Is UNS J91153 NACE MR0175 approved?


In Part 3, A.6.2, Table A.18, under note a) it lists the cast equivalents of the wrought alloys (CA15, CA15M) but under note c) it says cast or wrought S42000 but does not mention the cast equivalent CA40. So, the question is: can I say UNS J91153 is compliant with NACE?


Early versions of MR0175 did not include UNS S42000 in either the cast or wrought form but S41000 and the cast alloys CA15 and CA15M were included. Wrought S42000 was balloted in 1994. When ISO 15156 was being developed, the statement including “cast or wrought S42000” was added. There was previously a cast version of S42000 (J91201) but that has been withdrawn from the UNS numbering system. Since a cast version of S42000 was never balloted and the casting alloy your inquiry specifies (J91153) is chemically different from S42000, it is not correct to claim that J91153 meets ISO 15156-3. A ballot would be required to change this. See ISO 15156-3 Annex B for CRA testing and balloting guidance. The ballot form is available on the ISO Web site www.iso.org/iso15156maintenance in the document “Introduction to ISO 15156 Maintenance Activities” Annex C.
A.6.2, Table A.18 and Table A.23

This question is in relation to NACE MR0175/ISO 15156-3 A.6.2 Table A.18

Reference: ISO 15156 Maintenance Panel Inquiry #2011-09

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