Fault phenomenon

Inspection, adjustment, and judgment methods

Troubleshooting methods

Spindle heating

1) Excessive preload of the spindle bearing causes excessive friction during spindle rotation, leading to a sharp increase in spindle temperature.

It can be ruled out by readjusting the preload of the spindle bearing.

(2) Grinding or damage to the spindle bearings can also cause excessive friction during spindle rotation, causing a sharp increase in spindle temperature.

It can be ruled out by replacing the bearing with a new one.

(3) Dirty or impurities in the spindle lubricating oil can also cause excessive resistance during spindle rotation, leading to an increase in spindle temperature.

Remove the problem by cleaning the spindle box and changing the oil again.

(4) Exhaustion or excessive lubrication of the spindle bearing grease can also cause excessive resistance and friction during spindle rotation, leading to an increase in spindle temperature.

Eliminate by reapplying lubricating grease.

Spindle stops during heavy cutting

(1) The transmission belt connecting the spindle motor to the spindle is too loose, causing the spindle transmission torque to be too small. During strong cutting, the spindle torque is insufficient, causing an alarm and the CNC machine tool to automatically stop.

By readjusting the tension of the spindle drive belt, it can be ruled out.

(2) There is oil on the surface of the transmission belt connecting the spindle motor and the spindle, which causes the transmission belt to slip during spindle transmission. During strong cutting, the spindle torque is insufficient, and an alarm is generated, causing the CNC machine tool to automatically stop.

Remove by cleaning with gasoline or alcohol and wiping thoroughly.

(3) The transmission belt connected to the spindle motor and the spindle is ineffective due to prolonged use, resulting in the inability of the spindle motor to transmit torque. During strong cutting, the spindle torque is insufficient, and an alarm is generated, causing the CNC machine tool to automatically stop.

Eliminate the issue by replacing the main shaft drive belt with a new one.

(4) The clutch and coupling connections in the spindle transmission mechanism are too loose or worn, resulting in excessive torque transmission error of the spindle motor and strong spindle vibration during strong cutting. An alarm is generated, and the CNC machine tool automatically stops.

Eliminate by adjusting or replacing the clutch or coupling.

Excessive noise during spindle operation

(1) Poor dynamic balance of spindle components causes excessive vibration during spindle rotation, resulting in work noise.

Professional personnel from the machine tool manufacturer are required to re check and debug the dynamic balance of all spindle components.

(2) The wear of the main shaft transmission gear causes excessive gear meshing clearance, resulting in excessive impact vibration during the rotation of the main shaft and causing work noise.

Professional personnel from the machine tool manufacturer are required to inspect, repair, or replace the spindle transmission gear.

(3) The main shaft support bearing is roughened or damaged, resulting in excessive spindle rotation clearance, excessive impact and vibration during rotation, and causing work noise.

Professional personnel from the machine tool manufacturer are required to inspect, repair, or replace the bearings.

(4) The spindle drive belt is loose or worn, causing excessive friction during spindle rotation and causing work noise.

Eliminate it by adjusting or replacing the drive belt.

Tool cannot be clamped

(1) The displacement of the disc spring is too small, making it impossible for the spindle to grasp and clamp the tool to reach the correct position, and the tool cannot be clamped.

Exclude by adjusting the travel length of the disc spring.

(2) The spring collet is damaged, making it impossible for the spindle clamping device to clamp the tool.

Eliminate by replacing the spring collet with a new one.

(3) The failure of the disc spring prevents the spindle from grabbing and clamping devices from moving to the correct position, resulting in the inability of the tool to clamp.

Eliminate this by replacing the new disc spring.

(4) The pulling nail on the tool handle is too long, which collides with the spindle grasping and clamping device, making it unable to move to the correct position and the tool cannot be clamped.

Eliminate the issue by adjusting or replacing the pull pin and installing it correctly.

The tool cannot be loosened after clamping

(1) Insufficient pressure and stroke of the hydraulic cylinder for loosening the knife.

Eliminate by adjusting the hydraulic pressure and stroke switch position.

(2) The disc spring is pressed too tightly, preventing the spindle clamping device from fully moving to the correct position and preventing the tool from loosening.

By adjusting the nut on the disc spring, reduce the spring compression to eliminate it.