Shredder Rotors

There are two basic types of rotor configurations: single-shaft and multi-shaft. Rotors drive material into the cutting zone either between the rotating and mating stationary knives (single-shaft), similar to a granulator or between another mating rotor’s cutter disks (multi-shaft). Multi-shaft shredders come in either 2-shaft or 4-shaft versions. Like most elements of size reduction equipment, choosing the right rotor configuration depends on the size, weight, and density of the scrap being shredded.

Single-Shaft Shredders

Single-shaft shredders are best suited for larger, solid mass products such as tough materials, large parts, rolls of film and other difficult materials. Similar to a granulator, material is driven into the cutting zone by rotating cutters on the rotor through mating stationary knives mounted on the bed of the shredder.

Single-shaft shredders are best suited for larger, solid mass products such as tough materials, large parts, rolls of film and other difficult materials. Similar to a granulator, material is driven into the cutting zone by rotating cutters on the rotor through mating stationary knives mounted on the bed of the shredder.

Single-shaft shredders also commonly include a ram-feed assist to help drive material into the cutting zone and classification screens to better control the size of the shredded material output. A key advantage to these shedders is that they are less inclined than multi-shaft designs to recirculate partially shredded material which, when shredding different materials, can encapsulate some of the materials into one another.

Typical applications:

• Baled film
• Large purgings
• Carpet bales
• Bowling balls
• Baled bottles

2-Shaft Shredders

Multiple-shaft shredders are used as a “pre-cutter” to break materials from their original form into more manageable, steady feed forms. They are best suited for non-solid mass parts and scrap. With 2-shaft shredders material is driven between rotating cutter disks mounted on each rotor shaft to tear the material. Cleaning fingers are positioned in the gaps between the cutter disks on each rotor to strip shredded materials from the shaft. Many shredders utilize keys for disassembly and reassembly of cutters and disks for sharpening. Some have an optional classification screen to control the size of the shredded material output.

Typical Applications:

• Tires
• Extruded sheet (not stacked)
• Gas Tanks
• Baled Film
• 55-gallon drums

4-Shaft Shredders

With 4-shaft shredders another set of rotors and cutting disks are added to the cutting chamber. Effectively tripling the number of cutting zones, they are designed to shred heavy duty materials at high volume. Operating at lower speed but higher torque, 4-shaft shredders are good for applications where small to medium particle size is desired.

Typical Applications:

• Polyethylene banding
• plastic film
• PET bottles
• Electronic scrap
• Tires
• Contaminated materials