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What are the general principles of fine mechanical parts processing? What is the order of processing? I believe this is a topic that all fine processing companies are very concerned about. In simple terms, it can be divided into four principles: benchmark first, division of processing stages, first face and then hole, and smooth processing.

1. Benchmark first

That is, the reference surface is processed first. During the machining process 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.

2. Divide the processing stages

Surfaces with high mechanical processing quality requirements are divided into processing stages, which can generally be divided into three stages: rough processing, semi-finishing and finishing. Mainly to ensure the processing quality of fine mechanical parts; facilitate the scientific application of equipment; facilitate the installation of heat treatment procedures; and facilitate the discovery of blank defects.

3. 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 accuracy of the plane and the position of the hole, and the processing of the holes on the plane is convenient.

4. Finishing

Finishing processing of the main surface, such as grinding, honing, fine grinding, rolling processing, etc., should be placed at the end of the process road. The general guidelines for drawing up fine parts processing technology roads and the formulation of fine parts processing technology regulations can be roughly divided into two links. The first is to draw up the process path of parts processing, and then confirm the process size of each process, the equipment and process equipment used, the cutting standards, and the quota of working hours.