The Failure Mode Analysis Of Machine Center In Random And Random-fuzzy Conditions

The fault analysis of CNC machine tools is not only one of the most important aspects of the reliability research of CNC machine tools, but also an important means to improve the reliability. It is essential to do the in-depth and accurate analysis of CNC machine tools failure data, in order to find out the inherent law of the fault and to control the fault effectively; farther,the author bring forward some fundamental measures to reduce or avoid the probability of the fault occurrence, then the reliability of CNC machine tools get improved.In this paper, fault data and information of a series of Machining Centers are collected. Based on "the reliability of field test norms", the data are analyzed seriously. The statistical analysis of the fault mode, fault components, fault causes about the machine center were done, Analyze the typical fault modes under the random conditions and the random-fuzzy conditions.1. Fault mode, fault components, fault causes analysis of machining centerThe study of statistical analysis was made based on classification of failure mode, fault components and fault causes in this paper. Investigate the frequency of the whole of the failure mode, fault components and fault causes, dig out the occurrence of the fault overall machine center of this series the.Identify the most significant failure mode of machine center is the disorders of knife library, the frequent fault component is knife library, and the main cause of failure is concentrated on the damaged parts. These statistics conclusions can be used as failure analysis and design to improve the reliability of machine center, as well as providing the basis for the further study.2. The fault mode analysis of machine center in random conditionsThe fault mode analysis of machine center in random conditions was made in this paper. First of all, the typical failure mode was calculated the separate time between failures and the parameters was estimated based on the application of one model \ one mechanism \ one function, finally get the probability distribution function and probability density function the typical fault mode.Based on the functions, the analysis of the typical failure mode was done, obtaining the characteristics of the occurrence, the failure mechanism and the law of the occurrence of fault mode.The reliability indexes of the typical failure modes of machine center were respectively obtained, providing a theoretical basis for the repair and maintenance of machine centers. In addition, the foundation was made for a further study of he random-fuzzy analysis of fault mode study of machine center.3. The fault mode analysis of machine center in random-fuzzy conditions.The further study about the random-fuzzy analysis of the fault mode was made in this paper, based on the random analysis of fault mode study. The occurrence of the fault is accompanied by the double uncertainty, the random and the fuzzy, which raising the question of the random-fuzzy analysis of the fault mode of machine center. The model about the opportunity of occurrence about the fault mode was set up. The contents of random fuzzy variables were applied when the typical fault modes were made, in order to overcome the problem of the random uncertainties separately considered. The process of random-fuzzy simulation was made by MATLAB, calculating the results of the opportunity of occurrence about the fault mode, which were sorted. Compare the sequence with the frequency of the fault mode, obtaining the reasons causes of this sequence, which is more objective. The conclusion of the max opportunity about the occurrence of the fault mode is the damage parts, which is focused on the fault mode for the effective prevention. The foundation was set for this series of machine center by the analysis of the random-fuzzy.