Control system for deep set subsurface valves
US6427778B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 2000 |
| Grant date | Aug 6, 2002 |
| Priority date | — |
| Expiry date | May 18, 2020 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B34/14
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The hydraulic control system for operating a flow tube in a subsurface safety valve is disclosed. An isolation piston is used in conjunction with an operating control line and an engagement control line. Both control lines run from the surface. The isolation piston is spring loaded to equalize pressure across a dynamic piston to allow the flow tube to be shifted by a power spring to allow in turn the subsurface safety valve to close. Application of pressure on the engagement control line directs pressure applied through the operating control line to the top of the dynamic piston thus shifting the flow tube downwardly to open the subsurface safety valve. In an alternative embodiment, a coaxial control line directs fluid to the top of the dynamic piston and additionally to a parallel path leading to the bottom of the dynamic piston where a control valve is mounted. The control valve can be actuated hydraulically, electronically or other ways such that when it is closed the pressure applied to the dynamic piston shifts the flow to open the subsurface safety valve. A loss of signal to the control valve equalizes the dynamic piston allowing the flow tube to shift.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.