Qualification of Electrical Components in Nuclear Power Plants. Management of Ageing

This report reviews R and D results and experiences forming the bases for the preparation of a report on management of ageing. It includes basic information and descriptions of value for persons who work with the questions and some data from investigations of the ageing characteristics of various materials: limit levels, dose-rate effects, activation energies, methods for condition monitoring, etc. This report is restricted to safety related components containing ageing sensitive parts, mainly organic materials (polymers). For components located in the containment, the possibilities of continuous supervision are limited. The accessibility for regular inspections is also limited in many cases. Therefore, the main part of this report deals with the qualification of such components. In addition, some material is given on qualification located outside containment with better possibilities for frequent inspection and supervision. A survey is made of activities, programs and tools for ageing qualification in connection with initial environmental qualification (type testing) as well as after installation (condition monitoring, extension of qualified life through on-going qualification). Tools are also given for supplementary ageing qualification of already installed components