COMPARISON OF 2 MULTIPLE-HEAT STRESS RUPTURE CORRELATIONS FOR 9CR-1MOSTEEL

This paper compares the only two multiple heat stress rupture correlat ions that use two independent heat-indexing constants: one from Manson and coworkers (MP correlation) and the other from the present authors (RSR correlation). Stress rupture data from literature on 11 heats of a 9Cr-1Mo steel are used for this comparison. The results show that R SR correlation performs better in that (i) it gives lower standard dev iation for error of ht for both individual and multiple heat fits; and (ii) the temperature range over which rupture life extrapolation can be made is extended to lower temperatures for RSR correlation. (C) 199 8 Published by Elsevier Science Ltd. All rights reserved.