Size Reduction Equipment
Common industries that utilize size reduction on a number of these materials include industrial manufacturing, in order to reduce large materials to desired sizes for processing; mining, in order to reduce the size of large quarried and mined materials; road and bridge construction, in order to reduce the size of rubble and building materials; automotive, for the reduction of junked vehicles for easier disposal; and agricultural, to reduce grain and other produce that are used in the mixing of other food products. Additional industries that benefit from the use of size reduction equipment include printing, wastewater, power generation, pharmaceutical and metallurgy. Different types of size reduction equipment work best on varying levels of material hardness and abrasiveness, although most can be used on wet or dry materials.
There are four main ways that the various types of size reduction equipment are able to reduce the size of materials: crushing, impaction, cutting and grinding. The act of crushing takes place when force that is amplified as a result of mechanical means is transferred through a material that is stronger than the material being crushed. Crushers hold materials between two solid surfaces and then bring the two surfaces together with enough force to either deform or break apart the materials. Impaction refers to the effect of force that has been transmitted as the result of a collision or the clash of two surfaces. Impactors, also known as impact crushers, come in two main categories: vertical shaft impactors (VSI) and horizontal shaft impactors (HSI). Cutting, probably the most familiar process, is the act of separating one solid part into multiple, small parts. Cutters such as shredders, slitters, knife cutters and dicers are not commonly used in industrial applications, but they are often seen in commercial and consumer products applications where they offer the advantage of giving the broken off parts a definitive shape and size. Lastly, grinding is the reduction of size by friction, enabled through the rubbing together of two hard surfaces. In grinding mills, grinding media are often utilized, which are tiny round balls of hard, abrasive materials used to chip away at the materials being reduced.
