A TBE control chart-based maintenance policy for a service facility

In service industry, malfunctioning or failure of service facilities commonly occur due to environment-related factors. Such malfunctioning or failure is usually handled by resetting the system to avoid interruption of service. However, maintenance is needed if there is system degradation which may cause failure to occur more frequently. As system degradation is not self-announced, whether a simple resetting action or maintenance is needed to address a failure is critical. In this paper, a condition-based maintenance (CBM) model for service facility is established. The maintenance model determines whether maintenance is needed by monitoring the time between failure occurrences with a TBE (Time Between Events) control chart. The service queueing system is formulated as a Markov chain, with which the steady-state costs of the system can be obtained and minimized. Numerical experiments show that the proposed maintenance model yields significant cost saving compared to the model without using TBE control chart. The effects of system parameters on both the optimal policy and cost saving are discussed.