P355GH and P355NH
Thread Content
What does “GH” in P355GH mean? What does “NH” in P355NH mean?
P stands for steel used in pressure vessels; 355 refers to the yield strength. G denotes other properties, while H indicates steel designed for use at high temperatures. Therefore, GH refers to steel designed for high-temperature use with specific other properties required； N denotes normalizing or normalizing and rolling; therefore, NH refers to normalizing steel for high-temperature use, which usually has finer grains and better weldability. This is the naming system according to European standards; the naming method is specified in EN10027. The properties of material P355GH can be found in EN10028-2, while those of P355NH are specified in EN10028-3.