Mammoet has once again demonstrated its expertise in heavy lifting and transport, significantly optimizing the load-in process for transition pieces (TPs) at the Moray West offshore wind farm, located 22 kilometers off the coast of Scotland. This project, which aims to provide low-cost, low-carbon electricity to approximately 1.33 million homes, faced logistical challenges that required innovative solutions.
Initially, the plan was to utilize a Roll-on/Roll-off (RoRo) method for offloading the TPs. However, this method proved unfeasible due to constraints related to stowage plans, the arrangement of TPs on the delivery vessel, and the vessel’s mooring configuration. Mammoet proposed an alternative: transshipping the TPs onto Self-Propelled Modular Transporters (SPMTs) using a crawler crane. This approach offered greater maneuverability and reduced downtime between lifts, effectively mitigating the impact of shifting tides at the marshalling port.
Mammoet’s scope in this clean energy project involved receiving the components at the Port of Nigg after seaborne transport, offloading them onto SPMT trailers, and moving them to a temporary storage area for pre-installation work. Once ready for offshore delivery, the TPs were transported back to the quayside in batches of four, awaiting collection by an installation vessel.
Oliver Smith, Senior Commercial Manager at Mammoet, elaborated on the switch from the original plan: “New information about stowage plans and mooring arrangements meant the initial RoRo method was no longer viable. We adapted by redesigning the grillage and opting for a crawler crane solution, ensuring seamless transfer from ship to shore.”
The project featured two types of TPs: 60 units weighing approximately 505 tons each and two heavier Offshore Substation Platform transition pieces weighing around 832 tons. The LR11350 crawler crane, supported by a separate 24-axle line combination, lifted the TPs onto a 32-line SPMT configuration. This method allowed for the efficient maneuvering of the ballast tray, enhancing operational speed and safety.
Smith highlighted the efficiency of using SPMT transport: “Lifting the ballast tray by crane, especially with close to 600 tons of ballast, is time-consuming. The SPMT allowed us to move the load much faster, saving significant time.”
The TPs arrived at the port in varying batch sizes, creating logistical challenges, particularly when vessel delays occurred. Despite these hurdles, Mammoet’s team adapted quickly, ensuring that the schedule remained unaffected.
This project underscores the strong working relationship between Mammoet and its clients, built on years of successful collaboration. Smith emphasized the importance of this relationship: “Our experience and transparent engineering feedback enabled us to adapt plans swiftly, ensuring project completion on schedule. The trust and teamwork between us and the client were crucial to the project’s success.”
Mammoet’s ability to innovate and adapt in the face of logistical challenges has once again proven essential in advancing clean energy projects. Their crane and SPMT solution for the Moray West offshore wind farm is a testament to their commitment to efficiency and safety in heavy lifting and transport operations.
