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Crusher

technology Maturity 11-13 Next article →

A crusher is a specialized machine designed to reduce large rocks into smaller fragments. These fragments can take the form of gravel, sand, or even fine rock dust.

Dodge type jaw crusher
Dodge type jaw crusher

Beyond simple size reduction, crushers are essential for changing the form of waste materials. This makes it easier to recycle or dispose of them properly. In mining, crushers help separate different parts of a solid mix of raw materials. By reducing the size of ore, workers can better identify pieces with different chemical compositions.

Ruffner Red Ore Mine gyratory crusher, North of I-20 at Madrid Exit, Birmingham (Jefferson County, Alabama)
Ruffner Red Ore Mine gyratory crusher, North of I-20 at Madrid Exit, Birmingham (Jefferson County, Alabama)

To understand how a crusher works, we must look at the science of materials. Crushing is the process of transferring a force through a material. This force is amplified by mechanical advantage. The machine holds the material between two solid surfaces that are either parallel or tangent.

Scheme Jaw Crusher
Scheme Jaw Crusher

When these surfaces move together, they generate enough energy within the material to cause a change. This happens in two main ways: fracturing or deformation. Fracturing occurs when the molecules of the material separate from one another. Deformation happens when the molecules change their alignment in relation to each other.

Scheme vsi crusher
Scheme vsi crusher

Industrial operations use several different stages of crushing to reach a specific size. These are categorized by how much they fragment the starting material. Primary crushers handle the largest, coarsest materials. Secondary crushers take that output and break it down further. Tertiary and quaternary crushers are used to reduce ore particles into much finer gradations. Different machines use specific methods to achieve these results. These methods include impact, compression, attrition, and cutting. If the material needs to be even smaller, the crushing stages are followed by milling stages.

History shows that crushing began with very simple tools. The earliest crushers were hand-held stones used against a stone anvil. These tools used the weight of the stone to boost muscle power. People also used devices known as querns and mortars. For most of industrial history, crushing was done by muscle power. Miners used the concentrated force of a pick or a sledgehammer. During the Renaissance and early Industrial Revolution, water-powered trip hammers were used in smithies. It was not until explosives became common in the mid-nineteenth century that mining changed significantly. This led to much larger chunks of rock that required massive machines to break down.

Key figures in the history of power helped drive these mechanical changes. In 1712, Thomas Newcomen invented the atmospheric engine. This was the first practical device to use steam to produce mechanical work. These engines were used across Britain and Europe to pump water out of mines. Later, James Watt created an improved version of this engine. In the 1700s, Abraham Darby moved his business to Coalbrookdale to utilize coal and water power. By 1822, Darby's ability to melt pig iron allowed for the casting of large iron cylinders. This reduced the cost of cylinders by nine-tenths compared to expensive brass versions.

Today, crushers come in many shapes and sizes to suit different needs. Some are massive, stationary units used in heavy mining.

Portable Plant - Metso Nordberg HP300 Close Circuit Plant
Portable Plant - Metso Nordberg HP300 Close Circuit Plant

Others are mobile units that can crush rocks as large as 1.5 meters. These mobile units can work directly at a mine face to increase production. There are also small, portable crushers weighing between 6,000 and 60,000 pounds. These are often jaw crushers that can travel from one jobsite to another. Some even attach to heavy machinery, such as the crusher buckets used in quarries.

Crusher bucket quarry
Crusher bucket quarry

Crushers are vital components of larger industrial and infrastructure systems. In a typical mine, a processing line might start with a crusher, followed by a SAG mill, and then a ball mill. These mills act as grinders to reach the finest particle sizes. In road construction, crushed rocks are combined with asphalt or concrete. This creates the durable surfaces used for modern roads. From the massive coal breakers that fueled growth in the 1600s to modern mobile plants, crushers remain essential for managing the earth's raw materials.

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🖼️ Images & Media (9)
File:Newcomen atmospheric engine animation.gif
Newcomen atmospheric engine animation.gif
File:Portable Plant - Metso Nordberg HP300 Close Circuit Plant.jpg
Portable Plant - Metso Nordberg HP300...
File:Scheme Jaw Crusher.gif
Scheme Jaw Crusher.gif
File:Dodge type jaw crusher.jpg
Dodge type jaw crusher.jpg
File:Ruffner Red Ore Mine gyratory crusher, North of I-20 at Madrid Exit, Birmingham (Jefferson County, Alabama).jpg
Ruffner Red Ore Mine gyratory crusher,...
File:Scheme vsi crusher.jpg
Scheme vsi crusher.jpg
File:T80 7.jpg
T80 7.jpg
File:Crusher bucket quarry.jpg
Crusher bucket quarry.jpg
File:Crushing jaws movement in a Xcentric Crusher bucket.png
Crushing jaws movement in a Xcentric...
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