| 摘要 |
<p>A well (10) comprising: (a) a safety mechanism (16,25), the safety mechanism comprising: (i) an obstructing member (412,414) moveable between a first position where fluid flow is permitted, and a second position where fluid flow is restricted; (ii) a movement mechanism (416,418); (iii) and a wireless receiver (360), adapted to receive a wireless signal; wherein the movement mechanism (416,418) is operable to move the obstructing member (412,414) from one of the first and second positions to the other of the first and second positions in response to a change in the signal being received by the wireless receiver (360); (b) sensors to detect a parameter in the well (10), in the vicinity of the safety mechanism (16,25); wherein a sensor is provided above and a sensor is provided below the safety mechanism (16,25). Embodiments of the invention have acoustic and/or electromagnetic receivers or transceivers.</p> |
