How to develop a machining route

As a prototype manufacturer, we have advanced CNC equipment, and we are very good at machining workpieces with complex structures. Before the workpiece is put on the machine, engineers usually simulate the machining process route, and the following principles are followed: 1. The principle of formulating the process route of machined parts
During the machining of the part, the surface used as the positioning reference should be machined out first, so as to provide a reference for the processing of the subsequent process as soon as possible.
2. The principle of dividing the machining process route of the processing stage
When processing surfaces with high quality requirements, processing stages are usually divided, which can generally be divided into three stages: rough processing, semi-finishing and finishing. This is done mainly to ensure the quality of processing; Increase the reasonable utilization rate of machine tool equipment; It provides convenience for the arrangement of heat treatment processes; and facilitate early detection of blank defects.
3. The principle of machining process route of first face and then hole
For parts such as housings, brackets, and connecting rods, the plane should be machined before the hole. In this way, the hole can be machined in a plane position, ensuring the position accuracy of the plane and hole, and bringing convenience to the processing of the hole on the plane.
4. Photofinishing should be arranged in the final stage of the machining process route
The smooth finishing of the main surface, such as grinding, honing, fine grinding, rolling processing and other machining processes, should be carried out in the last stage of the machining process route. When the surface roughness of the workpiece after processing is lower than Ra 0.8, the slightest collision will damage the surface. After the workpiece is light-finished, it is usually not allowed to directly contact the workpiece with hands or other objects, so as not to damage the surface due to the transfer between processes and the installation between workpieces.

After introducing the general situation of the machining process arrangement, and then introducing some specific situations, it can be handled according to the following principles.
Things to consider when developing a machining route
1. Consider that roughing and finishing are carried out separately
Because the workpiece is rough machining, the cutting amount of the tool is very large, the workpiece will bear a lot of cutting force and clamping force, the workpiece surface will produce a lot of heat, resulting in a more significant work hardening phenomenon on the surface of the workpiece, then there will be a lot of internal stress inside the workpiece. If the rough and finishing is carried out continuously, the internal stress of the finished part will be redistributed, which will cause the dimensional accuracy of the workpiece to be out of tolerance. For some parts that require high precision, low-temperature annealing or aging processes are usually scheduled after roughing and before finishing, which can eliminate the internal stress of the part. 
2. Consider the reasonable selection of equipment
Roughing is mainly to cut off the machining allowance of the workpiece, and the requirements for machining accuracy are not very high, so roughing should be carried out on a machine tool with greater power and not too high precision. The finishing process requires high machining accuracy of the machine tool. Roughing and finishing are arranged for processing on different machine tools, which can not only give full play to the equipment capacity, but also extend the service life of precision machine tools.
3. In the machining process, heat treatment processes are often arranged
The arrangement of the location of the heat treatment process can be referred to as follows: (1) annealing, normalizing, tempering, etc. before machining can improve the cutting performance of the metal; (2) Aging treatment, tempering treatment, etc. after rough machining can eliminate the internal stress of the workpiece and carry out before finishing; (3) Carburizing, quenching, tempering, etc. after machining can improve the mechanical properties of parts. If the workpiece undergoes a very large deformation after heat treatment, the final processing process needs to be arranged next.
summary
When formulating the machining process of parts, due to the different types of production of parts, the processing methods, machine tools, clamping measuring tools, blanks and technical requirements for workers are very different.