Way of closing fluid passage and water hammer-less valve device and water hammer-less closure device

摘要

PROBLEM TO BE SOLVED: To urgently close a fluid path without generating a water hammer and in short time by an extremely simple device and operation.;SOLUTION: This water hammer-less closing device is constituted of an actuator-operated valve interposed on the fluid path, an electropneumatic converter for supplying two-stage actuator operation pressure Pa to the actuator-operated valve, an oscillation sensor attachably/detachably fixed to a duct on the upstream side of the actuator-operated valve, and a tuning box in which an oscillation detection signal Pr detected by the oscillation sensor is inputted and from which a control signal Sc is outputted for controlling the size of step operation pressure Ps' of the two-stage actuator operation pressure Pa to the electropneumatic converter and also the two-stage actuator operation pressure Pa of the step operation pressure Ps' is outputted, by which the oscillation detection signal Pr becomes approximately zero, being outputted from the electropneumatic converter by adjustment of the control signal Sc.;COPYRIGHT: (C)2004,JPO&NCIPI