Preventive maintenance policy for life-type equipment

To solve the problem of economic maintenance policy of life-type equipment under Preventive Maintenance(PM) based on reliability,a method of solving the policies of maintenance cycle and maintenance time was proposed.Concretely,based on reliability theory,maintainability was used to describe the percent of unreliability's reduction caused by maintenance,taking equipment's reliability and maintainability obeying exponential distribution for an example,and failure rate increase factor and repair rate reduction factor were introduced,some equations were established to define the relationship of reliability and maintenance cycle,and maintenance time;Based on the equations and taking total income in equipment's life as the objective,the policy model of preventive maintenance cycle and preventive maintenance time for life-type equipment was established.Finally,preventive maintenance policies with different parameters were obtained by optimization calculation.The results showed that the preventive maintenance cycle and preventive maintenance time of life-type equipment increased at first and decreased later,and the higher maintenance cost the less maintenance times and time.