Pilot-operated pressure-equalizing mechanism for subsurface valve
US6296061A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 9, 1999 |
| Grant date | Oct 2, 2001 |
| Priority date | — |
| Expiry date | Dec 9, 2019 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/05
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A subsurface valve with a pressure-equalizing mechanism is provided to permit pressure above and below a valve closure member to equalize prior to the opening of the valve closure member. The pressure-equalizing mechanism may be installed, for example, in the valve closure member or in an annular housing in the subsurface valve. The mechanism includes a pilot activator disposed for reciprocal movement within a pilot bore. A flow tube that is disposed for longitudinal movement with a longitudinal bore of the subsurface valve is used to shift the pilot activator within the pilot bore from a closed or sealed position to an open or equalizing position. In the open position, fluid pressure below the valve closure member is allowed to flow through a pilot passageway that establishes fluid communication between the pilot bore and a cylinder within which a pilot piston is moveably disposed. Exposure of the pilot piston to fluid pressure below the valve member moves the pilot piston within the cylinder, which in turn moves an equalizing plug that is disposed for reciprocal movement within a plug bore from a closed or sealed position to an open or equalizing position. Movement of the equaliz…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.