Expandable stabilizer with roller reamer elements

An expandable reamer apparatus for reaming a borehole in a subterranean formation, comprising:

• a tubular body having a longitudinal axis, an inner bore, an outer surface, a plurality of upwardly and outwardly sloping tracks within the tubular body between the inner bore and the outer surface at an acute angle to the longitudinal axis;
• a drilling fluid flow path extending through the tubular body for conducting drilling fluid therethrough;
• a plurality of circumferentially spaced, generally radially and longitudinally extending blades, each blade slidably engaged with one of the plurality of tracks, carrying at least one roller element thereon and movable along its associated track between an extended position and a retracted position;
• an actuation structure positioned within the tubular body and configured to directly effect movement of the blades in the tracks from the retracted position to the expanded position responsive to a pressure of drilling fluid within the flow path and an opposing force;
• a lowlock sleeve coupled to the actuation structure;
• and
• a traveling sleeve disposed at least partially within the tubular body, wherein a portion of the traveling sleeve abuts a portion of the lowlock sleeve to selectively retain the actuation structure in an initial position and wherein axial translation of the traveling sleeve enables the lowlock sleeve and the actuation structure to axially translate within the tubular body.

An expandable reamer apparatus for reaming a borehole in a subterranean formation, comprising:

• a tubular body having a longitudinal axis, an outer surface, and a track within the tubular body, the track sloped upwardly and outwardly at an acute angle to the longitudinal axis;
• a drilling fluid flow path extending through an inner bore of the tubular body;
• a blade having at least one roller element configured to remove material from a subterranean formation during reaming and slideably coupled to the track;
• a push sleeve disposed within the inner bore of the tubular body and directly coupled to the blade, the push sleeve configured to move axially upward responsive to a pressure of drilling fluid passing through the inner bore to extend the blade along the track;
• a traveling sleeve disposed at least partially within an inner bore of the push sleeve;
• and
• a lowlock sleeve coupled to the push sleeve, wherein a portion of the traveling sleeve forces a portion of the lowlock sleeve into engagement with an inner portion of the tubular body to retain the push sleeve in an initial position and wherein axial translation of the traveling sleeve enables the lowlock sleeve to disengage from the tubular body.

An expandable reamer apparatus for reaming a borehole in a subterranean formation, comprising:

• a tubular body having a longitudinal axis and at least one track within a wall of the tubular body sloped upwardly and outwardly at an acute angle to the longitudinal axis;
• a drilling fluid flow path extending through an inner bore of the tubular body;
• at least one blade having at least one roller element configured to ream the subterranean formation, the at least one blade slideably coupled to the at least one track;
• a push sleeve disposed within the inner bore of the tubular body and directly coupled to the at least one blade, the push sleeve configured to move axially upward responsive to a pressure of drilling fluid passing through the inner bore to extend the at least one blade along the at least one track;
• a traveling sleeve within the tubular body axially retaining the push sleeve in an initial position within the tubular body by engaging at least one retainment feature coupled to the push sleeve;
• a longitudinal biasing element disposed within the inner bore of the tubular body and in contact with the push sleeve;
• and
• a motion-limiting member coupled between the tubular body and the push sleeve to limit an extent of axial movement of the push sleeve responsive to the pressure.

An expandable reamer for reaming a borehole in a subterranean formation, comprising:

• a body having a longitudinal axis;
• a drilling fluid flow path extending through the body for conducting drilling fluid therethrough;
• a plurality of blades carried by the body at an acute angle relative to the longitudinal axis, each blade having at least one roller element coupled thereto;
• an actuator positioned within the body and configured to directly actuate the plurality of blades between an extended position and a retracted position in respective response to a pressure provided by the drilling fluid within the flow path and an opposing force;
• a traveling sleeve disposed at least partially within the body, the traveling sleeve configured to selectively retain the actuator in an initial position;
• and
• a lowlock assembly including a plurality of protrusions, wherein a portion of the traveling sleeve forces the plurality of protrusions of the lowlock assembly into engagement with an inner portion of the tubular body and wherein axial translation of the traveling sleeve enables the plurality of protrusions of the lowlock sleeve to disengage from the inner portion of the tubular body enabling the actuator to axially translate within the tubular body.