What is the Inconel 625 ASME code?
Inconel 625 alloy, UNS N06625, has a nominal composition of 60Ni–22Cr–9Mo–3.5Cb. Materials made from Inconel 625 alloy are widely used in projects designed to the ASME Boiler and Pressure Vessel Code. They can be supplied in the solution annealed (Grade 2) or annealed (Grade 1) condition. Its product forms are plates, sheets, strips per ASME SB-443/ ASTM B443; seamless pipes and tubes per ASME SB-444/ ASTM B444; bars per ASME SB-446/ ASTM B446; forgings per ASME SB-564/ ASTM B564, welded pipes per ASME SB-705/ ASTM B705; welded tubes per ASME SB-704/ ASTM B-704; seamless and welded fittings per ASME SB-366/ ASTM B366.
It should be noted that the impact strength of 625 alloy in the annealed condition is severely degraded at room temperature after exposure to temperatures ranging from 1000°F to 1400°F. In general, the applicability and maximum temperature limits of Inconel 625 alloy in different product forms and conditions are as follows:
All the above 625 alloy product forms (whether solution annealed or annealed) can be used in ASME Section I with a maximum temperature limit of 1100°F, ASME Section VIII-1 Section 1 with a maximum temperature limit of 1600°F, and Section XII with a maximum temperature limit of 650°F.
In some cases, only the material in the annealed condition (UNS N06625) can be used in ASME Section III with a maximum temperature limit of 800°F; Inconel 625 alloy rods can be used as bolting materials in ASME Section VIII Division 1, Section VIII Division 2, and Section XII with maximum temperature limits of 1200°F, 800°F, and 650°F, respectively.
