Flanges are a kind of disc-shaped parts, which are most commonly used in pipeline engineering. Flanges are used in pairs. In pipeline engineering, flanges are mainly used to connect pipelines. In the pipes that need to be connected, a flange can be installed. Wire-connecting flanges can be used for low-pressure pipes, and welding flanges can be used for pressures of more than 4 kg. Add a sealing point between the two flanges, and then tighten it with bolts. Flanges of different pressures have different thicknesses and different bolts. When water pumps and valves are connected to pipes, parts of these equipment are also made into corresponding flange shapes, also known as flange connections. All connecting parts that are bolted at the periphery of two planes and closed at the same time are generally called "flange". For example, the connection of ventilation ducts, this type of part can be called "flange parts". However, this connection is only a part of the equipment. For example, the connection between the flange and the water pump is not easy to call the water pump "flange parts". Smaller ones, such as valves, can be called "flange parts". 

 The use of flange 

 The flange is used for positioning. For example, there is an installation method of the cylinder called flange installation, which is like four symmetrical holes around a cuboid, with a large hole in the middle that is the same as the outer diameter of the cylinder. This cuboid is welded between them and fixed together in other ways. The cylinder and the connection between the cylinder and other things is around the cuboid. Four holes, this cuboid connection can be called the method orchid.