The axial-flow fans of SF series is blessed with smooth streamline surface, stable operation, high effiency, low noise and less energy consumption and so on, and classed into the following four models according to use requirements:manifold pipeline type, stationary type, wall type and position type, as 12 models is accoring to impeller diameter. The series of poucts are widely used in the mining industry abd civil construction for the wall exhaust, post blast, pipe ventilation, and also used for the air conditoning system in warehouses and working places in departments such as chemicial industry, light industry, food,medicine, metalluargy, power plants, transportion and so on.