Tubing pressure insensitive control system
US7591317B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 2006 |
| Grant date | Sep 22, 2009 |
| Priority date | — |
| Expiry date | Dec 7, 2027 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B34/10
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A control system can be used with a single control line to a subsurface safety valve. The operating piston is exposed to the flow tube between two blocks with near identical seals to make the piston insensitive to tubing pressure. A control system seal is carried by the piston in the upper block and a passage between the control system seal and the tubing pressure seal in the upper block communicates to a compressible fluid reservoir in the lower block that is also isolated from tubing pressure by a tubing pressure seal. Movement of the piston compresses the fluid in the reservoir. The reservoir can also include a spring to return the piston and the flow tube to a position to close the valve. A redundant system can be actuated if the primary system fails.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.