Boskalis Converts Windpiper into Major Subsea Rock Installation Vessel
Boskalis has completed the conversion of the Windpiper into a subsea rock installation vessel with a cargo capacity exceeding 45,000 tonnes, making it the largest vessel in its market segment. The project was supported by Vuyk Engineering, which delivered the basic design and engineering package for the extensive conversion.
Originally built for a different operational role, Windpiper has been transformed to support offshore rock installation activities, a critical service for offshore energy projects and subsea infrastructure protection. The vessel is designed to precisely place rock on the seabed for applications such as cable protection, pipeline stabilization, and offshore wind farm construction.
Advanced Fall Pipe Installation System
At the heart of the conversion is a tower-mounted inclined fall pipe system that guides rock from the vessel directly to the seabed. The system enables accurate rock placement, even in challenging offshore environments.
The cargo handling arrangement combines loading hoppers integrated within the vessel’s hull and feeder systems positioned above deck. Together, these systems transfer rock continuously into the fall pipe, ensuring a controlled and efficient material flow during installation operations.
To optimise bulk material handling, the cargo holds were redesigned around the operational needs of excavators and hopper systems. Several original compartments were combined and opened towards deck level, allowing direct loading and transfer of rocks into the installation system.
Extensive Structural Modifications
Vuyk Engineering carried out detailed structural engineering work to support the vessel’s new operational requirements.
The scope included engineering the modified cargo holds, the tower structure supporting the fall pipe system, and the associated under-deck support structures. Finite Element Analyses (FEA) were used to determine reinforcement requirements within the existing vessel structure, ensuring it could safely accommodate the significantly increased loads associated with large-scale bulk cargo operations.
In addition, stability calculations were performed to verify compliance with the operational requirements and regulatory criteria applicable to subsea rock installation vessels, including the integration of enclosed hopper systems within the hull.
Integrated Cargo Handling Design
A key aspect of the project was the development of a fully integrated general arrangement that aligned all cargo handling systems into a coordinated operational layout.
Hoppers, conveyors, and excavators were strategically positioned to maintain a continuous flow of rock from storage to installation. Interfaces between the systems were carefully engineered to maximise efficiency and ensure reliable operation during offshore projects.
Supporting systems, including overflow management and bilge arrangements, were also incorporated into the design, together with the associated piping infrastructure required for vessel operations.
Supporting Offshore Infrastructure Projects
The completed conversion has resulted in a purpose-built vessel capable of handling large-scale subsea rock installation projects. By combining high cargo capacity with advanced material handling and precise installation capabilities, Windpiper is positioned to support growing demand from offshore energy and marine infrastructure developments.
The project highlights the increasing role of vessel conversions in meeting the evolving requirements of the offshore sector, while also demonstrating how engineering expertise can extend the operational life and value of existing maritime assets.
Source: Vuyk Engineering / Boskalis.
