... tube2.OD:8mm-110mm;WT:1mm-14mm3.Standard: GB/T8162 , GB/T8163 ,ASTM A53 ,ASTM A106 ,DIN1629 , ... API 5L 4.Steel grade: GB/T8162 , GB/T8163:10#, 20#, 35#, 45#, 16MN(Q345B) ... /Ground4. Process: EAF+LF+VD+ Forged+ Heat Treatment (Annealed, Normalized, Q+T) 5.Certification: ISO9001-2000 6. Inspection ... sight Note:1. According to national standard (GB)for our products, if not, supply according ...