| 摘要 |
<p>An hydraulic lock alleviation apparatus (40, 210, 310, 410, 510, 610) alleviates hydraulic lock, for example in a cementing stage tool when a closing plug (107) is employed. The apparatus (40) has a channel (90) for transmitting trapped fluid (which causes a hydraulic lock) from the trapped volume (110) to another volume (113). The channel (90) is blocked by a pressure responsive member (42, 242, 320, 420, 520, 650) which ruptures, moves, breaks, or is punctured to permit trapped fluid to flow from the volume (110) of hydraulic lock. In one embodiment of a stage tool (10) with such an apparatus (40) puncture means (41) is actuable to puncture the pressure responsive member (42). In another embodiment a movable spool (420, 520) is mounted in the channel (490, 590) for actuation to be displaced and thereby to permit the flow of trapped fluid.</p> |
