TWICE-YIELD METHOD FOR ASSESSMENT OF FATIGUE CAUSED BY FAST THERMAL TRANSIENT ACCORDING TO 2007 SECTION VIII-DIVISION 2 OF ASME BPV CODE

摘要

Fatigue analysis is performed for a pipe section subjected to a repeated transient cycle of bulk temperature inside the pipe. No pressure is cycled. Finite element transient heat transfer analysis is performed. The times of the stress reversals are determined by elastic stress analysis. The number of design cycles for cyclic service of the pipe is obtained following the fatigue assessment rules for unwelded locations using the elastic-plastic Twice-Yield method of 2007 Section VIII, Division 2, of ASME Boiler and Pressure Vessel Code. Details for the use of these rules are presented.