New-design cutter hubs and blades for Nordson BKG’s underwater pelletizers are said increase throughput, improve transportation of pellets from the cutting area, simplify cutter assembly, and provide new options for reducing wear to die plates and blades. The components were on display last month at NPE2015.
In underwater pelletizing, the cutter hub and blade assembly produces pellets from polymer as it exits the holes in the die by rotating rapidly against the die face, with blades mounted at angles to the face of either 45 degrees or 90 degrees. The new design increases throughput by accommodating up to 100% more angled blades per hub (36 instead of 18) or 54% more straight blades (40 instead of 26). As an alternative to increased throughput, the operator can reduce pelletizer RPM, maintaining standard throughput while reducing wear to die plate and blades.
Nordson carried out the redesign using the same metal as in the standard hubs and blades but employing a casting process rather than machining the metal
The redesign also makes it possible for the first time to use the same hub for accommodating either angled or straight blades, providing new versatility for users who run multiple materials.
Nordson says the new-design hub and blades can be used on any Nordson BKG underwater pelletizer with throughputs from 2200 lb/hr to 77,000 lb/hr.