The cause of grooving vibration in vertical lathes during processing may involve multiple factors. Here are some common causes that may cause vibration in vertical lathes:

1. Improper tool selection: Using inappropriate tools may cause vibration. Tool selection should consider factors such as workpiece material, processing depth, and cutting speed. If the cutting tools do not match, it can cause vibration and unstable cutting.

2. Improper setting of cutting parameters: The setting of cutting parameters such as cutting speed, feed speed and cutting depth directly affects the stability of processing. Setting cutting parameters that are too high or too low can cause vibration.

3. The workpiece is not clamped firmly: If the workpiece is not clamped firmly or the clamping method is incorrect, the workpiece may vibrate during cutting. Ensuring that the workpiece is clamped securely is an important step in preventing vibration.

4. Machine tool rigidity problem: Insufficient machine tool rigidity may cause vibration. If the machine tool structure is not stable enough, vibration problems may occur during processing. Check whether the rigidity and structure of the machine tool are suitable.

5. Resonance during cutting: In some cases, resonance may occur during the cutting process, that is, the cutting force matches the natural frequency of the machine tool, causing vibration. This may need to be resolved by adjusting cutting parameters or changing the tool.

6. Tool wear: If the tool wear is severe, it may cause imbalance and vibration. Timely replacement of severely worn tools is an effective way to prevent vibration.

7. Insufficient or inappropriate cutting fluid: Cutting fluid not only reduces friction and cools the tool and workpiece, but also helps reduce vibration. Make sure there is an adequate supply of cutting fluid and select the appropriate cutting fluid.

8. Tool clamping problem: If the tool clamping is not firm or the clamping method is incorrect, it may cause the tool to vibrate during processing. Check that the tool holding system is functioning properly.

Solving the vibration problem of vertical lathe grooving usually requires comprehensive analysis of the above factors, adjusting cutting parameters, replacing tools, improving workpiece clamping, and checking the rigidity of the machine tool. When solving problems, it is best to conduct systematic inspections and adjustments to ensure that various factors work in harmony, thereby improving the stability and efficiency of processing.