How does an Impact Crusher work?
Ideal for recycling, primary and secondary crushing applications.
Impact crushers reduce mineral materials such as concrete, asphalt and natural rock in size to produce a valuable commodity product. A fast spinning rotor throws the material against a solid stationary impact wall. The striking and impacting causes the material to shatter into smaller pieces. The result is a very homogenous and cubical product leaving the crusher box.
Good for processing reinforced concrete, asphalt, cinder blocks, sand & gravel, soft rock, and hard rock.
Ideal for producing a spec product without the need of a primary jaw crusher.
Material produced by an impact crusher is easier to grade and compact making it perfect for base and subbase.
There are 2 main types impact crushers - horizontal shaft impact (HSI) crushers and vertical shaft impact (VSI) crushers.
The horizontal shaft impactors are the most common impactor type that can be used in recycling, primary and secondary crushing applications. This type impactor will take reasonable size pieces and produce small output material.
Vertical shaft impactors are designed to process already small material even smaller and are therefore used in a tertiary crushing application (e.g. producing manufactured sand).
The crusher box includes a rotor with hammers (also called blow bars). Depending on the rotor style you will have either 3 bars or 4 bars. Hammers are cast iron replaceable wear parts that are actually in contact with the material. They are designed to withstand the many impacts of the material. The impact wall (also called apron) has several crushing stages and is armoured by thick wear plates.
Once the hammer hits the big material entering the crusher box it is thrown against the wall and starts ricocheting between hammers, wall and other material particles. As soon as the material is small enough the fit in between the rotor and the lowest crushing stage of the impact wall it will leave the crusher box at the bottom.
The beauty of impact crushers is their versatility in terms of input material and output size. There are many different designs out there but generally speaking impact crushers can produce material from 3" down. The smaller the input material the harder it gets to crush. The output gradation can be adjusted through various settings.
The higher the speed the more fines are produced.
Altering the distance between the rotor and the impact wall influences gradation and overall output size.
Common hammer setups are 2 high 2 low or 4 high hammers.
On most crushers this works hydraulically. The aprons need to be adjusted when you want to produce a different output material or when you need to readjust your crusher settings to accomodate the wear progress.
RUBBLE MASTER impact crushers use a simple design to change the crusher setup easily, quickly and safely within minutes. The unique proprietary crushing chamber design allows operators with limited impact crushing experience to operate our machine efficiently from day one.
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