Summary of fault problems and solutions of main shaft of dividing machine

The high-speed motorized spindle is one of the core components of the board splitting machine. In the board splitting machine, the high-speed motorized spindle used under high load for a long time usually has various faults. What are the common faults of the main shaft of the board splitting machine? How to solve these faults?

1、 The noise and vibration of the main shaft of the dividing machine are large

Cause analysis: the bearing or other parts of the main shaft are damaged due to improper assembly, the accuracy of the bearing is low or poor retention, the coaxiality of the stator and rotor is poor, the air gap between the stator and rotor is uneven, the manufacturing accuracy of the main shaft parts is low or deformed after long-term use, which destroys the balance accuracy, the preload is too small, or the spring is not installed in place or even broken, Broken or poor contact of rotor cage bar, poor rigidity of grinding wheel connecting rod and low precision.

Treatment method: select better bearings, correct the coaxiality of stator and rotor, check the accuracy of main parts such as shell, rotating shaft, rotor and large cover, increase the preload, reassemble the motorized spindle, and select the grinding wheel extension rod with good rigidity and high precision to ensure the normal and stable operation of motorized spindle.

2、 The main shaft of the dividing machine is stuck and cannot rotate

Cause analysis: the bearing in the main shaft is worn and blocked by sundries, resulting in bearing jamming; The gap between the front dust ring and the rear dust ring is blocked by foreign matters.

Treatment method: send the spindle back for maintenance.

3、 The collet cannot be locked, resulting in knife falling and knife breaking

Cause analysis: the conical surface at the front end of the rotor is damaged, and the chuck surface is deformed and damaged.

Treatment method: please send the spindle back for cone grinding. The damaged collet cannot be used anymore.

4、 The spindle temperature is too high during use

Cause analysis: the spindle has been used for a long time and no cooling measures have been taken; The bearing is damaged.

Treatment method: take cooling measures for the spindle. It is recommended to use water cooler and heat dissipation fixture to cool the spindle; Send the spindle back to our company for disassembly and maintenance.

5、 The main shaft of the splitter is locked, but the frequency converter shows power output

Cause analysis: the phase voltage may be unbalanced.

Treatment method: check whether the connection between the main shaft and the drive line, the drive line and the frequency converter is good.

6、 The main shaft of the distributor stops rotating and cannot be started

Cause analysis: the main shaft stator coil may be burnt out or the coil insulation paint may melt. Check the fault information of the frequency converter and whether the frequency converter is braked.

Treatment method: firstly, use a multimeter to measure whether the resistance between the three UVW pins of the socket at the rear end of the spindle is balanced; Then check the service environment and whether the sealing gas is filtered and regulated by the filtering and pressure regulating device; Check the frequency converter parameter setting and adjust the frequency converter parameters. If the resistance value is unbalanced, it can be determined that the stator coil is burned; Send the spindle back for maintenance.

7、 It is difficult to start the main shaft of the dividing machine

Cause analysis: the power plug is not plugged in properly, the contact is poor or not connected, the power supply power is insufficient or does not match with the motorized spindle, the starting protection of the frequency converter is not adjusted to the optimal value, the power phase is missing or the contactor is in poor contact, which will lead to the difficulty of starting the motorized spindle. Excessive preload of the bearing in the motorized spindle and mutual friction between parts will also lead to its starting difficulties. However, in most cases, the reasons for its starting difficulties are: wrong connection of motor stator outgoing line in the motorized spindle, too small air gap between stator and rotor and damage of stator winding.

Treatment method: first check the power supply voltage, current and power, check whether the power supply condition is normal, readjust the frequency converter according to the electrical parameters of the motorized spindle, and then check the ground insulation of the stator winding and the balance state of the three-phase winding. Once a fault is found, repair it immediately. If the air gap between stator and rotor is too small, grind the outer diameter of rotor to maintain the design value of stator and rotor gap. If there is friction between parts, grind the outer diameter of parts to ensure sufficient clearance between them. Modifying the given value of preload can also improve the starting condition of motorized spindle. Therefore, when it is difficult to start the motorized spindle, specific solutions should be found for the equipment.

8、 Poor machining accuracy

Cause analysis: the bearing precision is low, the spindle precision is poor, the spindle precision is lost due to man-made damage or long-time work, the fit between the front bearing seat and the bearing is too loose, the preload is too small or the parts are stuck, the front and rear nuts are loose, the shaft moves, and the quality of the grinding wheel connecting rod is poor.

Treatment method: select better bearings, reassemble them, re grind the seat hole and main shaft to the required accuracy after hard chromium plating, increase the pre tightening force, lock the front and rear nuts, lock them with anti loosening set screws, and select the grinding wheel extension rod with good rigidity and high precision.

9、 Deceleration or unstable speed

Cause analysis: the power supply voltage is too low, does not match the electrical parameters, the power is small, and the rotor cage bar is broken or in poor contact.

Treatment method: firstly, check whether the power output, frequency, voltage and power match the motorized spindle. If the power of the motorized spindle is too small, select the motorized spindle with high power that meets the requirements of working conditions, check the cage quality, and select the motorized spindle with large capacity.

10、 Continuous burning loss of bearing

Cause analysis: poor lubrication, high speed, too small or too large preload and too large load.

Treatment method: replace the grease or check the oil mist quality, check the oil supply of the oil passage, measure the speed, adjust the frequency converter to ensure the normal operation of the motorized spindle, detect and adjust the preload to achieve the best value.