Pelletizing Systems for Glass Fiber Compounds
In the past, glass fiber compounds were usually produced by strand pelletizing. Recently, however, there has been a clear trend toward underwater pelleting. Wear resistance and optimized machine concepts have shown that high throughput rates and low wear costs are possible for glass fiber compounds from underwater pelletizing systems.
__Why process an abrasive product by underwater pelletizing?__
* Cutting the product in its molten state permits a good integration of the glass fiber within the pellet.
* Compared to traditional systems, the development of fine dust is very low.
* The start-up of a Gala pelletizing system is automatic and produces minimum waste.
* In the event of extrusion process fluctuations, there is no danger of broken strands and downtime.
* The production at higher process water temperatures reduces cooling energy requirements.
Because of the highly abrasive characteristics of these polymers, special wear resistant systems are available for these applications. The true challenge does not lie in the production of the pellets but in the downstream processing, and in particular the drying of the pellets.
Challenges to be met:
* Reduction of the number of parts in the product flow
* Wear resistance of the parts in contact with the product
* Quick replacement of worn parts
Design modifications, the selection of special materials suitable for abrasive wear and the simple replacement of parts in the product flow have resulted in a solution that has already been successfully implemented in several applications processing PP, PBT, PC, PA and other materials with glass fiber proportions up to 66%.