When dividing the working procedure of CNC machining, we must grasp flexibly the structure and technology of parts, the function of the CNC machining center, the number of NC machining contents, the installation times, and the production organization of the unit. In addition, it is suggested that the principle of process centralization or process decentralization should be adopted according to the actual situation, but it must be reasonable. Generally, the division of working procedures can be carried out according to the following methods:
1. The method of tool centralized sequence.
This method divides the working procedure according to the tool used and processes all the parts that can be completed on the part with the same tool. To reduce the tool change time, idle travel time, and unnecessary positioning error, parts can be processed according to the method of tool centralized process, that is, in one clamping process, the parts can be processed with one tool as far as possible, and then another tool is used to process other parts. In this way, the number of tool changes can be reduced, the idle travel time can be compressed, and the unnecessary positioning error can be reduced.
2. According to the method of processing parts.
Each part has a different structure and shape, and the technical requirements of each surface are also different. Therefore, the positioning methods are different during processing, so the working procedure can be divided according to the different positioning methods.
For parts with a lot of processing contents, the processing part can be divided into several parts according to its structural characteristics, such as internal shape, shape, surface or plane, etc. Generally, the plane and positioning surface are processed first, and then the hole; the simple geometric shape is processed first, and then the complex geometric shape; the parts with low precision are processed first, and then the parts with high precision requirements are processed.
3. The method of rough and fine machining is used.
When the working procedure is divided according to the machining accuracy, rigidity, and deformation of the parts, the working procedure can be divided according to the principle of separating the rough machining and the finishing machining, that is, the rough machining is first followed by the finishing machining, and then different machine tools or different cutting tools can be used for processing; For parts prone to machining deformation, due to the deformation that may occur after rough machining, it is necessary to carry out shape correction. Therefore, generally speaking, the process of rough and finished machining should be separated.
FAQ:
Proper division of CNC machining procedures ensures higher efficiency, better precision, and reduced errors. It allows manufacturers to make full use of the machine’s capabilities while minimizing setup time and tool changes.
You should consider the structure and technology of the parts, the function of the CNC machine, the number of machining operations, the number of setups, and the production organization of the unit.
This method groups machining steps by the tool used. All features that can be machined with the same tool are completed in one setup before switching to another tool, which minimizes tool changes and idle travel time.
It helps reduce tool change time, non-cutting travel time, and positioning errors. It also improves production efficiency by completing more operations in a single setup.
Procedures can be divided based on different positioning methods required by each surface of the part. For example, internal shapes, external shapes, planes, and holes can be processed in separate stages according to structural features.
Typically, machinists process planes and positioning surfaces first, then holes. They machine simple shapes before complex ones, and low-precision areas before high-precision ones.
Separating rough and fine machining ensures better accuracy and part stability. Rough machining removes most of the material, while finishing ensures the final precision and surface quality.
Rough machining can cause part deformation. Using separate setups or tools for finishing allows for shape correction and stress relief, leading to higher precision and stability.
By grouping operations logically—such as using the same tool or positioning method—manufacturers can reduce setup errors, alignment issues, and inconsistent machining accuracy.
The goal is to maximize machining efficiency, reduce production costs, and ensure consistent accuracy. Properly dividing procedures allows smooth workflow and better-quality parts.
