Spiral groove seal arrangement for high vapor-pressure liquids
US5071141A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 1990 |
| Grant date | Dec 10, 1991 |
| Priority date | — |
| Expiry date | Jul 17, 2010 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16J15/3412
- 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 such as natural gas. The method of sealing comtemplates 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 have a pattern which upon shaft rotation creates shear heating of the liquefied hydrocarbon fluid. The pattern has a land/groove surface area ratio greater than one and preferably a ratio of approximately three. The dam portion relative to groove portion surface area is also preferably greater than one and the preferred dam/groove ratio is approximately three.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.