Additive Manufacturing to Address Shipboard Supply Chain Challenges

Modern ocean-going vessels exist as complex systems-of-systems with multi-decade operational life cycles. Too often, robust supply chains established during a ship’s initial construction and commissioning begin to falter over time: sole-source vendors go out of business; part-specific materials can no longer be acquired; tools, molds, and other part-specific fabrication equipment are not maintained or retained; and skilled technicians retire or move on to new contracts. When a shipboard system fails at sea, the ship’s crew must now procure spare/repair parts that are scarce and/or obsolete, representing major supply chain challenges for today’s naval engineering community. Current approaches to mitigate these challenges include direct part cannibalization, whole-unit replacement, and production line restarts. However, additive manufacturing offers a new solution. This paper serves to broadly introduce the concept of additive manufacturing to address part scarcity/obsolescence and to highlight existing approaches within the United States Navy. Two representative shipboard parts are considered and presented: a T-shaped pull handle and a swing check valve gasket. These parts were systematically reverse-engineered, digitally modeled, printed, and tested. Ultimately, the entire process, from initial part identification to final certification, demonstrates the true complexity of additive manufacturing. Such complexity, as well as corresponding technological, economic, and cultural barriers, must continue to be investigated by naval engineers to better support related efforts in the greater maritime domain.