Component Redesigns and The Impact of Their Implementation Policy

An OEM who maintains a fleet of complex systems strives for high system availability for its customers. Frequently failing components lead to system unavailability and high maintenance costs. Consequently, the OEM might decide to upgrade components. We develop a model that quantifies the impact of the introduction of an upgraded component on the OEM's costs and number of failures to define the best implementation strategy. Using a Markov process, we evaluate four policies differing in the roll-out strategy of new parts, either immediate or corrective, and the phase-out strategy of old parts, either rework or salvage. The model is used in a case study at ASML. We conclude that, in the case study, reworking is preferred over salvaging as the phase-out strategy and corrective replacements are generally preferred over immediate replacements for the roll-out strategy.