Jaw Crusher

Jaw crusher is an early crushing equipment. It is still widely used in metallurgy, chemical industry, building materials, electric power, transportation and other industrial sectors for coarse, medium and fine crushing of various ores and rocks with compressive strength of 147-245MPa due to its simple structure, strong, reliable operation, easy maintenance and overhaul, and relatively low production and construction costs. In recent years, our factory has specially developed a powerful jaw crusher to meet the needs of metallurgy, mining, construction and other industrial sectors for crushing high-strength and high-hardness micro-carbon ferrochrome.

Working Principle

This series of crushers work in a kinetic extrusion type. Its working principle is: the motor drives the belt and pulley, and the movable jaw moves up and down through the eccentric shaft. When the movable jaw rises, the angle between the toggle plate and the movable jaw increases, thereby pushing the movable jaw plate closer to the fixed jaw plate, and at the same time, the material is crushed or split to achieve the purpose of crushing; when the movable jaw descends, the angle between the toggle plate and the movable jaw decreases, and the movable jaw plate leaves the fixed jaw plate under the action of the pull rod and spring. At this time, the crushed material is discharged from the lower opening of the crushing chamber. As the motor rotates continuously, the movable jaw of the crusher performs periodic movement to crush and discharge materials, realizing mass production.

Other instructions

1. Precautions for installing a jaw crusher?

(1) Since the jaw crusher vibrates greatly during operation, the machine should be installed on a concrete foundation. In order to reduce vibration, noise and the impact on the foundation of nearby buildings and structures, a hardwood pad, rubber belt or other shock-absorbing material should be placed between the crusher and the concrete foundation.

(2) The foundation discharge chute should be paved with a layer of metal plate and have a sufficient inclination angle (determined by the fluidity of the material and not less than 50°) to avoid hindering the smooth discharge of the crushed product.

(3) The size of the discharge port should be adjusted according to the required product size. When adjusting, the T-bolt and the tension spring should be loosened. Use the lifting bolt to push open the adjustment seat, insert or remove the gasket of the corresponding thickness, and then retract the lifting bolt. Under the action of the deadweight of the movable jaw, the adjustment seat is tightly attached to the frame ear seat, and the gasket group is pressed together. After that, adjust the spring preload to ensure that the thrust plate and the thrust plate pad are tightly attached when the machine is working. However, the preload should not be too large. As long as there is no knocking sound, finally lock the adjustment seat.

2. What are the precautions for no-load test run?

(1) When the jaw crusher runs continuously for 2 hours, the bearing temperature rise shall not exceed 30℃.

(2) All fasteners of the jaw crusher should be firm and not loose.

(3) The flywheel and the groove wheel run smoothly.

(4) All friction parts of the jaw crusher are free of scratches, chips and grinding, and there is no abnormal noise.

(5) The adjustment device of the discharge port of the jaw crusher should be able to ensure the adjustment range of the discharge port.

3. What are the common causes of jaw plate fracture in jaw crushers?

The jaw crusher mainly uses the striking energy of the movable jaw and the counterattack energy of the jaw plate to achieve the purpose of crushing materials. The jaw plate of the jaw crusher plays an important role in the crushing process. The common fault of the jaw plate is fracture. After excluding the unqualified manufacturing process of the jaw plate produced by the jaw crusher manufacturer, the fault of the equipment itself can be divided into: the size of the discharge port of the jaw crusher does not meet the specifications. When a large material enters the crushing chamber, the load increases and the load of the jaw plate increases accordingly; it is also related to the toggle plate and toggle plate pad. If the quality of the toggle plate and toggle plate pad is unqualified, when there is a strong impact force and a self-breaking protection operation is required, the toggle plate cannot play the self-breaking protection function of the application.

Human factors: the tension of the pull rod spring inside the equipment fails after a period of use and the new spring device is not replaced in time; the eccentric shaft, bearing, fixing bushing and movable jaw are not assembled properly, the movable jaw is displaced during operation, and collides and breaks with the inner wall guard plate of the machine body; the feeding is uneven, such as the material is biased in the crushing chamber or the lower hopper is tilted too much, the movable jaw directly contacts and collides with the material, increasing the wear and impact intensity.

Analyze the reasons for the jaw plate breakage. In production, we should try our best to avoid the unfavorable factors that damage the jaw plate and shorten its life. Only by ensuring the normal operation of the jaw crusher can we greatly improve the production efficiency.

4. What are the characteristics of the movable jaw movement of the jaw crusher?

(1) When the jaw plate presses the material, the movable jaw plate will partially move downward with the material, which will generate a force that prompts the material to move downward, thereby accelerating the discharge speed and increasing the output. Practice has proved that the output of the complex swing jaw crusher is about 20%-30% higher than that of the simple swing jaw crusher of the same specification.

(2) The horizontal swing of the upper part of the movable jaw is greater than that of the lower part, so that large pieces of material can be easily crushed in the upper part. The working area of ​​the entire jaw plate is relatively uniform, which conforms to the crushing principle and is conducive to the uniformity of the jaw plate's working load.

(3) Since the lower part of the movable jaw has a large downward vertical moving force during unloading, it can not only promote unloading, but also repeatedly flip the crushed products, reducing long flake products and unloading them in the form of cubic blocks. In a complex swing jaw crusher, in addition to being crushed, split and broken, the material is also subjected to grinding, which increases the crushing force of the material and is also conducive to improving production capacity.

(4) Due to the large vertical displacement of the movable jaw, the friction between the material and the jaw plate is aggravated, causing the jaw plate to wear faster. At the same time, it aggravates the over-crushing phenomenon, so the dust generated is larger.

(5) When crushing materials, the movable jaw bears a huge crushing force, part of which acts on the eccentric shaft and bearings. Especially for large complex swing jaws, the force is very large. Therefore, complex swing jaw crushers are usually made into medium and small sizes.