What are the factors that affect machining errors?

2024-09-28 15:10:48

There are many factors that affect machining errors, and these factors can be roughly summarized as human factors, equipment factors, process factors and environmental factors. 1. artificial factors Inattention: When the operator is inattentive, it is easy to cause unnecessary mistakes, and in severe cases, it may even damage the machine tool or endanger life and safety. Errors in understanding: Incomplete understanding of the processing drawings or incorrect understanding of the processing requirements by the operator may lead to processing errors. Inexperience: Novice operators are prone to errors in the machining process due to lack of experience. Intentional error: a deliberate error by an operator for some personal reason, often with very bad effects. 2. equipment factors Errors of machine tools: The machining errors of machine tools mainly include spindle rotation errors, guide rail errors and transmission chain errors. These errors will directly affect the accuracy of the workpiece being processed. Spindle rotation error: caused by the coaxial error of the spindle, the error of the bearing itself, the coaxial error between the bearings, the spindle winding, etc. The error of the guide rail: caused by the manufacturing error of the guide rail itself, the uneven wear of the guide rail and the installation quality. Transmission chain errors: caused by manufacturing and assembly errors in the components of the transmission chain, as well as wear during use. Tool wear: The tool will gradually wear out during the cutting process, resulting in changes in the cutting size, which will affect the machining accuracy. Fixture error: The geometric error of the fixture has a great influence on the machining error (especially the position error). If the fixture positioning is not accurate or the clamping is not stable, it will lead to processing errors. 3.The process factors Improper setting of cutting parameters: Improper setting of cutting parameters such as cutting speed, feed rate, cutting depth, etc. will cause uneven cutting marks and affect surface quality. The processing sequence is unreasonable: the unreasonable arrangement of the processing sequence will also affect the processing accuracy and efficiency. For example, if roughing is performed first and then finishing is performed, but sufficient stress relief treatment is not performed after roughing, the workpiece may be deformed during finishing. Measurement error: During and after processing, if the measurement method is improper or the accuracy of the measuring tool is insufficient, it will lead to measurement error, which will affect the processing quality. 4.Environmental factors Temperature change: The change of temperature will affect the thermal deformation of the machine tool and the workpiece, thereby affecting the machining accuracy. Especially in precision machining and large machining, the machining error caused by thermal deformation can sometimes account for a large proportion of the total error of the workpiece. Vibration and air flow: Environmental factors such as vibration and air flow can affect the stability and accuracy of the machining process. For example, the vibration of the machine tool will cause the relative position of the tool and the workpiece to change, which will affect the machining accuracy. In summary, there are many factors that affect machining errors, and it is necessary to consider comprehensively and take corresponding measures to reduce the impact of these factors. For example, strengthen the training and management of operators, regular maintenance and repair of machine tool equipment, optimize cutting parameters and processing sequence, control the temperature and vibration of the processing environment, etc.