1.grey iron, ductile iron, iron alloy 2.hardness: 140HB-260HB 3.competitive price 4.strict QC system, ... and pneumatic parts field: valve, fairlead, gear wheel and piston;2. Machine tool parts: sea saw, guiding rail, worktable and transmission ... ;3. Metallurgy machine parts: the transporting roller for the high-speed wire rolling mill; 4. Refrigerator compressor parts: piston ring and ...