Pressure balanced piston for subsurface safety valves
US7743833B2 · kind B2 · utility
18Cited by
6References
21Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 24, 2008 |
| Grant date | Jun 29, 2010 |
| Priority date | — |
| Expiry date | Feb 5, 2028 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/05
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A control system for a subsurface safety valve references the surrounding annulus to put the operating piston in pressure balance. Depending on the configuration and which seal in the system fails, the various embodiments can differ in their failure modes. With the lower end of the piston exposed to annulus pressure all failure modes close the flapper. With the lower end of the piston exposed to tubing pressure, failure of any of the seals except one will result in flapper closure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.