... voltage controlled Zhengzhou Gou's New Quenching machine tool For Valve, Cylinder Main configuration:1, CNC system control;2, Stepper motor ... gear motor drive screw, screw the top down;7, Solenoid valve control water;8, With a heating device control plug.Gou ... hardened layer of regulation. So that the hardened layer of fine martensite, hardness, strength and toughness are high. 4) after heat ...