Flapper-type subsurface safety valve
US3958633A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 1975 |
| Grant date | May 25, 1976 |
| Priority date | — |
| Expiry date | May 29, 1995 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/05
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
This is a subsurface safety valve for insertion in a tubing string in a well drilled in the earth, normally for the production of oil and gas. This valve is lowered and retrieved by wireline and is seated in a special side-pocket mandrel which is a part of the tubing string. One suitable valve is a flapper-type, full-opening valve having a folding or collapsing flapper that permits it to retract completely into the side pocket, thereby leaving a full opening through the valve and tubing string when open. The valve may be controlled either by hydraulic pressure transmitted to it from the surface or by subsurface pressure sensing means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.