| 摘要 |
<p>A Well 5 A well (10) comprsing: (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 positon 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 10 the obstructing member (412,414) from one of the first and second positions to the ote r of the frst sand second positions in response to a change in the signaI 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 1$ the invention have acoustic and/or electromagnetic receivers or transceivers. Figure 1 $ 0 2-2 "N/2b <12 j 20 / Fig. I</p> |
