Vibratory response of PWR loop and reactor vessel internals monitored during plant start-up

Preoperational vibration measurement programs have been conducted in pressurized water reactor plants for reactor internals and for primary reactor coolant loop systems. Measurement of vibratory response during preoperational testing provides confirmation of the adequacy of the piping, supports and internals regarding flow-induced vibration and provides a data base for subsequent monitoring programs. The detailed information obtained from direct measurements can support interpretation of measurements obtained from signals monitored during plant operation. This paper describes measurement methods used in preoperational test programs and significant results obtained from reduction and interpretation of the data. 6 refs.