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:
Apr. 04, 1995
Filed:
Dec. 21, 1993
Tommy M Warren, Coweta, OK (US);
Lawrence A Sinor, Tulsa, OK (US);
Amoco Corporation, Chicago, IL (US);
Abstract
An anti-whirl underreamer comprising a body configured for connection to a drillstring, at least two arms carried by the body which are extendable between a retracted position and a projected position, a movable piston and biased spring assembly for moving the arms, a plurality of cutting elements carried by one of the arms for cutting an axially extending cylindrical sidewall of the borehole within a subterranean formation and for applying a resultant radial force to the body as it rotates, and a low friction bearing region carried by another arm for transmitting the resultant radial force from the body to the sidewall of the borehole during rotation of the underreamer within the borehole. The cutting elements are positioned so that the resultant radial force developed is of sufficient magnitude and direction to substantially maintain the low friction bearing region in contact with the sidewall of the borehole as the underreamer is rotated within the borehole.