Assessment of environmental effects on fatigue life in LWR nuclear applications

摘要

The rules and requirements provided in Section III of the ASME BOILER and PRESSURE VESSEL CODE has been widely used in the US and in other countries for the design, fabrication, and pressure integrity evaluation of the components for light water-cooled reactor (LWR) type of commercial nuclear power systems. Among its many features, Section III includes procedures for analyzing fatigue damage and possibility of crack formation by fatigue as a result of pressure and temperature cycling during operation. Beginning in the 1950's, Design, Fabrication, and Construction activities related to nuclear power experienced a major increase and the ASME Code increased its scope and activities to keep pace with the increase. Emphasis on the "Design by Analysis" included additional effort on Fatigue analysis with the formation of a Task Group for the determination of allowable fatigue stresses chaired by B. F. Langer. The Task Group collected and analyzed the available fatigue test data and developed curves of allowable fatigue stresses as a function of number of imposed cycles.