Flange, also known as a flanged disk or rim, is a component used for connecting pipes to each other, or between equipment进出口. Flange joints, or flange connections, refer to the detachable connections formed by the combination of flanges, gaskets, and bolts. Pipeline flanges are those used in piping systems, and equipment flanges are the进出口 flanges on equipment. Flanges have holes and bolts are used to tightly secure the two flanges. Gaskets are used to seal between the flanges. Flanges come in threaded (screwed) connections,焊接 flanges, and clamp flanges. Flanges are always used in pairs; low-pressure pipelines can use threaded flanges, while those above 4 kg of pressure use焊接 flanges.