This series of fans has the characteristics of high efficiency, low noise, stable pressure curve, and wide range of use. It is mainly used for indoor ventilation, air exchange, cooling, and dust removal in factories, mines, sports venues, opera houses, basements, hotels, restaurants, shopping malls, and large buildings. It can also be used in conjunction with other types of mechanical equipment for gas circulation. The medium being transported is air and other non flammable, harmless, and non corrosive gases to the human body;B4-72Using explosion-proof motors, it can be used for ventilation and air exchange of flammable and volatile gases, with gas temperature ≤80℃, no viscous substances, dust or solid impurities are allowed in the gas ≤150mg/m3。