... ,JIS.etc 2-material:carbon steel, alloy steel et ASTM 20# seamless steel pipe for liquid transportation SpecificationsChina StandardSteel GradeStandardseamless steel tubesand pipesfor structural purposeGB ... BoilersGB3087-199910, 20ASTM A179, ASTM A192 ASTM SA179,SA192, BS3059Seamless Steel Tubes for high pressure --Chemical fertilizer equipmentGB6479-8610, 20G, Q345, Q390 ...