After 9 months of diligent work by our engineering team, the concept design of our Jack-up Leg Cushion & Push-up (JLC) system has been completed. The concept design focuses on a wind turbine installation jack-up vessel (WTIV) with a displacement of 35,000 tons and a leg loading capacity of 15,000 tons. Based on hydrodynamic analysis of the leg landing process on a hard rocky seabed, the required cushion system capacity has been determined at 2000t x 0.6m, resulting in an improvement in leg landing sea-states from an average Hs of 1.2m to 2.4m.
The JLC system is installed at the bottom of jack-up legs. The structure is designed capable to resist the maximum loads on a conventional spudcan, and all vulnerable mechanical and electrical components are enclosed in a watertight compartment with access for maintenance. In case of malfunction of any primary elements, the JLC system can revert to its “closed” state without affecting other vessel operations.
Last week on February 25th, we received the Design Verification Report from DNV, confirming the compliance with DNV-OS-104 (Structural Design of Self-elevation Units). Our attention is now turning to validating the sand prevention system and conducting a HAZID for the leg handling operations with a WTIV operator.
The concept validation of our JLC system was funded by UNIIQ, an investment fund supported by the Netherlands Enterprise Agency (RVO) and South Holland Province. Further collaboration with Deltares, renowned knowledge institute in water and subsurface, is under discussion. We are seeking industrial partners and investors to support this development, which is aiming to increase the efficiency of offshore wind installation.