How a Knowledge Data Base Assists the Process of Aging Management

Abstract

The process of aging management in a nuclear power plant requires collaborative work of different departments. In this process information has to be gathered and evaluated systematically. At the beginning of the process it is important to classify all systems, structures and components (SSCs) into 3 categories of descending importance concerning safety where only the first two categories have to be considered for aging management. Basic information on the material and dimensions, operational parameters, quality status, analysis reports and relevant degradation mechanisms is stored in the data base for all SSCs of category 1 and 2. While a nuclear power plant is in service numerous events may occur which are related to aging and may have an influence on the quality of SSCs. Relevant events may be malfunction messages, maintenance results, operational experience, results of surveillance or events in external installations. It is important to evaluate these events concerning the aspect of aging and to decide which measures are required to prevent unexpected events of the same kind in the future. In some cases the new experience has to be assigned to comparable SSCs. These evaluations, the definition of measures and the tracking of their effectiveness have to be done by an aging management team that meets regularly every 3 months. The knowledge data base supports the application of the PDCA cycle and provides an overview and fast access to all quality documents related to each SSC including surveillance measures and results. It simplifies the generation of annual status reports which are valuable quality documents that reveal the effectiveness of aging management. Finally the procedure can be extended to SSCs which are important for the availability of the plant and thus take a step forward from aging management to plant life management.