NACE Bronze Compliance Inquiry

The inquiry relates to the compliance of valve components made of ASTM B148 UNS C95800, C95400, C95500 (body), ASTM B150 UNS C63200 (stem), and ASTM B148 UNS C95800 (ball) with NACE MR0175 for use in SOUR service. The user asks about the chemical, physical, hardness properties, and heat treatment requirements for these materials.

The answer from the ISO 15156 Maintenance Panel states that there are no NACE MR0175 restrictions on the chemistry, hardness, or heat treatment of these materials. However, they may undergo severe weight loss corrosion and be susceptible to hydrogen stress cracking when galvanically coupled to steel. It is the user’s responsibility to determine if qualification of these materials is necessary in the applicable sour service environment, and NACE MR0175/ISO 15156 Part 1 Section 8 provides guidance for material qualification.

NACE MR0175/ISO 15156-1 Clause 8

This inquiry pertains to NACE MR0175/ISO 15156-1 Clause 8.

Reference: ISO 15156 Maintenance Panel Inquiry #2009-12. At OGC Energy, we assist the industry in understanding and implementing NACE MR0175 for copper, aluminum, titanium, and other alloys.