How to maintain and maintain the CNC machining center

How to maintain and maintain the CNC machining center?
Daily machining accuracy maintenance of machining centers：

After starting up, it must be preheated for about 10 minutes before processing; if the machine is not used for a long time, the preheating time should be extended;
Check whether the oil circuit is smooth;
Before shutting down, place the workbench and saddle at the center of the machine (move the three-axis stroke to the middle position of each axis stroke);
The machine tool is kept dry and clean.

Daily maintenance

Clean and clean the dust and iron filings of the machine tool every day: including machine tool control panel, spindle taper hole, tool cart, tool head and taper handle, tool magazine arm and tool warehouse, turret; XY axis sheet metal shield, machine tool Inner flexible hose, tank chain device, chip flute, etc.;
Check the level of lubricating oil to ensure the lubrication of the machine tool;
Check whether the coolant in the coolant tank is sufficient, and if it is not enough, add it in time;
Check whether the air pressure is normal;
Check whether the air blowing of the cone hole in the spindle is normal, wipe the cone hole in the spindle with a clean cotton cloth, and spray light oil;
Clean the tool magazine arm and tool, especially the claw;
Check whether all signal lights and abnormal warning lights are normal;
Check whether there is leakage in the oil pressure unit pipe;
After the daily work of the machine tool is completed, carry out cleaning and cleaning work;
Keep the environment around the machine clean.

weekly maintenance

Clean the air filter of the heat exchanger, the filter of the cooling pump and lubricating oil pump;
Check whether the pull bolt of the tool is loose and whether the handle of the knife is clean;
Check whether the three-axis mechanical origin is offset;
Check whether the movement of the tool change arm of the tool magazine or the rotation of the knife disc of the tool magazine is smooth;
If there is an oil cooler, check the oil of the oil cooler, if it is lower than the scale line, please fill in the oil cooler oil in time;
Clean the impurities and water in the compressed gas, check the amount of oil in the oil mist separator, check whether the solenoid valves are working normally, and check the sealing of the pneumatic system, because the quality of the gas system directly affects the replacement Knife and lubrication system;
Prevent dust and dirt from entering the CNC device. In the machining workshop, there are generally oil mist, dust and even metal powder in the air. Once they fall on the circuit board or electronic devices in the CNC system, it is easy to cause the insulation resistance between components to drop, and even cause damage to components and circuit boards. .

monthly maintenance

Check the lubrication condition of the shaft track, and the track surface must be well lubricated;
Check and clean limit switches and touch blocks;
Check whether the oil in the knife cylinder oil cup is sufficient, and add it in time if it is insufficient;
Check whether the indication plate and warning nameplate on the machine are clear and exist.

half year maintenance

Disassemble the shaft chip protection cover, clean the shaft oil pipe joint, ball guide screw, three-axis limit switch, and check whether it is normal. Check whether the hard rail wipers of each axis are in good condition;
Check whether the servo motors of each axis and the head are running normally, and whether there is any abnormal sound;
Replace the oil of the hydraulic unit and the oil of the deceleration mechanism of the tool magazine;
Test the clearance of each axis, and adjust the compensation amount if necessary;
Clean the dust in the electrical box (make sure the machine is turned off);
Comprehensively check whether the contacts, joints, sockets and switches are normal;
Check whether all keys are sensitive and normal;
Check and adjust the mechanical level;
Clean the cutting water tank and replace the cutting fluid.

Annual professional maintenance or repair
Note: Professional maintenance or repairs should be performed by professional engineers.

The grounding protection system should have good continuity to ensure personal safety;
Carry out regular inspections on vital parts such as circuit breakers, contactors, single-phase or three-phase arc extinguishers. If the wiring is loose or the noise is too loud, find out the reason and eliminate hidden dangers;
Ensure that the cooling fan in the electric cabinet is running normally, otherwise it may cause damage to the vitality parts;
If the fuse is blown and the air switch trips frequently, the cause should be found out and eliminated in time;
Check the vertical accuracy of each axis and adjust the geometric accuracy of the machine tool. Restore or meet the requirements of the machine tool. Because geometric accuracy is the basis of the comprehensive performance of machine tools. For example, if the verticality of XZ and YZ is not good, it will affect the coaxiality and symmetry of the workpiece, and if the perpendicularity of the spindle to the table is not good, it will affect the parallelism of the workpiece and so on. Therefore, the recovery of geometric accuracy is the focus of our maintenance;
Check the wear and clearance between the motors of each axis and the screw rods, and check whether the supporting bearings at both ends of each axis are damaged. When the coupling or bearing is damaged, it will increase the noise of the machine tool operation, affect the transmission accuracy of the machine tool, damage the cooling seal ring of the screw rod, cause the leakage of cutting fluid, and seriously affect the life of the screw rod and spindle;
Check the protective cover of each axis and replace it if necessary. If the protective cover is not good, it will directly accelerate the wear of the guide rail. If there is a large deformation, it will not only increase the load on the machine tool, but also cause greater damage to the guide rail;
The straightening of the screw rod, because some users cause the deformation of the screw rod after the machine tool collides or the gap between the plug iron is not good, which directly affects the machining accuracy of the machine tool. We first loosen the screw rod to make it in a natural state, and then install the screw rod according to the maintenance regulations to ensure that the screw rod is free from tangential force as much as possible during the movement, so that the screw rod is also in a natural state during processing;
Check and adjust the belt transmission system of the main shaft of the machine tool, properly adjust the tightness of the V-belt, prevent the machine tool from slipping or losing rotation during processing, replace the V-belt of the main shaft if necessary, and check the pressure belt of the 1000r/min main shaft for high and low gear conversion The amount of oil in the wheel cylinder. Add it when necessary, lack of oil will cause failure during low gear conversion, seriously affect the surface roughness during milling, and reduce the cutting torque to the bottom;
Cleaning and adjustment of the tool magazine. Adjust the rotation of the tool magazine to make it parallel to the table, replace the circlip if necessary, adjust the angle of the spindle orientation bridge and the rotation coefficient of the tool magazine, and add lubricating grease to each moving part;
Prevent the system from overheating: You should check whether the cooling fans on the CNC cabinet are working normally. Check whether the air duct filter is clogged. If there is too much dust on the filter, if it is not cleaned in time, the temperature in the CNC cabinet will be too high;
Regular maintenance of the input/output device of the CNC system: Check whether the transmission signal line of the machine tool is damaged, whether the interface and connector screw nuts are loose and fall off, whether the network cable is inserted firmly, and the router is cleaned and maintained;
Regular inspection and replacement of DC motor brushes: Excessive wear of DC motor brushes will affect the performance of the motor and even cause damage to the motor. For this reason, regular inspection and replacement of motor brushes should be carried out. CNC lathes, CNC milling machines, machining centers, etc. should be inspected once a year;
Regularly check and replace the storage battery: the general numerical control system has a rechargeable battery maintenance circuit for the CMOS RAM storage device to ensure that the system can maintain the contents of the memory when the system is not powered on. In general, even if they haven’t failed, they should be replaced once a year to ensure the system works properly. The replacement of the battery should be carried out under the power supply state of the CNC system to prevent the information in the RAM from being lost during the replacement;
Clean the electrical components in the control cabinet, check and fasten the fastening state of the terminals; clean and clean the CNC system control module, circuit board, fan, air filter, heat sink, etc.; clean the internal components of the operation panel, circuit board, Fan, check the fastening state of the connector