Screening Machines

Zeppelin separators are ideal for processing bulk material, reliably removing foreign material and verifying grain sizes with pinpoint accuracy.

Everything under control

Quality control of finished bulk material, whether in the food industry or in the plastics industry, is increasingly in focus, so it is no surprise to learn that the food industry already conducts extremely stringent inspections on incoming raw materials, to find and remove even the tiniest foreign bodies, such as pieces of nutshell, small stones in grain, and even tiny fragments of plastic. Quality control requirements for bulk material have also been considerably tightened in other industries, such as the carbon black industry plastics industry.

The ideal system for preparing bulk material is a rotary sifter from Zeppelin Systems. It can be used for preliminary sifting before silos, after-screening below filling stations and containers, or as an inline sifter for pressure-tight use with up to 0.8 bars of overpressure or vacuum in pneumatic conveying lines.

The rotary sifter has been successfully used in the food industry for decades; so it is guaranteed that all parts that come into contact with the product are designed to maintain food quality, are based on the EHEDG guidelines and health and safety regulations, and are correspondingly easy to clean. The design of the sifter drum also means that it can be easily inspected, cleaned, and if necessary replaced, via the inspection openings on the side of the sifter. The drum may be made from polyester or VA stainless steel. A slotted sifter drum is recommended for use in heavy-duty applications. Additional rings seal off the sifter drum from the product chamber.

The sifter is used in the plastics and carbon black industry in a very similar way as in the food industry: For the removal of foreign bodies and verification of grain size. The mesh size of the sifter drum can be customized from 0.25 mm to 8 mm. The main benefit of this is in the continuous checking of raw material – in other words, the separation of coarse material and the loosening or breaking up of product lumps for better use of raw materials. In addition, the sifter helps protect any sensitive processing machines downstream of this step.

In general, rotary sifters are compact, robust, and low-vibration, and are specifically designed to ensure outstanding efficiency and a long service life, as can be seen in features including the double bearings on both the conveying screw and beating bars. The sifter can be fitted with automatic sifter drum monitoring (Screen-D-Tect) as an option. This continuously monitors the condition of the special screening mesh during operation. Any screening material tear or sifter drum wear is detected and alerted, minimizing the risk of a production breakdown or defective batches. A facility to automatically clean out the sifter drum is also possible. The rotary sifter is of course also designed for use in zone 21 or 22, in compliance with the ATEX Directive 94/9/EC.