The requirements of the CNC vertical lathe on the spindle are very critical, because the spindle carries the force and speed of the cutting tool and the cutting operation. The following are some common requirements for the spindle of CNC vertical lathe:

1. High rigidity: The spindle needs to have sufficient rigidity to withstand cutting forces and vibrations and maintain a stable cutting process. The high-rigidity spindle can reduce vibration and deformation, improve machining accuracy and surface quality.
2. High speed: CNC vertical lathes usually require high-speed cutting operations, so the spindle needs to have high speed capabilities to meet processing requirements. The high-speed spindle can achieve faster cutting speed and improve production efficiency.
3. Good cooling and lubrication system: The spindle needs to be equipped with a good cooling and lubrication system to ensure that the spindle bearing and tool contact area can be effectively cooled and provide sufficient lubrication when running at high speed. This helps extend spindle life and reduces friction and wear.
4. High precision: The spindle needs to have high-precision rotation characteristics to ensure the precision requirements of the processing size and geometric shape. Precise spindle design and machining can reduce radial and axial errors and ensure machining accuracy and consistency.
5. Reliability and durability: CNC vertical lathes are usually used for long-term and high-intensity processing. The spindle needs to be reliable and durable, able to withstand long-term working loads, and have a long service life.

It should be noted that the specific CNC vertical lathe spindle requirements will be affected by the type of machine tool, workpiece material, processing requirements and manufacturer. Therefore, when choosing a CNC vertical lathe, it is recommended to consult a professional machine tool manufacturer or technical expert to select the appropriate spindle configuration according to the specific situation.