On the basis of the common CNC milling machine, some of them have the same structure. CNC milling machines are divided into two categories: without tool magazine and with tool magazine. The following is to introduce the characteristics of CNC milling machine.
1. Processing characteristics
For the processing part is the frame plane or unequal height of all levels of steps, then select the point line system of CNC milling machine. If the machining part is a curved surface contour, the two coordinate linkage system and the three coordinate linkage system should be selected according to the geometric shape of the curved surface. According to the requirements of parts processing, on the basis of general CNC milling machine, add CNC dividing head or CNC rotary table. At this time, the system of the machine tool is a four coordinate CNC system, which can process spiral groove, blade parts, etc.
2. Dimensions
The width of the worktable is less than 400mm, which is the most suitable for small and medium parts processing and complex surface contour milling. The larger size of the gantry type milling machine, worktable in 500-600mm above, used to solve the processing needs of large and complex parts.
3. Precision
China has formulated the accuracy standard of CNC milling machine, among which there are professional standards for CNC vertical milling machine and lifting table milling machine. According to the standard, the positioning accuracy of the linear motion coordinate is 0.04/300 mm, the repeated positioning accuracy is 0.025 mm, and the milling precision is 0.035 mm. In fact, the accuracy of the machine tool factory has a considerable reserve, about 20% less than the national standard tolerance. Therefore, from the perspective of precision selection, the general CNC milling machine can meet the processing needs of most parts. For parts with high precision requirements, precision CNC milling machine should be selected.
4. Batch
For large quantities of goods, special milling machine can be used. If it is a medium and small batch and it is often put into production periodically, then it is very suitable to use CNC milling machine, because a lot of fixtures and programs prepared in the first batch can be stored and reused. In the long run, it is inevitable that the milling machine with high degree of automation will replace the ordinary milling machine, reduce the labor of workers and improve productivity.
