Patent Number: 7,086,485

Title: Directional casing drilling

Abstract: A directional drilling system, including a casing string, a casing latch disposed inside the casing string proximate a lower end of the casing string and coupled to the casing string, a rotary steerable system disposed inside the casing string and coupled to the casing latch, and a drill bit coupled to the rotary steerable system.

Inventors: Moriarty; Keith Alan (Houston, TX), Johnson; Michael Robert (Sugar Land, TX)

Assignee: Schlumberger Technology Corporation

International Classification: E21B 10/66 (20060101)

Expiration Date: 8/08/02018