A weld neck flange (also known as a high-hub flange and tapered hub flange[2]) is a type of flange. There are two designs. The regular type is used with pipes. The long type is unsuitable for pipes and is used in a process plant. A weld neck flange consists of a circular fitting with a protruding rim around the circumference. Generally machined from a forging, these flanges are typically butt welded to a pipe. The rim has a series of drilled holes that permit the flange to be affixed to another flange with bolts
