| 摘要 |
PURPOSE:To diagnose with sensitivity and accuracy whether or not there is a sign of slight trouble of a stop valve unit, by providing a sensor for detecting the opening and closing motion of the valve element of the stop valve unit and by processing the output signal of the sensor to judge whether the opening and closing motion is proper or not. CONSTITUTION:A main steam stop valve unit has a valve portion A which is opened and closed through a valve spindle 6 by a driving portion C made of a hydraulic cylinder. A position sensor 53 for detecting the motion of the valve spindle and the valve 4 of the valve unit and limit switches 51, 52 for detecting the fully open and entirely closed positions of the valve 4 are provided. The outputs of these detectors 51-53 are entered into a microcomputer not shown in the drawing. The electric output signal of the sensor 53 is stored in the microcomputer at every prescribed sampling period. Every time that the electric signal of the sensor 53 is received, it is compared with the preceding signal to judge and indicate whether the opening and closing action of the valve unit is proper not or not. |
