Failure Analysis of Economic CNC Machine
Abstract
This article focuses on the problems and causes of the failure of economic CNC machines, and analyzes and evaluates the possible failure causes from four aspects of machine tool, material and processing technology, numerical control system and environment. Through the analysis of the wrong result samples, the corresponding preventive and corrective measures are proposed in combination with the characteristics of the economic CNC machine, so as to improve the machining accuracy and promote the development of economic CNC machine.
Key Words
economic CNC machine, failure analysis, preventive and corrective measures
1 Introduction
Machine tools and numerical control technology have developed rapidly in recent years. The rapid development of this two technology makes the economic CNC machine closely connected with the production. Therefore, it is necessary to analyze the reasons of economic CNC machine failure in order to reduce production costs and improve production efficiency.
2 Failure Causes Analysis
2.1 Machine Tool Reasons Analysis
Machine tool prevention and maintenance is an effective way to reduce economics CNC machine tool failure rate. The accurate operation of CNC machine tools depends on the stability of the machine tools itself. therefore, the installation of the economic CNC machine must be strictly controlled, and the numerical control system, tool setting and other settings should be checked after the installation is completed. At the same time, the machine tool should be inspected before each start-up. The oil should be added and the lubrication of all parts of the machine tool should be ensured to ensure the stable operation of the machine tools.
2.2 Material and Processing Technology Reasons Analysis
Economic CNC processing technology has errors due to improper selection of materials and processing processes. The mechanical properties and other characteristics of the materials have a certain influence on the machining accuracy. When choosing materials, the characteristics of the materials, such as tensile strength, hardness and elasticity, are studied. The less elastic materials should be selected for the required parts. In addition, it is necessary to select the corresponding processing technology and process parameters in accordance with the correctness of materials and machining accuracy. The cutting parameters of economic CNC machine tool should be adjusted to ensure that the cutting tool can penetrate the surface of the workpiece smoothly.
2.3 Numerical Control System Reasons Analysis
The failure rate of economic CNC machines numerical control system is also high. The numerical control system should be debugged according to different sparams before each start-up. The parameters of the numerical control system hav important influence on the processing accuracy and efficiency. If the parameter settings are incorrect in the numerical control system, it is likely to result in the failure of the economic CNC machine system. The software should be updated regularly as well as the comprehensive diagnosis of numerical control system should be conducted from time to time.
2.4 Environment Reasons Analysis
The environment conditions also have some effects on the accuracy of economic CNC machine processing. Economic CNC machine should be used in environment with stable humidity, temperature and air pressure. Normally it is not suitable to process in the environment with large temperature fluctuation and large dust, otherwise the accuracy of economic CNC machine processing will be affected.
3 The Wrong Result Sample Analysis
After analyzing the possible causes of the failure of economic CNC machines, we can analyze the wrong samples. The wrong result samples are mainly divided into two categories, which are large and small errors. Large errors mainly refer to deformation of the workpiece after processing, while small errors generally refer to geometric errors.
3.1 Large Errors
The main reason for the large error of economic CNC machine is the thermal deformation. The temperature of the machine tools will rise in the CNC processing, and the temperatu will continue to rise after the cutting head leaves the workpiece surface. If the compensation of temperature rise is not timely, the deformation of the workpiece will be caused, thus leading to a large error.
3.2 Small Errors
The main reasons for small errors are tool wear, operator operation mistakes and incorrect tool data. Operator operation mistakes will lead to incorrect numerical control parameters and incorrect tool data, which will eventually cause small errors. Tool wear increases with the prolongation of the CNC processing time. With the increase of the cutting speed, the blade wear becomes serious, and the abrasion weakens the cutting force of the blade, which will eventually cause the dimensional error of the workpiece.
4 Conclusion
From the analysis on the failure causes of economic CNC machine tool above, we can conclude that the preventive measures should be taken from four aspects of machine tool, material and processing technology, numerical control system and environment. The selection of cutting tools and the adjustment of cutting parameters should receive attention for the thermal deformation of the workpiece. The operator should strictly follow the established operating procedure to avoid operator operation mistakes. Finally, the regular comprehensive diagnosis of the numerical control system and the environment should be conducted.
5 Acknowledgements
This work was supported by the National Natural Science Foundation of China (Grant No. 61902766).
