Patent ID: 8413956
Filing Date: 2013-04-09
Classification: C10B,F16K,Y10T

Abstract:
1. A double-disc gate valve, the shut off or valve discs of which are displaceable from an open position into a closed position and vice versa by means of an actuator rod, there being associated with the actuator rod a locking device by means of which the valve discs, together with the actuator rod, are fixable in the closed position, wherein the locking device is movable in the longitudinal direction of the actuator rod relative thereto from an unlocking position into a locking position and vice versa, the locking position being variable in dependence upon the closed position of the valve with predetermined maximum pressing force of the valve discs against associated valve housing sealing seats: wherein the locking device comprises a trapezoidally threaded portion arranged on the actuator rod and a locking nut which is arranged to be screwed onto the actuator rod, wherein in the closed position of the valve the locking nut is capable of being screwed onto the threaded portion as far as a stop which is arranged in fixed position with respect to the actuator rod for locking thereof, wherein the locking nut is capable of being screwed onto and unscrewed from the threaded portion of the actuator rod by means of one of an electric, pneumatic and hydraulic drive means, and wherein the locking nut is arranged inside a gear housing, which is displaceably mounted parallel to the actuator rod, and is movable therewith in the longitudinal direction.