The structural shapes of mechanical parts are diverse, but they are all composed of basic surfaces such as plane, outer circle, cylindrical surface, inner cylindrical surface or curved surface, and forming surface. There are multiple processing methods for each surface. On the CNC lathe, the turning, drilling, boring, reaming and tapping of the surface of the inner and outer slewing body can be completed. The specific selection should be based on the processing accuracy of the parts. For factors such as surface roughness, material, structure shape, size and production type, select the corresponding processing method and processing plan.
When the processing quality requirements of the parts are high, it is often impossible to use one process to meet its requirements, and it is necessary to use several processes to gradually achieve the required processing quality. In order to ensure the quality of processing and the rational use of equipment and manpower, the general production of parts can be divided into four stages: roughing, semi-finishing, finishing and finishing according to the nature of the process.
1. Rough machining stage. Its task is to remove most of the excess metal on the blank so that the blank is close to the finished part in shape and size. Therefore, the main goal is to increase productivity.
2. Semi-finishing stage. Its task is to make the main surface reach a certain precision, leave a certain finishing allowance, and prepare for the finishing of the main surface. And it can complete some secondary surface processing, such as reaming, tapping, milling keyway, etc.
3. Finishing stage. Its task is to ensure that the main surfaces meet the specified dimensional accuracy and surface roughness requirements. The main goal is to fully guarantee the processing quality.
4. Finishing processing stage. Surfaces with high precision and surface roughness requirements on parts need to be smoothed. The main purpose is to improve dimensional accuracy and reduce surface roughness. Generally not used to improve position accuracy.
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