PSI - Issue 79

Suzana Lampreia et al. / Procedia Structural Integrity 79 (2026) 81–87

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ships, but to maintain that redundancy some spare parts from electro-pumps or even complete substitute electro-pumps should exist on board. One example of spare parts that should exist on board should be impellers, shafts, housing. If the concern is the spare parts for old and obsolete ships, AM may be an expedite solution. To conceive a pilot electro-pump maintenance system with AM strategy there should exist some steps to follow:  Part selection criteria  Material and process matching  Digital library preparation  Printing and verification  Deployment model  Performance metrics To start the implementation of a maintenance based on AM at first the spare parts selection should be based on moderate complexity, manageable size, moderate to high criticality, and limited historical demand (ex.: impeller prototypes and rubber gaskets). Then the material match between mobile parts should be verified, and if it is the case use metal AM (e.g. SLM or DED) with suitable alloys (e.g.: stainless, Monel for corrosion resistance); for gaskets, polymer compatible AM may suffice. For the digital library the use of reverse-engineer or obtain CAD models; optimize design with for AM modelling techniques, topology optimisation, part consolidation, lattice infill to improve durability and reduce material use. For printing and verification, it should be conducted pilot printing, followed by mechanical testing (tensile and fatigue), geometric alignment, and surface finish evaluation. The deployment model on the ship should be a containerised AM station or port based workshop supplying multiple warships, retain dual sourcing with OEM when available. And then perform metrics to track lead-time to delivery, cost comparisons, part performance, downtime saved and safety outcomes.

Fig. 3. Proposal methodology for applying 3D printers on equipment´s maintenance on board ships.

On Fig. 3. can be observed a methodology for implementing 3D printers on equipment´s maintenance on ships. The first step is to choose the electro pump, follow by preparation of database with the spare parts designs, then chose the 3D metal printer suitable for install on board ship, proceed to post print treatment, then test and evaluate 3D produced spare parts, and if the quality is acceptable apply the produced spare parts on the electro pump or storage on a proper space. If the quality is not acceptable go to the spare part designs database and check the designs and re-do