Causes Of Vibration Marks And Spiral Marks On Products Ground By CNC Grinding Machines
When grinding products on a CNC grinding machine, if vibration marks or spiral marks appear on the surface of the ground product, the causes may be varied. The following situations can be used as a reference for troubleshooting:
1. Is the Diamond Pen Loose?
If the diamond pen used to correct the grinding wheel becomes loose, the surface of the corrected grinding wheel will naturally become uneven, and surface quality issues in the ground products are inevitable.
2. Are the Speeds of the Grinding Wheel Spindle and Workpiece Spindle Stable?
Check whether the rotational speeds of the grinding wheel spindle and workpiece spindle are stable: When diagnosing spindle rotational speed, set the spindle being inspected to a specific speed and check the diagnostic parameters of the spindle controller to see if the speed is fluctuating and by how much. A tachometer can also be used to measure the speed. If the spindle rotational speed is unstable, the surface of the ground workpiece will exhibit ridges.
3. Are the Cooling Fans of the Grinding Wheel Spindle and Workpiece Spindle Motors Vibrating?
Vibration in the cooling fans of the main motors directly affects the surface quality of the ground products.
4. Inspection of the Grinding Head
Measure the radial runout and axial play of the grinding head. If the values exceed the specified limits, technical measures must be taken. If the radial runout of the grinding head exceeds the standard value, and the grinding head cannot be replaced, the viscosity of the grinding head spindle oil can be increased to mitigate the adverse effects of the grinding head on the grinding product.
5. Bedhead Box Claw and Self-aligning Plate
During the rotation of the workpiece being ground, if the bedhead box’s indexing claw has relative displacement with the workpiece being ground; or if the bedhead box’s self-aligning plate intermittently slides during the workpiece’s rotation, the surface quality of the ground workpiece will be significantly affected.