Introduction to Three Types of High Efficient Crushers

A roll crusher crushes using compression, with two rolls rotating about a shaft, towards the gap between the rolls. The gap between the rolls is set to the size of product desired, with the realization that the largest feed particle can only be 4 times the gap dimension. The particles are drawn into the gap between the rolls by their rotating motion and a friction angle formed between the rolls and the particle, called the nip angle.

Some major advantages of roll crushers are that they give a very fine product size distribution and they produce very little dust or fines. Coal is probably the largest user of roll crushers, currently, though. Usually, these crushers will have teeth or raised forms on the face of the roll.

Impact crushers use impact rather than pressure to crush materials. The material is contained within a cage, with openings of the desired size on the bottom, end, or side to allow pulverized material to escape. This type of crusher is usually used with soft material such as coal, seeds, or soft metallic ores.

A cone crusher is similar in operation to a gyratory crusher, with less steepness in the crushing chamber and more of a parallel zone between crushing zones. The essential difference is in the short spindle, which is not suspended, but instead supported, in a curved universal bearing located below the gyratory head or 'cone'.

As rock enters the top of the cone crusher, it becomes wedged and squeezed between the mantle and the bowl liner or concave. Large pieces of ore are broken once, and then fall to a lower position where they are broken again. This process continues until the pieces are small enough to fall through the narrow opening at the bottom of the crusher.