Gas lubricated barrier seal
US5713576A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 1994 |
| Grant date | Feb 3, 1998 |
| Priority date | — |
| Expiry date | Sep 29, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S277/927
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A double, back to back oriented mechanical end face seal arrangement for use in sealing pumps or other devices used in fluid transfer of toxic or corrosive fluid has an intermediate buffer fluid chamber into which a relatively inert gas, such as nitrogen, is provided for use as a buffer fluid, and is maintained at a pressure which exceeds the process fluid pressure by at least 10 p.s.i. Each seal has a primary ring and a mating ring with gap maintaining means, such as spiral pumping grooves, formed in one of the rings which are shaped and dimensioned to pump the buffer gas through the first seal from the intermediate chamber into the process fluid chamber against the process fluid pressure and through the second seal from the intermediate chamber into the environment external to the housing and sealing area, thus avoiding the escape of the process fluid into the intermediate buffer chamber and thereby to the atmosphere. The inboard seal includes a first secondary sealing means disposed between one seal ring and the housing for sealing therebetween and a second secondary sealing means, disposed between the other seal ring and the shaft for sealing therebetween, the first and second …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.