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:
May. 16, 1995
Filed:
Jan. 24, 1994
Applicant:
Inventors:
Richard C Lyon, Denver, CO (US);
William M Conn, Ponca City, OK (US);
Assignee:
Smith International, Inc., Houston, TX (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ; E21B / ;
U.S. Cl.
CPC ...
175331 ; 761082 ; 175401 ; 175408 ;
Abstract
A method to back ream a borehole drilled with a roller cone drill bit is taught. Protruding hard metal cutting inserts are affixed on the upper outside diameter tapered shoulder of each of the bit legs. If the borehole closes to a smaller diameter than the bit gage diameter or loose rock rubble packs around the upper portion of the bit, the protruding cutting inserts fixed on the upper leg tapered shoulder portion back ream the borehole by lifting and rotating the bit.