| 摘要 |
A downhole bypass valve comprises a tubular body including a side port and a sleeve axially movably mounted in the body and normally biased to a closed position to close the side port. An activating device is configured to be pumped or dropped into the body to engage the sleeve and permit movement of the sleeve to an open position and open the side port. A latch has a part in the body and a part in the activating device, the parts of the latch configured to engage and retain the sleeve in the open position. The activating device is further operable to disengage from and translate through the sleeve and the parts of the latch are further operable to disengage and permit the sleeve to return to the closed position. |
