Offshore bellmouths

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

Robust, solid and able to withstand extreme offshore influences