Subsea Foundation & Floater Corrosion Mapping

Marine and shallow water environments offer particularly corrosive conditions to wind turbine steel foundations or floaters. This is naturally a major source of concern to wind farm operators as structural steel corrosion may lead to the catastrophic collapse and sinking of the whole turbine. Subsea foundations and floaters need to be inspected on a regular basis.

This is often a complex job as subsea foundations and floaters are covered by thick and hard marine growths. Deploying a diver or ROV to perform a visual inspection is not enough. Marine growth needs to be removed to visually inspect the actual conditions of the underlying steel surface and measure its remaining wall thickness.

We have designed for that purpose two main types of subsea wall thickness (WT) measurement tools, equipped with different sensing technologies:

WT Screening Tool:

Our range of WT Screening Tools are equipped with advanced electromagnetic sensors able to assess and map the remaining WT of the structure through thick coating and solid marine growth (up to 150mm thick). It allows for a fast and cost-competitive screening of remaining WT with the huge advantage of not requiring any surface cleaning.

WT High Definition (HD) Tool:

Our range of WT HD Tools are equipped with pulse-echo and phased array UT sensors able to deliver detailed corrosion map of remaining WT with an accuracy of +/- 0.2mm.

All our tools can be deployed by diver or by ROV in their standard configuration. They can also be deployed from the platform using a remotely operated crawling robot.

Our WT Screening Tools and HD Tools are complementary tools often used in combination with each other: our WT Screening Tools are typically Used first used to scan large areas of subsea structures through marine growth and identify critical locations of major WT losses. Our WT HD Tools may be deployed in a second phase at these critical locations for mapping exactly any defect once marine growths have been locally removed.