The DWT-I type FRP axial flow roof fan is widely used in medium and low pressure and large flow use places. Such as industrial and mining enterprises, workshops, warehouses, gymnasiums, theaters, power plants, laboratory, rubber factories, auto factories, motorcycle factories, textile and metallurgy places, etc. This series of fans is characterized by beautiful appearance, compact structure, high strength, light weight, corrosion resistance, anti-aging, low power consumption, low noise, reliable operation, economical and practical, convenient installation and maintenance. The gas is not allowed to contain viscous substances, dust and hard particles is less than or equal to 150mg/m3, the gas temperature are less than 60, the relative humidity is less than 99%.