Cost comparison of maintenance policies

Maintenance is crucial to all repairable engineering systems as they will degrade and fail. The cost of maintenance for a manufacturing plant can occupy up to 30% of the total operating cost. If maintenance is not scheduled properly, unexpected equipment failure can induce significant cost due to reduced productivity and sub-standard products produced, both of which may result in customer penalty. Various maintenance policies have been proposed in the past. Among the various policies, age-dependent and periodic maintenances are the common policies employed in industries. Recently, predictive maintenance or condition based maintenance policies are also proposed owing to the advancement in the sensor technology. In this work, we compare the age-dependent and periodic maintenance policies as well as the predictive maintenance policies from the perspective of cost using Markov multi-state maintenance modeling and Monte Carlo simulation. To be realistic, imperfect maintenance is included, and both the sequential and continuous inspections are considered and compared.