ASME STP-NU-037

The current operating condition allowable stresses provided in ASME Section III, Subsection NH were reviewed for consistency with the criteria used to establish the stress allowables and with the allowable stresses provided in ASME Section II, Part D. It was found that the So values in ASME IIINH were consistent with the S values in ASME II-D for the five materials of interest. However, it was found that 0.80Sr was less than So for some temperatures for four of the materials. Only values for alloy 800H appeared to be consistent with the criteria on which So values are established. With the intent of undertaking a more detailed evaluation of issues related to the allowable stresses in ASME III-NH, the availabilities of databases for the five materials were reviewed and augmented databases were assembled.