Subsurface tubing safety valve
US5137090A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 3, 1991 |
| Grant date | Aug 11, 1992 |
| Priority date | — |
| Expiry date | May 3, 2011 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/05
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
There is disclosed a subsurface tubing safety valve of the type having a flapper pivotally mounted in the bore of a tubular body disposable in a tubing string, and a flow tube vertically reciprocable within the bore of the body between an upper position permitting the flapper to close the bore and a lower position engaging and moving the flapper into a recess in the side of the bore to open the bore. The flow tube is yieldably urged to its upper position and moved to its lower position in response to the supply of hydraulic fluid from a remote source to a piston engageable with the flow tube, and the flapper is yieldably urged to its closed position by means of an arm pivotally mounted on the body for extension over the lower surface of the flapper and a spring providing a vertically extending force acting between an end of the arm to one side of its pivotal axis and the body to urge the arm to a position to close the flapper.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.