This is the starting point for understanding how cone crushers work – and how they can make your mine or quarry more productive.

Inside your cone crusher

The basic principle is straightforward: the material to be crushed (the feed), drops into the crushing chamber. The mantle is a moving part that gyrates in an eccentric motion. That is, it doesn’t remain completely centred – it swings slightly as it rotates, continually altering the gap between the mantle and the concave (the ring outside the mantle that stays fixed in place.) As the mantle moves, it crushes the material against the concave at the points where the gap is smallest (the stones in the feed are also compressed against each other – that’s known as interparticle crushing).

The open side and the closed

As the feed is crushed, it falls and exits the crusher through the space at the bottom. The eccentric gyration of the mantle means that at any moment this space is narrowest at one point, and widest at the opposite point. The widest distance is known as the open side setting (OSS) and the narrowest, the closed side setting (CSS). These settings are important. The OSS is the largest distance between the concave and the mantle at the bottom of the crusher, so it determines the largest particle size of the outgoing product. As the smallest distance between the concave and the mantle, the CSS is the final crushing zone, and is vital for determining the product size, as well as energy consumption and crusher capacity.

a quick spin

are you aware of how fast the mantle in your cone crusher spins? it can make between four and seven revolutions fer second, so crushing material is compressed multiple times as it descends through the crusher.