Cable cutting

Subsea Innovation has completed the design, supply and live demonstration of a cable and cable protection system (CPS) cutting tool that can rapidly and reliably remove a CPS without the need for divers. Activity in the installation of CPS is currently high and is forecast to remain so and this tool gives the ability to remove a CPS in the minimum time. This is particularly key for the future as offshore windfarm projects are being installed in increasingly deeper waters where diving becomes more dangerous and costly.

There were numerous offshore wind industry leaders in attendance, including sales partner Tekmar Energy Limited, DONG Energy, VBMS, Jan de Nul, and CWIND. The event was held at The Underwater Centre near Fort William in Scotland and involved a full scale demonstration of the installation and removal of a CPS from mock-up offshore foundations.

Cable protection systems are designed to be maintenance free for the full service life of the wind farm. However, for decommissioning purposes and in order to reduce risk within the industry it is important that any equipment that is installed subsea has a proven and robust method of removal.

The Underwater Centre provided a work-class remotely operated vehicle (WCROV), which was launched from an offshore vessel and carried out the operations in Loch Linnhe, which is a seawater lake.

The demonstrations were carried out over a two-day period. On the first day the removal operation was performed on a mock-up J-tubeless monopile foundation, whereas the second day was reserved to carry out the same operation on a mock-up J-tube. Both demonstrations were considered successful with operations being completed considerably quicker than expected.