Equalizing valve for subterranean wells
US4478286A · kind A · utility
59Cited by
7References
14Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 14, 1983 |
| Grant date | Oct 23, 1984 |
| Priority date | — |
| Expiry date | Feb 14, 2003 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/05
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The subterranean well safety valve useful in oil and gas wells employs a rotatable flapper to close a fluid production flow path. A through-the-flapper equalizing valve means is employed to equalize pressure across the closed valve in response to movement of an axially shiftable flow tube actuator. A spring-loaded poppet valve extends through the flapper on the periphery of the flapper in alignment with the end of the flow tube. The equalizing valve is opened upon initial movement of the flow tube followed by full opening of the flapper.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.