Patent · US Expired

Spiral groove seal system for high vapor-pressure liquids

US4889348A · kind A · utility

58Cited by
6References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 10, 1987
Grant dateDec 26, 1989
Priority date
Expiry dateJun 10, 2007

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16J15/3424
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A seal system is disclosed for sealing a housing and rotatable shaft against leakage of high vapor-pressure liquids. The method of sealing contemplates phase change of the liquefied hydrocarbon fluid across a first module. The gas so formed is contained by a second seal module which operates as a dry running gas seal. The seal system has plural, axially spaced spiral-groove seal modules mounted between the shaft and housing. Each seal module has a primary ring affixed to the housing and a mating ring affixed for rotation with the shaft and the modules define an intermediate cavity. The rings have opposed, radially extending faces, one of which has a plurality of downstream pumping spiral grooves extending from one circumference. The grooves of the grooved ring of the upstream module are of a depth not to exceed about 100 micro-inches. In a preferred form, the depth of the grooves of the upstream module do not exceed 50 micro-inches. The groove depth of the grooves of the downstream module is greater than the depth of the grooves of the upstream module and may be as much as 200 micro-inches.

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