SF Series

SF Series

Specially designed for PVC processing and recycling applications

The Rotary Technology has been used successfully in PVC processing and PVC recycling applications for more than 30 years. The SF Filtration System operates continuously and pressure and process constant. The screen change procedure does not influence the product quality. Furthermore, short flow channels – free from dead spots – guarantee an extremely short dwell time of the melt in the system.

The advantages of the SF Filtration System

  • Constant 
    By always keeping the size of the free active screen area constant, the pressure can be kept constant during the whole production process (max. pressure variations of ±1,5bar). Also, melt temperature and viscosity are permanently free from variations. Thus, the end product quality is always constant.
  • Quality
    Melt purity and quality downstream of the filtration system are permanently achieved. Rheologically optimized melt flow channels.
  • Streamlined
    Due to the optimal rheological flow channel design, the dwell time of all the melt in the filtration system is very short (< 1 minute). No danger of material burning in dead spots.
  • Straightforward
    The operator is informed in time about upcoming screen changes by the control system. Changing screens is a simple and quick procedure and does not have any influence on the process and product quality.
  • Compact size
    The compact design of the SF makes even in a very confined space a simple and cost-efficient integration possible. Thanks to the compact design and the high quality insulation, the energy consumption is extremely low.

Mode of operation

When a pressure increase upstream of the filter due to contamination is registered, the filter disk is indexed by means of a hydraulic drive. This guarantees that the free screen area is always kept constant and that the pressure variation in front of the filter is < 1.5 bar.

Fig. SF Mode of operation



The filter disk – on which the screen cavities are located in a ring pattern – rotates between the two filter blocks. To change the screens, the safety cover has to be opened. The production process is not disturbed by the screen change procedure. Thanks to the modular design of this filtration system, it is possible to replace the few wearing parts (such as heater elements and bearing bushings) during operation. Continuous production over many years is thus made possible.