Large neighbourhood search for coil stowage planning with pallet sequencing considerations

The coil stowage problem in ship loading is a critical factor affecting logistics efficiency in the steel industry. Despite its operational significance, research on optimising coil stowage sequences remains limited. This study proposes a mathematical model and a large neighbourhood search algorithm to jointly optimise the positioning and sequencing of coils. As coils are typically transported on pallets from warehouses to a loading dock, and the dock can accommodate only a limited number of pallets, optimising the loading sequence can significantly reduce the frequency of costly and time-consuming pallet recalls. The proposed approach improves overall stowage efficiency. The algorithm was validated using real-world industrial data, demonstrating its practicality and effectiveness. Performance evaluations showed that the proposed method outperformed the comparative methods in most tested instances, particularly in sequence optimisation. This study provides valuable insights and a practical solution for enhancing logistics efficiency in coil stowage operations within the steel industry.