Inconel 625 (UNS N06625) for Sour Service Materials: Compliance with NACE MR0175/ISO 15156

Manufacturing sour service materials with Inconel 625 (UNS N06625) requires compliance with ANSI/NACE MR0175/ISO 15156. This article discusses specific metallurgical requirements for Inconel 625 as mandated by NACE MR0175, including metallurgical conditions and hardness.

Annealing Requirements for Alloy 625

NACE MR0175 mandates that Alloy 625 must be in an annealed condition. However, suppliers may offer Alloy 625 quenched off the hammer instead. The maintenance panel was consulted on this issue.

The inquiry asks whether Alloy N06625 (Alias – Alloy 625) would meet the requirements of NACE MR0175/ISO 15156-3 Table A.13 if the forged material was quenched off the hammer rather than undergoing separate annealing.

The response states that it is the manufacturer’s responsibility to determine whether Alloy 625 is annealed under these conditions, rather than the role of the MP to answer metallurgical questions. If Alloy 625 is annealed, then it meets Table A.13 requirements.

NACE MR0175 Hardness Requirement for Inconel 625

NACE MR0175 / ISO 15156 Part 3 Clause A.4 provides details of material requirements for solid solution nickel alloys, including Inconel 625 (UNS N06625).

At OGC ENERGY, we assist manufacturers in determining the optimal route for forging and annealing Alloy 625. We also help users review material test reports (MTRs) and manufacturing documentation to ensure compliance with NACE MR0175 and other regulatory requirements. Speak to our team today for assistance!