In this article we will discuss the process of choosing a shredder. The aim is to facilitate the process of deciding which shredder is the most suitable for our requirements.

Before we move on, I'll look at the following questions:

  • What will be the size of the input raw material?
  • What material is the input raw material made of?
  • How much raw material do I want to shred and how fast (kg / hour)?
  • What is the required output? Size of the shredded material?

We now have the basic information necessary to make our decision. Shredders are divided into "pre-shredders" and "shredders".


This is slow-running shredding. They can process heavy, hard and large blocks of input raw material. The size of the input raw material ranges from 600mm x 1000mm x (height - "unlimited"). These dimensions are derived from our pre-shredders. With such a pre-shredder it is possible to shred, for example: Thick-walled sinters, plastic "cakes", jerrycans, thick-walled pipes, large-scale mouldings, pallets..... For some technological processes, the output fraction is not small enough and therefore it is necessary to grind the raw material in knife mills.

If the input raw material is a large block, it is advisable to equip the pre-shredder with a sliding hopper. Its great benefit is that it can "cut" material from large blocks of input material.

If it is necessary to shred large pieces with a small volume such as: tanks, fenders, bumpers, large spools, pallets, etc., we recommend equipping the pre-shredder with an upper pressure. This significantly increases the shredding speed.

Most such pre-shredders have a controlled drive. First of all, this ensures engine protection. And secondly, it contributes to increasing the efficiency of shredding. Voltage, current and cos phi are measured on the engine. Based on this, the engine load can be evaluated and the hopper feed mode is automatically selected according to the set shredding characteristics. The characteristics can be adjusted on the control panel.


Knife shredders - high speed

They are suitable for thin-walled and less demanding raw materials. The input material determines the type and size of the shredder. The shredders can have knives perpendicular to each other or inclined to each other. The advantage of knife shredders is high aggressive geometry of the rotor, which provides a large space in front of the rotary knife. This feature results in the material not bouncing off the rotor and being pulled into the cut.

If the shredder has knives perpendicular to each other, it is easier to manufacture the machine, but the shredding operation itself is dynamically demanding. The inclined knives ensure smooth shredding operation, better energy balance, less heating of the material and formation of less dust particles, higher shredding efficiency.

In many cases, the shape and size of the input hopper are addressed depending on the dimensions of the input raw material. The size of the shredded raw material is regulated in most shredders by the size of the screen holes. The size and location of the screen determines the shredding performance.

  • The size of the screen hole must take into account:
  • Size of the shredded material
  • Type of the shredded material
  • The size of required shredded material.

The distance between the rotary knives and the screen depending on the crushed material is a parameter that significantly affects the crushing performance.

It is advantageous to use extraction in the knife shredders, which ensures a homogeneous size of the crushed material, increases the shredding performance, removes the proportion of dust particles. It should be noted that the correct extraction design is affected by:

  • Type of shredded material.
  • Quantity of transported material
  • Size and type of transport pipes, transport length.
  • Cyclone size and shape


The correct choice of shredder depends on several parameters. At the same time, we must also take into account the minimum price costs for the implementation of the entire system, using high-quality components that guarantee long-term use.

For shredding lines, it is important to optimize the shredding performance of the pre-shredder and the shredder so that the entire system operates at optimal load with minimum energy consumption and maximum shredding efficiency.

Based on 25 years of experience in the design and manufacture of shredding machines and lines, we will be happy to help you design the optimum system.

You can find the offer of our shredders here or contact us

Why PROFING Piešťany spol. Ltd.

  • We don't just sell machines, we solve the problem.
  • PROFING shredders have been used for decades in various operations, always with excellent results, which prove their.
  • The shredders have been tested and tried for years.
  • Thanks to the demand of our customers with specific requirements and a group of experienced engineers with many years of experience, our shredders are constantly improving. We are gaining experience from the diversity of shredding.
  • We immediately transform results from practice into new shredders, thanks to small-batch production.
  • We have manufactured almost a thousand shredders and shredding lines that are used throughout Europe.

PROFING shredders are characterised by:

  • Inclined position of rotary and fixed knives (scissor effect). Better efficiency.
  • High robustness of the shredding system. Longer service life.
  • Using high quality materials. Low wear.
  • Quick cleaning of the machine. Easy maintenance.
  • Quick knife changing.

The set of these parameters ranks these machines among the world leaders in their category. Thanks to our portfolio of machines we have become suppliers, of small companies as well as large automotive concerns across the European market and to a lesser extent, we have also exported our machines outside the EU.

Whether you decide to make an order from PROFING Pieštany or another company, we wish you much success.