A mechanism based approach for remaining life assessment of components exposed to prolonged creep

Today, extensive knowledge-base and data-base are available on popular grades of low alloy steels of Cr-Mo and Cr-Mo-V types. But. what is still lacking is a mechanism based creep life prediction methodology. The present paper attempts to clearly bring out the predictive strengths of two potent parameters: the threshold stress (sigma (H)) and the creep damage tolerance (lambda). The findings are based on systematic study carried out on a Cr-Mo-V main steam pipe line both in the virgin and service exposed conditions. Finally. a life prediction methodology based on sigma (H) and lambda has been proposed for straight pipe lines of the low- alloy ferritic steels.