Equalizing annulus valve
US4460040A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 24, 1982 |
| Grant date | Jul 17, 1984 |
| Priority date | — |
| Expiry date | Nov 24, 2002 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B43/122
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An equalizing annulus valve for use in controlling flow in the annulus between two tubular conduits in a subterranean oil or gas well has a control pressure responsive main valve piston and a booster piston for closing radial flow ports. The booster piston is spring loaded relative to the main piston and excess annulus pressure below the valve acts on the booster piston rather than on the main piston. The main piston can be partially opened before abutting the booster piston to permit pressure below the valve to meter through an equalizing port in the main piston and through the main flow ports. When the pressure is equalized, the main piston and booster piston can be shifted to a fully open position. An auxiliary piston responsive to an increase in annulus pressure can also be used to shift the main piston.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.