In the aggregates industry, there are three main types of crushers: jaw, cone, and impact. Each of these specialized pieces of equipment can produce quality aggregates at high tonnages. So, how do you choose between them? The key is to know the strengths and weaknesses of each crusher. This way, you can choose the right product to match your specific needs. For example, if you’re a contractor looking for a mobile crushing solution, an impact crusher mounted on a portable plant is ideal. Before we dive into why this is, let’s look at some differences between these three types of crushing units.
The Three Main Types Of Crushers
Jaw crushers, like the Grizzly-King Jaw Crusher, are powerful primary crushers. They’re used in mining, pit and quarry, construction aggregates, and demolition recycling. They have a high output rate: up to 950 tons per hour. Jaw crushers use compression between a fixed and swing jaw in an eccentric motion to force material through the crushing chamber.
One of the disadvantages of the jaw crusher is that the aggregate it produces has a flat, slabby particle shape. For most construction applications, a rounder shape is more ideal as it has better compaction properties for road construction and binds better with cement to form strong concrete material. Since the output material is oddly shaped, jaw crushers are typically used as a primary crusher, followed by a secondary crushing system, like a cone crusher.
Cone crushers, like Sepro’s Blackhawk 100 Cone Crusher, are used as a secondary and/or tertiary crusher. Cone crushers also use compression to crush particles as feed is squeezed between an internal liner and a rotating cone. The final aggregate product is well shaped and consistently sized for a wide variety of uses.
For fixed crushing plants that will be in operation for decades, the jaw/cone crusher combination is often a good choice. These machines have a high capital cost, but are extremely durable and reliable.
Impact crushers are quite different than cone and jaw crushers in that they use collision forces to crush the feed. Here’s how it works: fast-rotating blow bars smash input material against stationary impact curtains. This style of crushing produces a round or cubic final product.
Benefits Of An Impact Crusher
Impact crushers offer cost savings and versatility that cannot be matched by other crushing systems. Since jaw crushers and cone crushers are often used together, capital costs are high. An impact crusher can be used as both a primary and secondary crusher.
Portable plant operations that use cone and jaw crushers require up to three different trailers. Each crusher requires its own chassis, then an additional one is required for a portable screen. An impact crusher portable plant can house both the crusher and screen on a single trailer.
Disadvantages Of An Impact Crusher
Since impact crushers use powerful collision forces to break apart particles, they have higher operational costs due to higher wear rates when compared to cone and jaw crushers. They can also be less efficient as more fine material is created during the crushing process compared to jaw and cone crushers.
A Primary And Secondary Crusher In One
Using a screen and an impact crusher, you can create a two-stage crushing circuit. First, you run the feed through the crusher to create a coarse aggregate. Then you run the same feed through the circuit a second time for your final product. Although the capacity is reduced when the crusher performs double duty, the capital savings here are substantial since one machine is doing the job of two separate crushers.
Impact Crushers Are Versatile
Fixed operations dealing with a single type of aggregate will generally use a jaw crusher/cone crusher combination. However, if you’re a contractor who needs versatile equipment, impact crushers are the ideal choice.
Impact crushers can work in a quarry one month, a concrete recycling plant the next, and then on a site where asphalt needs to be crushed after that. You can optimize your efficiency by mounting an impact crusher to a portable plant for a completely mobile crushing solution. These portable plants have a small footprint as a screen can be mounted on the same chassis as the crusher.
Creating portable plants for jaw and cone crushers is possible. However, a separate chassis is needed for each crusher and a third is necessary for a portable screen.
If you’re still having trouble deciding on the best crushing system for your circuit, contact the experts at Sepro Aggregates. Our decades of experience building portable plants and developing aggregate solutions can help you achieve your goals, whatever they may be.