SGS certificate High quality Carbon steel welded pipe Q195 A283 Q215 Q235 SS400 Q345for mineral slurry,building construction transmission of petroleum and natural gas,water1. Standard: GB/T 3091-2001, GB/T3087,BS1387-1985, DIN EN10025, EN10219, ASTM SCH40/SCH80,ASTM-A532. Grade: 10#-45#, A53(A,B)-A369,Q195-Q345, S235JR, S275JR, S355JR3. OD:..