The most importat factor is airlock function on rotary valve . The reason for the simple construction on star shape dischaging feeder is that there exist big clearance inside the star shape discharging feeder. While airlock rotary valve can adjust the clearance to very small figure,for example ,the clearance can be adjusted to be 0.01mm. Moreover, inorder to meet the conveying effection , the rotary valve also add the accelerating chamber and accelerating chamber,which make the rotary valve working capacity is more reliable And reach a better sealing when increase the sealing type of shaft air seal between the reinforcement baffle and top cover.
To sum up,it is not qualified to use the star shape discharging feeder as rotary valves. For one thing, the star shape discharing feeder has cheaper price and simple structure as well as widely application in life. If the working require the airlock function ,you’d better to choose airlock rotary valve .The following table is regular technical data on airlock rotary valve :