Crushers for Sale (23)

Understanding Crusher Types – Primary, Secondary & Tertiary

Crushers are categorised depending on the size of the material you are staring out with and the size you want to finish at. If you are staring off with pieces around a metre, then chances are, the best you will get from one machine run is down to about 30cm – that’s your primary crusher. To reduce the size further aim for a secondary machine that can reduce this size by a third again. If you are looking to achieve a really fine crush – let’s say for sand – then you’ll need a fine tertiary crusher.

You can now invest in a stationary hybrid machine that will act as a primary, secondary or tertiary machine

Stationary Vs Mobile Crushers

For large quarry operations with high outputs, a static machine makes sense when you can bring the materials easily to the crusher. For added flexibility a tracked crusher means that the machine can follow the path of the work and has its own engine power.

Wheels or tracks?

A wheeled crusher on the other hand is a well-engineered semi-trailer brought to site by a relatively standard truck and assembled in place using the trailer chassis as the backbone of the crusher. These are useful for short term, smaller deployments.

Impact Vs. Cone Vs. Jaw Vs. Gyratory Crushers

Jaw Crushers

If you are looking for a crusher to carry out that all-important initial crush, then chances are you’ll be looking for a jaw crusher. These are fairly basic pieces of kit and relatively straightforward to operate. – Check the teeth type as there are differences such as wide, sharp, corrugated, heavy duty. Take advice on the correct teeth for your application. The typical range of sizes for a mobile jaw crusher would be from about 30 tonnes right p to 135 tonnes. The larger the machine, the greater the maximum feed size and the higher the throughput capacity, again from about 225 to 1,000 metric tonnes er hour (mtph). Stationary machines will tend to have larger feed sizes and capacities compared to their weight (as they do not need to power themselves around).

Cone Crushers

Once the material is at the right size, the aggregates can be secondary, or tertiary crushed using a cone crusher. These work best with a maximum material starting size of about 20cm, although the sizes can vary. It is possible to adjust the settings. On a typical machine, several different crushing chambers will be available as standard. The crusher can easily be matched to changes in production by selecting the right crushing chamber and eccentric throw.

Impact Crushers

Impact crushers can be set up to handle any type of crushing application, although are best suited to primary and secondary operation. The machines use ‘beaters’ or ‘hammers’ (hence they are also known as hammer crushers) and crushed further on a series of plates which send them back to the hammers. An impact crusher can have a horizontal shaft (HSI) or a vertical axis (VSI). The VSI machines will typically have a much smaller feed size than the HIS variant but will screen to a lot finer levels. The HSI machines can effectively do the work of a primary and secondary crusher in one, thanks to their high reduction ratios.

Gyratory Crushers

These are the real high output machines. Available only as static crushers, these machines run to 500 tonnes with feed openings over 1.5 metres wide.