In addition to this material, butt weld flanges are also stainless steel. Flanges are made of ASTM A182, F304, 316L, 347H, 310S, ASME B16 5 and finished with duplex steel.
The duplex steel material of UNS S31803 is also in use. In addition to stainless steel, butt weld flanges are available in various other materials such as carbon alloys and nickel. Nickel alloy butt weld flanges are available for Inconel 600 and 625, Hastelloy C22, C276 and other such materials.