In order to ensure the machining accuracy, rough machining and finish machining shall be carried out respectively. During rough machining, a large number of workpieces are subject to cutting force, clamping force and heat, which is easy to cause surface hardening, and there is a large internal stress in the workpiece. If the finishing and rough machining are continuous, the precision of precision parts will be redistributed with the stress after finishing, and will be lost soon.

For some parts with high machining accuracy. Low temperature annealing or aging treatment shall be carried out after rough machining and before finishing to eliminate internal stress.

Reasonably select machining equipment. The main process of rough machining is to cut off most of the machining allowance, which does not require higher machining accuracy. Therefore, roughing machine tools only need high power and low precision machining. Finishing requires more sophisticated machine tools. Rough and finish machining on different machine tools can not only give full play to the performance of the equipment, but also prolong the service life of precision machine tools.

Heat treatment is often required in machining. The arrangement of heat treatment process is as follows: in order to improve the cutting performance of metal, such as annealing, normalizing, quenching and tempering, it is usually carried out before machining. In order to eliminate internal stress, such as aging treatment and quenching and tempering treatment, it is generally carried out after rough machining and before finishing machining. In order to improve the mechanical properties of parts, carburizing, quenching and tempering are generally carried out after machining. If there is deformation after heat treatment, the final processing procedure must be arranged.

The production process of precision machining refers to the whole process of manufacturing products from raw materials (or semi-finished products). It is used in machining production, including transportation and preservation of raw materials, production preparation, rough machining, parts processing and heat treatment, product assembly and commissioning, painting and packaging.

1. From the perspective of hardware, the machining of mechanical parts is carried out through a variety of mechanical equipment, such as automobile, milling machine, planer, grinder, broaching machine and machining center. The inherent machining accuracy of various equipment is different. Therefore, in order to achieve a certain accuracy, it is necessary to select appropriate machining process and machining equipment during working hours.

2. In terms of software, it is an operator's technology, which involves the operation skills of various equipment operators. These skills include a thorough understanding of equipment, machining, parts and materials. These skills can be gradually accumulated in daily work