The GB713 standard specifies the order content, grade and representation of the steel for boiler and pressure vessel, size, shape, weight and tolerances, technical requirements, test methods, inspection rules, packaging, marking and quality instructions. This standard applies to the boiler and the temperature of the pressure vessel pressure components with a thickness of 3 ~ 250mm steel plate.GB713 standard main steel grade:GB713 12Cr1MoVR,12Cr2Mo1R,13MnNiMoR,15CrMoR,Q245R,Q345R and so on.