In recent years, my country has increasingly focused on the development and utilization of new green and clean energy sources. Wind power, as a new type of green and clean energy, has seen significant development. Its abundant energy reserves and huge market potential have effectively alleviated the energy shortage. With the construction of more and more wind power plants and the increasing installed capacity of wind power, maintenance issues have become increasingly prominent.
Wind turbine towers are a crucial component of wind power systems, providing support and pressure relief to ensure reliable system operation. However, due to the harsh environment in which wind turbine towers operate, they are susceptible to corrosion and damage, which weakens their protective function. This not only reduces power generation efficiency but also increases operating costs, hindering the sustainable development of wind power. Effective anti-corrosion measures can improve the corrosion resistance of wind turbine towers and extend their service life, thereby reducing operating costs and ensuring they better serve the wind power system.
Common causes of rust include: old coatings exceeding their service life, resulting in powdering, peeling, blistering, and loosening; incomplete or absent surface preparation during initial application, leading to coating peeling, loosening, and penetration of contaminants and moisture into the substrate; uneven paint film thickness due to poor control during application, resulting in large areas of ineffective primer film and inadequate corrosion protection; premature coating failure due to a flawed anti-corrosion system design; damage caused by natural disasters (such as severe sandstorms); and damage during transportation and hoisting due to insufficient protection. While appropriate repair methods can be used for different causes, as the saying goes, "He who does not plan for the future will have trouble in the present," and proactive prevention is worse than reactive maintenance.
The first step in corrosion protection for wind turbine towers is to select qualified anti-corrosion coatings. Because the climates of the north and south differ, the required anti-corrosion technologies also vary. Therefore, when selecting anti-corrosion coatings, the influence of the natural environment should be fully considered. Coatings with excellent comprehensive performance, designed based on effective experimental data on corrosion conditions under different environments, should be chosen. Currently, most wind turbine towers in my country use polyurethane coatings that meet European and American standards. This type of coating technology is relatively mature; a film thickness of only 20 micrometers is sufficient to meet the 40-year corrosion protection requirement. Its annual film loss is low, requiring no maintenance or only one maintenance during the normal service life of the wind turbine, extending the effective service life of the protective coating layer, significantly improving the service life of the wind turbine tower, and reducing maintenance costs.
Secondly, it provides an ideal operating environment for corrosion protection. Due to the large size of wind turbine towers, various problems inevitably arise during the corrosion protection process. Appropriate rotating fixtures for wind turbine towers can be designed and manufactured according to actual conditions and applied to the corrosion protection operation. The two ends of the tower are connected to the fixture with bolts, preventing direct contact between the tower surface and the support points. This avoids secondary contamination during sandblasting and painting, preventing rework. Continuous rotation of the tower during spraying results in a more uniform coating, making it easier for workers to operate and establishing a stable spraying process, ensuring consistent spraying quality. Using this fixture provides an ideal operating environment for the corrosion protection of wind turbine towers, preventing the final product from failing to meet requirements due to environmental factors, shortening the corrosion protection process time, improving efficiency, and ensuring the quality of corrosion protection.
However, aside from human error during construction, natural disasters can still inevitably corrode the coating of wind turbine towers. Therefore, using appropriate anti-corrosion technologies and construction processes is still essential. The operating steps are as follows:
1. Surface treatment of local rusted areas: The oxidized rust layer and old coating are completely removed by spraying to expose the metal base material, reaching grade 2.5. The edges of the treated areas are ground with a power abrasive wheel to form a gradient transition layer so that there is a smooth and glossy surface after painting.
2. After spraying, the primer should be applied by hand according to the original matching plan to achieve the specified film thickness. The intermediate coat can be applied by brushing or spraying to achieve the original matching film thickness. If spraying is used, the edge areas need to be protected and masked. The masking shape should be "口" to form a regular appearance effect.
3. Topcoat application: If a partial repair solution is adopted, after the intermediate coat has reached the required thickness and meets the requirements in point 3, the topcoat can be directly sprayed or brushed to achieve the original design thickness requirement.
4. Due to prolonged exposure to wind and sun outdoors, metal wind turbine towers are inevitably susceptible to corrosion. Therefore, effectively cleaning surface rust and enhancing corrosion resistance are crucial. The cleaning method involves using 80-100 grit sandpaper to abrade the surface, removing the powdery layer, grime, and dirt from the old coating. For areas with oil stains, chemical cleaning is used to remove the oil. After thoroughly cleaning the surface, the topcoat is applied.
