The correct operation and maintenance of CNC equipment can prevent abnormal wear and sudden failure of machine tools. Careful maintenance of machine tools can maintain the long-term stability of machining accuracy and prolong the service life of machine tools. This work must be highly valued and executed from the management level of the factory!
Responsible person for maintenance
1. Operators shall be responsible for the use, maintenance and basic maintenance of equipment;
2. Equipment maintenance personnel shall be responsible for equipment maintenance and necessary maintenance;
3. Workshop management is responsible for the supervision of all operators and equipment maintenance in the whole workshop.
Basic requirements for using numerical control equipment
1. CNC equipment requirements to avoid moisture, dust and corrosive gas too much place;
2. avoid direct sunlight and other thermal radiation, precision CNC equipment should be away from the vibration of large equipment, such as punch, forging equipment, etc.;
3. The operating temperature of the equipment should be controlled between 15 degrees and 35 degrees. Precision machining temperature should be controlled at about 20 degrees, strictly control the temperature fluctuation;
4. In order to avoid the influence of large power supply fluctuation (more than plus or minus 10%) and possible instantaneous interference signals, CNC equipment generally uses dedicated line power supply (such as from the low voltage distribution room for a separate CNC machine tool), adding voltage regulator device, etc., can reduce the influence of power supply quality and electrical interference.
Maintaining daily machining accuracy
1. After starting the machine, it must be preheated for about 10 minutes before processing; Long-term use of the machine should be extended preheating time;
2. Check whether the oil circuit is smooth;
3. Put the table and saddle in the center of the machine before shutdown (move the three-axis stroke to the middle position of each axis stroke);
4. Keep the machine dry and clean.
Daily maintenance
1. Clean the dust and iron dust of the machine tool every day: including the machine tool control panel, spindle cone hole, tool car, tool head and taper shank, tool store tool arm and tool bin, turret; XY axis sheet metal shield, flexible hose in machine tool, tank chain device, chip groove, etc.;
2. Check the lubricating oil level height to ensure machine lubrication;
3, check whether the coolant box coolant is enough, not enough to add in time;
4. Check whether the air pressure is normal;
5. Check whether the air blowing in the cone hole of the spindle is normal, wipe the cone hole in the spindle with clean cotton cloth, and spray light oil;
6. Clean the knife arm and tool in the knife library, especially the knife claw;
7. Check all signal lights and abnormal warning lights.
8. Check whether there is leakage in the oil pressure unit pipe;
9. Clean the machine after daily work;
10. Keep the environment around the machine clean.
Weekly maintenance
1. clean the air filter of heat exchanger, cooling pump, lubricating oil pump filter;
2. Check whether the pull bolt of the tool is loose and whether the handle is clean;
3. Check whether the origin of the three-axis machinery is offset;
4. Check whether the tool arm change action or the tool head rotation of the tool library is smooth;
5. If there is an oil cooler, check the oil cooler oil. If it is lower than the scale line, please fill the oil cooler oil in time.
6, clean the impurities and water in the compressed gas, check the amount of oil in the oil mist separator, check whether the solenoid valve is working normally, check the sealing of the pneumatic system, because the quality of the air path system directly affects the tool change and lubrication system;
7. Prevent dust and dirt from entering the CNC device. There will generally be oil mist, dust and even metal powder in the air of the machine workshop. 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 lead to the damage of components and circuit boards.
Monthly maintenance
1. Test shaft track lubrication, track surface must ensure good lubrication;
2. Check and clean the limit switch and block;
3. Check whether the oil in the oil cup of the cutter cylinder is enough, and add it in time if it is insufficient;
4. Check whether the signs and warning nameplates on the machine are clear and exist.
Six months of maintenance
1. Disassemble the shaft anti-chip cover, clean the shaft tubing joint, ball guide screw and three-axis limit switch, and check whether it is normal. Check whether the effect of each shaft hard rail brush blade is good;
2. Check whether the shaft servomotor and head operate normally and whether there is abnormal sound;
3. Replace oil of oil pressure unit and reducer oil of tool store;
4. Test the clearance of each shaft, and adjust the compensation amount when necessary;
5. Clean the dust in the electric box (ensure that the machine is closed);
6, check all the contacts, joints, sockets, switches are normal;
7. Check whether all keys are sensitive and normal;
8. Check and adjust the mechanical level;
9. Clean the cutting water tank and replace the cutting fluid.
Annual professional maintenance or repair
Note: Professional maintenance or repair should be carried out by professional engineers.
1. The grounding protection system should have good continuity to ensure personal safety;
2, the circuit breaker, contactor, single-phase or three-phase arc extinguisher and other components to carry out regular inspection. If the wiring is loose, whether the noise is too large, find out the reason and eliminate hidden dangers;
3. Ensure the normal operation of the cooling fan in the electric cabinet, otherwise it may lead to the damage of the vitality parts;
4. The fuse is blown and the air switch trips frequently. The reason should be found out in time and excluded.
5, check the vertical accuracy of each axis, adjust the geometric accuracy of the machine tool. Restore or meet the requirements of machine tools. Because geometric accuracy is the basis of the comprehensive performance of machine tools. For example: XZ, YZ perpendicularity is not good will affect the coaxiality and symmetry of the workpiece, the spindle of the mesa perpendicularity is not good will affect the parallelism of the workpiece and so on. Therefore, the restoration of geometric accuracy is the focus of our maintenance;
6. Check the wear and clearance of each shaft motor and lead rod, and check whether the supporting bearings at both ends of each shaft are damaged. When the coupling or bearing is damaged, it will increase the noise of the machine operation, affect the transmission accuracy of the machine tool, damage the lead screw cooling seal ring, lead to the leakage of cutting fluid, seriously affect the life of the lead screw and spindle;
7. Check the protective cover of each shaft and replace it if necessary. The protective cover is not good to directly accelerate the wear of the guide rail, if there is a large deformation, not only will increase the load of the machine tool, but also cause great damage to the guide rail;
8, the straightening of lead screw, because some users in the machine tool collision or plug iron gap is not good cause lead screw deformation, directly affect the processing accuracy of the machine tool. We first relax the lead screw, so that it is in a natural state, and then follow the maintenance procedures to install the lead screw, to ensure that the lead screw is not tangential force in the movement as far as possible, so that the lead screw is in a natural state in the processing;
9. Check and adjust the belt drive system of the spindle of the machine tool, properly adjust the tightness of the V belt to prevent the machine tool from slipping or losing spin in the processing. If necessary, replace the V belt of the spindle, and check the amount of oil in the cylinder of the high-pressure belt wheel of the 1000R /min spindle. When necessary, the lack of oil will cause the failure of low grade conversion, seriously affect the surface roughness of milling processing, so that the cutting torque drop to the bottom;
10. Cleaning and adjustment of knife library. Adjust the rotation of the tool library to make it parallel to the table, replace the clamping spring when necessary, adjust the Angle of the spindle directional bridge and the rotation coefficient of the tool library, add lubricating grease in each moving part;
11. Prevent overheating of the system: it is necessary to check whether the cooling fans on the CNC cabinet work normally. Check whether the air duct filter is blocked. If the dust on the filter network accumulates too much and is not cleaned up in time, the temperature in the NC cabinet will be too high.
12. 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 properly, and whether the router is cleaned and maintained;
13. DC motor brush regular inspection and replacement: DC motor brush excessive wear, affect the performance of the motor, and even cause motor damage. Therefore, the motor brush should be regularly checked and replaced, CNC lathes, CNC milling machines, machining centers, etc., should be checked once a year;
14. regular inspection and replacement of storage batteries: general CNC system on the CMOS RAM memory device is provided with a rechargeable battery maintenance circuit to ensure that the system is not powered on during the retention of its memory content. In general, even if it has not failed, it should be replaced once a year to ensure that the system works properly. Battery replacement should be carried out under the power supply state of the CNC system to prevent the loss of information in the RAM during replacement;
15. Clean the electrical components in the control cabinet, check and tighten the fastening state of the wiring terminals; Cleaning, cleaning CNC system control module, circuit board, fan, air filter, cooling device, etc.; Clean components, circuit boards, fans, and connectors on the operation panel.
Post time: Aug-27-2022