to a lower portion of the drill string between the stabilizer and the bit, and an intermediate portion including one or more cavities spaced about the stabilizer body, each cavity defined at least in part by stabilizer body sidewalls;
• one or more stabilizer blades each received within a respective cavity in the stabilizer body, each stabilizer blade being radially movable with respect to the stabilizer body from a retracted position to an expanded position;
• one or more radially movable pistons each positioned inwardly of a corresponding one of the one or more stabilizer blades, each piston being radially movable from an inward position to an outward position in response to pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer, the radial movement of the one or more pistons functionally controlling the radial movement of the corresponding stabilizer blade;
• and
• a locking member movable within the stabilizer body from an unlocked position to a locked and retracted position, the locking member having a stop surface engagable with at least one of the one or more pistons for mechanically fixing the radial position of at least one of the one or more pistons in its inward position when in the locked position, such that the fixed piston is mechanically prevented from radial outward movement in response to the pressure differential, thereby maintaining the corresponding stabilizer blade in its retracted position.

A downhole adjustable stabilizer for use in a well bore and along a drill string having a bit at the lower end thereof, the drill string having an interior flow path for passing pressurized fluid through the stabilizer and to the bit, the stabilizer comprising:

• a stabilizer body having an interior passage for fluid communication with the drill string interior flow path, the stabilizer body including an upper end for fixed interconnection with an upper portion of the drill string, a lower end for fixed interconnection to a lower portion of the drill string between the stabilizer and the bit, and an intermediate portion including one or more cavities spaced about the stabilizer body, each cavity defined at least in part by stabilizer body sidewalls;
• one or more stabilizer blades each received within a respective cavity in the stabilizer body, each stabilizer blade being radially movable with respect to the stabilizer body from a retracted position to an expanded position, and each stabilizer blade being mounted to the stabilizer body;
• one or more radially movable pistons each positioned inwardly of a corresponding one of the one or more stabilizer blades, each piston being radially movable from an inward position to an outward position in response to pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer, the radial movement of the one or more pistons functionally controlling the radial movement of the corresponding stabilizer blade;
• and
• a locking member movable within the stabilizer body while downhole from an unlocked position to a locked and retracted position for selectively fixing the radial position of at least one of the one or more pistons in its inward position when in the locked position, such that the fixed piston is prevented from radial outward movement in response to the pressure differential, thereby maintaining the corresponding stabilizer blade in its retracted position, the locking member including an axially movable sleeve positioned radially inward of the one or more pistons and having a central flow path for transmitting pressurized fluid through the stabilizer body, the locking sleeve including at least one sleeve interlocking member, and at least one of the one or more pistons including a piston interlocking member for engagement with a corresponding sleeve interlocking member to interconnect the at least one piston and the locking sleeve and thereby limit radial outward movement of the corresponding stabilizer blade.

A downhole adjustable stabilizer for use in a well bore and along a drill string having a bit at the lower end thereof, the drill string having an interior flow path for passing pressurized fluid through the stabilizer and to the bit, the stabilizer comprising:

• a stabilizer body having an interior passage for fluid communication with the drill string interior flow path, the stabilizer body including an upper end for interconnection with an upper portion of the drill string, a lower end for interconnection to a lower portion of the drill string between the stabilizer and the bit, and an intermediate portion including a plurality of cavities circumferentially spaced about the stabilizer body, each cavity defined at least in part by stabilizer body sidewalls;
• a plurality of stabilizer blades each received within a respective cavity in the stabilizer body, each stabilizer blade being radially movable with respect to the stabilizer body from a retracted position to an expanded position;
• a plurality of radially movable pistons each positioned inwardly of a corresponding stabilizer blade, each piston being radially movable from an inward position to an outward position in response to pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer, the radial movement of each of the pistons mechanically effecting the radial movement of the corresponding stabilizer blade;
• a locking sleeve axially movable within the stabilizer body from an unlocked position to a locked and retracted position, the locking sleeve having a central flow path for transmitting pressurized fluid through the stabilizer body, the axial movement of the locking sleeve to its locked and retracted position fixing the radial position of at least one of the plurality of pistons in its inward position, such that the fixed pistons are prevented from radial outward movement in response to the pressure differential, thereby maintaining the corresponding stabilizer blade in its retracted position;
• and
• a locking biasing member for biasing the locking sleeve axially to its unlocked position to permit radial movement of the plurality of pistons in response to the pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer.

A downhole adjustable stabilizer for use in a well bore and along a drill string having a bit at the lower end thereof, the drill string having an interior flow path for passing pressurized fluid through the stabilizer and to the bit, the stabilizer comprising:

• a stabilizer body having an interior passage for fluid communication with the drill string interior flow path, the stabilizer body including an upper end for interconnection with an upper portion of the drill string, a lower end for interconnection to a lower portion of the drill string between the stabilizer and the bit, and an intermediate portion including a plurality of cavities circumferentially spaced about the stabilizer body, each cavity defined at least in part by stabilizer body sidewalls;
• a plurality of stabilizer blades each received within a respective cavity in the stabilizer body, each stabilizer blade being radially movable with respect to the stabilizer body from a retracted position to an expanded position;
• a plurality of radially movable pistons each positioned inwardly of a corresponding stabilizer blade, each piston being radially movable from an inward position to an outward position in response to pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer, the radial movement of each of the pistons mechanically effecting the radial movement of the corresponding stabilizer blade;
• a locking sleeve axially movable within the stabilizer body from an unlocked position to a locked and retracted position, the locking sleeve having a central flow path for transmitting pressurized fluid through the stabilizer body, the axial movement of the locking sleeve to its locked and retracted position fixing the radial position of at least one of the plurality of pistons in its inward position, such that the fixed pistons are prevented from radial outward movement in response to the pressure differential, thereby maintaining the corresponding stabilizer blade in its retracted position;
• and
• each of the plurality of pistons is radially movable with respect to the corresponding stabilizer blade, such that each piston may move radially in response to the pressure differential without moving the corresponding stabilizer blade.

A downhole adjustable stabilizer for use in a well bore and along a drill string having a bit at the lower end thereof, the drill string having an interior flow path for passing pressurized fluid through the stabilizer and to the bit, the stabilizer comprising:

• a stabilizer body having an interior passage for fluid communication with the drill string interior flow path, the stabilizer body including an upper end for interconnection with an upper portion of the drill string, a lower end for interconnection to a lower portion of the drill string between the stabilizer and the bit, and an intermediate portion including a plurality of cavities circumferentially spaced about the stabilizer body, each cavity defined at least in part by stabilizer body sidewalls;
• a plurality of stabilizer blades each received within a respective cavity in the stabilizer body, each stabilizer blade being radially movable with respect to the stabilizer body from a retracted position to an expanded position;
• a plurality of radially movable pistons each positioned inwardly of a corresponding stabilizer blade, each piston being radially movable from an inward position to an outward position in response to pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer, the radial movement of each of the pistons mechanically effecting the radial movement of the corresponding stabilizer blade;
• a locking sleeve axially movable within the stabilizer body from an unlocked position to a locked and retracted position, the locking sleeve having a central flow path for transmitting pressurized fluid through the stabilizer body, the axial movement of the locking sleeve to its locked and retracted position fixing the radial position of at least one of the plurality of pistons in its inward position, such that the fixed pistons are prevented from radial outward movement in response to the pressure differential, thereby maintaining the corresponding stabilizer blade in its retracted position;
• and
• a flow restriction member within the stabilizer body and axially secured to the locking sleeve, such that pressurized fluid passing through the stabilizer creates a differential through the flow restriction and exerts an axial force on the locking sleeve to move the locking sleeve from its unlocked position.

A method of adjusting a downhole stabilizer for use in a well bore positioned along a drill string having an interior flow path for passing pressurized fluid through the stabilizer, the stabilizer including a stabilizer body having an interior passage for fluid communication with the drill string flow path and one or more cavities spaced about the stabilizer body, and one or more stabilizer blades each received within a respective cavity in the stabilizer body and radially movable with respect to the stabilizer body from a retracted position to an expanded position, the method comprising:

• positioning one or more radially movable pistons each inwardly of a corresponding one of the one or more stabilizer blades;
• positioning a movable locking member within the stabilizer body, the locking member being movable between a locked position and an unlocked position;
• biasing the locking member axially to its unlocked position;
• while the stabilizer is in the well bore, transmitting a downward weight-on-bit force through the drill string to overcome the biasing force and move the locking member to a locked and retracted position to prevent a pressure differential across the one or more pistons from moving the one or more pistons radially outward, thereby locking the D corresponding stabilizer blade in its retracted position;
• and
• while the stabilizer is in the well bore and the locking member is in its unlocked position, passing the pressurized fluid through the stabilizer at an expansion flow rate to create a differential pressure across the one or more pistons to move the one or more pistons radially outward, thereby moving the corresponding stabilizer blade to its expanded position.

A method of adjusting a downhole stabilizer for use in a well bore positioned along a drill string having an interior flow path for passing pressurized fluid through the stabilizer, the stabilizer including a stabilizer body having an interior passage for fluid communication with the drill string flow path and one or more cavities spaced about the stabilizer body, and one or more stabilizer blades each received within a respective cavity in the stabilizer body and radially movable with respect to the stabilizer body from a retracted position to an expanded position, the method comprising:

• positioning one or more radially movable pistons each inwardly of a corresponding one of the one or more stabilizer blades;
• positioning a movable locking member within the stabilizer body, the locking member being movable between a locked position and an unlocked position;
• biasing the locking member axially to its unlocked position;
• while the stabilizer is in the well bore, passing the pressurized fluid through the drill string to create a pressure differential which exerts a force on the locking member to overcome the biasing force and move the locking member to a locked and retracted position to prevent a pressure differential across the one or more pistons from moving the one or more pistons radially outward, thereby locking the corresponding stabilizer blade in its retracted position;
• and
• while the stabilizer is in the well bore and the locking member is in its unlocked position, passing the pressurized fluid through the stabilizer at an expansion flow rate to create a differential pressure across the one or more pistons to move the one or more pistons radially outward, thereby moving the corresponding stabilizer blade to its expanded position.

A method of adjusting a downhole stabilizer for use in a well bore positioned along a drill string having an interior flow path for passing pressurized fluid through the stabilizer, the stabilizer including a stabilizer body having an interior passage for fluid communication with the drill string flow path and one or more cavities spaced about the stabilizer body, and one or more stabilizer blades each received within a respective cavity in the stabilizer body and radially movable with respect to the stabilizer body from a retracted position to an expanded position, the method comprising:

• positioning one or more radially movable pistons each inwardly of a corresponding one of the one or more stabilizer blades;
• positioning a movable locking member within the stabilizer body, the locking member being movable between a locked position and an unlocked position;
• biasing the locking member axially upward to its unlocked position;
• while the stabilizer is in the well bore, selectively moving the locking member to a locked and retracted position to prevent a pressure differential across the one or more pistons from moving the one or more pistons radially outward, thereby locking the corresponding stabilizer blade in its retracted position;
• while the stabilizer is in the well bore and the locking member is in its unlocked position, passing the pressurized fluid through the stabilizer at an expansion flow rate to create a differential pressure across the one or more pistons to move the one or more pistons radially outward, thereby moving the corresponding stabilizer blade to its expanded position;
• selectively altering the upward biasing force on the locking member, such that the locking member is selectively subjected to one of a relatively large biasing force and a relatively small biasing force;
• the step of selectively moving the locking member to its locked and retracted position includes altering the biasing force to the relatively small biasing force;
• and
• thereafter passing pressurized fluid at a flow rate through the locking member less than the expansion flow rate to create a pressure differential to move the locking member to its locked and retracted position.

A method of adjusting a downhole stabilizer for use in a well bore positioned along a drill string having an interior flow path for passing pressurized fluid through the stabilizer, the stabilizer including a stabilizer body having an interior passage for fluid communication with the drill string flow path and one or more cavities spaced about the stabilizer body, and one or more stabilizer blades each received within a respective cavity in the stabilizer body and radially movable with respect to the stabilizer body from a retracted position to an expanded position, the method comprising:

• positioning one or more radially movable pistons each inwardly of a corresponding one of the one or more stabilizer blades;
• positioning a movable locking member within the stabilizer body, the locking member being movable between a locked position and an unlocked position;
• mechanically interconnecting each of the one or more radially movable pistons and a corresponding stabilizer blade such that each radially movable piston may move radially in response to the pressure differential without moving the corresponding stabilizer blade;
• while the stabilizer is in the well bore, selectively moving the locking member to a locked and retracted position to prevent a pressure differential across the one or more pistons from moving the one or more pistons radially outward, thereby locking the corresponding stabilizer blade in its retracted position;
• and
• while the stabilizer is in the well bore and the locking member is in its unlocked position, passing the pressurized fluid through the stabilizer at an expansion flow rate to create a differential pressure across the one or more pistons to move the one or more pistons radially outward, thereby moving the corresponding stabilizer blade to its expanded position.

A downhole adjustable stabilizer for use in a well bore and along a drill string having a bit at the lower end thereof, the drill string having an interior flow path for passing pressurized fluid through the stabilizer and to the bit, the stabilizer comprising:

• a stabilizer body having an interior passage for fluid communication with the drill string interior flow path, the stabilizer body including an upper end for interconnection with an upper portion of the drill string, a lower end for interconnection to a lower portion of the drill string between the stabilizer and the bit, and an intermediate portion including a plurality of cavities circumferentially spaced about the stabilizer body, each cavity defined at least in part by stabilizer body sidewalls;
• one or more stabilizer blades each received within a respective cavity in the stabilizer body, each stabilizer blade being radially movable with respect to the stabilizer body from a retracted position to an expanded position;
• one or more radially movable piston means each positioned inwardly of a corresponding stabilizer blade, each piston means being radially movable from an inward position to an outward position in response to pressure differential between the interior flow path within the stabilizer body and the well bore exterior of the stabilizer, the radial movement of each of the piston means mechanically effecting the radial movement of the corresponding stabilizer blade;
• a locking member movable within the stabilizer body from a first stabilizer blade retracted position to a second stabilizer blade expanded position, the one or more piston means having means for mechanically preventing the locking member from moving to at least one of the first position and second position unless each of the one or more piston means are radially moved to their inward position and outward position, respectively;
• and
• an indicator means indicating the position of the locking member in its first position and in its second position, thereby providing a signal indicative of the position of the one or more stabilizer blades in their retracted position and expanded position, respectively.

A method of adjusting a downhole stabilizer for use in a well bore positioned along a drill string having an interior flow path for passing pressurized fluid through the stabilizer, the stabilizer including a stabilizer body having an interior passage for fluid communication with the drill string flow path and one or more cavities spaced about the stabilizer body, and one or more stabilizer blades each received within a respective cavity in the stabilizer body and radially movable with respect to the stabilizer body from a retracted position to an expanded position, the method comprising:

• positioning one or more radially movable pistons each inwardly of a corresponding one of the one or more stabilizer blades;
• permanently positioning a movable locking member within the stabilizer body, the locking member being movable between a first stabilizer blade retracted position to a second stabilizer blade expanded position;
• simultaneously lowering the one or more radially movable pistons and locking member into the well bore;
• while the stabilizer is in the well bore, mechanically preventing the locking member from moving to at least one of the first position and the second position unless each of the one or more pistons are radially moved to their inward position and outward position, respectively;
• indicating the position of locking member in the first position and in the second position, thereby providing a signal indicative of the position of the one or more stabilizer blades in their retracted position and expanded position, respectfully.