When To Rotate Jaw Plates?

Removal of Jaw Plate.

The jaw crusher mainly relies on the interaction between the toothed lining plates of the moving and stationary jaw plates to split materials. Therefore, the toothed lining plates are most susceptible to wear or impact cracking. 

According to the material flow path, it can be seen that the lining plates of the dynamic and static jaw plates wear the most, mainly in the middle and lower parts. Generally, when 3/5 of the tooth height is worn away, the lining plate can no longer be used. In order to save the operating cost of the equipment, the toothed lining plate can be turned around, that is, the relatively intact teeth on the upper part are installed in the middle and lower parts of the moving and static jaw plates and continue to be used. When the wear of the entire toothed liner reaches the replacement requirement, the liner can be replaced as a whole.

When replacing a new toothed liner, the back of the liner must fit closely with the moving and static jaw plates, and no lifting is allowed. Under normal circumstances, the back of the liner will be rough machined to ensure flatness.

Repair of Jaw Plate.

The main faults of the dynamic and static jaw plates of the jaw crusher include cracks, breakage, bearing hole grinding, wear or deflection, and connecting screw tripping. Cracks are a common failure of crushers. 

The general sequence of crack repair: determine the existence of cracks, clean the cracks, and treat the cracks. If cracks are suspected to be invisible to the naked eye, white powder or magnetic particle inspection can be used to determine whether cracks exist. After the cracks are identified, they need to be cleaned before proceeding to the next processing stage. Crack treatment is usually done by repair welding. 

First, drill round holes with a diameter of about 5mm at both ends of the crack, and the depth is about 1.1 to 1.3 times greater than the depth of the crack. Then use gas cutting to cut the crack into a V-shaped or X-shaped groove. 

Finally, select the correct welding rod according to the jaw plate material, and pre-weld. Repair welding is performed after heating, and internal stress is dealt with after welding. Breakage is also a common failure of the jaw plate, which usually occurs suddenly. 

After verification in actual production, appropriate welding technology can be used for the broken movable jaw plate, and the jaw plate can be completely repaired. Before welding, it is necessary to complete the groove forming, preheating and other technical treatments before welding. The bearing hole grinding deviation is mainly due to improper installation or machining that does not meet the requirements. 

After the crusher has been running for a period of time, the bearing hole grinding deviation problem occurs. The treatment method is generally to use repair welding and reprocessing. After repair welding, the bearing hole is bored to restore the assembly size of the bearing hole. 

When welding, pay attention to the fact that the current does not need to be too high to prevent the repair welding part from being difficult to process during subsequent machining.