Extended reach drilling system
AssigneeShell Oil Company
InventorBruno Best
Life of this patent
Estimating the term…
Abstract
An extended reach drilling (ERD) system for drilling a borehole in an underground formation is provided. The ERD system comprises a drill bit, a motor for driving the drill bit, a drill-pipe to surface, a hydraulic cylinder/piston arrangement for providing the required weight on bit, the drill-pipe being coupled to a selected one of the cylinder and the piston of the cylinder/piston arrangement such that the drill pipe may rotate relative to the selected one of the cylinder and the piston, the drill bit being coupled to the other one of the cylinder and the piston, and locking members for locking the selected one of the cylinder and the piston against the borehole wall, the locking members being operable between an engaged position and a disengaged position.
Claims12
An extended reach drilling system for drilling a borehole in an underground formation, said extended reach drilling system comprising:
- a) a drill bit;
- b) a motor for driving the drill bit;
- c) a drill-pipe to surface;
- d) a hydraulic cylinder/piston arrangement for providing the required weight on the drill bit, the drill-pipe being coupled to a selected one of the cylinder and the piston of said cylinder/piston arrangement by swivel means allowing rotation of the drill pipe relative to said selected one of the cylinder and the piston, the drill bit being coupled to the other one of the cylinder and the piston, wherein the swivel means comprises a downhole clutch which is operable between a disengaged position in which rotation of the drill-pipe relative to said selected one of the cylinder and the piston is allowed, and an engaged position in which such relative rotation is prevented;
- and
- e) locking means for locking said selected one of the cylinder and the piston against the borehole wall, the locking means being operable between an engaged position and a disengaged position.
Dependencies are inferred from the claim text.