Traditionally, Heerema used steel plate welding and wedges for sea fastening these components on unmanned barges. However, synthetic or textile chains offered advantages over the previous method, which took 48 hours to be completed for welding and inspection release by surveyor. In contrast, synthetic chains only needed 1.5 hour of lashing time for 3 nacelles with 12 chains each, directly followed by inspection and release.
This productivity improvement became possible due to the avoidance of time-consuming welding, the use of existing lashing points, the lightweight of synthetic chains, and their easy surveyance. Next to this, their improved ergonomics make them safer and easier for workers to handle, while also preventing dents and scratches on the wind turbine components.
For Heerema, the key was to find a solution that would maximize speed and efficiency. The Heerema team had previously incorporated Dyneema®, the world’s strongest fiber™, in their mooring ropes and lifting slings. Additionally, in 2020, a team member involved in the Arcadis Ost 1 project successfully utilized synthetic chains on a project in Taiwan. This track record convinced them to use DoNova® PowerLash chains with Dyneema®, manufactured by Dolezych, for the Arcadis Ost 1 project.
The chains consist of multiple layers of Dyneema® fiber webbing and their unique construction makes them significantly lighter and more flexible than steel chains. As a result, heavy objects such as wind turbine nacelles can be safely and easily secured to the barge deck without the need for a large crew.
Similarly, the superior flexibility of DoNova® PowerLash chains with Dyneema® makes them easier to manoeuvre in tight spaces – another key requirement when working in confined offshore environments.