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. 21, 2017
Filed:
Nov. 08, 2010
Walter Aldred, Thriplow, GB;
Ashley Johnson, Milton, GB;
Dean Gardner, Selsdon, GB;
Maurice Ringer, Bracken Ridge, AU;
Devi Putra, Cambridge, GB;
Walter Aldred, Thriplow, GB;
Ashley Johnson, Milton, GB;
Dean Gardner, Selsdon, GB;
Maurice Ringer, Bracken Ridge, AU;
Devi Putra, Cambridge, GB;
SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US);
Abstract
A drill string suitable for use in directional drilling of a borehole, comprising a rotatable shaft at the leading end of which is a drill bit, and wherein the shaft comprises a variable friction inducing member, which provides rotational friction by physical contact with an inside face of the borehole, the friction inducing member being arranged to exert a first rotational frictional force when the shaft in the vicinity of the member is substantially rotating and a second rotational frictional force when the shaft in the vicinity of the member is substantially not rotating, wherein the first rotational frictional force is less than the second rotational frictional force.