Reducing the size of large materials is important for many different applications, but mostly for construction and mining applications. In the past, crushing abrasive materials was very difficult because worker were using hand-made tools or no tools at all. Today, there is a whole range of choices when it comes to crushing materials, each one providing a safe, efficient and dependable operation. Operators can maximize their productivity by choosing a piece of crushing equipment that is especially designed for particular type of material and application. The size reduction can be done by using few crushing methods: impact, attrition, compression and shear crushing. In fact, these are the four basic ways/machines for crushing materials.
Impact Crushers – The impact crushers are the most common crushing equipment that is used in the mining industry. Impact refers to a collision of one moving object against another (fixed one), which pretty much sums up the working principle of the impact crushers. The material that needs to be crushed enters the crusher from the opening at the top. Then, a moving impact plate crushes the material until the size meets the operator’s requirements. The impact crushers have a high reduction ratio of 20:1, so they are even suitable for crushing grain size materials.
Attrition Crushers (Cone Crushers) – These crushers reduce the size of large materials by scrubbing them between two hard surfaces. The attrition crushers, or usually called cone crushers, are ideal for crushing medium-hard and abrasive materials. Featuring two hard surfaces, they can compress any material and reduce its size as much as needed. The attrition crushers can be used for both primary and secondary crushing, but are more efficient when used as secondary crushers. The main advantages of this crushing equipment are low investment and running costs and great versatility.
Compression Crushers (Roll And Jaw Crushers) –The compression crushing method is the oldest and most efficient. A basic compression crusher comes with two surfaces to press materials in between and crush them to pieces. Although these crushers are used for small reduction ratios, they can certainly deal with some abrasive materials that are not sticky. The roll crusher and jaw crusher are the most common compression crushers. These versatile pieces of crushing equipment are suitable for a wide range of crushing applications.
Shear Crushers – While the previous crushers compress and apply impact on various materials to reduce their size, the shear crushers trim or cleave them. However, the shear crushers go together with other crushing machines, most commonly with impact or compression crushers. These crushers are capable to crush all types of materials, but most efficient for coarse products.