Model SF series axial-flow ventilator has smooth streamline surface with exceptionally good rigidity, firm paddle-wheel structure, even and flat screen cover, elegant and pleasing outline and tones .Model SF series fan is divided into pi0pe-line type, wall type, post type four kinds according to the use requirements. It is separated into 12 machine numbers according to the paddle-wheel diameter. This series product is widely applicable for the wall type exhaust, post blast, pipeline ventilation in the mining and industrial enterprises, civil purpose buildings. It can also be used in the working occasions of chemical, light industry, food, medicine, medicine, metallurgy, power station, communications etc and the storage ventilation air-conditioner system.