1. It can be divided into vessel flange and pipe flange according to the connected parts.
2. It is divided into integral flange, looper flange and threaded flange according to the structure type. Common integral flanges include flat welding flange and butt welding flange.
3. It is divided into threaded connection (screw connection) flange and welding flange according to the connection mode. Low pressure small diameter threaded flange, high pressure and low pressure Welding flanges are used for large diameters.
4. Plate type flat welding flange, neck flat welding flange, neck butt welding flange, socket welding flange, threaded flange,Flange cover, loose flange with neck butt welding ring, loose flange with flat welding ring, ring groove face flange and flange cover, large diameter flat flange, large diameter high neck flange, spectacle blind plate and loose flange with butt welding ring.