CONVENTIONAL PVC EXTRUSION

A customised solution for any challenge

The Planetary Roller Extruder offers various features that are decisive for successfully producing and compounding PVC using conventional extrusion techniques. It is a flexible system featuring diverse processing possibilities that can gently process PVC, offers efficient self-cleaning and high-performance degassing, and can directly process edge trim film.

• Material-friendly processing of PVC using a Planetary Roller Extruder

  When processed in the Planetary Roller Extruder, PVC dry blends are continuously rolled out in thin layers while the temperature of the melt is precisely controlled – making this a very material-friendly process. This also avoids the formation of hot spots, resulting in homogeneous product quality.

• Efficient self-cleaning

  Unique: As a result of the 45° helical-toothed machine components (central spindle, planetary spindles, roller cylinders), the melt is continuously rolled out and conveyed in the extrusion direction in the Planetary Roller Extruder. The Planetary Roller Extruder is also self-cleaning to a large extent. The PVC in the Planetary Roller Extruder is continuously in motion as it is extruded. The powerful self-cleaning effect ensures that there are no ‘dead zones’ in which stationary PVC can suffer thermal degradation and cracking. PVC burners are not required. It is also possible to use different formulations (e.g. colour formulations) one after the other on a single machine configuration with fast changeover times while keeping scrap to a minimum.

• A flexible system

  Both rigid PVC and soft PVC formulations can be processed using the Planetary Roller Extruder. If necessary, it is possible to mix in other additives such as fillers, colourants, and reworked/recycled materials (recyclates) in the form of granulates, flakes or edge trim.

• Wide range of processing possibilities

  Impressive: Thanks to their modularity and tremendous adaptability in structure and configuration, the Planetary Roller Extruder can process all manner of PVC formulations. The conditions required for PVC processing (melt temperature, melt pressure, specific mechanical shear input, dispersion, etc.) can be controlled flexibly.

• Edge trim film can be processed directly

  Edge trim film can be fed directly into the Planetary Roller Extruder through a side feeder with vacuum suction. Suitable side feeder screw conveyors are chosen to cut the film into smaller, easily extruded pieces as it is sucked up and fed into the Planetary Roller Extruder. Here, the material is re-melted and fed back into the compounding process. The biggest advantage of processing edge strips in film form is that the material does not have to be granulated beforehand. As a result, it does not have to be subjected to mechanical or thermal stress yet again, resulting in significantly higher product quality.

• Outstanding degassing

  When processing PVC it is sometimes necessary to remove the entrained air, volatile components or aromatic compounds from the melt by degassing. Thin-rolling ensures ongoing replacement of the melt surface and the continuous generation of a large phase-boundary interface. The undesired compounds can then be removed from the process zone of the Planetary Roller Extruder by simultaneously applying a vacuum. Depending on the specific application, this can be done with a specially adapted side feeder fitted to Planetary Roller Extruder or with a feed screw flange-mounted to the Planetary Roller Extruder downstream using a vacuum dome. The melt can also be granulated directly or run through a profile die.