| 摘要 |
<p>An actuator apparatus (16) for actuating a downhole well tool (14) according to which a housing (22) extends in the well and a tool (14) to be actuated is disposed in the housing (22). A drive member (44) is connected to the tool for operating the tool, and an actuator system (36) is disposed in the housing and is normally connected to the drive member (44) for driving the drive member (44) and operating the tool (14). In the event the actuator system (36) fails, an additional actuator systemv (51) is disposed in the housing and is adapted to be connected to the drive member (44) for also driving the drive member and operating the tool (14).</p> |
