| 摘要 |
<p>Disclosed is a remotely operable top drive safety valve assembly having first and second valve elements. An actuator sleeve moves longitudinally on the main body of the top drive safety valve assembly under the influence of an operating arm. When operating the first valve element, a lock plate is preferably installed over the second valve element stem, and an arm is externally fixed to the stem of the first valve element and is disposed in a cutout in the wall of the actuator sleeve. Movement of the actuator sleeve up and down moves the arm, and thereby moves the first valve element between open and closed positions. When operating the second valve element, the arm on the upper valve element stem is removed, a lock plate is preferably installed over the first valve element stem, an arm is installed on the second valve element stem, and a linkage assembly is installed which operationally engages the second valve element stem arm with the actuator sleeve. Longitudinal movement of the actuator sleeve moves the second valve element between open and closed positions via the linkage assembly.</p> |
