... fluid tube10#,20#,Q295,Q345,Q390300006Structural use of seamless steel tubes10#~45#,40Mn2,35Cr,35CrMo500007Hydraulic pillar tube, ... typeSteel gradeAnnual output/t1Oil casing Pipe, joint materialJ55,N80,L80,C90,P110850002Oil casing Pipe, joint materialJ55,N80,L80- ... equipment10,20,16Mn,15Mnv,12CrMo,15CrMo90009Structural use of seamless steel tubes10,20,45,35CrMo,40Cr3500010Shipping use of ...