... manufacture 1 standard: API,BS, JIS, GB, DIN, ASTM 2 grade: X42,X46,X52,X56,X60,X65,X70.... seamless ... Material: A106 Gr A,B,A53 Gr B,ASTM A179,A106GrB,ASTM .A53GrB St42 St45 Tp321 Tp315 mechanicalproperties StandardGradeTensile Strength ... -758386-544≥18≥40normalizingX60517-758414-565≥18≥40normalizingChemical composition StandardGradeChemical composition limits,%CSiMnPSTiAPI 5LB≤0.24-≤1.20≤0. ...