Integral flanges are widely used in the design of valves and pumps, and are often encountered in piping design. Therefore, in order to ensure the integrity of the standard and facilitate the application of design, manufacturing and use departments, this description adds integral flanges. species. The applicable pressure range and nominal diameter of the integral flange are PN0.6~25.0MPa and DN10~2000 according to ISO7005-1 and DIN flange standards. There are five kinds of tongue and groove surfaces and ring connection surfaces.