Expandable apparatus and related methods

摘要

An expandable reamer apparatus and methods for reaming a borehole, wherein a laterally movable blade carried by a tubular body may be selectively positioned at an inward position and an expanded position. The laterally movable blade, held inwardly by blade-biasing elements, may be forced outwardly by drilling fluid selectively allowed to communicate therewith by way of an actuation sleeve disposed within the tubular body. Alternatively, a separation element may transmit force or pressure from the drilling fluid to the movable blade. Further, a chamber in communication with the movable blade may be pressurized by way of a downhole turbine or pump. A ridged seal wiper, compensator, movable bearing pad, fixed bearing pad preceding the movable blade, or adjustable spacer element to alter expanded blade position may be included within the expandable reamer. In addition, a drilling fluid pressure response indicating an operational characteristic of the expandable reamer may be generated.

主权项

1. An expandable apparatus for use in a subterranean formation, comprising:
an elongated body including one or more components and comprising a drilling fluid path; at least one of a plurality of blades and a plurality of bearing pads movably mounted to the
elongated body to enable positioning thereof at a retracted position and at least one extended position; and an actuation mechanism configured to move the at least one of the plurality of blades and the plurality of bearing pads simultaneously and repeatably between the retracted position and the at least one extended position and operable in combination with a drive source selected from the group consisting of pressure of drilling fluid within the drilling fluid path and fluid pressure generated downhole and the actuation mechanism comprises at least one of a hydraulically actuated valve and an electrically actuated valve to selectively control application of the pressure of drilling fluid within the drilling fluid path or the fluid pressure generated downhole to effect the simultaneous, repeatable movement of the at least one of the plurality of blades and the plurality of bearing pads.