For flour sifting, there is a great dispersion of standards and procedures, which makes it practically impossible to determine a globally accepted standard. Even so, and based on our knowledge of the market, we suggest four possible alternatives. It should be noted that the results obtained will not be comparable between them. The objective is that the proposed sieves serve as a basis for unifying criteria in the customer-supplier field, suggesting that both parties use the same criteria.
Based on standardized sieves in openings and tolerances:
2.Proposed criteria for sieves.
The dimensions of the sieves should be 200mm.Ø or 203mm.Ø (8″).
Choose the same diameter of the sieves, otherwise they could not be adjusted to each other.
The height of the sieves can be either 25mm or 50mm.
The construction material is stainless steel, both for the frame and for the mesh or sheet.
Based on standardized sieves in openings and tolerances.
Based on the ISO 15793 standard concerning the determination of the semolina fraction.
Observation: The characteristics of the sieves used under this standard may not meet all the requirements of ISO 3310.1, especially with regard to the wire diameter of the meshes. It may happen that sieves with the same nominal opening, but made of different wire diameters, do not give comparable results in the sieving process.
With 5 sieves a wide granulometric spectrum is covered. The sieves are made of wire mesh with a large useful surface.
It is formed by those sieves with synthetic meshes, either in polyamide or polyester, specially designed for the sifting of flour and semolina. In this case, there is a wide range of openings to choose from.