Small high-pressure centrifugal fans are widely used in the production of agricultural products and feed processing

Small high-pressure centrifugal fans are widely used in the production of agricultural products and feed processing. It is the air transportation of grain and. Grind materials, feed and tea important equipment, but also some agricultural fluidized drying equipment necessary. Common fluidized drying machines, requiring its work in optimal flow velocity (apparent wind), which requires changes in load or when dry materials that increase or decrease the amount of wind  Instrument valve manifolds . According to the working principle of the fan performance curve and the pipe resistance curve of intersection of the fan for the fan's operating point, thus changing the substance of the air volume is to change the fan operating point. Small wind turbines used to change the throttle and speed control are two ways to change the amount of wind. In order to reduce the fan shaft power,  Instrument manifolds  is placed in the fan inlet side of the tube, by varying the valve angle (ie, changing the opening) to achieve increased pipe resistance off a small butterfly, the characteristic curve of the pipe. Adjustment method, although the increase the butterfly losses, there is no economic side, but because the method is simple, reliable, easy to operate, the scope of the requirements in the regulation on small wind turbines are still too large widely used.