For precision parts, the processing is very strict, and the processing procedures include cutting in and out. There are specific requirements for size and accuracy, such as 1mm plus or minus micrometers, etc. If the size is too large, it will become scrap or declare the blank scrapped. At this time, it is equivalent to reprocessing, which is time-consuming and laborious, and sometimes even makes The entire processing material is scrapped, which causes an increase in cost, and at the same time, the parts are definitely unusable.

(1) In order to ensure the machining accuracy of precision parts, the machining of rough and fine mechanical parts is best carried out separately. Because of the large amount of cutting when machining rough mechanical parts, the workpiece is subjected to large cutting force, clamping force, heat generation, and the surface of the mechanical parts has a significant work hardening phenomenon, and there is a large internal stress inside the workpiece. If the machining of rough and rough mechanical parts is carried out continuously, the precision of the parts after finishing will be quickly lost due to the redistribution of stress.

(2) Reasonable selection of equipment. Rough machining of mechanical parts is mainly to cut off most of the machining allowance, and high machining accuracy of mechanical parts is not required. Therefore, the rough machining should be carried out on a machine tool with high power and low precision, and the finishing process requires high Precision machining.

(3) In the processing route of precision parts, heat treatment processes are often arranged. The position of the heat treatment process is arranged as follows: In order to improve the cutting performance of the metal, such as annealing, normalizing, quenching and tempering, etc., it is generally arranged before the machining of the mechanical parts.