Extendable cutting tools for use in a wellbore

摘要

EXTENDABLE CUTTING TOOLS FOR USE IN A WELLBORE A tool (100) for use in a wellbore, comprising a first tubular body (5) having a bore therethrough and an opening (5o) through a wall thereof; a first arm (50a,b): pivotally connected to the body (5) or a first piston (10), disposed in the opening (5o) in a retracted position, and movable to an extended position where an outer surface of the first arm (50a,b) extends outward past an outer surface of the first tubular body (5); the first piston (10): disposed in the body (5) bore, having a bore therethrough, and operable to move the first arm (50a,b) from the retracted position to the extended position in response to fluid pressure in the first piston (10) bore exceeding fluid pressure in the opening (5o); a lock (230) operable to retain the first piston (10) in the retracted position; and a controller (325) operable to release the lock (230) in response to receiving a first instruction signal.