Patent · US Expired

Different stiffness energizers for MF seals

US5875861A · kind A · utility

16Cited by
31References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 24, 1996
Grant dateMar 2, 1999
Priority date
Expiry dateJul 24, 2016

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE05Y2900/402
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A rolling cutter drill bit has at least one roller cutter mounted on a cantilevered bearing shaft with a sealed bearing and lubrication system, lubricant pressure balancing means, lubricant pressure relief means, and a volume compensating rigid face seal assembly axially movable through an operating range. The face seal assembly comprises two cooperating face seal rings, one ring mounted on the bearing shaft and the other ring mounted in the cutter; a first energizer for the seal ring mounted on the bearing shaft, having a stiffness K1; and a second energizer for the seal ring mounted in the cutter, having a stiffness K2. In order to minimize the variation in the sealing face force as the assembly moves through its operating range, the stiffness K2 is less than half, and preferably less than 0.2, of the stiffness K1.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.