... Steel typeSteel gradeannual output/t1Oil casing Pipe, joint materialJ55,K55,N80-11000002Oil line pipe B,X42~X60(L245~L415)50003high ... fluid tube10#,20#,Q295,Q345,Q390300006Structural use of seamless steel tubes10#~45#,40Mn2,35Cr,35CrMo500007Hydraulic pillar tube, ... equipment10,20,16Mn,15Mnv,12CrMo,15CrMo90009Structural use of seamless steel tubes10,20,45,35CrMo,40Cr3500010Shipping use of ...