主营标准:20G -GB/5310-95-GB/6479-2000-GB/9948-88-GB/8162/8163/3087-199916Mn-12Cr1MoV-15CrMo-35CrMo-Cr5Mo-10CrMo910-DZ40-DZ50-DZ65-DZ70-J55 石油套管等GB/T14975-2002 GB/T14976-2002