The nacelle cover is a protective structure that encloses the internal equipment and electrical components of wind turbines, enabling them to operate effectively in harsh weather conditions while safeguarding both internal systems and personnel from external environmental factors such as wind, snow, rain, salt spray, and ultraviolet radiation. Given the prolonged exposure of the nacelle cover and hub cover to natural elements and external conditions, they must meet stringent requirements for strength and rigidity, along with weather resistance, corrosion resistance, thermal stability, aging resistance, fatigue resistance, and UV radiation protection. Considering the overall load-bearing capacity of the wind turbine, the nacelle cover must be lightweight yet highly durable with substantial load-bearing capacity. Currently, composite materials such as fiberglass and resin are predominantly used for nacelle covers, though a small proportion are fabricated from metal.
The nacelle cover, serving as the wind turbine's outer shell, is manufactured from composite materials using advanced techniques including roll coating, lightweight RTM (Rapid Injection Molding), and vacuum casting. The process employs imported U.S. adhesive-coating sprayers and resin roll coating machines to ensure precise material ratios and uniform coating. The main structure incorporates a PVC foam core for enhanced structural strength, while the inner layer features sound-absorbing sponge to minimize turbine noise.
The most commonly used vacuum bag process in engine nacelle cover production involves the following steps: First, a resin coating is applied to the mold surface. Then, glass fiber, release cloth, and flow guide cloth are layered sequentially, with inlet and outlet spiral tubes installed. The vacuum bag film is cut to slightly larger dimensions than the mold and placed over it. Under negative pressure, the resin gradually penetrates the fibers until fully impregnated, followed by curing and demolding.
