Blyth Offshore Wind Farm

Off the northern coast of England, Strukton, BAM Infraconsult and BAM Nuttal are currently constructing a huge wind farm. Eekels Pompen supplied and installed various temporary pumps for the purpose of seating the foundations for the turbines. This was the first time a floating, submersible, concrete caisson was used for this type of application.

Concrete caissons

The caisson method is commonly used when building offshore wind farms. This method involves floating containers, which are pumped full of water to force them to sink. These caissons are concrete structures that are guided into position on the bed of the North Sea. This approach makes it possible to build offshore wind farms in areas where the sea is very deep. The caissons developed by BAM Infraconsult are turbine foundation structures consisting of a conical concrete base with a diameter of 30 metres. The lower part of the wind turbine mast, measuring roughly 60 metres, is attached to the foundation first at the production location. The entire structure is then sunk to a depth of 40 metres by pumping ballast water into the caisson.
The foundations are filled with seawater to make them sink. To carry out this process as efficiently as possible, Eekels Pompen supplied the following temporary pump system. A PP200 diesel-powered high-pressure pump to fill the concrete caissons with seawater and force them below the surface. This PP200 was fed a supply of water by two submerged Hidrostal F10K-HD units. A pair of B11-350-GG pumps transported the sand and sea water mixture to the caissons. The overflow water from the caissons was pumped away by 10 Grindex type Major N units. Eekels delivered all the different pumps and was also responsible for all the pipework.

Peace of mind

Eekels had the task of keeping everything running 24 hours a day. Obviously getting the equipment to the location and installing it on the pontoons in good time was extremely challenging. In addition, Eekels assigned a team to the pontoons for a period of three months to prevent faults and/or other problems. As a result, our organisation successfully provided a total solution for this project.