Lock-out valve with controlled restart

摘要

A lock-out valve is designed to direct pressure fluid to an operational port and system, and to exhaust such pressure for purposes of repair or reconstruction of a valve controlled system. The valve may be quickly moved to the exhaust phase by a manual stroke overriding threads between two concentric parts. However, reverse motion of the valve to re-establish pressure to the operational port can only be accomplished by a turning action on the manual actuator. This insures a slow return of pressure to the system and a slow start up so that the controlled system can be safely and properly reset. The thread design is such that the motion in one direction will override the threads but prevent reverse action except by turning.