Method of disabling and locking open a safety valve with releasable flow tube for flapper lockout
US7137452B2 · kind B2 · utility
18Cited by
22References
19Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 25, 2002 |
| Grant date | Nov 21, 2006 |
| Priority date | — |
| Expiry date | Mar 11, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/8811
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A safety valve has a lock open feature that is actuated by expanding or penetrating the flow tube to disconnect the link between the piston in the hydraulic control system and the flow tube. In normal operation, downward movement of the piston moves the flow tube against a power spring. When the flow tube is expanded, penetrated, or otherwise altered, the piston no longer acts on the flow tube and the flow tube can be simply pushed down and locked in position with the flapper wide open.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.