Can the melt pump deliver high filler melts?
The answer is: yes. The melt pump is used for melts with high filler content, which is extremely demanding on the performance of the melt pump. It is very abrasive for high filler content melts and also increases or decreases viscosity, which in turn increases or decreases drive unit pressure and power consumption. Coatings must be added to protect tool steel from wear and corrosion. For example, the Enhanced Melt Pump has a special PVD coating that can handle CaCO3 filler content up to 83%. Compounds containing large amounts of glass fibers (≤40%), carbon black CB, TiO2 and WPC (wood-plastic composites) can also be processed.
Are there any materials that are not suitable for processing with a melt pump? For example, PLA is extremely corrosive, and PVC is thermally sensitive. But both materials can be processed using a melt pump. Generally speaking, if you plan to process corrosive, heat-sensitive or easily degradable materials, you need to specify and communicate with the melt gear pump manufacturer, and the manufacturer will carry out special treatment of the pump to meet the production needs. Besides thermoplastic materials, melt gear pumps are also commonly used in rubber (NBR, SBR) and TPE, SEBS and SBS.