AGING ASSESSMENT AND PLANT LIFE MANAGEMENT

The safety standard of a nuclear power plant at the time of initial startup must be assured throughout the plant's entire lifetime. The original design life should be systematically reevaluated in the light of new findings and developments in the field of safety. Reevaluation results can also be useful for preventive maintenance and prolongation of the planned or licensed service life. Moreover, they form the basis of decisions regarding technical upgradings and backfittings and are useful for optimization of plant availability and in the case of power uprating. Measures which provide prompt identification of aging of light water reactor components due to deterioration of materials and their properties (eg., fatigue, local corrosion, erosion corrosion, neutron irradiation) are presented in this paper.