ROC the classifier
for very fine material

The finest ROC’s in life are not always diamonds

Classify sharper, grind finer, produce high-performance minerals with superior quality. After 90 years of classifying innovation, we developed the ideal fine and ultra-fine classifiers. Meet ROC and U-ROC.

product purity
d98 = 5 - 100 microns
greater performance
up to 9000 rpm
fast return on investment

roc - designed for finer products

Our clients demand higher material purity, top cuts of d98=5-100µm, greater performance, low energy consumption, and affordability. With all of that in mind we developed the fine classifier ROC. ROC is not only a reflection of our vast experience but is the answer and go to solution for fine mineral classification.

Technical details

  • gravimetric or pneumatic feeding, from above or below
  • easy and fast maintenance due to direct drive
  • Specially designed fine material discharge to the top with low pressure drop
  • Oil lubricated bearings allow heat dissipation
  • A sealing air seal ensures a sharp upper grain boundary and thus high product quality
  • The sealing air is generated by an external fan

With roc we achieve superfine results.

Kurt Bernegger, Managing Director
Bernegger GmbH, Austria

What is the function of a separator?

The separator classifies the material stream into two partial streams depending on the particle size. The separator is charged with powdered material, consisting of particles of different sizes, in a continuous process. It defines the finer particles as the finish product by selecting them from the feed material. The rejected coarse particles and the non-selected fine particles are fed out of the separator as a second mass flow.

What is the function of the jalousy ring in classifiers with a rotating basket?

The jalousy ring serves as a static pre-classification device to define the amount of material passing to the rotating cage. At the same time, it limits the space around the rotating cage which makes it easier to adjust the flow conditions.

What does the term "loading factors" mean?

We often talk about two loading factors with regards to the separator. The feed loading and the fines loading in [kg/m³]. It means the mass of the respective fraction per air volume.

The higher the permissible loading factors, the smaller the separator can be designed to classify the required tonnages. Permissible loading factors mean the lowest value under which a separator can still effectively and reliably fulfill its function. Coarse material loading is not relevant in this context because it has no influence on the functionality of the separator.

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A story of efficiency

Efficiency in grinding is our heritage and our future.
Since 1925.

Making grinding processes as efficient as possible is a science in itself – one to which we dedicate our entire expertise and spirit of innovation. From the invention of the first MONOBLOC diaphragm to the technical fine-tuning of the separator QDK. How we became what we are today.