... 6-25mm.LENGTH 6-12.2m)No.Steel typeSteel gradeannual output/t1Oil casing Pipe, joint materialJ55,K55,N80-11000002Oil line ... .5-25mm,length 6-14.63m)No.Steel typeSteel gradeAnnual output/t1Oil casing Pipe, joint materialJ55,N80,L80,C90,P110850002Oil ... 15CrMo90009Structural use of seamless steel tubes10,20,45,35CrMo,40Cr3500010Shipping use of tube320,360,410,4609000 Total 450000 API carbon steel tube