Heerema Marine Contractors

Heerema Marine Contractors installed a Delft Offshore Turbine (DOT) monopile at the site of Eneco’s Princess Amalia offshore wind farm (Prinses Amaliawindpark) in the Netherlands. The work was reported on 1 June 2018 and related to the offshore installation of a single monopile foundation using Heerema’s heavy-lift vessel Aegir. The monopile was installed using a Vibro Lifting Tool operated from Aegir. The installation approach vibrated the pile into the soil and was described as combining a vibro-hammer and lifting tool, reducing the need for additional equipment typically used for pile handling, upending and driving to final penetration. The installation was carried out with Aegir operating in floating mode on dynamic positioning (DP), with the monopile free-hanging from the crane hook and without the use of a motion compensation frame. Verticality was monitored during pile driving, enabling control of pile inclination while operating in DP mode, and the article reported that the pile was installed within a 0.5 m target box with an inclination of 0.3 degrees.