Prediction of creep failure life of internally pressurised thick walled CrMoV pipes

Abstract

Creep continuum damage finite element analyses were performed for a typical internally pressurised main steam thick-sectioned plain pipe geometry subjected to a range of axial loading conditions. The creep failure lives, for a range of loading levels, were obtained. The stress distributions showed the presence of a skeletal point or representative rupture stress. Life estimates were made using alternative stress forms and these were compared with the failure lives predicted using continuum damage analyses. For the particular ferritic material properties used in the analyses, the failure life of the pipe can be obtained accurately using the steady-state reference rupture stress or the skeletal point rupture stress.