What are the NACE MR0175 limits for Nitronic 50 (UNS S20910)?
The NACE MR0175 received the inquiry shown below, if you need technical support on Nitronic 50 (UNS S20910) get in touch with us.
Our customer does not understand the NACE the same way as we do regarding the use of Nitronic 50 “hot worked” when applying Table A.3 (see document attached). It is only a matter of interpretation of the NACE and we are convinced that on the contrary Nitronic 50 should be used “hot worked” and can be used “cold worked” if preceded by an annealed treatment. The only way to convince them that they can use Nitronic 50 hot worked for their application, would be if we have someone from NACE who would certify that our interpretation above is correct.
The following interpretation can be given for use of UNS S20910:
“The note in Table A.3 permits the use of UNS S20910 in the solution annealed and cold worked condition provided that the hardness does not exceed 35 HRC. The solution annealed condition is also acceptable.
Also, refer to Table A.2 which permits use of listed materials for any equipment or components. This Table contains the following note “S20910 is acceptable in the annealed or hot rolled (hot/cold worked) condition at a maximum hardness of 35 HRC”.
If your question is of whether UNS S20910 is acceptable in hot worked conditions for the limits listed in Table A.3, we would ask you to re-phrase your inquiry to specifically ask for this. The standard is not using expressions such as “should be used” or “can be used” for limits given in the tables.
Note that the answer to this is not clearly given in the standard and we will need some time to discuss the answer to this with the Maintenance Panel for the ISO 15156 / NACE MR0175.
This question is in relation to NACE MR0175/ISO 15156-3 Table A.3
Reference: ISO 15156 Maintenance Panel Inquiry #2014-09