Flexible fallpipe vessel

Van Oord was at the cradle of the development of flexible fallpipe vessels and have been market leader in subsea rock installation in the North Sea region for almost 30 years. Since then market opportunities grew, as did the scale of our operations. Want to read the whole story of a tale of a triumph? Read all about it in our magazine.

In many places on the ocean floor, even at great depths, there are cables, pipelines and subsea templates that must be stabilised and protected. Van Oord holds the world record for the precise placement of rock in water depths of 1300m and beyond.

Van Oord has three advanced flexible fallpipe vessels in its fleet. Nordnes, Stornes and the latest addition is Bravenes, a unique piece of equipment. The vessel, with a deadweight of 14,000 tonnes, a length of 154 metres, and a beam of 28 metres, is suitable for installing a wide range of rock sizes.

Bravenes is equipped to perform three different types of rock installation, namely the fallpipe through the moon pool, a fallpipe over the side, or a tremie pipe over the side. This third ship configuration allows the vessel to install rock very close to offshore platforms, such as monopiles. Bravenes brings a new level of innovation to subsea rock installation.

Van Oord Offshore has developed a technique for dredging at great water depths. This Deep Excavation System (DES) is an innovative method to prepare a sea bottom profile for installing offshore pipelines. The DES allows dredging to take place at depths varying from 100 to at least 1,000 metres. Van Oord’s flexible fall pipe vessel Stornes can be equipped with this in-house developed system. It consists of the combined application of a sophisticated grab and a Fall Pipe Remotely Operated Vehicle (FPROV). The DES has a very accurate position control system and generates only very limited turbidity, which is vital in view of potential nearby sensitive marine environment like coral.