Optimising maintenance intervals for multiple maintenance policies: a cross-industrial study

An approach for the optimisation of maintenance intervals is introduced, incorporating several distinct elements. First of all, Weibull analysis provides a generalisable means to estimate reliability of non-repairable products. Next, an optimisation model has been developed that employs maintenance interval length to optimise for cost under specific reliability and operational constraints. These constraints are derived from historical data to assure validity of the method for assistance in practical maintenance decision-making. The developed approach accounts for different types of failure regimes and incorporates the main three maintenance policies identified in literature (failure, preventive, and predictive), in contrast to existing methods. The applicability of the developed approach has been tested in three case studies, each describing application and results for a different type of industry and associated product. The results notify the user on the optimum interval time for inspection, where costs are minimised within an acceptable reliability range.