Valve with pressure energized back seat sealing means
US4474203A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 2, 1983 |
| Grant date | Oct 2, 1984 |
| Priority date | — |
| Expiry date | Sep 2, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/6069
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A valve having a back-sealing capability provided by a pressure energizable sealing assembly which becomes operative independently of valve stem movement and valve element position for sealing between the valve casing (10, 22) and the valve stem (21) in the event of loss of sealing by the valve stem packing (33). A sealing ring (45) of the sealing assembly is installed with limited axial movement in an enlargement (20a) of the valve stem bore located intermediate the valve stem packing (33) and the valve chamber (11). The sealing ring (45) is provided with inner peripheral sealing surfaces (54) and an outer peripheral sealing surface (51) conforming in configuration to that of a corresponding sealing surface (42) provided in the stem bore enlargement. Yieldable spacer means (47) are provided for normally maintaining the sealing ring with the outer peripheral sealing surface (45) of the sealing ring in close proximity to the sealing surface (42) of the valve stem bore enlargement whereby the sealing assembly is responsive to a pressure differential induced across the sealing ring by a stem packing leak to establish a pressure energized metal-to-metal seal between the valve casing an…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.