Mud Actuated Drilling System

摘要

A technique facilitates drilling of a variety of a wellbores. The technique comprises providing a directional drilling system with a drill bit mounted at the end of a collar having an internal flow passage for drilling fluid. The collar is rotatably positioned in a steering structure to which a plurality of steering members is mounted for lateral motion with respect to the steering structure. The design allows the steering structure to remain rotationally stationary with respect to the surrounding borehole wall as the collar and drill bit are rotated to perform a drilling operation. The drilling orientation of the collar and the drill bit may be adjusted by routing drilling fluid from the internal flow passage to at least one of the steering members to cause lateral displacement of the steering member while the steering structure remains in the rotationally stationary position.

主权项

1. A method for drilling a borehole, comprising:
providing a drill bit at an end of a collar having an internal flow passage: rotatably positioning the collar within a steering sleeve to which a plurality of steering members is mounted for selective lateral motion with respect to the steering sleeve; while maintaining the steering sleeve in a rotationally stationary position with respect to the borehole, rotating the collar and the drill bit to perform a drilling operation; and adjusting a drilling orientation of the collar and the drill bit by routing drilling fluid from the internal flow passage to at least one select steering member to cause the selective lateral motion while the steering sleeve remains in the rotationally stationary position.