Marine Growth Removal from Floater Hulls & Subsea Structures

Marine Growth (or “micro-biofouling”, including barnacles, mollusks, algae…) is an ever-present issue on offshore wind turbine floaters and subsea structures. Its presence causes an increase in the tubular diameter and projected area of these structures, leading to increased hydrodynamic loading. It also makes difficult any visual inspection by divers or ROV, and may hide severe corrosion of the underlying structural steel plates.

Being able to perform periodic inspection of floaters and subsea structures is critical as offshore wind turbines are exposed to major fatigue and cycling stresses which may lead to the collapse of a turbine should its floaters or structures be affected by severe corrosion.

Marine growth removal is a complex technical matter as it can be very hard, thick and adherent. Using mechanical techniques (scrapping/brushing) to remove it is poorly efficient and extremely time-consuming, making this option unrealistic for such large, submerged structures. Mechanical techniques also tend to remove the underlying primer and anti-fouling paint coats, exposing the structure to accelerated corrosion rates.

Building on our experience in the oil & gas where platforms are affected by similar issues, we develop innovative marine growth removal solutions based on low and high pressure water-jetting techniques which preserve the integrity of the underlying paint coats. Our tools can be deployed by diver and ROV on a standard basis, or can be adapted for deployment from the turbine platform using cable systems or remotely controlled crawling robots.

Our marine growth removal solutions can be combined with our corrosion mapping tools to provide an integrated “all-in-one” inspection service.