Method of operating a pressure cycle operated perforating firing head and generating electricity in a subterranean well

摘要: Pressure cycle operated apparatus and methods. A method of actuating a firing head includes the steps of: reciprocably displacing an actuator piston head, step including being alternately pressure balanced unbalanced; igniting combustible material in response to step. generating electricity includes: piston, separating at least two chambers; check valve which permits one-way flow between restrictor restricts biasing device biases toward one pin releasing releases displacement piston.