Precision part processing is impossible to complete all the processing contents of all surfaces in one process. The whole processing process of precision part processing can be divided into the following stages:
1. Roughing stage. Excavate most of the machining allowance for each machined surface and machine the fine reference, mainly considering increasing the productivity as much as possible.
2. Semi-finishing stage. Defects that may occur after roughing, in preparation for surface finishing, require a certain degree of machining accuracy, ensure proper finishing allowance, and complete secondary surface processing.
3. Finishing stage. At this stage, the large cutting speed, small feed rate and depth of cut are used to cut off the finishing allowance left by the previous process, so that the surface of the part can meet the technical requirements of the pattern.
4. Finishing stage. It is mainly used to reduce the surface roughness value or strengthen the machined surface, and is mainly used for surface processing with high surface roughness (ra≤0.32μm).
5. Ultra-precision machining stage. The processing precision is 0.1-0.01 μm, and the surface roughness value is ra≤0.001 μm. The main processing methods are: precision cutting, fine mirror grinding, precision grinding and polishing.