ChinaFlatFlangeFactory The main characteristics of the flange are the connection mode and sealing form. The main influencing parameter is the pipe pressure (different media affect the selection of materials). Generally speaking: Low pressure system (pn2.5mpa) adopts flat welding or plate flange; Common raised face (RF) seal, medium pressure system (2.5-64mpa) adopts butt welding flange; RF or concave convex surface (fm/m) seal, high-pressure system (above 10.0MPa), usually adopts butt welding flange and ladder groove (RJ) seal; In low-pressure stainless steel system, loose flange or loose ring flange is sometimes used to save cost and facilitate maintenance. Standard classification of flanges At present, there are many flange standards, including GB (national standard), JB (standard of Ministry of machinery), Hg (standard of Ministry of chemical industry) in China, ANSI (American Standard), JIS (Japanese standard), DIN (German standard) in foreign countries. However, the standards currently used are divided into two categories: European system based on DIN standards (including DIN, GB, JB, hg20592); American system based on ANSI standards (including ANSI, GB and hg20615). These two types of flanges can be distinguished by the identification indicating the pressure class of the flange. (JIS standard is the standard of another type of system, not belonging to this category)ChinaFlatFlangeFactory website:http://www.sy-exports.net/flat-flange/