Bolt two flat-surface flanges or two raised-surface flanges of the same size together with a gasket (sold separately) to create an access point in a pipe line.

Butt-weld flanges are also known as weld-neck flanges; the flange neck has a beveled end that, when flush to pipe, creates a trough for a strong weld. Socket-connect flanges have an internal stop that supports the pipe when welding and prevents the pipe from sliding all the way through. Slip-on weld flanges have no internal stop; slide a pipe through the flange and weld on both sides. Stub-end flanges are also known as lap-joint flanges; use them with a stub-end straight adapter (not included). The stub-end straight adapter slides into the flange and welds to pipe (not the flange). Since the flange isn’t welded to the pipe, it can be disconnected easily for frequent cleaning and inspecting. Reducing flanges let you transition your piping system to a smaller pipe size; attach to a flange with a larger pipe size but with the same flange dimensions. Cap flanges are also known as blind flanges.

Forged flanges have better strength than cast flanges. Cast flanges are also called MSS flanges.

304 stainless steel flanges offer very good corrosion resistance. 316 stainless steel flanges have excellent corrosion resistance.