The Maintenance Peplacement Of A Component And Cold Standby Systems

With the rapid development of science and technology,the era of mechanization is coming,and the maintenance problems of the components are also concerned.Up to now,researchers study a single component system,a cold system and a series parallel system.In the fact,the single component system is foundation of others repairable systems and most researchers focus on the cold standby system.Therefore,depending on the related literature,the theory of updating process,geometry process and alpha power process is used to analyze the replacement policy of single component and cold systems.Firstly,we study a repairable system of a single component with the repairman taking vacations and the maintenance time restricted.To the system,we take preventive maintenance and fault repair as the mixed maintenance strategy and assume that the system is taking preventive maintenance with “as good as new” and the working life and maintenance time of the component obey exponential distribution.If the repair is not completed in the given limit repair time ?,we will replace the new system.Using mathematical theory,such as the geometric process and renewal process theorem,we establish a optimization model of three dimensional maintenance replacement strategy with preventive maintenance interval T and component failure frequency N,which regards the vacation time as objective function subjecting to the cost ratio.Finally,the existence of optimal policy is demonstrated by the numerical example.Secondly,we set a cold system as the research subject,made up of two different type components.Considering the priority,the repairman with vacation and limited reliability,we assume that the preventive maintenance time rely on the reliability R.We set the fault number N and preventive maintenance interval nT of component 1 as two-dimensional parameter,asset the ratio of cost and the average downtime as constraint conditions,and enumerate function expressions of the dependent variable for vacation time.Depending on some known parameters,we get the corresponding numerical results of the tradeoff model,pick out the optimal value for the objective function,and verify the feasibility and effectiveness of the results.Finally,we also set the cold system as the research object,and make the following changes based on the research content in the last chapter.We not only use the alpha power process to fit the life distribution and repair process of components,but also set the preventive maintenance interval of components as a regular basis.Under these assumptions,we establish a function with the fault number and preventive maintenance time interval,and set the system average downtime as a constraint condition.Finally,we give special parameter value which is suitable for the limited solution of the model,and get the optimal value.