... inch WT:6mm to 30mm standard:GB,ASTM,JIS,DIN,API5L,API5CT steel grade:ASTM A106,A53,X42,X52,X60,PSL1 SIZETHICKNESS(mm ... )STEEL GRADESTANDARD8”6-15 ASTM A53,A283-D,A106,A333; JISG3456,G3454 ... ,G3455; ST37,ST42,ST45-8,ST52; GB Q235,20#,10#,45#,16Mn,Q345 ASTM, JIS, DIN ...