[MW:12967] RE: 12957] NACE compliance for sour service

Hi Hafiz,

22 HRC hardness requirements is one of the requirements of NACE for materials required form sour service.In the industry this is considered to be major one and generally often talked about.

You may please refer-- ANSI/NICE MR0175/ISO 15156-2:2009(E). The vendor has to fulfill all the applicable requirements of Annex -A. Though described as normative, this chapter gives all the detailed requirements.To the best of my knowledge the following clauses( which may be a part of overall requirements) shall be met by the supplier:-

A.2.1.2 Parent metal composition, heat treatment and hardness
A.2.1.3 Carbon steels acceptable with revised or additional restrictions
A.2.1.4 Welding
A.2.1.6 Cold deformation and thermal stress relief
A.2.1.9 Identification stamping

If the vendors supply products with maximum 22 HRC (237BHN or 248 VHN) hardness then and the above requirements then they're within the requirements of MR-0175. But note if there's requirements of 22HRC max of hardness after welding and PWHT(as required), then staring with with a base metal hardness closer to 22 HRC could be troublesome. One may have to do a trade off on the ITB specification requirement ,i.e 200 BHN Max vs. 237 BHN as offered by the suppliers.

Appreciate your further feedbak on this topic.

Thanks.

Pradip Goswami,P.Eng.IWE

Welding & Metallurgical Specialist & Consultant

Ontario,Canada.

Email-pgoswami@sympatico.ca,

pgoswami@quickclic.net

Now my questions is;
1) What are the minimum requirements for the material to be NACE Complied? (HIC is not required clarified by client)
2) Can we accept 22HRC hardness as per NACE MR-0175

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Hafiz Ali Alvi
Sent: Sunday, November 13, 2011 1:43 AM
To: materials-welding@googlegroups.com
Subject: [MW:12957] NACE compliance for sour service

Hello All,

My question is about NACE compliance for sour service. As per ITB documents two different requirements has been mentioned;

1) Pipes, fittings and forgings in sour service shall be only NACE compliant.
2) Hardness of Carbon Steel material shall not exceed 200BHN.

Procurement send inquiry to different vendor for piping items and vendor's respond that they will comply with NACE MR-0175 (Hardness Only). Also as per NACE Max. hardness limit is 237 BHN(22HRC) which is higher than 200BHN.

Now my questions is;
1) What are the minimum requirements for the material to be NACE Complied? (HIC is not required clarified by cleint)
2) Can we accept 22HRC hardness as per NACE MR-0175.

Regards.

Hafiz Ali Alvi
Piping Material Engineer
JGULF

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