Dry separators in the VARIO or PT series are optimally suited for the extraction of dust from spring grinding processes. The KLR filters are equipped with a PTFE membrane to achieve a residual dust content of < 0.1 %, and enable clean air recirculation of purified air into the workplace without additional secondary filters. This substantially contributes to increased energy efficiency. However, the TRGS 560 regulation regarding air recirculation must be followed. The continuous compressed air cleaning of the filters ensures continuous operational safety.