... .2m) No.Steel typeSteel gradeannual output/t1Oil casing Pipe, joint materialJ55,K55,N80-11000002Oil line pipeB,X42~X60(L245~L415)50003high-pressure boiler ... .63m) No.Steel typeSteel gradeAnnual output/t1Oil casing Pipe, joint materialJ55,N80,L80,C90,P110850002Oil casing Pipe, joint materialJ55,N80,L80-1,C90,T95 ... ,40Cr3500010Shipping use of tube320,360,410,4609000 Total 450000component oil line pipe