Elaboration and Introduction of the Methodics of Non-Destructive Inspection (Control) of Physical-Mechanical Properties of NPP Pressure Vessels

Resource of reactor with PWR is defined, in the first instance, by foundation of integrity of the third physical barrier of safety. The third physical barrier of safety provides a reliable keeping of the coolant in the boundaries of NPP primary circuit. More than thirty year history shows, that reactor vessel is a weak spot in this barrier, the metal of the pressure vessel is subjected to intensive irradiation. The mechanism of operational damage of pressure vessel steel is represented in Fig. 1. This article describes the works, which were conducted by VNIIAES during the last years in the field of elaboration of specimen-free methods and means of inspection (control) of physical-mechanical properties of pressure vessels welds metal of NPPs with PWR. On the base of analysis of that factors, which exercise the most substantial influence on the irradiation embrittlement of pressure vessel materials and on the base of distribution of these factors by degree of significance, there were selected the most appropriate specimen-free methods of inspection: kinetic indentation and kinetic magnetising. It was presented the description of the specimen-free methods, devices and of the results of laboratory measurements, and also the description of the manufacturing procedure and the procedure of certification of the methods on full-scale slabs from WWER-1000 pressure vessel. In the article also is described the example of using of the specimen-free methodics by full-scale inspection (control) of the metal of reactor internal components and of pressure vessel of WWER-1000 of Rostov NPP Unit 1.