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Toner Classifiers TTSD

The feed material is dispersed by the classifying wheel and transported through the same by the classifying air. The dust entrained in the air is transported through the support wheel and discharged via the fines discharge. The coarse product is rejected by the classifying wheel and conveyed to the coarse material discharge. The product routing is designed such that no back-mixing can occur and a high quality of dust removal is ensured. The special configuration with the support wheel is patented; it permits optimum access for quick and thorough cleaning at minimum downtime.

Protected by additional patents, the TTSD tandem toner classifier is a refinement of the TSD toner classifier, primarily with the aim of improving the precision of cut even further by means of two consecutive classifying stages. At the same product loading of the classifying air, the tandem toner classifier achieves a much higher precision of cut than the TSD, or at a constant coarse product quality, achieves a higher loading factor. This makes it possible to almost treble the throughput in comparison with the TSD.

The TTSD toner classifiers were developed especially for dedusting toner. The demands made of the end-product quality in toner processing are so high that particle counters (Coulter Counter) are employed for the quality control. Specification of the dedusted coarse material is given in number%, whereby the specification generally permits 3-10 number% < 5 µm. The focus of attention during development was a maximum precision of cut, although other aspects such as handling and safety as well as operating and installation cost were also taken into account.

One- or two-stage ultrafine classifier with a high precision of cut for optimum coarse products.
Specially designed for classifying toner and pigments, e.g. minimisation of the ultrafine portion <2 - 5 µm.
Hinge-back housing makes the machine easy to clean when changing the product.
Classifying wheel(s) arranged vertically
Because of the dust explosion hazard associated with processing toner, the classifiers are designed to be explosion-pressure-shock-proof to 10 bar overpressure. Every machine is available with a type test certificate as defined in the ATEX Directive 94/9/EC. Tandem toner classifiers hinge open hydraulically. Different toner classifier designs are available to suit different customer requirements:

Stainless steel
Polished, Ra 0.8 µm
Three-fraction classification for special toner applications. To this end, the classifier is equipped with a special classifying wheel in the 2nd stage, and the classifying system is laid out for the collection of the 3 fractions toner powder, dust and coarse particles.

PUHLER Grinding systens



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