American standard pressure is weighing (class 150LB refers to 150 pounds pressure, equivalent to the pressure of PN2.0), followed by different specifications: American standard flanges are called ASMEB16.5 and ASMEB16.47Seriea  A and B  by inch. Flange is also called flange or flange. Flanges are parts that connect pipes to pipes and valves and are connected to the end of pipes. There are holes in the flange and bolts make the flanges close together.

According to the 2009 edition of the Ministry of Chemical Industry Standard, the national standard flange is divided into the European standard system and the American standard system, which are further revised and formulated by referring to the two systems of European and American flange respectively. The European system has nothing to do with ASME flange. The flanges are sealed with gaskets. Flanges are divided into threaded joints (threaded joints) flanges and welded flanges and jacket flanges. Pipeline flange refers to the detachable connection of flange, gasket and bolt as a group of combined sealing structures. Pipeline flange refers to the flange used in piping equipment, and the flange used in equipment refers to the import and export flange of equipment.

American system is the same as ASME flange, but there are still a lot of different data sizes, such as sealing surface, flange neck and so on. In the 2009 edition, American flange and American flange can hardly be referred to each other because of the individual pound class. There are holes in the flange, and the bolts connect the flanges tightly. The flanges are sealed with gaskets. Flange is divided into threaded connection (screw connection) flange, welding flange and clamp flange. Flanges are used in pairs. Wire-jointed flanges can be used in low-pressure pipelines, and welding flanges can be used under pressure of more than four kilograms. A gasket is added between the two flanges and then bolted. Flanges under different pressures have different thicknesses and bolts. Pumps and valves, when connected to pipes, parts of these equipment are also made into corresponding flange shapes, also known as flange connections.