Flanges

A flange must match its mating flange in standard, pressure class, size and facing. Confirm the standard (such as ASME B16.5), the class (150, 300, 600 and so on), the type (weld neck, slip-on, socket weld, threaded, blind, lap joint), the face (raised or flat) and the material. Weld-neck flanges are usually chosen for demanding services; slip-on flanges are easier to fit on lower-pressure lines. Remember to order the matching gaskets and bolting.