Precision control of CNC parts machining is the key link in CNC machining, which directly affects the quality and performance of products. The following is a detailed description of the machining accuracy control of CNC parts from many aspects:
First, the selection and maintenance of machine tools and tools
1. Machine tool selection:
– CNC machine tools with stable performance and high precision should be selected. The positioning accuracy, repeated positioning accuracy and transmission accuracy of the machine tool have an important impact on the machining accuracy.
High-performance CNC machine tools usually have higher positioning accuracy and repeated positioning accuracy, which can reduce machining deviations caused by machine errors.
2. Tool selection:
The quality, geometry and wear of the tool have an important impact on the dimensional accuracy of the machining.
– Appropriate tool materials and tool geometry parameters should be selected to adapt to different machining materials and processing requirements. For example, when processing materials with higher hardness, carbide tools or ceramic tools can be selected; For high-precision machining, small diameter, sharp tools can be used.
– Check the wear of the tool regularly, replace the worn tool in time, and avoid the machining size error caused by the tool wear.
3. Maintenance of machine tools and tools:
– Regular maintenance and maintenance of machine tools and tools, such as cleaning machine tools, lubricating moving parts, checking electrical systems, etc., to keep them in good condition.
– Perform regular calibration and maintenance of tools to ensure their accuracy and reliability.
Second, the setting and optimization of process parameters
1. Cutting speed, feed rate, cutting depth and other process parameters:
– The selection of these parameters requires comprehensive consideration of machining materials, tools, machine tool performance and other factors. Through experiment and simulation analysis, the optimal combination of process parameters was determined.
– Under the condition that the rigidity allows, a larger cutting depth can be selected during roughing to reduce the number of tool trips and improve the processing efficiency; When finishing, a smaller cutting depth is generally taken to ensure the machining dimensional accuracy.
2. Temperature control:
– The heat generated during the machining process will cause the thermal deformation of the machine tool and the workpiece, thus affecting the machining dimensional accuracy. Therefore, it is necessary to take effective temperature control measures, such as cooling systems, constant temperature workshops, etc., to reduce the impact of temperature changes on processing accuracy.
– At the same time, the thermal compensation technology is used to compensate the machining dimensions in real time according to the temperature distribution of the machine.
Third, programming and control system optimization
1. Programming optimization:
– Adopt reasonable processing technology and tool path to reduce unnecessary processing actions and improve processing efficiency.
– Ensure machining accuracy through accurate calculation of tool compensation and machining parameters.
– Flexible use of the main program and subroutine, repeatedly calling the subroutine in the main program to ensure the consistency of the processing size.
– Programming in an absolute manner reduces the cumulative error of the CNC system.
2. Control system optimization:
– Choose advanced CNC system, use adaptive control function to adjust parameters in real time during the machining process to adapt to changes in material hardness or unexpected circumstances.
– Calibrate and maintain the CNC system regularly to ensure its stability and reliability.
Fourth, measurement and feedback mechanism
1. High precision measurement system:
CNC machine tools are usually equipped with a variety of measuring systems such as grating ruler, encoder, etc., which are used to accurately feedback the position information of the moving parts of the machine tool in real time to provide accurate data support for the control system.
– Regularly calibrate and maintain the measuring system to ensure its accuracy and reliability.
2. Machining error measurement and feedback:
– Adopt advanced testing means to detect and measure parts during and after machining to find and correct machining errors in time.
– Adjust the programming and machining parameters according to the measurement results to ensure the effectiveness of precision control.
Fifth, operator training and management
1. Skill improvement:
– Strengthen the training and education of operators to improve their skill level and operational experience. Improve machining accuracy and efficiency by mastering CNC programming, machine tool operation and tool selection knowledge.
2. Quality awareness training:
– Cultivate the quality awareness of the operators so that they can process in strict accordance with the operating procedures and find and solve problems in time.
– Encourage operators to participate in quality improvement activities to promote machining accuracy.
To sum up, the precision control of CNC parts processing needs to start from the selection and maintenance of machine tools and tools, the setting and optimization of process parameters, the optimization of programming and control systems, the measurement and feedback mechanism, and the training and management of operators and other aspects of comprehensive use of various technical and management means to meet the increasing requirements of manufacturing accuracy.
