Materials that, due to their characteristics, must be used with a standard particle size are presented in the form of granules.

In polymers, polymer granules, color concentrate granules and additives are used for the manufacture of profiles or molded parts by injection or extrusion, rotomolding, etc.

The size of the granules depends on what you want to manufacture and also depends on the production process.

Blade granulators produce polymer granules by simply cutting the threads that have come out of the extruder and are at room temperature. These blade granulators can have a single blade that goes up and down or several blades placed on a rotating drum that allows a homogeneous cut.

The time and speed with which these drums rotate determines the final size of the polymer granule, however its diameter will depend on the tension applied to the thread with which its diameter is reduced.

The disadvantages of these granulators are the clogging that occurs regularly, the possibility of cutting hot material that is later rejoined by heat effects, and wear of the blade.

In economic terms, they are the cheapest option for granulating extruded polymer.

The granulators that produce the cut under water ensure that the still molten polymers fall into a colder medium, generally water, and solidify due to heat transport effects. By this technique, typically spherical-shaped granules are produced; while the granules made with a razor have a cylindrical shape.

Underwater granulators are much more efficient, producing granules of more homogeneous volume and controlled volume. The disadvantage of this type of granulators is the initial investment cost in the equipment.