The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 16, 2004
Filed:
Jun. 22, 1999
Applicant:
Inventor:
Robert M. Tessari, Calgary, CA;
Assignee:
Tesco Corporation, Calgary, CA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21B 1/100 ;
U.S. Cl.
CPC ...
E21B 1/100 ;
Abstract
A method and apparatus for drilling directional wellbores using a casing string as a drill stem is taught. A retrievable bit is mounted at an end of the casing string and either a mud motor with a bent housing and/or bent sub or a rotary steerable tool is used to direct the bit to drill directionally.