Method of operating a pressure cycle operated perforating firing head and generating electricity in a subterranean well
First Claim
1. A method of actuating a firing head in a subterranean well, the method comprising the steps of:
- increasing a pressure applied to an actuator piston of the firing head, wherein the actuator piston is not displaced during the pressure increasing step;
then decreasing the pressure, thereby causing reciprocation of the actuator piston of the firing head; and
igniting a combustible material in response to a first predetermined number of reciprocations of the actuator piston.
0 Assignments
0 Petitions
Accused Products
Abstract
Pressure cycle operated apparatus and methods. A method of actuating a firing head includes the steps of: reciprocably displacing an actuator piston of the firing head, the displacing step including the piston being alternately pressure balanced and unbalanced; and igniting a combustible material in response to the piston displacing step. A method of generating electricity includes: reciprocably displacing a piston, the displacing step including the piston being alternately pressure balanced and unbalanced; and generating electricity in response to the piston displacing step. A firing head includes an actuator piston separating at least two chambers; a check valve which permits one-way flow between the chambers; a flow restrictor which restricts flow between the chambers; a biasing device which biases the piston toward one of the chambers; and a firing pin releasing device which releases a firing pin in response to displacement of the piston.
49 Citations
12 Claims
-
1. A method of actuating a firing head in a subterranean well, the method comprising the steps of:
-
increasing a pressure applied to an actuator piston of the firing head, wherein the actuator piston is not displaced during the pressure increasing step; then decreasing the pressure, thereby causing reciprocation of the actuator piston of the firing head; and igniting a combustible material in response to a first predetermined number of reciprocations of the actuator piston. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method of generating electricity in a subterranean well, the method comprising the steps of:
-
reciprocably displacing a piston in the well, the displacing step including the piston being alternately pressure balanced and unbalanced; and generating electricity in response to the piston displacing step, wherein the piston separates first and second chambers, and wherein the piston displacing step further comprises applying pressure substantially equally to the first and second chambers, and then relieving the applied pressure from the first chamber at a greater rate than relieving the applied pressure from the second chamber, thereby pressure unbalancing the piston. - View Dependent Claims (9, 10, 11, 12)
-
Specification