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:
Sep. 14, 2004
Filed:
May. 28, 2003
Robert Denton, Pealand, TX (US);
Smith International, Inc, Houston, TX (US);
Abstract
O-ring seals for rock bit bearings comprise a body formed from an elastomeric material having a lubricant additive in at least the dynamic seal surface to reduce the coefficient of friction and stick-slip amplitude at O-ring seal surfaces. The lubricant additive comprises polarized graphite. O-ring seals made from elastomeric compositions comprise in the range of from about 50 to 99 percent by volume elastomeric material, and in the range of from about 1 to 50 percent by volume of the polarized graphite based on the total volume of the composition. Preferably, the polarized graphite is in the range of from 7 to 25 percent by volume. As the O-ring seal experiences wear from adjacent metal surfaces, flakes of polarized graphite are released from the O-ring seal and adhere to the adjacent metal surfaces and form a lubricating film.