Introduction - European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard European standard used in petroleum, chemical, power plants, boilers and other industries for the production reactors, heat exchangers, separators, ball cans, oil cans, gas cans, nuclear reactor pressure vessel, boiler drum, liquefied petroleum gas bottles, hydropower high pressure pipes, spiral case and other equipment and components. Implementation of the standards: EN10028 European standard, full name: normalizing weldable fine grain steel. Steel family P275NH, P275NL1, P275NL2, P355N, P355NH, P355NL1, P355NL2, P460NH, P460NL1, P460NL2. Level: room temperature P355N quality level quality level P355NH low quality level P355NL1, P460NL1 special low quality level P355NL2, P460NL2 tensile properties P355N, P355NH, P355NL1, P355NL2 thickness 8-260mm tensile Rm630-450MPa, yield strength: 355-295MPa elongation at break of 21-22% after HIC assessment American Standard steel products HIC test shall be assessed in accordance with EN10229 conducted choose A test solution (PH 3) or B test solution (PH 5) and the corresponding acceptance criteria. HIC test acceptance level: Acceptance Rating Class Class Class I II III CLR% crack length ratio, CTR% crack thickness ratio, CSR% crack sensitivity ratio. Applications - National Yvonne 182 ++ 0366 ++ application P355NH 7703 are: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland, United Kingdom.