Proper operation and maintenance of CNC equipment can prevent abnormal wear of machine tools and avoid sudden failures. Careful maintenance of machine tools helps maintain long-term stability of their machining accuracy and extends their service life. This work must be given high priority and strictly implemented at the factory management level!

▌ Responsible Persons for Maintenance and Care

1. Operators are responsible for the use, maintenance, and basic care of the equipment;

2. Equipment repair personnel are responsible for equipment repair and necessary maintenance;

3. Workshop managers are responsible for supervising all operators and equipment maintenance across the entire workshop.

▌ Basic Requirements for Using CNC Equipment

1. CNC equipment should be placed in environments that avoid excessive moisture, dust, and corrosive gases;

2. Direct sunlight and other heat radiation should be avoided. Precision CNC equipment should be kept away from large-vibration equipment such as presses and forging machines;

3. The operating temperature of the equipment should be controlled between 15°C and 35°C. For precision machining, the temperature should be maintained around 20°C, with strict control over temperature fluctuations;

4. To mitigate the impact of large power supply fluctuations (greater than ±10%) and potential instantaneous interference signals, CNC equipment generally uses dedicated power lines (e.g., a separate line from the low-voltage distribution room for CNC machine tools) and additional voltage stabilizers, which can reduce the impact of power quality and electrical interference.

Daily Machining Precision Maintenance

1. After turning on the machine, it must be preheated for about 10 minutes before machining can commence; machines not used for a long time should have their preheating time extended.

2. Check if the oil circuit is unobstructed.

3. Before shutting down, position the worktable and saddle at the central location of the machine (move the three-axis travel to the middle position of each axis).

4. Keep the machine tool dry and clean.

Daily Maintenance and Care

1. Daily cleaning of machine tool dust and chips: This includes the machine tool control panel, spindle taper hole, tool carriage, tool head and taper handle, tool magazine arm and tool storage, turret; XY-axis sheet metal guards, flexible hoses inside the machine tool, tank chain devices, chip grooves, etc.

2. Check the oil level to ensure proper lubrication of the machine tool.

3. Check if the coolant in the coolant tank is sufficient; add it promptly if not.

4. Check if the air pressure is normal.

5. Check if the internal taper hole air blow of the spindle is functioning normally. Wipe the internal taper hole of the spindle with a clean cloth and apply light oil.

6. Clean the tool magazine arm and tools, especially the tool jaws.

7. Check if all signal lights and alarm warning lights are working properly.

8. Check for any leakage in the oil pressure unit hoses.

9. Perform cleaning and sweeping after daily operation of the machine tool.

10. Maintain a clean environment around the machine.

Weekly Maintenance

1. Clean the air filter of the heat exchanger, as well as the filters of the cooling pump and lubricating oil pump.

2. Check if the tool clamping bolts are loose and if the tool handles are clean.

3. Check if the three-axis mechanical origin has shifted.

4. Check if the tool changer arm movement or the tool magazine spindle rotation is smooth.

5. If there is an oil cooler, check the oil level in the oil cooler; add oil cooler oil promptly if it is below the (scale line).

6. Clean impurities and moisture from the compressed air, check the oil level in the oil mist separator, inspect the operation of each solenoid valve, and check the seal integrity of the pneumatic system, as the condition of the pneumatic system directly affects the tool changing and lubrication systems.

7. Prevent dust and contaminants from entering the interior of the CNC unit. In machine shop air, there are generally oil mist, dust, and even metal powder. Once these settle on circuit boards or electronic components inside the CNC system, they can easily cause a decrease in insulation resistance between components, and may even lead to damage to components and circuit boards.

Monthly Maintenance

1. Check the lubrication condition of the axis track, ensuring the track surface is well lubricated;

2. Inspect and clean the limit switches and their corresponding blocks;

3. Check if the oil cup of the tool-removing cylinder has sufficient oil, and add it promptly if not;

4. Verify that the signs and warning plates on the machine are clear and present.

Half-Year Maintenance

1. Remove the axis dust cover, clean the axis oil pipe joints, ball screw, three-axis limit switches, and check if they are functioning normally. Inspect the effectiveness of the hard rail scrapers on each axis;

2. Check if the servo motors and heads of each axis are operating normally and listen for any abnormal sounds;

3. Replace the oil in the hydraulic unit and the oil in the tool magazine speed reduction mechanism;

4. Test the gaps of each axis and adjust the compensation amount if necessary;

5. Clean the dust inside the electrical box (ensure the machine tool is powered off);

6. Conduct a comprehensive inspection of all contacts, connectors, sockets, and switches to ensure they are functioning normally;

7. Check if all buttons are responsive and working properly;

8. Check and adjust the mechanical level;

9. Clean the cutting fluid tank and replace the cutting fluid.

Annual Professional Maintenance and Repair

Note: Professional maintenance and repair should be carried out by professional engineers.

1. The grounding protection system should have intact continuity to ensure personal safety;

2. Regularly inspect components such as circuit breakers, contactors, single-phase or three-phase arc extinguishers. Check for loose wiring, excessive noise, identify causes, and eliminate potential hazards;

3. Ensure the cooling fans inside the electrical cabinet operate normally; otherwise, they may cause damage to components;

4. If fuses blow or air circuit breakers trip frequently, promptly identify and eliminate the causes;

5. Check the vertical accuracy of each axis and adjust the machine tool's geometric accuracy to restore or meet the machine tool's requirements. Geometric accuracy is the foundation of the machine tool's comprehensive performance. For example, poor perpendicularity of XZ and YZ axes will affect the coaxiality and symmetry of machined workpieces, and poor perpendicularity of the spindle to the table will affect the parallelism of machined workpieces, etc. Therefore, restoring geometric accuracy is a key focus of our maintenance;

6. Check the wear and clearance of each axis motor and lead screw, and check if the supporting bearings at both ends of each axis are damaged. Damaged couplings or bearings will increase machine tool operating noise, affect transmission accuracy, damage lead screw cooling seals, cause cutting fluid leakage, and seriously affect the service life of lead screws and spindles;

7. Check the protective covers of each axis and replace them if necessary. Poor protective covers directly accelerate guide rail wear. Significant deformation not only increases machine tool load but also causes severe damage to the guide rails;

8. Lead screw straightening: Some users' collisions or improper shimming gaps can cause lead screw deformation after machine tool collisions, directly affecting machining accuracy. We first relax the lead screw to its natural state, then install it in accordance with maintenance procedures to ensure the lead screw experiences minimal tangential force during operation, keeping it in a natural state during machining;

9. Inspect and adjust the belt drive system of the machine tool spindle. Properly adjust the tightness of the V-belt to prevent slippage or loss of rotation during machining. Replace the spindle V-belt if necessary, and check the oil level in the pulley cylinder for 1000r/min spindle high/low gear conversion. Add oil if necessary; insufficient oil can cause faults during low gear conversion, severely affecting surface roughness during milling and reducing cutting torque;

10. Cleaning and adjustment of the tool magazine. Adjust the tool magazine rotation to be parallel to the table. Replace circlips if necessary. Adjust the spindle orientation bridge angle and tool magazine rotation coefficient. Add lubricating grease to all moving parts;

11. Prevent system overheating: Check if the cooling fans on the CNC cabinet are working normally. Check for blockages in the air duct filters. Excessive dust accumulation on filters that is not cleaned promptly can cause excessively high temperatures inside the CNC cabinet;

12. Regular maintenance of CNC system input/output devices: Check for damage to machine tool signal transmission lines, loose or fallen interface and connector screws, secure network cable connections, and clean and maintain routers;

13. Regular inspection and replacement of DC motor brushes: Excessive wear of DC motor brushes affects motor performance and may even cause motor damage. Therefore, regular inspection and replacement of motor brushes are necessary. CNC lathes, CNC milling machines, and machining centers should be inspected annually;

14. Regular inspection and replacement of storage batteries: Most CNC systems have rechargeable battery maintenance circuits for CMOS RAM storage devices to retain memory content during power outages. Even if not yet failed, batteries should be replaced annually to ensure normal system operation. Battery replacement should be performed with the CNC system powered on to prevent data loss in RAM;

15. Clean electrical components inside the control cabinet, check and tighten terminal connections. Clean the CNC system control module, circuit boards, fans, air filters, and cooling devices. Clean internal components, circuit boards, and fans of the operation panel, and check the tightness of connectors.