Methods and results of probabilistic analysis of leaks and breaks of NPP equipment elements

The paper presents a brief description of a procedure for calculation of the probability of leaks and breaks onset in the high pressure vessel such as the pipes, reactor vessels, steam generators etc., developed at the RRC 'Kurchatov Institute'. The procedure and the code MAVR-2.1 created on its basis can be used for the analysis of a wide spectrum of operation, technological parameters for the strength reliability and service of the nuclear power plant. The procedure is based on the mathematical modelling of the kinetics of defect development with allowance for the spread in the data on the initial size, concentration and the rate of subcritical growth as well as on the probabilistic distribution of defect control and repair, heat, stress and radiation loads