The reason why flange is called "flange" is because its name comes from the transliteration of the English word "flange". It was first proposed by an Englishman named Elchat in 1809, who also proposed the method of casting flanges. Although flanges were not widely used in the initial period, by the early 20th century, with the increasing demand for various mechanical equipment and pipeline connections, flanges began to be widely used in these fields. In addition, flanges are also known as flange convex discs or convex discs. They are a type of disc-shaped component, usually used in pairs, mainly for the connection between pipelines and valves, pipelines and pipelines, and pipelines and equipment, playing a sealing role. Therefore, the name of flange comes directly from its English original word "flange" and is transmitted into Chinese through transliteration.