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:
Oct. 06, 1981
Filed:
Feb. 15, 1979
John M Mullins, Houston, TX (US);
Joseph L Kelly, Jr, Houston, TX (US);
Hughes Tool Company, Houston, TX (US);
Abstract
A stabilizer for attachment to drill string in large diameter earth boring or shaft drilling to center the drill string and maintain alignment of the drill bit. The stabilizer has an inner hub that is rigidly secured to the drill string above the bit. A rubber tube inside the inner hub is compressed to lock the inner hub to the drill string. An outer hub encircles the inner hub. A bearing is mounted between the inner hub and outer hub to allow rotation with respect to each other. The bearing includes a frusto-conical ring in contact with individual pads that are exposed to the drilling fluid. A number of arms extend radially outward from the outer hub to centralize the drill string. The arms are telescopingly received in the outer hub and are pinned together by tie bars at their outer ends to allow them to be quickly removed.