What is a Jaw Crusher?
A Jaw Crusher is a piece of machinery that is typically used as the primary crushing phase of an application to break larger sized feed material into smaller pieces so they can be passed along the chain. The Jaw Crusher is a very versatile machine with the ability to adapt to a range of different applications no matter the hardness or abrasiveness of the material. The material processed within a Jaw Crusher can be used as a product or it can be passed along the chain to be reduced further by a secondary crusher such as an impact or cone crusher. The reason that a Jaw Crusher is suited to primary crushing is due to the process a jaw uses to break material. Material becomes trapped between two jaw faces and the mechanical pressure that moves the faces back and forward leads to the bulky material breaking into pieces.
How does a Jaw Crusher work?
The Jaw Crusher consists of a fixed jaw plate which remains static, this is often mounted within the crusher mainframe and a movable jaw plate which acts as the pushing force when the material enters the chamber. The two jaw plates are positioned in a ‘V’ shape, so the material falls into the top where the gap is larger and as you travel down the jaw plates the space between the jaw plates decreases. The angle at which the jaw plates are positioned is known as the nip angle which is completely adjustable with the Anaconda J12 Jaw Crusher. To facilitate the movement, there is an eccentric shaft passing through the top of the moveable jaw plate, furthermore this shaft is attached to a toggle plate which pivots. This allows the jaw face to move in a backward and forward motion. The backward and forward motion leads to a crushing action being created on the material fed into the chamber. The material overcomes compression between the two jaw plates, this pressure reduces the size of the material as it travels lower down the jaw plates until it reaches the point where the material can exit from the chamber. The CSS (Closed Side Setting) is the gap between the fixed jaw plate and the moveable Jaw plate, with the Anaconda J12 Jaw Crusher the CSS can be fully adjusted to meet the necessary specification of material a customer requires.
What materials can Jaw Crushers process?
The Jaw Crusher can adjust to multiple different applications with the capability of processing almost all types of rock regardless of how tough the material is; From the harder stone such as basalt right through to the softer stone such as limestone. Dependant on the feed material and the required size of the product this will have a direct correlation on the throughput as each application is different. The jaw crusher can also be easily suited to recycling applications where the feed material may be contaminated with steel rebar. The Anaconda J12 Jaw Crusher is accustomed to accommodating all types of applications with specific features to eliminate obstacles for the end user, example : overband magnet across the tail conveyor in order to retrieve metal contaminates from the crushed product.
What applications suit Jaw Crusher best?
Jaw Crushers are used predominately for primary crushing in quarries and mining applications for hard/medium types of aggregate and ore. The Jaw Crusher facilitates larger pieces of material being fed directly into the system without having to be processed at all beforehand. Using a Jaw Crusher can be a huge cost saving solution as there is less drilling and blasting costs incurred when getting the material prepared for crushing. The beauty of the J12 Jaw Crusher is that it can be set-up and ran alongside multiple crushing stages or work directly with a screen.
There are certain applications where rough and relatively large material can be advantageous and in these circumstances a Jaw crusher is the ideal machine to place into application.
Positives of using a Jaw Crusher…
When it comes to Jaw Crushers there are many different advantages. This includes elements such as versatility, straightforward operation and how easy it is to maintain. Also, unlike secondary and tertiary crushers the wear on the Jaw is minimal.
When a Jaw Crusher has been set-up and commissioned correctly it is able to achieve a high output whilst also minimising costs with a low cost per tonne. Additionally, a jaw can adapt to several different scenarios and can crush both soft and hard abrasive rock. Within any Jaw Crusher the main wear parts include both the static/moving jaw plates and the cheek plates. With the Anaconda J12 Jaw Crusher accessibility is in abundance and changing these parts is quick and easy.
Implementing a Jaw Crusher into your crushing application…
Jaw Crushers are predominately used in the first stage of any crushing application as they can deal with larger sizes of feed material which reduces the costs for the user. Some applications will require a finer product and to process fine sizes additional crushers such as secondary and tertiary (impactors and cones) will be required. When a number of crushers and screens come together, and the material is fed directly from one to another this term is often referred to as a ‘Crushing Train’ which can be configurated in a number of different ways in an effort to generate the required specifications.
It is very important to first assess the feed material itself to make sure you assemble the train correctly and after this look at the fractions you want to achieve throughout the train as a final product. For example, if a feed material is bulky but also quite high in fines rather than beginning with a Jaw it may be beneficial to implement an Anaconda Scalping screen beforehand. The scalping screen will cut out the fines from entering the jaw and help with the efficiency of the operation by preventing a build up in the chamber. This will reduce blockages and eliminate unnecessary wear increasing the life expectancy of your consumables.
What kind of quality do Jaw Crushers achieve?
Jaw Crushers are not renowned for the quality of the final product as the breaking of the rock is predetermined by weaknesses in the stone. Therefore, it is hard to guarantee the shape and size of the aggregate passing through the universal chamber. Majority of applications that involve crushing will lead to a fine final product being created and therefore a Jaw Crusher would not be the most feasible option as secondary/tertiary crushing will be required to process the material to the required size.
Jaw Crushers focus specifically on breaking down larger material to a large sized processed product and therefore they are not built to produce a high volume of small quality product. The Jaw crusher can produce a product that can be fed directly into a secondary crusher in the most cost-effective way possible. If the end material required by the user is larger material to be used as rough fill, then the Jaw Crusher will be capable of processing a quality product in this circumstance.
How to maintain your Jaw Crusher to increase lifespan and performance…
Like all machines it is important to maintain and service regularly to keep the machine working at optimum productivity. With all Anaconda products coming with a service schedule and recommended spare parts list we take the hassle out of keeping your machine maintained, with unchallenged support from our aftersales and technical support team we are by your side every step of the way. It is Anaconda’s philosophy that the process only begins after the sale, it doesn’t end. Important tips to look out for include:
- Regular Checks and Reviews
- Assess the machine manual and make sure all checks noted are conducted regularly
- Consistently check the wearable parts (Jaw plates and cheek pieces) to ensure they are fit for purpose
- Check the bolts on the jaw plates and cheek pieces regularly to ensure they are secure
- Always check the material size being produced to ensure CSS is set to the correct setting
- Do not use jaw plates until they become much too thin as this will not allow for ultimate utilisation of the jaw plates. If they are caught in good time then it allows for the plates to be changed over giving you more life in your wear parts and saving you money
- General Operation
- To maximise the production of the unit continuously feed the chamber, this will help with reduction by putting strain on the equipment at the top of the chamber to push it down
- Avoid the system being fed gradually it must be consistent or it will wear the lower part of the jaw plate
- Ensure that the feed material has a varied gradation when possible as this will allow more material to enter the jaw at once and limit the wear on specific areas of the jaw plates
- When feed material is rich in fine material allow the grizzly section within the feeder to eliminate the fines before heaping the material into the hopper
- Cleanliness
- Ensure the environment around the area is clear and when machine is off remove any dirt deposits that may be on the surface of the crusher and tracks
- Clean out breather filters and install new oil filters as per the service schedule
- Assess all seals to check for any damage and if identified change seal
- It is very important to keep the oil systems free of any contaminates, when changing oil at the regular servicing intervals be sure to remove dirt deposits from the oil tanks as this will contaminate the new oil