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:
Jul. 28, 1981
Filed:
Sep. 26, 1979
Clyde A Willis, Wichita Falls, TX (US);
Walker-Neer Mfg. Co., Inc., Wichita Falls, TX (US);
Abstract
In a dual conduit drill pipe section having concentric inner and outer tubes, a plurality of centering lugs are provided which are disposed between the inner and outer tubes and include bearing surfaces which are adapted to reduce the friction and wear associated with the movement of the inner tube with respect to the outer tube. The inner tube is secured to the outer tube at one point along each pipe section by a heat meltable adhesive which bonds an anchor ring which is secured to the inner tube to a shoulder defined in the inner surface of the outer tube.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile