Analysis of creep damage in main steam piping components of power stations

The fracture behaviour of components is influenced by damage mechanisms and service conditions. A classification of components with respect to safety risk and availability is possible. According to this classification nondestructive test methods can be chosen in a reasonable manner. Material damage causes a degradation of material properties. For this reason, and because of a lack of calculation methods, a continuation of service in the tertiary creep range cannot be recommended. This is especially important for components for which leakage before fracture cannot be presumed.