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 結(jié)構(gòu)用無(wú)縫鋼管
 Seamless steel tubes for structural purposes

 GB/T 8162
 10, 20, 35, 45,
 40Cr, 35CrMo

 輸送流體用無(wú)縫鋼管
 Seamless steel tubes for liquid service

 GB/T 8163
 10, 20, Q345B

 低中壓鍋爐用無(wú)縫鋼管
 Seamless steel tubes for low and medium pressure

 GB3087
 10, 20

 高壓鍋爐用無(wú)縫鋼管
 Seamless steel tubes and for high pressure boiler

 GB5310
 20G, 12CrMoG,
 15CrMoG, 15MoG,
 12Cr2MoG, 20MoG,
 12Cr1MoVG

 船舶用碳素?zé)o縫鋼管
 Carbon carbon — manganese steel seamless tubes and pipes for ship

 GB/T 5312
 C10, C20

 化肥設(shè)備用高壓無(wú)縫鋼管
 Seamless steel tubes for high pressure

 GB6479
 10, 20, 16Mn
 12CrMo, 15CrMo

 石油裂化用無(wú)縫鋼管
 Seamless steel tubes for petroleum cracking

 GB9948
 10, 20,
 12GrMo, 15GrMo

 冷拔或冷軋精密無(wú)縫鋼管
 Cold — drawn or cold — rolled precision seamless steel tubes

 GB/T3639
 10,20,35,45
 Q345B