Annulus shut-off mechanism
US4903774A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 17, 1989 |
| Grant date | Feb 27, 1990 |
| Priority date | — |
| Expiry date | Jan 17, 2009 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B33/047
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An annulus shut-off mechanism with fail-as-is logic suitable for use for example, in a concentric tubing hanger of an oil well, particularly a sub-sea well, has an enclosure across the annulus with inlet and exit ports, a sleeve with an aperture that slides within the enclosure, primary means for sliding the sleeve in the enclosure to bring the aperture into alignment with the inlet and exit ports and secondary means for sliding the sleeve in the event of failure of the primary means. The primary enclosure and sleeve are sealed from access to annulus fluids and may be vertically orientated in the tubing hanger. The secondary means may be a secondary enclosure with a secondary sleeve which can pull or push on the primary sleeve. Both primary and secondary means can be operated by hydraulic pressure, but the two means are independent and the secondary means may be located in a well part other than the tubing hanger.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.