What is the difference between shredder and granulator

What is the difference between shredder and granulator? Shredder and granulator are the two basic size reduction machines. Overall speaking, they perform the same job, that is take a larger component and reduce it to smaller sized output. However, when you look in detail, shredder and granulator are much different, and it could be a costly mistake if you buy a shredder whilst what you actually need is a granulator, or visa-versa.

The primary difference between granulator and shredder is the output size they produce. Shredder is a single-stage device that breaks down scrap materials into more manageable pieces with size ranging from 20 to 100mm, especially for dual shaft shredder which has no screen at the outlet, there could be a wide variation in particle size and shape. Whilst granulator can repeatedly reduce the size of the scrap until it passes through the screen holes which are 6 to 12mm diameter, it is the ideal machine to produce consistently uniform granules. So the best way to know if you need a granulator or a shredder is to determine how small size you want your output particles to be.

Another major factor that distinguishes shredder and granulator is feeding. Granulators operate at high speed (from 415 rpm to 1460 rpm) with relatively low torque. Shredders, on the other hand, operate at lower speed (3.6 rpm to 83 rpm) with high torque. With such design features, it is not ideal to feed a lot of big sized and high density material at a time into granulator, because it create a lot of noise, lead to jam and can even potentially damage the granulator. Most granulators requires meter-fed by hand, conveyor, or some other feeding mechanism. Shredders are quite the opposite, the more and heavier the scraps are, the easier it is to shred as the weight of the scrap on top of the hopper can force the lower scrap down to the cutters. Moreover, most shredders can automatically reverse the rotor to clear jams that can occur from over feeding, particularly of thick material, or foreign matter like hard metal. So for shredders, feeding is strait forward, simply dump the material into the hopper and then the machine will get the job done by itself.

It is not always either or situation, sometimes these two types size reduction machines work together with each other in which the shredder perform coarse size-reduction task and then the shreds are further fed by conveyor into a granulator for final sizing to consistent, small and uniform granules. At Sinobaler Machinery, we manufacture various types and sizes of shredders and granulators, if you’re not sure of what your equipment needs are, contact us and we will assess your needs and provide you with the optimal size reduction solution.