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:
Apr. 18, 2017
Filed:
Jan. 17, 2013
Applicant:
National Oilwell Varco Norway As, Stavanger, NO;
Inventor:
Age Kyllingstad, Algard, NO;
Assignee:
NATIONAL OILWELL VARCO NORWAY AS, Stavanger, NO;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B 44/00 (2006.01); E21B 41/00 (2006.01);
U.S. Cl.
CPC ...
E21B 44/00 (2013.01); E21B 41/0092 (2013.01);
Abstract
A drillstring with a bit is characterized by controllable variables of vertical and rotational speeds and response variables of axial tension force and torque, referenced to the top of the drillstring. A method of reducing or avoiding at least an axial or a torsional oscillation mode in the drillstring includes: