| 摘要 |
A downhole isolation valve includes (a) a valve housing having a central flow passage, and an internal circular valve seat; (b) a split ball valve comprising two partial spherical portions disposed within the flow passage, each portion rotatable on a transverse axis between an open position, and a closed position wherein the two partial spheres mate with each to form a hemispherical valve seated on the valve seat, which blocks the central flow passage; (c) a sliding member disposed within the valve housing, and moveable between a closed position and an open position by a pressure differential between an upper hydraulic chamber and a lower hydraulic chamber; (d) a vertical actuator engaging the sliding member; and(e) a rotational drive which translates longitudinal movement of the vertical actuator to rotational movement which opens or closes the split ball valve. |
