Safety valve utilizing an isolation valve and method of using the same
US6302210A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 10, 1997 |
| Grant date | Oct 16, 2001 |
| Priority date | — |
| Expiry date | Nov 10, 2017 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/05
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A subsurface safety valve has a tubular valve housing, a valve closure member movable between an open and a closed position, an axially shiftable flow tube for opening the valve closure member. Hydraulic pressure from the control line is used to move a piston, which in turn moves an axially shiftable opening prong through the closure member. A balance line, or second hydraulic line is also used to make the valve well insensitive. An isolation valve is placed in the flow path of the second hydraulic line. The isolation valve prevents gas migration into the balance line. It also provides volume control for the fluid displaced when the piston is moved by pressure from the control line. Further, the valve can be closed by the application of sufficient pressure through the second hydraulic line.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.