Well fluid pressure balanced operator for subsurface safety valve
US4469180A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 21, 1981 |
| Grant date | Sep 4, 1984 |
| Priority date | — |
| Expiry date | Oct 21, 2001 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/04
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A surface controlled subsurface safety valve having rotatable ball-type closure elements and disclosed the tubular operator assembly is sealed to be substantially pressure balanced with respect to well fluid pressures when the ball-type closure is in either the open or closed position. Such arrangement enables the valve to be opened at a moderate control fluid pressure level with a substantial well pressure differential across the closed ball. In the disclosed tubing retrieval embodiment, an enclosed hydraulic system is used to balance the tubular operation and offset the hydrostatic head of the control fluid to enable greater setting depth.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.