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. 05, 1987
Filed:
Oct. 23, 1985
Applicant:
Inventor:
Hwa-shan Ho, Spring, TX (US);
Assignee:
NL Industries, Inc., New York, NY (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21B / ; E21B / ;
U.S. Cl.
CPC ...
175 27 ; 175 45 ; 175 61 ;
Abstract
A method and apparatus for obtaining complete loading on a drill bit at the end of a drill string in a borehole employ at least three rosette strain gauges uniformly disposed on an instrument sub to measure torque and axial force on the sub, two bending moments in mutually perpendicular directions, and two shear forces in mutually perpendicular directions. These measurements are used to obtain torque on bit, weight on bit, two side forces on the bit normal to each other, and two bending moments on the bit normal to each other which, in turn, can be used to control the bit movement.