Reliability Allocation Of CNC Lathe Based On Relevant Classes

The reliability level of the numerical control equipment affects directly the development ofthe manufacturing industry in our country, so it is very urgent to improve its reliability. As animportant part of reliability design, Reliability allocation is an important analytical tool toimprove the inherent reliability, and the reasonable and effective reliability allocation has aguiding significance for reliability design.This paper based on the number of CNC lathe faults, breakdown maintenance stoppingproportion, subsystem reliability effect and subsystem organization complexity as theinfluence factors of reliability allocation. The correlation failure are divided into great relatedclasses in solving the subsystem reliability subsystem, and get the reliability function througheach subclass subsystem modeling, making the reliability effect more reasonable and effective.And calculate the weight of each reliability influence index by Entropy method, to obtainweight proportion of all the factors. Carry on reliability allocation of CNC lathe on the basis ofit.This paper firstly divides subsystem according to the composition and working principle ofCNC lathe, and builds up the fault related mathematical model considering on failurecorrelation and fault causal analysis of failure data. Draw CNC Fault Correlation Graph andtranslate into adjacency matrix, using the time characteristics and laws of Boolean algebra tosolve reachable matrix, decomposition of matrix to realize decoupling, to obtain relatedclasses of CNC lathe fault, and its great as the basis of reliability modeling; Second,considering the impact of multiple truncation data, the mean rand order was used to modifiedconsidering the time related. Use the mean rand order to modified the order of failure data.model parameters are estimated by least square, and test of reliability model by the correlationcoefficient and d inspection, to get the reliability of the whole machine and the subsystemmodel and subsystem reliability function, and provide the basis for reliability allocation.Finally, based on the principle of reliability allocation, calculate the weight of each reliabilityinfluence index by Entropy method, to obtain weight proportion of all the factors, and theresults combined with the distribution of the target assign to each subsystem, to realize thereliability allocation task of CNC lathe.