Harlyn, a leader in marine logistics and offshore support, has successfully completed the mobilisation of JD-Contractor’s, JD Assister for Enshore Subsea, facilitating the 3,200-mile transatlantic transport of the state-of-the-art T3200 trencher from the Port of Blyth, UK, to the United States in August 2024. The trencher played a pivotal role in a major offshore wind farm development, underscoring the growing global demand for advanced subsea cable installation technology.
The 170-tonne T3200 trencher, essential for hard ground trenching operations, was carefully mobilised along with its associated spread, including control rooms, generators, scissor frame, stores, and a Passive Heave Compensator. The mobilisation required meticulous planning and execution to ensure efficiency and safety throughout the process.
Harlyn leveraged Enshore Subsea’s deck plan and steelwork to manage every phase of mobilisation, from preassembly to testing. This encompassed a wide range of critical tasks, including:
- Hotworks and lifting operations
- Planning and execution of QHSE site management
- Coordination with hydraulic and electrical subcontractors
- Comprehensive risk assessments and safety checks.
Given the complexity of the operation, the Harlyn team built flexibility into the plan, allowing for real-time adaptations to dynamic project challenges. The mobilisation process involved multiple complex lifts, including the installation of heavy equipment and the combined lifting and skidding operation for the Passive Heave Compensator installed with less than 100mm clearance around the 12m long piece if equipment.
‘Our team of engineers and subcontractors work safely and efficiently to perform this slick mobilisation, dealing with the inevitable clashes and challenges every mobilisation encounters. But with a great client and vessel interaction the operation was completed successfully’ – H.Adamson Managing Director, Harlyn,
To support seamless execution, Harlyn contracted specialist partners and maintained multiple cranes and personnel to maximise uptime for lifting, hotworks, and electrical work. This strategic approach allowed for adaptable resource management, ensuring that all project risks were managed safely and effectively.
With the trencher successfully delivered to the United States, it played a vital role in the offshore wind farm development, marking another milestone in the global shift towards sustainable energy solutions.
Following the completion of its scope in the US, the JD Assister returned to the Port of Blyth, where Harlyn undertook the demobilisation process. During early March the T3200 trencher and its supporting infrastructure were unloaded, bringing the project to a successful conclusion.
James, a graduate in Mechanical Engineering from Newcastle University, began his career at Harlyn in the summer of 2024 after meeting the team at the Newcastle University Careers Fair. Drawn by the opportunity to collaborate with a talented and close-knit group of engineers, he saw Harlyn as the perfect environment to grow as a professional. James has been involved in a variety of impactful projects, quickly applying his academic knowledge to real-world challenges. One of his standout contributions was his involvement in the mobilisation of the JD Assister for T3200 Trencher, where he transitioned from initial engineering to overseeing night shifts during the 24-hour operation. In this role, he ensured all work aligned with drawings and calculations, supervised lifting operations, and managed teams of welders, culminating in the opportunity to lead shifts independently.
“The planning and execution of the mobilisation and demobilisation were highly efficient. Harlyn’s team is professional, knowledgeable, and approachable, making collaboration straightforward. Both jobs were completed safely and methodically, with a strong focus on risk management. For each phase several complex lifts were successfully executed, requiring multiple steps and precise coordination, all of which were handled with skill and attention to detail. Their adaptability and problem-solving approach ensured the process ran smoothly. I’d be happy to work with them again in the future.” – Daniel Fraser – Enshore Subsea Project Manager
