| 摘要 |
The present application discloses a down-hole safety valve which is controlled from the surface, characterized in that it contains a novel mechanism based on a synchronized action of a plurality of hydraulic actuators and a hydraulic annular piston which allow a sliding tubular-like sleeve to slide for removing sediments which could otherwise interfere with the emergency shut in mechanism of the valve. A method of cleaning the emergency shut in mechanism for the subsurface safety valve enables the cleaning process to be performed without stopping the oil well production. |
