LR-0 and questions of reliability of pressurized water reactor power plants

An analysis is made of the reliability of PWR nuclear power plants based on more than 20 years operating experience. The criteria are given of failure analysis according to the distribution of failures and their frequency in different components and systems, the problems are presented which are related to obtaining primary information on failures and to the establishment of suitable databanks, as are the individual causes and consequences of failures according to significance, including the dependence of the reliability of nuclear power plants on age. Research work is described which by the analysis of physical processes and using experiments carried out on LR-0 contributes to the clarification of mechanisms and causes of failures of PWR fuel elements and vessels. Research is also dealt with oriented to the evaluation of the statistical probability of failures and their classification with the aim of developing a complex programme of controlled reliability. (author)