While the maize flour that does not meet crushing standard will be screened out from Double Bin Sieve and then delivered by Suction Fan 3 into Flour Mill 3 for further grinding. The discharged material is delivered by Suction Fan 3 into Double Bin Sieve 2 for sieving: the corn flour that meets standard will be ejected by Fan 4 ; those substandard will be delivered by Fan 3 into .