Graphite packing
US5299812A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 1992 |
| Grant date | Apr 5, 1994 |
| Priority date | — |
| Expiry date | Dec 15, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S277/946
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A fluid valve graphite packing assembly with graphite packing rings and thin PTFE disc rings surrounding an operating valve member. Softer graphite packing rings on the interior are bounded by progressively harder graphite packing rings. A PTFE disc ring is inserted between the graphite packing rings. The packing is subjected to sufficient packing stress to cause the PTFE disc rings to extrude onto the operating valve member. A laminated packing ring formed of alternating sheets of flexible graphite and PTFE which is die cut to provide a crown shaped cross-section aiding in enabling PTFE extrusion to enhance valve operating member lubrication and sealing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.