The number of maintenance points for a CNC machine tool depends on factors such as its type, size, and complexity. The specific number of maintenance points will vary. Here are some possible types of maintenance points you can consider when maintaining your machine tools:

1. Lubrication part: The lubrication system of CNC machine tools requires regular maintenance. This includes oil changes, filling and checking the operation of the lubrication system.
2. Transmission system: The transmission system of CNC machine tools usually involves various transmission devices, such as belts, gears, screws, etc. These transmission components need to be inspected regularly to ensure they are working properly, such as checking the wear, tightness and lubrication of the transmission.
3. Spindle and bearings: The spindle and bearings of CNC machine tools are key components and require regular maintenance and upkeep. This includes cleaning the spindle and bearings, checking lubrication, calibrating axial clearance, etc.
4. Electrical system: The electrical system of CNC machine tools needs maintenance and inspection, including cable connection, tightening of electrical components and power-on testing, etc.
5. Cooling system: CNC machine tools are usually equipped with a cooling system to control the temperature and cool down the heat generated during the cutting process. Cooling systems require regular checks of coolant levels and quality, as well as cleaning of coolers and cooling ducts.
6. Machine bed and fixtures: The bed and fixtures of CNC machine tools need to be kept clean and their integrity and stability checked regularly.
7. CNC system: The CNC system of CNC machine tools requires regular software upgrades and calibrations to ensure its normal operation and accurate control of the machining process.

To sum up, the number of maintenance points for CNC machine tools may include lubrication parts, transmission systems, spindles and bearings, electrical systems, cooling systems, machine tool beds and fixtures, and CNC systems, etc. The specific number of maintenance points may vary depending on factors such as machine tool model, manufacturer specifications and configuration. It is recommended to refer to the relevant documentation and maintenance manual of the machine tool to understand the maintenance points and maintenance intervals of the specific machine tool. At the same time, according to the working conditions of the machine tool, the maintenance plan is reasonably arranged and regular maintenance and upkeep are carried out to ensure the stability and good working condition of the machine tool.