In CNC machining, process arrangement directly affects the final processing accuracy of parts. Through precision machining technology, the size, shape and surface quality accuracy of parts can be significantly improved to meet the stringent requirements of various industrial parts. The following will provide a detailed analysis of the impact of several key factors in the machining process on CNC machining accuracy to help companies better control processing quality and enhance product competitiveness.
1. Factors affecting the precision of parts due to processing technology

 Process route design A reasonable process route is the basis for ensuring the processing accuracy of parts. In the process route, the arrangement of the processing sequence has a direct impact on accuracy. Generally, the principle of "roughing first and then fineness, first primary and then secondary" should be followed in the process, that is, rough cutting is first performed to remove excess material (rough machining), and then high-precision finishing is performed. Reasonable process sequence can reduce residual stress and ensure dimensional and shape accuracy.

 Accuracy of tooling fixtures The selection and installation accuracy of tooling fixtures are directly related to the positioning accuracy of the parts. If the fixture is unstable or insufficiently accurate, it will cause slight displacement of the parts during processing, affecting the processing accuracy. In addition, the fixture conversion between different processes will also cause slight errors. Therefore, reducing process conversions and improving positioning consistency can greatly improve processing accuracy.

 Tool selection and wear control The geometric accuracy, wear resistance and service life of the tool have a significant impact on the machining accuracy. Tool wear will directly affect the shape of the cutting edge, resulting in machining errors. In order to ensure high precision, it is recommended to choose cutting tools with high wear resistance and high precision, and to check and replace them regularly. At the same time, the use of high-quality tool materials (such as carbide, ceramic materials, etc.) can also help reduce the impact of tool wear on machining accuracy.

 Setting of cutting parameters Reasonable settings of cutting speed, feed speed and cutting depth are important factors in controlling accuracy. Generally speaking, low cutting speeds and small feeds should be used during finishing to ensure surface quality and dimensional accuracy. At the same time, the cutting parameters are also related to the tool material, part material and the use of coolant. Reasonable parameter settings can reduce the force deformation of the tool and the thermal deformation of the part.

 The influence of cooling and lubrication systems Cooling and lubrication can reduce the heat and friction generated during the cutting process, control temperature rise, and prevent dimensional errors caused by thermal deformation of parts. During finishing, a good cooling effect can maintain a balanced temperature on the surface of the part, avoid thermal expansion and contraction during processing, and help improve surface and dimensional accuracy.

 Vibration control during cutting Vibration is one of the main factors affecting accuracy. During the machining process, the interaction of the machine, tool and workpiece generates vibrations, resulting in ripples on the machined surface and reduced accuracy. By increasing the rigidity of the machine tool, selecting appropriate cutting parameters, and using vibration-absorbing fixtures, the accuracy error caused by vibration can be significantly reduced.

2. Control method of machining accuracy

 Reserve sufficient machining allowance. The setting of machining allowance should take into account the deformation and residual stress of the part. By leaving enough margin in rough machining and further removing it in finishing to control the final size, the effects of stress and deformation are reduced and dimensional stability is improved.

 Adopting layered processing For high-precision parts, layered processing is an important method to improve accuracy. By removing material layer by layer, the stress on the material can be reduced, the impact of cutting heat can be reduced, and the final machining accuracy can be improved.

 Implement constant temperature processing For high-precision CNC processing, a constant temperature environment can greatly reduce the impact of temperature on processing accuracy. Especially for materials with large thermal expansion coefficients, maintaining a constant processing temperature can prevent dimensional changes caused by temperature fluctuations and improve accuracy and consistency.

 Use high-precision measurement tools for inspection. Use high-precision measurement tools (such as three-dimensional coordinate measuring instruments, laser interferometers, etc.) to detect part dimensions in real time, especially online inspection in key processes and the last process, to ensure the accuracy of each processing step. Accuracy, detect and correct errors early, and improve processing accuracy.

3. Summary

In CNC machining, every detail of process design will have an impact on part accuracy. Reasonable process routes, stable fixtures, high-quality tools, precise cutting parameters and good cooling effects are all keys to ensuring high-precision parts processing.