| 摘要 |
<p>Tool and method for isolating a wellbore zone comprising a housing having a flapper member 125 moved to a closed position by rotation. A flapper latch assembly 300 is positioned to engage with end 145 of the first flapper member and lock it in the closed position. The latch 300 moves from an unlocked position (fig 5) to a locked position (fig 4) when the flapper and latch move together relative to the housing to a recess 340 in the housing, the latch locks when the latch moves into the recess. The latch assembly can include a pin member 325 and a biasing member and may be biased in the locked position, a release mechanism 310 can be included to move the first flapper member from the closed to the open position, the release mechanism may be a shear member</p> |
