Heavy-lift jack-up vessel Innovation, one of DEME’s DP2 installation vessels, left Damen Verolme Rotterdam shipyard in early September 2019 following a major refit. Innovation spent several months in the Verolme shipyard undergoing renewal of its aft leg sections and an overhaul of its jacking motors.
Innovation measures 147.5 metres in length and operates on an electrical rack & pinion jacking system. The vessel supports offshore construction via the installation of foundations, and has an unmatched track record in the offshore wind industry, having worked at wind farms across Europe.
The most significant aspect of this refit was the modification and re-installation of Innovation’s aft legs, each measuring 89 metres in length. Reinforcement work was carried out on the legs to enable them to cope with an increased rate of jacking operations, driven by the increased efficiency of the installation works.
Once the vessel was drydocked the two aft legs were removed and two new middle sections were inserted on the quayside, the refurbished leg finally being assembled from three parts. In total 47 metres of section per leg were replaced.
To overhaul the jacking motors, all 48 gearboxes of the aft legs were removed, overhauled in the shipyard’s workshop, and reinstalled on the vessel. Additional general maintenance work completed the refit, which included a box-cooler renewal, maintenance to the spudcan shoes, replacement of one aft thruster, small steel repairs and the installation of a new pile gripper.
Given the demanding scope of the vessel maintenance, project manager Rene van der Meulen was happy to have all works completed on schedule. “Project Innovation was a real challenge for our yard in all aspects,” said Rene. “Thanks to good cooperation with the customer, and the support of a hard working project team, we were able to redeliver the vessel to the customer on time.”
Damen Verolme Rotterdam was chosen as the location of this maintenance work thanks to the shipyard’s capacity and access to its facilities. Given the height of Innovation’s leg sections, Verolme shipyard’s mammoth drydock offered the possibility to lift the vessel’s legs with a crane installed inside the drydock while the vessel was sitting on the dock blocks, allowing maintenance to be carried out safely and efficiently. Following its extensive drydock period, Innovation has set sail to the SeaMade project in the Belgian North Sea to install 58 foundations.