What are the common crushing methods of crushers, and what should be done if the crusher is clogged?

Blockage is one of the problems that many crushers encounter. Recently, it was learned that a certain cement plant's cone crusher also faced this issue. How did it solve it? Let's take a look!

After investigation, it was found that the main reason for the blockage and shutdown was that too much material accumulated in the lower chamber of the crusher, blocking the moving cone and causing the motor to overload and shut down. There are usually two situations that cause the shutdown:

(1) The crusher has a high output, and the plate conveyor cannot remove the material in time;

(2) Downstream equipment shuts down while the crusher continues to crush. Once this situation occurs, all materials in the crushing chamber must be cleared before the machine can be restarted, which is time-consuming and labor-intensive, generally taking at least 3 to 4 hours to complete.

To prevent blockage, various solutions have been implemented, and ultimately, a sound and light (alarm bell and light) indicator was used to directly guide the unloading, which was very effective.

Specific implementation steps

Since the operating current of the heavy plate conveyor under the crusher has a good correlation with the amount of material in the lower chamber, and every time the material in the lower chamber causes the crusher to shut down, the current of the plate conveyor exceeds a fixed peak value (38A), while the no-load current is also a fixed value (18A). Therefore, a solution was formulated based on the current characteristics of the plate conveyor.

That is, install an electric bell and alarm flashing light at the unloading port of the crusher, directly connected to the relay in the electrical cabinet. When the plate conveyor reaches a set current value (such as 33A), the relay pulls in, the alarm light starts flashing, and the bell rings. If the downstream equipment shuts down and the current of the plate conveyor is zero, the sound and light alarm will also provide a prompt. After receiving the alarm prompt, the dumper driver will stop unloading, thus preventing blockage.

The set alarm current value for the plate conveyor should be appropriate, not too low or too high. If it is too low, the crushing chamber will often run out of material, and stones may hit the plate conveyor; if set too high, the lower chamber will have too much material, and the buffer space will be insufficient, which can easily lead to blockage if the downstream equipment fails. Practice has proven that the set value of 33A ensures continuous and stable discharge from the crusher while leaving enough buffer space in the lower chamber to effectively prevent blockage.

What are the common crushing methods for crushers?

Jaw Crusherhttps://www.hxjq.cn/1.html Crushing method: Swing compression type

The motor drives the belt and pulley, causing the moving jaw to move up and down through the eccentric shaft. When the moving jaw rises, the angle between the elbow plate and the moving jaw increases, pushing the moving jaw plate closer to the fixed jaw plate, crushing or splitting the material to achieve the crushing purpose;

When the moving jaw descends, the angle between the elbow plate and the moving jaw decreases, and the moving jaw plate, under the action of the pull rod and spring, moves away from the fixed jaw plate, allowing the crushed material to be discharged from the lower opening of the crushing chamber.

Cone Crusherhttps://www.hxjq.cn/6.html Crushing method: Layered crushing type

The rotation of the motor drives the belt pulley or coupling, and the cone crusher's drive shaft and cone part perform a swinging motion around a fixed point under the action of the eccentric sleeve;

This causes the cone crushing wall to alternately approach and leave the surface of the fixedly mounted adjusting sleeve, allowing the ore to be continuously impacted, compressed, and bent in the crushing chamber, thus achieving the crushing of the ore.

Impact Crusher Crushing method: Impact + Strike crushing type

Driven by the motor, the rotor rotates at high speed. When the material enters the area of the plate hammer, it is crushed by the impact of the plate hammer on the rotor, then thrown towards the impact device for further crushing, and then bounced back from the impact liner to the plate hammer area for re-crushing;

This process is repeated, and the material is crushed from large to small in the first, second, and third impact chambers until it is crushed to the required particle size and discharged from the outlet.

Hammer Crusherhttps://www.hxjq.cn/13.html Crushing method: Impact + Strike crushing type

The material enters the crusher and is crushed by the impact of the high-speed rotating hammer. The crushed material gains kinetic energy from the hammer and rushes towards the baffle and screen bars inside the frame. Meanwhile, the materials collide with each other and undergo multiple crushings;

Materials smaller than the gap between the screen bars are discharged through the gap, while larger materials are crushed again by the hammer's impact, grinding, and pressing on the screen bars, allowing the material to be squeezed out through the gap to obtain the desired particle size product.

What are the advantages and disadvantages of commonly used crushers?

Advantages and disadvantages of Jaw Crusher

Advantages: The "V" shaped crushing chamber and the principle of compression operation give it high crushing force and large crushing ratio, with a simple and compact structure that is easy to install and maintain. The optimized jaw plates, lining plates, and other wear parts are more wear-resistant and durable.

Disadvantages: Not suitable for crushing materials with varying hardness, and the moisture content of the material should not exceed 10%. If the moisture content is too high, it is easy to cause blockage on the jaw plate, affecting the crushing efficiency.

Advantages and disadvantages of Cone Crusher

Advantages: High manganese steel wear parts and hydraulic devices give it strong compressive strength, large crushing force, and ease of maintenance. Additionally, the cone crusher has undergone certain improvements, reducing the content of needle-like materials in the finished product.

Disadvantages: Not suitable for crushing wet and sticky ores, the machine is relatively heavy, and the equipment investment cost is high. When processing soft materials, there may be excessive stone powder.

Advantages and disadvantages of Impact Crusher

Advantages: The discharge particle shape is complete, multi-angular, and of very good quality. Users can adjust and control the finished particle size themselves, and the equipment has good sealing properties. Additionally, due to the impact crushing principle, it produces less stone powder during operation, making it environmentally friendly.

Disadvantages: The wear of the hammer and impact plate is relatively fast, requiring more frequent replacement, especially when crushing hard materials, where wear occurs more quickly; poor adaptability to materials containing water and mud, and it is extremely difficult to clear blockages once they occur.