Optimisation of pipe system routing and space reservation in ship design with regard to production cost drivers

Abstract

Piping systems account for nearly half of all detailed engineering time in shipbuilding and exert a dispro- portionate influence on total production costs. In the competitive Engineering-to-Order (ETO) market, where profit margins typically lie between 2 and 6%, labour efficiency during pipe installation repre- sents a far greater cost lever than material savings alone. Yet existing Automated Pipe Routing (APR) algorithms optimise almost exclusively for material reduction (minimising pipe length and the number of bends), while largely neglecting ease of installation as a design objective. This thesis addresses that gap by proposing a combined methodology that integrates production cost drivers directly into the pipe routing and space reservation process during the design phase. The approach proceeds in three stages. First, Value Stream Mapping (VSM) is applied to the pro- duction process at Damen Offshore Specialised Vessels (OSV), identifying installation as the primary bottleneck by non-value-added duration. Second, Fuzzy Logic (calibrated through expert question- naires with ten industry specialists) translates physical clearance distances around pipes into a quan- titative Installability Index (II) and Time Multiplier (TM), bridging the gap between vague engineering descriptions and the crisp numerical inputs required for algorithmic optimisation. Third, these metrics are embedded as penalty terms within an 𝐴∗ pathfinding algorithm that simultaneously enforces Classi- fication Society hard constraints governing hazardous zone separation and vertical routing restrictions. The methodology is tested in a case study on the engine room of the Windcat Amsterdam, a CMB.TECH vessel built by Damen. Rerouting key pipe systems yielded a theoretical 18% reduction in installation time, corresponding to a potential saving of 12,498 man-hours for a single engine room. These results demonstrate that installation-aware routing is a practically achievable and financially meaningful improvement to current design practice.