Should the flange of 1.0MPa be expressed as PN1.0 or PN10?
After mixing, the trouble is great, and the pressure of 10KG is 100KG.
PN is nominal pressure, Nominal Pressure.In the past, the units behind PN were kg/cm2, PN25, or 25kg/cm2, and the new standard required PN to be MPa. The standards for PN vary from one to another, as follows:HG series flanges clearly specify "flange nominal pressure PN, MPa"",GB/T9124-2000 "steel pipe flange technical conditions" clearly stated: "PN value by bar numerical mark.""JB/T74-94 "technical conditions" said pipe flange was rather baffling "PN value and labeled sample, consistent (according to nominal pressure of 10 times the value of the mark), the" standard "mark not found throughout the sample, and the nominal pressure of all is" PN*MPa (bar)".The above confusion is the root cause of the confusion of the nominal pressure in the society using the "PN" mark. It is suggested to use the unit method to mark the nominal pressure, such as PN**MPa and PN**bar". In selecting the specific meaning of PN, it should be judged according to other information, such as valves, pipes, test pressure, etc..
