SEISMIC TEST RESULT (STATIC LOAD TEST) OF THE DYNAMIC FUNCTIONAL DEMAND VALVE FOR NUCLEAR POWER PLANT

The functional maintenance and confirmed acceleration of motor- and air-operated valves in nuclear power plants during an earthquake are regulated in the Japanese seismic design code (JEAC4601 (see Ref. [1])). In the present work, we used a resonant shaking table at the Central Research Institute of the Electric Power Industry (CRIEPI), which is capable of seismic tests at acceleration levels previously unachievable, in seismic tests carried out as high as 20x9.8 m/s(2) (see Ref. [2] to Ref. [8]). On the other hand, JEAC4601 requires the structural evaluation for the seismic critical parts with allowable stress of 1.5-times yield strength (1.5Sy). In this study, in order to confirm the adequacy of the allowable stress, a static load test equivalent to 1.5Sy and more was conducted for the representative valves, namely, the air-operated globe valve and the air-operated butterfly valve. As a result, we confirmed that the required function of the valves was satisfied.