Control line blow out preventer
US4422503A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 4, 1981 |
| Grant date | Dec 27, 1983 |
| Priority date | — |
| Expiry date | Nov 4, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/8225
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An improved control line blow out preventer valve is provided, having a fluid pressure chamber interposed in a control line extending from a surface control panel to a downhole safety valve in a subterranean well. Axially spaced inlet and outlet openings are provided in the pressure chamber and a piston is reciprocally mounted intermediate the inlet and outlet openings. A sealing plug carried by the piston cooperates with a seal surrounding the inlet opening. A bypass passage through the piston mounts a check valve which permits free fluid flow in the direction from the control panel to the subsurface safety valve but only a restricted fluid flow in the opposite direction. A check valve is mounted in the outlet passage to prevent fluid flow from the subsurface safety valve to the control panel. A fusible link normally maintains this check valve off its seat so that it does not close until the occurrence of an elevated temperature caused by fire. At the inlet port a bleed valve which is thermally activated is incorporated in order to bleed off the safety valve, or other apparatus, pressure in the event of a fire.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.