Abstract
On WWER type reactors reactor pressure vessel (RPV) integrity should be assured during operational life-time since there is no any real measures which could mitigate consequences of RPV rupture. One of the possible ways of RPV rupture is cold overpressure phenomena. Evaluation of loads/impact on RPV depends on plant condition and initiating events which could lead to cold overpressure. The main characterized parameters of cold overpressure phenomena are high pressure and low temperature. Selection of initiating events which could lead to cold overpressure during full power operation and hot shutdown and identification of accidental scenarios using probabilistic methods are presented in this paper.
