Granulator Sound, Service & Safety
Apart from the fundamental components of a granulator, there are other aspects of the design that will have important ramifications on the usability of a specific model. Tearing up materials is by nature a noisy process, and the effectiveness of the sound enclosure will matter to the working environment near the granulator. Perhaps more important is how easy and safe a granulator is to service.
Not surprisingly, most of the sound generated by a granulating process occurs in the cutting chamber. But significant noise can be generated by the drivetrain as well. A full sound enclosure is designed for maximum noise suppression and will typically lower the sound decibel level outside the machine by 10 to 30%.
Poor service on a granulator can result in poor quality granulate with excessive dust and fines. So accessibility to the cutting chamber,rotors and knives is extremely important. Knives must be kept sharp and clean for best results, and the cutting gap between rotating and stationary knives should be easy to set and maintain. Ease of cleaning is also important particularly in short-run environments where the granulator must be thoroughly cleaned before moving on to the next material.
Safety during servicing is important. Features such as rotor lock, safety interlocks to access the chamber, hopper & chamber lift assist, tipping prevention and so on are desirable in any granulator installation. Cumberland uses a variety of interlocks to assure service work can be done safely including:
- Zero Rotor Speed Detection – Prevents users from accessing the cutting chamber until the rotor has stopped.
- Hopper Lock – Automatically engages with manual disengage.
- Rotor Lock – Automatically engages with manual override.
- Chamber Lock – Upper chamber is locked via solenoid-activated interlock.
- Discharge Bin is locked via solenoid-activated network.
Overall the granulators design meets ISO-12100 category 3 requirements which requires two sets of redundant interlock contacts, safety rated components and short circuit protection.