Tandem seal arrangement for mechanical face seals
US5529315A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 1994 |
| Grant date | Jun 25, 1996 |
| Priority date | — |
| Expiry date | Feb 14, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S277/927
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A three-part seal comprising an inboard, an intermediate and an outboard seal and defining two chambers, a mixing chamber between the inboard seal and the intermediate seal and a buffer chamber between the intermediate seal and the outboard seal, provides the capability of zero emissions of a process fluid under pressure in a housing. The process fluid may comprise a toxic or otherwise environmentally hazardous process fluid. A radial bore provides fluid communication between the buffer chamber and a buffer fluid reservoir, for example, a source of nitrogen gas, which is maintained at a pressure, preferably about five to eight psi, over the fluid pressure in the mixing chamber. Spiral grooves on at least one ring of the intermediate seal pump the buffer fluid from the buffer chamber into the mixing chamber where it mixes with any leakage of the process fluid and is evacuated through a second radial bore which provides fluid communication between the mixing chamber and a collection pod for collecting and processing the mixed fluid. A method of providing a zero emission seal between a housing and a relatively rotating shaft is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.