EARTH-BORING TOOLS HAVING EXPANDABLE MEMBERS AND RELATED METHODS

摘要

Expandable apparatus for use in subterranean boreholes include a tubular body having at least one opening and at least one member positioned within the at least one opening. The member is configured to move between a retracted position and an extended position. A sleeve member including a constricted portion may be disposed in the tubular body and may selectively retain the at least one member in the retracted position. In some embodiments, the sleeve member may be biased in an initial position. Methods of moving a member of an expandable apparatus include repeating retracting and expanding of the member. Methods of triggering an expandable apparatus include forming a constriction in a fluid flow path extending through a sleeve member to move the sleeve member in a downhole direction responsive to fluid flow.