An integrated production and preventive maintenance planning model with imperfect maintenance in multi-state system

Production planning and maintenance are two important problems in manufacturing systems. Despite the relationship exists between these two problems due to sudden failures and production capacity occupied by maintenance activities, each of these problems planned separately and as a result program and model efficiencies reduce in the real world. The aim of integrated production and maintenance planning models is to plan production and maintenance simultaneously due to the interaction of these two programs on one another. In this study, an integrated model is provided for planning production and preventive maintenance in a multi-state system. This model can be used to determine the production planning variables such as time to setup, the levels of production, inventory and shortages simultaneously with maintenance planning variables such as time and type of preventive maintenance. This research considers the concept of imperfect maintenance in modeling the preventive maintenance variable. At the end, a numerical example is used to assess the performance of the model. It is shown that using proposed model with two type of preventive maintenance will reduce the total cost of the integrated problem.