Projekty

Offshore Kołnierze

An important part of the J-tube construction of offshore wind foundations.

At the end of each J-tube is a cone, called a bellmouth, which guides the electro-cable from the seabed into the J-tube.

J-tubes are the support and protection of cables between the seabed and the upper part of the offshore wind foundation. J-tubes provide the necessary protection for the cables and are an essential part of any offshore wind foundation structure. The product consists of steel tubes bent into the required J- or S-shape to form the full length of a J-tube. At the end of each J-tube is a bellmouth that guides the installation of the electro-cable into the J-tube.

The production of bellmouths

A bellmouth consists of several cones of different diameters. The gradient from small to large diameter is worked out by our engineers into efficiently manufactured parts. Through a smart layout of the sheet material, several parts can be extracted from a sheet. This limits material loss. Cutting is done on one of our plasma cutting machines. During the process, the cut-outs are immediately provided with welded edges.

The cut-outs are rolled, welded on the longitudinal seam and re-rolled. Any excess length is removed using robot technology. The various conical sections are then welded together on the circumferential seam.  For a complete J-tube construction that is ready to be built in, we weld a guiding ring to the end of the bellmouth and the bellmouth is mounted on the J-tube. 

Kersten has a strong track record in supplying J-tubes with bellmouths. We have successfully delivered J-tube structures for several offshore wind projects in the North Sea, Baltic Sea, Irish Sea, Atlantic Ocean.

Download Offshore Wind track record