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.

Date of Patent:
Apr. 21, 2009

Filed:

Feb. 08, 2005
Applicants:

John Hughes, Calgary, CA;

Tommy M. Warren, Coweta, OK (US);

Inventors:

John Hughes, Calgary, CA;

Tommy M. Warren, Coweta, OK (US);

Assignee:

Tesco Corporation, Calgary, AB, CA;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B 10/64 (2006.01);
U.S. Cl.
CPC ...
Abstract

A retrievable center bit for use with a tubular including an inner bore and a drill shoe cutter mounted thereon. The retrievable center bit may include a body positionable in the bore of the tubular and including an upper end, a lower end and a side outer surface extending therebetween. A cutting surface may be supported on the lower end of the bit body. There may be a locking assembly on the body for releasably locking the bit axially and rotationally to the tubular. A longitudinal bore may extend from the upper end into the body and the body may include a fluid port extending from the bore to open on the cutting surface and a lateral fluid port extending from the bore opening on the side outer surface positionable adjacent the drill shoe cutter when the bit is locked to the tubular.


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