There are many factors that affect the accuracy of CNC vertical lathe, the following are some of the main factors:

1. Mechanical structure of the machine tool: The mechanical structure of the machine tool of the CNC vertical lathe has a direct impact on the machining accuracy. The rigidity, stability, guide rail accuracy, and lead screw transmission accuracy of the machine tool will all have an impact on the machining accuracy.
2. Numerical control system: The numerical control system is the core of controlling the movement of the CNC vertical lathe, and its stability and precision are crucial to the processing results. The precision, sampling rate, interpolation algorithm and feedback control method of the CNC system will all affect the precision of the final machining.
3. Servo system: The servo system controls the movement of each axis of the CNC vertical lathe, which plays a key role in the processing accuracy. The accuracy of the servo system, the accuracy of the feedback device, and the control method will all affect the accuracy of the machining.
4. Tool system: The rigidity, geometric accuracy and wear state of the tool will all have an impact on the machining accuracy. The influence of cutting force on the tool will also be transmitted to the workpiece, affecting the machining accuracy.
5. Workpiece clamping and clamping methods: The stability and accuracy of workpiece clamping and clamping methods have an important impact on machining accuracy. Factors such as the rigidity, symmetry and stability of the fixture will affect the accuracy of the machining results.
6. Processing parameters: Processing parameters include cutting speed, feed speed, cutting depth, etc. The selection and adjustment of these parameters will directly affect the processing accuracy. Proper selection and optimization of processing parameters can improve the processing accuracy.
7. Environmental factors: Environmental factors such as temperature, humidity, vibration, etc. will also affect the accuracy of CNC vertical lathe. Temperature changes will cause thermal expansion or contraction of the machine tool, and humidity changes may cause corrosion of machine tool parts, etc., which will affect the machining accuracy.
8. The technical level of the operator: The technical level and experience of the operator have an important impact on the accuracy of the operation and adjustment of the CNC vertical lathe. Qualified operators master the correct operation methods and adjustment skills, which can ensure the precision of processing.

To sum up, the precision of CNC vertical lathe is affected by multiple factors such as machine tool mechanical structure, CNC system, servo system, tool system, workpiece clamping, processing parameters, environmental factors and operator technical level. To obtain high-precision machining results, these factors need to be considered and optimized comprehensively.