... )1Oil pipeAPI5CT-2005J55,N80,L80,C90,P11060.3~114.3×4.24~16×6100~128002Oil casing PipeAPI5CT-2005J55 ... 2007B,X42,X46,X52,X60,X65,X70,X8060.3~168.3×3.6~22.2×6000~120004Transmission fluid tubeGB/ ... boiler tubeGB5310-199520G,20MnG,25MnG,12Cr1MoVG,15CrMoG,P9160.3~180×4~25×4000~120006lower/medium-pressure boiler ... 6479-200010,20,16Mn,15Mnv,12CrMo,15CrMo60~168.3×3.5~25×4000~120009Structural use of seamless steel ...