The Common Q&A about Spare Parts for Jaw Crusher (II)

In this text, let s talk about the common Q & A about the jaw crusher

Spare parts of Jaw Crusher – the main reason of why tooth plate wears out? 


Through Analysis, the main reason of tooth plate wearing is due to the comparatively sliding compared with tooth plate, which leads to the distortion caused by frequent squeezing between metal scrap and surface material of tooth plate. The aging of the metal material will fall off finally. The wearing procedure is: 

① The material frequently crushes the chopping teeth plate. On the surface area of the tooth plate, or the metal truck part caused by squeezing, generates flaws that leads to the metal fall off directly, hence, forms the abrasive dust. 

② The material frequently crushes the chopping teeth plate that cause the metal partially curled up and overturned or cracks. The cracked and curled up parts will fall out due to squeezing and impact force. Then the metal fall out together with the crushing material as the abrasive dust. 

③ The material have a slightly short stroke compared with tooth plate

Due to the size difference of jaw crushers, the feeding material granularities and sharpness will have a different squeezing and impact force towards the tooth plate. The larger the machine is, the more impact force it will withstand. Despite the consideration of material squeezing force and chopping force, the impact force and bending force should also be taken into consideration. Hence large type tooth plate should use. 

Through above wearing analysis we can know that, for the tooth plate material, we should employ materials with high strength, high tenacity quality. At the mean time, the structure of the tooth plate should be improved to reduce the comparative movement between the material and the tooth plate, which is not only good to improve efficiency, but also improve the material service life. 


 

Spare parts of jaw crusher – anchor bolt fracture reason and the solution 


(1) Reason analysis 

The causes of anchor bolt fracture mainly include:

① There are plenty of stones inside the crusher, when the machine works in overload, the anchor bolts bears high shear stress that lead to be broken.

② The machine load vibration or the damping board rot that lead to nut loose. The whole frame does back and forth movement, wearing the bolts, the machine works with “fault”, and eventually leads to bolt fracture if not found in time.

③ Crusher bearing damage, the eccentric load increase during operation, which leads to the bolt fracture.

(2) The solution

① Demolition of the original concrete foundation, replacement of anchor bolt, pouring again.

② Translation of the crusher, drill the new holes based on the original concrete, anchoring the anchor bolt with resin mortar.

③ Pour concrete respectively in the front and back of the crusher frame, embedded a U-steel close to the frame side, and left 5-10mm gap between them, then fix the broken bolt, fasten the bolt, and add the oblique iron between frame and U-steel.
 

Spare parts of jaw crusher – the function of thrust plate


Thrust plate is called toggle plate, which functions are as follows:

① Support swing jaw plate and pass the crushing force to frame back wall.

② Replacement of different thrust plate can adjust the size of discharge opening.

③ It is functioned as the safety device. When the over hardness materials or foreign matter as metal block enter into the crushing cavity, the thrust plate will be broken to protect other parts free from damage. 

Thrust plat is the part that has simple structure, lowest cost, easy made and replaced. It is made from grey cast iron with low strength. Its section size should pass the normal stress rather than the abnormal stress that generates from the machine overload.