Manufacturers & Suppliers of ASTM B564 Hastelloy B2 WNRF Weldneck Flange, 1/2\" WNRF Flanges Sch 40, ASME B16.5 Class 400# Weldneck Flange, ASME SB564 Alloy B2 WNRF Welding Neck Flanges, ANSI B16.5 WNRF, DIN 2.4617 Welding Flange, UNS N10665 WNRF Flange.