Clarification on the meaning of a sentence in MR0175-2003

Introduction

This page addresses an inquiry about the meaning of a sentence in Paragraph 4.4 and 10.2.1 of MR0175-2003. The inquiry seeks clarification on whether the statement means there are two qualifying groups, one containing materials with N% + 2 Mo% >30 and the other containing any austenitic stainless steel with 2% Mo minimum, or if there must be a minimum of 2% Mo in the Ni% + 2 Mo% >30 requirement.

Answer

The answer provided explains that answer A2 is correct, and the chemistry requirements are additive. This means that there must be a minimum of 2% Mo in the Ni% + 2 Mo% >30 requirement.

Conclusion

This question pertains to NACE MR0175/ISO 15156-3 A.3.2, Table A.8 and Table A.9, and the reference cited is ISO 15156 Maintenance Panel Inquiry #2003-15.