Shredder, grinder, or granulator, how to choose? (2)

GRINDING

Grinding, most simplistically stated, is the shaving, chipping or “grinding” of small pieces off of a larger piece.  Or in the case of size reduction, grinding off small pieces until the original part is in thousands of smaller consistent chips, usually less than 1/4” to 1/2”. 

1. Grinding large rejected parts back to smaller chips that can then be recycled into making more parts.

2. Reducing larger raw materials to chips that can be mixed with other compounds to make new components.

3. Reducing organic materials for bio-fuels production.

4. Grinding carpet and other textiles for fiber reclamation.

Essentially, grinding is an application used to take any larger raw or rejected material and process it in the grinder to obtain a small enough particle, chip or fiber suitable for the manufacturing of other components parts.  The best example being to grind a raw or rejected piece of rubber or plastic so it can be used to make things like bottles, tires, or those neat storage bins we all have in the garage. 

GRANULATING

Granulators are perhaps the most commonly confused machines with grinders, as they essentially do the same thing; they take larger components and make them smaller. Perhaps the best way to know if you need a granulator is to determine how small you want your discharged component to be.  Granulators have the ability to reduce certain materials to a much smaller particle size than a grinder. The reason for this is that a granulator differs in design significantly from a grinder in the following ways:

1. Most all granulators have an “open rotor” design.  This means that there is a great deal of air space around the rotor for product agitation and cooling.  The open rotor allows for better processing of lighter materials that would not be well suited for a closed rotor design.

2. Many Grinders on the other hand, especially the type of grinders offered by Jordan Reduction Solutions, have closed rotor designs.  Meaning the rotor is closed, high speed and very tight tolerances.  These type rotors leave little room for the product being process to go anywhere other than across the cutting edges.

There are advantages to both designs mentioned above, but simply put; each design is more applicable to specific products.

1. A granulator, with an open rotor type design, is normally more applicable in taking small components in the ½” to 6” or 8” sizes and reducing them to much smaller chips than a grinder would be used to do.  Often in the range of producing 5/16” flake to even powders.

2. Granulators are often used as an after process for materials that have been size reduced previously.

3. Granulators are well suited for lighter materials such as plastic bottles which do not grind well in a closed rotor design unit.