Surface controlled subsurface safety valve
US4723606A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 1987 |
| Grant date | Feb 9, 1988 |
| Priority date | — |
| Expiry date | Jan 13, 2007 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/05
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A surface controlled subsurface safety valve for use in a well tubing string including a valve closure member, an operator tube for opening the valve closure member and holding it open, an annular piston on the operator tube operative in response to control fluid pressure conducted from the well surface, a spring biasing the operator tube to a position at which the valve is closed, and a lockout sleeve mounted in tandem with the operator tube for movement simultaneously with the operator tube to a position at which the lockout sleeve holds the valve open. The operator tube and lockout sleeve are engageable by a shifting tool to operate the operator tube and lockout sleeve simultaneously. The lockout sleeve can be returned to an inoperative position by control fluid pressure moving the operator tube to a position which opens the valve closure member. The safety valve is also operable by a modified shifting tool engaging the operator tube. The shifting tool includes selective keys and separate expandable latch dogs for simultaneous coupling of the operator tube and the lockout sleeve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.