Investigation of T-book Reliability Data Used In Probabilistic Safety Assessments: Comparison between Sites, Reactors and Types

摘要

The T-book version 6 is a collection of component reliability data for twelve Swedish and two Finnish nuclear power plants. The data are based on failure reports from these power plants. An investigation is performed of these data with the objective to study the component reliability data in the T-book version 6 in detail, with the intention to find similarities, differences, deviations etc. between different types of reactors, reactors from different generations and sites. Data from all the data tables in the T-book were entered in the templates creating one set for each table, thus providing insights on each data table, corresponding to a specific component type and failure mode, the whole set of filled templates providing a good overview of all the data. The relative standard deviation calculated for each table for values from different plants shows the spread of data around an average value and allowing data for different failure modes to be compared. The templates also present the tables in the T-book as diagrams making it easy to find the components that have very heterogeneous values for the different reactors. Results from the investigation give insights on the correlation of values from different plants with regard to factors like reactor type (BWR versus PWR), sites, NPP age (generations) and the spread of reliability data in different groups of components. Insights from this investigation are presented and discussed.