There are many types of CNC machine tools, and each type of CNC machine tool has different characteristics due to its different functions, structures and systems. The content and rules of maintenance also have their own characteristics. The necessary maintenance system should be formulated and established according to the type, model and actual use of the machine tool, and with reference to the requirements of the machine tool instruction manual. Below are some common general maintenance points.

Maintenance of CNC machine tool shutdown

• Machine tool cleaning: Clean the workpieces and iron filings inside the machine tool, clean the iron filings in the external chip conveyor, wipe the external sheet metal, and clean the air conditioner and oil cooler filters of the electric control box.

• Anti-rust treatment: Clean and wipe the workbench and apply anti-rust oil; run the machine tool at a slow speed for one hour to lubricate the linear rails; if the cutting fluid needs to be replaced, prioritize anti-rust treatment and add cutting fluid when the machine tool starts to work. .

• Make sure to cut off the total power, gas, and fluid supply in the workshop: move the Y-axis of the CNC machine tool to the middle, return the Z-axis to zero, and turn off the main power switch of the machine tool, the transformer inlet switch, and the air source.

• Waterproof and moisture-proof: close the electrical box for protection.

• Anti-rodent treatment of machine tools: Machine tools should also be anti-rodent to prevent rats from chewing off the wires.

Start-up and debugging of CNC machine tools

• Inspection before starting: Check the peripheral environment of the machine tool, whether there are abnormal phenomena such as water intrusion in the electrical box, and whether the oil has deteriorated.

• Gradually start up: The power supply voltage of the machine tool must be checked before starting up. The main power switch must be turned on for about 10 minutes before the voltage is stable before the machine tool's power switch can be turned on. Then other power switches in the electrical box can be turned on to check whether the voltage is missing a phase or not. If it is too low, turn on the power of the machine tool if there are no abnormalities, and observe whether there are any abnormalities and whether there is air leakage. If there is no alarm when the machine is turned on, do not perform any action and leave the electrical components powered on for 30 minutes.

• Move at slow speed: Check whether there is any interference, move the machine tool all the way with the handwheel, and pay attention to whether there are any abnormalities, and then perform the origin return step.

• Machine tool running-in: Automatically run the machine tool at slow speed for a long time and rotate the spindle at low speed.

Common faults of CNC machine tools

• Fan failure: The fan in the machine tool can dissipate and cool down the core equipment, effectively preventing equipment from overheating and damage. At the end of a long holiday, machine tool fans often "go on strike" due to oil pollution. When the machine tool stops, the fan inside the machine tool will also stop. At this time, the oil in the machine tool will flow into the bearing of the fan, causing a short circuit failure in the fan circuit, and the fan will alarm or fail to start when the machine is turned on again. The longer the downtime, the greater the risk.

• Seal failure: Seals are indispensable in machine tool hydraulic and pneumatic devices to ensure the airtightness of the device and maintain its normal pressure supply. Seals are generally rubber products and are prone to aging. Especially during long holidays, when the machine tool is not running for a long time and the hydraulic pressure does not flow, it is more likely to cause the seals to harden, leading to oil leakage from the machine tool and insufficient pressure provided by the hydraulic device.

• Oil line blockage: The reason for oil line blockage is that the machine tool has been shut down for a long time and dirt in the oil line continues to accumulate. Blockage of the oil line will cause the machine tool's lubrication system to malfunction, and lubrication system failure will lead to many other serious problems. According to statistics, more than 40% of common machine tool faults are related to lubrication faults.

• Machine tool travel switch malfunction: The machine tool travel switch is an important device that limits the mechanical travel range of the machine tool coordinate axis. When the moving parts of the machine press the transmission components of the travel switch, its internal contacts act to connect, change or break the control circuit. Meet the control requirements for the circuit. There is generally a spring inside the limit switch. If the machine is not turned on for a long time, the spring will be deformed due to long-term stress and cannot be restored to its original shape. The spring will lose its function and the entire limit switch will be stuck and invalid.

• Circuit board failures such as drives, power supplies, and motherboards: In CNC machine tools, the role of circuit boards goes without saying. The circuit board has a large number of capacitors. If it is not powered for a long time, these capacitors will age, reducing the capacity and causing damage to the machine tool circuit. In addition, the main reason for circuit board failure is that long-term use will keep the circuit board at a low temperature for a long time, produce condensation water, and cause a short circuit when starting up.

• Machine tool battery failure: Generally, CNC systems are equipped with batteries. It should be noted that the battery mentioned here is not the power supply of the entire equipment, but a device that supplies power to certain parts. For example, the system battery is used to save system parameters; the battery for the absolute position encoder is used to remember the zero position. Even when the phone is not turned on, the power in these batteries slowly drains. If the machine is not turned on for a long time, the battery may be discharged easily, resulting in loss of machine tool data.

• For machine tools that have been used for a long time, try not to shut down the machine during the long holiday. You can take pictures of the emergency stop.

• Check the system fan regularly. If it is contaminated with excessive oil, it should be replaced or cleaned.

• Regularly check the hydraulic oil pressure, liquid level and hydraulic impurities in the hydraulic system to ensure smooth oil passage.

• Clean or lubricate spring devices such as switches, knife arm springs, and hydraulic valve springs regularly.

• Clean the drive equipment regularly according to the degree of oil contamination.

• Regularly replace the system battery of the machine tool and the desiccant in the machine tool electrical cabinet. This step should not be forgotten, especially before shutting down for a long vacation.

• After the long vacation, before restarting the machine, it is necessary to manually preheat each circuit board of the machine tool. You can use a hair dryer to heat each circuit board for a few minutes to keep it slightly warm.