Patent · US Expired

Rock bit with mechanical seal

US5472058A · kind A · utility

22Cited by
9References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 20, 1994
Grant dateDec 5, 1995
Priority date
Expiry dateApr 20, 2014

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16J15/344
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A mechanical seal for use in a rotary rock bit comprises a leg seal ring positioned within a recessed portion of a leg forming a seal cavity. The leg seal comprises one surface partially engaged by a resilient material and an opposite surface comprising a first sealing surface. The mechanical seal also comprises cone seal ring positioned within a portion of a cone forming the seal cavity. The cone seal comprises one surface positioned within and attached to a recessed portion of the cone and another surface comprising a second sealing surface engaging the first sealing surface. The portion of the leg seal ring engaged by the resilient material engages a back face of the leg which includes a ramp, serving to urge the first sealing surface against the adjacent second sealing surface and create a sealing engagement. The first and second sealing surfaces are made from different hard materials each having a similar hardness of greater than 1000, and each material selected has a Knoop hardness difference of about 400 or less. The first and second sealing surfaces may be formed from materials the same as or different than materials forming the leg seal ring and cone seal ring, respectivel…

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