When extruding plastic products, production waste with vastly different material properties and shapes is generated (e.g. semi-finished plastic products, profiles, pipes, sheets, purges and small trimmings). The yield, shape and properties of the products to be comminuted dictate the configuration of the best-suited feed and comminution processes.
The achievable end-product size varies dependent on the desired end application. Whereas with many applications, 4 – 8 mm suffice (ideally dust-free), fineness values in the powder range can also be required.
It is important – especially when the feed product is often changed – that the system can be cleaned quickly and easily.
Machine feeding must generally be monitored constantly, because an uncontrolled material feed constitutes a frequent source of interference in the production sequence. If too much product is fed to the system, it can stall and come to a standstill in the worst case, and if too little product is fed, this will take its toll on the economic efficiency.
Granulation, Dedusting and Fine Grinding of extruded plastic parts
Hosokawa Alpine systems are designed to function reliably and to be cost-efficient due to smart solutions. The classic solution is the combination of a granulator from the Rotoplex or Compact Line with a downstream dedusting step.
The latest innovative development available for the comminution of extruded articles sets new standards with regard to easy cleaning, low space requirements and uncomplicated material feed. We are talking here about a totally new shredder-granulator which combines the self-dosing properties of a shredder with the product fineness values of a granulator. The processing of feed material lengths of up to 6 metres or start-up chunks of up to more than 100 kg is possible without any problems. The machine concept permits easy access to the grinding chamber to enable fast and thorough cleaning.
If end-product fineness values of less than 5 mm are required, every system concept can be combined with a fine cutting mill. Fineness values of 99.5% < 500 µm can be reliably achieved by means of fractional screening and an optional water-cooling system – even with temperature-sensitive products.
Explosion-protection concepts for filters and equipment are available.
Advantages of Shredder-Granulator combination:
- Simple feed of the material from containers; dosing is automatic
- Hinged door guarantees easy access to the grinding chamber for maintenance and cleaning
- Minimised space requirement
- Reduced power requirement
- Fully automated process control
- Explosion-protection concept for filters and equipment