Safety valve into the wellbore, the ground pressure, pressure by liquid control pipeline is transmitted to the two sealing packing between pore pressure to the piston, push the piston moves downward, and the compression spring, to open the valve, if the control line pressure, safety valve in open position, release control line pressure, by the tension of the spring to push the piston moves up, and the valve is in the closed state. If the loss of the role of safety valve, can be in permanent lock open tools, through the ground pressure or downward shock, cut often kaiding slider pin so that the slider move downward to push the piston, the safety valve in open position forever. The steel wire into recycling insertion type safety valve, the formation of new safety valve system; if you want to ensure working steel below the safety valve, through the wire into the temporary open the tool, to attack the vibration, temporary locking slider to move with the piston at the bottom of the locked together, the safety valve in the temporary open position, after the completion of the steel wire operation, hydraulic control line pressure, safety valve again, in a normal working state.
