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. 06, 2001
Filed:
Jan. 06, 1998
Applicant:
Inventor:
James Jing Yao, Mississauga, CA;
Assignee:
Boart Longyear, Inc., Mississauga, CA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16B 7/00 ; E21B 1/702 ;
U.S. Cl.
CPC ...
F16B 7/00 ; E21B 1/702 ;
Abstract
A drill rod for a drill string has a thread at each end and is connected to an adjacent rod by a sleeve. The threads on the sleeve and rod are configured to reduce stress concentrations and provide sacrificial wear on the sleeve. The thread has a single start with a part circular root and the wear volume on the sleeve is less than that on the rod. The outer diameter of the rod is at least twice that of the inner bore.