The largest single ICE PVE vibratory hammer of Dieseko Group successfully dismantled wind farm Lely in the Netherlands. The Nuon Lely offshore wind farm was built in 1992 at 5 meter water depth. In December 2014 one of the wind farm’s turbines lost its rotor head and blades due to metal fatigue. At that time, it was decided that after 24 years of service the wind farm was approaching the end of its operating life and becoming less profitable. It was time to dismantle the wind turbines. 

The dismantling of the wind turbines started in October 2016. The PVE 500M was used to extract the foundation of the wind turbines. Two 1600 power packs worked in tandem to produce the 3072HP needed to circulate 3200 liters of hydraulic flow at 350 bar pressure to power the hammer. Four foundation piles, each with a length of 26m and a diameter of 3.20 to 3.70m， were removed one by one from the seabed and carried off via pontoons. The soil conditions were sand followed by clay layers. The enormous centrifugal force of the 500NF vibratory hammer allowed the piles to be extracted in only 45 minutes each. The hammer was built with a 3380kN extraction head, allowing the hammer a static line pull of 338t. The PVE 500M, which is a combination of two 250 kgm gear boxes patented GIANT system, has proven once again to have the power to extract 70 to 80 ton piles without any problems. 

During this project the Dieseko Group R&D department carried out several underwater sound tests. The main goal is to gain more insights in sound effects. Contact us for a full copy of the sound measurement results!  

What is the ICE tandem concept?

It is just like adding another slice of meet to a hamburger. We add another gear box to the hammer to double the eccentric force of the hammer. This type of tandem hammer is much easier to operate, and quicker to assemble and disassemble than the traditional way of connecting the gear boxes of two separate hammers side to side. It allows our users great flexibility in the set-up of their equipment.