Sifter for increased reliability and end product quality

Inspecting finished products, whether in the food or plastics industries, is gaining in importance. It is therefore not surprising that, in the food industry, raw materials are meticulously inspected at reception to ensure they do not contain impurities such as pieces of nutshell, small stones in grain or plastic pieces. Requirements for quality control of products has since considerably increased as well in other sectors such as in the carbon black and plastics industries.

The ideal component for this bulk material process is Zeppelin Systems’ rotary sifter. The rotary sifter is used as a preliminary sieve in front of silos, as a final sieve underneath containers or as an inline sifter for pressure-tight operation up to 0.8 bar excess and vacuum pressure in pneumatic conveying systems. The rotary sifter has been successfully used in the food industry for decades. For this reason, all parts coming into contact with the product have been designed in food grade material according to EHEDG guidelines and BG rules and are easy to clean, partly thanks to the sifter drum design. The drum can be easily inspected through the lateral inspection opening of the rotary sifter, cleaned and replaced if necessary. It is available in polyester or stainless steel. If robustness is needed, the wedge wire drum sifter is a particularly sturdy alternative. Additional sealing rings seal the sifter drum from the product chamber.

In the plastics and carbon black industries, the sifter assumes very similar tasks as those in the food industry: to remove foreign matter and verify the particle size. The mesh size of the sifter drum can be customized and ranges from 0.25 to 8 mm. The advantages are mostly seen in the continuous raw material control, i.e. the separation of coarse materials and the loosening and dissolution of product lumps for an improved utilization of the raw material. Furthermore, the sifter protects all sensitive downstream processing machines.

The rotary sifter features a compact and low vibration construction particularly designed for long-lasting superior performance. That is why, for example, the feeding screw and beater bars are equipped with double bearings. As an option, the sifter can be equipped with an automatic sifter drum monitoring (Screen-D-Tect) which continuously monitors the state of the special screen fabrics during operation. Any damage to the sifter or wear to the sifter drum will be detected and signalized. This reduces the risk of production downtimes and reject batches to a minimum. Automatic dedusting of the sifter drum is included as well. The rotary sifter is also naturally available in a design accorting to ATEX directive 94/9/EC for operation in zone 21 and 22.