... (1/8''-40'') Wall Thickness 1.2mm-39mm Grade 10#,20#,45#,16Mn,27SiMn,12Cr1MoV,Q235, ST42,ST52,A106-a ... SpecificationsChina StandardSteel GradeStandardseamless steel tubesand pipesfor structural purposeGB/T8162-199910, 20, 35, 45, 40Mn2, 45Mn2, 27SiMn, 20Cr, 40Cr, 20CrMo, ... 2-1997 ASTM A161-94Seamless steel tubesfor petroleum crackingGB9948-8610, 20, 12CrMo, 15CrMo, 1Cr2Mo, 1Cr5Mo, JIS G3441-1988 China ...