In this paper a comprehensive set of the time-limited ageing analyses for justification of long-term operation of WWER-440/213 type units will be presented. The scope covers mainly fatigue analyses of Safety Class 1 and 2 structures and components, reactor pressure vessel pressurized thermal shock analyses, etc. like in usual practice in case of PWRs. However some specific analyses are required for comprehensive justification of long-term operation, e.g. high cycle fatigue analysis of flow-induced vibration of internal structures of the reactor pressure vessel and internal structures of the steam generators, thermal ageing analysis of Safety Class 1 and 2 components, analysis for material property change of heavy concrete structures of reactor shielding, crack propagation analysis of detected defects, thermal stratification analysis, fatigue analysis of the containment for increased pressure level during integral leak-tightness test. The necessity of the specific analyses is discussed. Arguments are based on the WWER operation experience and engineering considerations. Specific requirements and methodology for routine and specific time-limited ageing analyses and the most important results with explanation of possible consequences will also be presented.

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