Fatigue Analysis in Pressure Vessel Design by Local Strain Approach: Methods and Software Requirements

Abstract

The purpose, methods for the analysis, software requirements, and meaning of the results of the local strain approach are discussed for fatigue evaluation of a pressure vessel or its component designed for cyclic service. Three methods that are consistent with the approach are evaluated: the cycle-by-cycle method and two half-cycle methods, twice-yield and Seeger’s. For the cycle-by-cycle method, the linear kinematic hardening model is identified as the cyclic plasticity model that produces results consistent with the local strain approach. A total equivalent strain range, which is entered on a material strain-life curve to read cycles, is defined for multiaxial stress situations