Jaw crusher is a widely used crushing machine at present. It has a simple structure, convenient operation, large processing capacity, and is strong and durable. It is favored by all walks of life. However, because jaw crusher handles hard materials for a long time, its parts are replaced more frequently than other mining machinery. Below we will introduce in detail the precautions for disassembly and replacement of jaw crusher.
1. Replacement method of jaw crusher
The most frequent repair project of jaw crusher is to replace the thrust plate. For crushers with integral connecting rods, to remove the thrust plate, you must first unscrew the baffle screw, cut off the dry oil lubricating oil pipe, and hang the thrust plate on the crane hook or other lifting equipment, and then loosen the spring at one end of the horizontal pull rod, push the movable jaw to the fixed jaw, and remove the thrust plate. If you want to remove the rear thrust plate, then you should pull the connecting rod together with the front thrust plate and the movable jaw to remove the rear thrust plate.
After the thrust plate is removed, cut off the thin oil lubrication pipe and cooling water pipe, support the bottom of the connecting rod with a bracket, and then remove the connecting rod cover before lifting the connecting rod.
The main shaft of the jaw crusher should be removed together with the pulley and flywheel during disassembly. During the disassembly process, move the motor (with the belt) as close to the crusher as possible along the slide rail, remove the V-belt, and then lift the shaft with a crane.
For the disassembly of the movable jaw, the dry oil lubrication oil pipe must be cut off first, the pull rod must be disassembled, the bearing cover must be removed, and then the movable jaw must be pulled out with a crane or other lifting equipment.
2. Replacement conditions for jaw crusher parts
1. Liner replacement conditions
The fixed jaw liner (tooth plate), movable jaw liner (tooth plate), and side liner (guard plate) of the jaw crusher are easy to wear. Severe wear will increase the product particle size. In the initial wear, the tooth plate can be turned around for use, or the upper and lower pieces can be turned around for use. The wear of the jaw plate is mostly in the middle and lower part. When the tooth height is worn off by 3/5, a new liner needs to be replaced. When the liner plates on both sides are worn off by 2/5, they also need to be replaced with new ones.
2. Conditions for replacing the mandrel, eccentric shaft and bearing of the jaw crusher
If the wear of the shaft is very small, it can be turned on a lathe just to repair its geometry, so that the journal reaches the correct geometry, and then the inner diameter of the bearing is reduced accordingly. However, after several such treatments, if the journal size is reduced by 5% compared with the original, turning is not allowed, and a new shaft should be replaced.
The jaw crusher works under impact load. The babbitt lining on the bearing has a working period of about two years. If it exceeds the period, it needs to be recast.
If the eccentric shaft and the bearing, the mandrel and the bearing are worn, and the top clearance is greater than 1.5 times the original assembly clearance, it is necessary to add pads for adjustment or replacement; if the oil groove is worn by 1.5 mm, the oil groove should be reopened and adjusted. When the gap between the connecting rod head cover and the eccentric shaft is worn to more than 1.5 times the assembly gap, it is also necessary to add pads for adjustment or replace with new ones.
When the babbitt alloy on the bearing shell has deep peeling or large scratches, it should be recast. The following requirements are imposed on the quality of the processed bearing shell: the color of the babbitt alloy surface should be uniform, matte, and silvery white; the surface layer of the babbitt alloy should not have ash, cracks, sand holes, shrinkage holes, etc. and peeling.
The above are some precautions for the replacement of jaw crusher parts. Let everyone know this knowledge because from the annual sales of Xingaonai Mining, a leading enterprise in my country's mining machinery, the annual sales of jaw crushers alone are very good, which objectively reflects the huge market demand for jaw crushers. Through this article, readers can have some understanding of the replacement conditions of jaw crusher parts, which can save certain costs for enterprises using jaw crushers and improve corporate benefits.