Modelling Preventive Maintenance of Production Plant Given Estimated PM Data and Actual Failure Times

Using the delay time maintenance modeling theory, this paper is concerned on a modelling study of optimising the preventive maintenance interval of a production plant. The model developed is fitted to the maintenance data of recorded failures and the estimated number of defects identified at preventive maintenance (PM). Firstly, the parameter values of the process by which defects arise and of the delay time distribution are estimated using the method of the maximum likelihood. Secondly, a PM model is proposed to describe the relationship between the total downtime and the PM interval. Finally, an optimal inspection interval of PM is identified, which is based upon the estimated model parameters and the PM model