Offshore-coating – a robust protective jacket against the rough climate offshore
Unprotected steel corrodes in the air, in water and in moist soil. Corrosion damage can be prevented by protecting steel structures from harmful influences with a coat of paint or varnish. Offshore facilities are subject to much greater stress than onshore wind turbines. They have special corrosion protection needs.
Challenges in the offshore area
In the era of the energy revolution, offshore wind turbines have an enormous potential for power generation. The rough conditions on the open sea, however, pose great challenges to manufacturers and operators. Strong winds, high waves and salt water can cause damage to the large steel structures of the wind turbines very quickly. The water exchange area that may be under water or dry depending on the tides poses a special challenge. The solution can be found in suitable corrosion protection systems that can handle even the most demanding conditions.
Longer service lives with offshore coating
In contrast to most onshore wind turbines, which can easily be reached, offshore wind farms are usually not very accessible. Repair work on sea can be a hundred times more expensive than repairs on land would be. Replacing parts on site is nearly impossible. Therefore, coating systems for offshore use must be designed to resist the demanding climate conditions for the entire service life of 20 to 25 years.
While onshore wind turbines are usually found in areas of the corrosiveness category C3 (urban and industrial atmospheres, moderate coastal climate), offshore wind farms are usually in corrosiveness category C5-M (coastal and offshore areas with high salt loads) or corrosiveness category IM 2 (harbour areas with steel structures, piers, floodgates, offshore facilities). In these corrosion zones, unprotected steel parts will suffer material loss of up to 0.5 millimetres per year. High-quality coating can reduce this effect to 0.1 millimetres.
Selection of a suitable coating solution particularly demands on the expected stress and planned duration of use. Usually, the passive corrosion protection measures are supported by active measures such as the provision of sacrificial anodes of more anodic metals. These may also slow down corrosion.
Prohibition of solvent-containing coating systems
The Bundesamt für Seeschifffahrt und Hydrographie (BSH) demands that constructors of offshore facilities prove that the finished structure is solvent-free. Therefore, materials that offer outstanding corrosion protection, but that contain environmentally harmful solvents, must not be used for offshore-coating.
Offshore coating – A matter for specialists only
Only coating systems of the highest quality can resist the extreme requirements on sea for an extended period. We have many years of experience and comprehensive know-how in coating of offshore wind turbine components, such as boat landings, platforms, nacelles, rotor hubs and many other parts. Contact us. We will provide detailed advice.