Creep Damage Assessment of Elevated Temperature Piping

Abstract The current ASME Section III, Div. 5 (High Temperature Reactors), design code is very conservative in evaluating creep behavior in piping systems. In addition, the Class B code does not explicitly consider the creep and fatigue damage fraction calculations. A task group has been established to review the existing rules and develop more representative and simplified rules for the design of piping under elevated temperatures. This paper investigates creep damage in piping under elevated temperatures by reviewing some of the relevant methods for calculating piping stress and estimating creep damage. A sample problem with a simplified piping configuration is used to compare these methods and illustrate their steps.