It is used for cleaning and classification of semolina in flour and semolina factories. The product, whose flow rate can be adjusted, is evenly distributed over the entire sieve surface by means of a curtain. The elimination process is carried out with 2 or 3 layers of telora. Equal vacuum is created on all sieve surfaces with the aerodynamic air duct and air adjustment flaps. Products with extended holding surfaces such as bran and bran are suspended under vacuum and separated from the product and pushed to the outlet duct. The bran-free product (semolina) is sorted by sieves