| 摘要 |
A method of actuating multiple valves in a well can include applying one or more pressure cycles to the valves without causing actuation of any of the valves, and then reducing pressure applied to the valves, thereby resetting a pressure cycle-responsive actuator of each valve. A pressure cycle-operated valve for use in a well can include a closure member, a piston which displaces in response to pressure applied to the valve, and a ratchet mechanism which controls relative displacement between the piston and the closure member. The ratchet mechanism may permit relative displacement while one or more pressure cycles are applied to the valve, and the ratchet mechanism may prevent relative displacement in response to a pressure sequence of: a) a reduction in pressure applied to the valve, b) a predetermined number of pressure cycles applied to the valve, and c) an increase in pressure applied to the valve. |
