There are many kinds and styles of crushing gear available on the market. Tricon Mining Equipment explains how to choose the best crusher for your operational needs.
If you are a rock, sand, gravel or mineral processing industry veteran, you recognize that there are numerous different types and styles of crushing equipment. The exact crushers you need—jaw, cone, impact or gyratory—depend on the job-site, the product you’re making, and how many tonnes you want to produce.
An individual crusher’s construction and capabilities also dictate where in your processing operations it will fit. That is, you might also have more than one type of crushers located in primary, secondary and tertiary stations in a circuit format to operate the necessary material reduction work. Each type of crusher brings unique strengths and advantages to the process.
This article focuses on compression-style jaw crushers, which are most often employed in the primary stage of a crushing circuit. It’s essential to understand that cone crushers are sometimes used in their place, and we’ll also discuss a little bit about when cone crushers may also be favored over jaw crushers.
What is a Jaw Crusher?
Jaw crushers are sometimes also referred to as “rock breakers,” which speaks to their brute force. They are nearly exclusively used as primary crushers due to the fact that they excel at breaking up some of the biggest and hardest materials into more manageable pieces for further reduction by way of different crushing equipment. Jaw crushers have a multitude of advantages, including:
- Ability to handle many different types of materials—from hard granite to reclaimed asphalt pavement (RAP) and more—without showing as much wear and tear as primary impact-style crushers.
- Typically output minimal fine materials and dust.
- More environment friendly than primary gyratory crushers.
Due to their smaller physical size, jaw crushers are also best for tight spaces, such as underground mining and mobile crushing applications, where some other primary crushing options do not fit.
What are the Different Types of Jaw Crushers?
Jaw crushers have been around for almost 200 years and are one of the most “historic” crusher types. Because of this, jaw crushers have gone through many technological advances through the years to become more durable and to enhance their movement to minimize choking and increase operational speed. These design tweaks over time have perfected a machine that’s simple enough in its working principle that it may never come to be obsolete.
Today, two main jaw crusher configurations can be seen from the major equipment manufacturers. They differ primarily based on how the swing jaw moves, although their output is similar.
Double Toggle—Blake Type or Overhead Pivot Movement
Double toggle movement jaw crushers like the Blake style (named for the inventor of the first successful mechanical jaw crusher, Eli Whitney Blake) have long been a popular choice for crushing hard and abrasive rocks, as well as sticky feeds. These jaw crushers have high energy-efficiency. The overhead pivot design further reduces wear and tear on crusher faces versus the Blake style.
Single Toggle—Overhead Eccentric Movement
More compact than double toggle designs, the single toggle movement jaw crusher was at one time unable to take delivery of such large feed sizes, although it can generally run faster. Technological improvements solved the feed size issue, and now these machines are famous for how rapidly they work. They do experience extra wear and tear than the double toggle style crushers, however wear parts are widely available and economical.
How Does a Jaw Crusher Work?
Different jaw crusher designs will operate slightly differently, but how they work is comparable across the board. All jaw crushers reduce large sized rocks ore, or different materials by means of a compression action. A fixed jaw, mounted in a V-shaped alignment, is the stationary breaking surface, while a movable, “swing” jaw exerts force on the feed material by pushing it against the stationary plate.
The area at the bottom of the V-aligned jaw plates is the output gap that dictates the size of the crushed product from the jaw crusher. The rock stays in the jaws until it is small enough to pass through the gap.
Which are Better: Jaw or Cone Crushers?
While jaw crushers may continually be a smart primary crusher stage preference for many operations, it’s true that more recent cone crushers are increasingly taking their place due to versatility. Cone crushers and jaw crushers both work by way of compression, reducing materials by squeezing them until they smash apart.
The benefit that cone crushers provide over jaw crushers is their ability to produce a more cubical product comparable to impact crushers. Cone crushers have traditionally been used as secondary and from time to time tertiary crushing stations.
As far as answering whether or not one type of crusher is better than another, context is key. Everything comes down to what your production needs and goals are.
How Do I Pick the Best Crushers for my Business?
It’s true that crushers are customizable to assist you extract material, break it down into usable product, and get it to market most economically and efficiently. The best way to find the best crushers for your unique operation is to work with a knowledgeable material handling solutions partner like Tricon Mining Equipment.
The right partner can assist you in designing a custom crushing circuit to improve your productivity and upgrade your operations across the board.