Consolidating spare parts for asset maintenance with additive manufacturing

Abstract Consolidation of parts is the redesign of an assembled component with fewer, but therefore more complex parts. While complex parts are often difficult to produce with conventional manufacturing (CM) technologies, the high degree of design freedom of additive manufacturing (AM) facilitates consolidation. Typically, consolidation with AM is chosen because of its functional benefits such as weight reductions. Consequences for asset maintenance, however, are not that well understood. For example, the spare parts management may profit from potentially shorter AM resupply lead times, but may suffer from more expensive consolidated parts having to be stocked in anticipation of random failures. In this paper, we analyze the total costs of consolidation with AM, including logistics, manufacturing and repair costs. Our results suggest that consolidation with AM often leads to higher total costs. This finding mainly stems from loss of flexibility. For example, in case of a failure, a consolidated component has to be replaced entirely whereas the conventional assembled component might only require replacement of a defective sub-component. Furthermore, short resupply lead times for the consolidated spare part turn out to have little impact and therefore relativize the benefit of consolidation with AM. Overall, these findings stress the necessity to adopt a total costs perspective when assessing the effects of design changes with AM. Otherwise, design changes may lead to unforeseen effects which may render its application debatable, even despite substantial functionality improvements.