Steel Bar, Cold Drawn Steel Bar, Carbon Steel Rod manufacturer / supplier in China, offering ASTM A193 Gr. B7 AISI 4140 GB 42CrMo Steel Round Bar, High Strength Thread Stud Bolt ASTM A193 B7 in Petrochemical Industry, A193 B7 B7m B8 L7 Stud Bolts with Black and Zinc Finish, Petrochemical Industry Parts and so on.