Hollow profile of axial flow fan, fan diameter φ 800-4700mm. Mainly used in air cooler, cooling tower, central air conditioning, power transformer, wind tunnel, and diesel generator sets in various fields. The fan has the advantages of high efficiency, low noise, light weight, corrosion prevention and good advantage. The aluminum blade adopts advanced GW high lift airfoil, large camber wing section, hollow structure, aluminum alloy material, forming process of hot extrusion production, high strength, good rigidity, high manufacturing precision, smooth surface appearance