... Q245R, Q345R, 16MnDR, Q370R, 09MnNiDR, 18MnMoNbR, 15MnNiDRHSLA/ High Strength Low Alloy Steel Plate: 1>. Standard: ASTM Grade: A572 Grade 50, A709 Grade 50 ... Q235qC, Q345qC (16Mnq), Q370qC, Q420qCBuilding Structural Steel Plate: GB Q235GJC, Q345GJC, Q390GJC, Q420GJC, Q460GJCHigh Quality Carbon Steel Plate: 1>. ASTM 10252>. GB 20Mn, 50Mn ...