We divide mechanical processing into the following four stages:

One, face before hole

For parts such as box body, bracket and connecting rod, the plane should be processed first and then the hole should be processed. In this way, the holes can be positioned on the plane to ensure the position accuracy of the plane and the holes, and it is convenient to process the holes on the plane.

Second, process the datum surface first

During the processing of the part, the surface as the positioning reference should be processed first, so as to provide a precise reference for the subsequent processing as soon as possible. This is called “benchmark first.”

3. Finishing

The finishing processing of the main surface (such as grinding, honing, fine grinding\rolling processing, etc.) should be carried out at the last stage of the process route. The surface finish after processing is above Ra0.9um. A slight collision will damage the surface. In Japan , Germany and other countries, after finishing processing, must use flannel for protection. Never directly touch the workpiece with your hands or other objects to avoid damage to the finishing surface due to transfer and installation between processes.

Fourth, divide the processing stage

Surfaces with high processing quality requirements are divided into processing stages, which can generally be divided into three stages: rough processing, semi-finishing and finishing. The main purpose is to ensure the processing quality; facilitate the rational use of equipment; facilitate the arrangement of the heat treatment process; and facilitate the discovery of blank defects.