A flange is a metal component used to connect or secure pipes, equipment, etc. It is usually in the shape of a disc, with holes on the surface for connecting bolts, and through the fastening of bolts, the two flanges are firmly connected to realize the connection of pipes or equipment. The length of a flange refers to the axial length in its overall dimensions, including the diameter of the flange, the protrusion of the connecting bolt, and other ancillary structures. Flanges designed with a length of 200 mm need to be selected according to the specific application to ensure that the connection is strong, stable and has good sealing. In the petroleum, chemical, electric power and other industries, flange connection is widely used and is an important component for pipeline and equipment connection.