Stainless Steel Flange is also a kind of stainless steel pipe fittings. It is a kind of flange with a neck for transition and butt welding connection with round pipes. Butt welding flanges are not easy to deform, have good sealing performance, and are relatively moderate in price. They are widely used in various high-pressure and high-temperature pipelines. 1. The applicable design of flanges and butt welding flanges is different. Flanges are widely used for connecting carbon steel pipelines with a pressure less than 2.5MPa. The sealing surface of the flange can be smooth, concave and convex, and tongue and groove. Among them, smooth flanges are the most widely used, mostly in some medium conditions with relatively mild conditions, such as low-pressure circulating water pipelines. Butt welding flanges are suitable for pipelines with high pressure and high temperature or high pressure and low temperature pipelines. They are also used to transport some pipelines with relatively expensive, flammable and explosive media. Because the sealing of stainless steel butt welding flanges is particularly good and not easy to deform, they can withstand greater pressures and can withstand pressures within 16MPa. 2. The welding methods of flanges and butt-weld flanges are different. Flanges only need to be welded on one side, and do not need to weld the inner port of the pipe and flange connection, while butt-weld flanges need to be welded on both sides, so butt-weld flanges reduce the phenomenon of stress concentration. 3. The quotations of flanges and butt-weld flanges are different. Flanges are cheaper because of their simpler manufacturing technology. Flanges refer to a type of flange that is connected to equipment or pipelines through fillet welds. The structure of flanges is simple and the processing technology is relatively simple. It can be divided into plate flanges and neck flanges. Flanges are widely used in various low-pressure pipelines.