Pre-Startup Equipment Inspection
Before each shift, conduct a thorough inspection of the quenching machine. Check that all control cabinet doors are closed and door switch interlocks are reliable and effective. Verify control panel indicator lights are intact and all grounding wires are reliably connected. Check that thermocouple leads are correctly connected to the instrument terminals.
For electric contact heating quenching, check that roller electrodes are intact and workpiece surfaces are free of defects and iron powder particles. Verify that the step-down transformer is functioning normally, with secondary voltage not exceeding 5 volts and secondary current not exceeding 750 amperes. If abnormal sparks occur during the quenching process, immediately stop the machine and identify the cause.
For electrolytic heating quenching, verify the insulation level of the electrolyte tank, the working condition of electrical equipment, and the working voltage and current. Check the chemical composition of the electrolyte before use. The electrolyte temperature must not exceed 60 degrees Celsius during operation, and temperature measurement must use dedicated instruments. The work area must be well ventilated and smoking, drinking, and eating are strictly prohibited.
Startup and Operation Procedures
When using machine tool equipment for surface quenching, first check that all machine components are in good condition, motor sounds are normal, and rotating parts are regularly lubricated. When reversing the machine, wait until the motor has completely stopped. Always wear protective goggles during operation. Before quenching, check that the nozzle is unobstructed and free of defects, and never point the nozzle at people. Adjust the cooling water first, then open the acetylene to ignite, then open the oxygen to adjust the flame.
During high-frequency operations, strictly follow process specifications to control roller electrode speed. Operate according to the prescribed startup sequence: first open a small amount of oxygen, then open acetylene to ignite, then adjust. When extinguishing, first close the acetylene valve, then close the oxygen valve. To prevent nozzle hole explosion, you can also first close some oxygen without fully closing, then close acetylene, and finally fully close the oxygen valve.
Cooling System Management
Maintain quenching cooling water readiness before starting work. Water cooling for the quenching machine is critical for equipment protection. Cooling water pressure should normally be maintained within specified limits. After completing work, equipment should continue receiving cooling water for 15 to 20 minutes to allow electron tubes and other heat-generating components to cool adequately before fully shutting down the water supply.
Emergency Handling
If abnormal conditions occur during equipment operation, first disconnect high voltage, then analyze and troubleshoot the fault. When inspecting equipment, first make an announcement, then open the machine door and use a discharge rod to discharge the anode, grid, capacitor, and other components before proceeding with maintenance. Operators should not perform maintenance alone.
If acetylene hose catches fire, bend the hose at the point above the fire. If oxygen hose catches fire, do not use the bending method - instead, close the upstream oxygen valve. When loading or unloading heavy items on the quenching machine, a designated person must supervise to prevent accidents. After work is completed, promptly close the oxygen and acetylene valves, then use oxygen to purge once more to confirm no acetylene remains before stopping work.
Workplace Safety
The work area floor must be kept clean and dry at all times. Electrical switches must not have conductive items nearby. Workpieces near the furnace must be cooled before handling to prevent burns. After completing work, organize oxygen and acetylene hoses and clean the work area. Equipment must be kept clean and well-maintained to ensure safe and reliable operation.
