Research On Numerical Control Lathe Reliability Based On Fuzzy Theory

Numerical control lathes which plays a very important role in production and life is akind of mechanical and electrical products. Because of the complex configuration,severeworking condition,failure modes and failure cause of diversity, it is very necessary for faultinganalysis on the numerical control lathes and fault analysis is an important aspect in reliabilityassessment for numerical control lathes.This thesis deeply analyzed the fault data basing on the collected Numerical controllathes and made the reliability of numerical control lathe using the fuzzy mathematics theory.This thesis analyzed the production general numerical control lathe fault data of Yunnanmachine tool plant from three aspects of the failure mode,the cause of the problem and faultharm degree,found this series of numerical control lathe design of the weak link. Based on theabove analysis,this thesis deeply analyzed the subsystem of the fault frequent about the failuremode and the analysis of the cause of the problem,and CNC lathe tool system is the mostfrequent subsystem of the numerical control lathes fault,so we established the fault tree of thesystem fault of the top events. Through a preliminary analysis of the fault tree,we concludedthat all minimum cut set of the CNC lathes system fault tree,and utilized the triangular fuzzynumber to analyze the fault tree, and got the fuzzy probability of top tool of events fault. Thismethod overcomes the difficulties of traditional fault tree analysis in complex system,anddoes not reject traditional fault tree analysis method.According to the reliability of numerical control lathe,this thesis adopted the fuzzymathematics theory to evaluate the whole machine,and set up the evaluation model. Not onlyconsidering the various factors that influence the reliability but also making full use of experts,the evaluation result has certain objectivity.