| 摘要 |
<p>A remote control downhole valve (200) includes a controller (224) having receiver means (232), comparing means (226) and control signal generator means (236) , and a valve element (208) movable by an actuator between an open and a closed position. Pressure change signals are introduced into a column of fluid standing in the well, including a command signal having at least one high level pressure change. The high level pressure change includes a change from a first value to a second value, with the second value being at least 1,000 psi (6.89 MPa) above hydrostatic pressure of the column of fluid in the well, and with pressure being maintained at the second value for an interval of time corresponding to information stored in the control system of the downhole valve. <IMAGE></p> |
